Cognitive impairment caused by compromised hepatic ketogenesis is prevented by endurance exercise.

Extensive research has demonstrated endurance exercise to be neuroprotective. Whether these neuroprotective benefits are mediated, in part, by hepatic ketone production remains unclear. To investigate the role of hepatic ketone production on brain health during exercise, healthy 6-month-old female rats underwent viral knockdown of the rate-limiting enzyme in the liver that catalyses the first reaction in ketogenesis: 3-hydroxymethylglutaryl-CoA synthase 2 (HMGCS2).

RNA-sequencing and behavioral testing reveals inherited physical inactivity co-selects for anxiogenic behavior without altering depressive-like behavior in Wistar rats.

Physical inactivity is positively associated with anxiety and depression. Considering physical inactivity, anxiety, and depression each have a genetic basis for inheritance, our lab used artificial selectively bred low-voluntary running (LVR) and wild type (WT) female Wistar rats to test if physical inactivity genes selected over multiple generations would lead to an anxiety or depressive-like phenotype. We performed next generation RNA sequencing and immunoblotting on the dentate gyrus to reveal key biological functions from heritable physical inactivity.

Sex dependent effects of physical activity on diet preference in rats selectively bred for high or low levels of voluntary wheel running.

Considering the current obesity epidemic is due in large part to an energy imbalance, it is crucial to explore biological mechanisms that mediate palatable high energy food intake and physical activity behavior levels. Previous research demonstrates a unique sex dependent influence of physical activity on diet preference, specifically changes in palatable high-fat diet intake. Therefore, factors of motivation may be underlying the differential effect of physical activity in male and female rats on their diet preference.

Sex determines effect of physical activity on diet preference: Association of striatal opioids and gut microbiota composition.

Previous studies suggest an interaction between the level of physical activity and diet preference. However, this relationship has not been well characterized for sex differences that may exist. The present study examined the influence of sex on diet preference in male and female Wistar rats that were housed under either sedentary (no wheel access) (SED) or voluntary wheel running access (RUN) conditions.

AMPK agonist AICAR delays the initial decline in lifetime-apex V̇o2 peak, while voluntary wheel running fails to delay its initial decline in female rats.

There has never been an outcome measure for human health more important than peak oxygen consumption (V̇o2 peak), yet little is known regarding the molecular triggers for its lifetime decline with aging. We examined the ability of physical activity or 5 wk of 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranoside (AICAR) administration to delay the initial aging-induced decline in lifetime-apex V̇o2 peak and potential underlying molecular mechanisms. Experiment 1 consisted of female rats with (RUN) and without (NO RUN) running wheels, while experiment 2 consisted of female nonrunning rats getting the AMPK agonist AICAR (0.

Fibroblast growth factor 2-stimulated proliferation is lower in muscle precursor cells from old rats.

In aged skeletal muscle, impairments in regrowth and regeneration may be explained by a decreased responsiveness of muscle precursor cells (MPCs) to environmental cues such as growth factors. We hypothesized that impaired responsiveness to fibroblast growth factor 2 (FGF2) in MPCs from old animals would be explained by impaired FGF2 signalling. We determined that 5-bromo-2'-deoxyuridine (BrdU) incorporation and cell number increase less in MPCs from 32- compared with 3-month-old rats.

Age-dependent FOXO regulation of p27Kip1 expression via a conserved binding motif in rat muscle precursor cells.

Previously, we have demonstrated that forkhead box O3a (FOXO3a) overexpression increased p27(Kip1) promoter activity and protein expression, whereas it decreased proliferation in muscle precursor cells (MPCs). The objectives of the present study were to 1) locate and identify FOXO regulatory elements in the rat p27(Kip1) promoter using deletion analysis of a promoter/reporter construct and 2) determine if age-related differences exist in FOXO-induced p27(Kip1) expression. The full-length (-4.

Skeletal muscle IGF-binding protein-3 and -5 expressions are age, muscle, and load dependent.

The purpose of the current study was to examine IGFBP-3, -4, and -5 mRNA and protein expression levels as a function of muscle type, age, and regrowth from an immobilization-induced atrophy in Fischer 344 x Brown Norway rats. IGFBP-3 mRNA expression in the 4-mo-old animals was significantly higher in the red and white portions of the gastrocnemius muscle compared with the soleus muscle. However, there were no significant differences in IGFBP-3 mRNA expression among any of the muscle groups in the 30-mo-old animals.