Hypothalamic and brainstem <i>Nnat</i> expression after modified gastric bypass <i>versus</i> sham surgery.

<p>A) <i>Nnat</i>-β showed a significant reduction in the hypothalamus (**P = 0.003) after modified gastric bypass (n = 8) compared to sham surgery (n = 7) whilst <i>Nnat</i>-α did not reduce significantly, consistent with a bypass-specific effect on <i>Nnat</i>-β expression; B) expression of <i>Nnat</i>-α and <i>Nnat</i>-β did not differ in the brainstem after modified gastric bypass (n = 8) compared to sham surgery (n = 7); <i>key – GBP = modified gastric bypass surgery, Sham = sham surgery, AU = arbitrary units where Nnat expression was standardised using an endogenous reference gene (ubiquitin (Ubc) for hypothalamus, hypoxanthine guanine phosphoriboribosyl transferase (Hprt) for brainstem).</i></p

Changes in body-weight, leptin and gut hormones after surgery.

<p>GBP = modified gastric bypass surgery; data presented as Mean (Standard Error of Mean) or P value (<i>t</i> test).</p

Isoform-specific <i>Nnat</i> expression in the hypothalamus after surgery in relation to weight-loss and circulating leptin.

<p>A–B) <i>Nnat</i>-α expression in the hypothalamus did not correlate with either change in body-weight or with circulating leptin after surgery; C–D) by contrast <i>Nnat</i>-β expression showed positive correlation with change in body-weight and weak positive correlation with circulating leptin after surgery; <i>key – Nnat-α expression shown with open squares, Nnat-β with filled circles, AU = arbitrary units where Nnat expression was standardised using ubiquitin (Ubc) as a reference gene</i>.</p

Change in body weight and leptin after chronic dietary switches.

<p>Control = standard dietary chow maintained, Control-HF = standard dietary chow switch to high-fat diet, Control-CR = standard dietary chow switch to caloric restriction; HF-Control = high-fat diet switch to standard dietary chow, HF = high-fat diet maintained, HF-CR = high-fat diet switch to caloric restriction; data presented as P value (post-hoc ANOVA).</p

Expression of <i>Nnat</i> isoforms in response to fasting versus <i>ad-libitum</i> feeding.

<p>A) Hypothalamic <i>Nnat</i>-α and -β showed a non-significant reduction in response to overnight fasting (n = 10) when compared to <i>ad-libitum</i> fed counterparts (n = 10); B) but a significant reduction after 24-h fasting (n = 10) compared to feeding (n = 11), equivalent for both isoforms (**<i>Nnat</i>-α P = 0.005, **<i>Nnat</i>-β P = 0.007); C–D) <i>Nnat</i> isoforms did not show a consistent or significant change after overnight fasting in the stomach or duodenum (n = 10 fasted, n = 10 <i>ad-libitum</i> fed in both tissues); <i>key – AU = arbitrary units where Nnat expression was standardised using ubiquitin (Ubc) as a reference gene</i>.</p

Overlay between percentage (PCT) of mice within each strain that completed the experiment, left y-axis (transparent gray bars), and restriction wheel running activity (WRA) levels on day 1 (R1), day 2 (R2) and day 3 (R3) right y-axis (ranking based on the right y-axis); in 11 different mouse inbred strains, x-axis.

<p>Please note that because on R3, more than 80% of FVB strain mice were taken out of the experiment, the data for the remaining mice on this day (n = 2) are not shown. Strains with overall high activity levels and strains that increased their activity during the restriction days (e.g. DBA), are susceptible to the model.</p

Percentage (PCT) of mice within each strain that was susceptible to activity based anorexia model (ABA) i.e. that could not maintain the body weight above 85% of their baseline body weight.

<p>Percentage (PCT) of mice within each strain that was susceptible to activity based anorexia model (ABA) i.e. that could not maintain the body weight above 85% of their baseline body weight.</p

Baseline (Base) body weight (BW) (A), food intake (FI) (B), food intake corrected per body weight (FI/BW) (C) and wheel running activity (WRA) levels (D).

<p>The data are presented as mean ± SEM. The ranking for all graphs in this panel is based on baseline body weight.</p

Significant correlation between baseline wheel running activity (WRA) levels (x-axis) and restriction day 2 WRA levels (y-axis) across individual mice (n = 98) from 11 different mouse inbred strains (r_s = 0.767, P<0.0001).

<p>Significant correlation between baseline wheel running activity (WRA) levels (x-axis) and restriction day 2 WRA levels (y-axis) across individual mice (n = 98) from 11 different mouse inbred strains (r_s  = 0.767, P<0.0001).</p