Objective: To investigate the influence of insulin resistance on male reproductive hormones and semen quality.
Methods: Using the electrochemiluminescence method, we measured the levels of follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), estradiol (E2) and testosterone (T) in the serum of 83 infertile males. We detected the levels of fasting plasma glucose (FPG) and fasting insulin (FINS) and calculated the insulin resistance index presented as homeostasis model assessment of insulin resistance (HOMA-IR). Based on HOMA-IR, we divided the patients into three tertile groups, T1 (HOMA-IR 0.36－0.55, n = 27), T2 (HOMA-IR 0.56－0.80, n = 28) and T3 (HOMA-IR 0.81－1.97, n = 28), obtained their semen parameters by computer-assisted semen analysis (CASA) and analyzed the correlation of HOMA-IR with male reproductive hormone levels and semen parameters.
Results: With the elevation of HOMA-IR, the patients of the T1, T2 and T3 groups showed significant decreases in the serum T level (［14,26 ± 4.27］ vs ［14.75 ± 5.00］ vs ［11.62 ± 3.68］ nmol/L, P <0.05) and the percentage of progressively motile sperm (PMS) (［51.04 ± 15.10］% vs ［48.04 ± 16.24］% vs ［37.84 ± 18.23］%, P <0.05). HOMA-IR was correlated negatively with the serum T level (r = －0.333, P = 0.002), semen volume (r = －0.23, P = 0.029) and PMS (r = －0.27, P = 0.015), and so was FINS with the serum T level (r = －0.327, P = 0.003) and PMS (r = －0.315, P = 0.004), while the semen volume was correlated positively with the levels of serum T (r = 0.221, P = 0.048) and FSH (r = 0.222, P = 0.047). Multivariate linear regression analysis showed that HOMA-IR was an independent influencing factor for PMS and the body mass index (BMI) was that for the semen volume and total sperm count.
Conclusions: Insulin resistance may reduce semen quality by changing the levels of male reproductive hormones.
目的： 探讨胰岛素抵抗对男性生殖激素和精液参数的影响。方法： 选择男性不育症患者83例作为研究对象。应用电化学发光法测定血清中卵泡刺激素（FSH）、黄体生成素（LH）、泌乳素（PRL）、雌二醇（E2）和睾酮（T）；测定所有受试者空腹血糖（FPG）及空腹胰岛素（FINS）。用稳态模型评价胰岛素抵抗，计算胰岛素抵抗指数（HOMA-IR），并根据HOMA-IR值(分别为0.36~0.55、0.56~0.80、0.81~1.97)将83例研究对象分为T1（n=27）、T2（n=28）和T3（n=28）3组。用计算机辅助精液分析系统(CASA)分析精液参数，分析HOMA-IR与男性生殖激素水平及精液参数的关系。结果： T1、T2、T3 3组间T分别为（14.26±4.27)、（14.75±5.00)、(11.62±3.68) nmol/L，前向运动精子百分率分别为（51.04±15.10)%、（48.04±16.24)%、 (37.84±18.23)%，T1、T2组与T3组比较，有显著性差异(P均<0.05)。相关性分析发现，FINS与血清T、前向运动精子百分率呈负相关（r=－0.327 ,P=0.003；r=－0.315 ,P=0.004）；HOMA-IR与血清T、精液量、前向运动精子百分率呈显著负相关（r=－0.333,P=0.002；r=－0.23,P=0.029；r=－0.27,P=0.015）?gt;毫坑胙錐SH、T呈正相关（r= 0.222,P=0.047；r=0.221,P=0.048）。多元线性回归分析发现，体质量指数（BMI）是精液量、精子总数的独立影响因素；HOMA-IR是前向运动精子百分率的独立影响因素。结论： 男性胰岛素抵抗可通过血清T改变，进而降低精液质量。.
Keywords: homeostasis model assessment of insulin resistance; insulin resistance; male infertility; reproductive hormones; semen parameters.