Neuroprotection beyond convention: experimental and molecular insights into Rhus toxicodendron in Parkinson’s disease: A narrative review

Background: Parkinson’s Disease (PD) is the second most common age-related neurodegenerative disorder and is primarily characterised by progressive loss of dopaminergic neurons, mitochondrial dysfunction, oxidative stress, and pathological aggregation of α-synuclein encoded by the SNCA gene. Despite significant advances in pharmacological management, current therapies mainly provide symptomatic relief and do not effectively halt disease progression. Increasing interest has therefore been directed toward complementary and alternative approaches, including homoeopathy, for exploring potential neuroprotective strategies in chronic neurodegenerative disorders. Objective: To critically review the existing literature on the pathophysiology of Parkinson’s disease and to examine the potential neuroprotective role of homoeopathic Rhus toxicodendron, with particular emphasis on molecular targets such as SNCA and PARK7 (DJ-1), experimental cellular models, and translational research perspectives. Methods: A narrative review of published experimental and mechanistic studies was conducted, focusing on Parkinson’s disease pathogenesis, molecular targets involved in oxidative stress regulation, and in vitro neurodegenerative models. Special attention was given to studies utilising PC12 cell lines exposed to oxidative stress–inducing agents, along with molecular and cellular assays, including RT-PCR for gene expression analysis and MTT-based cell viability assays. Additionally, available evidence from homoeopathic dilution research and phytochemical investigations of Rhus species was examined to understand potential biological plausibility and mechanistic pathways. Conclusion: Emerging experimental evidence suggests that homoeopathic preparations and phytochemical components of Rhus species may influence cellular pathways associated with oxidative stress and neuroprotection. However, current findings remain largely preliminary and are limited by methodological variability and a scarcity of well-designed translational studies. Future research integrating robust experimental models, molecular analysis, and clinical validation is necessary to clarify the therapeutic relevance of Rhus toxicodendron in Parkinson’s disease and to bridge the gap between laboratory findings and clinical application.