B3型柯萨奇病毒上调NF-κB引起胰岛β细胞凋亡的作用及机制研究

Coxsackievirus B3-induced Apoptosis of Pancreatic-islet β-Cells by Upregulation of NF-κB Expression

B3型柯萨奇病毒(Coxsackie virus B3,CVB3)与1型糖尿病发病、胰岛功能破坏有关,但CVB3对胰岛β细胞凋亡的影响及机制尚不清楚。本研究的目的是观察CVB3上调NF-κB p-p65引起胰岛β细胞凋亡的作用及机制,进而初步探究CVB3感染引起胰岛β细胞损伤的分子机制。本研究培养了人胰岛β细胞株,分为对照组、CVB3组、阴性对照(NC)质粒组、NF-κB p65质粒组、si-NC组、si-NC+CVB3组、si-NF-κB p65+CVB3组,检测细胞活力A490水平、细胞凋亡率及细胞中cleaved caspase-3、NF-κB p-p65、IκBα的表达水平。结果显示与对照组比较,CVB3组的A490水平及细胞中IκBα的表达水平降低,细胞凋亡率及细胞中cleaved caspase-3、NF-κB p-p65的表达水平增加(P<0.05);与NC质粒组比较,NF-κB p65质粒组的A490水平降低,细胞凋亡率及细胞中cleaved caspase-3、NF-κB p-p65的表达水平增加(P<0.05);与si-NC+CVB3组比较,si-NF-κB p65+CVB3组的A490水平增加,细胞凋亡率及细胞中cleaved caspase-3、NF-κB p-p65的表达水平降低(P<0.05)。以上结果表明CVB3感染能够促进胰岛β细胞凋亡,这一促凋亡作用与上调NF-κB有关。本文的创新在于探讨了NF-κB参与CVB3感染引起胰岛β细胞凋亡的过程,表明CVB3感染通过上调NF-κB引起胰岛β细胞凋亡,进而参与1型糖尿病的发病。

Coxsackievirus B3(CVB3)is associated with the onset of type-1 diabetes mellitus and dysfunction of pancreatic islets.Studies focusing on viral myocarditis have shown that CVB3 induces cardiomyocyte apoptosis by upregulating expression of nuclear factor-kappa B(NF-κB)p-p65,but the effect and mechanism of action of CVB3 on pancreatic-isletβ-cell(PIβC)apoptosis are not known.We observed the effect and mechanism of CVB3-induced PIβC apoptosis by upregulating NF-κB expression,and explored the molecular mechanism of CVB3-induced PIβC injury.A human PIβC line was cultured.Cells were divided into seven groups:control,CVB3,NC plasmid,NF-κB p65 plasmid,si-NC,si-NC+CVB3,and si-NF-κB p65+CVB3.Compared with the control group,the absorbance at 490nm(A490)and IκBαexpression in cells decreased,and percent apoptosis as well as expression of cleaved caspase-3 and NF-κB p-p65 in cells increased in the CVB3 group(P<0.05).Compared with the NC plasmid group,A490decreased,and percent apoptosis as well as expression of cleaved caspase-3 and NF-κB p-p65 in cells increased in the NF-κB p65 plasmid group(P<0.05).Compared with the si-NC+CVB3 group,A490increased,and percent apoptosis as well as expression of cleaved caspase-3 and NF-κB p-p65 in cells decreased in the si-NF-κB p65+CVB3 group(P<0.05).These results suggested that CVB3infection could promote PIβC apoptosis,which was related to upregulation of NF-κB expression and contributed to the pathogenesis of type-1 diabetes mellitus.