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fitspresso

https://www.fitspresso-co.com/ - 0 views

www.fitspresso-co.com

fitspresso fit spresso us uk buy usa 2023 pros 2022 2024 pills order price weight loss espresso fitespresso review amazon tablet reviews customer supplement does it work

shared by fitspresso on 27 Sep 23 - No Cached
  • fitspresso on 27 Sep 23
     
    FitSpresso™ | Official Site fitspresso-co.com FitSpresso Only $39/Bottle Limited Time Offer! FitSpresso Special Deal + Special 51% Discount Save $660 + 180 Days Money Back Guarantee FitSpresso Herpesyl Five Star A dietary product formulated to assist users in reducing weight can increase other advantages that can support overall health. This product can assist users in getting closer to the desirable body weight. Regular Price: 149/per bottle Only for: $39/per bottle Buy Now What IsFitSpresso? FitSpresso is promoted as a natural supplement that comes in the form of diet pills, and it can aid in rapid and efficient weight loss, similar to many other supplements. The term "natural supplements refers to a nutritional supplement that is made entirely of natural, chemical-free materials. You can utilize these organic ingredients to aid in natural weight loss. It can speed up your body's metabolism and assist with other crucial processes. All parts of our bodies are impacted by weight increase, and not only do we need to deal with the increased weight, but we also need to deal with the numerous problems and illnesses that come along with it. This refers to the risk of developing chronic cardiac conditions, low blood pressure, and, in some circumstances, problems with blood sugar. However, FitSpresso even with its bright and bold claims, can help you efficiently manage your weight and completely avoid these extra uncomfortable problems. FitSpresso is a supplement that comes in the form of a pill, which makes it tasty, simple to swallow, and handy. According to the manufacturer, these diet tablets are GMO-free and toxic-free, making them edible. This is why we have things such as weight loss supplements. Thanks to modern advancements, we can just take a dietary supplement pill to bring about significant weight loss in a completely healthy and natural manner. Not only this, but dietary supplements can also support healthy blood sugar levels and help with
Nathan Goodyear

Lowered testosterone in male obesity: Mechanisms, morbidity and management Tang Fui MN,... - 0 views

www.ajandrology.com/article.asp

Testosterone male obesity overweight men hormone hormones low T Low T

shared by Nathan Goodyear on 15 Jan 14 - No Cached
  • The number of overweight people is expected to increase from 937 million in 2005 to 1.35 billion in 2030
  • Similarly the number of obese people is projected to increase from 396 million in 2005 to 573 million in 2030
  • By 2030, China alone is predicted to have more overweight men and women than the traditional market economies combined
  • ...37 more annotations...
  • diacylglycerol O-acyltransferase 2 (DGAT2), mechanistically implicated in this differential storage, [10] is regulated by dihydrotestosterone, [11] suggesting a potential role for androgens to influence the genetic predisposition to either the MHO or MONW phenotype.
  • bariatric surgery achieves 10%-30% long-term weight loss in controlled studies
  • The fact that obese men have lower testosterone compared to lean men has been recognized for more than 30 years
  • Reductions in testosterone levels correlate with the severity of obesity and men
  • epidemiological data suggest that the single most powerful predictor of low testosterone is obesity, and that obesity is a major contributor of the age-associated decline in testosterone levels.
  • healthy ageing by itself is uncommonly associated with marked reductions in testosterone levels
  • obesity blunts this LH rise, obesity leads to hypothalamic-pituitary suppression irrespective of age which cannot be compensated for by physiological mechanisms
  • Reductions in total testosterone levels are largely a consequence of reductions in sex hormone binding globulin (SHBG) due to obesity-associated hyperinsulinemia
  • although controversial, measurement of free testosterone levels may provide a more accurate assessment of androgen status than the (usually preferred) measurement of total testosterone in situations where SHBG levels are outside the reference range
  • SHBG increases with age
  • marked obesity however is associated with an unequivocal reduction of free testosterone levels, where LH and follicle stimulating hormone (FSH) levels are usually low or inappropriately normal, suggesting that the dominant suppression occurs at the hypothalamic-pituitary level
  • adipose tissue, especially when in the inflamed, insulin-resistant state, expresses aromatase which converts testosterone to estradiol (E 2 ). Adipose E 2 in turn may feedback negatively to decrease pituitary gonadotropin secretion
  • diabetic obesity is associated with decreases in circulatory E 2
  • In addition to E 2 , increased visceral fat also releases increased amounts of pro-inflammatory cytokines, insulin and leptin; all of which may inhibit the activity of the HPT axis at multiple levels
  • In the prospective Massachusetts Male Aging Study (MMAS), moving from a non-obese to an obese state resulted in a decline of testosterone levels
  • weight loss, whether by diet or surgery, increases testosterone levels proportional to the amount of weight lost
  • fat is androgen-responsive
  • low testosterone may augment the effects of a hypercaloric diet
  • In human male ex vivo adipose tissue, testosterone decreased adipocyte differentiation by 50%.
  • Testosterone enhances catecholamine-induced lipolysis in vitro and reduces lipoprotein lipase activity and triglyceride uptake in human abdominal adipose tissue in vivo
  • in men with prostate cancer receiving 12 months of androgen deprivation therapy, fat mass increased by 3.4 kg and abdominal VAT by 22%, with the majority of these changes established within 6 months
  • severe sex steroid deficiency can increase fat mass rapidly
  • bidirectional relationship between testosterone and obesity
  • increasing body fat suppresses the HPT axis by multiple mechanisms [30] via increased secretion of pro-inflammatory cytokines, insulin resistance and diabetes; [19],[44] while on the other hand low testosterone promotes further accumulation of total and visceral fat mass, thereby exacerbating the gonadotropin inhibition
  • androgens may play a more significant role in VAT than SAT
  • men undergoing androgen depletion for prostate cancer show more marked increases in visceral compared to subcutaneous fat following treatment
    • Nathan Goodyear
      Nathan Goodyear on 16 Jan 14
       
      Interesting: low T increases VAT, yet T therapy does not reduce VAT, yet T therapy reduces SAT.
  • irisin, derived from muscle, induces brown fat-like properties in rodent white fat
  • androgens can act via the PPARg-pathway [37] which is implicated in the differentiation of precursor fat cells to the energy-consuming phenotype
  • low testosterone may compound the effect of increasing fat mass by making it more difficult for obese men to lose weight via exercise
  • pro-inflammatory cytokines released by adipose tissue may contribute to loss of muscle mass and function, leading to inactivity and further weight gain in a vicious cycle
  • Sarcopenic obesity, a phenotype recapitulated in men receiving ADT for prostate cancer, [55] may not only be associated with functional limitations, but also aggravate the metabolic risks of obesity;
  • observational evidence associating higher endogenous testosterone with reduced loss of muscle mass and crude measures of muscle function in men losing weight
  • genuine reactivation of the HPT axis in obese men requires more substantial weight-loss
  • A number of intervention studies have confirmed that both diet- and surgically-induced weight losses are associated with increased testosterone, with the rise in testosterone generally proportional to the amount of weight lost
  • men, regardless of obesity level, can benefit from the effect of weight loss.
  • inconsistent effect of testosterone on VAT
  • Nathan Goodyear on 15 Jan 14
     
    to be read
Nathan Goodyear

Testosterone and glucose metabolism in men: current concepts and controversies - 0 views

joe.endocrinology-journals.org/...R37.full

Low T Testosterone metabolic syndrome MetS Diabetes men male glucose hormone hormones g

shared by Nathan Goodyear on 04 Feb 14 - No Cached
  • Around 50% of ageing, obese men presenting to the diabetes clinic have lowered testosterone levels relative to reference ranges based on healthy young men
  • The absence of high-level evidence in this area is illustrated by the Endocrine Society testosterone therapy in men with androgen deficiency clinical practice guidelines (Bhasin et al. 2010), which are appropriate for, but not specific to men with metabolic disorders. All 32 recommendations made in these guidelines are based on either very low or low quality evidence.
  • A key concept relates to making a distinction between replacement and pharmacological testosterone therapy
  • ...59 more annotations...
  • The presence of symptoms was more closely linked to increasing age than to testosterone levels
  • Findings similar to type 2 diabetes were reported for men with the metabolic syndrome, which were associated with reductions in total testosterone of −2.2 nmol/l (95% CI −2.41 to 1.94) and in free testosterone
  • low testosterone is more predictive of the metabolic syndrome in lean men
  • Cross-sectional studies uniformly show that 30–50% of men with type 2 diabetes have lowered circulating testosterone levels, relative to references based on healthy young men
  • In a recent cross-sectional study of 240 middle-aged men (mean age 54 years) with either type 2 diabetes, type 1 diabetes or without diabetes (Ng Tang Fui et al. 2013b), increasing BMI and age were dominant drivers of low total and free testosterone respectively.
  • both diabetes and the metabolic syndrome are associated with a modest reduction in testosterone, in magnitude comparable with the effect of 10 years of ageing
  • In a cross-sectional study of 490 men with type 2 diabetes, there was a strong independent association of low testosterone with anaemia
  • In men, low testosterone is a marker of poor health, and may improve our ability to predict risk
    • Nathan Goodyear
      Nathan Goodyear on 04 Feb 14
       
      probably the most important point made in this article
  • low testosterone identifies men with an adverse metabolic phenotype
  • Diabetic men with low testosterone are significantly more likely to be obese or insulin resistant
  • increased inflammation, evidenced by higher CRP levels
  • Bioavailable but not free testosterone was independently predictive of mortality
  • It remains possible that low testosterone is a consequence of insulin resistance, or simply a biomarker, co-existing because of in-common risk factors.
  • In prospective studies, reviewed in detail elsewhere (Grossmann et al. 2010) the inverse association of low testosterone with metabolic syndrome or diabetes is less consistent for free testosterone compared with total testosterone
  • In a study from the Framingham cohort, SHBG but not testosterone was prospectively and independently associated with incident metabolic syndrome
  • low SHBG (Ding et al. 2009) but not testosterone (Haring et al. 2013) with an increased risk of future diabetes
  • In cross-sectional studies of men with (Grossmann et al. 2008) and without (Bonnet et al. 2013) diabetes, SHBG but not testosterone was inversely associated with worse glycaemic control
  • SHBG may have biological actions beyond serving as a carrier protein for and regulator of circulating sex steroids
  • In men with diabetes, free testosterone, if measured by gold standard equilibrium dialysis (Dhindsa et al. 2004), is reduced
    • Nathan Goodyear
      Nathan Goodyear on 04 Feb 14
       
      expensive, laborious process filled with variables
  • Low free testosterone remains inversely associated with insulin resistance, independent of SHBG (Grossmann et al. 2008). This suggests that the low testosterone–dysglycaemia association is not solely a consequence of low SHBG.
  • Experimental evidence reviewed below suggests that visceral adipose tissue is an important intermediate (rather than a confounder) in the inverse association of testosterone with insulin resistance and metabolic disorders.
  • testosterone promotes the commitment of pluripotent stem cells into the myogenic lineage and inhibits their differentiation into adipocytes
  • testosterone regulates the metabolic functions of mature adipocytes (Xu et al. 1991, Marin et al. 1995) and myocytes (Pitteloud et al. 2005) in ways that reduce insulin resistance.
  • Pre-clinical evidence (reviewed in Rao et al. (2013)) suggests that at the cellular level, testosterone may improve glucose metabolism by modulating the expression of the glucose-transported Glut4 and the insulin receptor, as well as by regulating key enzymes involved in glycolysis.
  • More recently testosterone has been shown to protect murine pancreatic β cells against glucotoxicity-induced apoptosis
  • Interestingly, a reciprocal feedback also appears to exist, given that not only chronic (Cameron et al. 1990, Allan 2013) but also, as shown more recently (Iranmanesh et al. 2012, Caronia et al. 2013), acute hyperglycaemia can lower testosterone levels.
  • There is also evidence that testosterone regulates insulin sensitivity directly and acutely
  • In men with prostate cancer commencing androgen deprivation therapy, both total as well as, although not in all studies (Smith 2004), visceral fat mass increases (Hamilton et al. 2011) within 3 months
  • More prolonged (>12 months) androgen deprivation therapy has been associated with increased risk of diabetes in several large observational registry studies
  • Testosterone has also been shown to reduce the concentration of pro-inflammatory cytokines in some, but not all studies, reviewed recently in Kelly & Jones (2013). It is not know whether this effect is independent of testosterone-induced changes in body composition.
  • the observations discussed in this section suggest that it is the decrease in testosterone that causes insulin resistance and diabetes. One important caveat remains: the strongest evidence that low testosterone is the cause rather than consequence of insulin resistance comes from men with prostate cancer (Grossmann & Zajac 2011a) or biochemical castration, and from mice lacking the androgen receptor.
  • Several large prospective studies have shown that weight gain or development of type 2 diabetes is major drivers of the age-related decline in testosterone levels
  • there is increasing evidence that healthy ageing by itself is generally not associated with marked reductions in testosterone
  • Circulating testosterone, on an average 30%, is lower in obese compared with lean men
  • increased visceral fat is an important component in the association of low testosterone and insulin resistance
  • The vast majority of men with metabolic disorders have functional gonadal axis suppression with modest reductions in testosterone levels
  • obesity is a dominant risk factor
  • men with Klinefelter syndrome have an increased risk of metabolic disorders. Interestingly, greater body fat mass is already present before puberty
  • Only 5% of men with type 2 diabetes have elevated LH levels
  • inhibition of the gonadal axis predominantly takes place in the hypothalamus, especially with more severe obesity
  • Metabolic factors, such as leptin, insulin (via deficiency or resistance) and ghrelin are believed to act at the ventromedial and arcuate nuclei of the hypothalamus to inhibit gonadotropin-releasing hormone (GNRH) secretion from GNRH neurons situated in the preoptic area
  • kisspeptin has emerged as one of the most potent secretagogues of GNRH release
  • hypothesis that obesity-mediated inhibition of kisspeptin signalling contributes to the suppression of the HPT axis, infusion of a bioactive kisspeptin fragment has been recently shown to robustly increase LH pulsatility, LH levels and circulating testosterone in hypotestosteronaemic men with type 2 diabetes
  • A smaller study with a similar experimental design found that acute testosterone withdrawal reduced insulin sensitivity independent of body weight, whereas oestradiol withdrawal had no effects
  • suppression of the diabesity-associated HPT axis is functional, and may hence be reversible
  • Obesity and dysglycaemia and associated comorbidities such as obstructive sleep apnoea (Hoyos et al. 2012b) are important contributors to the suppression of the HPT axis
  • weight gain and development of diabetes accelerate the age-related decline in testosterone
  • Modifiable risk factors such as obesity and co-morbidities are more strongly associated with a decline in circulating testosterone levels than age alone
  • 55% of symptomatic androgen deficiency reverted to a normal testosterone or an asymptomatic state after 8-year follow-up, suggesting that androgen deficiency is not a stable state
  • Weight loss can reactivate the hypothalamic–pituitary–testicular axis
  • Leptin treatment resolves hypogonadism in leptin-deficient men
  • The hypothalamic–pituitary–testicular axis remains responsive to treatment with aromatase inhibitors or selective oestrogen receptor modulators in obese men
  • Kisspeptin treatment increases LH secretion, pulse frequency and circulating testosterone levels in hypotestosteronaemic men with type 2 diabetes
  • change in BMI was associated with the change in testosterone (Corona et al. 2013a,b).
  • weight loss can lead to genuine reactivation of the gonadal axis by reversal of obesity-associated hypothalamic suppression
  • There is pre-clinical and observational evidence that chronic hyperglycaemia can inhibit the HPT axis
  • in men who improved their glycaemic control over time, testosterone levels increased. By contrast, in those men in whom glycaemic control worsened, testosterone decreased
  • testosterone levels should be measured after successful weight loss to identify men with an insufficient rise in their testosterone levels. Such men may have HPT axis pathology unrelated to their obesity, which will require appropriate evaluation and management.
  • Nathan Goodyear on 04 Feb 14
     
    Article discusses the expanding evidence of low T and Metabolic syndrome.
Nathan Goodyear

Metabolic endotoxemia: a molecular link between obesity and cardiovascular risk - 0 views

jme.endocrinology-journals.org/...R51.full

metabolic endotoxemia obesity insulin resistance cardiovascular disease LPS inflammation

shared by Nathan Goodyear on 04 Aug 14 - No Cached
  • Weight gain has been associated with a higher gut permeability
  • a high-fat diet promotes LPS absorption
  • higher concentrations of fatty acids impair intestinal barrier integrity
  • ...37 more annotations...
  • The starting point for innate immunity activation is the recognition of conserved structures of bacteria, viruses, and fungal components through pattern-recognition receptors
  • TLRs are PRRs that recognize microbe-associated molecular patterns
  • TLRs are transmembrane proteins containing extracellular domains rich in leucine repeat sequences and a cytosolic domain homologous to the IL1 receptor intracellular domain
  • The major proinflammatory mediators produced by the TLR4 activation in response to endotoxin (LPS) are TNFα, IL1β and IL6, which are also elevated in obese and insulin-resistant patients
  • Obesity, high-fat diet, diabetes, and NAFLD are associated with higher gut permeability leading to metabolic endotoxemia.
  • Probiotics, prebiotics, and antibiotic treatment can reduce LPS absorption
  • LPS promotes hepatic insulin resistance, hypertriglyceridemia, hepatic triglyceride accumulation, and secretion of pro-inflammatory cytokines promoting the progression of fatty liver disease.
  • In the endothelium, LPS induces the expression of pro-inflammatory, chemotactic, and adhesion molecules, which promotes atherosclerosis development and progression.
  • In the adipose tissue, LPS induces adipogenesis, insulin resistance, macrophage infiltration, oxidative stress, and release of pro-inflammatory cytokines and chemokines.
  • the gut microbiota has been recently proposed to be an environmental factor involved in the control of body weight and energy homeostasis by modulating plasma LPS levels
  • dietary fats alone might not be sufficient to cause overweight and obesity, suggesting that a bacterially related factor might be responsible for high-fat diet-induced obesity.
  • This was accompanied in high-fat-fed mice by a change in gut microbiota composition, with reduction in Bifidobacterium and Eubacterium spp.
  • n humans, it was also shown that meals with high-fat and high-carbohydrate content (fast-food style western diet) were able to decrease bifidobacteria levels and increase intestinal permeability and LPS concentrations
  • it was demonstrated that, more than the fat amount, its composition was a critical modulator of ME (Laugerette et al. 2012). Very recently, Mani et al. (2013) demonstrated that LPS concentration was increased by a meal rich in saturated fatty acids (SFA), while decreased after a meal rich in n-3 polyunsaturated fatty acids (n-3 PUFA).
  • this effect seems to be due to the fact that some SFA (e.g., lauric and mystiric acids) are part of the lipid-A component of LPS and also to n-3 PUFA's role on reducing LPS potency when substituting SFA in lipid-A
  • these experimental results suggest a pivotal role of CD14-mediated TLR4 activation in the development of LPS-mediated nutritional changes.
  • This suggests a link between gut microbiota, western diet, and obesity and indicates that gut microbiota manipulation can beneficially affect the host's weight and adiposity.
  • endotoxemia was independently associated with energy intake but not fat intake in a multivariate analysis
  • in vitro that endotoxemia activates pro-inflammatory cytokine/chemokine production via NFκB and MAPK signaling in preadipocytes and decreased peroxisome proliferator-activated receptor γ activity and insulin responsiveness in adipocytes.
  • T2DM patients have mean values of LPS that are 76% higher than healthy controls
  • LPS-induced release of glucagon, GH and cortisol, which inhibit glucose uptake, both peripheral and hepatic
  • LPSs also seem to induce ROS-mediated apoptosis in pancreatic cells
  • Recent evidence has been linking ME with dyslipidemia, increased intrahepatic triglycerides, development, and progression of alcoholic and nonalcoholic fatty liver disease
  • The hepatocytes, rather than hepatic macrophages, are the cells responsible for its clearance, being ultimately excreted in bile
  • All the subclasses of plasma lipoproteins can bind and neutralize the toxic effects of LPS, both in vitro (Eichbaum et al. 1991) and in vivo (Harris et al. 1990), and this phenomenon seems to be dependent on the number of phospholipids in the lipoprotein surface (Levels et al. 2001). LDL seems to be involved in LPS clearance, but this antiatherogenic effect is outweighed by its proatherogenic features
  • LPS produces hypertriglyceridemia by several mechanisms, depending on LPS concentration. In animal models, low-dose LPS increases hepatic lipoprotein (such as VLDL) synthesis, whereas high-dose LPS decreases lipoprotein catabolism
  • When a dose of LPS similar to that observed in ME was infused in humans, a 2.5-fold increase in endothelial lipase was observed, with consequent reduction in total and HDL. This mechanism may explain low HDL levels in ‘ME’ and other inflammatory conditions such as obesity and metabolic syndrome
  • It is known that the high-fat diet and the ‘ME’ increase intrahepatic triglyceride accumulation, thus synergistically contributing to the development and progression of alcoholic and NAFLD, from the initial stages characterized by intrahepatic triglyceride accumulation up to chronic inflammation (nonalcoholic steatohepatitis), fibrosis, and cirrhosis
  • On the other hand, LPS activates Kupffer cells leading to an increased production of ROS and pro-inflammatory cytokines like TNFα
  • high-fat diet mice presented with ME, which positively and significantly correlated with plasminogen activator inhibitor (PAI-1), IL1, TNFα, STAMP2, NADPHox, MCP-1, and F4/80 (a specific marker of mature macrophages) mRNAs
  • prebiotic administration reduces intestinal permeability to LPS in obese mice and is associated with decreased systemic inflammation when compared with controls
  • Cani et al. also found that high-fat diet mice presented with not only ME but also higher levels of inflammatory markers, oxidative stress, and macrophage infiltration markers
  • This suggests that important links between gut microbiota, ME, inflammation, and oxidative stress are implicated in a high-fat diet situation
  • high-fat feeding is associated with adipose tissue macrophage infiltration (F4/80-positive cells) and increased levels of chemokine MCP-1, suggesting a strong link between ME, proinflammatory status, oxidative stress, and, lately, increased CV risk
  • LPS has been shown to promote atherosclerosis
  • markers of systemic inflammation such as circulating bacterial endotoxin were elevated in patients with chronic infections and were strong predictors of increased atherosclerotic risk
  • As a TLR4 ligand, LPS has been suggested to induce atherosclerosis development and progression, via a TLR4-mediated inflammatory state.
  • Nathan Goodyear on 04 Aug 14
     
    Very nice updated review on Metabolic endotoxemia
Nathan Goodyear

Divergent trends in obesity and fat intake patterns... [Am J Med. 1997] - PubMed - NCBI - 0 views

www.ncbi.nlm.nih.gov/...9217594

obesity trends fat intake low fat diet' low fat diet

shared by Nathan Goodyear on 02 May 13 - No Cached
  • Nathan Goodyear on 02 May 13
     
    Fat intake is inversely associated with the obesity trend.  During, the 80's, a low fat diet was all the craze.  However, the obesity trend increased with the incorporation of the the low fat diet in America.
Nathan Goodyear

Diet-induced obesity and low testosterone increase neuroinflammation and impair neural ... - 0 views

www.ncbi.nlm.nih.gov/...PMC4190446

Testosterone neuroinflammation glia insulin resistance obesity diabetes brain CNS PNS inflammation low T low Testosterone TNF-alpha IL-1beta

shared by Nathan Goodyear on 28 Apr 15 - No Cached
  • both obesity and low testosterone are also risk factors for neural dysfunction, including cognitive impairment [58–61] and development of AD
  • Levels of obesity and testosterone are often inversely correlated
  • diet-induced obesity causes significant metabolic disturbances and impairs central and peripheral nervous systems.
  • ...23 more annotations...
  • both obesity and low testosterone are linked with promotion of inflammatory pathways [70–72] and exert harmful actions on the central [73–75] and peripheral [29,76] nervous systems
  • In general, obesity-related changes were worsened by low testosterone and improved by testosterone treatment; however, this relationship was not statistically significant in several instances. Further, our data suggest that a common pathway that may contribute to obesity and testosterone effects is regulation of inflammation
  • fasting blood glucose levels were independently and additively increased by GDX-induced testosterone depletion and high-fat diet
  • testosterone treatment significantly reduced fasting glucose under both the normal and high-fat diets, demonstrating potential therapeutic efficacy of testosterone supplementation
  • fasting insulin, insulin resistance (HOMA index), and glucose tolerance, low testosterone tended to exacerbate and or testosterone treatment improved outcomes.
  • testosterone status did not significantly affect body weight
  • testosterone’s effects likely do not indicate an indirect result on adiposity but rather regulatory action(s) on other aspects of metabolic homeostasis
  • Prior work in rodents has shown diet-induced obesity induces insulin resistance in rat brain [63] and that testosterone replacement improves insulin sensitivity in obese rats [64]. Our findings are consistent with the human literature, which indicates that (i) testosterone levels are inversely correlated to insulin resistance and T2D in healthy [30,65] as well as obese men [66], and (ii) androgen therapy can improve some metabolic measures in overweight men with low testosterone
  • it has been shown that TNFα has inhibitory effects on neuron survival, differentiation, and neurite outgrowth
  • Our data demonstrate that low testosterone and obesity independently increased cerebrocortical mRNA levels of both TNFα and IL-1β
  • Testosterone status also affected metabolic and neural measures
  • many beneficial effects of testosterone, including inhibition of proinflammatory cytokine expression
  • neuroprotection [80,81], are dependent upon androgen receptors, the observed effects of testosterone in this study may involve androgen receptor activation
  • testosterone can be converted by the enzyme aromatase into estradiol, which is also known to exert anti-inflammatory [82] and neuroprotective [83] actions
  • glia are the primary sources of proinflammatory molecules in the CNS
  • poorer survival of neurons grown on glia from mice maintained on high-fat diet
  • Since testosterone can affect glial function [86] and improve neuronal growth and survival [87–89], it was unexpected that testosterone status exhibited rather modest effects on neural health indices with the only significant response being an increase in survival in the testosterone-treated, high-fat diet group
  • significantly increased expression of TNFα and IL-1β in glia cultures derived from obese mice
  • testosterone treatment significantly lowered TNFα and IL-1β expression to near basal levels even in obese mice, indicating a protective benefit of testosterone across diet conditions
  • IL-1β treatment has been shown to induce synapse loss and inhibit differentiation of neurons
  • Testosterone status and diet-induced obesity were associated with significant regulation of macrophage infiltration
  • testosterone prevented and/or restored thermal nociception in both diet groups
  • a possible mechanism by which obesity and testosterone levels may affect the health of both CNS and PNS
  • Nathan Goodyear on 28 Apr 15
     
    Study points to obesity and low Testosterone contribution of neuroinflammation.  No effect of body weight was seen with TRT.  This animal model found similar positive effects of TRT in insulin sensitivity.  Obesity and low T increase inflammatory cytokine production: this study found an increase in TNF-alpha and IL-1beta and TRT reduced TNF-alpha and IL-1beta to near base-line.  Testosterone is neuroprotective and this study reviewed the small volume of evaded that pointed to benefit from estradiol.  Testosterone's effect on glial survival was positive but not significant.  Obesity and low T were found to be associated with increased macrophage infiltration in the PNS with increased TNF-alpha and IL-1beta.   Testosterone therapy improved peripheral neuropathy via its positive effects on nocicieption.
Nathan Goodyear

Fat-free mass index and fat mass index percentiles in Caucasians aged 1898 y - 0 views

www.nature.com/...0802037a.html

FMI FFMI body composition BMI fat mass index

shared by Nathan Goodyear on 27 Jul 16 - No Cached
  • BMI is the sum of FFMI+FMI
  • FMI were significantly higher in elderly subjects as compared to younger ones
  • During menopause and aging39,40 changes in FFM and FM are not adequately picked up by changes in BMI
  • ...8 more annotations...
  • One advantage of FMI, as compared to the BMI concept, is that it amplifies the relative effect of aging on body fat
  • We believe that the definition of obesity based on relative body fat (ie percentage) remains of great value for the definition of obesity. However, in a situation in which a patient is losing weight without substantially changing his/her relative body fat (as is the case with crash diets), the calculation of FMI will quantitatively reveal the amount of body fat store lost.
  • high sensitivity of FMI (respectively FFMI) to a slight change of body fat stores
  • Sarcopenic obesity has been defined as a low FFM associated with a high body fat
  • relative FFM lower than 73% (ie a relative body fat greater than 27%) in men and a FFM lower than 62% (ie a body fat greater than 38%) in women.
  • FMIs greater than 8.2 kg/m2 in men and 11.8 kg/m2 in women would define the 'overfat' status (rather than the overweight range) in terms of fat mass
  • In young women, FMI averaged 5.5 kg/m2 (range 5th-95th percentile: 3.5-8.7 kg/m2) ie 38% higher than in males
  • the average FMI for young men was 4.0 kg/m2
  • Nathan Goodyear on 27 Jul 16
     
    good review of FMI, FFMI, and BMI.
Nathan Goodyear

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

www.ncbi.nlm.nih.gov/...PMC4364844

low T low Testosterone Diabetes Testosterone men male hormones metabolic syndrome

shared by Nathan Goodyear on 30 Mar 15 - No Cached
  • 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
      Nathan Goodyear on 31 Mar 15
       
      this equals 251 to 366 in serum Total Testosterone
  • ...57 more annotations...
  • 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
      Nathan Goodyear on 31 Mar 15
       
      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
      Nathan Goodyear on 31 Mar 15
       
      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
  • Nathan Goodyear on 30 Mar 15
     
    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.
Nathan Goodyear

Cell Metabolism - Orexin Is Required for Brown Adipose Tissue Development, Differentiat... - 0 views

www.cell.com/...S1550-4131(11)00340-8

orexin brown-fat weight-loss overweight obesity brown fat

shared by Nathan Goodyear on 01 Dec 11 - No Cached
  • Nathan Goodyear on 01 Dec 11
     
    orexin plays a role in weight gain through regulation of brown fat differentiation.  Low brown fat predisposes one to obesity.  Higher brown fat increases metabolism and thus increases fat burning capacity
Nathan Goodyear

A Lower-Carbohydrate, Higher-Fat Diet Reduces Abdominal and Intermuscular Fat and Incre... - 0 views

jn.nutrition.org/...177S.abstract

nutrition diet high fat diet low carb diet fats carbohydrates weight fat fat mass insulin resistance obesity diabetes TNF-alpha insulin sensitivity

shared by Nathan Goodyear on 23 Mar 15 - No Cached
  • Nathan Goodyear on 23 Mar 15
     
    Diet higher in fats and lower in carbs associated with a reduction in weight, fat mass, improved insulin sensitivity, lowered fasting glucose, and a reduction in TNF-alpha
Nathan Goodyear

JAMA Network | JAMA: The Journal of the American Medical Association | Low-Fat Dietary ... - 0 views

jama.jamanetwork.com/article.aspx

low fat diet colorectal cancer cancer women dietary

shared by Nathan Goodyear on 13 Jun 12 - No Cached
  • Nathan Goodyear on 13 Jun 12
     
    The women's health initiative dietary modification trial of almost 50,000 women found no association between a low fat diet and a reduction of colorectal cancer.  Translation: a low fat diet does not lower the risk of colorectal cancer.
Nathan Goodyear

Testosterone Deficiency, Cardiac Health, and Older Men - 0 views

www.hindawi.com/...143763

low T Testosterone obesity type II diabetes diabetes health wellness metabolic syndrome lipids cholesterol hypogonadism TDS testicular dysgenesis syndrome men male hormone hormones prostate cancer

shared by Nathan Goodyear on 12 May 14 - No Cached
  • Studies have shown pharmacological doses of testosterone to relax coronary arteries when injected intraluminally [39] and to produce modest but consistent improvement in exercise-induced angina and reverse associated ECG changes [40]. The mechanism of action is via blockade of calcium channels with effect of similar magnitude to nifedipine
    • Nathan Goodyear
      Nathan Goodyear on 12 May 14
       
      This directly refutes the recent studies (3) that Testosterone therapy increases cardiovascular events.
    • Nathan Goodyear
      Nathan Goodyear on 13 May 14
       
      Testosterone acts as a calcium channel blocker inducing vasodilation.
  • men with chronic stable angina pectoris, the ischaemic threshold increased after 4 weeks of TRT and a recent study demonstrates improvement continuing beyond 12 months [
  • Exercise capacity in men with chronic heart failure increased after 12 weeks
  • ...36 more annotations...
  • Studies have shown an inverse relationship between serum testosterone and fasting blood glucose and insulin levels
  • Medications such as chronic analgesics, anticonvulsants, 5ARIs, and androgen ablation therapy are associated with increased risk of testosterone deficiency and insulin resistance
  • Women with T2D or metabolic syndrome characteristically have low SHBG and high free testosterone
    • Nathan Goodyear
      Nathan Goodyear on 12 May 14
       
      This stands in polar opposite of that with men.
  • Hypogonadism is a common feature of the metabolic syndrome
  • The precise interaction between insulin resistance, visceral adiposity, and hypogonadism is, as yet, unclear but the important mechanisms are through increased aromatase production, raised leptin levels, and increase in inflammatory kinins
  • levels of testosterone are reduced in proportion to degree of obesity
  • Men should be encouraged to combine aerobic exercise with strength training. As muscle increases, glucose will be burned more efficiently and insulin levels will fall. A minimum of 30 minutes exercise three times weekly should be advised
  • Testosterone increases levels of fast-twitch muscle fibres
  • By increasing testosterone, levels of type 2 fibres increase and glucose burning improves
  • Weight loss will increase levels of testosterone
  • studies now clearly show that low testosterone leads to visceral obesity and metabolic syndrome and is also a consequence of obesity
  • In the case of MMAS [43], a baseline total testosterone of less than 10.4 nmol/L was associated with a greater than 4-fold incidence of type 2 diabetes over the next 9 years
  • There is high level evidence that TRT improves insulin resistance
  • Low testosterone predicts increased mortality and testosterone therapy improves survival in 587 men with type 2 diabetes
  • A similar retrospective US study involved 1031 men with 372 on TRT. The cumulative mortality was 21% in the untreated group versus 10% ( ) in the treated group with the greatest effect in younger men and those with type 2 diabetes
  • the presence of ED has been shown to be an independent risk factor, particularly in hypogonadal men, increasing the risk of cardiac events by over 50%
  • A recent online publication on ischaemic heart disease mortality in men concluded optimal androgen levels are a biomarker for survival
  • inverse associations between low TT or FT (Table 2) and the severity of CAD
  • A recent 10 year study from Western Australia involving 3690 men followed up from 2001–2010 concluded that TT and FT levels in the normal range were associated with decreased all-cause and cardiovascular mortality, for the first time suggesting that both low and DHT are associated with all-cause mortality and higher levels of DHT reduced cardiovascular risk
  • TDS is associated with increased cardiovascular and all-cause mortality
  • The effect of treatment with TRT reduced the mortality rate of treated cohort (8.4%) to that of the eugonadal group whereas the mortality for the untreated remained high at 19.2%
  • hypogonadal men had slightly increased triglycerides and HDL
  • Men with angiographically proven CAD (coronary artery disease) have significantly lower testosterone levels [29] compared to controls ( ) and there was a significant inverse relationship between the degree of CAD and TT (total testosterone) levels
  • TRT has also been shown to reduce fibrinogen to levels similar to fibrates
  • men treated with long acting testosterone showed highly significant reductions in TC, LDL, and triglycerides with increase in HDL, associated with significant reduction in weight, BMI, and visceral fat
  • Low androgen levels are associated with an increase in inflammatory markers
  • In the Moscow study, C-reactive protein was reduced by TRT at 30 weeks versus placebo
  • In some studies, a decline in diastolic blood pressure has been observed, after 3–9 months [24, 26] and in systolic blood pressure
  • A decline was noted in IL6 and TNF-alpha
  • No studies to date show an increase in LUTS/BPH symptoms with higher serum testosterone levels
  • TRT has been shown to upregulate PDE5 [65] and enhance the effect of PDE5Is (now an accepted therapy for both ED and LUTS), it no longer seems logical to advice avoidance of TRT in men with mild to moderate BPH.
    • Nathan Goodyear
      Nathan Goodyear on 12 May 14
       
      What about just starting with normalization of Testosterone levels first.
  • Several meta-analyses have failed to show a link between TRT and development of prostate cancer [66] but some studies have shown a tendency for more aggressive prostate cancer in men with low testosterone
    • Nathan Goodyear
      Nathan Goodyear on 12 May 14
       
      And if one would have looked at their estrogen levels, I guarantee they would have been found to be elevated.
  • low bioavailable testosterone and high SHBG were associated with a 4.9- and 3.2-fold risk of positive biopsy
  • Current EAU, ISSAM, and BSSM guidance [1, 2] is that there is “no evidence TRT is associated with increased risk of prostate cancer or activation of subclinical cancer.”
  • Men with prostate cancer, treated with androgen deprivation, develop an increase of fat mass with an altered lipid profile
  • Erectile dysfunction is an established marker for future cardiovascular risk and the major presenting symptom leading to a diagnosis of low testosterone
Nathan Goodyear

Low-fat diets and testosterone in men: Systematic review and meta-analysis of intervent... - 0 views

www.sciencedirect.com/...S0960076021000716

nutrition Testosterone androgens diet low-fat fat

shared by Nathan Goodyear on 07 Jun 21 - No Cached
  • Nathan Goodyear on 07 Jun 21
     
    Low fat diet lowers androgens more that high fat diet in this meta-analysis.
  • tolariz on 16 Aug 21
     
    What do you think about this topical Androgel 50mg (https://tolariz.com/androgel-50mg/) ? Is it really effective for transgender women to men?
Nathan Goodyear

Testosterone: a metabolic hormone in health and disease - 0 views

joe.endocrinology-journals.org/...R25.full

male hormone hormones testosterone hypogonadal-obesity-adipocytokine hypothesis

shared by Nathan Goodyear on 08 May 13 - No Cached
  • E2 and the inflammatory adipocytokines tumour necrosis factor α (TNFα) and interleukin 6 (IL6) inhibit hypothalamic production of GNRH and subsequent release of LH and FSH from the pituitary
  • Leptin, an adipose-derived hormone with a well-known role in regulation of body weight and food intake, also induces LH release under normal conditions via stimulation of hypothalamic GNRH neurons
  • In human obesity, whereby adipocytes are producing elevated amounts of leptin, the hypothalamic–pituitary axis becomes leptin resistant
  • ...39 more annotations...
  • there is evidence from animal studies that leptin resistance, inflammation and oestrogens inhibit neuronal release of kisspeptin
  • Beyond hypothalamic action, leptin also directly inhibits the stimulatory action of gonadotrophins on the Leydig cells of the testis to decrease testosterone production; therefore, elevated leptin levels in obesity may further diminish androgen status
  • Prostate cancer patients with pre-existing T2DM show a further deterioration of insulin resistance and worsening of diabetic control following ADT
  • ADT for the treatment of prostatic carcinoma in some large epidemiological studies has been shown to be associated with an increased risk of developing MetS and T2DM
  • Non-diabetic men undergoing androgen ablation show increased occurrence of new-onset diabetes and demonstrate elevated insulin levels and worsening glycaemic control
  • increasing insulin resistance assessed by glucose tolerence test and hypoglycemic clamp was shown to be associated with a decrease in Leydig cell testosterone secretion in men
  • The response to testosterone replacement of insulin sensitivity is in part dependent on the androgen receptor (AR)
  • Low levels of testosterone have been associated with an atherogenic lipoprotein profile, characterised by high LDL and triglyceride levels
  • a positive correlation between serum testosterone and HDL has been reported in both healthy and diabetic men
  • up to 70% of the body's insulin sensitivity is accounted for by muscle
  • Testosterone deficiency is associated with a decrease in lean body mass
  • relative muscle mass is inversely associated with insulin resistance and pre-diabetes
  • GLUT4 and IRS1 were up-regulated in cultured adipocytes and skeletal muscle cells following testosterone treatment at low dose and short-time incubations
  • local conversion of testosterone to DHT and activation of AR may be important for glucose uptake
  • inverse correlation between testosterone levels and adverse mitochondrial function
  • orchidectomy of male Wistar rats and associated testosterone deficiency induced increased absorption of glucose from the intestine
  • (Kelley & Mandarino 2000). Frederiksen et al. (2012a) recently demonstrated that testosterone may influence components of metabolic flexibility as 6 months of transdermal testosterone treatment in aging men with low–normal bioavailable testosterone levels increased lipid oxidation and decreased glucose oxidation during the fasting state.
  • Decreased lipid oxidation coupled with diet-induced chronic FA elevation is linked to increased accumulation of myocellular lipid, in particular diacylglycerol and/or ceramide in myocytes
  • In the Chang human adult liver cell line, insulin receptor mRNA expression was significantly increased following exposure to testosterone
  • Testosterone deprivation via castration of male rats led to decreased expression of Glut4 in liver tissue, as well as adipose and muscle
  • oestrogen was found to increase the expression of insulin receptors in insulin-resistant HepG2 human liver cell line
  • FFA decrease hepatic insulin binding and extraction, increase hepatic gluconeogenesis and increase hepatic insulin resistance.
  • Only one, albeit large-scale, population-based cross-sectional study reports an association between low serum testosterone concentrations and hepatic steatosis in men (Völzke et al. 2010)
  • This suggests that testosterone may confer some of its beneficial effects on hepatic lipid metabolism via conversion to E2 and subsequent activation of ERα.
  • hypogonadal men exhibiting a reduced lean body mass and an increased fat mass, abdominal or central obesity
  • visceral adipose tissue was inversely correlated with bioavailable testosterone
  • there was no change in visceral fat mass in aged men with low testosterone levels following 6 months of transdermal TRT, yet subcutaneous fat mass was significantly reduced in both the thigh and the abdominal areas when analysed by MRI (Frederiksen et al. 2012b)
  • ADT of prostate cancer patients increased both visceral and subcutaneous abdominal fat in a 12-month prospective observational study (Hamilton et al. 2011)
  • Catecholamines are the major lipolysis regulating hormones in man and regulate adipocyte lipolysis through activation of adenylate cyclase to produce cAMP
  • deficiency of androgen action decreases lipolysis and is primarily responsible for the induction of obesity (Yanase et al. 2008)
  • may be some regional differences in the action of testosterone on subcutaneous and visceral adipose function
  • proinflammatory adipocytokines IL1, IL6 and TNFα are increased in obesity with a downstream effect that stimulates liver production of CRP
  • observational evidence suggests that IL1β, IL6, TNFα and CRP are inversely associated with serum testosterone levels in patients
  • TRT has been reported to significantly reduce these proinflammatory mediators
  • This suggests a role for AR in the metabolic actions of testosterone on fat accumulation and adipose tissue inflammatory response
  • testosterone treatment may have beneficial effects on preventing the pathogenesis of obesity by inhibiting adipogenesis, decreasing triglyceride uptake and storage, increasing lipolysis, influencing lipoprotein content and function and may directly reduce fat mass and increase muscle mass
  • Early interventional studies suggest that TRT in hypogonadal men with T2DM and/or MetS has beneficial effects on lipids, adiposity and parameters of insulin sensitivity and glucose control
  • Evidence that whole-body insulin sensitivity is reduced in testosterone deficiency and increases with testosterone replacement supports a key role of this hormone in glucose and lipid metabolism
  • Impaired insulin sensitivity in these three tissues is characterised by defects in insulin-stimulated glucose transport activity, in particular into skeletal muscle, impaired insulin-mediated inhibition of hepatic glucose production and stimulation of glycogen synthesis in liver, and a reduced ability of insulin to inhibit lipolysis in adipose tissue
  • Nathan Goodyear on 08 May 13
     
    Great review of the Hypogonadal-obesity-adipocytokine hypothesis.
Nathan Goodyear

Testosterone and glucose metabolism in men: current concepts and controversies - 0 views

joe.endocrinology-journals.org/...R37.full

shared by Nathan Goodyear on 04 Feb 14 - No Cached
    • Nathan Goodyear
      Nathan Goodyear on 04 Feb 14
       
      80% of E2 production in men, that will cause low T in men, comes from SQ adiposity.  This leads to increase in visceral adiposity.
  • Only 5% of men with type 2 diabetes have elevated LH levels (Dhindsa et al. 2004, 2011). This is consistent with recent findings that the inhibition of the gonadal axis predominantly takes place in the hypothalamus, especially with more severe obesity
  • Metabolic factors, such as leptin, insulin (via deficiency or resistance) and ghrelin are believed to act at the ventromedial and arcuate nuclei of the hypothalamus to inhibit gonadotropin-releasing hormone (GNRH) secretion
  • ...32 more annotations...
  • kisspeptin has emerged as one of the most potent secretagogues of GNRH release
  • Consistent with the hypothesis that obesity-mediated inhibition of kisspeptin signalling contributes to the suppression of the HPT axis, infusion of a bioactive kisspeptin fragment has been recently shown to robustly increase LH pulsatility, LH levels and circulating testosterone in hypotestosteronaemic men with type 2 diabetes
  • Figure 4
  • Interestingly, a recent 16-week study of experimentally induced hypogonadism in healthy men with graded testosterone add-back either with or without concomitant aromatase inhibitor treatment has in fact suggested that low oestradiol (but not low testosterone) may be responsible for the hypogonadism-associated increase in total body and intra-abdominal fat mass
    • Nathan Goodyear
      Nathan Goodyear on 04 Feb 14
       
      This does not fit with the research on receptors, specifically estrogen receptors.  These studies that the authors are referencing are looking at "circulating" levels, not tissue levels.
  • A smaller study with a similar experimental design found that acute testosterone withdrawal reduced insulin sensitivity independent of body weight, whereas oestradiol withdrawal had no effects
  • Obesity and dysglycaemia and associated comorbidities such as obstructive sleep apnoea (Hoyos et al. 2012b) are important contributors to the suppression of the HPT axis
  • This is supported by observational studies showing that weight gain and development of diabetes accelerate the age-related decline in testosterone
  • Weight loss can reactivate the hypothalamic–pituitary–testicular axis
  • The hypothalamic–pituitary–testicular axis remains responsive to treatment with aromatase inhibitors or selective oestrogen receptor modulators in obese men
  • Kisspeptin treatment increases LH secretion, pulse frequency and circulating testosterone levels in hypotestosteronaemic men with type 2 diabetes
  • Several observational and randomised studies reviewed in Grossmann (2011) have shown that weight loss, whether by diet or surgery, leads to substantial increases in testosterone, especially in morbidly obese men
  • This suggests that weight loss can lead to genuine reactivation of the gonadal axis by reversal of obesity-associated hypothalamic suppression
  • There is pre-clinical and observational evidence that chronic hyperglycaemia can inhibit the HPT axis
  • in those men in whom glycaemic control worsened, testosterone decreased
  • successful weight loss combined with optimisation of glycaemic control may be sufficient to normalise circulating testosterone levels in the majority of such men
  • weight loss, optimisation of diabetic control and assiduous care of comorbidities should remain the first-line approach.
    • Nathan Goodyear
      Nathan Goodyear on 04 Feb 14
       
      This obviously goes against marketing-based medicine
  • In part, the discrepant results may be due to the fact men in the Vigen cohort (Vigen et al. 2013) had a higher burden of comorbidities. Given that one (Basaria et al. 2010), but not all (Srinivas-Shankar et al. 2010), RCTs in men with a similarly high burden of comorbidities reported an increase in cardiovascular events in men randomised to testosterone treatment (see section on Testosterone therapy: potential risks below) (Basaria et al. 2010), testosterone should be used with caution in frail men with multiple comorbidities
  • The retrospective, non-randomised and non-blinded design of these studies (Shores et al. 2012, Muraleedharan et al. 2013, Vigen et al. 2013) leaves open the possibility for residual confounding and multiple other sources of bias. These have been elegantly summarised by Wu (2012).
  • Effects of testosterone therapy on body composition were metabolically favourable with modest decreases in fat mass and increases in lean body mass
  • This suggests that testosterone has limited effects on glucose metabolism in relatively healthy men with only mildly reduced testosterone.
  • it is conceivable that testosterone treatment may have more significant effects on glucose metabolism in uncontrolled diabetes, akin to what has generally been shown for conventional anti-diabetic medications.
  • the evidence from controlled studies show that testosterone therapy consistently reduces fat mass and increases lean body mass, but inconsistently decreases insulin resistance.
  • Interestingly, testosterone therapy does not consistently improve glucose metabolism despite a reduction in fat mass and an increase in lean mass
  • the majority of RCTs (recently reviewed in Ng Tang Fui et al. (2013a)) showed that testosterone therapy does not reduce visceral fat
    • Nathan Goodyear
      Nathan Goodyear on 04 Feb 14
       
      visceral and abdominal adiposity are biologically different and thus the risks associated with the two are different.
    • Nathan Goodyear
      Nathan Goodyear on 04 Feb 14
       
      yet low T is associated with an increase in visceral adiposity--confusing!
  • testosterone therapy decreases SHBG
  • testosterone is inversely associated with total cholesterol, LDL cholesterol and triglyceride (Tg) levels, but positively associated with HDL cholesterol levels, even if adjusted for confounders
  • Although observational studies show a consistent association of low testosterone with adverse lipid profiles, whether testosterone therapy exerts beneficial effects on lipid profiles is less clear
  • Whereas testosterone-induced decreases in total cholesterol, LDL cholesterol and Lpa are expected to reduce cardiovascular risk, testosterone also decreases the levels of the cardio-protective HDL cholesterol. Therefore, the net effect of testosterone therapy on cardiovascular risk remains uncertain.
  • data have not shown evidence that testosterone causes prostate cancer, or that it makes subclinical prostate cancer grow
  • compared with otherwise healthy young men with organic androgen deficiency, there may be increased risks in older, obese men because of comorbidities and of decreased testosterone clearance
  • recent evidence that fat accumulation may be oestradiol-, rather than testosterone-dependent
Nathan Goodyear

JAMA Network | JAMA: The Journal of the American Medical Association | Effects of Dieta... - 0 views

jama.jamanetwork.com/article.aspx

low carb low carbohydrate diet calories overweight obesity weight-loss energy

shared by Nathan Goodyear on 27 Jun 12 - No Cached
  • Nathan Goodyear on 27 Jun 12
     
    small study shows that low carb results in greater calories burned in weight loss.  The least calories burned goes to low fat diet.  Many, many studies have show the negative benefits of a low fat diet.
Nathan Goodyear

Testosterone Deficiency in Young Men: Marked Alterations in Whole Body Protein Kinetics... - 0 views

press.endocrine.org/...jcem.83.6.4892

low T low Testosterone muscle muscle mass strength fat obesity adipose tissue metabolism hormone hormones men male

shared by Nathan Goodyear on 06 Mar 15 - No Cached
  • Nathan Goodyear on 06 Mar 15
     
    low T in men, small study, found to decrease muscle growth, decreased strength as a result, decrease in fat oxidation/breakdown and increase in fat stores.  Low T turns the muscle:fat ratio in men upside down--the result is a metabolic derailment.
Nathan Goodyear

Effect of Distinct Lifestyle Interventions on Mobilization of Fat Storage Pools: The CE... - 0 views

circ.ahajournals.org/...CIRCULATIONAHA.117.030501

Mediterranean diet diet nutrition lifestyle obesity lifestyle intervention weight loss

shared by Nathan Goodyear on 19 Dec 17 - No Cached
  • Nathan Goodyear on 19 Dec 17
     
    low carb mediterranean nutrition out performs low fat diet; but both are not served by following weight number.  MRI shows that fat mobilization of the superior low carb mediterranean nutrition plan is not adequately reflected in weight measurement. 
Nathan Goodyear

High aromatase activity in hypogonadal men is associated with higher spine bone mineral... - 0 views

www.ncbi.nlm.nih.gov/...26142101

aromatase activity hypogonadal men low T low Testosterone fat obesity obese lean body mass muscle BMD men male hormoens

shared by Nathan Goodyear on 06 Jul 15 - No Cached
  • Nathan Goodyear on 06 Jul 15
     
    Only abstract available here--high Estradiol:Testosterone, thus high aromatase activity, increased abdominal fat and reduced lean muscle mass.  The authors also reported an higher bone mineral density, but that pales in the comparison of the metabolic dysfunction of high fat and low muscle mass causes.
Nathan Goodyear

Testosterone deficiency and cardiovascular mortality Morgentaler A, - Asian J Androl - 0 views

www.ajandrology.com/preprintarticle.asp

testosterone low t low Testosterone CVD cardiovascular mortality therapy

shared by Nathan Goodyear on 01 Dec 14 - No Cached
  • overall mortality and CV mortality were inversely associated with serum T concentrations.
  • men with low serum T, defined as < 8.7 nmol l−1 (250 ng dl−1 ), demonstrated significantly greater all-cause mortality than men with higher serum T (hazard ratio [HR]: 2.24; 95% CI: 1.41-3.57), as well as greater CV mortality
  • lower T levels were significantly associated with the presence of any CV disease
  • ...19 more annotations...
  • more than 30 years of studies suggesting that low levels of T represent an increased risk for CV and overall mortality,
  • lower serum T concentrations also are associated with CV disease, including incident coronary artery disease [17],[18],[19] and atherosclerosis,
  • the actual rate of adverse events was only half as great in the T group (123 events in 1223 men at risk = 10.1%) as in the untreated group (1587 events in 7486 men = 21.2%)
  • The study by Vigen et al. [7] has already undergone two published corrections,
  • 29 medical societies have called for retraction of the article, asserting "gross data mismanagement and contamination," that rendered the study "no longer credible
  • Mortality in T-treated men was reduced by approximately half in treated men compared with untreated men, at 10.3% versus 20.7%, respectively
  • The mortality rate for men who received TTh was 3.4 deaths per 100 person-years, and 5.7 deaths per 100 person-years in untreated men
  • HR of 0.61 (95%CI: 0.42-0.88; P = 0.008), indicating a significant reduction in mortality with TTh
  • men in the highest prognostic MI risk quartile, treatment with TTh was associated with reduced risk
  • tripling in T prescriptions in the US over the last decade
  • a majority of observational studies have found that low endogenous serum T levels are associated with increased mortality.
  • Men who received TTh were able to exercise significantly longer without ischemia compared with men who received placebo
  • In men with congestive heart failure, those who received T demonstrated greater walking distance and other functional endpoints compared with those who received placebo
  • TTh has been shown uniformly and repeatedly to improve several known CV risk factors, including reduced fat mass, body fat percent, and waist circumference, and increased lean mass
  • improved glycemic control
  • reductions in insulin resistance.
  • the evidence strongly points to improved CV status with normal serum T or treatment with TTh in men with TD
  • analysis of health insurance claims data that reported a 36% increased rate of nonfatal MI in the 90d following receipt of a T prescription compared with the 12 prior months.
  • Comparison with men who received a prescription for a phosphodiesterase type 5 inhibitor (PDE5i) revealed no increased rate of MI following the prescription
  • Nathan Goodyear on 01 Dec 14
     
    Great review by Morgentaler of Testosterone and CVD.  He highlights the significant flaws in the JAMA and the NEJM articles of Testosterone therapy risks.  Morgentaler highlights the significant evidence that points to low T and increased risk of CVD. On contention I have, is Morgantaler seems to flip aside the massive uptick of Testosterone use in the US as compared to other countries.  The evidence definitely points to Testosterone therapy as being safe in those with low T, but there is definitely a problem of significant Testosterone doping that is taking place as well.
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