RESUMO
Objective @#To investigate the effects and mechanism of small ubiquitin-like modifier ( SUMO) specific proteinase-1 (SENP-1) on chronic intermittent hypoxia ( CIH) induced myocardial injury in rats．@*Methods @# 32 male SD rats were randomly divided into : control group，CIH group，negative control adeno-associated virus interven- tion group (AAV-shNC) and SENP-1 shRNA adeno-associated virus intervention group (AAV-shSENP-1) ，with 8 rats in each group．After 6 weeks of CIH induction，echocardiography was performed．The levels of cardiac troponin I (cTNI) ，creatine kinase MB isoenzyme ( CKMB) ，myoglobin (Mb) ，lactate dehydrogenase (LDH) in serum and malondialdehyde (MDA) ，uperoxide dismutases ( SOD) ，glutathione ( GSH) ，interleukin( IL) -1 β , IL-6 and tumor necrosis factor-α(TNF-α) in myocardial tissue were detected by ELISA．The pathological changes of myocardial tis- sue was observed by HE staining．The reactive oxygen species ( ROS) level in myocardial tissue was detected by DCFH-DA fluorescence probe labeling．The small ubiquitin-like modifier (SUMO) level of hypoxia inducible factor- 1 α (HIF-1 α) protein in myocardial tissue was detected by kit．The mRNA and protein levels of SENP-1 and HIF- 1 α in myocardial tissue were detected by qRT-PCR and Western blot. @*Results @# Compared with the control group， the pathological damage of myocardial tissue in CIH group was serious，the levels of left ventricular end diastolic diameter (LVEDD) ，left ventricular end systolic dimension (LVESD) and serum cTNI，CKMB，Mb and LDH signif- icantly increased (P＜0. 05) ，and the levels of ROS，MDA，IL-1 β , IL-6，TNF-α and the mRNA and protein levels of SENP-1 and HIF-1α in myocardial tissue also significantly increased (P ＜0. 05 ) ，while the levels of LVEF， LVFS，serum GSH and SOD significantly decreased (P ＜0. 05) ，and the SUMOylates level of HIF-1α protein in myocardial tissue also significantly decreased (P ＜0. 05 ) ．Compared with CIH group，AAV-shSENP-1 group had less myocardial pathological damage，the levels of LVEDD，LVESD and serum cTNI，CKMB，Mb and LDH signifi- cantly decreased (P＜0. 05) ，and the levels of ROS，MDA，IL-1 β, IL-6，TNF-α and the mRNA and protein levels of SENP-1 and HIF-1α in myocardial tissue also significantly decreased (P＜0. 05) ，the levels of LVEF，LVFS，serum GSH and SOD significantly increased (P＜0. 05) ，and the SUMOylates level of HIF-1α protein in myocardial tissue also significantly decreased (P＜0. 05) ． @*Conclusion @# Inhibition of SENP-1 expression can alleviate CIH induced myocarditis and oxidative stress in rats，improve myocardial injury and cardiac dysfunction，and its mechanism may be related to the improvement of HIF-1α SUMOylates level，thus inhibiting HIF-1α expression.