Objective: To test the effect of tomato juice on the growth of human normal cells (HLF line) and tumor cells (A549 cells line) and its protective effects on DNA damages for both cells.
Methods: The effect of tomato juice on the proliferation of cells was measured by MTT assay. The comet assaywas undertaken to detect the protective effect of tomato juice on DNA damages of cells induced by potassium dichromate (K2Cr2O7).
Results: No effect of tomato juice on the growth of human normal cells and tumor cells when the proportion of tomato juice in cell culture fluid under 15%; cell growth was inhabited when the proportion of tomato juice in cell culture fluid was up to or higher than 20%. No DNA damages were identified when tomato juice was set at a concentration between 50 to 500 microL/mL. Protective effects of tomato juice at 20-100 microL/mL on DNA damages were found, showing decreased. Percentage of tailed cells and length of tails for both normal and tumor cells. A negative dose-response relationship between the concentration of tomato juice and tail length was revealed (r= -0.917, P=0.00369).
Conclusion: Tomato juice can't damage the DNA of cells, but reduce the DNA damage induced by potassium dichromate (K2Cr2O7) in both human normal and tumor cells. Furthermore, to test the effect of tomato juice on the growth of cells, we must consider the volume proportion of tomato juice in cell culture fluid, just as the result shown in our study, if the proportion of tomato juice exceed 20%, the conclusion may be unbelievable.