Preparation of cubic liquid crystal nanoparticles of puerarin and its protective effect on ischemic stroke.

The low oral bioavailability of puerarin (Pur) affects its efficacy. Preparation of puerarin cubic liquid crystal nanoparticles (Pur-Cub) enhances the protective effect of Pur against ischemic stroke (IS) by increasing its bioavailability. The average particle size, PDI, and zeta potential of Pur-Cub were 274.70 ± 16.20 nm, 0.24 ± 0.05 and -25.30 ± 2.34 mV, respectively. Polarized light microscopy (PLM) and Small angle X-ray diffraction (SAXS) identified Pur-Cub as a cubic phase (Pn3m). The in vitro release of Pur-Cub was fast and then slow, in accordance with the biphasic kinetic equation. Pur-Cub increased the penetration of Pur in the intestine (mainly the duodenum) and significantly improved the bioavailability of Pur in the blood (304.16 %) and its distribution in the brain (1.69-fold) compared to Pur suspension. Pur-Cub narrowed down cerebral infarcts and significantly reduced levels of TNF-α, IL-1β, and IL-6 in a rat model of middle cerebral artery occlusion (MCAO).