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Nathan Goodyear

Dihydrotestosterone upregulates the expression of epidermal growth factor receptor and ... - 0 views

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    Androgen receptors may be associated with bladder cancer progression.  This study finds AR up regulates Epidermal growth factor in bladder cancer cells.
Nathan Goodyear

Nuclear TK1 expression is an independent prognostic factor for survival in pre-malignan... - 0 views

  • Thymidine kinase 1 (TK1) is a proliferation biomarker
  • Nuclear TK1 expression in early grade CIN predicts risk for progression to malignancy
  • Nuclear TK1 expression is also a prognostic factor for treatment outcome
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  • TK1 LI was found to be a more reliable prognostic marker for 5-year survival than pathological stages, FIGO stages and Ki-67,
  • nuclear TK1 expression is a reliable prognostic factor in CIN patients, a group of cervical lesion patients that respond positively to treatment
  • nuclear TK1 expression is correlated with advanced stage of invasive cervical carcinomas
  • a low TK1 LI can help to identify with a better survival
  • low TK1 expression in the tumors in these patients might indicate that these tumors have a lower proliferation rate
  • TK1 is a key kinase in the one-step salvage pathway by which thymidine is introduced into DNA via the salvage pathway
  • TK1 participates in DNA synthesis and is therefore closely related to the S-phase of the cell cycle, and is correlated with proliferation
  • TK1 intensity (TK1 synthesis rate) increases from CIN grade I to CIN grade III, but does not further increase in invasive cervical carcinomas.
  • TK1 intensity seems to be a prognostic factor particularly when pre-malignant cervical lesions progress to malignancy
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    TK-1 is a proliferation biomarker of DNA repair. TK-1 is a nuclear biomarker of cancer prognosis, survival, recurrence and predicts risk of progression of pre-malignant disease.
Nathan Goodyear

Differential Effects of Dehydroepiandrosterone and Testosterone in Prostate and Colon C... - 0 views

  • Several studies indicate that DHEA may enhance cancer-promoting activities in several prostate cancer cell lines acting as agonist or antagonist for the intracellular AR
  • the estrogenic metabolites of DHEA, 5a-androstane-3b, 17b-diol (3b-Adiol) and E2 bind to estrogen receptors but not to AR
  • no specific receptor has been identified for DHEA
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  • Different members of neurotrophins are expressed during cancer progression, suggesting their involvement in cell proliferation, anoikis protection, and malignancy
  • Regulation of the apoptotic machinery in prostate and colon cancer cells by testosterone occurs rapidly and is initiated at the plasma membrane level through specific membrane-binding sites not involving the classical cytoplasmic AR
  • testosterone exerts potent regulatory effects on prostate and colon cancer cell apoptosis
  • Testosterone increased cell death in a dose-dependent manner
  • testosterone antagonizes the prosurvival effects of DHEA in neuronal cells, blocking its binding to NGF receptors
  • treatment of cells with DHEA exerted a strong antiapoptotic effect,
  • Androgens hold a central role in prostate and colon cancer biology
  • elevated levels of DHEA or its sulfate ester DHEA-sulfate in young adults are associated to low incidence of androgen-dependent tumors
  • DHEA may play a protective role in young prostate
  • The decline of DHEA with aging may contribute to prostate cancer progression associated with advanced age
  • DHEA is an effective antiapoptotic factor, reversing the serum deprivation-induced apoptosis in prostate cancer cells (DU145 and LNCaP cell lines) as well as in colon cancer cells
  • NGF appears to exert similar antiapoptotic actions in both prostate and color cancer cells
  • exposure of prostate DU145 and colon Caco2 cancer cells to testosterone totally blocked the protective effects of both DHEA and NGF. These findings suggest that testosterone acts as an antagonist of DHEA and NGF
  • These findings support the hypothesis that testosterone may inhibit cancer cell growth by antagonizing the proliferative, antiapoptotic effects of endogenous factors, such as DHEA or NGF, in the case of prostate and colon cancer cells
  • intratumor hormonal microenvironment may play a critical role in tumor progression.
  • The paracrine interactions of androgens with locally produced NGF may define tumor cell fate
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    Full article of previously posted abstract.  Cancers are unique.  Not all cancers are alike.  Whether they are tissue specific or not, cancers are unique.  This article describes the uniqueness of DHEA and Testosterone cancer, with particular attention to colon.
Nathan Goodyear

Testosterone level in men with type 2 diabetes mellitus and related metabolic... - 0 views

  • defined by consistent symptoms and signs of androgen deficiency, and an unequivocally low serum testosterone level
  • the threshold serum testosterone level below which adverse clinical outcomes occur in the general population is not known
  • most population-based studies use the serum testosterone level corresponding to the lower limit, quoted from 8.7 to 12.7 nmol/L, of the normal range for young Caucasian men as the threshold
    • Nathan Goodyear
       
      this equals 251 to 366 in serum Total Testosterone
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  • Researchers tried to examine whether serum total or free testosterone would be a better/more reliable choice when studying the effect of testosterone. The results were mixed. Some reported significant associations of both serum total and free testosterone level with clinical parameters25, whereas others reported that only serum free testosterone26 or only serum total testosterone6 showed significant associations.
  • −0.124 nmol/L/year in serum total testosterone
    • Nathan Goodyear
       
      this equates to a 4 ng/dl decline annually in total Testosterone.
  • In experimental studies, androgen receptor knockout mice developed significant insulin resistance rapidly
  • In mouse models, testosterone promoted differentiation of pluripotent stem cells to the myogenic lineage
  • testosterone decreased insulin resistance by enhancing catecholamine induced lipolysis in vitro, and reducing lipoprotein lipase activity and triglyceride uptake in human abdominal tissue in vivo
  • by promoting lipolysis and myogenesis, testosterone might lead to improved insulin resistance
  • testosterone regulated skeletal muscle genes involved in glucose metabolism that led to decreased systemic insulin resistance
  • In the liver, hepatic androgen receptor signaling inhibited development of insulin resistance in mice
  • independent and inverse association of testosterone with hepatic steatosis shown in a cross-sectional study carried out in humans
  • In short, androgen improves insulin resistance by changing body composition and reducing body fat.
  • Although a low serum testosterone level could contribute to the development of obesity and type 2 diabetes through changes in body composition, obesity might also alter the metabolism of testosterone
  • In obese men, the peripheral conversion from testosterone to estrogen could attenuate the amplitude of luteinizing hormone pulses and centrally inhibit testosterone production
  • leptin, an adipokine, has been shown to be inversely correlated with serum testosterone level in men
  • Leydig cells expressed leptin receptors and leptin has been shown to inhibit testosterone secretion, suggesting a role of obesity and leptin in the pathogenesis of low testosterone
    • Nathan Goodyear
       
      So what is "unequivocal"?
  • Baltimore Longitudinal Study of Aging (BLSA) cohort made up of 3,565 middle-class, mostly Caucasian men from the USA, the incidence of low serum total testosterone increased from approximately 20% of men aged over 60 years, 30% over 70 years, to 50% over 80 years-of-age
  • 30–44% sex hormone binding globulin (SHBG)-bound testosterone and 54–68% albumin-bound testosterone
  • As the binding of testosterone to albumin is non-specific and therefore not tight, the sum of free and albumin-bound testosterone is named bioavailable testosterone, which reflects the hormone available at the cellular level
  • Serum total testosterone is composed of 0.5–3.0% of free testosterone unbound to plasma proteins
  • alterations in SHBG concentration might affect total serum testosterone level without altering free or bioavailable testosterone
  • listed in Table​T
  • A significant, independent and longitudinal effect of age on testosterone has been observed with an average change of −0.124 nmol/L/year in serum total testosterone28. The same trend has been shown in Europe and Australia
  • Asian men residing in HK and Japan, but not those living in the USA, had 20% higher serum total testosterone than in Caucasians living in the USA, as shown in a large multinational observational prospective cohort of the Osteoporotic Fractures in Men Study
  • subjects with chronic diseases consistently had a 10–15% lower level compared with age-matched healthy subjects
  • In Caucasians, the mean serum total testosterone level for men in large epidemiological studies has been reported to range from 15.1 to 16.6 nmol/L
  • Asians, higher values, ranging from 18.1 to 19.1 nmol/L, were seen in Korea and Japan
  • Chinese middle-aged men reported a similar mean serum testosterone level of 17.1 nmol/L in 179 men who had a family history of type 2 diabetes and 17.8 nmol/L in 128 men who had no family history of type 2 diabetes
  • The reduction of total testosterone was 0.4% per year in both groups
  • HK involving a cohort of 1,489 community-dwelling men with a mean age of 72 years, a mean serum total testosterone of 19.0 nmol/L was reported
  • pro-inflammatory factors, such as tumor necrosis factor-α in the testes, could locally inhibit testosterone biosynthesis in Leydig cells47, and testosterone treatment in men was shown to reduce the level of tumor necrosis factor-α
  • In Asians, a genetic deletion polymorphism of uridine diphosphate-glucuronosyltransferase UGT2B17 was associated with reduced androgen glucuronidation. This resulted in higher level of active androgen in Asians as compared to Caucasians, as Caucasians' androgen would be glucuronidated into inactive forms faster.
  • Compared with Caucasians, the frequency of this deletion polymorphism of UGT2B17 was 22-fold higher in Asian subjects
  • Other researchers have suggested that environmental, but not genetic, factors influenced serum total testosterone
  • The basal and ligand-induced activity of the AR is inversely associated with the length of the CAG repeat chain
  • In the European Male Aging Study, increased estrogen/androgen ratio in association with longer AR CAG repeat was observed
  • a smaller number of AR CAG repeat had been shown to be associated with benign prostate hypertrophy and faster prostate growth during testosterone treatment
  • In India, men with CAG ≤19 had increased risk of prostate cancer
  • the odds of having a short CAG repeat (≤17) were substantially higher in patients with lymph node-positive prostate cancer than in those with lymph node-negative disease or in the general population
  • assessing the polymorphism at the AR level could be a potential tool towards individualized assessment and treatment of hypogonadism.
  • In elderly men, there was reduced testicular response to gonadotropins with suppressed and altered pulsatility of the hypothalamic pulse generator
  • a significant, independent and longitudinal effect of age on serum total testosterone level had been observed
  • A significant graded inverse association between serum testosterone level and insulin levels independent of age has also been reported in Caucasian men
  • Low testosterone is commonly associated with a high prevalence of MES
  • most studies showed that changes in serum testosterone level led to changes in body composition, insulin resistance and the presence of MES, the reverse might also be possible
  • MES predicted a 2.6-fold increased risk of development of low serum testosterone level independent of age, smoking and other potential confounders
  • Other prospective studies have shown that development of MES accelerated the age-related decline in serum testosterone level
  • In men with type 2 diabetes, changes in serum testosterone level over time correlated inversely with changes in insulin resistance
  • weight loss by either diet control or bariatric surgery led to a substantial increase in total testosterone, especially in morbidly obese men, and the rise in serum testosterone level was proportional to the amount of weight lost
  • To date, published clinical trials are small, of short duration and often used pharmacological, not physiological, doses of testosterone
  • In the population-based Osteoporotic Fractures in Men Study cohort from Sweden, men in the highest quartile of serum testosterone level had the lowest risk of cardiovascular events compared with men in the other three quartiles (hazard ratio [HR] 0.70
  • low serum total testosterone was associated with a significant fourfold higher risk of cardiovascular events when comparing men from the lowest testosterone tertile with those in the highest tertile
  • Shores et al. were the first to report that low serum testosterone level, including both serum total and free testosterone, was associated with increased mortality
  • low serum total testosterone predicted increased risk of cardiovascular mortality with a HR of 1.38
  • low serum total testosterone increased all-cause (HR 1.35, 95% CI 1.13–1.62, P < 0.001) and cardiovascular mortality (HR 1.25
  • European Association for the Study of Diabetes 2013 suggested there was an inverse relationship between serum testosterone level and acute myocardial infarction
  • Diabetic men in the highest quartile of serum total testosterone had a significantly reduced risk of acute MI when compared with those in the lower quartiles
  • serum total testosterone level in the middle two quartiles at baseline predicted reduced incidence of death compared with having the highest and lowest levels
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    Nice review of Testosterone levels and some of the evidence linking Diabetes with low T.  However, the conclusion by the authors regarding what is causing the low T in men with Diabetes is baffling.  The literature does not point to one cause, it is clearly multifactorial--obesity, inflammation, high aromatase activity...I would suggest the authors continue their readings in the manner.
mohsenmotamedian

5 key factors to help lose some good weight with in few days - 0 views

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    As per Max Motamedian, this is where all the extra bloating and water weight can be avoided in the process Also about proteins and fibers as the most helpful factors in any given weight loss regimen.
Nathan Goodyear

Using Multicountry Ecological and Observational Studies to Determine Dietary Risk Facto... - 0 views

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    Western diet appears to be major risk association/factor in Alzheimer's disease risk.
Nathan Goodyear

Effects of dietary polyphenols on neuroregulatory factors and pathways that mediate foo... - 0 views

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    review article of polyphenols positive effect on neuroregulatory factors involved in food intake and energy balance.  Only abstract available here.
Nathan Goodyear

Serum Leptin, Parathyroid Hormone, 1,25-Dihydroxyvitamin D, Fibroblast Growth Factor 23... - 0 views

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    high leptin, high PTH, fibroblastic growth factor, and bone alkaline phosphatase associated with obesity.
Nathan Goodyear

Food intolerance: a major factor in the pathogenesis ... [Lancet. 1982] - PubMed - NCBI - 0 views

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    food intolerance found to be a major factor in IBS.
Nathan Goodyear

Low testosterone level as a predictor of cardiovascular events in Japanese men with cor... - 0 views

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    This study of Japanese men sought to remove CAD risk factors and just look at Testosterone.  In this study, the authors found that low T was associated with increased CAD in Japanese men.
Nathan Goodyear

Male hypogonadism and metabolic syndrome. [Andrologia. 2014] - PubMed - NCBI - 0 views

  • male hypogonadism was an independent risk factor for MS (P < 0.001). We conclude that low testosterone level plays a central role in the development of metabolic syndrome
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    low Testosterone in men was found to be an independent risk factor for metabolic syndrome in men.
Nathan Goodyear

DHA dietary supplementation enhances the effects of exercise on synaptic plasticity and... - 0 views

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    DHA enriched diet plus exercis improved cognition through a increase in brain derived neurotrophic factor (BDNF).  The result was increased neuroplasticity.  Additionally, they were shown to reduce hippocampal lipid peroxidation.
Nathan Goodyear

Acetyl-L-carnitine treatment increases choline ace... [Brain Res. 1994] - PubMed - NCBI - 0 views

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    Rat study, but acetyl-L-carnitine shown to increase nerve growth factor.  In addition, it increased acetylcholine activity.
Nathan Goodyear

Association between endogenous sex steroid hormones and inflammatory biomarkers in US men - 0 views

  • modest statistically significant inverse associations for total and calculated free testosterone, and modest positive associations for total and calculated free estradiol with CRP concentration
  • Estradiol concentrations were also weakly positively associated with WBC count
  • SHBG was weakly inversely associated with WBC
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  • An association between testosterone and WBC count was not observed
  • These findings are consistent with the hypothesis that in men higher androgen concentration is anti-inflammatory, and higher estrogen concentration is pro-inflammatory.
  • the probability of elevated CRP concentrations (≥ 3 mg/L) decreased with higher total and calculated free testosterone concentrations, while the probability increased with higher total and calculated free estradiol concentrations
  • there is ample evidence supporting the immunosuppressive effect of androgens
  • The incidence of autoimmune diseases is higher in androgen-deficient men
  • Studies have shown that the induction of hypogonadism in older men is followed by a significant increase in IL-6 concentrations (Khosla et al. 2002), a potent stimulator of inflammation, and that activation of the androgen receptor exerts a direct anti-inflammatory effect
  • It has been suggested that the mechanisms for the immunosuppressive effect of androgens could be either a direct effect on the expression of inflammatory genes (Bellido et al. 1995; Asirvatham et al. 2006), or an indirect effect through inhibition of nuclear factor-kB activation
  • Estradiol is the major biologically active estrogen, and about 80% is formed in adult men from the aromatization of testosterone primarily in the adipose tissue
  • estrogen can stimulate the transcription factor C/EBP-β, which is involved in CRP transcription
  • Most prior cross-sectional studies have observed inverse associations between androgen concentrations and inflammatory biomarkers
  • A recent study in Chinese men showed that lower concentrations of total and calculated free testosterone were associated with higher CRP concentration
  • Data from the Boston Area Community Health Survey also reported inverse associations between testosterone and CRP concentrations
  • Total testosterone was inversely associated with WBC count (Tang et al. 2007; Schneider et al. 2009; Brand et al. 2012), but calculated free testosterone was not associated with WBC
  • The first trial found a decrease in CRP, interleukin-1β (IL-1β), and tumor necrosis factor-α (TNFα) but no changes in IL-6 and IL-10 concentrations between the active treatment and placebo arms
  • the majority of studies in the literature have not observed statistically significant associations between estradiol and inflammatory biomarkers in men, although several of them observed point estimates in the positive direction
  • total testosterone and estradiol compete for binding to SHBG, and seem to have opposite effects on the concentration of inflammatory biomarkers
  • A small randomized controlled trial of estrogen replacement therapy in prostate cancer patients showed an increase in CRP in the active treatment group versus the comparator group
  • Obese men are known to have lower androgen concentrations compared to their normal-weight counterparts
  • The strongest suggestion of an interaction was the inverse association between androstanediol glucuronide and CRP concentrations in obese participants, while the association was positive in the non-obese
  • A recent Chinese cross-sectional study observed stronger inverse associations between total testosterone and CRP concentrations in individuals with a BMI of 27.5 kg/m2 or greater
  • our results suggest that total and calculated free testosterone are modestly inversely associated with CRP concentrations, and that total and calculated free estradiol are modestly positively associated with CRP and WBC
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    Study results suggest that higher Testosterone and lower Estrogen levels provide anti-inflammatory effects in men.  The inflammatory biomarker assessed here was CRP.  Low total and calculated free Testosterone was associated with an increase in CRP.  In contrast, total and free Estrogen was associated with an increase in CRP.  Estradiol increased WBC count and SHBG was inversely related to WBC count in this study.
Nathan Goodyear

SpringerLink - Abstract - 0 views

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    homocysteine is an independent risk factor for cardiovascular disease
Nathan Goodyear

Plasma Homocysteine as a Risk Factor for Dementia and Alzheimer's Disease - NEJM - 0 views

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    An increased plasma homocysteine level is a strong, independent risk factor for the development of dementia and Alzheimer's disease.
Nathan Goodyear

Neuron - Epigenetic Status of Gdnf in the Ventral Striatum Determines Susceptibility an... - 0 views

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    How you respond to stress is a reflection of your genetics and environment.  The bodies ability to express genes, such as the glial cell-derived neurotrophic factor, impacts an individual's expression in the face of stress.  You have a genetic predisposition, but with poor methylation you end up with more depression in the presence of stress
Nathan Goodyear

ScienceDirect - Trends in Pharmacological Sciences : Pharmacological basis for the role... - 0 views

  • Extensive research within the past two decades has shown that curcumin mediates its anti-inflammatory effects through the downregulation of inflammatory transcription factors (such as nuclear factor κB), enzymes (such as cyclooxygenase 2 and 5 lipoxygenase) and cytokines (such as tumor necrosis factor, interleukin 1 and interleukin 6)
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    curcumin as anti-inflammatory in disease
Nathan Goodyear

Nutrapharmacology of Tocotrienols for Metabol... [Curr Pharm Des. 2011] - PubMed - NCBI - 0 views

  • This review evaluates the effects of tocotrienols on the risk factors of metabolic syndrome using data from human, animal and in vitro studies. Tocotrienols improved lipid profiles and reduced atherosclerotic lesions, decreased blood glucose and glycated hemoglobin concentrations, normalized blood pressure, and inhibited adipogenesis.
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    Tocotrienols, vitamin E, shown to improve metabolic syndrome risk factors.
Nathan Goodyear

Nerve growth factor receptor immunoreactivit... [Mech Ageing Dev. 1993] - PubMed - NCBI - 0 views

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    alpha-GPC appears to increase nerve growth factor receptors in rat brains. 
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