红芪多糖对糖尿病心肌病db/db小鼠心肌损伤的改善作用

Improvement of Hedysarum Polybotrys Polysacchcaideon on myocardial damage of db/db mice with diabetic cardiomyopathy

目的研究红芪多糖(HPS)对糖尿病心肌病(DC)db/db小鼠心肌组织中过氧化物酶体增值物激活受体γ(PPAR-γ)及葡萄糖转运蛋白4(GLu T4)在心肌组织表达的影响。方法根据体重大小将6周龄的雄性db/db小鼠随机分为5组:模型组(0.9%Na Cl 0.2 m L·d^(-1))、对照组(罗格列酮,4 mg·kg^(-1)·d^(-1))、大中小3个剂量(HPS 200,100,50 mg·kg^(-1)·d^(-1))实验组;正常组(0.9%Na Cl0.2 m L·d^(-1))为同周龄同背景非转基因db/m小鼠12只。连续灌胃8周。于给药前及给药后第2,4,6,8周末,检测小鼠血糖浓度;第8周末处死小鼠,心脏取血并分离血清。用生化法检测血脂及心肌组织中超氧化物歧化酶(SOD)与还原型谷胱甘肽(GSH-PX)活性及丙二醛(MDA)含量;用反转录聚合酶链式反应、蛋白质印迹法检测心肌组织PPAR-γ及Glu T-4 mRNA和蛋白的表达。结果给药8周后,与模型组的血糖为(23.17±2.55)mmol·L^(-1)、三酰甘油(TG)为(5.78±0.50)mmol·L^(-1)、总胆固醇(TC)为(5.93±0.60)mmol·L^(-1)比较,高、中2个剂量实验组和对照组的血糖分别为(16.49±3.64),(17.80±4.40),(16.76±3.25),mmol·L^(-1);这3组的TG分别为(1.59±0.43),(4.02±0.54),(1.12±0.32)mmol·L^(-1);这3组的TC分别为(2.77±0.40),(4.65±0.58),(4.85±0.48)mmol·L^(-1),差异均有统计学意义(P<0.05或P<0.01)。与模型组的SOD为(140.70±1.04)mg·m L^(-1)、GSH-PX为(110.91±0.82)U·mg^(-1)、MDA为(7.20±0.49)nmol·mg^(-1)比较,这3组的SOD分别为(145.81±0.99),(142.21±1.09),(145.70±1.10)mg·m L^(-1),活性显著增强;这3组的GSH-PX分别为(114.94±0.78),(112.10±0.86),(114.84±0.86)U·mg^(-1),活性显著增强;这3组的MDA分别为(5.82±0.52),(6.62±0.67),(5.80±0.52)nmol·mg^(-1),含量显著下降,差异均有统计学意义(P<0.05或P<0.01)。与模型组的PPAR-γmRNA和PPAR-γ蛋白表达分别为0.34±0.11,0.75±0.12、GLu T4 mRNA和GLu T4蛋白表达分别为0.26±0.01,0.42±0.02比较,3个剂量实验组和对照组的PPAR-γmRNA和PPAR-γ蛋白表达分别为0.76±0.06,0.56±0.08,0.45±0.08,0.79±0.10;1.78±0.08,1.44±0.07,1.07±0.05,1.63±0.02。这4组的GLu T4 mRNA和GLu T4蛋白表达分别为0.68±0.05,0.48±0.03,0.49±0.03,0.93±0.05;0.61±0.01,0.45±0.02,0.42±0.01,0.59±0.01,差异均有统计学意义(P<0.01),尤以高剂量组为显著。结论 HPS可降低db/db小鼠的血糖、血脂,同时上调PPAR-γ及Glu T-4的表达,从而改善模型鼠糖、脂代谢紊乱,减缓糖尿病心肌病的病程进展。

Objective To observe the effect of Hedysarum Polybotrys Polysacchcaide（ HPS） on the expression of peroxisome proliferator-activated receptor-γ（ PPAR-γ） and glucose transporter-4（ GLu T4） in myocardial tissue in diabetes（ db/db） mice with diabetic cardiomyopathy. Methods The male db/db mice of 6-weeks age were randomly divided into 5 groups on the basis of weight： model group（ 0. 9% Na Cl by gavage）,control group（ 4 mg·kg^（-1）·d-1rosiglitazone） and high,middle and low doses（ 200,100,and 50 mg·kg^（-1）·d-1HPS） experimental groups. The same age were included in the normal group. Continuously administrating for 8 weeks. The blood glucose of mice was tested before and after administration of 2,4,6,8 weeks later. The activity of blood lipid,superoxide dismutase（ SOD）,glutathione peroxidase（ GSH-PX） and the content of malondialdehyde（ MDA） were detected by biochemical method after 8 weeks. Reverse transcription polymerase chain reaction method and Western blotting method were used to detect the expression of PPARγ,Glu T4 mRNA and protein in myocardial tissue. Results After the treatment of HPS for 8weeks,compared to the model group on the blood glucose（ BG） was（ 23. 17 ± 2. 55） mmol·L-1,on the triglyceride（ TG） was（ 5. 78 ± 0. 50） mmol·L-1and on the total cholesterol（ TC） was（ 5. 93 ± 0. 60） mmol·L-1; the BG in high and middle doses experimental groups and control group were（ 16. 49 ± 3. 64）,（ 17. 80 ± 4. 40）,（ 16. 76 ± 3. 25）,mmol·L-1,the TG in above groups were（ 1. 59 ± 0. 43）,（ 4. 02 ± 0. 54）,（ 1. 12 ± 0. 32） mmol·L-1; the TC in above groups were（ 2. 77 ± 0. 40）,（ 4. 65 ± 0. 58）,（ 4. 85 ± 0. 48） mmol · L-1with statistical difference（ all P〈0. 01）.Compared to the model group on the SOD was（ 140. 70 ± 1. 04） mg·m L-1,on the GSH-PX was（ 110. 91 ± 0. 82）U·mg-1,on the MDA was（ 145. 70 ± 1. 10） mg·m L-1,the SOD in three doses experimental groups and control group were（ 145. 81 ± 0. 99）,（ 142. 21 ± 1. 09）,（ 145. 70 ± 1. 10） mg·m L-1respectively,and the GSH-PX in that three doses groups were（ 114. 94 ± 0. 78）,（ 112. 10 ± 0. 86）,（ 114. 84 ± 0. 86） U · mg-1,and the MDA were（ 5. 82 ± 0. 52）,（ 6. 62 ± 0. 67）,（ 5. 80 ± 0. 52） nmol·mg-1with statistical difference（ all P〈0. 05 or P〈0. 01）.Compared to the model group on the mRNA and protein of PPAR-γ were 0. 34 ± 0. 11,0. 75 ± 0. 12; on the mRNA and protein of Glu T-4 in model group were 0. 26 ± 0. 01,0. 42 ± 0. 02,but the expression of mRNA and protein of PPAR-γ in high,middle and low doses experimental groups and control group were 0. 76 ± 0. 06,0. 56 ± 0. 08,0. 45 ± 0. 08,0. 79 ± 0. 10; 1. 78 ± 0. 08,1. 44 ± 0. 07,1. 07 ± 0. 05,1. 63 ± 0. 02 with increased significantly（ all P〈0. 01）. The expression of mRNA and protein of Glu T-4 in the four groups were 0. 68 ± 0. 05,0. 48 ± 0. 03,0. 49 ± 0. 03,0. 93 ± 0. 05; 0. 61 ± 0. 01,0. 45 ± 0. 02,0. 42 ± 0. 01,0. 59 ± 0. 01 with increased significantly also（ all P〈0. 01）,especially in the high dose of HPS. Conclusion HPS might improve the blood glucose and blood lipid metabolism disorders of diabetic db/db mice. HPS reducing the blood glucose and blood lipids and raising the expression of PPAR-γ and Glu T-4. HPS slow down the progress of diabetic cardiomyopathy.