Resistin stimulates expression of chemokine genes in chondrocytes via combinatorial regulation of C/EBPβ and NF-κB

Int J Mol Sci. 2014 Sep 26;15(10):17242-55. doi: 10.3390/ijms151017242.

Abstract

To further investigate the regulation role of two chemokine genes CCL3 and CCL4 in chondrocytes in response to resistin, human primary chondrocytes and T/C-28a2 cells were cultured. The function of resistin on the chemokine genes, and the expression of C/EBPβ, NF-κB isoforms were tested using qPCR. The methods used to investigate timed co-regulation of C/EBPβ and NF-κB were NF-κB inhibitor (IKK-NBD) and C/EBPβ inhibitor (SB303580) treatments, and subcellular localization, with or without resistin stimulation. Results showed that resistin could increase the up-regulation of chemokine genes independently. Resistin increased the expression of C/EBPβ and NF-κB isoforms. C/EBPβ regulated basal activity and steadily increased over time up to 24h with resistin. NF-κB was up-regulated upon induction with resistin, peaking at 4 h. C/EBPβ and NF-κB co-enhanced the chemokines expression; inhibition of their activity was additive. The timing of activation in chondrocytes was confirmed by subcellular localization of C/EBPβ and c-rel. Chondrocytes react to resistin in a non-restricted cell-specific manner, utilizing C/EBPβ and NF-κB in a combinatorial regulation of chemokine gene expression. The activity of C/EBPβ is augmented by a transient increase in activity of NF-κB, and both transcription factors act independently on the chemokine genes, CCL3 and CCL4. Thus, resistin stimulates CCL3 and CCL4 through combinatorial regulation of C/EBPβ and NF-κB in chondrocytes.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • CCAAT-Enhancer-Binding Protein-beta / antagonists & inhibitors
  • CCAAT-Enhancer-Binding Protein-beta / genetics
  • CCAAT-Enhancer-Binding Protein-beta / metabolism*
  • Cartilage, Articular / cytology
  • Cells, Cultured
  • Chemokine CCL3 / genetics
  • Chemokine CCL3 / metabolism
  • Chemokine CCL4 / genetics
  • Chemokine CCL4 / metabolism
  • Chemokines / genetics*
  • Chemokines / metabolism
  • Chondrocytes / cytology
  • Chondrocytes / drug effects
  • Chondrocytes / metabolism
  • Humans
  • Immunohistochemistry
  • NF-kappa B / antagonists & inhibitors
  • NF-kappa B / genetics
  • NF-kappa B / metabolism*
  • Protein Isoforms / genetics
  • Protein Isoforms / metabolism
  • RNA, Messenger / metabolism
  • Resistin / pharmacology*
  • Up-Regulation / drug effects*

Substances

  • CCAAT-Enhancer-Binding Protein-beta
  • Chemokine CCL3
  • Chemokine CCL4
  • Chemokines
  • NF-kappa B
  • Protein Isoforms
  • RNA, Messenger
  • Resistin