Effects of L-2-oxоthiazolidine-4-carboxylic acid on the lung antioxidant defense system in an asthma mouse model

Aim: We aimed to study the effect of a glutathione precursor, L-2-охоthiazolidine-4-carboxylic acid (OTCA), on the lung antioxidant defense system in an animal asthma model. Materials and methods: The study was carried out on 24 female C57BL/6 mice. The mice were divided into 4 treatment groups: group 1 – control group; group 2 – injected with ovalbumin (OVA) and given an OVA inhalant; group 3 –treated with OTCA and phosphate-buffered saline inhalant; and group 4 – injected with OVA and OTCA and givenan OVA inhalant. Under sodium pentobarbital anesthesia the animals were killed by exsanguination 48 h after the lastinhalation to obtain a lung homogenate. The activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GP) and the content of nonprotein sulfhydryl (NPSH) groups in lung homogenate were investigated. Results: OVA decreased the activities of SOD (P = 0.007), CAT (P = 0.004), and GP (P = 0.05) and the NPSH content (P = 0.0008) in the lung homogenate compared with the control animals. Treatment with OVA and OTCA (group 4) resulted in a significant increase in the activities of CAT (P = 0.01) and GP (P = 0.05) and the NPSH content (P = 0.002) compared to the OVA group (group 2). Conclusion: OTCA (160 mg/kg) restored the activities of basic enzymes in the lung antioxidant defense system in an OVA-induced asthma mouse model 48 h after the last nebulization.