title: The role of continuous versus fractionated physical training on muscle oxidative stress parameters and calcium-handling proteins in aged rats.
abstract: Age-associated decline in skeletal muscle mass and strength is associated with oxidative stress and Ca(2+) homeostasis disturbance. Exercise should be considered a viable modality to combat aging of skeletal muscle. This study aimed to investigate whether continuous and fractionated training could be useful tools to attenuate oxidative damage and retain calcium-handling proteins. We conducted the study using 24-month-old male Wistar rats, divided into control, continuous, and fractionated groups. Animals ran at 13 m min(-1) for five consecutive days (except weekends) for 6 weeks, for a total period of 42 days. Each session comprised 45 min of exercise, either continuous or divided into three daily sessions of 15 min each. Metabolic and oxidative stress markers, protein levels of mitochondrial transcription factors, and calcium-handling proteins were analyzed. Continuous exercise resulted in reduced ROS production as well as showed a decrease in TBARS levels and carbonyl content. On the other hand, fractionated training increased the antioxidant enzyme activities. The ryanodine receptor and phospholamban protein were regulated by continuous training while sodium calcium exchange protein was increased by the fractionated training. These data suggest that intracellular Ca(2+) can be modulated by various training stimuli. In addition, the modulation of oxidative stress by continuous and fractionated training may play an important regulatory role in the muscular contraction mechanism of aged rats, due to changes in calcium metabolism.
authors.affiliation: Laboratory of Exercise Biochemistry and Physiology, Graduate Program in Health Sciences, Health Sciences Unit, Universidade do Extremo Sul Catarinense, Av. Universitária, 1105 Bairro Universitário, Criciúma, SC, 88806-000, Brazil.
authors.forename: Camila B
authors.initials: CB
authors.lastname: Tromm
authors.affiliation: Laboratory of Exercise Biochemistry and Physiology, Graduate Program in Health Sciences, Health Sciences Unit, Universidade do Extremo Sul Catarinense, Av. Universitária, 1105 Bairro Universitário, Criciúma, SC, 88806-000, Brazil.
authors.forename: Bruna G
authors.initials: BG
authors.lastname: Pozzi
authors.affiliation: Laboratory of Exercise Biochemistry and Physiology, Graduate Program in Health Sciences, Health Sciences Unit, Universidade do Extremo Sul Catarinense, Av. Universitária, 1105 Bairro Universitário, Criciúma, SC, 88806-000, Brazil.
authors.forename: Carla S
authors.initials: CS
authors.lastname: Paganini
authors.affiliation: Laboratory of Exercise Biochemistry and Physiology, Graduate Program in Health Sciences, Health Sciences Unit, Universidade do Extremo Sul Catarinense, Av. Universitária, 1105 Bairro Universitário, Criciúma, SC, 88806-000, Brazil.
authors.forename: Scherolin O
authors.initials: SO
authors.lastname: Marques
authors.affiliation: Laboratory of Exercise Biochemistry and Physiology, Graduate Program in Health Sciences, Health Sciences Unit, Universidade do Extremo Sul Catarinense, Av. Universitária, 1105 Bairro Universitário, Criciúma, SC, 88806-000, Brazil.
authors.forename: Giulia S
authors.initials: GS
authors.lastname: Pedroso
authors.affiliation: Laboratory of Exercise Biochemistry and Physiology, Graduate Program in Health Sciences, Health Sciences Unit, Universidade do Extremo Sul Catarinense, Av. Universitária, 1105 Bairro Universitário, Criciúma, SC, 88806-000, Brazil.
authors.forename: Priscila S
authors.initials: PS
authors.lastname: Souza
authors.affiliation: Laboratory of Exercise Biochemistry and Physiology, Graduate Program in Health Sciences, Health Sciences Unit, Universidade do Extremo Sul Catarinense, Av. Universitária, 1105 Bairro Universitário, Criciúma, SC, 88806-000, Brazil.
authors.forename: Paulo C L
authors.initials: PC
authors.lastname: Silveira
authors.affiliation: Laboratory of Exercise Biochemistry and Physiology, Graduate Program in Health Sciences, Health Sciences Unit, Universidade do Extremo Sul Catarinense, Av. Universitária, 1105 Bairro Universitário, Criciúma, SC, 88806-000, Brazil.
authors.forename: Luciano A
authors.initials: LA
authors.lastname: Silva
authors.affiliation: Laboratory of Exercise Biochemistry and Physiology, Graduate Program in Health Sciences, Health Sciences Unit, Universidade do Extremo Sul Catarinense, Av. Universitária, 1105 Bairro Universitário, Criciúma, SC, 88806-000, Brazil.
authors.forename: Claudio T
authors.initials: CT
authors.lastname: De Souza
authors.affiliation: Laboratory of Exercise Biochemistry and Physiology, Graduate Program in Health Sciences, Health Sciences Unit, Universidade do Extremo Sul Catarinense, Av. Universitária, 1105 Bairro Universitário, Criciúma, SC, 88806-000, Brazil. pinho@unesc.net.
authors.forename: Ricardo A
authors.initials: RA
authors.lastname: Pinho
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D008297:Male; D008928:Mitochondria / Q000378:metabolism; D009119:Muscle Contraction / Q000502:physiology; D053580:Muscle Strength / Q000502:physiology; D018482:Muscle, Skeletal / Q000502:physiology; D010084:Oxidation-Reduction; D018384:Oxidative Stress / Q000502:physiology*; D010805:Physical Conditioning, Animal / Q000379:methods / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D019837:Ryanodine Receptor Calcium Release Channel / Q000378:metabolism; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
chemical_list: D002135:Calcium-Binding Proteins; D019837:Ryanodine Receptor Calcium Release Channel; D017392:Thiobarbituric Acid Reactive Substances; D002118:Calcium
keywords: Aging; Calcium; Oxidative stress; Physical exercise; Skeletal muscle