Hydrogen sulfide (H2S) has recently been identified as a physiologically important endogenous gaseous signaling molecule with a diverse array of biological activities. H2S is produced in micromolar quantities by two endogenous enzymes, cystathionine 3lyase (CGL) and cystathionine 2 synthase (CBS) and is critical for the maintenance of cardiovascular homeostasis. H2S attenuates leukocyte adhesion, modulates mitochondrial respiration, and inhibits both apoptosis, and oxidative stress. These physiological actions are ideal for the treatment of myocardial ischemia-reperfusion (MI-R) injury. Preliminary data clearly demonstrate that physiological levels of H2S significantly ameliorate MI-R injury and preserve left ventricular function. Preliminary data also indicate that H2S therapy triggers both """"""""early"""""""" and """"""""late"""""""" myocardial preconditioning. We also demonstrate that mice with cardiac-restricted CGL overexpression exhibit significantly increased myocardial H2S bioavailability and protection against myocardial I-R injury. The central hypothesis for the proposed studies is that H2S triggers a cardioprotective signaling cascade that confers robust cardioprotection in the setting of MI-R injury. The proposed studies will evaluate the various cardioprotective signals induced by H2S therapy during both """"""""acute"""""""" and """"""""chronic"""""""" pharmacological preconditioning as well as the during acute H2S therapy at the time of reperfusion.
Specific Aim 1 : To investigate the contribution of ATP sensitive K+ channels (KATP channels) in H2S- mediated cardioprotection against myocardial ischemia-reperfusion injury. In vitro studies will evaluate the effects of H2S on KATP channel activation and mitochondrial function. In vivo Studies will be performed using gene-targeted mice with cardiac myocyte deletion of KATP (Sur 1, Kir 6.1, and Kir 6.2 subunits) treated with H2S and subjected to MI-R.
Specific Aim 2 : To investigate the role of antioxidants in H2S-mediated cardioprotection. Studies will evaluate the acute and chronic effects of H2S on Nrf-2 activation and oxidative stress during MI-R. Studies will also investigate the effects of H2S on the induction of antioxidant signaling pathways in the myocardium prior to MI-R.
Specific Aim 3 : To investigate the role of the RISK pathway in H2S-mediated cardioprotection. Studies will investigate the effects of H2S on RISK pathway (PI3K, Akt, PKC5, and Erk 1/2) activation, downstream anti-apoptotic signaling, MPTP opening, and myocardial cell death following MI-R. The proposed studies will significantly extend our current understanding of the molecular and cellular pathophysiology of MI-R injury and provide the foundation for the development of H2S therapy for the treatment of acute myocardial infarction.

Public Health Relevance

Despite numerous advances in health care, cardiovascular disease remains the number one killer in the United States and acute myocardial infarction (i.e., heart attack) affects nearly 1.1 million people every year and is responsible for approximately 220,000 deaths per year in the United States. The proposed studies will evaluate the efficacy of a novel therapeutic agent (i.e., hydrogen sulfide) in a clinically relevant and highly translational experimental model system of acute myocardial infarction. Experiments will determine the precise cellular mechanisms by which hydrogen sulfide protects the heart against acute myocardial infarction. Additional studies will examine the effects of genetic overexpression of a critical hydrogen sulfide generating enzyme on the severity of acute myocardial infarction. The proposed studies will significantly advance our current understanding of the mechanisms responsible for myocardial cell death during a heart attack. Information gained from these studies will help with the development of novel therapies for the treatment of patients suffering from acute myocardial infarction.

National Institute of Health (NIH)
National Heart, Lung, and Blood Institute (NHLBI)
Research Project (R01)
Project #
Application #
Study Section
Special Emphasis Panel (ZRG1-CVS-P (02))
Program Officer
Liang, Isabella Y
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Emory University
Schools of Medicine
United States
Zip Code
Lindsey, Merry L; Bolli, Roberto; Canty Jr, John M et al. (2018) Guidelines for experimental models of myocardial ischemia and infarction. Am J Physiol Heart Circ Physiol 314:H812-H838
Shimizu, Yuuki; Polavarapu, Rohini; Eskla, Kattri-Liis et al. (2018) Hydrogen sulfide regulates cardiac mitochondrial biogenesis via the activation of AMPK. J Mol Cell Cardiol 116:29-40
Lefer, David J; Marbán, Eduardo (2017) Is Cardioprotection Dead? Circulation 136:98-109
Zheng, Yueqin; Yu, Bingchen; Li, Zhen et al. (2017) An Esterase-Sensitive Prodrug Approach for Controllable Delivery of Persulfide Species. Angew Chem Int Ed Engl 56:11749-11753
Tejada, Thor; Tan, Lin; Torres, Rebecca A et al. (2016) IGF-1 degradation by mouse mast cell protease 4 promotes cell death and adverse cardiac remodeling days after a myocardial infarction. Proc Natl Acad Sci U S A 113:6949-54
Bradley, Jessica M; Organ, Chelsea L; Lefer, David J (2016) Garlic-Derived Organic Polysulfides and Myocardial Protection. J Nutr 146:403S-409S
Polhemus, David J; Gao, Juan; Scarborough, Amy L et al. (2016) Radiofrequency Renal Denervation Protects the Ischemic Heart via Inhibition of GRK2 and Increased Nitric Oxide Signaling. Circ Res 119:470-80
Organ, Chelsea L; Otsuka, Hiroyuki; Bhushan, Shashi et al. (2016) Choline Diet and Its Gut Microbe-Derived Metabolite, Trimethylamine N-Oxide, Exacerbate Pressure Overload-Induced Heart Failure. Circ Heart Fail 9:e002314
Polhemus, David J; Bradley, Jessica M; Islam, Kazi N et al. (2015) Therapeutic potential of sustained-release sodium nitrite for critical limb ischemia in the setting of metabolic syndrome. Am J Physiol Heart Circ Physiol 309:H82-92
Bradley, Jessica M; Islam, Kazi N; Polhemus, David J et al. (2015) Sustained release nitrite therapy results in myocardial protection in a porcine model of metabolic syndrome with peripheral vascular disease. Am J Physiol Heart Circ Physiol 309:H305-17

Showing the most recent 10 out of 42 publications