Inhibition of interleukin-8 release in the human colonic epithelial cell line HT-29 by cannabinoids

We have investigated the effects of cannabinoid agonists and antagonists on tumour necrosis factor-alpha (TNF-alpha)-induced secretion of interleukin-8 from the colonic epithelial cell line, HT-29. The cannabinoid receptor agonists {(-)-3-[2-hydroxy-4-(1,1-dimethyl-heptyl)phenyl]4-[3-hydroxypropyl]cyclo-hexan-1-ol} (CP55,940); Delta-9-tetrahydrocannabinol; [R(+)-[2,3-dihydro-5-methyl-3-[(morpholinyl) methyl] pyrrolo[1,2,3-de]1,4-benzoxazin-6-yl](1-naphthyl) methanone mesylate} (WIN55,212-2) and 1-propyl-2-methyl-3-naphthoylindole (JWH 015) inhibited TNF-a induced release of interleukin-8 in a concentration-dependent manner. The less active enantiomer of WIN55212-2, [S(-)-[2,3-dihydro-5-methyl-3-[(morpholinyl)methyl]pyrrolo[1,2,3-de]1,4-benzoxazin-6-yl](1-naphthyl) methanone mesylate (WIN55212-3), and the cannabinoid CB1 receptor agonist arachidonoyl-2-chloroethylamide (ACEA) had no significant effect on TNF-alpha-induced release of interleukin-8. The cannabinoid CB, receptor antagonist N-(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4dichlorophenyl)-4-methyl-1,4-pyrazole-3-carboxamide hydrochloride (SR141716A; 10(-6) M) antagonised the inhibitory effect of CP55,940 (pA(2) = 8.3 +/- 0.2, n = 6) but did not antagonise the inhibitory effects of WIN55212-2 and JWH 015. The cannabinoid CBz receptor antagonist N-(1,S)-endo1,3,3-trimethylbicyclo(2,2,1)heptan-2-yl)-5(4-chloro-3-methyl-phenyl)-1-(4-methylbenzyl)-pyrazole-3-carboxamide (SR144528; 10(-6) M) antagonised the inhibitory effects of CP55,940 (pA2=8.2 0.8, n=6), WIN55212-2 (pA(2)=7.1 +/- 0.3, n=6) and JWH 015 (pA2=7.6 +/- 0.3, n=6), respectively. Western immunoblotting of HT-29 cell lysates revealed a protein with a size that is consistent with the presence of cannabinoid CBz receptors. We conclude that in HT-29 cells, TNF-a-induced interleukin-8 release is inhibited by cannabinoids through activation of cannabinoid CBz receptors. (C) 2002 Elsevier Science B.V. All rights reserved.