Essential oils by name and by nature: a review of their antioxidant and neuroprotective potential in Parkinson's disease

Oxidative stress (OS), resulting from an imbalance between reactive oxygen species (ROS) and endogenous antioxidants, plays a central role in the pathogenesis of neurodegenerative diseases, including Parkinson's disease (PD). The brain's high oxygen demand and abundance of polyunsaturated fatty acids make it particularly vulnerable to ROS-induced damage. Despite major advances in research, no disease-modifying treatments for PD are currently available. Consequently, increasing attention has been directed toward natural bioactive compounds with antioxidant and neuroprotective properties. Among these, essential oils (EOs), volatile plant-derived mixtures with documented antioxidant, anti-inflammatory, and neuroactive effects, are emerging as promising adjuvants for PD management. This review critically examines the antioxidant and neuroprotective effects of well-characterized EOs evaluated in both in vitro and in vivo models of neurodegeneration. Literature searches were conducted in PubMed and Scopus up to March 2025, identifying studies investigating EOs or their major components in PD-related experimental settings. Evidence indicates that essential oils derived from the Citrus and Rosa genus, and the Lamiaceae family, can reduce intracellular ROS accumulation, inhibit lipid peroxidation, enhance endogenous antioxidant enzyme activity, and modulate both apoptotic and inflammatory pathways. These multitarget actions are often attributed to synergistic interactions among EO constituents, such as limonene, linalool, thymol, and carvacrol. Owing to their low toxicity and ability to cross the blood-brain barrier, EOs represent promising natural candidates for the development of complementary therapeutic strategies in PD. Further mechanistic and translational studies are warranted to substantiate their clinical potential.