ATF3 and obesity due to melanocortin 4 receptor deficiency: We then showed that inducing ATF3 has substantial metabolic benefits, and an ATF3 inducer, ST32da, could inhibit adipocyte lipogenesis/adipogenesis, enhance UCP1 expression, and promote white adipocyte browning in vitro, in addition to inhibiting obesity and restoring normal insulin sensitivity in HFD-fed obese mice.