Chamomile flowers extract protects against thinner inhalation-induced lung toxicity via attenuating cytochrome P2E1 activity, surfactant deficiency, and alveolar structural injury in rats

Abstract Background Lungs are adversely affected by repeated exposure to thinner fumes. This study aimed to examine the pulmonary toxic effects of chronic thinner inhalation and the possible protection by chamomile administration. Adult male Wistar rats were exposed to thinner fumes for 8 weeks (4 h/day, 6 days/week), while chamomile flower extract (400 mg/kg body weight) was given orally during thinner exposure for the same period. Results The study showed lung damage following chronic thinner exposure through increased cytochrome P2E1 (CYP2E1), superoxide anion (O 2 •− ), hydrogen peroxide (H 2 O 2 ), and malondialdehyde (MDA), with decreased antioxidant enzymes; superoxide dismutase (SOD), and catalase (CAT). Moreover, an elevation of lung enzymes; alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT), and lactate dehydrogenase (LDH) with depletion in total protein and albumin contents in serum and bronchoalveolar lavage fluid were observed. Thinner exposure also exhibited increased lung deoxyribonucleic acid (DNA) damage, transforming growth factor-β1 (TGF-β1), insulin-like growth factor-1 (IGF-1), hydroxyproline (HYP), and collagen type 1 (COL-1), with decreased serum surfactant protein-A (SP-A), total and differential leukocytes (WBCs) count, except for neutrophils. Histological investigations revealed deteriorative changes along with accumulated collagen fibers affecting the lung and other respiratory organs. Conclusion Supplementation of chamomile extract succeeded in preventing thinner-induced lung oxidative stress, enzyme leakage, surfactant deficiency, DNA damage, fibrosis, and histological injury. Therefore, consumption of chamomile extract could be recommended for alleviating thinner-induced health hazards and lung toxicity.