Rhein, a diacerhein-derived metabolite, modulates the expression of matrix degrading enzymes and the cell proliferation of articular chondrocytes by inhibiting ERK and JNK-AP-1 dependent pathways.
OBJECTIVE
To determine the effects of rhein on the expression of matrix metalloproteinases (MMP-1, -3, 13) and ADAMTs 4, 5 (a disintegrin and metalloproteinase with thrombospondin type-I repeat)/aggrecanases-1, -2 in interleukin-1-stimulated bovine articular chondrocytes, and to investigate the signalling pathways involved in the effects of the drug on gene expression and cell proliferation.


METHODS
Bovine chondrocytes were treated with 10(-4) M rhein for 18 h, followed by 10 ng/ml IL-1Beta for 30 min (cytoplasmic extracts) or 24 h (RNA extraction and EMSA). mRNA was assessed by RT-PCR for the expression of MMPs and aggrecanases, and the phosphorylation of MAP kinases was studied by Western blotting. NF-kappaB and AP-1 DNA binding were determined by gel retardation assay. The effects of inhibitors of these signalling pathways were compared to those of rhein. The proliferation of human chondrocytes and synoviocytes treated with the drug was also investigated.


RESULTS
IL-1Beta-induced stimulation of the MMPs and aggrecanase-1 was markedly inhibited by rhein. The drug reduced IL-1Beta-induced NF-kappaB and AP-1 DNA binding, as well as the phosphorylation of ERK and JNK. Similar effects were produced by the specific inhibitors of these signalling pathways. In addition, rhein reduced the proliferation of both human chondrocytes and synoviocytes.


CONCLUSIONS
Our data indicate that rhein may reduce the deleterious effects of IL-1Beta on osteoarthritic cartilage through its effects on the ERK- and JNK-dependent pathways. Both its anti-catabolic and anti-proliferative properties may explain its value in the treatment of joint diseases.
Legendre
F
F
Laboratory of Connective Tissue Biochemistry, Faculty of Medicine, Caen, France.
Bogdanowicz
P
P
Martin
G
G
Domagala
F
F
Leclercq
S
S
Pujol
J-P
JP
Ficheux
H
H
D051722:ADAM Proteins / Q000037:antagonists & inhibitors*; D000071121:ADAMTS4 Protein; D000071116:ADAMTS5 Protein; D000818:Animals; D000880:Anthraquinones / Q000494:pharmacology*; D002358:Cartilage, Articular / Q000166:cytology; D002417:Cattle; D049109:Cell Proliferation / Q000187:drug effects*; D002478:Cells, Cultured; D019902:Chondrocytes / Q000166:cytology / Q000187:drug effects*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D048049:Extracellular Signal-Regulated MAP Kinases / Q000502:physiology; D007375:Interleukin-1 / Q000494:pharmacology; D048670:MAP Kinase Kinase 4 / Q000502:physiology*; D061965:Matrix Metalloproteinase Inhibitors; D045726:Metalloproteases / Q000037:antagonists & inhibitors*; D011348:Procollagen N-Endopeptidase / Q000037:antagonists & inhibitors*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000187:drug effects*; D048051:p38 Mitogen-Activated Protein Kinases / Q000502:physiology
D000880:Anthraquinones; D004791:Enzyme Inhibitors; D007375:Interleukin-1; D061965:Matrix Metalloproteinase Inhibitors; D048049:Extracellular Signal-Regulated MAP Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D048670:MAP Kinase Kinase 4; D045726:Metalloproteases; D051722:ADAM Proteins; D000071116:ADAMTS5 Protein; C121532:ADAMTS5 protein, human; D011348:Procollagen N-Endopeptidase; D000071121:ADAMTS4 Protein; C000603918:ADAMTS4 protein, human; C020491:rhein