Toxicological and biochemical effects of different beverages on human intestinal cells

The objective of the present study was to examine and compare the effects of frequently consumed beverages on the human intestinal cell line, Caco-2, in terms of toxicity, growth, and differentiation. For this purpose, Caco-2 cells were incubated for 24 h in the presence of: a mineral water, fresh orange juice, packaged orange juice, a cola drink, an energy drink, black, camomille, and green teas, and drip coffee. Toxicity was evaluated firstly by measuring the lactate dehydrogenase leakage from the cells and secondly by performing the MTT assay. Cell differentiation was determined by measuring two brush border membrane enzyme activities. Growth rates of Caco-2 cells were evaluated by cell counting. The results indicated that there were no significant differences between the beverages in toxicity and cell proliferation. Cells exposed to fresh orange juice exhibited higher tetrazolium reduction rates in the MTT assay (121.3% of control). These cells also showed higher succinate cytochrome c reductase activities than the other samples, implying that the contents of fresh orange juice, such as ascorbic acid, stimulated mitochondrial metabolism. The alkaline phosphatase and aminopeptidase N activities of the Caco-2 cells lay between 61.50 and 110.00%, indicating a partial influence of some beverages on Caco-2 differentiation. (C) 1999 Canadian Institute of Food Science and Technology. Published by Elsevier Science Ltd. All rights reserved.