Studies have linked exposure to ultrafine particulate matter (PM) and adverse cardiovascular events. Particulate matter-induced oxidative stress is believed to be a key mechanism underlying observed adverse vascular effects. Advanced age is one factor known to decrease anti-oxidant defenses and confer susceptibility to the detrimental vascular effects seen following PM exposure. The present study was designed to investigate the vasomotor responses following ultrafine PM exposure in wild type (WT) and superoxide dismutase 2 deficient (SOD2+/-) mice which possess decreased anti-oxidant defense. Thoracic aortic rings isolated from young and aged WT and SOD2+/- mice were exposed to ultrafine PM in a tissue bath system. Aortic rings were then constricted with increasing concentrations of phenylephrine, followed by relaxation with rising amounts of nitroglycerin (NTG). Data demonstrated that ultrafine PM decreased the relaxation response in both young WT and young SOD2+/- mouse aortas, and relaxation was significantly reduced in young SOD2+/- compared to WT mice. Ultrafine PM significantly diminished the NTG-induced relaxation response in aged compared to young mouse aortas. After ultrafine PM exposure, the relaxation response did not differ markedly between aged WT and aged SOD2+/- mice. Data demonstrate that the greater vascular effect in aortic rings in aged mice ex vivo after ultrafine PM exposure may be attributed to ultrafine PM-induced oxidative stress and loss of anti-oxidant defenses in aged vascular tissue. Consistent with this conclusion is the attenuation of NTG-induced relaxation response in young SOD2+/- mice.

This dataset is associated with the following publication: Carter, J., N. Madamanchi , G. Stouffer, M. Runge, W. Cascio, and H. Tong. Ultrafine Particulate Matter Exposure Impairs Vasorelaxant Response in Superoxide Dismutase 2 Deficient Murine Aortic Rings. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH - PART A: CURRENT ISSUES. Taylor & Francis, Inc., Philadelphia, PA, USA, 81(5): 106-115, (2018).