The circadian clock is an important internal time regulatory system for a range of physiological and behavioral rhythms within living organisms. Testosterone, as one of the most critical sex hormones, is essential for the development of the reproductive system, maintenance of reproductive function, and the overall health of males. The secretion of testosterone in mammals is characterized by distinct circadian rhythms and is closely associated with the regulation of circadian clock genes. Here we review the central and peripheral regulatory mechanisms underlying the influence of circadian clock genes upon testosterone synthesis. We also examined the specific effects of these genes on the occurrence, development, and treatment of common male diseases, including late-onset hypogonadism, erectile dysfunction, male infertility, and prostate cancer.
Testosterone/metabolism* ; Humans ; Male ; Circadian Clocks/genetics* ; Circadian Rhythm Signaling Peptides and Proteins/metabolism* ; Circadian Rhythm/physiology* ; Hypogonadism/metabolism* ; Erectile Dysfunction/metabolism* ; Infertility, Male/metabolism* ; Prostatic Neoplasms/metabolism* ; Men's Health

Recently, male reproductive health has attracted extensive attention, with the adverse effects of circadian disruption on male fertility gradually gaining recognition. However, the mechanism by which circadian disruption leads to damage to male reproductive system remains unclear. In this review, we first summarized the dual regulatory roles of circadian clock genes on the male reproductive system: (1) circadian regulation of testosterone synthesis via the hypothalamic-pituitary-testicular (HPT) and hypothalamic-pituitary-adrenal (HPA) axes; (2) non-circadian regulation of spermatogenesis. Next, we further listed the possible mechanisms by which circadian disruption impairs male fertility, including interference with the oscillatory function of the reproductive system, i.e., synchronization of the HPT axis, crosstalk between the HPT axis and the HPA axis, as well as direct damage to germ cells by disturbing the non-oscillatory function of the reproductive system. Future research using spatiotemporal omics, epigenomic assays, and neural circuit mapping in studying the male reproductive system may provide new clues to systematically unravel the mechanisms by which circadian disruption affects male reproductive system through circadian clock genes.
Male ; Humans ; Animals ; Circadian Clocks/physiology* ; Hypothalamo-Hypophyseal System/physiology* ; Circadian Rhythm/genetics* ; Spermatogenesis/physiology* ; Pituitary-Adrenal System/physiology* ; Testis/physiology* ; Testosterone/biosynthesis* ; CLOCK Proteins ; Infertility, Male/physiopathology*

As the social pressure is increasing,the incidence of depression is growing.Testosterone is synthesized and secreted through the hypothalamic-pituitary-gonadal axis,which plays a regulatory role in men's mental health.Studies have shown that low testosterone levels,clinical hypogonadism,and androgen deprivation therapy-induced testosterone deficiency are significantly associated with male depression,while there are still many uncertainties about the mechanism of their effects.Given that low testosterone levels may serve as a characteristic biomarker of male depression risk,testosterone replacement therapy may have a good therapeutic effect on male depression.This article focuses on assessing the role of testosterone levels and related clinical therapies in mood regulation in men.
Humans ; Testosterone/physiology* ; Male ; Depression/etiology* ; Hormone Replacement Therapy

BACKGROUND: The association between sex hormone-binding globulin (SHBG) and renal function has rarely been reported in men. We aimed to investigate the above association in a community-based Chinese population. METHODS: A total of 5027 men were included from the survey on prevalence for metabolic diseases and risk factors, which is a population-based study conducted from 2014 to 2016 in Eastern China. The estimated glomerular filtration rate (eGFR) was calculated according to the chronic kidney disease Epidemiology Collaboration equation. Low eGFR was defined as eGFR <60 mL·min -1 ·1.73 m -2 . RESULTS: After adjusting for age, smoking, metabolic factors, and testosterone, through increasing quartiles of SHBG, a significantly positive association between SHBG quartiles and eGFR was detected in men (Q1 vs. Q4, β -2.53, 95% confidence interval -3.89, -1.17, Ptrend < 0.001). Compared with the highest quartile of SHBG, SHBG in the lowest quartile was associated with 96% higher odds of low eGFR (odds ratio 1.96, 95% confidence interval 1.10, 3.48) in the model after full adjustment. According to the stratified analyses, the associations between a 1-standard deviation increase in serum SHBG and the prevalence of low eGFR were significant in men aged ≥60 years old, waist circumference <90 cm, diabetes (no), hypertension (yes), dyslipidemia (no), and nonalcoholic fatty liver disease (no). CONCLUSIONS Lower serum SHBG levels were significantly associated with lower eGFR and a higher prevalence of low eGFR in Chinese men independent of demographics, lifestyle, metabolic-related risk factors, and testosterone. Large prospective cohort and basic mechanistic studies are warranted in the future.
Humans ; Male ; Middle Aged ; China/epidemiology* ; Kidney/metabolism* ; Prospective Studies ; Sex Hormone-Binding Globulin/physiology* ; Testosterone ; Tomography, Emission-Computed, Single-Photon ; Glomerular Filtration Rate

ObjectiveTo explore the antagonistic effect of vitamin E (VE) on male reproductive toxicity induced by di-2-ethylhexyl phthalate (DEHP) in pubertal SD rats and its underlying mechanisms.

METHODSThirty 5-week-old male SD rats were randomly divided into five groups of equal number, corn oil control, low-dose (10 mg/kg/d), medium-dose (100 mg/kg/d) and high-dose DEHP exposure (500 mg/kg/d), and VE intervention (high-dose DEHP + VE ［100 mg/kg/d］), and treated respectively for 30 successive days. At 3 days after treatment, the testes of the animals were harvested for determination of the oxidative stress index, serum reproductive hormone levels, cauda epididymal sperm parameters, and expressions of cell apoptosis-related genes and proteins.

RESULTSCompared with the control group, the rats of the medium- and high-dose DEHP groups showed significant decreases in the levels of such serum reproductive hormones as follicle-stimulating hormone (FSH), luteinizing hormone (LH) and testosterone (T), sperm parameters as average path velocity (VAP), straight line velocity (VSL), curvilinear velocity (VCL), straightness (STR), linearity (LIN) and wobble (WOB), and the activities of superoxide dismutase (SOD) and glutathione peroxide (GSH-Px), but significant increases were observed in the latter two groups in the content of malondialdehyde (MDA)(［3.32±0.87］ nmol/mg pro vs ［2.13±0.49］ nmol/ mg pro), mRNA expressions of Bad, Bax, Cytochrome C, Caspase-3 and the Bax/Bcl-2 ratio, and protein expressions of Cytochrome C and Caspase-3. In comparison with the high-dose DEHP group, the VE intervention group exhibited remarkably increased serum LH and T levels, sperm VAP, VSL, VCL, STR and WOB, and activities of SOD and GSH-Px, but markedly decreased mRNA expressions of Bad, Bax, Cytochrome C, Caspase-3 and the Bax/Bcl-2 ratio as well as the protein expressions of Cytochrome C and Caspase-3 in the testis tissue (P<0.05).

CONCLUSIONSExposure to DEHP induces androgen secretion disorders, causes oxidative damage to the testicular tissue, activates the mitochondrial apoptosis pathway in the testis, and ultimately reduces the quality of epididymal sperm, while VE can protect the rat testis from DEHP-induced reproductive toxicity.

Animals ; Antioxidants ; pharmacology ; Apoptosis ; genetics ; Autophagy-Related Protein 5 ; metabolism ; Caspase 3 ; metabolism ; Diethylhexyl Phthalate ; antagonists & inhibitors ; Epididymis ; Follicle Stimulating Hormone ; blood ; Luteinizing Hormone ; blood ; Male ; Malondialdehyde ; metabolism ; Mitochondria ; drug effects ; Oxidative Stress ; drug effects ; Oxidoreductases ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Reproduction ; Spermatozoa ; drug effects ; physiology ; Superoxide Dismutase ; metabolism ; Testis ; drug effects ; Testosterone ; blood ; Vitamin E ; pharmacology

OBJECTIVETo investigate the effect of laparoscopic sleeve gastrectomy(LSG) on sex hormone in male patients with severe obesity.

METHODSRetrospective analysis was performed in 31 male patient with severe obese [body mass index(BMI) ≥28 kg/m, obesity group] who underwent LSG in Shanghai Tenth People's Hospital of Tongji University from December 2012 to May 2016. The anthropometric parameters(weight, BMI, waist circumference, hip circumference, waist-hip ratio, body fat percentage), glucose metabolic indices [fasting plasma glucose(FPG), fasting insulin (FINS), glycosylated hemoglobin (HbA1c), homeostasis model assessment-insulin resistance index(HOMA-IR)], and sex hormone parameters [estradiol(E2), total testosterone (TT), follicle-stimulating hormone (FSH) and luteinizing hormone (LH)] were collected preoperatively and 1, 3, 6 months postoperatively. In addition, 31 healthy male volunteers with normal BMI were consecutively recruited in this study as control group. The above-mentioned parameters were also determined in control group. Changes of these variables before and after surgery were analyzed. Pearson method was used to analyze the correlation of TT with anthropometric parameters and glucose metabolic indices before and after surgery.

RESULTSThe average age of patients in obesity and control group was (32.9±9.7) (18 to 56) years and (30.7±8.9) (18 to 49) years. Compared to the control group, obesity group had significantly higher anthropometric parameters and glucose metabolic indices before surgery (all P<0.05). In obesity group, the anthropometric and glucose metabolic indices significantly decreased at 1 to 6 months after surgery compared to those before surgery (all P<0.05). At 1 month after surgery, the anthropometric parameters and glucose metabolic indices in obesity group were significantly higher than those in control group (all P<0.05). At 3, and 6 months after surgery, there were no significant differences in glucose metabolic indices between obesity and control group (all P>0.05), while the anthropometric parameters in obesity group were still significantly higher than those in control group(all P<0.05). The sex hormone parameters in control and obesity group before surgery were as follows: E2: (100.2±23.5) pmol/L and (129.2±81.9) pmol/L; TT: (18.0±4.9) nmol/L and (8.4±4.5) nmol/L; FSH: (4.5±3.1) IU/L and (4.3±2.5) IU/L; LH: (4.4±1.7) IU/L and (5.3±2.6) IU/L. Compared to control group, the TT level of obese patients before surgery significantly decreased(P=0.000), while no significant differences were observed in the levels of E2, FSH, and LH(all P>0.05). The TT levels were significantly increased at 1, 3, 6 months after surgery[(13.1±7.0), (13.6±5.7), (21.0±19.3) nmol/L, respectively, all P<0.05] and the E2 level was significantly decreased at 6 months after surgery [(91.4±44.9) pmol/L, P<0.05], while no significant differences were observed at 1 and 3 months after surgery (all P>0.05). Furthermore, the FSH and LH levels did not exhibit significant change at 1, 3, and 6 months after surgery compared to those before surgery (all P>0.05). At 1 month after surgery, no significant correlations were examined in the change value of TT levels (▹TT) with the changes of BMI(▹BMI), FPG(▹FPG), FINS(▹FINS), HOMA-IR(▹HOMA-IR), and E2(▹E2) (all P>0.05). At 3 months after surgery, ▹TT was negatively correlated with ▹BMI (r=-0.441, P=0.015), ▹FINS (r=-0.375, P=0.041), and ▹HOMA-IR(r=-0.397, P=0.030), but not correlated with ▹FPG and ▹E2 (all P>0.05). At 6 months after surgery, ▹TT was negatively correlated with ▹BMI(r=-0.510, P=0.018) and ▹HOMA-IR (r=-0.435, P=0.049), but not correlated with ▹FPG, ▹FINS and ▹E2 (all P>0.05).

CONCLUSIONSMale severe obese patients are accompanied with abnormal sex hormone levels. LSG has a significant effect on weight loss and blood glucose improvement, and may ameliorate the sex hormone unbalance by improving the insulin resistance in men with severe obesity.

Adult ; Bariatric Surgery ; Blood Glucose ; physiology ; Body Mass Index ; Body Weights and Measures ; China ; Estradiol ; blood ; physiology ; Fasting ; blood ; Follicle Stimulating Hormone ; blood ; physiology ; Follow-Up Studies ; Gastrectomy ; Glycated Hemoglobin A ; physiology ; Humans ; Insulin ; blood ; physiology ; Insulin Resistance ; physiology ; Luteinizing Hormone ; blood ; physiology ; Male ; Obesity, Morbid ; surgery ; Retrospective Studies ; Testosterone ; blood ; physiology ; Treatment Outcome ; Weight Loss ; physiology

Objective: To investigate the relationship between the serum anti-Müllerian hormone (AMH) level and semen parameters. METHODS: We collected the data about 726 outpatients at the Male Infertility Clinic of Jinling Hospital from September 2015 to November 2016, including 72 with non-obstructive azoospermia, 123 with oligospermia, and 531 with normal sperm concentration. We obtained the semen volume, total sperm count, sperm concentration, sperm motility, the percentages of progressively motile sperm (PMS) and morphologically normal sperm (MNS), and the levels of serum AMH, inhibin B (INH-B), total testosterone (TT) and follicle - stimulating hormone (FSH) of the patients, analyzed the correlation of the serum AMH level with the other parameters, and compared the AMH level among different groups. RESULTS: The serum AMH level was found to be correlated positively with the total sperm count (r = 0.227, P <0.001), sperm concentration (r = 0.215, P <0.001), sperm motility (r = 0.111, P = 0.003), the percentage of PMS (r = 0.120, P = 0.001), and the levels of INH-B (r = 0.399, P <0.001) and TT (r = 0.184, P = 0.002), negatively with the FSH level (r = －0.283, P <0.001), but insignificantly with age, time of abstinence, semen volume, and the percentage of MNS (P >0.05). There was a statistically significant difference in the serum AMH level among the patients with non-obstructive azoospermia, oligozoospermia, and normal sperm concentration (［6.33 ± 4.26］ vs ［8.26 ± 3.98］ vs ［9.8 ± 5.19］ ng/ml, P <0.001). CONCLUSIONS Serum AMH is a biomarker reflecting the function of Sertoli cells and its level is significantly correlated with sperm concentration and motility, suggesting that AMH may be involved in spermatogenesis and sperm maturation.
Anti-Mullerian Hormone ; blood ; Azoospermia ; blood ; Biomarkers ; blood ; Follicle Stimulating Hormone ; blood ; Humans ; Inhibins ; blood ; Male ; Oligospermia ; blood ; Semen ; Semen Analysis ; Sertoli Cells ; physiology ; Sperm Count ; Sperm Motility ; Spermatogenesis ; Spermatozoa ; Testosterone ; blood

Objective: To investigate whether androgens can regulate the expression of eNOS in rat corpus cavernosum through AKT3, PIK3CA, CALM, and CAV1 and influence erectile function. METHODS: Thirty-six 8-week-old male SD rats were randomly divided into groups A (4-week control), B (6-week control), C (4-week castration), D (6-week castration), E (4-week castration + testosterone replacement), and F (6-week castration + testosterone replacement). Both the testis and epididymis were removed from the rats in groups C, D, E and F, and on the second day after surgery, the animals of groups E and F were subcutaneously injected with testosterone propionate at 3 mg per kg of the body weight qd alt while all the others with isodose oil instead. At 4 weeks (for groups A, C and E) and 6 weeks (for groups B, D and F) after treatment, we detected the maximum intracavernous pressure (ICPmax), the mean carotid arterial pressure (MAP) and their ratio (ICPmax/MAP), measured the level of serum testosterone (T), and determined the expressions of eNOS, P-eNOS, AKT3, PIK3CA, CALM and CAV1 in the corpus cavernosum by Western blot and immunohistochemistry. RESULTS: No statistically significant differences were observed in the body weight and MAP among different groups. The serum T level and ICPmax/MAP were remarkably lower in groups C and D than in the other four groups (P<0.01) as well as in groups E and F than in A and B (P<0.05) but exhibited no significant differences either between E and F or between A and B. Immunohistochemistry showed that eNOS and P-eNOS were mainly expressed in the vascular endothelial cell membrane and cavernous vascular lumen, while AKT3, PIK3CA, CALM and CAV1 chiefly in the vascular endothelial cell cytoplasm and membrane, with a few in the smooth muscle cells. Western blot analysis manifested that the expressions of eNOS, P-eNOS, AKT3, PIK3CA, CALM and CAV1 were markedly lower in groups C and D than in A, B, E and F (P<0.01) as well as in D than in C (P<0.05) but those in groups E and F did not showed any significant difference from those in A and B, nor E from F or A from B. CONCLUSIONS Androgens can improve erectile function by upregulating the expressions of AKT3, PIK3CA, CALM and CAV1 protein molecules and activating eNOS after its phosphorylation, though the exact molecular mechanisms are yet to be further studied.
Animals ; Blood Pressure ; Blotting, Western ; Caveolin 1 ; metabolism ; Class I Phosphatidylinositol 3-Kinases ; metabolism ; Erectile Dysfunction ; Hormone Replacement Therapy ; Male ; Monomeric Clathrin Assembly Proteins ; metabolism ; Myocytes, Smooth Muscle ; Nitric Oxide Synthase Type III ; metabolism ; Orchiectomy ; Penile Erection ; physiology ; Penis ; enzymology ; metabolism ; Proto-Oncogene Proteins c-akt ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Testosterone Propionate ; administration & dosage

Objective: To investigate the effect of aerobic exercise on the spermatogenic function of male rats and screen out differentially expressed proteins related to spermatonesis-regulation by proteomic analysis. METHODS: We randomly divided 24 SD male rats into groups A (non-exercise control), B (exercise), and C (weight-bearing exercise), those in the latter two groups made to swim for 60 minutes a day and those in group C bearing a load 3% of the body weight, both 6 times a week for 9 weeks. At 24 hours after the last exercise, we obtained the sperm count, measured the levels of such serum reproductive hormones as testosterone (T), luteotrophic hormone (LH), follicle-stimulating hormone (FSH), and gonadotrophin-releasing hormone (GnRH), and employed isobaric tags for relative and absolute quantitation (iTRAQ)-based proteomic analysis of the testicular tissue. RESULTS: Compared with group A, group C showed significant increases in sperm concentration (［2.12 ± 0.43］ vs ［3.54 ± 0.52］ ×10⁶/ml, P <0.01) and the levels of serum LH (［35.99 ± 2.90］ vs ［38.96 ± 1.34］ IU/L, P <0.01) and T (［19.99 ± 0.25］ vs ［21.36 ± 0.53］ nmol/L, P <0.01), but no statistically significant differences in GnRH (［623.95 ± 41.44］ vs ［641.82 ± 42.78］ ng/L, P >0.05) and FSH (［20.49 ± 2.44］ vs ［22.29 ± 2.31］ IU/L, P >0.05). No significant changes were observed in sperm concentration or reproductive hormone levels in group B as compared with A. Group B exhibited obviously more mature sperm and cell layers in the seminiferous epithelium than group A. A total of 47 differentially expressed proteins were identified, of which 37 were up-regulated and the other 10 down-regulated. In addition, another 5 significantly differentially expressed proteins closely related to reproductive function were identified, including up-regulated Anx A1, GPX3, Rimbp3, and Dpy19l2 and down-regulated CYP17. Enrichment analysis showed that the differentially expressed proteins were mainly involved in extracellular matrix-receptor interaction, protein digestion and absorption, and focal adhesion pathways. CONCLUSIONS Proper-intensity exercise can improve the spermatogenic function of rats. Aerobic exercise promotes spermatogenesis mainly by up-regulating the expressions of the proteins related to the production and differentiation of spermatozoa.
Animals ; Follicle Stimulating Hormone ; blood ; Gonadotropin-Releasing Hormone ; blood ; Luteinizing Hormone ; Male ; Physical Conditioning, Animal ; methods ; Proteomics ; methods ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Reproduction ; Resistance Training ; methods ; Sperm Count ; Spermatogenesis ; physiology ; Spermatozoa ; Testis ; Testosterone ; blood

As more and more studies suggest that type 2 diabetes mellitus (T2DM) is closely related to male hypogonadism, people begin to pay more attention to the role of testosterone in the development of T2DM and the effect and safety of testosterone supplementary therapy. There is some controversy in randomized controlled studies and meta-analyses about the effects of testosterone supplementation on the blood glucose level, androgen deficiency symptoms, and cardiovascular diseases. This review focuses on the diagnosis of hypogonadism in T2DM males, differences in the therapeutic effects and safety of testosterone replacement among different studies, and rational use of testosterone supplementation for T2DM patients.
Androgens ; deficiency ; Blood Glucose ; Cardiovascular Diseases ; etiology ; Diabetes Mellitus, Type 2 ; etiology ; Hormone Replacement Therapy ; Humans ; Hypogonadism ; complications ; diagnosis ; drug therapy ; Male ; Meta-Analysis as Topic ; Randomized Controlled Trials as Topic ; Testosterone ; physiology ; therapeutic use