银杏叶提取物对2型糖尿病大鼠睾丸间质细胞雄激素合成的影响

目的:研究银杏叶提取物(EGB)对2型糖尿病大鼠睾丸间质细胞雄激素合成的影响。方法:雄性SD大鼠30只,随机均分成3组:正常对照组、2型糖尿病组、EGB治疗组。用光镜和透射电镜观察EGB对2型糖尿病大鼠睾丸的形态学改变;ELISA法检测血清LH、T水平;半定量RT-PCR检测睾丸间质细胞类固醇激素合成急性调节蛋白(StAR)、细胞色素P450侧链裂解酶(P450scc)、细胞色素P45017a-羟化酶(P450c17)、3β-羟基类固醇脱氢酶Ⅰ型(3β-HSD1)、17β-羟基类固醇脱氢酶Ⅲ型(17β-HSD3)的mRNA水平。结果:糖尿病组光镜下睾丸间质细胞较正常对照组缩小;透射电镜下见到间质细胞核固缩,胞质内内质网减少。糖尿病组血清LH及T水平显著低于正常对照组(P<0.05);睾丸组织P450scc的mRNA水平显著低于正常对照组(P<0.01),StAR、17β-HSD3及3β-HSD1的mRNA水平也明显低于正常对照组(P<0.05),P450c17基因表达呈下降趋势(P>0.05);EGB治疗12周与糖尿病组比较睾丸组织病理改变较轻,血清LH、T含量升高(P<0.05),StAR、P450scc的mRNA水平升高(P<0.05),P450c17、17β-HSD3及3β-HSD1的mRNA水平呈上升趋势(P>0.05)。结论:EGB能减轻糖尿病大鼠睾丸损害并使2型糖尿病大鼠睾丸间质细胞合成和分泌T能力增强。

Ginkgo Biloba Extract Enhances Testosterone Synthesis of Leydig Cells in Type 2 Diabetic Rats

OBJECTIVE: To investigate the effects of Ginkgo biloba extract (EGB) on the testosterone synthesis in the Leydig cells of type 2 diabetic rats. METHODS: Thirty male SD rats were equally randomised into a normal control, a type 2 diabetic and an EGB group. Morphological changes of Leydig cells were observed by light microscopy (LM) and transmission electron microscopy (TEM), concentrations of serum luteinizing hormone (LH) and testosterone (T) were determined by enzyme linked immunosorbent assay (ELISA), and the mRNA levels in the steroidogenic acute regulatory protein (StAR), cytochrome P450 side chain cleavage (P450scc), cytochrome P450 17a-hydroxylase (P450c17), 17beta-hydroxysteroid dehydogenase 3 (17beta-HSD3) and 3beta-hydroxysteroid dehydogenasel (3beta-HSD1) from the Leydig cells were examined by RT-PCR. RESULTS: Compared with the normal control, there was a significant decrease in the number and volume of Leydig cells, the levels of serum LH and T and the expression of mRNA in StAR, P450scc, 17beta-HSD3 and 3beta-HSD1 in the type 2 diabetes group. And the expression of the P450c17 gene showed a tendency of descending, but with no significance. Compared with the type 2 diabetes group, 12 weeks of EGB treatment caused very slight pathological changes in the Leydig cells, significantly increased the concentrations of blood LH and T, markedly elevated the levels of mRNA in StAR and P450scc and induced an ascending tendency of the expressions of P450c17, 17beta-HSD3 and 3beta-HSD1. CONCLUSION: EGB enhances testosterone synthesis and secretion of Leydig cells by reducing the impairment of the testis in type 2 diabetic rats.