title: Ciprofloxacin up-regulates tendon cells to express matrix metalloproteinase-2 with degradation of type I collagen.
abstract: Ciprofloxacin-induced tendinopathy and tendon rupture have been previously described, principally affecting the Achilles tendon. This study was designed to investigate the effect of ciprofloxacin on expressions of matrix metalloproteinases (MMP)-2 and -9, tissue inhibitors of metalloproteinase (TIMP)-1 and -2 as well as type I collagen in tendon cells. Tendon cells intrinsic to rat Achilles tendon were treated with ciprofloxacin and then underwent MTT (tetrazolium) assay. Real-time reverse-transcription polymerase chain reaction (RT-PCR) and Western blot analysis were used, respectively, to evaluate the gene and protein expressions of type I collagen, and MMP-2. Gelatin zymography was used to evaluate the enzymatic activities of MMP-2 and -9. Reverse zymography was used to evaluate TIMP-1 and -2. Immunohistochemical staining for MMP-2 in ciprofloxacin-treated tendon explants was performed. Collagen degradation was evaluated by incubation of conditioned medium with collagen. The results revealed that ciprofloxacin up-regulated the expression of MMP-2 in tendon cells at the mRNA and protein levels. Immunohistochemistry also confirmed the increased expressions of MMP-2 in ciprofloxacin-treated tendon explants. The enzymatic activity of MMP-2 was up-regulated whereas that of MMP-9, TIMP-1 or TIMP-2 was unchanged. The amount of secreted type I collagen in the conditioned medium decreased and type I collagen was degraded after ciprofloxacin treatment. In conclusion, ciprofloxacin up-regulates the expressions of MMP-2 in tendon cells and thus degraded type I collagen. These findings suggest a possible mechanism of ciprofloxacin-associated tendinopathy.
authors.affiliation: Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital at Linkou, College of Medicine, Chang Gung University, Linkou, Taiwan.
authors.forename: Wen-Chung
authors.initials: WC
authors.lastname: Tsai
authors.forename: Chih-Chin
authors.initials: CC
authors.lastname: Hsu
authors.forename: Carl P C
authors.initials: CP
authors.lastname: Chen
authors.forename: Hsiang-Ning
authors.initials: HN
authors.lastname: Chang
authors.forename: Alice M K
authors.initials: AM
authors.lastname: Wong
authors.forename: Miao-Sui
authors.initials: MS
authors.lastname: Lin
authors.forename: Jong-Hwei S
authors.initials: JH
authors.lastname: Pang
mesh_terms: D000125:Achilles Tendon / Q000187:drug effects* / Q000378:metabolism; D000818:Animals; D000890:Anti-Infective Agents / Q000633:toxicity*; D002470:Cell Survival / Q000187:drug effects; D002939:Ciprofloxacin / Q000633:toxicity*; D024042:Collagen Type I / Q000235:genetics / Q000378:metabolism*; D020778:Matrix Metalloproteinase 2 / Q000032:analysis / Q000235:genetics*; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000032:analysis; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000032:analysis; D015854:Up-Regulation
chemical_list: D000890:Anti-Infective Agents; D024042:Collagen Type I; D019715:Tissue Inhibitor of Metalloproteinase-1; D019716:Tissue Inhibitor of Metalloproteinase-2; D002939:Ciprofloxacin; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9