Basic Research
Copyright ©The Author(s) 2004. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Sep 1, 2004; 10(17): 2514-2518
Published online Sep 1, 2004. doi: 10.3748/wjg.v10.i17.2514
Improvement of barrier function and stimulation of colonic epithelial anion secretion by Menoease Pills
Jin-Xia Zhu, Ning Yang, Gui-Hong Zhang, Lai-Ling Tsang, Yu-Lin Gou, Hau-Yan Connie Wong, Yiu-Wa Chung, Hsiao-Chang Chan
Jin-Xia Zhu, Lai-Ling Tsang, Yu-Lin Gou, Hau-Yan Connie Wong, Yiu-Wa Chung, Hsiao-Chang Chan, Epithelial Cell Biology Research Center, Department of Physiology, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong, China
Jin-Xia Zhu, Ning Yang, Gui-Hong Zhang, Department of Physiology, Medical School, Zhengzhou University, Zhengzhou 450052, Henan Province, China
Author contributions: All authors contributed equally to the work.
Supported by a fund from the Innovation and Technology Commission of Hong Kong, SAR
Correspondence to: Professor Hsiao-Chang Chan, Epithelial Cell Biology Research Center, Department of Physiology, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, China. hsiaocchan@cuhk.edu.hk
Telephone: +852-26096839 Fax: +852-26035022
Received: February 2, 2004
Revised: February 24, 2004
Accepted: March 4, 2004
Published online: September 1, 2004
Abstract

AIM: Menoease Pills (MP), a Chinese medicine-based new formula for postmenopausal women, has been shown to modulate the endocrine and immune systems[1]. The present study investigated the effects of MP and one of its active ingredients, ligustrazine, on epithelial barrier and ion transport function in a human colonic cell line, T84.

METHODS: Colonic transepithelial electrophysiological characteristics and colonic anion secretion were studied using the short circuit current (ISC) technique. RT-PCR was used to examine the expression of cytoplasmic proteins associated with the tight junctions, ZO-1 (zonula occludens-1) and ZO-2 (zonula occludens-2).

RESULTS: Pretreatment of T84 cells with MP (15 μg/mL) for 72 h significantly increased basal potential difference, transepithelial resistance and basal ISC. RT-PCR results showed that the expressions of ZO-1 and ZO-2 were significantly increased after MP treatment, consistent with improved epithelial barrier function. Results of acute stimulation showed that apical addition of MP produced a concentration-dependent (10-5000 μg/mL, EC50 = 293.9 μg/mL) increase in ISC. MP-induced ISC was inhibited by basolateral treatment with bumetanide (100 μmol/L), an inhibitor of the Na + -K + -2Cl- cotransporter, apical addition of Cl- channel blockers, diphenylamine-2, 2’-dicarboxylic acid (1 mmol/L) or glibenclamide (1 mmol/L), but not 4, 4’-diisothiocyanostilbene-2, 2’-disulfonic acid or epithelial Na + channel blocker, amiloride. The effect of MP on ZO-1 and ZO-2 was mimicked by Ligustrazine and the ligustrazine-induced ISC was also blocked by basolateral application of bumetanide and apical addition of diphenylamine-2, 2'-dicarboxylic acid or glibenclamide, and reduced by a removal of extracellular Cl-.

CONCLUSION: The results of the present study suggest that MP and ligustrazine may improve epithelial barrier function and exert a stimulatory effect on colonic anion secretion, indicating the potential use of MP and its active ingredients for improvement of GI tract host defense and alleviation of constipation often seen in the elderly.

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