Appropriate kit

Oxidative stress was evaluated with reactive oxygen species (ROS) and malondialdehyde (MDA) generation and antioxidant enzymes (total antioxidant capacity, T-AOC; superoxide Dismutase, SOD; total Glutathione S-transferase, TGST). The A549 cells in the inner chamber of each group were harvested and lysed by ultrasonication in the presence of a protease inhibitor. The supernatant was collected for analysis after centrifugation at 14,000 × g for 5 min. The levels of MDA, T-AOC, SOD and TGST in the supernatant were measured using appropriate kits (Beyotime, China) following the manufacturer's instructions.
ROS was measured using the DCFH-DA ROS assay kit (Beyotime, China). Cells were labeled with a 10 µM probe (2,7-dichlorofluorescin-diacetate, DCFH-DA) at 37° C for 30 min in the dark. Then, the cells were washed with PBS and analyzed on an enzyme-labeled instrument by a fluorescence spectrophotometer with an excitation wavelength (488 nm) and an emission wavelength (530 nm).

The intestinal tissues were homogenized and centrifuged at 12000 × g for 15 min before collecting the supernatant for spectrophotometric investigation. Protein concentrations were determined using the BCA assay kit. The concentrations of MDA and activities of SOD were detected using the appropriate kits (Beyotime Biotech, Inc., Jiangsu, China) and according to the manufacturer's instructions.

Serum was collected from each blood sample after centrifugation at 800 × g for 15 min. According to the pretest results, the serum was diluted 4-fold, and the IL-22 levels in each serum sample were then examined using mouse the IL-22 ELISA kits (Thermo Fisher Scientific) according to the manufacturer's instructions.
In addition, aortas were lysed with RIPA lysis buffer, and the supernatants were collected and quantified. Then, the malondialdehyde (MDA) level, glutathione (GSH) level, and SOD activity in each sample were measured using the appropriate kits (all from Beyotime Biotechnology) according to the manufacturers' instructions.