Animal Cell Cultures as In Vitro Models for the Study of Phytoextracts Biological Activity

Plants, herbs and ethnobotanicals have been used since ancient times and are still used throughout the world for treatment of diseases, not only in human but also in veterinary medicine. In recent years, the increasing interest in the use of herbal medicines involves critical issues, concerning the quality and safety of natural products. Consequently, the research to obtain scientific evidence on phytochemical characterization, biological activity and effectiveness of traditional remedies is increasingly needed. The main purpose of this research project was the evaluation of the biological activity of selected anti-inflammatory and anticancer phytoextracts in in vitro cellular models, in accordance with the European Directive 2010/63/EU on the protection of animals used for scientific purposes on the base of the “3Rs” principles. Considering swine an important animal model for translational medicine, an inflammatory model developed in primary culture of porcine aortic endothelial cells (pAECs) stimulated by LPS was chosen to evaluate the biological activity of Boswellia serrata and Cucumis sativus extracts. The obtained results confirmed the anti-inflammatory activity of both extracts on endothelial cells, suggesting a potential pharmaceutical application. Naturally occurring tumours in dogs present clinical and biological similarities to human cancers and make the dog an important spontaneous animal model in comparative medicine. Canine osteosarcoma cell line (D-17) was chosen to evaluate cytotoxicity and anti-proliferative effects of a hydroalcoholic extract of Artemisia annua. The preliminary results confirmed the cytotoxicity of A. annua also in this canine tumour cell line. In conclusion, in vitro models based on animal cell cultures have shown to be a significant preclinical tool, contributing to the application of the "Replacement" principle. Finally, this study confirmed the importance of research in phytotherapy for a quality and safe use of herbal medicine, not only in human but also in veterinary medicine.