Analgesic and Anti-inflammatory Effects of Free and Nanoencapsulated Green Propolis Extract from the Northeastern Brazilian Caatinga Biome.

Abstract

The Brazilian Caatinga green propolis (GP) is known for its significant biological activities; however, its incorporation into pharmaceutical formulations is hindered by its resinous nature and low solubility. This study investigates the analgesic and anti-inflammatory effects of both free GP and nanoencapsulated GP (GPN). The optimized oil/water nanoformulation maintained stability over a period of 28 days, exhibiting minimal alterations in particle size (approximately 200 nm) and polydispersity index. GPN demonstrated notable inhibition of nociception at a concentration of 27 mg/mL in mice during the formalin test. In the thermal stimulus test, GP exhibited significant analgesic effects at 9 and 60 mg/kg in phase I, while GPN achieved this effect at 9 mg/kg. In phase II, GP at 90 mg/kg showed analgesic effects in response to thermal stimuli. GPN also reduced edema from the third hour onward at 9 mg/kg, matching the effects of higher GP concentrations (90 mg/kg). These findings underscore the enhanced efficacy of GPN. Although this preliminary formulation requires further optimization, it demonstrated promising biological activity in the evaluated assays.