Formulation and characterization of chitosan nanoparticles loaded with neuroprotective flavonoid from Phyllanthus niruri Linn

Niruriflavone (NF) a natural flavonoid isolated from Phyllanthus niruri Linn through bio-guided isolation, demonstrated significant neuroprotective efficacy by inhibiting oxidative stress, acetylcholinesterase, and 5-lipoxygenase which were beneficial for the treatment of Alzheimer’s disease (AD). It was further confirmed by in-vivo studies. Natural product usage in AD therapy has a lot of limitations. Nanotechnology addresses the challenges in natural product drug delivery for AD. Hence, the goal of this study was to develop an oral delivery system for the controlled release of niruriflavone. Also, the neuroprotective and antioxidant properties of niruriflavone-loaded chitosan nanoparticles (NFLC) were evaluated in aluminium chloride-induced AD rats. NFLC was prepared by the ionic gelation method and characterized by particle size, zeta potential, morphology, encapsulation efficacy, in vitro drug release kinetics, and stability. The particle size of synthesized NFLC was 192.3 nm with a zeta potential of + 20.7 mV and a polydispersity index of 0.509. The microcrystalline aggregate of nanoparticles and the rough surface was revealed by transmission and scanning electron microscopies. The cytotoxicity study of NFLC is conducted in neuroblastoma cell line SH-SY5Y which was evaluated by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. NFLC was discovered to be biocompatible and cell viability by about 85%. It showed improved antioxidative enzyme levels and decreased oxidative products. The ability of NFLC to target the blood–brain barrier and treat AD will be validated with in-vivo studies. Graphical abstract