The axis of miR-30a/AIF-1/TRPC6/calcineurin A/NFAT2 regulated the death modalities and inflammation of renal tubular epithelial cells in diabetic kidney disease via exosome

Aims

Diabetic kidney disease (DKD) is a significant complication of diabetes, marked by inflammation, fibrosis, and cell death in renal tissues. This study aimed to elucidate the regulatory role of miR-30a in DKD, focusing on its impact on monocyte/macrophage activity, key protein expression, exosomes, and renal cell death modalities.

Materials and methods

Using db/db mice as a DKD model, miR-30a expression was manipulated through knockout and overexpression techniques. Macrophage activity was evaluated via F4/80 expression and the M1/M2 macrophage ratio. Key proteins (AIF-1, TRPC6, calcineurin A, NFAT2, and NLRP3) were measured in renal tissues and exosomes from blood and urine. In vitro, TCMK-1 cells under high-glucose conditions were used to assess cell death modalities, including autophagy, apoptosis, pyroptosis, and necrosis.

Key findings

miR-30a inhibited macrophage activity, with increased F4/80 expression in knockout groups and decreased levels in overexpression groups. The M1/M2 macrophage ratio rose in knockout groups and fell in overexpression groups. miR-30a overexpression reduced key protein levels and urinary albumin (ALB), indicating a protective effect against DKD. Exosome concentration and protein content decreased in miR-30a-overexpressing mice. In vitro findings supported these results, highlighting miR-30a's regulatory effects on AIF-1, Caspase 3, TRPC6, Calcineurin A, NFAT2, and cell death modalities. Exosome secretion from TCMK-1 or RAW264.7 cells was affected by high-glucose conditions, influencing cell death modalities and functions of TCMK-1 cells.

Significance

The axis of miR-30a/AIF-1/TRPC6/calcineurin A/NFAT2 regulated death modalities and inflammation of renal tubular epithelial cells in DKD via exosome. miR-30a might be a novel therapeutic target to slow DKD.