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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

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

  • 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
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  • 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
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    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

Clinical experience with intravenous administration of ascorbic acid: achievable levels... - 0 views

  • Patients with higher tumor markers are likely to have higher tumor burden, higher oxidative stress and, therefore, are more likely to have lower post IVC plasma levels.
  • Our data also showed that cancer patients with metastasis tend to have lower post-IVC vitamin C levels than those without metastasis
  • Lower peak plasma concentrations are obtained in cancer patients than in healthy subjects. Cancer patients who are deficient in vitamin C prior to therapy tend to achieve lower plasma levels post infusion.
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  • Patients with higher inflammation or tumor burdens, as measured by CRP levels or tumor antigen levels, tend to show lower peak plasma ascorbate levels after IVC.
  • Patients with metastatic tumors tend to achieve lower post infusion plasma ascorbate levels than those with localized tumors.
  • Meta-analyses of clinical studies involving cancer and vitamins also conclude that antioxidant supplementation does not interfere with the efficacy of chemotherapeutic regiments
  • Most of the prostate cancer patients studied, 75±19% (95% confidence), showed reductions in PSA levels during the course of their IVC therapy
  • Laboratory studies suggest that, at high concentrations, ascorbate does not interfere with chemotherapy or irradiation and may enhance efficacy in some situations
  • Cameron and Pauling observed fourfold survival times in terminal cancer patients treated with intravenous ascorbate infusions followed by oral supplementation
  • The inflammatory microenvironment of cancer cells leads to increasing oxidative stress, which apparently depletes vitamin C, resulting in lower plasma ascorbate concentrations in blood samples post IVC infusion. Another explanation for this finding may be that cancers are themselves more metabolically active in their uptake of vitamin C, causing subjects to absorb more of the vitamin, and as a results show lower plasma ascorbate concentrations in blood post IVC infusion.
  • patients with severely elevated CRP levels attain plasma ascorbate concentrations after IVC infusions that are only 65% of those attained for subjects with normal CRP levels
  • The finding of decreased plasma ascorbate levels in cancer patients may relate to the molecular structure of ascorbic acid; in particular, the similarity of its oxidized form, dihydroascorbic acid, to glucose
  • Since tumor have increased requirement for glucose [67], transport of dehydroascorbate into the cancer cells via glucose transport molecules and ascorbate through sodium-dependent transporter may be elevated
  • Increased accumulation of ascorbic acid in the tumor site was supported by measurements of the level of ascorbic acid in tumors in animal experiments
  • patients with advanced malignancies may have lower level of ascorbic acid in tissue, creating a higher demand for the vitamin C
  • IVC therapy appears to reduce CRP levels in cancer patients.
  • CRP concentrations directly correlate with disease activity in many cases and can contribute to disease progression through a range of pro-inflammatory properties.
  • Being an exquisitely sensitive marker of systemic inflammation and tissue damage, CRP is very useful in screening for organic disease and monitoring treatment responses
  • ncreases in CRP concentrations have been associated with poorer prognosis of survival in cancer patients, particularly with advance disease independent of tumor stage
  • Regarding inflammation, 73±13% of subjects (95% confidence) showed a reduction in CRP levels during therapy. This was an even more dramatic 86±13% (95% confidence) in subjects who started therapy with CRP levels above 10 mg/L
  • patients treated by IVC with follow-up several year showed that suppression of inflammation in cancer patients by high-dose IVC is feasible and potentially beneficial
  • Inflammation is a marker of high cancer risk, and poor treatment outcome
  • The subjects with highly elevated CRP concentrations have a three-fold elevation “all-cause” mortality risk and a twenty-eight fold increase in cancer mortality risk
  • cancer patients may need higher doses to achieve a given plasma concentration.
  • patients with lower vitamin C levels may see more distribution of intravenously administered ascorbate into tissues and thus attain less in plasma.
  • When treating patients with IVC, the first treatment likely serves to replenish depleted tissue stores, if those subjects were vitamin C deficient at the beginning of the treatment. Then, in subsequent treatments, with increasing doses, higher plasma concentrations can be attained. On-going treatments serve to progressively reduce oxidative stress in cancer patients.
  • large doses given intravenously may result in maximum plasma concentrations of roughly 30 mM, a level that has been shown to be sufficient for preferential cytotoxicity against cancer cells
  • oral intake of vitamin C exceeded 200 mg administered once daily, it was difficult to increase plasma and tissue concentrations above roughly 200 μM.
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    Great review on the use of IV vitamin C in cancer and to reduce inflammation.  The article does a great job of discussing the mechanism of vitamin C therapy in cancer as well as the proposed reasons for low vitamin C in cancer patients.  The study also highlights the obstacles to rise in vitamin C levels post IV vitamin C in cancer patients.
Nathan Goodyear

How is the Immune System Suppressed by Cancer - 1 views

  • 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
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  • 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
       
      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
       
      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
       
      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
       
      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
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    Great review of the immunosuppression in cancer driven by the likes of NO.
Nathan Goodyear

Interleukin‐2 enhances the natural killer cell response to Herceptin‐coated H... - 1 views

  • administration of low‐dose IL‐2 results in expansion of a CD3– / CD56+ NK cell population in patients with advanced cancer
  • approximately 20 % will overexpress theHer2 / neu proto‐oncogene
  • In breast cancer, Her2 / neu overexpression is associated with a worse histologicalgrade, decreased relapse‐free and overall survival periods, and altered sensitivity to chemotherapeutic regimens
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  • NK cells are large granular lymphocytes that comprise approximately 10 % of circulating lymphocytes
  • all human NK cells express the CD56 antigen
  • treatment with various concentrations of IL‐2 in vivo may induce distinct functions within the NK cell compartment and, therefore, may have profound effects on NK cell‐mediated cytotoxicity
  • CD56bright
  • CD56dim
  • We show here that ADCC conducted by NK cells in vitro is enhanced by IL‐2 activation and is critically dependent on interactions between FcγRIII on NK cells and Herceptin‐coated tumor targets
  • administration of low‐dose IL‐2 to patients results in the marked expansion of a CD56+ population of immune effectors with the ability to lyse antibody‐coated cancer targets
  • NK cells represented only 7 % of lymphocytes prior to therapy but comprised over 50 % of the population after 10 weeks of low‐dose IL‐2
  • These data suggest that the enhanced ADCC seen following the expansion of NK cells with low‐dose IL‐2 is likely due to an increase in the overall number of NK cells
  • co‐administration of IL‐2 with rhu4D5 mAb will enhance activation of NK cell effector functions
  • Stimulation of NK cells with IL‐2 resulted in a significant increase in the lysis of rhu4D5‐coated targets
  • We have shown that costimulation with IL‐2 plus rhu4D5 results in significant production of IFN‐γ by NK cells with concomitant up‐regulation of cell‐surface activation and adhesion molecules
  • It has been previously demonstrated that continuous low‐dose IL‐2 can expand a CD56+ lymphocyte population, and we have now shown that this cell population is a potent mediator of ADCC against rhu4D5 mAb‐coated Her2 / neu+ targets
  • These results suggest that administration of low‐dose IL‐2 can be used to expand NK cell numbers, while higher doses may be used to enhance their cytolytic capacity in the setting of mAb therapy
  • we have demonstrated that NK cell lysis of Her2 / neu+ breast cancer cell lines in the presence of rhu4D5 mAb is markedly enhanced following stimulation with IL‐2
  • we have presented evidence that administration of low‐dose IL‐2 in vivo results in the expansion of a potent NK cell effector population
  • Our experiments suggest that NK cells costimulated with IL‐2 and immobilized IgG can secrete potent immunomodulatory cytokines which may serve to potentiate the anti‐tumor immune response.
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    low dose IL-2 found to expand NK levels in conjuction in with herceptin in HER-2 positive breast cancer cell lines.
Nathan Goodyear

Clinical predictors of mortality due to COVID-19 based on an analysis of data of 150 pa... - 0 views

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    To be read
Nathan Goodyear

Intravenously administered vitamin C as cancer therapy: three cases - 0 views

  • peak plasma concentrations obtained intravenously are estimated to reach 14 000 μmol/L, and concentrations above 2000 μmol/L may persist for several hours
  • Emerging in vitro data show that extracellular ascorbic acid selectively kills some cancer but no normal cells by generating hydrogen peroxide
  • Death is mediated exclusively by extracellular ascorbate, at pharmacologic concentrations that can be achieved only by intravenous administration
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  • Vitamin C may serve as a pro-drug for hydrogen peroxide delivery to extravascular tissues, but without the presence of hydrogen peroxide in blood
  • not all cancer cells were killed by ascorbic acid in vitro
  • Intravascular hemolysis was reported after massive vitamin C administration in people with glucose-6-phosphate dehydrogenase deficiency
  • Administration of high-dose vitamin C to patients with systemic iron overload may increase iron absorption and represents a contraindication
  • Ascorbic acid is metabolized to oxalate, and 2 cases of acute oxalate nephropathy were reported in patients with pre-existing renal insufficiency given massive intravenous doses of vitamin C
  • Rare cases of acute tumour hemorrhage and necrosis were reported in patients with advanced cancer within a few days of starting high-dose intravenous vitamin C therapy, although this was not independently verified by pathologic review
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    IV vitamin C associated with prolonged survival in 3 patients with different cancers.  Peak serum levels reached 14,000 micromol/L, which levels above the 1,000 micro mol/L (cancer cell cytotoxic threshold) were maintained for hours
Nathan Goodyear

The Risk of Fluoroquinolone-induced Tendinopathy and Tendon Rupture - 0 views

  • Achilles tendinitis or rupture is among the most serious side effects associated with FQ use
  • The large body of data provided by clinical reports, histopathological examination, and experimental studies provides cogent evidence supporting a direct link between FQ use and tendonitis/tendon rupture
  • Risk factors associated with FQ-induced tendon disorders include age greater than 60 years, corticosteroid therapy, renal failure, diabetes mellitus, and a history of musculoskeletal disorders
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  • The average age of FQ-induced tendinopathy is 64 years, with a male-to-female ratio of 2:1, and a 27-percent incidence of bilateral involvement
  • Although more than 95 percent of cases of tendinitis/rupture secondary to FQ involve the Achilles tendon, other reported sites of tendon involvement include the quadriceps, peroneus brevis, and rotator cuff
  • FQs demonstrate a 3.8-fold greater risk for development of Achilles tendinitis/rupture
  • a large population-based case control analysis, patients treated with FQs exhibited a substantially increased risk of developing tendon disorders overall (1.7-fold), tendon rupture (1.3-fold), and ATR (4.1-fold)
  • patients taking FQs with concurrent exposure to corticosteroids were found to experience a compounding effect on the risk of tendon rupture, specifically a 46-fold greater predisposition
  • Some authors have recommended that patients with a history of Achilles tendinitis and advanced age should not be prescribed FQ antibiotics
  • Approximately 50 percent of patients will recover within 30 days, with 25 percent of patients having symptoms persistent for longer than two months
  • The mean latency period between the start of FQ treatment and occurrence of tendinopathy has been reported to be a few hours to months, with a median onset of 6 days
  • The exact pathophysiology of FQ-induced tendinopathy remains elusive
  • it is possible that FQs have a direct cytotoxic effect on enzymes found in mammalian musculoskeletal tissue
  • It has been theorized that FQs disproportionately affect human tendons that have a limited capacity for repair, such as in older patients or structural compromise (i.e., pre-existing tendinopathy or trauma)
  • histopathological findings are similar to those observed in overuse conditions in athletes
  • Treatment with a FQ should be discontinued and physical therapy initiated
  • treatment should include rest and decreasing the physical load on the tendon.
  • Approximately 85 percent of patients present in less than one month
  • Because rupture can occur even late in the course of treatment or after discontinuation of FQ use, patients receiving a FQ should be counseled to seek medical attention immediately if symptoms, such as redness, pain, swelling, and stiffness, develop
  • FQs should be used cautiously in patients with risk factors associated with tendinitis, such as advanced age, history of tendon rupture, corticosteroid use, and/or acute or chronic renal dysfunction
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    Great review of the link between flouroquinolones and Tendinitis and Tendon rupture.  Yes, there is a direct link.
Nathan Goodyear

Acute Exercise Remodels Promoter Methylation in Human Skeletal Muscle: Cell Metabolism - 0 views

  • our results provide evidence to suggest that acute exercise induces gene-specific DNA hypomethylation in human skeletal muscle
  • Our results suggest that DNA methylation is a component of the exercise-induced effect on expression of these genes.
  • Caffeine exposure decreased promoter methylation of Pgc-1α, Tfam, Mef2a, Cs, and Pdk4
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  • the effect of exercise on DNA methylation in human skeletal muscle and provide evidence that acute exercise alters promoter methylation of exercise-responsive genes in a dose-dependent manner
  • DNA methylation was unaltered 48 hr after a 3-week exercise training program, whereas RNA expression of PGC-1α and TFAM promoters was elevated (data not shown), further suggesting that DNA hypomethylation is a transient mechanism involved in mRNA synthesis
  • Our findings that ionomycin, AICAR, or ROS production increased mRNA expression without altering promoter methylation may support the notion that DNA methylation does not exclusively control exercise-induced gene expression
  • acute exercise leads to transient changes in DNA methylation in adult skeletal muscle
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    Small study finds acute exercise is associated with epigenetic alteration of muscle through methylation.  This study found a hypomethylation of the genes PGC-1alpha, PDK4, and PPAR-delta with a respondent increase in expression.  The methylation activity was in the promoter region of these genes.
Nathan Goodyear

Chronic exposure to Low dose bacterial lipopolysaccharide inhibits leptin signaling in ... - 0 views

  • Obesity and models of obesity induced by ingestion of HF-diet in rodents are associated with chronically elevated circulating levels of LPS
  • chronic low-dose administration of LPS induces leptin-resistance in vagal afferent neurons and abolition of CCK-induced inhibition of food intake
  • HF fat feeding has been shown to enhance gastrointestinal permeability promoting the translocation of LPS to the circulation
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  • LPS leads to an increase in SOCS3 expression [20]. SOCS3 is a negative regulator of leptin signaling
  • We observed a significant increase in energy intake in the LPS-treated rats
  • the data provides a mechanism linking changes in gut microbiota induced by ingestion of HF diets to dysregulation of food intake and body weight
  • SOCS3 is an important mechanism by which leptin resistance develops in vagal afferent neurons and coincides with the onset of hyperphagia
  • Chronic low-dose LPS treatment induced TLR4 activation and MyD88 signaling in vagal afferent neurons, associated with increased SOCS3 expression and reduced leptin-signaling, characterized by the absence of leptin-induced pSTAT3.
  • We demonstrate that this chronic low dose LPS is sufficient to induce leptin–resistance in vagal afferent neurons, reduced sensitivity to the satiating effects of CCK, and loss of vagal afferent plasticity
  • it suggests that the increase in food intake and body weight we observed at week 6 in the LPS treated rats may be caused by LPS-induced leptin resistance.
  • chronic LPS treatment of mice for four weeks increased body weight
  • chronic LPS treatment of mice for four weeks increased subcutaneous fat
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    Very interesting study.  High fat diet in rats induced gut flora change that resulted in LPS which induced appetite through leptin resistance and reduced cholecystokinin signaling.
Nathan Goodyear

Oncotarget | NADH autofluorescence, a new metabolic biomarker for cancer stem cells: Id... - 0 views

  • Vitamin C was ~10 times more potent than 2-DG for the targeting of CSCs
  • Cancer stem-like cells (CSCs) are thought to be the root cause of chemotherapy-resistance and radio-resistance
  • ultimately leading to treatment failure in patients with advanced disease [1-3]. They have been directly implicated mechanistically in tumor recurrence and metastasis, resulting in poor patient survival
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  • mitochondrial biogenesis may be a key driver of the CSC phenotype
  • Our results indicate that increased mitochondrial oxidative stress and high NADH levels are both key characteristics of the CSC metabolic phenotype
  • high levels of NAD(P)H auto-fluorescence are known to be a surrogate marker for mitochondrial “power”, high OXPHOS capacity and increased ATP production
  • CSCs may be strictly dependent on NAD(P)H to maintain their enhanced mitochondrial function
  • an intact NAD+ salvage pathway is strictly required for mammosphere formation, supporting our results using NAD(P)H auto-fluorescence, which enriched CSC activity by more than 5-fold.
  • Since glycolysis is especially critical for maintaining the TCA cycle, OXPHOS and overall mitochondrial function, we next assessed the effects of known glycolytic inhibitors
  • we show that two other natural products that function as effective glycolysis inhibitors, also inhibited mammosphere formation. More specifically, vitamin C (ascorbic acid), which induces oxidative stress and inhibits the activity of GAPDH (a key glycolytic enzyme) [17], also inhibited mammosphere formation, with an IC-50 of 1 mM (Figure 7B). Therefore, vitamin C was ~10 times more potent than 2-DG at targeting CSC propagation
  • silibinin (the major active constituent of silymarin, an extract of milk thistle seeds) [18], which specifically functions as an inhibitor of glucose uptake, blocked mammosphere formation, with an IC-50 between 200 and 400 µM
  • caffeic acid phenyl ester (CAPE), a key component of honey-bee propolis, has potent anti-cancer properties
  • Propolis has a strong history of medicinal use, dating back more than 2,000 years
  • Because of it aromatic ring structure (Figure 8), we speculated that CAPE might function as a potent inhibitor of oxidative mitochondrial metabolism
  • CAPE quantitatively inhibits the mitochondrial oxygen consumption rate (OCR) and, in turn, induces the onset of aerobic glycolysis (ECAR)
  • CAPE shows a clear selectivity for targeting CSCs and adherent cancer cells, relative to normal fibroblasts.
  • CAPE functions as a “natural” mitochondrial OXPHOS inhibitor, that preferentially targets the CSC sub-population. This could explain CAPE’s known anti-cancer properties
  • Our data directly shows that a small fraction of the total cell population, characterized by increased PGC1α activity, high mitochondrial ROS/H2O2 and high NADH levels, has the ability to survive and grow under anchorage-independent conditions, driving mammosphere formation
  • We highlight the utility of certain natural products, such as Silibinin, Vitamin C and CAPE, that could be used to therapeutically target CSCs. Silibinin is the major active component of silymarin, which is an extract prepared from milk thistle seeds.
  • high NADH is a property that is conserved between normal and cancerous stem cells
  • Previous studies have also shown that when non-CSCs and CSCs are both fed mitochondrial fuels (such as L-lactate or ketone bodies), that CSCs quantitatively produce more NADH in response to this stimulus
  • CSCs may be strictly dependent on NADH to maintain their enhanced mitochondrial function
  • The Noble Prize winner, Linus Pauling, was among the first to describe and clinically test the efficacy of Vitamin C, as a relatively non-toxic anti-cancer agent
  • Vitamin C has two mechanisms of action. First, it is a potent pro-oxidant, that actively depletes the reduced glutathione pool, leading to cellular oxidative stress and apoptosis in cancer cells. Moreover, it also behaves as an inhibitor of glycolysis, by targeting the activity of GAPDH, a key glycolytic enzyme.
  • Here, we show that Vitamin C can also be used to target the CSC population, as it is an inhibitor of energy metabolism that feeds into the mitochondrial TCA cycle and OXPHOS
  • Vitamin C may prove to be promising agent for new clinical trials, aimed at testing its ability to reduce CSC activity in cancer patients, as an add-on to more conventional therapies, to prevent tumor recurrence, further disease progression and metastasis
  • Interestingly, a breast cancer based clinical study has already shown that the use of Vitamin C, concurrent with or within 6 months of chemotherapy, significantly reduces both tumor recurrence and patient mortality
  • CAPE quantitatively reduces mitochondrial oxygen consumption (OCR), while inducing a reactive increase in glycolysis (ECAR). As such, it potently inhibits mammosphere formation with an IC-50 of ~2.5 µM. Similarly, it also significantly inhibits cell migration
  • we also demonstrate that 7 different inhibitors of key energetic pathways can be used to effectively block CSC propagation, including three natural products (silibinin, ascorbic acid and CAPE). Future studies will be necessary to test their potential for clinical benefit in cancer patients.
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    The future of cancer therapy is cancer stem cells.  Study finds that Vitamin C, silymarin, and bee propolis blocks mitochondrial energy pathways in cancer stem cells.  Vitamin C is a known glycolytic inhbitor. Vitamin C was found to inhibit glycolysis via GAPDH targeting to inhibit the energy pathways of the mitochondria in CSCs.  The authors propse that Vitamin C can be used as add on therapies for conventional therapies to specifically attack the CSCs and their contribution to recrurence, treatment resistance, and metastasis potential all in addition to the ability of vitamin C to reduce the side effects of chemotherapy.
Nathan Goodyear

Low-dose Interleukin-2 in the Treatment of Autoimmune Disease | touchONCOLOGY - 0 views

  • affect approximately 5 to 8 % of the US population
  • the incidence and prevalence of autoimmune diseases are rising
  • Type 1 diabetes (T1D), rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and inflammatory bowel disease (IBD) account for the majority of the patients with autoimmune diseases
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  • Autoimmune diseases are characterized by a breakdown of mechanisms that allow the immune system to distinguish between self and nonself and maintain immunologic self-tolerance
  • Tregs, which are important in the maintenance of peripheral immune tolerance.
  • Several subtypes of Tregs exist, the most well studied being CD4+ cells that express high-level CD25 and the transcription factor forkhead box P3 (FOXP3)
  • Treg deficiency or dysfunction is associated with autoimmune disease
  • In clinical studies, decreased levels of circulating CD25+CD4+ T cells have been reported in patients with autoimmune disease
  • These data have led to the hypothesis that augmentation of Tregs may be a useful therapeutic strategy in autoimmune disease
  • Treg augmentation has resulted in clinical improvements in numerous animal models of autoimmune diseases
  • the administration of in vitro expanded CD4+CD25highCD127-Tregs has been found to be safe and may help to preserve β-cell function in children with T1D
  • ability of IL-2 to augment the numbers and function of CD4+ Tregs.
  •  
    Great article.  Immune dysfunction plays role in autoimmune disease and cancer.  Treg cells sit at the center of autoimmunity.  This artice highlights the different uses: low dose IL2 therapy to augment Tregs and reduce autoinflammation and high dose IL2 to augment Treg cells in the fight against cancer.
Nathan Goodyear

(PDF) Determination of the anti-glioblastoma effect of artesunate and its potential tar... - 0 views

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    Interesting study here with positive effects in the treatment of glioblastoma with Artesunate. Interesting, the cytotoxic effects were countered by the administration of NAC.
KELLY147

Retail Sales Tips : 8 Tips to Boost Sales in Retail Stores - 1 views

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    Since many people are engaged in promoting their brands on social media platforms, they forget that they can achieve business success through visual merchandising.
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