The Therapeutic Effect Of Polygonatum Sibiricum Polysaccharid On DN Rats And The Possible Mechanism

OBJECTIVE:To observe the therapeutic effect of Polygonatum Sibiricum Polysaccharid(PSP)on diabetic nephropathy(DN) rats, and to explore its effect on the Angiotensinâ…¡(Angll)'s and Malondialdehyde(MDA)'s level of rats'renal cortex.METHODS:58 healthy male SD rats were enrolled, while 10 were set as blank control group and the left were established as type 1 diabetes model with Streptozotocin (STZ) intraperitoneal injection, and average into DM model control group, captopril group, high dose PSP group and low dose PSP group, The rats which were established model successfully, were given corresponding drug intragastrically for four weeks, then the body weight, kidney weight,24h microalbunminuria(UMA), serum creatinine(SCR), blood urea nitrogen(BUN), Angll and MDA of the renal cortex were tested.RESULT:Contrast with blank control group, except for the significant decrease of body weight (p<0.01 or p<0.05), all the other indexes of DM model rats were increased significantly(p<0.01 or p<0.05). Compared with model control group, the rats of captopril group, high dose and low dose PSP group had a obviously heavier body weight(p<0.01) and 24h UMA, SCR, BUN, Angll and MDA of the renal cortex were decreasd significantly(p<0.01 or p<0.05),while the blood sugar level was reduced in PSP group alone(p<0.01). On the other hand, the SCR, BUN and Angll level of both dosage PSP groups were obviously higher than captopril group, and the body weight, ratio of kidney to body weight,24h UMA and MDA of the renal cortex didn't display any significant difference among captopril group, low dose PSP group and high dose PSP group.CONCLUSION:The PSP has a considerable effect of decreasing the blood sugar level of DM rat, while compared with catopril, PSP has a similar positive effect on 24h UMA, body weight, ratio of kidney to body weight and MDA of the renal cortex, but weaker effect on reducing the SCR, BUN and Angll of the renal cortex. The detailed mechanism maybe relevant with the antioxidative effect, RAS activity inhibition and down regulation of AGEs induced tissue impairment caused by PSP.