Nigella Sativa Essential Oil Prevents Airway Inflammation in Ovalbumin Sensitized Guinea-pigs

Objectives: Nigella sativa has been investigated as an adjuvant and prophylactic agent for asthma. This study was planned to investigate the effect of Nigella sativa essential oil on guinea pig model of allergic airway inflammation. Methods: In this study conducted at PGMI, Lahore, eighteen guinea pigs were divided into three groups. Disease Control (DC) and Nigella sativa (NS) group were sensitized with intraperitoneal injection of ovalbumin on day 0 and 14 and then challenged with inhalation of 1% ovalbumin on days 22, 23 and 24. Normal control (NC) was given equivalent treatment with phosphate buffer saline (PBS). NS group was given 5 mg/kg Nigella sativa oil orally before every intranasal challenge. At the end of study, blood and bronchoalveolar lavage (BAL) samples were collected for estimation of total leukocyte counts (TLC), differential leukocyte counts (DLC) and eosinophil percentage. Results: Both sensitized groups had significantly raised TLC in both blood and BAL fluid. Nigella sativa treatment lowered TLC in blood insignificantly but highly significantly in BAL fluid. Similarly, eosinophil percentage was significantly high in both sensitized groups and Nigella sativa treatment was able to affect a highly significant reduction in both blood and BAL fluid. Conclusion: Nigella sativa reduces airway inflammation when used before allergic airway challenge. It may be considered as a prophylactic agent to asthma therapy.