Inhibiting EGFR/HER-2 ameliorates neuroinflammatory responses and the early stage of tau pathology through DYRK1A

Area of Science:

• Neuroscience
• Immunology
• Pharmacology

Background:

• Epidermal Growth Factor Receptor (EGFR) and Human Epidermal growth factor Receptor 2 (HER2) signaling pathways are implicated in cancer and potentially neuroinflammation.
• The neuroinflammatory effects of EGFR/HER2 inhibitors like varlitinib are not well understood.
• Neuroinflammation and tau pathology are key features of neurodegenerative diseases.

Purpose of the Study:

• To investigate the impact of varlitinib on lipopolysaccharide (LPS)- and tau-mediated neuroinflammatory responses.
• To elucidate the underlying molecular mechanisms of varlitinib's effects on glial cells and tau pathology.
• To evaluate the therapeutic potential of varlitinib in preclinical models of neuroinflammation and tauopathy.

Main Methods:

• In vitro studies using BV2 microglial cells and primary astrocytes treated with LPS.
• In vivo studies using LPS-treated wild-type mice and tau-overexpressing PS19 mice at different ages.
• Analysis of inflammatory markers (IL-1β, iNOS, NLRP3 inflammasome), signaling pathways (AKT, FAK, NF-κB), and tau hyperphosphorylation.

Main Results:

• Varlitinib reduced LPS-induced inflammatory gene expression and signaling in microglial and astroglial cells.
• Varlitinib inhibited NLRP3 inflammasome activation in glial cells and in LPS-treated mice.
• In PS19 mice, varlitinib decreased glial activation and tau hyperphosphorylation, particularly in younger mice, by downregulating DYRK1A.

Conclusions:

• Varlitinib demonstrates significant anti-neuroinflammatory effects against LPS and early tau pathology in preclinical models.
• The drug modulates key inflammatory pathways, including the NLRP3 inflammasome and AKT signaling.
• Varlitinib shows therapeutic promise for neuroinflammatory conditions and early-stage tauopathies.