Targeting signaling pathways in neurodegenerative diseases: Quercetin's cellular and molecular mechanisms for neuroprotection

Neurodegenerative diseases (NDs), including Alzheimer's disease, Parkinson's disease, and Huntington's disease, are complex and challenging due to their intricate pathophysiology and limited treatment options. This review systematically sourced articles related to neurodegenerative diseases, neurodegeneration, quercetin, and clinical studies from primary medical databases, including Scopus, PubMed, and Web of Science. Recent studies have included quercetin to impact the cellular and molecular pathways involved in neurodegeneration. Quercetin, a flavonoid abundant in vegetables and fruits, is gaining attention for its antioxidant, anti-inflammatory, and antiapoptotic properties. It regulates signaling pathways such as nuclear factor-κB (NF-κB), sirtuins, and phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt). These pathways are essential for cellular survival, inflammation regulation, and apoptosis. Preclinical and clinical studies have shown that quercetin improves symptoms and pathology in neurodegenerative models, indicating promising outcomes. The study explores the potential of incorporating laboratory research into practical medical treatment, focusing on quercetin's neuroprotective effects on NDs and its optimal dosage.