Effects Of Erigeronbreviscapus On Receptor For Advanced Glycation End Products (RAGE) MRNA In Renal Tissue Of Diabetic Rats

OBJECTIVE AND BACKGROUND:As the modern life styland the prevalence of diabetes mellitus(DM) is increasing every year.Diabetic complication involves many organs,such as kidney,liver,cardiocascular,retina and so on.Diabetic nephropathy (DN) is a major microvascular complication in long-standing diabetic patients who eventually undergo renal dialysis or transplantation and is one of the most common cause of end-stage renal disease in the world,It cause disability,shorten life expectancy, and reduce quality of life.The pathogenesis of diabetic nephropathy is still unclear. Studies have revealed that.Advanced glycation and oxidative stress have been implicated in the development of diabetic nephropathy.Advanced glycation end products(AGEs) inducing renal hypertrophy and glomerulosclerosis by accumulating in renal cortex,mesangial region,glomerular basement membrane and lesion vessels. AGEs-RAGE interaction activates the second signal system,produces lots of cytokines, does impairment to renal glomerulus and tubule irreversibly.Therefore,limiting RAGE expression might be an intriguing concept to modulate DN in diabetic patients. Erigeronbreviscapus,is a plant-medicines derived from Erigeron breviscapus.Recent studies have revealed that erigeronbreviscapus can reduce the excretory rate of urinary albumin and is beneficial to diabetic patients who have earlier nephropathy.It has also revealed that erigeronbreviscapus can inhibit NF-κB,TGF-β,thus postponing the development of diabetic nephropathy.The aim of the present study was to determine whether erigeronbreviscapus affects expression of RAGE mRNA in renal cortex of streptozotocin-induced diabetic rats.RESERCH DESIGN AND METHODS:We induced Diabetic rats by an intraperitoneal injection of streptozotocin(STZ) in SD rats.The criterion of diagnosis of diabetes was the consecutive blood glucose level≥16.7 mmol/L.27 male SD rats were randomly divided into 3 groups,Diabetes adding erigeronbreviscapus group(DD group,intragastric administration erigeronbreviscapus 20mg/kg.d) and Diabetes group (D group) and normal control group(C group).The body weight and blood glucose were measured every two weeks.8 weeks later,all rats were killed and the expression of RAGE was semiquantified in renal cortex by reverse transcription-polymerase chain reaction(RT-PCR),and renal morphology was evaluated respectively.RESULTS:1.The RAGE expression was increased in renal cortex of diabetic rats. RAGE/β-actin ratio of diabetic group was significantly higher than that of the control (P＜0.01).2.After treatment with erigeronbreviscapus,RAGE expression decreased significantly.CONCLUSIONS:1.The high expression of RAGE may participate in the renal damage of diabetic rats.2.Erigeronbreviscapus have no effect on the level of serum glucose,but significantly down-regulate RAGE expression in renal.It may have some renal protective effect on diabetic,nephropathy,partly through inhibition of excessive expression of RAGE in renal cortex.