PTGS2 and chronic atrophic gastritis: The results of the in vivo experiment showed that Atractylodes lactone I could improve chronic atrophic gastritis (CAG) in model rats with the expression of heat shock protein 70 (HSP70), could reduce the content of interleukin-8 (IL-8), and could reduce the protein expression of nuclear transcription factor-κB (NF-κB) and cyclooxygenase-2 (COX-2), thus reducing inflammation factors in gastric mucosal injury (Li et al., 2016b).