Omega-3 fatty acids induce Ca2＋ mobilization responses in human colon epithelial cell lines endogenously expressing FFA4  

作　　者：Jung-min KIM Kyoung-pil LEE Soo-jin PARK Saeromi KANG Jin HUANG Jung-min LEE Koichi SATO Hae-young CHUNG Fumikazu OKAJIMA Dong-soon IM 

机构地区：[1]Molecular Inflammation Research Center for Aging Intervention (MRCA) and College of Pharmacy, Pusan National University, Busan 609-735, Republic of Korea [2]Laboratory of Signal Transduction, Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi 371-8512, Japan

出　　处：《Acta Pharmacologica Sinica》2015年第7期813-820,共8页中国药理学报（英文版）

摘　　要：Aim： Free fatty acid receptor 4 （FFA4; formerly known as GPR120） is the G protein-coupled receptor （GPCR） for omega-3 poly- unsaturated fatty acids. FFA4 has been found to express in the small intestines and colons of mice and humans. In this study we investigate the effects of omega-3 polyunsaturated fatty acids on FFA4 in human colon epithelial cells in vitro. Methods： HCT116 and HT-29 human colon epithelial cell lines endogenously expressing FFA4 were used. Intracellular Ca2＋ concentra- tion （[Ca2＋]） was measured in fura 2-AM-loaded cells with fluorescence spectrophotometry. RT-PCR and immunohistochemistry were used to detect FFA4. Results： Ten to 100 pmol/L of omega-3 polyunsaturated fatty acids cx-linolenic acid （at_A） or eicosapentaenoic acid （EPA） induced dose- dependent [Ca2＋] increase in HCT116 and HT-29 cells, whereas docosahexaenoic acid （DHA） had no effect. In addition, the omega-6 fatty acids linoleic acid and y-linoleic acid also dose-dependently increase [Ca2＋], but the mono-unsaturated fatty acid oleic acid and saturated fatty acids such as stearic acid and palmiticacid had no effect. In HCT116 and HT-29 cells, the aLA-induced [Ca2＋] increase was partially inhibited by pretreatment with EGTA, phospholipase C inhibitor edelfosine, cADPR inhibitors 8-bro-cADPR or DAB, and abolished by pretreatment with Ca2＋ATPase inhibitor thapsigargin, but was not affected by Gi/o protein inhibitor PTX or IP3R inhibitor 2-APB. Conclusion： Omega-3 and omega-6 long-chain polyunsaturated fatty acids （C18-20） induce Ca2＋ mobilization responses in human colonic epithelial cells in vitro through activation of FFA4 and PTX-insensitive Gi/o protein, followed by Ca2＋ release from thapsigargin- sensitive Ca2＋ stores and Ca2＋ influx across the plasma membrane.Aim： Free fatty acid receptor 4 （FFA4; formerly known as GPR120） is the G protein-coupled receptor （GPCR） for omega-3 poly- unsaturated fatty acids. FFA4 has been found to express in the small intestines and colons of mice and humans. In this study we investigate the effects of omega-3 polyunsaturated fatty acids on FFA4 in human colon epithelial cells in vitro. Methods： HCT116 and HT-29 human colon epithelial cell lines endogenously expressing FFA4 were used. Intracellular Ca2＋ concentra- tion （[Ca2＋]） was measured in fura 2-AM-loaded cells with fluorescence spectrophotometry. RT-PCR and immunohistochemistry were used to detect FFA4. Results： Ten to 100 pmol/L of omega-3 polyunsaturated fatty acids cx-linolenic acid （at_A） or eicosapentaenoic acid （EPA） induced dose- dependent [Ca2＋] increase in HCT116 and HT-29 cells, whereas docosahexaenoic acid （DHA） had no effect. In addition, the omega-6 fatty acids linoleic acid and y-linoleic acid also dose-dependently increase [Ca2＋], but the mono-unsaturated fatty acid oleic acid and saturated fatty acids such as stearic acid and palmiticacid had no effect. In HCT116 and HT-29 cells, the aLA-induced [Ca2＋] increase was partially inhibited by pretreatment with EGTA, phospholipase C inhibitor edelfosine, cADPR inhibitors 8-bro-cADPR or DAB, and abolished by pretreatment with Ca2＋ATPase inhibitor thapsigargin, but was not affected by Gi/o protein inhibitor PTX or IP3R inhibitor 2-APB. Conclusion： Omega-3 and omega-6 long-chain polyunsaturated fatty acids （C18-20） induce Ca2＋ mobilization responses in human colonic epithelial cells in vitro through activation of FFA4 and PTX-insensitive Gi/o protein, followed by Ca2＋ release from thapsigargin- sensitive Ca2＋ stores and Ca2＋ influx across the plasma membrane.

关 键 词：long-chain fatty acid omega-3 a-linolenic acid FFA4 Ca2＋ mobilization CADPR human colon epithelial cells 

分 类 号：Q939.132[生物学—微生物学] S831.5[农业科学—畜牧学]