Overexpression of SARAF Ameliorates Pressure Overload-Induced Cardiac Hypertrophy Through Suppressing STIM1-Orai1 in Mice

Cell Physiol Biochem. 2018;47(2):817-826. doi: 10.1159/000490036. Epub 2018 May 22.


Background/aims: Activation of stromal interaction molecule 1 (STIM1) and Orai1 participates in the development of cardiac hypertrophy. Store-operated Ca2+ entry-associated regulatory factor (SARAF) is an intrinsic inhibitor of STIM1-Orai1 interaction. Thus, we hypothesized that SARAF could prevent cardiac hypertrophy.

Methods: Male C57BL/6 mice, aged 8 weeks, were randomly divided into sham and abdominal aortic constriction surgery groups and were infected with lentiviruses expressing SARAF and GFP (Lenti-SARAF) or GFP alone (Lenti-GFP) via intramyocardial injection. At 4 weeks after aortic constriction, left ventricular structure and function were assessed by echocardiography and hemodynamic assays. The gene and protein expressions of SARAF, STIM1, and Orai1 were measured by quantitative PCR and Western blot, respectively.

Results: Gene and protein expressions of SARAF were significantly decreased, while STIM1 and Orai1 were increased in the heart tissue compared with sham group. Overexpression of SARAF in the heart prevented the upregulation of STIM1 and Orai1, and importantly, attenuated aortic constriction-induced decrease in maximal rate of left ventricular pressure decay and increases in thickness of interventricular septum and left ventricular posterior wall, heart weight/body weight ratio, and size of cardiomyocytes. Blood pressure detected through the carotid artery and left ventricular systolic function were not affected by SARAF overexpression. In addition, overexpression of SARAF also attenuated angiotensin II-induced upregulation of STIM1 and Orai1 and hypertrophy of cultured cardiomyocytes.

Conclusion: Overexpression of SARAF in the heart prevents cardiac hypertrophy, probably through suppressing the upregulation of STIM1/Orai1.

Keywords: Store-operated Ca2+ entry-associated regulatory factor; Store-operated calcium entry; Transmembrane protein 66.

MeSH terms

  • Angiotensin II / pharmacology
  • Animals
  • Aorta, Abdominal / surgery
  • Atrial Natriuretic Factor / genetics
  • Atrial Natriuretic Factor / metabolism
  • Cardiomegaly / metabolism
  • Cardiomegaly / pathology
  • Cardiomegaly / prevention & control*
  • Cell Line
  • Echocardiography
  • Male
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Mice
  • Mice, Inbred C57BL
  • Myocardium / metabolism
  • Myocardium / pathology
  • Myocytes, Cardiac / cytology
  • Myocytes, Cardiac / metabolism
  • Myosin Heavy Chains / genetics
  • Myosin Heavy Chains / metabolism
  • Natriuretic Peptide, Brain / genetics
  • Natriuretic Peptide, Brain / metabolism
  • ORAI1 Protein / genetics
  • ORAI1 Protein / metabolism*
  • Pressure
  • Stromal Interaction Molecule 1 / genetics
  • Stromal Interaction Molecule 1 / metabolism*
  • Up-Regulation / drug effects
  • Ventricular Function, Left / physiology


  • Membrane Proteins
  • ORAI1 Protein
  • Orai1 protein, mouse
  • Stim1 protein, mouse
  • Stromal Interaction Molecule 1
  • Angiotensin II
  • Natriuretic Peptide, Brain
  • Atrial Natriuretic Factor
  • Myosin Heavy Chains