Equal number of H9c2 cells were plated in 24-well seahorse culture plate, followed by differentiation to H9c2 cardiomyocytes. After 5 days of differentiation, cells were treated with vehicle or rASPN (1 nM) for 24 hrs followed by seahorse respirometry analysis. OCR was measured at several time points. (A) OCR under basal conditions and after addition of oligomycin, FCCP and antimycin A/Rotenone as indicated. Calculations were done from the traces and compared between two groups and illustrated in bar graph representing (B) basal respiration, (C) Proton leak, (D) Non-mitochondrial respiration, (E) ATP production, (F) Spare respiratory capacity, and (G) Maximal respiration. Data are expressed as mean with SD (n = 3). *p<0.05 and **p<0.01 by unpaired t-test. (H) Representative images of differentiated H9c2 cardiomyocytes treated with either vehicle or rASPN subjected to simulated hypoxia-reoxygenation model and stained with MitoSOX red dye. Psedocolor green was selected during imaging using Keyonce microscope. Control cells were kept under normal culture conditions. (I) Bar graph representing the relative MitoSOX fluorescence intensity compared to control group. Data are expressed as mean with SD and one-way ANNOVA with Turkey’s multiple comparison test, ****p<0.0001, **p<0.001.