ABSTRACT
OBJECTIVE To investigate whether quinolinic acid(QA)induces autophagy in PC12 cells and its relationship with glycogen synthase kinase-3β(GSK-3β)/β-catenin related signaling path?ways. METHODS PC12 cells were treated with QA 2.5,5.0 and 10.0 mmol·L-1 for 24 h. The cell viability was determined by MTT assay. Autophagy fluorescent spots labelled form of microtubule-associated protein 1 light chain 3(LC3)was examined by LC3 immunostaining. The expressions of GSK-3β,β-catenin,LC3 and Beclin 1 were determined by Western blotting. RESULTS QA inhibited PC12 cell survival in a concentration-dependent manner,and IC50 was 8.7 mmol · L- 1. Compared with normal control group,QA 2.5,5.0 and 10.0 mmol · L-1 increased autophagic intracellular LC3 fluorescence spots,elevated the expression ratio of LC3-Ⅱ/LC3-Ⅰ and expression of Beclin 1 in PC12 cells(P<0.05). In addition,QA enhanced GSK-3βexpression and decreasedβ-catenin expression(P<0.05,P<0.01). CONCLUSION QA induces autophagy in PC12 cells. This mechanism may be associated with the activation of GSK-3β/β-catenin related signaling pathways.
ABSTRACT
Aim To investigate the expression and im-plication of HIF-1α, ROCK-2 , FoxM1 in PC12 cell in-jury induced by lead acetate. Methods PC12 cells were treated with lead acetate at the doses of 100 , 200 and 400 μmol·L-1 . The cell viability was determined by MTT reduction assay and LDH assay, the intracellu-lar production of oxygen species was measured by as-sessing SOD and MDA levels, cell apoptosis was deter-mined by Hoechst 33342 staining, the expressions of HIF-1α, ROCK-2 , FoxM1 , Bcl-2 and Bax were deter-mined by immunoblotting analysis. Results Lead ac-etate induced cell injury in PC12 cells in a dose-de-pendent manner, and it potentiated oxygen radical pro-duction and cell apoptosis. In addition, lead acetate enhanced HIF-1α and ROCK-2 expressions, increased Bax/Bcl-2 ratio and decreased FoxM1 expression. Conclusion Lead acetate can induce PC12 cell apop-tosis, which may be related with the expressions of HIF-1α, ROCK-2 and FoxM1 . Cellular oxidative stress may contribute to the injury as well.
ABSTRACT
Aim To investigate the role of HIF-1 αin PC1 2 cell injury induced by quinolinic acid.Methods PC1 2 cells were treated with quinolinic acid at the do-ses of 2.5,5 and 1 0 mmol·L -1 ,the cell viability was determined by MTT reduction assay and LDH as-say,the intracellular levels of oxygen species was measured by assessing SOD and MDA levels,cell ap-optosis was determined by Hoechst 33258 staining,the intracellular distribution of HIF-1 αwas examined by HIF-1 αimmunostaining,and the expressions of HIF-1 α,Akt,p-Akt,Bcl-2 and Bax were determined by im-munoblotting analysis.Results Quinolinic acid in-duced cell injury in PC1 2 cells in a dose-dependent manner,and potentiated oxygen radical production and cell apoptosis.In addition,quinolinic acid enhanced HIF-1 αexpression and accumulation in nuclei.The p-Akt expression and Bax/Bcl-2 ratio was increased by quinolinc acid in PC1 2 cells.Conclusions HIF-1 αand Akt mediate qunolinc acid-induced cell apoptosis in PC1 2 cells.And cellular oxidative stress may con-tribute to the injury as well.