6533b7d0fe1ef96bd125a4fb

RESEARCH PRODUCT

Effects of intrinsic aerobic capacity, aging and voluntary running on skeletal muscle sirtuins and heat shock proteins

Steven L. BrittonLauren G. KochPetra VainioSira KarvinenHeikki KainulainenLea SistonenMika Silvennoinen

subject

0301 basic medicineAgingmedicine.medical_specialtyphysical activityCitrate (si)-SynthaseOxidative phosphorylationta3111medicine.disease_causeBiochemistryRunning03 medical and health sciences0302 clinical medicineEndocrinologyPhysical Conditioning AnimalHeat shock proteinInternal medicineGeneticsmedicineAnimalsSirtuinsAerobic exerciseta318skeletal muscleta315Muscle Skeletaloksidatiivinen stressiMolecular BiologyHeat-Shock ProteinsAerobic capacitybiologyagingBody WeightSkeletal muscleRats Inbred StrainsCell BiologyHsp70sirtuinOxidative Stress030104 developmental biologymedicine.anatomical_structureEndocrinologySirtuinbiology.proteinFemaleEnergy Intake030217 neurology & neurosurgeryOxidative stress

description

Aim Sirtuins are proteins that connect energy metabolism, oxidative stress and aging. Expression of heat shock proteins (Hsps) is regulated by heat shock factors (HSFs) in response to various environmental and physiological stresses, such as oxidative stress. Oxidative stress accumulates during aging which makes cells more prone to DNA damage. Although many experimental animal models have been designed to study the effects of knockdown or overexpression of sirtuins, HSFs and Hsps, little is known about how aging per se affects their expression. Here we study the impact of intrinsic aerobic capacity, aging and voluntary exercise on the levels of sirtuins, HSFs and Hsps in skeletal muscle. Methods We studied the protein levels of sirtuins (SIRT1, SIRT2, SIRT3, SIRT4, SIRT5, SIRT6 and SIRT7), HSF1, HSF2, Hsp10, Hsp27 and Hsp70 before and after one-year of voluntary running intervention of rat strains selectively bred for intrinsic aerobic exercise capacity; high capacity runners (HCR) and low capacity runners (LCR) differ by more than 30% for median lifespan. This setup enabled us to discern the effects of inborn aerobic capacity, aging and exercise activity on the protein levels of sirtuins, HSFs and Hsps in skeletal muscle. Results Our results revealed that the longer lived HCR rats had higher SIRT3, HSF1 and HSF2 contents in skeletal muscle (gastrocnemius, p < 0.05) than LCRs. Neither aging nor voluntary running had a significant effect on the studied sirtuin proteins. Aging significantly increased the protein levels of HSF1, HSF2 and Hsp27 (p < 0.05). Conclusion Our finding of elevated SIRT3 levels in HCR rats is in line with previous studies; SIRT3 in general is linked to elevated fatty acid oxidation and oxidative phosphorylation, which previously have been associated with metabolic profile of HCRs. HSF1, HSF2 and Hsp27 levels increased with aging, showing that aged muscles responded to aging-related stress. Our study shows for the first time that SIRT3 protein level is linked to high inborn aerobic capacity, and may be directly interconnected to longevity. peerReviewed

yearjournalcountryeditionlanguage
2016-01-01Experimental Gerontology
https://doi.org/10.1016/j.exger.2016.03.015