90 results on '"Segawa, R"'
Search Results
2. Phylogeny of Hydrothermal-Vent-Endemic Gastropods Alviniconcha spp. from the Western Pacific Revealed by Mitochondrial DNA Sequences
- Author
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Kojima, S., Segawa, R., Fijiwara, Y., Fujikura, K., Ohta, S., and Hashimoto, J.
- Published
- 2001
- Full Text
- View/download PDF
3. Expression of Protein Gene Product 9.5 and Sal-like Protein 4 in Canine Seminomas
- Author
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Hara, S., Morita, R., Shiraki, A., Segawa, R., Ogawa, T., Takimoto, N., Suzuki, K., Nomura, K., and Shibutani, M.
- Published
- 2014
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4. Dissipation and Offsite Movement of Forestry Herbicides in Plants of Importance to Native Americans in California National Forests
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Ando, C., Segawa, R., Gana, C., Li, L., Walters, J., Sava, R., Barry, T., Goh, K. S., Lee, P., Tran, D., White, J., and Hsu, J.
- Published
- 2003
- Full Text
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5. Setting Fumigant Application Buffer Zones
- Author
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Barry, T. A., primary, Johnson, B., additional, and Segawa, R., additional
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- 2007
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6. Residues of Forestry Herbicides in Plants of Importance to California Native Americans
- Author
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Segawa, R., Bradley, A., Lee, P., Tran, D., Hsu, J., White, J., and Goh, K. S.
- Published
- 1997
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7. Molecular phylogeny of vestimentiferans collected around Japan, revealed by the nucleotide sequences of mitochondrial DNA
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Kojima, S., Segawa, R., Hashimoto, J., and Ohta, S.
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- 1997
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8. Phylogenetic relationships among species of Calyptogena (Bivalvia: Vesicomyidae) collected around Japan revealed by nucleotide sequences of mitochondrial genes
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Kojima, S., Segawa, R., Kobayashi, T., Hashimoto, T., Fujikura, K., Hashimoto, J., and Ohta, S.
- Published
- 1995
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9. Off-Site Air Monitoring Following Methyl Bromide Chamber and Warehouse Fumigations and Evaluation of the Industrial Source Complex—Short Term 3 Air Dispersion Model
- Author
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Barry, T. A., primary, Segawa, R., additional, Wofford, P., additional, and Ganapathy, C., additional
- Published
- 1996
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10. A Non-joint Tissue Biphasic Synovial Sarcoma in a Dog
- Author
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Takimoto, N., Suzuki, K., Ogawa, T., Segawa, R., Hara, S., Itahashi, M., Kimura, M., Iwasaki, N., Nishifuji, K., and Shibutani, M.
- Published
- 2014
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11. Phylogeography of a deep-sea demersal fish, Bothrocara hollandi, in the Japan Sea
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Kojima, S, primary, Segawa, R, additional, Hayashi, I, additional, and Okiyama, M, additional
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- 2001
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12. Genetic differentiation among populations of the Japanese turban shell Turbo (Batillus) cornutus corresponding to warm currents
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Kojima, S, primary, Segawa, R, additional, and Hayashi, I, additional
- Published
- 1997
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13. An 80-MFLOPS (peak) 64-b microprocessor for parallel computer
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Nakano, H., primary, Nakajima, M., additional, Nakakura, Y., additional, Yoshida, T., additional, Goi, Y., additional, Nakai, Y., additional, Segawa, R., additional, Kishida, T., additional, and Kadota, H., additional
- Published
- 1992
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14. Design methodology for over 100MFLOPS 64bit MPU with 0.8/spl mu/m BiCMOS technology
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Nakakura, Y., primary, Yoshida, T., additional, Nakano, H., additional, Nakajima, M., additional, Goi, Y., additional, Nakai, Y., additional, Segawa, R., additional, Kishida, T., additional, Kameyama, S., additional, and Kadota, H., additional
- Published
- 1991
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15. Visualization of tumor necrosis factor-α distributions within pressure ulcer tissue using the wound blotting method: A case report and discussion
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Kitamura, A., Gojiro Nakagami, Yoshida, M., Noguchi, H., Nishijima, Y., Minematsu, T., Naito, A., Sugawara, J., Shibayama, H., Takahashi, K., Hakuta, A., Umemoto, J., Terada, N., Segawa, R., Mori, T., and Sanada, H.
16. A 80 MFLOPS 64-bit microprocessor for parallel computer.
- Author
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Nakano, H., Nakajima, M., Nakakura, Y., Yoshida, T., Goi, Y., Nakai, Y., Segawa, R., Kishida, T., and Kadota, H.
- Published
- 1991
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17. Phylogenetic relationships among species of Calyptogena (Bivalvia: Vesicomyidae) collected around Japan revealed by nucleotide sequences of mitochondrial genes
- Author
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Segawa, R., Hashimoto, T., Kobayashi, T., Kojima, S., Ohta, S., Fujikura, K., and Hashimoto, J.
- Subjects
GENES ,NUCLEOTIDE sequence ,PHYLOGENY - Published
- 1995
18. Oxoammonium salts exert antiviral effects against coronavirus via denaturation of their spike proteins.
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Segawa R, Sasano Y, Hatakawa Y, Fujisawa Y, Akutsu S, Uchimura M, Ikura A, Matsumoto K, Sone K, Oe T, Iwabuchi Y, Ito M, and Hirasawa N
- Subjects
- Humans, Cyclic N-Oxides chemistry, Cyclic N-Oxides pharmacology, Animals, Nitrogen Oxides chemistry, Nitrogen Oxides pharmacology, Angiotensin-Converting Enzyme 2 metabolism, Angiotensin-Converting Enzyme 2 chemistry, COVID-19 Drug Treatment, Adamantane pharmacology, Adamantane chemistry, Adamantane analogs & derivatives, Antiviral Agents pharmacology, Antiviral Agents chemistry, Spike Glycoprotein, Coronavirus metabolism, Spike Glycoprotein, Coronavirus chemistry, SARS-CoV-2 drug effects
- Abstract
Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV2) infection has forced social changes worldwide. Development of potent antiviral agents is necessary to prevent future pandemics. Titanium oxide, a photocatalyst, is a long-acting antiviral agent; however, its effects are weakened in the dark. Therefore, new antiviral substances that can be used in the dark are needed. Two types of nitroxyl radicals, 2,2,6,6-tetramethylpiperidine N-oxyl (TEMPO) and 2-azaadamantane N-oxyl (AZADO), are commonly used as oxidation catalysts utilizing oxygen in the air as the terminal oxidant. Therefore, in this study, we aimed to evaluate the potential of these radicals as antiviral compounds with sustained activity even in the dark. We evaluated the antiviral effects of oxoammonium salts corresponding to TEMPO and AZADO (TEMPO-Oxo and AZADO-Oxo, respectively), which are the active forms of nitroxyl radicals in oxidation reactions. TEMPO-Oxo and AZADO-Oxo inhibited the binding of SARS-CoV2 spike protein receptor-binding domain (S-RBD) to angiotensin-converting enzyme 2. Notably, AZADO-Oxo exhibited a 10-fold stronger inhibitory effect than TEMPO-Oxo. TEMPO-Oxo and AZADO-Oxo also denatured S-RBD; however, effects of AZADO-Oxo were 10-fold stronger than those of TEMPO-Oxo and did not change in the dark. Some S-RBD peptides treated with AZADO-Oxo were cleaved at the N-terminal side of tyrosine residues. TEMPO-Oxo and AZADO-Oxo exhibited concentration-dependent antiviral effects against feline coronavirus. In conclusion, active forms of the nitroxyl radicals, TEMPO-Oxo and AZADO-Oxo, exerted antiviral effects by denaturing S-RBD, regardless of the presence or absence of light, suggesting their potential as novel antiviral agents., (© 2024. The Author(s).)
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- 2024
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19. Feasibility of a problem-solving exercise program based on short physical performance battery for older patients with chronic respiratory diseases: A multicenter, pilot clinical trial.
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Hanada M, Nonoyama T, Ikeuchi T, Sasaki K, Suyama K, Nakashita M, Shiroishi R, Segawa R, Tanaka K, Aoki H, Kitagawa C, Hori Y, Hashimoto S, Matsuzaki T, Sato S, Arizono S, Tanaka T, and Kozu R
- Abstract
Background: This study aimed to assess the feasibility and safety of a problem-solving exercise program based on the items in the short physical performance battery (SPPB) for older patients with chronic respiratory diseases (CRDs) to inform future randomized controlled trials., Methods: This was a multicenter, prospective, non-randomized feasibility study. Participants with CRD received an enhancement program based on the SPPB decline items (balance, walk, and/or chair stand) for 4 weeks. The feasibility, safety, and efficacy of the problem-solving exercise program in improving the SPPB score, physical function, and step count (measured using a pedometer) were assessed., Results: Overall, 36 patients were enrolled in this study, and adherence to the exercise program was high (100%). No exercise program-related adverse events were observed. The implementation of the exercise program ranged from 70 to 100%. The mean daily step count increased from 2152 ± 1498 steps during the first week to 2899 ± 1865 steps in the last week (p<0.01). Additionally, the SPPB total score increased from 8.9 ± 1.8 points to 10.7 ± 1.3 points at the end of the program (p<0.001)., Conclusions: The problem-solving exercise program based on SPPB is feasible and safe for older patients with CRDs. However, the effectiveness of this exercise program should be validated in large-scale, randomized-controlled trials in the future., Trial Registration: University Hospital Medical Information Network Center (UMIN-CTR) UMIN: approval number: UMIN000048761., Competing Interests: Declaration of competing interest The authors have no conflicts of interest., (Copyright © 2024. Published by Elsevier B.V.)
- Published
- 2024
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20. Identification of amino acids in transmembrane domains of mutated cytokine receptor-like factor 2 and interleukin-7 receptor α required for constitutive signal transduction.
- Author
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Yamamoto R, Segawa R, Kato H, Niino Y, Sato T, Hiratsuka M, and Hirasawa N
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- Humans, Amino Acid Substitution, Amino Acids genetics, Amino Acids metabolism, HEK293 Cells, Interleukin-7 Receptor alpha Subunit metabolism, Interleukin-7 Receptor alpha Subunit genetics, Mutation genetics, Phosphorylation, Protein Domains genetics, Protein Multimerization genetics, Receptors, Interleukin-7, STAT5 Transcription Factor metabolism, STAT5 Transcription Factor genetics, Receptors, Cytokine genetics, Receptors, Cytokine metabolism, Receptors, Cytokine chemistry, Signal Transduction genetics
- Abstract
Cytokine receptor-like factor 2 (CRLF2) and interleukin-7 receptor α (IL-7Rα) form a receptor for thymic stromal lymphopoietin (TSLP). A somatic mutation consisting of the substitution of five amino acids (SLLLL) in the transmembrane domain of CRLF2 with three amino acids, including glutamic acid, isoleucine, and methionine (insEIM), which has been identified in acute lymphocytic leukemia, causes the TSLP-independent dimerization with IL-7Rα and activation. However, the dimerization mechanism remains unclear. In this study, we examined the involvement of the amino acids in the transmembrane domains of EIM CRLF2 and IL-7Rα in TSLP-independent activation. HEK293 cells were transfected with vectors encoding CRLF2 and IL-7Rα, or their mutants, in which the amino acid of the transmembrane domain was replaced with alanine. STAT5 phosphorylation was detected using western blotting, and receptor dimerization was analyzed using the NanoBiT assay. The substitution of glutamic acid within the insEIM mutation for alanine failed to cause the STAT5 phosphorylation in the absence of TSLP. Moreover, the alanine substation of the specific leucine residues in the transmembrane domains of both CRLF2 and IL-7Rα abrogated the TSLP-independent signal transduction and dimerization. The mutation of IL-7Rα W264 partially reduced the phosphorylation of STAT5 without affecting receptor dimerization. These results suggest that the amino acids in the transmembrane domains of EIM CRLF2 and IL-7Rα play at least three possible functions: interaction through hydrogen bonds, hydrophobic interaction, and signal transduction. Our findings contribute to a better understanding of the function of the transmembrane domains of cytokine receptors in their dimerization and signal transduction., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2024
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21. Biological Evaluation of Isosteric Applicability of 1,3-Substituted Cuneanes as m-Substituted Benzenes Enabled by Selective Isomerization of 1,4-Substituted Cubanes.
- Author
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Fujiwara K, Nagasawa S, Maeyama R, Segawa R, Hirasawa N, Hirokawa T, and Iwabuchi Y
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- Isomerism, Benzene chemistry, Benzene Derivatives chemistry
- Abstract
We herein evaluate a biological applicability of 1,3-substituted cuneanes as an isostere of m-substituted benzenes based on its structural similarity. An investigation of a method to obtain 1,3-substituted cuneanes by selective isomerization of 1,4-substituted cubanes enables this attempt by giving a key synthetic step to obtain a cuneane analogs of pharmaceuticals having m-substituted benzene moiety. Biological evaluation of the synthesized analogs and in silico study of the obtained result revealed a potential usage of cuneane skeleton in medicinal chemistry., (© 2023 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)
- Published
- 2024
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22. Caspases downregulate nickel and hydrogen peroxide-induced IL-8 production via modification of c-Jun N-terminal kinases.
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Maeyama R, Segawa R, Onodera R, Hiratsuka M, and Hirasawa N
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- Hydrogen Peroxide toxicity, Nickel toxicity, Interleukin-8, Apoptosis, Tumor Necrosis Factor-alpha, Caspases metabolism, JNK Mitogen-Activated Protein Kinases
- Abstract
Nickel (Ni) is a typical hapten in allergic contact dermatitis. However, it has been used in various metal materials due to its usefulness. Although Ni ions induce apoptosis of inflammatory cells and the expression of inflammatory cytokines such as interleukin-8 (IL-8), the effects of the apoptotic pathway on the signaling that induces cytokine production have not been sufficiently clarified. Here, we found that NiCl
2 -induced IL-8 production was enhanced by the pan-caspase inhibitor Z-VAD-FMK in THP-1 cells. Moreover, Z-VAD-FMK enhanced H2 O2 -induced and NiCl2 -induced IL-8 production, but not TNF-α-induced one. The analyses of signaling pathways apparently showed that NiCl2 - and H2 O2 -induced phosphorylation of c-Jun, but not TNF-α-induced one were enhanced by Z-VAD-FMK. The cleavages of p54c-Jun N-terminal kinase (JNK) as well as PARP was induced by NiCl2 and H2 O2 but not by TNF-α. Finally, a JNK inhibitor, SP600125, inhibited Z-VAD-FMK-induced enhancement of IL-8 production. In summary, we showed that caspase activation in the apoptotic pathway actively downregulates the JNK-mediated activation of inflammatory cells. This study highlighted the significance of apoptosis in inflammatory diseases, including Ni-induced dermatitis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)- Published
- 2024
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23. Effect of N-glycosylation on constitutive signal transduction by mutated cytokine receptor-like factor 2.
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Yamamoto R, Segawa R, Liu J, Isaji T, Gu J, Hiratsuka M, and Hirasawa N
- Abstract
Background: Cytokine receptor-like factor 2 (CRLF2) is a subunit of the receptor for thymic stromal lymphopoietin (TSLP). A somatic mutation (insEIM) in the transmembrane domains of CRLF2 has been identified in acute lymphocytic leukemia (ALL), and Glu-Ile-Met (EIM) CRLF2 induces constitutive activation of signals. However, the signaling mechanism remains unclear., Methods: HEK293 cells were transfected with expression vectors encoding wild-type (WT), insEIM CRLF2, or their mutants which N-glycosylation site was replaced with a glutamine. Cell surface expression of CRLF2 was assessed by flow cytometry. Total CRLF2 and phosphorylated signal transducer and activator of transcription 5 (STAT5) were detected by western blotting., Results: Three major species of CRLF2 (53-, 57- and 58-kDa) were identified. Deglycosylation analysis revealed that they were modified with complex-type and oligomannose-type glycans. The expression of both WT and EIM CRLF2 decreased in N-acetylglucosaminyltransferase (GnT)-I (MGAT1) knockout (KO) cells and slightly decreased in α1,6-fucosyltransferase (Fut8) KO cells compared to that in the control cells. In GnT-I or Fut8 KO cells, WT CRLF2 did not induce ligand-independent activation. Both WT and EIM CRLF2 contained four N-glycosylation sites. N55 of CRLF2 was required for the cell surface expression and activation by EIM CRLF2., Conclusions: We found that N-glycosylation of CRLF2 plays crucial roles for its cell surface expression and signaling. However, N-glycan processing in the Golgi apparatus does not seem to be essential for ligand-independent activation of EIM CRLF2., General Significance: Our studies provide a crucial role of glycosylation in the cell surface expression of receptors., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing interests., (Copyright © 2023 Elsevier B.V. All rights reserved.)
- Published
- 2023
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24. Hypoxia-inducible factor prolyl hydroxylase inhibitors suppressed thymic stromal lymphopoietin production and allergic responses in a mouse air-pouch-type ovalbumin sensitization model.
- Author
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Segawa R, Kyoda T, Yagisawa M, Muramatsu T, Hiratsuka M, and Hirasawa N
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- Animals, Humans, Mice, Cytokines metabolism, Hypoxia, Ovalbumin therapeutic use, Prolyl Hydroxylases metabolism, Thymic Stromal Lymphopoietin metabolism, Dermatitis, Atopic drug therapy, Prolyl-Hydroxylase Inhibitors pharmacology, Prolyl-Hydroxylase Inhibitors therapeutic use
- Abstract
Atopic dermatitis (AD) is an allergic skin disease, triggered by excessive type 2 immune reactions. Thymic stromal lymphopoietin (TSLP) is an epithelial-derived cytokine that induces type 2 immune response through dendritic cell activation. Therefore, TSLP inhibitors may serve as novel antiallergic drugs. Hypoxia-inducible factor (HIF) activation in the epithelia contributes to several homeostatic phenomena, such as re-epithelialization. However, the effects of HIF activation on TSLP production and immune activation in the skin remain unclear. In this study, we found that selective HIF prolyl hydroxylase inhibitors (PHD inhibitors), which induce HIF activation, suppressed TSLP production in a mouse ovalbumin (OVA) sensitization model. PHD inhibitors also suppressed the production of tumor necrosis factor-alpha (TNF-α), which is a major inducer of TSLP production, in this mouse model and in a macrophage cell line. Consistent with these findings, PHD inhibitors suppressed OVA-specific IgE levels in the serum and OVA-induced allergic responses. Furthermore, we found a direct suppressive effect on TSLP expression in a human keratinocyte cell line mediated by HIF activation. Taken together, our findings suggest that PHD inhibitors exert antiallergic effects by suppressing TSLP production. Controlling the HIF activation system has therapeutic potential in AD., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)
- Published
- 2023
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25. Frustoconical porous microneedle for electroosmotic transdermal drug delivery.
- Author
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Terutsuki D, Segawa R, Kusama S, Abe H, and Nishizawa M
- Subjects
- Animals, Swine, Porosity, Drug Delivery Systems, Microinjections, Administration, Cutaneous, Skin, Needles, Electroosmosis, Pathogen-Associated Molecular Pattern Molecules
- Abstract
A truncated cone-shaped porous microneedle (PMN) made of poly-glycidyl methacrylate was studied as a minimally invasive tool for transdermal drug delivery. The transdermal electrical resistance of a pig skin was evaluated during the indentation of the PMNs, revealing that the frustoconical PMN (300 μm height) significantly reduced the resistance of the skin by expanding the stratum corneum without penetrating into the skin. A thin film of poly (2-acrylamido-2-methylpropanesulfonic acid) (PAMPS) was grafted onto the inner wall of the microchannels of the frustoconical PMN to generate electroosmotic flow (EOF) upon current application in the direction of injection of the drug into the skin. Owing to the synergy of the expansion of the stratum corneum and the EOF-promotion, the PAMPS-modified frustoconical PMN effectively enhances the penetration of larger (over 500 Da) molecules, such as dextran (∼10 kDa)., Competing Interests: Declaration of Competing Interest No conflict of interest was reported by the authors., (Copyright © 2023 Elsevier B.V. All rights reserved.)
- Published
- 2023
- Full Text
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26. Selective induction of thymic stromal lymphopoietin expression by novel nitrogen-containing steroid compounds in PAM-212 cells.
- Author
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Wang Y, Segawa R, Weng Y, Nakai K, Ohashi K, Hiratsuka M, Arisawa M, and Hirasawa N
- Abstract
Background: Thymic stromal lymphopoietin (TSLP) has been shown to be able to amplify Tregs. Thus, TSLP induction has the potential to induce endogenous Tregs and control autoimmunity. In the previous research, we found that a new compound named 02F04 can induce TSLP production while simultaneously activating the liver X receptor (LXR). Because LXR activation leads to a decrease in Treg, we attempted to find a 02F04-derivative, druggable lead compound with a basic skeleton that induces TSLP production without activating LXR. As the results, we found HA-7 and HA-19 and, in this study, examined the molecular mechanisms in TSLP production., Methods: A murine keratinocyte cell line PAM 212 was stimulated with HA-7 and HA-19, and then the expressions of cytokines were examined via ELISA and real-time fluorescence quantitative PCR., Results: HA-7 and HA-19 induced TSLP production but almost not the expression of TNF-α, IL-13, IL-25, and IL-33 in PAM212 cells. These compounds inhibited LXR activities. The TSLP expression induced by HA-7 and HA-19 was inhibited by the Gq/11 inhibitor YM-254890, ROCK inhibitor Y-27632, and ERK inhibitor U0126. HA-7 and HA-19 also induced the formation of stress fiber and ERK phosphorylation, which were inhibited by YM-254890 and Y-27632., Conclusions: Our findings indicated that HA-7 and HA-19 selectively induced TSLP production in PAM212 via Gq/11, Rho/ROCK and ERK pathways. Our findings also indicated that TSLP expression was differentially regulated from other cytokines, and the selective expression could be induced with low-molecular-weight compounds such as HA-7 and HA-19., (© 2023 The Authors.)
- Published
- 2022
- Full Text
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27. Inhibition of thymic stromal lymphopoietin production by FK3453.
- Author
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Segawa R, Ishihara R, Hiratsuka M, and Hirasawa N
- Subjects
- Animals, Cytokines metabolism, Keratinocytes metabolism, Mice, Pyridazines, Pyrimidines, Thymic Stromal Lymphopoietin, Hypersensitivity, Tumor Necrosis Factor-alpha metabolism
- Abstract
To prevent the onset and aggravation of allergic diseases, it is necessary to modulate excessive Th2-type immune responses. It is well accepted that thymic stromal lymphopoietin (TSLP) plays important roles in the change of Th1/Th2 balance to Th2 dominance and would be a druggable target. In this study, using a drug repositioning strategy, we identified 6-(2-amino-4-phenylpyrimidine-5-yl)-2-isopropylpyridazin-3(2H)-one (FK3453) as a novel inhibitor of TSLP production. FK3453 inhibited constitutive production of TSLP in the KCMH-1 mouse keratinocyte cell line and 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced one in PAM212 cells. FK3453 also inhibited TSLP mRNA expression induced by a mixture of tumor necrosis factor alpha (TNF-α), interleukin (IL)-4, fibroblast-stimulation lipopeptide-1, and protease activated-receptor agonist and TPA in normal human epidermal keratinocytes (NHEKs). Although FK3453 inhibited TPA-induced IL-33 expression in NHEKs in addition to TSLP, it did not inhibit TNF-α and IL-6 production. In addition, FK3453 did not inhibit MAP kinase (ERK) phosphorylation. We have confirmed that topical treatment with FK3453 inhibited TSLP production in the lipopolysaccharide-induced air pouch-type inflammation model. FK3453 could be a lead compound for a novel type of medicine which prevents the onset and aggravation of allergic diseases., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2022 The Authors. Production and hosting by Elsevier B.V. All rights reserved.)
- Published
- 2022
- Full Text
- View/download PDF
28. [Rupture of hepatic lesion of diffuse large B-cell lymphoma following immunochemotherapy].
- Author
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Segawa R and Natazuka T
- Subjects
- Antineoplastic Combined Chemotherapy Protocols therapeutic use, Cyclophosphamide therapeutic use, Doxorubicin therapeutic use, Female, Humans, Middle Aged, Prednisone therapeutic use, Rituximab therapeutic use, Vincristine therapeutic use, Liver Neoplasms complications, Liver Neoplasms drug therapy, Lymphoma, Large B-Cell, Diffuse diagnosis, Lymphoma, Large B-Cell, Diffuse drug therapy
- Abstract
A 51-year-old woman presented to the outpatient clinic with appetite loss and abdominal pain that had persisted for 1 month. Computed tomography (CT) showed a bulky tumor in the right liver, with hepatosplenomegaly and lymphadenopathy in several para-aortic lymph nodes. The diagnosis of diffuse large B-cell lymphoma was confirmed by a biopsy of a submucosal tumor in the stomach. Bone marrow invasion by lymphoma cells was observed. On day5 after a rituximab, cyclophosphamide, vincristine, and prednisone (R-CVP) regimen was initiated, epigastralgia and right hypochondralgia were noted. On day6, severe anemia (hemoglobin level, 4.2 g/dl) developed. Repeat CT showed a low-density area surrounding the hepatic tumor caused by tumor lysis, and hepatic tumor rupture was suspected. Transfusion was performed, and no signs of recurrence of bleeding were noted after the procedure. On day21, angiography of the hepatic artery showed no signs of bleeding. After two cycles of R-CVP therapy and eight cycles of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone therapy, partial remission was achieved. In this report, we present a rare case of patient survival following hepatic tumor rupture associated with hepatic lymphoma after treatment.
- Published
- 2022
- Full Text
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29. A chalcone derivative suppresses TSLP induction in mice and human keratinocytes through binding to BET family proteins.
- Author
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Segawa R, Takeda H, Yokoyama T, Ishida M, Miyata C, Saito T, Ishihara R, Nakagita T, Sasano Y, Kanoh N, Iwabuchi Y, Mizuguchi M, Hiratsuka M, and Hirasawa N
- Subjects
- Animals, Cell Line, Chalcones chemistry, Crystallography, X-Ray, Cytokines biosynthesis, Dose-Response Relationship, Drug, Humans, Mice, Mice, Inbred BALB C, Protein Binding physiology, Protein Structure, Secondary, Thymic Stromal Lymphopoietin, Chalcones metabolism, Chalcones pharmacology, Cytokines antagonists & inhibitors, Keratinocytes drug effects, Keratinocytes metabolism, Nerve Tissue Proteins metabolism, Receptors, Cell Surface metabolism
- Abstract
Although treatments for allergic diseases have improved, side effects and treatment resistance remain as challenges. New therapeutic drugs for allergic diseases are urgently required. Thymic stromal lymphopoietin (TSLP) is a cytokine target for prevention and treatment of allergic diseases. Since TSLP is produced from epithelial cells in allergic diseases, TSLP inhibitors may be new anti-allergic drugs. We previously identified a new inhibitor of TSLP production, named 16D10. However, its target of action remained unclarified. In this study, we found proteins binding to 16D10 from 24,000 human protein arrays by AlphaScreen-based high-throughput screening and identified bromodomain and extra-terminal (BET) family proteins as targets. We also clarified the detailed mode of interaction between 16D10 and a BET family protein using X-ray crystallography. Furthermore, we confirmed that inhibitors of BET family proteins suppressed TSLP induction and IL-33 and IL-36γ expression in both mouse and human keratinocyte cell lines. Taken together, our findings suggest that BET family proteins are involved in the suppression of TSLP production by 16D10. These proteins can contribute to the pathology of atopic dermatitis via TSLP regulation in keratinocytes and have potential as therapeutic targets in allergic diseases., (Copyright © 2021 Elsevier Inc. All rights reserved.)
- Published
- 2021
- Full Text
- View/download PDF
30. Lactate released from human fibroblasts enhances Ni elution from Ni plate.
- Author
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Kasai K, Segawa R, Onodera R, Asakawa S, Hiratsuka M, and Hirasawa N
- Subjects
- Cell Line, Fibroblasts drug effects, Humans, Nickel pharmacology, Fibroblasts metabolism, Lactic Acid metabolism, Nickel metabolism
- Abstract
Elution of Ni ions from medical devices induces inflammation and toxicity. We previously reported that elution of Ni ions from Ni wires induced COX-2 expression and increased lactate production, but whether lactate is involved in the further elution of Ni ions remains unclear. In this study, using KMST-6, a human fibroblast cell line, we examined the molecular mechanisms by which Ni ions increase lactate release and the role of lactate in enhancing the elution of Ni ions. When KMST-6 cells were incubated on a Ni plate or stimulated with NiCl
2 (1 mM), the expression of glucose transporter 1 (GLUT1), hexokinase 2 (HK2), and lactate dehydrogenase A (LDHA), and the release of lactate were enhanced. The NiCl2 (1 mM)-induced expression of these genes was inhibited by a hypoxia-inducible factor-1α (HIF-1α) inhibitor, PX-478 (10-25 μM). Stimulation of cells with a prolyl hydroxylase domain (PHD) inhibitor, roxadustat, increased the expression of these genes, lactate release, and elution of Ni ions at 10 μM. A monocarboxylate transporter-4 (MCT4) inhibitor, syrosingopine, inhibited lactate release from roxadustat-treated cells and reduced the elution of Ni ions by the cells at 10 μM. Finally, syrosingopine (10 μM) reduced the elution of Ni ions by the cells from the Ni plate. These results suggest that elution of Ni ions from metals promotes the production of lactate via HIF-1α-mediated gene expression and causes further Ni elution. Thus, Ni ions show a positive feedback mechanism of Ni elution, and this step may be potentially targeted to protect against metal elution from metal devices., (Copyright © 2021 Elsevier B.V. All rights reserved.)- Published
- 2021
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31. [Search for Compounds Regulating TSLP Production].
- Author
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Segawa R
- Subjects
- Animals, Cells, Cultured, Drug Development, Epithelial Cells metabolism, Humans, Hypersensitivity drug therapy, Mice, Molecular Targeted Therapy, Thymic Stromal Lymphopoietin, Anti-Allergic Agents pharmacology, Chalcones pharmacology, Cytokines biosynthesis, ErbB Receptors pharmacology, Hypersensitivity immunology
- Abstract
Thymic stromal lymphopoietin (TSLP) is an epithelial cell-derived immunostimulatory factor, which activates several immune cells such as dendritic cells, T cells, and mast cells. Recently, epithelial cell-derived TSLP has gained immense attention as a cytokine that induces allergic immune responses. Therefore, understanding the regulation of TSLP production is an important step in uncovering the pathophysiology of allergic diseases. Moreover, the compounds that regulate TSLP production can be used as therapeutic drugs for the treatment of allergic diseases. We aim to elucidate the detailed regulation of TSLP production from epithelial cells, and in doing so discovered new regulating factors and an inhibitor of TSLP production. This review article explains the role of TSLP in allergic diseases, its regulation, and our research results.
- Published
- 2021
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32. Hypoxia inhibits TNF-α-induced TSLP expression in keratinocytes.
- Author
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Tashiro N, Segawa R, Tobita R, Asakawa S, Mizuno N, Hiratsuka M, and Hirasawa N
- Subjects
- Amino Acids, Dicarboxylic pharmacology, Animals, Basic Helix-Loop-Helix Transcription Factors antagonists & inhibitors, Basic Helix-Loop-Helix Transcription Factors metabolism, Cell Hypoxia physiology, Cell Line, Cytokines immunology, Dermatitis, Atopic drug therapy, Dermatitis, Atopic immunology, Gene Expression Regulation physiology, Humans, Hypoxia-Inducible Factor 1, alpha Subunit antagonists & inhibitors, Hypoxia-Inducible Factor 1, alpha Subunit metabolism, Mice, Mustard Compounds pharmacology, Phenylpropionates pharmacology, Prolyl Hydroxylases metabolism, Prolyl-Hydroxylase Inhibitors pharmacology, Prolyl-Hydroxylase Inhibitors therapeutic use, Promoter Regions, Genetic genetics, Psoriasis drug therapy, Psoriasis immunology, Signal Transduction drug effects, Signal Transduction physiology, Thymic Stromal Lymphopoietin, Cytokines metabolism, Keratinocytes metabolism, Tumor Necrosis Factor-alpha metabolism
- Abstract
The expression of thymic stromal lymphopoietin (TSLP), a cytokine which greatly contributes to the induction of type I allergy, is upregulated in chronic inflammation such as atopic dermatitis and psoriasis. As hypoxia in the epidermis is important for maintaining skin homeostasis, we examined the regulation of TSLP expression by hypoxic conditions in normal skin epithelial tissues. TNF-α-induced expression of TSLP in human keratinocyte HaCaT and in mouse keratinocyte PAM212 cell lines were inhibited under hypoxic condition (1% O2), although the mRNA expressions of TNF-α, IL-6, IL-8, MCP-1, and VEGF-A were not inhibited. Hypoxia-mimicking conditions, which include NiCl2, CoCl2, and DMOG, an inhibitor of 2-oxoglutarate-dependent enzymes, also selectively inhibited TNF-α-induced TSLP expression. These results suggested that inactivation of prolyl hydroxylase by hypoxia and hypoxia-mimicking conditions is involved in the repression of TNF-α-induced TSLP expression. Interestingly, the inhibition of TSLP production by hypoxic treatment was significantly reversed by treatment with the HIF-2α antagonist but not with the HIF-1α inhibitor. DMOG-induced inhibition of TSLP promoter activity was dependent on the -71 to +185 bp promoter region, suggesting that the binding of HIF-2 to hypoxia response element (HRE) in this region repressed the TSLP expression. These results indicated that hypoxia and hypoxia-mimicking conditions inhibited TSLP expression via HIF-2 and HRE-dependent mechanisms. Therefore, PHD and HIF-2α could be a new strategy for treatment of atopic dermatitis and psoriasis., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2019
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33. A chalcone derivative suppresses the induction of TSLP in mice and human keratinocytes and attenuates OVA-induced antibody production in mice.
- Author
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Segawa R, Shiraki M, Sudo S, Shigeeda K, Saito T, Mizuno N, Moriya T, Yonezawa T, Woo JT, Hiratsuka M, and Hirasawa N
- Subjects
- Animals, Cell Line, Drug Evaluation, Preclinical, Humans, Keratinocytes immunology, Male, Mice, NF-kappa B metabolism, Thymic Stromal Lymphopoietin, Antibody Formation drug effects, Chalcones chemistry, Chalcones pharmacology, Cytokines metabolism, Keratinocytes drug effects, Keratinocytes metabolism, Ovalbumin pharmacology
- Abstract
Thymic stromal lymphopoietin (TSLP) is a key epithelial-derived factor that aggravates allergic diseases. Therefore, TSLP inhibitors are candidate compounds for the treatment of allergic diseases. Previously, we reported that KCMH-1, a mouse keratinocyte cell line, constitutively produces TSLP. In this study, we tried to identify inhibitors of TSLP by screening 2169 compounds in KCMH-1 cells and found one such chalcone derivative (code no. 16D10). 16D10 inhibited TSLP expression and TSLP promoter activation in HaCaT cells, a human keratinocyte cell line. Although nuclear factor kappa-B (NF-κB) is a key transcription factor for the induction of TSLP, 16D10 did not inhibit the activation pathway of NF-κB, such as degradation of inhibitor of κB (IκB) and p65 nuclear translocation. 16D10 activated the Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor (erythroid-derived 2)-like 2 (Nrf2) system, although this system was not involved in the inhibitory effect of 16D10. 16D10 also inhibited TSLP production in a lipopolysaccharide (LPS)- or ovalbumin (OVA)-induced air-pouch-type inflammation model. Further, repeated 16D10 administration diminished serum immunoglobulin G1 (IgG1) and IgE concentration in an OVA-induced air-pouch-type sensitization model. Taken together, these results indicate that 16D10 is an inhibitor of TSLP production and has an anti-allergic effect. This inhibitory effect is independent of the activation of NF-κB and the Keap1-Nrf2 system. Therefore, 16D10 could be a new type of candidate drug for allergic diseases., (Copyright © 2019 Elsevier B.V. All rights reserved.)
- Published
- 2019
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34. A steroid alkaloid derivative 02F04 upregulates thymic stromal lymphopoietin expression slowly and continuously through a novel Gq/11-ROCK-ERK1/2 signaling pathway in mouse keratinocytes.
- Author
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Weng Y, Wang J, Yang Z, Xi M, Duan J, Guo C, Yin Y, Segawa R, Moriya T, Yonezawa T, Cha BY, Woo JT, Wen A, and Hirasawa N
- Subjects
- Alkaloids chemistry, Animals, Cells, Cultured, Cytokines drug effects, MAP Kinase Signaling System drug effects, Mice, Mitogen-Activated Protein Kinase 3 metabolism, Phosphorylation drug effects, Transcriptional Activation drug effects, Up-Regulation drug effects, Thymic Stromal Lymphopoietin, Alkaloids pharmacology, Cytokines metabolism, Keratinocytes drug effects, Keratinocytes metabolism
- Abstract
Thymic stromal lymphopoietin (TSLP), a master switch of allergic inflammation, plays an important role in the pathogenesis of allergic diseases. Although many compounds upregulate TSLP expression in vivo or in vitro, most of them are pollutants or toxicants. In the previous study, for the first time, we found that a steroid alkaloid derivative 02F04, which has a unique skeletal structure compared with other TSLP-inducing chemicals, significantly induced TSLP production in mouse keratinocytes. However, it is not investigated thoroughly that how 02F04 produces TSLP and why. In this study, we did a detailed investigation on the inducible effect and underlying molecular mechanism of 02F04 on TSLP production. We found that the peak time of TSLP mRNA level induced by 02F04 at 48 h led to a slow and continuous TSLP production in PAM212 cells. Besides, 02F04-induced TSLP production was significantly suppressed by inhibitors of Rho-associated protein kinase (ROCK), guanine nucleotide-binding protein subunit alpha q/11 (Gq/11) and extracellular signal-regulated kinase 1/2 (ERK1/2) at not only protein but also mRNA levels, and by siRNA-mediated knockdown of Gq or G11. This suggested that ROCK, Gq/11 and ERK1/2 signaling pathways were involved in 02F04-induced TSLP production. Increase in the level of p-ERK1/2 induced by 02F04 was suppressed by both inhibitors of ROCK and Gq/11, indicating that ROCK and Gq/11 molecules were located at the upstream of ERK1/2 to regulate 02F04-induced TSLP production. Gq/11 was located at the upstream of ROCK because the specific Gq/11 inhibitor of YM-254890 significantly reduced 02F04-induced actin stress fiber formation. Taken together, 02F04 upregulates a slow and continuous TSLP production through a novel Gq/11-ROCK-ERK1/2 signaling pathway. The thorough understanding the effect and mechanism of 02F04 on TSLP production is expected to supply it as a novel TSLP-regulating compound and a potential new tool for investigating the role of TSLP in allergic disorders., (Copyright © 2019. Published by Elsevier Inc.)
- Published
- 2019
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35. All- Trans Retinoic Acid Enhances Antibody Production by Inducing the Expression of Thymic Stromal Lymphopoietin Protein.
- Author
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Hatayama T, Segawa R, Mizuno N, Eguchi S, Akamatsu H, Fukuda M, Nakata F, Leonard WJ, Hiratsuka M, and Hirasawa N
- Subjects
- Animals, Antigens immunology, Female, Hemagglutinins immunology, Inflammation immunology, Male, Mice, Mice, Inbred BALB C, Mice, Inbred C57BL, Mice, Inbred ICR, Mice, Knockout, Thymic Stromal Lymphopoietin, Antibody Formation immunology, Cytokines immunology, Tretinoin immunology
- Abstract
Many classical vaccines contain whole pathogens and, thus, may occasionally induce adverse effects, such as inflammation. Vaccines containing purified rAgs resolved this problem, but, owing to their low antigenicity, they require adjuvants. Recently, the use of several cytokines, including thymic stromal lymphopoietin (TSLP), has been proposed for this purpose. However, it is difficult to use cytokines as vaccine adjuvants in clinical practice. In this study, we examined the effects of all- trans retinoic acid (atRA) on TSLP production and Ag-induced Ab production. Application of atRA onto the ear lobes of mice selectively induced TSLP production without inducing apparent inflammation. The effects appeared to be regulated via retinoic acid receptors γ and α. Treatment with atRA was observed to enhance OVA-induced specific Ab production; however, this effect was completely absent in TSLP receptor-knockout mice. An enhancement in Ab production was also observed when recombinant hemagglutinin was used as the Ag. In conclusion, atRA was an effective adjuvant through induction of TSLP production. Therefore, we propose that TSLP-inducing low m.w. compounds, such as atRA, may serve as effective adjuvants for next-generation vaccines., (Copyright © 2018 by The American Association of Immunologists, Inc.)
- Published
- 2018
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36. EGFR transactivation is involved in TNF-α-induced expression of thymic stromal lymphopoietin in human keratinocyte cell line.
- Author
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Segawa R, Shigeeda K, Hatayama T, Dong J, Mizuno N, Moriya T, Hiratsuka M, and Hirasawa N
- Subjects
- ADAM Proteins antagonists & inhibitors, Cells, Cultured, Epidermal Growth Factor pharmacology, ErbB Receptors metabolism, Humans, Mitogen-Activated Protein Kinases physiology, Phosphorylation, RNA, Messenger analysis, Thymic Stromal Lymphopoietin, Cytokines genetics, ErbB Receptors genetics, Keratinocytes metabolism, Transcriptional Activation, Tumor Necrosis Factor-alpha pharmacology
- Abstract
Background: Thymic stromal lymphopoietin (TSLP) is an epithelial cell-derived cytokine involved in the pathology of inflammatory skin diseases, such as atopic dermatitis and psoriasis. Tumor necrosis factor (TNF)-α, a key cytokine in inflammatory skin diseases, is a known TSLP inducer. TNF-α activates NF-κB and induces transactivation of epidermal growth factor receptor (EGFR) in epithelial cells. However, the detailed mechanism of TSLP induction by TNF-α has remained unclear., Objective: We investigated the involvement of TNF-α-induced EGFR transactivation in TSLP expression., Methods: HaCaT cells were stimulated with TNF-α or EGF in the presence or absence of an EGFR kinase inhibitor or other signaling inhibitors. The expression of TSLP mRNA was analyzed by RT-PCR and the phosphorylation level of signal proteins was analyzed by western blot. TSLP promoter and NF-κB transcription activities were analyzed by luciferase assay., Results: TNF-α-induced TSLP expression was inhibited by the EGFR kinase inhibitor AG1478. While TSLP expression was induced by EGF, it was inhibited by the MEK inhibitor, U0126. Inhibitors of p38 and ADAM proteases suppressed the TNF-α-induced TSLP expression and EGFR phosphorylation, but not the EGF-induced expression., Conclusion: TNF-α-induced EGFR transactivation results in TSLP induction through ERK activation. The activation of p38 and ADAM proteases mediates TNF-α-induced EGFR phosphorylation. These findings suggested that the TNF-α-induced EGFR transactivation pathway could be a target for the treatment of inflammatory skin diseases., (Copyright © 2017 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.)
- Published
- 2018
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37. Nickel ions bind to HSP90β and enhance HIF-1α-mediated IL-8 expression.
- Author
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Asakawa S, Onodera R, Kasai K, Kishimoto Y, Sato T, Segawa R, Mizuno N, Ogasawara K, Moriya T, Hiratsuka M, and Hirasawa N
- Subjects
- Cell Line, Cell Nucleus drug effects, Cell Nucleus metabolism, Cobalt metabolism, Cobalt pharmacology, HSP90 Heat-Shock Proteins drug effects, Humans, Hypoxia-Inducible Factor 1, alpha Subunit antagonists & inhibitors, Hypoxia-Inducible Factor 1, alpha Subunit drug effects, Monocytes metabolism, Mustard Compounds pharmacology, Phenylpropionates pharmacology, Protein Binding, Toll-Like Receptor 4 drug effects, Toll-Like Receptor 4 metabolism, HSP90 Heat-Shock Proteins metabolism, Hypoxia-Inducible Factor 1, alpha Subunit metabolism, Interleukin-8 biosynthesis, Nickel metabolism, Nickel pharmacology
- Abstract
Nickel ions (Ni
2+ ) eluted from biomedical devices cause inflammation and Ni allergy. Although Ni2+ and Co2+ elicit common effects, Ni2+ induces a generally stronger inflammatory reaction. However, the molecular mechanism by which Ni2+ and Co2+ induce such different responses remains to be elucidated. In the present study, we compared the effects of Ni2+ and Co2+ on the expression of interleukin (IL)-8 in human monocyte THP-1 cells. We report that NiCl2 but not CoCl2 induced the expression of IL-8; in contrast, CoCl2 elicited a higher expression of hypoxia-inducible factor-1α (HIF-1α). The NiCl2 -induced expression of IL-8 in late phase was blocked by a HIF-1α inhibitor, PX-478, indicating that NiCl2 targets additional factors responsible for activating HIF-1α. To identify such targets, proteins that bound preferentially to Ni-NTA beads were analyzed by LC/MS/MS. The analysis yielded heat shock protein 90β (HSP90β) as a possible candidate. Furthermore, Ni2+ reduced the interaction of HSP90β with HIF-1α, and instead promoted the interaction between HIF-1α and HIF-1β, as well as the nuclear localization of HIF-1α. Using various deletion variants, we showed that Ni2+ could bind to the linker domain on HSP90β. These results suggest that HSP90β plays important roles in Ni2+ -induced production of IL-8 and could be a potential target for the regulation of Ni2+ -induced inflammation., (Copyright © 2018 Elsevier B.V. All rights reserved.)- Published
- 2018
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38. Zinc ions have a potential to attenuate both Ni ion uptake and Ni ion-induced inflammation.
- Author
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Onodera R, Asakawa S, Segawa R, Mizuno N, Ogasawara K, Hiratsuka M, and Hirasawa N
- Subjects
- Animals, Biological Transport drug effects, Cell Line, Humans, Inflammation chemically induced, Inflammation drug therapy, Inflammation metabolism, Interleukin-8 biosynthesis, Male, Mice, Zinc therapeutic use, Nickel metabolism, Nickel pharmacology, Zinc pharmacology
- Abstract
Nickel ions (Ni
2+ ) are eluted from various metallic materials, such as medical devices implanted in human tissues. Previous studies have shown that Ni2+ enters inflammatory cells inducing inflammation. However, the regulation of Ni2+ uptake in cells has not yet been reported in detail. In the present study, we investigated the effects of various divalent cations on Ni2+ uptake and Ni2+ -induced interleukin (IL)-8 production in the human monocytic cell line, THP-1. We demonstrated that ZnCl2, MnCl2 , and CoCl2 inhibited the Ni2+ uptake, while CuCl2 , FeCl2 , MgCl2 , and divalent metal transporter (DMT)-1 inhibitor, Chlorazol Black, did not. Furthermore, ZnCl2 inhibited Ni2+ -induced IL-8 production, correlating with the inhibition of Ni2+ uptake. These results suggested that Ni2+ uptake occurred through Zn2+ , Mn2+ , and Co2+ -sensitive transporters and that the inhibition of Ni2+ uptake resulted in the inhibition of IL-8 production. Furthermore, using an Ni wire-implanted mouse model, we found that Ni wire-induced expression of mouse macrophage inflammatory protein-2 (MIP-2) and cyclooxygenase-2 (COX-2) mRNA in the skin tissue surrounding the wire were enhanced by low Zn conditions. These results suggested that the physiological concentration of Zn2+ modulates Ni2+ uptake by inflammatory cells, and a Zn deficient state might increase sensitivity to Ni.- Published
- 2018
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39. Induction of thymic stromal lymphopoietin by a steroid alkaloid derivative in mouse keratinocytes.
- Author
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Weng Y, Mizuno N, Dong J, Segawa R, Yonezawa T, Cha BY, Woo JT, Moriya T, Hiratsuka M, and Hirasawa N
- Subjects
- Alkaloids chemistry, Animals, Cell Line, Cytokines genetics, Gene Expression Regulation, Keratinocytes drug effects, Liver X Receptors chemistry, MAP Kinase Signaling System, Mice, Phosphorylation, Protein Kinase C metabolism, Steroids chemistry, Type C Phospholipases metabolism, Thymic Stromal Lymphopoietin, Alkaloids pharmacology, Cytokines metabolism, Hypersensitivity metabolism, Keratinocytes physiology, Steroids pharmacology
- Abstract
Thymic stromal lymphopoietin (TSLP) plays critical roles in inducing and exacerbating allergic diseases. Chemical compounds that induce TSLP production can enhance sensitization to antigens and exacerbate allergic inflammation. Hence, identifying such chemicals will be important to prevent an increase in allergic diseases. In the present study, we found, for the first time, that a steroid alkaloid derivative, code no. 02F04, concentration and time dependently induced mRNA expression and production of TSLP in a mouse keratinocyte cell line, PAM212. In particular, the activity of 02F04 was selective to TSLP. As an analogue of the liver X receptor (LXR) endogenous ligand, 02F04 rapidly increased ATP-binding cassette transporter A1 (ABCA1) expression by regulating the nuclear receptor of LXR. However, instead of being inhibited by the LXR antagonist, 02F04-induced TSLP production was delayed and markedly suppressed by inhibitors of phospholipase C (PLC), pan-protein kinase C (PKC), PKCδ, Rho-associated protein kinase (ROCK), extracellular signal-regulated kinase (ERK) 1/2, and IκΒ kinase 2 (IKK2). Treatment with 02F04 caused the formation of F-actin filaments surrounding the nucleus of PAM212 cells, which then disappeared following addition of ROCK inhibitor. 02F04 also induced phosphorylation of ERK1/2 from 2h after treatment, with a maximum at 24h, and increased nuclear factor-κB (NF-κB) promoter activity by 1.3-fold. Taken together, these results indicate that 02F04-induced TSLP production is regulated via distinct signal transduction pathways, including PLC, PKC, ROCK, ERK1/2, and NF-κB but not nuclear receptors. 02F04, with a unique skeletal structure in inducing TSLP production, can represent a potential new tool for investigating the role of TSLP in allergic diseases., (Copyright © 2017 Elsevier B.V. All rights reserved.)
- Published
- 2018
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40. LPS priming in early life decreases antigen uptake of dendritic cells via NO production.
- Author
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Mizuno N, Sasaki Y, Segawa R, Asakawa S, Hiratsuka M, and Hirasawa N
- Subjects
- Aging immunology, Animals, Antigen Presentation, Antigens metabolism, CD11c Antigen metabolism, Cell Movement, Disease Models, Animal, Endocytosis, Environmental Exposure adverse effects, Humans, Hygiene Hypothesis, Immunization, Male, Mice, Mice, Inbred BALB C, Dendritic Cells immunology, Hypersensitivity immunology, Infections immunology, Lipopolysaccharides immunology, Nitric Oxide metabolism
- Abstract
Immunological mechanisms of hygiene hypothesis are expected to develop a novel strategy for allergy prevention. Although a large number of studies has investigated the relation between allergies and infection, little is known about the influence of the exposure to infections on antigen uptake by dendritic cells (DCs). In this study, we examined the effect of lipopolysaccharide (LPS) priming in early life on the antigen uptake ability of DCs by using an original mouse model. LPS priming in juvenile mice decreased the migration of antigen-capturing CD11c
+ cells in the lymph nodes, but not in aged mice. Besides, the bone marrow-derived DCs (BMDCs) from juvenile LPS-primed mice had the poor antigen uptake ability, and constitutively produced NO through the inducible nitric oxide synthase (iNOS). Interestingly, the LPS priming-induced poor antigen uptake of BMDCs was mimicked by the NO donor, and recovered by the iNOS inhibitor. Additionally, LPS priming in juvenile mice prevented the allergic reactions, but not in aged mice. Our results suggested that an exposure to infections in early life prevents allergy through the alteration of the BM cells fate that is to induce the differentiation of BM cells into inhibitory DCs such as NO-producing DCs., (Copyright © 2017 Elsevier GmbH. All rights reserved.)- Published
- 2018
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41. Induced histamine regulates Ni elution from an implanted Ni wire in mice by downregulating neutrophil migration.
- Author
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Kishimoto Y, Asakawa S, Sato T, Takano T, Nakajyo T, Mizuno N, Segawa R, Yoshikawa T, Hiratsuka M, Yanai K, Ohtsu H, and Hirasawa N
- Subjects
- Animals, Cells, Cultured, Chemokine CCL2 genetics, Chemokine CCL2 metabolism, Chemokine CXCL2 genetics, Chemokine CXCL2 metabolism, Down-Regulation, Gene Expression drug effects, Histamine pharmacology, Histidine Decarboxylase genetics, Histidine Decarboxylase metabolism, Inflammation etiology, Inflammation genetics, Macrophages drug effects, Male, Mice, Mice, Inbred C57BL, Mice, Knockout, Nickel adverse effects, Nickel pharmacology, Prostheses and Implants, Receptors, Histamine H2 genetics, Cell Movement, Histamine metabolism, Inflammation metabolism, Neutrophils physiology, Nickel metabolism, RNA, Messenger metabolism
- Abstract
Histamine regulates various inflammatory reactions. We have reported that the expression of histidine decarboxylase (HDC) was induced by subcutaneous implantation of nickel (Ni) wire. However, the source and functions of histamine in Ni elution and Ni wire-induced inflammation have not been completely studied. We aimed to elucidate the effects of de novo synthesized histamine on leucocyte infiltration and Ni elution. Implantation of Ni wire induced an increase in the Ni ion content of the surrounding tissues and serum and in the mRNA levels of HDC, a histamine-producing enzyme, macrophage inflammatory protein-2 (MIP-2), a chemoattractant for neutrophils, and monocyte chemoattractant protein-1 (MCP-1), a chemoattractant for monocytes. The Ni wire induced HDC expression even in mast cell-deficient WBB6F1-W/W
V mice. In HDC knockout (HDC KO) mice, the Ni wire-induced increase in MIP-2 mRNA expression was significantly higher than that in wild-type mice but not MCP-1. MIP-2 expression was enhanced in histamine H2 receptor knockout (H2R KO) mice but not in WBB6F1-W/WV mice. Histamine inhibited NiCl2 -induced MIP-2 mRNA expression in mouse bone marrow-derived macrophages (BMDMs) obtained from wild-type mice; this inhibition was not observed in BMDMs from H2R KO mice. Ni elution increased in HDC KO mice, in which leucocyte infiltration also increased, and was suppressed in mice treated with neutrophil-specific antibody. These results suggest that the Ni wire induced HDC expression in non-mast cells and that, in the chronic phase of inflammation, endogenous histamine reduced Ni elution, probably through regulation of MIP-2 expression and neutrophil migration., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)- Published
- 2017
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42. Pentanoic acid induces thymic stromal lymphopoietin production through G q/11 and Rho-associated protein kinase signaling pathway in keratinocytes.
- Author
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Mizuno N, Abe K, Morishita Y, Yamashita S, Segawa R, Dong J, Moriya T, Hiratsuka M, and Hirasawa N
- Subjects
- Amides pharmacology, Animals, Cells, Cultured, GTP-Binding Protein alpha Subunits, Gq-G11 genetics, Humans, Keratinocytes physiology, Mice, Mice, Inbred BALB C, Pentanoic Acids immunology, Peptides, Cyclic pharmacology, Pyridines pharmacology, RNA, Small Interfering genetics, Signal Transduction, Skin pathology, rho-Associated Kinases metabolism, Thymic Stromal Lymphopoietin, Cytokines metabolism, GTP-Binding Protein alpha Subunits, Gq-G11 metabolism, Hypersensitivity immunology, Keratinocytes drug effects, Pentanoic Acids metabolism, Skin immunology
- Abstract
Thymic stromal lymphopoietin (TSLP) plays an important role in allergic skin inflammation. Short-chain fatty acids (SCFAs), including pentanoic acid, are products of bacterial metabolism and are associated with allergic skin disorders. However, whether SCFAs induce TSLP production is still unclear. In this study, we evaluated the effect of SCFAs on TSLP production and found that pentanoic acid was the most efficacious of the tested SCFAs. The G
q/11 inhibitor YM-254890 and the Rho-associated protein kinase (ROCK) inhibitor Y-27632 inhibited pentanoic acid-induced TSLP production, as did transfection with Gq/11 siRNA. These results suggested that pentanoic acid-induced TSLP production was mediated by Gq/11 and ROCK, providing insights into a novel TSLP production pathway in keratinocytes. The novel mechanism of TSLP production is expected to support the development of TSLP-regulating approaches in allergic skin disorders., (Copyright © 2017 Elsevier B.V. All rights reserved.)- Published
- 2017
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43. Endometrial adenocarcinoma with choriocarcinomatous differentiation in the uterus of a goat.
- Author
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Kawashima M, Segawa R, Yoshida T, Murayama H, Nagahara R, Kimura M, Endo N, Tanaka T, and Shibutani M
- Subjects
- Adenocarcinoma pathology, Animals, Choriocarcinoma pathology, Endometrial Neoplasms pathology, Female, Goat Diseases diagnosis, Goats, Uterine Neoplasms pathology, Adenocarcinoma veterinary, Choriocarcinoma veterinary, Endometrial Neoplasms veterinary, Goat Diseases pathology, Uterine Neoplasms veterinary
- Abstract
An 11-year-old female goat had invasive and metastatic endometrial adenocarcinoma in the uterus. There was a notable proliferation of endometrial epithelial cells in a tubular growth pattern, with a desmoplastic response. The endometrial epithelial tumor cells metastasized to the kidney, liver and lung. In contrast to the primary and metastatic tumor cells, pleomorphic tumor cells with a choriocarcinoma-like growth pattern infiltrated the mesometrium. Cell proliferation activity was high in both types of tumor cells. Both types of tumor cells expressed cytokeratins AE1/AE3, 7 and CAM5.2; choriocarcinomatous cells also had positive immunoreactions to human chorionic gonadotropin, human placental alkaline phosphatase and α-inhibin. The present case was diagnosed as endometrial adenocarcinoma with choriocarcinomatous differentiation.
- Published
- 2017
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44. Lipopolysaccharide-Activated Leukocytes Enhance Thymic Stromal Lymphopoietin Production in a Mouse Air-Pouch-Type Inflammation Model.
- Author
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Segawa R, Mizuno N, Hatayama T, Jiangxu D, Hiratsuka M, Endo Y, and Hirasawa N
- Subjects
- Animals, Cell Line, Disease Models, Animal, Inflammation metabolism, Inflammation pathology, Interleukin-1beta biosynthesis, Interleukin-1beta physiology, Keratinocytes, Leukocytes physiology, Lipopolysaccharides pharmacology, Mice, Toll-Like Receptor 4 metabolism, Tumor Necrosis Factor-alpha biosynthesis, Tumor Necrosis Factor-alpha physiology, Thymic Stromal Lymphopoietin, Cytokines biosynthesis, Leukocytes metabolism
- Abstract
Thymic stromal lymphopoietin (TSLP) is a key cytokine that exacerbates allergic and fibrotic reactions. Several microbes and virus components have been shown to induce TSLP production, mainly in epithelial cells. TLR4 activators, such as lipopolysaccharide (LPS), induce TSLP production in vivo, although the underlying mechanisms remain unclear. In this study, we investigated the contribution of LPS-activated leukocytes to the production of TSLP in a mouse air-pouch-type inflammation model. LPS induced the production of TSLP in this model but not in the mouse keratinocyte cell line PAM212. Transfer of the infiltrated leukocytes collected from an LPS-injected air pouch to the air pouch of another mouse enhanced TSLP production. Further, the LPS-activated leukocytes produced tumor necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1β); a deficiency in these cytokines attenuated the LPS-induced production of TSLP. TSLP production was induced by TNF-α and enhanced by IL-1β and LPS in the PAM212 cells. These results demonstrated that TNF-α and IL-1β, which are partly produced by LPS-activated leukocytes, contribute to TSLP production via TLR4 activation in vivo.
- Published
- 2016
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45. Inhibitory effects of nicotine derived from cigarette smoke on thymic stromal lymphopoietin production in epidermal keratinocytes.
- Author
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Dong J, Segawa R, Mizuno N, Hiratsuka M, and Hirasawa N
- Subjects
- Animals, Cell Line, Cytokines biosynthesis, Enzyme Activation drug effects, Enzyme Inhibitors pharmacology, Epidermal Cells, Epidermis drug effects, Keratinocytes metabolism, MAP Kinase Signaling System genetics, Mice, NF-kappa B genetics, Real-Time Polymerase Chain Reaction, Smoking, Thymic Stromal Lymphopoietin, Cytokines genetics, Gene Expression Regulation drug effects, Keratinocytes drug effects, Nicotine toxicity
- Abstract
Thymic stromal lymphopoietin (TSLP) is regarded as the main factor responsible for the pathogenesis of atopic dermatitis (AD). Cigarette smoke is an aggravating factor for allergies, but has been reported to decrease the risk of AD. In the present study, we evaluated the role of nicotine, the main constituent in cigarette smoke extract, and its underlying mechanism of action in the regulation of TSLP expression. We found that nicotine significantly inhibited 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced TSLP expression in BALB/c mice and the mouse keratinocyte cell line PAM212. Nicotine inhibition of TSLP production was abolished by pretreatments with α7 nicotinic acetylcholine receptor (α7 nAChR) antagonists, AMP-activated protein kinase (AMPK) inhibitor, and phosphoinositide 3-kinase (PI3K) inhibitors. The same inhibitors abolished inhibition of nuclear factor-κB (NF-κB) activation by nicotine. These results suggest that nicotine inhibits the expression of TSLP by suppressing the activation of NF-κB through the α7 nAChR-PI3K-AMPK signaling pathway., (Copyright © 2016 Elsevier Inc. All rights reserved.)
- Published
- 2016
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46. [Successful Stent-Assisted Coil Embolization of Fusiform Aneurysm in P2 Segment of Posterior Cerebral Artery:A Case Report].
- Author
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Segawa R, Kashiwazaki D, Akioka N, Koh M, Kuwayama N, and Kuroda S
- Subjects
- Adult, Cerebral Angiography, Embolization, Therapeutic, Female, Humans, Imaging, Three-Dimensional, Magnetic Resonance Imaging, Multimodal Imaging, Intracranial Aneurysm surgery, Posterior Cerebral Artery, Stents
- Abstract
We report a case of a fusiform aneurysm in the P2 segment of the posterior cerebral artery treated with stent-assisted coil embolization. A 44-year-old woman presented with an unruptured fusiform aneurysm in the left posterior cerebral artery. Stent-assisted coil embolization was performed using a "down-the-barrel" view to preserve the parent artery. The postoperative course was uneventful, and MRI showed no evidence of cerebral infarct. The patient was discharged 12 days after surgery, with no neurological deficit. Complete occlusion of the aneurysm and patency of the parent artery were observed on MR angiography at a 3-months follow up. Stent-assisted coil embolization can therefore be an effective alternative to parent artery occlusion in P2 segment fusiform aneurysms of the posterior cerebral artery.
- Published
- 2016
- Full Text
- View/download PDF
47. Visualization of Tumor Necrosis Factor-α Distributions Within Pressure Ulcer Tissue Using the Wound Blotting Method: A Case Report and Discussion.
- Author
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Kitamura A, Nakagami G, Yoshida M, Noguchi H, Nishijima Y, Minematsu T, Naito A, Sugawara J, Shibayama H, Takahashi K, Hakuta A, Umemoto J, Terada N, Segawa R, Mori T, and Sanada H
- Abstract
Wound blotting can be used to visualize the protein distribution on a wound bed through protein collection by attaching a nitrocellulose membrane to the wound surface. This study checked for consistency between the protein distributions determined by wound blotting and those determined by removal of the tissue. A patient who was planning to undergo surgical debridement of an ulcer in the sacral region that was caused by lying down for a long period after a cerebral hemorrhage was recruited in Fujisawa City Hospital, Kanagawa, Japan. Wound blotting was performed just prior to surgical debridement and the debrided tissue embedded in paraffin. The ulcer, which had a 2.9 cm major axis, was divided into 20 areas approximately 0.35 cm2 each, and the consistency of tumor necrosis factor-α positivity between the wound blotting samples and tissue sections was examined in each area. The sensitivity and specificity of wound blotting were 89% and 82%, respectively. This wound blotting method noninvasively revealed the protein distributions within the wound tissue.
- Published
- 2014
48. Tumor suppression effects of bilberry extracts and enzymatically modified isoquercitrin in early preneoplastic liver cell lesions induced by piperonyl butoxide promotion in a two-stage rat hepatocarcinogenesis model.
- Author
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Hara S, Morita R, Ogawa T, Segawa R, Takimoto N, Suzuki K, Hamadate N, Hayashi SM, Odachi A, Ogiwara I, Shibusawa S, Yoshida T, and Shibutani M
- Subjects
- Animals, Anticarcinogenic Agents administration & dosage, Apoptosis drug effects, Cell Proliferation drug effects, Cocarcinogenesis, Diethylnitrosamine toxicity, Glycosylation, Liver Neoplasms, Experimental chemically induced, Liver Neoplasms, Experimental metabolism, Liver Neoplasms, Experimental pathology, Male, Oxidative Stress drug effects, Plant Extracts administration & dosage, Plant Extracts isolation & purification, Precancerous Conditions chemically induced, Precancerous Conditions metabolism, Precancerous Conditions pathology, Quercetin administration & dosage, Quercetin isolation & purification, Quercetin therapeutic use, Rats, Inbred F344, Anticarcinogenic Agents therapeutic use, Liver Neoplasms, Experimental prevention & control, Piperonyl Butoxide toxicity, Plant Extracts therapeutic use, Precancerous Conditions prevention & control, Quercetin analogs & derivatives, Vaccinium myrtillus chemistry
- Abstract
To investigate the protective effect of bilberry extracts (BBE) and enzymatically modified isoquercitrin (EMIQ) on the hepatocarcinogenic process involving oxidative stress responses, we used a two-stage hepatocarcinogenesis model in N-diethylnitrosamine-initiated and piperonyl butoxide (PBO)-promoted rats. We examined the modifying effect of co-administration with BBE or EMIQ on the liver tissue environment including oxidative stress responses, cell proliferation and apoptosis, and phosphatase and tensin homolog (PTEN)/Akt and transforming growth factor (TGF)-β/Smad signalings on the induction mechanism of preneoplastic lesions during early stages of hepatocellular tumor promotion. PBO increased the numbers and area of glutathione S-transferase placental form (GST-P)(+) liver cell foci and the numbers of Ki-67(+) proliferating cells within GST-P(+) foci. Co-administration of BBE or EMIQ suppressed these effects with the reductions of GST-P(+) foci (area) to 48.9-49.4% and Ki-67(+) cells to 55.5-61.4% of the PBO-promoted cases. Neither BBE nor EMIQ decreased microsomal reactive oxygen species induced by PBO. However, only EMIQ suppressed the level of thiobarbituric acid-reactive substances to 78.4% of the PBO-promoted cases. PBO increased the incidences of phospho-PTEN(-) foci, phospho-Akt substrate(+) foci, phospho-Smad3(-) foci and Smad4(-) foci in GST-P(+) foci. Both BBE and EMIQ decreased the incidences of phospho-PTEN(-) foci in GST-P(+) foci to 59.8-72.2% and Smad4(-) foci to 62.4-71.5% of the PBO-promoted cases, and BBE also suppressed the incidence of phospho-Akt substrate(+) foci in GST-P(+) foci to 75.2-75.7% of the PBO-promoted cases. These results suggest that PBO-induced tumor promotion involves facilitation of PTEN/Akt and disruptive TGF-β/Smad signalings without relation to oxidative stress responses, but this promotion was suppressed by co-treatment with BBE or EMIQ through suppression of cell proliferation activity of preneoplastic liver cells., (Copyright © 2014 Elsevier GmbH. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
49. Immunohistochemical characterization of multicentric hepatocholangiocellular adenoma in a pig.
- Author
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Segawa R, Fujii Y, Ogawa T, Takimoto N, Hara S, Murakami T, Suzuki K, and Shibutani M
- Abstract
Three spherical opaque-white tumor nodules were found in close proximity to each other in the liver of a breeding sow, postslaughter, at a veterinary food inspection. The tumor nodules were circumscribed and histologically consisted of discrete hepatocellular and cholangiocellular nests, in association with polygonal-to-oval-shaped cells with slight cellular atypia. Immunohistochemically, all cellular components were negative for carcinoembryonic antigen, but positive for p53. Both cholangiocytes and oval-shaped cells were immunoreactive to anti-cytokeratin antibodies AE1/AE3 and MNF116. In addition, cholangiocytes were exclusively immunoreactive to anti-cytokeratin antibody CAM5.2, and hepatocytes were positive for MNF116 and hepatocyte paraffin 1. All neoplastic cells were positive for the hepatic progenitor cell markers, α-1-fetoprotein, sal-like protein 4, and epithelial cell adhesion molecule. From these results, the present case was diagnosed as hepatocholangiocellular adenoma, arising from epithelial cells of the canals of Hering., (© 2014 The Author(s).)
- Published
- 2014
- Full Text
- View/download PDF
50. Maternal single injection of N-methyl-N-nitrosourea to cause microcephaly in offspring induces transient aberration of hippocampal neurogenesis in mice.
- Author
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Takimoto N, Wang L, Itahashi M, Ogawa T, Segawa R, Hara S, Murakami T, Suzuki K, and Shibutani M
- Subjects
- Animals, Apoptosis drug effects, Cell Adhesion Molecules, Neuronal genetics, Cell Adhesion Molecules, Neuronal metabolism, Cell Lineage, Cell Proliferation drug effects, Doublecortin Domain Proteins, Doublecortin Protein, Extracellular Matrix Proteins genetics, Extracellular Matrix Proteins metabolism, Female, Gestational Age, Hippocampus metabolism, Hippocampus pathology, Hippocampus physiopathology, Injections, Intraperitoneal, Interneurons drug effects, Interneurons metabolism, Interneurons pathology, Male, Maternal Exposure, Mice, Mice, Inbred ICR, Microcephaly genetics, Microcephaly metabolism, Microcephaly pathology, Microcephaly physiopathology, Microtubule-Associated Proteins metabolism, Nerve Tissue Proteins genetics, Nerve Tissue Proteins metabolism, Neural Stem Cells metabolism, Neural Stem Cells pathology, Neuropeptides metabolism, Parvalbumins genetics, Parvalbumins metabolism, Pregnancy, Proto-Oncogene Proteins c-bcl-2 genetics, Proto-Oncogene Proteins c-bcl-2 metabolism, Reelin Protein, Serine Endopeptidases genetics, Serine Endopeptidases metabolism, Time Factors, Alkylating Agents toxicity, Hippocampus drug effects, Methylnitrosourea toxicity, Microcephaly chemically induced, Neural Stem Cells drug effects, Neurogenesis drug effects, Prenatal Exposure Delayed Effects
- Abstract
N-Methyl-N-nitrosourea (MNU) is an alkylating agent having antiproliferative cytotoxity targeting the neural stem/progenitor cells to cause microcephaly by maternal exposure. This study investigated the effect of transient exposure to MNU on the process of hippocampal neurogenesis in later life using mice. Pregnant mice received a single injection of MNU at 0, 5 and 10 mg/kg body weight, intraperitoneally on gestational day 14, and their offspring were examined on postnatal day (PND) 21 and PND 77. On PND 21, offspring displayed microcephaly and hippocampal formation hypoplasia at 10 mg/kg, decrease of doublecortin (Dcx)(+) cells in the dentate subgranular zone from 5mg/kg, and decrease of TUNEL(+) apoptotic cells and increase of transcript expression of anti-apoptotic Bcl-2 at 10 mg/kg in the dentate gyrus. In the dentate hilus, numbers of reelin(+) or parvalbumin (Pvalb)(+) interneurons or neuron-specific nuclear protein(+) neurons increased at 10 mg/kg. Microcephaly and hippocampal formation hypoplasia continued through PND 77 at 10 mg/kg. Thus, apart from the massive cell killing at the migratory stream causing microcephaly, MNU may decrease Dcx(+) cells reflecting disruption of the differentiation process of late-stage neuronal progenitors and immature granule cells through defective molecular functions by gene mutations. Increase of reelin(+) and Pvalb(+) cells may reflect the disruption of neurogenesis and following neuronal migration. All of the granule cell lineage and interneuron changes disappeared at the adult stage on PND 77 suggesting that MNU mainly targets transient populations of highly proliferative progenitor cells but hardly affects their stem cells having self-renewal ability., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
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