Protective Effect of Tempol on Buthionine Sulfoximine-Induced Mitochondrial Impairment in Hippocampal Derived HT22 Cells

Using a simulated oxidative stress model of hippocampus‐derived immortalized cell line (HT22), we report that prooxidant buthionine sulfoximine (BSO, 1 mM, 14 h), without adversely affecting cell viability or morphology, induced oxidative stress by inhibiting glutathione synthesis. BSO treatment also significantly reduced superoxide dismutase (SOD) activity ( p < 0.05) and significantly lowered total antioxidant capacity ( p < 0.001) in HT22 cells when compared to vehicle treated control cells. Antioxidant tempol, a piperidine nitroxide considered a SOD mimetic, reversed BSO‐induced decline in SOD activity ( p < 0.01) and also increased BSO‐induced decline in total antioxidant capacity ( p < 0.05). Interestingly, BSO treatment significantly reduced mitochondrial oxygen consumption ( p < 0.05), decreased mitochondrial membrane potential ( p < 0.05), and lowered ATP production ( p < 0.05) when compared to vehicle treated control cells, collectively indicative of mitochondrial impairment. Antioxidant tempol treatment mitigated all three indicators of mitochondrial impairment. We postulate that BSO‐induced oxidative stress in HT22 cells caused mitochondrial impairment, and tempol by increasing SOD activity and improving antioxidant capacity presumably protected the cells from BSO‐induced mitochondrial impairment. In conclusion, present study provides an interesting simulation of oxidative stress in hippocampal cells, which will serve as an excellent model to study mitochondrial functions.