[Correlation of semen parameters with inflammatory factors in the seminal plasma of obese males]

To investigate the influence of inflammatory factors on semen parameters in the seminal plasma of obese men.

Based on the body mass index (BMI), 171 males were divided into a normal group (BMI < 24 kg/m2, n = 59), an overweight group (24 ≤ BMI < 28 kg/m2, n = 54), and an obesity group (BMI =≥ 28 kg/m2, n = 58). The routine semen parameters of the subjects were obtained by computer-assisted semen analysis, the levels of TNF-α, IL-6 and VEGF in the seminal plasma were measured by ELISA, and the correlation of BMI with the above indexes was analyzed.

Sperm concentration was significantly decreased in the obesity group in comparison with the normal and overweight groups (［40.19 ± 24.05］ vs ［66.54 ± 34.81］ and ［57.73 ± 24.61］ ×10⁶/ml, P <0.01), and so was the total number of sperm (［110.22 ± 75.44］ vs ［200.75 ± 102.66］ and ［157.46 ± 112.89］ ×106, P <0.01) and the percentage of progressively motile sperm (PMS) (［30.80 ± 15.56］ vs ［50.75 ± 10.17］ and ［39.71 ± 9.73］%, P <0.01). The levels of TNF-α and IL-6 in the seminal plasma were markedly elevated in the obesity group as compared with the normal and overweight groups (［76.90 ± 14.64］ vs ［64.47 ± 11.92］ and ［69.74 ± 12.32］ pg/ml, P <0.05; ［54.17 ± 17.81］ vs ［39.26 ± 9.09］ and ［46.25 ± 13.66］ pg/ml, P <0.01), while that of VEGF remarkably reduced in the former group in comparison with the latter two (［154.24 ± 30.23］ vs ［199.23 ± 36.28］ and ［181.57 ± 34.41］ pg/ml, P <0.01). The levels of TNF-α, IL-6, and VEGF were significantly correlated with BMI (r = 0.254, 0.321 and －0.407, P <0.01), those of TNF-α and IL-6 negatively with the percentage of PMS (r =－0.163, P <0.05; r = －0.333, P <0.01). There was a positive correlation between TNF-α and IL-6 (r = 0.468, P <0.01), a negative correlation between IL-6 and VEGF (r = 0.177, P <0.05), but no correlation between TNF-α and VEGF (r = 0.058, P >0.05).

The levels of TNF-α and IL-6 are increased and that of VEGF decreased in the seminal plasma of obese males, which may affect the semen quality.