Synthesis of oxymatrine hydrazone and its preventive action against sevoflurane induced neuron damage through ERK pathway up-regulation.

Exposure of patients undergoing multiple surgeries to anesthetic compounds leads to harmful side effects such as memory loss and impaired cognition. The current study was aimed to synthesize and investigate the effect of oxymatrine hydrazone on neuronal toxicity induced by sevoflurane in rats. Incubation with oxymatrine hydrazone was followed by exposure to sevoflurane for 48 h and determination of proliferation by 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay. Apoptosis was detected by flow cytometry using Annexin V‑FITC and propydium iodide staining. Western blot analysis was used for determination of changes in protein expression. Sevoflurane exposure significantly (P<0.05) reduced proliferation of neurons by activation of cell apoptosis. However, pretreatment of neurons with oxymatrine hydrazone prevented reduction of proliferative potential induced on exposure with sevoflurane. Pre-treatment of neurons with 5.0 µM doses of oxymatrine hydrazone significantly prevented apoptosis induction by sevoflurane. Moreover, oxymatrine hydrazone pretreatment inhibited BCL2 Associated-X (BAX) and cleaved caspase-3 levels induced by sevoflurane exposure in neurons. Phosphorylation of extracellular signal‑regulated protein kinase (ERK1/2) and expression of BCL-2 in neurons exposed to sevoflurane were markedly promoted on pretreatment with oxymatrine hydrazone. Additionally, U0126 (ERK ½ activation inhibitor) treatment of sevoflurane exposed neurons inhibited promotion of ERK1/2 phosphorylation by oxymatrine hydrazone pre-treatment. In summary, cytotoxicity of sevoflurane in neurons was prevented on pretreatment with oxymatrine hydrazone. Pretreatment of sevoflurane exposed neurons with oxymatrine hydrazone inhibited apoptosis, suppressed BAX/caspase-3 and elevated BCL-2. Moreover, oxymatrine hydrazone pre-treatment promoted ERK1/2 phosphorylation in sevoflurane exposed neurons. Therefore, oxymatrine hydrazone has a great potential for prevention of neurotoxicity induced by sevoflurane.