Expression of oxidized low density lipoprotein receptor-1 in aorta of diabetic rat and intervention of rosiglitazone / 中华老年医学杂志

ABSTRACT

Objective To observe the protein and mRNA expression of LOX-1,eNOS and PPARγ in type 2 diabetic rat aorta,and to investigate the effect of rosiglitazone intervention.Methods Totally 80 Wistar rats (7-week-old male) were randomized into the control group,high fat diet group,diabetic group,and rosiglitazone treatment group (n=20 each).Type 2 diabetes model was developed by intraperitoneal injection with a low dose of streptozotocin,and rats in rosiglization treatment group were treated with rosiglitazone by intragastric administration.After treatment with rosiglitazone for 6 and 12 weeks,animals were sacrificed.Aorta were collected for detecting the protein and mRNA expressions of LOX-1,eNOS and PPARγ,and the differences in expression levels were compared among groups.Results After 6 and 12 weeks,the protein expressions of LOX-1 were up-regulated in diabetic group and rosiglitazone treatment group as compared with control group and high fat diet group (all P＜ 0.01).The protein expression of LOX-1 was down-regulated in rosiglitazone treatment group as compared with diabetic group (P ＜ 0.05).The aorta protein expressions of LOX-1 in high diet group,diabetes group and rosiglitazone treatment group were upregulated after 12 weeks as compared with 6 weeks (all P＜0.01).After 6 and 12 weeks,the aorta protein expressions of eNOS were down-regulated and PPARγ were up-regulated in high fat diet group,diabetic group and rosiglitazone treatment group as compared with control group (all P＜0.01)The aorta protein expression of eNOS was down-regulated and PPARγwas up-regulated in diabetes group as compared with high fat diet group and rosiglitazone treatment group (all P＜0.01).The aorta protein expressions of eNOS in diabetes group and rosiglitazone treatment group were downregulated after 12 weeks as compared with 6 weeks (all P＜0.01).After 6 and 12 weeks,the aorta mRNA expressions of LOX-1 and PPARγ were up-regulated,but the mRNA expressions of eNOS were down-regulated in high fat diet group,diabetes group and rosiglitazone treatment group as compared with control group (all P＜0.05).The aorta mRNA expressions of LOX-1 and PPARγ were up-regulated,but the mRNA expressions of eNOS were down-regulated in diabetes group and rosiglitazone treatment group as compared with high fat diet group (all P＜0.05).The aorta mRNA expressions of LOX-1 and PPARγ were down-regulated,but the mRNA expressions of eNOS were upregulated in rosiglitazone treatment group as compared to diabetic group (all P＜0.01).Conclusions Both hyperglycemia and hyper-lipoproteinemia can induce early coronary atherosclerosis in rats with the abnormal protein and mRNA expressions of LOX-1,eNOS and PPARγ in rat aorta,and the abnormal expressions are more obvious in hyperglycemia combined with hyperlipoproteinemia.Thiazolidinediones can reverse the above abnormal expressions in diabetic rats.