Danzhi Jiangtang capsule reduces renal injury in rats with diabetes induced by high fat diet and streptozotocin downregulating toll-like receptor 4-nuclear factor-κB pathway and apoptosis.

Objective: To investigate the effect and mechanisms of Danzhi Jiangtang capsule (, DJC) on renal injury in streptozotocin (STZ)-induced diabetes of rats.

Methods: Sprague-Dawley rats were fed with high fat diet for 6 weeks followed by streptozotocin (STZ, 35 mg/kg) injection. These rats were then treated with DJC (270, 540 and 1080 mg/kg) daily for 8 weeks.

Results: A combination of high fat diet and STZ significantly increased blood glucose creatinine, urea nitrogen, and urine albumin in rats. Meanwhile, the glomerular and tubular lesions were observed in rats fed with high fat diet and injected with STZ. These biochemical and pathological changes were significantly attenuated by DJC treatments in a dose-dependent manner. Mechanistically, DJC treatments significantly decreased toll-like receptor 4 (TLR4), mitogen-activated protein kinase (MAPK), and nuclear factor-κB (NF-κB) signals in the kidney of rats fed with high fat diet and injected with STZ. Terminal deoxynucleotidyl transferase dUTP nick end labeling staining and caspase-8 levels showed that renal apoptosis was increased in rats fed with high fat diet and injected with STZ, and this was attenuated by DJC treatments.

Conclusions: DJC treatments protect against diabetic kidney disease, and the mechanism may be closely related to downregulation of TLR4/MAPK/NF-κB pathways and apoptosis. This study provides further evidence of using DJC as a potential therapeutic option for diabetic kidney disease.