QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: mol.105.020578v1 69/4/1405    most recent Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Kim, H. Articles by Jung, Y. Search for Related Content PubMed PubMed Citation Articles by Kim, H. Articles by Jung, Y.

A Molecular Mechanism for the Anti-Inflammatory Effect of Taurine-Conjugated 5-Aminosalicylic Acid in Inflamed Colon

Laboratory of Biomedicinal Chemistry (He.K., H.J., Y.J.)/Medicinal Chemistry (Y.Y., B.C., Y.M.K.), College of Pharmacy, Pusan National University, Busan, Korea; and Urologic Oncology Branch, National Cancer Institute, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (Hy.K., L.N.)

In previous reports, a novel colon-specific prodrug, 5-aminosalicyltaurine (5-ASA-Tau) administered orally, is successfully delivered to and liberates 5-aminosalicylic acid (5-ASA) and taurine in the inflamed large intestine of rats. Furthermore, the prodrug ameliorates the 2,4,6-trinitrobenzene-sulfonic acid-induced colitis, and taurine acts not only as a carrier but also as an active therapeutic agent. In this study, we investigated the anti-inflammatory properties of the prodrug at a molecular level. After rectal administration of taurine, formation of taurine chloramine (TauCl) in the inflamed colonic tissue was examined using high-performance liquid chromatography. In human colon epithelial cell lines, nuclear factor-B (NF-B) activity was accessed using an NF-B-dependent luciferase reporter gene. Protein levels were monitored by Western blotting. DNA binding activity of the NF-B subunit p65 was determined using a DNA binding assay kit. A millimolar level of TauCl was formed in the inflamed tissue. TauCl inhibited tumor necrosis factor (TNF)-dependent NF-B activation by modifying thiol(s) on p65 and blocking DNA binding. In addition, 5-ASA inhibited phosphorylation of p65 at serine 536, which is critical for transcriptional activity of NF-B. Furthermore, combined TauCl/5-ASA treatment additively inhibited TNF-dependent NF-B activation. Together, our data suggest that the colon-specific carrier taurine contributes to the clinical effect of the prodrug by potentiating the inhibitory effect of the active ingredient 5-ASA on a major proinflammatory signal, TNF-dependent NF-B activation in the inflamed large intestine.

Received for publication November 4, 2005.

Accepted for publication January 3, 2006.

Address correspondence to: Dr. Yunjin Jung, Laboratory of Biomedicinal Chemistry, College of Pharmacy, Pusan National University, Busan, Korea 609-735. E-mail: jungy{at}pusan.ac.kr