Exposure to polystyrene microplastics with different functional groups: Implications for blood pressure and heart

Area of Science:

• Environmental Health
• Toxicology
• Cardiovascular Science

Background:

• The cardiovascular effects of microplastic (MP) exposure are poorly understood.
• MP surface modifications with aging may alter toxicity and cellular interactions.

Purpose of the Study:

• To investigate the impact of different surface functionalized polystyrene microplastics (PS-MPs) on cardiovascular health.
• To elucidate the mechanisms behind MP-induced cardiovascular toxicity.

Main Methods:

• Exposure of Sprague-Dawley rats to unmodified and functionalized PS-MPs for 42 days.
• Measurement of blood pressure, assessment of cardiac oxidative damage and cardiomyocyte hypertrophy.
• Proteomic analysis and investigation of signaling pathways (ERK, bradykinin, nitric oxide).

Main Results:

• MP exposure led to a 22-40% increase in mean blood pressure and induced cardiac oxidative damage and hypertrophy.
• Functionalized MPs, particularly amino-modified PS-MPs, exacerbated these adverse cardiovascular effects.
• Downregulation of kininogen and bradykinin, alongside ERK activation and nitric oxide pathway inhibition, was observed.

Conclusions:

• Microplastic exposure poses a significant risk to cardiovascular health, causing elevated blood pressure and myocardial damage.
• Surface functionalization of MPs influences their toxicity, with modified MPs showing enhanced adverse effects.
• The study reveals a mechanism involving the bradykinin-nitric oxide pathway in MP-induced cardiovascular toxicity.