Wang Lei, Guo Zhixin, Wu Jieping, Yan Xuhong, Jing Xiaorui, Liu Jia
Department of Endocrinology, Second Hospital, Shanxi Medical University, Taiyuan 030001, China.
Department of Endocrinology, Second Hospital, Shanxi Medical University, Taiyuan 030001, China; Email:
Zhonghua Yi Xue Za Zhi. 2015 Jun 9;95(22):1773-8.
To explore the effects of telmisartan on the expressions of adiponectin and adiponectin receptor and its signal transduction pathway AMP-activated protein kinase (AMPK), Akt/endothelial nitric oxide synthase (Akt/e-NOS/NO) and examine the possible protective mechanisms of telmisartan in testis of type 1 diabetic rats.
A total of 27 male Sprague-Dawley rats were randomly divided into normal control (NC, n=8) group and diabetic model (n=19) group. Diabetes was induced by an intraperitoneal injection of streptozotocin (STZ). And 16 established diabetic rats were randomly divided into diabetic control (DM, n=8) and diabetic treated with telmisartan (DT, n=8) groups. Group DT received a lavage of telmisartan while groups NC and DM had an equal volume of normal saline by gavage. At the end of 8-week of telmisartan treatment, the animals were sacrificed after harvesting of blood samples. Bilateral testes were extracted and epididymis was minced for preparing sperm suspension. Blood samples were used to detect the related parameters. Some tresticular tissues were fixed in neutral 40% formaldehyde solution and processed for histological analysis. And the remaining testicular tissues were immediately placed into liquid nitrogen and then stored in a -70 °C refrigerator until analyses. The levels of insulin and sex hormone were detected by radioimmunoassay. The levels of adiponectin, interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) were assayed by enzyme-linked immunosorbent assay (ELISA). The mRNA expression of testicular adiponectin and its receptor was assessed by real-time fluorescent quantitative polymerase chain reaction (PCR). The protein expressions of testicular adiponectin, adiponectin receptor, AMPK, P-AMPK, AKT, P-AKT and e-NOS were analyzed by Western blot.
There was significant pathological changes in testes in group DM than that in group NC. The levels of P-AKT/AKT, e-NOS and NO were significantly increased in group DM than those in group NC [(1.54 ± 0.27) vs (1.00 ± 0.00), (1.56 ± 0.26) vs (1.00 ± 0.00), (1.75 ± 0.28) vs (1.08 ± 0.02) µmol/g, all P<0.05]. The levels of serum adiponectin,testicular adiponectin and its receptor 1, and the ratio of P-AMPK to AMPK significantly decreased in group DM than that in group NC [(622.46 ± 95.86) vs (2 022.07 ± 51.13)ng/ml, (0.66 ± 0.09) vs (1.00 ± 0.00), (0.68 ± 0.05) vs (1.00 ± 0.00), (0.34 ± 0.11) vs (1.00 ± 0.00), all P<0.05]. There was no significant difference in the expression of adiponectin receptor 2 between group DM and NC [(1.02 ± 0.13) vs (1.00 ± 0.00), P>0.05]. After 8-week telmisartan treatment, the pathological changes of testes became alleviated in diabetic rats. The levels of P-AKT/AKT, e-NOS and NO significantly decreased in group DT than those in group DM [(1.24 ± 0.39) vs (1.54 ± 0.27), (1.16 ± 0.47) vs (1.56 ± 0.26), (1.35 ± 0.30) vs (1.75 ± 0.28) µmol/g, all P<0.05]. The serum and testicular levels of adiponectin and testicular adiponectin receptor 1 significantly increased in group DT than those in group DM [(1 051.55 ± 102.55) vs (622.46 ± 95.86), (0.84 ± 0.09) vs (0.66 ± 0.09), (0.80 ± 0.07) vs (0.68 ± 0.05), all P<0.05]. No significant difference existed in the ratio of P-AMPK to AMPK in testes or the expression of adiponectin receptor 2 between group DM and NC [(0.65 ± 0.52) vs (0.34 ± 0.11), (1.02 ± 0.15) vs (1.02 ± 0.13), all P>0.05].
Telmisartan may reduce the injury degree of testes and play protective roles in testicular tissues in diabetic rats by regulating the expressions of adiponectin, adiponectin receptor and the signal pathways mediated by adiponectin receptor.
探讨替米沙坦对脂联素及其受体表达以及脂联素受体介导的信号转导通路AMP激活的蛋白激酶（AMPK）、Akt/内皮型一氧化氮合酶（Akt/e-NOS/NO）的影响，研究替米沙坦对1型糖尿病大鼠睾丸的可能保护机制。
将27只雄性Sprague-Dawley大鼠随机分为正常对照组（NC，n = 8）和糖尿病模型组（n = 19）。通过腹腔注射链脲佐菌素（STZ）诱导糖尿病。将16只已建立糖尿病模型的大鼠随机分为糖尿病对照组（DM，n = 8）和替米沙坦治疗糖尿病组（DT，n = 8）。DT组给予替米沙坦灌胃，NC组和DM组给予等体积生理盐水灌胃。替米沙坦治疗8周结束后，采集血样后处死动物。取出双侧睾丸，将附睾切碎制备精子悬液。血样用于检测相关参数。部分睾丸组织用40%中性甲醛固定，进行组织学分析。其余睾丸组织立即放入液氮中，然后储存在-70℃冰箱中直至分析。采用放射免疫法检测胰岛素和性激素水平。采用酶联免疫吸附测定法（ELISA）检测脂联素、白细胞介素-6（IL-6）和肿瘤坏死因子-α（TNF-α）水平。采用实时荧光定量聚合酶链反应（PCR）评估睾丸脂联素及其受体的mRNA表达。采用蛋白质免疫印迹法分析睾丸脂联素、脂联素受体、AMPK、磷酸化AMPK（P-AMPK）、AKT、磷酸化AKT（P-AKT）和e-NOS的蛋白表达。
DM组睾丸病理改变较NC组明显。DM组P-AKT/AKT、e-NOS和NO水平显著高于NC组[（1.54±0.27）比（1.00±0.00），（1.56±0.26）比（1.00±0.00），（1.75±0.28）比（1.08±0.02）μmol/g，均P<0.05]。DM组血清脂联素、睾丸脂联素及其受体1水平以及P-AMPK与AMPK的比值显著低于NC组[（622.46±95.86）比（2022.07±51.13）ng/ml，（0.66±0.09）比（1.00±0.00），（0.68±0.05）比（1.00±0.00），（0.34±0.11）比（1.00±0.00），均P<0.05]。DM组与NC组脂联素受体2的表达差异无统计学意义[（1.02±0.13）比（1.00±0.00），P>0.05]。替米沙坦治疗8周后，糖尿病大鼠睾丸病理改变减轻。DT组P-AKT/AKT、e-NOS和NO水平显著低于DM组[（1.24±（0.39）比（1.54±0.27），（1.16±0.47）比（1.56±0.26），（1.35±0.30）比（1.75±0.28）μmol/g，均P<0.05]。DT组血清和睾丸脂联素水平以及睾丸脂联素受体1显著高于DM组[（1051.55±102.55）比（622.46±95.86），（0.84±0.09）比（0.66±0.09），（0.80±0.07）比（0.68±0.05），均P<0.05]。DM组与DT组睾丸中P-AMPK与AMPK的比值以及脂联素受体2的表达差异无统计学意义[（0.65±0.52）比（0.34±0.11），（1.02±0.15）比（1.02±0.13），均P>0.05]。
替米沙坦可能通过调节脂联素、脂联素受体表达及脂联素受体介导的信号通路减轻糖尿病大鼠睾丸损伤程度，对睾丸组织起保护作用。
