IL6 and obesity due to melanocortin 4 receptor deficiency: Indeed, we show that deletion of netrin-1, specifically in myeloid cells, reduced VAT macrophage burden and decreased systemic and local markers of inflammation, including circulating levels of IL-6 and VAT levels of pro-inflammatory metabolites of arachidonic acid (e.g., prostaglandins and leukotrienes) known to promote persistent inflammation and altered lipid metabolism in obesity [60,61].