Cardiovascular Effects of Ultrafine Particles in Genetically Susceptible Subjects

超细颗粒对遗传易感受试者的心血管影响

• 批准号: 7819095
• 负责人: Mark Walter Frampton
• 金额: $ 50万
• 依托单位: UNIVERSITY OF ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-30 至 2011-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7819095
• 关键词: Address; Aerosols; Affect; Air Pollution; Antioxidants; Area; Biological Availability; Blood; Blood Platelets; Blood Pressure; Blood Vessels; Blood Volume; Breathing; Caliber; Cardiac; Cardiac Output; Cardiovascular Diseases; Cardiovascular system; Cells; Cessation of life; Chemicals; Chemistry; Clinical; Clinical Research; Coagulants; Deposition; Diffusion; Distal; Double-Blind Method; Endothelium; Environment; Epithelium; Exposure to; Forearm; Free Radicals; Functional disorder; GSTM1 gene; Gene Mutation; Generations; Genes; Genetic; Genetic Determinism; Genetic Predisposition to Disease; Genotype; Glutathione S-Transferase; Health; Heart Rate; Hour; Human; Impairment; Impedance Cardiography; Injury; Leukocyte Adhesion Molecules; Leukocyte-Adhesion Receptors; Leukocytes; Lipid Peroxidation; Lung; Measurement; Measures; Morbidity - disease rate; Nitric Oxide; Nitrites; Nitrogen; Organelles; Oxidants; Oxidative Stress; Oxygen; Particulate; Particulate Matter; Pathway interactions; Patients; Peripheral; Physiological; Plasma; Platelet Activation; Plethysmography; Predisposition; Pulmonary alveolar structure; Randomized; Reactive Oxygen Species; Risk; Stroke Volume; Surface; Testing; Thrombosis; Ultrafine; Urine; Vascular Diseases; Venous; air cleaner; air filter; airway inflammation; base; capillary; experience; exposed human population; healthy volunteer; heart function; hemodynamics; mortality; novel marker; nuclear factor-erythroid 2; particle; particle exposure; peripheral blood; public health relevance; pulmonary function; reactive hyperemia; response; ultrafine particle; vasoconstriction

DESCRIPTION (provided by applicant): This application addresses broad Challenge Area (04) Clinical Research, and specific Challenge Topic, 04-ES-102: Investigating gene x environment interaction using controlled human exposures. Increases in ambient particulate matter (PM) are associated with morbidity and mortality from pulmonary and cardiovascular disease. The mechanisms and genetic determinants of susceptibility represent gaps in our understanding of the health effects of PM air pollution. Ultrafine particles (UFP, <100 nm diameter) may be particularly important with regard to cardiovascular effects because of their high specific surface area and reactive surface chemistry, with potential to deliver reactive oxygen species (ROS) to the lung and vascular space. This project will combine physiologic measures of vascular and cardiac function with novel markers of nitric oxide (NO) bioavailability and transport to test the following hypotheses: 1. Ambient UFP exposure impairs pulmonary & systemic vascular function, in part by altering NO transport and bioavailability. 2. Dysfunction in selected oxidant defense genes increases susceptibility to the pulmonary and cardiovascular effects of UFP. 3. In susceptible subjects, UFP pulmonary and cardiovascular effects will be related to markers of systemic oxidative stress, and to UFP oxidative potential. Aim: Conduct a human clinical exposure study examining pulmonary and cardiovascular responses to ambient UFP in healthy subjects with and without reduction in function of 2 antioxidant genes. Our approach will be to conduct a randomized, double-blind, 2-period crossover clinical study of exposure to concentrated ambient UFP and clean, filtered air. We will study 3 groups of 12 subjects each, with differing genotypes as follows: 1) GSTM1 null, 2) Nrf2 -617A/C, and 3) "wild type" for both genes (GSTM1+ and Nrf2 -617C/C). Effects of exposure on pulmonary vascular function will be assessed by measuring changes in pulmonary capillary blood volume and shifts in peripheral blood leukocyte adhesion molecule expression. Systemic vascular function will be assessed using blood pressure and heart rate, forearm plethysmography and reactive hyperemia, platelet activation, and circulating microparticles. Our hypothesis that NO bioavailability and transport are involved in the effects on vascular function will be tested by measuring arterial/venous gradients of nitrite, FeNOHb, and SNOHb. Cardiac function will be assessed noninvasively using impedance cardiography (ICG). Airway inflammation will be assessed by measuring pulmonary NO exchange. We will measure markers of oxidative stress/lipid peroxidation in plasma and urine. Our hypotheses will be supported if we see evidence for impaired pulmonary or systemic vascular function or altered cardiac function in one or both of the subject groups with the candidate SNPs, with a positive relationship between these effects and markers of oxidative stress. Finally, we expect to see a relationship between the oxidative potential of the UFP aerosol and physiologic effects, suggesting that at least a portion of the oxidative stress is exogenous. These studies will identify pathways, mechanisms, and genetic determinants of susceptibility for the cardiovascular effects of UFP exposure. PUBLIC HEALTH RELEVANCE: Increases in particulate air pollution are associated with increases in deaths from cardiovascular disease, but we know relatively little about how this happens, and who is most susceptible. Our proposed studies will determine the effects of very small (ultrafine) outdoor air pollution particles on blood vessel and heart function in people who may have increased susceptibility based on their genetic makeup. Healthy volunteers with and without specific gene mutations will inhale concentrated outdoor ultrafine particles on one occasion, and clean air on another occasion. Detailed measurements of lung, blood vessel, and heart function, and markers of effects in the blood, will be made before and at intervals up to 48 hours after the 2- hour exposure. We expect to see the strongest effects in the subjects with gene mutations that increase susceptibility. These studies will help determine how exposure to air pollution particles contributes to heart and vascular disease, determine whether genetic makeup affects susceptibility, and help to develop strategies to protect the most susceptible people.

DESCRIPTION (provided by applicant): This application addresses broad Challenge Area (04) Clinical Research, and specific Challenge Topic, 04-ES-102: Investigating gene x environment interaction using controlled human exposures. Increases in ambient particulate matter (PM) are associated with morbidity and mortality from pulmonary and cardiovascular disease. The mechanisms and genetic determinants of susceptibility represent gaps in our understanding of the health effects of PM air pollution. Ultrafine particles (UFP, <100 nm diameter) may be particularly important with regard to cardiovascular effects because of their high specific surface area and reactive surface chemistry, with potential to deliver reactive oxygen species (ROS) to the lung and vascular space. This project will combine physiologic measures of vascular and cardiac function with novel markers of nitric oxide (NO) bioavailability and transport to test the following hypotheses: 1. Ambient UFP exposure impairs pulmonary & systemic vascular function, in part by altering NO transport and bioavailability. 2. Dysfunction in selected oxidant defense genes increases susceptibility to the pulmonary and cardiovascular effects of UFP. 3. In susceptible subjects, UFP pulmonary and cardiovascular effects will be related to markers of systemic oxidative stress, and to UFP oxidative potential. Aim: Conduct a human clinical exposure study examining pulmonary and cardiovascular responses to ambient UFP in healthy subjects with and without reduction in function of 2 antioxidant genes. Our approach will be to conduct a randomized, double-blind, 2-period crossover clinical study of exposure to concentrated ambient UFP and clean, filtered air. We will study 3 groups of 12 subjects each, with differing genotypes as follows: 1) GSTM1 null, 2) Nrf2 -617A/C, and 3) "wild type" for both genes (GSTM1+ and Nrf2 -617C/C). Effects of exposure on pulmonary vascular function will be assessed by measuring changes in pulmonary capillary blood volume and shifts in peripheral blood leukocyte adhesion molecule expression. Systemic vascular function will be assessed using blood pressure and heart rate, forearm plethysmography and reactive hyperemia, platelet activation, and circulating microparticles. Our hypothesis that NO bioavailability and transport are involved in the effects on vascular function will be tested by measuring arterial/venous gradients of nitrite, FeNOHb, and SNOHb. Cardiac function will be assessed noninvasively using impedance cardiography (ICG). Airway inflammation will be assessed by measuring pulmonary NO exchange. We will measure markers of oxidative stress/lipid peroxidation in plasma and urine. Our hypotheses will be supported if we see evidence for impaired pulmonary or systemic vascular function or altered cardiac function in one or both of the subject groups with the candidate SNPs, with a positive relationship between these effects and markers of oxidative stress. Finally, we expect to see a relationship between the oxidative potential of the UFP aerosol and physiologic effects, suggesting that at least a portion of the oxidative stress is exogenous. These studies will identify pathways, mechanisms, and genetic determinants of susceptibility for the cardiovascular effects of UFP exposure. PUBLIC HEALTH RELEVANCE: Increases in particulate air pollution are associated with increases in deaths from cardiovascular disease, but we know relatively little about how this happens, and who is most susceptible. Our proposed studies will determine the effects of very small (ultrafine) outdoor air pollution particles on blood vessel and heart function in people who may have increased susceptibility based on their genetic makeup. Healthy volunteers with and without specific gene mutations will inhale concentrated outdoor ultrafine particles on one occasion, and clean air on another occasion. Detailed measurements of lung, blood vessel, and heart function, and markers of effects in the blood, will be made before and at intervals up to 48 hours after the 2- hour exposure. We expect to see the strongest effects in the subjects with gene mutations that increase susceptibility. These studies will help determine how exposure to air pollution particles contributes to heart and vascular disease, determine whether genetic makeup affects susceptibility, and help to develop strategies to protect the most susceptible people.