Ghrelin promotes nuclear factor kappa-B activation in a human B-lymphocyte cell line

Abstract

Ghrelin, an orexigenic hormone of gastric origin that stimulates growth hormone secretion, may modulate inflammation. This experimental study examines the effect of ghrelin on NFκB (p65 subunit), a transcriptional factor involved in inflammation on a human B-lymphocyte cell (WILCL). After confirming the expression of ghrelin receptor protein using western blotting the cells were transferred to wells maintaining a density of 1 × 10(6) cells per ml and a proportion activated with phytohaemagluttinin. Activated and resting cells were exposed to octanoyl-, desoctanoyl ghrelin and a non-peptide ghrelin agonist (Pfizer CP-464709) in increasing concentrations for 6 h. Cell protein extracts were analyzed for NFκB activation using Trans AM NFκB p65 assay. IL-6, IL-8, IL-10, IL-13 and TNFα were measured in the media using Lincoplex human cytokine assay. In octanoyl ghrelin treated resting cells, NFκB activity (Optical Density OD(450 nm)) (mean ± SEM) in control cells was 0.42 ± 0.10 and increased to 0.61 ± 0.20 (P = 0.044), 0.54 ± 0.10 (P = 0.043), 0.52 ± 0.08 at 1, 10 and 100 nM concentrations respectively. No effect was detected with desoctanoyl ghrelin or ghrelin agonist and no specific change in cytokine production. In conclusion, Octanoyl ghrelin increased NFκB activation by up to 50% in a B-lymphocyte cell line suggesting an effect on the inflammatory process.