人参皂苷对波动性高血糖模型大鼠动脉HO-1、γ-GCS表达的影响

Ginsenoside on Arterial HO-1 and γ-GCS Expression in Rats with Fluctuating Hyperglycaemia

目的观察人参皂苷对波动性高血糖模型大鼠动脉血红素氧合酶-1(HO-1)、γ-谷氨酰半胱氨酸合成酶(γ-GCS)表达的影响。方法将48只雄性SD大鼠随机分成正常对照组(n=8)和糖尿病模型组(n=40)。高脂饲料喂养糖尿病模型组大鼠2周后用小剂量链脲佐菌素(STZ)诱导建立糖尿病大鼠模型,之后随机分为稳定性高糖组(n=8)和波动性高糖组(n=32),波动性高糖组错时注射葡萄糖、胰岛素制备血糖波动大鼠模型。2周后,将波动性高糖组大鼠随机分为人参皂苷低剂量组[14mg/(kg·d)]、人参皂苷中剂量组[28mg/(kg·d)]、人参皂苷高剂量组[56mg/(kg·d)]及波动性高糖空白组,每组8只,予人参皂苷低、中、高剂量干预相对应的模型组8周。实验结束后取大鼠动脉组织,采用Rt-PCR、Western blot测定HO-1、γ-GCS m RNA及蛋白表达。结果与正常对照组比较,糖尿病模型组HO-1、γ-GCS m RNA及蛋白表达明显增加(均P<0.05);与稳定性高糖组比较,波动性高糖空白组、人参皂苷给药组(低、中、高)HO-1、γ-GCS m RNA表达均明显增加[(19.66±1.20,15.53±0.87),(21.72±2.27,18.85±1.93),(23.82±0.50,21.65±2.17),(25.90±1.13,26.30±1.68)比(17.30±0.56,12.50±0.97),均P<0.05],蛋白表达量均明显增加[(64.78±0.25,67.21±0.68),(77.34±0.29,83.48±0.43),(82.65±0.29,94.39±0.22),(92.71±0.20,107.73±1.28)比(63.28±0.29,59.20±0.66),均P<0.05];与波动性高糖空白组比较,人参皂苷给药组(低、中、高)HO-1、γ-GCS m RNA表达均明显增加[(21.72±2.27,18.85±1.93),(23.82±0.50,21.65±2.17),(25.90±1.13,26.30±1.68)比(19.66±1.20,15.53±0.87,均P<0.05],蛋白表达量均明显增加[(77.34±0.29,83.48±0.43),(82.65±0.29,94.39±0.22),(92.71±0.20,107.73±1.28)比(64.78±0.25,67.21±0.68),均P<0.05];与人参皂苷低剂量组比较,人参皂苷中、高剂量组HO-1、γ-GCS m RNA表达明显增加[(23.82±0.50,21.65±2.17),(25.90±1.13,26.30±1.68)比(21.72±2.27,18.85±1.93),均P<0.05],蛋白表达量明显增加[(82.65±0.29,94.39±0.22),(92.71±0.20,107.73±1.28)比(77.34±0.29,83.48±0.43),P<0.05];与人参皂苷中剂量组比较,人参皂苷高剂量组HO-1、γ-GCS m RNA表达明显增加[(25.90±1.13,26.30±1.68)比(23.82±0.50,21.65±2.17),均P<0.05],蛋白表达明显增加[(92.71±0.20,107.73±1.28)比(82.65±0.29,94.39±0.22),均P<0.05]。结论人参皂苷可增加波动性高血糖模型大鼠HO-1、γ-GCS m RNA及蛋白表达水平,减轻血管内皮损伤,可能降低波动性高血糖大鼠机体的氧化应激水平,提高抗氧化能力,对波动性高血糖所导致的动脉病变有一定保护作用。

Objective To investigate the effects of ginsenoside on arterial hemeoxygenase-1 （HO-1） and γ-glu-tamylcysteine synthetase （γ-GCS） expression of rats with fluctuating hyperglycaemia. Methods Forty-eight male Sprague-Dawley （SD） rats were randomly divided into healthy group （n=8） and diabetic model group （n=40）. The diabetic rat model was established by injection of a small dose of streptozotoein after feeding them with high-fat diet for 2 weeks, then they were randomly divided into sustained high glucose group （n=8） and fluctuating high glucose group （n=32）. The model rats with high glucose fluctuation were developed by alternative intraperitoneal injection of insulin and glucose, then after 2 weeks were randomly divided into 4 groups： low [14mg/（kg·d）], mid-dle [28mg/（kg·d）], high [56mg/（kg·d）] dosage of ginsenoside treatment group and control group, with 8 rats in each group. After 8 weeks, the expression of HO-1 and γ-GCS mRNA and protein were measured and compared. Results Compared with healthy group, the levels of HO-1 and γ-GCS in diabetic model group were significantly increased （P〈0.05）; compared with sustained high glucose group, the levels of HO-1 and γ-GCS mRNA in fluc-tuating high glucose group and ginsenoside treatment groups （low, middle, high） were significantly increased [（19.66±1.20, 15.53±0.87）, （21.72±2.27, 18.85±1.93）, （23.82±0.50, 21.65±2.17）, （25.90±1.13, 26.30±1.68）vs （17.30±0.56, 12.50±0.97）; all P〈0.05];the same increase was observed in protein levels [（64.78±0.25, 67.21±0.68）, （77.34±0.29, 83.48±0.43）, （82.65±0.29, 94.39±0.22）, （92.71±0.20, 107.73±1.28） vs （63.28±0.29, 59.20±0.66）; all P〈0.05]. Compared with fluctuating high glucose group, the levels of HO-1 and γ-GCS mRNA in ginsenoside treatment groups （low, middle, high） were significantly increased [（21.72±2.27, 18.85±1.93）, （23.82±0.50, 21.65± 2.17）, （25.90 ±1.13, 26.30 ±1.68）vs （19.66 ±1.20, 15.53 ±0.87）; all P〈0.05], as well as the expression of protein [（77.34±0.29, 83.48±0.43）, （82.65±0.29, 94.39±0.22）, （92.71±0.20, 107.73±1.28）vs（64.78±0.2, 67.21±0.68）; all P〈0.05]. Compared with low-dose ginsenoside group, middle-dose and high-dose ginsenoside groups had higher levels of HO-1 and γ-GCS mRNA [（23.82±0.50, 21.65±2.17）, （25.90±1.13, 26.30±1.68）vs（21.72±2.27, 18.85±1.93）; all P〈0.05] and protein [（82.65±0.29, 94.39±0.22）, （92.71±0.20, 107.73±1.28）vs（77.34±0.29, 83.48±0.43）; all P〈0.05]. Compared with middle-dose ginsenoside group, high-dose ginsenoside group had increased levels of HO-1 and γ-GCS mRNA [（25.90±1.13, 26.30±1.68）vs （23.82±0.50, 21.65±2.17）; P〈0.05] and protein [（92.71±0.20, 107.73± 1.28） vs （82.65±0.29, 94.39±0.22）; P〈0.05]. Conclusion Ginsenoside can increase the level of HO-1 and γ-GCS both in mRNA and protein and reduce vascular endothelial damage. Therefore ginsenoside may reduce the ox-idative stress level of rats wiht high blood-glucose fluctuation, improve the antioxidant capacity, which could play a critical role in treating vascular disease caused by high blood-glucose fluctuation.