Effect of Body mass index on interleukin2, 6 and soluble fibroblast associated surface antigen in infertile men

Abstract

Background: obesity is an important cause of adverse health problems, including male infertility. Testosterone is essential for spermatogenesis and permits the release of mature sperms. In the absence of testosterone stimulation, spermatogenesis does not proceed beyond the meiosis stage. Aromatase expression is directly related to the degree of adiposity; it is dependent on cytokine stimulation and requires the presence of glucocorticoids, 17β-estradiol in the plasma of adult men is formed by aromatization convert testosterone and androstinedione to 17β-estradiol Apoptosis is an important process in the context of germ cells since they undergo both mitosis and meiosis, and this process is affected by interleukin 6and 2 (IL6 and IL2).
Objectives: To assess the effect of body mass index on serum sex steroidal hormones, seminal antiapoptotic factor soluble fibroblast associated surface antigen (sFas) and inflammatory markers (IL6, IL-2), with conventional semen parameters in infertile men.
Patients and methods: One hundred and six male partners of infertile couples were involved in the study. Height and weight of them were measured to calculate the body mass index (BMI). Serum testosterone and estradiol 2.were measured for all.Semen sample was taken after 2-7 days of abstinence. Conventional semen analysis was done for each sample according to the protocol of (WHO) 2010, after incubation and liquefaction period (30-60 min). Semen plasma was collected for analysis of interleukins (2 and 6) and sFAS .by specific kits Patients with severe oligospermia (below million sperm/ml) were excluded from the study. The rest (77) subjects were divided into three groups according to BMI (WHO, 2010) as follows: Normal (BMI < 25 kg/ m2) (n=24): Overweight (BMI ≥ 25 and < 30 kg/m2) (n=30): Obese (BMI > 30 kg/m2) (n=23).
Results: The results showed a significant decrease in Testosterone level and Testosterone/E2 ratio in overweigh and obese subjects as compared to normal. The results of conventional semen analysis showed significant difference in pH and no. of round cell between the two groups. There was positive correlation between IL2 with sFAS in the two groups, and negative correlation of IL2 with total progressive cell and motility in both overweigh and obese groups. There was positive correlation of IL6 with no. of round cells in both studied groups.
Conclusion: BMI affects Testosterone level and Testosterone/E2 ratio (they were significantly decreased in overweigh and obese patients). A positive correlation between IL2 and sFAS in obese patients as well as positive correlation of IL6 with round cells in obese patients indicate the role of apoptosis which is essential for normal fertility to remove abnormal and unwanted cells in ejaculate, in infertile overweight and obese patients.