Effect of glutathione S-transferase gene polymorphisms on semen quality in patients with idiopathic male infertility

Association of GSTM1 Polymorphism and Redox Potential with Idiopathic Male Infertility

BACKGROUND

The aim of this case-control study is to investigate possible associations between GSTM1 polymorphism and redox potential with sperm parameters.

METHODS

The study group consisted of sperm samples from 51 infertile men according to the WHO guidelines. The control group included 39 samples from men with normal seminal parameters. DNA was extracted and genotyped for the detection of the GSTM1 polymorphism. An evaluation of the static redox potential (sORP) using the MiOXSYSTM system was conducted.

RESULTS

The frequency of the GSTM1-null genotype was higher in infertile male individuals (60.78%) than in the controls (41.03%) and was associated with a 2.228-fold increased risk for male infertility. Fertile controls carrying the GSTM1-null genotype presented a lower percentage of typical sperm morphology and lower slow progressive motility. An excess of redox potential was observed in infertile males compared to fertile ones. In the control group higher sORP values had a positive correlation with immotility percentage and a negative correlation regarding total motility. In the study group sORP values had a negative correlation with total count, concentration, and slow progressive motility.

CONCLUSIONS

The present study highlights that GSTM1 polymorphism and redox potential affect both fertile and in fertile males. Moreover, redox potential levels could be used as an additional indicator along with the routine semen analysis for a comprehensive screening between infertile and fertile men.

Dendrobium officinale polysaccharides improved reproductive oxidative stress injury in male mice treated with cyclophosphamide

Polysaccharides from Dendrobium officinale polysaccharides (DOPs) are the main bioactive components of Dendrobium officinale, which have the functions of antioxidation and immune regulation. However, it is not clear whether DOPs have any effect on the prevention of reproductive disorders induced by oxidative stress. The purpose of this study was to explore the protective effect of DOPs on reproductive oxidative stress injury in male mice and its possible mechanism. In this study, the mouse model of reproductive injury was established by intraperitoneal injection of cyclophosphamide (CTX). The reproductive function was evaluated by relative testicular mass, sperm parameters, and sex hormone levels. The oxidative stress level of male mice with reproductive injury treated with DOPs was analyzed by the levels of 8-hydroxydeoxyguanosine (8-OHdG), malondialdehyde (MDA), and nitric oxide (NO) in sperm. The expression of follicle-stimulating hormone receptor (FSHR) mRNA, androgen-binding (ABP) mRNA, and c-kit mRNA was detected by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) to explore its mechanism. After CTX administration, the sperm density, sperm motility, normal sperm morphology, and sex hormone levels in mice were significantly lower than those in the control group (P < 0.05). At the same time, the expression of p53 protein was upregulated, and the expression of Bcl-2 protein was downregulated (P < 0.05). In addition, the expression of FSHR and ABP mRNA on Sertoli cells was also significantly inhibited (P < 0.05). DOPs can effectively reduce the oxidative stress injury of testicular tissue. After DOP treatment, the sperm quality and sex-related hormone levels of mice were significantly improved and positively correlated with the dose of DOPs (P < 0.05). Administration of DOPs can reduce the damage caused by oxidative stress by reducing the level of oxidative stress, improving the hormone environment in testes, and regulating the expression of specific genes in Sertoli cells and spermatogenic cells.

Oxidative Stress Markers and Sperm DNA Fragmentation in Men Recovered from COVID-19

SARS-CoV-2 negatively affects semen characteristics, impairs various biochemical processes in seminal fluid and within spermatogenic cells ultimately leading to male fertility decline. However, the distinct mechanisms, in particular, the role of oxidative stress on the consequences of coronavirus infection, have not been well investigated, which is the purpose of the present study. The standard semen parameters, its pro- and antioxidant system state, as well as the level of sperm DNA fragmentation, were assessed in 17 semen samples of men five months after the coronavirus infection and in 22 age-matched control patients. We determined that the DNA fragmentation rate negatively correlated with the period after coronavirus recovery, as well as seminal fluid superoxide dismutase activity and uric acid level. It was demonstrated that COVID-19 is not always associated with increased DNA fragmentation, allowing them to be considered as two independent factors. Thus, the most significant changes were noted in the samples of men after COVID-19 and abnormal TUNEL results: increased round cell number, decreased seminal fluid's nitrotyrosine level, and total antioxidant capacity and Zn, as well as an increased 8-hydroxy-2'-deoxyguanosine level within spermatozoa. The data obtained indicate that increased DNA fragmentation and diminished semen quality in men can be the result of an imbalance in semen pro- and antioxidant components after COVID-19.

Organochlorine pesticide exposures, metabolic enzyme genetic polymorphisms and semen quality parameters among men attending an infertility clinic

The associations of organochlorine pesticides (OCPs) with semen quality from human studies are conflicting, and also it is largely unknown whether the associations are modified by genetic polymorphisms. We aimed to evaluate the associations between serum concentrations of 18 OCPs and semen quality among 387 Chinese men, and further to examine the modifying effects by genetic polymorphisms in cytochrome P450 (CYP2E1) and glutathione S-transferase (GSTT1). Multivariable linear regressions were used to evaluate the relationships between serum OCP concentrations and semen quality, and the role of CYP2E1 and GSTT1 polymorphisms in modifying the associations were assessed. Multiple testing was adjusted using the false discovery rate (FDR). We observed that men with detectable concentrations of serum ɤ-HCH had a decrease in sperm motility of 7.07% (95% CI: -10.9%, -3.24%) compared to those with undetectable concentrations (FDR-P value = 0.02). Men with TT of CYP2E1 rs 915906 genotypes had higher median concentrations of serum dieldrin compared with those with CT/CC of CYP2E1 rs 915906 genotypes. There were interactions between CYP2E1 and GSTT1 polymorphisms and certain OCPs namely ɤ-HCH, δ-HCH, dieldrin, endosulfan I, and endrin aldehyde on semen quality. For example, elevated dieldrin levels in relation to decreased sperm concentration, sperm count, and sperm motility were only observed among men with CC of CYP2E1 rs2031920 genotypes (all P_interaction < 0.05). However, these interactions were not statistically significant after the FDR adjustment. Our results suggested that CYP2E1 and GSTT1 polymorphisms may modify the effects of OCP exposures on semen quality. Due to the relatively small size samples, further investigation is warranted to confirm the findings.