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Di-(2-ethylhexyl) phthalate is representative of Phthalate esters (PAEs), which is one of the most widely used plasticizer and known to act as a reproductive toxicant. However, little is known about the toxicity and pathological process of DEHP exposure in male reproductive system in terms of different concentrations and time points. In this study, peripubertal male Sprague Dawley rats were continually exposed to different DEHP doses (100 mg/kg, 500 mg/kg, and 900 mg/kg) and periods (7 days, 14 days, 21 days, 28 days, and 35 days) during critical periods for sexual maturity. The reproductive parameters have been investigated, including testicular morphology, serum testosterone level, and testicular P450scc, 3β-HSD, and PCYP17 levels. We observed disarrangement of testicular spermatogenic epithelium coupled with decrease of serum testosterone, testicular P450scc, 3β-HSD, and PCYP17 levels, and these changes were more obvious with increase of both the exposure time and dosage. Then trend of the time-dose response to DEHP exposure and the pathological process in germ cells were estimated. The results of this study suggested that DEHP exposure could affect the male reproductive system and the degree of adverse effect depended on the dose and extent of exposure.

Background Controversy remains despite several studies have discussed the role of bariatric surgery in improving male’s sexual function. This study aims to evaluate the efficacy of bariatric surgery in promoting male’s erectile function. Methods PubMed, EMbase, The Cochrane Library, CNKI and Clinical Trails.gov were searched from database inception to May 2019. The language of publication was limited in English. The International Index of Erectile Function (IIEF) score and Brief Male Sexual Function Inventory (BSFI) score were set as the primary outcome. Results Eleven studies with a total of 370 patients were enrolled in this meta-analysis. The results showed significant improvement in the IIEF score (erectile function: MD = 5.33, 95% CI 4.12–6.54; intercourse satisfaction: MD = 2.57, 95% CI 1.19–3.94; orgasmic function: MD = 0.50, 95%CI 0.60–0.94; overall satisfaction: MD = 1.67, 95% CI 0.78–2.56; sexual desire: MD = 1.27, 95% CI 0.61–1.93; total erectile function: MD = 7.21, 95% CI 4.33–10.10) and the BSFI score (erection: MD =2.53, 95% CI 2.39–2.67; ejaculation: MD = 1.40, 95% CI 1.28–1.51; desire: MD =1.40, 95% CI 1.32–1.49; problem assessment: MD = 2.20, 95% CI 2.06–2.34; sexual satisfaction: MD = 0.70, 95% CI 0.60–0.76) in obese individuals after bariatric surgery. Conclusions This systematic review and meta-analysis indicated that bariatric surgery could be effective in promoting males’s sexual function for obese individuals.

To evaluate the relationship between the aryl hydrocarbon receptor (AHR) rs2066853 gene polymorphism and the risk of male infertility. PubMed, Embase, Web of Science, and Chinese National Knowledge Infrastructure (CNKI) were searched for relevant case–control studies up to 31 July 2019. Odds ratio (OR) and 95% confidence interval (95% CI) were used to assess the strength of associations. Finally, seven case–control studies involving 1247 cases and 1762 controls were included in this meta-analysis. The pooled results showed that there was no significant association between AHR rs2066853 gene polymorphism and male infertility risk (A vs. G: OR = 1.08, 95% CI = 0.83–1.39; AA vs. GG: OR = 1.16, 95% CI = 0.65–2.04; AA vs. GA + GG: OR = 1.17, 95% CI = 0.66–2.07; AA + GA vs. GG: OR = 0.99, 95% CI = 0.85–1.15). Subgroup analysis by ethnicity showed the same result. However, significant association was found between AHR rs2066853 gene polymorphism and male infertility risk in oligoasthenotspermia (A vs. G: OR = 2.52, 95% CI = 1.72–3.70). In conclusion, our meta-analysis indicated that AHR rs2066853 gene polymorphism might be associated with an increased susceptibility to oligoasthenotspermia.

The association of genetic variants and congenital bilateral absence of the vas deferens (CBAVD) has been well acknowledged. By contrast, the link between nonobstructive azoospermia (NOA) or oligospermia and alterations in the cystic fibrosis transmembrane conductive regulator (CFTR) remains inconclusive. To clarify the problem, a meta-analysis was performed out after systematically searching Pubmed, Web of Science, Embase and the Chinese national knowledge infrastructure (CNKI) database. As we know, the ∆F508 and IVS8-5T gene mutations are the most studied genetic variants in CFTR gene. We reviewed the data from male patients who underwent the aforementioned genetic test. Our study revealed that the IVS8-5T mutation may be positively associated with the risk of nonobstructive male infertility (odds ratio (OR) 1.69; 95% CI: 1.12-2.55). This association strengthened when concerning NOA (OR: 2.62; 95% CI: 1.49-4.61). However, the ∆F508 mutation seemed to be a smaller contributing factor to this risk (OR: 1.63; 95% CI: 0.86-3.08). Our study aims to clarify the association between the ∆F508 and IVS8-5T gene mutations and nonobstructive male infertility. Therefore, screening for the IVS8-5T mutation in the CFTR gene may be recommended for men with NOA or severe oligozoospermia seeking assisted reproductive technology (ART).

To evaluate the association between the SPO11 gene C631T polymorphism and the risk of male infertility. We conducted a search on PubMed, Embase, Web of Science, Chinese National Knowledge Infrastructure (CNKI), China biology medical literature database (CBM), VIP, and Chinese literature database (Wan Fang) on 31 March 2016. Odds ratio (OR) and 95% confidence interval (95%CI) were used to assess the strength of associations. A total of five studies including 542 cases and 510 controls were involved in this meta-analysis. The pooled results indicated that the SPO11 gene C631T polymorphism was significantly associated with increased risk of male infertility (TT + CT vs. CC: OR = 4.14, 95%CI = 2.48–6.89; CT vs. CC: OR = 4.34, 95%CI = 2.56–7.34; T vs. C: OR = 4.35, 95%CI = 2.58–7.34). Subgroup analysis of different countries proved the relationship between SPO11 gene C631T polymorphism and male infertility risk in Chinese, but not in Iranian peoples. In conclusion, this study suggested that SPO11 gene C631T polymorphism may contribute as a genetic factor susceptible to cause male infertility. Furthermore, more large sample and representative population-based cases and well-matched controls are needed to validate our results.

To evaluate the association between TP53 codon72 polymorphism and male infertility risk. We conducted a search on Medline, Embase, Web of Science and CNKI up to April 30, 2017. Odds ratio (OR) and 95% confidence interval (95% CI) were used to assess the strength of the association. Seven studies including 1,818 cases and 2,278 controls met the inclusion criteria. The pooled results indicated that no significant association was observed between TP53 codon72 polymorphism and male infertility risk (G versus C: OR = 1.11, 95%CI = 0.94-1.32; GG versus CC: OR = 1.26, 95%CI = 0.90-1.78; GG versus GC+CC: OR = 1.16, 95%CI = 0.90-1.49; GG+GC versus CC: OR = 1.15, 95%CI = 0.88-1.49). In the subgroup analysis by ethnicity, significant association was observed between TP53 codon72 polymorphism and male infertility risk in non-Chinese (G versus C: OR = 1.47, 95%CI = 1.14-1.89), but not in Chinese population (G versus C: OR = 1.03, 95%CI = 0.87-1.22). In conclusion, this study suggested that TP53 codon72 polymorphism might be associated with an increased susceptibility to male infertility in non-Chinese population, but not in Chinese population. Studies with larger sample sizes and representative population-based cases and well-matched controls are needed to validate our results.

Background Methylenetetrahydrofolate reductase gene (MTHFR C677T and A1298C) and methionine synthase gene (MS A2756G) polymorphisms have shown an association with male infertility risk in several ethnic populations. Although several studies have evaluated these associations in Chinese populations, their small sample sizes and inconsistent outcomes have prevented strong conclusions. Therefore, the present meta-analysis was performed with published studies to evaluate the associations of the three single nucleotide polymorphisms (SNPs) and male infertility in a Chinese population. Methods We conducted a search of PubMed, Embase, Web of Science, Chinese National Knowledge Infrastructure (CNKI), China biology medical literature (CBM), VIP, and Chinese literature (Wan Fang) databases up to May 31, 2016. Odds ratios (ORs) and 95% confidence intervals (95%CIs) were used to assess the strength of associations with a random-effect model or a fixed-effect model based on the heterogeneity analysis results. Sensitivity analysis was used to confirm the reliability and stability of the meta-analysis. Results A total of nine studies, including 1,713 cases and 1,104 controls, were included in the meta-analysis. The pooled results indicated that the MTHFR C667T polymorphism was significantly associated with increased risk of male infertility in the Chinese population in the allele model (T vs. C: OR = 1.47, 95%CI = 1.32–1.63), the dominant model (TT + CT vs. CC: OR = 1.51, 95%CI = 1.30–1.77), the additive model (TT vs. CC: OR = 2.08, 95%CI = 1.68–2.58) and the recessive model (TT vs. CT+CC: OR = 1.58, 95%CI = 1.31–1.90), whereas the MTHFR A1298C and MS A2756G polymorphisms were not risk factors. There was no significant heterogeneity in any genotype contrasts among the studies. The sensitivity analysis indicated that the results of this meta-analysis were relatively stable. Conclusion This study suggests that the MTHFR C667T polymorphism may contribute to the genetic susceptibility to male infertility in the Chinese population, whereas MTHFR A1298C and MS A2756G polymorphisms may be unrelated to male infertility. Studies with larger sample sizes and representative population-based cases and well-matched controls are needed to validate our results.