Astrocyte gap junction dysfunction activates JAK2-STAT3 pathway to mediate inflammation in depression.

Area of Science:

• Neuroscience
• Cell Biology
• Psychiatry

Background:

• Astrocytes play a crucial role in brain function through intercellular communication via Connexin 43 (Cx43) gap junctions.
• Dysfunctional astrocyte gap junctions are linked to depression pathogenesis and neuroinflammation.
• Transporter protein (TSPO) is a key neuroinflammatory marker upregulated in depression.

Purpose of the Study:

• To investigate the role of astrocyte gap junction dysfunction in mediating neuroinflammation in depression.
• To explore the JAK2-STAT3 signaling pathway's involvement in Cx43-mediated inflammation.
• To identify potential therapeutic targets for depression.

Main Methods:

• Utilized a chronic unpredictable stress (CUS) mouse model to induce depressive-like behaviors and assess astrocyte gap junctions in the prefrontal cortex.
• Employed Cx43 transgenic mice to conditionally knock down Cx43 in astrocytes.
• Administered protosappanin A (PTA), a JAK2-STAT3 inhibitor, to evaluate its effects on CORT-induced changes.

Main Results:

• CUS mice exhibited impaired astrocyte gap junctions, activated JAK2-STAT3 signaling, and elevated TSPO levels.
• Conditional Cx43 knockdown in astrocytes led to similar inflammatory activation and depressive-like behaviors.
• PTA treatment ameliorated CORT-induced gap junction dysfunction and TSPO upregulation.

Conclusions:

• Astrocyte Cx43 dysfunction contributes to neuroinflammation and depressive symptoms via the JAK2-STAT3 pathway.
• Targeting astrocyte Cx43 presents a novel therapeutic approach for depression.
• This study offers new insights into depression's pathogenesis and antidepressant development.