Gurgul-Convey Ewa, Mehmeti Ilir, Plötz Thomas, Jörns Anne, Lenzen Sigurd
Institute of Clinical Biochemistry, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.
Institute of Experimental Diabetes Research, Hannover Medical School, Hannover, Germany.
Diabetologia. 2016 Oct;59(10):2125-33. doi: 10.1007/s00125-016-4060-y. Epub 2016 Jul 27.
AIMS/HYPOTHESIS: The aim of this study was to perform a detailed analysis of cytokine toxicity in the new human EndoC-βH1 beta cell line.
The expression profile of the antioxidative enzymes in the new human EndoC-βH1 beta cells was characterised and compared with that of primary beta cells in the human pancreas. The effects of proinflammatory cytokines on reactive oxygen species formation, insulin secretory responsiveness and apoptosis of EndoC-βH1 beta cells were determined.
EndoC-βH1 beta cells were sensitive to the toxic action of proinflammatory cytokines. Glucose-dependent stimulation of insulin secretion and an increase in the ATP/ADP ratio was abolished by proinflammatory cytokines without induction of IL-1β expression. Cytokine-mediated caspase-3 activation was accompanied by reactive oxygen species formation and developed more slowly than in rodent beta cells. Cytokines transiently increased the expression of unfolded protein response genes, without inducing endoplasmic reticulum stress-marker genes. Cytokine-mediated NFκB activation was too weak to induce inducible nitric oxide synthase expression. The resultant lack of nitric oxide generation in EndoC-βH1 cells, in contrast to rodent beta cells, makes these cells dependent on exogenously generated nitric oxide, which is released from infiltrating immune cells in human type 1 diabetes, for full expression of proinflammatory cytokine toxicity.
CONCLUSIONS/INTERPRETATION: EndoC-βH1 beta cells are characterised by an imbalance between H2O2-generating and -inactivating enzymes, and react to cytokine exposure in a similar manner to primary human beta cells. They are a suitable beta cell surrogate for cytokine-toxicity studies.
目的/假设：本研究的目的是对新的人EndoC-βH1β细胞系中的细胞因子毒性进行详细分析。
对新的人EndoC-βH1β细胞中抗氧化酶的表达谱进行了表征，并与人类胰腺中的原代β细胞进行了比较。测定了促炎细胞因子对EndoC-βH1β细胞活性氧生成、胰岛素分泌反应性和凋亡的影响。
EndoC-βH1β细胞对促炎细胞因子的毒性作用敏感。促炎细胞因子消除了葡萄糖依赖性的胰岛素分泌刺激和ATP/ADP比值的增加，且未诱导IL-1β表达。细胞因子介导的半胱天冬酶-3激活伴随着活性氧的形成，且比啮齿动物β细胞中的发展更为缓慢。细胞因子短暂增加了未折叠蛋白反应基因的表达，而未诱导内质网应激标记基因。细胞因子介导的NFκB激活太弱，无法诱导诱导型一氧化氮合酶表达。与啮齿动物β细胞相反，EndoC-βH1细胞中一氧化氮生成的缺乏使得这些细胞依赖于外源性生成的一氧化氮（其由人类1型糖尿病中浸润的免疫细胞释放）来充分表达促炎细胞因子毒性。
结论/解读：EndoC-βH1β细胞的特征在于产生H2O2和使H2O2失活的酶之间的失衡，并且对细胞因子暴露的反应方式与原代人β细胞相似。它们是用于细胞因子毒性研究的合适的β细胞替代物。
