title: Baicalein Inhibits MMPs Expression via a MAPK-Dependent Mechanism in Chondrocytes.
abstract: BACKGROUND
  Baicalein is a flavonoid isolated from Scutellaria baicalensis Georgi. Here, we investigated the anti-osteoarthritic effect of baicalein in vitro and in vivo.
  
  
  METHODS
  Interleukin-1 beta (IL-1β)-induced chondrocytes were treated with different concentrations of baicalein, real-time PCR and ELISA were performed to detect the matrix metalloproteinases (MMPs) expression. Western blot was used to evaluate the mitogen-activated protein kinase (MAPK) expression. In experimental osteoarthritis (OA), rabbits were treated with baicalein, gross morphological and histological assessment was performed to evaluate the cartilage damage.
  
  
  RESULTS
  Baicalein significantly reduced the expression of MMPs in vitro and in vivo. Moreover, baicalein significantly reduced the phosphorylation of p38 and extracellular signal regulated kinase (ERK), but not of c-Jun N-terminal kinase (JNK). In addition, intra-articular injection of baicalein ameliorated the cartilage damage in a rabbit model of OA induced by anterior cruciate ligament transection (ACLT).
  
  
  CONCLUSIONS
  The results indicate that baicalein may be considered as a potential agent for OA treatment.
authors.affiliation: Department of Orthopedic Surgery, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.
authors.forename: Wei-Ping
authors.initials: WP
authors.lastname: Chen
authors.forename: Yan
authors.initials: Y
authors.lastname: Xiong
authors.forename: Peng-Fei
authors.initials: PF
authors.lastname: Hu
authors.forename: Jia-Peng
authors.initials: JP
authors.lastname: Bao
authors.forename: Li-Dong
authors.initials: LD
authors.lastname: Wu
mesh_terms: D000368:Aged; D000818:Animals; D002478:Cells, Cultured; D019902:Chondrocytes / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D004195:Disease Models, Animal; D044950:Flavanones / Q000008:administration & dosage* / Q000494:pharmacology; D006801:Humans; D007270:Injections, Intra-Articular; D053583:Interleukin-1beta / Q000494:pharmacology; D020935:MAP Kinase Signaling System / Q000187:drug effects*; D020782:Matrix Metalloproteinases / Q000235:genetics / Q000378:metabolism*; D010003:Osteoarthritis / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D010766:Phosphorylation / Q000187:drug effects; D011817:Rabbits
chemical_list: D044950:Flavanones; D053583:Interleukin-1beta; C006680:baicalein; D020782:Matrix Metalloproteinases