LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 10 of total 74

Search options

  1. Article ; Online: Gingipain-carrying outer membrane vesicles from Porphyromonas gingivalis cause barrier dysfunction of Caco-2 cells by releasing gingipain into the cytosol.

    Nonaka, Saori / Okamoto, Rin / Katsuta, Yui / Kanetsuki, Shiori / Nakanishi, Hiroshi

    Biochemical and biophysical research communications

    2024  Volume 707, Page(s) 149783

    Abstract: Ingestion of Porphyromonas gingivalis, a periodontal pathogen, disrupts the intestinal barrier in mice. However, the involvement of outer membrane vesicles (OMVs) secreted from P. gingivalis in the destruction of the intestinal barrier remains unclear. ... ...

    Abstract Ingestion of Porphyromonas gingivalis, a periodontal pathogen, disrupts the intestinal barrier in mice. However, the involvement of outer membrane vesicles (OMVs) secreted from P. gingivalis in the destruction of the intestinal barrier remains unclear. In this study, we tested the hypothesis that OMVs carrying gingipains, the major cysteine proteases produced by P. gingivalis, affects the intestinal barrier function. OMVs increased the permeability of the Caco-2 cell monolayer, a human intestinal epithelial cell line, accompanied by degradation of the tight junction protein occludin. In contrast, OMVs prepared from mutant strains devoid of gingipains failed to induce intestinal barrier dysfunction or occludin degradation in Caco-2 cells. A close histological examination revealed the intracellular localization of gingipain-carrying OMVs. Gingipain activity was detected in the cytosolic fraction of Caco-2 cells after incubation with OMVs. These results suggest that gingipains were internalized into intestinal cells through OMVs and transported into the cytosol, where they then directly degraded occludin from the cytosolic side. Thus, P. gingivalis OMVs might destroy the intestinal barrier and induce systemic inflammation via OMV itself or intestinal substances leaked into blood vessels, causing various diseases.
    MeSH term(s) Animals ; Mice ; Humans ; Gingipain Cysteine Endopeptidases/metabolism ; Caco-2 Cells ; Porphyromonas gingivalis/physiology ; Cytosol/metabolism ; Occludin/metabolism ; Adhesins, Bacterial/metabolism
    Chemical Substances Gingipain Cysteine Endopeptidases ; Occludin ; Adhesins, Bacterial
    Language English
    Publishing date 2024-03-13
    Publishing country United States
    Document type Journal Article
    ZDB-ID 205723-2
    ISSN 1090-2104 ; 0006-291X ; 0006-291X
    ISSN (online) 1090-2104 ; 0006-291X
    ISSN 0006-291X
    DOI 10.1016/j.bbrc.2024.149783
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  2. Article ; Online: How to Deal With the Risk of Evacuation of Psychiatric Hospital in Nuclear Disaster: A Case Study.

    Hori, Arinobu / Sawano, Toyoaki / Nonaka, Saori / Tsubokura, Masaharu

    Disaster medicine and public health preparedness

    2023  Volume 17, Page(s) e332

    Abstract: Objective: People with psychiatric disorders are one of the most vulnerable populations in disasters, and the 2011 Great East Japan Earthquake reported higher post-evacuation mortality rates among psychiatric inpatients. A psychiatric hospital evacuated ...

    Abstract Objective: People with psychiatric disorders are one of the most vulnerable populations in disasters, and the 2011 Great East Japan Earthquake reported higher post-evacuation mortality rates among psychiatric inpatients. A psychiatric hospital evacuated after the nuclear accident was surveyed to gain valuable insights for future disaster preparedness.
    Methods: The authors interviewed two Odaka Akasaka Hospital (a private psychiatric hospital) staff responsible for evacuation due to the nuclear accident.
    Results: At the time of the earthquake, 104 patients had been admitted to the hospital. They were instructed to evacuate on the grounds that they existed within a 20 km radius of Fukushima Daiichi Nuclear Power Station. Although the evacuation process was extraordinarily demanding, the staff acted professionally, and no patient experienced a significant deterioration in health during the evacuation.
    Conclusion: It was reasonable to follow the evacuation order because of the difficulty of obtaining accurate information about radiation exposure and staff availability in high-risk situations. The staff's knowledgeable and attentive care of the patients was one of the factors that enabled them to successfully carry out this severe evacuation. However, this may be related to the high mortality rate after the evacuation of patients who were separated from such caregivers.
    MeSH term(s) Humans ; Hospitals, Psychiatric ; Fukushima Nuclear Accident ; Disasters ; Earthquakes ; Japan
    Language English
    Publishing date 2023-02-23
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2375268-3
    ISSN 1938-744X ; 1935-7893
    ISSN (online) 1938-744X
    ISSN 1935-7893
    DOI 10.1017/dmp.2022.298
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  3. Article ; Online: Human β-Defensin 3 Inhibits

    Inoue, Erika / Minatozaki, Shiyo / Katsuta, Yui / Nonaka, Saori / Nakanishi, Hiroshi

    International journal of molecular sciences

    2022  Volume 23, Issue 23

    Abstract: Recently, the effects of antibacterial peptides are suggested to have therapeutic potential in Alzheimer's disease. Furthermore, systemic treatment ... ...

    Abstract Recently, the effects of antibacterial peptides are suggested to have therapeutic potential in Alzheimer's disease. Furthermore, systemic treatment of
    Language English
    Publishing date 2022-12-01
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2019364-6
    ISSN 1422-0067 ; 1422-0067 ; 1661-6596
    ISSN (online) 1422-0067
    ISSN 1422-0067 ; 1661-6596
    DOI 10.3390/ijms232315099
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  4. Article ; Online: Secreted gingipains from Porphyromonas gingivalis increase permeability in human cerebral microvascular endothelial cells through intracellular degradation of tight junction proteins.

    Nonaka, Saori / Kadowaki, Tomoko / Nakanishi, Hiroshi

    Neurochemistry international

    2022  Volume 154, Page(s) 105282

    Abstract: Despite a clear correlation between the infiltration of periodontal pathogens in the brain and cognitive decline in Alzheimer's disease (AD), the precise mechanism underlying bacteria crossing the blood-brain barrier (BBB) remains unclear. The ... ...

    Abstract Despite a clear correlation between the infiltration of periodontal pathogens in the brain and cognitive decline in Alzheimer's disease (AD), the precise mechanism underlying bacteria crossing the blood-brain barrier (BBB) remains unclear. The periodontal pathogen Porphyromonas gingivalis produces a unique class of cysteine proteases termed gingipains. Gingipains appear to be key virulence factors that exacerbate sporadic AD. We herein report that gingipains are involved in increasing permeability of hCMEC/D3 cell monolayer, human cerebral microvascular endothelial cell lines, through degradation of tight junction proteins including Zonula occludens-1 (ZO-1) and occludin. There was a significant decrease in the mean protein levels of ZO-1 and occludin after infection of hCMEC/D3 cells with wild-type (WT) P. gingivalis. However, infection of these cells with a gingipain-deficient P. gingivalis strain showed significantly lower reduction of the mean protein levels of either ZO-1 and occludin, compared to the WT strain. Similar results were obtained after treatment with culture supernatant from WT and gingipain-deficient P. gingivalis strains. In vitro digestion of human recombinant ZO-1 and occludin by WT P. gingivalis culture supernatant in the absence or presence of gingipain inhibitors indicated that gingipains directly degraded these tight junction proteins. A close immunohistochemical examination using anti-gingipain antibody further revealed that gingipains localized in the cytosol and nuclei of hCMEC/D3 cells after infection with WT P. gingivalis and treatment with its culture supernatant. Furthermore, intracellular localization of outer membrane vesicles (OMVs) bound gingipains from WT P. gingivalis and OMV-induced degradation of ZO-1 and occludin were also observed in hCMEC/D3 cells. Thus, the delivery of gingipains into the cerebral microvascular endothelial cells, probably through OMV, may be responsible for the BBB damage through intracellular degradation of ZO-1 and occludin.
    MeSH term(s) Adhesins, Bacterial/metabolism ; Endothelial Cells/metabolism ; Gingipain Cysteine Endopeptidases ; Humans ; Permeability ; Porphyromonas gingivalis/metabolism ; Tight Junction Proteins
    Chemical Substances Adhesins, Bacterial ; Gingipain Cysteine Endopeptidases ; Tight Junction Proteins
    Language English
    Publishing date 2022-01-13
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 283190-9
    ISSN 1872-9754 ; 0197-0186
    ISSN (online) 1872-9754
    ISSN 0197-0186
    DOI 10.1016/j.neuint.2022.105282
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  5. Article ; Online: Secreted gingipains from Porphyromonas gingivalis induce microglia migration through endosomal signaling by protease-activated receptor 2.

    Nonaka, Saori / Nakanishi, Hiroshi

    Neurochemistry international

    2020  Volume 140, Page(s) 104840

    Abstract: Much attention has been paid to the connection between periodontitis and Alzheimer's disease (AD). We previously showed that infection of P. gingivalis, one of major periodontal pathogen causing periodontitis, induced migration and inflammatory responses ...

    Abstract Much attention has been paid to the connection between periodontitis and Alzheimer's disease (AD). We previously showed that infection of P. gingivalis, one of major periodontal pathogen causing periodontitis, induced migration and inflammatory responses in murine microglia through gingipain-induced activation of protease-activated receptor 2 (PAR2). In this study, we have attempted to clarify effects of secreted gingipains on cell migration of human microglial cell line, cleavage sites of PAR2 by gingipains and subsequent signaling pathways. P. gingivalis culture supernatant induced migration and membrane ruffling, which is necessary for microglia migration, in human microglial cell line HMC3 cells through PAR2. These effects were mainly mediated by gingipains, because cell migration and membrane ruffling were dramatically inhibited by treatment with gingipain inhibitors. Furthermore, pharmacological and genetic inhibition of Src kinase and β-arrestin, which are important for the internalization of G protein-coupled receptors, significantly inhibited P. gingivavlis culture supernatant-induced membrane ruffling in HMC3 cells. After treatment with P. gingivalis culture supernatant in Flag-PAR2-HA transfected HEK293T cells, Flag was removed from the cell surface, and HA was detected in the cytosol, indicating the internalization of PAR2. Furthermore, the phosphorylation level of ERK1/2 increased in PAR2-transfected HEK293T cells after treatment with P. gingivalis culture supernatant. The gingipain inhibitors, Src kinase inhibitor and β-arrestin knockdown suppressed PAR2 internalization and ERK1/2 phosphorylation. These observations suggest that secreted gingipains from P. gingivalis induce Src- and β-arrestin-dependent internalization of PAR2 and further activate the ERK1/2 pathway to promote migration of microglia. PAR2 are activated by the tethered ligands exposed by cleavage of extracellular N-terminal of PAR2. We also estimated potential gingipain cleavage sites in PAR2 and exposed tethered ligands, which are required for PAR2 internalization and membrane ruffling. The identified mechanism in this study might contribute to the retrogression of sporadic AD in patients after infection with P. gingivalis.
    MeSH term(s) Amino Acid Sequence ; Cell Movement/physiology ; Endosomes/genetics ; Endosomes/metabolism ; Gingipain Cysteine Endopeptidases/genetics ; Gingipain Cysteine Endopeptidases/metabolism ; HEK293 Cells ; Humans ; Microglia/metabolism ; Porphyromonas gingivalis/genetics ; Porphyromonas gingivalis/metabolism ; Receptor, PAR-2/genetics ; Receptor, PAR-2/metabolism ; Signal Transduction/physiology
    Chemical Substances Gingipain Cysteine Endopeptidases ; Receptor, PAR-2
    Language English
    Publishing date 2020-08-25
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 283190-9
    ISSN 1872-9754 ; 0197-0186
    ISSN (online) 1872-9754
    ISSN 0197-0186
    DOI 10.1016/j.neuint.2020.104840
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  6. Article ; Online: Utility of PERMA-profiler in association with burnout of internists amid COVID-19 pandemic: A cross-sectional study.

    Tanaka, Emiri / Nishimura, Yoshito / Kuriyama, Akira / Shikino, Kiyoshi / Nonaka, Saori / Ishizuka, Kosuke / Sadohara, Michito / Muramatsu, Kumiko / Makiishi, Tetsuya

    Asian journal of psychiatry

    2023  Volume 87, Page(s) 103689

    MeSH term(s) Humans ; Cross-Sectional Studies ; Pandemics ; COVID-19 ; Burnout, Professional ; Burnout, Psychological ; Health Personnel
    Language English
    Publishing date 2023-07-06
    Publishing country Netherlands
    Document type Letter
    ZDB-ID 2456678-0
    ISSN 1876-2026 ; 1876-2018
    ISSN (online) 1876-2026
    ISSN 1876-2018
    DOI 10.1016/j.ajp.2023.103689
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  7. Article ; Online: ATP13A2 modifies mitochondrial localization of overexpressed TOM20 to autolysosomal pathway.

    Hatori, Yuta / Kanda, Yukina / Nonaka, Saori / Nakanishi, Hiroshi / Kitazawa, Takeo

    PloS one

    2022  Volume 17, Issue 11, Page(s) e0276823

    Abstract: Mutations in ATP13A2 cause Kufor-Rakeb Syndrome (KRS), a juvenile form of Parkinson's Disease (PD). The gene product belongs to a diverse family of ion pumps and mediates polyamine influx from lysosomal lumen. While the biochemical and structural studies ...

    Abstract Mutations in ATP13A2 cause Kufor-Rakeb Syndrome (KRS), a juvenile form of Parkinson's Disease (PD). The gene product belongs to a diverse family of ion pumps and mediates polyamine influx from lysosomal lumen. While the biochemical and structural studies highlight its unique mechanics, how PD pathology is linked to ATP13A2 function remains unclear. Here we report that localization of overexpressed TOM20, a mitochondrial outer-membrane protein, is significantly altered upon ATP13A2 expression to partially merge with lysosome. Using Halo-fused version of ATP13A2, ATP13A2 was identified in lysosome and autophagosome. Upon ATP13A2 co-expression, overexpressed TOM20 was found not only in mitochondria but also within ATP13A2-containing autolysosome. This modification of TOM20 localization was inhibited by adding 1-methyl-4-phenylpyridinium (MPP+) and not accompanied with mitophagy induction. We suggest that ATP13A2 may participate in the control of overexpressed proteins targeted to mitochondrial outer-membrane.
    MeSH term(s) Humans ; Autophagosomes/genetics ; Autophagosomes/physiology ; Lysosomes/genetics ; Lysosomes/physiology ; Membrane Proteins ; Mitochondria/genetics ; Mitochondria/physiology ; Mitochondrial Membranes/physiology ; Mitophagy/genetics ; Mitophagy/physiology ; Proton-Translocating ATPases/genetics ; Proton-Translocating ATPases/physiology ; Parkinsonian Disorders/genetics ; Parkinsonian Disorders/physiopathology ; Mitochondrial Precursor Protein Import Complex Proteins/physiology
    Chemical Substances ATP13A2 protein, human ; Membrane Proteins ; Proton-Translocating ATPases (EC 3.6.3.14) ; TOMM20 protein, human ; Mitochondrial Precursor Protein Import Complex Proteins
    Language English
    Publishing date 2022-11-29
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2267670-3
    ISSN 1932-6203 ; 1932-6203
    ISSN (online) 1932-6203
    ISSN 1932-6203
    DOI 10.1371/journal.pone.0276823
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  8. Article ; Online: Microglial clearance of focal apoptotic synapses.

    Nonaka, Saori / Nakanishi, Hiroshi

    Neuroscience letters

    2019  Volume 707, Page(s) 134317

    Abstract: Apoptotic cells are rarely detected in vivo because of their rapid clearance by phagocytes, suggesting that apoptosis is the cell clearance rather than cell death machinery. In consistent with this, biochemical changes associated with apoptosis including ...

    Abstract Apoptotic cells are rarely detected in vivo because of their rapid clearance by phagocytes, suggesting that apoptosis is the cell clearance rather than cell death machinery. In consistent with this, biochemical changes associated with apoptosis including caspase-3 activation are engaged locally in synaptic compartments without neuronal death. This phenomenon is referred to as synaptic apoptosis or synaptosis, which triggers a rapid clearance of localized synaptic compartments by microglia. In this clearance system, integrin α
    MeSH term(s) Alzheimer Disease/metabolism ; Alzheimer Disease/pathology ; Animals ; Apoptosis ; Caspase 3/metabolism ; Complement C1q/metabolism ; Complement C3/metabolism ; Humans ; Mice ; Microglia/pathology ; Neurodegenerative Diseases/metabolism ; Neurodegenerative Diseases/pathology ; Neurons/metabolism ; Neurons/pathology ; Phosphatidylserines/metabolism ; Synapses/metabolism ; Synapses/pathology
    Chemical Substances Complement C3 ; Phosphatidylserines ; Complement C1q (80295-33-6) ; Caspase 3 (EC 3.4.22.-)
    Language English
    Publishing date 2019-06-05
    Publishing country Ireland
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Review
    ZDB-ID 194929-9
    ISSN 1872-7972 ; 0304-3940
    ISSN (online) 1872-7972
    ISSN 0304-3940
    DOI 10.1016/j.neulet.2019.134317
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  9. Article ; Online: ATP13A2 modifies mitochondrial localization of overexpressed TOM20 to autolysosomal pathway

    Yuta Hatori / Yukina Kanda / Saori Nonaka / Hiroshi Nakanishi / Takeo Kitazawa

    PLoS ONE, Vol 17, Iss

    2022  Volume 11

    Abstract: Mutations in ATP13A2 cause Kufor-Rakeb Syndrome (KRS), a juvenile form of Parkinson’s Disease (PD). The gene product belongs to a diverse family of ion pumps and mediates polyamine influx from lysosomal lumen. While the biochemical and structural studies ...

    Abstract Mutations in ATP13A2 cause Kufor-Rakeb Syndrome (KRS), a juvenile form of Parkinson’s Disease (PD). The gene product belongs to a diverse family of ion pumps and mediates polyamine influx from lysosomal lumen. While the biochemical and structural studies highlight its unique mechanics, how PD pathology is linked to ATP13A2 function remains unclear. Here we report that localization of overexpressed TOM20, a mitochondrial outer-membrane protein, is significantly altered upon ATP13A2 expression to partially merge with lysosome. Using Halo-fused version of ATP13A2, ATP13A2 was identified in lysosome and autophagosome. Upon ATP13A2 co-expression, overexpressed TOM20 was found not only in mitochondria but also within ATP13A2-containing autolysosome. This modification of TOM20 localization was inhibited by adding 1-methyl-4-phenylpyridinium (MPP+) and not accompanied with mitophagy induction. We suggest that ATP13A2 may participate in the control of overexpressed proteins targeted to mitochondrial outer-membrane.
    Keywords Medicine ; R ; Science ; Q
    Subject code 570
    Language English
    Publishing date 2022-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  10. Article ; Online: Human β-Defensin 3 Inhibits Porphyromonas Gingivalis Lipopolysaccharide-Induced Oxidative and Inflammatory Responses of Microglia by Suppression of Cathepsins B and L

    Erika Inoue / Shiyo Minatozaki / Yui Katsuta / Saori Nonaka / Hiroshi Nakanishi

    International Journal of Molecular Sciences, Vol 23, Iss 15099, p

    2022  Volume 15099

    Abstract: Recently, the effects of antibacterial peptides are suggested to have therapeutic potential in Alzheimer’s disease. Furthermore, systemic treatment of Porphyromonas gingivalis ( Pg ) lipopolysaccharide (LPS) induced Alzheimer’s disease-like ... ...

    Abstract Recently, the effects of antibacterial peptides are suggested to have therapeutic potential in Alzheimer’s disease. Furthermore, systemic treatment of Porphyromonas gingivalis ( Pg ) lipopolysaccharide (LPS) induced Alzheimer’s disease-like neuropathological changes in middle-aged mice. Then, we examined whether human β-defensins (hBDs), antimicrobial peptides produced by the oral mucosa and salivary glands, can suppress Pg LPS-induced oxidative and inflammatory responses by microglia. hBD3 (1 μM) significantly suppressed Pg LPS-induced production of nitric oxide and interleukin-6 (IL-6) by MG6 cells, a mouse microglial cell line. hBD3 (1 μM) also significantly inhibited Pg LPS-induced expression of IL-6 by HMC3 cells, a human microglial cell line. In contrast, neither hBD1, hBD2 nor hBD4 failed to inhibit their productions. Furthermore, hBD3 suppressed Pg LPS-induced p65 nuclear translocation through the IκBα degradation. Pg LPS-induced expression of IL-6 was significantly suppressed by E64d, a cysteine protease inhibitor, and CA-074Me, a known specific inhibitor for cathepsin B, but not by pepstatin A, an aspartic protease inhibitor. Interestingly, hBD3 significantly inhibited enzymatic activities of recombinant human cathepsins B and L, lysosomal cysteine proteases, and their intracellular activities in MG6 cells. Therefore, hBD3 suppressed oxidative and inflammatory responses of microglia through the inhibition of cathepsins B and L, which enzymatic activities are necessary for the NF-κB activation.
    Keywords antibacterial peptide ; cathepsin B ; cathepsin L ; human β-defensins ; interleukin-6 ; lipopolysaccharide ; Biology (General) ; QH301-705.5 ; Chemistry ; QD1-999
    Language English
    Publishing date 2022-12-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

To top