Reduction of Soluble Leptin Receptor Levels in Women with Unexplained Infertility and the Effect of Leptin Receptor Gln223Arg Polymorphism on its Serum Level

Background and Objectives: Soluble Leptin Receptor (sOB-R) is the most important leptin-binding protein that can affect the level of active biological leptin. The Gln223Arg polymorphism in the leptin receptor gene is associated with obesity, which can be a factor for infertility. The purpose of this study was to evaluate the sOB-R levels in women with unexplained infertility and to investigate the effect of leptin receptor (LEPR) gene polymorphism on sOB-R serum level. Methods: One hundred and two women with unexplained infertility and 112 fertile women were studied in this case-control study. The subjects in both groups had a normal hormonal profile with the age below 40 years. The sOB-R levels were measured using ELISA method. Results: There was a 2-fold decrease in sOB-R level in the infertile group compared to the control group (P=0.001). Although sOB-R levels were lower in overweight and obese infertile subjects, this difference was not significant. However, this difference was significant compared to the control group. There was a direct correlation between BMI, age, and infertility. Although sOB-R levels in Arg/Arg genotypes were higher in the infertile group than Gln/Gln and Arg/Gln genotypes, they were not statistically significant. A significant decrease was observed in sOB-R levels of Gln/Gln and Arg/Gln genotypes in the infertile group compared to the control. Conclusion: There was a reverse correlation between sOB-R levels and unexplained infertility. It seems that by a decrease in serum sOB-R, the serum leptin levels increase which can enhance leptin inhibitory effects in infertility.

کلیدواژه ها:

Gln223Arg polymorphism ، Leptin ، sOB-R levels ، Unexplained infertility