Fig. 5. SQOR improves mitochondrial function in neuronal cells.

a Immunoblots of SQOR in SH-SY5Y with mock transfection or SQOR expression (L, H: low and high dose of transfection agent). Representative immunoblots of 2 independent biological replicates are shown. b Effect of SQOR expression on Intracellular persulfide level in SH-SY5Y cell at 21% O₂. n = 5 each. c ATP levels in mitochondria isolated from SH-SY5Y cells with or without SQOR expression treated with Na₂S at 0, 1, or 3 µM in the medium (n = 6 each). d Intracellular H₂S (n = 12 each), e lactate in cell culture medium (n = 6 each), f intracellular NADH/NAD⁺ ratio (n = 5 each), g intracellular ROS (n = 10 each), h intracellular ATP (n = 6 each), and i complex IV activity (n = 5 each) in SH-SY5Y cells with or without SQOR expression in 21% or 1% O₂. Cells were exposed to hypoxia or normoxia for 3 h starting at 48 h after transfection. Data are presented as mean and individual values. A two-tailed unpaired t-test was performed for b. Two-way ANOVA followed by Sidak’s correction for post-hoc comparisons were performed for c–i.