Role of plant-derived alkaloids in modulating neurodegenerative diseases: Insights into phytopharmacological mechanisms

Neurodegenerative diseases (NDs) such as Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), and amyotrophic lateral sclerosis (ALS) are among the most challenging medical conditions in aging populations. Current treatments, like cholinesterase inhibitors and dopaminergic agents, offer limited symptomatic relief but fail to halt disease progression. This review examines the role of plant-derived alkaloids, such as galantamine, huperzine A, berberine, and harmine, which have demonstrated neuroprotective effects across multiple mechanisms, including neurotransmitter modulation, anti-inflammatory effects, antioxidant properties, and mitochondrial support. Although challenges such as poor bioavailability, toxicity, and regulatory barriers exist, alkaloids present a promising alternative to conventional synthetic drugs. We also explore ethnopharmacological insights from traditional medicine systems to bridge ancient knowledge with modern pharmacological research.