Fig 1.
Body Weight and Experimental Design of Weight Perturbation Studies.
Weight curves are presented for LF (solid circles; N = 18), HF (white squares; N = 16), CR (grey solid triangles; N = 20), and HF-LF (white diamonds; N = 25) mice (mean +/- SEM). Timing of physiological analyses is indicated by a black rectangle (48–51 weeks). Significant difference from LF is indicated by barred solid (HF), dashed (CR), and dotted lines (HF-LF); body weight of both CR and HF-LF groups were significantly different (P<0.0001) from HF mice at all time-points beside the initial time point for each mouse group. *** P<0.001.
Fig 2.
Body Composition, Circulating Leptin, Energy Expenditure and Fasting Glucose Concentrations of Weight Perturbed Mice.
Mouse groups are indicated by black (LF, N = 18), dark gray (HF, N = 16), light gray (CR, N = 20), and white (HF-LF, N = 25) bars for all panels. Data provided are Mean +/- SEM of phenotypes as indicated in Fig 1. (A) Body composition analysis is presented as both fat-free mass (solid bars) and fat mass (diagonal bars); statistical significance of differences between mouse groups is indicated for FFM at the bottom and FM at top of each bar. (B) Serum leptin, (C) Residual energy expenditure (See Experimental Procedures), and (D) Fasting glucose concentrations. *** P<0.001 compared to LF; † P<0.05, ††† P<0.001 compared to HF; ### P<0.001 between weight reduced groups.
Table 1.
Summary of Physiological Data.
Fig 3.
Visualization of STAT3 Phosphorylation in the Hypothalamus of LF mice.
(A-C) A representative example of pSTAT3 (brown) and hematoxylin (blue) staining in the hypothalamus is presented; ARH and VMH are indicated by green and yellow outlines, respectively. pSTAT3 staining intensity analyses are indicated as an overlay for positive (yellow) and negative (blue) pSTAT3 staining for the ARH (B) and VMH (C). (D-G) Increased magnification of a 100 micron section of ARH (D-E) or VMH (F-G) are presented, with analysis overlay in panels E and G, respectively.
Fig 4.
Intensity and Density of Nuclear STAT3 Phosphorylation Induced by Exogenous Leptin in Brain Regions of Weight Perturbed Mice.
A summary of leptin-induced (leptin minus saline) pSTAT3 immunohistochemistry data (mean +/- SEM) is presented for all brain regions analyzed (N = 3–5 per brain region; see S2 Table); LF (black), HF (dark gray), CR (light gray), and HF-LF (white) groups are indicated in panel A. pSTAT3 Nuclear Intensity Density was calculated as described in the Methods and represents the additive signal intensity of the entire region. Brain region is identified above each graph according to S1 Table. * P<0.05, ** P<0.01, *** P<0.001 compared to LF; † P<0.05, †† P<0.01, ††† P<0.001 compared to HF; # P<0.05, ## P<0.01 between weight reduced groups (CR & HF-LF).
Fig 5.
Summary of Changes in Intensity and Density of Nuclear pSTAT3 Induced by Exogenous Leptin When Compared to LF mice.
Leptin-induced (leptin minus saline) pSTAT3 nuclear intensity data for weight-perturbed mice is presented; HF (dark gray), CR (light gray), and HF-LF (white) groups (as indicated in the figure legend) are presented as a percentage of LF intensity levels. † P<0.05, †† P<0.01, ††† P<0.001 compared to HF; # P<0.05, ## P<0.01 between weight reduced groups (CR & HF-LF). Brain region identity is indicated below each graph according to S1 Table.
Table 2.
Summary of pSTAT3 Results by Brain Region Compared to Leptin-Induced pSTAT3 Levels (Leptin minus Saline) in LF Mice.
Table 3.
Classification of Region-Specific Leptin-Induced pSTAT3 Responses in Weight Perturbed Versus LF Mice.