Pulmonary responses to acute ozone exposure in fasted mice: effect of leptin administration

290: L856–L865, 2006. First published December 22, 2005; doi:10.1152/ajplung.00386.2005.—Epidemiological studies indicate the incidence of asthma is increased in obese and overweight humans. Responses to ozone (O3), an asthma trigger, are increased in obese (ob/ob) mice lacking the satiety hormone leptin. The long form of leptin receptor (Ob-Rb) is required for satiety; mice lacking this receptor (db/db mice) are also substantially obese. Here, wild-type (WT) and db/db mice were exposed to air or O3 (2 ppm) for 3 h. Airway responsiveness, measured by the forced oscillation technique, was greater in db/db than WT mice after air exposure. O3-induced increases in pulmonary resistance and airway responsiveness were also greater in db/db mice. BALF eotaxin, IL-6, KC, and MIP-2 increased 4 h after O3 exposure and subsided by 24 h, whereas protein and neutrophils continued to increase through 24 h. For each outcome, the effect of O3 was significantly greater in db/db than WT mice