LEP and diabetes mellitus: However, at 5 weeks of age we observed no difference in AIS length between control (28.58 ± 0.36 μm, n = 4 mice) and db/db (28.21 ± 0.65 μm, n = 4 mice) mice (p = 0.6280, unpaired t-test; Figures 3A,C,E), suggesting that lack of leptin signaling does not impact AIS formation in db/db mice before overt signs of diabetes develop.