NLRP3 Inhibition Reduces rt-PA Induced Endothelial Dysfunction under Ischemic Conditions

Area of Science:

• Neuroscience
• Immunology
• Vascular Biology

Background:

• Recombinant tissue plasminogen activator (rt-PA) is crucial for acute ischemic stroke treatment.
• However, rt-PA use is limited by bleeding complications and damage to the blood-brain barrier (BBB).
• NLRP3 inflammasome activation is implicated in stroke pathophysiology and BBB disruption.

Purpose of the Study:

• To investigate the protective potential of NLRP3 inflammasome inhibition against rt-PA-induced BBB damage in an in vitro stroke model.
• To evaluate MCC950, a specific NLRP3 inhibitor, as an adjunct therapy to rt-PA.

Main Methods:

• Utilized immortalized brain endothelial cells (bEnd5) as an in vitro BBB model.
• Treated cells with rt-PA and MCC950 (NLRP3 inhibitor) or vehicle under normoxic and oxygen-glucose deprivation (OGD) conditions.
• Assessed cell viability, BBB integrity (Cell Index), Zonula occludens 1 expression, and NLRP3 expression.

Main Results:

• rt-PA demonstrated cytotoxicity to bEnd5 cells under OGD, indicating BBB damage.
• MCC950 significantly reduced rt-PA-induced cytotoxicity and preserved BBB integrity.
• MCC950 treatment stabilized Cell Index and Zonula occludens 1 expression, while decreasing endothelial cell death and NLRP3 expression under ischemic conditions.

Conclusions:

• NLRP3 inflammasome inhibition effectively protects the blood-brain barrier from rt-PA-induced damage.
• Targeting NLRP3 may represent a promising strategy to enhance the safety and efficacy of thrombolytic therapy in stroke.
• This approach could potentially widen the therapeutic time window for rt-PA treatment in acute ischemic stroke.