Malonedialdehyde
Concentrations of MDA in mucosa of the duodenum and liver, as an index of lipid peroxidation, were analyzed using an ELISA kit (STA-330; Cell Biolabs) as described by Zhao et al. (2013). Mucosa samples (150 mg) of the duodenum and liver (150 mg) were weighed and suspended into 0.6 mL PBS containing 0.05% butylated hydroxytoluene. The homogenate was prepared as mentioned in the TAC analysis. The supernatant was used to determine concentrations of MDA and protein concentrations. Protein concentrations were determined using a commercial kit (Thermo Fisher Scientific Inc.; Shen et al., 2012b). Concentrations of MDA were expressed as micromoles/gram protein