Song Yuanlin, Sonawane N D, Salinas Danieli, Qian Liman, Pedemonte Nicoletta, Galietta Luis J V, Verkman A S
Department of Medicine and Physiology, Cardiovascular Research Institute, University of California, San Francisco, California 94143, USA.
J Biol Chem. 2004 Sep 24;279(39):40629-33. doi: 10.1074/jbc.M407308200. Epub 2004 Jul 26.
Curcumin, the yellow colored component of the spice turmeric, has been reported to rescue defective DeltaF508-cystic fibrosis transmembrane conductance regulator (CFTR) cellular processing in homozygous mutant mice, restoring nasal potential differences and improving survival (Egan, M. E., Pearson, M., Weiner, S. A., Rajendran, V., Rubin, D., Glockner-Pagel, J., Canny, S., Du, K., Lukacs, G. L., and Caplan, M. J. (2004) Science 304, 600-602). Because of the implied potential use of curcumin or similar compounds in the therapy of cystic fibrosis caused by the DeltaF508 mutation, we tried to reproduce and extend the pre-clinical data of Egan et al. Fluorometric measurements of iodide influx in Fischer rat thyroid cells expressing DeltaF508-CFTR showed no effect of curcumin (1-40 microm) when added for up to 24 h prior to assay in cells grown at 37 degrees C. Controls, including 27 degrees C rescue and 4 mm phenylbutyrate at 37 degrees C, were strongly positive. Also, curcumin did not increase short circuit current in primary cultures of a human airway epithelium homozygous for DeltaF508-CFTR with a 27 degrees C rescue-positive control. Nasal potential differences in mice were measured in response to topical perfusion with serial solutions containing amiloride, low Cl-, and forskolin. Robust low Cl- and forskolin-induced hyperpolarization of 22 +/- 3 mV was found in wild type mice, with 2.1 +/- 0.4 mV hyperpolarization in DeltaF508 homozygous mutant mice. No significant increase in Cl-/forskolin hyperpolarization was seen in any of the 22 DeltaF508 mice studied using different curcumin preparations and administration regimens, including that used by Egan et al. Assay of serum curcumin by ethyl acetate extraction followed by liquid chromatography/mass spectrometry indicated a maximum serum concentration of 60 nm, well below that of 5-15 microm, where cellular effects by sarcoplasmic/endoplasmic reticulum calcium pump inhibition are proposed to occur. Our results do not support further evaluation of curcumin for cystic fibrosis therapy.
姜黄素是姜黄香料中的黄色成分，据报道，它能挽救纯合突变小鼠中缺陷型ΔF508 - 囊性纤维化跨膜传导调节因子（CFTR）的细胞加工过程，恢复鼻电位差并提高存活率（伊根，M. E.，皮尔逊，M.，韦纳，S. A.，拉金德兰，V.，鲁宾，D.，格洛克纳 - 帕格尔，J.，坎尼，S.，杜，K.，卢卡奇，G. L.，以及卡普兰，M. J.（2004年）《科学》304卷，600 - 602页）。由于姜黄素或类似化合物在治疗由ΔF508突变引起的囊性纤维化方面可能具有潜在用途，我们试图重现并扩展伊根等人的临床前数据。在37℃培养的细胞中，在测定前长达24小时添加姜黄素（1 - 40微摩尔）后，对表达ΔF508 - CFTR的费希尔大鼠甲状腺细胞中的碘流入进行荧光测量，结果显示姜黄素无作用。包括27℃挽救以及37℃下4毫摩尔苯丁酸盐在内 的对照均呈强阳性。此外，在以27℃挽救为阳性对照的、纯合ΔF508 - CFTR的人气道上皮原代培养物中，姜黄素并未增加短路电流。通过向小鼠鼻腔局部灌注含阿米洛利、低氯溶液和福斯可林的系列溶液来测量鼻电位差。在野生型小鼠中发现，低氯溶液和福斯可林诱导的强大超极化幅度为22±3毫伏，在ΔF508纯合突变小鼠中为2.1±0.4毫伏。在使用不同姜黄素制剂和给药方案（包括伊根等人使用的方案）研究的22只ΔF508小鼠中，未观察到氯/福斯可林超极化有显著增加。通过乙酸乙酯萃取然后进行液相色谱/质谱分析血清姜黄素，结果表明血清最大浓度为60纳米，远低于5 - 15微摩尔，据推测，在该浓度下会通过抑制肌浆网/内质网钙泵产生细胞效应。我们的结果不支持对姜黄素用于囊性纤维化治疗进行进一步评估。
