Allium cepa L. and Quercetin Inhibit RANKL/Porphyromonas gingivalis LPS-Induced Osteoclastogenesis by Downregulating NF-kappa B Signaling Pathway

作者：Oliveira Tatiane; Figueiredo Camila A^*; Brito Carlos; Stavroullakis Alexander; Ferreira Ana Carolina; Nogueira Filho Getulio; Prakki Anuradha

来源：Evidence-Based Complementary and Alternative Medicine, 2015, 2015: 704781.

DOI：10.1155/2015/704781

Objectives. We evaluated the in vitro modulatory effects of Allium cepa L. extract (AcE) and quercetin (Qt) on osteoclastogenesis under inflammatory conditions (LPS-induced). Methods. RAW 264.7 cells were differentiated with 30 ng/mL of RANKL, costimulated with PgLPS (1 mu g/mL), and treated with AcE (50-1000 mu g/mL) or Qt (1.25, 2.5, or 5 mu M). Cell viability was determined by alamarBlue and protein assays. Nuclei morphology was analysed by DAPI staining. TRAP assays were performed as follows: p-nitrophenyl phosphate was used to determine the acid phosphatase activity of the osteoclasts and TRAP staining was used to evaluate the number and size of TRAP-positive multinucleated osteoclast cells. Von Kossa staining was used to measure osteoclast resorptive activity. Cytokine levels were measured on osteoclast precursor cell culture supernatants. Using western blot analysis, p-I kappa B alpha and I kappa B alpha degradation, inhibitor of NF-kappaB, were evaluated. Results. Both AcE and Qt did not affect cell viability and significantly reduced osteoclastogenesis compared to control. We observed lower production of IL-6 and IL-1 alpha and an increased production of IL-3 and IL-4. AcE and Qt downregulated NF-kappa B pathway. Conclusion. AcE and Qt may be inhibitors of osteoclastogenesis under inflammatory conditions (LPS-induced) via attenuation of RANKL/PgLPS-induced NF-kappa B activation.

• 出版日期2015