An In Situ Gelling Buccal Spray Containing Platelet Lysate for the Treatment of Oral Mucositis

Oral mucositis is an inflammatory disease of the mucosa lining oral cavity which leads to atrophy of the epithelium and to its ulceration to form chronic lesions. Many studies, both in vitro and in vivo, have disclosed the effectiveness of growth factors derived from platelets to enhance cell proliferation, differentiation, chemotaxis, angiogenesis and extracellular matrix synthesis involved in the healing of tissues. Despite potential usefulness of growth factors, animalderived or genetically engineered ones are currently scarcely available for regenerative therapies. The aim of the present work was to study an in situ gelling formulation to be delivered by a spraying device to the oral cavity affected by mucositis. A vehicle based on Poloxamer 407 (F127) and sodium alginate (LVG) was developed. An extemporaneous loading of the vehicle with PL was achieved. The formulation was able to quickly thermogelify at 34-35°C with a viscosity at 8°C suitable for spraying; moreover it was characterized by good mucoadhesive properties. ELISA assay evidenced that at time zero the growth factor PDGF AB was compatible with the vehicle. The in vitro wound healing test showed that the formulation enhanced cell growth as PL alone even after 72 h of contact without cell apoptosis. The overall results indicate that PL loaded in the in situ gelling F127 and LVG vehicle can be profitably employed to treat buccal mucositis.