中文摘要：

目的研究烟酰胺对白介素-1β（IL-1β）诱导HEK-293细胞凋亡的保护作用及机制。方法体外培养HEK-293细胞,将HEK-293细胞分成6组,在培养基内加不同浓度的IL-1β、烟酰胺干预。干预3 d后噻唑蓝（MTT）检测、Annexin V-PI染色、caspase-3、8、9活性检测、细胞内活性氧簇（ROS）水平、ATP浓度及线粒体膜电位检测。结果应用烟酰胺的MTT吸光度明显升高,凋亡细胞比例明显降低,caspase-3、8、9活力降低,ATP浓度明显增加,ROS水平明显减少;线粒体膜电位红绿荧光比值明显增加。结论体外条件下,烟酰胺促进HEK-293细胞的增殖并抑制IL-1β诱导的HEK-293细胞凋亡,其对细胞凋亡的保护作用可能主要通过保护线粒体功能从而改善细胞线粒体能量代谢来实现。

英文摘要：

OBJECTIVE To investigate protective effects and mechanisms of niacinamide on HEK-293 cell apoptosis induced by IL-1β in vitro.METHODS Cultured HEK-293 cells were divided into 6 groups,and various concentrations of IL-1β and niacinamide were added to the mediums for intervention.After 3 d of intervention,cell proliferation activity,Annexin V-PI staining,intracellular caspase-3,8 and 9 activity,intracellular ATP concentration,intracellular reactive oxygen species level and mitochondrial membrane potential were detected respectively.RESULTS The MTT absorbance were increased significantly,the apoptotic ratios were descended,the caspase-3,8 and 9 activities were all decreased,the ATP concentrations were increased higher significantly in groups intervented with niacinamide compared with group 3 but the reactive oxygen species levels in groups intervented with niacinamide were decreased compared with group 3 significantly,while the red/green fluorescence intensity ratios in groups intervented with niacinamide were increased obviously compared with group 3 in mitochondrial membrane potential assay.CONCLUSION Niacinamide can promote HEK-293 cells proliferation and inhibit HEK-293 cells apoptosis induced by IL-1β in vitro.The protective effects of niacinamide against cell apoptosis mainly acts via protection of the mitochondrial function to improve cellular mitochondrial energy metabolism.