Study On Mechanism Of Total Glucosides Of Paeony’s Effect On Adriamycin Induced Nephropathy Based On PPARγ/ANGPTL4

Nephrotic syndrome (NS) is a common kidney disease. The main clinical features of Nephrotic Syndrome are proteinuria,hypoalbuminemia, hyperlipidemia and systemic edema. The Glomerular filtration barrier impaired cause NS directly. Podocyte and slit diaphragm which are the last layer of glomerular filtration barrier, play an important role in glomerular filtration function. ANGPTL4 is a newly discovered secreted protein. Overexpression ANGPTL4 secreted by podocyte can cause podocyte injury, thus induce massive proteinuria. ANGPTL4 is verified a target gene of peroxisome proliferater-activated receptor y(PPARy). Researches have showed that high expression of PPARy in Glomerular, can reduce podocyte injury. Total glucosides of paeony(TGP) is extracted from the dry root extract of Radix Paeoniae Alba. The main pharmacological effects of TGP are anti-inflammatory and immunomodulatory. Studies showed that TGP has a certain therapeutic effect on renal damage in nephrotic syndrome, and TGP can alleviate the proteinuria in the patients with renal disease. But it’s pharmacological effects and mechanisms need to be further clarified.Therefore,this paper established a NS model through one-time intravenous injection of doxorubicin to research TGP’s therapeutic effect of NS. And we cultured podocytes in vitro to observe the protective effect of TGP on podocytes which stimulated by Adriamycin. Thus further explore wheather TGP play the effect on NS through PPARy/ANGPTL4Methods:1, The effect of TGP on NS rats and on regulation of PPARy/ANGPTL4Fifty SD rats were used, ten rats were used as control, and the other forty rats were intravenous injected of adriamycin according to literature methods.Then the successful modeling animals were divided into model group, TGP high dose group(TGPH),TGP low dose group(TGPL) and tacrolimus group(FK506). The treatment groups were orally administered the drugs at the 2 week, and last for 6 weeks.②The general condition and 24h urinary protein were detected during the treatment were detected. And the levels of serum creatinine (SCr), urea nitrogen (BUN), triglycerides (TG), total cholesterol (TC), albumin (propagated), total protein (TP)were measured. Meanwhile, the morphological changes in the kidney were evaluated by HE staining. Also, Immunohistochemical staining with desmin and synopdin expression to measure the protective effect of TGP on podocyte injury.②The mRNA levels of PPARy and ANGPTL4 in kidneys were measured by RT-PCR, the protein expression levels of PPARy and ANGPTL4 in kidneys were determined by Western blot.2 The TGP play a protective effect on adriamycin induced podocyte injury by PPARγ/ ANGPTL4.We cultured immortalized mouse podocytes, and differentiated podocytes were treated with follows:control group:without any treat. Adriamycin group:podocytes were exposed to adriamycin(0.1μmoL/L,24h);TGP group:podocytes were treated with adriamycin (0.1μmoL/L,24h) and TGP(0.1g/mL,24h); GW9662 group:podocytes were treated with adriamycin (0.1μmoL/L,24h) and GW9662(1μmol/L,24h); GW9662+TGP group:podocytes were treated with TGP(0.1g/mL,24h),adriamycin(0.1μmoL/L,24h)and GW9662(1μmol/L,24h)①Cell viability was detected by MTT, and the apoptosis rate was measured by Annexin V/FITC apoptosis detection kit. The expression of desmin and synopodin were measured by immunofluorescence.②And the expression of PPARy and ANGPTL4 in podocyte were detected by Western blot.Results:1 The effect of TGP on NS rats and on regulation of PPARy/ANGPTL4①Compared with model group, better general condition, decreased 24h urinary protein were observed in TGPH group and TGPLgroup. Also, TGPH and TGPL group showed decreased levels of SCr, BUN, TG, and TC but increased levels of ALB, TP in serum when compared to model group. Meanwhile, TGP treatment could ameliorate the renal pathological lesion. Futhermore, TGP treatment could improve the expression of synopodin,and decreased the expression of desmin②The RT-PCR results showed that the mRNA level of PPARy was increased but the ANGPTL4 level was decreased in TGP treatment rats when compared to model group. Also,the protein level of PPARy was increased but the ANGPTL4 level was decreased in TGP treatment rats when compared to model group.2 The TGP play a protective effect on adriamycin induced podocyte injury by PPARγ/ ANGPTL4.①TGP play a protective effect on cultured podocytes in vitro.TGP treatment increased the cell viability and decreased the cell apoptosis rate. Also, TGP decreased the expression of desmin and increased the expression of synopodin.The GW9662 treatment reduced the cell viability and induced cell apoptosis,when compared to adriamycin group. Also, the desmin expression increased and the synopodin expression decreased in GW9662 group. Futhermore when PPARy was inhibited, TGP couldn’t improve the cell viability and decreased the cell apoptosis rate any more.Also, the exoression of desmin and synopodin in TGP+GW9662 group was the same with the GW9662group.②TGP treatment group showed increased expression of PPARy and decreased expression of ANGPTL4,when compared to adriamycin group. Comparing with adriamycin group, the GW9662 group showed decreased expression of PPARγ and raised.The TGP+GW9662 group showed the same expression of PPARy and ANGPTL4 with GW9662 group.Conclusions:1 TGP exhibited a therapeutic effect on NS rats through reducing contents of urine protein in 24h, attenuating pathologic changes, and protecting the podocytes from injurying. It may exhibit this effect by increasing the expression of PPARy and decreasing the ANGPTL4 exoression.2 TGP play a protective effect on cultured podocytes in vitro by increasing the cell viability decreasing the cell apoptosis rate,raising the synopodin level and decreasing the desmin level. The PPARy/ANGPTL4 play a regulatory role in the process of NS podcyte damage. And the effect of TGP may through raising the expression of PPARy and thus decreasing the ANGPTL4 expression.