Cntnap4 partial deficiency exacerbates α-synuclein pathology through astrocyte-microglia C3-C3aR pathway

Area of Science:

• Neuroscience
• Neurodegenerative Diseases
• Genetics

Background:

• Parkinson's disease (PD) involves dopaminergic neuron death and alpha-synuclein aggregation.
• Cntnap4, an autism risk gene, is implicated in PD pathogenesis.
• The interaction between Cntnap4 and PD pathology requires further elucidation.

Purpose of the Study:

• To investigate the role of Cntnap4 in PD pathogenesis.
• To explore the underlying mechanisms of Cntnap4's influence on alpha-synuclein pathology and neurodegeneration.
• To identify potential therapeutic targets for PD.

Main Methods:

• Adeno-associated viral vector (AAV)-mediated overexpression of human alpha-synuclein in Cntnap4-deficient models.
• Utilized A53T alpha-synuclein transgenic mice with Cntnap4 shRNA.
• Investigated astrocyte-microglia crosstalk involving complement system components (C3, C3aR, C1q).
• Administered microglia depletion and C3aR antagonist (SB290157) in vivo.

Main Results:

• Cntnap4 deficiency exacerbated alpha-synuclein pathology, dopaminergic neuron degeneration, and motor deficits.
• Alpha-synuclein triggered astrocyte-microglia crosstalk via the C3/C3aR pathway, releasing pro-inflammatory cytokines.
• In vivo microglia depletion and C3aR antagonism rescued the aggravated pathology in Cntnap4-deficient models.

Conclusions:

• Cntnap4 plays a critical role in modulating glial crosstalk in PD.
• The Cntnap4-regulated astrocyte-microglia communication pathway is a key driver of PD progression.
• Cntnap4 and the C3aR pathway represent potential therapeutic targets for Parkinson's disease.