Peroxisome proliferator--activated receptor gamma activators inhibit interleukin-1beta-induced nitric oxide and matrix metalloproteinase 13 production in human chondrocytes

Arthritis Rheum. 2001 Mar;44(3):595-607. doi: 10.1002/1529-0131(200103)44:3<595::AID-ANR108>3.0.CO;2-8.


Objective: To determine the effects of peroxisome proliferator-activated receptor gamma (PPARgamma) agonists on interleukin-1 (IL-1) induction of nitric oxide (NO) and matrix metalloproteinase 13 (MMP-13) in human chondrocytes.

Methods: PPARgamma expression and synthesis in human chondrocytes were determined by reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemistry, respectively. Chondrocytes were cultured with IL-1beta, tumor necrosis factor alpha (TNFalpha), and IL-17 in the presence or absence of PPARgamma agonists, and NO and MMP-13 synthesis and expression levels were measured. Transient transfection experiments were performed with the 7-kb inducible NO synthase (iNOS) and 1.6-kb MMP-13 human promoters, as well as with the PPARgamma expression vector and the activator protein 1 (AP-1) and nuclear factor kappaB (NF-kappaB) reporter constructs.

Results: RT-PCR and immunohistochemical analysis revealed that human chondrocytes expressed and produced PPARgamma. Treatment of chondrocytes with PPARgamma ligands BRL 49653 and 15-deoxy-delta12,14-prostaglandin J2 (15d-PGJ2), but not with PPARalpha ligand Wy 14643, decreased IL-1beta-induced NO and MMP-13 production in a dose-dependent manner. In addition, both iNOS and MMP-13 messenger RNA were inhibited in the presence of 15d-PGJ2. The inhibitory effect of PPARgamma activation was not restricted to IL-1beta, since TNFalpha- and IL-17-induced NO and MMP-13 production were also inhibited by 15d-PGJ2. In transient transfection experiments, we showed that a constitutively active form of mitogen-activated protein kinase kinase kinase 1 (AMEKK-1) induced the MMP-13 and iNOS human promoter activity. This process was reduced by 15d-PGJ2 and further inhibited by cotransfection with a PPARgamma expression vector. Similarly, in a PPARgamma-dependent manner, 15d-PGJ2 inhibited deltaMEKK-1-induced AP-1- and NF-kappaB-luciferase reporter plasmid activation.

Conclusion: The findings of this study demonstrate that PPARgamma agonists inhibit IL-1beta induction of both NO and MMP-13 in human chondrocytes. The inhibition occurs at least at the transcriptional level through a PPARgamma-dependent pathway, probably by interfering with the activation of AP-1 and NF-kappaB.

MeSH terms

  • Chondrocytes / metabolism*
  • Collagenases / biosynthesis*
  • Enzyme Activation / genetics
  • Humans
  • Interleukin-1 / antagonists & inhibitors*
  • MAP Kinase Kinase Kinase 1*
  • Matrix Metalloproteinase 13
  • NF-kappa B / antagonists & inhibitors
  • Nitric Oxide / metabolism*
  • Nitric Oxide Synthase / antagonists & inhibitors
  • Nitric Oxide Synthase / genetics
  • Nitric Oxide Synthase Type II
  • Promoter Regions, Genetic / drug effects
  • Prostaglandin D2 / analogs & derivatives*
  • Prostaglandin D2 / pharmacology
  • Protein-Serine-Threonine Kinases / physiology
  • RNA, Messenger / metabolism
  • Receptors, Cytoplasmic and Nuclear / agonists*
  • Receptors, Cytoplasmic and Nuclear / genetics
  • Transcription Factor AP-1 / antagonists & inhibitors
  • Transcription Factors / agonists*
  • Transcription Factors / genetics
  • Transcription Factors / pharmacology
  • Transcription, Genetic / drug effects


  • Interleukin-1
  • NF-kappa B
  • RNA, Messenger
  • Receptors, Cytoplasmic and Nuclear
  • Transcription Factor AP-1
  • Transcription Factors
  • Nitric Oxide
  • 9-deoxy-delta-9-prostaglandin D2
  • NOS2 protein, human
  • Nitric Oxide Synthase
  • Nitric Oxide Synthase Type II
  • Protein-Serine-Threonine Kinases
  • MAP Kinase Kinase Kinase 1
  • MAP3K1 protein, human
  • Collagenases
  • MMP13 protein, human
  • Matrix Metalloproteinase 13
  • Prostaglandin D2