Unknown,Transcriptomics,Genomics,Proteomics

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Mechanical shear effects on flexor tendon cells

ABSTRACT: Adhesion formation after flexor tendon repair remains a clinical problem. Early postoperative motion after tendon repair has been demonstrated to reduce adhesion formation while increasing tendon strength. It is hypothesized that during mobilization, tendon cells experience mechanical shear forces that alter their biology in a fashion that reduces scar formation but also activates key genes involved in tendon healing. To test this hypothesis, primary intrinsic tenocyte cultures were established from flexor tendons of 20 Sprague-Dawley rats and sheared at 50 rpm (0.41 Pa) using a cone viscometer for 6 and 12 hours. Total RNA was harvested and compared with time-matched unsheared controls using cDNA microarrays and Northern blot analysis. Microarray analysis demonstrated that mechanical shear stress induced an overall "antifibrotic" expression pattern with decreased transcription of collagen type I and collagen type III. Shear stress down-regulated profibrotic molecules in the platelet-derived growth factor, insulin-like growth factor, and fibroblast growth factor signaling pathways. In addition, shear stress induced an overall decrease in transforming growth factor (TGF)-beta signaling pathway molecules with down-regulation of TGF-beta2, TGF-beta3, TGF-RI, and TGF-RII expression. Moreover, sheared tendon cells increased expression of matrix metalloproteinases and decreased expression of tissue inhibitors of metalloproteinase, an expression pattern consistent with an antifibrotic increase in extracellular matrix degradation. However, up-regulation of genes implicated in tendon healing, specifically, vascular endothelial growth factor-A and several bone morphogenetic proteins. Interestingly, the known mechanoresponsive gene, TGF-beta1, also implicated in tendon healing, was differentially up-regulated by shear stress. Northern blot validation of our results for TGF-beta1, TGF-beta2, TGF-beta3, and collagen type I demonstrated direct correlation with microarray data. Groups of assays that are related as part of a time series. Computed

ORGANISM(S): Mus musculus

SUBMITTER: Kenton Fong

PROVIDER: E-GEOD-4096 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Microarray analysis of mechanical shear effects on flexor tendon cells.

Fong Kenton D KD Trindade Michael C MC Wang Zhen Z Nacamuli Randall P RP Pham Hung H Fang Tony D TD Song Hanjoon M HM Smith R Lane RL Longaker Michael T MT Chang James J

Plastic and reconstructive surgery 20051001 5

<h4>Background</h4>Adhesion formation after flexor tendon repair remains a clinical problem. Early postoperative motion after tendon repair has been demonstrated to reduce adhesion formation while increasing tendon strength. The authors hypothesized that during mobilization, tendon cells experience mechanical shear forces that alter their biology in a fashion that reduces scar formation but also activates key genes involved in tendon healing.<h4>Methods</h4>To test this hypothesis, primary intri ...[more]

PMID: 16217485

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Mechanical shear effects on flexor tendon cells

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Microarray analysis of mechanical shear effects on flexor tendon cells.

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