原花青素对IL-1β诱导的软骨细胞凋亡的影响及其机制

Effect and underlying mechanism of procyanidin on IL-1β-induced apoptosis of chondrocytes

目的探讨原花青素对IL-1β诱导的软骨细胞凋亡的影响及其可能机制。方法分别用原花青素0、10、20、40、60、100μmol/L干预软骨细胞48 h,采用CCK-8法检测原花青素对软骨细胞活性的影响。将软骨细胞分为IL-1β处理组(A组)、IL-1β+原花青素处理组(B组)和空白对照组(C组),采用RT-PCR和Western blot法分别检测软骨细胞中磷脂酰肌醇3-激酶(PI3K)、Akt、Bcl-2、Bax和Caspase-3 mRNA和蛋白表达,Hoechst/碘化丙啶染色检测软骨细胞凋亡,并观察乳酸脱氢酶(LDH)释放情况。结果原花青素浓度为40μmol/L时,软骨细胞活性达峰值(P<0.01)。与C组相比,A组软骨细胞LDH释放量、细胞凋亡以及Bax、Caspase-3 mRNA和蛋白表达均增加(P<0.01),PI3K、Akt和Bcl-2 mRNA和蛋白表达降低(P<0.01);而B组加入原花青素处理后能逆转上述各指标的变化过程(P<0.05或P<0.01)。结论原花青素可以抑制IL-1β诱导的软骨细胞凋亡;其保护机制可能与激活PI3K/Akt通路、上调Bcl-2以及下调Bax和Caspase-3的表达有关。

Objective To investigate the effect and underlying mechanism of procyanidin on IL-1β-induced apoptosis of chondrocytes.Methods The chondrocytes were treated with different concentrations of procyanidin 0,10,20,40,60 and 100 μmol/L for 48 hours and the viability of chondrocytes was measured by CCK-8 method.The chondrocytes then were divided into three groups of A(treated with IL-1β),B(treated with IL-1β and procyanidin) and C(blank control).The mRNA and protein expressions of PI3 K,Akt, Bcl-2,Bax and Caspase-3 were detected by RT-PCR and Western blot, respectively.The cell apoptosis was analyzed by Hoechst/propidium iodide staining method, and the release of lactate dehydrogenase(LDH) was observed.Results The viability of chondrocytes reached the peak at the concentration of procyanidin 40 μmol/L(P<0.01).Compared with group C,the release of LDH,cell apoptosis and mRNA and protein expressions of Bax and Caspase-3 were significantly increased(P<0.01),while the mRNA and protein expressions of PI3 K,Akt and Bcl-2 were decreased in group A(P<0.01),which were all reversed after the treatment of procyanidin in group B(P<0.05 or P<0.01).Conclusion Procyanidin could inhibit the apoptosis of chondrocytes induced by IL-1β,which may be related to the activation of PI3 K/Akt pathway, upregulation of Bcl-2 expression and downregulation of Bax and Caspase-3 expressions.