Polyphenols are organic compounds found in many foods and plants. These compounds are antioxidants and affect multiple intracellular pathways. Sagebrush, which is rich in polyphenols, is a food source for sage grouse. However; sage grouse (Centrocercus urophasianus) will browse some sagebrush plants (Artemisia nova) and avoid others of the same species. We hypothesize that bioactive polyphenols in the sagebrush are responsible, in part, in deterring sage grouse. In this study, the bioactivity of five polyphenols present A. nova were tested for their ability to create oxidative stress and raise intracellular GSH levels in vitro. Cultured HepG2 human liver cells were treated with varying concentrations of individual polyphenols, then GSH levels were assessed. Quercetin, treatment increased intracelllular GSH levels. However, kaempferol, a polyphenol found in greater amounts in the sagebrush avoided by sage grouse, did not increase in GSH levels. Future studies include investigating treatment with multiple polyphenols as well as other pathways that may be affected by polyphenols. Bioactive polyphenols in sagebrush may be useful in developing therapeutic medicines.

The Role of Individual Polyphenols in Sage Grouse Dietary Preferences and Their Effects on Intracellular Glutathione Levels in Cultured HepG2 cells