Abstract
Most Alzheimer's disease drugs do not work efficiently because of the blood-brain barrier. Therefore, we designed a new nanopreparation (PS-DZP-CHP): cholesterol-modified pullulan (CHP) nanoparticle with polysorbate 80(PS) surface coverage, as donepezil (DZP) carrier to realize brain tissue delivery. By size analysis and isothermal titration calorimetry, we chose the optimal dosing ratio of the drug with nanomaterials (1:5) and designed a series of experiments to verify the efficacy of the nanoparticles. The results of in vitro release experiments showed that the nanoparticles can achieve continuous drug release within 72 h. The results of fluorescence observation in mice showed a good brain targeting of PS-DZP-CHP nanoparticles. Furthermore, the nanoparticle can enhance the drug in the brain tissue concentration in mice. DZP-CHP nanoparticles were used to pretreat nerve cells with Aβ protein damage. The concentration of lactate dehydrogenase was determined by MTT, rhodamine 123 and AO-EB staining, which proved that DZP-CHP nanoparticles had a protective effect on the neurotoxicity induced by Aβ(25-35) and were superior to free donepezil. Microthermal perpetual motion meter test showed that PS-DZP-CHP nanoparticles have an affinity with apolipoprotein E, which may be vital for this nanoparticle targeting to brain tissue.