Highlights The glutathione cycle in AGS cells were downregulated by H. pylori infection. The GSH level was reduced in AGS cells infected with H. pylori. The declined GSH level was greater in H. pylori gastric cancer strain infection.

TakashiToyonaga has received a portion of the sales of Flush knife-BT and Flush Knife-BTS, which were developed in collaboration with FUJIFILM Medical Co., Ltd., as royalties. He has also received a portion of the sales of Coagrasper G, which were developed in collaboration with Olympus Corporation, as royalties. The other authors have no conflicts of interest or financial ties to disclose.