Vinexin-β exacerbates cardiac dysfunction post-myocardial infarction via mediating apoptotic and inflammatory responses

Clin Sci (Lond). 2015 Jun;128(12):923-36. doi: 10.1042/CS20140648.

Abstract

Vinexin-β is one of the adaptor proteins that are primarily involved in signal transduction and cytoskeletal organization under various pathological conditions, including cardiac hypertrophy. However, the role of Vinexin-β in myocardial infarction (MI) remains unknown. In this study, dramatically up-regulated Vinexin-β expression was observed in both ischaemic human hearts and infarcted animal hearts. To explore the potential involvement of Vinexin-β in MI further, we induced MI injury in global Vinexin-β-knockout mice and wild-type (WT) controls as well as in mice with cardiac-specific over-expression of the human Vinexin-β gene-transgenic (TG) and -non-transgenic (NTG) littermates. Compared with that observed in WT controls, Vinexin-β deficiency significantly decreased MI-induced infarct size, concomitant with an improved cardiac function, leading to an increase in the survival rate. The myocardial apoptosis in the border zone was dramatically reduced by Vinexin-β deficiency, resulting from the altered expression of apoptotic factors. Furthermore, Vinexin-β depletion mitigated the inflammatory response, as evidenced by reduced inflammatory cell infiltration, decreased expression of cytokines and the inactivation of NF-κB (nuclear factor κB) signalling. In contrast, Vinexin-β-TG mice were much more susceptible to MI injury compared with NTG controls. Further mechanism analyses suggested that Vinexin-β exerted detrimental effects largely dependent on blocking AKT signalling. The effects and mechanisms of Vinexin-β on MI observed in vivo were further confirmed by our in vitro assays. When collected, these data demonstrate for the first time that Vinexin-β increases MI-induced mortality and worsens cardiac dysfunction through aggravation of myocardial apoptosis and inflammatory response.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing / metabolism
  • Adaptor Proteins, Signal Transducing / physiology*
  • Aged
  • Animals
  • Apoptosis / physiology
  • Cell Death / physiology
  • Cell Hypoxia / physiology
  • Humans
  • Inflammation / metabolism*
  • Inflammation / physiopathology
  • Male
  • Mice, Knockout
  • Middle Aged
  • Muscle Proteins / deficiency
  • Muscle Proteins / metabolism
  • Muscle Proteins / physiology*
  • Myocardial Infarction / metabolism*
  • Myocardial Infarction / pathology
  • Myocardial Infarction / physiopathology
  • Myocardial Infarction / surgery
  • Myocardial Ischemia / metabolism
  • Myocytes, Cardiac / pathology
  • Proto-Oncogene Proteins c-akt / metabolism
  • Rats, Sprague-Dawley
  • Signal Transduction / physiology
  • Up-Regulation

Substances

  • Adaptor Proteins, Signal Transducing
  • Muscle Proteins
  • SORBS3 protein, human
  • Sorbs3 protein, mouse
  • Proto-Oncogene Proteins c-akt