西红花酸对糖尿病大鼠体内晚期糖基化终产物的形成及其受体表达的影响

Effects of crocetin on formation of advanced glycation end products and expression of releptor for advanced glycation and prodmts protein in diabetic rats

目的:观察西红花酸对糖尿病(diabetic melli-tus,DM)大鼠晚期糖基化终产物(AGEs)的形成和受体(RAGE)蛋白表达的影响。方法:以链脲佐菌素诱导DM大鼠模型,并将DM大鼠随机分为DM模型组和西红花酸治疗组(50 mg.kg-1.d-1),另设正常组,给药21 d后,血糖仪测定大鼠空腹血糖;试剂盒分别测定AGEs中间产物即血清果糖胺(FMN)和糖化血红蛋白(GHb)的含量;荧光分光光度法测定主动脉及肠系膜血管床AGEs的水平;病理切片观察肠系膜动脉的变化;免疫组化法检测RAGE蛋白在肠系膜动脉中的表达。结果:西红花酸治疗后,对DM大鼠血糖值无明显影响;但FMN和GHb水平与模型组比明显下降;AGEs在主动脉和肠系膜血管床中沉积减少;肠系膜动脉血管损伤减轻;RAGE蛋白表达显著下降。结论:西红花酸可抑制蛋白质非酶糖化反应,减少AGEs及其中间产物的形成,下调RAGE蛋白表达,保护DM大鼠血管。

AIM： To study the effect of crocetin on the formation of advanced glycation end products （AGEs） and receptor for AGEs （RAGE） protein expression in diabetic rats induced by streptozotocin （STZ）. METHODS： Rats were injected STZ in tail vessel with a dose of 45 mg·kg^-1. 3 d later, the rats whose blood glucose were over 11.1 mmol·L^-1 were regarded as diabetic rats, and were divided randomly into two groups： diabetic mellitus （DM） group, eroeetin （50 mg·kg^-1, po） group. At the same time, 8 normal rats were regarded as control group. After 21 d treatment, The levels of fasting blood glucose （FBG）, serum fmetosamine （FMN） and glycosylated hemoglobin （GHb） were measured. The contents of AGEs in aorta and mesenterie vessel were detected by fluorospectrophotometry. HE staining for mesenterie aorta was performed, and RAGE protein expression was studies with immunohistochemical method. RESULTS： Compared with DM group, crocetin＇ did not decrease the level of FBG. However, it could decrease the levels of FMN and GHb in blood and AGEs in aorta and mesenteric vessel （P 〈 0.01 or 0.05）. HE staining demonstrated injure of mesenteric aorta attenuated and RAGE protein expression decreased after crocetin treatment. CONCLUSION： These results suggest that crocetin not only inhibit nonenzymatic glycation reaction but also reduce RAGE protein expression in diabetic rats, which may contribute to attenuate diabetic vascular complications.