Quercetin and Mercury In Vitro Anti-Proliferative Effect in Human Astrocytoma Cells

Mercury (Hg) is a toxic heavy metal to which we are exposed in everyday life. Exposure to environmental Hg may lead to toxicity in the human body associated with major health issues. Quercetin (QE) on the other hand, is a natural flavonoid widely distributed in higher plants and is part of the human diet. Several studies demonstrated the therapeutic and protective effects of QE against multiple diseases and health problems. The aim of this study is to investigate the effect of QE and Hg on the proliferation of human astrocytoma 1321N1 cell line. This study is a continuation of our previous work in which we investigated cadmium (Cd) instead of Hg. The 1321N1 cells were either treated with Hg alone, or pre- or co-treated with QE. Cell viabilities were determined by MTT assay. Results indicated that simultaneous treatment of the cells with 200 µM and 16 µM Hg for 48 hrs significantly reduced cell viability to 11.7 ± 3.1 % compared to the DMSO vehicle-treated cells. Other experiments of QE pre-treatment followed by exposure to Hg alone or with QE indicated a significant ability to reduce proliferation compared to treatment with Hg alone. In conclusion, our study suggested a synergistic anti-proliferative interaction of Hg and QE in malignantly transformed cells. However, this effect is higher when combining Cd and QE as indicated in our previous work. These data may be beneficial in exploiting the biological effect of QE for treating the malignantly transformed cells.