Study the effect of phytochemicals phenethyl isothiocyanate (PEITC) and Quercetin on mitochondrial biogenesis in cancer and normal cell lines
Phytochemicals are plant-derived chemicals generally are biologically active compounds and mediate positive health benefits by targeting genes or metabolic pathways of a cell. The phytochemicals examined can be classified into main categories, such as carotenoids and polyphenols, which include phenolic acids, flavonoids and stilbenes / lignans. Quercetin is isolated from the Tridax procumbens (Linn.). Its anti-cancer activity has been well documented in vitro and in vivo. It could be pro-apoptotic as well as anti-apoptotic depending upon its concentration of it and time of exposure. Isothiocyanates are cruciferous derived phytochemicals. PEITC majorly isolated from Nasturtium officinale (watercress) has shown to mediate its anti-cancer activity through ROS-mediated pathway. It is a basic leucine zipper protein involved in protection against oxidative damage triggered by stress like injury or inflammation through regulation of the expression of anti- oxidant proteins. Under oxidative stress, inactivation of Kelch-like ECH-associated protein 1 (Keap1) occurs which is a cytosolic repressor protein that binds to Nrf2. This results in Nrf2-Keap1 complex dissociation, and hence, promoting the translocation of Nrf2 to the v nucleus where it binds to ARE (anti-oxidant response element), and induce the transcription of anti-oxidative proteins. Quercetin and PEITC treatment to the cancer cells led to decreased mitochondrial biogenesis as the NRF-2 levels diminishes as the concentration of the drug increases. The anti-oxidant levels are getting down in the cancer cells leading to ROS accumulation in the cancer cells leading ultimately to the death. Quercetin and PEITC treatment to the normal HBL-100 cells induced the mitochondrial biogenesis by increasing NRF-2 levels as the concentration of the drug increases. Confocal microscopy results also proved that treatment of quercetin or PEITC or the combination of both drugs was found to be effective in cancer cells as the mitochondria size and shape got decreased interpreted through the intensity of green dye. To conclude our study, it has been shown that quercetin and PEITC lead to increased mitochondrial biogenesis in normal cells whereas decreased mitochondrial biogenesis in cancer cells.