TFF3 and obesity due to melanocortin 4 receptor deficiency: In contrast, overexpression of Tff3 improved glucose tolerance in B6D2F1 mice fed an HFD for 6 weeks [12], in male Lepr db/Leprdb (db/db) mice and Leprob/Leprob (ob/ob) and in the diet-induced obesity mouse model (8-week-old C57BL/6 mice fed an HFD for more than 8 weeks) [13].