Original Research ARTICLE
The endothelial mechanotransduction protein Platelet Endothelial Cell Adhesion Molecule-1 is influenced by aging and exercise training in human skeletal muscle
- 1Department of Nutrition, Exercise and Sports, University of Copenhagen, Denmark
- 2Liverpool John Moores University, United Kingdom
Aim: The aim was to determine the role of aging and exercise training on endothelial mechanosensor proteins and the hyperemic response to shear stress by passive leg movement (PLM). Method: We examined the expression of mechanosensor proteins and vascular function in young (n=14, 25±3 years) and old (n=14, 72±5 years) healthy male subjects with eight weeks of aerobic exercise training. Before and after training, the hyperaemic response to PLM was determined and a thigh muscle biopsy was obtained before and after PLM to assess the acute effect of increased shear stress. Biopsies were analyzed for protein amount and phosphorylation of mechanosensor proteins; Platelet endothelial cell adhesion molecule-1 (PECAM-1), Vascular endothelial cadherin, Vascular endothelial growth factor receptor-2 and endothelial nitrc oxide synthase (eNOS). Results: Before training, the old group presented a lower hyperaemic response to PLM and a 35% lower (p<0.05) relative basal phosphorylation level of PECAM-1 whereas there was no difference for the other mechanosensor proteins. After training, the eNOS protein amount, the amount of PECAM-1 protein and the PLM-induced phosphorylation of PECAM-1 were higher in both groups. The hyperaemic response to PLM was higher after training in the young group only. Conclusion: Aged individuals have a lower hyperaemic response to passive leg movement and a lower relative basal phosphorylation of PECAM-1 than young. The higher PECAM-1 phosphorylation despite a similar hyperemic level in the aged observed after training, suggests that training improved shear stress responsiveness of this mechanotransduction protein.
Keywords: Vascular function, Passive leg movement, mechanosensors, Aging - old age - seniors, shear stress
Received: 06 Sep 2018;
Accepted: 30 Nov 2018.
Edited by:Per Hellstrand, Lund University, Sweden
Copyright: © 2018 Gliemann, Rytter, Piil, Nilton, Lind, Nyberg, Cocks and Hellsten. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Dr. Lasse Gliemann, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, 2200, Capital Region of Denmark, Denmark, email@example.com