Regulation of the human taurine transporter by TNF-alpha and an anti-inflammatory function of taurine in human intestinal Caco-2 cells.
We investigated whether or not the inflammatory cytokines affect the activity of taurine transporter (TAUT) in human intestinal Caco-2 cells. Among the cytokines, tumor necrosis factor alpha(TNF-alpha) markedly augmented the TAUT activity. A kinetic analysis of the TAUT activity in TNF-alpha-treated Caco-2 cells suggests that this up-regulation was associated with both an increase in the amount of TAUT and an increase in its affinity. Considering these results, it seems that intracellular taurine plays a role in the intestinal epithelial cells under such an inflammatory condition as that caused by an excessive amount of TNF-alpha secreted by macrophages. To verify this hypothesis, we examined the effect of taurine on inflamed intestinal cells by using a co-culture system of Caco-2 cells with human macrophage-like THP-1 cells. The result shows that taurine significantly repressed the damage to Caco-2 cells caused by TNF-alpha secreted by THP-1 cells. Thus, taurine may be a useful substance against intestinal inflammation.
Mochizuki
Tetsunosuke
T
Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan. aa37021@mail.ecc.u-tokyo.ac.jp
Satsu
Hideo
H
Nakano
Tomoko
T
Shimizu
Makoto
M
D000894:Anti-Inflammatory Agents, Non-Steroidal; D001692:Biological Transport / Q000187:drug effects; D002460:Cell Line; D045744:Cell Line, Tumor; D003110:Colonic Neoplasms; D016207:Cytokines / Q000494:pharmacology; D006801:Humans; D007413:Intestinal Mucosa; D008264:Macrophages; D008562:Membrane Glycoproteins / Q000187:drug effects / Q000235:genetics*; D026901:Membrane Transport Proteins / Q000187:drug effects / Q000235:genetics*; D013654:Taurine / Q000493:pharmacokinetics* / Q000494:pharmacology*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D000099247:Taurine Transporters
D000894:Anti-Inflammatory Agents, Non-Steroidal; D016207:Cytokines; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D013654:Taurine; D014409:Tumor Necrosis Factor-alpha; D000099247:Taurine Transporters