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Nathan Goodyear

Effects of short-term high-fat overfeeding on genome-wide DNA methylation in the skelet... - 0 views

  • short-term HFO introduces DNA methylation changes on a genome-wide scale in human skeletal muscle
  • These changes were only partly reversed after 6–8 weeks
  • The induction of DNA methylation changes after 5 days of HFO supports the growing awareness of DNA methylation as a dynamic signal that is possibly relevant to short-term day-to-day metabolic adaptations, including acute exercise
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  • Diverging DNA methylation levels between elderly, but not young, genetically identical twins indicate that environmental exposures throughout life may permanently influence DNA methylation, suggesting some preservation of de novo DNA methylation in adults
  • our finding of a slow reversibility rate indicates the demethylation process may be somewhat impeded compared with the induction of methylation changes by diet, which could have implications for the preservation or build-up of CpG methylation over time
  • A slow reversibility of DNA methylation induced by carcinogenic agents has likewise been observed due to ingestion of high-fat diets in rodents
  • the relationship between DNA methylation and gene expression is not always straightforward
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    Study finds variability of methylation and some genetic expression alteration with high fat diet.  Restated, what you eat interacts with your DNA to alter genetic expression.  This has implications on initiation of therapy as well as response to therapy.
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

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

Ibuprofen alters human testicular physiology to produce a state of compensated hypogona... - 0 views

  • The levels of LH in the ibuprofen group had increased by 23% after 14 d of administration
  • This increase was even more pronounced at 44 d, at 33%
  • We found an 18% decrease (P = 0.056) in the ibuprofen group compared with the placebo group after 14 d (Fig. 1A) and a 23% decrease (P = 0.02) after 44 d (Fig. 1C). Taken together, these in vivo data suggest that ibuprofen induced a state of compensated hypogonadism during the trial, which occurred as early as 14 d and was maintained until the end of the trial at 44 d
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  • We first investigated testosterone production after 24 and 48 h of ibuprofen exposure to assess its effects on Leydig cell steroidogenesis. Inhibition of testosterone levels was significant and dose-dependent (β = −0.405, P = 0.01 at 24 h and β = −0.664, P < 0.0001 at 48 h) (Fig. 2A) and was augmented over time
  • The AMH data show that the hypogonadism affected not only Leydig cells but also Sertoli cells and also occurred as early as 14 d of administration
  • Sertoli cell activity showed that AMH levels decreased significantly with ibuprofen administration, by 9% (P = 0.02) after 14 d (Fig. 1B) and by 7% (P = 0.05) after 44 d compared with the placebo group
  • Examination of the effect of ibuprofen exposure on both the ∆4 and ∆5 steroid pathways (Fig. 2B) showed that it generally inhibited all steroids from pregnenolone down to testosterone and 17β-estradiol; the production of each steroid measured decreased at doses of 10−5–10−4 M. Under control conditions, production of androstenediol and dehydroepiandrosterone (DHEA) was below the limit of detection except in one experiment with DHEA
  • Measuring the mRNA expression of genes involved in steroidogenesis in vitro showed that ibuprofen had a profound inhibitory effect on the expression of these genes (Fig. 3 B–D), consistent with that seen above in our ex vivo organ model. Taken together, these data examining effects on the endocrine cells confirm that ibuprofen-induced changes in the transcriptional machinery were the likely reason for the inhibition of steroidogenesis.
  • Suppression of gene expression concerned the initial conversion of cholesterol to the final testosterone synthesis. Hence, expression of genes involved in cholesterol transport to the Leydig cell mitochondria was impaired
  • A previous study reported androsterone levels decreased by 63% among men receiving 400 mg of ibuprofen every 6 h for 4 wk
  • We next examined the gene expression involved in testicular steroidogenesis ex vivo and found that levels of expression of every gene that we studied except CYP19A1 decreased after exposure for 48 h compared with controls
  • the changes in gene expression indicate that the transcriptional machinery behind the endocrine action of Leydig cells was most likely impaired by ibuprofen exposure.
  • Together, these data show that ibuprofen also directly impairs Sertoli cell function ex vivo by inhibiting transcription
  • ibuprofen use in men led to (i) elevation of LH; (ii) a decreased testosterone/LH ratio and, to a lesser degree, a decreased inhibin B/FSH ratio; and (iii) a reduction in the levels of the Sertoli cell hormone AMH
  • The decrease in the free testosterone/LH ratio resulted primarily from the increased LH levels, revealing that testicular responsiveness to gonadotropins likely declined during the ibuprofen exposure. Our data from the ex vivo experiments support this notion, indicating that the observed elevation in LH resulted from ibuprofen’s direct antiandrogenic action
  • AMH levels were consistently suppressed by ibuprofen both in vivo and ex vivo, indicating that this hormone is uncoupled from gonadotropins in adult men. The ibuprofen suppression of AMH further demonstrated that the analgesic targeted not only the Leydig cells but also the Sertoli cells, a feature encountered not only in the human adult testis but also in the fetal testis
  • ibuprofen displayed broad transcription-repression abilities involving steroidogenesis, peptide hormones, and prostaglandin synthesis
  • a chemical compound, through its effects on the signaling compounds, can result in changes in the testis at gene level, resulting in perturbations at higher physiological levels in the adult human
  • The analgesics acetaminophen/paracetamol and ibuprofen have previously been shown to inhibit the postexercise response in muscles by repressing transcription
  • Previous ex vivo studies on adult testis have indeed pointed to an antiandrogenicity, only on Leydig cells, of phthalates (41), aspirin, indomethacin (42), and bisphenol A (BPA) and its analogs
  • ibuprofen’s effects were not restricted to Leydig and Sertoli cells, as data showed that the expression of genes in peritubular cells was also affected
  • short-term exposure
  • In the clinical setting, compromised Leydig cell function resulting in increased insensitivity to LH is defined as compensated hypogonadism (4), an entity associated with all-cause mortality
  • compensated hypogonadic men present with an increased likelihood of reproductive, cognitive, and physical symptoms
  • an inverse relationship was recently reported between endurance exercise training and male sexual libido
  • AMH concentrations are lower in seminal plasma from patients with azoospermia than from men with normal sperm levels
  • inhibin B is a key clinical marker of reproductive health (32). The function of AMH, also secreted by Sertoli cells, and its regulation through FSH remain unclear in men
  • the striking dual effect of ibuprofen observed here on both Leydig and Sertoli cells makes this NSAID the chemical compound, of all the chemical classes considered, with the broadest endocrine-disturbing properties identified so far in men.
  • after administration of 600 mg of ibuprofen to healthy volunteers
  • 14 d or at the last day of administration at 44 d
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    ibuprofen alters genetic expression that results in decreased Testosterone production.
Nathan Goodyear

Chemotherapy Alters Monocyte Differentiation to Favor Generation of Cancer-Supporting M... - 0 views

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    Chemotherapy induces M2 polarization in the TME
Nathan Goodyear

The Role of Vitamin C in Human Immunity and Its Treatment Potential Against COVID-19: A... - 0 views

  • vitamins A, B, C, E, B6, B12, folate, zinc, iron, copper, and selenium
  • White blood cells, including neutrophils and monocytes, accumulate concentrations of vitamin C up to 100 times greater than that of plasma
  • Vitamin C is a crucial component of both the innate (nonspecific) and adaptive (specific) portions of the immune system
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  • play a role during the initial chemotactic response of neutrophils shortly after infection
  • following vitamin C supplementation, a 20% increase in neutrophil chemotactic activity was observed
  • also contributes to the phagocytosis and killing of microbes by neutrophils
  • low levels of vitamin C occurring in high-stress situations
  • maturation, proliferation, and viability of T cells have all been shown to be upregulated by the presence of normal physiologic concentrations of vitamin C
  • Vitamin C has been shown to directly affect the number of Igs released from B cells
  • vitamin C among healthy young adult males showed a significant increase in serum levels of IgA, IgG, and IgM
  • effects of high-dose vitamin C on cytokine levels in cancer patients, finding decreased amounts of the cytokines Interleukin-1 alpha (IL-1 alpha), IL-2, IL-8, and tumor necrosis factor-alpha (TNF-alpha) after high-dose vitamin C infusion
  • when vitamin C was supplemented with vitamin E in healthy adults, it increased the production of cytokines IL-1 beta and TNF-alpha
  • vitamin C acts to modulate the levels of cytokines to prevent them from fluctuating in either direction
  • vitamin C also acts as an important antioxidant to the cells of the immune system.
  • human leukocytes, neutrophils, in particular, possess the ability to transport the oxidized form of vitamin C across its membrane to use as a defense mechanism against ROS produced during an immune response
  • Vitamin C also can recover other endogenous antioxidants in the body such as vitamin E and glutathione, returning them to their active state
  • vitamin C can decrease the activation of NF-kB
  • can reduce harmful nitrogen-based compounds such as N-nitrosamines and nitrosamides, both of which are carcinogenic 
  • subjects taking oral vitamin C supplementation saw a 60% to 90% reduction in oxidative stress compared to a placebo control
  • subjects infused with vitamin C alone had a 516% increase in glutathione levels compared to subjects not provided the 500 mg daily supplementation
  • hydroxylating proline and lysine
  • mature and stabilize the tissue of a healing wound
  • healing
  • oral surgery
  • improved soft tissue regeneration
  • vitamin C increases the mRNA levels of type I and type III collagen in the human dermis
  • Studies have demonstrated that those with low levels of vitamin C are at a significantly higher risk of respiratory infection compared to those with normal levels
  • viral cold duration was reduced by about 8% in adults and 13.5% in children using prophylactic daily doses of 200 mg of oral vitamin C
  • prophylactically supplementing vitamin C decreases the risk of infection with respiratory viruses such as the common cold
  • combined with probiotics, oral vitamin C supplementation showed a 33% decrease in the incidence of respiratory tract infections in preschool-age children [
  • high-dose oral supplementation of vitamin C managed to prevent or reduce symptoms if taken before or just after the onset of cold- or flu-like symptoms
  • improvements in oxygen saturation and decreased IL-6 levels (a marker of inflammation) in the treatment group compared to the control group
  • 8 g doses of oral vitamin C
  • there is a negative correlation between age and serum levels of vitamin C
  • Patients with COVID-19 will likely also experience depletion in serum levels of vitamin C as a direct result of the upregulation of the immune system to combat the infection
  • Colunga et al. suggested that oral vitamin C can be combined with oral Quercetin, an antiviral flavonoid, to improve Quercetin’s ability to block viral membrane fusion of SARS-CoV-2
  • high doses of 1-2 g/day of oral vitamin C could prevent other upper respiratory infections
  • It appears vitamin C supplementation by itself does not provide a striking benefit in preventing COVID-19 infection for those without a deficiency
    • Nathan Goodyear
       
      Flawed statement. What is normal? Vitamin D. Many variables effect levels and dose, including the two compartment kinetics and absorption.
  • Hiedra et al. were able to show decreases in inflammatory biomarkers, such as D-dimer and ferritin
  • some evidence to support that prophylactic use of vitamin C helps reduce the severity of respiratory infection symptoms once a subject has already been infected
  • oral vitamin C in combination with zinc provided the largest amount of antibody titers 42 days
  • linear relationship between days of vitamin C therapy and survival duration
  • other studies were unable to find any definitive improvement concerning therapy with vitamin C
    • Nathan Goodyear
       
      Either these studies are designed to fail or the authors are lacking some basic understanding of pharmacokinetics and pharmacodynamics with vitamin C.
  • Fowler et al. aimed to see if a high-dose vitamin C infusion would benefit patients affected by ARDS, but they were unable to conclude that vitamin C infusion, compared to a placebo, could decrease vascular inflammation and damage in ARDS
    • Nathan Goodyear
       
      At what dose, duration, frequency???
  • in a sample of 67 COVID-19-positive ICU patients, 82% of them displayed plasma vitamin C levels below 0.4 mg/dL
    • Nathan Goodyear
       
      They are kind of make the point from my earlier note.
  • continuous vitamin C infusion at a rate of 60 mg/kg/day for four days decreased the need for mechanical ventilation and vasopressor use but had no significant effect on overall mortality
    • Nathan Goodyear
       
      Again, designed to fail or ignorance designed the study which failed
  • Carr et al. suggested that high-dose IV vitamin C is most effective when treating sepsis as septic patients receiving the normal daily recommendations through diet still showed decreased vitamin C levels
  • High-dose IV vitamin C treatment has also been shown by Kakodkar et al. to decrease syndecan-1, an endothelial glycocalyx that contributes to mortality in septic patients
  • combined with hydrocortisone and thiamine, septic patients treated with 1.5 g of IV vitamin C every six hours showed a distinct decrease in their SOFA scores and none of the patients treated developed organ failure
  • combined with hydrocortisone and thiamine, septic patients treated with 1.5 g of IV vitamin C every six hours showed a distinct decrease in their SOFA scores and none of the patients treated developed organ failure
  • reduced overall mortality
  • reduced overall mortality
  • propose the use for high-dose vitamin C to aid in the treatment of septic shock-induced hypotension
  • treatment of severe sepsis using a high dose (up to 200 mg/kg/day) of IV vitamin C was explored in phase I, a double-blind, randomized, placebo-controlled trial by Fowler et al. [75]. Their findings included a reduction in SOFA scores and decreased vascular injury compared to a placebo control group, all while showing minimal adverse side effects
    • Nathan Goodyear
       
      High dose here is laughable. Again, duration and frequency also.
  • Maintaining a daily intake of 75 and 100 mg for men and women, respectively, as recommended by the U.S. Institute of Medicine
    • Nathan Goodyear
       
      This recommendation is FRANK IGNORANCE
pharmacybiz

People To Be 'Patient And Courteous' With Pharmacy Teams - 0 views

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    Amid the ongoing furore over shortages of Lateral Flow Device (LFD) test kits that led pharmacy staff to bear customers' wrath, the National Pharmacy Association (NPA) and Company Chemists Association (CCA) have jointly appealed the public to be "patient and courteous to pharmacy teams". In an open letter, the two organisations have urged patients and customers to be patient, courteous and safe while visiting their local pharmacies. Highlighting the efforts put in by healthcare workers to keep everyone safe through this tough winter, the two organisations said the pressure of Covid-19 and shortage of LFD kits have sometimes led to verbal abuse of pharmacy staff. Mark Lyonette, NPA chief executive said: "The vast majority of pharmacy customers and patients are polite and understanding. The supply situation with Lateral Flow Tests is stretching people's patience, but that's no excuse for abusive behaviour and people need to understand the constraints on pharmacy teams at this time." Alongside their routine job of providing medicines, health advice and a range of NHS services, pharmacies have put in extra effort to protect people during the pandemic.
Nathan Goodyear

Ascorbic Acid Chemosensitizes Colorectal Cancer Cells and Synergistically Inhibits Tumo... - 0 views

  • therapeutic potential has been supported by a large and consistent body of evidences from in vitro
  • Ascorbic acid might act as a way to deliver hydrogen peroxide (H2O2) to the tissues
  • pharmacological concentrations of AA were capable of inducing anti-proliferative, cytotoxic and genotoxic effects
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  • chemosensitizing
  • pharmacological concentrations of AA can sensitize cancer cells to chemotherapy, enhancing its antineoplastic effect
  • synergistic effect with conventional chemotherapeutic drugs is a fact already reported, in various types of cancer, by numerous authors, namely in pancreatic (Espey et al., 2011), prostate (Gilloteaux et al., 2014), lung (Lee et al., 2017), breast (Kurbacher et al., 1996; Wu et al., 2017) and ovarian (Ma et al., 2014) cancers.
  • chemosensitizing effect of vitamin C has already been proven by several authors in various types of cancer
  • intravenous pharmacological concentrations, may not only potentiate the effects of conventional chemotherapy, but also improve the quality of life of cancer patients
  • AA reinforced the anti-proliferative activity of 5-FU
  • Combined treatment induced a reduction of 11.5% and 43% in cell viability compared with AA or Iri therapies, respectively, emphasizing the synergistic effect
  • cytotoxic effect occurred with treatment with Iri alone, but also this effect was further potentiated by the presence of AA.
  • association of AA with Oxa showed very promising results, considering that a synergistic effect was demonstrated, in almost all conditions
  • AA and Oxa seem to act synergistically by the activation of the intrinsic pathway of apoptosis, translated on the statistically significant increase of the ratio between BAX and BCL-2 proteins, which in turn is associated with a decrease of Δψm
    • Nathan Goodyear
       
      Apoptosis -> decrease in mitochondrial membrane potential
  • Previous results obtained by our group showed that AA mediates reactive oxygen species (ROS) formation capable of irreparably damaging DNA
  • oxidative role of AA may be a key factor on the synergistic anti-cancer mechanism
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