In obesity, increased levels of TGF-β1 in the adipose tissue and/or in the lung have been observed in obese humans, mice, rats, and drosophila (Samad et al., 1997; Yadav et al., 2011, Jung et al., 2013; Sousa-Pinto et al., 2016; Lee, 2018; Park et al., 2019) (Table 1). Here, TGFB1 is linked to obesity due to melanocortin 4 receptor deficiency.