Study Title:

Quercetin Helps COPD

Study Abstract

Background: Chronic obstructive pulmonary disease (COPD), induced by chronic cigarette smoke exposure, is characterized by bronchitis, emphysema and irreversible airflow limitation. These changes are thought to be due to oxidative stress and an imbalance of proteases and antiproteases in the lung. Quercetin, a plant flovanoid, has been shown to be a potent antioxidant and anti-inflammatory agent. We therefore hypothesized that quercetin improves lung function in a mouse model of COPD.

Methods: Mice treated with elastase and LPS once a week for 4 weeks show features typical of COPD, including airways inflammation, goblet cell metaplasia, emphysema and decreased lung elasticity. Mice were treated with 0.2-0.5 mg/ml of quercetin dihydrate by lavage needle or 50% propylene glycol (vehicle control) for 5 days and examined for lung function, inflammation, oxidative stress and matrix metalloproteinase (MMP) activity. The effect of quercetin on MMP activity was also examined in LPS-stimulated murine macrophages.

Results. Quercetin treatment improved lung elasticity, reduced airway inflammation and goblet cell metaplasia, and decreased the expression of pro-inflammatory cytokines, chemokines, and muc5AC. Quercetin also increased the SIRT1 levels and decreased the expression levels and activities of MMP9 and MMP12 in vivo and in vitro. Finally, the lungs of quercetin-treated mice also showed decreased levels of thiobarbituric acid reactive substances, a measure of lipid peroxidation caused by oxidative stress.

Conclusions: Quercetin improves lung function in a mouse model of COPD by reducing oxidative stress, inflammation and protease activity.

Study Information

S. Ganesan, PhD, A. Comstock, BS, S. Chattoraj, MS, M.B. Hershenson, MD, U. Sajjan, PhD
Quercetin Improves Lung Inflammation in Mouse Model of COPD by Inhibiting Matrix Metalloproteinases
American Thoracic Society May 2010 annual International Conference in New Orleans
2010 May
Ann Arbor, MI/US

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