title: Triamcinolone suppresses human tenocyte cellular activity and collagen synthesis.
abstract: Glucocorticoid injection is widely used in tendon disorders. Despite previous studies on the histologic and biomechanical changes in tendons after glucocorticoid injections, the role of glucocorticoid in tendon rupture still is controversial. It was hypothesized that glucocorticoid has a direct deleterious effect on human tenocytes, suppressing its cellular activity and collagen production. Primary cultures of human tenocytes were obtained from explants of healthy patellar tendon harvested during anterior cruciate ligament reconstructions. The effects on cell viability and cell proliferation were measured by [3-(4,5-demethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay and 5-bromo-deoxyuridine incorporations. The effect on collagen synthesis was measured by H-proline incorporation assay. Triamcinolone acetonide at 10 to 10 mol/L decreased human tenocyte viability to 45% to 88% of control in a dose-dependent manner. Cell proliferation was suppressed to 87% +/- 8% at all doses. Treatment with 1 micromol/L triamcinolone acetonide reduced the amount of collagen synthesis as measured by H-proline incorporation from 40 +/- 2 cpm/1000 cells to 27 +/- 4 cpm/1000 cells. The suppressed human tenocyte cellular activity and reduced collagen production may lead to disturbed tendon structure and predispose the tendon to subsequent spontaneous rupture.
authors.affiliation: Department of Orthopaedics and Traumatology, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong. mwnwong@cuhk.edu.hk
authors.forename: Margaret Wan Nar
authors.initials: MW
authors.lastname: Wong
authors.forename: Yin Nei
authors.initials: YN
authors.lastname: Tang
authors.forename: Sai Chuen
authors.initials: SC
authors.lastname: Fu
authors.forename: Kwong Man
authors.initials: KM
authors.lastname: Lee
authors.forename: Kai Ming
authors.initials: KM
authors.lastname: Chan
mesh_terms: D018929:Cell Culture Techniques; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D003094:Collagen / Q000096:biosynthesis*; D005938:Glucocorticoids / Q000494:pharmacology*; D006801:Humans; D013710:Tendons / Q000166:cytology* / Q000187:drug effects* / Q000378:metabolism; D014222:Triamcinolone Acetonide / Q000494:pharmacology*
chemical_list: D005938:Glucocorticoids; D003094:Collagen; D014222:Triamcinolone Acetonide