白杨素通过PI3K/AKT信号通路抑制LPS诱导的软骨细胞自噬

目的探索白杨素对脂多糖诱导的大鼠软骨细胞骨关节炎模型中对软骨细胞自噬的作用及其机制。方法提取10只SPF级SD大鼠关节软骨正常细胞进行体外分离培养,通过LPS诱导大鼠软骨细胞自噬。实验分为空白对照组、LPS组、白杨素(CHR)组和LPS+CHR组;CCK-8法检测各分组细胞的活性、Rhodamine123检测各组细胞中线粒体膜电位、DCFH-DA检测各组细胞的活性氧,Western blot法检测各组细胞中PI3K、AKT、p-PI3K、p-AKT、Beclin-1及LC3Ⅱ的蛋白表达。结果白杨素对LPS诱导的软骨细胞自噬具有抑制作用,且当白杨素浓度为10 mmol·L^-1时抑制自噬作用最为显著;白杨素能够抑制LPS所致LPS诱导的软骨细胞的活性氧(ROS)的增加;白杨素抑制了细胞受损后线粒体膜电位的降低;同时白杨素抑制Beclin-1、LC3Ⅱ蛋白的表达,抑制PI3K和AKT的磷酸化。结论白杨素可能通过抑制PI3K/AKT信号通路,下调自噬蛋白Beclin-1和LC3Ⅱ的表达抑制自噬,进而保护软骨细胞。

Chrysin inhibits LPS-induced autophagy of chondrocytes through PI3K/AKT signaling pathway

Aim To explore the effect of chrysin on chondrocyte autophagy in rat chondrocyte osteoarthritis model induced by lipopolysaccharide and its mechanism.Methods Normal articular cartilage cells of 10 SPF SD rats were isolated and cultured in vitro,and the autophagy of rat chondrocytes was induced by LPS.The experiment was divided into blank control group,LPS group,chrysin(CHR)group and LPS+CHR group,the activity of cells in each group was detected by CCK-8 method,the mitochondrial membrane potential of cells in each group was detected by Rhodamine123,and the protein expression of PI3K,AKT,p-PI3K,p-AKT,Beclin-1 and LC3Ⅱin cells of each group was detected by reactive oxygen species,Western blot method of DCFH-DA.Results Chrysin could inhibit the autophagy induced by LPS,especially when the concentration of chrysin was 10 mmol·L^-1.Chrysin could inhibit the increase of reactive oxygen species(ROS)induced by LPS induced by LPS,inhibit the decrease of mitochondrial membrane potential after injury,and inhibit the expression of Beclin-1 and LC3Ⅱprotein and the phosphorylation of PI3K and AKT.Conclusions Chrysin may inhibit autophagy by inhibiting PI3K/AKT signaling pathway and down-regulating the expression of autophagy proteins Beclin-1 and LC3Ⅱ,thus protecting chondrocytes.