Cytotoxicity Studies and Mechanism of Cell Death Mediated by Phenolic Antioxidants on Cells of Melanocytic Origin

Conference Paper
Alanazi, S. Kerr and M. . 2015
نوع عمل المنشور: 
اسم المؤتمر: 
54th Annual Meeting and ToxExpoTM
عنوان المؤتمر: 
San Diego, California
تاريخ المؤتمر: 
الجمعة, آيار (مايو) 22, 2015
مستخلص المنشور: 

Phenolic compounds have been implicated as major offending agents in melanocyte destruction and occupational vitiligo. Exposure to individuals of phenolic compounds like butylated hydroxyanisole (BHA), 4-tertiary butylphenol (4TBP) and hydroquinone (HQ) is commonplace since these agents are used as additives in the food, pharmaceuticals and cosmetic industry. The purpose of this study was to investigate the cytotoxicity and mechanism of cell death of the pheolic antioxidants, BHA, 4TBP and HQ on two model melanoma cell lines SK-MEL-23 and SK-MEL-19. Approximately 1x10e4 cells from each melanoma cell line were seeded in 96-well plates and treated with different concentrations of BHA (50, 100, 250, 500μM); 4TBP (50, 100, 250, 500 μM); HQ (10, 20, 50, 100, 250 μM) or with control for 72 hours. Cells were then assayed for viability and compared to the control using the CellTiter 96 Aqueous One cell proliferation assay kit (Promega). Further quantitation of the proteolytic activities of Caspase 8, 9 and 3, as critical indicators of programmed cell death (apoptosis) was performed by fluorescence based assay kits (Biovision) to provide a mechanism of cell death for these phenolic anti-oxidants. Results indicated that BHA, 4TBP and HQ reduced the cell viability in both melanoma cell lines. Moreover, both BHA and 4TBP induced Caspase 3 and Caspase 9 levels at concentration of 500 μM. In conclusion, BHA, 4TBP and HQ were toxic to both melanoma cell lines at the higher concentrations. Cytoxicity concentrations ranged from 250 and 500 μM for BHA, 500 μM for 4TBP and 250 μM for HQ. In addition, BHA and 4TBP induced apoptotic cell death in both melanoma cell lines through their abilities to activate the Initiator Caspase 9 and the Effector Caspase 3 while there was no evidence that HQ initiated caspase dependent apoptotic cell death.