Paroxetine suppresses recombinant human P2X7 responses

Area of Science:

• Neuroscience
• Immunology
• Pharmacology

Background:

• The P2X7 receptor (P2X7) is implicated in linking inflammation with depressive disorders.
• Genetic variants of P2X7 are associated with major depression and bipolar disorders.
• P2X7 regulates the pro-inflammatory cytokine interleukin 1β (IL-1β) secretion.

Purpose of the Study:

• To investigate whether common psychoactive drugs modulate human P2X7 receptor activity.
• To explore the potential of antidepressants in reducing inflammatory responses via P2X7.

Main Methods:

• Assessed effects of common antidepressants on recombinant and native human P2X7 responses in vitro.
• Utilized HEK-293 cells expressing recombinant human P2X7 and human CD14(+) monocytes.
• Measured ATP-induced dye uptake, inward currents, and IL-1β secretion.

Main Results:

• Paroxetine inhibited human P2X7 activity (IC(50) = 24 μM) and ATP-induced currents.
• Fluoxetine and clomipramine mildly potentiated P2X7 responses.
• Trifluoperazine hydrochloride suppressed human P2X7 responses (IC(50) = 6.4 μM).
• Paroxetine and trifluoperazine did not inhibit rodent P2X7 or bind at the F95L site.
• Both drugs suppressed P2X7-induced IL-1β secretion from human monocytes.

Conclusions:

• Common antidepressants exhibit differential effects on human P2X7 receptor activity.
• Paroxetine and trifluoperazine inhibit human P2X7, reducing inflammatory cytokine secretion.
• These findings suggest P2X7 modulation as a potential therapeutic target for depression and inflammatory conditions.