Cytotoxicity and potential anti-inflammatory activity of velutin on RAW 264.7 cell line differentiation: Implications in periodontal bone loss.

Abstract

OBJECTIVES:

Hypoxia-inducible factor-1α (HIF-1α) has been implicated in periodontal tissue inflammation and possibly in osteoclast differentiation, while polyphenols are known to be anti-inflammatory natural compounds that are capable of regulating the NF-κB protein complex pathway. The objective of this study was to investigate cytotoxicity and HIF-1α expression through the NF-κB pathway by polyphenol velutin (Euterpe oleracea Mart.), found in the pulp of acai fruit, during inflammatory RAW 264.7 differentiation.

DESIGN:

RAW 264.7 mouse monocyte macrophage cells were stimulated with RANKL (30ng/mL) and Porphyromonas gingivalis lipopolysaccharide (1μg/mL). Cells were treated with various concentrations of velutin (0.5-2μM) to check for viability, morphology, osteoclast differentiation, and HIF-1α expression (Western blot).

RESULTS:

Alamar blue cell viability assay showed no toxicity to RAW cells with the use of velutin in all concentrations tested (p>0.05). Velutin did not induce cell apoptosis based on caspase 3/7 assay (p>0.05). Fluorescence images stained by DAPI showed no alteration in the morphology of RAW cell nuclei (p>0.05) treated with velutin. TRAP assays demonstrated a dose-dependent reduction in osteoclast formation by velutin when compared with control (p<0.05). Velutin showed a reduction in HIF-1α expression related to IκB phosphorylation when compared with control (p<0.001).

CONCLUSIONS:

At the tested concentrations, velutin was not cytotoxic to RAW 264.7 and differentiated cells. Velutin reduced osteoclast differentiation and downregulated HIF-1α through the NF-κB pathway.

• Authors: Carlos Brito, Alexander Stavroullakis, Tatiane Oliveira, Anuradha Prakki
• Journal: Archives of oral biology (Arch Oral Biol) Vol. 83 Pg. 348-356 (Nov 2017) ISSN: 1879-1506 [Electronic] England
• PMID: 28898790 (Publication Type: Journal Article)
• Copyright: Copyright © 2017 Elsevier Ltd. All rights reserved.

Chemical References

• Anti-Inflammatory Agents, Non-Steroidal
• Flavones
• Hypoxia-Inducible Factor 1, alpha Subunit
• Lipopolysaccharides
• NF-kappa B
• RANK Ligand
• TNFSF11 protein, human
• 5,4'-dihydroxy-7,3'-dimethoxyflavone

Topics

• Animals
• Anti-Inflammatory Agents, Non-Steroidal (pharmacology)
• Blotting, Western
• Cell Differentiation (drug effects)
• Cell Survival (drug effects)
• Cells, Cultured
• Down-Regulation
• Flavones (pharmacology)
• Hypoxia-Inducible Factor 1, alpha Subunit (metabolism)
• Lipopolysaccharides
• Mice
• NF-kappa B (metabolism)
• Osteoclasts (drug effects)
• Porphyromonas gingivalis (metabolism)
• RANK Ligand (pharmacology)
• RAW 264.7 Cells