title: ISSLS prize winner: LMP-1 upregulates intervertebral disc cell production of proteoglycans and BMPs in vitro and in vivo.
abstract: METHODS
  Experiments using both in vitro tissue culture and in vivo rabbit methods were used to study the effect of Lim Mineralization Protein-1 (LMP-1) on intervertebral disc (IVD) cell production of proteoglycans and bone morphogenetic proteins (BMPs).
  
  
  OBJECTIVE
  To determine the effect of LMP-1 overexpression in IVD cells on the production of proteoglycans and BMPs both in vitro and in vivo and to show that LMP-1 mediates the control of proteoglycan production through its action on BMPs.
  
  
  BACKGROUND
  Because BMPs are known to increase proteoglycan synthesis and LMP-1 is known to upregulate BMPs in certain cells, it was hypothesized that LMP-1 may increase proteoglycan production in IVD cells.
  
  
  METHODS
  DMMB, real-time polymerase chain reaction, and ELISA methods were used to quantitate proteoglycan, mRNA, and protein levels, respectively. Noggin was used to block the effect of the adenovirus carrying LMP-1 (AdLMP-1) on proteoglycan synthesis. In vivo experiments using intradiscal AdLMP-1 injection were performed with New Zealand White rabbits. Three weeks later, the mRNA levels of LMP-1, aggrecan, BMP-2, and BMP-7 were measured.
  
  
  RESULTS
  In vitro experiments revealed that the sulfated glycosaminoglycan (sGAG) and aggrecan mRNA levels were significantly increased with AdLMP-1 treatment. Similarly, BMP-2 and BMP-7 mRNA and protein levels increased significantly, but BMP-4 and BMP-6 levels were unchanged. Noggin blocked the upregulation of proteoglycan by AdLMP-1. In vivo discs injected with AdLMP-1 had significantly elevated levels of LMP-1, BMP-2, and BMP-7 mRNA.
  
  
  CONCLUSIONS
  LMP-1 overexpression increases disc cell production of proteoglycan, BMP-2, and BMP-7. LMP-1 mediates the control of proteoglycan production through its action on BMP.
authors.affiliation: Department of Orthopaedic Surgery, Emory University School of Medicine, Atlanta, GA, USA. tim_yoon@emoryhealthcare.org
authors.forename: Sangwook Tim
authors.initials: ST
authors.lastname: Yoon
authors.forename: Jin Soo
authors.initials: JS
authors.lastname: Park
authors.forename: Keun S
authors.initials: KS
authors.lastname: Kim
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.forename: Emad Samir
authors.initials: ES
authors.lastname: Attallah-Wasif
authors.forename: William C
authors.initials: WC
authors.lastname: Hutton
authors.forename: Scott D
authors.initials: SD
authors.lastname: Boden
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000256:Adenoviridae / Q000235:genetics; D053674:Aggrecans; D000818:Animals; D001363:Awards and Prizes; D055396:Bone Morphogenetic Protein 2; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins / Q000235:genetics / Q000378:metabolism*; D003598:Cytoskeletal Proteins; D004195:Disease Models, Animal; D016326:Extracellular Matrix Proteins / Q000235:genetics / Q000378:metabolism; D005822:Genetic Vectors; D006025:Glycosaminoglycans / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007403:Intervertebral Disc / Q000187:drug effects* / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism / Q000494:pharmacology*; D060588:LIM Domain Proteins; D037181:Lectins, C-Type / Q000235:genetics / Q000378:metabolism; D009985:Orthopedics; D011509:Proteoglycans / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D011817:Rabbits; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016212:Transforming Growth Factor beta / Q000235:genetics / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects
chemical_list: C508321:Acan protein, rat; D048868:Adaptor Proteins, Signal Transducing; D053674:Aggrecans; C525718:BMP2 protein, human; C525819:BMP7 protein, human; C525720:Bmp2 protein, rat; C525821:Bmp7 protein, rat; D055396:Bone Morphogenetic Protein 2; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins; D003598:Cytoskeletal Proteins; D016326:Extracellular Matrix Proteins; D006025:Glycosaminoglycans; D047908:Intracellular Signaling Peptides and Proteins; D060588:LIM Domain Proteins; D037181:Lectins, C-Type; C484380:PDLIM7 protein, human; D011509:Proteoglycans; D012333:RNA, Messenger; D016212:Transforming Growth Factor beta; C013786:A73025