Abstract 9: Early, Single-Dose Post-Burn Estrogen Significantly Decreases Lung Inflammation and Improves Lung Function 7 Days Following Severe Bum Injury
Objective: In patients with severe burn injury, the most common cause of morbidity and mortality is pulmonary dysfunction. We tested estrogen, an anti-oxidant, anti-apoptotic, and anti-inflammatory drug as a potential therapy for mitigation of lung injury and pulmonary dysfunction following severe remote thermal injury.
Methods: 24 rats (8 sham, 8 burn/placebo, 8 burn/17β-estradiol) received a 40% 3° TBSA flank burn, then were administered a single dose of placebo vs 17β-estradiol (0.5 mg/kg) at 15 minutes post-burn. Animals were subjected to pulse oximetry and plethysmography, and lung tissue was analyzed by ELISA for pro-inflammatory cytokines (including IL-6) at 7 days post-injury.
Results: Administration of a single, early dose of 17β-estradiol significantly decreased all measured cytokines. For example, lung tissue levels of IL-6 in those receiving estrogen (150.5 pg/mg) were below those measured in the sham animals (153.8 pg/mg), and were significantly elevated in the placebo animals (571.5 pg/mg) at 7 days post injury. Pulse oximetry of the sham animals remained unchanged from baseline (98% on room air), with estradiol treated animals decreasing mildly (98.1% at baseline to 93.7% at 7 days) and those receiving placebo exhibiting a significant drop in O2 saturation (98.3% at baseline to 83.9% at 7 days). Likewise, minute ventilation in the estrogen-treated animals (113.4 ml/min) was similar to the sham animals (125.5 ml/min), while those animals receiving placebo experienced a significant elevation (368.6 ml/min).
Conclusions: Early, single-dose estrogen administration following severe remote burn injury controlled the IL-6 response in the lung tissue, and significantly preserved lung function at 7 days post-burn.
- © 2010 by American Heart Association, Inc.