Phosphorylation and subcellular localization of Na+/H+ exchanger isoform 3 (NHE3) are associated with altered gallbladder absorptive function after formation of cholesterol gallstones
Phosphorylation and subcellular localization of Na+/H+ exchanger isoform 3 (NHE3) are associated with altered gallbladder absorptive function after formation of cholesterol gallstones
复制标题
Na /H 交换异构体 3 (NHE3) 的磷酸化和亚细胞定位与胆固醇胆结石形成后胆囊吸收功能的改变有关
DOI：
10.1007/s13105-016-0533-1
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发表时间：
2017-02-01
影响因子：
3.4
通讯作者：
Kong, Jing
中科院分区：
文献类型：
--
作者：
Chen, Yongsheng;Wu, Shuodong;Kong, Jing
Na+/H+交换器亚型3（NHE 3）功能障碍被认为是导致胆固醇结石疾病中发生的胆囊吸收改变的原因，但其机制尚不清楚。目前的研究进行检查的表达，磷酸化和NHE 3在胆囊上皮细胞（GBECs）的雄性C57 BL/6小鼠在控制或致石饮食的亚细胞定位。将36只8周龄雄性C57 BL/6小鼠随机分配接受高胆固醇饮食或常规饮食8周。记录胆结石形成。检查胆囊胆汁胆固醇、磷脂和总胆汁酸。RT-PCR检测NHE 3 mRNA表达。Western blotting和免疫荧光显微镜分别检测NHE 3蛋白的表达和亚细胞定位。所有喂食致石饮食的小鼠均形成胆结石。尽管结石饮食组小鼠胆囊中NHE 3 mRNA表达高于对照饮食组，但总NHE 3蛋白表达无显著差异。然而，较高水平的丝氨酸-552磷酸化的NHE 3（P-NHE 3）被认为是在致石饮食。免疫荧光结果显示，NHE 3蛋白在小鼠GBEC的顶膜和胞浆均有表达。NHE 3的这种亚细胞分布模式有力地证实了小鼠GBEC中NHE 3活性调节的交换剂运输机制。我们的结论是，增加磷酸化的NHE 3胆结石形成后，导致营业额的交换器，导致胆囊浓缩功能下降。
Na+/H+exchanger isoform 3 (NHE3) dysfunction is thought to contribute to the altered gallbladder absorption that occurs in cholesterol gallstone disease, but the mechanism is unknown. The current study was undertaken to examine the expression, phosphorylation, and subcellular localization of NHE3in gallbladder epithelium cells (GBECs) of male C57BL/6 mice on a control or lithogenic diet. Thirty-six 8-week-old male C57BL/6 mice were randomly assigned to receive a high cholesterol diet or a regular diet for 8 weeks. Gallstone formation was recorded. Gallbladder bile cholesterol, phospholipid, and total bile acids were examined. RT-PCR was used to measure NHE3mRNA expression. NHE3protein expression and subcellular localization were examined by Western blotting and immunofluorescence microscopy, respectively. Gallstones were formed in all mice fed the lithogenic diet. Despite higher NHE3mRNA expression in gallbladders of the mice on the lithogenic diet than in those on the control diet, there was no significant difference in expression of total NHE3protein. However, a higher level of NHE3phosphorylated at serine-552 (P-NHE3) was seen on the lithogenic diet. In immunofluorescence studies, NHE3protein was expressed both on the apical membrane and in the cytoplasm of mouse GBEC. This pattern of subcellular distribution of NHE3strongly corroborates an exchanger trafficking mechanism in NHE3activity regulation in mouse GBEC. We conclude that increased phosphorylation of NHE3following gallstone formation leads to turnover of the exchanger, resulting in decreased gallbladder concentrating function.