LEPR and obesity due to melanocortin 4 receptor deficiency: We also observed a similar loss of expression of mature miR-184 in the islets of 12-week-old leptin receptor-deficient db/db mice and in mice on a high-fat diet (HFD; 60% calories from fat), all of which showed that this observation is not limited to one mouse model of obesity and insulin resistance (Figures 1E and 1F).