Carbon monoxide exposure in the urban environment: an insidious foe for the heart?

Area of Science:

• Cardiovascular Physiology
• Toxicology
• Environmental Health

Background:

• Carbon monoxide (CO) is known for its toxicity via hemoglobin binding.
• CO also exhibits complex biological properties, with both beneficial and harmful cardiovascular effects.
• Low-level environmental CO exposure is common but understudied.

Purpose of the Study:

• To review the dual nature of carbon monoxide in cardiovascular function.
• To summarize the pathophysiological effects of low-level CO exposure in vivo and in vitro.
• To assess CO as a potential cardiovascular risk factor.

Main Methods:

• Review of clinical observations and experimental studies on CO exposure.
• Analysis of in vivo and in vitro data concerning CO's effects on cardiac disorders and cardiomyocyte remodeling.
• Focus on low environmental CO exposure scenarios.

Main Results:

• Acute low-level CO exposure demonstrates cardioprotective properties.
• Prolonged exposure to low-level CO is deleterious, impacting redox status, ion homeostasis, intracellular calcium handling, and sympathovagal balance.
• Cardiomyocyte remodeling and cardiac disorders are observed with chronic CO exposure.

Conclusions:

• Carbon monoxide possesses significant therapeutic potential at low concentrations.
• Regular exposure to environmental CO, even at low levels, can negatively impact cardiovascular health.
• Prolonged CO exposure should be considered a cardiovascular risk factor.