Dietary Supplementation with the Red Seaweed <i>Porphyra umbilicalis</i> Protects against DNA Damage and Pre-Malignant Dysplastic Skin Lesions in HPV-Transgenic Mice

• Main Authors: Susana Santos, Tiago Ferreira, José Almeida, Maria J. Pires, Aura Colaço, Sílvia Lemos, Rui M. Gil da Costa, Rui Medeiros, Margarida M. S. M. Bastos, Maria J. Neuparth, Helena Abreu, Rui Pereira, Mário Pacheco, Isabel Gaivão, Eduardo Rosa, Paula A. Oliveira
• Format: Article
• Language: English
• Published: MDPI AG 2019-10-01
• Series: Marine Drugs
• Subjects: k14hpv16; genotoxicity assay; papillomavirus; cancer
• Online Access: https://www.mdpi.com/1660-3397/17/11/615

Some diet profiles are associated with the risk of developing cancer; however, some nutrients show protective effects. <i>Porphyra umbilicalis</i> is widely consumed, having a balanced nutritional profile; however, its potential for cancer chemoprevention still needs comprehensive studies. In this study, we incorporated <i>P. umbilicalis</i> into the diet of mice transgenic for the human papillomavirus type 16 (HPV16), which spontaneously develop pre-malignant and malignant lesions, and determined whether this seaweed was able to block lesion development. Forty-four 20-week-old HPV^+/&#8722; and HPV^{&#8722;/&#8722;} mice were fed either a base diet or a diet supplemented with 10% seaweed. At the end of the study, skin samples were examined to classify HPV16-induced lesions. The liver was also screened for potential toxic effects of the seaweed. Blood was used to study toxicological parameters and to perform comet and micronucleus genotoxicity tests. <i>P. umbilicalis</i> significantly reduced the incidence of pre-malignant dysplastic lesions, completely abrogating them in the chest skin. These results suggest that <i>P. umbilicalis</i> dietary supplementation has the potential to block the development of pre-malignant skin lesions and indicate its antigenotoxic activity against HPV-induced DNA damage. Further studies are needed to establish the seaweed as a functional food and clarify the mechanisms whereby this seaweed blocks multistep carcinogenesis induced by HPV.