Regulation of MT1-MMP and MMP-2 by leptin in cardiac fibroblasts involves Rho/ROCK-dependent actin cytoskeletal reorganization and leads to enhanced cell migration.

摘要: Altered leptin action has been implicated in the pathophysiology of heart failure obesity, a hallmark which is extracellular matrix remodeling. Here, we characterize direct influence on metalloproteinase (MMP) activity primary adult rat cardiac fibroblasts and focus elucidating molecular mechanisms responsible. Leptin increased expression cell surface localization membrane type 1 (MT1)-MMP, measured by biotinylation assay antibody-based colorimetric detection an exofacial epitope intact cells. Coimmunoprecipitation analysis showed that also induced formation cluster differentiation 44/MT1-MMP complex. Qualitative using rhodamine-conjugated phalloidin immunofluorescence indicated stimulated actin cytoskeletal reorganization enhanced stress fiber formation. Hence, analyzed activation Ras homolog gene family (Rho), member A GTPase found rapid increase response to corresponded with phosphorylation cofilin. Quantitative cytoskeleton upon separation globular filamentous differential centrifugation confirmed significant ratio leptin, was prevented pharmacological inhibition Rho (C3 transferase) or its downstream effector kinase Rho-associated coiled-coil-forming protein (ROCK) (Y-27632). Inhibition ROCK attenuated leptin-stimulated increases MT1-MMP content. Pro-MMP-2 known substrate, observed resulted pro-MMP-2 gelatin zymography, again ROCK. Using wound scratch assays, migration, but not proliferation, 5-bromo2'-deoxy-uridine incorporation, via Rho-dependent signaling mechanism. Our results suggest regulates myocardial remodeling regulating Rho/ROCK-dependent reorganization. Subsequent then contributes stimulation migration.