title: Systemic hypoxia alters gene expression levels of structural proteins and growth factors in knee joint cartilage.
abstract: We investigated the effects of short- (8- and 24-h) and long-term (3 weeks) exposure to systemic normobaric hypoxia (13%) on the gene expression level of structural proteins and growth factors in knee joint cartilage of rabbits. Collagen type Ia2, II, and Va1, TGF-beta1, and b-FGF were upregulated after short-term hypoxia in both menisci, but not in articular cartilage. In contrast, long-term hypoxia downregulated gene expression level of collagens, aggrecan, and growth factors in articular cartilage and meniscal fibrocartilage. Interestingly, gene expression levels of non-collagenous proteins biglycan, decorin, and versican were not affected by short-term or by long-term hypoxia in knee joint cartilage. The present study suggests that changes in oxygen level differentially affect gene expression levels of growth factors, collagens, and non-collagenous proteins in normal knee joint cartilage in rabbits.
authors.affiliation: Laboratory for Skeletal Disorders and Rehabilitation, Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02215, USA. Jochen.Hofstaetter@childrens.harvard.edu
authors.forename: Jochen G
authors.initials: JG
authors.lastname: Hofstaetter
authors.forename: Livius
authors.initials: L
authors.lastname: Wunderlich
authors.forename: Raymond E
authors.initials: RE
authors.lastname: Samuel
authors.forename: Fawzy A
authors.initials: FA
authors.lastname: Saad
authors.forename: Yeong-Hoon
authors.initials: YH
authors.lastname: Choi
authors.forename: Melvin J
authors.initials: MJ
authors.lastname: Glimcher
mesh_terms: D053674:Aggrecans; D000818:Animals; D001483:Base Sequence; D002358:Cartilage, Articular / Q000378:metabolism*; D003094:Collagen / Q000235:genetics*; D017931:DNA Primers; D016326:Extracellular Matrix Proteins / Q000235:genetics*; D005786:Gene Expression Regulation; D006133:Growth Substances / Q000235:genetics*; D000860:Hypoxia / Q000235:genetics*; D007719:Knee Joint / Q000378:metabolism*; D037181:Lectins, C-Type; D011509:Proteoglycans / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011817:Rabbits; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D053674:Aggrecans; D017931:DNA Primers; D016326:Extracellular Matrix Proteins; D006133:Growth Substances; D037181:Lectins, C-Type; D011509:Proteoglycans; D012333:RNA, Messenger; D003094:Collagen