Environmental Determinants of Lung Aging

This chapter reviews the interaction of various environmental factors with the aging lung. In general, environmental factors enhance aging effects which, in turn, lead to clinical disease in susceptible subjects. The lung has a remarkable array of responses and defenses to oxidative stress. Age-related changes in antioxidant defenses include decreased lung tissue ascorbic acid and reduction of glutathione. A progressive reduction in antioxidant defenses might contribute to the decline of FEV and increased risk for emphysema with increasing age. Some particulates, such as cigarette smoke, coal dust and silica, have intrinsic free radical activity. Others, such as diesel emissions, contain compounds that catalyze the generation of reactive oxygen species (ROS) and most exogenous toxins activate lung resident cells to produce ROS. Many of these agents have been associated with accelerated decline in.