Cell Membrane- and Vesicle-Based Bionic Nanodrugs: Applications in Central Nervous System Diseases and Exploration of Nasal–Cerebral Delivery

Central nervous system (CNS) diseases exhibit high incidence rates, and the blood–brain barrier (BBB) poses a major obstacle to drug delivery. Conventional drug delivery methods not only show limited therapeutic efficacy but also cause significant side effects. Intranasal administration offers a new strategy for CNS therapy by bypassing the BBB through the unique nasal-brain pathway, while nanodrug delivery systems (NDDSs) can improve drug delivery efficiency. On this basis, biomimetic drug delivery systems (BDDSs) based on cell membrane structure have been developed. The combination of nanoparticles modified by cell membranes or cell membrane-derived vesicles with carriers such as hydrogels creates a drug delivery system that utilizes a unique transnasal-to-brain pathway, opening new avenues for treating CNS disorders. This paper systematically reviews the classification, characteristics, and preparation strategies of BDDSs, while analyzing the anatomical pathways and physiological mechanisms of nasal–cerebral delivery. Furthermore, it delves into the biogenesis mechanisms of extracellular vesicles (EVs) and bacterial extracellular vesicles (BEVs). For CNS disorders, including glioblastoma multiforme (GBM), ischemic stroke (IS), Alzheimer’s disease (AD), and Parkinson’s disease (PD), this paper presents diverse applications and challenges of BDDSs in nasal–cerebral delivery.