Effects of stress deprivation on lubricin synthesis and gliding of flexor tendons in a canine model in vivo

Yu Long Sun, Chunfeng D Zhao, Gregory D. Jay, Thomas M. Schmid, Kai Nan An, Peter C Amadio

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

Background: Lubricin facilitates boundary lubrication of cartilage. The synthesis of lubricin in cartilage is regulated by mechanical stimuli, especially shear force. Lubricin is also found in flexor tendons. However, little is known about the effect of mechanical loading on lubricin synthesis in tendons or about the function of lubricin in flexor tendons. The purpose of this study was to investigate the relationship of mechanical loading to lubricin expression and gliding resistance of flexor tendons. Methods: Flexor tendons were harvested from canine forepaws that had been suspended without weight-bearing for twenty-one days and from the contralateral forepaws that had been allowed free motion. Lubricin expression in each flexor tendon was investigated with real-time RT-PCR (reverse transcription polymerase chain reaction) and immunohistochemistry. Lubricin in the flexor tendon was extracted and quantified with ELISA (enzyme-linked immunosorbent assay). The friction between the flexor tendon and the proximal pulley was measured. Results: The non-weight-bearing flexor tendons had a 40% reduction of lubricin expression (p < 0.01) and content (p < 0.01) compared with the flexor tendons in the contralateral limb. However, the gliding resistance of the tendons in the nonweight- bearing limb was the same as that of the tendons on the contralateral, weight-bearing side. Conclusions: Mechanical loading affected lubricin expression in flexor tendons, resulting in a 40% reduction of lubricin content, but these changes did not affect the gliding resistance of the flexor tendons. Clinical Relevance: The gliding resistance of flexor tendons was not affected after a period of limited motion. This suggests that physical activity after a short period of limited motion does not lead to wear of intact tendons and their surrounding tissue. COPYRIGHT

Original languageEnglish (US)
Pages (from-to)273-278
Number of pages6
JournalJournal of Bone and Joint Surgery - Series A
Volume95
Issue number3
DOIs
StatePublished - Feb 6 2013

Fingerprint

Tendons
Canidae
lubricin
Weight-Bearing
Cartilage
Extremities
Lubrication
Friction
Reverse Transcription

ASJC Scopus subject areas

  • Surgery
  • Orthopedics and Sports Medicine

Cite this

Effects of stress deprivation on lubricin synthesis and gliding of flexor tendons in a canine model in vivo. / Sun, Yu Long; Zhao, Chunfeng D; Jay, Gregory D.; Schmid, Thomas M.; An, Kai Nan; Amadio, Peter C.

In: Journal of Bone and Joint Surgery - Series A, Vol. 95, No. 3, 06.02.2013, p. 273-278.

Research output: Contribution to journalArticle

@article{706b552af9724472864b57b2f4307f51,
title = "Effects of stress deprivation on lubricin synthesis and gliding of flexor tendons in a canine model in vivo",
abstract = "Background: Lubricin facilitates boundary lubrication of cartilage. The synthesis of lubricin in cartilage is regulated by mechanical stimuli, especially shear force. Lubricin is also found in flexor tendons. However, little is known about the effect of mechanical loading on lubricin synthesis in tendons or about the function of lubricin in flexor tendons. The purpose of this study was to investigate the relationship of mechanical loading to lubricin expression and gliding resistance of flexor tendons. Methods: Flexor tendons were harvested from canine forepaws that had been suspended without weight-bearing for twenty-one days and from the contralateral forepaws that had been allowed free motion. Lubricin expression in each flexor tendon was investigated with real-time RT-PCR (reverse transcription polymerase chain reaction) and immunohistochemistry. Lubricin in the flexor tendon was extracted and quantified with ELISA (enzyme-linked immunosorbent assay). The friction between the flexor tendon and the proximal pulley was measured. Results: The non-weight-bearing flexor tendons had a 40{\%} reduction of lubricin expression (p < 0.01) and content (p < 0.01) compared with the flexor tendons in the contralateral limb. However, the gliding resistance of the tendons in the nonweight- bearing limb was the same as that of the tendons on the contralateral, weight-bearing side. Conclusions: Mechanical loading affected lubricin expression in flexor tendons, resulting in a 40{\%} reduction of lubricin content, but these changes did not affect the gliding resistance of the flexor tendons. Clinical Relevance: The gliding resistance of flexor tendons was not affected after a period of limited motion. This suggests that physical activity after a short period of limited motion does not lead to wear of intact tendons and their surrounding tissue. COPYRIGHT",
author = "Sun, {Yu Long} and Zhao, {Chunfeng D} and Jay, {Gregory D.} and Schmid, {Thomas M.} and An, {Kai Nan} and Amadio, {Peter C}",
year = "2013",
month = "2",
day = "6",
doi = "10.2106/JBJS.K.01522",
language = "English (US)",
volume = "95",
pages = "273--278",
journal = "Journal of Bone and Joint Surgery - American Volume",
issn = "0021-9355",
publisher = "Journal of Bone and Joint Surgery Inc.",
number = "3",

}

TY - JOUR

T1 - Effects of stress deprivation on lubricin synthesis and gliding of flexor tendons in a canine model in vivo

AU - Sun, Yu Long

AU - Zhao, Chunfeng D

AU - Jay, Gregory D.

AU - Schmid, Thomas M.

AU - An, Kai Nan

AU - Amadio, Peter C

PY - 2013/2/6

Y1 - 2013/2/6

N2 - Background: Lubricin facilitates boundary lubrication of cartilage. The synthesis of lubricin in cartilage is regulated by mechanical stimuli, especially shear force. Lubricin is also found in flexor tendons. However, little is known about the effect of mechanical loading on lubricin synthesis in tendons or about the function of lubricin in flexor tendons. The purpose of this study was to investigate the relationship of mechanical loading to lubricin expression and gliding resistance of flexor tendons. Methods: Flexor tendons were harvested from canine forepaws that had been suspended without weight-bearing for twenty-one days and from the contralateral forepaws that had been allowed free motion. Lubricin expression in each flexor tendon was investigated with real-time RT-PCR (reverse transcription polymerase chain reaction) and immunohistochemistry. Lubricin in the flexor tendon was extracted and quantified with ELISA (enzyme-linked immunosorbent assay). The friction between the flexor tendon and the proximal pulley was measured. Results: The non-weight-bearing flexor tendons had a 40% reduction of lubricin expression (p < 0.01) and content (p < 0.01) compared with the flexor tendons in the contralateral limb. However, the gliding resistance of the tendons in the nonweight- bearing limb was the same as that of the tendons on the contralateral, weight-bearing side. Conclusions: Mechanical loading affected lubricin expression in flexor tendons, resulting in a 40% reduction of lubricin content, but these changes did not affect the gliding resistance of the flexor tendons. Clinical Relevance: The gliding resistance of flexor tendons was not affected after a period of limited motion. This suggests that physical activity after a short period of limited motion does not lead to wear of intact tendons and their surrounding tissue. COPYRIGHT

AB - Background: Lubricin facilitates boundary lubrication of cartilage. The synthesis of lubricin in cartilage is regulated by mechanical stimuli, especially shear force. Lubricin is also found in flexor tendons. However, little is known about the effect of mechanical loading on lubricin synthesis in tendons or about the function of lubricin in flexor tendons. The purpose of this study was to investigate the relationship of mechanical loading to lubricin expression and gliding resistance of flexor tendons. Methods: Flexor tendons were harvested from canine forepaws that had been suspended without weight-bearing for twenty-one days and from the contralateral forepaws that had been allowed free motion. Lubricin expression in each flexor tendon was investigated with real-time RT-PCR (reverse transcription polymerase chain reaction) and immunohistochemistry. Lubricin in the flexor tendon was extracted and quantified with ELISA (enzyme-linked immunosorbent assay). The friction between the flexor tendon and the proximal pulley was measured. Results: The non-weight-bearing flexor tendons had a 40% reduction of lubricin expression (p < 0.01) and content (p < 0.01) compared with the flexor tendons in the contralateral limb. However, the gliding resistance of the tendons in the nonweight- bearing limb was the same as that of the tendons on the contralateral, weight-bearing side. Conclusions: Mechanical loading affected lubricin expression in flexor tendons, resulting in a 40% reduction of lubricin content, but these changes did not affect the gliding resistance of the flexor tendons. Clinical Relevance: The gliding resistance of flexor tendons was not affected after a period of limited motion. This suggests that physical activity after a short period of limited motion does not lead to wear of intact tendons and their surrounding tissue. COPYRIGHT

UR - http://www.scopus.com/inward/record.url?scp=84873915996&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84873915996&partnerID=8YFLogxK

U2 - 10.2106/JBJS.K.01522

DO - 10.2106/JBJS.K.01522

M3 - Article

C2 - 23389791

AN - SCOPUS:84873915996

VL - 95

SP - 273

EP - 278

JO - Journal of Bone and Joint Surgery - American Volume

JF - Journal of Bone and Joint Surgery - American Volume

SN - 0021-9355

IS - 3

ER -