【摘要】 目的:从天然单体化合物中筛选能够激活囊性纤维化跨膜电导调节因子(CFTR)Cl-通道转运活性的激活剂。方法:利用稳定表达人CFTR和对卤族元素碘离子高度敏感的荧光绿蛋白突变体EYFP-H148Q的Fischer大鼠甲状腺上皮细胞为筛选模型,测定386种中药单体化合物对CFTR介导的I-内流速度的影响。结果:发现生物碱类化合物荷叶碱对野生型和△F508突变型CFTRCl-通道具有激活作用,而对G551D突变型CFTRCl-通道无激活作用。荷叶碱对野生型和△F508突变型CFTRCl-通道的激活作用具有作用迅速、可逆的特点,并且依赖于细胞内cAMP水平。荷叶碱不提高细胞内cAMP水平,当CFTR磷酸化程度达到最大时仍能进一步激活CFTRCl-通道激活作用,表明它可能是通过与CFTR直接结合而发挥作用的。结论:首次发现荷叶碱对野生型和△F508突变型CFTRCl-通道的激活作用,该天然化合物将在阐明CFR活性机制及作为先导化合物开发与CFTR有关的疾病治疗药物等方面具有重要用途。更多还原

【Abstract】 AIM:To identify CFTR Cl-channel gating potentiators from natural compounds.METHODS:A stably transfected Fischer thyroid epithelial(FRT)cell line co-expressing human CFTR and a green fluorescent protein mutant with ultra-high halide sensitivity(YFP-H148Q)was used to measure CFTR-mediated iodide influx rate stimulated by the 386 natural compounds.RESULTS:Nuciferine was identified as an effective activator of wild-type CFTR chloride channel by screening of 386 single compounds from Chinese medicinal herbs.The CFTR-stimulating activity is rapid and reversible.Nuciferine does not elevate cellular cAMP level and activates phophorylated CFTR,suggesting that it works by direct binding to CFTR molecule.Nuciferine can also potentiate the Cl-transport of △F508 mutant CFTR.CONCLUSION:Nuciferine was identified as an effective CFTR chloride channel activator.Nuciferine may be useful for probing CFTR channel gating mechanisms and as a lead compound to develop pharmacological therapy of CFTR-related disease such as cystic fibrosis,idiopathic chronic pancreatiti,keratoconjunctivitis sicca and habitual constipation.更多还原