Endothelial Nitric Oxide Synthase Polymorphisms and Erectile Dysfunction: A Meta-Analysis

Abstract

Introduction and Aims Erectile dysfunction (ED) is a frequent disorder in men and has a serious impact on the quality of the patient's life. Recent studies have examined the relationship between endothelial nitric oxide synthase (eNOS) polymorphisms and ED. However, the results remain inconclusive. The present study aimed to offer an actual view of estimating the correlation between eNOS polymorphisms and ED. Methods We performed a meta-analysis to estimate the association between eNOS polymorphisms and ED risk. Databases employed for data mining until December 1, 2014 included PubMed, Web of Science, and the Chinese National Knowledge Infrastructure. Two study investigators independently conducted a literature search and data extraction. Odds ratios (ORs) with 95% confidence intervals for the risk were calculated by using a random effects model or fixed effects model. Results A total of 20 studies in 13 publications were included in the meta-analysis. In the overall comparison, the eNOS G984T polymorphism was associated with an increased ED risk in allele contrast, dominant, heterozygote, and homozygote models (allele contrast: OR = 1.514, 95% confidence interval [CI]: 1.019–2.248). For 4 VNTR polymorphisms, the overall analysis showed a significant association between homozygote comparison and recessive genetic model (homozygote comparison: OR = 1.917, CI: 1.073–3.424). The eNOS T786C polymorphism increased ED risk in allele contrast, homozygote, and recessive models (allele contrast: OR = 1.588, CI: 1.316–1.915). Significant heterogeneity was mainly observed in studies on the G894T polymorphism. No publication bias was detected in all of the variants. Conclusion The eNOS polymorphisms G894T, 4 VNTR, and T786C were associated with an increased risk for ED. However, these results are still preliminary. Further studies based on different confounders and using a large population size should be conducted to generate more accurate and reliable conclusions.

Comprehensive insight into functional interaction between GNB3 C825T and eNOS T‐786C, G894T gene polymorphisms and association with susceptibility to diabetic erectile dysfunction

“…Moreover, the genotype distribution of the heterozygous GT genotype of G894T and of homozygote CC minor allele genotype of T‐786C suggests that these genotypes are associated with a high susceptibility to develop VED. Supporting our results, the heterozygote GT genotype was associated with an increased risk of ED in Asian populations (Liu et al ., ) and similar distribution of the eNOS T‐786C CC genotype with ED was reported in the Turkish population (Sinici et al ., ).…”

Aqueous extract of Lespedeza cuneata improves male menopause by increase of nitric oxide and dihydrotestosterone

“…The isoforms of NOS include inducible NOS (iNOS), endothelial NOS (eNOS), and neuronal NOS (nNOS) (Andersen et al, 2010;Masuda, 2008). Although iNOS is produced by specific cytokines as a part of the immune response by macrophages, eNOS and nNOS are essentially produced in endothelial cells and neurons (Dashwood et al, 2011;Fukuhara et al, 2011;Liu et al, 2015). Activation of NO is activated by increasing concentrations of calcium and calmodulin (Derar et al, 2017;Zheng et al, 2007).…”

Anatomic variation and orgasm: Could variations in anatomy explain differences in orgasmic success?

“…For men, it is clear that the balance between the sympathetic and parasympathetic systems is key to optimal erection and ejaculation (Zorba et al, ; Harte, ). Furthermore, studies focusing on sexual dysfunction, such as erectile dysfunction and premature ejaculation, highlight differences in anatomy that may cause these unfavorable differences in sexual experience (Lin et al, ; Liu et al, ). The debate on the importance of penis size in the sexual experience is controversial.…”

“…Examples of recent studies focus on erectile dysfunction and premature ejaculation. A recent meta‐analysis found a significant correlation between a few polymorphisms of nitric oxide synthase and an increased risk for erectile dysfunction (Liu et al, ). For patients with lifelong premature ejaculation, the sympathetic system was hyperactive, and the parasympathetic system was hypoactive (Zorba et al, ).…”