Glutathione-S-transferase-oxidative stress relationship in the internal spermatic vein blood of infertile men with varicocele

Genetic variants in varicocele-related male infertility: a systematic review and future directions

Genetic association studies (GAS) may have the capability to probe the genetic susceptibility alleles in many disorders. This systemic review aimed to assess whether an association exists between gene(s)/allelic variant(s), and varicocele-related male infertility (VRMI). This review included 19 GAS that investigated 26 genes in 1,826 men with varicocele compared to 2,070 healthy men, and 263 infertile men without varicocele. These studies focussed on candidate genes and relevant variants, with glutathione S-transferase gene being the most frequently studied (n = 5) followed by the nitric oxide synthase 3 (NOS3) gene (n = 3) and the phosphoprotein tyrosine phosphatase 1 gene (n = 2). In one study the genes for NAD(P)H quinone oxidoreductase 1, sperm protamine, human 8-oxoguanine DNA glycosylase 1, methylenetetrahydrofolate reductase, polymerase gamma, heat shock protein 90, mitochondrial DNA, superoxide dismutase 2, transition nuclear protein 1, and transition nuclear protein 2, were assessed. There is no clear indication that any of these polymorphisms are sturdily associated with VRMI. However, three studies established that the polymorphic genotype (GT + TT) for rs1799983 polymorphism of the NOS3 gene is more frequent in varicocele patients. Further endeavours such as standardising reporting, exploring complementary designs, and the use of GWAS technology are justified to help replicate these early findings.

Vitamins as primary or adjunctive treatment in infertile men with varicocele: A systematic review

OBJECTIVE

To investigate the usage and the efficacy of vitamins as primary or adjuvant treatment in infertile men with varicocele.

METHODS

A systematic search in PubMed, the Medical Literature Analysis and Retrieval System Online (MEDLINE) and Cochrane Library with the terms (varicocele) AND (vitamins) was performed. We searched for studies: a) reporting the administration of vitamins (individually or as part of a complex) in men with varicocele and infertility, b) primarily or adjuvant to invasive treatment, and c) reporting the impact on semen parameters and/or pregnancy rates. Exclusion criteria were animal, adolescent and non-English studies, grey literature and trials reporting abstracts only.

RESULTS

Seven studies were identified eligible for qualitative analysis. All studies were randomised except one (case series). Vitamins were administered dominantly as part of antioxidant complex and only two studies used vitamins (C and E, respectively) as sole agent. In two studies, vitamin monotherapy resulted in improvement in semen quality, but the effect on pregnancy rates is unknown. One study reported no efficacy of adjuvant multivitamin treatment after embolisation in terms of both semen quality and pregnancy rates. Finally, four studies reported a positive effect of vitamins on semen parameters after varicocelectomy, but the effect on pregnancy rates is conflicting; one study reported improved pregnancy rates with adjuvant treatment, two studies did not evaluate the pregnancy rates, and in one study the outcome was unclear due to missing data.

CONCLUSIONS

Vitamins have been used mostly as part of an antioxidant panel for the management of infertile men with varicocele. Most studies have found a positive impact on semen parameters in selected men with varicocele and infertility, as primary or adjuvant treatment. However, the clinical benefit of vitamins administration on pregnancy rate is under-evaluated and should be the target of future research.

Reduced sperm telomere length in individuals with varicocele is associated with reduced genomic integrity

Varicocele, defined as enlarged varicose veins in the scrotum, is the most common identifiable cause of male infertility. There are significant correlations between oxidative stress and varicocele-related infertility due to testicular hyperthermia, which can result in low sperm function. In addition, recent excessive oxidative stress can affect sperm telomere length and integrity of sperm DNA. Therefore, we assessed sperm telomere length as a potential marker of paternal genome integrity and leukocyte telomere length as an internal control (real-time PCR), along with sperm chromatin status (TUNEL and chromomycin A3 assay), and lipid peroxidation (Bodipy probe) in 18 infertile men with grade II or III varicocele, and 20 fertile men. Means of sperm parameters, sperm and leukocyte telomere length were significantly lower, while means of sperm DNA fragmentation, protamine deficiency, and lipid peroxidation were significantly higher in infertile men with varicocele compared to fertile men. Therefore, shortened telomere length in sperm and leukocytes is likely associated with increased oxidative stress related to the state of varicocele, which also accounts for increase in sperm DNA fragmentation. Thus, assessment of leukocyte telomere length could be taken as an indicator of antioxidant capacity in an individual, which also affects sperm function.

Effects of the oxidative stress and genetic changes in varicose vein patients

Background

Etiology of the varicose veins is still partly known. It has been proposed that varicose veins formation might be a cause of the oxidative stress and/or cause from genetical reasons.

Method

The levels of antioxidant defense system enzymes, superoxide dismutase, catalase, glutathione peroxidase, glutathione S-transferase, and an oxidative stress indicator, malondialdehyde, were measured in saphenous vein samples of varicose veins patients. Additionally, genetical polymorphism of glutathione S-transferase theta-1 has been studied.

Result

In this study, measurements revealed significant increase in catalase and malondialdehyde levels in the patient group, whereas superoxide dismutase and glutathione peroxidase and glutathione S-transferase enzyme activity and comparison of the null mutation frequency in the glutathione S-transferase theta-1 gene did not show a statistically significant difference.

Conclusion

We propose that the increase in catalase and malondialdehyde activities in our patient group may be related to each other. Increase in catalase levels, an antioxidant enzyme might be a compensatory response to the increase in malondialdehyde levels, an oxidative molecule.

The Role of Oxidative Stress, Selected Metals, and Parameters of the Immune System in Male Fertility

The aim of the study was to investigate the associations between standard semen parameters and the parameters reflecting oxidative stress intensity, antioxidant defense functions, levels of selected macro and trace elements, and parameters characterizing immune system function. The study group consisted of 103 fertile males. Based on semen volume, sperm concentration, total sperm count, and percentage of motile sperm at 1 hour postcollection, the individuals were divided into two equal groups—those with excellent (EX) semen quality and those with mediocre (ME) semen quality. The remaining measured parameters characterizing motility and the percentage of normal morphology were higher in the EX group than in the ME group; however, the seminal plasma pH did not differ between the examined groups. The phosphate level was 31% lower in the EX group than in the ME group, whereas there was a tendency toward a 25% lower level of Fe in the EX group than in the ME group (p = 0.064). The activities of enzymes involved in antioxidant defense, CuZn-SOD, CAT, and G6PD, were 14%, 63%, and 39%, respectively, higher in the EX group than in the ME group. However, the level of alpha-tocopherol was 32% lower in the EX group than in the ME group. The other measured parameters characterizing antioxidant defense and the parameters of oxidative stress intensity and immune system function were not significantly different. The value of seminal plasma pH is not related to the semen quality of fertile males. Higher fertility potential estimated based on standard semen parameters in fertile males is associated with lower levels of Fe and higher activities of some antioxidant enzymes.