We detected significant increases in the expressions of Cd45 and Il1b and an increasing trend for Tnfa expression in obese mice as compared to lean mice (p = 0.044, 0.025 and 0.052, respectively, DIO vs. lean mice, Figure 2A), suggesting the induction of inflammation in the mesocorticolimbic area by HFD-induced obesity. Here, IL1B is linked to obesity due to melanocortin 4 receptor deficiency.