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Nathan Goodyear

Cancer cells metabolically "fertilize" the tumor microenvironment with hydrogen peroxid... - 0 views

www.ncbi.nlm.nih.gov/...PMC3180189

cancer reverse warburg effect warburg effect NF-kapppB HIF-1alpha Cav-1 H2O2

shared by Nathan Goodyear on 12 Nov 14 - No Cached
  • reducing oxidative stress with powerful antioxidants, is an important strategy for cancer prevention, as it would suppress one of the key early initiating steps where DNA damage and tumor-stroma metabolic-coupling begins. This would prevent cancer cells from acting as metabolic “parasites
  • Oxidative stress in cancer-associated fibroblasts triggers autophagy and mitophagy, resulting in compartmentalized cellular catabolism, loss of mitochondrial function, and the onset of aerobic glycolysis, in the tumor stroma. As such, cancer-associated fibroblasts produce high-energy nutrients (such as lactate and ketones) that fuel mitochondrial biogenesis and oxidative metabolism in cancer cells. We have termed this new energy-transfer mechanism the “reverse Warburg effect.
  • Then, oxidative stress, in cancer-associated fibroblasts, triggers the activation of two main transcription factors, NFκB and HIF-1α, leading to the onset of inflammation, autophagy, mitophagy and aerobic glycolysis in the tumor microenvironment
  • ...38 more annotations...
  • oxidative stress and ROS, produced in cancer-associated fibroblasts, has a “bystander effect” on adjacent cancer cells, leading to DNA damage, genomic instability and aneuploidy, which appears to be driving tumor-stroma co-evolution
  • tumor cells produce and secrete hydrogen peroxide, thereby “fertilizing” the tumor microenvironment and driving the “reverse Warburg effect.”
  • This type of stromal metabolism then produces high-energy nutrients (lactate, ketones and glutamine), as well as recycled chemical building blocks (nucleotides, amino acids, fatty acids), to literally “feed” cancer cells
  • loss of stromal caveolin (Cav-1) is sufficient to drive mitochondrial dysfunction with increased glucose uptake in fibroblasts, mimicking the glycolytic phenotype of cancer-associated fibroblasts.
  • oxidative stress initiated in tumor cells is transferred to cancer-associated fibroblasts.
  • Then, cancer-associated fibroblasts show quantitative reductions in mitochondrial activity and compensatory increases in glucose uptake, as well as high ROS production
  • These findings may explain the prognostic value of a loss of stromal Cav-1 as a marker of a “lethal” tumor microenvironment
  • aerobic glycolysis takes place in cancer-associated fibroblasts, rather than in tumor cells, as previously suspected.
  • our results may also explain the “field effect” in cancer biology,5 as hydrogen peroxide secreted by cancer cells, and the propagation of ROS production, from cancer cells to fibroblasts, would create an increasing “mutagenic field” of ROS production, due to the resulting DNA damage
  • Interruption of this process, by addition of catalase (an enzyme that detoxifies hydrogen peroxide) to the tissue culture media, blocks ROS activity in cancer cells and leads to apoptotic cell death in cancer cells
  • In this new paradigm, cancer cells induce oxidative stress in neighboring cancer-associated fibroblasts
  • cancer-associated fibroblasts have the largest increases in glucose uptake
  • cancer cells secrete hydrogen peroxide, which induces ROS production in cancer-associated fibroblasts
  • Then, oxidative stress in cancer-associated fibroblast leads to decreases in functional mitochondrial activity, and a corresponding increase in glucose uptake, to fuel aerobic glycolysis
  • cancer cells show significant increases in mitochondrial activity, and decreases in glucose uptake
  • fibroblasts and cancer cells in co-culture become metabolically coupled, resulting in the development of a “symbiotic” or “parasitic” relationship.
  • cancer-associated fibroblasts undergo aerobic glycolysis (producing lactate), while cancer cells use oxidative mitochondrial metabolism.
  • We have previously shown that oxidative stress in cancer-associated fibroblasts drives a loss of stromal Cav-1, due to its destruction via autophagy/lysosomal degradation
  • a loss of stromal Cav-1 is sufficient to induce further oxidative stress, DNA damage and autophagy, essentially mimicking pseudo-hypoxia and driving mitochondrial dysfunction
  • loss of stromal Cav-1 is a powerful biomarker for identifying breast cancer patients with early tumor recurrence, lymph-node metastasis, drug-resistance and poor clinical outcome
  • this type of metabolism (aerobic glycolysis and autophagy in the tumor stroma) is characteristic of a lethal tumor micro-environment, as it fuels anabolic growth in cancer cells, via the production of high-energy nutrients (such as lactate, ketones and glutamine) and other chemical building blocks
  • the upstream tumor-initiating event appears to be the secretion of hydrogen peroxide
  • one such enzymatically-active protein anti-oxidant that may be of therapeutic use is catalase, as it detoxifies hydrogen peroxide to water
  • numerous studies show that “catalase therapy” in pre-clinical animal models is indeed sufficient to almost completely block tumor recurrence and metastasis
  • by eliminating oxidative stress in cancer cells and the tumor microenvironment,55 we may be able to effectively cut off the tumor's fuel supply, by blocking stromal autophagy and aerobic glycolysis
  • breast cancer patients show systemic evidence of increased oxidative stress and a decreased anti-oxidant defense, which increases with aging and tumor progression.68–70 Chemotherapy and radiation therapy then promote further oxidative stress.69 Unfortunately, “sub-lethal” doses of oxidative stress during cancer therapy may contribute to tumor recurrence and metastasis, via the activation of myofibroblasts.
  • a loss of stromal Cav-1 is associated with the increased expression of gene profiles associated with normal aging, oxidative stress, DNA damage, HIF1/hypoxia, NFκB/inflammation, glycolysis and mitochondrial dysfunction
  • cancer-associated fibroblasts show the largest increases in glucose uptake, while cancer cells show corresponding decreases in glucose uptake, under identical co-culture conditions
  • Thus, increased PET glucose avidity may actually be a surrogate marker for a loss of stromal Cav-1 in human tumors, allowing the rapid detection of a lethal tumor microenvironment.
  • it appears that astrocytes are actually the cell type responsible for the glucose avidity.
  • In the brain, astrocytes are glycolytic and undergo aerobic glycolysis. Thus, astrocytes take up and metabolically process glucose to lactate.7
  • Then, lactate is secreted via a mono-carboxylate transporter, namely MCT4. As a consequence, neurons use lactate as their preferred energy substrate
  • both astrocytes and cancer-associated fibroblasts express MCT4 (which extrudes lactate) and MCT4 is upregulated by oxidative stress in stromal fibroblasts.34
  • In accordance with the idea that cancer-associated fibroblasts take up the bulk of glucose, PET glucose avidity is also now routinely used to measure the extent of fibrosis in a number of human diseases, including interstitial pulmonary fibrosis, postsurgical scars, keloids, arthritis and a variety of collagen-vascular diseases.
  • PET glucose avidity and elevated serum inflammatory markers both correlate with poor prognosis in breast cancers.
  • PET signal over-estimates the actual anatomical size of the tumor, consistent with the idea that PET glucose avidity is really measuring fibrosis and inflammation in the tumor microenvironment.
  • human breast and lung cancer patients can be positively identified by examining their exhaled breath for the presence of hydrogen peroxide.
  • tumor cell production of hydrogen peroxide drives NFκB-activation in adjacent normal cells in culture6 and during metastasis,103 directly implicating the use of antioxidants, NFκB-inhibitors and anti-inflammatory agents, in the treatment of aggressive human cancers.
  • Nathan Goodyear on 12 Nov 14
     
    Good description of the communication between cancer cells and fibroblasts.  This theory is termed the "reverse Warburg effect".
Nathan Goodyear

Inflammatory cause of metabolic syndrome via brain stress and NF-κB - 0 views

www.ncbi.nlm.nih.gov/...PMC3314172

metabolic syndrome TLR cytokines hypothalamus brain neurology metabolic syndrome NF-kappaB DIO diet induced obesity over nutrition nutrition inflammation

shared by Nathan Goodyear on 09 Jul 13 - No Cached
  • Mechanistic studies further showed that such metabolic inflammation is related to the induction of various intracellular stresses such as mitochondrial oxidative stress, endoplasmic reticulum (ER) stress, and autophagy defect under prolonged nutritional excess
  • intracellular stress-inflammation process for metabolic syndrome has been established in the central nervous system (CNS) and particularly in the hypothalamus
  • the CNS and the comprised hypothalamus are known to govern various metabolic activities of the body including appetite control, energy expenditure, carbohydrate and lipid metabolism, and blood pressure homeostasis
  • ...56 more annotations...
  • Reactive oxygen species (ROS) refer to a class of radical or non-radical oxygen-containing molecules that have high oxidative reactivity with lipids, proteins, and nucleic acids
  • a large measure of intracellular ROS comes from the leakage of mitochondrial electron transport chain (ETC)
  • Another major source of intracellular ROS is the intentional generation of superoxides by nicotinamide adenine dinucleotide phosphate (NADPH) oxidase
  • there are other ROS-producing enzymes such as cyclooxygenases, lipoxygenases, xanthine oxidase, and cytochrome p450 enzymes, which are involved with specific metabolic processes
  • To counteract the toxic effects of molecular oxidation by ROS, cells are equipped with a battery of antioxidant enzymes such as superoxide dismutases, catalase, peroxiredoxins, sulfiredoxin, and aldehyde dehydrogenases
  • intracellular oxidative stress has been indicated to contribute to metabolic syndrome and related diseases, including T2D [72; 73], CVDs [74-76], neurodegenerative diseases [69; 77-80], and cancers
  • intracellular oxidative stress is highly associated with the development of neurodegenerative diseases [69] and brain aging
  • dietary obesity was found to induce NADPH oxidase-associated oxidative stress in rat brain
  • mitochondrial dysfunction in hypothalamic proopiomelanocortin (POMC) neurons causes central glucose sensing impairment
  • Endoplasmic reticulum (ER) is the cellular organelle responsible for protein synthesis, maturation, and trafficking to secretory pathways
  • unfolded protein response (UPR) machinery
  • ER stress has been associated to obesity, insulin resistance, T2D, CVDs, cancers, and neurodegenerative diseases
  • brain ER stress underlies neurodegenerative diseases
  • under environmental stress such as nutrient deprivation or hypoxia, autophagy is strongly induced to breakdown macromolecules into reusable amino acids and fatty acids for survival
  • intact autophagy function is required for the hypothalamus to properly control metabolic and energy homeostasis, while hypothalamic autophagy defect leads to the development of metabolic syndrome such as obesity and insulin resistance
  • prolonged oxidative stress or ER stress has been shown to impair autophagy function in disease milieu of cancer or aging
  • TLRs are an important class of membrane-bound pattern recognition receptors in classical innate immune defense
  • Most hypothalamic cell types including neurons and glia cells express TLRs
  • overnutrition constitutes an environmental stimulus that can activate TLR pathways to mediate the development of metabolic syndrome related disorders such as obesity, insulin resistance, T2D, and atherosclerotic CVDs
  • Isoforms TLR1, 2, 4, and 6 may be particularly pertinent to pathogenic signaling induced by lipid overnutrition
  • hypothalamic TLR4 and downstream inflammatory signaling are activated in response to central lipid excess via direct intra-brain lipid administration or HFD-feeding
  • overnutrition-induced metabolic derangements such as central leptin resistance, systemic insulin resistance, and weight gain
  • these evidences based on brain TLR signaling further support the notion that CNS is the primary site for overnutrition to cause the development of metabolic syndrome.
  • circulating cytokines can limitedly travel to the hypothalamus through the leaky blood-brain barrier around the mediobasal hypothalamus to activate hypothalamic cytokine receptors
  • significant evidences have been recently documented demonstrating the role of cytokine receptor pathways in the development of metabolic syndrome components
  • entral administration of TNF-α at low doses faithfully replicated the effects of central metabolic inflammation in enhancing eating, decreasing energy expenditure [158;159], and causing obesity-related hypertension
  • Resistin, an adipocyte-derived proinflammatory cytokine, has been found to promote hepatic insulin resistance through its central actions
  • both TLR pathways and cytokine receptor pathways are involved in central inflammatory mechanism of metabolic syndrome and related diseases.
  • In quiescent state, NF-κB resides in the cytoplasm in an inactive form due to inhibitory binding by IκBα protein
  • IKKβ activation via receptor-mediated pathway, leading to IκBα phosphorylation and degradation and subsequent release of NF-κB activity
  • Research in the past decade has found that activation of IKKβ/NF-κB proinflammatory pathway in metabolic tissues is a prominent feature of various metabolic disorders related to overnutrition
  • it happens in metabolic tissues, it is mainly associated with overnutrition-induced metabolic derangements, and most importantly, it is relatively low-grade and chronic
  • this paradigm of IKKβ/NF-κB-mediated metabolic inflammation has been identified in the CNS – particularly the comprised hypothalamus, which primarily accounts for to the development of overnutrition-induced metabolic syndrome and related disorders such as obesity, insulin resistance, T2D, and obesity-related hypertension
  • evidences have pointed to intracellular oxidative stress and mitochondrial dysfunction as upstream events that mediate hypothalamic NF-κB activation in a receptor-independent manner under overnutrition
  • In the context of metabolic syndrome, oxidative stress-related NF-κB activation in metabolic tissues or vascular systems has been implicated in a broad range of metabolic syndrome-related diseases, such as diabetes, atherosclerosis, cardiac infarct, stroke, cancer, and aging
  • intracellular oxidative stress seems to be a likely pathogenic link that bridges overnutrition with NF-κB activation leading to central metabolic dysregulation
  • overnutrition is an environmental inducer for intracellular oxidative stress regardless of tissues involved
  • excessive nutrients, when transported into cells, directly increase mitochondrial oxidative workload, which causes increased production of ROS by mitochondrial ETC
  • oxidative stress has been shown to activate NF-κB pathway in neurons or glial cells in several types of metabolic syndrome-related neural diseases, such as stroke [185], neurodegenerative diseases [186-188], and brain aging
  • central nutrient excess (e.g., glucose or lipids) has been shown to activate NF-κB in the hypothalamus [34-37] to account for overnutrition-induced central metabolic dysregulations
  • overnutrition can present the cell with a metabolic overload that exceeds the physiological adaptive range of UPR, resulting in the development of ER stress and systemic metabolic disorders
  • chronic ER stress in peripheral metabolic tissues such as adipocytes, liver, muscle, and pancreatic cells is a salient feature of overnutrition-related diseases
  • recent literature supports a model that brain ER stress and NF-κB activation reciprocally promote each other in the development of central metabolic dysregulations
  • when intracellular stresses remain unresolved, prolonged autophagy upregulation progresses into autophagy defect
  • autophagy defect can induce NF-κB-mediated inflammation in association with the development of cancer or inflammatory diseases (e.g., Crohn's disease)
  • The connection between autophagy defect and proinflammatory activation of NF-κB pathway can also be inferred in metabolic syndrome, since both autophagy defect [126-133;200] and NF-κB activation [20-33] are implicated in the development of overnutrition-related metabolic diseases
  • Both TLR pathway and cytokine receptor pathways are closely related to IKKβ/NF-κB signaling in the central pathogenesis of metabolic syndrome
  • Overnutrition, especially in the form of HFD feeding, was shown to activate TLR4 signaling and downstream IKKβ/NF-κB pathway
  • TLR4 activation leads to MyD88-dependent NF-κB activation in early phase and MyD88-indepdnent MAPK/JNK pathway in late phase
  • these studies point to NF-κB as an immediate signaling effector for TLR4 activation in central inflammatory response
  • TLR4 activation has been shown to induce intracellular ER stress to indirectly cause metabolic inflammation in the hypothalamus
  • central TLR4-NF-κB pathway may represent one of the early receptor-mediated events in overnutrition-induced central inflammation.
  • cytokines and their receptors are both upstream activating components and downstream transcriptional targets of NF-κB activation
  • central administration of TNF-α at low dose can mimic the effect of obesity-related inflammatory milieu to activate IKKβ/NF-κB proinflammatory pathways, furthering the development of overeating, energy expenditure decrease, and weight gain
  • the physiological effects of IKKβ/NF-κB activation seem to be cell type-dependent, i.e., IKKβ/NF-κB activation in hypothalamic agouti-related protein (AGRP) neurons primarily leads to the development of energy imbalance and obesity [34]; while in hypothalamic POMC neurons, it primarily results in the development of hypertension and glucose intolerance
  • the hypothalamus, is the central regulator of energy and body weight balance [
  • Nathan Goodyear on 09 Jul 13
     
    Great article chronicles the biochemistry of "over nutrition" and inflammation through NF-kappaB activation and its impact on the brain.
Nathan Goodyear

Role of Oxidative Stress and the Microenvironment in Breast Cancer Development and Prog... - 0 views

www.ncbi.nlm.nih.gov/...PMC3950899

cancer oxidative stress warburg effect reverse warburg effect ROS

shared by Nathan Goodyear on 11 Nov 14 - No Cached
  • oxidative stress leads to HIF-1α accumulation
  • Oxidative stress generated by breast cancer cells activates HIF-1α and NFκB in fibroblasts, leading to autophagy and lysosomal degradation of Cav-1
  • increased levels of hydrogen peroxide in exhaled breath condensate from patients with localized breast malignancy, associated with increased clinical severity
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  • Comparing mitochondrial metabolic activity revealed a difference between stroma and epithelial cells
  • Overexpression of NOX4 in normal breast epithelial cells results in cellular senescence, resistance to apoptosis, and tumorigenic transformation, as well as increased aggressiveness of breast cancer cells
  • metalloproteinases (MMP) such as MMP-2, MMP-3, and MMP-9 increase extracellular matrix turnover and are themselves activated by oxidative stress
  • Lowered expression of Cav-1 not only leads to myofibroblast conversion and inflammation but also seems to impact aerobic glycolysis, leading to secretion of high energy metabolites such as pyruvate and lactate that drive mitochondrial oxidative phosphorylation in cancer cells
  • Reverse Warburg Effect
  • secreted transforming growth factor β (TGFβ), insulin-like growth factor (IGF), platelet-derived growth factor (PDGF), fibroblast growth factor 2, and stromal-derived factor 1 (SDF1) are able to activate fibroblasts and increase cancer cell proliferation
  • oxidative stress has an important role in the initiation and preservation of breast cancer progression
  • cancer preventive role of healthy mitochondria
  • the cancer cells produce hydrogen peroxide and by driving the “Reverse Warburg Effect” initiate oxidative stress in fibroblasts. As a result of this process, fibroblasts exhibited reduced mitochondrial activity, increased glucose uptake, ROS, and metabolite production.
  • Oxidative stress results from an imbalance between unstable reactive species lacking one or more unpaired electrons (superoxide anion, hydrogen peroxide, hydroxyl radical, reactive nitrogen species) and antioxidants
  • cancer cells are able to induce drivers of oxidative stress, autophagy and mitophagy: HIF-1α and NFκB in surrounding stroma fibro-blasts
  • Studies show that loss of Cav-1 in adjacent breast cancer stroma fibroblasts can be prevented by treatment with N-acetyl cysteine, quercetin, or metformin
  • However, diets rich in antioxidants have fallen short in sufficiently preventing cancer
  • hydrogen peroxide is one of the main factors that can push fibroblasts and cancer cells into senescence
  • It is widely held that HIF-1α function is dependent upon its location within the tumor microenvironment. It acts as a tumor promoter in CAFs and as a tumor suppressor in cancer cells
  • It was reported that overexpression of recombinant (SOD2) (Trimmer et al., 2011) or injection of SOD, catalase, or their pegylated counterparts can block recurrence and metastasis in mice
  • obstructing oxidative stress in the tumor microenvironment can lead to mitophagy and promote breast cancer shutdown is a promising discovery for the development of future therapeutic interventions.
  • Recent studies show that in the breast cancer microenvironment, oxidative stress causes mitochondrial dysfunction
  • Nathan Goodyear on 11 Nov 14
     
    Really fascinating article on tumor signaling. The article points to a complex signaling between cancer cells and stromal fibroblasts that results in myofibroblast transformation that increases the microenvironment favorability of cancer. This article points to oxidative stress as the primary driving force.  
Nathan Goodyear

Oxidative Stress and Its Relationship With Adenosine Deaminase Activity in Various Stag... - 0 views

www.ncbi.nlm.nih.gov/...PMC3547448

Adenosine Deaminase ADA cancer breast cancer superoxide disumutase glutathione peroxidase oxidative stress inflammation

shared by Nathan Goodyear on 10 Nov 14 - No Cached
  • Reduced SOD activity might be responsible for excessive accumulation of superoxide anions leading to increased free radical mediated injury. Increased free radical production has been shown to be responsible for chromosomal damage leading to mutagenecity, cell proliferation and carcinogenesis. SOD activity showed marked improvement after mastectomy indicating the lowering of oxidative stress.
  • The increased production of reactive oxygen species causes oxidative stress leading to cell proliferation and hence increased inflammatory conditions
  • Superoxide dismutase is an important antioxidant enzyme which decomposes the harmful superoxide anions into hydrogen peroxide thus protects the body from the action of free radicals
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  • Females suffering from breast cancer had significantly decreased Superoxide dismutase (SOD) and reduced glutathione (GSH) levels in comparison to normal females
  • ADA seems to be a promising marker of inflammation in breast cancer thereby suggesting that it can be used as a diagnostic tool to detect the stage of breast cancer along with cytopathological studies
  • In conclusion, our study confirmed the role of oxidative stress in the pathogenesis of breast cancer.
  • Another potent antioxidant molecule is reduced glutathione. It acts as reductant which converts hydrogen peroxide into water and reduces lipid peroxidation products into their corresponding alcohols and thus mediates protective action.
  • In the present study, significantly low SOD activity has been observed in female patients suffering from carcinoma breast both pre as well as post operative in comparison to healthy females.
  • We observed significantly decreased SOD activity and GSH levels in patients belonging to clinical stage 4 as compared to those having stages 1, 2 or 3 of breast cancer.
  • Increased ADA activity in breast cancer patients has also been reported
  • The compromised antioxidant defence system produces the oxidative stress which in turn creates the inflammatory response shown by concomitant increased adenosine deaminase (ADA) activity in female patients.
  • Experimental and epidemiological evidences implicate the involvement of oxygen derived free radical in the pathogenesis of breast cancer.
  • Antioxidant status was highly depressed in advanced stages of breast cancer as compared to initial stage.
  • In the present study, significantly low GSH levels were observed in female patients of carcinoma breast as compared to normal females
  • Walia et al. (1995) reported increased ADA activity in breast cancer patients as compared to age matched normal subjects.
  • These free radicals are able to cause damage to membrane, mitochondria and macromolecules including proteins, lipids and DNA and actively take part in cell proliferation. This cascade in turn generates the inflammatory response and causes the progression of the disease.
  • increased oxidative stress gives rise to inflammation which could further aggravates the disease
  • Breast carcinoma involves a cascade of events that are highly inflammatory.
  • Marked oxidative stress in stage 4 of breast cancer indicated advancement of the disease, hence checking oxidative stress at initial stage could be helpful for controlling the progression of the disease.
  • They concluded that ADA is a better probable parameter for detection of breast cancer
  • Adenosine deaminase enzyme (ADA) catalyzes the conversion of adenosine to inosine which finally gets converted to uric acid
  • serum ADA activity tends to increase with advancing age,
  • Prevalence of oxidative stress gives rise to inflammation.
  • Nathan Goodyear on 10 Nov 14
     
    Study finds a reduction in SuperOxide Dismutase and Glutathione Perioxidase in advancing breast cancer.  Cancer is a high oxidative stress disease that results in inflammation, mitochondrial dysfunction and proliferation.  Adenosine Deaminase (ADA) is proposed to be another biomarker to assess tumor stage.  
Nathan Goodyear

Peripheral oxidative stress in relapsing-remitting multiple sclerosis - 0 views

www.sciencedirect.com/...S0009912012000525

MS multiple sclerosis glutathione reduced oxidized perioxidase glutathione-S-transferase glutathione peroxidase GSH GSSG SOD GST 8OHdG 8-hydroxy-2-deoxyguanosine oxidative stress

shared by Nathan Goodyear on 19 Mar 14 - No Cached
  • Nathan Goodyear on 19 Mar 14
     
    Relapsing remitting MS patients found to have in increased 8OHdG, reduced glutathione, reduced glutathione to oxidized glutathione ratio, super oxidized disumutase, glutathione reductase, and global oxidative stress.  In contrast, decreased total antioxidant capacity, oxidized glutathione, glutathione perioxidase, and glutathione transferase were found in relapsing remitting MS patients.
Nathan Goodyear

Effect of astaxanthin supplementation on muscle damage and oxidative stress markers in ... - 0 views

www.ncbi.nlm.nih.gov/...22828460

astaxanthin TBARS oxidative stress exercise soccer SOD antioxidant antioxidants

shared by Nathan Goodyear on 14 Jul 15 - No Cached
  • Postexercise CK and AST levels were significantly lower in Asx group compared to P group (P<0.05)
  • Nathan Goodyear on 14 Jul 15
     
    study finds soccer training is associated with increased oxidative stress as measured by TBARS, SOD, superoxide anion and other oxidative stress load biomarkers.  Astaxanthin was associated with less oxidative stress.
Nathan Goodyear

Toxicity of the spike protein of COVID-19 is a redox shift phenomenon: A novel therapeu... - 0 views

www.sciencedirect.com/...S0891584923005014

COVID19 COVID-19 cancer inflammation SARS-CoV-2 spike proteins COVID spikeopathy

shared by Nathan Goodyear on 01 Sep 23 - No Cached
  • Redox shift is due to Warburg effect and mitochondrial impairment.
  • Redox shift is due to Warburg effect and mitochondrial impairment.
  • Redox shift is due to Warburg effect and mitochondrial impairment.
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  • The cytokine storm is a consequence of mitochondrial dysfunction
  • The cytokine storm is a consequence of mitochondrial dysfunction
  • The cytokine storm is a consequence of mitochondrial dysfunction
  • The cytokine storm is a consequence of mitochondrial dysfunction
  • Lipoic acid, Methylene Blue and Chlorine dioxide relieve COVID-19 spike protein toxicity
  • Lipoic acid, Methylene Blue and Chlorine dioxide relieve COVID-19 spike protein toxicity
  • Lipoic acid, Methylene Blue and Chlorine dioxide relieve COVID-19 spike protein toxicity
  • Lipoic acid, Methylene Blue and Chlorine dioxide relieve COVID-19 spike protein toxicity
  • most diseases display a form of anabolism due to mitochondrial impairment
  • most diseases display a form of anabolism due to mitochondrial impairment
  • most diseases display a form of anabolism due to mitochondrial impairment
  • infection by Covid-19 follows a similar pattern
  • chronic inflammation
  • Long-term effects include redox shift and cellular anabolism as a result of the Warburg effect and mitochondrial dysfunction
  • Long-term effects include redox shift and cellular anabolism as a result of the Warburg effect and mitochondrial dysfunction
  • Long-term effects include redox shift and cellular anabolism as a result of the Warburg effect and mitochondrial dysfunction
  • Long-term effects include redox shift and cellular anabolism as a result of the Warburg effect and mitochondrial dysfunction
  • infection by Covid-19 follows a similar pattern
  • unrelenting anabolism leads to the cytokine storm,
  • unrelenting anabolism leads to the cytokine storm,
  • unrelenting anabolism leads to the cytokine storm,
  • chronic inflammation
  • chronic inflammation
  • infection by Covid-19 follows a similar pattern
  • Lipoic acid and Methylene Blue have been shown to enhance the mitochondrial activity, relieve the Warburg effect and increase catabolism
  • Lipoic acid and Methylene Blue have been shown to enhance the mitochondrial activity, relieve the Warburg effect and increase catabolism
  • Lipoic acid and Methylene Blue have been shown to enhance the mitochondrial activity, relieve the Warburg effect and increase catabolism
  • Methylene Blue, Chlorine dioxide and Lipoic acid may help reduce long-term Covid-19 effects by stimulating the catabolism
  • Methylene Blue, Chlorine dioxide and Lipoic acid may help reduce long-term Covid-19 effects by stimulating the catabolism
  • Methylene Blue, Chlorine dioxide and Lipoic acid may help reduce long-term Covid-19 effects by stimulating the catabolism
  • direct consequence of redox iMeBalance, itself a consequence of decreased energy yield by the mitochondria
  • direct consequence of redox iMeBalance, itself a consequence of decreased energy yield by the mitochondria
  • mitochondrial dysfunction and increased levels of lactate, which are important characteristics of metabolic shift and Warburg effect in many diseases
  • mitochondrial dysfunction and increased levels of lactate, which are important characteristics of metabolic shift and Warburg effect in many diseases
  • increased lactate dehydrogenase activity (LDH) was observed in COVID-19 patients
  • increased lactate dehydrogenase activity (LDH) was observed in COVID-19 patients
  • almost every disease presents an increased anabolism
  • almost every disease presents an increased anabolism
  • cell division is the most sophisticated way to release entropy
  • cell division is the most sophisticated way to release entropy
    • Nathan Goodyear
      Nathan Goodyear on 01 Sep 23
       
      Wow
    • Nathan Goodyear
      Nathan Goodyear on 01 Sep 23
       
      Wow
  • transition from catabolism to anabolism is driven by a redox shift
  • transition from catabolism to anabolism is driven by a redox shift
  • viral spike protein binds to ACE2 receptor of the host cell [22,23].
  • redox signaling plays an important role in regulating immune function and inflammation, and disruptions in this signaling can lead to excessive cytokine production and immune system activation
  • Aging is associated with a poor control of the redox balance
  • thiol/disulfide homeostasis
  • reduced extracellular environment in the elderly and the increased susceptibility to Covid-19 infection
  • reduced extracellular environment in the elderly and the increased susceptibility to Covid-19 infection
  • Redox signaling tightly modulates the inflammatory response and oxidative stress has been reported in acute Covid-19
  • People at high risk are the elderly, patients suffering from metabolic syndrome such as obesity, or those suffering from chronic diseases such as cancer or inflammation
  • COVID-19 patients with severe disease have higher levels of oxidative stress markers and lower antioxidant levels
  • oxidative stress can activate the NLRP3 inflammasome, which is a protein complex that plays a key role in the cytokine storm
  • inflammation leads to the formation of ROS and RNS, while redox iMeBalance results in cellular damage, which in turn triggers an inflammatory response
  • persistently elevated mtROS triggers endothelial dysfunction and inflammation, which results in a vicious loop involving ROS, inflammation, and mitochondrial dysfunction
  • Damaged mitochondria releasing ROS induce inflammation via the NLRP3 inflammasome
  • Damaged mitochondria releasing ROS induce inflammation via the NLRP3 inflammasome
  • reduced environment during the cytokine storm
  • IL-2 is highly up-regulated in Covid-19 patients [37], and IL-2 is known to significantly stimulate the generation of NO in patients
  • Nitric acid is also the key mediator of IL-2-induced hypotension and vascular leak syndrome
  • mitochondrial dysfunction has been linked to the pathogenesis of Covid-19
  • mitochondrial dysfunction triggered by SARS-CoV-2 leads to damage to the mitochondria
  • mitochondrial dysfunction triggered by SARS-CoV-2 leads to damage to the mitochondria
  • As catabolism is decreased, entropy is released through anabolism
  • Elevated levels of lactate, a characteristic of the Warburg effect, were also reported in the high-risk Covid-19
  • elevated levels of ventricular lactic acid consistent with oxidative stress
  • A decrease of ΔΨm is implicated in several inflammation-related diseases
  • decrease in ΔΨm in leucocytes from Covid-19 patients
  • vaccinated with RNA or DNA vaccines triggering the synthesis of the viral spike protein in human cells
  • viral reactivation in varicella-zoster virus [55] or hepatitis [56], coagulopathy and resulting stroke and myocarditis following both DNA-based vaccines [57] and RNA-based vaccines
  • Covid-19, mitochondrial impairment
  • characteristic of the Warburg effect is present in almost every disease and appears to be a central feature in most of the hallmarks of cancer
  • inflammation, mitochondrial dysfunction and increased lactate concentrations in the extracellular fluid
  • In Covid-19, like any inflammation, there is a metabolic rewiring where cells rely on glycolysis
  • As the mitochondria are impaired, the infected cell cannot catabolize efficiently. It will release lactic acid in the blood stream
    • Nathan Goodyear
      Nathan Goodyear on 01 Sep 23
       
      Mitochondrial impairment
  • Striking similarities are seen between cancer, Alzheimer's disease and Covid-19, all related to the Warburg effect
  • Cancer, inflammation, Alzheimer's, and Parkinson's diseases share a common peculiarity, the inability of the cell to export entropy outside the body in the harmless form of heat
    • Nathan Goodyear
      Nathan Goodyear on 01 Sep 23
       
      Entropy: lack of order or predictability; gradual decline into disorder.
  • MEB relieves the Warburg effect [87], improves memory [77], is active in the treatment of depressive episodes [79,80] and reduces the importance of ischemic strokes
  • MEB relieves the Warburg effect [87], improves memory [77], is active in the treatment of depressive episodes [79,80] and reduces the importance of ischemic strokes
  • MEB has been shown to inhibit SARS-Cov-2 replication in vitro
  • MEB has been shown to inhibit SARS-Cov-2 replication in vitro
  • It has been shown that Covid-19-patients treated with MEB, have a significant reduction in hospital stay duration and mortality
  • MeB is an acceptor-donor molecule
  • MeB + can take a pair of electrons (of H atoms) and MeBH can release this pair easily, so that MeB is partially recycled like a catalyst
  • MeB acts as an electron bridge between a donor (FADH2, FMNH, NADH) and an acceptor (complex IV of ETC or oxygen itself)
  • As a coenzyme of pyruvate dehydrogenase (PDH), alpha-lipoic acid (ALA) initiates the formation of acetyl-CoA to feed the TCA cycle
  • ALA enhances the catabolism of carbon. cycle and therefore may reduce the Warburg effect and consequently, lactate production
  • Methylene Blue plays a similar role after the TCA cycle, by carrying electrons to complex IV of the electron transport chain
  • Drugs such as lipoic acid and MeB, which target the metabolism, decrease the redox shift by increasing catabolism
Nathan Goodyear

Mitochondrial Fission Induces Glycolytic Reprogramming in Cancer-Associated Myofibrobla... - 0 views

www.ncbi.nlm.nih.gov/...PMC3478457

warburg effect Cancer cancer associated fibroblasts CAFs reverse warburg effect lactate aerobic glycolysis mitochondria oxidative stress ROS H2O2

shared by Nathan Goodyear on 11 Nov 14 - No Cached
  • L-lactate functions as an onco-metabolite, stimulating mitochondrial biogenesis and OXPHOS in adjacent cancer cells, directly providing energy for tumor growth
  • Oxidative stress in stromal fibroblasts then induces their metabolic conversion into cancer-associated fibroblasts. Such oxidative stress drives the onset of autophagy, mitophagy, and aerobic glycolysis in fibroblasts, resulting in the local production of high-energy mitochondrial fuels (such as L-lactate, ketone bodies, and glutamine). These recycled nutrients are then transferred to cancer cells, where they are efficiently burned via oxidative mitochondrial metabolism (OXPHOS)
  • stromal L-lactate serves as a high-energy mitochondrial “fuel” for cancer cells. We have termed this new model of cancer metabolism “Two-Compartment Tumor Metabolism”, where two opposing metabolic compartments co-exist, side-by-side, with stromal glycolysis fueling OXPHOS in cancer cells
  • ...10 more annotations...
  • Two-Compartment Tumor Metabolism
  • Reverse Warburg Effect”, is that catabolic fibroblasts should promote tumor growth, without any increases in angiogenesis
  • when cancer cells use L-lactate as a mitochondrial fuel source, this metabolic phenotype is a predictor of lethal cancer metabolism
  • tumor microenvironment is intimately involved in tumor development and progression
  • mitochondrial dysregulation is likely the “root cause” of several human disease(s), and especially epithelial cancers
  • Both in vitro and in vivo studies have now provided convincing evidence that “activated” stromal fibroblasts, a.k.a., myofibroblasts, may play a critical role in initiating tumor recurrence, via paracrine interactions with adjacent tumor epithelial cells
  • A new hypothesis is that cancer is not a cell autonomous disease, but rather a disease of the tumor microenvironment
  • cancer cells behave as metabolic parasites, by inducing oxidative stress in adjacent normal fibroblasts
  • recent experimental evidence indicates that cancer-associated fibroblasts have a catabolic phenotype, and undergo autophagy and mitophagy, resulting in the onset of glycolytic metabolism, driving L-lactate production, and its release into the tumor microenvironment
  • oncogenic mutations in cancer cells lead to ROS production and the “secretion” of hydrogen peroxide species
  • Nathan Goodyear on 11 Nov 14
     
    A good discussion of what is proposed the Reverse Warburg effect.  A process by which the local environment dictates tumor progression.  The cancer cells release ROS primarily in the form of H2O2 and this leads to Cancer Associated Fibroblasts (CAFs) in the stroma.  The altered stromal environment increases ROS further and promotes ocogenic metabolites through the classic Warburg effect.  This high lactate production from the CAFs then is used by the cancer cells via classic oxidative phosphorylation.  Complex, beautiful and still an the understanding is a work in progress.   This study/article points to the importance of oxidative stress in some cancer development through CAFs.
Nathan Goodyear

Pharmacological Ascorbate Radiosensitizes Pancreatic Cancer - 0 views

www.ncbi.nlm.nih.gov/...PMC4537815

cancer pancreatic cancer IV vitamin C vitamin c radiation

shared by Nathan Goodyear on 30 Jan 18 - No Cached
  • Previous studies from our laboratory have demonstrated that pharmacological ascorbate is cytotoxic to pancreatic cancer cells while normal cells are resistant
  • Ascorbate-induced cytotoxicity is mediated by the formation of H2O2 during the oxidation of ascorbate
  • the combination of IR + ascorbate increased the concentration of intracellular H2O2
  • ...17 more annotations...
  • Under steady-state conditions, intracellular GSH is maintained at millimolar concentrations, which keeps cells in a reduced environment and serves as the principal intracellular redox buffer when cells are subjected to an oxidative stressor including H2O2 (26). Glutathione peroxidase (GPx) activity catalyzes the reduction of H2O2 to water with the conversion of GSH to glutathione disulfide (GSSG). Under steady-state conditions, GSSG is recycled back to GSH by glutathione disulfide reductase using reducing equivalents from NADPH. However, under conditions of increased H2O2 flux, this recycling mechanism may become overwhelmed leading to a depletion of intracellular GSH (27, 28).
  • ascorbate radiosensitization can create an overwhelming oxidative stress to pancreatic cancer cells resulting in oxidation/depletion of the GSH intracellular redox buffer, resulting in cell death.
  • Treatment with the combination of ascorbate + IR significantly delayed tumor growth compared to controls or ascorbate alone
  • Ascorbate + IR also significantly increased overall survival compared to controls, IR alone or ascorbate alone
  • 54% of mice treated with the combination of IR + ascorbate had no measurable tumors
  • Glutathione is a measurable marker indicative of the oxidation state of the thiol redox buffer in cells. In severe systemic oxidative stress, the GSSG/2GSH couple may become oxidized, i.e. the concentration of GSH decreases and GSSG may increase because the capacity to recycle GSSG to GSH becomes rate-limiting
  • This suggests that the very high levels of pharmacological ascorbate in these experiments may have a pro-oxidant toward red blood cells as seen by a decrease in the capacity of the intracellular redox buffer
  • These data support the hypothesis that ascorbate radiosensitization does not cause an increase in oxidative damage from lipid-derived aldehydes to other organs.
  • Our current study demonstrates the potential for pharmacological ascorbate as a radiosensitizer in the treatment of pancreatic cancer.
  • pharmacological ascorbate enhances IR-induced cell killing and DNA fragmentation leading to induction of apoptosis in HL60 leukemia cells
  • pharmacological ascorbate significantly decreases clonogenic survival and inhibits the growth of all pancreatic cancer cell lines as a single agent, as well as sensitizes cancer cells to IR
  • Hurst et al. demonstrated that pharmacological ascorbate combined with IR leads to increased numbers of double-strand DNA breaks and cell cycle arrest when compared to either treatment alone
  • pharmacological ascorbate could serve as a “pro-drug” for the delivery of H2O2 to tumors
  • the double-strand breaks induced by H2O2 were more slowly repaired
  • The combination of ascorbate and IR provide two distinct mechanisms of action: ascorbate-induced toxicity due to extracellular production of H2O2 that then diffuses into cells and causes damage to DNA, protein, and lipids; and radiation-induced toxicity as a result of ROS-induced damage to DNA. In addition, redox metal metals like Fe2+ may play an important role in ascorbate-induced cytotoxicity. By catalyzing the oxidation of ascorbate, labile iron can enhance the rate of formation of H2O2; labile iron can also react with H2O2. Recently our group has demonstrated that pharmacological ascorbate and IR increase the labile iron in tumor homogenates from this murine model of pancreatic cancer
  • we demonstrated that ascorbate or IR alone decreased tumor growth, but the combination treatment further inhibited tumor growth, indicating that pharmacological ascorbate is an effective radiosensitizer in vivo
  • data suggest that pharmacological ascorbate may protect the gut locally by decreasing IR-induced damage to the crypt cells, and systemically, by ameliorating increases in TNF-α
  • Nathan Goodyear on 30 Jan 18
     
    IV vitamin C effective as radiosensitizer in pancreatic cancer.
Nathan Goodyear

Oxidative Stress, Testosterone, and Cognition among Caucasian and Mexican-American Men ... - 0 views

iospress.metapress.com/...t1717503235m8667

Testosterone alzheimer memory disease stress oxidative oxidative stress men male hormone hormones cognition

shared by Nathan Goodyear on 03 Mar 14 - No Cached
  • Nathan Goodyear on 03 Mar 14
     
    Interesting study. This study points out the differences between individuals and groups i.e. Mexian-Americans and Caucasians in this study.  Men with low oxidative stress, Testosterone was associated with no cognitive dysfunction.  In contrast, with high oxidative stress, Testosterone therapy was associated with cognitive impairment in caucasians only.
Nathan Goodyear

Press-pulse: a novel therapeutic strategy for the metabolic management of cancer | Nutr... - 0 views

nutritionandmetabolism.biomedcentral.com/...s12986-017-0178-2

ketogenic diet ketogenic press-pulse hyperbaric oxygen therapy HBOTnutrition diet cancer HBOT IVC IV vitamin C DCA dichloracetic acid cancer therapy cancer treatment alternative cancer treatment

shared by Nathan Goodyear on 09 Jul 17 - No Cached
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  • A “press” disturbance was considered a chronic environmental stress on all organisms in an ecological community
  • “pulse” disturbances were considered acute events that disrupted biological communities to produce high mortality
  • Neoplasia involving dysregulated cell growth is the biological endpoint of the disease
  • ...84 more annotations...
  • Data from the American Cancer Society show that the rate of increase in cancer deaths/year (3.4%) was two-fold greater than the rate of increase in new cases/year (1.7%) from 2013 to 2017
  • cancer is predicted to overtake heart disease as the leading cause of death in Western societies
  • cancer can also be recognized as a metabolic disease.
  • glucose is first split into two molecules of pyruvate through the Embden–Meyerhof–Parnas glycolytic pathway in the cytosol
  • Aerobic fermentation, on the other hand, involves the production of lactic acid under normoxic conditions
  • persistent lactic acid production in the presence of adequate oxygen is indicative of abnormal respiration
  • Otto Warburg first proposed that all cancers arise from damage to cellular respiration
  • The Crabtree effect is an artifact of the in vitro environment and involves the glucose-induced suppression of respiration with a corresponding elevation of lactic acid production even under hyperoxic (pO2 = 120–160 mmHg) conditions associated with cell culture
  • the Warburg theory of insufficient aerobic respiration remains as the most credible explanation for the origin of tumor cells [2, 37, 51, 52, 53, 54, 55, 56, 57].
  • The main points of Warburg’s theory are; 1) insufficient respiration is the predisposing initiator of tumorigenesis and ultimately cancer, 2) energy through glycolysis gradually compensates for insufficient energy through respiration, 3) cancer cells continue to produce lactic acid in the presence of oxygen, and 4) respiratory insufficiency eventually becomes irreversible
  • Efraim Racker coined the term “Warburg effect”, which refers to the aerobic glycolysis that occurs in cancer cells
  • Warburg clearly demonstrated that aerobic fermentation (aerobic glycolysis) is an effect, and not the cause, of insufficient respiration
  • all tumor cells that have been examined to date contain abnormalities in the content or composition of cardiolipin
  • The evidence supporting Warburg’s original theory comes from a broad range of cancers and is now overwhelming
  • respiratory insufficiency, arising from any number mitochondrial defects, can contribute to the fermentation metabolism seen in tumor cells.
  • data from the nuclear and mitochondrial transfer experiments suggest that oncogene changes are effects, rather than causes, of tumorigenesis
  • Normal mitochondria can suppress tumorigenesis, whereas abnormal mitochondria can enhance tumorigenesis
  • In addition to glucose, cancer cells also rely heavily on glutamine for growth and survival
  • Glutamine is anapleurotic and can be rapidly metabolized to glutamate and then to α-ketoglutarate for entry into the TCA cycle
  • Glucose and glutamine act synergistically for driving rapid tumor cell growth
  • Glutamine metabolism can produce ATP from the TCA cycle under aerobic conditions
  • Amino acid fermentation can generate energy through TCA cycle substrate level phosphorylation under hypoxic conditions
  • Hif-1α stabilization enhances aerobic fermentation
  • targeting glucose and glutamine will deprive the microenvironment of fermentable fuels
  • Although Warburg’s hypothesis on the origin of cancer has created confusion and controversy [37, 38, 39, 40], his hypothesis has never been disproved
  • Warburg referred to the phenomenon of enhanced glycolysis in cancer cells as “aerobic fermentation” to highlight the abnormal production of lactic acid in the presence of oxygen
  • Emerging evidence indicates that macrophages, or their fusion hybridization with neoplastic stem cells, are the origin of metastatic cancer cells
  • Radiation therapy can enhance fusion hybridization that could increase risk for invasive and metastatic tumor cells
  • Kamphorst et al. in showing that pancreatic ductal adenocarcinoma cells could obtain glutamine under nutrient poor conditions through lysosomal digestion of extracellular proteins
  • It will therefore become necessary to also target lysosomal digestion, under reduced glucose and glutamine conditions, to effectively manage those invasive and metastatic cancers that express cannibalism and phagocytosis.
  • Previous studies in yeast and mammalian cells show that disruption of aerobic respiration can cause mutations (loss of heterozygosity, chromosome instability, and epigenetic modifications etc.) in the nuclear genome
  • The somatic mutations and genomic instability seen in tumor cells thus arise from a protracted reliance on fermentation energy metabolism and a disruption of redox balance through excess oxidative stress.
  • According to the mitochondrial metabolic theory of cancer, the large genomic heterogeneity seen in tumor cells arises as a consequence, rather than as a cause, of mitochondrial dysfunction
  • A therapeutic strategy targeting the metabolic abnormality common to most tumor cells should therefore be more effective in managing cancer than would a strategy targeting genetic mutations that vary widely between tumors of the same histological grade and even within the same tumor
  • Tumor cells are more fit than normal cells to survive in the hypoxic niche of the tumor microenvironment
  • Hypoxic adaptation of tumor cells allows for them to avoid apoptosis due to their metabolic reprograming following a gradual loss of respiratory function
  • The high rates of tumor cell glycolysis and glutaminolysis will also make them resistant to apoptosis, ROS, and chemotherapy drugs
  • Despite having high levels of ROS, glutamate-derived from glutamine contributes to glutathione production that can protect tumor cells from ROS
    • Nathan Goodyear
      Nathan Goodyear on 08 Feb 18
       
      reason to eliminate glutamine in cancer patients and even GSH with cancer patients
  • It is clear that adaptability to environmental stress is greater in normal cells than in tumor cells, as normal cells can transition from the metabolism of glucose to the metabolism of ketone bodies when glucose becomes limiting
  • Mitochondrial respiratory chain defects will prevent tumor cells from using ketone bodies for energy
  • glycolysis-dependent tumor cells are less adaptable to metabolic stress than are the normal cells. This vulnerability can be exploited for targeting tumor cell energy metabolism
  • In contrast to dietary energy reduction, radiation and toxic drugs can damage the microenvironment and transform normal cells into tumor cells while also creating tumor cells that become highly resistant to drugs and radiation
  • Drug-resistant tumor cells arise in large part from the damage to respiration in bystander pre-cancerous cells
  • Because energy generated through substrate level phosphorylation is greater in tumor cells than in normal cells, tumor cells are more dependent than normal cells on the availability of fermentable fuels (glucose and glutamine)
  • Ketone bodies and fats are non-fermentable fuels
  • Although some tumor cells might appear to oxidize ketone bodies by the presence of ketolytic enzymes [181], it is not clear if ketone bodies and fats can provide sufficient energy for cell viability in the absence of glucose and glutamine
  • Apoptosis under energy stress is greater in tumor cells than in normal cells
  • A calorie restricted ketogenic diet or dietary energy reduction creates chronic metabolic stress in the body
  • . This energy stress acts as a press disturbance
  • Drugs that target availability of glucose and glutamine would act as pulse disturbances
  • Hyperbaric oxygen therapy can also be considered another pulse disturbance
  • The KD can more effectively reduce glucose and elevate blood ketone bodies than can CR alone making the KD potentially more therapeutic against tumors than CR
  • Campbell showed that tumor growth in rats is greater under high protein (>20%) than under low protein content (<10%) in the diet
  • Protein amino acids can be metabolized to glucose through the Cori cycle
  • The fats in KDs used clinically also contain more medium chain triglycerides
  • Calorie restriction, fasting, and restricted KDs are anti-angiogenic, anti-inflammatory, and pro-apoptotic and thus can target and eliminate tumor cells through multiple mechanisms
  • Ketogenic diets can also spare muscle protein, enhance immunity, and delay cancer cachexia, which is a major problem in managing metastatic cancer
  • GKI values of 1.0 or below are considered therapeutic
  • The GKI can therefore serve as a biomarker to assess the therapeutic efficacy of various diets in a broad range of cancers.
  • It is important to remember that insulin drives glycolysis through stimulation of the pyruvate dehydrogenase complex
  • The water-soluble ketone bodies (D-β-hydroxybutyrate and acetoacetate) are produced largely in the liver from adipocyte-derived fatty acids and ketogenic dietary fat. Ketone bodies bypass glycolysis and directly enter the mitochondria for metabolism to acetyl-CoA
  • Due to mitochondrial defects, tumor cells cannot exploit the therapeutic benefits of burning ketone bodies as normal cells would
  • Therapeutic ketosis with racemic ketone esters can also make it feasible to safely sustain hypoglycemia for inducing metabolic stress on cancer cells
    • Nathan Goodyear
      Nathan Goodyear on 08 Feb 18
       
      Ketones are much more than energy adaptabilit, but actually are therapeutic.
  • ketone bodies can inhibit histone deacetylases (HDAC) [229]. HDAC inhibitors play a role in targeting the cancer epigenome
  • Therapeutic ketosis reduces circulating inflammatory markers, and ketones directly inhibit the NLRP3 inflammasome, an important pro-inflammatory pathway linked to carcinogenesis and an important target for cancer treatment response
  • Chronic psychological stress is known to promote tumorigenesis through elevations of blood glucose, glucocorticoids, catecholamines, and insulin-like growth factor (IGF-1)
  • In addition to calorie-restricted ketogenic diets, psychological stress management involving exercise, yoga, music etc. also act as press disturbances that can help reduce fatigue, depression, and anxiety in cancer patients and in animal models
  • Ketone supplementation has also been shown to reduce anxiety behavior in animal models
  • This physiological state also enhances the efficacy of chemotherapy and radiation therapy, while reducing the side effects
  • lower dosages of chemotherapeutic drugs can be used when administered together with calorie restriction or restricted ketogenic diets (KD-R)
  • Besides 2-DG, a range of other glycolysis inhibitors might also produce similar therapeutic effects when combined with the KD-R including 3-bromopyruvate, oxaloacetate, and lonidamine
    • Nathan Goodyear
      Nathan Goodyear on 08 Feb 18
       
      oxaloacetate is a glycolytic inhibitor, as is doxycycline, and IVC.
  • A synergistic interaction of the KD diet plus radiation was seen
  • It is important to recognize, however, that the radiotherapy used in glioma patients can damage the respiration of normal cells and increase availability of glutamine in the microenvironment, which can increase risk of tumor recurrence especially when used together with the steroid drug dexamethasone
  • Poff and colleagues demonstrated that hyperbaric oxygen therapy (HBOT) enhanced the ability of the KD to reduce tumor growth and metastasis
  • HBOT also increases oxidative stress and membrane lipid peroxidation of GBM cells in vitro
  • The effects of the KD and HBOT can be enhanced with administration of exogenous ketones, which further suppressed tumor growth and metastasis
  • Besides HBOT, intravenous vitamin C and dichloroacetate (DCA) can also be used with the KD to selectively increase oxidative stress in tumor cells
  • Recent evidence also shows that ketone supplementation may enhance or preserve overall physical and mental health
  • Some tumors use glucose as a prime fuel for growth, whereas other tumors use glutamine as a prime fuel [102, 186, 262, 263, 264]. Glutamine-dependent tumors are generally less detectable than glucose-dependent under FDG-PET imaging, but could be detected under glutamine-based PET imaging
  • GBM and use glutamine as a major fuel
  • Many of the current treatments used for cancer management are based on the view that cancer is a genetic disease
  • Emerging evidence indicates that cancer is a mitochondrial metabolic disease that depends on availability of fermentable fuels for tumor cell growth and survival
  • Glucose and glutamine are the most abundant fermentable fuels present in the circulation and in the tumor microenvironment
  • Low-carbohydrate, high fat-ketogenic diets coupled with glycolysis inhibitors will reduce metabolic flux through the glycolytic and pentose phosphate pathways needed for synthesis of ATP, lipids, glutathione, and nucleotides
  • Nathan Goodyear on 09 Jul 17
     
    Cancer is a mitochondrial disease? So says the well published Dr Seyfried. Glucose and glutamine drive cancer growth.
fitspresso

https://www.sightcare-co.com/ - 0 views

www.sightcare-co.com

sight care sightcare group training nearsightedness food for eyesight carey codd vitasight vision how to cure bad eye tips fix improve your red light eyes diet improvement skincare malaysia costos de medicare indonesia singapore eyecare

shared by fitspresso on 27 Sep 23 - No Cached
  • fitspresso on 27 Sep 23
     
    Sight Care | Official Site sightcare-co.com · by Sight Care Sight Care Only $49/Bottle Limited Time Offer! Sight Care Special Deal + Special 67% Discount Save $600 + 180 Days Money Back Guarantee #1.The Sight Care vision supplement is a dietary supplement for helping you improve your vision and brain health. Sight Care eye supplements are formulated to provide a synergistic blend of vitamins, minerals, antioxidants, and other bioactive compounds that are essential for maintaining healthy vision Regular Price: 147/per bottle Only for: $49/per bottle What Is Sight Care? This powerful vision support supplement is made with a unique blend of natural ingredients and plant extracts that work together synergistically to deliver numerous benefits for your brain and eye health. With Sight Care, you can expect to experience increased energy levels, improved eyesight, and an overall revitalized sense of well-being. Taking care of your vision health is not just about seeing clearly; it's also about maintaining your overall brain health. As we age, our vision deteriorates, and our eyes and brain can experience a decline in function, but there are steps you can take to support your visual and cognitive health. Regular eye exams are crucial for detecting and treating vision problems early on, and making healthy choices such as eating a nutritious diet and exercising regularly can also help. However, with busy schedules, it can be difficult to find the time to devote to a healthy lifestyle. This is where the Sight Care supplement comes in. It's designed to support both vision and brain health with its blend of natural ingredients that have been shown to promote healthy vision and cognitive function You must not compromise your eye health for momentary exhilaration. If you are glued to digital screens day and night, you must take measures to prevent eye diseases like age-related macular degeneration. The SightCare vision supplement has been made using 100% natura
Nathan Goodyear

Lipid Peroxidation: Production, Metabolism, and Signaling Mechanisms of Malondialdehyde... - 0 views

www.hindawi.com/...360438

MDA malondialdehyde peroxidation oxidative stress free radicals

shared by Nathan Goodyear on 05 Dec 17 - No Cached
  • Hydroxyl radicals cause oxidative damage to cells because they unspecifically attack biomolecules [22] located less than a few nanometres from its site of generation and are involved in cellular disorders such as neurodegeneration [23, 24], cardiovascular disease [25], and cancer [26, 27].
  • It is generally assumed that in biological systems is formed through redox cycling by Fenton reaction, where free iron (Fe2+) reacts with hydrogen peroxide (H2O2) and the Haber-Weiss reaction that results in the production of Fe2+ when superoxide reacts with ferric iron (Fe3+)
  • other transition-metal including Cu, Ni, Co, and V can be responsible for formation in living cells
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  • The hydroperoxyl radical () plays an important role in the chemistry of lipid peroxidation
  • The is a much stronger oxidant than superoxide anion-radical
  • Lipid peroxidation can be described generally as a process under which oxidants such as free radicals or nonradical species attack lipids containing carbon-carbon double bond(s), especially polyunsaturated fatty acids (PUFAs) that involve hydrogen abstraction from a carbon, with oxygen insertion resulting in lipid peroxyl radicals and hydroperoxides as described previously
  • under medium or high lipid peroxidation rates (toxic conditions) the extent of oxidative damage overwhelms repair capacity, and the cells induce apoptosis or necrosis programmed cell death
  • The overall process of lipid peroxidation consists of three steps: initiation, propagation, and termination
  • Once lipid peroxidation is initiated, a propagation of chain reactions will take place until termination products are produced.
  • The main primary products of lipid peroxidation are lipid hydroperoxides (LOOH)
  • Among the many different aldehydes which can be formed as secondary products during lipid peroxidation, malondialdehyde (MDA), propanal, hexanal, and 4-hydroxynonenal (4-HNE) have been extensively studied
  • MDA has been widely used for many years as a convenient biomarker for lipid peroxidation of omega-3 and omega-6 fatty acids because of its facile reaction with thiobarbituric acid (TBA)
  • MDA is one of the most popular and reliable markers that determine oxidative stress in clinical situations [53], and due to MDA’s high reactivity and toxicity underlying the fact that this molecule is very relevant to biomedical research community
  • 4-HNE is considered as “second toxic messengers of free radicals,” and also as “one of the most physiologically active lipid peroxides,” “one of major generators of oxidative stress,” “a chemotactic aldehydic end-product of lipid peroxidation,” and a “major lipid peroxidation product”
  • MDA is an end-product generated by decomposition of arachidonic acid and larger PUFAs
  • Identifying in vivo MDA production and its role in biology is important as indicated by the extensive literature on the compound (over 15 800 articles in the PubMed database using the keyword “malondialdehyde lipid peroxidation” in December 2013)
  • MDA reactivity is pH-dependent
  • When pH decreases MDA exists as beta-hydroxyacrolein and its reactivity increases
  • MAA adducts are shown to be highly immunogenic [177–181]. MDA adducts are biologically important because they can participate in secondary deleterious reactions (e.g., crosslinking) by promoting intramolecular or intermolecular protein/DNA crosslinking that may induce profound alteration in the biochemical properties of biomolecules and accumulate during aging and in chronic diseases
  • MDA is an important contributor to DNA damage and mutation
  • This MDA-induced DNA alteration may contribute significantly to cancer and other genetic diseases.
  • Dietary intake of certain antioxidants such as vitamins was associated with reduced levels of markers of DNA oxidation (M1dG and 8-oxodG) measured in peripheral white blood cells of healthy subjects, which could contribute to the protective role of vitamins on cancer risk
  • 4-HNE is an extraordinarily reactive compound
  • Nathan Goodyear on 05 Dec 17
     
    Great review of lipid peroxidation
Nathan Goodyear

Metabolic management of brain cancer - 0 views

www.sciencedirect.com/...S0005272810006857

brain cancer

shared by Nathan Goodyear on 17 Jun 13 - No Cached
  • Glutamine is a major metabolic fuel for both brain tumor cells and tumor-associated macrophages (TAMs)
  • the malignant phenotype of brain tumor cells that survive radiotherapy is often greater than that of the cells from the original tumor.
  • Conventional chemotherapy has faired little better than radiation therapy for the long-term management of malignant brain cancer
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  • most conventional radiation and brain cancer chemotherapies can enhance glioma energy metabolism and invasive properties, which would contribute to tumor recurrence and reduced patient survival [34].
  • We contend that all cancer regardless of tissue or cellular origin is a disease of abnormal energy metabolism
  • complex disease phenotypes can be managed through self-organizing networks that display system wide dynamics involving oxidative and non-oxidative (substrate level) phosphorylation
  • As long as brain tumors are provided a physiological environment conducive for their energy needs they will survive; when this environment is restricted or abruptly changed they will either grow slower, growth arrest, or perish [8] and [19]
  • New information also suggests that ketones are toxic to some human tumor cells and that ketones and ketogenic diets might restrict availability of glutamine to tumor cells [68], [69] and [70].
  • The success in dealing with environmental stress and disease is therefore dependent on the integrated action of all cells in the organism
  • Tumor cells survive in hypoxic environments not because they have inherited genes making them more fit or adaptable than normal cells, but because they have damaged mitochondria and have thus acquired the ability to derive energy largely through substrate level phosphorylation
  • Cancer cells survive and multiply only in physiological environments that provide fuels (mostly glucose and glutamine) subserving their requirement for substrate level phosphorylation
  • Integrity of the inner mitochondrial membrane is necessary for ketone body metabolism since β-hydroxybutyrate dehydrogenase, which catalyzes the first step in the metabolism of β-OHB to acetoacetate, interacts with cardiolipin and other phospholipids in the inner membrane
  • the mitochondria of many gliomas and most tumors for that matter are dysfunctional
  • Cardiolipin is essential for efficient oxidative energy production and mitochondrial function
  • Any genetic or environmental alteration in the content or composition of cardiolipin will compromise energy production through oxidative phosphorylation
  • The Crabtree effect involves the inhibition of respiration by high levels of glucose
  • the Warburg effect involves elevated glycolysis from impaired oxidative phosphorylation
  • the Crabtree effect can be reversible, the Warburg effect is largely irreversible because its origin is with permanently damaged mitochondria
  • The continued production of lactic acid in the presence of oxygen is the metabolic hallmark of most cancers and is referred to as aerobic glycolysis or the Warburg effect
  • We recently described how the retrograde signaling system could induce changes in oncogenes and tumor suppressor genes to facilitate tumor cell survival following mitochondrial damage [48].
  • In addition to glycolysis, glutamine can also increase ATP production under hypoxic conditions through substrate level phosphorylation in the TCA cycle after its metabolism to α-ketoglutarate
  • mitochondrial lipid abnormalities, which alter electron transport activities, can account in large part for the Warburg effect
  • targeting both glucose and glutamine metabolism could be effective for managing most cancers including brain cancer
  • The bulk of experimental evidence indicates that mitochondria are dysfunctional in tumors and incapable of generating sufficient ATP through oxidative phosphorylation
  • Cardiolipin defects in tumor cells are also associated with reduced activities of several enzymes of the mitochondrial electron transport chain making it unlikely that tumor cells with cardiolipin abnormalities can generate adequate energy through oxidative phosphorylation
  • The Crabtree effect involves the inhibition of respiration by high levels of glucose
  • Warburg effect involves elevated glycolysis from impaired oxidative phosphorylation
  • TCA cycle substrate level phosphorylation could therefore become another source of ATP production in tumor cells with impairments in oxidative phosphorylation
  • Caloric restriction, which lowers glucose and elevates ketone bodies [63] and [64], improves mitochondrial respiratory function and glutathione redox state in normal cells
  • DR naturally inhibits glycolysis and tumor growth by lowering circulating glucose levels, while at the same time, enhancing the health and vitality of normal cells and tissues through ketone body metabolism
  • DR is anti-angiogenic
  • DR also reduces angiogenesis in prostate and breast cancer
  • We suggest that apoptosis resistance arises largely from enhanced substrate level phosphorylation of tumor cells and to the genes associated with elevated glycolysis and glutaminolysis, e.g., c-Myc, Hif-1a, etc, which inhibit apoptosis
  • Modern medicine has not looked favorably on diet therapies for managing complex diseases especially when well-established procedures for acceptable clinical practice are available, regardless of how ineffective these procedures might be in managing the disease
  • More than 60 years of clinical research indicates that such approaches are largely ineffective in extending survival or improving quality of life
  • The process is rooted in the well-established scientific principle that tumor cells are largely dependent on substrate level phosphorylation for their survival and growth
  • Glucose and glutamine drive substrate level phosphorylation
  • targeting the glycolytically active tumor cells that produce pro-cachexia molecules, restricted diet therapies can potentially reduce tumor cachexia
  • It is important to recognize, however, that “more is not better” with respect to the ketogenic diet
  • Blood glucose ranges between 3.0 and 3.5 mM (55–65 mg/dl) and β-OHB ranges between 4 and 7 mM should be effective for tumor management
  • Nathan Goodyear on 17 Jun 13
     
    Dr Seyfriend presents his metabolic approach to the treatment of brain cancer.
Nathan Goodyear

Oxidative stress and neurodegeneration: where are we now? - Halliwell - 2006 - Journal ... - 0 views

onlinelibrary.wiley.com/...full

oxidative damage oxidative stress detoxification CNS neurodegeneration neurodegenerative disease Free radicals Alzheimer's Parkinson's disease ALS MS

shared by Nathan Goodyear on 29 Oct 12 - No Cached
  • Nathan Goodyear on 29 Oct 12
     
    Fantastic review of oxidative damage and the CNS.  This is a 2006 review of our understanding of how neurodegeneration occurs through oxidative stress and of course poor detoxification.
Nathan Goodyear

Positive effects of astaxanthin on lipid profiles and oxidative stress in overweight su... - 0 views

www.ncbi.nlm.nih.gov/...21964877

astaxanthin MDA malondialdehyde oxidative stress SOD superoxide disumutase oxidized LDL LDL LDL cholesterol CVD

shared by Nathan Goodyear on 14 Jul 15 - No Cached
  • Nathan Goodyear on 14 Jul 15
     
    Astaxanthin at 20 mg found to reduce oxidized LDL and other oxidative stress biomarkers as assessed by Malondialdehydy, SOD, Isoprostane, and TAC.  The dose was 20 mg for 12 weeks. This higher dose was associated with minimal side effects--red stools.
Nathan Goodyear

JAMA Network | Archives of Neurology | Damage to Lipids, Proteins, DNA, and RNA in Mild... - 0 views

archneur.jamanetwork.com/article.aspx

neurodegenerative disease free-radicals Alzheimer's disease Alzheimer's oxidative stress oxidative damage lipid peroxides isoprostanes 8-hydroxy-2-deoxyguanosine neurology

shared by Nathan Goodyear on 13 Jun 12 - No Cached
  • Nathan Goodyear on 13 Jun 12
     
    oxidative damage found to be present in early Alzheimer's disease.  This early mild cognitive impairment is the time for treatment to delay disease progression.  As this study points out, most studies up to this point have been done on individuals with late Alzheimer's disease.  This show that oxidative damage plays a prominent role in disease development.  This study found oxidative damage through several markers: lipid peroxides,isoprostanes, 8-hydroxy-2-deoxyguanosine...
Nathan Goodyear

Chronic stress impacts the cardiovascular system: animal models and clinical outcomes |... - 0 views

ajpheart.physiology.org/...H1476

chronic stress stress inflammation cardiovascular disease atherosclerosis NO nitric oxide oxidative stress cardiovascular heart

shared by Nathan Goodyear on 03 Sep 17 - No Cached
  • Nathan Goodyear on 03 Sep 17
     
    Chronic stress increases cardiovascular disease.  Of note, chronic stress reduces eNOS activity and NO bioavailability, increased lipid oxidation (oxLDL) via a reduction in antioxidant protection, increased pro-inflammatory cytokines, increased thrombosis and clotting risk, increased blood pressure and reduced HRV.
Nathan Goodyear

Oxidative Stress and Stress-Activated Signaling Pathways: A Unifying Hypothesis of Type... - 0 views

edrv.endojournals.org/...599.long

free radicals oxidative stress damage inflammation type II DM alpha lipoic acid alpha-lipoic-acid diabetes

shared by Nathan Goodyear on 02 Aug 12 - No Cached
  • In patients with diabetes, LA levels are reduced (48, 74, 103). LA has long been used for the treatment of diabetic neuropathy in Germany
  • evidence indicates that it increases insulin sensitivity in patients with type 2 diabetes
  • LA has been shown to 1) quench free radicals, 2) prevent singlet oxygen-induced DNA damage, 3) exhibit chelating activity, 4) reduce lipid peroxidation, 5) increase intracellular glutathione levels, and 6) prevent glycation of serum albumin (73, 74). LA is able to reduce oxidative stress-mediated NF-κB activation in vitro (74, 108, 109) and in patients with type 2 diabetes
  • ...2 more annotations...
  • Activation of NF-κB can also be blocked by several other thiol-containing antioxidants including N-acetyl-l-cysteine (NAC)
  • Other clinically available antioxidants reported to have antiinflammatory, antioncogenic, and/or antiatherogenic properties that have been shown to block the activation of NF-κB include resveratrol (115, 116), (-)-epicatechin-3-gallate (117), pycnogenol (118), silymarin (119), and curcumin (120)
  • Nathan Goodyear on 02 Aug 12
     
    Great read!  If you want to see how free radicals and oxidative stress contribute to inflammation and disease (DM in this case), read this article.
Nathan Goodyear

Polysaccharides from Cordyceps sinensis mycelium ... [Pharm Biol. 2014] - PubMed - NCBI - 0 views

www.ncbi.nlm.nih.gov/...24047103

Cordyceps Cordyceps sinensis exercise performance oxidative stress

shared by Nathan Goodyear on 27 Jan 14 - No Cached
  • Nathan Goodyear on 27 Jan 14
     
    Mouse model finds that Cordyceps increased the interval to exhaustive exercise induced oxidative stress.  SOD, Cat, and GPx were increased in the low, intermediate, and high dose Cordyceps groups.  Oxidative stress markers MDA and 8-OHdG were lower in all groups
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