Objective To explore the protective effects and underlying mechanism of renalase on high glucose-induced injury in podocytes.

Methods Mouse podocytes were cultured in vitro and divided into control group (5 mmol/L glucose), mannitol group (5 mmol/L glucose + 25 mmol/L D-mannitol), high glucose group (30 mmol/L glucose), and study group (60 μg/mL renalase for 6 hours + 30 mmol/L glucose). After cultured for 48 hours, cells were collected. The mRNA levels of collagen Ⅳα, transforming growth factor β1 (TGF-β1), and monocyte chemoattractant protein 1 (MCP-1) were detected by real-time fluorescence quantitative PCR (qRT-PCR). The activity of caspase-3 and cyclin-dependent kinase inhibitor 1 (p21) and levels of collagen Ⅳα, TGF-β1, MCP-1 were detected by enzyme-linked immunosorbent assay.

Results Compared with the control group, the levels of collagen Ⅳα, TGF-β1, and MCP-1 and the activity of caspase-3 and p21 were significantly increased in podocytes in the high glucose group (P < 0.05). In contrast, the levels of collagen Ⅳα, TGF-β1, and MCP-1, as well as the activity of caspase-3 and p21, were decreased significantly in podocytes in the study group (P < 0.05).

Conclusions Renalase could attenuate high glucose-induced injury in podocytes, of which the mechanism may be related to anti-inflammatory, anti-fibrotic, anti-apoptotic, and reducing p21 activity.