Kazuya Ozaki: Laboratory of Microbiology and Infection Control, Division of Biological Sciences, Kyoto Pharmaceutical University, Kyoto 607-8414, Japan.
Hiyo Nagahara: Laboratory of Microbiology and Infection Control, Division of Biological Sciences, Kyoto Pharmaceutical University, Kyoto 607-8414, Japan.
Asaka Kawamura: Laboratory of Microbiology and Infection Control, Division of Biological Sciences, Kyoto Pharmaceutical University, Kyoto 607-8414, Japan.
Takashi Ohgita: Center for Instrumental Analysis, Kyoto Pharmaceutical University, Kyoto 607-8414, Japan. ORCID
Sachika Higashi: Laboratory of Microbiology and Infection Control, Division of Biological Sciences, Kyoto Pharmaceutical University, Kyoto 607-8414, Japan.
Kohei Ogura: Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kyoto 606-8501, Japan.
Hiroyasu Tsutsuki: Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto 860-8556, Japan.
Sunao Iyoda: Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo 162-8640, Japan.
Atsushi Yokotani: Laboratory of Microbiology and Infection Control, Division of Biological Sciences, Kyoto Pharmaceutical University, Kyoto 607-8414, Japan.
Toshiyuki Yamaji: Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Tokyo 162-8640, Japan.
Joel Moss: Clinical Care Medicine and Pulmonary Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20824-0105, USA.
Kinnosuke Yahiro: Laboratory of Microbiology and Infection Control, Division of Biological Sciences, Kyoto Pharmaceutical University, Kyoto 607-8414, Japan.
is an important foodborne pathogen. Cholix cytotoxin (Cholix), produced by , is a novel eukaryotic elongation factor 2 (eEF2) adenosine diphosphate ribosyltransferase that causes host cell death by inhibiting protein synthesis. However, the role of Cholix in the infectious diseases caused by remains unclear. Some bacterial cytotoxins are carried by host extracellular vesicles (EVs) and transferred to other cells. In this study, we investigated the effects of EV inhibitors and EV-regulating proteins on Cholix-induced hepatocyte death. We observed that Cholix-induced cell death was significantly enhanced in the presence of EV inhibitors (e.g., dimethyl amiloride, and desipramine) and Rab27a-knockdown cells, but it did not involve a sphingomyelin-dependent pathway. RNA sequencing analysis revealed that desipramine, imipramine, and EV inhibitors promoted the Cholix-activated c-Jun NH2-terminal kinase (JNK) pathway. Furthermore, JNK inhibition decreased desipramine-enhanced Cholix-induced poly (ADP-ribose) polymerase (PARP) cleavage. In addition, suppression of Apaf-1 by small interfering RNA further enhanced Cholix-induced PARP cleavage by desipramine. We identified a novel function of desipramine in which the stimulated JNK pathway promoted a mitochondria-independent cell death pathway by Cholix.
