Salidroside from Rhodiola rosea L. has hypoglycemic effects, and has anti-osteoporosis effect in diabetic rats. Whether it has beneficial effects on diabetic nephropathy (DN) has not been fully reported. Here, a DN rat model was established by streptozotocin (STZ). Salidroside (10, and 20 mg kg −1 d −1 ) were orally giving for eight weeks. The purity of salidroside was 99%. The results showed that eight weeks salidroside supplementation dose-dependently decreased blood glucose, serum insulin, serum creatinine, blood urea nitrogen (BUN), as well as urinary albumin of DN rats, repaired the pathological changes of kidney tissue, the renal sclerosis and fibrosis in the kidney of DN rats were improved, and the activities of oxidative defense system associated enzyme such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) were also improved. Serum inflammatory cytokines (including tumor necrosis factor-α, monocyte chemoattractant protein-1, interleukin-1β, and interleukin-6) were decreased significantly in DN rats after eight weeks salidroside supplementation. Immunohistochemical results showed that fibrosis related proteins such as transforming growth factor-β1 (TGF-β1), phospho-Smad2 (p-Smad2), and phospho-Smad3 (p-Smad3) expression levels were decreased significantly in the kidney of salidroside treated group. Our results indicate that daily salidroside consumption could alleviate DN in rats, the main mechanisms are anti-inflammatory, anti-oxidative stress, and inhibition of the TGF-β1/Smad2/3 pathway. This study suggested that salidroside could be used as a nutrient against DN, as well as diabetes.
Du Lifen,Lei Yongfang,Chen Jinglou,Song Hongping,Wu Xinying
Background/Aims: Cadmium (Cd) is an environmental pollutant with reproductive toxicity. Swertia mileensis is used in Chinese medicine for the treatment of prostatic deficits and named as Qing Ye Dan (QYD). This study was undertaken to investigate the potential protective effects of QYD against Cd-induced prostatic deficits. Method: Rat model of prostatic deficits was induced by 0.2 mg/kg/d CdCl2 subcutaneous injection for 15 days. The prostatic oxidative stress was evaluated by detecting the levels of malondialdehyde, nitric oxide, reduced/ oxidized glutathione, total sulfhydryl groups and enzymatic antioxidant status. The prostatic inflammation was estimated by testing the levels of pro-inflammatory cytokines. The levels of epithelial-mesenchymal transition (EMT) markers E-cadherin, fibronectin, vimentin and α-smooth muscle actin were measured by qPCR analysis. Additionally, the prostatic expressions of transforming growth factor-β1 (TGF-β1), type I TGF-β receptor (TGF-βRI), Smad2, phosphorylation-Smad2 (p-Smad2), Smad3, p-Smad3, Smad7, nuclear related factor-2 (Nrf-2), heme oxygenase-1 (HO-1), B-cell CLL/lymphoma (Bcl)-2 and Bcl-2-associated X protein (Bax) were measured by western blot assay. Results: It was found that QYD ameliorated the Cd-induced prostatic oxidative stress and inflammation, attenuated prostatic EMT, inhibited the TGF-β1/Smad pathway, increased Bcl-2/Bax ratio and enhanced the activity of Nrf-2/HO-1 pathway. Conclusion: These results showed that QYD could ameliorate Cd-induced prostatic deficits via modulating Nrf-2/HO-1 and TGF-β1/Smad pathways