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Nathan Goodyear

The role of testosterone replacement ther... [Urol Clin North Am. 2007] - PubMed - NCBI - 0 views

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    with holding Testosterone therapy in men after radical prostatectomy for prostate cancer is not supported in the scientific literature.
Nathan Goodyear

Increased extracellular levels of ascorbate in the striatum after middle cerebral arter... - 0 views

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    vitamin C released in the brain with an ischemic stroke.  Question: is this a way to provide scavenger for free radicals following a stroke?
Nathan Goodyear

Controlled trial of N-acetylcysteine for patients with probable Alzheimer's disease - 0 views

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    NAC shown to improve secondary measures of cognitive function in small study in those with Alzheimer's disease. NAC proves to be a reliable means to reduce free radical induced advanced glycation end productions and resultant inflammation. Also was shown to be well tolerated.
Nathan Goodyear

NAD+ and Vitamin B3: From Metabolism to Therapies - 0 views

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    NAD+ is very important in ATP production and as a means to counter free radicals.  This is a nice discussion of NAD metabolism.  
Nathan Goodyear

The molecular basis of neurodegeneration in multiple sclerosis - 0 views

  • Inflammation is the most predominant feature during the early (relaping) phases of the disease and declines with aging of the patients and disease duration
  • in the process of oligodendrocyte destruction and demyelination in MS lesions iron is liberated from its intracellular ferritin bound stores into the extracellular space, where it is taken up by microglia and macrophages and again stored together with ferritin. When this happens in MS lesions in an environment, where free radicals are produced by oxidative burst, iron can be liberated from ferritin and transformed into reactive Fe++[114], which reacts with hydrogen peroxide to generate highly reactive hydroxyl radicals [36] and thus amplifies oxidative damage and associated cellular injury
  • anti-inflammatory or immunomodulatory treatments are effective in the relapsing stage, but the benefit is lost when the patients have entered the progressive phase
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  • Inflammation will remain a key target, since the data suggest that microglia activation and oxidative burst is driven by inflammation throughout all stages of the disease.
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    Very nice review of the neurodegenerative process in MS.  
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

Dietary curcumin counteracts the outcome of traum... [Exp Neurol. 2006] - PubMed - NCBI - 0 views

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    curcumin functions to reduce inflammation and free radicals.  Curcumin also increases BDNF post TBI, which will improve synaptic plasticity, cognition, and memory.  
Nathan Goodyear

Oxidative Stress and the Aging Brain: From Theory to Prevention - Brain Aging - NCBI Bo... - 0 views

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    Must read on the free radical theory of aging to application of disease prevention as it relates to neurodegenerative disease
Nathan Goodyear

Multiple Myeloma Tumor Cells are Selectively Killed by Pharmacologically-dosed Ascorbic... - 0 views

  • Recent reports indicate that a certain ROS concentration is required for high-dose vitamin C to induce cytotoxicity in cancer cells.
  • The generation of ascorbyl- and H2O2 radicals by PAA increases ROS stress in cancer cells
  • In this study, we report that PAA is efficacious in killing MM cells in vitro and in vivo models, which generated levels of 20–40 mM ascorbate and 500 nM ascorbyl radicals after intraperitoneal administration of 4 g ascorbate per kilogram of body weight (Chen et al., 2008Chen et al., 2008), in xenograft MM mice
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  • These data suggest that PAA may show a therapeutic advantage to blood cancers vs solid tumors because of the communication between tumor cells and blood plasma
  • These results strongly suggest that the mechanism of PAA killing of MM cells is indeed iron-dependent
  • These results suggest that PAA administration in SMM may be able to prevent progression to symtomatic MM
  • A recent study by Yun and colleagues demonstrated that vitamin C selectively kills KRAS and BRAF mutant colorectal cancer cells by targeting GAPDH, but spares normal cells
  • RAS family genes show the most frequent mutations in MM. KRAS, NRAS and BRAF are mutated in 22%, 20% and 7% of MM samples
  • the disease stage rather than the mutation of RAS and/or BRAF is the major predictive factor for PAA sensitivity in MM treatment
  • Other molecular mechanisms including ATP depletion and ATM-AMPK signaling have been reported to explain PAA-induced cell death
  • our pilot study also suggested that PAA could overcome drug resistance to bortezomib in MM cells
  • Our findings complement reported studies and further address the mechanism of action using clinical samples in which we observed that PAA killed tumor cells with high iron content, suggesting that iron might be the initiator of PAA cytotoxicity
  • combination of PAA with standard therapeutic drugs, such as melphalan, may significantly reduce the dose of melphalan needed
  • Combined treatment of reduced dose melphalan with PAA achieved a significantly longer progression-free survival than the same dose of melphalan alone.
  • These data also suggest that the bone marrow suppression induced by high-dose melphalan can be ameliorated by the combination of PAA with lower dose of melphalan because of the lack of toxicity of PAA on normal cells with low iron content.
  • if creatinine clearance is <30 mL/min, high dose ascorbic acid should be not administrated.
  • In MM preclinical and clinical studies, ascorbate was used as an adjunct drug and showed controversial results (Harvey et al., 2009, Perrone et al., 2009, Held et al., 2013, Sharma et al., 2012, Nakano et al., 2011, Takahashi, 2010, Sharma et al., 2009, Qazilbash et al., 2008). However, none of these tests used pharmacological doses of ascorbate and intravenous administration
  • Multiple myeloma (MM) is a plasma cell neoplasm.
  • Cameron and Pauling reported that high doses of vitamin C increased survival of patients with cancer
  • pharmacologically dosed ascorbic acid (PAA) 50–100 g (Chen et al., 2008, Padayatty et al., 2004, Hoffer et al., 2008, Padayatty et al., 2006, Welsh et al., 2013), administered intravenously, has potent anti-cancer activity and its role as anti-cancer therapy is being studied at the University of Iowa and in other centers
  • In the presence of catalytic metal ions like iron, PAA administered intravenously exerts pro-oxidant effects leading to the formation of highly reactive oxygen species (ROS), resulting in cell death
  • the labile iron pool (LIP) is significantly elevated in MM cells
  • The survival of CD138+ cells in vitro was significantly decreased following PAA treatment in all 9 MM
  • In contrast, no significant change of cell viability was observed in CD138− BM cells from the same patients
  • The same effect of PAA was also observed in the SMM patients
  • no response to PAA was detected in CD138+ cells from the 2 MGUS patients
  • the combination of melphalan plus PAA showed greater tumor burden reduction than each drug alone, suggesting a synergistic activity between these two drugs
  • Both catalase and NAC protect cells from oxidative damage
  • cells pretreated with NAC and catalase became resistant to PAA even at high doses
  • adding deferoxamine (DFO), an iron chelator, to OCI-MY5 cells before PAA treatment was also sufficient to prevent PAA-induced cellular death
  • iron is essential for PAA to achieve its anti-cancer activity
  • PAA induced early necrosis (Fig. 3Fig. 3A, 60 min) followed by late apoptosis
  • results further indicated that PAA induced mitochondria-mediated apoptosis
  • PAA by reacting with LIP and generating ROS induces mitochondria-mediated apoptosis in which AIF1 cleavage is important for cell death.
  • ROS and H2O2 are well known factors mediating PAA-induced cancer cell death
  • PAA was sensitive to all 9 MMs and 2 SMMs
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    animal study finds high-dose, pharmacologic vitamin C found to kill multiple myeloma cells via pro-oxidant effect found in similar studies in dealing with different cancers.
Nathan Goodyear

Hyperthermia and Chemotherapy - Holland-Frei Cancer Medicine - NCBI Bookshelf - 0 views

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    Brief review from book on severe hyperthermia and chemotherapy: The mechanisms that underlie the synergy may include (1) increased cellular uptake of drug, (2) increased oxygen radical production, and (3) increased DNA damage and inhibition of repair; potential use of HT with many drugs is its ability to reverse, at least partially, drug resistance
Nathan Goodyear

Phase I safety trial of intravenous ascorbic acid in patients with severe sepsis - 1 views

  • Padayatty and colleagues showed that high-level ascorbic acid plasma concentrations could only be achieved by intravenous administration
  • No patient in the low or high dose ascorbic acid treatment arms of this study suffered any identifiable adverse event
  • a pharmacologic ascorbic acid treatment strategy in critically ill patients with severe sepsis appears to be safe
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  • subnormal plasma ascorbic acid levels are a predictable feature in patients with severe sepsis
  • Ascorbic acid depletion in sepsis results from ascorbic acid consumption by the reduction of plasma free iron, ascorbic acid consumption by the scavenging of aqueous free radicals (peroxyl radicals), and by the destruction of the oxidized form of ascorbic acid dehydroascorbic acid
  • Sepsis further inhibits intracellular reduction of dehydroascorbic acid, producing acute intracellular ascorbic acid depletion
  • Ascorbic acid treated patients in this study exhibited rapid and sustained increases in plasma ascorbic acid levels using an intermittent every six hours administration protocol
  • Septic ascorbic acid-deficient neutrophils fail to undergo normal apoptosis. Rather, they undergo necrosis thereby releasing hydrolytic enzymes in tissue beds, thus contributing to organ injury
  • We speculate that intravenous ascorbic acid acts to restore neutrophil ascorbic acid levels
  • Repletion of ascorbic acid in this way allows for normal apoptosis, thus, preventing the release of organ damaging hydrolytic enzymes.
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    Study finds IV vitamin C in patients with sepsis is very safe and blunts the effects (endothelial damage, end organ damage...) of sepsis.  Of note, the IV vitamin C group reached serum levels of ascorbic acid of 1,592 to 5,722 micromol/L.  The IV groups maintained elevated serum C levels for up to 96 hours post infusion.  
fitspresso

LeanBiome™ (Official) | Get Save UpTo $540 Today Only! - 0 views

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    LeanBiome™ (Official) | Get Save UpTo $540 Today Only! usleanbiome.com LeanBiome™ Hurry Up! Offer Expires in: 00 HOUR 29 MINUTE 59 SECOND LeanBiome Attention! Get Special 84% Discount Today Faster fat burning and weight loss Healthy cholesterol and sugar levels Higher energy levels Regular price: $129 Only for: 39$ What Is LeanBiome? LeanBiome Lean for Good is a weight loss dietary supplement derived from scientifically researched ingredients and comprehensively developed to help people achieve sustainable weight control. The formula comes in a capsule format that is easy to take and is made with natural ingredients from plants and other sources to achieve its goals. The main ingredient in LeanBiome is piperine, which has been found to affect the body's ability to absorb micronutrients and other compounds more effectively. LeanBiome is a dietary supplement that claims to help weight management. It contains 100% natural ingredients that support healthy weight loss. It does not interfere with any natural process making it safe for use. It ranks among the top weight loss supplements that claim to provide a permanent solution. LeanBiome is made by a company named Lean for Good. It is made with natural and research-backed ingredients that help you lose excess fat without hassles. It is sold in capsule form. The company assures the composition is GMO, gluten, and soy-free. As for manufacturing standards, you need not fret. The company makes the supplement in a facility certified by the FDA. How Does LeanBiome Work? The starting period of the LeanBiome program includes a detoxification process that effectively removes any accumulated ree radicals, toxins, fand oxidative stress. This cleansing enables improved blood circulation, setting the stage for the body to initiate its own fat-burning mechanisms. To enhance metabolic activity, introducing the lean bacteria contained in LeanBiome to your gut microbiome is a beneficial approach. This activation triggers r
Nathan Goodyear

Acute prooxidant effects of vitamin C in... [Free Radic Biol Med. 2005] - PubMed - NCBI - 0 views

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    This study found a pro oxidant effect of the addition of 5 grams of IV vitamin C with EDTA chelation.  As dosing of IV vitamin C goes, 5 grams is quite small.  Vitamin C has been shown to have varying effects (pro oxidant versus antioxidant) dictated by the dosage.  One wonders if higher dosing IV vitamin C provides antioxidant effects?
Nathan Goodyear

Uptake, recycling, and antioxidant actio... [Free Radic Biol Med. 2002] - PubMed - NCBI - 0 views

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    Alpha lipoic acid is shown to protect the vascular endothelium against oxidative damage.
Nathan Goodyear

Roundup Disrupted Male Reproductive Func... [Free Radic Biol Med. 2013] - PubMed - NCBI - 0 views

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    Glyphosate, component of Roundup is well known to be an endocrine disruptor.  This rat study describes the mechanism  of disruption of the Sertoli cells resulting in male infertility.  In addition to the disruption of spermatogenesis, Glyphosate was shown to deplete glutathione levels compromising detoxification.  If that is not enough, oxidative damage marker TBARS was elevated.  
Nathan Goodyear

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

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    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

N-acetylcysteine (NAC) in neurological disorders: mechanisms of action and therapeutic ... - 0 views

  • There is a marked increase in expression of TNF in active multiple sclerosis (MS)
  • a correlation exists between cerebrospinal fluid levels of TNF and the severity and progression of disease
  • With cytokine activation, free-radical production increases and this has been demonstrated in MS
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  • NAC inhibits the toxicity of TNF and in an animal model of MS
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    Good discussion of NAC and neurodegenerative diseases.
Nathan Goodyear

ScienceDirect.com - Free Radical Biology and Medicine - Anti-inflammatory effects of be... - 1 views

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    Benfotiamine's anti-inflammatory effect is through the inhibition of LOX-5 and COX-2.
Nathan Goodyear

TJEM : Vol. 224 (2011) , No. 3 pp.209-213 - 0 views

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    L-carnitine shown to increase antioxidant levels of catalase, SOD, and glutathione perioxidase
Nathan Goodyear

BMC Neuroscience | Full text | In Vitro Assessment of Tobacco Smoke Toxicity at the BBB... - 0 views

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    Vitamin C and Vitamin E shown to protect against the many pro-oxidant effects of smoking
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