1,8-Cineole (Eucalyptol) in Neurodegeneration: From Pharmacological Mechanisms to Therapeutic Applications

Neurodegenerative diseases represent an enormous global burden, and due to the lack of effective therapies, the number of affected individuals continues to rise, placing a significant pressure on patients and their families. Phytochemicals such as terpenes are a group of compounds that have the potential to provide long-term neuroprotective effects by targeting multiple pathobiological pathways and supporting the brain’s natural defense mechanisms. 1,8-cineole (eucalyptol) is a monoterpene known for its anti-inflammatory and antioxidant properties, mainly utilized in the respiratory system. However, due to its ability to cross the blood–brain barrier, beneficial effects have been observed in the central nervous system. Here we examine the pharmacological mechanisms and neuroprotective potential of 1,8-cineole in the nervous tissue. Studies have shown that 1,8-cineole has the potential to suppress neuroinflammation and reduce glial activation, activate antioxidant defense mechanisms and scavenge reactive oxygen species. Additionally, 1,8-cineole has been shown to modulate central neurotransmission and synaptic plasticity, inhibit apoptotic neuronal death and regulate ion channels involved in pain modulation. This review aims to examine the therapeutic potential of 1,8-cineole in the most prevalent neurodegenerative diseases in the population, such as Alzheimer’s and Parkinson’s diseases, as well as brain injuries, including ischemic stroke and traumatic brain injury, which may lead to neurodegeneration. We also explore the potential benefits of 1,8-cineole for anxiety and depression, which occur as early symptoms or common complications of neurodegenerative diseases. Given the need for novel therapeutic approaches, combination therapies that utilize the therapeutic potential of phytochemicals, such as 1,8-cineole, may enable more effective targeting of the multiple, interconnected pathobiological processes underlying neurodegenerative diseases.