Testosterone administration to men increases hepatic lipase activity and decreases HDL and LDL size in 3 wk

Causal effects of omega-6 and LDL-C on androgenetic alopecia: A Mendelian randomization study

BACKGROUND

Increasing studies have reported a causal relationship between androgenetic alopecia (AGA) and lipid-related metabolites. However, the relationships between HDL-C, LDL-C, Omega-6, and Omega-3 with AGA remain unclear. Some research findings are even contradictory. Therefore, we designed this study to explore this issue.

METHODS

In this study, we selected seven exposure factors, screened SNPs with significant associations, removed linkage disequilibrium and weak instrumental variables, and conducted bidirectional MR analysis.

RESULTS

The study found that omega-6 and LDL-C, especially total cholesterol in medium LDL and total cholesterol in small LDL, are risk factors for the occurrence of androgenetic alopecia.

CONCLUSION

In summary, we found that various lipid-related metabolites have a causal relationship with the occurrence of androgenetic alopecia, providing new insights into the pathogenesis of androgenetic alopecia and offering references for clinical treatment of androgenetic alopecia.

Proatherogenic changes in lipoprotein particles associated with a high triglyceride to high-density lipoprotein cholesterol ratio in youths

OBJECTIVE

A high triglyceride (TG) to high-density lipoprotein cholesterol (HDL) ratio (TG/HDL) predicts atherosclerosis and cardiovascular events. This study examined whether a proatherogenic distribution of plasma lipoprotein subclasses is associated with a high TG/HDL ratio in youths with obesity.

METHODS

Lipoprotein particle concentration and size were measured by proton nuclear magnetic resonance in a multiethnic cohort of 592 adolescents with overweight/obesity (age 13 ± 3 years, 58% females, BMI z score 2.1 ± 0.8) who were phenotyped with a 3-hour oral glucose tolerance test and abdominal magnetic resonance imaging.

RESULTS

The highest TG/HDL quartile showed a higher particle concentration of very low-density lipoprotein (VLDL; +178%, p < 0.0001), intermediate-density lipoprotein (+338%, p < 0.0001), and low-density lipoprotein (LDL; +42%, p < 0.0001), compared with the lowest quartile. The prevalence of large VLDL, very small LDL, and small HDL progressively increased across TG/HDL quartiles. The TG/HDL ratio correlated positively with the average particle size of VLDL (r = 0.37, p < 0.0001) and negatively with particle size of both LDL (r = -0.51, p < 0.0001) and HDL (r = -0.69, p < 0.0001). These associations were independent of sex, age, race/ethnicity, body mass, fasting plasma glucose, and insulin sensitivity.

CONCLUSIONS

In youths with obesity, an elevated TG/HDL ratio is associated with high concentrations of proatherogenic lipoprotein subclasses. This phenotype may explain the increased cardiovascular risk associated with a high TG/HDL ratio.

Skeptical Look at the Clinical Implication of Metabolic Syndrome in Childhood Obesity

Metabolic syndrome (MetS) is defined by a cluster of several cardio-metabolic risk factors, specifically visceral obesity, hypertension, dyslipidemia, and impaired glucose metabolism, which together increase risks of developing future cardiovascular disease (CVD) and type 2 diabetes mellitus (T2D). This article is a narrative review of the literature and a summary of the main observations, conclusions, and perspectives raised in the literature and the study projects of the Working Group of Childhood Obesity (WGChO) of the Italian Society of Paediatric Endocrinology and Diabetology (ISPED) on MetS in childhood obesity. Although there is an agreement on the distinctive features of MetS, no international diagnostic criteria in a pediatric population exist. Moreover, to date, the prevalence of MetS in childhood is not certain and thus the true value of diagnosis of MetS in youth as well as its clinical implications, is unclear. The aim of this narrative review is to summarize the pathogenesis and current role of MetS in children and adolescents with particular reference to applicability in clinical practice in childhood obesity.

Misadventures in Toxicology: Concentration Matters for Testosterone-Induced Neurotoxicity

Testosterone is the predominant androgen in men and has important physiological functions. Due to declining testosterone levels from a variety of causes, testosterone replacement therapy (TRT) is increasingly utilized, while testosterone is also abused for aesthetic and performance-enhancing purposes. It has been increasingly speculated that aside from more well-established side effects, testosterone may cause neurological damage. However, the in vitro data utilized to support such claims is limited due to the high concentrations used, lack of consideration of tissue distribution, and species differences in sensitivity to testosterone. In most cases, the concentrations studied in vitro are unlikely to be reached in the human brain. Observational data in humans concerning the potential for deleterious changes in brain structure and function are limited by their inherent design as well as significant potential confounders. More research is needed as the currently available data are limited; however, what is available provides rather weak evidence to suggest that testosterone use or abuse has neurotoxic potential in humans.

Anabolic-androgenic steroids: How do they work and what are the risks?

Anabolic-androgenic steroids (AAS) are a class of hormones that are widely abused for their muscle-building and strength-increasing properties in high, nontherapeutic, dosages. This review provides an up-to-date and comprehensive overview on how these hormones work and what side effects they might elicit. We discuss how AAS are absorbed into the circulation after intramuscular injection or oral ingestion and how they are subsequently transported to the tissues, where they will move into the extravascular compartment and diffuse into their target cells. Inside these cells, AAS can biotransform into different metabolites or bind to their cognate receptor: the androgen receptor. AAS and their metabolites can cause side effects such as acne vulgaris, hypertension, hepatotoxicity, dyslipidemia, testosterone deficiency, erectile dysfunction, gynecomastia, and cardiomyopathy. Where applicable, we mention treatment options and self-medication practices of AAS users to counteract these side effects. Clinicians may use this review as a guide for understanding how AAS use can impact health and to assist in patient education and, in some cases, the management of side effects.

Effects of Tributyrin Supplementation on Liver Fat Deposition, Lipid Levels and Lipid Metabolism-Related Gene Expression in Broiler Chickens

The objective of this study was to investigate the effects of tributyrin supplementation on liver fat metabolism in broiler chickens. Two hundred and forty broilers were randomly allocated into two experimental groups (6 replicates per treatment; 20 chickens in each replicate): the control group (CN), which received a basal diet, and the tributyrin group (TB), which received a basal diet supplemented with 1 g/kg of tributyrin. The experimental period lasted 37 days. The results showed that in the liver, broilers supplemented with tributyrin had higher content of high-density lipoprotein cholesterol (HDL-C) (p < 0.05). Liver hepatic lipase (HL), lipoprotein lipase (LPL) and total lipid (TL) activity were significantly lower than in the TB group than that in the NC group. Meanwhile, the diet supplemented with tributyrin had more lipid droplets than the NC group, whereas the TB and NC groups showed no histological abnormalities in the liver. Furthermore, the mRNA expression levels of peroxisome proliferators-activated receptor α (PPARα), proliferators-activated receptor γ (PPARγ), fatty acid synthase (FAS), LPL and adipose triglyceride lipase (ATGL) in the liver were significantly upregulated in the TB group (p < 0.05), while those of the long-chain acyl-CoA-synthetase 1 (ACSL1) mRNA between the TB group and the NC group were not different (p > 0.05). These findings indicated that the diet supplemented with tributyrin could increase fat deposition appropriately by promoting fat synthesis without causing liver tissue damage, which demonstrated that tributyrin can be considered a valid feed additive for broiler chickens.

Elevated endogenous testosterone levels are not associated with significant clinical morbidity

OBJECTIVES

To investigate the association between elevated endogenous testosterone levels and deleterious effects associated with testosterone therapy. Elevated serum testosterone levels in men receiving testosterone therapy have been associated with side effects, though precise thresholds above which these occur are unknown. Data on the association between naturally elevated endogenous testosterone levels and their physiologic effects is sparse.

METHODS

We examined National Health and Nutrition Examination Survey data between 2011-2016, analyzing men aged 18 and older not on testosterone or androgen ablation therapy, excluding men who had testosterone <300ng/dL, to compare men with elevated testosterone (>800ng/dL) to men with normal testosterone (300-800ng/dL). We used multivariable logistic and linear regressions for comparison.

RESULTS

After excluding men with testosterone levels <300ng/dl, 3,673 men met inclusion criterion. Only 146 (4%) of men had a testosterone >800ng/dL. When compared to men with normal testosterone, men with high testosterone had similar rates of sleep disorders, urinary symptoms, and depression. Men with elevated testosterone had higher hematocrit regression coefficient (βi 1.30, 95% confidence interval [CI] 0.69-1.90 P<0.01), AST (βi 8.48, 95% CI 0.31-16.66, P=0.04) and ALT (βi 12.23, 95% CI 0.70-23.77, P=0.04) compared to men with normal testosterone.

CONCLUSIONS

No association was found between higher endogenous testosterone levels and adverse events associated with testosterone therapy. Men with higher testosterone had increased hematocrit, but this was not clinically significant. This challenges what is considered a safe target for testosterone therapy and prompts future prospective studies to delineate the safety of elevated endogenous and exogenous modulated levels of testosterone.

Effect of Selective Androgen Receptor Modulator on Cholesterol Efflux Capacity, Size and Subspecies of HDL Particles

Context

Selective androgen receptor modulators (SARMs), because of their preferential muscle vs prostate selectivity, are being developed for muscle-wasting conditions. Oral SARMs suppress high-density lipoprotein cholesterol (HDL-C) but their effects on functional capacity and atherogenic potential of HDL particles are unknown.

Objective

To determine the effects of an oral SARM (OPK-88004) on cholesterol efflux capacity, HDL particle number and size, apolipoprotein particle number and size and HDL subspecies

Methods

We measured cholesterol efflux capacity (CEC); HDL particle number and size; APOB; APOA1; and protein-defined HDL subspecies associated with coronary heart disease (CHD) risk in men, who had undergone prostatectomy for low-grade prostate cancer during 12-week treatment with placebo or 1, 5, or 15 mg of an oral SARM (OPK-88004).

Results

SARM significantly suppressed HDL-C (P < .001) but HDL particle size did not change significantly. SARM had minimal effect on CEC of HDL particles (change + 0.016, –0.036, +0.070, and –0.048%/µmol-HDL/L^–1 at 0, 1, 5, and 15 mg SARM, P = .045). SARM treatment suppressed APOAI (P < .001) but not APOB (P = .077), and reduced APOA1 in HDL subspecies associated with increased (subspecies containing α2-macroglobulin, complement C3, or plasminogen) as well as decreased (subspecies containing APOC1 or APOE) CHD risk; relative proportions of APOA1 in these HDL subspecies did not change. SARM increased hepatic triacylglycerol lipase (HTGL) (P < .001).

Conclusion

SARM treatment suppressed HDL-C but had minimal effect on its size or cholesterol efflux function. SARM reduced APOA1 in HDL subspecies associated with increased as well as decreased CHD risk. SARM-induced increase in HTGL could contribute to HDL-C suppression. These data do not support the simplistic notion that SARM-associated suppression of HDL-C is necessarily proatherogenic; randomized trials are needed to determine SARM’s effects on cardiovascular events.

Sex Differences in Lipid Metabolism: Implications for Systemic Lupus Erythematosus and Cardiovascular Disease Risk

It is known that healthy women during childbearing years have a lower risk of cardiovascular disease (CVD) and coronary heart disease compared to age matched men. Various traditional risk factors have been shown to confer differential CVD susceptibilities by sex. Atherosclerosis is a major cause of CVD and mortality and sex differences in CVD risk could be due to reduced atherogenic low and very low-density lipoproteins (LDL and VLDL) and increased atheroprotective high density lipoproteins (HDLs) in women. In contrast, patients with systemic lupus erythematosus (SLE), a chronic inflammatory disease that predominately affects women, have an increased atherosclerotic and CVD risk. This increased CVD risk is largely associated with dyslipidaemia, the imbalance of atherogenic and atheroprotective lipoproteins, a conventional CVD risk factor. In many women with SLE, dyslipidaemia is characterised by elevated LDL and reduced HDL, eradicating the sex-specific CVD protection observed in healthy women compared to men. This review will explore this paradox, reporting what is known regarding sex differences in lipid metabolism and CVD risk in the healthy population and transgender individuals undergoing cross-sex hormone therapy, and provide evidence for how these differences may be compromised in an autoimmune inflammatory disease setting. This could lead to better understanding of mechanistic changes in lipid metabolism driving the increased CVD risk by sex and in autoimmunity and highlight potential therapeutic targets to help reduce this risk.

Effects of endocrine disorders on lipids and lipoproteins

Endocrine diseases may be associated with dyslipidaemia and may increase atherosclerotic cardiovascular disease (ASCVD) risk. This chapter describes changes in lipids and lipoproteins in diseases of the pituitary, thyroid, adrenal glands, ovaries, and testes, the mechanisms for these changes, ASCVD risk in these endocrine disorders, and whether treatment of the endocrine disorder improves the lipid profile and reduces ASCVD risk. Acromegaly, GH deficiency, Cushing syndrome, chronic glucocorticoid replacement, hypothyroidism, PCOS and male hypogonadism can increase LDL-C and/or TG. Marked reductions in LDL-C are associated with hyperthyroidism, and extremely low HDL-C levels with testosterone and/or other anabolic steroid abuse. Acromegaly, GH deficiency, Cushing syndrome, and chronic glucocorticoid replacement are associated with increased ASCVD risk. Treatment of acromegaly, GH deficiency, hypothyroidism, Cushing syndrome, and testosterone deficiency reduce LDL-C, although statin therapy may still be needed. Effects on ASCVD are not known.

Population-based Assessment of Cardiometabolic-related Diagnoses in Youth With Klinefelter Syndrome: A PEDSnet Study

CONTEXT

Diabetes and cardiovascular diseases are common among men with Klinefelter syndrome (KS) and contribute to high morbidity and mortality.

OBJECTIVE

To determine if cardiometabolic-related diagnoses are more prevalent among youth with KS than matched controls in a large population-based cohort.

METHODS

Secondary data analysis of electronic health records from 6 pediatric institutions in the United States (PEDSnet). Patients included all youth with KS in the database (n = 1080) and 4497 youth without KS matched for sex, age (mean 13 years at last encounter), year of birth, race, ethnicity, insurance, site, and duration of care (mean 7 years). The main outcome measures were prevalence of 5 cardiometabolic-related outcomes: overweight/obesity, dyslipidemia, dysglycemia, hypertension, and liver dysfunction.

RESULTS

The odds of overweight/obesity (OR 1.6; 95% CI 1.4-1.8), dyslipidemia (3.0; 2.2-3.9), and liver dysfunction (2.0; 1.6-2.5) were all higher in KS than in controls. Adjusting for covariates (obesity, testosterone treatment, and antipsychotic use) attenuated the effect of KS on these outcomes; however, boys with KS still had 45% greater odds of overweight/obesity (95% CI 1.2-1.7) and 70% greater odds of liver dysfunction (95% CI 1.3-2.2) than controls, and both dyslipidemia (1.6; 1.1-2.4) and dysglycemia (1.8; 1.1-3.2) were higher in KS but of borderline statistical significance when accounting for multiple comparisons. The odds of hypertension were not different between groups.

CONCLUSION

This large, population-based cohort of youth with KS had a higher odds of most cardiometabolic-related diagnoses than matched controls.

Sex hormones drive changes in lipoprotein metabolism

Women have a reduced cardiovascular disease (CVD) risk compared with men, which could be partially driven by sex hormones influencing lipid levels post puberty. The interrelationship between sex hormones and lipids was explored in pre-pubertal children, young post-pubertal cis-men/women, and transgender individuals on cross-sex-hormone treatment (trans-men/women) using serum metabolomics assessing 149 lipids. High-density lipoproteins (HDL, typically atheroprotective) were significantly increased and very-low- and low-density lipoproteins (typically atherogenic) were significantly decreased in post-pubertal cis-women compared with cis-men. These differences were not observed pre-puberty and were induced appropriately by cross-sex-hormone treatment in transgender individuals, supporting that sex hormones regulate lipid metabolism in vivo. Only atheroprotective apolipoprotein (Apo)A1 expressing lipoproteins (HDL) were differentially expressed between all hormonally unique comparisons. Thus, estradiol drives a typically atheroprotective lipid profile through upregulation of HDL/ApoA1, which could contribute to the sexual dimorphism observed in CVD risk post puberty. Together, this could inform sex-specific therapeutic strategies for CVD management.

Histologically proven hepatic steatosis associates with lower testosterone levels in men with obesity

Men with obesity often present with low testosterone (T) and sex hormone-binding globulin (SHBG) levels. Several mechanisms for this have been proposed, but as SHBG is secreted by hepatocytes and sex steroids undergo hepatic metabolization, this study investigates whether severity and histological components of nonalcoholic fatty liver disease (NAFLD) are associated with sex steroid levels in obese men. This cross-sectional study included 80 obese men (age: 46 ± 11 years; body mass index: 42.2 ± 5.5 kg m⁻²). Serum levels of total T and estradiol (E₂) were measured using liquid chromatography coupled with tandem mass spectroscopy (LC/MS-MS) and SHBG and gonadotropins by immunoassay. Liver biopsies were evaluated using Steatosis, Activity, and Fibrosis scoring. Participants with steatohepatitis had similar median (1^st quartile–3^rd quartile) total T levels (7.6 [5.0–11.0] nmol l⁻¹ vs 8.2 [7.2–10.9] nmol l⁻¹; P = 0.147), lower calculated free T (cFT) levels (148.9 [122.9–188.8] pmol l⁻¹ vs 199.5 [157.3–237.6] pmol l⁻¹; P = 0.006), and higher free E₂/T ratios (10.0 [6.4–13.9] x10^-3 vs 7.1 [5.7–10.7] x10^-3; P = 0.026) compared to men with only nonalcoholic fatty liver. Among the histological components of NAFLD, only steatosis was independently associated with total T (r_s = −0.331, P = 0.003) and cFT levels (r_s = −0.255, P = 0.025). Obese men with steatohepatitis have even lower cFT levels compared to those without, an association mainly driven by grade of steatosis. Whether this reflects a subgroup of men with a more severe obesity-related phenotype or results from direct relations between hepatic steatosis and sex steroid metabolism needs further investigation.

Cardiovascular risk and testosterone - from subclinical atherosclerosis to lipoprotein function to heart failure

The cardiovascular (CV) benefit and safety of treating low testosterone conditions is a matter of debate. Although testosterone deficiency has been linked to a rise in major adverse CV events, most of the studies on testosterone replacement therapy were not designed to assess CV risk and thus excluded men with advanced heart failure or recent history of myocardial infarction or stroke. Besides considering observational, interventional and prospective studies, this review article evaluates the impact of testosterone on atherosclerosis process, including lipoprotein functionality, progression of carotid intima media thickness, inflammation, coagulation and thromboembolism, quantification of plaque volume and vascular calcification. Until adequately powered studies evaluating testosterone effects in hypogonadal men at increased CV risk are available (TRAVERSE trial), clinicians should ponder the use of testosterone in men with atherosclerotic cardiovascular disease and discuss benefit and harms with the patients.

How the love of muscle can break a heart: Impact of anabolic androgenic steroids on skeletal muscle hypertrophy, metabolic and cardiovascular health

It is estimated 6.4% of males and 1.6% of females globally use anabolic-androgenic steroids (AAS), mostly for appearance and performance enhancing reasons. In combination with resistance exercise, AAS use increases muscle protein synthesis resulting in skeletal muscle hypertrophy and increased performance. Primarily through binding to the androgen receptor, AAS exert their hypertrophic effects via genomic, non-genomic and anti-catabolic mechanisms. However, chronic AAS use also has a detrimental effect on metabolism ultimately increasing the risk of cardiovascular disease (CVD). Much research has focused on AAS effects on blood lipids and lipoproteins, with abnormal concentrations of these associated with insulin resistance, hypertension and increased visceral adipose tissue (VAT). This clustering of interconnected abnormalities is often referred as metabolic syndrome (MetS). Therefore, the aim of this review is to explore the impact of AAS use on mechanisms of muscle hypertrophy and markers of MetS. AAS use markedly decreases high-density lipoprotein cholesterol (HDL-C) and increases low-density lipoprotein cholesterol (LDL-C). Chronic AAS use also appears to cause higher fasting insulin levels and impaired glucose tolerance and possibly higher levels of VAT; however, research is currently lacking on the effects of AAS use on glucose metabolism. While cessation of AAS use can restore normal lipid levels, it may lead to withdrawal symptoms such as depression and hypogonadism that can increase CVD risk. Research is currently lacking on effective treatments for withdrawal symptoms and further long-term research is warranted on the effects of AAS use on metabolic health in males and females.

Testosterone therapy in hypogonadal patients and the associated risks of cardiovascular events

Since the male secondary sex characters, libido and fertility are attributed to their major androgen hormone testosterone, the sub-optimum levels of testosterone in young adults may cause infertility and irregularities in their sexual behaviour. Such deficiency is often secondary to maladies involving testes, pituitary or hypothalamus that could be treated with an administration of exogenous testosterone. In the last few decades, the number of testosterone prescriptions has markedly increased to treat sub-optimal serum levels even though its administration in such conditions is not yet approved. On account of its associated cardiovascular hazards, the food and drug authority in the United States has issued safety alerts on testosterone replacement therapy (TRT). Owing to a great degree of conflict among their findings, the published clinical trials seem struggling in presenting a decisive opinion on the matter. Hence, the clinicians remain uncertain about the possible cardiovascular adversities while prescribing TRT in hypogonadal men. The uncertainty escalates even further while prescribing such therapy in older men with a previous history of cardiovascular ailments. In the current review, we analysed the pre-clinical and clinical studies to evaluate the physiological impact of testosterone on cardiovascular and related parameters. We have enlisted studies on the association of cardiovascular health and endogenous testosterone levels with a comprehensive analysis of epidemiological studies, clinical trials, and meta-analyses on the cardiovascular risk of TRT. The review is aimed to assist clinicians in making smart decisions regarding TRT in their patients.

Effectiveness of testosterone therapy in hypogonadal patients and its controversial adverse impact on the cardiovascular system

Testosterone is the major male hormone produced by testicles which are directly associated with man's appearance and secondary sexual developments. Androgen deficiency starts when the male hormonal level falls from its normal range though, in youngsters, the deficiency occurs due to disruption of the normal functioning of pituitary, hypothalamus glands, and testes. Thus, testosterone replacement therapy was already known for the treatment of androgen deficiency with lesser risks of producing cardiovascular problems. Since from previous years, the treatment threshold in the form of testosterone replacement therapy has effectively increased to that extent that it was prescribed for those conditions which it was considered as inappropriate. However, there are some research studies and clinical trials available that proposed the higher risk of inducing cardiovascular disease with the use of testosterone replacement therapy. Thus under the light of these results, the FDA has published the report of the increased risk of cardiovascular disease with the increased use of testosterone replacement therapy. Nevertheless, there is not a single trial available or designed that could evaluate the risk of cardiovascular events with the use of testosterone replacement therapy. As a result, the use of testosterone still questioned the cardiovascular safety of this replacement therapy. Thus, this literature outlines the distribution pattern of disease by investigating the data and link between serum testosterone level and the cardiovascular disease, also the prescription data of testosterone replacement therapy patients and their tendency of inducing cardiovascular disease, meta-analysis and the trials regarding testosterone replacement therapy and its connection with the risks of causing cardiovascular disease and lastly, the possible effects of testosterone replacement therapy on the cardiovascular system. This study aims to evaluate the available evidence regarding the use of testosterone replacement therapy when choosing it as a treatment plan for their patients.

A selective androgen receptor modulator SARM-2f activates androgen receptor, increases lean body mass, and suppresses blood lipid levels in cynomolgus monkeys

SARM-2f a selective androgen receptor (AR) modulator, increases skeletal muscle mass and locomotor activity in rats. This study aimed to clarify its pharmacological effects in monkeys. In reporter assays, the EC50 values of SARM-2f for rat, monkey, and human AR were 2.5, 3, and 3.6 nmol/L, respectively; those of testosterone were 12, 3.2, and 11 nmol/L, respectively. A single oral administration (10 mg/kg SARM-2f) produced a maximal plasma concentration of 3011 ng/mL, with an area under the 24 hours concentration-time curve of 8152 ng·h/mL in monkeys. Body weight (BW), lean body mass (LBM), and plasma levels of total cholesterol, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, lipoprotein (a), alanine aminotransferase, and asparagine aminotransferase were measured after 4 weeks of treatment with SARM-2f (1, 3, and 10 mg/kg/day, QD, p.o.) or testosterone enanthate (TE; 2 mg/kg/2 weeks, s.c.) in monkeys. BW and LBM were significantly increased by 12% each by SARM-2f at 10 mg/kg, and by 5% and 8%, respectively, by TE, but these effects were not statistically significant. Plasma levels of all lipids were either decreased or showed a tendency to be decreased by SARM-2f. TE decreased the triglyceride level and increased the low-density lipoprotein cholesterol level. Liver marker levels were not changed by either SARM-2f or TE. Our data demonstrated that SARM-2f exerted anabolic effects and produced a lipid profile that differed from that produced by testosterone in monkeys, suggesting that SARM-2f might be useful for diseases such as sarcopenia.

Testosterone replacement therapy and cardiovascular risk

Testosterone is the main male sex hormone and is essential for the maintenance of male secondary sexual characteristics and fertility. Androgen deficiency in young men owing to organic disease of the hypothalamus, pituitary gland or testes has been treated with testosterone replacement for decades without reports of increased cardiovascular events. In the past decade, the number of testosterone prescriptions issued for middle-aged or older men with either age-related or obesity-related decline in serum testosterone levels has increased exponentially even though these conditions are not approved indications for testosterone therapy. Some retrospective studies and randomized trials have suggested that testosterone replacement therapy increases the risk of cardiovascular disease, which has led the FDA to release a warning statement about the potential cardiovascular risks of testosterone replacement therapy. However, no trials of testosterone replacement therapy published to date were designed or adequately powered to assess cardiovascular events; therefore, the cardiovascular safety of this therapy remains unclear. In this Review, we provide an overview of epidemiological data on the association between serum levels of endogenous testosterone and cardiovascular disease, prescription database studies on the risk of cardiovascular disease in men receiving testosterone therapy, randomized trials and meta-analyses evaluating testosterone replacement therapy and its association with cardiovascular events and mechanistic studies on the effects of testosterone on the cardiovascular system. Our aim is to help clinicians to make informed decisions when considering testosterone replacement therapy in their patients.

Normative range of blood biochemical parameters in urban Indian school-going adolescents

Adolescence is the most critical phase of human growth that radically alters physiology of the body and wherein any inconsistency can lead to serious health consequences in adulthood. The timing and pace at which various developmental events occur during adolescence is highly diverse and thus results in a drastic change in blood biochemistry. Monitoring the physiological levels of various biochemical measures in ample number of individuals during adolescence can call up for an early intervention in managing metabolic diseases in adulthood. Today, only a couple of studies in different populations have investigated blood biochemistry in a small number of adolescents however, there is no comprehensive biochemical data available worldwide. In view, we performed a cross-sectional study in a sizeable group of 7,618 Indian adolescents (3,333 boys and 4,285 girls) aged between 11–17 years to inspect the distribution of values of common biochemical parameters that generally prevails during adolescence and we observed that various parameters considerably follow the reported values from different populations being 3.56–6.49mmol/L (fasting glucose), 10.60–199.48pmol/L (insulin), 0.21–3.22nmol/L (C–peptide), 3.85–6.25% (HbA₁c), 2.49–5.54mmol/L (total cholesterol), 1.16–3.69mmol/L (LDL), 0.78–1.85mmol/L (HDL), 0.33–2.24mmol/L (triglycerides), 3.56–11.45mmol/L (urea), 130.01–440.15μmol/L (uric acid) and 22.99–74.28μmol/L (creatinine). Barring LDL and triglycerides, all parameters differed significantly between boys and girls (p< 0.001). Highest difference was seen for uric acid (p = 1.3 x10^-187) followed by C–peptide (p = 6.6 x10^-89). Across all ages during adolescence, glycemic and nitrogen metabolites parameters varied markedly with gender. Amongst lipid parameters, only HDL levels were found to be significantly associated with gender following puberty (p< 0.001). All parameters except urea, differed considerably in obese and lean adolescents (p< 0.0001). The present study asserts that age, sex and BMI are the essential contributors to variability in blood biochemistry during adolescence. Our composite data on common blood biochemical measures will benefit future endeavors to define reference intervals in adolescents especially when the global availability is scarce.

Effects of testosterone enanthate treatment in conjunction with resistance training on thyroid hormones and lipid profile in male Wistar rats

This study was conducted to determine the effects of 8-week administration of testosterone enanthate (TE) in conjunction with resistance training on thyroid hormones and lipid profiles. Sixty male adult Wistar rats were randomly divided into six groups: C: olive oil, RT: resistance training + olive oil, LD: TE (20 mg/kg), HD: TE (50 mg/kg), RT + LD: RT + TE (20 mg/kg), RT + HD: RT + TE (50 mg/kg). The RT consisted of climbing (5 reps/3 sets) a ladder carrying a load suspended from the tail. At the end, blood specimens were obtained from the orbital sinus and serum concentration of T4, T3, TSH and lipid profiles was determined. The serum concentration of TSH significantly increased in RT + HD group compared to C, and the serum concentration of T4 significantly decreased in LD, HD, RT + LD and RT + HD groups compared to the C and RT groups (p < .05). The concentration of HDL and cholesterol significantly decreased in HD and RT + HD groups compared with C group (p < .05). Both decreased T4 and increased TSH in the RT + HD group likely suggested a primary hypothyroidism as a complication of high-dose administration of testosterone enanthate along with resistance training. Alteration in lipid profile was another complication observed in rats received high doses of testosterone enanthate.

The polymorphic CAG repeat in exon 1 of androgen receptor is associated with level of HDL cholesterol and hypertension in Chinese middle-aged and elderly men

OBJECTIVE

The length of the CAG repeats in exon 1 of the androgen receptor (AR) gene has been shown to be inversely correlated with AR transcriptional activity. This study aimed to investigate the correlations between the length of CAG repeat in AR and serum lipids and hypertension in Chinese men.

DESIGN AND PATIENTS

The relationship between length of the CAG repeat in exon 1 of AR with prevalence of hypertension and the levels of serum lipids among Chinese men (aged ≥40 years).

MEASUREMENTS

The physical condition of the subjects was examined and recorded. The concentrations of blood lipids and sex hormones were measured, and the CAG repeat lengths of the AR gene were determined.

RESULTS

The length of the AR CAG repeats was associated with HDL cholesterol (HDL-C) concentration, and the stepwise multiple regression model showed that this association was independent of body mass index (BMI), triglycerides (TG) and total cholesterol (TC), although these factors influence HDL-C concentration. Furthermore, men with <22 vs men with ≥22 CAG repeats showed higher blood pressure and higher prevalence of hypertension. Shorter CAG repeat numbers were associated with the increased risk of hypertension in a multivariate logistic regression analysis (odds ratio = 0·715; 95% confidence interval, 0·517-0·989; P = 0·043). No significant correlation of AR CAG repeat polymorphism with sex hormone levels, TG, LDL cholesterol (LDL-C) or TC was found.

CONCLUSIONS

This study provides evidence that men carrying shorter (<22) AR CAG repeats have lower HDL-C level and increased risk of hypertension. The androgenic activity may differ due to the polymorphic length of CAG repeats of the AR gene.

Effects of testosterone administration on liver structure and function in aging rats

Aging males have a decrease in testosterone levels, by which the testosterone treatment may influence in a negatively fashion the liver.

AIM

This study aimed to analyze the effects of aging with or without testosterone administration on the liver components of animals.

METHODS

Wistar rats were divided into three groups: 20 months' group (G20), 24 months' group (G24), group treated with testosterone for 16 weeks (GT). All groups were sacrificed at 24 months except for G20 that was sacrificed at 20 months.

RESULTS

Aging and testosterone treatment alters the body weight (BW), liver weight (LW) and relative liver weight. Besides, testosterone increased the mitogen capacity of hepatocytes. Nonetheless, we reinforce the negative effects of testosterone on old animals' liver as chronic hepatic congestion and/or cholestasis. In addition, we observed that testosterone plays an important role on hepatic glycogen stores.

CONCLUSIONS

Our study showed many implications for the knowledge about the effects of aging with or without testosterone administration on old animals' liver.

Controversial Effects of Exogenous Testosterone on Cardiovascular Diseases

The use of testosterone (T) among men aged 40 years or older was increased more than 3 times from 0.81% in 2001 to 2.91% in 2011. Until recently, the majority of the studies did not show any increased cardiovascular (CV) risk by using T in male patients with hypogonadism. What is more, some studies had observed a protective effect of using T against CV diseases. However, in 2010, a randomized clinical trial (RCT) was intended to study the advantage of T gel in older men with limitations in mobility; the study was stopped due to unexpected high prevalence of CV adverse outcome. These findings were confirmed by 2 other studies published in November of 2013 and January of 2014. Consequently, the Food and Drug Administration (FDA) had announced in January 2014 that it will reassess the safety of those treatments. Meanwhile, the agency had not reached to a definitive conclusion that FDA-approved testosterone therapy raises the risk of stroke, heart attack, or death. A report released in the broadcast of the NBC Nightly News in September of this year that the FDA says "there's little evidence that T boosting drugs taken by millions of American men are actually effective." NBC notes that the agency also pointed out that it was not convinced that they carry serious risk either. "The condition has been marketed as low 'T', and the medications are offered to help with low sex drive and fatigue among some men," notes NBC. The European Medicines Agency EMA's Pharmacovigilance Risk Assessment Committee has also responded to the concern of potential CV adverse outcomes associated with the use of T, and they have concluded in their October meeting of this year that the use of T in men who do not produce enough T raises the risk of heart diseases. In our review, we highlighted the association between exogenous T and major adverse CV outcomes. Additionally, we focused on the interplay between exogenous T and some endocrine abnormalities such as diabetes mellitus type 2, metabolic syndrome, dyslipidemia, and obesity.

An update on the assessment and management of metabolic syndrome, a growing medical emergency in paediatric populations

In the last decades the increasing rate of obesity in children and adolescents worldwide has led to the onset in paediatric age of metabolic syndrome, a disease commonly associated to adulthood. Central obesity, dyslipidaemia, hyperglycaemia, and hypertension are typical features of metabolic syndrome that seem to hesitate often in type 2 diabetes, cardiovascular disease, non-alcoholic fatty liver disease, and many other clinical conditions. Thus preventing and curing metabolic syndrome in paediatric patients is becoming an urgent need for public health. While diagnostic criteria and therapy of metabolic syndrome in adults are very well defined, there is no consensus on the definition of metabolic syndrome in children and adolescents as well as on healing approaches. The aim of this review is to describe the recent advances on the pathogenesis and clinical outcomes of paediatric metabolic syndrome. We then detail the therapeutic strategies (i.e. dietary regimens, physical exercise, nutraceuticals, and medications) employed to manage the disease. Finally, we analyse the safety profile of the drugs used in children and adolescents by performing a retrospective review of paediatric adverse reactions reported in the FDA's Adverse Event Reporting System database.

Metabolic Syndrome: Bridging the Gap from Childhood to Adulthood

Childhood and adolescence are particularly vulnerable periods of life to the effects of cardiometabolic risk and later development of atherosclerosis, hypertension, and diabetes mellitus. Developing countries with limited resources suffer most heavily from the consequences of cardiometabolic risk in children and its future implications to the global health burden. A better understanding of mechanisms leading to cardiometabolic risk in early life may lead to more effective prevention and intervention strategies to reduce metabolic stress in children and later disease. Longitudinal "tracking" studies of cardiometabolic risk in children provide a tremendous global resource to direct prevention strategies for cardiovascular disease. In this review, we will summarize the pathophysiology, existing definitions for cardiometabolic risk components in children. Screening and identifying children and adolescents of high cardiometabolic risk and encouraging them and their families through healthy lifestyle changes should be implemented to as a global public health strategy.

(-)-Hydroxycitric acid reduced fat deposition via regulating lipid metabolism-related gene expression in broiler chickens

BACKGROUND

Chicken as a delicious food for a long history, and it is well known that excess fat deposition in broiler chickens will not only induced metabolic diseases, but also lead to adverse effect in the consumer's health. (-)-Hydroxycitric acid (HCA), a major active ingredient of Garcinia Cambogia extracts, had shown to suppress fat accumulation in animals and humans. While, the precise physiological mechanism of HCA has not yet been full clarified, especially its action in broiler chickens. Thus, this study aimed to assess the effect of (-)-HCA on lipid metabolism in broiler chickens.

METHODS

A total of 120 1-day-old broiler chickens were randomly allocated to four groups, with each group was repeated three times with 10 birds. Birds received a commercial diet supplemented with (-)-HCA at 0, 1000, 2000 or 3000 mg/kg, respectively, for a period of 4 weeks ad libitum.

RESULTS

Body weight (BW) in the 2000 and 3000 mg/kg (-)-HCA groups was significantly decreased (P < 0.05) than that in control group. A significantly decreased of serum triglyceride (TG) and density lipoprotein-cholesterol (LDL-C) content were observed in 3000 mg/kg (-)-HCA group (P < 0.05). Broiler chickens supplmented with 2000 and 3000 mg/kg (-)-HCA had pronouncedly higher hepatic lipase (HL) activity, hepatic glycogen and non-esterified fatty acid (NEFA) contents in liver (P < 0.05). Serum free triiodothyronine (FT3) and thyroxin (T4) contents were significantly higher in 3000 mg/kg (-)-HCA group (P < 0.05) compared with the control group. Supplemental (-)-HCA markedly decreased fatty acid synthase (FAS) and sterol regulatory element binding protein-1c (SREBP-1c) (P < 0.05) mRNA levels, while the mRNA abundance of adenosine 5'-monophosphate-activated protein kinaseβ2 (AMPKβ2) (P < 0.05) was significantly increased. In addition, ATP-citrate lyase (ACLY) mRNA level (P < 0.05) was significantly decreased in broiler chickens supplemented with 3000 mg/kg (-)-HCA. No differences was observed on carnitine palmitoyl transferase-I(CPT-I), while peroxisome proliferators-activated receptor α (PPARα) mRNA level (P < 0.05) was significantly increased in broiler chickens supplemented with 2000 and 3000 mg/kg (-)-HCA.

CONCLUSIONS

Supplemental (-)-HCA inhibited lipogenesis by inhibiting ACLY, SREBP-1c and FAS expression, and accelerated lipolysis through enhancing HL activity and PPARα expression, which eventually led to the reduced abdominal fat deposition in broiler chickens. Graphical abstract Mechanism of (-)-HCA effect on hepatic lipids metabolism.

Aging and dyslipidemia: a review of potential mechanisms

Elderly adults constitute a rapidly growing part of the global population, thus resulting in an increase in morbidity and mortality related to cardiovascular disease (CVD), which remains the major cause of death in elderly population, including men and women. Dyslipidemia is a well-established risk factor for CVD and is estimated to account for more than half of the worldwide cases of coronary artery disease (CAD). Many studies have shown a strong correlation between serum cholesterol levels and risk of developing CAD. In this paper, we review the changes of plasma lipids that occur in men and women during aging and the potential mechanisms of age-related disorders of lipoprotein metabolism covering humans and/or animals, in which changes of the liver sinusoidal endothelium, postprandial lipemia, insulin resistance induced by free fatty acid (FFA), growth hormone (GH), androgen (only for men) and expression and activity of peroxisome proliferator-activated receptor α (PPARα) are mainly focused.

Cardiovascular disease risk in young Indian women with polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is associated with significant risk factors for cardiovascular disease (CVD) like insulin resistance, hyperinsulinism, hypertension and dyslipidemia. We studied CVD risk in young women (18-35 years age) with PCOS using carotid intima media thickness (CIMT) and brachial artery flow mediated dilation (FMD) which are markers of subclinical atherosclerosis. Fifty women with PCOS (age: 24.3 ± 4 years; body mass index [BMI]: 24.6 ± 4 kg/m(2)) were compared with 50 age and BMI matched healthy controls (age: 24.6 ± 5 years; BMI: 23.9 ± 4 kg/m(2)). CIMT was significantly higher (0.55 ± 0.09 mm versus 0.40 ± 0.1 mm, p value <0.0001) and FMD was significantly lower (9.39 ± 4.36% versus 13.89 ± 4.77%, p value <0.0001) in cases as compared to controls. These differences in CIMT and FMD remained significant when subgroup were analyzed, obese PCOS versus obese controls and non obese PCOS versus non-obese controls. In stepwise linear regression PCOS was associated with CIMT and FMD independent of age, BMI and blood pressure. Young women with PCOS irrespective of their BMI have evidence for increased CVD risk as shown by increased CIMT and a lower FMD.

Is bilateral orchiectomy for metastatic prostate cancer treatment associated with high cardiovascular risk?

Cardiovascular disease is one of the most common causes of death worldwide and the most usual in the western populations. Although it affects both sexes, it is more frequent in males in whom it shortens the average life expectancy. This difference has been attributed to the negative effects of testosterone; however, recent research showed that this hormone may have protective effects on the cardiovascular system. In confirmation to the above current evidence suggests that the low levels of testosterone could be associated with an increased CVD risk and with an augmentation of morbidity and mortality in males. In the present article, we present 2 cases of men with CVD and metastatic prostate cancer treated with bilateral orchiectomy who died of acute stroke during the perioperational period. The possible association of androgen deprivation with cardiovascular disease progression and the consequent risk of stroke are briefly discussed.

Hormone replacement therapy and physical function in healthy older men. Time to talk hormones?

Improving physical function and mobility in a continuously expanding elderly population emerges as a high priority of medicine today. Muscle mass, strength/power, and maximal exercise capacity are major determinants of physical function, and all decline with aging. This contributes to the incidence of frailty and disability observed in older men. Furthermore, it facilitates the accumulation of body fat and development of insulin resistance. Muscle adaptation to exercise is strongly influenced by anabolic endocrine hormones and local load-sensitive autocrine/paracrine growth factors. GH, IGF-I, and testosterone (T) are directly involved in muscle adaptation to exercise because they promote muscle protein synthesis, whereas T and locally expressed IGF-I have been reported to activate muscle stem cells. Although exercise programs improve physical function, in the long-term most older men fail to comply. The GH/IGF-I axis and T levels decline markedly with aging, whereas accumulating evidence supports their indispensable role in maintaining physical function integrity. Several studies have reported that the administration of T improves lean body mass and maximal voluntary strength in healthy older men. On the other hand, most studies have shown that administration of GH alone failed to improve muscle strength despite amelioration of the detrimental somatic changes of aging. Both GH and T are anabolic agents that promote muscle protein synthesis and hypertrophy but work through separate mechanisms, and the combined administration of GH and T, albeit in only a few studies, has resulted in greater efficacy than either hormone alone. Although it is clear that this combined approach is effective, this review concludes that further studies are needed to assess the long-term efficacy and safety of combined hormone replacement therapy in older men before the medical rationale of prescribing hormone replacement therapy for combating the sarcopenia of aging can be established.

Testosterone and coronary artery disease

Cardiovascular disease remains the leading cause of death in most of the developed world despite advances in both prevention and treatment. At the same time, the incidence rates of cardiovascular disease differ greatly between the genders, with men more likely than women to manifest ischemic heart disease. This observation has prompted new research initiatives to explain the discrepancy in heart disease prevalence and incidence between the sexes. Whether androgens affect cardiovascular disease adversely remains a contentious issue, with some data pointing to a deleterious effect of androgens on lipid profiles, and other studies revealing androgens' possible benefits on cardiovascular function. This review will examine the relationship between the endogenous production of androgen as well as the exogenous replacement of testosterone in men and the possible links to cardiovascular disease. The role of testosterone in male cardiovascular health is not completely understood, and additional studies are needed to explain its effect on atherosclerosis and its complications.

Male hormonal contraception: potential risks and benefits

An effective, safe, reversible, and acceptable method of contraception is an important component of reproductive health and provides the opportunity of shared responsibility for family planning for both partners. Female hormonal contraceptives have been proven to be safe, reversible, available and widely acceptable by different populations. In contrast, male hormonal contraception, despite significant progress showing contraceptive efficacy comparable to female hormonal methods during last three decades, has not yet led to an approved product. Safety of a pharmaceutical product is an appropriate concern but the majority of male hormonal contraceptive clinical trials have not reported significant short term safety concerns. While the absence of serious adverse effects is encouraging, the studies have been designed for efficacy endpoints not long term safety. In this review we summarize potential risks and benefits of putative male hormonal contraceptives on reproductive and non-reproductive organs. While the review covers what we believe will be the likely class of drugs used for male hormonal contraception a true assessment of long term risks and benefits cannot be achieved without an available product.

A higher burden of small low-density lipoprotein particles is associated with profound changes in the free androgen index in male adolescents

From a young age, males are at higher cardiovascular risk than females. Dyslipidemia, including a higher burden related to small low-density lipoproteins (LDL), plays an important role in precipitating atherosclerosis in both males and females. We investigated sex differences in atherogenic lipoprotein burden and the independent predictors of LDL particle size in children and adolescents. We measured the concentrations of total testosterone, sex hormone-binding globulin, estradiol, total cholesterol, triglyceride, LDL cholesterol, HDL cholesterol, and LDL particle size in 135 children and adolescents (67 boys, 68 girls). The free androgen index was significantly and negatively correlated with LDL particle size (r = -0.273, P = 0.026) in boys, but estrogen and LDL particle size were not related. In a stepwise multiple regression analysis adjusted for body mass index, age, and homeostasis model assessment for insulin resistance, free androgen index was still an independent predictor of LDL particle size in boys (R(2) = 0.075, P = 0.026). The prominent decrease in LDL particle size along with increased testosterone concentrations in males might explain why they are more likely to display atherogenic dyslipidemia from adolescence.

Aging Men and Lipids

Many theories aim at explaining the mechanisms of aging and death in humans. Decreased levels of androgens, growth hormone, and insulin-like growth factor accompany natural aging in men. Androgens influence the growth and maturation of men in various stages of their life. The action of androgens is performed by binding or not binding to androgen receptors. However, various actions of androgens were clarified after the discovery and genotyping of the androgen receptor. The influence of androgens on the lipid profile was reported by several researchers. This negative influence of androgens in men and the positive influence of estrogens in women are responsible for the higher impact of atherogenesis in men compared with women. In aging men, this negative influence of androgens on the lipid profile is more pronounced. This review considers the influence of age on lipid metabolism in men.

Androgen deficiency and atherosclerosis: The lipid link

The relationship between androgen deficiency and atherosclerosis is complex, poorly understood, and remains controversial. The aim of this review is to evaluate the data in the literature to determine if androgen deficiency modulates lipid profiles and contributes to atherosclerosis development or progression. Studies in animals and humans suggest that androgen deficiency is associated with increased triglycerides (TGs), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C). Although the effects of androgen deficiency on high-density lipoprotein cholesterol (HDL-C) remains controversial, recent data suggest that androgen therapy is associated with increased levels of HDL-C and may improve reverse cholesterol transport. Animal studies suggested that androgen deprivation adversely affect lipid profiles and this was reversed by androgen treatment. Furthermore, androgen treatment of hypogonadal men significantly improved lipid profiles. Emerging data indicate that androgens play an important role in lipid metabolism. Therefore androgens are critical in the prevention and progression of atherosclerosis. Androgen deficiency contributes to increased TGs, TC, LDL-C and reduced HDL-C while androgen treatment results in a favorable lipid profile, suggesting that androgens may provide a protective effect against the development and/or progression of atherosclerosis.

HDL-ApoE content regulates the displacement of hepatic lipase from cell surface proteoglycans

Human hepatic lipase (HL) is an interfacial enzyme that must be liberated from cell surface proteoglycans to hydrolyze lipoprotein triglyceride. Both high-density lipoprotein (HDL) and apolipoprotein (apo)A-I can displace HL from cell surface proteoglycans, much like heparin. HL displacement is inhibited by HDL-apoE content. Postprandial HDL is approximately twofold better at displacing HL than is fasting HDL, but only has approximately one-half the apoE content. Enriching native HDL with triglyceride decreases HDL-apoE content and increases HL displacement. Incubation of HDL with the anti-apoE antibody, 6C5, also increases HL displacement. In contrast, enrichment of synthetic HDL with apoE significantly inhibits HL displacement. HDL from fasted female normolipidemic subjects displaces HL approximately twofold better than HDL from male subjects. HDL from female subjects also has significantly less apoE than HDL from males. Normolipidemic females have increased circulating HDL-bound HL. Hyperlipidemia has little effect on the HL displacement ability of HDL from men, whereas HDL from hypercholesterolemic females exhibits impaired HL displacement. HL displacement from liver heparan sulfate proteoglycans therefore appears to be linked to interlipoprotein apoE exchange. Decreased HL displacement is associated with higher HDL-apoE levels and may therefore affect vascular triglyceride hydrolysis.

Low serum testosterone in men is inversely associated with non-fasting serum triglycerides: the Tromsø study

OBJECTIVE

To study the relationships between endogenous testosterone, sex hormone-binding globulin (SHBG) and serum lipids in non-fasting men.

METHODS

We performed a cross-sectional study in 1274 men without known cardiovascular disease who participated in a population-based study, the 1994/1995 Tromsø study. Anthropometric characteristics were measured and questionnaires regarding lifestyle and medical history were completed. Non-fasting blood samples were drawn between 08.00 and 16.00h, and total testosterone, SHBG, triglycerides (TG), total cholesterol (TC) and high-density lipoprotein (HDL) were analyzed.

RESULTS

In stratified analyses based on sampling time, a linear increase in serum TG levels was found in men with total testosterone levels below the 50th percentile during the day (p for trend=0.004). In contrast, serum triglycerides did not change during the day in men with testosterone levels above the 50th percentile. In regression analyses, total testosterone and SHBG were inversely and independently associated with TG (p<0.001 and p<0.001 respectively), and positively and independently associated with HDL (p=0.005 and p<0.001, respectively). Men with an unfavorable lipid profile (HDL <0.90 and TG >1.8) had significantly lower levels of total testosterone and SHBG (p=0.004 and p<0.001, respectively) in age and BMI adjusted analyses, compared to men with a normal lipid profile.

CONCLUSIONS

Low serum total testosterone was associated with a linear increase in serum TG during the day, and was independently associated with an unfavorable lipid profile. Our findings may indicate that low total testosterone is associated with impaired TG metabolism in men.

Gene expression analyses in cynomolgus monkeys provides mechanistic insight into high-density lipoprotein-cholesterol reduction by androgens in primates

Androgens increase muscle mass, decrease fat mass, and reduce high-density lipoprotein cholesterol (HDL), but the relationship between body composition, lipoprotein metabolism, and androgens has not been explained. Here we treated ovariectomized cynomolgus monkeys with 5alpha-dihydrotestosterone (DHT) or vehicle for 14 d and measured lipoprotein and triglycerides. Nuclear magnetic resonance analysis revealed that DHT dose-dependently reduced the cholesterol content of large HDL particles and decreased mean HDL particle size (P < 0.01) and also tended to lower low-density lipoprotein cholesterol without altering other lipoprotein particles. Liver and visceral fat biopsies taken before and after DHT treatment for 1 or 14 d were analyzed by genome-wide microarrays. In liver, DHT did not alter the expression of most genes involved in cholesterol synthesis or uptake but rapidly increased small heterodimer partner (SHP) RNA, along with concomitant repression of CYP7A1, a target of SHP transcriptional repression and the rate-limiting enzyme in bile acid synthesis. DHT regulation of SHP and CYP7A1 also occurs in rats, indicating a conserved mechanism. In adipose tissue, pathway analyses suggested coordinate regulation of adipogenesis, tissue remodeling, and lipid homeostasis. Genes encoding IGF-I and beta-catenin were induced, as were extracellular matrix, cell adhesion, and cytoskeletal components, whereas there was consistent down-regulation of genes involved in triacylglycerol metabolism. Interestingly, cholesterol ester transfer protein RNA was induced rapidly in monkey adipose tissue, whereas its inhibitor apolipoprotein CI was repressed. These data provide insight into the androgenic regulation of lipoprotein homeostasis and suggest that changes in adipose lipoprotein metabolism could contribute to HDL cholesterol reduction.

Higher testosterone levels are associated with increased high-density lipoprotein cholesterol in men with cardiovascular disease: results from the Massachusetts Male Aging Study

AIM

To study the relationship between circulating androgens (total testosterone [TT], free testosterone [fT] and dihydrotestosterone [DHT]) and high-density lipoprotein cholesterol (HDL-C) in men with and without cardiovascular disease (CVD).

METHODS

Cross-sectional analyses included 1 661 baseline samples from the Massachusetts Male Aging Study (MMAS), a population-based cohort of men ages 40-70 years. Serum hormones were measured by radioimmunoassay and HDL-C was determined following precipitation of the lower density lipoproteins. CVD was determined by self-report. Analyses were performed using multiple linear regression.

RESULTS

TT and HDL-C were positively correlated in the entire sample (r=0.11, P=0.0001). After adjusting for confounders, we found this relationship was mostly limited to the 209 men with CVD. Among men with CVD, TT (P=0.0004), fT (P=0.0172) and DHT (P=0.0128) were all positively correlated with HDL-C, whereas in men without CVD only TT correlated with HDL-C (P=0.0099).

CONCLUSION

Our results suggest that if androgens contribute to CVD in middle-aged men, the effect is not related to a suppressive effect of endogenous T on HDL-C.

Pathophysiology and types of dyslipidemia in PCOS

Polycystic ovary syndrome (PCOS) is an endocrinopathy that affects women of reproductive age. PCOS shares components with the metabolic syndrome and has broad health implications. Lipid abnormalities, including elevated low-density lipoprotein (LDL), triglyceride levels and decreased high-density lipoprotein (HDL), are often found in women with PCOS. It is clear that obesity, insulin resistance and hyperandrogenism coexist in PCOS, and have independent and interactive effects on dyslipidemia, although the mechanisms of these interactions remain elusive. Here, we review the types and pathophysiology of dyslipidemia associated with PCOS and its related conditions.

Effects of Dehydroepiandrosterone (DHEA) on Hepatic Lipid Metabolism Parameters and Lipogenic Gene mRNA Expression in Broiler Chickens

The aim of the present study was to identify the effects of dehydroepiandrosterone (DHEA) on hepatic lipid metabolism parameters and lipogenic gene mRNA expression in broiler chickens. A total of 72 1-day-old broiler chicks received a common basal diet with DHEA added at either 0 (control), 5 or 20 mg/kg feed. In the present study, the hepatic triglyceride (TG) concentration was significantly lower in male and female broilers that had bed administered DHEA than in control birds. In contrast, DHEA administration caused a marked rise in the hepatic non-esterified fatty acid (NEFA) concentration in both male and female broilers and also increased lipase (HL) activity in male broilers, while in female birds, no significant differences were observed in HL activity. The expression of peroxisome proliferators-activated receptor alpha (PPARalpha) and carnitine palmitoyl transferase I (CPTI) mRNA was decidedly enhanced following treatment with DHEA, and a similar tendency was also observed in the expression of acyl-Coenzyme A oxidase 1 (ACOX1). However, no significant differences were observed in the expression of either sterol regulatory element binding protein-1c (SREBP-1c) or acetyl CoA carboxylase (ACC) mRNA, except for a decline in the expression of ACC in females treated with 5 mg DHEA/kg. Numerous peroxisomes without a core and an increased number of peroxisomes were evident during morphological observations of broiler livers, in animals that had been treated with DHEA. Overall, the results of the present study indicated that DHEA accelerated lipid catabolism by direct regulation of hepatic lipid metabolism and by induction of relevant gene expression.

Testosterone gel combined with depomedroxyprogesterone acetate is an effective male hormonal contraceptive regimen and is not enhanced by the addition of a GnRH antagonist

INTRODUCTION

Exogenous androgens plus progestins can be used to suppress spermatogenesis, resulting in effective male hormonal contraception; however, induction of azoospermia can require 3-6 months, and these methods require injectable or implantable androgens. We hypothesized that testosterone (T) transdermal gel (T gel) could be combined with a depot formulation of the progestin, depomedroxyprogesterone acetate (DMPA), with or without the potent GnRH antagonist, acyline, to suppress spermatogenesis conveniently, rapidly, and reversibly.

OBJECTIVES

The objectives of the study were: 1) to determine the rate of severe oligospermia (< or = 1 million sperm/ml) using T gel+DMPA; and 2) to determine whether the addition of acyline to T gel+DMPA during the first 12 wk of the regimen would accelerate and improve suppression of spermatogenesis.

METHODS

Forty-four healthy men, ages 18-55 yr, were randomized to T gel (100 mg daily)+DMPA (300 mg/3 months) or acyline (300 microg/kg.2 wk x 12 wk)+T gel+DMPA. Thirty-eight men completed the 24-wk treatment protocol.

RESULTS

All men had dramatic suppression of spermatogenesis; 90% of the subjects became severely oligospermic, a rate comparable to implantable and injectable T+progestin combinations. The addition of acyline did not significantly accelerate spermatogenic suppression or improve rates of severe oligospermia. There were no serious adverse events, and there were minimal changes in weight, serum lipids, and prostate-specific antigen.

CONCLUSIONS

The combination of T gel+DMPA is a promising new regimen in male contraception. The addition of the GnRH antagonist acyline, as part of an induction phase in a male contraception regimen, has limited clinical utility. Additional studies using T gel for male contraception are warranted.

Atherosclerosis is enhanced by testosterone deficiency and attenuated by CETP expression in transgenic mice

In this work, we investigated the impact of testosterone deficiency and cholesteryl ester transfer protein (CETP) expression on lipoprotein metabolism and diet-induced atherosclerosis. CETP transgenic mice and nontransgenic (nTg) littermates were studied 4 weeks after bilateral orchidectomy or sham operation. Castrated mice had an increase in the LDL fraction (+36% for CETP and +79% for nTg mice), whereas the HDL fraction was reduced (-30% for CETP and -11% for nTg mice). Castrated mice presented 1.7-fold higher titers of anti-oxidized LDL (Ox-LDL) antibodies than sham-operated controls. Plasma levels of CETP, lipoprotein lipase, and hepatic lipase were not changed by castration. Kinetic studies showed no differences in VLDL secretion rate, VLDL-LDL conversion rate, or number of LDL and HDL receptors. Competition experiments showed lower affinity of LDL from castrated mice for tissue receptors. Diet-induced atherosclerosis studies showed that testosterone deficiency increased by 100%, and CETP expression reduced by 44%, the size of aortic lesion area in castrated mice. In summary, testosterone deficiency increased plasma levels of apolipoprotein B-containing lipoproteins (apoB-LPs) and anti-OxLDL antibodies, decreased LDL receptor affinity, and doubled the size of diet-induced atherosclerotic lesions. The expression of CETP led to a milder increase of apoB-LPs and reduced atherosclerotic lesion size in testosterone-deficient mice.

The CAG Repeat Polymorphism in the Androgen Receptor Gene Is Associated with HDL-Cholesterol but Not with Coronary Atherosclerosis or Myocardial Infarction

Background: Age-adjusted morbidity and mortality rates from coronary heart disease (CHD) are higher in men than in women. Androgens are suspected to be responsible for the male disadvantage. The genomic effect of androgens is mediated by the androgen receptor (AR), which has a polymorphic CAG repeat in exon 1. The number of repeats is inversely related to the transcriptional activity of the AR on target genes.

Methods: We investigated the association of this CAG repeat polymorphism with CHD and myocardial infarction (MI) in 2 independent case–control studies involving 544 Caucasian men.

Results: The number of CAG repeats in the AR gene correlated significantly with HDL-cholesterol (HDL-C) in controls (r = 0.21; P = 0.015). This effect was independent of triglycerides, body mass index, alcohol intake, smoking, and age in a multiple regression model (R2 = 50%). Despite decreased HDL-C, lower CAG repeat numbers were not associated with increased risk for CHD (odds ratio = 0.82; 95% confidence interval, 0.50–1.36; P = 0.44) or MI in carriers of AR genes with lower CAG repeat numbers (odds ratio = 0.72; 95% confidence interval, 0.37–1.39; P = 0.33).

Conclusions: Shorter, more androgenic AR alleles with fewer CAG repeats are associated with lower HDL-C, but not with an increased risk for CHD or MI, which argues against a detrimental androgen effect on cardiovascular risk under physiologic conditions.