AHR and obesity due to melanocortin 4 receptor deficiency: Correspondingly, CH223191, an AhR antagonist, has been shown to stimulate adipocyte differentiation in normal preadipcytes derived from human primary preadipcytes [25], and a natural occurring AhR agonist indole-3-carbinol possesses anti-obesity activities in high fat diet-induced obese mice [26].