Microemulsion-based dual delivery of malkangani and phalsa: formulation, optimization and in-vivo pharmacodynamics in rats

Alzheimer’s Disease is a prevalent form of dementia typically characterized by neurodegeneration, memory loss and cognition loss. Celastrus paniculatus (malkangani) is a well-known brain tonic in Ayurveda, while Grewia asiatica (phalsa) is reported to improve memory and cognition. This study was focused on the development and evaluation of a combined microemulsion of phalsa extract and malkangani oil. The microemulsion was prepared using the water titration method and optimized using Box Behnken Design. The optimized formulation showed particle size of 14.91±0.20 nm, 0.323±0.03 polydispersity index (PDI) and % transmittance of 96.31±0.04 %. The in-vitro drug release was estimated by media change method in 0.1 N HCl and phosphate buffer (pH 6.8) and it found to follow Higuchi order kinetics with about 90 % release up to 8 hrs. Microemulsion significantly improved inflexion ratio in elevated plus maze test; indicating improvement in learning, memory and recognition in scopolamine-induced amnesia in rat as compared to single treatment of oil or extract, however statistically non-significant effect was seen in novel object recognition test. The biochemical tests and histopathological examinations of rat brains also showed the effect of microemulsion when compared to the disease control group. This combination in microemulsion can be used as a prophylactic treatment to prevent neurodegeneration.