Effects of crystalline glucocorticoid triamcinolone acetonide on cultered human supraspinatus tendon cells.
BACKGROUND
Rotator cuff tears are a common cause of shoulder pain and impairment. Subacromial glucocorticoid injections are widely used for treatment of epiphenomenons of chronic impingement syndrome with the possible side effects of tendon rupture and impaired tendon healing.


METHODS
Using qRT-PCR, western blot, immunoflourescence, and measurement of 3H-thymidine uptake we investigated the effects of the crystalline glucocorticoid triamcinolone acetonide (TAA) when added to the culture medium of isolated human rotator cuff tendon cells.


RESULTS
After 2 weeks of incubation, the cells had lost their fibroblastic appearance and parallel orientation, which is characteristic of cellular degeneration in vivo. Moreover, expression and secretion of collagen I was strongly reduced, and there was a decrease in proliferation rate. Cell migration was blocked and the rate of expression of the matrix metalloproteinases MMP2, MMP8, MMP9, and MMP13 was reduced, but expression of TIMP1 (a tissue inhibitor of MMPs) was upregulated, indicating a reduction in the cellular capacity for tendon repair. In addition, changes in cellular differentiation were observed: the number of adipocytes increased and levels of the protein Sox9-a marker of differentiating and mature chondrocytes-were elevated in triamcinolone acetonide treated cells.


CONCLUSIONS
These results may indicate that the use of TAA is one reason for weaker mechanical tendon properties and for the high rate of re-rupture after supraspinatus tendon repair.
Tempfer
Herbert
H
Department of Organismic Biology, Division of Zoology and Functional Anatomy, University of Salzburg, Austria. Herbert.Tempfer@sbg.ac.at
Gehwolf
Renate
R
Lehner
Christine
C
Wagner
Andrea
A
Mtsariashvili
Maia
M
Bauer
Hans-Christian
HC
Resch
Herbert
H
Tauber
Mark
M
D000293:Adolescent; D000328:Adult; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D003094:Collagen / Q000096:biosynthesis / Q000378:metabolism; D005260:Female; D005938:Glucocorticoids / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D006801:Humans; D008297:Male; D020782:Matrix Metalloproteinases / Q000378:metabolism; D008875:Middle Aged; D017006:Rotator Cuff / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D013710:Tendons / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D014221:Triamcinolone / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D055815:Young Adult
D000893:Anti-Inflammatory Agents; D005938:Glucocorticoids; D014221:Triamcinolone; D003094:Collagen; D020782:Matrix Metalloproteinases