Beetroot juice reduces infarct size and improves cardiac function following ischemia–reperfusion injury: Possible involvement of endogenous H 2 S

• Published in: Experimental biology and medicine (Maywood, N.J.) N.J.), 2015-05, Vol.240 (5), p.669-681
• Main Authors: Salloum, Fadi N, Sturz, Gregory R, Yin, Chang, Rehman, Shabina, Hoke, Nicholas N, Kukreja, Rakesh C, Xi, Lei
• Format: Article
• Language: English
• ISSN: 1535-3702; 1535-3699
• DOI: 10.1177/1535370214558024

Ingestion of high dietary nitrate in the form of beetroot juice (BRJ) has been shown to exert antihypertensive effects in humans through increasing cyclic guanosine monophosphate (cGMP) levels. Since enhanced cGMP protects against myocardial ischemia–reperfusion (I/R) injury through upregulation of hydrogen sulfide (H 2 S), we tested the hypothesis that BRJ protects against I/R injury via H 2 S. Adult male CD-1 mice received either regular drinking water or those dissolved with BRJ powder (10 g/L, containing ∼0.7 mM nitrate). Seven days later, the hearts were explanted for molecular analyses. Subsets of mice were subjected to I/R injury by occlusion of the left coronary artery for 30 min and reperfusion for 24 h. A specific inhibitor of H 2 S producing enzyme – cystathionine-γ-lyase (CSE), dl-propargylglycine (PAG, 50 mg/kg) was given i.p. 30 min before ischemia. Myocardial infarct size was significantly reduced in BRJ-fed mice (15.8 ± 3.2%) versus controls (46.5 ± 3.5%, mean ± standard error [ SE], n = 6/group, P