Revealing the Mechanisms of Alzheimer's, Parkinson's and Huntington's Diseases Through Invertebrate Models.

The neural circuits of the human brain are highly complex (due to the number of neurons and the diversity of synaptic connections), hindering the analysis of the pathological mechanisms of neurodegenerative diseases. Invertebrates with simple yet well-differentiated nervous systems have a natural advantage over mammalian model organisms in the identification of pathogenic genes and functional studies of neurodegenerative diseases. They can provide unique and profound insights into the pathogenesis of complex human neurodegenerative diseases and the formulation of intervention strategies. This article reviews the conserved mechanisms of three neurodegenerative diseases across species, including protein homeostasis imbalance and aggregation toxicity, mitochondrial dysfunction and metabolic abnormalities, axonal transport defects, and loss of synaptic function. Based on research on three invertebrates in the field of neurodegeneration, namely Caenorhabditis elegans (C. elegans), Drosophila melanogaster (D. melanogaster), and Bombyx mori (B. mori), we cover three major types of neurodegenerative diseases: Alzheimer's disease (AD), Parkinson's disease (PD), and Huntington's disease (HD). The aim is to find important inspirations for the future prevention and treatment of neurodegenerative diseases from the aspects of the material basis and existing treatment strategies.