Ellagic Acid Ameliorates Lung Inflammation and Heart Oxidative Stress in Elastase-Induced Emphysema Model in Rat

Chronic obstructive pulmonary disease (COPD) is one of the most important factors in the progress of cardiovascular disease (CVD) which is associated with limited airflow and alveolar demolition. The aim of this study is to investigate the possible protective effect of ellagic acid (EA), as a natural anti-oxidant, against pulmonary arterial hypertension (PAH) and development of lung and heart injuries induced by elastase. Sixty healthy male Sprague-Dawley rats (150-180 g) were divided into six groups: control (saline 0.9%, 1 ml/kg, by gavage), porcine elastase (PPE) (25 UI/kg, intratracheal), EA (10, 15, and 30 mg/kg, gavage), PPE + EA (30 mg/kg, by gavage). Lead II electrocardiogram was used to evaluate the inotropic and chronotropic parameters of rat heart using Bio-Amp device and the LabChart software. The anti-oxidant levels (superoxide dismutase, catalase, and glutathione) and malondialdehyde were measured by appropriate kits, and right ventricular systolic pressure (RVSP) was recorded by the PowerLab system and measured by the LabChart software (ADInstruments). Elastase administration caused an increase in RVSP which was in line with elevated inflammatory cells and cytokines, as well as lipid peroxidation, and decreased anti-oxidant levels. Also, electrocardiogram parameters significantly changed in elastase group compared with control rats. Co-treatment with EA not only restored elastase-depleted anti-oxidant levels and prevented pulmonary arterial hypertension but also improved cardiac chronotropic and inotropic properties. Our results documented that elastase administration leads to pulmonary arterial hypertension and EA, as an anti-inflammatory and anti-oxidant factor, can protect development of lung and heart injuries induced by elastase.