Conjugated Linoleic Acid Attenuates the Production and Gene Expression of Proinflammatory Cytokines in Weaned Pigs Challenged with Lipopolysaccharide

Abstract

We investigated the anti-inflammatory role of conjugated linoleic acid (CLA) in inflammation-challenged weaned pigs and in in vitro cultured peripheral blood mononuclear cells (PBMCs). To test the hypothesis that inflammation responses can be attenuated by dietary CLA supplementation, we used an acute inflammation model in which pigs were injected with lipopolysaccharide (LPS). After 14 d of dietary supplementation with either 2% soybean oil or 2% CLA, half of the pigs in each diet group were challenged with LPS. Dietary CLA alleviated growth depression and prevented the elevations in production and mRNA expression of proinflammatory cytokines [i.e., interleukin (IL)-6 and tumor necrosis factor (TNF)-alpha] induced by the LPS challenge. CLA enhanced the expression of interleukin-10 (IL-10) and peroxisome proliferator-activated receptor-gamma (PPARgamma) in spleen and thymus. To further elucidate the inhibitory effects and the mechanism of action of CLA on cytokine profiles (i.e., IL-1beta, IL-6, and TNF-alpha), PBMCs were isolated from weaned pigs and cultured in media containing cis-9, trans-11 (9c,11t) CLA and trans-10, cis-12 (10t,12c) CLA. Each CLA isomer suppressed the production and expression of IL-1beta, IL-6, and TNF-alpha, and enhanced PPARgamma activation and gene expression in cultured PBMCs. At the molecular level, the inhibitory actions of CLA on IL-1beta, IL-6, and TNF-alpha are attributable mainly to 10t,12c-CLA and the anti-inflammatory properties of CLA are mediated, at least in part, through a PPARgamma-dependent mechanism.

Trans-10,cis-12-conjugated linoleic acid modulates NF-κB activation and TNF-α production in porcine peripheral blood mononuclear cells via a PPARγ-dependent pathway

“…Similarly, t10c12-CLA attenuated the production and gene expression of TNF-a in weaned pigs challenged with LPS (13) .…”

“…Some PPARg agonists, such as 15-deoxy-d 12,14 -PGJ 2 and troglitazone, inhibit the phorbol myristyl acetate-induced production of IL-1b, IL-6 and TNF-a in peripheral blood monocytes (12) . CLA isomers enhanced PPARg activation and attenuated the production of pro-inflammatory cytokines (IL-1b, IL-6 and TNF-a) in weaned pigs challenged with lipopolysaccharide (LPS) (13) . PPARg agonists might also possess pro-inflammatory activity through the inhibition of IL-10 activity mediated by the PPARg ligand 15-deoxy-d 12,14 -PGJ 2 ( 14) .…”

Interrelationship of feeding with immunity and parasitic infection: a review

“…lutein) has also a systemic pro-inflammatory influence in poultry (Koutsos et al, 2006). Feeding a conjugated linoleic acid-enriched diet, the inflammatory effect of LPSs in weaned piglets can be attenuated (Changhua et al, 2005).…”

Veterinary aspects and perspectives of nutrigenomics: A critical review

“…Moreover, CLAs induce apoptosis in adipocytes. The anti-inflammatory effect of some CLAs can be explained by the inhibition of proinflammatory cytokine mRNA expression, including interleukin-6 (IL-6), tumour necrosis factor α (TNFα) and, on the contrary, by the induction of gene expression of PPARγ both in vivo (in weaned piglets challenged with lipopolysaccharide) and in blood mononuclear cell culture (Changhua et al, 2005).…”