CNR1 and obesity due to melanocortin 4 receptor deficiency: CB1R stimulation affects changes in food intake (Silvestri and Di Marzo, 2013; Krug and Clark, 2015) and promotes obesity, while downregulation of CB1R leads to a reduction of appetite (Osei-Hyiaman et al., 2005; Gary-Bobo et al., 2007; Shimada et al., 2012).