TNF and obesity due to melanocortin 4 receptor deficiency: In the other hand, a low dose of icv TNFα, mimicing some of the features of low-grade/obesity-like hypothalamic inflammation, reduced UCP1 and PGC1α expression and inhibiting mitochondrial biogenesis in the BAT and resulted in reduced O2 consumption/CO2 production (Arruda et al., 2011).