Comparison of Gene and Protein Expressions in Rats Residing in Standard Cages with Those Having Access to an Exercise Wheel

Abstract

Lifelong physical inactivity is associated with morbidity in adulthood, possibly influenced by changes in gene and protein expressions occurring earlier in life. mRNA (Affymetrix gene array) and proteomic (2D-DIGE MALDI-TOF/MS) analyses were determined in cardiac tissue of young (3 months) and old (16 months) Sprague-Dawley rats housed with no access to physical activity (SED) versus an exercise wheel (EX). Unfavorable phenotypes for body weight, dyslipidemia, and tumorogenesis appeared more often in adult SED versus EX. No differentially expressed genes (DEGs) occurred between groups at 3 or 16 months. Within groups, SED and EX shared 215 age-associated DEGs. In SED, ten unique DEGs occurred with age; three had cell adhesion functions (fn1, lgals3, ncam2). In EX, five unique DEGs occurred with age; two involved hypothalamic, pituitary, and gonadal hormone axis (nrob2, xpnpep2). Protein expression involved in binding, sugar metabolic processes, and vascular regulation declined with age in SED (KNT1, ALBU, GPX1, PYGB, LDHB, G3P, PYGM, PGM1, ENOB). Protein expression increased with age in EX for ATP metabolic processes (MYH6, MYH7, ATP5J, ATPA) and vascular function (KNT1, ALBU, GPX1). Differences in select gene and protein expressions within sedentary and active animals occurred with age and contributed to distinct health-related phenotypes in adulthood.

Epigenetic Regulatory Effect of Exercise on Glutathione Peroxidase 1 Expression in the Skeletal Muscle of Severely Dyslipidemic Mice

“…A study has previously shown that low activity of Gpx1 is an independent risk factor of cardiovascular events [ 60 ]. The increase in Gpx1 with exercise is also coherent with the literature [ 61 , 62 ] and concords with the known antioxidant properties of chronic exercise [ 16 , 17 ]. Therefore, our data, in support of the current knowledge, suggest that overexpression of Gpx1 is one of the mechanisms responsible for the antioxidant protection by exercise.…”

Mitochondrial and Metabolic Gene Expression in the Aged Rat Heart

“…Cardiac gene expression changes due to exercise training in young rats have been well-studied. These studies showed that mitochondrial or metabolic gene expression in the young rat heart to either increase (Hall et al, 1994 ; Rimbaud et al, 2009 ; Dobrzyn et al, 2013 ; Wadley et al, 2016 ) or not change (Murakami et al, 1995 ; Iemitsu et al, 2003 ; Alessio et al, 2014 ) with exercise training compared to young sedentary rats. Specifically, young hearts respond to exercise training by increasing the expression of genes associated with glucose transport (Hall et al, 1994 ; Rimbaud et al, 2009 ), fatty acid oxidation (Rimbaud et al, 2009 ; Dobrzyn et al, 2013 ), and mitochondrial biogenesis (i.e., PGC-1α and Cox4il; Rinaldi et al, 2013 ; Wadley et al, 2016 ).…”

Genetics of Regular Exercise and Sedentary Behaviors

“…We have to concur with Santos et al (2014) that there is a clear necessity to continue efforts to unravel the effects of the various physical activity traits on the expression of genetic variance in body composition. Alessio et al (2014) used a rat model to test whether exercise modulates the normal aging of the heart muscle. They compare the whole genome gene expression profile as well as cardiac proteomics signature of rats aged 3 months and 16 months.…”

“…Alessio et al (2014) used a rat model to test whether exercise modulates the normal aging of the heart muscle. They compare the whole genome gene expression profile as well as cardiac proteomics signature of rats aged 3 months and 16 months.…”