title: The effects of enrofloxacin on canine tendon cells and chondrocytes proliferation in vitro.
abstract: Enrofloxacin, a fluoroquinolone antibiotic has been used widely in humans and domestic animals, including dogs, because of its broad-spectrum activity and relative safety. The side effects of fluoroquinolone, induced tendinopathy, tendonitis, spontaneous tendon rupture and cartilage damage, remain incompletely understood. In the present study, we investigated the in vitro effects of enrofloxacin on cell proliferation and induction of apoptosis in canine Achilles tendon cells and chondrocytes. Cell growth and proliferation after treating with enrofloxacin for 2-6 days was quantified by a colorimetric 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxyanilide inner salt (XTT) assay. The results showed that enrofloxacin could inhibit the proliferation of canine tendon cells and chondrocytes at increasing concentrations (10-200 microg/ml). The inhibition of proliferation of canine tendon cells and chondrocytes after exposure to enrofloxacin were associated with induction of apoptosis, as evidenced by the typical nuclear apoptotic condensed nuclei found using Hoechst 33258 staining. It was demonstrated that canine tendon cells and chondrocytes treated with 200 microg/ml enrofloxacin for 4 days exhibited apoptotic features and fragmentation of DNA. Enrofloxacin also increased the apoptosis of canine tendon cells and chondrocytes in a dose and time-dependent manner. The results indicate that enrofloxacin inhibits cell proliferation, induces apoptosis and DNA fragmentation, which might explain enrofloxacin-induced tendinopathy and cartilage damage.
authors.affiliation: Laboratory of Veterinary Surgery, College of Veterinary Medicine, Chungbuk National University, Cheongju 361-763, South Korea.
authors.forename: S
authors.initials: S
authors.lastname: Lim
authors.forename: M A
authors.initials: MA
authors.lastname: Hossain
authors.forename: J
authors.initials: J
authors.lastname: Park
authors.forename: S H
authors.initials: SH
authors.lastname: Choi
authors.forename: G
authors.initials: G
authors.lastname: Kim
mesh_terms: D000125:Achilles Tendon / Q000166:cytology / Q000187:drug effects; D000818:Animals; D000970:Antineoplastic Agents / Q000009:adverse effects / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D002357:Cartilage Diseases / Q000139:chemically induced / Q000662:veterinary*; D049109:Cell Proliferation / Q000187:drug effects; D019902:Chondrocytes / Q000166:cytology / Q000187:drug effects; D053938:DNA Fragmentation; D004283:Dog Diseases / Q000139:chemically induced*; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D000077422:Enrofloxacin; D024841:Fluoroquinolones / Q000009:adverse effects / Q000494:pharmacology*; D052256:Tendinopathy / Q000139:chemically induced / Q000662:veterinary*; D013997:Time Factors
chemical_list: D000970:Antineoplastic Agents; D024841:Fluoroquinolones; D000077422:Enrofloxacin