Rabbit Anti-Human MST1 Polyclonal Antibody

Hippo signaling is a conserved pathway and plays important roles in controlling cell proliferation and differentiation. As a critical component of the Hippo pathway in mammals, mammalian sterile 20-like kinase 1 (MST1) participates in cell apoptosis and cell proliferation. Yes-associated protein (YAP) acts as a downstream transcriptional co-activator of MST1. MST1 is present in heart tissue and helps determine the fate of cardiomyocytes by regulating the balance between autophagy and apoptosis. Recent studies showed MST1 signaling is an essential participant in many cardiovascular disorders, including aortic dissection, aortic aneurysm, atherosclerosis, myocardial ischemic injury, and cardiomyopathy. Previous studies have summarized the roles of MST1 in cardiovascular development. In this review, we focused on the roles of MST1 signaling in cardiovascular disorders.

In this study, we investigated the role of macrophage stimulating 1 (Mst1) and the AMPK-Sirt1 signaling pathway in the oxidative stress-induced mitochondrial dysfunction and apoptosis seen in rheumatoid arthritis-related fibroblast-like synoviocytes (RA-FLSs). Mst1 mRNA and protein expression was significantly higher in hydrogen peroxide (H2O2)-treated RA-FLSs than untreated controls. H2O2 treatment induced the mitochondrial apoptotic pathway by activating caspase3/9 and Bax in the RA-FLSs. Moreover, H2O2 treatment significantly reduced mitochondrial membrane potential and mitochondrial state-3 and state-4 respiration, but increased reactive oxygen species (ROS). Mst1 silencing significantly reduced oxidative stress-induced mitochondrial dysfunction and apoptosis in RA-FLSs. Sirt1 expression was significantly reduced in the H2O2-treated RA-FLSs, but was higher in the H2O2-treated Mst1-silenced RA-FLSs. Pretreatment with selisistat (Sirt1-specific inhibitor) or compound C (AMPK antagonist) significantly reduced the viability and mitochondrial function in H2O2-treated Mst1-silenced RA-FLSs by inhibiting Sirt1 function or Sirt1 expression, respectively. These findings demonstrate that oxidative stress-related upregulation and activation of Mst1 promotes mitochondrial dysfunction and apoptosis in RA-FLSs by inhibiting the AMPK-Sirt1 signaling pathway. This suggests the Mst1-AMPK-Sirt1 axis is a potential target for RA therapy.