Epigallocatechin Gallate Differentially Modulates Interleukin Secretion in Nicotine and TNFα-Treated Human Gingival Epithelial Cells
Affiliation
Department of Biomedical and Diagnostic Sciences, University of Detroit Mercy School of Dentistry, Detroit, Michigan, USA
Corresponding Author
Michelle A. Wheater, Department of Biomedical and Diagnostic Sciences, University of Detroit Mercy School of Dentistry, Detroit, Michigan, USA. Tel: (313) 494-6634; Fax: (313) 494-6643; E-mail: wheatemi@udmercy.edu
Citation
Wheater, M., et al. Epigallocatechin Gallate Differentially Modulates Interleukin Secretion in Nicotine and TNFα-Treated Human Gingival Epithelial Cells. (2015) J Dent & Oral Care 1(2): 1- 5.
Copy rights
©2015 Wheater, M. This is an Open access article distributed under the terms of Creative Commons Attribution 4.0 International License
Keywords
Abstract
Objectives: To determine the effects of Epigallocatechin Gallate (EGCG), a major catechin component of green tea, on cytokine expression in a human oral epithelial cell culture model of nicotine use.
Methods: Confluent gingival epithelial cells in wells of a 24-well plate were subjected to one of six treatments. For controls cells received 1) No treatment or 2) Were treated with 10 μg /ml EGCG for 1 hour and cultured for 24 hours prior to analysis. A set of cells were pre-treated for 1 hour with 10 μg /ml EGCG and 3) Treated for 24 hours with 0.1 mM nicotine prior to challenge with 10 ng/ml TNFα for 1 hour, or 4) Not treated with nicotine but challenged with TNFα for 1 hour prior to analysis. A setof cells were not pre-treated with EGCG and 5) Treated for 24 hours with 0.1 mM nicotine prior to challenge with 10 ng/ml TNFα for 1 hour, or 6) Not treated with nicotine but challenged with TNFα for 1 hour prior to analysis. Culture medium samples were assayed for levels of secreted interleukins IL-1α, IL-1β, IL-4, IL-6, IL-8, and IL-10 by ELISA. Statistical analysis was completed for individual interleukins using ANOVA and Tukey post-test with probability set at p ≤ 0.05.
Results: The levels of IL-4 for all treatments were below the detection limit of the ELISA. EGCG significantly suppressed the secretion of IL-1α, IL-1β, IL-6 and IL-8 in nicotine and TNFα-treated cells (p < 0.01). In contrast, the presence of EGCG resulted in a significant increase in the secretion of IL-10 in nicotine and TNFα-treated cells (p < 0.001).
Conclusion: This study suggests that tea catechins such as EGCG may function to suppress pro-inflammatory cytokines and to increase the secretion of the anti-inflammatory cytokine IL-10 in cells challenged by nicotine and TNFα.
