著者
Kentaro Matsumoto Shenwei Ni Hiroyuki Arai Takashi Toyama Yoshiro Saito Takehiro Suzuki Naoshi Dohmae Kojiro Mukai Tomohiko Taguchi
出版者
Japan Society for Cell Biology
雑誌
Cell Structure and Function (ISSN:03867196)
巻号頁・発行日
vol.48, no.1, pp.59-70, 2023 (Released:2023-02-16)
参考文献数
43

Stimulator of interferon genes (STING) is an ER-localized transmembrane protein and the receptor for 2',3'-cyclic guanosine monophosphate–adenosine monophosphate (cGAMP), which is a second messenger produced by cGAMP synthase (cGAS), a cytosolic double-stranded DNA sensor. The cGAS-STING pathway plays a critical role in the innate immune response to infection of a variety of DNA pathogens through the induction of the type I interferons. Pharmacological activation of STING is a promising therapeutic strategy for cancer, thus the development of potent and selective STING agonists has been pursued. Here we report that mouse STING can be activated by phenylarsine oxide (PAO), a membrane permeable trivalent arsenic compound that preferentially reacts with thiol group of cysteine residue (Cys). The activation of STING with PAO does not require cGAS or cGAMP. Mass spectrometric analysis of the peptides generated by trypsin and chymotrypsin digestion of STING identifies several PAO adducts, suggesting that PAO covalently binds to STING. Screening of STING variants with single Cys to serine residues (Ser) reveals that Cys88 and Cys291 are critical to the response to PAO. STING activation with PAO, as with cGAMP, requires the ER-to-Golgi traffic and palmitoylation of STING. Our results identify a non-nucleotide STING agonist that does not target the cGAMP-binding pocket, and demonstrate that Cys of STING can be a novel target for the development of STING agonist.Key words: STING agonist, cysteine modification, innate immunity, phenylarsine oxide
著者
Takashi Toyama Gi-Wook Hwang Akira Naganuma
出版者
一般社団法人日本毒性学会
雑誌
Fundamental Toxicological Sciences (ISSN:2189115X)
巻号頁・発行日
vol.2, no.5, pp.227-228, 2015-12-09 (Released:2015-12-09)
参考文献数
5
被引用文献数
1 1

This study attempted to identify substances that are driven out of HEK293 cells by methylmercury. Metabolomic analysis revealed that the levels of 3-phenylpropionic acid, citrulline, lactic acid, ornithine, proline and beta-alanine in the cell culture medium were increased by the treatment of cells with methylmercury. Address to the mechanism underlying the release of these substances will provide useful information to elucidate the toxicity mechanism of methylmercury.
著者
Yo Shinoda Masahiro Akiyama Takashi Toyama
出版者
The Pharmaceutical Society of Japan
雑誌
Biological and Pharmaceutical Bulletin (ISSN:09186158)
巻号頁・発行日
vol.46, no.9, pp.1162-1168, 2023-09-01 (Released:2023-09-01)
参考文献数
109

Methylmercury (MeHg) is the causal substrate of Minamata disease and a major environmental toxicant. MeHg is widely distributed, mainly in the ocean, meaning its bioaccumulation in seafood is a considerable problem for human health. MeHg has been intensively investigated and is known to induce inflammatory responses and neurodegeneration. However, the relationship between MeHg-induced inflammatory responses and neurodegeneration is not understood. In the present review, we first describe recent findings showing an association between inflammatory responses and certain MeHg-unrelated neurological diseases caused by neurodegeneration. In addition, cell-specific MeHg-induced inflammatory responses are summarized for the central nervous system including those of microglia, astrocytes, and neurons. We also describe MeHg-induced inflammatory responses in peripheral cells and tissue, such as macrophages and blood. These findings provide a concept of the relationship between MeHg-induced inflammatory responses and neurodegeneration, as well as direction for future research of MeHg-induced neurotoxicity.
著者
Mayuka Yamada Midori Suzuki Takuya Noguchi Takumi Yokosawa Yuto Sekiguchi Natsumi Mutoh Takashi Toyama Yusuke Hirata Gi-Wook Hwang Atsushi Matsuzawa
出版者
The Pharmaceutical Society of Japan
雑誌
BPB Reports (ISSN:2434432X)
巻号頁・発行日
vol.3, no.1, pp.16-21, 2020 (Released:2020-11-26)
参考文献数
27
被引用文献数
4 7

Both NF-E2-related factor 2 (Nrf2) and heat shock protein 70 (HSP70) contribute to cellular defense to various stresses, and have emerged as candidates of therapeutic targets to improve or prevent tissue damage. Cefotaxime (CTX), a third-generation cephalosporin antibiotic, is conceived as a safe drug largely free from side effects. CTX exhibits broad-spectrum antimicrobial activity, and thereby, is most commonly prescribed for the treatment of infectious diseases induced by Gram-positive or Gram-negative bacteria. In this study, we unexpectedly found the beneficial properties of CTX that upregulate both Nrf2 and HSP70 to the extent that stress-induced damage is ameliorated. Non-toxic levels of reactive oxygen species (ROS) induced by CTX activated the Nrf2 pathway without cytotoxicity, which in turn upregulated HSP70. Interestingly, the cytotoxicity of Fas/CD95 ligand (FasL), a cytotoxic cytokine that strongly induces apoptosis, was significantly ameliorated by pre-treatment with CTX, most likely because of the upregulation of Nrf2 and HSP70. Our results therefore show novel properties of CTX, which raise the possibility that CTX works as a non-toxic therapeutic agent for preventing and repairing tissue damage.
著者
Kentaro Matsumoto Shenwei Ni Hiroyuki Arai Takashi Toyama Yoshiro Saito Takehiro Suzuki Naoshi Dohmae Kojiro Mukai Tomohiko Taguchi
出版者
Japan Society for Cell Biology
雑誌
Cell Structure and Function (ISSN:03867196)
巻号頁・発行日
pp.22085, (Released:2022-12-28)

Stimulator of interferon genes (STING) is an ER-localized transmembrane protein and the receptor for 2’,3’-cyclic guanosine monophosphate&endash;adenosine monophosphate (cGAMP), which is a second messenger produced by cGAMP synthase (cGAS), a cytosolic double-stranded DNA sensor. The cGAS-STING pathway plays a critical role in the innate immune response to infection of a variety of DNA pathogens through the induction of the type I interferons. Pharmacological activation of STING is a promising therapeutic strategy for cancer, thus the development of potent and selective STING agonists has been pursued. Here we report that mouse STING can be activated by phenylarsine oxide (PAO), a membrane permeable trivalent arsenic compound that preferentially reacts with thiol group of cysteine residue (Cys). The activation of STING with PAO does not require cGAS or cGAMP. Mass spectrometric analysis of the peptides generated by trypsin and chymotrypsin digestion of STING identifies several PAO adducts, suggesting that PAO covalently binds to STING. Screening of STING variants with single Cys to serine residues (Ser) reveals that Cys88 and Cys291 are critical to the response to PAO. STING activation with PAO, as with cGAMP, requires the ER-to-Golgi traffic and palmitoylation of STING. Our results identify a non-nucleotide STING agonist that does not target the cGAMP-binding pocket, and demonstrate that Cys of STING can be a novel target for the development of STING agonist.Key words: STING agonist, cysteine modification, innate immunity, phenylarsine oxide