Testosterone histories from tusks reveal woolly mammoth musth episodes.

Hormones in biological media reveal endocrine activity related to development, reproduction, disease and stress on different timescales1. Serum provides immediate circulating concentrations2, whereas various tissues record steroid hormones accumulated over time3,4. Hormones have been studied in keratin, bones and teeth in modern5-8 and ancient contexts9-12; however, the biological significance of such records is subject to ongoing debate10,13-16, and the utility of tooth-associated hormones has not previously been demonstrated. Here we use liquid chromatography with tandem mass spectrometry paired with fine-scale serial sampling to measure steroid hormone concentrations in modern and fossil tusk dentin. An adult male African elephant (Loxodonta africana) tusk shows periodic increases in testosterone that reveal episodes of musth17-19, an annually recurring period of behavioural and physiological changes that enhance mating success20-23. Parallel assessments of a male woolly mammoth (Mammuthus primigenius) tusk show that mammoths also experienced musth. These results set the stage for wide-ranging studies using steroids preserved in dentin to investigate development, reproduction and stress in modern and extinct mammals. Because dentin grows by apposition, resists degradation, and often contains growth lines, teeth have advantages over other tissues that are used as records of endocrine data. Given the low mass of dentin powder required for analytical precision, we anticipate dentin-hormone studies to extend to smaller animals. Thus, in addition to broad applications in zoology and palaeontology, tooth hormone records could support medical, forensic, veterinary and archaeological studies.

Formin-mediated nuclear actin at androgen receptors promotes transcription.

Steroid hormone receptors are ligand-binding transcription factors essential for mammalian physiology. The androgen receptor (AR) binds androgens mediating gene expression for sexual, somatic and behavioural functions, and is involved in various conditions including androgen insensitivity syndrome and prostate cancer1. Here we identified functional mutations in the formin and actin nucleator DAAM2 in patients with androgen insensitivity syndrome. DAAM2 was enriched in the nucleus, where its localization correlated with that of the AR to form actin-dependent transcriptional droplets in response to dihydrotestosterone. DAAM2 AR droplets ranged from 0.02 to 0.06 µm3 in size and associated with active RNA polymerase II. DAAM2 polymerized actin directly at the AR to promote droplet coalescence in a highly dynamic manner, and nuclear actin polymerization is required for prostate-specific antigen expression in cancer cells. Our data uncover signal-regulated nuclear actin assembly at a steroid hormone receptor necessary for transcription.

The metastatic spread of breast cancer accelerates during sleep.

The metastatic spread of cancer is achieved by the haematogenous dissemination of circulating tumour cells (CTCs). Generally, however, the temporal dynamics that dictate the generation of metastasis-competent CTCs are largely uncharacterized, and it is often assumed that CTCs are constantly shed from growing tumours or are shed as a consequence of mechanical insults1. Here we observe a striking and unexpected pattern of CTC generation dynamics in both patients with breast cancer and mouse models, highlighting that most spontaneous CTC intravasation events occur during sleep. Further, we demonstrate that rest-phase CTCs are highly prone to metastasize, whereas CTCs generated during the active phase are devoid of metastatic ability. Mechanistically, single-cell RNA sequencing analysis of CTCs reveals a marked upregulation of mitotic genes exclusively during the rest phase in both patients and mouse models, enabling metastasis proficiency. Systemically, we find that key circadian rhythm hormones such as melatonin, testosterone and glucocorticoids dictate CTC generation dynamics, and as a consequence, that insulin directly promotes tumour cell proliferation in vivo, yet in a time-dependent manner. Thus, the spontaneous generation of CTCs with a high proclivity to metastasize does not occur continuously, but it is concentrated within the rest phase of the affected individual, providing a new rationale for time-controlled interrogation and treatment of metastasis-prone cancers.

Testosterone Treatment and Fractures in Men with Hypogonadism.

BACKGROUND: Testosterone treatment in men with hypogonadism improves bone density and quality, but trials with a sufficiently large sample and a sufficiently long duration to determine the effect of testosterone on the incidence of fractures are needed. METHODS: In a subtrial of a double-blind, randomized, placebo-controlled trial that assessed the cardiovascular safety of testosterone treatment in middle-aged and older men with hypogonadism, we examined the risk of clinical fracture in a time-to-event analysis. Eligible men were 45 to 80 years of age with preexisting, or high risk of, cardiovascular disease; one or more symptoms of hypogonadism; and two morning testosterone concentrations of less than 300 ng per deciliter (10.4 nmol per liter), in fasting plasma samples obtained at least 48 hours apart. Participants were randomly assigned to apply a testosterone or placebo gel daily. At every visit, participants were asked if they had had a fracture since the previous visit. If they had, medical records were obtained and adjudicated. RESULTS: The full-analysis population included 5204 participants (2601 in the testosterone group and 2603 in the placebo group). After a median follow-up of 3.19 years, a clinical fracture had occurred in 91 participants (3.50%) in the testosterone group and 64 participants (2.46%) in the placebo group (hazard ratio, 1.43; 95% confidence interval, 1.04 to 1.97). The fracture incidence also appeared to be higher in the testosterone group for all other fracture end points. CONCLUSIONS: Among middle-aged and older men with hypogonadism, testosterone treatment did not result in a lower incidence of clinical fracture than placebo. The fracture incidence was numerically higher among men who received testosterone than among those who received placebo. (Funded by AbbVie and others; TRAVERSE ClinicalTrials.gov number, NCT03518034.).

Modular genetic control of sexually dimorphic behaviors.

Sex hormones such as estrogen and testosterone are essential for sexually dimorphic behaviors in vertebrates. However, the hormone-activated molecular mechanisms that control the development and function of the underlying neural circuits remain poorly defined. We have identified numerous sexually dimorphic gene expression patterns in the adult mouse hypothalamus and amygdala. We find that adult sex hormones regulate these expression patterns in a sex-specific, regionally restricted manner, suggesting that these genes regulate sex typical behaviors. Indeed, we find that mice with targeted disruptions of each of four of these genes (Brs3, Cckar, Irs4, Sytl4) exhibit extremely specific deficits in sex specific behaviors, with single genes controlling the pattern or extent of male sexual behavior, male aggression, maternal behavior, or female sexual behavior. Taken together, our findings demonstrate that various components of sexually dimorphic behaviors are governed by separable genetic programs.

Multivariate genetic architecture reveals testosterone-driven sexual antagonism in contemporary humans.

Sex difference (SD) is ubiquitous in humans despite shared genetic architecture (SGA) between the sexes. A univariate approach, i.e., studying SD in single traits by estimating genetic correlation, does not provide a complete biological overview, because traits are not independent and are genetically correlated. The multivariate genetic architecture between the sexes can be summarized by estimating the additive genetic (co)variance across shared traits, which, apart from the cross-trait and cross-sex covariances, also includes the cross-sex-cross-trait covariances, e.g., between height in males and weight in females. Using such a multivariate approach, we investigated SD in the genetic architecture of 12 anthropometric, fat depositional, and sex-hormonal phenotypes. We uncovered sexual antagonism (SA) in the cross-sex-cross-trait covariances in humans, most prominently between testosterone and the anthropometric traits - a trend similar to phenotypic correlations. 27% of such cross-sex-cross-trait covariances were of opposite sign, contributing to asymmetry in the SGA. Intriguingly, using multivariate evolutionary simulations, we observed that the SGA acts as a genetic constraint to the evolution of SD in humans only when selection is sexually antagonistic and not concordant. Remarkably, we found that the lifetime reproductive success in both the sexes shows a positive genetic correlation with anthropometric traits, but not with testosterone. Moreover, we demonstrated that genetic variance is depleted along multivariate trait combinations in both the sexes but in different directions, suggesting absolute genetic constraint to evolution. Our results indicate that testosterone drives SA in contemporary humans and emphasize the necessity and significance of using a multivariate framework in studying SD.

Better together against genetic heterogeneity: A sex-combined joint main and interaction analysis of 290 quantitative traits in the UK Biobank.

Genetic effects can be sex-specific, particularly for traits such as testosterone, a sex hormone. While sex-stratified analysis provides easily interpretable sex-specific effect size estimates, the presence of sex-differences in SNP effect implies a SNP×sex interaction. This suggests the usage of the often overlooked joint test, testing for an SNP's main and SNP×sex interaction effects simultaneously. Notably, even without individual-level data, the joint test statistic can be derived from sex-stratified summary statistics through an omnibus meta-analysis. Utilizing the available sex-stratified summary statistics of the UK Biobank, we performed such omnibus meta-analyses for 290 quantitative traits. Results revealed that this approach is robust to genetic effect heterogeneity and can outperform the traditional sex-stratified or sex-combined main effect-only tests. Therefore, we advocate using the omnibus meta-analysis that captures both the main and interaction effects. Subsequent sex-stratified analysis should be conducted for sex-specific effect size estimation and interpretation.

Hormonal basis of sex differences in anesthetic sensitivity.

General anesthesia-a pharmacologically induced reversible state of unconsciousness-enables millions of life-saving procedures. Anesthetics induce unconsciousness in part by impinging upon sexually dimorphic and hormonally sensitive hypothalamic circuits regulating sleep and wakefulness. Thus, we hypothesized that anesthetic sensitivity should be sex-dependent and modulated by sex hormones. Using distinct behavioral measures, we show that at identical brain anesthetic concentrations, female mice are more resistant to volatile anesthetics than males. Anesthetic sensitivity is bidirectionally modulated by testosterone. Castration increases anesthetic resistance. Conversely, testosterone administration acutely increases anesthetic sensitivity. Conversion of testosterone to estradiol by aromatase is partially responsible for this effect. In contrast, oophorectomy has no effect. To identify the neuronal circuits underlying sex differences, we performed whole brain c-Fos activity mapping under anesthesia in male and female mice. Consistent with a key role of the hypothalamus, we found fewer active neurons in the ventral hypothalamic sleep-promoting regions in females than in males. In humans, we demonstrate that females regain consciousness and recover cognition faster than males after identical anesthetic exposures. Remarkably, while behavioral and neurocognitive measures in mice and humans point to increased anesthetic resistance in females, cortical activity fails to show sex differences under anesthesia in either species. Cumulatively, we demonstrate that sex differences in anesthetic sensitivity are evolutionarily conserved and not reflected in conventional electroencephalographic-based measures of anesthetic depth. This covert resistance to anesthesia may explain the higher incidence of unintended awareness under general anesthesia in females.

Gene-vegetarianism interactions in calcium, estimated glomerular filtration rate, and testosterone identified in genome-wide analysis across 30 biomarkers.

We examined the associations of vegetarianism with metabolic biomarkers using traditional and genetic epidemiology. First, we addressed inconsistencies in self-reported vegetarianism among UK Biobank participants by utilizing data from two dietary surveys to find a cohort of strict European vegetarians (N = 2,312). Vegetarians were matched 1:4 with nonvegetarians for non-genetic association analyses, revealing significant effects of vegetarianism in 15 of 30 biomarkers. Cholesterol measures plus vitamin D were significantly lower in vegetarians, while triglycerides were higher. A genome-wide association study revealed no genome-wide significant (GWS; 5×10-8) associations with vegetarian behavior. We performed genome-wide gene-vegetarianism interaction analyses for the biomarkers, and detected a GWS interaction impacting calcium at rs72952628 (P = 4.47×10-8). rs72952628 is in MMAA, a B12 metabolic pathway gene; B12 has major deficiency potential in vegetarians. Gene-based interaction tests revealed two significant genes, RNF168 in testosterone (P = 1.45×10-6) and DOCK4 in estimated glomerular filtration rate (eGFR) (P = 6.76×10-7), which have previously been associated with testicular and renal traits, respectively. These nutrigenetic findings indicate genotype can modify the associations between vegetarianism and health outcomes.

Cardiovascular Safety of Testosterone-Replacement Therapy.

BACKGROUND: The cardiovascular safety of testosterone-replacement therapy in middle-aged and older men with hypogonadism has not been determined. METHODS: In a multicenter, randomized, double-blind, placebo-controlled, noninferiority trial, we enrolled 5246 men 45 to 80 years of age who had preexisting or a high risk of cardiovascular disease and who reported symptoms of hypogonadism and had two fasting testosterone levels of less than 300 ng per deciliter. Patients were randomly assigned to receive daily transdermal 1.62% testosterone gel (dose adjusted to maintain testosterone levels between 350 and 750 ng per deciliter) or placebo gel. The primary cardiovascular safety end point was the first occurrence of any component of a composite of death from cardiovascular causes, nonfatal myocardial infarction, or nonfatal stroke, assessed in a time-to-event analysis. A secondary cardiovascular end point was the first occurrence of any component of the composite of death from cardiovascular causes, nonfatal myocardial infarction, nonfatal stroke, or coronary revascularization, assessed in a time-to-event analysis. Noninferiority required an upper limit of less than 1.5 for the 95% confidence interval of the hazard ratio among patients receiving at least one dose of testosterone or placebo. RESULTS: The mean (±SD) duration of treatment was 21.7±14.1 months, and the mean follow-up was 33.0±12.1 months. A primary cardiovascular end-point event occurred in 182 patients (7.0%) in the testosterone group and in 190 patients (7.3%) in the placebo group (hazard ratio, 0.96; 95% confidence interval, 0.78 to 1.17; P<0.001 for noninferiority). Similar findings were observed in sensitivity analyses in which data on events were censored at various times after discontinuation of testosterone or placebo. The incidence of secondary end-point events or of each of the events of the composite primary cardiovascular end point appeared to be similar in the two groups. A higher incidence of atrial fibrillation, of acute kidney injury, and of pulmonary embolism was observed in the testosterone group. CONCLUSIONS: In men with hypogonadism and preexisting or a high risk of cardiovascular disease, testosterone-replacement therapy was noninferior to placebo with respect to the incidence of major adverse cardiac events. (Funded by AbbVie and others; TRAVERSE ClinicalTrials.gov number, NCT03518034.).

Psychosocial Functioning in Transgender Youth after 2 Years of Hormones.

BACKGROUND: Limited prospective outcome data exist regarding transgender and nonbinary youth receiving gender-affirming hormones (GAH; testosterone or estradiol). METHODS: We characterized the longitudinal course of psychosocial functioning during the 2 years after GAH initiation in a prospective cohort of transgender and nonbinary youth in the United States. Participants were enrolled in a four-site prospective, observational study of physical and psychosocial outcomes. Participants completed the Transgender Congruence Scale, the Beck Depression Inventory-II, the Revised Children's Manifest Anxiety Scale (Second Edition), and the Positive Affect and Life Satisfaction measures from the NIH (National Institutes of Health) Toolbox Emotion Battery at baseline and at 6, 12, 18, and 24 months after GAH initiation. We used latent growth curve modeling to examine individual trajectories of appearance congruence, depression, anxiety, positive affect, and life satisfaction over a period of 2 years. We also examined how initial levels of and rates of change in appearance congruence correlated with those of each psychosocial outcome. RESULTS: A total of 315 transgender and nonbinary participants 12 to 20 years of age (mean [±SD], 16±1.9) were enrolled in the study. A total of 190 participants (60.3%) were transmasculine (i.e., persons designated female at birth who identify along the masculine spectrum), 185 (58.7%) were non-Latinx or non-Latine White, and 25 (7.9%) had received previous pubertal suppression treatment. During the study period, appearance congruence, positive affect, and life satisfaction increased, and depression and anxiety symptoms decreased. Increases in appearance congruence were associated with concurrent increases in positive affect and life satisfaction and decreases in depression and anxiety symptoms. The most common adverse event was suicidal ideation (in 11 participants [3.5%]); death by suicide occurred in 2 participants. CONCLUSIONS: In this 2-year study involving transgender and nonbinary youth, GAH improved appearance congruence and psychosocial functioning. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development.).

A chemical signal in human female tears lowers aggression in males.

Rodent tears contain social chemosignals with diverse effects, including blocking male aggression. Human tears also contain a chemosignal that lowers male testosterone, but its behavioral significance was unclear. Because reduced testosterone is associated with reduced aggression, we tested the hypothesis that human tears act like rodent tears to block male aggression. Using a standard behavioral paradigm, we found that sniffing emotional tears with no odor percept reduced human male aggression by 43.7%. To probe the peripheral brain substrates of this effect, we applied tears to 62 human olfactory receptors in vitro. We identified 4 receptors that responded in a dose-dependent manner to this stimulus. Finally, to probe the central brain substrates of this effect, we repeated the experiment concurrent with functional brain imaging. We found that sniffing tears increased functional connectivity between the neural substrates of olfaction and aggression, reducing overall levels of neural activity in the latter. Taken together, our results imply that like in rodents, a human tear-bound chemosignal lowers male aggression, a mechanism that likely relies on the structural and functional overlap in the brain substrates of olfaction and aggression. We suggest that tears are a mammalian-wide mechanism that provides a chemical blanket protecting against aggression.

Diurnal Fluctuations in Steroid Hormones Tied to Variation in Intrinsic Functional Connectivity in a Densely Sampled Male.

Most of mammalian physiology is under the control of biological rhythms, including the endocrine system with time-varying hormone secretion. Precision neuroimaging studies provide unique insights into how the endocrine system dynamically regulates aspects of the human brain. Recently, we established estrogen's ability to drive widespread patterns of connectivity and enhance the global efficiency of large-scale brain networks in a woman sampled every 24 h across 30 consecutive days, capturing a complete menstrual cycle. Steroid hormone production also follows a pronounced sinusoidal pattern, with a peak in testosterone between 6 and 7 A.M. and nadir between 7 and 8 P.M. To capture the brain's response to diurnal changes in hormone production, we carried out a companion precision imaging study of a healthy adult man who completed MRI and venipuncture every 12-24 h across 30 consecutive days. Results confirmed robust diurnal fluctuations in testosterone, 17ß-estradiol-the primary form of estrogen-and cortisol. Standardized regression analyses revealed widespread associations between testosterone, estradiol, and cortisol concentrations and whole-brain patterns of coherence. In particular, functional connectivity in the Dorsal Attention Network was coupled with diurnally fluctuating hormones. Further, comparing dense-sampling datasets between a man and a naturally cycling woman revealed that fluctuations in sex hormones are tied to patterns of whole-brain coherence in both sexes and to a heightened degree in the male. Together, these findings enhance our understanding of steroid hormones as rapid neuromodulators and provide evidence that diurnal changes in steroid hormones are associated with patterns of whole-brain functional connectivity.

Testosterone's role in modulating human behaviors relevant to mating and parenting.

Testosterone (T) is linked to human mating and parenting. Here, we comprehensively reviewed evidence on whether, in men and women, (1) basal T levels are related to mating and parenting behaviors, (2) T responds to reproduction-relevant cues, (3) acute changes in T map onto subsequent mating and parenting behaviors, and (4) single-dose exogenous T administration causally affects mating and parenting behaviors. We examined whether the available evidence supports trade-off interpretations of T's adaptive function whereby high T levels correspond to greater mating/reproductive effort and competition and low T levels to greater parenting effort and nurturance. We found mixed support for trade-off hypotheses, suggesting that T's function in modulating human mating and parenting might be more nuanced and highly dependent on context and individual trait differences. Results were largely similar for men and women, although studies with women were scarcer than those with men for most behaviors we reviewed.

Understanding One Half of the Sex Difference Equation: The Modulatory Effects of Testosterone on Diabetic Cardiomyopathy.

Diabetes is a prevalent disease, primarily characterized by high blood sugar (hyperglycemia). Significantly higher rates of myocardial dysfunction have been noted in individuals with diabetes, even in those without coronary artery disease or high blood pressure (hypertension). Numerous molecular mechanisms have been identified through which diabetes contributes to the pathology of diabetic cardiomyopathy, which presents as cardiac hypertrophy and fibrosis. At the cellular level, oxidative stress and inflammation in cardiomyocytes are triggered by hyperglycemia. Although males are generally more likely to develop cardiovascular disease than females, diabetic males are less likely to develop diabetic cardiomyopathy than are diabetic females. One reason for these differences may be the higher levels of serum testosterone in males compared with females. Although testosterone appears to protect against cardiomyocyte oxidative stress and exacerbate hypertrophy, its role in inflammation and fibrosis is much less clear. Additional preclinical and clinical studies will be required to delineate testosterone's effect on the diabetic heart.

Compensated Hypogonadism Identified in Males with Cluster Headache: A Prospective Case-Controlled Study.

OBJECTIVE: Androgens have been hypothesized to be involved in the pathophysiology of cluster headache due to the male predominance, but whether androgens are altered in patients with cluster headache remains unclear. METHODS: We performed a prospective, case-controlled study in adult males with cluster headache. Sera were measured for hormones including testosterone, luteinizing hormone (LH), and sex hormone-binding globulin in 60 participants with episodic cluster headache (during a bout and in remission), 60 participants with chronic cluster headache, and 60 age- and sex-matched healthy controls. Free testosterone (fT) was calculated according to the Vermeulen equation. Shared genetic risk variants were assessed between cluster headache and testosterone concentrations. RESULTS: The mean fT/LH ratio was reduced by 35% (95% confidence interval [CI]: 21%-47%, p < 0.0001) in patients with chronic cluster headache and by 24% (95% CI: 9%-37%, p = 0.004) in patients with episodic cluster headache compared to controls after adjusting for age, sleep duration, and use of acute medication. Androgen concentrations did not differ between bouts and remissions. Furthermore, a shared genetic risk allele, rs112572874 (located in the intron of the microtubule associated protein tau (MAPT) gene on chromosome 17), between fT and cluster headache was identified. INTERPRETATION: Our results demonstrate that the male endocrine system is altered in patients with cluster headache to a state of compensated hypogonadism, and this is not an epiphenomenon associated with sleep or the use of acute medication. Together with the identified shared genetic risk allele, this may suggest a pathophysiological link between cluster headache and fT. ANN NEUROL 2024;95:1149-1161.

Androgenic steroids induce pathologic scarring in a preclinical porcine model via dysfunctional extracellular matrix deposition.

Hypertrophic scarring is a major source of morbidity. Sex hormones are not classically considered modulators of scarring. However, based on increased frequency of hypertrophic scarring in patients on testosterone, we hypothesized that androgenic steroids induce abnormal scarring and developed a preclinical porcine model to explore these effects. Mini-swine underwent castration, received no testosterone (noT) or biweekly testosterone therapy (+T), and underwent excisional wounding. To create a delayed wound healing model, a subset of wounds were re-excised at 2 weeks. Scars from postoperative day 42 (POD42) and delayed wounds (POD28) were harvested 6 weeks after initial wounding for analysis via histology, bulk RNA-seq, and mechanical testing. Histologic analysis of scars from +T animals showed increased mean fibrosis area (16 mm2noT, 28 mm2+T; p = .007) and thickness (0.246 mm2noT, 0.406 mm2+T; p < .001) compared to noT. XX+T and XY+T scars had greater tensile burst strength (p = .024 and p = .013, respectively) compared to noT swine. Color deconvolution analysis revealed greater deposition of type I and type III collagen as well as increased collagen type I:III ratio in +T scars. Dermatopathologist histology scoring showed that +T exposure was associated with worse overall scarring (p < .05). Gene ontology analysis found that testosterone exposure was associated with upregulation of cellular metabolism and immune response gene sets, while testosterone upregulated pathways related to keratinization and laminin formation on pathway analysis. In conclusion, we developed a preclinical porcine model to study the effects of the sex hormone testosterone on scarring. Testosterone induces increased scar tissue deposition and appears to increase physical strength of scars via supraphysiologic deposition of collagen and other ECM factors. The increased burst strength seen in both XX and XY animals suggests that hormone administration has a strong influence on scar mechanical properties independent of chromosomal sex. Anti-androgen topical therapies may be a promising future area of research.

Androgen synthesis cell-specific CREBZF deficiency alters adrenal cortex steroid secretion and develops behavioral abnormalities in adult male mice.

The global challenge of male infertility is escalating, notably due to the decreased testosterone (T) synthesis in testicular Leydig cells under stress, underscoring the critical need for a more profound understanding of its regulatory mechanisms. CREBZF, a novel basic region-leucine zipper transcription factor, regulates testosterone synthesis in mouse Leydig cells in vitro; however, further validation through in vivo experiments is essential. Our study utilized Cyp17a1-Cre to knock out CREBZF in androgen-synthesis cells and explored the physiological roles of CREBZF in fertility, steroid hormone synthesis, and behaviors in adult male mice. Conditional knockout (cKO) CREBZF did not affect fertility and serum testosterone level in male mice. Primary Leydig cells isolated from CREBZF-cKO mice showed impaired testosterone secretion and decreased mRNA levels of Star, Cyp17a1, and Hsd3b1. Loss of CREBZF resulted in thickening of the adrenal cortex, especially X-zone, with elevated serum corticosterone and dehydroepiandrosterone levels and decreased serum dehydroepiandrosterone sulfate levels. Immunohistochemical staining revealed increased expression of StAR, Cyp11a1, and 17ß-Hsd3 in the adrenal cortex of CREBZF-cKO mice, while the expression of AR was significantly reduced. Along with the histological changes and abnormal steroid levels in the adrenal gland, CREBZF-cKO mice showed higher anxiety-like behavior and impaired memory in the elevated plus maze and Barnes maze, respectively. In summary, CREBZF is dispensable for fertility, and CREBZF deficiency in Leydig cells promotes adrenal function in adult male mice. These results shed light on the requirement of CREBZF for fertility, adrenal steroid synthesis, and stress response in adult male mice, and contribute to understanding the crosstalk between testes and adrenal glands.

Interplay between hippocampal TACR3 and systemic testosterone in regulating anxiety-associated synaptic plasticity.

Tachykinin receptor 3 (TACR3) is a member of the tachykinin receptor family and falls within the rhodopsin subfamily. As a G protein-coupled receptor, it responds to neurokinin B (NKB), its high-affinity ligand. Dysfunctional TACR3 has been associated with pubertal failure and anxiety, yet the mechanisms underlying this remain unclear. Hence, we have investigated the relationship between TACR3 expression, anxiety, sex hormones, and synaptic plasticity in a rat model, which indicated that severe anxiety is linked to dampened TACR3 expression in the ventral hippocampus. TACR3 expression in female rats fluctuates during the estrous cycle, reflecting sensitivity to sex hormones. Indeed, in males, sexual development is associated with a substantial increase in hippocampal TACR3 expression, coinciding with elevated serum testosterone and a significant reduction in anxiety. TACR3 is predominantly expressed in the cell membrane, including the presynaptic compartment, and its modulation significantly influences synaptic activity. Inhibition of TACR3 activity provokes hyperactivation of CaMKII and enhanced AMPA receptor phosphorylation, associated with an increase in spine density. Using a multielectrode array, stronger cross-correlation of firing was evident among neurons following TACR3 inhibition, indicating enhanced connectivity. Deficient TACR3 activity in rats led to lower serum testosterone levels, as well as increased spine density and impaired long-term potentiation (LTP) in the dentate gyrus. Remarkably, aberrant expression of functional TACR3 in spines results in spine shrinkage and pruning, while expression of defective TACR3 increases spine density, size, and the magnitude of cross-correlation. The firing pattern in response to LTP induction was inadequate in neurons expressing defective TACR3, which could be rectified by treatment with testosterone. In conclusion, our study provides valuable insights into the intricate interplay between TACR3, sex hormones, anxiety, and synaptic plasticity. These findings highlight potential targets for therapeutic interventions to alleviate anxiety in individuals with TACR3 dysfunction and the implications of TACR3 in anxiety-related neural changes provide an avenue for future research in the field.

FSH Is Responsible for Androgen Deprivation Therapy-Associated Atherosclerosis in Mice by Exaggerating Endothelial Inflammation and Monocyte Adhesion.

BACKGROUND: Androgen deprivation therapy (ADT) is the mainstay treatment for advanced prostate cancer. But ADTs with orchiectomy and gonadotropin-releasing hormone (GnRH) agonist are associated with increased risk of cardiovascular diseases, which appears less significant with GnRH antagonist. The difference of follicle-stimulating hormone (FSH) in ADT modalities is hypothesized to be responsible for ADT-associated cardiovascular diseases. METHODS: We administered orchiectomy, GnRH agonist, or GnRH antagonist in male ApoE-/- mice fed with Western diet and manipulated FSH levels by testosterone and FSH supplementation or FSH antibody to investigate the role of FSH elevation on atherosclerosis. By combining lipidomics, in vitro study, and intraluminal FSHR (FSH receptor) inhibition, we delineated the effects of FSH on endothelium and monocytes and the underlying mechanisms. RESULTS: Orchiectomy and GnRH agonist, but not GnRH antagonist, induced long- or short-term FSH elevation and significantly accelerated atherogenesis. In orchiectomized and testosterone-supplemented mice, FSH exposure increased atherosclerosis. In GnRH agonist-treated mice, blocking of short FSH surge by anti-FSHß antibody greatly alleviated endothelial inflammation and delayed atherogenesis. In GnRH antagonist-treated mice, FSH supplementation aggravated atherogenesis. Mechanistically, FSH, synergizing with TNF-α (tumor necrosis factor alpha), exacerbated endothelial inflammation by elevating VCAM-1 (vascular cell adhesion protein 1) expression through the cAMP/PKA (protein kinase A)/CREB (cAMP response element-binding protein)/c-Jun and PI3K (phosphatidylinositol 3 kinase)/AKT (protein kinase B)/GSK-3ß (glycogen synthase kinase 3 beta)/GATA-6 (GATA-binding protein 6) pathways. In monocytes, FSH upregulated CD29 (cluster of differentiation 29) expression via the PI3K/AKT/GSK-3ß/SP1 (specificity protein 1) pathway and promoted monocyte-endothelial adhesion both in vitro and in vivo. Importantly, FSHR knockdown by shRNA in endothelium of carotid arteries markedly reduced GnRH agonist-induced endothelial inflammation and atherosclerosis in mice. CONCLUSIONS: FSH is responsible for ADT-associated atherosclerosis by exaggerating endothelial inflammation and promoting monocyte-endothelial adhesion.