Objective: To investigate the influence of inflammatory factors on semen parameters in the seminal plasma of obese men.
Methods: 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.
Results: 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).
Conclusions: 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.
目的： 探讨肥胖男性精浆中炎性因子对精液参数的影响。方法： 根据体质量指数（BMI）将171例研究对象分为正常组（BMI<24 kg/m2，n=59）、超重组（24≤BMI<28 kg/m2，n=54）和肥胖组（BMI=≥28 kg/m2，n=58）。采用CASA精液分析系统进行精液常规参数分析，ELISA法测定精浆中TNF-α、IL-6和VEGF水平，分析上述指标与BMI、精参数等的相关性。 结果： 正常组、超重组和肥胖组精子浓度分别为(66.54±34.81)、(57.73±24.61)、(40.19±24.05) ×10⁶/ml；精子总数分别为(200.75±102.66)、(157.46±112.89)、(110.22±75.44) ×106；前向运动精子百分率（PR%）分别为(50.75±10.17)%、(39.71±9.73)%、(30.80±15.56)%。肥胖组、超重组男性精液精子浓度、精子总数和PR%显著降低(P<0.01)。正常组、超重组和肥胖组TNF-α水平分别为(64.47±11.92)、(69.74±12.32)、(76.90±14.64) pg/ml，IL-6分别为（39.26±9.09）、(46.25±13.66)、(54.17±17.81) pg/ml， VEGF水平分别为(199.23±36.28)、(181.57±34.41)、(154.24±30.23) pg/ml；肥胖组、超重组精浆TNF-α、IL-6水平显著增高(P<0.05或P<0.01)，VEGF水平显著降低(P<0.01)。相关性分析显示，精浆TNF-α、IL-6和VEGF与BMI具有显著相关性（r=0.254、0.321、－0.407，P<0.01）；精浆TNF-α、IL-6与PR%具有负相关（r=－0.163、P<0.05，r=－0.333、P<0.01），精浆VEGF含量与精液量、精子浓度、精子总数和PR%均具有正相关（r=0.238、P<0.01，r=0.197、P<0.05，r=0.278、P<0.01，r=0.195、P<0.05）。TNF-α与IL-6显著正相关（r=0.468、P<0.01），IL-6与VEGF呈负相关（r=-0.177、P<0.05），TNF-α与VEGF之间无相关性（r=-0.058，P>0.05）。结论： 肥胖男性的精浆TNF-α、IL-6水平增高，VEGF水平降低，精浆中炎症因子的改变可能会影响精液质量。.
Keywords: body mass index; correlation analysis; interleukin; semen parameters; tumor necrosis factor-α; vascular endothelial growth factor; obesity.