Toxicological Activities of Pteridium aquilinum Rhizomes and Fiddleheads in HPV16-Transgenic Mice

Pteridium aquilinum is a globally distributed plant species, highly adaptable to various environments and historically significant as a food source for both animals and humans. This study evaluated the in vivo effects of aqueous extracts from Pteridium aquilinum rhizomes and freeze-dried fiddleheads in a transgenic mouse model of human papillomavirus type 16 (HPV16)-induced cancer. Rhizome extract was administered in drinking water at concentrations of 0.0125, 0.025, and 0.05 g/mL for 28 days across six experimental groups (n = 5): G1 (wild-type, control), G2 (wild-type, 0.05 g/mL), G3 (HPV, control), G4 (HPV, 0.0125 g/mL), G5 (HPV, 0.025 g/mL), and G6 (HPV, 0.05 g/mL). Freeze-dried fiddleheads were incorporated into the diet at concentrations of 12.5%, 25%, and 50%, also using six groups (n = 5). Humane endpoints, body weight, and food and water consumption were monitored weekly. The rhizome extract was associated with more pronounced biological effects compared to fiddleheads, particularly at the histological and molecular levels. Conversely, freeze-dried fiddleheads were better tolerated. The results indicate that rhizomes were associated with great biological impact under the present experimental conditions, particularly in HPV16 transgenic mice, highlighting a potential synergistic effect with HPV. The potential risks associated with Pteridium aquilinum consumption, as well as preparation methods, should be carefully considered, even for rhizomes which are often regarded as less harmful than other plant parts.