Objective. This study evaluated the effects of obesity on the function of reproductive organs in male mice and the possible mechanism of male secondary hypogonadism (SH) in obesity.Methods. Ninety-six mice were randomly assigned to three groups: the control group, diet-induced obesity group, and diet-induced obesity resistant group for 8 weeks and 19 weeks. The effects of short- and long-term high-fat diet on the reproductive organs were determined by measuring sperm count and motility, relative testis weight, testosterone level, pathological changes and apoptosis of Leydig cells. Oxidative stress was evaluated by determining malondialdehyde, H₂O₂, NO levels, and GSH in testis tissues. CAT, SOD, GSH-Px and Nrf₂mRNA were measured by real-time PCR.Results. Short- and long-term high-fat diet decreased sperm count and motility, relative testis weight, testosterone level; decreased CAT, SOD, GSH-Px and Nrf₂mRNA expression; increased MDA, H₂O₂, NO and leptin levels; inhibited the activity of CAT and GSH-Px enzymes. Pathological injury and apoptosis of Leydig cells were found in testis tissue.Conclusions. Pathological damage of Leydig cells, oxidative stress in testis tissue, and high level of leptin may provide some evidence to clarify the mechanisms of male SH in obesity.

(1) Background: In recent decades, the prevalence of obesity has grown rapidly worldwide, thus causing many diseases, including male hypogonadism. Sulforaphane (SFN), an isothiocyanate compound, has been reported to protect the reproductive system. This research investigated the protective effect of SFN against obesity-induced impairment in the male reproductive system and explored the potential mechanism involved in mice. (2) Methods: One hundred thirty mice were divided into 5 groups (Control, DIO (diet-induced obesity), DIO + SFN 5 mg/kg, DIO + SFN 10 mg/kg, and DIO + SFN 20 mg/kg). The effects of SFN on the male reproductive system were determined based on the sperm count and motility, relative testes and epididymis weights, hormone levels, and pathological analyses. Oxidative stress was determined by measuring malondialdehyde (MDA), total antioxidant capacity (T-AOC), superoxide dismutase (SOD), glutathione (GSH), H₂O₂, catalase (CAT), and glutathione peroxidase (GSH-PX) levels. Protein expression of nuclear factor erythroid-2 related factor 2 (Nrf2), Kelch-like ECH-associated protein-1 (Keap1), Microtubule-associated protein light chain 3 (LC3), Beclin1, and P62 were determined by western blotting. (3) Results: High-fat diet (HFD)-induced obesity significantly decreased relative testes and epididymis weights, sperm count and motility, and testosterone levels but increased leptin and estradiol levels. SFN supplementation ameliorated these effects. Additionally, SFN administration inhibited the obesity-induced MDA accumulation and increased the SOD level. Western blot indicated that SFN had an important role in the downregulation of Keap1. Moreover, SFN treatment attenuated obesity-induced autophagy, as detected by LC3 and Beclin1. (4) Conclusions: SFN ameliorated the reproductive toxicity associated with obesity by inhibiting oxidative stress mediated by the nuclear factor erythroid-2 related factor 2/ antioxidant response element (Nrf2/ARE) signaling pathway and recovery of normal autophagy.

Objective. This study evaluated the effects of di‐(2‐ethylhexyl) phthalate (DEHP) and obesity on male reproductive organ function in male mice and the potential mechanism of male secondary hypogonadism (SH) in such mice. Methods. 140 mice were assigned to six groups for 12 weeks: normal, DEHP, DIO, DIO + DEHP low, DIO + DEHP middle, and DIO + DEHP high. The effects of DEHP and obesity upon the reproductive organs were determined by measuring sperm count and motility, relative testis and epididymis weight, hormone level, and pathological changes. Oxidative stress was evaluated by determining malondialdehyde, T‐AOC, SOD, GSH, H₂O₂, CAT, and GSH‐PX in testicular tissues. Nrf2 and Keap1 protein were measured by Western blotting. Results. DEHP and obesity reduced sperm count and motility, relative testis and epididymis weight, and testosterone level but increased the levels of MDA, H₂O₂, leptin, and estradiol. Pathological injury was observed in the testicular Leydig cells. Moreover, the activity of CAT, SOD, and GSH‐Px enzymes was inhibited. Nrf2 protein expression was reduced but that of Keap1 was increased. Conclusions. DEHP and obesity jointly caused damage to male productive function. Oxidative stress in testicular tissue, and a high level of leptin, may provide some evidence to clarify the mechanisms of male SH with DEHP and obesity.

The toxic effect of Polystyrene Microplastics (PS-MPs) on leydig cells were found in male mice, but the toxic mechanism was not clear. The PS-MPs exposure mice model and cell model were established in this study to explore the leydig cells toxic mechanism. In vivo study, the leydig cells toxicity in male mice was evaluated exposed to PS-MPs for 28 days. And found that the sperm density, mobility and testosterone (T) level decreased, and the sperm malformation rate and malondialdehyde level increased. PS-MPs exposure impaired the function of male reproduction. The results also showed that the levels of testosterone-producing proteins (StAR, P450scc,3β-HSD and CYP17A1) decreased, apoptosis signaling pathways (Bax/Bcl-2, Caspase-8 and Caspase-12) were activated and endoplasmic reticulum stress (GRP78/p-PERK/CHOP) occurred in male mice exposed to PS-MPs. In vitro study, TM3 cells (leydig cells) were treated with 50, 100 and 200 μg/mL of PS-MPs for 24 h. And we found that PS-MPs exposure reduced the cell viability and the level of T, increased reactive oxygen species (ROS) level in TM3 cells. PS-MPs exposure impaired the function of the leydig cells. Further testing revealed that PS-MPs could activate GRP78/p-PERK/CHOP pathway, aggrandized endoplasmic reticulum stress in the leydig cells, then increased apoptosis level, and induced testosterone synthase protein reduction. These could be reversed when exposed to ROS inhibitor or endoplasmic reticulum stress inhibitor. In conclusion, PS-MPs exposure induced the high level of ROS, activated the GRP78/p-PERK/CHOP signaling pathway, enhanced endoplasmic reticulum stress in leydig cells, then apoptosis level increased, which impaired the leydig cell function.