Sex hormone-binding globulin regulation of androgen bioactivity in vivo: validation of the free hormone hypothesis

High circulating concentrations of estradiol are anabolic for bone mass and strength in an adult male to female transgender mouse model

The effects of gender affirming hormone therapy (GAHT) on bone microarchitecture and fracture risk in adult transgender women is unclear. To investigate the concept that skeletal integrity and strength in trans women may be improved by treatment with a higher dose of GAHT than commonly prescribed, we treated adult male mice with a sustained, high dose of estradiol. Adult male mice at 16 weeks of age were administered ~1.3 mg estradiol by silastic implant, implanted intraperitoneally, for 12 weeks. Controls included vehicle treated intact females and males. High-dose estradiol treatment in males stimulated the endocortical deposition of bone at the femoral mid-diaphysis, increasing cortical thickness and bone area. This led to higher stiffness, maximum force, and the work required to fracture the bone compared to male controls, while post-yield displacement was unaffected. Assessment of the material properties of the bone showed an increase in both elastic modulus and ultimate stress in the estradiol treated males. Treatment of male mice with high dose estradiol was also anabolic for trabecular bone, markedly increasing trabecular bone volume, number and thickness in the distal metaphysis which was accompanied by an increase in the histomorphometric markers of bone remodelling, mineralizing surface/bone surface, bone formation rate and osteoclast number. In conclusion, a high dose of estradiol is anabolic for cortical and trabecular bone in a male to female transgender mouse model, increasing both stiffness and strength. These findings suggest that increasing the current dose of GAHT administered to trans women, while considering other potential adverse effects, may be beneficial to preserving their bone microstructure and strength.

Reference data on estrogen metabolome in healthy pregnancy

INTRODUCTION

Estrogen hormones and their metabolites are implicated in the maintenance of healthy pregnancy and adequate fetal development. Abnormal levels were related to increased risk of pregnancy complications, particularly preeclampsia. Our aims were (1) to develop a methodological platform for the comprehensive assessment of estrogen metabolome in pregnancy; (2) to collect healthy reference data for relevant elements of estrogen metabolome in each trimester; (3) to assess unconjugated fractions of the estrogen metabolome, (4) to assess the dominant metabolic pathways of estrogen compounds.

METHODS

We enrolled healthy pregnant mothers between gestational week 5-15 (on the confirmation of pregnancy; 79 samples), gestational weeks 19-27 (70 samples), and gestational week 34-39 (54 samples). A method employing liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed to assess estrone, 17-beta-estradiol, estriol levels, and their metabolites as conjugated and unconjugated forms. Descriptive statistics were used to characterize the level of compounds in each trimester.

RESULTS

Estrone, 17-beta-estradiol and estriol levels are dramatically increasing with the advancement of pregnancy. Measured levels were in a very wide range. 17-beta-estradiol is neither glucuronated nor sulphated. To the contrary, estriol and estrone are significantly conjugated; unconjugated fraction is <15% of total hormone levels in any trimester. Regarding metabolism, 4-methoxy-estradiol and 17-epiestriol were not detected.

CONCLUSION

We concluded that (1) the levels of estrogen compounds and metabolites increase with advancing gestational age; (2) the wide ranges of levels challenge the establishment of a healthy reference range for clinical purposes; (3) 17-beta-estradiol is not conjugated significantly; (4) 4-methylation and 17-epimerization pathways of estrogens are negligible with our LC-MS/MS method.

The Association Between SHBG and Osteoporosis: A NHANES Cross-Sectional Study and A Bidirectional Mendelian Randomization

This study aimed to examine the association between sex hormone-binding globulin (SHBG) and osteoporosis through a cross-sectional study and a two-sample bidirectional Mendelian randomization (MR). We used the National Health and Nutrition Examination Survey (NHANES) 2013-2014 and 2015-2016 data, with exposure as serum SHBG and outcome as osteoporosis and performed multivariate logistic regression to test the correlation between SHBG and osteoporosis. To determine the causal relationship between SHBG and osteoporosis, a two-sample bidirectional MR was employed. The genome-wide association study (GWAS) dataset for SHBG (n = 189,473) was obtained from the IEU database, and the GWAS dataset for osteoporosis (n = 212,778) was obtained from the FinnGen bioBank. The principal MR technique was inverse-variance weighting (IVW). In MR analyses, the MR-Egger intercept and Cochran Q test were used to detect multiple validity and horizontal heterogeneity. 1249 older adult participants (age ≥ 60) were involved in the cross-sectional study, including 113 osteoporosis cases. We identified a significant relationship between circulating SHBG concentration and osteoporosis risk [OR 3.963, 95% CI (2.095-7.495), P < 0.05]. Subgroup analysis indicated that SHBG was closely linked to the risk of osteoporosis in the female population [OR 1.008, 95% CI (1.002-1.013), P = 0.005] but not in males (P = 0.065). In addition, The IVW approach suggested a causal connection between SHBG and increased osteoporosis risk [OR 1.479, 95% CI (1.144-1.912), P = 0.003], and the MR-Egger intercept and the Cochran Q test validated the consistency of the MR results. Finally, the reverse MR analysis declined to identify a causal relation between SHBG and osteoporosis. Our research demonstrates a significant causal connection between circulating SHBG levels and increased osteoporosis risk. These results indicate that high SHBG may be associated with the risk of osteoporosis in postmenopausal women, but more research is needed.

Genetic correlations of alcohol consumption and alcohol use disorder with sex hormone levels in females and males

Background

Alcohol consumption behaviors and alcohol use disorder risk and presentation differ by sex, and these complex traits are associated with blood concentrations of the steroid sex hormones, testosterone and estradiol, and their regulatory binding proteins, sex hormone binding globulin (SHBG) and albumin. Genetic variation is associated with alcohol consumption and alcohol use disorder, as well as levels of steroid sex hormones and their binding proteins.

Methods

To assess the contribution of genetic factors to previously described phenotypic associations between alcohol-use traits and sex-hormone levels, we estimated genetic correlations (rg) using summary statistics from prior published, large sample size genome-wide association studies (GWAS) of alcohol consumption, alcohol dependence, testosterone, estradiol, SHBG, and albumin.

Results

For alcohol consumption, we observed positive genetic correlation (i.e. genetic effects in the same direction) with total testosterone in males (rg = 0.084, p = 0.007) and trends toward positive genetic correlation with bioavailable testosterone (rg = 0.060, p = 0.084) and SHBG in males (rg = 0.056, p = 0.086) and with albumin in a sex-combined cohort (rg = 0.082, p = 0.015); however in females, we observed positive genetic correlation with SHBG (rg = 0.089, p = 0.004) and a trend toward negative genetic correlation (i.e. genetic effects in opposite directions) with bioavailable testosterone (rg = -0.064, p = 0.032). For alcohol dependence, we observed a trend toward negative genetic correlation with total testosterone in females (rg = -0.106, p = 0.024) and positive genetic correlation with BMI-adjusted SHBG in males (rg = 0.119, p = 0.017). Several of these genetic correlations differed between females and males and were not in the same direction as the corresponding phenotypic associations.

Conclusions

Findings suggest that shared genetic effects may contribute to positive associations of alcohol consumption with albumin in both sexes, as well as positive associations between alcohol consumption and bioavailable testosterone and between alcohol dependence and SHBG in males. However, relative contributions of heritable and environmental factors to associations between alcohol-use traits and sex-hormone levels may differ by sex, with genetic factors contributing more in males and environmental factors contributing more in females.

The association of testosterone with sarcopenia and frailty in chronic liver disease

BACKGROUND

Testosterone is an important anabolic hormone responsible for maintaining body composition and muscle mass and circulates mostly albumin-bound, or sex hormone binding globulin (SHBG)-bound or free in the plasma. Of these fractions, the latter is bioactive and exerts the androgenic effects on male population. Liver cirrhosis, the advanced stage of any chronic liver disease characterized by permanent distortions to the hepatic architecture, disrupts the hypothalamic-pituitary-gonadal axis, leading to diminished levels of free testosterone and hypogonadism.

METHODS

We retrieved the PubMed database to provide a synopsis of testosterone's physiology and action and summarize the effect of sarcopenia in pre-cirrhotic and cirrhotic patients. Moreover, we scoped to provide insight into the relationship of testosterone levels with sarcopenia, frailty and survival in cirrhotic and non-cirrhotic population as well as to discuss the efficacy of exogenous testosterone supplementation on the anthropometric parameters and survival of those patients.

RESULTS

Low testosterone levels have been associated with sarcopenia, reduced body lean mass, decreased bone mineral density and frailty, thus leading to increased morbidity and mortality especially among cirrhotic patients. Furthermore, exogenous testosterone administration significantly ameliorated body composition on patients with chronic hepatic disease, without significant adverse effects. However, the current literature does not suggest any significant effect on survival of those patients. Moreover, the long-term safety of testosterone use remains an open question.

CONCLUSION

Low serum testosterone is strongly correlated with sarcopenia, frailty, higher rate of hepatic decompensation and mortality. Nonetheless, exogenous supplementation of testosterone did not ameliorate the liver-related outcomes and complications.

Fluctuating and Stable High Temperatures Differentially Affect Reproductive Endocrinology of Female Pupfish

For many fishes, reproductive function is thermally constrained such that exposure to temperatures above some upper threshold has detrimental effects on gametic development and maturation, spawning frequency, and mating behavior. Such impairment of reproductive performance at elevated temperatures involves changes to hypothalamic-pituitary-gonadal (HPG) axis signaling and diminished gonadal steroidogenesis. However, how HPG pathways respond to consistently high versus temporally elevated temperatures is not clear. Here, sexually mature Amargosa River Pupfish (Cyprinodon nevadensis amargosae) were maintained under thermal regimes of either stable ∼25°C (low temperature), diurnal cycling temperatures between ∼27 and 35°C (fluctuating temperature), or stable ∼35°C (high temperature) conditions for 50 days to examine effects of these conditions on HPG endocrine signaling components in the pituitary gland and gonad, ovarian and testicular gametogenesis status, and liver gene expression relating to oogenesis. Female pupfish maintained under stable high and fluctuating temperature treatments showed reduced gonadosomatic index values as well as a lower proportion of oocytes in the lipid droplet and vitellogenic stages. Females in both fluctuating and stable 35°C conditions exhibited reduced ovarian mRNAs for steroid acute regulatory protein (star), cholesterol side chain-cleavage enzyme, P450scc (cyp11a1), and 3β-hydroxysteroid dehydrogenase (3bhsd), while ovarian transcripts encoding 11β-hydroxysteroid dehydrogenase (11bhsd) and sex hormone-binding globulin (shbg) were elevated in females at constant 35°C only. Ovarian aromatase (cyp19a1a) mRNA levels were unaffected, but circulating 17β-estradiol (E2) was lower in females at 35°C compared to the fluctuating temperature condition. In the liver, mRNA levels for choriogenins and vitellogenin were downregulated in both the fluctuating and 35°C conditions, while hepatic estrogen receptor 2a (esr2a) and shbg mRNAs were elevated in 35°C females. Taken together, these results demonstrate the potential for elevated temperatures to impair ovarian steroidogenesis and reduce egg envelope and vitellogenin protein production in female C. n. amargosae pupfish, while also shedding light on how thermal regimes that only intermittently reach the upper thermal range for reproduction have differential impacts on reproductive endocrine pathways than constantly warm conditions.

Short-Term Clinical Assessment of Treating Female Androgenetic Alopecia with Autologous Stem Cells Derived from Human Hair Follicles

BACKGROUND

Androgenetic alopecia (AGA) is the most common form of alopecia, but treatment options are limited. This study evaluated clinical improvement in hair condition in women with AGA six months after a single injection of autologous cell micrografts (ACMs) containing hair follicle stem cells and dermal papilla cells.

METHODS

Twenty-three women with clinically and dermoscopy-confirmed AGA were included. Five 2.5 mm punch biopsies were taken from the skin of each patient with the Regenera device. The cell suspension was prepared with the Rigeneracons device and then injected into the hormone-dependent hairy zone of the scalp.

RESULTS

A significant improvement was observed on the visual analog scale (VAS) when comparing pre- and post-procedure photos (p < 0.001). The change in VAS scores was moderately negatively correlated with baseline ferritin concentration and positively with iron concentration. Improved outcomes were associated with higher baseline levels of sex hormone-binding globulin and 17α-hydroxyprogesterone. Neither testosterone nor DHT showed a significant correlation with VAS scores.

CONCLUSIONS

The ACM procedure was shown to be both safe and effective, yielding satisfying results six months after a single treatment session. Future investigations should aim to gather evidence that enables the development of a cost-effective approach while minimizing treatment burden and costs.

Endocrine and dog factors associated with semen quality

Knowledge of factors associated with semen quality may help in investigations of the aetiology and pathophysiology. We investigated the correlation between biomarkers for testicular cell function (anti-müllerian hormone, AMH, Inhibin B, testosterone, free androgen-index (testosterone/sex-hormone binding globulin), insulin like peptide 3, INSL-3), alkaline phosphate (ALP), canine prostate-specific esterase (CPSE), and heterophilic antibodies with dog variables, semen quality, and fertility. Blood and semen were collected from 65 Bernese Mountain Dogs. We evaluated total sperm count, motility and morphological parameters. The semen quality ranged from poor to excellent, with an average total sperm count of 1.1 × 109 and 50% morphologically normal spermatozoa (MNS). Age and abnormal testicular consistency correlated with decreased motility and MNS. Higher ALP correlated with higher total sperm count. AMH could not be detected in seminal plasma. AMH in blood correlated with head defects and high AMH concentration correlated with a severe decline in several semen parameters. Testosterone was negatively and CPSE positively correlated with age. No correlations were found for INSL-3, inhibin B, or heterophilic antibodies. Our findings contribute to the understanding of factors associated with semen quality in dogs, particularly related to Sertoli cell function.

The Utility of Preclinical Models in Understanding the Bone Health of Transgender Individuals Undergoing Gender-Affirming Hormone Therapy

PURPOSE OF REVIEW

To summarise the evidence regarding the effects of gender-affirming hormone therapy (GAHT) on bone health in transgender people, to identify key knowledge gaps and how these gaps can be addressed using preclinical rodent models.

RECENT FINDINGS

Sex hormones play a critical role in bone physiology, yet there is a paucity of research regarding the effects of GAHT on bone microstructure and fracture risk in transgender individuals. The controlled clinical studies required to yield fracture data are unethical to conduct making clinically translatable preclinical research of the utmost importance. Novel genetic and surgical preclinical models have yielded significant mechanistic insight into the roles of sex steroids on skeletal integrity. Preclinical models of GAHT have the potential inform clinical approaches to preserve skeletal integrity and prevent fractures in transgender people undergoing GAHT. This review highlights the key considerations required to ensure the information gained from preclinical models of GAHT are informative.

Testosterone Restores Body Composition, Bone Mass, and Bone Strength Following Early Puberty Suppression in a Mouse Model Mimicking the Clinical Strategy in Trans Boys

Transgender youth increasingly present at pediatric gender services. Some of them receive long-term puberty suppression with gonadotropin-releasing hormone analogues (GnRHa) before starting gender-affirming hormones (GAH). The impact of GnRHa use started in early puberty on bone composition and bone mass accrual is unexplored. It is furthermore unclear whether subsequent GAH fully restore GnRHa effects and whether the timing of GAH introduction matters. To answer these questions, we developed a mouse model mimicking the clinical strategy applied in trans boys. Prepubertal 4-week-old female mice were treated with GnRHa alone or with GnRHa supplemented with testosterone (T) from 6 weeks (early puberty) or 8 weeks (late puberty) onward. Outcomes were analyzed at 16 weeks and compared with untreated mice of both sexes. GnRHa markedly increased total body fat mass, decreased lean body mass, and had a modest negative impact on grip strength. Both early and late T administration shaped body composition to adult male levels, whereas grip strength was restored to female values. GnRHa-treated animals showed lower trabecular bone volume and reduced cortical bone mass and strength. These changes were reversed by T to female levels (cortical bone mass and strength) irrespective of the time of administration or even fully up to adult male control values (trabecular parameters) in case of earlier T start. The lower bone mass in GnRHa-treated mice was associated with increased bone marrow adiposity, also reversed by T. In conclusion, prolonged GnRHa use started in prepubertal female mice modifies body composition toward more fat and less lean mass and impairs bone mass acquisition and strength. Subsequent T administration counteracts GnRHa impact on these parameters, shaping body composition and trabecular parameters to male values while restoring cortical bone architecture and strength up to female but not male control levels. These findings could help guide clinical strategies in transgender care. © 2023 American Society for Bone and Mineral Research (ASBMR).

Controlled attenuation parameters to assess liver steatosis in obese patients with polycystic ovary syndrome

Objectives

This study was performed to investigate the changes and influencing factors of liver controlled attenuation parameter (CAP) in obese patients with polycystic ovary syndrome (PCOS), and to determine the prevalence and risk factors of nonalcoholic fatty liver disease (NAFLD) in PCOS patients with obesity.

Methods

Forty-one PCOS patients with obesity and twenty age- and body mass index (BMI)-matched control women without PCOS were enrolled in this study. General data, body composition, biochemical parameters, sex hormones, and liver CAP in the two groups were collected and compared. Liver CAP was measured using transient elastography.

Results

NAFLD was more common in the Obese PCOS group than in the control group (75.61% vs. 45.00%, P=0.018). Compared to the control group, the obese PCOS group showed apparent increases in alanine transaminase (ALT), aspartate transaminase (AST), CAP, triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), totle testosterone (TT), free androgen index (FAI), fasting insulin (FIns), and homeostasis model assessment-insulin resistance (HOMA-IR), along with lower high-density lipoprotein cholesterol (HDL-C) and sex hormone binding globulin (SHBG) levels. In addition, as shown by Spearman analysis, liver CAP in PCOS patients with obesity had a positive correlation with ALT, AST, TG, TT, FAI, FIns, and HOMA-IR, and a negative correlation with SHBG. Logistic regression analysis showed that TG, TT, FIns, and HOMA-IR were risk factors for NAFLD, while TT was an independent risk factor for NAFLD in PCOS patients with obesity.

Conclusion

PCOS patients with obesity had a significantly higher prevalence of NAFLD. Furthermore, in PCOS patients with obesity, liver CAP was associated with disorders of lipid metabolism, insulin resistance, and hyperandrogenemia, with elevated testosterone levels being an independent risk factor for NAFLD in PCOS patients with obesity.

The relationship between endometriosis and diet

Endometriosis is an oestrogen dependent, benign, chronic inflammatory disease characterised by ectopic endometrial implants. Current medical practices for the treatment of the disease are associated with several side effects over long periods, making the effect of diet on endometriosis an important aspect. To alleviate this need, we review related literature to identify the association between nutrients and endometriosis and to find the probable therapeutic effects of the nutrients and foods on endometriosis. Despite variations among the findings, several of the prior studies point to an inverse relationship between endometriosis and the consumption of fruits, vegetables, dairy products, and omega-3 fatty acids. Another common finding among the studies is the increased risk of endometriosis with higher consumption of trans-unsaturated fatty acids and red meat. Due to the limited size of the samples in existing literature, however, significance of the association between diet and endometriosis is not conclusive. Further research is needed to better identify the role of diet on endometriosis.

Effect of Selenium Supplementation on Biochemical Markers of Women with Polycystic Ovarian Syndrome: A Systematic Review

Polycystic ovary syndrome (PCOS) is a widespread endocrine disorder among fertile women and may be induced by nutritional deficiencies. In this study, we assess the impact of selenium supplementation (SS) on biochemical markers in women with PCOS. To gather relevant literature, we searched the Web of Science, Cochrane Library, Scopus, Embase, and MEDLINE databases from inception up to July 24, 2022. Subsequently, we included all published full-text randomized clinical trials examining the effects of SS versus placebo on biochemical changes in women with PCOS. Review Manager 5.3 was used to collect and analyze data and assess the risk of bias. Seven articles, comprising 413 women, were ultimately involved in the study. According to the results, SS could increase the level of quantitative insulin sensitivity check index [standardized mean difference (SMD)=0.34, 95% confidence interval (CI)=0.04∼0.65], total antioxidant capacity (SMD=0.89 mmol/L, 95% CI=0.52∼1.26), and glutathione (SMD=1.00 μmol/L, 95% CI=0.22∼1.78). Conversely, SS could decrease triglyceride, cholesterol, fasting plasma glucose, insulin, and the homeostasis model of assessment-insulin resistance levels compared with the placebo. Furthermore, there were no significant differences regarding sex hormone-binding globulin level, testosterone level, malondialdehyde, and body mass index between the two groups. In addition, the results suggest that SS improves biochemical markers in women with PCOS and thus is recommended for treating biochemical disorders among these women in addition to standard treatment.

Androgen signalling in the ovaries and endometrium

Currently, our understanding of hormonal regulation within the female reproductive system is largely based on our knowledge of estrogen and progesterone signalling. However, while the important functions of androgens in male physiology are well known, it is also recognized that androgens play critical roles in the female reproductive system. Further, androgen signalling is altered in a variety of gynaecological conditions, including endometriosis and polycystic ovary syndrome, indicative of regulatory roles in endometrial and ovarian function. Co-regulatory mechanisms exist between different androgens, estrogens, and progesterone, resulting in a complex network of steroid hormone interactions. Evidence from animal knockout studies, in vitro experiments, and human data indicate that androgen receptor expression is cell-specific and menstrual cycle stage-dependent, with important regulatory roles in the menstrual cycle, endometrial biology, and follicular development in the ovaries. This review will discuss the expression and co-regulatory interactions of androgen receptors, highlighting the complexity of the androgen signalling pathway in the endometrium and ovaries, and the synthesis of androgens from additional alternative pathways previously disregarded as male-specific. Moreover, it will illustrate the challenges faced when studying androgens in female biology, and the need for a more in-depth, integrative view of androgen metabolism and signalling in the female reproductive system.

Nigella sativa-Floral Honey and Multi-Floral Honey versus Nigella sativa Oil against Testicular Degeneration Rat Model: The Possible Protective Mechanisms

The male reproductive function, particularly the testes, and the related hormones are sensitive to various xenobiotics. This work aimed for the first time to assess Nigella sativa floral honey (NS floral honey) and multi-floral honey (M-floral honey) versus Nigella sativa oil (NS oil) against rat testicular degeneration induced with azathioprine (AZA). A total of 40 male Wister rats were assigned into 5 groups: (1) control, (2) 15 mg/kg of AZA, (3) AZA + 1.4 mL/kg of M-floral honey, (4) AZA + 1.4 mL/kg of NS floral honey, and (5) AZA + 500 mg/kg of NA oil. Total testosterone (TT), free testosterone (FT), free androgen index (FAI), gonadotrophins, sex-hormone-binding globulin (SHBG), apoptosis markers, and redox status were assessed to clarify the possible protective mechanisms. Pituitary–testicular axis disruption, apoptosis markers, poor redox status, and sperm quality (count, viability, and motility) were set with AZA. Serum TT, SHBG, and absolute and relative testis weight were significantly restored in the NS oil and NS floral honey groups. Meanwhile, the NS oil group exhibited a significant elevation in FT and FAI. Serum gonadotrophins increased significantly in the NS floral honey (p < 0.01) and M-floral honey and NS oil (p < 0.05) groups. Testicular caspase-3, caspase-9, and nitric oxide showed significant improvement in the NS floral honey and NS oil groups. NS oil supplementation significantly normalized redox status (p < 0.05), whereas NS floral honey improved malondialdehyde and superoxide dismutase activity. Sperm quality exhibited a significant improvement in the NS oil group (p < 0.05). M-floral honey did not show reliable results. Although NS floral honey could protect against testicular damage, it did not upgrade to the level of improvement achieved with NS oil. We claim that further clinical studies are essential for focusing on the quality and quantity of bioactive constituents.

Associations of sex-related steroid hormones and proteins with alcohol dependence: A United Kingdom Biobank study

BACKGROUND

Sex-related steroid hormones and proteins may contribute to the sex differences in the characteristics and health consequences of alcohol use disorder. This study aimed to examine the associations between alcohol dependence (AD) and sex-related hormones/proteins using a population-based dataset.

METHODS

We retrieved serum total testosterone (TT) and estradiol (TE2), sex hormone binding globulin (SHBG), and albumin levels along with clinical data from the UK Biobank. Hormone/protein levels were compared between AD (lifetime AD and/or related diagnoses; 2218 males; 682 females) and control (no aforementioned diagnoses and AUDIT<8; 198,058 males; 250,830 females) groups with sex-dependent linear regression models adjusting for age and body mass index. Moderation and mediation analyses were performed to test whether SHBG was a moderator and/or mediator between hormones and AD or current drinking.

RESULTS

AD males had higher TT, TE2, and SHBG levels but lower bioavailable testosterone, bioavailable estradiol, and albumin levels than controls (padjusted<0.001). After adjusting for menopause, AD females had higher TT and lower albumin levels than controls (padjusted<0.001). These differences remained after accounting for current drinking frequency (p < 0.001). SHBG moderated TT's effect on AD in males (pinteraction<0.001). SHBG was a positive mediator between TT and AD in both sexes and between TE2 and AD in males (p < 0.001), but a negative mediator between TT and current drinking in controls (both sexes) and AD males (p < 0.001).

CONCLUSIONS

Testosterone and estradiol levels are altered in males and females with AD distinctly regardless of current drinking frequency. SHBG may play a critical role in these associations.

Age, weight and circulating concentrations of total testosterone are associated with the relative prostatic size in adult intact male dogs

Prostatic hyperplasia (PH) is an androgen-dependent condition associated with increased prostatic size that is common in intact dogs, and similar to the condition in men. In dogs, the increase in prostatic size is most prominent the first years, and after approximately four years (in beagles), a plateau is reached, and further growth is slower. Why the prostate continues to grow more in some individuals is not clear. Most testosterone in the circulation is bound to albumin or sex hormone binding globulin (SHBG) and only a minor part is unbound and biologically active. The binding to SHBG has higher affinity than that to albumin. In addition, SHBG has own biological functions, modifying testosterone action. The aim of the present study was to investigate if there is an association between relative prostatic size and the variables total testosterone concentration, SHBG concentration, an estimation of bioavailable testosterone: the ratio between testosterone and SHBG (free androgen index, FAI), estradiol concentration, the estradiol/testosterone ratio, dog age and dog weight. Hormone concentrations were measured in serum from 79 intact male dogs aged ≥ four years, weighing ≥ five kg. The size of the prostate was estimated using ultrasonography, and relative prostate size, S_rel, was calculated as the estimated size related to the normal size for a 4-year-old dog of the same weight. There as a negative correlation between testosterone concentration and age (ρ = -0.27, P = 0.018) and a positive correlation between age and S_rel (ρ = 0.27, P = 0.016) and between SHBG and weight (ρ = 0.38, P = 0.001). The FAI was negatively correlated with dog weight (ρ = -0.32, P = 0.004). There were no significant correlations between S_rel and SHBG or FAI or between estradiol or estradiol/testosterone and S_rel, age or weight. A multiple regression analysis showed significant associations between log S_rel and log testosterone concentration, log age and log weight of the dog, with an adjusted R² of 9.5%. Although the variables total testosterone concentration, age and weight of the dog were all significantly associated with S_rel, the coefficient of determination was low, indicating that they only explained a minor part of the prostatic size. The results support the analysis of total testosterone in studies of prostatic growth in the dog.

Integrated Computational Approaches for Inhibiting Sex Hormone-Binding Globulin in Male Infertility by Screening Potent Phytochemicals

Male infertility is significantly influenced by the plasma-protein sex hormone-binding globulin (SHBG). Male infertility, erectile dysfunction, prostate cancer, and several other male reproductive system diseases are all caused by reduced testosterone bioavailability due to its binding to SHBG. In this study, we have identified 345 phytochemicals from 200 literature reviews that potentially inhibit severe acute respiratory syndrome coronavirus 2. Only a few studies have been done using the SARS-CoV-2 inhibitors to identify the SHBG inhibitor, which is thought to be the main protein responsible for male infertility. In virtual-screening and molecular-docking experiments, cryptomisrine, dorsilurin E, and isoiguesterin were identified as potential SHBG inhibitors with binding affinities of -9.2, -9.0, and -8.8 kcal/mol, respectively. They were also found to have higher binding affinities than the control drug anastrozole (-7.0 kcal/mol). In addition to favorable pharmacological properties, these top three phytochemicals showed no adverse effects in pharmacokinetic evaluations. Several molecular dynamics simulation profiles' root-mean-square deviation, radius of gyration, root-mean-square fluctuation, hydrogen bonds, and solvent-accessible surface area supported the top three protein-ligand complexes' better firmness and stability than the control drug throughout the 100 ns simulation period. These combinatorial drug-design approaches indicate that these three phytochemicals could be developed as potential drugs to treat male infertility.

Chronic liver diseases and erectile dysfunction

Chronic liver diseases (CLDs) are characterized by progressive necrosis of hepatocytes, which leads to liver fibrosis and cirrhosis, and ultimately liver dysfunction. The statistics of 2020 shows that the number of patients with CLDs, including chronic hepatitis, fatty liver, and cirrhosis, may exceed 447 million in China. The liver is a crucial organ for the metabolism of various substances, including sex hormones and lipids. CLDs frequently result in abnormalities in the metabolism of sex hormones, glucose, and lipids, as well as mental and psychological illnesses, all of which are significant risk factors for erectile dysfunction (ED). It has been reported that the prevalence of ED in male patients with CLDs ranges from 24.6 to 85.0%. According to a survey of Caucasians, liver transplantation may improve the erectile function of CLDs patients with ED. This finding supports the link between CLDs and ED. In addition, ED is often a precursor to a variety of chronic diseases. Given this correlation and the significant prevalence of CLDs, it is important to evaluate the epidemiology, risk factors, etiology, and treatment outcomes of ED in male patients with CLDs, expecting to attract widespread attention.

Oral contraceptives in the central nervous system: Basic pharmacology, methodological considerations, and current state of the field

Millions of women around the world use combined oral contraceptives (OCs), yet surprisingly little is known about their central nervous system (CNS) effects. This article provides a short overview of the basic pharmacology of OCs, emphasizing features that may be relevant to understanding their effects in the CNS. Historical and recent findings from studies of cognitive function, mood, and negative affect (depressive changes under OC use) are then reviewed. We also present data from an archival dataset from our own laboratory in which we explore dysphoric changes in women using four generations of contraceptive progestins. Current data in the field are consistent with a modest effect of OC use on CNS variables, but conclusions based on current findings must be made very cautiously because of multiple methodological issues in many published studies to date, and inconsistencies in the findings. Directions for future research over the next 10 years are suggested. (150 words).

Male sex hormones, aging, and inflammation

Adequate levels of androgens (eugonadism), and specifically testosterone, are vital compounds for male quality of life, longevity, and positive health outcomes. Testosterone exerts its effects by binding to the androgen receptor, which is expressed in numerous tissues throughout the body. Significant research has been conducted on the impact of this steroid hormone on skeletal, muscle and adipose tissues and on the cardiovascular, immune, and nervous systems. Testosterone levels have also been studied in relation to the impact of diseases, aging, nutrition and the environment on its circulating levels. Conversely, the impact of testosterone on health has also been evaluated with respect to its cardiac and vascular protective effects, body composition, autoimmunity and all-cause mortality. The male aging process results in decreasing testosterone levels over time. The exact mechanisms and impact of these changes in testosterone levels with age on health- and life-span are still not completely clear. Further research is needed to determine the optimal testosterone and androgen levels to protect from chronic age-related conditions such as frailty and osteoporosis.

Reference intervals for free testosterone in adult men measured using a standardized equilibrium dialysis procedure

BACKGROUND

Free testosterone (FT) determination may be helpful in evaluating men suspected of testosterone deficiency especially in conditions with altered binding-protein concentrations. However, methods for measuring FT by equilibrium dialysis and reference intervals vary among laboratories.

OBJECTIVE

To determine reference intervals for FT in healthy, nonobese men by age groups as well as in healthy young men, 19-39 years, using a standardized equilibrium dialysis procedure METHODS: We measured FT in 145 healthy, nonobese men, 19 years or older, using a standardized equilibrium dialysis method performed for 16-h at 37°C using undiluted serum and dialysis buffer that mimicked the ionic composition of human plasma. FT in dialysate was measured using a CDC-certified liquid chromatography tandem mass spectrometry assay.

RESULTS

In healthy nonobese men, the 2.5th, 10th, 50th, 90th, and 97.5th percentile values for FT were 66, 91, 141, 240, and 309 pg/ml, respectively; corresponding values for men, 19-39 years, were 120, 128, 190, 274, and 368 pg/ml, respectively. FT levels by age groups exhibit the expected age-related decline. FT levels were negatively associated with body mass index, age, and sex hormone-binding globulin (SHBG) levels. Percent FT was lower in middle-aged and older men than young men adjusting for SHBG level.

DISCUSSION

Further studies are needed to determine how these reference intervals apply to the diagnosis of androgen deficiency in clinical populations and in men of different races and ethnicities in different geographic regions.

CONCLUSION

Reference intervals for free FT levels (normative range 66-309 pg/ml [229-1072 pmol/L] in all men and 120-368 pg/ml [415-1274 pmol/L] in men, 19-39 years), measured using a standardized equilibrium dialysis method in healthy nonobese men, provide a rational basis for categorizing FT levels. These intervals require further validation in other populations, in relation to outcomes, and in randomized trials.

Primary, secondary and compensated male biochemical hypogonadism in people living with HIV (PLWH): relevance of sex hormone-binding globulin (SHBG) measurement and comparison between liquid chromatography-tandem mass spectrometry (LC-MS/MS) and chemiluminescent immunoassay for sex steroids assay

BACKGROUND

Data about classification of hypogonadism and estrogen deficiency in male people living with HIV (PLWH) are scanty.

AIM

To investigate the prevalence and characterization of biochemical hypogonadism and relative estrogen deficiency in male PLWH aged < 50 comparing liquid chromatography-tandem mass spectrometry (LC-MS/MS) with chemiluminescent immunoassay (CI), and combining gonadotropin, sex hormone-binding globulin (SHBG) and serum estradiol (E2) measurements.

METHODS

Prospective, cross-sectional, observational study. Serum total testosterone (TT), E2, gonadotropins, SHBG were measured by CI. TT and E2 were also assessed by LC-MS/MS. Free testosterone (cFT) was calculated by Vermeulen equation.

RESULTS

A total of 316 PLWH (45.3 ± 5.3 years) were enrolled. TT and cFT by LC-MS/MS were lower compared to CI (p < 0.0001). The prevalence of biochemical hypogonadism was higher with LC-MS/MS than CI, both for TT (5.1% vs 3.2%, p < 0.0001) or cFT (9.5% vs 7%, p < 0.0001). The prevalence of hypogonadism (overt + compensated) was 17.1% for cFT using LC-MS/MS. Secondary form of hypogonadism was more prevalent than primary. The prevalence of relative estrogen deficiency was of 30.0% among hypogonadal patients and 15.5% among eugonadal.

CONCLUSIONS

The prevalence of male hypogonadism results underestimated by CI compared to LC-MS/MS in PLWH, both for TT and cFT. SHBG and gonadotropins are essential for detecting T deficiency.

Diagnosis of hypogonadism in ageing men

To make the diagnosis of hypogonadism in an ageing man, in absence of rare organic cause often referred to as functional or late onset hypogonadism (LOH), he should present with a clinical syndrome suggestive of androgen deficiency and have consistently low serum testosterone (T) levels. This does not differ from the diagnosis of any other form of hypogonadism. Particular to LOH diagnostic are uncertainties surrounding this entity: signs and symptoms of androgen deficiency (including sexual symptoms) are nonspecific in older men; clinical significance of only moderately low T levels is uncertain; comorbidity plays a substantial role with potential for reversibility; the place of T therapy in these men is debatable. This context demands for a pragmatic, but appropriately conservative approach to diagnosis. Evaluation should be stepwise with clinical evaluation, if suggestive for androgen deficiency, followed by measurement of a fasting morning serum T, if unequivocally low to be confirmed in a separate morning sample by a second low T or, if initial T borderline low or in presence of factors known to affect SHBG, by a low calculated free T level. All other (free) T results make hypogonadism an unlikely cause of the patient's symptoms. In the absence of consensus cut-off levels for total and free T in the published clinical guidelines for diagnosis of hypogonadism, it seems appropriate in the context of LOH to use stringent criteria indicating a convincingly low serum T. The approach to the diagnosis of LOH is not fundamentally different from that of other forms of hypogonadism but should put extra weight on prioritizing the shunning of overdiagnosis above the risk of underdiagnosis.

Preterm infant circulating sex steroid levels are not altered by transfusion with adult male plasma: a retrospective multicentre cohort study

OBJECTIVE

To determine if plasma transfusions with male donor plasma to very preterm infants affect circulatory levels of sex steroids.

DESIGN AND PATIENTS

Retrospective multicentre cohort study in 19 infants born at gestational age <29 weeks requiring plasma transfusion during their first week of life.

SETTING

Three neonatal intensive care units in Sweden.

MAIN OUTCOME MEASURES

Concentrations of sex steroids and sex hormone-binding globulin (SHBG) in donor plasma and infant plasma measured before and after a plasma transfusion and at 6, 12, 24 and 72 hours.

RESULTS

The concentrations of progesterone, dehydroepiandrosterone and androstenedione were significantly lower in donor plasma than in infant plasma before the transfusion (median (Q1-Q3) 37.0 (37.0-37.0), 1918 (1325-2408) and 424 (303-534) vs 901 (599-1774), 4119 (2801-14 645) and 842 (443-1684) pg/mL), while oestrone and oestradiol were higher in donor plasma (17.4 (10.4-20.1) and 16.0 (11.7-17.2) vs 3.1 (1.1-10.2) and 0.25 (0.25-0.25) pg/mL). Median testosterone and dihydrotestosterone (DHT) levels were 116-fold and 21-fold higher in donor plasma than pre-transfusion levels in female infants, whereas the corresponding difference was not present in male infants. Plasma sex steroid levels were unchanged after completed transfusion compared with pre-transfusion levels, irrespective of the gender of the receiving infant. The SHBG concentration was significantly higher in donor than in recipient plasma (22.8 (17.1-33.5) vs 10.2 (9.1-12.3) nmol/L) before transfusion but did not change in the infants after the transfusion.

CONCLUSIONS

A single transfusion of adult male plasma to preterm infants had no impact on circulating sex steroid levels.

Dehydroepiandrosterone Supplementation Results in Varying Tissue-specific Levels of Dihydrotestosterone in Male Mice

Dehydroepiandrosterone (DHEA), an adrenal androgen precursor, can be metabolized in target tissues into active sex steroids. It has been proposed that DHEA supplementation might result in restoration of physiological local sex steroid levels, but knowledge on the effect of DHEA treatment on local sex steroid levels in multiple tissues is lacking. To determine the effects of DHEA on tissue-specific levels of sex steroids, we treated orchiectomized (ORX) male mice with DHEA for 3 weeks and compared them with vehicle-treated ORX mice and gonadal intact mice. Intra-tissue levels of sex steroids were analyzed in reproductive organs (seminal vesicles, prostate, m. levator ani), major body compartments (white adipose tissue, skeletal muscle, and brain), adrenals, liver, and serum using a sensitive and validated gas chromatography-mass spectrometry method. DHEA treatment restored levels of both testosterone (T) and dihydrotestosterone (DHT) to approximately physiological levels in male reproductive organs. In contrast, this treatment did not increase DHT levels in skeletal muscle or brain. In the liver, DHEA treatment substantially increased levels of T (at least 4-fold) and DHT (+536%, P < 0.01) compared with vehicle-treated ORX mice. In conclusion, we provide a comprehensive map of the effect of DHEA treatment on intra-tissue sex steroid levels in ORX mice with a restoration of physiological levels of androgens in male reproductive organs while DHT levels were not restored in the skeletal muscle or brain. This, and the unexpected supraphysiological androgen levels in the liver, may be a cause for concern considering the uncontrolled use of DHEA.

Role of sex hormone-binding globulin in the free hormone hypothesis and the relevance of free testosterone in androgen physiology

According to the free hormone hypothesis, biological activity of a certain hormone is best reflected by free rather than total hormone concentrations. A crucial element in this theory is the presence of binding proteins, which function as gatekeepers for steroid action. For testosterone, tissue exposure is governed by a delicate equilibrium between free and total testosterone which is determined through interaction with the binding proteins sex hormone-binding globulin and albumin. Ageing, genetics and various pathological conditions influence this equilibrium, hereby possibly modulating hormonal exposure to the target tissues. Despite ongoing controversy on the subject, strong evidence from recent in vitro, in vivo and human experiments emphasizes the relevance of free testosterone. Currently, however, clinical possibilities for free hormone diagnostics are limited. Direct immunoassays are inaccurate, while gold standard liquid chromatography with tandem mass spectrometry (LC-MS/MS) coupled equilibrium dialysis is not available for clinical routine. Calculation models for free testosterone, despite intrinsic limitations, provide a suitable alternative, of which the Vermeulen calculator is currently the preferred method. Calculated free testosterone is indeed associated with bone health, frailty and other clinical endpoints. Moreover, the added value of free testosterone in the clinical diagnosis of male hypogonadism is clearly evident. In suspected hypogonadal men in whom borderline low total testosterone and/or altered sex hormone-binding globulin levels are detected, the determination of free testosterone avoids under- and overdiagnosis, facilitating adequate prescription of hormonal replacement therapy. As such, free testosterone should be integrated as a standard biochemical parameter, on top of total testosterone, in the diagnostic workflow of male hypogonadism.

Modeling hormonal contraception in female rats: A framework for studies in behavioral neurobiology

Research on hormonal contraceptives (HC) in animal models is lacking, and as a result, so is our understanding of the impact of HC on the brain and behavior. Here, we provide a review of the pharmacology of HC, as well as the methodology and best practices for designing a model of HC in female rats. We outline specific methodological considerations regarding dosing, route of administration, exposure time/timing, and selecting a control group. We also provide a framework outlining important levels of analysis for thinking about the impact of HC on behavioral and neurobiological outcomes. The purpose of this review is to equip researchers with foundational knowledge, and some basic elements of experimental design for future studies investigating the impact of HC on the brain and behavior of female rats.

A Shifting Relationship Between Sex Hormone-Binding Globulin and Total Testosterone Across Puberty in Boys

CONTEXT

Sex hormone-binding globulin (SHBG) is associated with levels of total testosterone (total-T), and both total-T and SHBG are associated with obesity.

OBJECTIVE

We aimed to clarify the nature of the relationship between testosterone and SHBG and improve our understanding of their relationships with obesity. We hypothesize that the hypothalamic-pituitary-gonadal axis contributes to the homeostasis of testosterone by increasing the production of gonadal testosterone through a feedback mechanism that might operate differently at different pubertal stages.

METHODS

We investigated the dynamics of the relationship between SHBG, total-T, and body mass index (BMI) throughout puberty (from age 9 to 17) using longitudinal data obtained in 507 males. The directionality of this relationship was explored using polygenic scores of SHBG and total-T, and a two-sample Mendelian Randomization (MR) in male adults.

RESULTS

Consistent with our hypothesis, we found positive relationships between SHBG and total-T at age 15 and 17 but either no relationship or a negative relationship during the earlier time points. Such shifting relationships explained age-related changes in the association between total-T and BMI. Polygenic scores of SHBG and total-T in mediation analyses and the two-sample MR in male adults suggested an effect of SHBG on total-T but also a somewhat weaker effect of total-T on SHBG. Two-sample MR also showed an effect of BMI on SHBG but no effect of SHBG on BMI.

CONCLUSION

These results clarify the nature of the relationship between testosterone and SHBG during puberty and adulthood and shed new light on their possible relationship with obesity.

Interaction between mono-(2-ethylhexyl) phthalate and retinoic acid alters Sertoli cell development during fetal mouse testis cord morphogenesis

Phthalic acid esters (phthalates) are a class of industrial chemicals that cause developmental and reproductive toxicity, but there are significant gaps in knowledge of phthalate toxicity mechanisms. There is evidence that phthalates disrupt retinoic acid signaling in the fetal testis, potentially disrupting control of spatial and temporal patterns of testis development. Our goal was to determine how a phthalate would interact with retinoic acid signaling during fetal mouse testis development. We hypothesized that mono-(2-ethylhexyl) phthalate (MEHP) would exacerbate the adverse effect of all-trans retinoic acid (ATRA) on seminiferous cord development in the mouse fetal testis. To test this hypothesis, gestational day (GD) 14 C57BL/6 mouse testes were isolated and cultured on media containing MEHP, ATRA, or a combination of both compounds. Cultured testes were collected for global transcriptome analysis after one day in culture and for histology and immunofluorescent analysis of Sertoli cell differentiation after three days in culture. ATRA disrupted seminiferous cord morphogenesis and induced aberrant FOXL2 expression. MEHP alone had no significant effect on cord development, but combined exposure to MEHP and ATRA increased the number of FOXL2-positive cells, reduced seminiferous cord number, and increased testosterone levels, beyond the effect of ATRA alone. In RNA-seq analysis, ATRA treatment and MEHP treatment resulted in differential expression of genes 510 and 134 genes, respectively, including 70 common differentially expressed genes (DEGs) between the two treatments, including genes with known roles in fetal testis development. MEHP DEGs included RAR target genes, genes involved in angiogenesis, and developmental patterning genes, including members of the homeobox superfamily. These results support the hypothesis that MEHP modulates retinoic acid signaling in the mouse fetal testis and provide insight into potential mechanisms by which phthalates disrupt seminiferous cord morphogenesis.

N/C Interactions Are Dispensable for Normal In Vivo Functioning of the Androgen Receptor in Male Mice

The androgen receptor (AR) plays a central role in the development and maintenance of the male phenotype. The binding of androgens to the receptor induces interactions between the carboxyterminal ligand-binding domain and the highly conserved 23FQNLF27 motif in the aminoterminal domain. The role of these so-called N/C interactions in AR functioning is debated. In vitro assays show that mutating the AR in the 23FQNLF27 motif (called ARNoC) attenuates the AR transactivation of reporter genes, has no effect on ligand binding, but does affect protein-protein interactions with several AR coregulators. To test the in vivo relevance of the N/C interaction, we analyzed the consequences of the genomic introduction of the ARNoC mutation in mice. Surprisingly, the ARNoC/Y mice show a normal male development, with unaffected male anogenital distance and normal accessory sex glands, male circulating androgen levels, body composition, and fertility. The responsiveness of androgen target genes in kidney, prostate, and testes was also unaffected. We thus conclude that the N/C interactions in the AR are not essential for the development of a male phenotype under normal physiological conditions.

Differential Changes in Circulating Steroid Hormones in Hibernating Brown Bears: Preliminary Conclusions and Caveats

Brown bears are obese when they enter the den, and after 6 mo of hibernation and physical inactivity, bears show none of the adverse consequences of a sedentary lifestyle in humans, such as cardiovascular disease, type 2 diabetes, and kidney failure. The metabolic mechanisms that drive hibernation physiology in bears are poorly defined, but systemic endocrine regulators are likely involved. To investigate the potential role of steroid hormones, we quantified the total levels of 12 steroid hormones, the precursor cholesterol, sex hormone-binding globulin (SHBG), and corticosterone-binding globulin (CBG) in paired serum samples from subadult free-ranging Scandinavian brown bears during the active and hibernation states. During hibernation, androstenedione and testosterone were significantly decreased in subadult female bears (n=13), whereas they increased in all males but one (n=6) and therefore did not reach a significant difference. Despite this difference, SHBG increased more than 20-fold during hibernation for all bears. Compared with SHBG concentrations in humans, bear levels were very low in the active state, but during hibernation, levels equaled high levels in humans. The increased SHBG levels likely maintain a state of relative quiescence of the reproductive hormones in hibernating bears. Interestingly, the combination of SHBG and testosterone levels results in similar free bioavailable testosterone levels of 70-80 pM in both subadult and adult sexually active male bears, suggesting a role for SHBG in controlling androgen action during hibernation in males. Dehydroepiandrosterone sulfate, dihydrotestosterone, and estradiol levels were below the detection limit in all but one animal. The metabolically active glucocorticoids were significantly higher in both sexes during hibernation, whereas the inactive metabolite cortisone was reduced and CBG was low approaching the detection limit. A potential caveat is that the glucocorticoid levels might be affected by the ketamine applied in the anesthetic mixture for hibernating bears. However, increased hibernating cortisol levels have consistently been reported in both black bears and brown bears. Thus, we suggest that high glucocorticoid activity may support the hibernation state, likely serving to promote lipolysis and gluconeogenesis while limiting tissue glucose uptake to maintain a continuous glucose supply to the brain.

The association between serum sex hormone-binding globulin changes during progestin-primed ovarian stimulation and embryo outcomes: a retrospective cohort study

Objective: This study is aimed to examine the associations between embryo outcomes and serum sex hormone-binding globulin (SHBG) changes during progestin-primed ovarian stimulation (PPOS) protocols in IVF/ICSI cycles.Research methods: This study included 2790 eligible consecutive cycles of patients aged 21-53 years undergoing PPOS treatment. Multivariable linear regression analysis was performed to explore the association between SHBG changes and embryo outcomes.Results of the study: Our results showed that the SHBG-increase rate on the HCG day and in the late follicular phase were positively and linearly correlated with available embryos in day3, with adjusted regression coefficients (β) for the SHBG-increase rate on the HCG day, in the late follicular phase were 0.6 (0.4, 0.9), 0.4 (0.2, 0.6), but in the middle follicular phase and in the early follicular phase, this correlation was not significant (p > 0.05).Conclusion: Our results indicate that serum SHBG increment may serve as a biomarker of the developmental potential of the oocytes from patients undergoing the PPOS protocol.

The Effect of a Combination of Eucommia ulmoides and Achyranthes japonica on Alleviation of Testosterone Deficiency in Aged Rat Models

With aging, men inevitably encounter irreversible changes, including progressive loss of testosterone and physical strength, and increased fat mass. To assess the alleviatory effects of EUAJ on andropause symptoms, including in vivo testosterone deficiency, we administered EUAJ for 6 weeks in 22-week-old Sprague-Dawley rats. Before EUAJ (3:1) (E. ulmoides:A. japonica = 3:1, KGC08EA) administration, testosterone decline in 22-week-old SD rats was confirmed compared to 7-week-old SD rats (NC group). After administration of EUAJ (3:1) at 20, 40, and 80 mg/kg for 6 weeks, testosterone, free testosterone, and mRNA expression levels (Cyp11a1 and Hsd3b1) were significantly increased at 40 mg/kg EUAJ (3:1), whereas mRNA expression levels of Cyp19a1 and Srd5a2 were significantly reduced at this concentration, compared to the control group. Swimming retention time was significantly increased at both 40 mg/kg and 80 mg/kg. In summary, EUAJ (3:1) enhanced testosterone production by increasing bioavailable testosterone, sex hormone-binding globulin (SHBG), and enzymes related to testosterone synthesis at 40 mg/kg. In addition, 80 mg/kg EUAJ (3:1) also increased physical and testicular functions.

Accurate measurement of total and free testosterone levels for the diagnosis of androgen disorders

The circulating concentrations of total and free testosterone vary substantially in people over time due to biologic factors as well as due to measurement variation. Accurate measurement of total and free testosterone is essential for making the diagnosis of androgen disorders. Total testosterone should ideally be measured in a fasting state in the morning using a reliable assay, such as liquid chromatography tandem mass spectrometry, in a laboratory that is certified by an accuracy-based benchmark. Free testosterone levels should be measured in men in whom alterations in binding protein concentrations are suspected or in whom total testosterone levels are only slightly above or slightly below the lower limit of the normal male range for testosterone.

Sex hormone binding globulin as a potential drug candidate for liver-related metabolic disorders treatment

Sex hormone binding globulin (SHBG) is a hepatokine that binds to circulating steroid hormones (testosterone, oestradiol) to regulate their concentration in the bloodstream. Recently SHBG was recognized as an essential biomarker for metabolic syndrome (MetS) and hepatic steatosis development. At the hepatic level, the production of SHBG is mainly regulated by sex steroids and thyroxine. Studies of various research groups, including ours, showed that SHBG could be considered a reliable marker of insulin resistance and, therefore, can serve as a predictor of type 2 diabetes. Moreover, increased levels of circulating pro-inflammatory mediators strongly correlate with lowered serum levels of SHBG. This review paper emphasizes the role of SHBG as a potential drug candidate in the course of various metabolic dysfunctions, including non-alcoholic fatty liver disease (NAFLD), obesity, diabetes mellitus and insulin resistance. The studies related to SHBG and its role in the course of metabolic disorders are very limited. Here, we have summarized the most current knowledge about SHBG and its mechanism of action, indicating a novel concept for its possible therapeutic application in the management framework of commonly occurring metabolic dysfunctions.

SHBG, Bone Mineral Density, and Physical Function Among Injection Drug Users With and Without HIV and HCV

CONTEXT

Sex hormone-binding globulin (SHBG) is a glycoprotein that regulates the bioavailability of sex hormones and is higher in people with HIV (PWH) and hepatitis C virus (HCV). SHBG is associated with aging-related diseases, including osteoporosis and frailty in the general population. However, the relationship between SHBG concentration and bone mineral density (BMD) and physical function among PWH and HCV is unclear.

OBJECTIVE

This study aimed to evaluate the association between chronic infection with HIV and HCV and SHBG, and to assess the relationship of circulating SHBG concentrations with low BMD, physical function impairment, and frailty.

METHODS

A cross-sectional study was conducted of 278 HCV-exposed (HCV antibody positive) adults enrolled with and without HIV and HCV from the AIDS Linked to the IntraVenous Experience cohort study into 4 groups: HCV-/HIV-, HCV-/HIV+, HCV+/HIV-, and HCV+/HIV+. We evaluated the association between SHBG concentrations and grip strength, gait speed, Short Physical Performance Battery score, frailty (Fried Frailty Phenotype), and BMD (lumbar spine, total hip, and femoral neck T-score) by using adjusted multivariable regression stratified by sex.

RESULTS

SHBG concentrations were higher in women, in those with HIV RNA greater than 400 copies/mL (P = .02) and HCV RNA greater than 15 IU/mL (P < .001). In adjusted models, higher SHBG concentrations among women were statistically significantly associated with lower grip strength (-0.43 [95% CI, -0.77 to -0.081] kg/10 nmol/L, P < .05), higher odds of frailty (odds ratio, 1.49 [95% CI, 1.07 to 2.08], P < .05), and lower T-scores at the lumbar spine (-0.070 [95% CI, -0.15 to -0.001] SD/10 nmol/L T-score BMD, P < .05). Similar associations were not observed among men.

CONCLUSION

Higher SHBG concentrations are associated with the presence of HIV and HCV viremia. Among women, but not men, higher SHBG concentrations were associated with lower grip strength, higher odds of frailty, and lower lumbar spine BMD. The underlying mechanisms of these associations require further investigation.

The role of the androgen receptor in the pathogenesis of obesity and its utility as a target for obesity treatments

Obesity is associated with hypothalamic-pituitary-testicular axis dysregulation in males. Here, we summarize recent evidence derived from clinical trials and studies in preclinical animal models regarding the role of androgen receptor (AR) signaling in the pathophysiology of males with obesity. We also discuss therapeutic strategies targeting the AR for the treatment of obesity and their limitations and provide insight into the future research necessary to advance this field.

Assessing normalization methods in mass spectrometry-based proteome profiling of clinical samples

BACKGROUND

Large-scale proteomic studies have to deal with unwanted variability, especially when samples originate from different centers and multiple analytical batches are needed. Such variability is typically added throughout all the steps of a clinical research study, from human biological sample collection and storage, sample preparation, spectral data acquisition, to peptide and protein quantification. In order to remove such diverse and unwanted variability, normalization of the protein data is performed. There have been already several published reviews comparing normalization methods in the -omics field, but reports focusing on proteomic data generated with mass spectrometry (MS) are much fewer. Additionally, most of these reports have only dealt with small datasets.

RESULTS

As a case study, here we focused on the normalization of a large MS-based proteomic dataset obtained from an overweight and obese pan-European cohort, where different normalization methods were evaluated, namely: center standardize, quantile protein, quantile sample, global standardization, ComBat, median centering, mean centering, single standard and removal of unwanted variation (RUV); some of these are generic normalization methods while others have been specifically created to deal with genomic or metabolomic data. We checked how relationships between proteins and clinical variables (e.g., gender, levels of triglycerides or cholesterol) were improved after normalizing the data with the different methods.

CONCLUSIONS

Some normalization methods were better adapted for this particular large-scale shotgun proteomic dataset of human plasma samples labeled with isobaric tags and analyzed with liquid chromatography-tandem MS. In particular, quantile sample normalization, RUV, mean and median centering showed very good performance, while quantile protein normalization provided worse results than those obtained with unnormalized data.

Androgens and estrogens predict sexual function after autologous hematopoietic stem cell transplant in men

BACKGROUND

Autologous hematopoietic stem cell transplantation (AHSCT) is associated with sexual dysfunction and hypogonadism. Androgens are associated with sexual function in healthy men, but the role of estrogens is less well-known, and the association of these sex steroids with sexual function during AHSCT has not been characterized.

OBJECTIVES

The purpose of this study was to determine the predictive value of sex hormones before and acutely after AHSCT on sexual function recovery.

MATERIALS AND METHODS

We examined sex hormones and self-reported sexual function before (PRE) and 1-month post-AHSCT (MONTH1; n = 19), and sexual function again 1-year post-AHSCT in men (YEAR1; n = 15).

RESULTS

Sexual function decreased from PRE to MONTH1 (p ≤ 0.05) with no differences between PRE and YEAR1. Erectile dysfunction was prevalent at PRE (68.4%) and increased at MONTH1 (100%; p ≤ 0.05) but was not different between PRE and YEAR1 (60.0%). From PRE to MONTH1, total testosterone (TT), dihydrotestosterone (DHT), follicle-stimulating hormone, and sex-hormone-binding globulin (SHBG) increased (p ≤ 0.02) while estradiol (p ≤ 0.026) and estrone decreased (p ≤ 0.001). MONTH1 TT and DHT were associated with sexual function at MONTH1, while PRE SHBG, MONTH1 estradiol, and change in estrone predicted sexual function at YEAR1.

DISCUSSION

Sexual dysfunction is very prevalent prior to AHSCT and is transiently and severely worsened acutely after. AHSCT induces acute decreases in total and free estrogens, with SHBG increases leading to increases in total androgens, without changes in free androgens.

CONCLUSION

Androgens and estrogens are both adversely affected by AHSCT but may predict sexual dysfunction in this population. This supports the premise that estrogen impacts sexual function independent from androgens and that steroid hormones are associated with acute changes in sexual function in this setting. Larger, controlled trials with long-term sex hormone assessment will need to confirm the association between early changes in estrogens and long-term sexual function recovery.

Menopause, androgens, and cardiovascular ageing: a narrative review

Cardiovascular disease is the leading cause of death worldwide; however, women tend to be less affected than men during their reproductive years. The female cardiovascular risk increases significantly around the time of the menopausal transition. The loss of the protective action of ovarian oestrogens and the circulating androgens has been implicated in possibly inducing subclinical and overt changes in the cardiovascular system after the menopausal transition. In vitro studies performed in human or animal cell lines demonstrate an adverse effect of testosterone on endothelial cell function and nitric oxide bioavailability. Cohort studies evaluating associations between testosterone and/or dehydroepiandrosterone and subclinical vascular disease and clinical cardiovascular events show an increased risk for women with more pronounced androgenicity. However, a mediating effect of insulin resistance is possible. Data on cardiovascular implications following low-dose testosterone treatment in middle-aged women or high-dose testosterone supplementation for gender affirmatory purposes remain primarily inconsistent. It is prudent to consider the possible adverse association between testosterone and endothelial function during the decision-making process of the most appropriate treatment for a postmenopausal woman.

Current Perspectives on Nonalcoholic Fatty Liver Disease in Women with Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is one of the most common reproductive, endocrine, and metabolic disorders in premenopausal women. Clinically, PCOS is mainly caused by androgen excess and ovarian dysfunction, manifested by anovulatory menstrual cycles, infertility, and hirsutism. In addition, PCOS increases the risk of insulin resistance, obesity, cardiovascular disease, anxiety and depression, dyslipidemia, and endometrial cancer. Nonalcoholic fatty liver disease (NAFLD) is defined as ≥5% fat accumulation in the liver in the absence of remaining secondary causes and has become one of the most common chronic liver diseases worldwide. The prevalence of NAFLD is significantly higher and more severe in women with PCOS, and its pathogenesis can be associated with various risk factors such as hyperandrogenemia, insulin resistance, obesity, chronic low-grade inflammation, and genetic factors. Although there is no definitive solution for the management of NAFLD in PCOS, some progress has been made. Lifestyle modification should be the basis of management, and drugs to improve metabolism, such as insulin sensitizers and glucagon-like peptide-1 agonists, may show better efficacy. Bariatric surgery may also be a treatment of NAFLD in obese women with PCOS. This paper reviews three aspects of prevalence, risk factors, and management, in order to better understand the current state of research on NAFLD in PCOS, to explore the pathogenesis of NAFLD in PCOS, and to encourage further research on the application of drugs in this field.

Skeletal muscle wasting: the estrogen side of sexual dimorphism

The importance of defining sex differences across various biological and physiological mechanisms is more pervasive now than it has been over the past 15-20 years. As the muscle biology field pushes to identify small molecules and interventions to prevent, attenuate, or even reverse muscle wasting, we must consider the effect of sex as a biological variable. It should not be assumed that a therapeutic will affect males and females with equal efficacy or equivalent target affinities under conditions where muscle wasting is observed. With that said, it is not surprising to find that we have an unclear or even a poor understanding of the effects of sex or sex hormones on muscle wasting conditions. Although recent investigations are beginning to establish experimental approaches that will allow investigators to assess the impact of sex-specific hormones on muscle wasting, the field still needs rigorous scientific tools that will allow the community to address critical hypotheses centered around sex hormones. The focus of this review is on female sex hormones, specifically estrogens, and the roles that these hormones and their receptors play in skeletal muscle wasting conditions. With the overall review goal of assembling the current knowledge in the area of sexual dimorphism driven by estrogens with an effort to provide insights to interested physiologists on necessary considerations when trying to assess models for potential sex differences in cellular and molecular mechanisms of muscle wasting.

Hypothesis: Metformin is a potential reproductive toxicant

Metformin is the first-line oral treatment for type 2 diabetes mellitus and is prescribed to more than 150 million people worldwide. Metformin's effect as a glucose-lowering drug is well documented but the precise mechanism of action is unknown. A recent finding of an association between paternal metformin treatment and increased numbers of genital birth defects in sons and a tendency towards a skewed secondary sex ratio with less male offspring prompted us to focus on other evidence of reproductive side effects of this drug. Metformin in humans is documented to reduce the circulating level of testosterone in both men and women. In experimental animal models, metformin exposure in utero induced sex-specific reproductive changes in adult rat male offspring with reduced fertility manifested as a 30% decrease in litter size and metformin exposure to fish, induced intersex documented in testicular tissue. Metformin is excreted unchanged into urine and feces and is present in wastewater and even in the effluent of wastewater treatment plants from where it spreads to rivers, lakes, and drinking water. It is documented to be present in numerous freshwater samples throughout the world - and even in drinking water. We here present the hypothesis that metformin needs to be considered a potential reproductive toxicant for humans, and probably also for wildlife. There is an urgent need for studies exploring the association between metformin exposure and reproductive outcomes in humans, experimental animals, and aquatic wildlife.