Development and characterization of Pterodon pubescens oil nanoemulsions as a possible delivery system for the treatment of rheumatoid arthritis

摘要

Rheumatoid arthritis is a systemic chronic inflammatory disease of autoimmune origin. It is characterized by progressive inflammation of the synovium, resulting in joint destruction. Treatment aims to prevent or reduce joint damage, but complete remission is rarely achieved. Therefore, identification of new active agents is important for the development of novel therapeutic alternatives. Although Pterodon pubescens oil is widely used owing to its anti-rheumatic, antinociceptive, and anti-inflammatory activities, there are no medicines on the market containing this plant oil thus far. This study aimed to optimize a nanoemulsion containing P. pubescens oil for intramuscular administration and to evaluate the influence of different ingredients, such as polysorbates and PEG castor oils, and their concentrations on the physicochemical properties of formulations. Negatively charged particles (similar to-30 mV) with a mean diameter of 199 nm were produced using 7.5% of PEG-40H castor oil, and they presented with marked pseudoplastic behavior facilitating their injection. The method was shown to be suitable for producing chemically stable nanoemulsions. This work also addressed the physical stability of nanoemulsions, which was measured by means of the analytical centrifuge LUMiSizer (R), and this procedure disclosed the absence of demixing phenomena on majority of samples. (C) 2015 Elsevier B.V. All rights reserved.