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Nathan Goodyear

Journal of Endocrinological Investigation - 0 views

www.jendocrinolinvest.it/...abstract.cfm

diabetes

shared by Nathan Goodyear on 28 May 13 - No Cached
  • Nathan Goodyear on 28 May 13
     
    Just an abstract, but the call for customized/individualized treatment strategies called for those with diabetes.  Medicine is moving to an individualized paradigm rather than a herd mentality.
Nathan Goodyear

Journal of Endocrinological Investigation - 0 views

www.jendocrinolinvest.it/...abstract.cfm

birth control oral contraceptives cardiovascular risk PCOS polycystic ovary syndrome

shared by Nathan Goodyear on 28 May 13 - No Cached
  • Nathan Goodyear on 28 May 13
     
    The point of this post is not that the author concludes that metformin an statin therapy should be used in PCOS women on birth control with elevated cardiovascular risk; but that with struggling with PCOS should have cardiovascular risk assessment prior to starting birth control.  Again, back to the individualized approach paradigm.
Nathan Goodyear

Digestive Diseases and Sciences, Volume 57, Number 5 - SpringerLink - 0 views

www.springerlink.com/...5

IBS probiotics dysbiosis

shared by Nathan Goodyear on 31 May 12 - No Cached
  • Nathan Goodyear on 31 May 12
     
    study shows that IBS related to dysbiosis, imbalanced microbial population, in the small intestine.  But, as they always do, their thought of treatment is via the old paradigm.  How, about just restoring the bacterial balance with probiotics, which, themselves will kill the unwelcomed bacteria.
Nathan Goodyear

America's State of Mind: New Report Finds Americans Increasingly Turn to Medications to... - 0 views

medco.mediaroom.com/index.php

antipsychotics medications america americans antidepressants antianxiety

shared by Nathan Goodyear on 17 Nov 11 - No Cached
  • Nathan Goodyear on 17 Nov 11
     
    Our current health care paradigm is failing us!  20% of women are on anti-depressants and 1 in 4 American women are on some psychiatric medicine.  And we wonder why we are unhealthy?
Nathan Goodyear

Randomized controlled trial of maternal omega-3 long-chain PUFA supplementation during ... - 0 views

ajcn.nutrition.org/...ajcn.113.069203.abstract

pregnancy n-3 omega-3 omega 3 DHA docosahexaenoic acid attention memory

shared by Nathan Goodyear on 27 Feb 14 - No Cached
  • Nathan Goodyear on 27 Feb 14
     
    randomized study finds no difference in attention, memory in children born to mothers supplementing with DHA.  Good randomized design, but several problems.  First, did these women need supplementation.  No testing was done to determine need.  They may have needed more or none at all--the standard throw a dart on the wall and hope it sticks paradigm.  Second, Neurologcial development starts from day one, so do properly determine effect, the authors need to start support at conception or even better- before.  This follows that logic that women desiring conception should start extra folic acid 3 months prior. The literature is moving in the right direction, but they are still limiting themselves.  
Nathan Goodyear

Interview with Dr Andrew Wakefield - the structure of scientific revolutions - NaturalN... - 0 views

naturalnews.tv/v.asp

Dr. Wakefield vaccinations

shared by Nathan Goodyear on 09 Feb 11 - No Cached
  • Nathan Goodyear on 09 Feb 11
     
    Great interview with Dr. Andrew Wakefield regarding science, vaccinations, and paradigms, and scientific revolutions
Nathan Goodyear

A mitochondrial paradigm for degenerative diseases... [Novartis Found Symp. 2001] - Pub... - 0 views

www.ncbi.nlm.nih.gov/...11280029

mitochondrial paradigm

shared by Nathan Goodyear on 08 Feb 11 - No Cached
  • the decline of mitochondrial energy production resulting in increased oxidative stress and apoptosis does play a significant role in degenerative diseases and ageing.
  • Nathan Goodyear on 08 Feb 11
     
    oxidative stress leads to decreased mitochondrial energy production, which results in cell death, and thus aging.
Nathan Goodyear

Chemotherapy-Exacerbated Breast Cancer Metastasis: A Paradox Explainable by Dysregulate... - 0 views

www.ncbi.nlm.nih.gov/...PMC6274941

chemotherapy metastasis

shared by Nathan Goodyear on 06 Jul 19 - No Cached
  • Nathan Goodyear on 06 Jul 19
     
    Time to rethink the paradigm of cancer treatment with chemotherapy.
Nathan Goodyear

Hyperbaric oxygen therapy promotes neurogenesis: where do we stand? - 0 views

www.ncbi.nlm.nih.gov/...PMC3231808

hbot hyperbaric therapy hyperbaric brain TBI stroke neurogenesis neuorplasticity

shared by Nathan Goodyear on 18 May 17 - No Cached
  • Numerous in vivo and in vitro studies confirm that HBOT induces neurogenesis
  • HIF-1α is the principal mediator of cellular hypoxia adaptations
  • activated by hypoxia, HIF-1α causes the transcription of its regulated downstream genes, including erythropoietin (EPO) and VEGF which are known to promote neurogenesis
  • ...10 more annotations...
  • The safety of HBOT was also evaluated and it was pointed out that, if given at proper paradigms, like 1.5 ATA for 60 minutes, HBOT will not cause oxygen toxicity
  • Rockswold et al., on the other hand, found that HBOT might be potentially beneficial for severe TBI patients
  • McDonagh et al., concluded that there was insufficient evidence to establish the effectiveness of HBOT in the treatment of TBI
  • The first multicenter, randomized, double-blind, controlled trial in 2009 found that 40-hour HBOT of 24% oxygen at 1.3 ATM produced significant improvement in children's overall functioning, receptive language, social interaction, eye contact, and sensory/cognitive awareness compared to those received slightly pressurized room air
  • Another study in 2010 on 16 autism patients, adopting a similar treatment paradigm, showed no effect on a wide array of behavioral evaluations
  • To date, there is little evidence that HBOT causes malignant growth or metastasis. A history of malignancy should therefore not be considered as a contraindication for HBOT
  • HBOT enhances the production of reactive oxygen species (ROS) and causes oxidative stress in body tissues
  • Excessive accumulation of oxidative stress may contribute to neurodegenerative processes and cell death in the brain, as seen in diseases like Alzheimer's disease (AD) and Parkinson's disease (PD)
  • Hormesis
  • process that results in a functional improvement of cellular stress resistance, survival, and longevity in response to sub-lethal levels of stress
  • Nathan Goodyear on 18 May 17
     
    great review of hbot, brain injury, neuroplasticity and neurogenesis.
Nathan Goodyear

The Placenta Harbors a Unique Microbiome | Science Translational Medicine - 0 views

stm.sciencemag.org/...237ra65.short

placenta pregnancy gut gut bacteria gut flora gut health gut microbiome gut microbiota

shared by Nathan Goodyear on 16 Jun 17 - No Cached
  • Nathan Goodyear on 16 Jun 17
     
    Paradigm shift: placenta is not sterile environment but contains bacteria from mother.  This microbiome may play role in the initiation of the offsprings gut micro biome.
spineneuro

Top Dr. Vipul Gupta on Paradigm Shifts in Medical Care During COVID-19 Pandemic - 0 views

www.briefingwire.com/...-care-during-covid-19-pandemic

top Dr. Vipul Gupta low-cost interventional neurologist radiologist Artemis hospital Gurgaon Best Interventional Neurologist in Delhi India Dr. Vipul Gupta India Dr. Vipul Gupta Contact Number

shared by spineneuro on 02 Oct 21 - No Cached
  • spineneuro on 02 Oct 21
     
    "Brain cerebrovascular accident care is now exploding with the new system and alternatives, just as heart cerebrovascular accident care grew unexpectedly within the 1990s," said top Dr. Vipul Gupta Neurologist. Appointment with Dr. Vipul Gupta Artemis Call 91-9325887033 Email id: dr.vipulgupta@neurospinehospital.com.
Nathan Goodyear

Telomerase at the intersection of cancer and aging - 0 views

www.ncbi.nlm.nih.gov/...PMC3896987

telomere telomeres telomerase telomerase activator aging disease cancer

shared by Nathan Goodyear on 18 May 16 - No Cached
  • The anti-aging role of telomerase has been demonstrated to be largely mediated by its canonical role in elongating telomeres, which prevents the accumulation of critically short telomeres and loss of tissue homeostasis
  • Short telomeres, and subsequent DDR activation, could occur both in cancer and aging
  • increased abundance of short telomeres correlates with higher genomic instability and decreased longevity in various organisms, including mice, zebrafish, and yeast
  • ...15 more annotations...
  • mice deficient for telomerase or for telomere binding proteins are characterized by accelerated age-related defects
  • In humans, short telomeres are considered good indicators of an individual’s health status and correlate with both genetic and environmental factors
  • Although recent findings strongly support the idea that short telomeres drive several age-related diseases 38 we cannot exclude the possibility that in some situations short telomeres may be a consequence of the disease itself.
  • the current view is that telomerase deficiency may contribute to the early steps of cancer development by fueling chromosomal instability, while subsequent activation of telomerase may be necessary to allow tumor growth and tumor progression towards more malignant states
  • telomerase activation can be an early event in cancer, it is not necessary for cancer initiation
  • telomerase can stimulate tumor progression by ensuring maintenance of telomeres above a critically short length, thus preventing induction of cellular senescence or apoptosis
  • Almost all human cancers present activation of telomerase as a hallmark, most likely as a mechanism to allow unlimited cell proliferation of tumor cells
  • recent evidence demonstrated that short telomeres alone could lead to genomic instability and cancer
  • Getting rid of telomerase can also be problematic; the lack of telomerase could lead to increased chromosomal instability, which in turn could be at the basis for cancer initiation when tumor suppressor barriers are bypassed
  • telomerase activation is a potential therapeutic strategy for the treatment of age-related diseases
  • telomerase activation in adult or old mice by means of a gene therapy strategy was shown to be sufficient to improve metabolic fitness, neuromuscular capacity, and prevent bone loss, as well as significantly increase both median and maximum longevity, without increased cancer incidence
  • These studies suggest that telomerase expression could be considered a feasible approach to reverse tissue dysfunction and extend healthy lifespan without increasing cancer incidence
  • humans almost completely lose telomerase activity from somatic tissues in the adulthood
  • a change of paradigm seems to be occurring in telomerase biology, with a switch from viewing telomerase as fueling cancer to reversing aging
  • Telomerase expression in a background of high levels of tumor suppressors or in aged organisms seems to prevent its expected pro-cancer activity and yet it still functions as an anti-aging factor
  • Nathan Goodyear on 18 May 16
     
    Telomerase activity and longer telomere length is shown to correlated inversely with many chronic diseases of aging.  In contrast, telomerase activity is found to be involved in carcinogenesis.  Increased carcinogenic potential of telomerase activity has not borne out in studies.  In addition, increased CD8 cell activity as a result of telomerase activation will actually decrease carcinogenic potential via NK activation.
Nathan Goodyear

Effect of Coenzyme Q10 on Th1/Th2 Paradigm in Females with Idiopathic Recurrent Pregnan... - 0 views

www.ncbi.nlm.nih.gov/...25800618

CoQ10 pregnancy inflammation IFN-gamma

shared by Nathan Goodyear on 25 Apr 16 - No Cached
  • Nathan Goodyear on 25 Apr 16
     
    CoQ10 reduced Th1 inflammatory cytokines in those women with recurrent early pregnancy loss.  CoQ10 specifically, reduced IFN-gamma.
Nathan Goodyear

Tight Junctions, Intestinal Permeability, and Autoimmunity Celiac Disease and Type 1 Di... - 0 views

www.ncbi.nlm.nih.gov/...PMC2886850

gut flora microbiota bacteroides bifidobacterium lactobacillus dysbiosis leaky celiac disease diabetes

shared by Nathan Goodyear on 29 Feb 12 - No Cached
  • Nathan Goodyear on 29 Feb 12
     
    this study from 2009 showed how disrupted/imbalanced gut flora leads to leaky gut.  This case, high bacteroides relative to bifidobacterium and lactobacillus resulted in disruption of the zonulin pathway and thus lncreased intestinal permeability.
Nathan Goodyear

Cytokine profiles in localized scleroderma and relationship to clinical features - 0 views

www.ncbi.nlm.nih.gov/...PMC3632442

morphea autoimmune disease children scleroderma inflammation

shared by Nathan Goodyear on 22 Jan 14 - No Cached
  • Evaluation of the literature reveals a Th2 predominant cytokine profile in the biological specimens (sera, PBMCs, and tissue) of those with SSc
  • the literature available from studies in LS show that Th1, Th2, and Th17 cytokines may contribute equally to the pathogenesis of the disease
  • Classically, Th1 cells have been known to secrete IL-2, IFN-γ, and TNF-α, and are stimulated by IL-2 and IL-12
  • ...3 more annotations...
  • Th2 cells have been shown to be activated by IL-4 and produce IL-4, IL-5, IL-10 and IL-13
  • Th17 cells, a more recently identified Th cell subset that has altered the classic Th1/Th2 paradigm, produce IL-17 A/F, IL-21, and IL-22. IL-1, IL-6, IL-23, and TGF-β are now known to play important roles in the differentiation and propagation of the Th17 cell lineage
  • there is an overall notion that pro-inflammatory Th1 and Th17 associated cytokines are elevated during the early stages of scleroderma, whereas Th2 cytokines mainly correlate with disease damage and fibrosis extent
  • Nathan Goodyear on 22 Jan 14
     
    morphea
Nathan Goodyear

Inflammatory cause of metabolic syndrome via brain stress and NF-κB - 0 views

www.ncbi.nlm.nih.gov/...PMC3314172

metabolic syndrome TLR cytokines hypothalamus brain neurology metabolic syndrome NF-kappaB DIO diet induced obesity over nutrition nutrition inflammation

shared by Nathan Goodyear on 09 Jul 13 - No Cached
  • Mechanistic studies further showed that such metabolic inflammation is related to the induction of various intracellular stresses such as mitochondrial oxidative stress, endoplasmic reticulum (ER) stress, and autophagy defect under prolonged nutritional excess
  • intracellular stress-inflammation process for metabolic syndrome has been established in the central nervous system (CNS) and particularly in the hypothalamus
  • the CNS and the comprised hypothalamus are known to govern various metabolic activities of the body including appetite control, energy expenditure, carbohydrate and lipid metabolism, and blood pressure homeostasis
  • ...56 more annotations...
  • Reactive oxygen species (ROS) refer to a class of radical or non-radical oxygen-containing molecules that have high oxidative reactivity with lipids, proteins, and nucleic acids
  • a large measure of intracellular ROS comes from the leakage of mitochondrial electron transport chain (ETC)
  • Another major source of intracellular ROS is the intentional generation of superoxides by nicotinamide adenine dinucleotide phosphate (NADPH) oxidase
  • there are other ROS-producing enzymes such as cyclooxygenases, lipoxygenases, xanthine oxidase, and cytochrome p450 enzymes, which are involved with specific metabolic processes
  • To counteract the toxic effects of molecular oxidation by ROS, cells are equipped with a battery of antioxidant enzymes such as superoxide dismutases, catalase, peroxiredoxins, sulfiredoxin, and aldehyde dehydrogenases
  • intracellular oxidative stress has been indicated to contribute to metabolic syndrome and related diseases, including T2D [72; 73], CVDs [74-76], neurodegenerative diseases [69; 77-80], and cancers
  • intracellular oxidative stress is highly associated with the development of neurodegenerative diseases [69] and brain aging
  • dietary obesity was found to induce NADPH oxidase-associated oxidative stress in rat brain
  • mitochondrial dysfunction in hypothalamic proopiomelanocortin (POMC) neurons causes central glucose sensing impairment
  • Endoplasmic reticulum (ER) is the cellular organelle responsible for protein synthesis, maturation, and trafficking to secretory pathways
  • unfolded protein response (UPR) machinery
  • ER stress has been associated to obesity, insulin resistance, T2D, CVDs, cancers, and neurodegenerative diseases
  • brain ER stress underlies neurodegenerative diseases
  • under environmental stress such as nutrient deprivation or hypoxia, autophagy is strongly induced to breakdown macromolecules into reusable amino acids and fatty acids for survival
  • intact autophagy function is required for the hypothalamus to properly control metabolic and energy homeostasis, while hypothalamic autophagy defect leads to the development of metabolic syndrome such as obesity and insulin resistance
  • prolonged oxidative stress or ER stress has been shown to impair autophagy function in disease milieu of cancer or aging
  • TLRs are an important class of membrane-bound pattern recognition receptors in classical innate immune defense
  • Most hypothalamic cell types including neurons and glia cells express TLRs
  • overnutrition constitutes an environmental stimulus that can activate TLR pathways to mediate the development of metabolic syndrome related disorders such as obesity, insulin resistance, T2D, and atherosclerotic CVDs
  • Isoforms TLR1, 2, 4, and 6 may be particularly pertinent to pathogenic signaling induced by lipid overnutrition
  • hypothalamic TLR4 and downstream inflammatory signaling are activated in response to central lipid excess via direct intra-brain lipid administration or HFD-feeding
  • overnutrition-induced metabolic derangements such as central leptin resistance, systemic insulin resistance, and weight gain
  • these evidences based on brain TLR signaling further support the notion that CNS is the primary site for overnutrition to cause the development of metabolic syndrome.
  • circulating cytokines can limitedly travel to the hypothalamus through the leaky blood-brain barrier around the mediobasal hypothalamus to activate hypothalamic cytokine receptors
  • significant evidences have been recently documented demonstrating the role of cytokine receptor pathways in the development of metabolic syndrome components
  • entral administration of TNF-α at low doses faithfully replicated the effects of central metabolic inflammation in enhancing eating, decreasing energy expenditure [158;159], and causing obesity-related hypertension
  • Resistin, an adipocyte-derived proinflammatory cytokine, has been found to promote hepatic insulin resistance through its central actions
  • both TLR pathways and cytokine receptor pathways are involved in central inflammatory mechanism of metabolic syndrome and related diseases.
  • In quiescent state, NF-κB resides in the cytoplasm in an inactive form due to inhibitory binding by IκBα protein
  • IKKβ activation via receptor-mediated pathway, leading to IκBα phosphorylation and degradation and subsequent release of NF-κB activity
  • Research in the past decade has found that activation of IKKβ/NF-κB proinflammatory pathway in metabolic tissues is a prominent feature of various metabolic disorders related to overnutrition
  • it happens in metabolic tissues, it is mainly associated with overnutrition-induced metabolic derangements, and most importantly, it is relatively low-grade and chronic
  • this paradigm of IKKβ/NF-κB-mediated metabolic inflammation has been identified in the CNS – particularly the comprised hypothalamus, which primarily accounts for to the development of overnutrition-induced metabolic syndrome and related disorders such as obesity, insulin resistance, T2D, and obesity-related hypertension
  • evidences have pointed to intracellular oxidative stress and mitochondrial dysfunction as upstream events that mediate hypothalamic NF-κB activation in a receptor-independent manner under overnutrition
  • In the context of metabolic syndrome, oxidative stress-related NF-κB activation in metabolic tissues or vascular systems has been implicated in a broad range of metabolic syndrome-related diseases, such as diabetes, atherosclerosis, cardiac infarct, stroke, cancer, and aging
  • intracellular oxidative stress seems to be a likely pathogenic link that bridges overnutrition with NF-κB activation leading to central metabolic dysregulation
  • overnutrition is an environmental inducer for intracellular oxidative stress regardless of tissues involved
  • excessive nutrients, when transported into cells, directly increase mitochondrial oxidative workload, which causes increased production of ROS by mitochondrial ETC
  • oxidative stress has been shown to activate NF-κB pathway in neurons or glial cells in several types of metabolic syndrome-related neural diseases, such as stroke [185], neurodegenerative diseases [186-188], and brain aging
  • central nutrient excess (e.g., glucose or lipids) has been shown to activate NF-κB in the hypothalamus [34-37] to account for overnutrition-induced central metabolic dysregulations
  • overnutrition can present the cell with a metabolic overload that exceeds the physiological adaptive range of UPR, resulting in the development of ER stress and systemic metabolic disorders
  • chronic ER stress in peripheral metabolic tissues such as adipocytes, liver, muscle, and pancreatic cells is a salient feature of overnutrition-related diseases
  • recent literature supports a model that brain ER stress and NF-κB activation reciprocally promote each other in the development of central metabolic dysregulations
  • when intracellular stresses remain unresolved, prolonged autophagy upregulation progresses into autophagy defect
  • autophagy defect can induce NF-κB-mediated inflammation in association with the development of cancer or inflammatory diseases (e.g., Crohn's disease)
  • The connection between autophagy defect and proinflammatory activation of NF-κB pathway can also be inferred in metabolic syndrome, since both autophagy defect [126-133;200] and NF-κB activation [20-33] are implicated in the development of overnutrition-related metabolic diseases
  • Both TLR pathway and cytokine receptor pathways are closely related to IKKβ/NF-κB signaling in the central pathogenesis of metabolic syndrome
  • Overnutrition, especially in the form of HFD feeding, was shown to activate TLR4 signaling and downstream IKKβ/NF-κB pathway
  • TLR4 activation leads to MyD88-dependent NF-κB activation in early phase and MyD88-indepdnent MAPK/JNK pathway in late phase
  • these studies point to NF-κB as an immediate signaling effector for TLR4 activation in central inflammatory response
  • TLR4 activation has been shown to induce intracellular ER stress to indirectly cause metabolic inflammation in the hypothalamus
  • central TLR4-NF-κB pathway may represent one of the early receptor-mediated events in overnutrition-induced central inflammation.
  • cytokines and their receptors are both upstream activating components and downstream transcriptional targets of NF-κB activation
  • central administration of TNF-α at low dose can mimic the effect of obesity-related inflammatory milieu to activate IKKβ/NF-κB proinflammatory pathways, furthering the development of overeating, energy expenditure decrease, and weight gain
  • the physiological effects of IKKβ/NF-κB activation seem to be cell type-dependent, i.e., IKKβ/NF-κB activation in hypothalamic agouti-related protein (AGRP) neurons primarily leads to the development of energy imbalance and obesity [34]; while in hypothalamic POMC neurons, it primarily results in the development of hypertension and glucose intolerance
  • the hypothalamus, is the central regulator of energy and body weight balance [
  • Nathan Goodyear on 09 Jul 13
     
    Great article chronicles the biochemistry of "over nutrition" and inflammation through NF-kappaB activation and its impact on the brain.
Nathan Goodyear

PLOS ONE: Probiotic Microbes Sustain Youthful Serum Testosterone Levels and Testicular ... - 0 views

journals.plos.org/...article

hormone hormones low T low Testosterone hypogonadism Testosterone probiotic L reuters probiotics Lactobacillus lactobacillus reuteri male aging

shared by Nathan Goodyear on 29 Apr 15 - No Cached
  • Studies in both humans and rodents, however, suggest that low testosterone is due to age-related lesions in testes rather than irregular luteinizing hormone metabolism
  • Various dietary factors and diet-induced obesity have been shown to increase the risk for late onset male hypogonadism and low testosterone production in both humans and mice
  • Testosterone deficiency and metabolic diseases such as obesity appear to inter-digitate in complex cause-and-effect relationships
  • ...28 more annotations...
  • dietary supplementation of aged mice with the probiotic bacterium Lactobacillus reuteri makes them appear to be younger than their matched untreated sibling mice
  • These results indicate that gut microbiota induce modulation of local gastrointestinal immunity resulting in systemic effects on the immune system which activate metabolic pathways that restore tissue homeostasis and overall health
  • all these studies we consistently observed that young and aged mice consuming purified L. reuteri organisms had particularly large testes and a dominant male behavior.
  • The testes of probiotic-fed aged mice were rescued from both seminiferous tubule atrophy and interstitial Leydig cell area reduction typical of the normal aging process. Preservation of testicular architecture despite advanced age or high-fat diet coincided with remarkably high levels of circulating testosterone. The beneficial effects of probiotic consumption were recapitulated by the depletion of the pro-inflammatory cytokine Il-17.
  • feeding of L. reuteri consistently increased the gonadal weights, consumption of a non-pathogenic strain of Escherichia coli (E. coli) K12 organisms did not affect testicular weight
  • mice with dietary L. reuteri supplements were rescued from diet-induced obesity and had normal body weight and lean physique
  • Despite the comparable numbers of ST profiles, we determined that testes from L. reuteri-treated mice had increased ST cross-sectioned profiles
  • the probiotic organism induced prominent Leydig cell accumulations in the interstitial tissue between the ST's
  • The probiotic-associated increase of interstitial Leydig cell areas was sustained with advancing age at 7 (CD vs CD+LR, P = 0.0025; CD+E.coli vs CD+LR, P = 0.0251) and 12 months
  • mice eating L. reuteri had profoundly increased levels of circulating testosterone regardless of the type of diet they consumed
  • blocking pro-inflammatory Il-17 signaling entirely recapitulates the beneficial effects of probiotics
  • previous studies we found that dietary probiotics counteract obesity [19] and age-related integumentary pathology [18] at least in part by down-regulating systemic pro-inflammatory IL-17A-dependent signaling
  • Testes histomorphometry and serum androgen concentration data were both suggestive of a probiotic-associated up-regulation of spermatogenesis in mice
  • Lactobacillus reuteri we discovered that aging male animals had larger testes compared to their age-matched controls
  • xamined testes of probiotic microbe-fed mice and found that they had less testicular atrophy coinciding with higher levels of circulating testosterone compared to their age-matched controls
  • Similar testicular health benefits were produced using systemic depletion of the pro-inflammatory cytokine Il-17 alone, implicating a chronic inflammatory pathway in hypogonadism
  • One specific aspect of this paradigm is reciprocal activities of pro-inflammatory Th-17 and anti-inflammatory Treg cells
  • Feeding of L. reuteri organisms was previously shown to up-regulate IL-10 levels and reduce levels of IL-17 [19] serving to lower systemic inflammation
  • insufficient levels of IL-10 may increase the risk for autoimmunity, obesity, and other inflammatory disease syndromes
  • Westernized diets are also low in vitamin D, a nutrient that when present normally works together with IL-10 to protect against inflammatory disorders
  • Physiological feedback loops apparently exist between microbes, host hormones, and immunity
  • The hormone testosterone has been shown to act directly through androgen receptors on CD4+ cells to increase IL-10 expression
  • studies in both humans and rodents suggest that hypogonadism is due to age-related lesions in testes rather than irregular LH metabolism
  • We postulate that probiotic gut microbes function symbiotically with their mammalian hosts to impart immune homeostasis to maintain systemic and testicular health [34]–[35] despite suboptimal dietary conditions.
  • Dietary factors and diet-induced obesity were previously shown to increase risk for age-associated male hypogonadism, reduced spermatogenesis, and low testosterone production in both humans and mice [2]–[4], [8]–[11], [14]–[17], phenotypic features that in this study were inhibited by oral probiotic therapy absent milk sugars, extra protein, or vitamin D supplied in yogurt.
  • Similar beneficial effects of probiotic microbes on testosterone levels and sperm indices were reported in male mice that had been simultaneously supplemented with selenium
  • L. reuteri-associated prevention of age- and diet-related testicular atrophy correlates with increased numbers and size of Leydig cells
  • the initial changes of testicular atrophy begin to occur in mice from the age of 6 moths onwards [7] and indicates that the trophic effect of L. reuteri on Leydig cells is a key event which precedes and prevents age-related changes in the testes of mice. This effect is reminiscent of earlier studies describing Leydig cell hyperplasia and/or hypertrophy in the mouse and the rat testis that were achievable by the administration of gonadotropins, including human chorionic gonadotropin, FSH and LH
  • Nathan Goodyear on 29 Apr 15
     
    Fascinating study on how the addition of Lactobacillus reuteri increased Testicular size, prevented testicular atrophy, increased serum Testosterone production and protected against diet-induced/obesity-induced hypogonadism.  This was a mouse model
Nathan Goodyear

[Testosterone replacement therapy and prostate cancer: the downfall of a paradigm?]. - ... - 0 views

www.ncbi.nlm.nih.gov/...25919660

Testosterone prostate cancer hormone hormones

shared by Nathan Goodyear on 18 May 15 - No Cached
  • Nathan Goodyear on 18 May 15
     
    In this time of evidence-based medicine, the prevailing therapy that Testosterone causes prostate cancer is devoid of evidence.
Nathan Goodyear

Cellular and Molecular Basis of Deiodinase-Regulated Thyroid Hormone Signaling: Endocri... - 0 views

press.endocrine.org/...er.2008-0019

thyroid deiodinase T3 T4 hormone hormones

shared by Nathan Goodyear on 24 Nov 14 - No Cached
  • From a broad perspective, this paradigm can be seen as an example of how hormones are activated or inactivated in a controlled fashion in specific extraglandular tissues, in an analogous role to 5α-reductase and P450 aromatase in sex steroid metabolism and to 11β-hydroxysteroid dehydrogenase in glucocorticoid metabolism.
  • Nathan Goodyear on 24 Nov 14
     
    better source for previous post on thyroid metabolism and deiodinase.
Nathan Goodyear

Cancer cells metabolically "fertilize" the tumor microenvironment with hydrogen peroxid... - 0 views

www.ncbi.nlm.nih.gov/...PMC3180189

cancer reverse warburg effect warburg effect NF-kapppB HIF-1alpha Cav-1 H2O2

shared by Nathan Goodyear on 12 Nov 14 - No Cached
  • reducing oxidative stress with powerful antioxidants, is an important strategy for cancer prevention, as it would suppress one of the key early initiating steps where DNA damage and tumor-stroma metabolic-coupling begins. This would prevent cancer cells from acting as metabolic “parasites
  • Oxidative stress in cancer-associated fibroblasts triggers autophagy and mitophagy, resulting in compartmentalized cellular catabolism, loss of mitochondrial function, and the onset of aerobic glycolysis, in the tumor stroma. As such, cancer-associated fibroblasts produce high-energy nutrients (such as lactate and ketones) that fuel mitochondrial biogenesis and oxidative metabolism in cancer cells. We have termed this new energy-transfer mechanism the “reverse Warburg effect.
  • Then, oxidative stress, in cancer-associated fibroblasts, triggers the activation of two main transcription factors, NFκB and HIF-1α, leading to the onset of inflammation, autophagy, mitophagy and aerobic glycolysis in the tumor microenvironment
  • ...38 more annotations...
  • oxidative stress and ROS, produced in cancer-associated fibroblasts, has a “bystander effect” on adjacent cancer cells, leading to DNA damage, genomic instability and aneuploidy, which appears to be driving tumor-stroma co-evolution
  • tumor cells produce and secrete hydrogen peroxide, thereby “fertilizing” the tumor microenvironment and driving the “reverse Warburg effect.”
  • This type of stromal metabolism then produces high-energy nutrients (lactate, ketones and glutamine), as well as recycled chemical building blocks (nucleotides, amino acids, fatty acids), to literally “feed” cancer cells
  • loss of stromal caveolin (Cav-1) is sufficient to drive mitochondrial dysfunction with increased glucose uptake in fibroblasts, mimicking the glycolytic phenotype of cancer-associated fibroblasts.
  • oxidative stress initiated in tumor cells is transferred to cancer-associated fibroblasts.
  • Then, cancer-associated fibroblasts show quantitative reductions in mitochondrial activity and compensatory increases in glucose uptake, as well as high ROS production
  • These findings may explain the prognostic value of a loss of stromal Cav-1 as a marker of a “lethal” tumor microenvironment
  • aerobic glycolysis takes place in cancer-associated fibroblasts, rather than in tumor cells, as previously suspected.
  • our results may also explain the “field effect” in cancer biology,5 as hydrogen peroxide secreted by cancer cells, and the propagation of ROS production, from cancer cells to fibroblasts, would create an increasing “mutagenic field” of ROS production, due to the resulting DNA damage
  • Interruption of this process, by addition of catalase (an enzyme that detoxifies hydrogen peroxide) to the tissue culture media, blocks ROS activity in cancer cells and leads to apoptotic cell death in cancer cells
  • In this new paradigm, cancer cells induce oxidative stress in neighboring cancer-associated fibroblasts
  • cancer-associated fibroblasts have the largest increases in glucose uptake
  • cancer cells secrete hydrogen peroxide, which induces ROS production in cancer-associated fibroblasts
  • Then, oxidative stress in cancer-associated fibroblast leads to decreases in functional mitochondrial activity, and a corresponding increase in glucose uptake, to fuel aerobic glycolysis
  • cancer cells show significant increases in mitochondrial activity, and decreases in glucose uptake
  • fibroblasts and cancer cells in co-culture become metabolically coupled, resulting in the development of a “symbiotic” or “parasitic” relationship.
  • cancer-associated fibroblasts undergo aerobic glycolysis (producing lactate), while cancer cells use oxidative mitochondrial metabolism.
  • We have previously shown that oxidative stress in cancer-associated fibroblasts drives a loss of stromal Cav-1, due to its destruction via autophagy/lysosomal degradation
  • a loss of stromal Cav-1 is sufficient to induce further oxidative stress, DNA damage and autophagy, essentially mimicking pseudo-hypoxia and driving mitochondrial dysfunction
  • loss of stromal Cav-1 is a powerful biomarker for identifying breast cancer patients with early tumor recurrence, lymph-node metastasis, drug-resistance and poor clinical outcome
  • this type of metabolism (aerobic glycolysis and autophagy in the tumor stroma) is characteristic of a lethal tumor micro-environment, as it fuels anabolic growth in cancer cells, via the production of high-energy nutrients (such as lactate, ketones and glutamine) and other chemical building blocks
  • the upstream tumor-initiating event appears to be the secretion of hydrogen peroxide
  • one such enzymatically-active protein anti-oxidant that may be of therapeutic use is catalase, as it detoxifies hydrogen peroxide to water
  • numerous studies show that “catalase therapy” in pre-clinical animal models is indeed sufficient to almost completely block tumor recurrence and metastasis
  • by eliminating oxidative stress in cancer cells and the tumor microenvironment,55 we may be able to effectively cut off the tumor's fuel supply, by blocking stromal autophagy and aerobic glycolysis
  • breast cancer patients show systemic evidence of increased oxidative stress and a decreased anti-oxidant defense, which increases with aging and tumor progression.68–70 Chemotherapy and radiation therapy then promote further oxidative stress.69 Unfortunately, “sub-lethal” doses of oxidative stress during cancer therapy may contribute to tumor recurrence and metastasis, via the activation of myofibroblasts.
  • a loss of stromal Cav-1 is associated with the increased expression of gene profiles associated with normal aging, oxidative stress, DNA damage, HIF1/hypoxia, NFκB/inflammation, glycolysis and mitochondrial dysfunction
  • cancer-associated fibroblasts show the largest increases in glucose uptake, while cancer cells show corresponding decreases in glucose uptake, under identical co-culture conditions
  • Thus, increased PET glucose avidity may actually be a surrogate marker for a loss of stromal Cav-1 in human tumors, allowing the rapid detection of a lethal tumor microenvironment.
  • it appears that astrocytes are actually the cell type responsible for the glucose avidity.
  • In the brain, astrocytes are glycolytic and undergo aerobic glycolysis. Thus, astrocytes take up and metabolically process glucose to lactate.7
  • Then, lactate is secreted via a mono-carboxylate transporter, namely MCT4. As a consequence, neurons use lactate as their preferred energy substrate
  • both astrocytes and cancer-associated fibroblasts express MCT4 (which extrudes lactate) and MCT4 is upregulated by oxidative stress in stromal fibroblasts.34
  • In accordance with the idea that cancer-associated fibroblasts take up the bulk of glucose, PET glucose avidity is also now routinely used to measure the extent of fibrosis in a number of human diseases, including interstitial pulmonary fibrosis, postsurgical scars, keloids, arthritis and a variety of collagen-vascular diseases.
  • PET glucose avidity and elevated serum inflammatory markers both correlate with poor prognosis in breast cancers.
  • PET signal over-estimates the actual anatomical size of the tumor, consistent with the idea that PET glucose avidity is really measuring fibrosis and inflammation in the tumor microenvironment.
  • human breast and lung cancer patients can be positively identified by examining their exhaled breath for the presence of hydrogen peroxide.
  • tumor cell production of hydrogen peroxide drives NFκB-activation in adjacent normal cells in culture6 and during metastasis,103 directly implicating the use of antioxidants, NFκB-inhibitors and anti-inflammatory agents, in the treatment of aggressive human cancers.
  • Nathan Goodyear on 12 Nov 14
     
    Good description of the communication between cancer cells and fibroblasts.  This theory is termed the "reverse Warburg effect".
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