The Effect And Mechanism Of HF On Oxidative Damage And Apoptosis In PC12 Cells Induced By Aluminum

Aluminum(Al),an accumulative neurotoxin,caused nervous system dysfunction after excessive intake.Oxidative damage and apoptosis are the main pathogenetic mechanisms of Al neurotoxicity.Our previous experiments showed that HF could significantly reduce the formation of apoptotic bodies on the surface of Al-exposed PC12 cells and decrease the integrity of cell membranes by scanning electron microscopy.Therefore,we propose the hypothesis that HF alleviates aluminum neurotoxicity by inhibiting oxidative stress and apoptosis.In this study,PC12 cells were selected as the study subjects,and PC12 cells were treated with gradient HF for different times.The optimal dose and time of HF intervention experiment were selected through cell activity test,and then the optimal concentration(1 μM)of HF was used.PC12 cells were pretreated for 12 h and 500 μM Al-malt was added for 48 h to establish a PC12 cell model with HF intervention in Al-malt exposure.To investigate the protective effect of HF on Al-malt-induced oxidative damage and apoptosis,PC12 cells were cultured and divided into the control group(C),Al-treatment group(500 μM Al-malt),HF intervention group(500 μM Al-malt+1 μM HF)and HF-treatment group(1 μM HF),the viability of PC12 cells,LDH leakage,cell morphological change,the level of ROS and MDA,the activity of SOD and GSH-Px,MMP,the protein expression of Cyt-c,Caspase-3 activity,as well the mRNA expression of Bcl-2、 Bax and Caspase-3were detected.The results were shown as follows:(1)The survival rate of PC12 cells in the Al-treatment group was significantly lower than that in the C group(p<0.01),and the release of LDH was significantly higher than that in the C group(p<0.01);the survival rate of PC12 cells in the HF intervention group was significantly higher than that in the Al-treatment group(p <0.01),the release of LDH was significantly lower than that of the Al-treatment group(p<0.01);there was no significant difference in the survival rate and LDH leakage of PC12 cells between the HF group and the C group,indicating that HF can alleviate the Al-induced injury of PC12 cells,and HF has no toxicity on PC12 cells.(2)Scanning electron microscopy showed that PC12 cells in the group C and HF grew well,with a star or pyramid shape,and cell connections integrity;PC12 cells in the Al-treatment group became round,cell bodies contracted,cell membrane integrity lost,and cell surface forms apoptotic body;the HF intervention group PC12 cell morphology and intercellular connections returned to normal,and apoptotic bodies reduced,indicating that HF can alleviate the Al-induced morphological changes of PC12 cell.(3)The levels of ROS and MDA in PC12 cells treated with Al-malt were significantly higher than those in the group C(p<0.01),and the activities of SOD and GSH-Px were significantly lower than those in the group C(p<0.01).However,the ROS and MDA levels of PC12 cells in the HF intervention group were significantly lower than those in the aluminum group(p<0.01),and the activities of SOD and GSH-Px were significantly higher than those in the aluminum group(p<0.01),indicating that HF can relieve aluminum-induced oxidative stress.(4)The apoptosis rate,Cyt-c protein expression,Capsase-3 activity,and Bax,Bcl-2,and Caspase-3 mRNA expression were significantly higher in the Al-treatment group than those in the C group(p<0.01).MMP was significantly lower in the group C(p<0.01);the apoptotic rate,Cyt-c protein expression,Capsase-3 activity and Bax,Bcl-2,and Caspase-3 mRNA expression in PC12 cells were significantly lower in the HF intervention group than those in the Al-treatment group(p<0.01),MMP was significantly higher than that of the Al-treatment group(p<0.01),indicating that HF can effectively alleviate Al-induced apoptosis in PC12 cells.The above results showed that HF can effectively alleviate the Al-induced oxidative damage and apoptosis in PC12 cells,which could provide theoretical basis and experimental basis for the Al neurotoxicity.