Low dose thirdhand smoke exposure enhances platelet functional responses in mice

Area of Science:

• Cardiovascular Diseases
• Toxicology
• Hematology

Background:

• Cigarette smoking is a leading preventable cause of cardiovascular diseases.
• Research has historically focused on direct and secondhand smoke, overlooking thirdhand smoke (THS).
• THS, previously considered harmless, is now recognized as a significant health risk, particularly concerning thrombogenesis.

Purpose of the Study:

• To investigate the effects of low-dose THS exposure on platelet function.
• To determine if THS exposure can modulate platelets and induce a prothrombotic state.
• To identify specific toxicants within THS responsible for these effects.

Main Methods:

• Household materials were exposed to THS (20 cigarettes/day for 1 week) and placed in mice cages for 1 month.
• Mice exposed to THS underwent platelet function assays, including tail bleeding and occlusion time measurements.
• Platelet aggregation, dense granule release, integrin activation, and phosphatidylserine (PS) exposure were analyzed.

Main Results:

• THS-exposed mice demonstrated a prothrombotic phenotype, evidenced by shortened bleeding and occlusion times.
• Enhanced platelet aggregation responses were observed in THS-exposed mice.
• Platelets from exposed mice showed potentiated dense granule release, integrin activation, and PS exposure.
• The THS toxicant NNK was found to enhance platelet aggregation and thrombus formation.

Conclusions:

• Low-dose THS exposure poses a detrimental health risk by increasing thrombosis risk.
• THS exposure leads to a hyperactive platelet phenotype, contributing to a prothrombotic state.
• The tobacco-specific toxicant NNK plays a crucial role in THS-induced platelet hyperreactivity and thrombosis.