Particle-Induced Inflammation and Cardiovascular Diseases

Air pollution exposure associates with significant adverse health effects leading to increased cardiovascular morbidity and mortality. Cumulative epidemiological studies show that the strongest associations are between exposure to ambient particulate matter (PM) and cardiovascular diseases of ischemic nature. Experimental data supports that these associations are causal as PM exposures lead to enhanced atherosclerosis in hyperlipidemic animal models, and suggests that the smaller particles are more pathogenic, with a greater ability to induce systemic vascular effects. Particle exposures induce a variety of prooxidant and proinflammatory effects in pulmonary and systemic tissues resulting in widespread lipid peroxidation, induction of oxidative alteration of plasma lipoproteins that increase the atherogenicity of low-density lipoproteins (LDL) and decrease the protective properties of high-density lipoproteins (HDL). Particle exposures also lead to alteration of lipid and carbohydrate metabolism, induction of insulin resistance, and contribute to the development of metabolic syndrome. This chapter reviews the epidemiological, clinical and experimental animal evidence that support the association of air pollutants with systemic pro-oxidant effects resulting in enhanced atherosclerosis and cardiometabolic effects.