GPX4 and obesity due to melanocortin 4 receptor deficiency: Since GPX4 is a key regulator of ferroptosis, we finally investigated whether Gpx4 deficiency‐mediated ferroptosis in macrophages is involved in the development of obesity‐associated insulin resistance by performing transcriptomic analysis on BMDMs derived from Gpx4Mac‐KO and Gpx4fl/fl mice.