IL-1ß directly suppress ghrelin mRNA expression in ghrelin-producing cells.

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-1ß, and IL-6, on the expression of ghrelin in the ghrelin-producing cell line MGN3-1. These cells expressed IL-1R, and IL-1ß significantly suppressed ghrelin mRNA levels. The suppressive effects of IL-1ß were attenuated by knockdown of IKKß, suggesting the involvement of the NF-κB pathway. These results suggested that IL-1ß is a major regulator of ghrelin expression during inflammatory processes.