Role of spleen-derived IL-10 in prevention of systemic low-grade inflammation by obesity [Review].

Obesity can be associated with systemic low-grade inflammation that leads to obesity-related metabolic disorders. Recent studies raise the possibility that the inflammation in hypothalamus, liver and white adipose tissue (WAT) contributes to the pathogenesis of diet-induced obesity. We focus on the role of interleukin (IL)-10, an anti-inflammatory cytokine produced from spleen in obesity because it is indicated that obesity decreases the expression of pro-inflammatory cytokines in spleen. Obesity results in decrease of IL-10 synthesis from spleen, probably due to reduction of B-cells expression by promoting oxidative stress and apoptosis in spleen. Splenectomy (SPX) aggravates the inflammatory response in hypothalamus, liver and WAT. These SPX-induced alterations are inhibited by systemic administration of IL-10. Moreover, in IL-10 deficiency, SPX had little effect on the inflammatory responses in these multiple organs. We show the role of spleen-derived IL-10 on inflammatory responses in obesity.