Effects of cranberry components on IL-1β-stimulated production of IL-6, IL-8 and VEGF by human TMJ synovial fibroblasts

• TMJ synovial fibroblasts produce IL-6, IL-8, and VEGF in response to IL-1β.
• Cranberry components inhibit production of pro-inflammatory proteins.
• Cranberry components inhibit activation of regulatory transcription factors.
• Cranberry NDM may be useful as a therapeutic agent for TMJ arthropathies.

ObjectiveOsteoarthritis (OA) in the TMJ is characterized by deterioration of articular cartilage and secondary inflammatory changes. Interleukin-1β (IL-1β) stimulates IL-6, IL-8, and vascular endothelial growth factor (VEGF) in synovial fluid of TMJ with internal derangement and bony changes. The cranberry (Vaccinium macrocarpon) contains polyphenolic compounds that inhibit production of pro-inflammatory molecules by gingival cells in response to several stimulators. This study examined effects of cranberry components on IL-1β-stimulated IL-6, IL-8, and VEGF production by human TMJ synovial fibroblast-like cells.DesignCranberry high molecular weight non-dialyzable material (NDM) was derived from cranberry juice. Human TMJ synovial fibroblast-like cells from joints with degenerative OA and an ankylosed TMJ without degeneration were incubated with IL-1β (0.001–1 nM) ± NDM (25–250 μg/ml) (2 h preincubation). Viability was assessed via activity of a mitochondrial enzyme. IL-6, IL-8, and VEGF in culture supernatants were measured by ELISA; NF-κB and AP-1 transcription factors were measured in nuclear extracts via binding to specific oligonucleotides. Data analysis: ANOVA and Scheffe’s F procedure for post hoc comparisons.ResultsNDM did not affect cell viability but inhibited IL-1β stimulated IL-6, IL-8, and VEGF production in all cell lines (p<0.05). NDM partially reduced nuclear levels of NF-κB and AP-1 (p<0.04), depending upon cell line and time of exposure to IL-1β+NDM.ConclusionCranberry NDM inhibition of IL-1β-stimulated IL- 6, IL-8, and VEGF production by TMJ synovial fibroblast-like cells suggests that cranberry components may be useful as a host modulatory therapeutic agent to prevent or treat inflammatory arthropathies of the TMJ.