Submitted to: Journal of Animal Science
Publication Type: Abstract Only
Publication Acceptance Date: July 13, 2006
Publication Date: July 30, 2006
Citation: Weber, T.E., Chitko Mckown, C.G., Kerr, B.J. 2006. The effect of butyrate on cytokine production and proliferation by porcine monocytes. Journal of Animal Science. 89(1):308. Technical Abstract: Although butyrate modulates proliferation and cytokine production by peripheral blood mononuclear cells PBMC in some species, the role of butyrate as a regulator of immunocyte function in the pig has not been studied. Therefore, the primary objective of this study was to determine whether butyrate influences the proliferation, cytokine secretion, and mRNA expression by porcine immune cells in vitro. For experiments using peripheral blood mononuclear cells (PBMC)was collected from healthy pigs (n = 6)to test the effect of sodium butyrate (0, 0.2, or 2.0 mM) on the blastogenic response to concanavilin A (Con A; 5 microgram/mL), and cytokine expression and secretion. Cytokine mRNA abundance was determined using real-time reverse transcriptase PCR procedures, and cytokine secretion was measured via enzyme-linked immuno assay (ELISA) methodology. Butyrate at 2.0 mM, but not 0.2 mM, suppressed (P < 0.05) Con A-induce PBMC proliferation, yet led to a paradoxical increase (P < 0.05) in interleukin-2 (IL-2) mRNA expression. The secretion and mRNA expression of interferon-gamma (IFN-gamma) by Con A-activated PBMC was increased several-fold (P < 0.05) by butyrate at 2.0 mM. Treating the Con A-activated PBMC with butyrate at 2.0 mM decreased (P < 0.05) the secretion of IL-10. In contrast, butyrate at 0.2 mM increased (P < 0.05) both IL-10 secretion and mRNA expression. To test the direct effect of butyrate on cytokine expression by porcine macrophages, cells from a porcine monocyte-derived macrophage cell-line were cultured with E. coli. lipopolysaccharide (LPS;10 microgram/mL) in the presence or absence of sodium butyrate (2.0 mM). Activating the macrophages with LPS increased (P < 0.05) the mRNA expression of tumor necrosis factor-alpha (TNF-alpha) at 2 hours post treatment and IL-6 at 2 hours and 4 hours post treatment. Treating the activated-macrophages with sodium butyrate tended (P < 0.07) to decrease the expression of TNF-alpha at 2 hours and partially reversed (P < 0.05) the induction of IL-6 by LPS at 4 hours post treatment. These data indicate that the effect of butyrate on proliferation and cytokine production by porcine PBMC is dose-dependent, and provide evidence that butyrate decreases the expression of inflammatory cytokines by porcine macrophages.