Serine prevents LPS-induced intestinal inflammation and barrier damage via p53-dependent glutathione synthesis and AMPK activation

The role of serine in metabolic processes has recently attracted much attention as it could be used for the biosynthesis of purine, sphingolipids, and glutathione. The present study was conducted to investigate the effects of serine on LPS-induced intestinal inflammation and barrier dysfunction. The results showed that pretreatment with serine prevented the LPS-induced inflammatory response and oxidative stress both in vivo and in vitro. Moreover, serine maintained intestinal barrier function and permeability. In addition, we found that serine improved glutathione synthesis and AMP-activated protein kinase (AMPK) activity. However, following the small interfering RNA (siRNA) inhibition of p53 expression or inhibition of glutathione synthesis in IPEC-1 cells, the protective effects of serine on LPS-induced damage were diminished. Our results indicated that serine may prevent LPS-induced damage in the intestine by improving glutathione synthesis and AMPK activity in a p53-dependent manner.