RESUMEN
BACKGROUND: A notable proportion of idiopathic male infertility cases is accompanied by oligozoospermia; and yet, the molecular mechanisms of fertilization problem underlying this defect are still unclear. Epithelial cadherin has been involved in several calcium-dependent cell-to-cell adhesion events; however, its participation in gamete interaction has also not been fully investigated. OBJECTIVE: The aim was to investigate the changes in the expression of E-cadherin, based on the frequency of Single nucleotide polymorphisms in Nuclear Factor Kappa-B 1 and pre-mir-146a in oligospermic men. MATERIALS AND METHODS: In this case-control study, semen and blood samples of 131 oligospermic men as the case group and 239 fertile healthy men as the control group were analyzed. Variants single nucleotide polymorphisms rs28362491 and rs2910164 were performed using polymerase chain reaction-restriction fragment length polymorphism method and E-cadherin expression were determined by immunoprecipitation studies. RESULTS: ins/ins genotype of rs28362491 was determined as a risk factor for idiopathic oligospermia by 1.73 times (p=0.0218), whereas no significant differences were found between the groups concerning pre-mir-146a rs2910164 polymorphism (p=0.2274 in case of GC genotype and p=0.9052 in case of GG genotype). Combined genotype analysis results did not show any notable differences between the multiple comparisons of 28362491-rs2910164 in oligospermic men and control groups. In addition, E-cadherin expression of oligospermic men with ins/ins genotype was significantly lower than patients with del/ins genotype (p=0.0221). E-cadherin expression level was low in oligospermic men with respect to the control group in presence of ins/ins genotype of NFKB1 gene. CONCLUSION: These results suggest that ins allele prevents binding of surface proteins to spermatozoa, leading to a low affinity of sperm-oocyte interaction in oligospermic men.
RESUMEN
MiRNAs and NFKB1 are well-known immune response and inflammation regulators. MiRNA gene polymorphisms may affect miRNA biogenesis and function and, may thus, lead to changes in the expression of hundreds of genes such as NFKB1. The aim of this study was to investigate the association of Behcet's disease (BD) with NFKB1 rs28362491, pre-miRNA-146a rs2910164, and pre-miRNA-499 rs3746444 polymorphisms, as well as the analysis of their single and combined effects on its susceptibility in a Turkish population. These polymorphisms were analyzed by using the polymerase chain reaction-restriction fragment length polymorphism method in 100 BD patients and 145 healthy control subjects. The results were analyzed statistically using Pearson chi-square (χ(2)) test and Fisher's exact test (two sided). According to genotype analysis, the frequencies of ins/ins genotype and ins allele of rs28362491 were considerably higher in BD patients. Also, miRNA-499 rs3746444 homozygous (TT) genotypes exibited a significantly higher risk in patients with BD (odds ratios [OR]=3.0, 95% confidence intervals [95% CI]=1.284-7.007, p=0.017). Moreover, the frequency of T allele of rs3746444 was a risk factor for BD (OR=1.562, 95% CI=1.087-2.24, p=0.015). In addition, significant differences were found between the groups concerning miRNA-146a rs2910164 polymorphism. Homozygous CC genotype and C allele of rs2910164 polymorphism were found to be protective factors against BD. The results of the combined genotype analysis showed no notable differences between the multiple comparisons of rs28362491-rs2910164 and of rs28362491-rs3746444 in patients and control groups. Our data demonstrate that homozygous CC genotype and C allele of rs2910164 polymorphism are protective factors against BD, but rs3746444 and rs28362491 polymorphisms in miRNA-499 and in NFKB1 promoter are involved in the genetic susceptibility of BD. In addition, TT and ins/ins genotypes may influence certain proinflammatory cytokines and, may thus, play a role in the pathogenesis of BD.