INS and obesity due to melanocortin 4 receptor deficiency: Conversely, expansions in BAT mass and increases in the circulating levels of BAT-derived secreted molecules (batokines) have been demonstrated by a growing body of literature to beneficially affect key physiological parameters such as glucose homeostasis, insulin sensitivity, and total energy expenditure, all of which confer resistance to the development of obesity-related metabolic dysfunction [21,22,23].