Protective Effect of Salvia Przewalskii Extract on Puromycin-Induced Podocyte Injury.

BACKGROUND: To determine the effect of Salvia przewalskii extract (SPE) from total phenolic acids on puromycin aminonucleoside (PAN)-induced rat podocyte injury. METHODS: The rats were divided into groups that were treated with either PAN only or PAN followed by tacrolimus or SPE. We evaluated the effects of SPE on podocyte injury 5, 10, 15 and 21 days following treatment. RESULTS: (1) Proteinuria was observed starting on day 5 in all groups. The peak levels of proteinuria differed among the groups with tacrolimus and high-dose SPE, which significantly decreased proteinuria relative to the PAN and low- and medium-dose SPE groups. The proteinuria in each group decreased by day 15 and returned to a normal level by day 21. (2) H&E and PAS staining revealed no abnormality in glomerular morphology. With electron microscopy, we observed foot process effacement in the rats of all groups starting on day 5, but rats in the tacrolimus and high-dose SPE groups exhibited a lower degree. (3) IHC staining of nephrin and podocin revealed unaffected expression and better linear distributions in the high-dose SPE and tacrolimus groups. Western blot analysis confirmed that SPE could improve the expression of proteins. (4) The mRNA levels of nephrin and podocin in the tacrolimus and high-dose SPE groups were significantly higher than that in the others. CONCLUSION: In our study, we first demonstrated the ability of SPE to reduce proteinuria, preserve the morphology and structure of podocytes and retain the levels of slit diaphragm proteins on PAN-induced rat podocytes injury.

Transplantation of endothelial progenitor cells alleviates renal interstitial fibrosis in a mouse model of unilateral ureteral obstruction.

AIMS: The present study investigated whether transplantation of bone marrow-derived endothelial progenitor cells (BM-EPCs) in renal capillary network improves renal interstitial fibrosis in unilateral ureteral obstruction (UUO) model in mice. MAIN METHODS: Ex vivo generated, characterized, and cultivated mice BM-EPCs were identified by their vasculogenic properties in vitro. BM-EPCs were labelled with carboxyfluorescein diacetate succinimidyl ester (CFDA-SE) before transplantation. The animal models of UUO were used. Histological changes in renal tubular interstitium were observed with HE and Masson staining. The protein levels of vascular endothelial growth factor(VEGF), hypoxia inducible factor-1alpha (HIF-1alpha) and connective tissue growth factor (CTGF) were analyzed by western blotting and immunohistochemistry. Transforming growth factor-beta1 (TGF-beta1) was detected by immunohistochemistry. Peritubular capillary (PTC) density was determined by CD31 immunostaining. KEY FINDINGS: Transplanted BM-EPCs were successfully incorporated into the capillary network in the obstructed kidney in vivo. UUO induced a significant decrease in VEGF levels and PTC density in the kidney tissue, which was accompanied by a significant increase in HIF-1alpha, CTGF and TGF-beta1. Transplantation of BM-EPCs increased PTC density, VEGF expression and alleviated the development of renal interstitial fibrosis in UUO mice. No significant pathological changes were found in control mice. SIGNIFICANCE: The reduction of PTC density and up-regulation of HIF-1alpha are the important mechanisms of interstitial fibrosis in UUO mice. BM-EPCs transplantation may increase the number of capillary density and alleviate the development of renal fibrosis in obstructive nephropathy in mice.