Biol. Pharm. Bull., 29(6),1102-1109, June 2006

Regular Articles

Differential Regulation of Eotaxin-1/CCL11 and Eotaxin-3/CCL26 Production by the TNF-α and IL-4 Stimulated Human Lung Fibroblast

Akiko ROKUDAI,^a,b Yasuhito TERUI,^a Ryoko KUNIYOSHI,^a,b Yuji MISHIMA,^a Yuko MISHIMA,^a Eriko AIZU-YOKOTA,^b Yoshiko SONODA,^b Tadashi KASAHARA,^*,b and Kiyohiko HATAKE^*,a

^a Division of Clinical Chemotherapy, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research; 3-10-6 Ariake, Koutou-ku, Tokyo 135-8550, Japan: and ^b Department of Biochemistry, Kyoritsu University of Pharmacy; 1-5-30 Shibakoen, Minato-ku, Tokyo 105-8512, Japan. * To whom correspondence should be addressed. e-mail: khatake@jfcr.or.jp; kasahara-td@kyoritsu-ph.ac.jp

Allergic asthma and allergic dermatitis are chronic inflammatory diseases and are characterized by an accumulation of eosinophils at sites of inflammation. Eotaxin-1/CCL11 and eotaxin-3/CCL26 are members of the CC chemokine family, which are known to be potent chemoattractants for eosinophils. We observed that a human lung fibroblast, HFL-1 produces eotaxin-1 and -3 in response to TNF-α plus IL-4 stimulation, accompanied with NF-κB and STAT6 activation. We explored which signaling pathways are operative in the production of eotaxin-1 and -3 using several inhibitors. Eotaxin-1/CCL11 production was inhibited by a p38 mitogen-activated protein kinase (MAPK) inhibitor, SB203580, but not by the MEK (MAPK/ERK kinase) inhibitors, PD98059 and U0126. In contrast, eotaxin-3/CCL26 production was inhibited similarly by PD98059 as well as U0126 and SB203580. In addition, two proteasome inhibitors, N-acetyl-leucyl-leucyl-norleucinal (ALLN) and bortezomib with significant inhibitory activity on NF-κB activation, inhibited eotaxin-1/CCL11 production with IC₅₀ 8 μM for ALLN and IC₅₀ 16 nM for bortezomib. In contrast, eotaxin-3/CCL26 production was not inhibited significantly up to 10 μM of ALLN (IC₅₀ 16 μM) and up to 10 nM of bortezomib (IC₅₀ 11 nM), giving inhibition of eotaxin-3/CCL26 less sensitive than eotaxin-1/CCL11 production by the proteasome inhibitors. Synergistic inhibition was observed among lower doses of SB203580 and proteasome inhibitors, particularly in the eotaxin-1/CCL11 production. No such prominent synergism was found on the eotaxin-3/CCL26 production. The suppression of eotaxin family production by these inhibitors may be efficacious against allergic diseases.

Key words eotaxin-1; eotaxin-3; lung fibroblast; NF-κB activation; proteasome inhibitor