Activation of repair pathways after neuronal DNA damage induced by bupivacaine

AIM To investigate the activation of related repair pathways after bupivacaine-induced neuronal DNA damage by cDNA gene screening. METHODS The bupivacaine-induced SH-SY5Y neuronal damage and DNA damage model was established. The technique of cDNA microplate array was used to screen the 21 important regulatory factors in the DNA damage repair pathway. Post-analysis of these differentially expressed repair genes for the repair pathway enrichment and distribution was performed. The data were analyzed by GraphPad Prism 6 statistical software to compare differences between groups. RESULTS The viability of SH-SY5Y cells treated with bupivacaine at different concentrations （detected by CCK-8 assay） showed that the IC₅₀ value of bupivacaine was 1.5 mmol/L. The comet assay related index （the comet tail） was increased （P<0.05）， the phosphorylation level of γH2AX protein was increased （P<0.05）， indicating that DNA damage in the SH-SY5Y cells was significantly aggravated after bupivacaine treatment. The results of cDNA microplate assay showed that compared withcontrol group， the differentially expressed genes after bupivacaine treatment were DNA-PKcs， PTEN， NTH1， RAD9， CSB， GADD45， XPD， XPC-HR23B and P53. The analysis showed that these repair genes were mainly concentrated in the following 3 repair mechanisms： base excision repair， nucleotide excision repair， and non-homologous reconstitution. CONCLUSION The repair genes differentially expressed after neuronal DNA damage caused by local anesthetics are mainly concentrated in the pathways of non-homologous end-joining， base excision repair and nucleotide excision repair.