DIETARY FLAXSEED SUPPLEMENTATION PROTECTS AGAINST ACUTE LUNG INJURY AND INFLAMMATION IN MICE

Abstract

Background Flaxseed, a nutritional supplement, has high contents of omega-3 fatty acids and lignans with known anti-inflammatory and anti-oxidant properties. Its use in acute lung disease has never been evaluated. In this study we tested flaxseed (FS) diets in three experimental murine models of acute lung injury (ALI). Methods Mice were fed 10% FS for several weeks to determine kinetics of lignan accumulation in blood using liquid chromatography tandem mass spectrometry. Mice fed control and 10% FS diets were challenged by Hyperoxia (80% O2), intratracheal (i.t.) LPS or acid aspiration (AA). Bronchoalveolar lavage (BAL) was evaluated for white blood cells (WBC), neutrophils (PMN), and proteins 24 hours post i.t. challenge of acid or LPS or 6 days after hyperoxia. Lung lipid peroxidation was determined by malondialdehyde (MDA) tissue levels. Results Plasma FS lignans, enterodiol and enterolactone, peaked in the first week and decreased to steady state by 2–3 weeks. Following hyperoxia, FS mice showed a significant decrease in BAL proteins, a measure of lung edema, and a trend with AA while lung inflammation and MDA levels were significantly decreased in both models. In strong contrast, LPS injury and inflammation was not ameliorated by FS. Remarkably, serum lignan levels decreased dramatically in both AA and hyperoxic mice but not in LPS mice. Conclusion Dietary FS is protective against experimental ALI, inflammation and lung lipid peroxidation in vivo. Funded by: AICR (MCS), NIH-HL64063 (YA), U. Penn Research Foundation (MCS, YA).