# Targeting Microglial CD49a Inhibits Neuroinflammation and Demonstrates Therapeutic Potential for Parkinson's Disease

## TL;DR

This study shows that targeting CD49a in microglia reduces neuroinflammation and protects neurons in a Parkinson's disease model.

## Contribution

The study identifies CD49a as a novel therapeutic target in Parkinson's disease and demonstrates its role in neuroinflammation and neurodegeneration.

## Key findings

- Microglial CD49a is upregulated in chronically activated states and contributes to neuroinflammation in Parkinson's disease.
- Knockdown of CD49a in microglia reduces hyperactivation, mitochondrial dysfunction, and NLRP3 inflammasome assembly.
- The disintegrin obtustatin inhibits CD49a and ameliorates motor deficits in Parkinson's disease models.

## Abstract

Persistent microglial activation drives chronic neuroinflammation, a characteristic pathological hallmark of neurodegenerative disorders, including Parkinson's disease (PD). Although integrin receptor CD49a (Itga1 gene) serves as a canonical biomarker of tissue‐resident immune populations, its microglial expression patterns, functions, and signaling pathways have not been elucidated. In this study, we aim to investigate the impact of CD49a in hyperactivated microglia on PD pathogenesis and elucidate downstream signaling pathways. Specifically, we demonstrate microglia‐enriched CD49a expression with pathologically significant upregulation particularly in microglia adopting chronically activated states. Specific Itga1 knockdown attenuates microglial hyperreactivity and markedly improves motor deficits in PD mouse models. Mechanistically, transcriptomic profiling of isolated microglia from mouse substantia nigra reveals significant enrichment in neurodegeneration and inflammation pathways, with PGAM5 emerging as a central regulatory node. Conditional microglial Itga1 knockdown ameliorates mitochondrial dysfunction and suppresses NLRP3 inflammasome assembly via PGAM5 downregulation, thereby preserving dopaminergic neurons from neuroinflammatory degeneration. Furthermore, the disintegrin polypeptide obtustatin specifically antagonizes microglial CD49a, suppressing microglial hyperactivation and consequent chronic neuroinflammation, and ultimately ameliorating motor deficits in PD models. Collectively, these findings establish microglial CD49a‐targeted therapy as a novel therapeutic paradigm for PD, positioning obtustatin as a promising clinical candidate with demonstrable translational potential across neuroinflammatory and neurodegenerative disorders.

This study shows that integrin receptor CD49a (Itga1 gene) is significantly upregulated in hyperactivated microglia and microglia‐specific knockdown of Itga1 rescues neuroinflammation and neurodegeneration in a chronic Parkinson's disease (PD) model by targeting PGAM5‐mediated mitochondrial dysfunction and NLRP3 activation. Targeted inhibition of CD49a with the disintegrin peptide ameliorates motor deficits, underscoring its therapeutic potential.