Fig. 2: Chronic activation of Arc POMC neurons failed to reduce body weight or obesity reversal.
From: The melanocortin action is biased toward protection from weight loss in mice
a Diagram depicting one side injection of AAV-Flex-NachBac-GFP virus to Arc POMC neurons. b Expression pattern of viral vector (GFP) and c-Fos (left panel) or c-Fos alone (right panel) showing c-Fos induction by NachBac expression. c Statistical comparison of c-Fos induction between the NachBac-injected side and the non-injection side of POMC-Cre male mice (n = 5/each, two-tailed paired t-tests, ***p = 0.0003). d, e Expression patterns showing that levels of both β-endorphin (d) and α-MSH (e) were increased in the NachBac-injected Arc side of POMC-Cre male mice (arrows). Arc: arcuate nucleus, 3 V: third ventricle. Scale bar: 50 µm. f, g Statistical comparisons for β-endorphin (f, n = 5/each, two-tailed paired t-tests, **p = 0.0011) and α-MSH (g, n = 5/each, two-tailed paired t-tests, ***p = 0.0001) expressions. h, i. Diagram depicting bilateral injection of NachBac or control GFP virus to the Arc of male POMC-Cre mice (h) and weekly body weight of these mice on chow feeding for 8 weeks (i). j Diagram depicting POMC-Cre mice were firstly fed HFD to induce obesity and then received NachBac injection to the bilateral Arc for body weight measurements. k Weekly body weight after viral delivery. l, m Comparison in fat mass (l, n = 8/each, two-tailed unpaired t-tests, p = 0.0807) and lean mass (m, n = 8/each, two-tailed unpaired t-tests, *p = 0.0312) between the two groups. n, o Comparisons between the two groups in feeding (n, n = 7/GFP and n = 8/NachBac, two-tailed unpaired t-tests, p = 0.2791) and locomotion (o, n = 8/each, two-tailed unpaired t-tests, p = 0.0856) measured between 2–3 weeks after viral injection when the body weight difference between the groups was minimal. All data were presented as mean ± SEM. Source data are provided in the Source Data file.
