Consistently, our in vitro study found that DCA could significantly up-regulate Ccl2 expression in both macrophage and colonic cell line in a dose-dependent manner (data not shown), which implies the important role of excessive DCA in the recruitment of colonic macrophages under the HFD settings, together with our peritoneal injection data exhibiting that DCA administration elicited a considerable increase in the recruitment of macrophages, thus these findings indicate that DCA crucially contributes to the HFD-induced pro-inflammatory macrophages infiltration and colonic inflammation. This evidence concerns the gene CCL2 and colitis.