Rho-kinase inhibitor restores glomerular fatty acid metabolism in diabetic kidney disease.

The small GTPase Rho and its effector Rho-kinase (ROCK) are activated in the diabetic kidney, and recent studies decade have demonstrated that ROCK signaling is an integral pathway in the progression of diabetic kidney disease. We previously identified the distinct role of ROCK1, an isoform of ROCK, in fatty acid metabolism in diabetic glomeruli. However, the effect of pharmacological intervention for ROCK1 is not clear. In the present study, we show that the inhibition of ROCK1 by Y-27632 and fasudil restores fatty acid oxidation in the glomeruli. Mechanistically, these compounds optimize fatty acid utilization and redox balance in mesangial cells via AMPK phosphorylation and the subsequent induction of PGC-1α. A further in vivo study showed that the inhibition of ROCK1 suppressed the downregulation of the fatty acid oxidation-related gene expression in glomeruli and mitochondrial fragmentation in the mesangial cells of db/db mice. These observations indicate that ROCK1 could be a promising therapeutic target for diabetic kidney disease through a mechanism that improves glomerular fatty acid metabolism.