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Nathan Goodyear

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

  • 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
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  • 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 [
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    Great article chronicles the biochemistry of "over nutrition" and inflammation through NF-kappaB activation and its impact on the brain.
Nathan Goodyear

Aging and Luteinizing Hormone Effects on Reactive Oxygen Species Production and DNA Dam... - 0 views

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    Interesting rat model finds that stimulation of the leydig cells of the testis by LH induces ROS.  May be one of the mechanisms by which androgen therapy will induce long-term requirement for replacement.
Wayne Hartunian

GREAT Nutritional Products At Affordable Prices - 0 views

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    Joy To Live Has 10 Great Products to choose fromAnd They Are All The Same GREAT Price ( 22 Dollars )To Make It Easy For You To Start Your Home Business Fulvia, - ( Our Teams Favorite Product ) LeJOYva Coffee Aerobia® Oxygen Supplement EliXir Blast® Complete Nutritional Supplement Neutra-Cleanse® Digestive Support Capsule Optimum-Weight Loss® - ( Another Team Favorite ) Ionic Silver® Affinity® - ( Another Team Favorite ) Lissome® Anti-Aging Skin Serum JTL Dental Whitening System
Nathan Goodyear

Endothelial dysfunction of rat coronary arteries after exposure to low concentrations o... - 0 views

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    low dose, chronic exposure induces ROS and decreased NO availability.  This decrease in NO will result in increase vasoconstriction.  This will have localized effects and will result in increased central pressure as a result of the increased peripheral pressure.  In addition, inhibition of COMT will result in increase in catecholeamines.
Nathan Goodyear

Chronic Inflammation and Cytokines in the Tumor Microenvironment - 0 views

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    Acute inflammation is a response to an alteration induced by a pathogen or a physical or chemical insult, which functions to eliminate the source of the damage and restore homeostasis to the affected tissue. However, chronic inflammation triggers cellular events that can promote malignant transformation of cells and carcinogenesis. Several inflammatory mediators, such as TNF-α, IL-6, TGF-β, and IL-10, have been shown to participate in both the initiation and progression of cancer. In this review, we explore the role of these cytokines in important events of carcinogenesis, such as their capacity to generate reactive oxygen and nitrogen species, their potential mutagenic effect, and their involvement in mechanisms for epithelial mesenchymal transition, angiogenesis, and metastasis. Finally, we will provide an in-depth analysis of the participation of these cytokines in two types of cancer attributable to chronic inflammatory disease: colitis-associated colorectal cancer and cholangiocarcinoma.
wheelchairindia9

Cp Child Wheelchair - 0 views

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    young children have a different set of needs than adults. Aesthetically, devices designed for kids are often sleek and colorful, and functionally, they are typically lightweight and adjustable. As any parent knows, young people don't stay the same size for long and since a wheelchair is a major purchase -- don't want a simple growth spurt to render it useless. Wheelchair category offers models that feature seat width and depth adjustability, elevating legrests, and other versatile features. As a weight-bearing activity is critical to proper physical and mental function-which is why children with cerebral palsy, who may sit for stretches in a wheelchair and typically are unable to stand on their own, can benefit greatly from pediatric standers as part of a comprehensive pediatric rehabilitation program. Pediatric standers are offered in passive, active and mobile formats: Passive standers stay in one place and feature a support surface, active standers allow reciprocal movement of the extremities while in a standing position, and mobile standers enable users to self-propel. Cerebral Palsy Wheelchair: Cerebral Palsy Wheelchair Description: The model designed for cerebral palsy child only. Ultra light weight aluminium alloy frame. Seat Width 38 cms (15"). Net Weight: 18.5 kgs. Epoxy powder coated frame. Detachable arm rest & foot rest provided. Elevated and swinging foot rest. Elevated foot rest provided to elevate leg angle. Height adjustable and detachable head rest. Hydraulic reclining high back for a comfortable posture. Hydraulic adjustable seat angle. Detachable back and seat pad. Extra cushion upholstery provided to under arm, head & calg Foldable. Lever and paddle brakes provided. Safety belt provided. Maintenance free rear solid wheels. Cloth look like water proof upholstery. Anti wheels for better safety and stability. Extra cushion upholstery provided to under arm, head & leg. Folding action. Lever and paddle brakes provide
wheelchairindia9

Chair For Cerebral Palsy Child - 0 views

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    Cerebral palsy (CP) is a group of conditions caused by medical abnormalities in the development of a fetus or the early life of a child. These lead to damage or delayed development in the brain. The disorder is permanent and, though it does not worsen with age, the level of functionality of a person with cerebral palsy varies widely: in some cases, effects may be very minor, while in others, movement is impaired to the extent that a wheelchair is required. Common complications associated with CP vary by the type of CP disorder but can include vision problems, seizures, learning disabilities, and issues speaking, writing, and performing other tasks. Cerebral palsy causes problems with muscle tone, movement, balance and/or coordination. Symptoms and effects range from mild to severe. In some infants, problems are evident soon after birth. In others, diagnosis comes in later infancy or toddlerhood. Cerebral Palsy Wheelchair Description: The model designed for cerebral palsy child only. Ultra light weight aluminium alloy frame. Seat Width 38 cms (15"). Net Weight: 18.5 kgs. Epoxy powder coated frame. Detachable arm rest & foot rest provided. Elevated and swinging foot rest. Elevated foot rest provided to elevate leg angle. Height adjustable and detachable head rest. Hydraulic reclining high back for a comfortable posture. Hydraulic adjustable seat angle. Detachable back and seat pad. Extra cushion upholstery provided to under arm, head & calg Foldable. Lever and paddle brakes provided. Safety belt provided. Maintenance free rear solid wheels. Cloth look like water proof upholstery. Anti wheels for better safety and stability. Extra cushion upholstery provided to under arm, head & leg Folding action. Lever and paddle brakes provided. Safety belt provided. Maintenance free rear solid wheels. Cerebral Palsy Wheelchair Recline system: Recline system provides kids with the most comfortable resting environment. It also allows stretching abdomin
Nathan Goodyear

Urinary Estrogens and Estrogen Metabolites and Subsequent Risk of Breast Cancer among P... - 0 views

  • both 2- and 4-catechol estrogen metabolites bind to the ER with affinities comparable with estradiol, 4-catechol estrogen metabolites have lower dissociation rates than estradiol and an enhanced ability to upregulate ER-dependent processes
  • 2-catechol estrogen metabolites act as either weak mitogens (39) or weak inhibitors of cell proliferation
  • While 16α-hydroxyestrone binds to the ER with lower affinity than estradiol, it binds covalently (41) and leads to a constitutively activated ER
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  • 4-hydroxyestradiol and 16α-hydroxyestrone increasing proliferation and decreasing apoptosis in a manner similar to estradiol; however, these effects were achieved only at concentrations 10-fold higher than estradiol (39). In contrast, 2-hydroxyestradiol did not have substantial proliferative or antiapoptotic effects
  • In our study, the associations with both 2-hydroxyestrone and 16α-hydroxyestrone were nonsignificantly inverse and we did not observe a consistent trend or significant associations between the 2-hydroxyestrone:16α-hydroxyestrone ratio and breast cancer risk
  • Ratios of the 3 hydroxylation pathways were not significantly associated with risk although the 2:16-pathway and 4:16-pathway ratios were suggestively inversely associated
  • a significant inverse association with the ratio of parent estrogens to estrogen metabolites
  • several potentially estrogenic and genotoxic mechanisms
  • Estrogen metabolites also can be genotoxic
  • Catechol estrogens can be oxidized into quinones and induce DNA damage directly through the formation of DNA adducts, or indirectly via redox cycling and generation of reactive oxygen species
  • the oxidized forms of the catechol estrogens differ in their ability to damage DNA through adducts, with oxidized 2-catechols forming stable and reversible DNA adducts and oxidized 4-catechols forming unstable adducts, which lead to depurination and mutations
  • 2- and 4-catechols have been shown to produce reactive oxygen species and induce oxidative DNA damage
  • act independently from the ER
  • 16α-Hydroxyestrone also may be genotoxic
  • While the catechol estrogens have estrogenic and genotoxic potential, the methylated catechol estrogens, which are catechol estrogens with one hydroxyl group methylated, have been hypothesized to lower the risk of breast cancer
  • The suggested mechanisms are indirect, by decreasing circulating levels of catechol estrogens and thereby the opportunity for catechols to exert genotoxic or proliferative effects, or direct, by inhibiting tumor growth and inducing apoptosis
  • the balance between phase I (oxidation) and phase II (methylation) metabolism of estrogen may be important in hormonally related cancer development.
  • Despite the estrogenic and genotoxic potential of many of the estrogen metabolites, we only observed a significantly increased breast cancer risk with one estrogen metabolite, 17-epiestriol, which has particularly strong estrogenic activity and binds to both ERα and ERβ with an affinity comparable with estradiol
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    review of estrogen metabolites and breast cancer risk in premenopausal women.
Nathan Goodyear

Urinary estrogens and estrogen metabolites and subsequent risk of breast cancer among p... - 0 views

  • While the catechol estrogens have estrogenic and genotoxic potential, the methylated catechol estrogens, which are catechol estrogens with one hydroxyl group methylated, have been hypothesized to lower risk of breast cancer.
  • Despite the estrogenic and genotoxic potential of many of the EM, we only observed a significantly increased breast cancer risk with one EM, 17-epiestriol, which has particularly strong estrogenic activity and binds to both ERα and ERβ with an affinity comparable to estradiol
  • We did not observe reduced risk for higher concentrations of 2-pathway EM relative to 16-pathway EM, nor did we observe a consistent benefit of higher concentrations of methylated catechol EM compared with catechol EM.
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  • EM also can be genotoxic, but the individual EM vary in their ability to induce DNA damage
  • Catechol estrogens can be oxidized into quinones and induce DNA damage directly through the formation of DNA adducts, or indirectly via redox cycling and generation of reactive oxygen species
  • the oxidized forms of the catechol estrogens differ in their ability to damage DNA through adducts, with oxidized 2-catechols forming stable and reversible DNA adducts and oxidized 4-catechols forming unstable adducts, which lead to depurination and mutations
  • 2- and 4-catechols have been shown to produce reactive oxygen species and induce oxidative DNA damage (46). These catechols also induce neoplastic transformation in ER-cells, and thus act independently from the ER
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    Estrogen metabolites.
Nathan Goodyear

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

  • 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.
  • 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.
  • Increased ADA activity in breast cancer patients has also been reported
  • 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 oxidative stress gives rise to inflammation which could further aggravates the disease
  • 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.
  • Experimental and epidemiological evidences implicate the involvement of oxygen derived free radical in the pathogenesis of breast cancer.
  • 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.
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    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

HIF-1-mediated metabolic reprogramming reduces ROS levels and facilitates the metastati... - 0 views

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    HIF-1alpha and ROS relationship in cancer
Nathan Goodyear

Hyperbaric oxygen as an adjunctive therapy in treatment of malignancies, including brai... - 0 views

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    great review of HBOT in cancer therapies
Nathan Goodyear

Antineoplastic Mechanisms of Niclosamide in Acute Myelogenous Leukemia Stem C... - 0 views

  • Here, we report on niclosamide as an antileukemic agent with two independent antineoplastic mechanisms: NF-κB pathway inactivation and ROS generation
  • In this report, we validated the inhibitory action of niclosamide against tumor necrosis factor (TNF)–induced NF-κB activation in AML cells and identified its mechanism, together with generation of reactive oxygen species (ROS), as being responsible for induced apoptosis of AML cells
  • NF-κB plays a critical role in inflammation, antiapoptotic responses, and carcinogenesis
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  • pharmacologic inhibition of NF-κB was effective in killing AML cells
  • High NF-κB expression is found in primitive human AML blast cells
  • niclosamide inhibited the TNF-induced NF-κB reporter activity in a dose- and time-dependent manner
  • niclosamide inhibiting TNF-induced IKK phosphorylation (Fig. 2A), niclosamide may exert its inhibitory effect at the TAK1 step
  • Pretreatment with niclosamide completely blocked the time- and dose-dependent TNFα-induced alteration of the NF-κB–DNA complex
  • niclosamide inhibited constitutively active NF-κB binding to DNA in U266 cells
  • niclosamide completely abolished the TNFα-induced phosphorylation of IKKα/β and IκBα
  • Accordingly, the TNFα-induced degradation of IκBα was abrogated by niclosamide
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    Old anti-parasitic medication, niclosamide, found to have anti-leukemic acitivty through inactivation of NF-kappaB and increase in ROS production in in Vitro and in Vivo study.
Nathan Goodyear

Vitamin C and cancer revisited - 0 views

  • It is well known that vitamin C, or ascorbic acid, is an effective biologic antioxidant and does not act as a pro-oxidant under normal conditions (5) because it does not readily autoxidize, i.e., react with oxygen (O2) to produce reactive oxygen species, such as superoxide radicals (O2•−) or H2O2
  • However, ascorbate readily donates an electron to redox-active transition metal ions, such as cupric (Cu2+) or ferric (Fe3+) ions, reducing them to cuprous (Cu+) and ferrous (Fe2+) ions, respectively
  • Reduced transition metal ions, in contrast to ascorbic acid, readily react with O2, reducing it to superoxide radicals (Reaction 2), which in turn dismutate to form H2O2 and O2
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  • The H2O2 produced this way (Reactions 1–3) seems to be key to ascorbate's antitumor effect because H2O2 causes cancer cells to undergo apoptosis, pyknosis, and necrosis
  • In contrast, normal cells are considerably less vulnerable to H2O2
  • The reason for the increased sensitivity of tumor cells to H2O2 is not clear but may be due to lower antioxidant defenses
  • In fact, a lower capacity to destroy H2O2—e.g., by catalase, peroxiredoxins, and GSH peroxidases—may cause tumor cells to grow and proliferate more rapidly than normal cells in response to low concentrations of H2O2
  • These observations, combined with the inhibitory effect on xenograft growth, provide the proof of concept that millimolar concentrations of extracellular ascorbate, achievable by i.p. injection or i.v. infusion in experimental animals and humans, respectively, exert pro-oxidant, antitumor effects in vivo.
  • They also show that the concentration of the ascorbyl radical correlates with the concentration of H2O2 in interstitial fluid, whereas no H2O2 can be detected in blood or plasma
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    review of the mechanism of how extracellular AA, only obtainable from parenteral dosing, can produce H2O2 extracellularly to then be cytotoxic to cancer cells.
Nathan Goodyear

Vitamin C increases viral mimicry induced by 5-aza-2′-deoxycytidine | PNAS - 0 views

  • Vitamin C alone at concentrations up to 57 μM had little effect on cell growth but was toxic at 228 μM (SI Appendix, Fig. S1B), in line with recent studies of high vitamin C concentrations (125–2,000 μM)
  • In our combination approach, vitamin C increased the effects of low doses of 5-aza-CdR, with 57 μM vitamin C almost doubling the growth inhibition
  • Using the Chou–Talalay method (28), we found that the two compounds indeed acted synergistically, rather than additively, to inhibit cancer cell growth over the physiological ranges of vitamin C in healthy individuals (26–84 μM)
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  • These results show that targeting the cancer DNA methylome by combining low-dose 5-aza-CdR and vitamin C stimulates the expression of ERVs, the induction of a cell-autonomous immune activation response, and increased apoptosis of cancer cells
  • The addition of vitamin C to treatment protocols therefore may be a straightforward way to increase the clinical efficacy of such drugs in MDS and leukemia patients
  • Vitamin C deficiency has been seen previously in patients with multiple types of cancer, including hematological malignancies (35⇓–37). We predict that these patients might receive the most benefits from the combination treatment.
  • induction of an innate immune response
  • We therefore measured plasma concentrations of vitamin C in a small number of patients with miscellaneous hematologic malignancies. Strikingly, 58% of patients with hematological neoplasia who were not taking vitamin C supplements had severe vitamin C deficiency (serum concentration <11.4 μM, at which clinical features of scurvy may be manifested) (34), and 33% had vitamin C levels below the normal range
  • it is possible that vitamin C was oxidized to DHA before it was transported into the cells
  • Oral administration of vitamin C should be sufficient for the therapeutic strategy, because the concentrations reported in this study would not require i.v. administration.
    • Nathan Goodyear
       
      This statement lacks a basic understanding of vitamin C pharmacokinetics.
  • Vitamin C is an essential nutrient for humans and has been reported to increase IFN levels in human cells upon virus infection
  • daily treatment with vitamin C alone at physiological concentrations enhanced the expression of viral-defense genes relative to untreated cells
  • When combined with low-dose 5-aza-CdR, physiological concentrations of vitamin C synergistically inhibited cancer-cell growth and induced apoptosis. Such synergy was associated with increased ERV expression and dsRNA in treated cells. The mechanism of action differs from that of vitamin C at higher doses, which involves its pro-oxidant activity, including GSH inhibition, to generate reactive oxygen species
  • This activity has been shown to induce DNA damage and to enhance the sensitivities of myeloid malignancies, multiple myeloma, and cutaneous T-cell lymphoma to arsenic trioxide (41⇓⇓–44). It also can increase chemosensitivity of ovarian cancer cells (27) and selectively kill KRAS or BRAF mutant colorectal cancer cells by inhibiting GAPDH
  • reactive oxygen species
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    91% of patients with hematologic malignancies have vitamin C levels that are either low or severly deficient. This study found that vitamin C plus low dose DNA methyltransferase inhibitors have synergistic inhibition of cancer cell proliferation and increased apoptosis.  Unfortunately, the authors claimed that oral vitamin C would be sufficient which indicates an incredible lack of understanding of vitamin C pharmacokinetics.
Nathan Goodyear

Frontiers | Management of Glioblastoma Multiforme in a Patient Treated With Ketogenic M... - 0 views

  • The SOC for GBM was modified in this patient to initiate KMT prior to surgical resection, to eliminate steroid medication, and to include HBOT as part of the therapy
  • the greatest therapeutic benefit for patients (near 1.0)
  • The observed reduction in blood glucose in our patient would reduce lactic acid fermentation in the tumor cells, while the elevation of ketone bodies would fuel normal cells thus protecting them from hypoglycemia and oxidative stress
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  • Previous studies showed that GBM survival and tumor growth was correlated with blood glucose levels
  • Evidence indicates that glioma cells cannot effectively use ketone bodies for energy due to defects in the number, structure, and function of their mitochondria
  • The accuracy of the GKI as a predictor for therapeutic efficacy, however, is better when ketone bodies are measured from the blood than when measured from the urine
  • A reduction of glucose-driven lactic acid fermentation would not only increase tumor cell apoptosis, but would also reduce inflammation and edema in the tumor microenvironment thus reducing tumor cell angiogenesis and invasion
  • Besides serving as a metabolic fuel for GBM, glutamine is also an essential metabolite for normal immune cells
  • therapies that inhibit glutamine availability and utilization must be strategically employed to avoid inadvertent impairment of immune cell functions
  • we used the non-toxic green tea extract, EGCG, and chloroquine in an attempt to limit glutamine availability to the tumor cells
  • EGCG is thought to target the glutamate dehydrogenase activity that facilitates glutamine metabolism in GBM cells
  • Chloroquine, on the other hand, will inhibit lysosomal digestion thus restricting fermentable amino acids and carbohydrates from phagocytosed materials in the tumor microenvironment
  • HBOT to increase oxidative stress in the tumor cells
  • As glucose and glutamine fermentation protect tumor cells from oxidative stress, reduced availability of these metabolites under ketosis could enhance the therapeutic action of HBOT, as we recently described
  • Prior to subtotal tumor resection and standard of care (SOC), the patient conducted a 72-h water-only fast
  • Following the fast, the patient initiated a vitamin/mineral-supplemented ketogenic diet (KD) for 21 days that delivered 900 kcal/day
  • KD (increased to 1,500 kcal/day at day 22
  • the patient received metformin (1,000 mg/day), methylfolate (1,000 mg/day), chloroquine phosphate (150 mg/day), epigallocatechin gallate (400 mg/day), and hyperbaric oxygen therapy (HBOT) (60 min/session, 5 sessions/week at 2.5 ATA)
  • Biomarkers showed reduced blood glucose and elevated levels of urinary ketones with evidence of reduced metabolic activity (choline/N-acetylaspartate ratio) and normalized levels of insulin, triglycerides, and vitamin D
  • This is the first report of confirmed GBM treated with a modified SOC together with KMT and HBOT, and other targeted metabolic therapies
  • Glioblastoma multiforme (GBM) is the most common and malignant of the primary adult brain cancers
  • less than 20% of younger adults generally survive beyond 24 months
  • glucose and glutamine are the primary fuels that drive the rapid growth of most tumors including GBM
  • Glucose drives tumor growth through aerobic fermentation (Warburg effect), while glutamine drives tumor growth through glutaminolysis
  • The fermentation waste products of these molecules, i.e., lactic acid and succinic acid, respectively, acidify the tumor microenvironment thus contributing further to tumor progression
  • Glucose and glutamine metabolism is also responsible for the high antioxidant capacity of the tumor cells thus making them resistant to chemo- and radiotherapies
  • The reliance on glucose and glutamine for tumor cell malignancy comes largely from the documented defects in the number, structure, and function of mitochondria and mitochondrial-associated membranes
  • These abnormalities cause the neoplastic GBM cells to rely more heavily on substrate level phosphorylation than on oxidative phosphorylation for energy
  • dexamethasone not only increases blood glucose levels but also increases glutamine levels through its induction of glutamine synthetase activity
    • Nathan Goodyear
       
      use mannitol instead
  • Calorie restriction and restricted KD are anti-angiogenic, anti-inflammatory, anti-invasive, and also kill tumor cells through a proapoptotic mechanism
  • Evidence also shows that therapeutic ketosis can act synergistically with several drugs and procedures to enhance cancer management improving both progression free and overall survival
  • hyperbaric oxygen therapy (HBOT) increases oxidative stress on tumor cells especially when used alongside therapies that reduce blood glucose and raise blood ketones
  • The glutamine dehydrogenase inhibitor, epigallocatechin gallate (EGCG) is also proposed to target glutamine metabolism
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    Case study of Glioblastoma treated with ketogenic metabolic therapy as an adjuct to modified standard therapy.
Nathan Goodyear

Broad targeting of angiogenesis for cancer prevention and therapy - 0 views

  • vascular endothelial growth factor (VEGF), fibroblast growth factor-2 (FGF-2), interleukin-8 (IL-8), placental growth factor (PlGF), transforming growth factor-beta (TGFbeta), platelet derived growth factor (PDGF), angiopoietins (Angs) and others (reviewed in [4])
  • The switch may also involve down-regulation of endogenous inhibitors of angiogenesis such as endostatin, angiostatin or thrombospondin (reviewed in [5]) and has thus been regarded as the result of tipping the net balance between positive and negative regulators
  • There is a complex interrelationship between tumor hypoxia and tumor angiogenesis
  • ...17 more annotations...
  • chronic hypoxia
  • acute hypoxia
  • Environmental stress as a result of low oxygen and proper nutrient deprivation, such as glucose deprivation, are capable of inducing VEGF mRNA stabilization resulting in increased levels of the secreted ligand and angiogenic growth
  • HIFalpha subunits accumulate in the cytoplasm where they bind HIFbeta to form a heterodimer that subsequently translocates to the nucleus to activate transcription of target genes, including genes important for various processes such as metabolism (glucose transporter (GLUT)-1, hexokinase (HK)-1), cell growth (cyclin (CCN)-D1 [23]) and also angiogenesis, such as erythropoietin, VEGF and PDGF [24] (summarized in Fig. 1)
  • When oxygen levels are low (hypoxia; red arrow) PHDs cannot hydroxylate HIFalphas thereby allowing them to escape pVHL-mediated degradation. HIFalpha subunits accumulate and bind to their heterodimeric partner, HIFbeta, translocate into the nucleus and activate a cascade of hypoxic signaling first by the transcription of various target genes including microRNAs that are important for tumor promoting pathways
  • c-Src is also capable of activating HIFs by indirectly inhibiting PHD activity via the NADPH oxidase/Rac pathway.
  • mTOR can also promote stabilization and HIF transcriptional activity
  • hypoxia inducible factors (HIFs), heterodimeric transcription factors composed from alpha and beta subunits, which can be rapidly stabilized to fluidly adapt to and overcome the effects of a hypoxic environment
  • Curcumin inhibits the expression of epidermal growth factor receptor (EGFR), VEGFR-1, VEGFR-2 and VEGFR-3, and the kinase activity of Src and FAK, which are responsible for the induction of angiogenic genes as well as endothelial cell polarity and migration
  • Curcumin also reduces the MMP-2 and MMP-9 expression, along with the suppression of growth and invasion potential of tumor cells in culture and xenograft experiments
  • The expression of angiogenic biomarkers COX-2 and serum levels of VEGF were significantly reduced in the curcumin-treated group
  • Resveratrol inhibits capillary endothelial cell growth and new blood vessel growth in animals
  • interrupting cell proliferation, inducing apoptosis
  • [155] and impeding angiogenesis by suppressing VEGF expression through down-regulation of HIF-1alpha
  • resveratrol was reported to inhibit cell proliferation of human ovarian cancer cells and human osteosarcoma cells by attenuating HIF-1alpha
  • prevents cytokine-induced vascular leakage and tumor metastasis
  • The underlying molecular mechanisms include: blocking VEGF- and FGF-receptor-mediated MAPK activation, inhibiting Akt- and MAPK-driven HIF-1alpha basal expression and its induction by IGF-1, stimulating the proteasomal degradation of HIF-1alpha, inhibiting phosphatidyl inositol (PI)-3K/Akt and Ras/mitogen/extracellular signal-regulated kinase (MEK)/ERK pathways, and activation of forkhead box (FOX)O transcription factors
  •  
    natural compounds to attach cancer explained.
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