Lipid peroxidation changes induced by dibutyl phthalate in allergic asthma mice

BackgroundDibutyl phthalate (DBP) is a common plasticizer in daily life and has been proved to be related to the exacerbation of allergic asthma. Domestic and foreign studies have shown that lipid peroxidation is closely related to the severity of asthma, which can be used as a basis for the diagnosis and treatment of asthma. Whether DBP can induce lipid peroxidation in allergic asthma remains to be further studied.ObjectiveTo investigate whether DBP aggravates allergic asthma by inducing lipid peroxidation in allergic asthma mice.MethodsEighty male BALB/c mice were randomly divided into 4 groups, namely control group, DBP group (40 mg·kg−1), 50 μg ovalbumin (OVA) group (allergic asthma model group), and DBP+OVA group. The DBP group and the DBP+OVA group were given DBP by gavage from Day 1 to 28, and the OVA group and the DBP+OVA group were sensitized by intraperitoneal injection of OVA, once every 3 d, a total of 5 injections, from Day 9 to 21. From Day 29 to 35, the OVA group and the DBP+OVA group were challenged by OVA atomization. After the exposure, samples of blood and lung were collected. The airway hyperresponsiveness of mice was observed by lung function analysis. The serum contents of immunoglobulin E (IgE), OVA-specific immunoglobulin E (OVA-IgE), and lung homogenate levels of interleukin 4 (IL-4) were detected by enzyme-linked immunosorbent assay (ELISA) to evaluate airway allergic inflammation. The pathological changes of lung tissues were observed after hematoxylin-eosin (HE) staining and collagen fiber (Masson) staining. The contents of reactive oxygen species (ROS), lipid ROS, glutathione peroxidase 4 (GPX4), reduced glutathione (GSH), malondialdehyde (MDA), and 4-hydroxynonenal (4-HNE) in lung homogenates were detected by ELISA to evaluate lipid peroxidation.ResultsThe results of lung function analysis showed that compared with the control group, the inspiratory resistance (Ri) and expiratory resistance (Re) of the OVA group and the DBP+OVA group were increased, and the lung compliance (Cldyn) was decreased. The DBP + OVA group was more severe, and the difference between the OVA group and the DBP + OVA group was statistically significant (P