INS and obesity due to melanocortin 4 receptor deficiency: NF-E2-related factor 2 (NRF2)-Kelch-like ECH-associated protein 1 (KEAP1) pathway and endoplasmic reticulum (ER) stress are the two important factors in the primary adipocytes causing the risk of obesity (Wang et al., 2016); while curcumin and its metabolites are the signaling modulators to improve the lipolysis and insulin resistance for preventing obesity (Ye et al., 2017).