Elvira de Mejia, a University of Illinois professor of food chemistry and food toxicology, said that apigenin alone induced cell death in two aggressive human pancreatic cancer cell lines.
Mejia asserted that they received the best results when they pre-treated cancer cells with apigenin for 24 hours, then applied the chemotherapeutic drug gemcitabine for 36 hours.
Jodee Johnson, a doctoral student in de Mejia's lab who has since graduated, said that the trick seemed to be using the flavonoids as a pre-treatment instead of applying them and the chemotherapeutic drug simultaneously.
She asserted that even though the topic is still controversial, our study indicated that taking antioxidant supplements on the same day as chemotherapeutic drugs may negate the effect of those drugs.
Johnson explained that happens as flavonoids can act as antioxidants; one of the ways that chemotherapeutic drugs kill cells is based on their pro-oxidant activity, meaning that flavonoids and chemotherapeutic drugs may compete with each other when they're introduced at the same time.
The scientists found that apigenin inhibited an enzyme called glycogen synthase kinase-3 beta (GSK-3 beta), which led to a decrease in the production of anti-apoptotic genes in the pancreatic cancer cells.
Apoptosis means that the cancer cell self-destructs because its DNA has been damaged.
In one of the cancer cell lines, the percentage of cells undergoing apoptosis went from 8.4 percent in cells that had not been treated with the flavonoid to 43.8 percent in cells that had been treated with a 50-micromolar dose. In this case, no chemotherapy drug had been added.
Treatment with the flavonoid also modified gene expression. "Certain genes associated with pro-inflammatory cytokines were highly upregulated," de Mejia said.
The study has been published in Molecular Nutrition and Food Research.
--ANI (Posted on 17-08-2013)