Inherited physical capacity: Widening divergence from young to adult to old

Kemi, O. J. , Hoydal, M. A., Haram, P. M., Smith, G. L. , Ellingsen, O., Koch, L. G., Britton, S. L. and Wisloff, U. (2024) Inherited physical capacity: Widening divergence from young to adult to old. Annals of the New York Academy of Sciences, (doi: 10.1111/nyas.15130) (PMID:38520387) (Early Online Publication)

Abstract

Cardiorespiratory performance segregates into rat strains of inherited low- and high-capacity runners (LCRs and HCRs); during adulthood, this segregation remains stable, but widens in senescence and is followed by segregated function, health, and mortality. However, this segregation has not been investigated prior to adulthood. We, therefore, assessed cardiorespiratory performance and cardiac cell (cardiomyocyte) structure–function in 1- and 4-month-old LCRs and HCRs. Maximal oxygen uptake was 23% less in LCRs at 1-month compared to HCRs at 1-month, and 72% less at 4 months. Cardiomyocyte contractility was 37−56% decreased, and Ca2+ release was 34−62% decreased, in 1- and 4-month LCRs versus HCRs. This occurred because HCRs had improved contractility and Ca2+ release during maturation, whereas LCRs did not. In quiescent cardiomyocytes, LCRs displayed 180% and 297% more Ca2+ sparks and 91% and 38% more Ca2+ waves at 1 and 4 months versus HCRs. Cell sizes were not different between LCRs and HCRs, but LCRs showed reduced transverse-tubules versus HCRs, though no discrepant transverse-tubule generation occurred during maturation. In conclusion, LCRs show reduced scores for aerobic capacity and cardiomyocyte structure–function compared to HCRs and there is a widening divergence between LCRs and HCRs during juvenile to near-adult maturation.

• Item Type: Articles
• Keywords: adolescence, calcium, cardiomyocyte, inheritance, exercise, fitness, maturation.
• Status: Early Online Publication
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Smith, Professor Godfrey and Kemi, Dr Ole
• Authors: Kemi, O. J., Hoydal, M. A., Haram, P. M., Smith, G. L., Ellingsen, O., Koch, L. G., Britton, S. L., and Wisloff, U.
• College/School: College of Medical Veterinary and Life Sciences > School of Cardiovascular & Metabolic Health
• Journal Name: Annals of the New York Academy of Sciences
• Publisher: New York Academy of Sciences
• ISSN: 0077-8923
• ISSN (Online): 1749-6632
• Published Online: 24 March 2024
• Copyright Holders: Copyright: © 2024 The Authors
• First Published: First published in Annals of the New York Academy of Sciences 2024
• Publisher Policy: Reproduced under a Creative Commons licence