Revisiting the physiological role of androgens in women

Comparative insights into the role of sex hormones in glaucoma among women and men

Baseline differences in sex hormone levels between males and females influence tissues including the brain and eye. To investigate the effects of estrogens and androgens on ocular physiology and glaucoma, we review the current literature on the influence of primary sex hormones on ocular function, glaucoma incidence and related parameters like intraocular pressure (IOP) at physiologic levels and related to hormone therapies in men and women. These articles reveal activity of estrogen, testosterone, and progesterone within ocular tissues including the retinal pigment epithelium and ciliary epithelium where they likely influence glaucoma pathophysiology through effects on ocular blood flow and aqueous outflow. A growing body of evidence demonstrates a protective role of estrogen in glaucoma. With fluctuations across a woman's lifetime through menstrual phases, pregnancy, and menopause, the general association seen is a lower risk of glaucoma and lower IOP with higher estrogen. Exogenous hormones in the form of oral contraceptive pills and hormone replacement therapy also appear to affect glaucoma risk, although published findings are inconsistent. Few studies have reported a positive association between IOP and serum testosterone, and men treated with androgen deprivation therapy have shown a reduced risk of glaucoma while masculinizing hormone therapies at supra-physiologic testosterone levels have significantly increased IOP. Sex hormone perturbations affect components of glaucoma pathogenesis including IOP and ocular blood flow and overlap with known risk factors like age and sex. Standardized studies are needed to further elucidate the roles of estrogen and testosterone in glaucoma risk and progression.

Adrenomedullin gene delivery rescues estrogen production in Leydig cells via the inhibition of TGF-β1/Smads signaling pathway

Our previous findings demonstrated that adrenomedullin (ADM) protects against the reduction in testosterone production and apoptosis of Leydig cells both in vitro and in vivo. In this study, we investigated whether ADM could preserve estrogen production in Leydig cells by suppressing the transforming growth factor-β1 (TGF-β1) / Smads signaling pathway. Leydig cells were treated with lipopolysaccharide (LPS) and recombinant adenovirus ADM (Ad-ADM), an adeno-associated viral vector expressing ADM. Cell viability and cytochrome P450 aromatase (P450arom) activity were assessed. Estrogen, testosterone, and TGF-β1 concentrations in the culture medium were measured. Additionally, the gene expression and protein levels of CYP19, TGF-β1, and Smads were evaluated. The results indicated that Ad-ADM mitigated the reductions in Leydig cell viability and testosterone production, counteracted the decreases in P450arom activity, and restored CYP19 gene expression and protein levels in LPS-treated cells. Moreover, Ad-ADM reduced the elevated gene expression and protein levels of Smads and TGF-β1 induced by LPS. Based on these findings, we propose that ADM safeguards estrogen production in Leydig cells by inhibiting the TGF-β1/Smads signaling pathway.

Sex, Age, and Previous Herpes Zoster Infection Role on Adverse Events Following Immunization with Adjuvanted Recombinant Vaccine

Adverse events following immunizations (AEFIs) with recombinant zoster vaccine (RZV) are underexplored in fragile populations. This study aims to assess incidence, duration, and characteristics of AEFIs, focusing on the impact of sex, age, and prior Herpes Zoster (HZ) infection in a frail population, including solid organ transplant recipients. We conducted an observational study on patients receiving RZV, and AEFIs were classified as local or systemic and analyzed for incidence, duration, and patterns across groups. We showed that females had a higher incidence of AEFIs (p = 0.02), both local and systemic symptoms, such as swelling +/- redness at the site of injection and fatigue, after the first and second doses. Younger adults experienced more systemic reactions, while older adults reported more local events (e.g., redness and swelling, p = 0.01). Moreover, patients with previous HZ infection exhibited a higher incidence of AEFIs after the second dose (68% vs. 38%, p = 0.001). In conclusion, sex, age, and clinical history significantly influenced AEFI incidence and manifestations. Therefore, it is important to personalize vaccination strategies in frail populations, by tailored administration and monitoring plans, especially in females and individuals with prior HZ infection, to improve vaccine safety and patient outcomes.

Molecular mechanism underlying cardioprotective effect of dehydroepiandrosterone on endoplasmic reticulum stress induced apoptosis in human vascular smooth muscle cells and human umbilical vein endothelial cells

Introduction

This study aimed to investigate the underlying mechanisms involved in the cardioprotective effects of dehydroepiandrosterone (DHEA) on endoplasmic reticulum stress (ERS) -mediated apoptosis in human vascular smooth muscle cells (HVSMCs) and human umbilical vein endothelial cells (HUVECs).

Material and methods

Various concentrations of Dithiothreitol (DTT) were used to induce ERS-mediated apoptosis. DHEA was utilized to inhibit the apoptotic effects of DTT, while estrogen receptor (ER) antagonists ICI 182,780 and G15, the androgen receptor (AR) antagonist flutamide and the aromatase inhibitor letrozole were used to identify the receptors activated during DHEA treatment in HVSMCs and HUVECs. Flow cytometry assessed the apoptotic rate, and Western blotting analysis evaluated the expression levels of ERS-related proteins GRP78 and PERK, and the apoptotic protein marker CHOP. Furthermore, the primary receptor signaling pathways were identified using signaling pathway blockers: LY294002 (PI3K blocker), SP600125 (JNK blocker), and U0126 (ERK1/2 blocker).

Results

In the DTT pretreatment group (0.8 mmol/L, for 8 h), the expressions of GRP78 and CHOP were significantly up regulated, indicating that an optimal ERS model was successfully established. Additionally, 10-4 mmol/L DHEA significantly inhibited the DTT-induced upregulation of GRP78 and CHOP. The results also demonstrated that the apoptotic rate in the DTT group was increased, while DHEA significantly reduced this rate. The addition of ER antagonists ICI 182,780 and G15 to HVSMCs reversed the effects of DHEA; however, the aromatase inhibitor letrozole and the AR antagonist flutamide did not reverse this effect. Notably, the use of the JNK inhibitor SP600125, the PI3K inhibitor LY294002, and the ERK1/2 inhibitor U0126 antagonized the protective effects of DHEA, with SP600125 showing the most significant impact on both HVSMCs and HUVECs.

Conclusion

Our study has identified a novel mechanism underlying the cardioprotective effects of DHEA. Specifically, DHEA may mitigate ERS-induced cell apoptosis by activating estrogen receptors ERα, ERβ, and GPER via the activated JNK pathway.

Association Between Female Androgen Levels, Metabolic Syndrome, and Cardiovascular Disease: An NHANES Analysis (2013-2016)

Background

The impact of androgens on metabolic diseases, cardiovascular diseases (CVD), and long-term mortality in the general female population remains poorly understood. This study, utilizing data from the National Health and Nutrition Examination Survey (NHANES) database managed by the Centers for Disease Control and Prevention, seeks to elucidate the relationship between androgen levels and metabolic syndrome (MS), CVD, and mortality in adult women.

Methods

After excluding ineligible individuals, descriptive analyses were conducted on demographic characteristics, metabolic-related indicators, and disease prevalence, based on the presence of high androgenemia and androgen quartile grouping. Logistic regression models were developed to assess the associations of androgen markers, including total testosterone (TT), Free Androgen Index (FAI), with MS, CVD, and cox regression models were used to explore the relationships with mortality.

Results

Our results show that, even without adjustment for age, age at menarche, marital status, and smoking status, both in patients with hyperandrogenemia and across the general population stratified by quartiles of FAI, higher androgen levels are associated with increased waist circumference, weight, Body Mass Index, fasting insulin, and the monocyte/high-density lipoprotein cholesterol ratio. In adjusted correlational analysis, MS remained positively correlated with FAI, even after controlling for age, tobacco use, and alcohol consumption. As FAI quartiles increased, the correlation strengthened, achieving an odds ratio (OR) of 1.45 (95% CI 1.04 to 2.02, P=0.03) in the highest quartile. This indicates that androgen levels are strongly associated with metabolic syndrome, with FAI proving more sensitive than TT.

Conclusion

The greater sensitivity of FAI may be attributed to its ability to reflect bioavailable testosterone more accurately than TT, underscoring its potential utility in clinical assessments of metabolic risk. This study found no significant correlation between androgen levels and CVD or mortality.

Impact of dehydroepiandrosterone sulfate and free androgen index on pregnancy and neonatal outcomes in PCOS patients

BACKGROUND

Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder associated with infertility and pregnancy complications. The pathogenesis of PCOS and its impact on reproductive function may be influenced by the source of androgens, including testosterone, free androgen, dehydroepiandrosterone sulfate (DHEAS). However, the differential effects of these androgen on pregnancy and neonatal outcomes and the cut-off value of East Asian population with PCOS remain unclear.

METHODS

A retrospective cohort study was conducted at the Reproductive Medicine Center of the First Affiliated Hospital of Sun Yat-sen University from January 2015 to November 2022, involving 636 cycles of in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI). Subgroup analyses were performed using cut-off values of 6.4 for free androgen index (FAI), 9.5 µmol/L for DHEAS. Pregnancy and neonatal outcomes were compared between groups. Restricted cubic spline (RCS) was used to identify significant cut-off values affecting pregnancy.

RESULTS

Higher FAI levels (> 6.4) were associated with decrease in clinical pregnancy rate (PR) (50.61% vs. 41.66%, p = 0.024), live birth rate (LBR) (42.42% vs. 32.35%, p = 0.011). When DHEAS levels exceeded 9.5 µmol/L, there was a significant decrease in clinical PR (51.27% vs. 42.73%, P = 0.039), LBR (42.73% vs. 32.73%, P = 0.012). Negative correlations were also observed between DHEAS levels and cumulative pregnancy rate (70.57% vs 56.62% p = 0.002) and cumulative live birth rate (CLBR) (59.35% vs 43.37%, p = 0.0007). Both FAI and DHEAS elevated is associated with the lowest clinical pregnancy rate (37.84%). Conversely, when solely FAI is elevated, the pregnancy rate increases to 52.38%, while an elevation in DHEAS alone is associated with a pregnancy rate of, both of which are lower than when neither FAI nor DHEAS are elevated (60.68%). The live birth rates exhibit a similar trend (30.00% vs 40.00% vs 41.83% vs 44.48%). RCS revealed a significant decrease in CPR and CLBR when DHEA levels exceeded 7.69 umol/L, while the cut-off value of FAI was 6.36 for CPR and CLBR.

CONCLUSION

In conclusion, PCOS patients with biochemical hyperandrogenism show unsatisfactory clinical PR and CLBR when undergoing assisted reproductive technology (ART). This may be attributed to the influence of both adrenal-derived DHEAS and ovarian-derived FAI on the unfavorable pregnancy outcomes.

Androgen receptors and sociosexual behaviors in mammals: The limits of generalization

Circulating testosterone is easily aromatized to estradiol and reduced to dihydrotestosterone in target tissues and elsewhere in the body. Thus, the actions of testosterone can be mediated either by the estrogen receptors, the androgen receptor or by simultaneous action at both receptors. To determine the role of androgens acting at the androgen receptor, we need to eliminate actions at the estrogen receptors. Alternatively, actions at the androgen receptor itself can be eliminated. In the present review, I will analyze the specific role of androgen receptors in male and female sexual behavior as well as in aggression. Some comments about androgen receptors and social recognition are also made. It will be shown that there are important differences between species, even between strains within a species, concerning the actions of the androgen receptor on the behaviors mentioned. This fact makes generalizations from one species to another or from one strain to another very risky. The existence of important species differences is often ignored, leading to many misunderstandings and much confusion.

Diversity of Androgens; Comparison of Their Significance and Characteristics in Vertebrate Species

Androgen(s) is one of the sex steroids that are involved in many physiological phenomena of vertebrate species. Although androgens were originally identified as male sex hormones, it is well known now that they are also essential in females. As in the case of other steroid hormones, androgen is produced from cholesterol through serial enzymatic reactions. Although testis is a major tissue to produce androgens in all species, androgens are also produced in ovary and adrenal (interrenal tissue). Testosterone is the most common and famous androgen. It represents a major androgen both in males and females of almost vertebrate species. In addition, testosterone is a precursor for producing significant androgens such as11-ketotestosterone, 5α-dihydrotestosterone, 11-ketodihydrotestosterones and 15α-hydroxytestosterone in a species- or sex-dependent manner for their homeostasis. In this article, we will review the significance and characteristics of these androgens, following a description of the history of testosterone discovery and its synthetic pathways.

Clinical management of androgen excess and defect in women

INTRODUCTION

Hyperandrogenism and hypoandrogenism are complex disorders involving multiple-organ systems. While androgen excess is a well-characterized condition, androgen deficiency still needs diagnostic criteria, as there are no specific cutoffs.

AREAS COVERED

We highlight the most recent findings on the role of androgens in female pathophysiology, investigating clinically relevant conditions of androgen insufficiency or excess throughout a woman's life, and their possible therapeutic management.

EXPERT OPINION

Combined oral contraceptives (COCs) should be considered as first-line therapy for the management of menstrual irregularity and/or clinical hyperandrogenism in adolescents with a clear diagnosis of polycystic ovary syndrome (PCOS). There are limited evidence-based data regarding specific types or doses of COCs for management of PCOS in women; however, the lowest effective estrogen dose should be considered for treatment. Despite evidence regarding safety, efficacy, and clinical use, testosterone therapy has not been approved for women by most regulatory agencies for treatment of hypoactive sexual desire disorder (HSDD). The long-term safety for treatments with testosterone is still to be evaluated, and this review highlights the need for more research in this area.

How Food Choices Impact on Male Fertility

PURPOSE OF REVIEW

Increasing evidence on the significance of nutrition in reproduction is emerging from both animal and human studies, suggesting an association between nutrition and male fertility. Here, we have highlighted the impact of the various food groups on reproductive hormones and on spermatogenesis, and the effects of classical and latest dietary patterns such as Mediterranean diet, Western diet, intermittent fasting, ketogenic diet, and vegan/vegetarian diet on male fertility.

RECENT FINDINGS

Nutrients are the precursors of molecules involved in various body's reactions; therefore, their balance is essential to ensure the correct regulation of different systems including the endocrine system. Hormones are strongly influenced by the nutritional status of the individual, and their alteration can lead to dysfunctions or diseases like infertility. In addition, nutrients affect sperm production and spermatogenesis, controlling sexual development, and maintaining secondary sexual characteristics and behaviors. The consumption of fruit, vegetables, fish, processed meats, dairy products, sugars, alcohol, and caffeine importantly impact on male fertility. Among dietary patterns, the Mediterranean diet and the Western diet are most strongly associated with the quality of semen. Nutrients, dietary patterns, and hormonal levels have an impact on male infertility. Therefore, understanding how these factors interact with each other is important for strategies to improve male fertility.

Bone health and prevalent fractures in women with polycystic ovary syndrome: a meta-analysis and endocrine-context pathophysiology review

INTRODUCTION

Bone health in those with Polycystic Ovary Syndrome (PCOS) is complex, but the general consensus is that cortical areal bone mineral density (aBMD) sites will be higher in PCOS than in age- and BMI-similar controls. However, spine aBMD sites may be lower, especially in non-obese PCOS. Whether or not incident fracture risk is increased in PCOS is currently controversial; no meta-analysis has yet assessed prevalent fractures.

AREAS COVERED

We assessed the bone effects of PCOS-related ovarian hormone alterations, e.g. androgen excess, tonically normal/higher estradiol, and lower-than-normal progesterone levels. We also highlighted evidence that common PCOS medications (e.g. combined hormonal contraceptives [CHC], metformin, and spironolactone) have important bone effects. In adolescents, meta-analysis of CHC showed significant negative aBMD changes. Inflammation has negative PCOS bone effects and is linked with CHC use.

EXPERT OPINION

Is fracture risk altered by PCOS? Our meta-analysis showed a 25% increased risk of prevalent fracture in PCOS versus controls; this did not reach statistical significance. Future prospective research needs to collect and evaluate ovulation characteristics, progesterone exposure, and adolescent CHC use, in addition to the complex variables that may influence risks for prevalent or incident fragility fractures and/or for cortical and cancellous aBMD values in PCOS.

Regulation of Bone by Mechanical Loading, Sex Hormones, and Nerves: Integration of Such Regulatory Complexity and Implications for Bone Loss during Space Flight and Post-Menopausal Osteoporosis

During evolution, the development of bone was critical for many species to thrive and function in the boundary conditions of Earth. Furthermore, bone also became a storehouse for calcium that could be mobilized for reproductive purposes in mammals and other species. The critical nature of bone for both function and reproductive needs during evolution in the context of the boundary conditions of Earth has led to complex regulatory mechanisms that require integration for optimization of this tissue across the lifespan. Three important regulatory variables include mechanical loading, sex hormones, and innervation/neuroregulation. The importance of mechanical loading has been the target of much research as bone appears to subscribe to the "use it or lose it" paradigm. Furthermore, because of the importance of post-menopausal osteoporosis in the risk for fractures and loss of function, this aspect of bone regulation has also focused research on sex differences in bone regulation. The advent of space flight and exposure to microgravity has also led to renewed interest in this unique environment, which could not have been anticipated by evolution, to expose new insights into bone regulation. Finally, a body of evidence has also emerged indicating that the neuroregulation of bone is also central to maintaining function. However, there is still more that is needed to understand regarding how such variables are integrated across the lifespan to maintain function, particularly in a species that walks upright. This review will attempt to discuss these regulatory elements for bone integrity and propose how further study is needed to delineate the details to better understand how to improve treatments for those at risk for loss of bone integrity, such as in the post-menopausal state or during prolonged space flight.

Gender-Specific Impact of Sex Hormones on the Immune System

Sex hormones are key determinants of gender-related differences and regulate growth and development during puberty. They also exert a broad range modulation of immune cell functions, and a dichotomy exists in the immune response between the sexes. Both clinical and animal models have demonstrated that androgens, estrogens, and progestogens mediate many of the gender-specific differences in immune responses, from the susceptibility to infectious diseases to the prevalence of autoimmune disorders. Androgens and progestogens mainly promote immunosuppressive or immunomodulatory effects, whereas estrogens enhance humoral immunity both in men and in women. This study summarizes the available evidence regarding the physiological effects of sex hormones on human immune cell function and the underlying biological mechanisms, focusing on gender differences triggered by different amounts of androgens between males and females.