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*

OBJECTIVETo investigate the expression of 17 beta-hydroxysteroid dehydrogenase type 1 (17β-HSD1) in the kidney of rats and explore the capacity of the kidney for synthesizing sex hormones.

METHODSThe expressions of 17-HSD1 and sex hormones were detected by Western blotting and radioimmunoassay in rat renal cells in primary cultured for 24 and 48 h in the presence or absence of follicle-stimulating hormone (FSH) and luteinizing hormone (LH).

RESULTSAfter cell culture for 24 h, the primary rat renal cells expressed a low level of 17β-HSD1 (0.1843±0.076), which increased to 1.6651±0.044 (P<0.01) in response to co-stimulation by FSH and LH. Low levels of estradiol, progesterone and testosterone were also detected in rat renal cells (3.30±3.78, 62.60±12.33, and 22.12±3.36, respectively), and co-stimulation of FSH and LH significantly increased their levels to 8.50±2.64, 117.80±9.79, and 45.04±4.39, respectively (P<0.05). The levels of these hormones showed no significant differences between cells cultured for 24 h and 48 h (P>0.05).

CONCLUSIONThe rat renal cells express 17β-HSD1 and are capable of stably secreting sex hormones in response to co-stimulation with FSH and LH, suggesting the capacity of the rat kidneys for synthesizing sex hormones. These findings enrich the understanding of the endocrine function of the kidney.

17-Hydroxysteroid Dehydrogenases ; metabolism ; Animals ; Cells, Cultured ; Estradiol ; biosynthesis ; Follicle Stimulating Hormone ; pharmacology ; Kidney ; enzymology ; Luteinizing Hormone ; pharmacology ; Progesterone ; biosynthesis ; Rats ; Testosterone ; biosynthesis

The hepatocyte growth factor ( HGF) is a multifunctional growth factor, which produces multiple biological effects by binding to the c-Met acceptor. This article reviews the biological properties of HGF, particularly those correlated with male reproduction, including its abilities to promote testis embryonic development, spermatogenesis, and testosterone synthesis of Leydig cells. HGF may provide a new insight into the treatment of male hypogonadism and infertility.
Embryonic Development ; Hepatocyte Growth Factor ; physiology ; Humans ; Leydig Cells ; metabolism ; Male ; Proto-Oncogene Proteins c-met ; metabolism ; Reproduction ; physiology ; Spermatogenesis ; physiology ; Testis ; embryology ; Testosterone ; biosynthesis

OBJECTIVETo study the expression of the receptor for advanced glycation end products (RAGE) and the inhibitory effect of advanced glycation end products (AGEs) on testosterone production in rat Leydig cells.

METHODSRat Leydig cells were primarily cultured and the expression of RAGE in the Leydig cells was detected by RT-PCR and immunofluorescence staining. The Leydig cells were treated with AGEs at the concentrations of 25, 50, 100 and 200 microg/ml, respectively, and the testosterone content was determined by ELISA.

RESULTSRT-PCR and immunofluorescence staining exhibited the expression of RAGE in the rat Leydig cells. AGEs remarkably suppressed hCG-induced testosterone production in the Leydig cells in a concentration-dependent manner in the 50, 100 and 200 microg/ml groups as compared with the control (P < 0.01).

CONCLUSIONRAGE exists in rat Leydig cells and AGEs can significantly inhibit the secretion of testosterone in primarily cultured rat Leydig cells.

Animals ; Cells, Cultured ; Enzyme-Linked Immunosorbent Assay ; Glycation End Products, Advanced ; pharmacology ; Leydig Cells ; metabolism ; radiation effects ; Male ; Rats ; Receptor for Advanced Glycation End Products ; Receptors, Immunologic ; biosynthesis ; Reverse Transcriptase Polymerase Chain Reaction ; Testosterone ; biosynthesis

The steroidal enzyme cytochrome P45017alpha catalyzes the conversion of progesterone and pregnenolone into androgens, androstenedione and dehydroepiandrosterone, respectively, the direct precursors of estrogens and testosterone. Dihydrotestosterone is the principal active androgen in the prostate, testosterone is also an active stimulant of the growth of prostatic cancer tissue. Inhibition of this enzyme as a mechanism for inhibiting androgen biosynthesis could be a worthwhile therapeutic strategy for the treatment of PCA. In this paper, four categories of steroidal inhibitors of cytochrome P45017alpha will be reviewed, a diverse range of steroidal inhibitors had been synthesized and shown to be potent inhibitors of P45017alpha.
Androstenedione ; biosynthesis ; Androstenes ; Androstenols ; chemical synthesis ; chemistry ; pharmacology ; Animals ; Antineoplastic Agents ; chemical synthesis ; chemistry ; pharmacology ; Dehydroepiandrosterone ; biosynthesis ; Dihydrotestosterone ; metabolism ; Enzyme Inhibitors ; chemical synthesis ; chemistry ; pharmacology ; Humans ; Male ; Molecular Structure ; Pregnenolone ; metabolism ; Progesterone ; metabolism ; Prostatic Neoplasms ; pathology ; Steroid 17-alpha-Hydroxylase ; antagonists & inhibitors ; Testosterone ; biosynthesis

3-Hydroxysteroid Dehydrogenases ; metabolism ; Animals ; Cadmium ; toxicity ; Cells, Cultured ; DNA ; drug effects ; DNA Damage ; Leydig Cells ; drug effects ; enzymology ; secretion ; Male ; Rats ; Testosterone ; biosynthesis ; secretion

OBJECTIVETo investigate the effects of Cox7a2 on the LH-induced testosterone production and the involved autophagy regulating signals in TM3 mouse Leydig cells.

METHODSThe Cox7a2-pEYFP-N1 fluorescent protein vector was constructed and transfected into TM3 mouse Leydig cells. The level of testosterone was determined by ELISA, and the effects of Cox7a2 on the expression of the steroidogenic acute regulatory protein (StAR) and the phosphorylation of the autophagy regulatory factor P70S6K were detected by Western blot.

RESULTSLH stimulation increased the StAR protein expression and testosterone production, while Cox7a2 decreased P70S6K phosphorylation, reduced StAR expression and consequently inhibited LH-induced testosterone biosynthesis in the TM3 Leydig cells.

CONCLUSIONCox7a2 inhibits testosterone production by decreasing the StAR protein expression, which might be at least in part related with the activation of autophagy in TM3 mouse Leydig cells.

Animals ; Autophagy ; Cells, Cultured ; Electron Transport Complex IV ; genetics ; Leydig Cells ; metabolism ; Luteinizing Hormone ; pharmacology ; Male ; Mice ; Phosphoproteins ; metabolism ; Phosphorylation ; Ribosomal Protein S6 Kinases, 70-kDa ; metabolism ; Testosterone ; biosynthesis

OBJECTIVETo investigate the functional and metabolic alterations in cultured insulin resistant ovary model in vitro, and to observe the effect of berberine (Ber, a Chinese medical monomer) in improving insulin resistance (IR).

METHODSOvary of mouse was cultured in vitro and treated by dexamethasone (Dex) to induce IR for establishing IR model ovary. The functional alteration in model ovary was assessed through detecting glucose and hormone levels in medium using RT-PCR, meanwhile, the expression of key molecules in insulin signal and steroid synthetic pathway were detected, and condition of IR improved by berberine was evaluated also.

RESULTS(1) The model ovary was made by Dex in dose- and acting time-dependent manner. After being treated by 300 nmol/L Dex for 48 h, the glucose uptake of ovary reduced from 9.05 +/- 0.75 mg/g to 2.48 +/- 0.29 mg/g (P < 0.05); it further decreased (from 9.59 +/- 1.74 mg/g to 1.94 +/- 0.19 mg/g, P < 0.01) under the stimulation of insulin, which proved that the IR model ovary was made successfully. Berberine significantly increased the glucose uptake of model ovaries (1.89 +/- 0.33 mg/g to 13.95 +/- 3.30 mg/g, P < 0.05). (2) As compared with control group, levels of testosterone (T) and androstenedione (A2) were higher, and levels of progesterone (P) and 17-hydroxyprogesterone (17-OHP) were lower significantly in the model. Berberine reversed the alternations of T, A2 and 17-OHP levels, but did not influence the level of P. (3) RT-PCR showed that the mRNA expressions of cytochrome 17-hydroxylase (CYP17) and mini-chromosome maintenance protein-2 (MCM-2) elevated, but extracellular regulated protein-1 (ERK-1), protein kinase B (AKT-2) and glycogen synthase kinase-3 (GSK-3beta) lowered in the medium after Dex inducing. Berberine treatment restored these molecular index obviously.

CONCLUSIONS(1) Dex could induce IR in mouse ovary, which might enhance the androgenic synthesis. (2) Berberine could alleviate the degree of IR and the androgen synthesis, indicating that the Chinese sensitizing agents has favorable therapeutic effect for the treatment of polycystic ovaries.

17-alpha-Hydroxyprogesterone ; metabolism ; Androstenedione ; biosynthesis ; Animals ; Berberine ; pharmacology ; Female ; In Vitro Techniques ; Insulin ; metabolism ; Insulin Resistance ; Mice ; Mice, Inbred Strains ; Ovary ; drug effects ; metabolism ; Polycystic Ovary Syndrome ; Progesterone ; biosynthesis ; Testosterone ; biosynthesis

OBJECTIVETo investigate the inhibitory mechanisms of testosterone (T) biosynthesis in rats exposed to dibutyl phthalate (DBP).

METHODSMale Wistar rats were randomly divided into five groups by weight, including 0.25, 0.50, 1.00, 2.00 g/kg DBP groups and corn oil control group, with 16 rats in each group. DBP was administered by gavage once a day. After 30 days exposure, eight rats in each group were killed and the others were killed after 15 days without DBP administration. The levels of T and glucocorticoid (GC) in serum were determined by radioimmunoassay. The expression levels of 11 beta-dedroxysteriod dehydrogenase (11 beta-HSD) mRNA and steroidogenesis acute regulatory protein (StAR) mRNA were determined by RT-PCR. The protein expression level of glucocorticoid receptor (GR) was investigated by Western blotting.

RESULTSDuring exposure period, in 1.00 and 2.00 g/kg DBP groups, the levels of T were (0.260 +/- 0.218) ng/ml and (0.260 +/- 0.342) ng/ml, the levels of GC were (13.470 +/- 5.661) ng/ml and (13.740 +/- 3.977) ng/ml, the levels of T and GC in control group were (1.045 +/- 1.222) ng/ml and (9.224 +/- 3.496) ng/ml. There were statistic differences between 1.00 and 2.00 g/kg DBP groups and control group (t(T) values were -2.295 and -2.295, t(GC) values were 2.159 and 2.296, respectively, P < 0.05). The expression level of StAR mRNA was significantly down-regulated in 1.00 and 2.00 g/kg DBP groups, while StAR/beta-Actin values were 0.657 +/- 0.060 and 0.407 +/- 0.033, and compared to control group (0.871 +/- 0.081), there was statistic difference (t values were -3.707 and -8.037, P < 0.05). In 1.00 and 2.00 g/kg DBP groups, the expression of 11 beta-HSD mRNA and the expression of GR protein were increased in DBP dose-dependent manner, while 11 beta-HSD/beta-Actin values were 0.538 +/- 0.138 and 0.988 +/- 0.133, and GR/beta-Actin were 0.785 +/- 0.106 and 0.956 +/- 0.076, respectively. There were statistic difference, as compared to the controls (0.285 +/- 0.106 and 0.275 +/- 0.035) (t(11 beta-HSD/beta-Actin) values were 2.829 and 7.860, t(GR/beta-Actin) values were 8.064 and 10.77, respectively, P < 0.05).Linear correlation and regression revealed that there were positive correlation between DBP dose and the expression levels of 11 beta-HSD mRNA and GR protein, with r values of 0.766 and 0.790, respectively. In post-exposure period, there were no statistic differences of all above index among DBP groups and control group.

CONCLUSIONDBP might inhibit T production in rats through GR mediation.

Animals ; Dibutyl Phthalate ; toxicity ; Glucocorticoids ; metabolism ; Male ; Rats ; Rats, Wistar ; Receptors, Glucocorticoid ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Testosterone ; biosynthesis ; blood

OBJECTIVETo investigate the effects of phytoestrogens (daidzein and genistein) on the testosterone production of rat Leydig cells and the possible mechanisms.

METHODSPrimary Leydig cells were obtained from 3-month old male SD rats using discontinuous Percoll density gradient centrifugation. The effects of phytoestrogens at various concentrations were evaluated by ELISA, with hCG as the positive control. The mRNA expression of P450 side-chain cleavage enzyme (P450scc) was analyzed by semi-quantitative RT-PCR.

RESULTSGenistein at 0.1 micromol/L obviously promoted the secretion of testosterone and upregulated the mRNA level of P450scc. At a higher concentration of 5 micromol/L, however, both daidzein and genistein significantly inhibited the testosterone production of Leydig cells (P > 0.05).

CONCLUSIONGenistein can promote the testosterone production of Leydig cells at a low concentration (0.1 micromol/L), but both daidzein and genistein can inhibit it at a higher concentration ( >5 micromol/L).

Animals ; Cells, Cultured ; Genistein ; pharmacology ; Isoflavones ; pharmacology ; Leydig Cells ; drug effects ; secretion ; Male ; Phytoestrogens ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Testosterone ; biosynthesis