title: Jellyfish mucin may have potential disease-modifying effects on osteoarthritis.
abstract: BACKGROUND
  We aimed to study the effects of intra-articular injection of jellyfish mucin (qniumucin) on articular cartilage degeneration in a model of osteoarthritis (OA) created in rabbit knees by resection of the anterior cruciate ligament. Qniumucin was extracted from Aurelia aurita (moon jellyfish) and Stomolophus nomurai (Nomura's jellyfish) and purified by ion exchange chromatography. The OA model used 36 knees in 18 Japanese white rabbits. Purified qniumucin extracts from S. nomurai or A. aurita were used at 1 mg/ml. Rabbits were divided into four groups: a control (C) group injected with saline; a hyaluronic acid (HA)-only group (H group); two qniumucin-only groups (M groups); and two qniumucin + HA groups (MH groups). One milligram of each solution was injected intra-articularly once a week for 5 consecutive weeks, starting from 4 weeks after surgery. Ten weeks after surgery, the articular cartilage was evaluated macroscopically and histologically.
  
  
  RESULTS
  In the C and M groups, macroscopic cartilage defects extended to the subchondral bone medially and laterally. When the H and both MH groups were compared, only minor cartilage degeneration was observed in groups treated with qniumucin in contrast to the group without qniumucin. Histologically, densely safranin-O-stained cartilage layers were observed in the H and two MH groups, but cartilage was strongly maintained in both MH groups.
  
  
  CONCLUSIONS
  At the concentrations of qniumucin used in this study, injection together with HA inhibited articular cartilage degeneration in this model of OA.
authors.affiliation: Department of Orthopaedic Surgery, Surgical Science, Tokai University School of Medicine, Isehara, Kanagawa, Japan. naoshi-o@is.icc.u-tokai.ac.jp
authors.forename: Naoshi
authors.initials: N
authors.lastname: Ohta
authors.forename: Masato
authors.initials: M
authors.lastname: Sato
authors.forename: Kiminori
authors.initials: K
authors.lastname: Ushida
authors.forename: Mami
authors.initials: M
authors.lastname: Kokubo
authors.forename: Takayuki
authors.initials: T
authors.lastname: Baba
authors.forename: Kayoko
authors.initials: K
authors.lastname: Taniguchi
authors.forename: Makoto
authors.initials: M
authors.lastname: Urai
authors.forename: Koji
authors.initials: K
authors.lastname: Kihira
authors.forename: Joji
authors.initials: J
authors.lastname: Mochida
mesh_terms: D000818:Animals; D000070598:Anterior Cruciate Ligament Injuries; D002358:Cartilage, Articular / Q000187:drug effects / Q000473:pathology; D004195:Disease Models, Animal; D005260:Female; D006820:Hyaluronic Acid / Q000494:pharmacology; D007270:Injections, Intra-Articular; D009077:Mucins / Q000494:pharmacology*; D020370:Osteoarthritis, Knee / Q000188:drug therapy*; D011817:Rabbits; D037401:Scyphozoa / Q000737:chemistry*
chemical_list: D009077:Mucins; C522139:qniumucin; D006820:Hyaluronic Acid