Invited Review ArticleSulfur Dioxide: An Endogenous Protector Against Myocardial InjuryZhou, Dan MD*,†,‡; Zhang, Yong MD†; Du, Junbao MD*,§; Jin, Hongfang PhD*,‡; Tang, Chaoshu PhD§,║; Huang, Yaqian PhD*Author Information *Department of Pediatrics, Peking University First Hospital, Beijing, China; †Department of Cardiology, Wuhan Children's Hospital, Wuhan, Hubei, China; ‡Research Unit of Clinical Diagnosis and Treatment of Pediatric Syncope and Cardiovascular Diseases, Chinese Academy of Medical Sciences, Beijing, China; §Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, China; and ║Department of Physiology and Pathophysiology, Peking University Health Science Center, Beijing, China. Reprints: Hongfang Jin, PhD or Yaqian Huang, PhD, Department of Pediatrics, Peking University First Hospital, Beijing 100034, China (e-mail: email@example.com or firstname.lastname@example.org) or Chaoshu Tang, PhD, Department of Physiology and Pathophysiology, Peking University Health Science Center, Beijing 100191, China (e-mail: email@example.com). Supported by National Natural Science Foundation of China (81622004, 81770278), Beijing Natural Science Foundation (7171010, 7191012, 7182168), and Open Funding from Beijing Key Laboratory of Hypertension Research. The authors report no conflicts of interest. D. Zhou and Y. Zhang contributed equally to this work. Journal of Cardiovascular Pharmacology: October 2020 - Volume 76 - Issue 4 - p 389-396 doi: 10.1097/FJC.0000000000000882 Buy Metrics Abstract Sulfur dioxide (SO2) was previously known as a harmful gas in air pollution. Recently, it was reported that SO2 can be endogenously generated in cardiovascular tissues. Many studies have revealed that endogenous SO2 has important physiological and pathophysiological significance and pharmacological potential. As a novel gasotransmitter, SO2 has important regulatory effects on the heart. It has a dose-dependent negative inotropic effect on cardiac function, in which L-type calcium channels are involved. SO2 can also attenuate myocardial injury caused by various harmful stimuli and play an important role in myocardial ischemia-reperfusion injury and myocardial hypertrophy. These effects are thought to be linked to its ability to reduce inflammation and as an antioxidant. In addition, SO2 regulates cardiomyocyte apoptosis and autophagy. Therefore, endogenous SO2 plays an important role in maintaining cardiovascular system homeostasis. In the present review, the literature concerning the metabolism of endogenous SO2, its cardiac toxicological effects and physiological regulatory effects, mechanisms for SO2-mediated myocardial protection and its pharmacological applications are summarized and discussed. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.