INS and obesity due to melanocortin 4 receptor deficiency: As mentioned in the previous sections, elevated tissue levels of 2-AG in Mgll−/− mice are associated with resistance to the metabolic alterations induced by a HFD as they accumulated less fat and became less glucose intolerant and insulin resistant than WT mice following HFD [156] and changes in Mgll−/− mice microbiome have been reported to contribute to their obesity resistant phenotype [156,157].