Wolfrum and coworkers reported an increase in both TIMP1 serum concentrations and adipose tissue protein levels in mouse models of obesity compared with lean control animals [156], confirming earlier results showing increased TIMP1 expression in obese adipose tissue of Ob/Ob, db/db and mice submitted to a HFD [31]. Here, TIMP1 is linked to obesity due to melanocortin 4 receptor deficiency.