Table 1.

Key molecular mechanisms and their therapeutic targets in neurodegenerative diseases.

Mechanism	Neurodegenerative Disease	Key Molecular Targets	Therapeutic Approaches	Notable Studies (High Citations)
Protein misfolding and aggregation	Alzheimer’s, Parkinson’s	Amyloid-beta, tau, alpha-synuclein	Anti-aggregation agents, tau inhibitors, immunotherapy	Selkoe (2002) [86], Spillantini et al. (1998) [87]
Neuroinflammation	All (AD, PD, ALS, HD)	Microglia, cytokines (TNF-α, IL-1β), NLRP3 inflammasome	Anti-inflammatory agents, cytokine inhibitors	Heneka et al. (2015) [88], Amor et al. (2010) [89]
Mitochondrial dysfunction	ALS, Huntington’s	Electron transport chain complexes, mtDNA	Antioxidants, mitochondrial enhancers	Lin and Beal (2006) [90], Bhatt et al. (2021) [91]
Genetic and epigenetic regulation	Alzheimer’s, ALS, Huntington’s	APOE ε4, SOD1, HTT, DNA methylation, histone modifications	Gene silencing (RNAi, ASOs), CRISPR, epigenetic modulators	De Strooper and Karran (2016) [92], Finkbeiner et al. (2011) [93]
Synaptic dysfunction	Alzheimer’s, Parkinson’s	Cholinergic (ACh), dopaminergic systems, NMDA receptors	Synaptic modulators, neurotrophic factors	Stanciu et al. (2020) [94], Dauer and Przedborski (2003) [95]