Lei Yu1, Yingfeng Tu2, Xueling Jia1, Kun Fang1, Li Liu3, Lin Wan4, Chuanying Xiang1, Yanan Wang1, Xiangju Sun2, Tianyou Liu5, Dejun Yu6, Weiwei Cao1, Yinli Song1, Yuhua Fan1. 1. College of Pharmacy, Harbin Medical University-Daqing, Daqing, China. 2. Department of Cardiology, the Fourth Hospital of Harbin Medical University, Harbin, China. 3. Department of Anesthesiology, the Third Hospital of Harbin Medical University, Harbin, China. 4. Department of Breast Surgery, the Third Hospital of Harbin Medical University, Harbin, China. 5. Department of Colorectal Surgery, the First Affiliated Hospital of Harbin Medical University, Harbin, China. 6. Department of Laboratory Diagnosis, the fifth affiliated hospital of Harbin Medical University, Daqing, China.
Abstract
BACKGROUND/ OBJECTIVES: The polyphenol resveratrol (Rev) has been found to exhibit various beneficial effects including prevention of pulmonary arterial hypertension (PAH). The present study was designed to investigate the action and potential mechanism of Rev on PAH, focusing on the role of SIRT1 (Silent Information Regulator 1) in apoptosis of pulmonary artery smooth muscle cells (PASMCs). METHODS: PAH rats were established by exposure to hypoxia for 21 days. Rev and SRT1720 (a selective SIRT1 activator) were used to reverse PAH by gavaging rats. PASMCs were confronted with hypoxia for 24 h or 48 h and were then treated with Rev or SRT1720 in vitro. Western blot was performed to detect the protein expression of SIRT1. CCK-8 and scratch wound experiments were carried out to verify cell proliferation. In addition, the TUNEL positive assay and flow cytometry assay were used to measure PASMC apoptosis. Mitochondrial permeability transition (mPT) was identified by confocal microscopy. Right ventricular systolic pressure (RVSP) was determined with a Gould pressure transducer, and right ventricular hypertrophy (RVH) was determined by weighing the cardiac muscle. RESULTS: We demonstrated that Rev could reverse the remodelling of the pulmonary vasculature, thus contributing to alleviating the severity of PAH. Down-regulation of SIRT1 was observed in PAH, but administration of Rev had no obvious effect on the protein expression of SIRT1. In addition, Rev could induce mitochondrial swelling and nuclear pyknosis, leading to small, dense, and dysmorphic mitochondria in rats exposed to hypoxia alone. Rev treatment inhibited PASMC proliferation in a dose-dependent manner in vitro. Incubation with SRT1720, a specific activator of SIRT1, significantly retarded PASMC proliferation and promoted PASMC apoptosis in vitro. The mechanism could be associated with inducing mPT damage in PASMCs. Rev and SRT1720 treatment mitigated RVSP and reduced RVH. CONCLUSION: Rev produced a beneficial effect partially by enhancing the activation of SIRT1, thus improving RVSP and reducing RVH. SIRT1 activation increased PASMC apoptosis by inducing mPT dysfunction, which might be a novel future strategy for the treatment of PAH.
BACKGROUND/ OBJECTIVES: The polyphenolresveratrol (Rev) has been found to exhibit various beneficial effects including prevention of pulmonary arterial hypertension (PAH). The present study was designed to investigate the action and potential mechanism of Rev on PAH, focusing on the role of SIRT1 (Silent Information Regulator 1) in apoptosis of pulmonary artery smooth muscle cells (PASMCs). METHODS: PAH rats were established by exposure to hypoxia for 21 days. Rev and SRT1720 (a selective SIRT1 activator) were used to reverse PAH by gavaging rats. PASMCs were confronted with hypoxia for 24 h or 48 h and were then treated with Rev or SRT1720 in vitro. Western blot was performed to detect the protein expression of SIRT1. CCK-8 and scratch wound experiments were carried out to verify cell proliferation. In addition, the TUNEL positive assay and flow cytometry assay were used to measure PASMC apoptosis. Mitochondrial permeability transition (mPT) was identified by confocal microscopy. Right ventricular systolic pressure (RVSP) was determined with a Gould pressure transducer, and right ventricular hypertrophy (RVH) was determined by weighing the cardiac muscle. RESULTS: We demonstrated that Rev could reverse the remodelling of the pulmonary vasculature, thus contributing to alleviating the severity of PAH. Down-regulation of SIRT1 was observed in PAH, but administration of Rev had no obvious effect on the protein expression of SIRT1. In addition, Rev could induce mitochondrial swelling and nuclear pyknosis, leading to small, dense, and dysmorphic mitochondria in rats exposed to hypoxia alone. Rev treatment inhibited PASMC proliferation in a dose-dependent manner in vitro. Incubation with SRT1720, a specific activator of SIRT1, significantly retardedPASMC proliferation and promoted PASMC apoptosis in vitro. The mechanism could be associated with inducing mPT damage in PASMCs. Rev and SRT1720 treatment mitigated RVSP and reduced RVH. CONCLUSION:Rev produced a beneficial effect partially by enhancing the activation of SIRT1, thus improving RVSP and reducing RVH. SIRT1 activation increased PASMC apoptosis by inducing mPT dysfunction, which might be a novel future strategy for the treatment of PAH.
Authors: Andrew J Bryant; Elnaz Ebrahimi; Amy Nguyen; Christopher A Wolff; Michelle L Gumz; Andrew C Liu; Karyn A Esser Journal: Am J Physiol Lung Cell Mol Physiol Date: 2021-12-01 Impact factor: 5.464