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Nathan Goodyear

PPARs, Obesity, and Inflammation - 0 views

www.ncbi.nlm.nih.gov/...PMC1783744

obesity inflammation PPARs perioxisome proliferator-activated receptor

shared by Nathan Goodyear on 16 Jan 12 - No Cached
  • increase of 61% within 10 years
  • Many of the inflammatory markers found in plasma of obese individuals appear to originate from adipose tissue
  • obesity is a state of chronic low-grade inflammation that is initiated by morphological changes in the adipose tissue.
  • ...19 more annotations...
  • secretion of MCP-1, resistin, and other proinflammatory cytokines is increased by obesity, the adipose secretion of the anti-inflammatory protein adiponectin is decreased
  • the peroxisome proliferators- activated receptor (PPAR) family are involved in the regulation of inflammation and energy homestasis
  • natural agonists, including unsaturated fatty acids and eicosanoids
  • PPARα also regulates inflammatory processes, mainly by inhibiting inflammatory gene expression
  • upregulation of COX-2 is seen in alcoholic steatohepatitis and nonalcoholic steatohepatitis and has been directly linked to the progression of steatosis to steatohepatitis, the inhibitory effect of PPARα on COX-2 may reduce steatohepatitis
  • PPARα agonists have a clear anorexic effect resulting in decreased food intake, evidence is accumulating that PPARα may also directly influence adipose tissue function, including its inflammatory status.
  • PPARα may govern adipose tissue inflammation in three different ways: (1) by decreasing adipocyte hypertrophy, which is known to be connected with a higher inflammatory status of the tissue [3, 11, 59], (2) by direct regulation of inflammatory gene expression via locally expressed PPARα, or (3) by systemic events likely originating from liver
  • PPARγ is considered the master regulator of adipogenesis
  • Unsaturated fatty acids and several eicosanoids serve as endogenous agonists of PPARγ
  • PPARγ2, which is adipose-tissue specific
  • two different molecular mechanisms have been proposed by which anti-inflammatory actions of PPARγ are effectuated: (1) via interference with proinflammatory transcription factors including STAT, NF-κB, and AP-1
  • and (2) by preventing removal of corepressor complexes from gene promoter regions resulting in suppression of inflammatory gene transcription
  • diet-induced obesity is associated with increased inflammatory gene expression in adipose tissue via adipocyte hypertrophy and macrophage infiltration
  • PPARγ is able to reverse macrophage infiltration, and subsequently reduces inflammatory gene expression
  • Inflammatory adipokines mainly originate from macrophages which are part of the stromal vascular fraction of adipose tissue [18, 19], and accordingly, the downregulation of inflammatory adipokines in WAT by PPARγ probably occurs via effects on macrophages
  • By interfering with NF-κB signaling pathways, PPARγ is known to decrease inflammation in activated macrophages
  • Recent data suggest that activation of PPARγ in fatty liver may protect against inflammation
  • PPARs may influence the inflammatory response either by direct transcriptional downregulation of proinflammatory genes
  • anti-inflammatory properties of PPARs in human obesity
  • Nathan Goodyear on 16 Jan 12
     
    PPARs play pivotal in obesity.  PPARs appear to reduce the inflammatory cascade associated with obesity.  Downregulation of PPARs are associated with increased inflammation.  Natural PPARs include unsaturated fats and eicosanoids.
Nathan Goodyear

Effect of resistance exercise on muscle steroidogenesis | Journal of Applied Physiology - 0 views

jap.physiology.org/...1754

resistance resistance training training exercise Testosterone male female hormone hormones muscle

shared by Nathan Goodyear on 03 Sep 14 - No Cached
  • skeletal muscle cell cultures incubated with DHEA produced testosterone in a DHEA dose-dependent manner
  • Muscle joins a growing list of tissues found to be capable of steroidogenesis
  • testosterone appears to have a role in the maintenance of muscle mass in women, although the importance of this role has not yet been fully established.
  • ...7 more annotations...
  • Circulating testosterone concentrations are generally elevated following a bout of resistance exercise in men (24, 31, 46, 52), whereas findings for the effect of resistance exercise on circulating testosterone in women are equivocal, with increases (10, 42) and no changes observed (22, 31)
  • swimming (51) and treadmill running (2) can significantly increase muscle testosterone concentrations in male and female rats
  • This upregulation of muscle testosterone in rats appears, at least in part, to be due to an increase in 3β-HSD and 17β-HSD type 1 expression
  • The primary finding in this study was that muscle steroidogenesis (i.e., testosterone production) in highly resistance-trained humans was not affected by an acute bout of heavy resistance exercise
  • A secondary finding was that the apparent molecular mass of 17β-HSD type 3 was increased following a single bout of heavy resistance exercise.
  • No differences were found for muscle testosterone or steroidogenic enzyme (17β-HSD type 3 and 3β-HSD types 1 and 2) concentrations between sexes or in response to resistance exercise
  • In conclusion, heavy resistance exercise did not induce changes in muscle steroidogenesis as measured by muscle concentrations of testosterone, 3β-HSD types 1 and 2, and 17β-HSD type 3 in highly resistance-trained young men and women.
  • Nathan Goodyear on 03 Sep 14
     
    Resistance exercise did not increase muscle concentrations of Testosterone in men or women.  The individuals in this study were actively training.  These were not sedentary individuals.
Nathan Goodyear

Toll-like receptor signaling links dietary fatty acids to the metabolic syndrome - 0 views

www.ncbi.nlm.nih.gov/...PMC3099529

TLR toll-like receptors toll-like receptors fatty acids fat metabolic syndrome obesity overweight inflammation dietary

shared by Nathan Goodyear on 08 Oct 12 - No Cached
  • Activation of the innate immune system controls macronutrient metabolism
  • the innate immune response is the first line of defense against invading pathogens, wherein highly conserved pathogen-associated molecular patterns (PAMPs) are recognized by cognate pattern recognition receptors (PRRs
  • many studies have supported the idea that cytokine signaling directly promotes insulin resistance
  • ...10 more annotations...
  • innate immune system may be causally linked to obesity
  • adipose tissue contains a substantial population of macrophages, and macrophage-driven adipose inflammation contributes significantly to the pathogenesis of obesity
  • Collectively, activation of the innate immune system is strongly associated with ASCVD, insulin resistance, and obesity, and recent evidence suggests that much of this association can be traced to a unique family of PRRs known as TLRs
  • TLRs are a family of type I transmembrane receptors, currently thought to comprise at least 13 members in mammals, that specifically recognize a variety of microbial PAMPs and trigger host cellular responses
  • Free SFAs have indeed been demonstrated to elicit TLR4-dependent and TLR2-dependent responses in several cell types.
  • Endogenous SFAs released from adipocytes activate cocultured macrophages via TLR4 [18], indicating the potential for cellular crosstalk in adipose tissue. Collectively, there is a growing body of evidence that SFAs promote, whereas long chain PUFA antagonize, TLR4-dependent and TLR2-dependent signaling in multiple cell models
  • In an elegant study, Shi et al. [16] demonstrated that SFAs activate TLR4-dependent signaling in both macrophages and adipocytes, and mice lacking TLR4 are protected against insulin resistance driven by intravenous lipid infusion
  • In addition to effects in macrophages and adipocytes, SFAs can activate TLR4 in the hypothalamus, which triggers a central inflammatory response that results in resistance to anorexigenic signals
  • endogenous SFAs can indeed promote innate immunity and inflammatory disease
  • This finding strongly supports the work of Hwang and coworkers [19–22] demonstrating that ω-3 PUFAs can effectively counteract SFA-induced TLR4 activation in cultured macrophages and dendritic cells.
  • Nathan Goodyear on 08 Oct 12
     
    high dietary fatty acids linked to metabolic syndrome through TLR.
Nathan Goodyear

Role of Oxidative Stress and the Microenvironment in Breast Cancer Development and Prog... - 0 views

www.ncbi.nlm.nih.gov/...PMC3950899

cancer oxidative stress warburg effect reverse warburg effect ROS

shared by Nathan Goodyear on 11 Nov 14 - No Cached
  • oxidative stress leads to HIF-1α accumulation
  • Oxidative stress generated by breast cancer cells activates HIF-1α and NFκB in fibroblasts, leading to autophagy and lysosomal degradation of Cav-1
  • increased levels of hydrogen peroxide in exhaled breath condensate from patients with localized breast malignancy, associated with increased clinical severity
  • ...18 more annotations...
  • Comparing mitochondrial metabolic activity revealed a difference between stroma and epithelial cells
  • Overexpression of NOX4 in normal breast epithelial cells results in cellular senescence, resistance to apoptosis, and tumorigenic transformation, as well as increased aggressiveness of breast cancer cells
  • metalloproteinases (MMP) such as MMP-2, MMP-3, and MMP-9 increase extracellular matrix turnover and are themselves activated by oxidative stress
  • Lowered expression of Cav-1 not only leads to myofibroblast conversion and inflammation but also seems to impact aerobic glycolysis, leading to secretion of high energy metabolites such as pyruvate and lactate that drive mitochondrial oxidative phosphorylation in cancer cells
  • Reverse Warburg Effect
  • secreted transforming growth factor β (TGFβ), insulin-like growth factor (IGF), platelet-derived growth factor (PDGF), fibroblast growth factor 2, and stromal-derived factor 1 (SDF1) are able to activate fibroblasts and increase cancer cell proliferation
  • oxidative stress has an important role in the initiation and preservation of breast cancer progression
  • cancer preventive role of healthy mitochondria
  • the cancer cells produce hydrogen peroxide and by driving the “Reverse Warburg Effect” initiate oxidative stress in fibroblasts. As a result of this process, fibroblasts exhibited reduced mitochondrial activity, increased glucose uptake, ROS, and metabolite production.
  • Oxidative stress results from an imbalance between unstable reactive species lacking one or more unpaired electrons (superoxide anion, hydrogen peroxide, hydroxyl radical, reactive nitrogen species) and antioxidants
  • cancer cells are able to induce drivers of oxidative stress, autophagy and mitophagy: HIF-1α and NFκB in surrounding stroma fibro-blasts
  • Studies show that loss of Cav-1 in adjacent breast cancer stroma fibroblasts can be prevented by treatment with N-acetyl cysteine, quercetin, or metformin
  • However, diets rich in antioxidants have fallen short in sufficiently preventing cancer
  • hydrogen peroxide is one of the main factors that can push fibroblasts and cancer cells into senescence
  • It is widely held that HIF-1α function is dependent upon its location within the tumor microenvironment. It acts as a tumor promoter in CAFs and as a tumor suppressor in cancer cells
  • It was reported that overexpression of recombinant (SOD2) (Trimmer et al., 2011) or injection of SOD, catalase, or their pegylated counterparts can block recurrence and metastasis in mice
  • obstructing oxidative stress in the tumor microenvironment can lead to mitophagy and promote breast cancer shutdown is a promising discovery for the development of future therapeutic interventions.
  • Recent studies show that in the breast cancer microenvironment, oxidative stress causes mitochondrial dysfunction
  • Nathan Goodyear on 11 Nov 14
     
    Really fascinating article on tumor signaling. The article points to a complex signaling between cancer cells and stromal fibroblasts that results in myofibroblast transformation that increases the microenvironment favorability of cancer. This article points to oxidative stress as the primary driving force.  
Nathan Goodyear

The Ketogenic Diet and Sport: A Possible Marriage? : Exercise and Sport Sciences Reviews - 0 views

journals.lww.com/..._and_Sport___A_Possible.8.aspx

nutrition diet ketogenic ketogenic diet sports athletes exercise sports medicine

shared by Nathan Goodyear on 16 Nov 16 - No Cached
  • It is important to note that, although the blood level of glucose drops, it still remains at a physiological level (23), which is maintained through gluconeogenesis involving glucogenic amino acids and also glycerol released from triglycerides
  • “physiological ketosis” where KB levels may rise to 7 to 8 mmol L-1 (but without any pH change). In “pathological diabetic ketoacidosis,” on the other hand, ketonemia can exceed 20 mmol L-1 and also cause lowering of blood pH
  • in the initial phase of KD, about 16% of glucose comes from glycerol (released from triglyceride hydrolysis) and the bulk (60–65 g) from proteins via gluconeogenesis (proteins may be of either dietary or endogenous origin
  • ...5 more annotations...
  • the protein supply consumed during a KD “preserves,” as demonstrated, lean body mass
  • The importance of glycerol as a glucose source increases progressively during ketosis; in fact, glycerol passes from supplying 16% of total glucose to an average of 60% after many days (>7 d) of complete fasting (from 38% in lean individual to 79% in the obese).
  • The possible reasons for the effectiveness of KD for weight loss may be listed as follows, in order of evidence, strongest first: Figure 3Image Tools 1. Appetite reduction: protein satiety, effects on appetite-related hormones such as ghrelin, and possibly a sort of direct appetite-blocking effect of KB 2. Reduced lipogenesis and increased fat oxidation 3. A reduction in respiratory quotient may indicate a greater metabolic efficiency in fat oxidation 4. A thermic effect of proteins and increased energy usage by gluconeogenesis
  • all data regarding biochemical and molecular mechanisms suggest that it is very difficult to increase muscle mass during a KD; use of which really should be limited to the few days immediately before competition in bodybuilding.
  • a long-term KD can interfere with some muscle hypertrophy mechanisms and this could be counterproductive if the aim of the athlete is to gain muscle mass
  • Nathan Goodyear on 16 Nov 16
     
    Great read on the ketogenic  and its application to sports/training...
Nathan Goodyear

Inflammatory Mechanisms in Obesity - Annual Review of Immunology, 29(1):415 - 0 views

www.annualreviews.org/...annurev-immunol-031210-101322

obesity inflammation overweight endoplasmic reticulum stress

shared by Nathan Goodyear on 23 Jan 12 - No Cached
  • Nathan Goodyear on 23 Jan 12
     
    good review of inflammation-obesity link.  THis article also discusses endoplasmic reticulum stress associated with inflammation and obesity.  The result is decoupling of protein synthesis.  This article also discusses some anti-inflammatory therapies.  This link is for abstract only.  Full article is not available on line.  
Nathan Goodyear

Obesity - The Obesity Pandemic: Where Have We Been and Where Are We Going? - 0 views

www.nature.com/...oby2004273a.html

obesity pandemic inflammation inflammatory overweight weight-loss

shared by Nathan Goodyear on 20 Dec 11 - No Cached
  • Nathan Goodyear on 20 Dec 11
     
    nice study on contributors to the obesity epidemic.  Particularly inflammation.  This article touches on the idea that fat acts as a hormone producing organ.  Minus some of the treatment strategies, surgery and prescription drugs, this is a good article.   This article also touches on the implications of the obesity Pandemic as they state.
Nathan Goodyear

Antiobesity effects of green tea catechins: a mechanistic review - 0 views

www.jnutbio.com/...fulltext

green tea GTC green tea catechins obesity weight-loss

shared by Nathan Goodyear on 31 Jul 12 - No Cached
  • Nathan Goodyear on 31 Jul 12
     
    great article on the role/effects green tea catechins has on obesity.  These articles are great, because they actually show the biochemistry of the "natural" or "alternative" therapies.  
Nathan Goodyear

Hormone Balance in Males - 0 views

www.johnleemd.com/...male_hormone.html

hormone therapy hormonal BHRT testosterone estrogen estradiol andropause saliva testing salivary male hormones balance

shared by Nathan Goodyear on 10 Oct 11 - Cached
  • Nathan Goodyear on 10 Oct 11
     
    Fantastic article written by John Lee, MD.  This article is a great review on saliva testing and hormone therapy as it relates to both men and women; even though this article is in reference to men.  Worth your time to read
umar111

Computer Science: Computer hardware - 0 views

computersciencetopper.blogspot.com/...computer-hardware.html

Best computer computer computer Science it blog

shared by umar111 on 26 Apr 23 - No Cached
  • umar111 on 26 Apr 23
     
    Computer Science Tuesday, April 25, 2023 Computer hardware Computer hardware is the physical components that make up a computer system. It includes everything from the central processing unit (CPU) to the monitor, keyboard, and mouse. Understanding the different types of hardware and how they work together is essential for anyone who works with computers. In this article, we will explore the various components of computer hardware, including internal and external components, and the peripherals that connect to them. We will also discuss the importance of hardware maintenance, the latest advancements in computer technology, and factors to consider when choosing the right hardware for your needs. Whether you are a computer technician, a gamer, or simply someone who uses a computer for everyday tasks, this article will help you better understand the world of computer hardware. Introduction to Computer Hardware Computer hardware refers to the physical components that make up a computer system. It includes everything from the processor and memory to input/output devices such as the keyboard and monitor. In this article, we will explore the different types of computer hardware and their functions. What is Computer Hardware Computer hardware refers to the physical components of a computer system. It includes all the components that can be touched, seen, and used to interact with a computer, such as the monitor, keyboard, and mouse. Hardware is different from computer software, which refers to the programs and applications that run on a computer system. History of Computer Hardware The history of computer hardware dates back to the 1820s when Charles Babbage, an English mathematician, and inventor, designed the first analytical engine, which was considered to be the first mechanical computer. With time, more complex electronic computers were developed, including the first Intel microprocessor in 1971. Since then, computer hardware has continued to evolve, becoming
Nathan Goodyear

Nutritional protective mechanisms against gut inflammation - 0 views

www.jnutbio.com/...fulltext

nutritional gut inflammation PPAR-gamma IBD inflammatory bowel disease

shared by Nathan Goodyear on 07 Jun 13 - No Cached
  • Nathan Goodyear on 07 Jun 13
     
    Nice review of inflammation originating from the gut.  This article nicely points out the pathway involving PPAR gamma and its anti-inflammatory effects in gut inflammatory conditions such as IBD. This article also specifically discusses natural compounds that activate PPAR gamma and thus reduce inflammation.  Good deep biochemical discussion of how natural therapies reduce inflammation.  
Nathan Goodyear

ScienceDirect.com - Cell Metabolism - Estrogen Receptors and the Metabolic Network - 0 views

www.sciencedirect.com/...S1550413111003123

ER-alpha ER-beta estrogen receptor receptors metabolic syndrome MetS hormone hormones

shared by Nathan Goodyear on 11 Oct 12 - No Cached
  • The pro-opiomelanocortin (POMC) neurons have an anorexigenic action and, when activated, reduce food intake through the release of two peptides, α-melanocyte-stimulating hormone (α-MSH) and cocaine-and-amphetamine-regulated transcripts (CART). The neuropeptide Y (NPY) neurons, on the other hand, release NPY hormone and agouti gene-related protein (AgRP), which prevent the binding of α-MSH to MC3R and MC4R, increasing food intake
  • This suggests that the central anorexic effects of E2 may occur via ERβ
  • The main hypothalamic areas involved in food intake and satiety are the arcuate nucleus (ARC), the lateral hypothalamus (LH), the paraventricular nucleus (PVN), the ventromedial hypothalamus (VMH), and the dorsomedial hypothalamus (DMH)
  • ...22 more annotations...
  • Leptin is a potent anorexigenic and catabolic hormone secreted by adipose cells that reduces food intake and increases energy expenditure
  • E2 not only modulates leptin receptor mRNA in the ARC and VMH, but also increases hypothalamic sensitivity to leptin, altering peripheral fat distribution
  • ghrelin. It acts on growth hormone secretagogue receptors (GHSR1a) located in the ARC and is a potent stimulator of food intake
  • It thus appears that of the two ERs, ERα plays a predominant role in the CNS regulation of lipid and carbohydrate homeostasis.
  • Both ERs have been identified in the ARC
  • Stimulation of MCH neurons increases food intake and fat accumulation while its inhibition leads to decreased food intake and reduced fat accumulation.
  • Both ERs have been identified in the LH
  • both ERs have been identified in this nucleus
  • The PVN is the region of the hypothalamus with the highest expression of ERβ and is reported to be weakly ERα positive
  • The VMH is ERα regulated
  • Skeletal muscle is responsible for 75% of the insulin-induced glucose uptake in the body
  • GLUT4 is highly expressed in muscle and represents a rate-limiting step in the insulin-induced glucose uptake
  • data suggest that in the physiological range, E2 is beneficial for insulin sensitivity, whereas hypo- or hyperestrogenism is related to insulin resistance
  • In aging female rats, E2 treatment improves glucose homeostasis mainly through its ability to increase muscle GLUT4 content on the cell membrane
  • It is evident that ERα and ERβ have distinct actions and that much more research is needed to clearly identify the function of each receptor in muscle.
  • E2 prevents accumulation of visceral fat, increases central sensitivity to leptin, increases the expression of insulin receptors in adipocytes, and decreases the lipogenic activity of lipoprotein lipase in adipose tissue
  • In rats, ovariectomy increases body weight, intra-abdominal fat, fasting glucose and insulin levels, and insulin resistance followed by decreased phosphorylation of AMPK and its substrate acetyl-CoA carboxylase in adipose tissue
  • decreased adiponectin, PPARγ coactivator-1α (PGC-1α), and uncoupling protein 2 (UCP2) and increased resistin
  • Men with aromatase deficiency have truncal obesity, elevated blood lipids, and severe insulin resistance
  • Although not all studies are in agreement, polymorphisms of ERα in humans have been associated with risk factors for CVDs
  • Human subcutaneous and visceral adipose tissues express both ERα and ERβ, whereas only ERα mRNA has been identified in brown adipose tissue
  • suggesting that ERα is the main regulator of GLUT4 expression in adipose tissue
  • Nathan Goodyear on 11 Oct 12
     
    very nice article that looks at the balance of ER-alpha/ER-beta and their role in metabolic syndrome.  This article discusses the balance of  these receptors are tissue dependent in their effect.  I like their conclusion: "...but these mechanisms will never be completely understood if they are not considered in the context of a whole system.
Nathan Goodyear

Neuroprotection of Sex Steroids - 0 views

www.ncbi.nlm.nih.gov/...PMC3036837

hormones estrogen progesterone testosterone sex hormones brain neurology neuroprotection neuroprotective hormones hormone

shared by Nathan Goodyear on 10 Jul 12 - No Cached
  • Nathan Goodyear on 10 Jul 12
     
    great article on sex hormones and neuroprotection.  This article summarizes the research on estrogen, progesterone, and aromatase activity in in vitro and in vivo studies.  Additionally, the study reviews the androgenic neuroprotection in men.  Who has said that hormones are not needed post menopausal again?  Maybe, that is the sign that they need the neuroprotective effect of hormones.
Nathan Goodyear

Aromatase and regulating the estrogen:androgen ratio in the prostate gland - 0 views

www.sciencedirect.com/...S0960076009002696

estrogen estradiol Testosterone T:E2 prostate cancer prostate BPH male men hormone hormones cancer health ER alpha ER beta aromatase activity aromatase

shared by Nathan Goodyear on 21 Aug 13 - No Cached
  • Nathan Goodyear on 21 Aug 13
     
    This article summarizes it all.  With age, Testosterone declines and estrogen production, through elevated aromatase activity, increases.  This results in a decline in the Testosterone:estradiol ratio.  This has been clearly implicated in both benign and disease states of the prostate.  The evidence points to aromatase activity and estrogen in the prostate to poor prostate health.  Additionally, this article points out the impact of ER alpha and ER beta on the translation of the message of Estrogen.
Nathan Goodyear

Early repeated administration of progesterone improves the recovery of neuropathic pain... - 0 views

www.sciencedirect.com/...S0960076014000466

progesterone metabolites metabolism 5alpha-reductase neuroprotection brain CNS BHRT HRT pain neuropathic hormone hormones

shared by Nathan Goodyear on 24 Jun 14 - No Cached
  • Nathan Goodyear on 24 Jun 14
     
    Very interesting article.  Early Progesterone treatment, in animal model, shown to improve neuropathic pain recovery.  This is by no means the first study to show this.  This has been shown numerous times in TBI, but the timing of therapy was the purpose of this article.  What is very interesting here is that the metabolites implicated here in the recovery are the same metabolites implicated in an increased tumor potential.
Nathan Goodyear

Thyroid Hormone and Cardiac Disease: From Basic Concepts to Clinical Application - 0 views

www.ncbi.nlm.nih.gov/...PMC3134399

T3 cardiovascular death disease heart health MI myocardial infarction CHF heart failure thyroid hormone hormones hypothyroid hypothyroidism CVD

shared by Nathan Goodyear on 24 Sep 14 - No Cached
  • Nathan Goodyear on 24 Sep 14
     
    Low T3 post MI is associated with increased CHF, morbidity and mortality.  Article discusses thyroid hormones and cardiac function/remodeling post infarct.  The article also lays the ground work for a new study of T3 in patients post MI to be followed for 6 months.
Nathan Goodyear

International Tables of Glycemic Index and Glycemic Load Values: 2008 - 1 views

www.ncbi.nlm.nih.gov/...PMC2584181

glycemic index load

shared by Nathan Goodyear on 16 Aug 13 - No Cached
  • Nathan Goodyear on 16 Aug 13
     
    Great article from 2008 that discusses glycemic index and glycemic load.  What is great about this article is the supplementary appendix listing the above for > 1000 items.
Nathan Goodyear

From the Cover: Pharmacologic doses of ascorbate act as a prooxidant and decrease growt... - 0 views

www.ncbi.nlm.nih.gov/...PMC2516281

cancer IV intravenous vitamin C IV vitamin C

shared by Nathan Goodyear on 18 Sep 13 - No Cached
  • An extensive panel of 43 tumor and 5 normal cell lines were exposed to ascorbate in vitro for ≤2 h to mimic clinical pharmacokinetics
  • effective concentration that decreased survival 50% (EC50) was determined. EC50 was <10 mM for 75% of tumor cells tested, whereas cytotoxicity was not evident in normal cells with >20 mM ascorbate
  • The addition of catalase to the medium ameliorated death of ovarian carcinoma (Ovcar5), pancreatic carcinoma (Pan02), and glioblastoma (9L) cells exposed to 10 mM ascorbate (1 h), indicating cytotoxicity was mediated by H2O2
  • ...8 more annotations...
  • A treatment dose of 4 g ascorbate/kg body weight either once or twice daily did not produce any discernible adverse effects
  • Xenograft experiments showed that parenteral ascorbate as the only treatment significantly decreased both tumor growth and weight by 41–53%
  • Peak plasma concentrations of ascorbate approached 30 mM
  • Pharmacologic concentrations of ascorbate decreased tumor volumes 41–53% in diverse cancer types known for both their aggressive growth and limited treatment options.
  • Our findings showed that pharmacologic ascorbic acid concentrations were cytotoxic to many types of cancer cells in vitro (Fig. 1A) and significantly impeded tumor progression in vivo without toxicity to normal tissues
  • The amelioration of ascorbate cytotoxicity in vitro by the addition of catalase was consistent among sensitive cancer cells (Fig. 1B) and points unambiguously to H2O2 generation in the extracellular medium
  • the current in vivo data support that pharmacologic ascorbate concentrations, which can readily be achieved in humans (Fig. 3E), diminished growth of several aggressive cancer types in mice (Fig. 2) without causing apparent adverse effects.
  • These intratumoral H2O2 concentrations of >125 μM persisted for >3 h after ascorbate administration
  • Nathan Goodyear on 18 Sep 13
     
    Tumor xenograft model in mice finds reduction in growth rates of ovarian cancer, pancreatic cancer, and glioblastoma with daily IV vitamin C.
Nathan Goodyear

Vitamin C preferentially kills cancer stem cells in hepatocellular carcinoma via SVCT-2... - 0 views

www.nature.com/...s41698-017-0044-8

cancer cancer stem cells liver cancer vitamin C IV vitamin C oncology

shared by Nathan Goodyear on 30 Jan 18 - No Cached
  • Chen et al. have revealed that ascorbate at pharmacologic concentrations (0.3–20 mM) achieved only by intravenously (i.v.) administration selectively kills a variety of cancer cell lines in vitro, but has little cytotoxic effect on normal cells.
  • Ascorbic acid (the reduced form of vitamin C) is specifically transported into cells by sodium-dependent vitamin C transporters (SVCTs)
  • SVCT-1 is predominantly expressed in epithelial tissues
  • ...41 more annotations...
  • whereas the expression of SVCT-2 is ubiquitous
  • differential sensitivity to VC may result from variations in VC flow into cells, which is dependent on SVCT-2 expression.
  • high-dose VC significantly impaired both the tumorspheres initiation (Fig. 4d, e) and the growth of established tumorspheres derived from HCC cells (Fig. 4f, g) in a time-dependent and dose-dependent manner.
  • Hepatocellular carcinoma (HCC)
  • The antioxidant, N-acetyl-L-cysteine (NAC), preventing VC-induced ROS production (a ROS scavenger), completely restored the viability and colony formation among VC-treated cells
  • DNA double-strand damage was found following VC treatment
  • DNA damage was prevented by NAC
  • Interestingly, the combination of VC and cisplatin was even more effective in reducing tumor growth and weight
  • Consistent with the in vitro results, stemness-related genes expressions in tumor xenograft were remarkably reduced after VC or VC+cisplatin treatment, whereas conventional cisplatin therapy alone led to the increase of CSCs
  • VC is one of the numerous common hepatoprotectants.
  • Interestingly, at extracellular concentrations greater than 1 mM, VC induces strong cytotoxicity to cancer cells including liver cancer cells
  • we hypothesized that intravenous VC might reduce the risk of recurrence in HCC patients after curative liver resection.
  • Intriguingly, the 5-year disease-free survival (DFS) for patients who received intravenous VC was 24%, as opposed to 15% for no intravenous VC-treated patients
  • Median DFS time for VC users was 25.2 vs. 18 months for VC non-users
  • intravenous VC use is linked to improved DFS in HCC patients.
  • In this study, based on the elevated expression of SVCT-2, which is responsible for VC uptake, in liver CSCs, we revealed that clinically achievable concentrations of VC preferentially eradicated liver CSCs in vitro and in vivo
    • Nathan Goodyear
      Nathan Goodyear on 31 Jan 18
       
      the authors here made similar mistakes to the Mayo authors i.e. under doses here in this study.  They dosed at only 2 grams IVC.  A woefully low dose of IVC.
  • Additionally, we found that intravenous VC reduced the risk of post-surgical HCC progression in a retrospective cohort study.
    • Nathan Goodyear
      Nathan Goodyear on 31 Jan 18
       
      positive results despite a low dose used.
    • Nathan Goodyear
      Nathan Goodyear on 31 Jan 18
       
      Their comfort zone was 1mM.  They should have targeted 20-40 mM.
  • Three hundred thirty-nine participants (55.3%) received 2 g intravenous VC for 4 or more days after initial hepatectomy
  • As the key protein responsible for VC uptake in the liver, SVCT-2 played crucial roles in regulating the sensitivity to ascorbate-induced cytotoxicity
  • we also observed that SVCT-2 was highly expressed in human HCC samples and preferentially elevated in liver CSCs
  • SVCT-2 might serve as a potential CSC marker and therapeutic target in HCC
  • CSCs play critical roles in regulating tumor initiation, relapse, and chemoresistance
  • we revealed that VC treatment dramatically reduced the self-renewal ability, expression levels of CSC-associated genes, and percentages of CSCs in HCC, indicating that CSCs were more susceptible to VC-induced cell death
  • as a drug for eradicating CSCs, VC may represent a promising strategy for treatment of HCC, alone or particularly in combination with chemotherapeutic drugs
  • In HCC, we found that VC-generated ROS caused genotoxic stress (DNA damage) and metabolic stress (ATP depletion), which further activated the cyclin-dependent kinase inhibitor p21, leading to G2/M phase cell cycle arrest and caspase-dependent apoptosis in HCC cells
  • we demonstrated a synergistic effect of VC and chemotherapeutic drug cisplatin on killing HCC both in vitro and in vivo
  • Intravenous VC has also been reported to reduce chemotherapy-associated toxicity of carboplatin and paclitaxel in patients,38 but the specific mechanism needs further investigation
    • Nathan Goodyear
      Nathan Goodyear on 31 Jan 18
       
      so, exclude the benefit to patients until the exact mechanism of action, which will never be fully elicited?!?!?
  • Our retrospective cohort study also showed that intravenous VC use (2 g) was related to the improved DFS in HCC patients after initial hepatectomy
    • Nathan Goodyear
      Nathan Goodyear on 31 Jan 18
       
      Terribly inadequate dose.  Target is 20-40 mM which other studies have found occur with 50-75 grams of IVC.
  • several clinical trials of high-dose intravenous VC have been conducted in patients with advanced cancer and have revealed improved quality of life and prolonged OS
  • high-dose VC was not toxic to immune cells and major immune cell subpopulations in vivo
  • high recurrence rate and heterogeneity
  • tumor progression, metastasis, and chemotherapy-resistance
  • SVCT-2 was highly expressed in HCC samples in comparison to peri-tumor tissues
  • high expression (grade 2+/3+) of SVCT-2 was in agreement with poorer overall survival (OS) of HCC patients (Fig. 1c) and more aggressive tumor behavior
  • SVCT-2 is enriched in liver CSCs
  • these data suggest that SVCT-2 is preferentially expressed in liver CSCs and is required for the maintenance of liver CSCs.
  • pharmacologic concentrations of plasma VC higher than 0.3 mM are achievable only from i.v. administration
  • The viabilities of HCC cells were dramatically decreased after exposure to VC in dose-dependent manner
  • VC and cisplatin combination further caused cell apoptosis in tumor xenograft
  • These results verify that VC inhibits tumor growth in HCC PDX models and SVCT-2 expression level is associated with VC response
  • qPCR and IHC analysis demonstrated that expression levels of CSC-associated genes and percentages of CSCs in PDXs dramatically declined after VC treatment, confirming the inhibitory role of VC in liver CSCs
  • Nathan Goodyear on 30 Jan 18
     
    IV vitamin C in vitro and in vivo found to "preferentially" eradicate cancer stem cells.  In addition, IV vitamin C was found to be adjunctive to chemotherapy, found to be hepatoprotectant.  This study also looked at SVCT-2, which is the transport protein important in liver C uptake.
Nathan Goodyear

Going viral: a review of replication-selective oncolytic adenoviruses - PMC - 0 views

www.ncbi.nlm.nih.gov/...PMC4652981

oncolytic therapy oncolytic virus cancer spontaneous regression oncolytic virotherapy spontaneous tumor regression

shared by Nathan Goodyear on 14 Jul 23 - No Cached
  • Nathan Goodyear on 14 Jul 23
     
    The plurality of this article is around the concept of oncolytic therapy; yet, the article mentions the documentation of a influenza induced spontaneous remission of leukemia.
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