title: Caspase-3 is involved in IFN-γ- and TNF-α-mediated MIN6 cells apoptosis via NF-κB/Bcl-2 pathway.
abstract: TNF-α and IFN-γ are the major pro-inflammatory cytokines in the β-cell destruction. However, the underlying mechanism remains unclear. The present study used a murine insulinoma cell line MIN6 for further investigation of the effect of Caspase-3 on the cytokines-induced pancreatic β-cell apoptosis and analyzed the mechanisms involved in the activation of Caspase-3. It was showed that the combination of IFN-γ and TNF-α significantly reduced the viability of MIN6 cells and the observed cells growth inhibition was due to cell apoptosis as judged by the morphological changes under a confocal laser scanning microscopy and FACS assay of Annexin-V/7-AAD double staining. Accompanying with NF-κB activation and Bcl-2 downregulation, both the cleaved Caspase-3 and PARP, a known substrate of Caspase-3 in vivo, were observed at 24 and 12 h, respectively, after cells exposure to IFN-γ and TNF-α treatment. Pretreatment of Caspase-3 inhibitors remarkably attenuated IFN-γ- and TNF-α-induced cells apoptosis. Inhibition of NF-κB activation led to the increase in Bcl-2 expression, a significant attenuation in Caspase-3 activity, and an obvious amelioration in cells viability in IFN-γ- and TNF-α-treated MIN6 cells. Taken together, our results indicate that Caspase-3 is critical for the induction of MIN6 cells apoptosis and it's activation is further confirmed to be related to the NF-κB-mediated Bcl-2 downregulation, which may be the underlying mechanism of IFN-γ- and TNF-α-mediated MIN6 cells apoptosis.
authors.affiliation: School of Pharmacy and Life Sciences, University of South China, Hengyang, 421001, People's Republic of China.
authors.forename: Zhao-hui
authors.initials: ZH
authors.lastname: Cao
authors.forename: Wei-dong
authors.initials: WD
authors.lastname: Yin
authors.forename: Quan-you
authors.initials: QY
authors.lastname: Zheng
authors.forename: Shao-long
authors.initials: SL
authors.lastname: Feng
authors.forename: Gui-lian
authors.initials: GL
authors.lastname: Xu
authors.forename: Ke-qin
authors.initials: KQ
authors.lastname: Zhang
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents; D017209:Apoptosis / Q000187:drug effects* / Q000235:genetics; D053148:Caspase 3 / Q000378:metabolism*; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D015536:Down-Regulation / Q000187:drug effects; D007371:Interferon-gamma / Q000378:metabolism* / Q000494:pharmacology; D051379:Mice; D016328:NF-kappa B / Q000378:metabolism*; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism* / Q000494:pharmacology
chemical_list: D000970:Antineoplastic Agents; D016328:NF-kappa B; D019253:Proto-Oncogene Proteins c-bcl-2; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma; D011065:Poly(ADP-ribose) Polymerases; D053148:Caspase 3