Parthanatos is involved in bupivacaine induced injury in SH-SY5Y cells

Bupivacaine is one of the most toxic local anesthetics. An increasing number of studies have shown that bupivacaine could induce intracellular oxidative stress and cause cell death. However, the mechanisms underlying its neurotoxicity are still unclear. In this study, we evaluate the neurotoxicity effect and the underlying mechanisms of bupivacaine in SH-SY5Y cells. First, we monitored the intracellular reactive oxygen species content after bupivacaine exposure. We also measured the expression level of PARP-1 via western blotting and Quantitative Real-Time PCR methods. Changes in intracellular NAD+ and adenylate depletion were analyzed. We further assessed cell viability and nuclear morphological changes after bupivacaine treatment. Finally, mitochondrial-associated protein expression was examined to verify the pathways of bupivacaine-induced cell death. In addition, mitochondrial membrane potential was also measured by JC-1 staining of SH-SY5Y cells treated with bupivacaine. Results showed that bupivacaine induced reactive oxygen species production and activate PARP-1 expression and PAR polymer formation in SH-SY5Y cells. Bupivacaine-induced PARP-1 activation was associated with intracellular NAD+ utilization and adenylate depletion. Furthermore, bupivacaine was neurotoxic to cells and this toxicity was mitochondrialassociated protein dependent and involved in changes of mitochondrial membrane potential. Collectively, our results suggested that the PARP-1 dependent programmed cell death parthanatos, which characterized by PARP-1 activation and intracellular NAD+ depletion, was involved in bupivacaine-induced neurotoxicity, and inhibition of PARP-1 attenuated this neuronal injury.