Expression of transforming growth factor beta isoforms and their roles in tendon healing.
Transforming growth factor beta (TGF-beta) plays active roles in tendon healing. However, the differential effects of TGF-beta isoforms on tendon healing have not been investigated. In cultured tendon fibroblasts, we tested the effects of TGF-beta1, beta2, and beta3 on the mRNA levels of COL1A1 and COL3A1 by quantitative real-time polymerase chain reaction. We also investigated the expression of TGF-beta isoforms, TGF-beta receptors, procollagen Type I and Type III in a rat model of tendon healing. We found that TGF-beta3 exhibited the highest potency in stimulating COL1A1 and COL3A1. TGF-beta1 exerted antagonistic effects to TGF-beta2 and beta3. All TGF-beta isoforms and procollagen Type I were confined to the edges of the healing tendon at day 28 postinjury. Our results indicated that interaction of TGF-beta isoforms exist in the regulation of collagen synthesis in tendon fibroblasts. Their effects may be further complicated by uneven spatial distribution of TGF-beta and TGF-beta receptors in healing tendons.
Chan
Kai-Ming
KM
Department of Orthopaedics & Traumatology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong. kaimingchan@cuhk.edu.hk
Fu
Sai-Chuen
SC
Wong
Yim-Ping
YP
Hui
Wun-Chun
WC
Cheuk
Yau-Chuk
YC
Wong
Margaret Wan-Nar
MW
D000818:Animals; D002478:Cells, Cultured; D024042:Collagen Type I / Q000235:genetics*; D000090602:Collagen Type I, alpha 1 Chain; D024061:Collagen Type III / Q000235:genetics*; D004195:Disease Models, Animal; D015870:Gene Expression; D016133:Polymerase Chain Reaction; D020033:Protein Isoforms / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D018125:Receptors, Transforming Growth Factor beta / Q000378:metabolism; D013708:Tendon Injuries / Q000503:physiopathology*; D014018:Tissue Distribution; D016212:Transforming Growth Factor beta / Q000378:metabolism*; D014945:Wound Healing / Q000502:physiology*
D024042:Collagen Type I; D000090602:Collagen Type I, alpha 1 Chain; D024061:Collagen Type III; D020033:Protein Isoforms; D012333:RNA, Messenger; D018125:Receptors, Transforming Growth Factor beta; D016212:Transforming Growth Factor beta