eNOS polymorphisms on male infertility: An updated systematic review and meta-analysis

BACKGROUND

This meta-analysis was performed to examine the association of 3 endothelial nitric oxide synthase (eNOS) gene polymorphisms with male infertility.

METHODS

The literature on the relation between the mutant of eNOS and male infertility before July 1, 2022, was conducted in Pubmed, Medline, and Web of Science. The search strategy is as follows: (eNOS OR ECNOS OR nitric oxide synthase 3 OR NOS3) AND (polymorphism OR mutation OR variation OR SNP OR genotype) AND (male infertility). Statistical analysis was performed with the web of MetaGenyo, Stata 12, trial sequential analysis 0.9Beta, and the web of GTEx.

RESULTS

Overall, 13 studies (26 case-controls) were included involving 6518 cases and 5461 controls for 3 polymorphisms (rs2070744, rs1799983, rs61722009) of eNOS. We found that eNOS rs2070744 was correlated with an increased risk of male infertility (C vs. T: odds ratio [OR], 1.48; 95% confidence interval [CI], [1.19-1.85]; CC vs. TT: OR, 2.59; 95% CI, [1.40-4.80]; CT vs. TT: OR, 1.17; 95% CI, [1.00-1.38]; CC vs. CT + TT: OR, 2.50; 95% CI, [1.35-4.62]; CC + CT vs. TT: OR, 1.41; 95% CI, [1.21-1.64]). And eNOS rs1799983 was correlated with an increased risk of male infertility (allele contrast T vs. G: OR, 1.41; 95% CI, [1.01-1.96]; P = .043; recessive model TT vs. TG + GG: OR, 2.00; 95% CI, [1.03-3.90]; P = .042). In the stratified analysis of rs61722009, we found Asians might be correlated with an increased risk of male infertility (4a vs. 4b: OR, 1.50; 95% CI, [0.94-2.38]; 4a4a vs. 4b4b: OR, 2.56; 95% CI, [0.70-9.38]; 4a4b vs. 4b4b: OR, 1.36; 95% CI, [0.87-2.13]; 4a4a vs. 4a4b + 4b4b: OR, 2.57; 95% CI, [0.91-7.30]; 4a4a + 4a4b vs. 4b4b: OR, 1.44; 95% CI, [0.87-2.40]).

CONCLUSION

The eNOS rs2070744 polymorphism and rs1799983 are associated with the risk of male infertility, and rs61722009 might be a risk factor for Asians.

iPSCs derived from infertile men carrying complex genetic abnormalities can generate primordial germ-like cells

Despite increasing insight into the genetics of infertility, the developmental disease processes remain unclear due to the lack of adequate experimental models. The advent of induced pluripotent stem cell (iPSC) technology has provided a unique tool for in vitro disease modeling enabling major advances in our understanding of developmental disease processes. We report the full characterization of complex genetic abnormalities in two infertile patients with either azoospermia or XX male syndrome and we identify genes of potential interest implicated in their infertility. Using the erythroblasts of both patients, we generated primed iPSCs and converted them into a naive-like pluripotent state. Naive-iPSCs were then differentiated into primordial germ-like cells (PGC-LCs). The expression of early PGC marker genes SOX17, CD-38, NANOS3, c-KIT, TFAP2C, and D2-40, confirmed progression towards the early germline stage. Our results demonstrate that iPSCs from two infertile patients with significant genetic abnormalities are capable of efficient production of PGCs. Such in vitro model of infertility will certainly help identifying causative factors leading to early germ cells development failure and provide a valuable tool to explore novel therapeutic strategies.

Association of nitric oxide synthase 3 gene rs1799983 G/T polymorphism with idiopathic asthenozoospermia in Iranian Azeri males: a case-control study

OBJECTIVES

Recently, oxidative stress (OS) has been described extensively as an important cause of men infertility. The nitric oxide synthase 3 (NOS3) gene expression involved in normal spermatogenesis regulation in testis. Several single nucleotide polymorphisms (SNPs) on NOS3 gene are reported in association with sperm function and spermatogenesis impairment in infertile men. In present study, we investigated association of NOS3 gene rs1799983 G/T polymorphism in Iranian Azeri male with idiopathic asthenozoospermia (AZS).

METHODS

In this case-control study, we collected 50 males with idiopathic AZS as a case group and 50 age and ethnically matched male as healthy controls from East Azerbaijan area, Iran. The case and control groups genotyping was performed using tetra-primer amplification refractory mutation system-polymerase chain reaction (Tetra-ARMS PCR) method.

RESULTS

Genotype frequency in AZS patients was 40% GG, 60% GT, and 0% TT, whereas in healthy controls were 60% GG, 30% GT, and 10% TT. Statistical analysis showed that the GT heterozygous genotype frequency of NOS3 gene rs1799983 G/T polymorphism in AZS patients was significantly more than healthy controls (p>0.05).

CONCLUSIONS

We demonstrated that NOS3 gene rs1799983 G/T polymorphism was associated with AZS in Iranian Azeri men. However, more studies on different geographic areas, races and ethnicities are required to determine exact role of NOS3 gene rs1799983 G/T polymorphism in idiopathic AZS.

Specialize and Divide (Twice): Functions of Three Aurora Kinase Homologs in Mammalian Oocyte Meiotic Maturation

The aurora kinases (AURKs) comprise an evolutionarily conserved family of serine/threonine kinases involved in mitosis and meiosis. While most mitotic cells express two AURK isoforms (AURKA and AURKB), mammalian germ cells also express a third, AURKC. Although much is known about the functions of the kinases in mitosis, less is known about how the three isoforms function to coordinate meiosis. This review is aimed at describing what is known about the three isoforms in female meiosis, the similarities and differences between kinase functions, and speculates as to why mammalian germ cells require expression of three AURKs instead of two.

[What the study of seminal fluid proteins in Drosophila tells us about the evolution of reproduction]

Decrease in male fertility observed in the past decades have involved sperm quantity and quality disorders. However, decrease in quality or quantity of seminal fluid may also trigger drastic reduction of female and also male fertility. The present paper documents on the composition of seminal fluid, the consequences on sperm cells and on the physiological and behavioral effects towards females. The work evidences the crucial role of seminal fluid in the postcopulatory interactions between the sexes and illustrates the selective effects in the male-female coevolution.