Juan Yu1, Wei Yang1, Wei Wang1, Zhuoran Wang1, Yuju Pu1, Hongmei Chen2, Fei Wang3, Jinqiao Qian4. 1. Department of Anesthesiology, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan Province, China. 2. Department of Anesthesiology, Kunming Angel Women's & Children's Hospital, Kunming, Yunnan Province, China. 3. Department of Neurosurgery, First Affiliated Hospital of Kunming Medical University, Kunming, China. 4. Department of Anesthesiology, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan Province, China. Electronic address: qianjinqiao@126.com.
Abstract
BACKGROUND: Dexmedetomidine (Dex) can confer cardioprotective effects against ischemia/reperfusion (I/R) injury. While there are no studies addressing cardioprotection of Dex via regulation of microRNAs. The purpose of this study was to examine the roles and mechanisms of microRNA in cardioprotection of dexmedetomidine. METHODS: Rat heart Langendorff preparation was established. We assayed expression profiling of miRNAs in perfused rat hearts and predicted Target genes using MiRanda, MiRDB, and TargetScan. Oxide stress (H2O2) was employed to simulate I/R injury. miR-665 mimic, inhibitor, and siRNA of AK1 and Cnr2 were transfected to H9C2. The real-time quantitative polymerase chain reaction was used to quantify miR-665 and Ak1 and Cnr2 mRNA. The apoptosis of the cells was examined. The expression levels of cleaved caspase-3, Bcl-2, Bax, AK1, and Cnr2 were detected by Western blot. The combination between miR-665 and the 3'-untranslated region of AK1 and Cnr2 was validated by a luciferase reporter assay. RESULTS: Dex precondition down-regulated miR-665 expression in hearts compared to I/R group. Dex reduced miR-665 expression and apoptosis increased by oxide stress. However, up-regulation of miR-665 exacerbated the changes caused by oxide stress and inhibited the effects of Dex. Down-regulation of miR-665 also reduced apoptosis, but inhibition of AK1 and Cnr2 aggravated apoptosis. The luciferase reporter assay indicated that miR-665 could down-regulate expression levels of AK1 and Cnr2. CONCLUSIONS: Dex precondition confers hearts protective effect against I/R injury by down-regulating expression of miR-665 and up-regulating expression of AK1 and Cnr2.
BACKGROUND:Dexmedetomidine (Dex) can confer cardioprotective effects against ischemia/reperfusion (I/R) injury. While there are no studies addressing cardioprotection of Dex via regulation of microRNAs. The purpose of this study was to examine the roles and mechanisms of microRNA in cardioprotection of dexmedetomidine. METHODS:Rat heart Langendorff preparation was established. We assayed expression profiling of miRNAs in perfused rat hearts and predicted Target genes using MiRanda, MiRDB, and TargetScan. Oxide stress (H2O2) was employed to simulate I/R injury. miR-665 mimic, inhibitor, and siRNA of AK1 and Cnr2 were transfected to H9C2. The real-time quantitative polymerase chain reaction was used to quantify miR-665 and Ak1 and Cnr2 mRNA. The apoptosis of the cells was examined. The expression levels of cleaved caspase-3, Bcl-2, Bax, AK1, and Cnr2 were detected by Western blot. The combination between miR-665 and the 3'-untranslated region of AK1 and Cnr2 was validated by a luciferase reporter assay. RESULTS:Dex precondition down-regulated miR-665 expression in hearts compared to I/R group. Dex reduced miR-665 expression and apoptosis increased by oxide stress. However, up-regulation of miR-665 exacerbated the changes caused by oxide stress and inhibited the effects of Dex. Down-regulation of miR-665 also reduced apoptosis, but inhibition of AK1 and Cnr2 aggravated apoptosis. The luciferase reporter assay indicated that miR-665 could down-regulate expression levels of AK1 and Cnr2. CONCLUSIONS:Dex precondition confers hearts protective effect against I/R injury by down-regulating expression of miR-665 and up-regulating expression of AK1 and Cnr2.
Authors: Timo Z Nazari-Shafti; Vasileios Exarchos; Héctor Rodriguez Cetina Biefer; Nikola Cesarovic; Heike Meyborg; Volkmar Falk; Maximilian Y Emmert Journal: Front Bioeng Biotechnol Date: 2020-03-20