Inhibition of nicotine on apoptosis of chondrocytes induced by monosodium iodoacetate / 中国比较医学杂志

ABSTRACT

Objective To explore inhibition of nicotine on apoptosis of chondrocytes induced by monosodium iodoacetate ( MIA) .Methods Rat primary chondrocytes were isolated by enzyme digestion, and the cells were treated with 10 -8 , 10 -7 , 10 -6 , 10 -5 mol/L nicotine for 48 h.The cases were randomly divided into five groups, except for normal group, the other four groups were treated with 4μmol/L MIA 24 h, and three groups were treated 10 -8 , 10 -7 , 10 -6 mol/L nicotine.The viability of chondrocytes was detected by MTT assay.The apoptosis of chondrocytes was examed by Annexin V-FITC/PI flow dual-staining method.The activity of cysteinyl aspartate specific proteinase 3 ( Caspase 3 ) was measured by spectrophotography method.The activation of phosphatidylinositol 3 kinase ( PI3K)/protein kinase B ( AKT) and the expression of down-stream molecule Bax, Bcl-2 was assayed by western blot.Results 10 -7 , 10 -6 mol/L nicotine increased chondrocytes' viability (P0.05).10 -8, 10 -7, 10 -6 mol/L nicotine could increase MIA-induced chondrocytes' viability (P<0.05), suppress MIA-induced chondrocytes' apoptosis and the activity of MIA-induced Caspase 3 (P <0.05).Moreover, 10 -7, 10 -6 mol/L nicotine could increase the expression of PI3K and phosphorylation of AKT ( P<0.05) , down-regulate the expression of Bax and up-regulate the expression of Bcl-2 in MIA-induced rat chondrocytes ( P<0.05 ) .Conclusion These results suggested nicotine could exert anti-apoptosis in MIA-induced rat chondrocytes, which might be related to PI3K/AKT signal pathway.