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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
  • ...20 more annotations...
  • 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

Implications of free radicals and antioxidant levels in carcinoma of the breast: A neve... - 0 views

www.indianjcancer.com/article.asp

SOD superoxide disumutase catalase antioxidants antioxidant breast cancer cancer malondialdehyde MDA lipid peroxides oxidative stress inflammation

shared by Nathan Goodyear on 10 Nov 14 - No Cached
  • Experimental investigations as well as clinical and epidemiological findings have provided evidence supporting the role of reactive oxygen metabolites or free radicals such as singlet oxygen O 2 - , superoxide anions (O 2 ), hydrogen peroxide (H­2 O2 ) and hydroxyl radical in the etiology of cancer.
  • Certain aldehydes such as Malonyldialdehyde (MDA), the end product of lipid peroxidation arising from free radical degeneration of polyunsaturated fatty acids can cause cross linking in lipids, proteins and nucleic acids leading to cellular damage.
  • In this study, patients with cancer exhibited higher levels of MDA, both in tissues and serum (p<0.001) compared to the control group [Table 1]. In tissue, the MDA level in stage IV was significantly higher as compared to stage I indicating increased free radical activity with increasing severity of cancer
  • ...6 more annotations...
  • From these observations, it can be concluded that MDA levels play an important role in assessing the outcome of cancer
  • SOD and CAT are considered primary antioxidant enzymes, since they are involved in direct elimination of reactive oxygen metabolites. [13-16] They also act as anti-carcinogens and inhibitors at initiation and promotion/transformation stage in carcinogenesis
  • In our study, SOD and CAT levels were found to be low in all cancer patients as compared to controls
  • Fridovich and Tayarani have demonstrated in their respective studies that the reduction in SOD activity increases the toxic effects of O2 - and this might lead to severe cellular damage.
  • Mehrotra et al. in their study also observed high levels of MDA and low levels of SOD and CAT in patients of cancer cervix which is in sync with our observations.
  • strong evidence regarding the definitive role of free radicals in breast malignancy.
  • Nathan Goodyear on 10 Nov 14
     
    This study finds a strong correlation between advancing breast cancer, decreased catalase and SOD with increasing MDA.  The authors of this study conclude this is a key factor in carcinogenesis and not a by-product of cancer.  This flies in the face of traditional medicines fear of antioxidant therapy in cancer.
Nathan Goodyear

Investigations on oxidativ... [Eur Arch Psychiatry Clin Neurosci. 1999] - PubMed - NCBI - 0 views

www.ncbi.nlm.nih.gov/...10654103

AGE advanced glycation end products neurodegenerative disease free radicals Alzheimer's Parkinson's disease antioxidants inflammation

shared by Nathan Goodyear on 13 Jun 12 - No Cached
  • Nathan Goodyear on 13 Jun 12
     
    This study finds that AGE, advanced glycation end products, play a significant role in free radical generation and neurodegenerative disease. Quote: "... pharmacologoical approaches which break the vicious cycle of oxidative stress and neurodegeneration offer new opportunities for the treatment of AD. These approaches include AGE- inhibitors, antioxidants, and anti-inflammatory substances which prevent radical production." They focus on the pharmacological, how about the natural first?
Nathan Goodyear

The Free Radical Theory of Aging Matures - 0 views

physrev.physiology.org/...547.full

radical free aging mitochondria disease

shared by Nathan Goodyear on 03 Mar 11 - No Cached
  • The Free Radical Theory of Aging Matures
  • Nathan Goodyear on 03 Mar 11
     
    Great discussion on the free-radical theory of aging and the effects of mitochondria
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
  • ...20 more annotations...
  • 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

Pharmacologic ascorbic acid concentrations selectively kill cancer cells: Action as a p... - 0 views

www.pnas.org/...13604.full

IV vitamin C cancer ascorbic acid vitamin C H2O2 GPX glutathione Perioxidase

shared by Nathan Goodyear on 09 Feb 11 - Cached
  • Taken together, these data indicate that ascorbate at concentrations achieved only by i.v. administration may be a pro-drug for formation of H2O2, and that blood can be a delivery system of the pro-drug to tissues.
  • These findings give plausibility to i.v. ascorbic acid in cancer treatment, and have unexpected implications for treatment of infections where H2O2 may be beneficial
  • pharmacologic concentrations of ascorbate killed cancer but not normal cells, that cell death was dependent only on extracellular but not intracellular ascorbate, and that killing was dependent on extracellular hydrogen peroxide (H2O2) formation with ascorbate radical as an intermediate
  • ...48 more annotations...
  • Our data show that ascorbic acid selectively killed cancer but not normal cells, using concentrations that could only be achieved by i.v. administration
  • Ascorbate-mediated cell death was due to protein-dependent extracellular H2O2 generation, via ascorbate radical formation from ascorbate as the electron donor. Like glucose, when ascorbate is infused i.v., the resulting pharmacologic concentrations should distribute rapidly in the extracellular water space (42). We showed that such pharmacologic ascorbate concentrations in media, as a surrogate for extracellular fluid, generated ascorbate radical and H2O2. In contrast, the same pharmacologic ascorbate concentrations in whole blood generated little detectable ascorbate radical and no detectable H2O2. These findings can be accounted for by efficient and redundant H2O2 catabolic pathways in whole blood (e.g., catalase and glutathione peroxidase) relative to those in media or extracellular fluid
  • ascorbic acid administered i.v. in pharmacologic concentrations may serve as a pro-drug for H2O2 delivery to the extracellular milieu
  • H2O2 generated in blood is normally removed by catalase and glutathione peroxidase within red blood cells, with internal glutathione providing reducing equivalents
  • The electron source for glutathione is NADPH from the pentose shunt, via glucose-6-phosphate dehydrogenase. If activity of this enzyme is diminished, the predicted outcome is impaired H2O2 removal causing intravascular hemolysis, the observed clinical finding.
    • Nathan Goodyear
      Nathan Goodyear on 05 Mar 18
       
      The mechansism here is inadequate recycling of GSH due to lack of G6PD, build up of intracellular H2O2 and RBC lysis--hemolysis.
  • Only recently has it been understood that the discordant clinical findings can be explained by previously unrecognized fundamental pharmacokinetics properties of ascorbate
  • Intracellular transport of ascorbate is tightly controlled in relation to extracellular concentration
  • Intravenous ascorbate infusion is expected to drastically change extracellular but not intracellular concentrations
  • For i.v. ascorbate to be clinically useful in killing cancer cells, pharmacologic but not physiologic extracellular concentrations should be effective, independent of intracellular ascorbate concentrations.
    • Nathan Goodyear
      Nathan Goodyear on 05 Mar 18
       
      accumulation of extracellular vitamin C is the effect.
  • It is unknown why ascorbate, via H2O2, killed some cancer cells but not normal cells.
  • There was no correlation with ascorbate-induced cell death and glutathione, catalase activity, or glutathione peroxidase activity.
  • H2O2, as the product of pharmacologic ascorbate concentrations, has potential therapeutic uses in addition to cancer treatment, especially in infections
  • Neutrophils generate H2O2 from superoxide,
  • i.v. ascorbate is effective in some viral infections
  • H2O2 is toxic to hepatitis C
  • Use of ascorbate as an H2O2-delivery system against sensitive pathogens, viral or bacterial, has substantial clinical implications that deserve rapid exploration.
  • Recent pharmacokinetics studies in men and women show that 10 g of ascorbate given i.v. is expected to produce plasma concentrations of nearly 6 mM, which are >25-fold higher than those concentrations from the same oral dose
  • As much as a 70-fold difference in plasma concentrations is expected between oral and i.v. administration,
  • Complementary and alternative medicine practitioners worldwide currently use ascorbate i.v. in some patients, in part because there is no apparent harm
  • Human Burkitt's lymphoma cells
  • We first investigated whether ascorbate in pharmacologic concentrations selectively affected the survival of cancer cells by studying nine cancer cell lines
  • Clinical pharmacokinetics analyses show that pharmacologic concentrations of plasma ascorbate, from 0.3 to 15 mM, are achievable only from i.v. administration
  • plasma ascorbate concentrations from maximum possible oral doses cannot exceed 0.22 mM because of limited intestinal absorption
  • For five of the nine cancer cell lines, ascorbate concentrations causing a 50% decrease in cell survival (EC50 values) were less than 5 mM, a concentration easily achievable from i.v. infusion
  • All tested normal cells were insensitive to 20 mM ascorbate.
    • Nathan Goodyear
      Nathan Goodyear on 05 Mar 18
       
      meaning safe.
  • Lymphoma cells were selected because of their sensitivity to ascorbate
  • As ascorbate concentration increased, the pattern of death changed from apoptosis to pyknosis/necrosis, a pattern suggestive of H2O2-mediated cell death
  • Apoptosis occurred by 6 h after exposure, and cell death by pyknosis was ≈90% at 14 h after exposure
    • Nathan Goodyear
      Nathan Goodyear on 05 Mar 18
       
      work continued beyond the IVC therapy itself
  • In contrast to lymphoma cells, there was little or no killing of normal lymphocytes and monocytes by ascorbate
  • Ascorbate is transported into cells as such by sodium-dependent transporters, whereas dehydroascorbic acid is transported into cells by glucose transporters and then immediately reduced internally to ascorbate
  • Whether or not intracellular ascorbate was preloaded, extracellular ascorbate induced the same amount and type of death.
  • extracellular ascorbate in pharmacologic concentrations mediates death of lymphoma cells by apoptosis and pyknosis/necrosis, independently of intracellular ascorbate.
  • H2O2 as the effector species mediating pharmacologic ascorbate-induced cell death
  • Superoxide dismutase was not protective
  • Because these data implicated H2O2 in cell killing, we added H2O2 to lymphoma cells and studied death patterns using nuclear staining (19, 28). The death patterns found with exogenous H2O2 exposure were similar to those found with ascorbate
  • For both ascorbate and H2O2, death changed from apoptosis to pyknosis/necrosis as concentrations increased
  • Sensitivity to direct exposure to H2O2 was greater in lymphoma cells compared with normal lymphocytes and normal monocytes
  • There was no association between the EC50 for ascorbate-mediated cell death and intracellular glutathione concentrations, catalase activity, or glutathione peroxidase activity
  • H2O2 generation was dependent on time, ascorbate concentration, and the presence of trace amounts of serum in media
  • ascorbate radical is a surrogate marker for H2O2 formation.
  • whatever H2O2 is generated should be removed by glutathione peroxidase and catalase within red blood cells, because H2O2 is membrane permeable
  • The data are consistent with the hypothesis that ascorbate in pharmacologic concentrations is a pro-drug for H2O2 generation in the extracellular milieu but not in blood.
  • The occurrence of one predicted complication, oxalate kidney stones, is controversial
  • In patients with glucose-6-phosphate dehydrogenase deficiency, i.v. ascorbate is contraindicated because it causes intravascular hemolysis
  • ascorbate at pharmacologic concentrations in blood is a pro-drug for H2O2 delivery to tissues.
  • ascorbate, an electron-donor in such reactions, ironically initiates pro-oxidant chemistry and H2O2 formation
  • data here showed that ascorbate initiated H2O2 formation extracellularly, but H2O2 targets could be either intracellular or extracellular, because H2O2 is membrane permeant
    • Nathan Goodyear
      Nathan Goodyear on 05 Mar 18
       
      the conversion of ascorbate to H2O2 occurs extracellular
  • More than 100 patients have been described, presumably without glucose-6-phosphate dehydrogenase deficiency, who received 10 g or more of i.v. ascorbate with no reported adverse effects other than tumor lysis
  • Nathan Goodyear on 09 Feb 11
     
    IV vitamin C benefits cancer patients
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

A radical approach to stroke therapy - 0 views

www.ncbi.nlm.nih.gov/...PMC58670

vitamin C stroke CVA ascorbic acid brain CNS free radicals antioxidants antioxidant therapy

shared by Nathan Goodyear on 08 Mar 12 - No Cached
  • Nathan Goodyear on 08 Mar 12
     
    vitamin C shown to benefit stroke patients.  Vitamin C, ascorbic acid, is extremely prevalent in the brain.  Functions to scavenge free radicals
Nathan Goodyear

Free radicals and aging. [Trends Neurosci. 2004] - PubMed result - 0 views

www.ncbi.nlm.nih.gov/...15374670

free radicals aging

shared by Nathan Goodyear on 08 Feb 11 - No Cached
  • Nathan Goodyear on 08 Feb 11
     
    How free radicals lead to aging
Nathan Goodyear

Ascorbic acid: Chemistry, biology and the treatment of cancer - 0 views

www.ncbi.nlm.nih.gov/...PMC3608474

Fenton reaction ferritin vitamin C Fe cancer

shared by Nathan Goodyear on 07 Jul 19 - No Cached
  • iron and ascorbate has long been used as an oxidizing system; the combination of these two reagents is referred to as the Udenfriend system
  • ascorbate serves as a reducing cofactor for many enzymes
  • uptake of ascorbate from the intestinal tract is very tightly controlled
  • ...11 more annotations...
  • pharmacokinetic data indicate that intravenous administration of ascorbate can bypass this tight control resulting in highly elevated plasma levels
  • ascorbate readily oxidizes to produce H2O2, pharmacological ascorbate has been proposed as a prodrug for the delivery of H2O2 to tumors
  • Ascorbate is an excellent reducing agent and readily undergoes two consecutive, one-electron oxidations to form ascorbate radical (Asc•−) and dehydroascorbic acid (DHA)
  • Ascorbate oxidizes readily. The rate of oxidation is dependent on pH and is accelerated by catalytic metals
  • In near-neutral buffers with contaminating metals, the oxidation and subsequent loss of ascorbate can be very rapid
  • Ascorbate is required for maintaining iron in the ferrous state
  • In the presence of catalytic metal ions, ascorbate can also exert pro-oxidant effects
  • Ascorbate is an excellent one-electron reducing agent that can reduce ferric (Fe3+) to ferrous (Fe2+) iron, while being oxidized to ascorbate radical
  • In a classic Fenton reaction, Fe2+ reacts with H2O2 to generate Fe3+ and the very oxidizing hydroxyl radical
  • e presence of ascorbate can allow the recycling of Fe3+ back to Fe2+, which in turn will catalyze the formation of highly reactive oxidants from H2O2
  • Depending on concentrations, the effects of ascorbate on models of lipid peroxidation can be pro- or antioxidant
  • Nathan Goodyear on 07 Jul 19
     
    ferritin released enhanced pharmacologic ascorbate induced-cytotoxicity, indicating that ferritin with high iron-saturation could be a source of catalytic iron. Consistent with this, ascorbate has also been shown to be capable of releasing iron from cellular ferritin
Nathan Goodyear

How is the Immune System Suppressed by Cancer - 1 views

www.cancertutor.com/ancer-suppresses-immune-system

iNOS cancer immune system

shared by Nathan Goodyear on 23 May 18 - No Cached
  • nitric oxide (NO) released by tumor cells
  • Excellent work by Prof de Groot of Essen, indicated by adding exogenous xanthine oxidase ( XO) in hepatoma cells, hydrogen peroxide was produced to destroy the hepatoma cells
  • NO from eNOS in cancer cells can travel through membranes and over long distances in the body
  • ...43 more annotations...
  • NO also is co linked to VEGF which in turn increases the antiapoptotic gene bcl-2
  • The other important influence of NO is in its inhibition of the proapoptoic caspases cascade. This in turn protects the cells from intracellular preprogrammed death.
  • nitric oxide in immune suppression in relation to oxygen radicals is its inhibitory effect on the binding of leukocytes (PMN) at the endothelial surface
  • Inhibition of inducible Nitric Oxide Synthase (iNOS)
  • NO from the tumor cells actually suppresses the iNOS, and in addition it reduces oxygen radicals to stop the formation of peroxynitrite in these cells. But NO is not the only inhibitor of iNOS in cancer.
  • Spermine and spermidine, from the rate limiting enzyme for DNA synthases, ODC, also inhibit iNOS
  • tolerance in the immune system that decreases the immune response to antigens on the tumors
  • Freund’s adjuvant
  • increase in kinases in these cells which phosphorylate serine, and tyrosine
  • responsible for activation of many growth factors and enzymes
  • phosphorylated amino acids suppress iNOS activity
  • Hexokinase II
  • Prostaglandin E2, released from tumor cells is also an inhibitor of iNOS, as well as suppressing the immune system
  • Th-1 subset of T-cells. These cells are responsible for anti-viral and anti-cancer activities, via their cytokine production including Interleukin-2, (IL-2), and Interleukin-12 which stimulates T-killer cell replication and further activation and release of tumor fighting cytokines.
    • Nathan Goodyear
      Nathan Goodyear on 23 May 18
       
      Th1 cells stimulate NK and other tumor fighting macrophages via IL-2 and IL-12; In contrast, Th2, which is stimulated in allergies and parasitic infections, produce IL-4 and IL-10.  IL-4 and IL-10 inhibit TH-1 activation and the histamine released from mast cell degranulation upregulates T suppressor cells to further immune suppression.
  • Th-2 subset of lymphocytes, on the other hand are activated in allergies and parasitic infections to release Interleukin-4 and Interleukin-10
  • These have respectively inhibitory effects on iNOS and lymphocyte Th-1 activation
  • Mast cells contain histamine which when released increases the T suppressor cells, to lower the immune system and also acts directly on many tumor Histamine receptors to stimulate tumor growth
  • Tumor cells release IL-10, and this is thought to be one of the important areas of Th-1 suppression in cancer patients
  • IL-10 is also increased in cancer causing viral diseases such as HIV, HBV, HCV, and EBV
  • IL-10 is also a central regulator of cyclooxygenase-2 expression and prostaglandin production in tumor cells stimulating their angiogenesis and NO production
  • nitric oxide in tumor cells even prevents the activation of caspases responsible for apoptosis
    • Nathan Goodyear
      Nathan Goodyear on 23 May 18
       
      NO produced by cancer cells inhibits proapoptotic pathways such as the caspases.
  • early stages of carcinogenesis, which we call tumor promotion, one needs a strong immune system, and fewer oxygen radicals to prevent mutations but still enough to destroy the tumor cells should they develop
  • later stages of cancer development, the oxygen radicals are decreased around the tumors and in the tumor cells themselves, and the entire cancer fighting Th-1 cell replication and movement are suppressed. The results are a decrease in direct toxicity and apoptosis, which is prevented by NO, a suppression of the macrophage and leukocyte toxicity and finally, a suppression of the T-cell induced tumor toxicity
  • cGMP is increased by NO
  • NO in cancer is its ability to increase platelet-tumor cell aggregates, which enhances metastases
  • the greater the malignancies and the greater the metastatic potential of these tumors
  • The greater the NO production in many types of tumors,
  • gynecological
  • elevated lactic acid which neutralizes the toxicity and activity of Lymphocyte immune response and mobility
  • The lactic acid is also feeding fungi around tumors and that leads to elevated histamine which increases T-suppressor cells.  Histamine alone stimulates many tumor cells.
    • Nathan Goodyear
      Nathan Goodyear on 23 May 18
       
      The warburg effect in cancer cells results in the increase in local lactic acid production which suppresses lymphocyte activity and toxicity as well as stimulates histamine production with further stimulates tumor cell growth.
  • T-regulatory cells (formerly,T suppressor cells) down regulate the activity of Natural killer cells
  • last but not least, the Lactic acid from tumor cells and acidic diets shifts the lymphocyte activity to reduce its efficacy against cancer cells and pathogens in addition to altering the bacteria of the intestinal tract.
  • intestinal tract bacteria in cancer cells release sterols that suppress the immune system and down regulate anticancer activity from lymphocytes.
  • In addition to the lactic acid, adenosine is also released from tumors. Through IL-10, adenosine and other molecules secreted by regulatory T cells, the CD8+ cells can be inactivated to an anergic state
  • Adenosine up regulates the PD1 receptor in T-1 Lymphocytes and inhibits their activity
  • Adenosine is a purine nucleoside found within the interstitial fluid of solid tumors at concentrations that are able to inhibit cell-mediated immune responses to tumor cells
  • Adenosine appears to up-regulate the PD1 receptor in T-1 Lymphocytes and inhibits the immune system further
  • Mast cells with their release of histamine lower the immune system and also stimulate tumor growth and activate the metalloproteinases involved in angiogenesis and metastases
  • COX 2 inhibitors or all trans-retinoic acid
  • Cimetidine, an antihistamine has been actually shown to increase in apoptosis in MDSC via a separate mechanism than the antihistamine effect
    • Nathan Goodyear
      Nathan Goodyear on 23 May 18
       
      cimetidine is an H2 blocker
  • interleukin-8 (IL-8), a chemokine related to invasion and angiogenesis
  • In vitro analyses revealed a striking induction of IL-8 expression in CAFs and LFs by tumor necrosis factor-alpha (TNF-alpha)
  • these data raise the possibility that the majority of CAFs in CLM originate from resident LFs. TNF-alpha-induced up-regulation of IL-8 via nuclear factor-kappaB in CAFs is an inflammatory pathway, potentially permissive for cancer invasion that may represent a novel therapeutic target
  • Nathan Goodyear on 23 May 18
     
    Great review of the immunosuppression in cancer driven by the likes of NO.
Nathan Goodyear

Vitamin C Improves Endothelium-Dependent Vasodilation by Restoring Nitric Oxide Activit... - 0 views

circ.ahajournals.org/...2222.long

vitamin C hypertension eNOS IV vitamin C NO nitric oxide

shared by Nathan Goodyear on 18 Dec 17 - No Cached
  • Nathan Goodyear on 18 Dec 17
     
    IV Vitamin C improves endothelial vasodilation in essential hypertension.  The Vitamin C reduces the oxygen free radicals which allowed eNOS to increase NO production.  Two take homes: oxygen free radicals may be responsible for the endothelial dysfunction that leads to essential hypertension and vitamin C, particularly IV, can be used to counter this process.  Other studies have shown IV vitamin C to be anti-hypertensive in its action.
Nathan Goodyear

Does insulin dysfunction play a role in... [Trends Pharmacol Sci. 2002] - PubMed - NCBI - 0 views

www.ncbi.nlm.nih.gov/...12084635

insulin insulin resistance Beta-amyloid protein tau proteins Alzheimer' brain neurologys disease AD free radicals

shared by Nathan Goodyear on 11 Jun 12 - No Cached
  • Nathan Goodyear on 11 Jun 12
     
    elevated insulin levels associated with disordered Beta-amyloid metabolism and hyperphosphorylation of tau proteins.  Free radicals also play a role as well.
Nathan Goodyear

Association of Preoperative Testosterone Levels with Biochemical Failure in Men Undergo... - 0 views

online.liebertpub.com/...jomh.2013.0016

testosterone low T prostate cancer men male hormone hormones

shared by Nathan Goodyear on 08 Apr 14 - No Cached
  • Nathan Goodyear on 08 Apr 14
     
    Study finds that low Testosterone preoperative is associated with increased positive surgical margins and worse staging post radical prostatectomy.  Also association with a non-statistical increase in biochemical failure.
Nathan Goodyear

(-)-Epigallocatechin gallate, a polyphenolic tea a... [Experientia. 1996] - PubMed result - 0 views

www.ncbi.nlm.nih.gov/...8841522

Green tea extract EGCG free radical perioxynitrite

shared by Nathan Goodyear on 15 Feb 11 - No Cached
  • Nathan Goodyear on 15 Feb 11
     
    Green tea extract, EGCG, inhibits free-radical damage
Nathan Goodyear

Testosterone Replacement Therapy Following Radical Prostatectomy - The Journal of Sexua... - 0 views

www.jsm.jsexmed.org/...fulltext

Testosterone low T low Testosterone testosterone therapy prostate cancer cancer prostate PSA

shared by Nathan Goodyear on 10 Oct 16 - No Cached
  • Nathan Goodyear on 10 Oct 16
     
    larger study post radical prostatectomy for prostate cancer finds that no increase in PSA with Testosterone therapy in men with non-detectable PSA levels.  F/u was 13 months.
Nathan Goodyear

Testosterone Replacement Therapy in Patients with Prostate Cancer After Radical Prostat... - 0 views

www.ncbi.nlm.nih.gov/...PMC4544840

Testosterone low T low Testosterone Testosterone therapy prostate cancer PSA biochemical recurrence male hormones hormones cancer prostate

shared by Nathan Goodyear on 10 Oct 16 - No Cached
  • Nathan Goodyear on 10 Oct 16
     
    One of the largest studies to date on Testosterone therapy in men post radical prostatectomy for prostate cancer.  This study supports the use of Testosterone therapy in this men with close f/u. A higher biochemical recurrence rate was found in the control group versus the treatment group, though there were 4 with biochemical recurrences in the treatment group.
Nathan Goodyear

Vitamin C and cancer revisited - 0 views

www.ncbi.nlm.nih.gov/...PMC2516245

IV vitamin C cancer vitamin C H2O2 hydrogen peroxide Fe

shared by Nathan Goodyear on 05 Mar 18 - No Cached
  • 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
  • ...6 more annotations...
  • 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
  • Nathan Goodyear on 05 Mar 18
     
    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

Greater Lifetime Pesticide Use Causes Telomere Shortening - 0 views

www.greenmedinfo.com/...e-causes-telomere-shortening-0

pesticide toxins toxicants pesticides Telomere

shared by Nathan Goodyear on 02 Jul 13 - No Cached
  • Nathan Goodyear on 02 Jul 13
     
    Hard to show causation here, but volume of environmental toxicants associated with shortening of Telomeres.  Mechanism?  Increased free radical induced mitochondrial disruption resulting in relocation of the Telomerase enzyme from the mitochondria to the nuclei.   This has been shown to occur in cancer pathogenesis.
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