Journal of Dentistry and Oral CareJournal of Dentistry and Oral CareJournal of Dentistry and Oral CareJournal of Dentistry and Oral Care2379-1705Ommega Online PublishersNew Jersey, USA15610.15436/2379-1705.15.012Research ArticleEpigallocatechin Gallate Differentially Modulates Interleukin Secretion in Nicotine and TNFα-Treated Human Gingival Epithelial CellsEpigallocatechin Gallate Differentially Modulates Interleukin Secretion in Nicotine and TNFα-Treated Human Gingival Epithelial CellsMichelle A. WheaterDepartment of Biomedical and Diagnostic Sciences University of Detroit Mercy School of Dentistry Detroit Michigan USAEditor* E-mail: wheatemi@udmercy.edu
The authors have declared that no competing interests exist.
20150806201512JDOC-15-RA-156/01224042015020620152015Creative Commons Attribution LicenseThis is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. nbsp 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 mu g 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 mu g ml EGCG and 3 Treated for 24 hours with 0 1 mM nicotine prior to challenge with 10 ng ml TNF alpha for 1 hour or 4 Not treated with nicotine but challenged with TNF alpha 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 TNF alpha for 1 hour or 6 Not treated with nicotine but challenged with TNF alpha for 1 hour prior to analysis Culture medium samples were assayed for levels of secreted interleukins IL-1 alpha IL-1 beta 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 le 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-1 alpha IL-1 beta IL-6 and IL-8 in nicotine and TNF alpha -treated cells p lt 0 01 In contrast the presence of EGCG resulted in a significant increase in the secretion of IL-10 in nicotine and TNF alpha -treated cells p lt 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 TNF alpha 10