Regulation of autophagy by store-operated calcium channel in arterial smooth muscle cells / 中国药理学通报

ABSTRACT

Aim To investigate the effect of store-oper-ated calcium channel( SOCC) on autophagy in rat arte-rial smooth muscle cells A7 R5 . Methods Lentiviruses containing STIM1 or Orai1 gene were packaged in 293 T cells and then were used to infect rat arterial smooth muscle cells A7 R5 . The expression levels of STIM1 , Orai1 and Beclin 1 , a critical autophagy-regu-lating protein, of lentivirus-infected A7R5 cells, were detected by Western-blot. Autophagy in lentivirus-in-fected A7 R5 cells was induced by starvation or rapamy-cin, an inhibitor of mammalian target of rapamycin ( mTOR ) . Autophagy marker LC3 of these cells was detected by Western-blot. Results The constructions of vector pLV-STIM1 and pLV-Orai1 were confirmed by restriction enzymes digestion analysis. Compared with the control group, expressions of STIM1 or Orai1 protein was significantly increased after lentivirusLV-STIM1 and LV-Orai1infection, whereas the expressions of autophagy related protein Beclin-1 were down-regu-lated. Starvation or rapamycin stimulated A7R5 auto-phagy but overexpression of STIM1 or Orai1 significant-ly inhibited starvation or rapamycin induced autoph-agy. Conclusion Overexpression of store-operated calcium channel components STIM1 and/or Orai1 in rat arterial smooth muscle cells A7 R5 inhibit autoph-agy. This mechanism might contribute to the develop-ment of pulmonary arterial hypertension.