Forskning ved Københavns Universitet - Københavns Universitet


Impact of TGF-β inhibition during acute exercise on Achilles tendon extracellular matrix

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningfagfællebedømt

  • Ross M Potter
  • Richard T Huynh
  • Brent D Volper
  • Kathryn A Arthur
  • Andrew C D'Lugos
  • Mikkel A Sørensen
  • Magnusson, Stig Peter
  • Jared M Dickinson
  • Taben M Hale
  • Chad C Carroll

The purpose of this study was to evaluate the role of TGF-β1in regulating tendon extracellular matrix after acute exercise. Wistar rats exercised (n = 15) on a treadmill for four consecutive days (60 min/day) or maintained normal cage activity. After each exercise bout, the peritendinous space of each Achilles tendon was injected with a TGF-β1receptor inhibitor or sham. Independent of group, tendons injected with inhibitor exhibited ~50% lower Smad 3 (Ser423/425) (P < 0.05) and 2.5-fold greater ERK1/2 phosphorylation (P < 0.05) when compared with sham (P < 0.05). Injection of the inhibitor did not alter collagen content in either group (P > 0.05). In exercised rats, hydroxylyslpyridinoline content and collagen III expression were lower (P < 0.05) in tendons injected with inhibitor when compared with sham. In nonexercised rats, collagen I and lysyl oxidase (LOX) expression was lower (P < 0.05) in tendons injected with inhibitor when compared with sham. Decorin expression was not altered by inhibitor in either group (P > 0.05). On the basis of evaluation of hematoxylin and eosin (H&E) stained cross sections, cell numbers were not altered by inhibitor treatment in either group (P > 0.05). Evaluation of H&E-stained sections revealed no effect of inhibitor on collagen fibril morphology. In contrast, scores for regional variation in cellularity decreased in exercised rats (P < 0.05). No differences in fiber arrangement, structure, and nuclei form were noted in either group (P > 0.05). Our findings suggest that TGF-β1signaling is necessary for the regulation of tendon cross-link formation, as well as collagen and LOX gene transcription in an exercise-dependent manner.

TidsskriftAmerican Journal of Physiology: Regulatory, Integrative and Comparative Physiology
Udgave nummer1
Sider (fra-til)R157-R164
StatusUdgivet - 2017

ID: 194039711