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1.
Lab Invest ; 104(2): 100299, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38013118

RESUMO

The pathogenesis of malignant mesothelioma (MM) has been extensively investigated, focusing on stress derived from reactive oxygen species. We aimed to identify diagnostic biomarkers of MM by analyzing proteins in formalin-fixed paraffin-embedded specimens using liquid chromatography-mass spectrometry. We extracted proteins from formalin-fixed paraffin-embedded sections of MM tissues (n = 7) and compared their profiles with those of benign mesothelial tissues (n = 4) and alveolar tissue (n = 1). Proteomic data were statistically assessed and profiled using principal component analysis. We were successful in the classification of MM and healthy tissue. The levels of superoxide dismutase 2 (SOD2), an enzyme that converts superoxide anion into oxygen and hydrogen peroxide, and thioredoxin (TXN), which plays a crucial role in reducing disulfide bonds in proteins, primarily contributed to the classification. Other redox-related proteins, such as pyruvate dehydrogenase subunit X, and ceruloplasmin also contributed to the classification. Protein-protein interaction analysis demonstrated that these proteins play essential roles in MM pathogenesis. Immunohistochemistry revealed that TXN levels were significantly lower, whereas SOD2 levels were significantly higher in MM and lung cancer tissues than in controls. Proteomic profiling suggested that MM tissues experienced increased exposure to hydrogen peroxide and other reactive oxygen species. Combining immunohistochemistry for TXN and SOD2 allows for differentiation among MM, lung cancer, and control tissues; hence, TXN and SOD2 may be promising MM biomarkers and therapeutic targets.


Assuntos
Neoplasias Pulmonares , Mesotelioma Maligno , Superóxido Dismutase , Humanos , Imuno-Histoquímica , Proteômica/métodos , Formaldeído/química , Inclusão em Parafina/métodos , Peróxido de Hidrogênio , Espécies Reativas de Oxigênio , Biomarcadores , Tiorredoxinas , Neoplasias Pulmonares/diagnóstico
2.
J Pathol ; 260(4): 478-492, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37310065

RESUMO

Biliary tract cancer (BTC) has poor prognosis. The Notch receptor is aberrantly expressed in extrahepatic cholangiocarcinoma (eCCA). However, the role of Notch signaling in the initiation and progression of eCCA and gallbladder (GB) cancer remains unknown. Therefore, we investigated the functional role of Notch signaling during tumorigenesis of the extrahepatic bile duct (EHBD) and GB. Activation of Notch signaling and oncogenic Kras resulted in the development of biliary intraepithelial neoplasia (BilINs) in the EHBD and GB, which were premalignant lesions that progressed to adenocarcinoma in mice. The expression of genes involved in the mTORC1 pathway was increased in biliary spheroids from Hnf1b-CreERT2; KrasLSL-G12D ; Rosa26LSL-NotchIC mice and inhibition of the mTORC1 pathway suppressed spheroid growth. Additionally, simultaneous activation of the PI3K-AKT and Notch pathways in EHBD and GB induced biliary cancer development in mice. Consistent with this, we observed a significant correlation between activated NOTCH1 and phosphorylated Ribosomal Protein S6 (p-S6) expression in human eCCA. Furthermore, inhibition of the mTORC1 pathway suppressed the growth of Notch-activated human biliary cancer cells in vitro and in vivo. Mechanistically, the Kras/Notch-Myc axis activated mTORC1 through TSC2 phosphorylation in mutant biliary spheroids. These data indicate that inhibition of the mTORC1 pathway could be an effective treatment strategy for Notch-activated human eCCA. © 2023 The Pathological Society of Great Britain and Ireland.


Assuntos
Neoplasias dos Ductos Biliares , Neoplasias do Sistema Biliar , Carcinoma in Situ , Colangiocarcinoma , Humanos , Camundongos , Animais , Proteínas Proto-Oncogênicas c-akt , Alvo Mecanístico do Complexo 1 de Rapamicina , Fosfatidilinositol 3-Quinases , Colangiocarcinoma/patologia , Carcinoma in Situ/patologia , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologia
3.
Entropy (Basel) ; 26(4)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38667878

RESUMO

Recent advancements in information thermodynamics have revealed that information can be directly converted into mechanical work. Specifically, RNA transcription and nanopore sequencing serve as prime examples of this conversion, by reading information from a DNA template. This paper introduces an information thermodynamic model in which these molecular motors can move along the DNA template by converting the information read from the template DNA into their own motion. This process is a stochastic one, characterized by significant fluctuations in forward movement and is described by the Fokker-Planck equation, based on drift velocity and diffusion coefficients. In the current study, it is hypothesized that by utilizing the sequence information of the template DNA as mutual information, the fluctuations can be reduced, thereby biasing the forward movement on DNA and, consequently, reducing reading errors. Further research into the conversion of biological information by molecular motors could unveil new applications, insights, and important findings regarding the characteristics of information processing in biology.

4.
Mod Rheumatol ; 34(3): 523-529, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37300805

RESUMO

OBJECTIVES: Decreased sialylation of IgG-Fc glycans has been reported in autoimmune diseases, but its role in systemic lupus erythematosus (SLE) is not fully understood. In this study, we examined the pathogenicity of IgG desialylation and its association with Th17 in SLE using an animal model. METHODS: B6SKG mice, which develop lupus-like systemic autoimmunity due to the ZAP70 mutation, were used to investigate the pathogenicity of IgG desialylation. The proportion of sialylated IgG was compared between B6SKG and wild-type mice with or without ß-glucan treatment-induced Th17 expansion. Anti-interleukin (IL)-23 and anti-IL-17 antibodies were used to examine the role of Th17 cells in IgG glycosylation. Activation-induced cytidine deaminase-specific St6gal1 conditionally knockout (cKO) mice were generated to examine the direct effect of IgG desialylation. RESULTS: The proportions of sialylated IgG were similar between B6SKG and wild-type mice in the steady state. However, IgG desialylation was observed after ß-glucan-induced Th17 expansion, and nephropathy also worsened in B6SKG mice. Anti-IL-23/17 treatment suppressed IgG desialylation and nephropathy. Glomerular atrophy was observed in the cKO mice, suggesting that IgG desialylation is directly involved in disease exacerbation. CONCLUSIONS: IgG desialylation contributes to the progression of nephropathy, which is ameliorated by blocking IL-17A or IL-23 in an SLE mouse model.


Assuntos
Lúpus Eritematoso Sistêmico , beta-Glucanas , Camundongos , Animais , Células Th17 , Virulência , Lúpus Eritematoso Sistêmico/genética , Modelos Animais de Doenças , Imunoglobulina G
5.
Gastroenterology ; 163(2): 466-480.e6, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35483445

RESUMO

BACKGROUND & AIMS: Pancreatic ductal adenocarcinoma (PDAC) arises from several types of premalignant lesions, including intraductal tubulopapillary neoplasm (ITPN); however, the molecular pathogenesis of ITPN remains unknown. METHODS: We performed studies with Hnf1b-CreERT2; Ptenf/f; Arid1af/f mice to investigate the consequence of genetic deletion of Arid1a in adult pancreatic ductal cells in the context of oncogenic PI3K/Akt pathway activation. RESULTS: Simultaneous deletion of Arid1a and Pten in pancreatic ductal cells resulted in the development of ITPN, which progressed to PDAC, in mice. Simultaneous loss of Arid1a and Pten induced dedifferentiation of pancreatic ductal cells and Yes-associated protein 1/Transcriptional coactivator with PDZ-binding motif (YAP/TAZ) pathway activation. Consistent with the mouse data, TAZ expression was found elevated in human ITPNs and ITPN-derived PDACs but not in human intraductal papillary mucinous neoplasms, indicating that activation of the TAZ pathway is a distinctive feature of ITPN. Furthermore, pharmacological inhibition of the YAP/TAZ pathway suppressed the dedifferentiation of pancreatic ductal cells and development of ITPN in Arid1a and Pten double-knockout mice. CONCLUSION: Concurrent loss of Arid1a and Pten in adult pancreatic ductal cells induced ITPN and ITPN-derived PDAC in mice through aberrant activation of the YAP/TAZ pathway, and inhibition of the YAP/TAZ pathway prevented the development of ITPN. These findings provide novel insights into the pathogenesis of ITPN-derived PDAC and highlight the YAP/TAZ pathway as a potential therapeutic target.


Assuntos
Carcinoma Ductal Pancreático , Proteínas de Ligação a DNA , PTEN Fosfo-Hidrolase , Neoplasias Pancreáticas , Fatores de Transcrição , Animais , Carcinoma Ductal Pancreático/patologia , Proteínas de Ligação a DNA/genética , Humanos , Camundongos , PTEN Fosfo-Hidrolase/genética , Ductos Pancreáticos/patologia , Neoplasias Pancreáticas/patologia , Fosfatidilinositol 3-Quinases , Fatores de Transcrição/genética , Neoplasias Pancreáticas
6.
Clin Proteomics ; 20(1): 36, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37705009

RESUMO

BACKGROUND: The molecular pathology of diffuse large B cell lymphoma (DLBCL) has been extensively studied. Among DLBCL subtypes, the prognosis of CD5-positive DLBCL is worse than that of CD5-negative DLBCL, considering the central nervous system relapse and poor response to R-CHOP therapy. However, the molecular mechanisms underlying the tumorigenesis and progression of CD5-positive DLBCL remain unknown. METHODS: To identify molecular markers that can be targeted for treating DLBCL, a proteomic study was performed using liquid chromatography-mass spectrometry with chemically pretreated formalin-fixed paraffin-embedded specimens from CD5-positive (n = 5) and CD5-negative DLBCL patients (n = 6). RESULTS: Twenty-one proteins showed significant downregulation in CD5-positive DLBCL compared to CD5-negative DLBCL. Principal component analysis of protein expression profiling in CD5-positive and CD5-negative DLBCL revealed that DNAJB1, DDX3X, and BTK, which is one of the B cell phenotypic proteins, were the most significantly downregulated proteins and served as biomarkers that distinguished both groups. Additionally, a set of immunoglobulins, including IgG4, exhibited significant downregulation. Immunohistochemistry analysis for BTK demonstrated reduced staining in CD5-positive DLBCL compared to CD5-negative DLBCL. CONCLUSIONS: In conclusion, DNAJB1 and DDX3X, BTK, and a set of immunoglobulins are promising biomarkers. Probably, the suppression of BCR signaling is the unique phenotype of CD5-positive DLBCL. This formalin-fixed paraffin-embedded (FFPE)-based profiling may help to develop novel therapeutic molecularly targeted drugs for treating DLBCL.

7.
Hepatol Res ; 53(2): 145-159, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36149410

RESUMO

AIM: Sinusoidal obstruction syndrome (SOS) induced by oxaliplatin-including chemotherapies (OXCx) is associated with impaired hepatic reserve and higher morbidity after hepatic resection. However, in the absence of an appropriate animal experimental model, little is known about its pathophysiology. This study aimed to establish a clinically relevant reproducible model of FOLFOX-induced SOS and to compare the clinical/histopathological features between the clinical and animal SOS settings. METHODS: We performed clinical/pathological analyses of colorectal liver metastasis (CRLM) patients who underwent hepatectomy with/without preoperative treatment of FOLFOX (n = 22/18). Male micro-minipigs were treated with 50% of the standard human dosage of the FOLFOX regimen. RESULTS: In contrast to the monocrotaline-induced SOS model in rats, hepatomegaly, ascites, congestion, and coagulative necrosis of hepatocytes were absent in patients with CRLM with OXCx pretreatment and OXCx-treated micro-minipigs. In parallel to CRLM cases with OXCx pretreatment, OXCx-challenged micro-minipigs exhibited deteriorated indocyanine green clearance, morphological alteration of liver sinusoidal endothelial cells, and upregulated matrix metalloproteinase-9. Using our novel porcine SOS model, we identified the hepatoprotective influence of recombinant human soluble thrombomodulin in OXCx-SOS. CONCLUSIONS: With distinct differences between monocrotaline-induced rat SOS and human/pig OXCx-SOS, our pig OXCx-SOS model serves as a preclinical platform for future investigations to dissect the pathophysiology of OXCx-SOS and seek preventive strategies.

8.
Entropy (Basel) ; 25(2)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36832692

RESUMO

Queuing networks (QNs) are essential models in operations research, with applications in cloud computing and healthcare systems. However, few studies have analyzed the cell's biological signal transduction using QN theory. This study entailed the modeling of signal transduction as an open Jackson's QN (JQN) to theoretically determine cell signal transduction, under the assumption that the signal mediator queues in the cytoplasm, and the mediator is exchanged from one signaling molecule to another through interactions between the signaling molecules. Each signaling molecule was regarded as a network node in the JQN. The JQN Kullback-Leibler divergence (KLD) was defined using the ratio of the queuing time (λ) to the exchange time (µ), λ/µ. The mitogen-activated protein kinase (MAPK) signal-cascade model was applied, and the KLD rate per signal-transduction-period was shown to be conserved when the KLD was maximized. Our experimental study on MAPK cascade supported this conclusion. This result is similar to the entropy-rate conservation of chemical kinetics and entropy coding reported in our previous studies. Thus, JQN can be used as a novel framework to analyze signal transduction.

9.
Proc Natl Acad Sci U S A ; 116(5): 1704-1713, 2019 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-30635419

RESUMO

Inactivating mutations of Arid1a, a subunit of the Switch/sucrose nonfermentable chromatin remodeling complex, have been reported in multiple human cancers. Intestinal deletion of Arid1a has been reported to induce colorectal cancer in mice; however, its functional role in intestinal homeostasis remains unclear. We investigated the functional role of Arid1a in intestinal homeostasis in mice. We found that intestinal deletion of Arid1a results in loss of intestinal stem cells (ISCs), decreased Paneth and goblet cells, disorganized crypt-villous structures, and increased apoptosis in adult mice. Spheroids did not develop from intestinal epithelial cells deficient for Arid1a Lineage-tracing experiments revealed that Arid1a deletion in Lgr5+ ISCs leads to impaired self-renewal of Lgr5+ ISCs but does not perturb intestinal homeostasis. The Wnt signaling pathway, including Wnt agonists, receptors, and target genes, was strikingly down-regulated in Arid1a-deficient intestines. We found that Arid1a directly binds to the Sox9 promoter to support its expression. Remarkably, overexpression of Sox9 in intestinal epithelial cells abrogated the above phenotypes, although Sox9 overexpression in intestinal epithelial cells did not restore the expression levels of Wnt agonist and receptor genes. Furthermore, Sox9 overexpression permitted development of spheroids from Arid1a-deficient intestinal epithelial cells. In addition, deletion of Arid1a concomitant with Sox9 overexpression in Lgr5+ ISCs restores self-renewal in Arid1a-deleted Lgr5+ ISCs. These results indicate that Arid1a is indispensable for the maintenance of ISCs and intestinal homeostasis in mice. Mechanistically, this is mainly mediated by Sox9. Our data provide insights into the molecular mechanisms underlying maintenance of ISCs and intestinal homeostasis.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Mucosa Intestinal/metabolismo , Proteínas Nucleares/metabolismo , Fatores de Transcrição SOX9/metabolismo , Células-Tronco/metabolismo , Animais , Células Epiteliais/metabolismo , Homeostase/fisiologia , Intestinos/fisiologia , Camundongos , Regiões Promotoras Genéticas/fisiologia , Fatores de Transcrição , Via de Sinalização Wnt/fisiologia
10.
Cancer Sci ; 112(9): 3669-3681, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34212455

RESUMO

Overcoming cisplatin (CDDP) resistance is a major issue in urothelial cancer (UC), in which CDDP-based chemotherapy is the first-line treatment. WEE1, a G2 /M checkpoint kinase, confers chemoresistance in response to genotoxic agents. However, the efficacy of WEE1 blockade in UC has not been reported. MK-1775, a WEE1 inhibitor also known as AZD-1775, blocked proliferation of UC cell lines in a dose-dependent manner irrespective of TP53 status. MK-1775 synergized with CDDP to block proliferation, inducing apoptosis and mitotic catastrophe in TP53-mutant UC cells but not in TP53-WT cells. Knocking down TP53 in TP53-WT cells induced synergism of MK-1775 and CDDP. In UMUC3 cell xenografts and two patient-derived xenograft lines with MDM2 overexpression, in which the p53/cell cycle pathway was inactivated, AZD-1775 combined with CDDP suppressed tumor growth inducing both M-phase entry and apoptosis, whereas AZD-1775 alone was as effective as the combination in RT4 cell xenografts. Drug susceptibility assay using an ex vivo cancer tissue-originated spheroid system showed correlations with the in vivo efficacy of AZD-1775 alone or combined with CDDP. We determined the feasibility of the drug susceptibility assay using spheroids established from UC surgical specimens obtained by transurethral resection. In conclusion, WEE1 is a promising therapeutic target in the treatment of UC, and a highly specific small molecule inhibitor is currently in early phase clinical trials for cancer. Differential antitumor efficacy of WEE1 blockade alone or combined with CDDP could exist according to p53/cell cycle pathway activity, which might be predictable using an ex vivo 3D primary culture system.


Assuntos
Antineoplásicos/administração & dosagem , Proteínas de Ciclo Celular/antagonistas & inibidores , Cisplatino/administração & dosagem , Inibidores Enzimáticos/administração & dosagem , Proteínas Tirosina Quinases/antagonistas & inibidores , Pirazóis/administração & dosagem , Pirimidinonas/administração & dosagem , Neoplasias da Bexiga Urinária/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Animais , Apoptose/efeitos dos fármacos , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , Técnicas de Silenciamento de Genes , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Camundongos SCID , Mitose/efeitos dos fármacos , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Transfecção , Resultado do Tratamento , Proteína Supressora de Tumor p53/deficiência , Proteína Supressora de Tumor p53/genética , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Gastroenterology ; 159(2): 682-696.e13, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32360551

RESUMO

BACKGROUND & AIMS: SETDB1, a histone methyltransferase that trimethylates histone H3 on lysine 9, promotes development of several tumor types. We investigated whether SETDB1 contributes to development of pancreatic ductal adenocarcinoma (PDAC). METHODS: We performed studies with Ptf1aCre; KrasG12D; Setdb1f/f, Ptf1aCre; KrasG12D; Trp53f/+; Setdb1f/f, and Ptf1aCre; KrasG12D; Trp53f/f; Setdb1f/f mice to investigate the effects of disruption of Setdb1 in mice with activated KRAS-induced pancreatic tumorigenesis, with heterozygous or homozygous disruption of Trp53. We performed microarray analyses of whole-pancreas tissues from Ptf1aCre; KrasG12D; Setdb1f/f, and Ptf1aCre; KrasG12D mice and compared their gene expression patterns. Chromatin immunoprecipitation assays were performed using acinar cells isolated from pancreata with and without disruption of Setdb1. We used human PDAC cells for SETDB1 knockdown and inhibitor experiments. RESULTS: Loss of SETDB1 from pancreas accelerated formation of premalignant lesions in mice with pancreata that express activated KRAS. Microarray analysis revealed up-regulated expression of genes in the apoptotic pathway and genes regulated by p53 in SETDB1-deficient pancreata. Deletion of Setdb1 from pancreas prevented formation of PDACs, concomitant with increased apoptosis and up-regulated expression of Trp53 in mice heterozygous for disruption of Trp53. In contrast, pancreata of mice with homozygous disruption of Trp53 had no increased apoptosis, and PDACs developed. Chromatin immunoprecipitation revealed that SETDB1 bound to the Trp53 promoter to regulate its expression. Expression of an inactivated form of SETDB1 in human PDAC cells with wild-type TP53 resulted in TP53-induced apoptosis. CONCLUSIONS: We found that the histone methyltransferase SETDB1 is required for development of PDACs, induced by activated KRAS, in mice. SETDB1 inhibits apoptosis by regulating expression of p53. SETDB1 might be a therapeutic target for PDACs that retain p53 function.


Assuntos
Apoptose , Carcinoma Ductal Pancreático/enzimologia , Transformação Celular Neoplásica/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Neoplasias Pancreáticas/enzimologia , Proteína Supressora de Tumor p53/metabolismo , Animais , Sítios de Ligação , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica , Histona-Lisina N-Metiltransferase/deficiência , Histona-Lisina N-Metiltransferase/genética , Humanos , Camundongos Knockout , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas p21(ras)/genética , Transdução de Sinais , Fatores de Transcrição/genética , Proteína Supressora de Tumor p53/deficiência , Proteína Supressora de Tumor p53/genética
12.
J Theor Biol ; 523: 110716, 2021 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-33862093

RESUMO

Cell signal transduction is an example of a nonequilibrium phenomenon. In this study, a nonequilibrium nonlinear thermodynamic model was formulated. First, we obtained a condition in which the Onsager's reciprocity theorem holds in the signal transduction. Second, it was found that the entropy production rate per signal molecule is conserved through signal transduction. Finally, it was determined that when Onsager's reciprocity theorem does not hold, fluctuation circulation is given by the phosphorylation rate of signal molecules. The simple relation implies that the fluctuation circulation can be an essential quantity of the signal transduction amount. These results expand the limit of nonequilibrium thermodynamics and can be used to provide ideas for signal transduction quantification.


Assuntos
Dinâmica não Linear , Transdução de Sinais , Entropia , Fosforilação , Termodinâmica
13.
J Immunol ; 202(11): 3161-3172, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-31019063

RESUMO

A defect in TCR-proximal signaling is a major characteristic of CD4 T cells in systemic lupus erythematosus; however, it is not fully known how defects in TCR signaling lead to lupus-like systemic autoimmunity characterized by germinal center development and autoantibody production against nuclear Ags. In this study, we show that SKG mice, which develop autoimmune arthritis in a BALB/c background due to defective TCR signaling by a Zap70 mutation, develop lupus-like systemic autoimmune disease in the C57BL/6 (B6) background (B6SKG mice). B6SKG mice showed multiorgan inflammation with immune complex deposition and anti-dsDNA Ab production. Follicular helper T cells (Tfh), which help germinal center formation, were spontaneously expanded in B6SKG mice. Th cells secreting IFN-γ or IL-17 and regulatory T cells were also increased in B6SKG mice compared with wild-type B6 mice, with the regulatory T cell subpopulation losing the expression of CD25. Among the factors related to Tfh differentiation, the number of dendritic cells and the expression levels of the costimulatory molecules CD80, CD86, and ICOSL in dendritic cells but not in B cells were specifically increased in wild-type B6 mice compared with BALB/c mice. The inhibition of these costimulatory molecules suppressed Tfh development and lupus-like autoimmunity. Thus, a defect in TCR-proximal signaling leads to lupus-like systemic autoimmunity under the specific genetic background that facilitates Tfh development.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Centro Germinativo/imunologia , Lúpus Eritematoso Sistêmico/genética , Mutação/genética , Proteína-Tirosina Quinase ZAP-70/genética , Animais , Anticorpos Antinucleares/metabolismo , Autoimunidade , Diferenciação Celular , Células Cultivadas , Citocinas/metabolismo , Humanos , Lúpus Eritematoso Sistêmico/imunologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptores de Antígenos de Linfócitos T/metabolismo
14.
Artigo em Inglês | MEDLINE | ID: mdl-30851107

RESUMO

OBJECTIVE: We aimed to clarify the clinical significance of serum levels of MMPs in interstitial lung disease (ILD) complicated with PM/DM (PM/DM-ILD). METHODS: We retrospectively analysed serum levels of seven subsets of MMPs in 52 PM/DM-ILD patients diagnosed at Kyoto University Hospital or Tenri Hospital from January 2005 to December 2014. The patients were sub-grouped based on the presence of anti-amimoacyl-tRNA synthetase antibody (anti-ARS antibody), anti-melanoma differentiation-associated protein 5 antibody (anti-MDA5 antibody) or lack of the antibodies (ARS-ILD, MDA5-ILD and other-ILD groups, respectively) and independently analysed. Eighteen PM/DM patients without ILD and 55 healthy control were also analysed. Associations between serum levels of MMPs and clinical findings including mortality were analysed. RESULTS: Among the MMPs analysed, MMP-7 serum levels in the ARS-ILD group were significantly higher compared with those in any of the other groups of PM/DM patients or in healthy controls. On the other hand, in the MDA5-ILD group, serum MMP-7 levels >5.08 ng/ml were associated with worse overall survival both in univariate (P = 0.017; odds ratio 18.0; 95% CI 1.69, 192.00) and multivariate (P = 0.027; odds ratio 14.60; 95% CI 1.11, 192.00) analyses. Immunohistochemical analysis suggested that MMP-7 was expressed in type II alveolar epithelial cells adjacent to the fibrotic lesions. CONCLUSION: Serum MMP-7 levels were higher in anti-ARS antibody-positive PM/DM-ILD patients, while higher serum MMP-7 levels among anti-MDA5 antibody-positive PM/DM-ILD patients were associated with a worse prognosis. Fibrotic processes may be associated with the elevation of serum MMP-7 levels.

15.
J Theor Biol ; 472: 84-87, 2019 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-30978350

RESUMO

Studies have reported that bio-cellular signal transduction can be investigated based on thermodynamics. This short article aims to consider signal transduction carried out by signaling molecules from the perspective of non-equilibrium thermodynamics. Under conditions in which total entropy production rate was minimized, the entropy production rate per signaling molecule was conserved independently of the steps during signal transduction. Accordingly, the conserved production rate can be defined as the channel capacity of the given signal transduction cascade. Non- equilibrium thermodynamics provides a theoretical framework for cell signal transduction.


Assuntos
Entropia , Modelos Biológicos , Transdução de Sinais , Espaço Intracelular/metabolismo , Fatores de Tempo
16.
Eur Surg Res ; 60(1-2): 63-73, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31055575

RESUMO

BACKGROUND: It was demonstrated that polyamines ameliorate ischemia-reperfusion injury (IRI) and promote regeneration in the liver. An optimal protocol of polyamine treatment remains unknown in the clinical setting. We examined 2 types of administration methods using rat models. METHODS: Experiment 1: evaluation of pharmacokinetics of polyamines. Experiment 2: for 3 days preoperatively and 5 days postoperatively, polyamines were given to male Lewis rats in the following three groups: the control group, no polyamine administration; the chow group, 0.05% polyamines mixed in chow; the bolus group, polyamines (200 µmol/kg) given by gastric tube once a day. All rats received 70% hepatectomy after 40 min of warm IRI. Postoperatively, IRI and regeneration were evaluated with assessment of serum levels of hepatic enzymes, histology and immunohistochemistry of liver tissue, and measurement of remnant liver weight. RESULTS: The blood concentrations of polyamines in the portal vein increased at 1 h of bolus administration, while they did not increase without the bolus. The bolus group was significantly associated with lower serum levels of aspartate/alanine aminotransferases (p < 0.05), decreased hepatocyte congestion, vacuolization and necrosis in histopathological scoring (p < 0.05), a lower number of TUNEL-positive hepatocytes (p < 0.05), higher remnant liver weight at 24, 48, and 168 h (p < 0.05), and a higher Ki-67 labeling index (24 h, p < 0.01) compared with the chow group. CONCLUSION: The bolus administration of polyamines was more effective in ameliorating IRI and promoting regeneration than chow administration. Perioperative bolus administration of polyamines might be an optimal treatment, when clinically applied.


Assuntos
Regeneração Hepática/efeitos dos fármacos , Fígado/irrigação sanguínea , Poliaminas/farmacologia , Traumatismo por Reperfusão/prevenção & controle , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Antígeno Ki-67/análise , Fígado/patologia , Masculino , Ratos , Ratos Endogâmicos Lew
17.
Liver Transpl ; 24(11): 1589-1602, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30120877

RESUMO

Cold storage (CS) remains the gold standard for organ preservation worldwide, although it is inevitably associated with ischemia/reperfusion injury (IRI). Molecular hydrogen (H2 ) is well known to have antioxidative properties. However, its unfavorable features, ie, inflammability, low solubility, and high tissue/substance permeability, have hampered its clinical application. To overcome such obstacles, we developed a novel reconditioning method for donor organs named hydrogen flush after cold storage (HyFACS), which is just an end-ischemic H2 flush directly to donor organs ex vivo, and, herein, we report its therapeutic impact against hepatic IRI. Whole liver grafts were retrieved from Wistar rats. After 24-hour CS in UW solution, livers were cold-flushed with H2 solution (1.0 ppm) via the portal vein (PV), the hepatic artery (HA), or both (PV + HA). Functional integrity and morphological damages were then evaluated by 2-hour oxygenated reperfusion at 37°C. HyFACS significantly lowered portal venous pressure, transaminase, and high mobility group box protein 1 release compared with vehicle-treated controls (P < 0.01). Hyaluronic acid clearance was significantly higher in the HyFACS-PV and -PV + HA groups when compared with the others (P < 0.01), demonstrating the efficacy of the PV route to maintain the sinusoidal endothelia. In contrast, bile production and lactate dehydrogenase leakage therein were both significantly improved in HyFACS-HA and -PV + HA (P < 0.01), representing the superiority of the arterial route to attenuate biliary damage. Electron microscopy consistently revealed that sinusoidal ultrastructures were well maintained by portal HyFACS, while microvilli in bile canaliculi were well preserved by arterial flush. As an underlying mechanism, HyFACS significantly lowered oxidative damages, thus improving the glutathione/glutathione disulfide ratio in liver tissue. In conclusion, HyFACS significantly protected liver grafts from IRI by ameliorating oxidative damage upon reperfusion in the characteristic manner with its route of administration. Given its safety, simplicity, and cost-effectiveness, end-ischemic HyFACS may be a novel pretransplant conditioning for cold-stored donor organs.


Assuntos
Antioxidantes/administração & dosagem , Hidrogênio/administração & dosagem , Preservação de Órgãos/métodos , Traumatismo por Reperfusão/prevenção & controle , Coleta de Tecidos e Órgãos/métodos , Aloenxertos/efeitos dos fármacos , Aloenxertos/patologia , Animais , Modelos Animais de Doenças , Humanos , Fígado/efeitos dos fármacos , Fígado/patologia , Transplante de Fígado , Masculino , Preservação de Órgãos/normas , Estresse Oxidativo/efeitos dos fármacos , Perfusão/instrumentação , Perfusão/métodos , Perfusão/normas , Ratos , Ratos Wistar , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/patologia , Coleta de Tecidos e Órgãos/efeitos adversos , Coleta de Tecidos e Órgãos/normas
18.
Entropy (Basel) ; 20(2)2018 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33265236

RESUMO

The analysis of cellular signaling cascades based on information thermodynamics has recently developed considerably. A signaling cascade may be considered a binary code system consisting of two types of signaling molecules that carry biological information, phosphorylated active, and non-phosphorylated inactive forms. This study aims to evaluate the signal transduction step in cascades from the viewpoint of changes in mixing entropy. An increase in active forms may induce biological signal transduction through a mixing entropy change, which induces a chemical potential current in the signaling cascade. We applied the fluctuation theorem to calculate the chemical potential current and found that the average entropy production current is independent of the step in the whole cascade. As a result, the entropy current carrying signal transduction is defined by the entropy current mobility.

19.
Entropy (Basel) ; 20(4)2018 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33265315

RESUMO

A cell signaling system is in a non-equilibrium state, and it includes multistep biochemical signaling cascades (BSCs), which involve phosphorylation of signaling molecules, such as mitogen-activated protein kinase (MAPK) pathways. In this study, the author considered signal transduction description using information thermodynamic theory. The ideal BSCs can be considered one type of the Szilard engine, and the presumed feedback controller, Maxwell's demon, can extract the work during signal transduction. In this model, the mutual entropy and chemical potential of the signal molecules can be redefined by the extracted chemical work in a mechanicochemical model, Szilard engine, of BSC. In conclusion, signal transduction is computable using the information thermodynamic method.

20.
Entropy (Basel) ; 20(4)2018 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33265394

RESUMO

Cell signal transduction is a non-equilibrium process characterized by the reaction cascade. This study aims to quantify and compare signal transduction cascades using a model of signal transduction. The signal duration was found to be linked to step-by-step transition probability, which was determined using information theory. By applying the fluctuation theorem for reversible signal steps, the transition probability was described using the average entropy production rate. Specifically, when the signal event number during the cascade was maximized, the average entropy production rate was found to be conserved during the entire cascade. This approach provides a quantitative means of analyzing signal transduction and identifies an effective cascade for a signaling network.

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