Effects of β-cryptoxanthin on Cytokine Production by Oral Mucosal Epithelial Cells

Objectives: Beta-cryptoxanthin (β-cry) is a carotenoid, abundantly contained in Wenzhou mandarin orange. It has recently been found to have anticancer and antioxidant effects and preventive effects on diabetes and osteoporosis. We have also reported the anti-inflammatory effects of β-cry on the periodontal membrane. However, its effects on the oral mucosa remain unknown. Thus, in the present study, we examined the effects of β-cry on oral mucosal epithelial cells.
Methods: Human oral mucosal epithelial cells (HO-1-N-1) were used in the experiment. They were seeded on a plate. After reaching subconfluence, they were stimulated with Porphyromonas gingivalis-derived LPS (P.g. LPS) for 24 hours. Then, after the addition of β-cry, the cells were cultured for an additional 24 hours. Subsequently, the cells and culture supernatants were collected to examine the expressions of inflammatory cytokines in the cells by real-time RT-PCR and the productions of inflammatory cytokines in the culture supernatants by ELISA. The phosphorylation of MAPK in the cells was also examined by Western blotting.
Results: The P.g. LPS stimulation significantly increased the productions of IL-1β, IL-6, and TNF-α in HO-1-N-1, which were reduced by the addition of β-cry. The P.g. LPS stimulation also enhanced the phosphorylation of MAPK.
Conclusions: Beta-cry may have anti-inflammatory effects on the oral mucosa. Thus, β-cry derived from natural food may serve as a safe therapeutic agent for inflammatory diseases in the oral mucosa.