We characterized the effect of ciprofloxacin (CPX) in cultured human tenocytes by morphological and molecular methods. Collagen type I and III mRNA and protein levels were unaffected, but lysyl hydroxylase 2b mRNA levels progressively decreased after CPX administration. MMP- 1 protein levels significantly increased after 20 μg/ml CPX administration but remained unmodified at the higher dose, whilst MMP-2 activity was unchanged. Tissue inhibitor of MMP (TIMP- 1) gene expression decreased after CPX treatment, whilst TIMP-2 and transforming growth factor-β1 gene expression, the cytoskeleton arrangement, and cytochrome c expression remained unmodified. Secreted Protein Acidic and Rich in Cysteine mRNA and protein levels remained almost unchanged, whilst N-cadherin mRNA levels resulted significantly down-regulated and connexin 43 gene expression tended to decrease after CPX administration. The CPX-induced decreased ability to cross-link collagen and decreased TIMP-1 levels, possibly leading to higher activity of MMPs in ECM degradation, together with the down-regulation of Ncadherin and connexin 43 are consistent with a reduced ability to maintain tissue homeostasis, possibly making the tendon more susceptible to rupture.
- Collagen turnover
- Extracellular matrix remodelling
ASJC Scopus subject areas
- Orthopedics and Sports Medicine