MRC1 and obesity due to melanocortin 4 receptor deficiency: This indicates that the vast majority of macrophages in the PEC do not express markers such as CD206 or CD11c, but express CCR2, CCR5, and CXCR4 with HFD, which may contribute to the “macrophage disappearance.” Therefore, CCR2 increases in microglia and macrophages in the hypothalamus in obesity, while microglia additionally upregulate CXCR4.