Biochemical investigation on the bioactive properties of the Posidonia oceanica (L.) Delile marine plant

Posidonia oceanica (L.) Delile is an endemic marine plant of the Mediterranean Sea of great ecological importance. Although the literature tells of a millennial relationship between P. oceanica and humans and despite the tradition has handed down the use of this seagrass as a natural herbal remedy, the potential benefits of P. oceanica for human health are poorly documented. The research group of Prof. Degl'Innocenti of the Department of Biomedical, Experimental and Clinical Sciences "Mario Serio" (University of Florence) was among the first to explore the bioactivities of a hydroalcoholic extract from P. oceanica leaves (POE), shedding light on its efficacy and non-toxic nature in cell-based experimental models. The possibility of working with a mixture of compounds of marine origin able to act synergistically without leaving signs of cellular toxicity has aroused my interest in continuing to explore the bioactive properties of POE with particular reference to mechanisms and molecular interactions and targeted signalling pathways underlying its activity, with the future prospective of exploring its potential benefits, hitherto unexplored, for human health. During my research activity, I have achieved excellent results related to the ability of POE to inhibit the migration of cancer cells (such as human fibrosarcoma HT1080 cells and human neuroblastoma SH-SY5Y cells) without any effects on cell viability. A more in-depth investigation of the mechanism of action of POE revealed that the phytocomplex controlled cell migration process through the activation of a transient autophagic flux. During my research, nanotechnology was also investigated as an innovative system for the nano-delivery of phytocomplexes as well. In particular, Soluplus® polymeric nanomicelles proved to be an exceptional delivery system capable of increasing the aqueous solubility of POE and bio-enhancing its anti-migratory ability on SH-SY5Y cells. In light of a tradition handed down in Anatolia on the antidiabetic role of P. oceanica, confirmed by an in vivo study in animal models, my research activity investigated the properties of POE as an antioxidant, anti-inflammatory and anti-glycation agent. In fact, it is well known that oxidative stress and inflammation are among the factors characterizing the pathophysiology of diabetes, while protein glycation is a crucial event responsible for the onset of diabetics complications under chronic hyperglycemia. The results obtained with my research help to give a more complete picture of the POE molecular mechanisms of action by shedding light on its potential benefits in the management of chronic diseases such as diabetes and related complications, but also of other inflammatory-related diseases, including cancer. So, overall my mainly cell-based experimental research used a marine resource of extreme environmental importance to explore it in terms of bioactivity from a biochemical point of view, highlighting that the P. oceanica phytocomplex is undoubtedly a promising resource of effective and non-toxic bioactive compounds. My research also established POE bioactivities also in in vivo animal models, opening new research perspectives concerning the development of alternative and complementary POE-based therapeutic strategies against various diseases. This research activity carried out during the three years of the PhD is disclosed in papers published in international peer-reviewed scientific journals.