Induction of VF and exercise intensity.

<p>A. Current intensity and S₂ interval for VF induction in individual experiments for the 3 groups. B. Threshold current for VF induction in the studied groups (p<0.05 for ST compared to LT and CTRL, p<0.0001 for LT compared to CTRL). C. The relationship between the exercise intensity (the different groups) and the distribution of stimulus coupling interval S₂ that induces VF in the studied group (ST and LT compared to CTRL).</p

The effect of exercise on the in vivo (aerobic exercise capacity) and in vitro (cardiac output, systolic and diastolic function) measurements.

<p>CTRL, control group; ST, short term trained group; LT, long term trained group.</p

Heat acclimation induces tyrosine 654 phosphorylation of β catenin.

<p>Mice were subjected to CHI or sham operation, and injured cortexes were removed at 6 or 24β catenin, and Y654 β catenin was detected using western blots. Total β catenin was used as loading control (<b><i>A</i></b>). Immunostaining of the injured brain for Y654 β catenin (green) and DAPI (blue) shows induced Y654 β catenin phosphorylation restricted to injury area (<b><i>B</i></b>). Values represent the mean ± SEM. n = 5–6 per group. *<i>p</i><0.05 vs. NT mice, **<i>p</i><0.05 vs. sham mice, within the same group.</p

Heat acclimation (HA) induces improved motor recovery after TBI.

<p>Mice were subjected to CHI and motor ability was evaluated by the neurological severity score (<i>NSS</i>) at 1 h post injury for initial disability assessment and 1, 3 and 7 days thereafter. <i>ΔNSS</i> represent the recovery of injured mice as measured between 1 h post injury and any later time point, n = 9–12 per group (<b><i>A</i></b>). <b>Heat Acclimation (HA) reduces depressive like behavior after CHI</b>. Mice were subjected to CHI or sham operation and 24 h or 7 days thereafter to the forced swimming test. Immobility time was determined out of 240 seconds of record (<b><i>B</i></b>). Values represent the mean ± SEM. n = 5–6 per group. *<i>p</i><0.05 vs. normothermic (NT) mice, **<i>p</i><0.05 vs. sham mice within the same group.</p

Aerobic test protocol at weeks 1and 8 of the study.

<p>Aerobic test protocol at weeks 1and 8 of the study.</p

Schematic representation of suggested sequent of events determining β catenin fate in heat acclimated mice after closed head injury (CHI).

<p>In the first hours after CHI, basal high levels of brain derived neurotrophic factor (BDNF) and N-cadherin lead to abrupt increase of Akt phosphorylation upon CHI, resulting in inhibition of c-Jun N-terminal kinase (JNK) and glycogen kinase 3β (GSK3β). Inhibited GSK3β may lead to reduced ser33/37thr41 phosphorylation of β catenin later on. Increased ser33/37thr41 phosphorylation of β catenin implies on involvement of another player, potentially another kinase or hypoxia inducible factor 1α (HIF1α). Simultaneously, high levels of BDNF consequence in induced tyrosine 654 phosphorylation of β catenin, superior to the ser33/37thr41 phosphorylation which allows β catenin to escape degradation or nuclear translocation. Those events lead to weakening the catenin-cadherin complex in cell membrane, enabling synaptic changes at 1 day post injury. 1 week after the injury, β catenin translocates back to newly created synapses to form cadherin-catenin complex and establish cell-cell adhesion.</p

Heat acclimation induces basal N-cadherin and post injury detachment of the cadherin-catenin complex.

<p>Representative western blots of N cadherin, showing significant basal induction of N cadherin which lasts up to 6(HA) as compared with normothermic mice (NT) (<i>A</i>). β-catenin was immunoprecipitated (IP) with protein A beads and separated on SDS-PAGE gels. Immunoblotting (IB) of N cadherin indicates disassociation of cadherin-catenin complex in injured HA mice. (−) Immunoprecipitation of non β-catenin related protein (Bcl-xL) with the same beads. (+) input from non immunoprecipitation blot of 60 µg protein from injured HA brain (<b><i>B</i></b>). Values represent the mean ± SEM. n = 5–6 per group. *<i>p</i><0.05 vs. NT mice, **<i>p</i><0.05 vs. sham mice, within the same group.</p

Heat acclimation induces transient reduction in membrane β-catenin and synaptophysin.

<p>Membrane cellular fraction extracts were separated on SDS-PAGE gels and analyzed using western blotting. After the injury a significant reduction in membrane bound β-catenin were seen at 72 h post injury in heat acclimated (HA) mice and after 7 days in normothermic (NT) mice. Membrane bound β-catenin levels were recovered by 7 days after injury (<b><i>A</i></b>) Blots of membrane extracts show significant reduction in synaptophysin levels in both groups at 72 h after injury with a recovery seen only in HA mice by 7 days post injury (<b><i>B</i></b>). The absence of synaptophysin in the cytosol verifies membrane protein enrichment. Values represent the mean ± SEM. n = 5–6 per group. *<i>p</i><0.05 vs. NT mice, **<i>p</i><0.05 vs. sham mice,within the same group.</p

HA induces inhibition of glycogen synthase kinase 3β (GSK3β) and c-Jun N terminal kinase (JNK).

<p>Mice were subjected to CHI or sham operation, and injured cortexes were removed at 6, 12 or 24β showing significant inhibition of GSK3β by 24 h post injury in heat acclimated mice (HA) as compared with normothermic mice (NT) (<b><i>A</i></b>). Representative western blots of JNK phosphorylation, that is related to enhanced kinase activity, showing reduced JNK activity in HA mice after CHI (<b><i>B</i></b>). Values represent the mean ± SEM. n = 5–6 per group. *<i>p</i><0.05 vs. NT mice, **<i>p</i><0.05 vs. sham HA mice.</p

Heart rate variability measures.

<p>A. Poincare plots for sample CTRL and LT animals (comparison of ST group to CTRL was not significant, not shown). B. HRV parameters for the 3 groups relative to their normalized value at week 1 in %.</p