Cornuside Ameliorates Diabetic Nephropathy Possibly by Regulating Angiogenesis and MAPK Signaling.

Diabetic nephropathy (DN) is a prevalent diabetic complication seriously threatening patients' health and lives. Cornuside is an iridoid glycoside compound with various pharmacological properties. Nonetheless, whether cornuside has a protective effect against DN remains unillustrated. In this study, a rat model for DN was established by streptozotocin (STZ) injection. Rat podocytes were stimulated with high glucose (HG) to mimic a DN microenvironment in vitro. Several indicators linked to kidney function were evaluated. Periodic Acid-Schiff (PAS) and hematoxylin-eosin staining were implemented for renal histologic analysis. Immunofluorescence staining of CD31 was used for the detection of neovascularization. Western blotting was employed to assess levels of angiogenic factors and MAPK signaling-related proteins in the kidney or podocytes. The results showed that cornuside administration alleviated STZ-elicited renal dysfunction, as evidenced by the reduction in fasting blood glucose, proteinuria, serum creatinine, and blood urea nitrogen. Cornuside attenuated renal pathological lesions in DN rats. Cornuside repressed angiogenesis in DN rat kidney tissues and podocytes. Cornuside blocked MAPK signaling in HG-stimulated podocytes. In conclusion, cornuside alleviates renal injury in DN rats possibly by hindering angiogenesis and MAPK signaling.