Résumé
Objective To explore the impacts and potential mechanisms of MitoQ on isoflurane-induced injury of primary cultured hippocampal neurons in newborn rats.Methods Fifteen healthy SPF Sprague-Dawley rats of both sex were randomly divided into three groups (n =5 each)u-sing a random number table:control group (group C),multiple exposures to isoflurane anesthesia group (group I)and multiple exposures to isoflurane anesthesia+MitoQ group (group IM).On post-natal days 7,14 and 21,1.5% isoflurane was inhaled for 2 h in group I.MitoQ was intraperitoneally administered in a volume of 0.4 ml/kg before isoflurane anesthesia in group IM,while a mixture of oxygen and air was inhaled instead of isoflurane in group C.HE staining was carried out on postnatal day 28 to observe the morphological changes in hippocampal CA1 region of rat neural cell structures. Hippocampal neuron cells were dissected from clean Sprague-Dawley rats born in 24 h.After primary culture for seven days,MTT assay and TUNEL assay was respectively performed to measure the cell viability and apoptosis of hippocampal neurons.The malondialdehyde (MDA)content and superoxide dismutase (SOD)activity were detected respectively using the thiobarbituric method and xanthinoxi-dase method.Mitochondrial membrane potential (MMP)was measured by rhodamine 123 staining, intracellular levels of reactive oxygen species (ROS)were tested by DCFH-DA staining.Western blot was used to analyze the protein levels of Bax,Bcl-2 and caspase-3.Results Compared with group C, group I decreased the number of neural cells and the cell survival rate;the apoptotic rate was signifi-cantly increased;MDA contents and ROS production were significantly increased;SOD activity and MMP level were significantly decreased;the expression of Bax and caspase-3 were significantly in-creased,while the expression of Bcl-2 was significantly decreased (P < 0.05 ).Compared with the group I,the damaged neural cells were decreased,the cell survival rate was significantly increased, the apoptotic rate was significantly decreased in group IM;MDA contents and ROS production were significantly decreased;SOD activity and MMP level were significantly increased;the expression of Bax and caspase-3 were significantly decreased,while the expression of Bcl-2 was significantly in-creased (P < 0.05 ).Conclusion Antioxidant MitoQ attenuates isoflurane-induced neuron damage, which may be associated with the inhibition on oxidative stress and mitochondrial dysfunction.