The purpose of this study was to evaluate the effect of topical application of nanoliposomal avocado/soybean unsaponifiables (NANOCEN) on inflammation inhibition and pain relief in mice. NANOCEN was prepared by the injection method and characterized for vesicle size, charge, entrapment efficiency, in vitro release, and 1-month vesicle stability. The analysis of ASU formulation showed that liposomes had an average size of around 146 nm with a surface charge of - 43 mV. SEM and TEM imaging confirmed the spherical shape of the nanovesicles in ASU formulation. Moreover, ASU nanoliposomes had a high entrapment efficiency (96%) and exhibited significantly (p < 0.0001) sustained release of the drug in vitro model. The topical NANOCEN (ASU 2%) showed robust anti-inflammatory (p < 0.01) and analgesic effect (p < 0.01) superior to ibuprofen 5%. The histopathology of the inflamed tissues confirmed that the topical ASU formulation potentially (p < 0.001) inhibited infiltration of inflammatory cells. Our findings suggest that the topical formulation of NANOCEN may have local applications for pain relief in medicine.
Keywords: Arthrocen; Avocado soy unsaponifiables; Inflammation; Nanoliposome; Osteoarthritis; Pain; Treatment.