Abnormal composition of gut microbiota contributes to delirium-like behaviors after abdominal surgery in mice.

AIMS: Anesthesia and surgery can cause delirium-like symptoms postoperatively. Increasing evidence suggests that gut microbiota is a physiological regulator of the brain. Herein, we investigated whether gut microbiota plays a role in postoperative delirium (POD). METHODS: Mice were separated into non-POD and POD phenotypes after abdominal surgery by applying hierarchical clustering analysis to behavioral tests. Fecal samples were collected, and 16S ribosomal RNA gene sequencing was performed to detect differences in gut microbiota composition among sham, non-POD, and POD mice. Fecal bacteria from non-POD and POD mice were transplanted into antibiotics-induced pseudo-germ-free mice to investigate the effects on behaviors. RESULTS: α-diversity and ß-diversity indicated differences in gut microbiota composition between the non-POD and POD mice. At the phylum level, the non-POD mice had significantly higher levels of Tenericutes, which were not detected in the POD mice. At the class level, levels of Gammaproteobacteria were higher in the POD mice, whereas the non-POD mice had significantly higher levels of Mollicutes, which were not detected in the POD mice. A total of 20 gut bacteria differed significantly between the POD and non-POD mice. Interestingly, the pseudo-germ-free mice showed abnormal behaviors prior to transplant. The pseudo-germ-free mice that received fecal bacteria transplants from non-POD mice but not from POD mice showed improvements in behaviors. CONCLUSIONS: Abnormal gut microbiota composition after abdominal surgery may contribute to the development of POD. A therapeutic strategy that targets gut microbiota could provide a novel alterative for POD treatment.

Celecoxib inhibits Helicobacter pylori-induced invasion of gastric cancer cells through an adenine nucleotide translocator-dependent mechanism.

Cyclooxygenase-2 (COX-2) inhibitor, celecoxib, causes growth inhibition of human gastric carcinoma cells, but it remains unclear whether celecoxib inhibits Helicobacter pylori-induced invasion of gastric cancer cells. The adenine nucleotide translocator (ANT) is a mitochondrial bi-functional protein. We speculate that ANT-dependent pathways might contribute to H. pylori-induced invasion and metastasis of gastric cancer cells. Therefore, in the present study, we evaluate the effect of celecoxib on H. pylori-induced gastric cancer cell motility and invasion. We also explore the role of ANTs in H. pylori-induced gastric cancer cell motility and invasion of gastric cancer cell line AGS. Our results demonstrate that celecoxib induces anoikis-like apoptosis and suppresses the proliferation and invasion of gastric cancer cells induced by H. pylori in culture. RT-PCR and Western blot analysis indicates that celecoxib upregulates the expression of ANT1 and ANT3; however, celecoxib did not increase the expression of ANT2. Our results suggest that celecoxib could be an effective means for suppressing proliferation and invasion of gastric cancer cells induced by H. pylori through an adenine nucleotide translocator-dependent mechanism.