Recent advances in the pharmacological effects and mechanisms of borneol and borneol-containing formulations in central nervous system diseases

Borneol is an aromatic medicinal agent widely used in traditional Chinese medicine, both as a standalone component and as an ingredient in multi-herb formulations. Its pharmacological relevance to central nervous system (CNS) disorders has attracted increasing attention, particularly in Alzheimer’s disease, Parkinson’s disease, epilepsy, ischemic stroke, and glioma. Accumulating evidence indicates that borneol may influence multiple pathophysiological processes, including brain-barrier function and drug delivery, neuroinflammation and oxidative stress, neurotransmitter homeostasis and neuronal excitability, cellular injury and death, and the clearance of pathological substances and post-injury repair. Here, we integrate and compare these mechanisms across disease contexts. Notably, although several actions of borneol appear to converge across CNS disorders, others are strongly disease- and context-dependent; for example, its effects on brain-barrier permeability, oxidative stress, and cell death may differ in direction according to disease pathology and therapeutic intent. Pharmacokinetic studies support measurable brain exposure to borneol, yet direct comparative evidence of pharmacological activity, brain disposition, and human pharmacokinetics among borneol preparations of different botanical origins and stereochemical configurations remains scarce. Borneol-containing formulations also exhibit multi-level pharmacological effects; however, because most studies lack borneol-alone, borneol-depleted, or add-back controls, these effects cannot be unequivocally attributed to borneol itself. Overall, the current evidence base remains dominated by cellular and animal studies, with several proposed mechanisms inferred primarily from changes in molecular expression or computational predictions. Robust causal validation, high-quality clinical evidence, and long-term safety data are still limited. Future studies should therefore define the dose–exposure–response relationships and disease-specific therapeutic windows of different borneol preparations, establish the independent contribution of borneol within complex formulations, and determine its genuine therapeutic value and long-term safety through rigorous mechanistic and clinical investigation.