The Cytoprotective Benefits of a Turmeric, Quercetin, and Rosemary Blend through Activation of the Oxidative Stress Pathway

Objective: The objective of the study is to determine whether a natural product blend of turmeric, pagoda tree seed pod (quercetin), and rosemary (TQR) extracts can protect human liver cells from oxidative stress‑induced cytotoxicity. Materials and Methods: HepG2 cells were treated with a blend of botanical extracts of TQR (1:3:5, w: w:w) and expression of genes downstream of nuclear factor (erythroid‑derived 2)‑like 2 (NRF2) activation was measured. We also measured the ability of the extract blend to protect DNA and lipids from oxidative stress by measuring via the comet assay and 8‑isoprostane production, respectively. Finally, we measured the effect of the extract blend on HepG2 cell protection against oxidative stress‑induced cytotoxicity. Results: We provide evidence that the TQR blend activates the NRF2 pathway leading to DNA protection, a decrease in lipid peroxidation, and whole cell protection against oxidative stress. Conclusion: These results suggest that consuming a blend of TQR at the ratio of 1:3:5 could provide benefits against environmental stressors that increase exposure to reactive oxygen species.