Pre-protective effect of lipoic acid on injury induced by H2O2 in IPEC-J2 cells

Alpha-lipoic acid (LA) is considered to be a universal antioxidant. The intestine is very sensitive to a wide range of stressors for it exposed in a complex microenvironment that usually contained excess free radicals. The objective of this study was to evaluate the pre-protective effect of LA on intestinal epithelial cell injury induced by H2O2. In this research, IPEC-J2 cells were divided into three groups: the control group, the H2O2-treated group, and the LA pre-protective group. Cell viability, intracellular ROS, DNA damage integrity, and antioxidant enzyme activity of all groups were measured. Quantitative reverse transcription-PCR was used to determine the influence of oxidative stress and LA on the GH/IGF-1 axis in IPEC-J2 cells. The research selected 1 mM H2O2 and 10 μg/ml as modeling concentration. The data indicated that H2O2 can significantly increase the intracellular free radicals, leading to serious DNA damage and significantly reduce superoxide dismutase, glutathione peroxidase, catalase, and lipase activity. LA-protected IPEC-J2 cells against H2O2-induced injury by scavenging hydroxyl radical. In the current study, LA pre-protective group share a lower intracellular ROS and lower DNA damage compare to H2O2-treated group (P < 0.01); and also, a higher lipase activity were detected in LA pre-protective group compare to H2O2-treated group (P < 0.05). But the mechanism between oxidative stress, LA effect, and GH/IGF-1 axis is still unknown. The model used in the current study is also suitable for other feed additive screening.