Hyaluronan oligosaccharide-induced activation of transcription factors in bovine articular chondrocytes.
OBJECTIVE
To document the activity profile of transcription factors following chondrocyte stimulation with hyaluronan (HA) hexasaccharides (HA(6)) and to determine the expression of genes whose transcriptional activation is tightly associated with the transcription factors.


METHODS
Nuclear extracts from bovine articular chondrocytes treated with HA(6) were subjected to transcription factor protein-DNA array analysis. Electrophoretic mobility shift assay (EMSA) analyses were performed to confirm the results of protein-DNA array. The gene expressions of matrix metalloproteinase 3 (MMP-3), type II collagen, and cartilage oligomeric matrix protein (COMP) were examined by quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR), and protease activity was assessed by casein zymography.


RESULTS
In the protein-DNA array analysis, 12 transcription factors were up-regulated and 2 transcription factors were down-regulated in the chondrocytes treated with HA(6). The transcription factors retinoic acid receptor (RAR), retinoid X receptor (RXR), and Sp-1 exhibited >2-fold increased activity by HA(6) treatment, as confirmed by EMSA. RT-PCR analysis showed that the expression levels of MMP-3, type II collagen, and COMP messenger RNA, which are tightly associated with the activation of RAR, RXR, or Sp-1, were up-regulated by treatment with HA(6). Addition of high molecular mass HA after HA(6) treatment resulted in abrogation of the MMP-3 induction.


CONCLUSIONS
These results suggest that HA(6) increase the activity of multiple transcription factors in chondrocytes and signal the enhanced expression of key genes involved in cartilage-matrix remodeling and turnover. The data also demonstrate that high molecular mass HA has a potential to suppress the signaling activated by HA(6).
Ohno
Shigeru
S
Rush Medical College, Rush University Medical Center, Chicago, Illinois 60612, USA.
Im
Hee-Jeong
HJ
Knudson
Cheryl B
CB
Knudson
Warren
W
D000276:Adjuvants, Immunologic / Q000235:genetics / Q000494:pharmacology*; D000818:Animals; D002358:Cartilage, Articular / Q000187:drug effects*; D002417:Cattle; D019902:Chondrocytes / Q000187:drug effects*; D015870:Gene Expression / Q000187:drug effects / Q000235:genetics; D006820:Hyaluronic Acid / Q000235:genetics / Q000494:pharmacology*; D046228:Microarray Analysis; D009844:Oligosaccharides / Q000235:genetics / Q000494:pharmacology; D015398:Signal Transduction; D014157:Transcription Factors / Q000187:drug effects* / Q000235:genetics
D000276:Adjuvants, Immunologic; D009844:Oligosaccharides; D014157:Transcription Factors; D006820:Hyaluronic Acid