Expression of hypoxia inducible factor-2 alpha in overloaded- stress induced destruction of mandibular condylar chondrocytes

Arch Oral Biol. 2017 May:77:51-54. doi: 10.1016/j.archoralbio.2017.01.008. Epub 2017 Jan 18.

Abstract

Objective: To study the protein expression of HIF-2α in condylar chondrocytes under the different stress loading, to investigate the possible effects of HIF-2α involved in the mortality of condylar chondrocytes under overloaded- stress.

Materials and methods: Chondrocytes were isolated from TMJ condylar cartilage and cultured in hypoxia-incubator. Chondrocytes were divided into 4 groups: 0, 1000, 2000, 3000 ustrain group, which was subjected to cyclic tensile strain (CTS) of 0.5Hz for 2h. The rate of cell mortality was calculated. Western blot was used to measure the expression of HIF-2α and it's downstream catabolic factors (MMP3, MMP13, ADAMTS4) in protein levels respectively.

Results: With the increase of CTS, both of the rate of cell mortality and protein expression of HIF-2α increased significantly (p<0.05). The same tendency was also found in it's downstream catabolic factors (MMP3, MMP13, ADAMTS4) in protein levels (p<0.05).

Conclusions: The results indicated that elevated expression of HIF-2α may be a possible mechanism related to overloaded- stress induced mortality of condylar chondrocytes.

Keywords: ADAMTS4; Condylar cartilage; HIF-2α; MMP13; MMP3.

MeSH terms

  • ADAMTS4 Protein / metabolism
  • Apoptosis
  • Basic Helix-Loop-Helix Transcription Factors / metabolism*
  • Blotting, Western
  • Cells, Cultured
  • Chondrocytes / metabolism*
  • Humans
  • Mandibular Condyle / cytology
  • Mandibular Condyle / metabolism*
  • Matrix Metalloproteinase 13 / metabolism
  • Matrix Metalloproteinase 3 / metabolism
  • Stress, Mechanical

Substances

  • Basic Helix-Loop-Helix Transcription Factors
  • endothelial PAS domain-containing protein 1
  • Matrix Metalloproteinase 13
  • Matrix Metalloproteinase 3
  • ADAMTS4 Protein
  • ADAMTS4 protein, human