Role of Bone Morphogenetic Proteins-7 (BMP-7) in the Renal Improvement Effect of DangGui (Angelica sinensis) in Type-1 Diabetic Rats

Protective effects of Danggui Buxue Tang on renal function, renal glomerular mesangium and heparanase expression in rats with streptozotocin-induced diabetes mellitus

Danggui Buxue Tang (DBT) is a simple combination of Radix Astragali and Radix Angelica sinensis (5:1), with a variety pharmacological activities. In the present study, a single intravenous injection of 30 mg/kg streptozotocin and subsequent six weeks of high glucose diet in Sprague Dawley rats were used to induce diabetic nephropathy. Rats with diabetes mellitus showed increased levels of fasting blood glucose (FBG), blood urea nitrogen (BUN), serum creatinine (Scr), serum and urine β2-microglobulins (β2-MG), and type IV collagen (all P<0.05). DBT treatment significantly decreased the levels of FBG, BUN, Scr, serum and urine β2-MG, and type IV collagen. Furthermore, DBT treatment significantly and dose-dependently restored the ultrastructural injury, and reduced the expression of heparanase, compared with the vehicle (P<0.05). Therefore, DBT may be a novel therapeutic approach for the prevention and treatment of diabetic nephrology.

Curcumin-loaded polymeric nanoparticles for enhanced anti-colorectal cancer applications

The purpose of the present study was to fabricate polymeric nanoparticles as drug carriers for encapsulated curcumin with enhanced anti-colorectal cancer applications. Nanoparticles were formulated from chitosan and gum arabic, natural polysaccharides, via an emulsification solvent diffusion method. The formation of curcumin nanoparticles was confirmed by Fourier transform infrared spectroscopy and differential scanning calorimeter. The results show that curcumin was entrapped in carriers with +48 mV, 136 nm size, and high encapsulation efficiency (95%). Based on an in vitro release study, we inferred that curcumin nanoparticles could tolerate hydrolysis due to gastric juice or small intestinal enzymes, and therefore, it should reach the colon largely intact. In addition, curcumin nanoparticles had higher anti-colorectal cancer properties than free curcumin due to greater cellular uptake. Therefore, we concluded that curcumin was successfully encapsulated in chitosan-gum arabic nanoparticles with superior anti-colorectal cancer activity.

Curcumin protects renal tubular epithelial cells from high glucose-induced epithelial-to-mesenchymal transition through Nrf2-mediated upregulation of heme oxygenase-1

Curcumin has been observed to exhibit an anti-fibrotic effect in the liver, lung and gallbladder. However, the mechanisms underlying the cytoprotective effects of curcumin remain to be elucidated. The epithelial-to-mesenchymal transition (EMT) of mature tubular epithelial cells in the kidney is considered to contribute to the renal accumulation of matrix proteins associated with diabetic nephropathy. The EMT is also closely associated with the progression of renal interstitial fibrosis and oxidative stress. This process may occur through abrogation of high glucose (HG)-induced oxidative stress via activation of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and heme oxygenase-1 (HO-1) in kidney tubular epithelial cells. In the present study, the effect of curcumin on HG-induced EMT in the NRK-52E normal rat kidney tubular epithelial cell line was investigated, and whether the effect of curcumin was mediated by the induction of Nrf2 and HO-1 expression was examined. The present study revealed that curcumin was able to prevent events associated with EMT, including the downregulation of E-cadherin and the increased expression of α-smooth muscle actin. Further analysis revealed that the expression levels of Nrf2 and HO-1 protein were elevated to a greater extent in the curcumin pretreated NRK-52E cells compared with those of the control. Notably, knockdown of Nrf2 with small interfering RNA prevented the curcumin-induced elevation in expression of HO-1 and the associated anti-fibrotic effects. In conclusion, the present findings suggested that curcumin may be significant in cellular antioxidant defense, through the activation of Nrf2 and HO-1, thereby protecting the NRK-52E cells from HG-induced EMT.

Bone morphogenetic protein-5 and early endothelial outgrowth cells (eEOCs) in acute ischemic kidney injury (AKI) and 5/6-chronic kidney disease

Early endothelial outgrowth cells (eEOCs) reproducibly have been shown to act protectively in acute ischemic kidney injury (AKI) and chronic kidney injury. Bone morphogenetic protein-5 (BMP-5) acted antifibrotically in human hypertensive nephropathy. The aim of the current study was to analyze effects of BMP-5 treatment in an eEOC-based therapy of murine AKI and 5/6-nephrectomy. Male C57/Bl6N mice were either subjected to unilateral renal artery clamping postuninephrectomy or to 5/6-nephrectomy. Untreated or BMP-5-pretreated murine eEOCs were injected into recipient animals at the time of reperfusion (AKI) or at 2 and 5 days after 5/6-nephrectomy. Analysis of renal function and morphology was performed at 48 h and at 6 wk (AKI) or at 8 wk (5/6 model). Cellular consequences of eEOC treatment were evaluated using different in vitro assays. AKI was mitigated significantly by injecting BMP-5-pretreated eEOCs. Renal function was improved at 48 h [corrected] after cell therapy. In 5/6-nephrectomy, the cells failed to act renoprotectively, [corrected] but proteinuria was reduced after administering untreated eEOCs." Next, the original version read as "BMP-5 acts as a potent eEOC agonist in murine AKI in the short [corrected] term. Cell effects in 5/6-nephrectomy are heterogenous, but untreated cells act antifibrotically [corrected] without any impact on EnMT.