IL-1β directly suppress ghrelin mRNA expression in ghrelin-producing cells

•IL-1β significantly suppresses ghrelin mRNA levels in MGN3-1 cells.•Ghrelin-producing cells express IL-1R.•The NF-κB pathway is involved in IL-1β-induced suppression of ghrelin.

In animal models, ghrelin production is suppressed by LPS administration. To elucidate the detailed molecular mechanisms involved in the phenomenon, we investigated the effects of LPS and LPS-inducible cytokines, including TNF-α, IL-1β, and IL-6, on the expression of ghrelin in the ghrelin-producing cell line MGN3-1. These cells expressed IL-1R, and IL-1β significantly suppressed ghrelin mRNA levels. The suppressive effects of IL-1β were attenuated by knockdown of IKKβ, suggesting the involvement of the NF-κB pathway. These results suggested that IL-1β is a major regulator of ghrelin expression during inflammatory processes.