Melatonin inhibits vascular smooth muscle cell proliferation and apoptosis through upregulation of Sestrin2

Seunghyeong Lee; Jun-Kyu Byun; Mihyang Park; Sung Woo Kim; Sungwoo Lee; Jung-Guk Kim; In-Kyu Lee; Yeon-Kyung Choi; Keun-Gyu Park

doi:10.3892/etm.2020.8638

Melatonin inhibits vascular smooth muscle cell proliferation and apoptosis through upregulation of Sestrin2

Exp Ther Med. 2020 Jun;19(6):3454-3460. doi: 10.3892/etm.2020.8638. Epub 2020 Apr 2.

Authors

Seunghyeong Lee^{1

2}, Jun-Kyu Byun^{3

4}, Mihyang Park^{1

2}, Sung Woo Kim⁵, Sungwoo Lee⁶, Jung-Guk Kim⁴, In-Kyu Lee⁴, Yeon-Kyung Choi⁴, Keun-Gyu Park^{1

3

4}

Affiliations

¹ Department of Biomedical Science, Graduate School, Kyungpook National University, Daegu 41566, Republic of Korea.
² BK21 Plus KNU Biomedical Convergence Program, Kyungpook National University, Daegu 41566, Republic of Korea.
³ Research Institute of Aging and Metabolism, Kyungpook National University, Daegu 41566, Republic of Korea.
⁴ Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu 41944, Republic of Korea.
⁵ Department of Internal Medicine, Catholic University of Daegu School of Medicine, Daegu 42472, Republic of Korea.
⁶ New Drug Development Center, Daegu-Gyeongbuk Medical Innovation Foundation, Daegu 41061, Republic of Korea.

Abstract

Excessive vascular smooth muscle cell (VSMC) proliferation contributes to the development of atherosclerosis and restenosis. Furthermore, apoptosis of VSMCs accelerates plaque rupture in the atherosclerotic vessels. Therefore, a strategy that regulates both VSMC proliferation and apoptosis is essential for the development of novel pharmacological tools for the treatment of atherosclerosis. Despite mounting evidence supporting the benefits of melatonin in diverse metabolic diseases, the role of melatonin in VSMC growth remains largely unknown. The present study revealed that melatonin inhibited both proliferation and apoptosis of primary cultured rat VSMCs. Melatonin induced mitochondrial energetic stress in VSMCs and subsequent induction of Sestrin2 via C/EBPβ. Melatonin-induced Sestrin2 suppressed mTORC1 activity in VSMCs, contributing to suppression of VSMC proliferation. Additionally, melatonin-induced upregulation of Sestrin2 blocked apoptosis by preventing excessive ROS generation. The results demonstrated that melatonin controlled VSMC proliferation and apoptosis via Sestrin2-mediated inhibition of mTORC1 and ROS scavenging. Therefore, melatonin should be considered as a lead compound for therapies aimed at preventing vessel lumen constriction during the course of atherosclerosis and restenosis.

Keywords: Sestrin2; apoptosis; melatonin; proliferation; vascular smooth muscle cells.