Until the 1950's, the effect of physical stresses on the musculoskeletal system were not given rigorous attention. Along with heightened awareness of the dependence of the musculoskeletal system on mechanical stresses, came new development in internal fixation, which permitted a revolution in orthopedic and therapeutic strategies. A majority of studies have concentrated on the remodeling processes of tissues and it has been found that lack of mechanical stimulation have adverse effects on tissues. Although one can infer that the application of mechanical loads would possibly affect tissue remodeling processes, the actual mechanisms underlying the effects of mechanical stimulation on tissues are not yet fully understood. The goal of this proposal is to elucidate the molecular and cellular responses of anterior cruciate ligament (ACL) and medial collateral ligament (MCL) fibroblasts and ACL/MCL tissues to mechanical stimuli. These responses may be significantly affected by perturbations in mechanical stimulations. The long-term goals are to gain insights on methods to promote proper healing of the ACL and enhance the healing rate of the MCL, as well as to develop a reconstructed ligament that has similar functions as its pre-injury state. The applicant's hypothesis is that mechanical stimulation of ACL/MCL cells promote the maintenance of tissue integrity and strength by influencing gene expression and the deposition and destruction of matrix by ligament cells. The following four Specific Aims will be pursued to test this hypothesis: (1) to determine the effects of mechanical stimuli (amplitude and frequency) on specific cellular processes, including proliferation, apoptosis, integrin response, and in vitro wound recovery; (2) to elucidate how mechanical stimuli regulate mechanisms of anabolic (types I and III collagen and fibronectin) and catabolic (MMP-I, MMP-III, TIMP-I), gene expression by ligament fibroblasts cultured in monolayers; and (3) to investigate the effects of mechanical stimuli on expression of anabolic and catabolic genes by ligament fibroblasts and intact tissue (bone-ligament-bone preparations).

Agency
National Institute of Health (NIH)
Institute
National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
Type
Research Project (R01)
Project #
5R01AR045635-05
Application #
6774010
Study Section
Orthopedics and Musculoskeletal Study Section (ORTH)
Program Officer
Panagis, James S
Project Start
2000-07-07
Project End
2006-06-30
Budget Start
2004-07-01
Budget End
2006-06-30
Support Year
5
Fiscal Year
2004
Total Cost
$282,136
Indirect Cost
Name
University of California San Diego
Department
Engineering (All Types)
Type
Schools of Arts and Sciences
DUNS #
804355790
City
La Jolla
State
CA
Country
United States
Zip Code
92093
Zhang, Yanjun; Jiang, Jiahuan; Xie, Jing et al. (2017) Combined effects of tumor necrosis factor-? and interleukin-1? on lysyl oxidase and matrix metalloproteinase expression in human knee synovial fibroblasts in vitro. Exp Ther Med 14:5258-5266
Wang, Chunli; Xie, Jing; Jiang, Jiahuan et al. (2015) Differential expressions of the lysyl oxidase family and matrix metalloproteinases-1, 2, 3 in posterior cruciate ligament fibroblasts after being co-cultured with synovial cells. Int Orthop 39:183-91
Zhang, Yanjun; Huang, Wei; Jiang, Jiahuang et al. (2014) Influence of TNF-? and biomechanical stress on matrix metalloproteinases and lysyl oxidases expressions in human knee synovial fibroblasts. Knee Surg Sports Traumatol Arthrosc 22:1997-2006
Xie, Jing; Jiang, Jiahuan; Huang, Wei et al. (2014) TNF-? induced down-regulation of lysyl oxidase family in anterior cruciate ligament and medial collateral ligament fibroblasts. Knee 21:47-53
Xie, Jing; Huang, Wei; Jiang, Jiahuan et al. (2013) Differential expressions of lysyl oxidase family in ACL and MCL fibroblasts after mechanical injury. Injury 44:893-900
Xie, Jing; Wang, Chunli; Yin, Lin et al. (2013) Interleukin-1 beta influences on lysyl oxidases and matrix metalloproteinases profile of injured anterior cruciate ligament and medial collateral ligament fibroblasts. Int Orthop 37:495-505
Xie, Jing; Jiang, Jiahuan; Zhang, Yanjun et al. (2012) Up-regulation expressions of lysyl oxidase family in Anterior Cruciate Ligament and Medial Collateral Ligament fibroblasts induced by Transforming Growth Factor-Beta 1. Int Orthop 36:207-13
Xue, Ruyue; Yang, Li; Tang, Zhenyu et al. (2010) The profile of MMP and TIMP in injured rat ACL. Mol Cell Biomech 7:115-24
Wang, Yequan; Yang, Li; Zhang, Jin et al. (2010) Differential MMP-2 activity induced by mechanical compression and inflammatory factors in human synoviocytes. Mol Cell Biomech 7:105-14
Zhang, Jin; Yang, Li; Tang, Zhenyu et al. (2009) Expression of MMPs and TIMPs family in human ACL and MCL fibroblasts. Connect Tissue Res 50:7-13

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