Objective To investigate the renal protective effect and mechanism of safflower yellow on streptozotocin-induced diabetic nephropathy in mice.
Methods C57BL/6J male mice were injected with STZ (50 mg/kg) by intraperitoneal injection to establish a diabetic mouse model for 5 consecutive days. The 36 successfully modeled mice were randomly divided into model group and SY low, medium and high dose groups (10 mg/kg, 30 mg/kg, 90 mg/kg). The mice in the administration group were given different doses of SY, once a day, for 10 weeks. The body weight and blood sugar of diabetic mice were monitored, the levels of serum creatinine (Scr) and blood urea nitrogen (BUN) were analyzed, the pathological changes of renal tissue were observed by HE staining, and the protein expressions of PKC, P-Raf, Raf, P-ERK and ERK were detected by Western ELISA kits were used to detect the content of MDA, SOD, GSH and the expression levels of TNF-α, IL-6 and IL-1β.
Results Compared with the normal group, the mice in the model group had increased food intake, increased water intake, body weight loss, and elevated blood sugar. Compared with the model group, the weight of the mice in the administration group increased, the blood sugar decreased, the levels of BUN and Scr were decreased; the glomerular hypertrophy, the thickening of the basement membrane and the vacuolar lesions of the renal tubules were improved; the contents of SOD and GSH increased, The content of MDA decreased; the expressions of TNF-α, IL-6 and IL-1β decreased; the expressions of PKC, P-Raf and P-ERK proteins decreased.
Conclusion Safflower yellow can attenuate DN inflammatory injury and oxidative stress injury, and its mechanism may be related to the regulation of PKC/Ras-Raf-MEK-ERK pathway.