Scutellarin Intervenes The Toxicity Induced By ?-amyloid Peptide Via ATP-sensitive Potassium Channel In Vitro

Objective:To investigate the effect of scutellarin?Scu?on ATP-sensitive potassium channel(K_ATP)in cell model induced by?-amyloid protein(A?_1-42),and to explore the mechanism of K_ATP against A?toxicity.Methods:SH-SY5Y cells were divided into control group,Scu treatment group,A?treatment group,Scu+A?treatment group,and DZ+A?treatment group.CCK-8 was used to screen the concentration of drugs acting on cells.The content of adenosine triphosphate?ATP?was determined by biochemical method.The expressions of Kir6.1,Kir6.2,SUR1 and SUR2 were examined by western blotting?WB?.Cell membrane potential was detected by using fluorescence probe DiBAC4?3?and mitochondrial membrane potential was examined by using JC-1.Total apoptosis rate of each group was determined by AnnexinV/PI double staining.Results:Compared with the control group,there was no significant change in the Scu treatment group,but the content of ATP?6.84±0.68?was obviously reduced?P<0.05?,the protein expressions of Kir6.1?1.09±0.23?and SUR2?1.02±0.08?were increased?P<0.01?and there were no significant changes in the protein expressions of Kir6.2 and SUR1,cell membrane potential?7.38±0.14?and mitochondrial membrane potential?1.43±0.02?were elevated?P<0.05?,and the apoptotic rate?17.58±0.48?%was increased in the A?treatment cells?P<0.05?.The interventions of Scu could regulate the above indicators tending to normal,where the content of ATP?8.78±0.73?was elevated?P<0.05?,the protein expressions of Kir6.1?0.74±0.12?and SUR2?0.76±0.07?were down-regulated?P<0.01?,cell membrane potential?6.86±0.20?and mitochondrial membrane potential?1.23±0.05?were reduced?P<0.05?,and the apoptotic rate?11.23±0.84?%was decreased?P<0.01?.The changes of all above indicators of the cells treated with DZ+A?were almost the same as the cells treated with Scu+A??P<0.05?.Compared with Scu+A?treatment group,the content of ATP?7.22±0.30?was small?P<0.05?and the apoptotic rate?9.67±1.03?was low?P<0.05?.Conclusion:Scu may regulate ATP-mediated K_ATPTP channel-related Kir6.1/SUR2 subunits to improve cell membrane potential and mitochondrial membrane potential,and increase the opening of the K_ATP channel to inhibit apoptosis induced by A?toxicity,thereby exerting neuroprotective effects.