Ma Tonghui, Thiagarajah Jay R, Yang Hong, Sonawane Nitin D, Folli Chiara, Galietta Luis J V, Verkman A S
Department of Medicine, Cardiovascular Research Institute, University of California, San Francisco, San Francisco, California 94143-0521, USA.
J Clin Invest. 2002 Dec;110(11):1651-8. doi: 10.1172/JCI16112.
Secretory diarrhea is the leading cause of infant death in developing countries and a major cause of morbidity in adults. The cystic fibrosis transmembrane conductance regulator (CFTR) protein is required for fluid secretion in the intestine and airways and, when defective, causes the lethal genetic disease cystic fibrosis. We screened 50,000 chemically diverse compounds for inhibition of cAMP/flavone-stimulated Cl(-) transport in epithelial cells expressing CFTR. Six CFTR inhibitors of the 2-thioxo-4-thiazolidinone chemical class were identified. The most potent compound discovered by screening of structural analogs, CFTR(inh)-172, reversibly inhibited CFTR short-circuit current in less than 2 minutes in a voltage-independent manner with K(I) approximately 300 nM. CFTR(inh)-172 was nontoxic at high concentrations in cell culture and mouse models. At concentrations fully inhibiting CFTR, CFTR(inh)-172 did not prevent elevation of cellular cAMP or inhibit non-CFTR Cl(-) channels, multidrug resistance protein-1 (MDR-1), ATP-sensitive K(+) channels, or a series of other transporters. A single intraperitoneal injection of CFTR(inh)-172 (250 micro g/kg) in mice reduced by more than 90% cholera toxin-induced fluid secretion in the small intestine over 6 hours. Thiazolidinone CFTR inhibitors may be useful in developing large-animal models of cystic fibrosis and in reducing intestinal fluid loss in cholera and other secretory diarrheas.
分泌性腹泻是发展中国家婴儿死亡的主要原因，也是成人发病的主要原因。囊性纤维化跨膜传导调节因子（CFTR）蛋白是肠道和气道液体分泌所必需的，当该蛋白有缺陷时，会导致致命的遗传性疾病囊性纤维化。我们筛选了50000种化学结构各异的化合物，以寻找能抑制表达CFTR的上皮细胞中cAMP/黄酮刺激的Cl⁻转运的物质。我们鉴定出了6种2-硫代-4-噻唑烷酮化学类别的CFTR抑制剂。通过筛选结构类似物发现的最有效化合物CFTR(inh)-172，能在不到2分钟的时间内以电压非依赖性方式可逆地抑制CFTR短路电流，其抑制常数（K(I)）约为300 nM。在细胞培养和小鼠模型中，高浓度的CFTR(inh)-172无毒。在完全抑制CFTR的浓度下，CFTR(inh)-172不会阻止细胞内cAMP升高，也不会抑制非CFTR Cl⁻通道、多药耐药蛋白-1（MDR-1）、ATP敏感性钾通道或一系列其他转运蛋白。给小鼠腹腔注射一次CFTR(inh)-172（250 μg/kg），可使霍乱毒素诱导的小肠液体分泌在6小时内减少90%以上。噻唑烷酮类CFTR抑制剂可能有助于建立大型囊性纤维化动物模型，并减少霍乱和其他分泌性腹泻中的肠道液体流失。
