Mannose-6-phosphate, an inhibitor of transforming growth factor-beta, improves range of motion after flexor tendon repair JOURNAL OF BONE AND JOINT SURGERY-AMERICAN VOLUME Bates, S. J., Morrow, E., Zhang, A. Y., Pham, H., Longaker, M. T., Chang, J. 2006; 88A (11): 2465-2472

Abstract

Adhesion formation between the flexor tendon and its surrounding fibro-osseous sheath results in a decreased postoperative range of motion in the hand. Transforming growth factor-beta (TGF-beta) is a key cytokine in the pathogenesis of tissue fibrosis. In this study, the effects of two natural inhibitors of TGF-beta, decorin and mannose-6-phosphate, were investigated in vitro and in vivo.In the in vitro investigation, primary cell cultures from rabbit flexor tendon sheath, epitenon, and endotenon were established and each was supplemented with TGF-beta along with increasing doses of decorin or mannose-6-phosphate. Collagen-I production was measured with enzyme-linked immunosorbent assay (ELISA). For the in vivo study, rabbit zone-II flexor tendons were transected and then immediately repaired. Single intraoperative graded doses of decorin, mannose-6-phosphate, or phosphate-buffered saline solution (control) were added to the repair sites, and the forepaws were tested for the range of motion and repair strength at eight weeks postoperatively.Decorin and mannose-6-phosphate both reduced TGF-beta upregulated collagen production. Intraoperative application of low-dose mannose-6-phosphate significantly improved the range of motion of the operatively treated digits. The effect on breaking strength of the tendon repair was inconclusive.Mannose-6-phosphate is effective in reducing TGF-beta upregulated collagen production in an in vitro model. This finding correlated with our in vivo finding that a single intraoperative dose of mannose-6-phosphate improved the postoperative range of motion.

View details for DOI 10.2106/JBJS.E.00143

View details for Web of Science ID 000241769800020