Description_x000D_ Biochem/physiol Actions_x000D_ AP39 is a anethole dithiolethione (ADT-OH)-derivatized hydrogen sulfide (H2S) donor with a lipophilic & positively charged triphenylphosphonium (TP) moiety for mitochondrially targeted H2S release. AP39 stimulates mitochondrial electron transport and cellular bioenergetic function, protecting against mitochondrial DNA damage and cell death upon oxidative stress induction (effective conc. 30–100 nM; bEnd.3 cells). AP39 in vivo efficacy (0.1-1 μmol/kg i.v.; 0.1-0.3 mg/kg i.p.) is demonstrated in varous rodent models, including neurological damage post cardiac arrest, renal injury post ischemia-reperfusion, burn-caused organ damage, as well as brain atrophy in APP/PS1 mice.