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1.
Gastroenterology ; 162(1): 223-237.e11, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34599932

RESUMO

BACKGROUND & AIMS: Throughout life, the intestinal epithelium undergoes constant self-renewal from intestinal stem cells. Together with genotoxic stressors and failing DNA repair, this self-renewal causes susceptibility toward malignant transformation. X-box binding protein 1 (XBP1) is a stress sensor involved in the unfolded protein response (UPR). We hypothesized that XBP1 acts as a signaling hub to regulate epithelial DNA damage responses. METHODS: Data from The Cancer Genome Atlas were analyzed for association of XBP1 with colorectal cancer (CRC) survival and molecular interactions between XBP1 and p53 pathway activity. The role of XBP1 in orchestrating p53-driven DNA damage response was tested in vitro in mouse models of chronic intestinal epithelial cell (IEC) DNA damage (Xbp1/H2bfl/fl, Xbp1ΔIEC, H2bΔIEC, H2b/Xbp1ΔIEC) and via orthotopic tumor organoid transplantation. Transcriptome analysis of intestinal organoids was performed to identify molecular targets of Xbp1-mediated DNA damage response. RESULTS: In The Cancer Genome Atlas data set of CRC, low XBP1 expression was significantly associated with poor overall survival and reduced p53 pathway activity. In vivo, H2b/Xbp1ΔIEC mice developed spontaneous intestinal carcinomas. Orthotopic tumor organoid transplantation revealed a metastatic potential of H2b/Xbp1ΔIEC-derived tumors. RNA sequencing of intestinal organoids (H2b/Xbp1fl/fl, H2bΔIEC, H2b/Xbp1ΔIEC, and H2b/p53ΔIEC) identified a transcriptional program downstream of p53, in which XBP1 directs DNA-damage-inducible transcript 4-like (Ddit4l) expression. DDIT4L inhibits mechanistic target of rapamycin-mediated phosphorylation of 4E-binding protein 1. Pharmacologic mechanistic target of rapamycin inhibition suppressed epithelial hyperproliferation via 4E-binding protein 1. CONCLUSIONS: Our data suggest a crucial role for XBP1 in coordinating epithelial DNA damage responses and stem cell function via a p53-DDIT4L-dependent feedback mechanism.


Assuntos
Adenocarcinoma/metabolismo , Adenoma/metabolismo , Transformação Celular Neoplásica/metabolismo , Dano ao DNA , Células Epiteliais/metabolismo , Mucosa Intestinal/metabolismo , Neoplasias Intestinais/metabolismo , Proteína 1 de Ligação a X-Box/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adenoma/tratamento farmacológico , Adenoma/genética , Adenoma/patologia , Animais , Proteínas de Ciclo Celular/metabolismo , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Bases de Dados Genéticas , Estresse do Retículo Endoplasmático , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Neoplasias Intestinais/tratamento farmacológico , Neoplasias Intestinais/genética , Neoplasias Intestinais/patologia , Inibidores de MTOR/farmacologia , Camundongos Knockout , Transdução de Sinais , Sirolimo/farmacologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteína 1 de Ligação a X-Box/genética
2.
Biochem Biophys Res Commun ; 628: 147-154, 2022 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-36087511

RESUMO

Expression of mucin MUC2, a component of the colonic mucus layer, plays a crucial role in intestinal homeostasis. Here, we describe a new regulator of MUC2 expression, the deubiquitinase ZRANB1 (Trabid). A ZRANB1 mutation changing cysteine to serine in amino acid position 443, affects ubiquitination. To analyze ZRANB1 function in the intestine, we generated Zranb1 C443S mutant knock-in (Zranb1C443S/C443S) mice using the CRISPR/Cas9 system. Zranb1C443S/C443S mice exhibited decreased mRNA expression and MUC2 production. Colonic organoids from Zranb1C443S/C443S mice displayed decreased Muc2 mRNA expression following differentiation into goblet cells. Finally, we analyzed dextran sulfate sodium-induced colitis to understand ZRANB1's role in intestinal inflammation. Zranb1C443S/C443S mice with colitis exhibited significant weight loss, reduced colon length, and worsening clinical and pathological scores, indicating that ZRANB1 contributes to intestinal homeostasis. Together, these results suggest that ZRANB1 regulates MUC2 expression and intestinal inflammation, which may help elucidating the pathogenesis of inflammatory bowel disease and developing new therapeutics targeting ZRANB1.


Assuntos
Colite , Mucosa Intestinal , Proteases Específicas de Ubiquitina , Animais , Colite/induzido quimicamente , Colite/genética , Colite/metabolismo , Cisteína/metabolismo , Enzimas Desubiquitinantes/metabolismo , Sulfato de Dextrana/toxicidade , Inflamação/patologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Camundongos , Mucinas/metabolismo , Muco/metabolismo , RNA Mensageiro/genética , Serina/metabolismo , Proteases Específicas de Ubiquitina/genética , Proteases Específicas de Ubiquitina/metabolismo
3.
Gut ; 2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33888516

RESUMO

OBJECTIVE: Haemorrhoidal disease (HEM) affects a large and silently suffering fraction of the population but its aetiology, including suspected genetic predisposition, is poorly understood. We report the first genome-wide association study (GWAS) meta-analysis to identify genetic risk factors for HEM to date. DESIGN: We conducted a GWAS meta-analysis of 218 920 patients with HEM and 725 213 controls of European ancestry. Using GWAS summary statistics, we performed multiple genetic correlation analyses between HEM and other traits as well as calculated HEM polygenic risk scores (PRS) and evaluated their translational potential in independent datasets. Using functional annotation of GWAS results, we identified HEM candidate genes, which differential expression and coexpression in HEM tissues were evaluated employing RNA-seq analyses. The localisation of expressed proteins at selected loci was investigated by immunohistochemistry. RESULTS: We demonstrate modest heritability and genetic correlation of HEM with several other diseases from the GI, neuroaffective and cardiovascular domains. HEM PRS validated in 180 435 individuals from independent datasets allowed the identification of those at risk and correlated with younger age of onset and recurrent surgery. We identified 102 independent HEM risk loci harbouring genes whose expression is enriched in blood vessels and GI tissues, and in pathways associated with smooth muscles, epithelial and endothelial development and morphogenesis. Network transcriptomic analyses highlighted HEM gene coexpression modules that are relevant to the development and integrity of the musculoskeletal and epidermal systems, and the organisation of the extracellular matrix. CONCLUSION: HEM has a genetic component that predisposes to smooth muscle, epithelial and connective tissue dysfunction.

4.
Gastroenterology ; 159(4): 1357-1374.e10, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32673694

RESUMO

BACKGROUND & AIMS: Excess and unresolved endoplasmic reticulum (ER) stress in intestinal epithelial cells (IECs) promotes intestinal inflammation. Activating transcription factor 6 (ATF6) is one of the signaling mediators of ER stress. We studied the pathways that regulate ATF6 and its role for inflammation in IECs. METHODS: We performed an RNA interference screen, using 23,349 unique small interfering RNAs targeting 7783 genes and a luciferase reporter controlled by an ATF6-dependent ERSE (ER stress-response element) promoter, to identify proteins that activate or inhibit the ATF6 signaling pathway in HEK293 cells. To validate the screening results, intestinal epithelial cell lines (Caco-2 cells) were transfected with small interfering RNAs or with a plasmid overexpressing a constitutively active form of ATF6. Caco-2 cells with a CRISPR-mediated disruption of autophagy related 16 like 1 gene (ATG16L1) were used to study the effect of ATF6 on ER stress in autophagy-deficient cells. We also studied intestinal organoids derived from mice that overexpress constitutively active ATF6, from mice with deletion of the autophagy related 16 like 1 or X-Box binding protein 1 gene in IECs (Atg16l1ΔIEC or Xbp1ΔIEC, which both develop spontaneous ileitis), from patients with Crohn's disease (CD) and healthy individuals (controls). Cells and organoids were incubated with tunicamycin to induce ER stress and/or chemical inhibitors of newly identified activator proteins of ATF6 signaling, and analyzed by real-time polymerase chain reaction and immunoblots. Atg16l1ΔIEC and control (Atg16l1fl/fl) mice were given intraperitoneal injections of tunicamycin and were treated with chemical inhibitors of ATF6 activating proteins. RESULTS: We identified and validated 15 suppressors and 7 activators of the ATF6 signaling pathway; activators included the regulatory subunit of casein kinase 2 (CSNK2B) and acyl-CoA synthetase long chain family member 1 (ACSL1). Knockdown or chemical inhibition of CSNK2B and ACSL1 in Caco-2 cells reduced activity of the ATF6-dependent ERSE reporter gene, diminished transcription of the ATF6 target genes HSP90B1 and HSPA5 and reduced NF-κB reporter gene activation on tunicamycin stimulation. Atg16l1ΔIEC and or Xbp1ΔIEC organoids showed increased expression of ATF6 and its target genes. Inhibitors of ACSL1 or CSNK2B prevented activation of ATF6 and reduced CXCL1 and tumor necrosis factor (TNF) expression in these organoids on induction of ER stress with tunicamycin. Injection of mice with inhibitors of ACSL1 or CSNK2B significantly reduced tunicamycin-mediated intestinal inflammation and IEC death and expression of CXCL1 and TNF in Atg16l1ΔIEC mice. Purified ileal IECs from patients with CD had higher levels of ATF6, CSNK2B, and HSPA5 messenger RNAs than controls; early-passage organoids from patients with active CD show increased levels of activated ATF6 protein, incubation of these organoids with inhibitors of ACSL1 or CSNK2B reduced transcription of ATF6 target genes, including TNF. CONCLUSIONS: Ileal IECs from patients with CD have higher levels of activated ATF6, which is regulated by CSNK2B and HSPA5. ATF6 increases expression of TNF and other inflammatory cytokines in response to ER stress in these cells and in organoids from Atg16l1ΔIEC and Xbp1ΔIEC mice. Strategies to inhibit the ATF6 signaling pathway might be developed for treatment of inflammatory bowel diseases.


Assuntos
Fator 6 Ativador da Transcrição/metabolismo , Estresse do Retículo Endoplasmático/fisiologia , Células Epiteliais/patologia , Íleo/metabolismo , Íleo/patologia , Doenças Inflamatórias Intestinais/metabolismo , Animais , Autofagia , Células CACO-2 , Técnicas de Cultura de Células , Chaperona BiP do Retículo Endoplasmático , Células HEK293 , Humanos , Doenças Inflamatórias Intestinais/etiologia , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/patologia , Camundongos , Transdução de Sinais
5.
Biochem Biophys Res Commun ; 542: 40-47, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33486190

RESUMO

Inflammatory bowel disease (IBD) comprises two major subtypes, ulcerative colitis (UC) and Crohn's disease, which are multifactorial diseases that may develop due to genetic susceptibility, dysbiosis, or environmental factors. Environmental triggers of IBD include food-borne factors, and a previous nationwide survey in Japan identified pre-illness consumption of isoflavones as a risk factor for UC. However, the precise mechanisms involved in the detrimental effects of isoflavones on the intestinal mucosa remain unclear. The present study employed human colonic organoids (hCOs) to investigate the functional effect of two representative isoflavones, genistein and daidzein, on human colonic epithelial cells. The addition of genistein to organoid reformation assays significantly decreased the number and size of reformed hCOs compared with control and daidzein treatment, indicating an inhibitory effect of genistein on colonic cell/progenitor cell function. Evaluation of the phosphorylation status of 49 different receptor tyrosine kinases showed that genistein selectively inhibited phosphorylation of epidermal growth factor receptor (EGFR) and hepatocyte growth factor receptor (HGFR). We established a two-dimensional wound-repair model using hCOs and showed that genistein significantly delayed the overall wound-repair response. Our results collectively show that genistein may exert its detrimental effects on the intestinal mucosa via negative regulation of stem/progenitor cell function, possibly leading to sustained mucosal injury and the development of UC.

6.
Gastroenterology ; 156(1): 145-159.e19, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30273559

RESUMO

BACKGROUND & AIMS: RNase H2 is a holoenzyme, composed of 3 subunits (ribonuclease H2 subunits A, B, and C), that cleaves RNA:DNA hybrids and removes mis-incorporated ribonucleotides from genomic DNA through ribonucleotide excision repair. Ribonucleotide incorporation by eukaryotic DNA polymerases occurs during every round of genome duplication and produces the most frequent type of naturally occurring DNA lesion. We investigated whether intestinal epithelial proliferation requires RNase H2 function and whether RNase H2 activity is disrupted during intestinal carcinogenesis. METHODS: We generated mice with epithelial-specific deletion of ribonuclease H2 subunit B (H2bΔIEC) and mice that also had deletion of tumor-suppressor protein p53 (H2b/p53ΔIEC); we compared phenotypes with those of littermate H2bfl/fl or H2b/p53fl/fl (control) mice at young and old ages. Intestinal tissues were collected and analyzed by histology. We isolated epithelial cells, generated intestinal organoids, and performed RNA sequence analyses. Mutation signatures of spontaneous tumors from H2b/p53ΔIEC mice were characterized by exome sequencing. We collected colorectal tumor specimens from 467 patients, measured levels of ribonuclease H2 subunit B, and associated these with patient survival times and transcriptome data. RESULTS: The H2bΔIEC mice had DNA damage to intestinal epithelial cells and proliferative exhaustion of the intestinal stem cell compartment compared with controls and H2b/p53ΔIEC mice. However, H2b/p53ΔIEC mice spontaneously developed small intestine and colon carcinomas. DNA from these tumors contained T>G base substitutions at GTG trinucleotides. Analyses of transcriptomes of human colorectal tumors associated lower levels of RNase H2 with shorter survival times. CONCLUSIONS: In analyses of mice with disruption of the ribonuclease H2 subunit B gene and colorectal tumors from patients, we provide evidence that RNase H2 functions as a colorectal tumor suppressor. H2b/p53ΔIEC mice can be used to study the roles of RNase H2 in tissue-specific carcinogenesis.


Assuntos
Transformação Celular Neoplásica/metabolismo , Células Epiteliais/enzimologia , Instabilidade Genômica , Neoplasias Intestinais/prevenção & controle , Intestino Delgado/enzimologia , Ribonuclease H/metabolismo , Animais , Proliferação de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Colite/induzido quimicamente , Colite/enzimologia , Colite/genética , Colite/patologia , Dano ao DNA , Sulfato de Dextrana , Modelos Animais de Doenças , Células Epiteliais/patologia , Feminino , Predisposição Genética para Doença , Humanos , Neoplasias Intestinais/enzimologia , Neoplasias Intestinais/genética , Neoplasias Intestinais/patologia , Intestino Delgado/patologia , Masculino , Camundongos Knockout , Fenótipo , Ribonuclease H/deficiência , Ribonuclease H/genética , Proteína Supressora de Tumor p53/deficiência , Proteína Supressora de Tumor p53/genética
7.
Exp Physiol ; 105(9): 1515-1523, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32700812

RESUMO

NEW FINDINGS: What is the central question of this study? What are the dynamic characteristics of cerebrovascular carbon dioxide reactivity and the central respiratory chemoreflex? What is the main finding and its importance? The transfer function gain from the end-tidal partial pressure of carbon dioxide to cerebral blood flow or ventilation decreased in the high frequency range at rest and during exercise. These findings indicate that the dynamic characteristics of both systems were not constant in all frequency ranges, and this trend was not modified by exercise. ABSTRACT: The purpose of this study was to examine the dynamic characteristics of cerebrovascular reactivity and ventilatory response to change in arterial CO2 in all frequency ranges at rest using frequency domain analysis, and also to examine whether this is modified by dynamic exercise as with the traditionally determined cerebrovascular CO2 reactivity. In nine healthy young subjects, at rest and during exercise (cycling exercise at constant predetermined work rate corresponding to a V̇O2 level of 0.90 l min-1 ), the dynamic characteristics of cerebrovascular CO2 reactivity and the central respiratory chemoreflex were assessed by transfer function analysis using a binary white-noise sequence (0-7% inspired CO2 fraction) from the end-tidal partial pressure of CO2 ( PETCO2 ) to the mean middle cerebral artery mean blood velocity (MCA Vm ) or minute ventilation ( V̇E ), respectively. In the high frequency range, both transfer function gains decreased but, interestingly, the cut-off frequency in the transfer function gain from PETCO2 to MCA Vm response was higher than that from PETCO2 to V̇E response at rest (0.024 vs. 0.015 Hz) and during exercise (0.030 vs. 0.011 Hz), indicating that cerebrovascular CO2 reactivity or central respiratory chemoreflex was not constant in all frequency ranges, and this trend was not modified by exercise. These findings suggest that dynamic characteristics of the cerebrovascular CO2 reactivity or central chemoreflex need to be assessed to identify the whole system because the traditional method cannot identify the property of time response of these systems.


Assuntos
Dióxido de Carbono/sangue , Circulação Cerebrovascular , Exercício Físico , Velocidade do Fluxo Sanguíneo , Humanos , Artéria Cerebral Média , Consumo de Oxigênio , Pressão Parcial , Adulto Jovem
8.
Exp Physiol ; 104(9): 1363-1370, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31264258

RESUMO

NEW FINDINGS: What is the central question of this study? There is an interaction between the regulatory systems of respiration and cerebral blood flow, because the mediator (CO2 ) is the same for both physiological systems. We examined whether the traditional method for determining cerebrovascular reactivity to CO2 is modified by changes in respiration. What is the main finding and its importance? Cerebrovascular reactivity was modified by voluntary changes in respiration during hypercapnia. This finding suggests that an alteration in the respiratory system may result in under- or overestimation of cerebrovascular reactivity determined by traditional methods in healthy adults. ABSTRACT: The cerebral vasculature is sensitive to changes in the arterial partial pressure of CO2 . This physiological mechanism has been well established as a cerebrovascular reactivity to CO2 (CVR). However, arterial CO2 may not be an independent variable in the traditional method for assessment of CVR, because the cerebral blood flow response is also affected by the activation of respiratory drive or higher centres in the brain. We hypothesized that CVR is modified by changes in respiration. To test our hypothesis, in the present study, 10 young, healthy subjects performed hyper- or hypoventilation to change end-tidal CO2 ( PET,CO2 ) with different concentrations of CO2 in the inhaled gas (0, 2.0 and 3.5%). We measured middle cerebral artery mean blood flow velocity by transcranial Doppler ultrasonography to identify the cerebral blood flow response to change in PET,CO2 during each set of conditions. In each set of conditions, PET,CO2 was significantly altered by changes in ventilation, and middle cerebral artery mean blood flow velocity changed accordingly. However, the relationship between changes in middle cerebral artery mean blood flow velocity and PET,CO2 as a response curve of CVR was reset upwards and downwards by hypo- and hyperventilation, respectively, compared with CVR during normal ventilation. The findings of the present study suggest the possibility that an alteration in respiration might lead to under- or overestimation of CVR determined by the traditional methods.


Assuntos
Dióxido de Carbono/metabolismo , Circulação Cerebrovascular/fisiologia , Artéria Cerebral Média/metabolismo , Artéria Cerebral Média/fisiopatologia , Adulto , Pressão Arterial/fisiologia , Velocidade do Fluxo Sanguíneo/fisiologia , Feminino , Humanos , Hipercapnia/metabolismo , Hipercapnia/fisiopatologia , Hiperventilação/metabolismo , Hiperventilação/fisiopatologia , Masculino , Pressão Parcial , Respiração , Ultrassonografia Doppler Transcraniana/métodos , Adulto Jovem
9.
Biochem Biophys Res Commun ; 482(4): 1296-1303, 2017 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-27939883

RESUMO

Ligand-dependent activation of Notch signaling is required to maintain the stem-cell niche of normal intestinal epithelium. However, the precise role of Notch signaling in the maintenance of the intestinal tumor stem cell niche and the importance of the RBPJ-independent non-canonical pathway in intestinal tumors remains unknown. Here we show that Notch signaling was activated in LGR5+ve cells of APC-deficient mice intestinal tumors. Accordingly, Notch ligands, including Jag1, Dll1, and Dll4, were expressed in these tumors. In vitro studies using tumor-derived organoids confirmed the intrinsic Notch activity-dependent growth of tumor cells. Surprisingly, the targeted deletion of Jag1 but not RBPJ in LGR5+ve tumor-initiating cells resulted in the silencing of Hes1 expression, disruption of the tumor stem cell niche, and dramatic reduction in the proliferation activity of APC-deficient intestinal tumors in vivo. Thus, our results highlight the importance of ligand-dependent non-canonical Notch signaling in the proliferation and maintenance of the tumor stem cell niche in APC-deficient intestinal adenomas.


Assuntos
Proteína da Polipose Adenomatosa do Colo/genética , Neoplasias Intestinais/metabolismo , Proteína Jagged-1/genética , Receptores Notch/metabolismo , Células-Tronco/citologia , Adenoma/metabolismo , Animais , Proliferação de Células , Fator de Crescimento Epidérmico/metabolismo , Deleção de Genes , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Ligantes , Camundongos , Microscopia de Fluorescência , Células-Tronco Neoplásicas/citologia , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais
10.
Biochem Biophys Res Commun ; 443(3): 840-6, 2014 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-24342613

RESUMO

Notch signaling plays an essential role in the proliferation and differentiation of intestinal epithelial cells (IECs). We have previously shown that Notch signaling is up-regulated in the inflamed mucosa of ulcerative colitis (UC) and thereby plays an indispensable role in tissue regeneration. Here we show that in addition to Notch signaling, STAT3 signaling is highly activated in the inflamed mucosa of UC. Forced expression of the Notch target gene Hes1 dramatically enhanced the IL-22-mediated STAT3-dependent transcription in human IECs. This enhancement of STAT3-dependent transcription was achieved by the extended phosphorylation of STAT3 by Hes1. Microarray analysis revealed that Hes1-mediated enhancement of IL-22-STAT3 signaling significantly increased the induction of genes encoding antimicrobial peptides, such as REG1A, REG3A and REG3G, in human IECs. Conversely, the reduction of Hes1 protein levels with a γ-secretase inhibitor significantly down-regulated the induction of those genes in IECs, resulting in a markedly poor response to IL-22. Our present findings identify a new role for the molecular function of Hes1 in which the protein can interact with cytokine signals and regulate the immune response of IECs.


Assuntos
Anti-Infecciosos/farmacologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Enterócitos/metabolismo , Proteínas de Homeodomínio/metabolismo , Interleucinas/farmacologia , Fator de Transcrição STAT3/metabolismo , Transcrição Gênica/efeitos dos fármacos , Antígenos de Neoplasias/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Linhagem Celular , Colite Ulcerativa/genética , Colite Ulcerativa/patologia , Enterócitos/efeitos dos fármacos , Enterócitos/patologia , Proteínas de Homeodomínio/genética , Humanos , Inflamação/patologia , Proteínas Associadas a Pancreatite , Fosforilação/efeitos dos fármacos , Receptores Notch/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fatores de Transcrição HES-1 , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética , Interleucina 22
11.
Front Physiol ; 15: 1227316, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38529482

RESUMO

Purpose: High-intensity interval training (HIIT) may induce training-specific physiological adaptations such as improved respiratory and cardiovascular adjustments before and after the onset of high-intensity exercise, leading to improved exercise performance during high-intensity exercise. The present study investigated the effects of HIIT on time-dependent cardiorespiratory adjustment during maximal exercise and before and after initiation of high-intensity exercise, as well as on maximal exercise performance. Methods: 21 healthy male college students were randomly assigned to HIIT group (n = 11) or control group (n = 10). HIIT group performed training on a cycle ergometer once a week for 8 weeks. The training consisted of three bouts of exercise at 95% maximal work rate (WRmax) until exhaustion. Before and after the HIIT program, dynamic cardiorespiratory function was investigated by ramp and step exercise tests, and HIIT-induced cardiac morphological changes were assessed using echocardiography. Results: HIIT significantly improved not only maximal oxygen uptake and minute ventilation, but also maximal heart rate (HR), systolic blood pressure (SBP), and time to exhaustion in both exercise tests (p < 0.05). Time-dependent increases in minute ventilation (VE) and HR before and at the start of exercise were significantly enhanced after HIIT. During high-intensity exercise, there was a strong correlation between percent change (from before to after HIIT program) in time to exhaustion and percent change in HRmax (r = 0.932, p < 0.001). Furthermore, HIIT-induced cardiac morphological changes such as ventricular wall hypertrophy was observed (p < 0.001). Conclusion: We have demonstrated that HIIT at 95% WRmax induces training-specific adaptations such as improved cardiorespiratory adjustments, not only during maximal exercise but also before and after the onset of high-intensity exercise, improvement of exercise performance mainly associated with circulatory systems.

12.
Gen Thorac Cardiovasc Surg ; 72(7): 455-465, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38180694

RESUMO

OBJECTIVES: To evaluate the influence of prolonged cardiopulmonary resuscitation (CPR) on outcomes in heart transplantation with higher risk donor hearts (HRDHs). METHODS: Patients transplanted in our hospital between May 2006 and December 2019 were divided into 2 groups, HRDH recipients and non HRDH recipients. HRDH was defined as meeting at least one of the following criteria: (1) donor left ventricular ejection fraction ≤ 50%, (2) donor-recipient predicted heart mass ratio < 0.8 or > 1.2, (3) donor age ≥ 55 years, (4) ischemic time > 4 h and (5) catecholamine index > 20. Recipients of HRDHs were divided into 3 groups according to the time of CPR (Group1: non-CPR, Group 2: less than 30 min-CPR, and Group 3: longer than 30 min CPR). RESULTS: A total of 125 recipients were enrolled in this study, composing of HRDH recipients (n = 97, 78%) and non HRDH recipients (n = 28, 22%). Overall survival and the rate of freedom from cardiac events at 10 years after heart transplantation were comparable between two groups. Of 97 HRDH recipients, 54 (56%) without CPR, 22 (23%) with CPR < 30 min, and 21 (22%) with CPR ≥ 30 min were identified. One-year survival rates were not significantly different among three groups. The 1-year rate of freedom from cardiac events was not also statistically different, excluding the patients with coronary artery disease found in early postoperative period, which was thought to be donor-transmitted disease. Multivariate logistics regression for cardiac events identified that the CPR duration was not a risk factor even in HRDH-recipients. CONCLUSION: The CPR duration did not affect the outcomes after heart transplantation in HRDH recipients.


Assuntos
Reanimação Cardiopulmonar , Transplante de Coração , Doadores de Tecidos , Humanos , Transplante de Coração/efeitos adversos , Masculino , Feminino , Pessoa de Meia-Idade , Fatores de Tempo , Adulto , Estudos Retrospectivos , Fatores de Risco , Medição de Risco , Resultado do Tratamento , Idoso
13.
Front Immunol ; 15: 1340048, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38327516

RESUMO

Recent advances in research suggest that aging has a controllable chronic inflammatory disease aspect. Aging systemic T cells, which secrete pro-inflammatory factors, affect surrounding somatic cells, and accelerate the aging process through chronic inflammation, have attracted attention as potential therapeutic targets in aging. On the other hand, there are few reports on the aging of the intestinal immune system, which differs from the systemic immune system in many ways. In the current study, we investigated the age-related changes in the intestinal immune system, particularly in T cells. The most significant changes were observed in the CD4+ T cells in the small intestinal IEL, with a marked increase in this fraction in old mice and reduced expression of CD27 and CD28, which are characteristic of aging systemic T cells. The proliferative capacity of aging IEL CD4+ T cells was significantly more reduced than that of aging systemic T cells. Transcriptome analysis showed that the expression of inflammatory cytokines was not upregulated, whereas Cd8α, NK receptors, and Granzymes were upregulated in aging IEL CD4+ T cells. Functional analysis showed that aging IEL T cells had a higher cytotoxic function against intestinal tumor organoids in vitro than young IEL T cells. scRNAseq revealed that splenic T cells show a transition from naïve to memory T cells, whereas intestinal T cells show the emergence of a CD8αα+CD4+ T cell fraction in aged mice, which is rarely seen in young cells. Further analysis of the aging IEL CD4+ T cells showed that two unique subsets are increased that are distinct from the systemic CD4+ T cells. Subset 1 has a pro-inflammatory component, with expression of IFNγ and upregulation of NFkB signaling pathways. Subset 2 does not express IFNγ, but upregulates inhibitory molecules and nIEL markers. Expression of granzymes and Cd8a was common to both. These fractions were in opposite positions in the clustering by UMAP and had different TCR repertoires. They may be involved in the suppression of intestinal aging and longevity through anti-tumor immunity, elimination of senescent cells and stressed cells in the aging environment. This finding could be a breakthrough in aging research.


Assuntos
Linfócitos Intraepiteliais , Camundongos , Animais , Linfócitos T CD4-Positivos , Granzimas , Subpopulações de Linfócitos T , Análise de Célula Única
14.
iScience ; 27(3): 109247, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38439969

RESUMO

In normal intestines, a fetal/regenerative/revival cell state can be induced upon inflammation. This plasticity in cell fate is also one of the current topics in human colorectal cancer (CRC). To dissect the underlying mechanisms, we generated human CRC organoids with naturally selected genetic mutation profiles and exposed them to two different conditions by modulating the extracellular matrix (ECM). Among tested mutation profiles, a fetal/regenerative/revival state was induced following YAP activation via a collagen type I-enriched microenvironment. Mechanistically, YAP transcription was promoted by activating AP-1 and TEAD-dependent transcription and suppressing intestinal lineage-determining transcription via mechanotransduction. The phenotypic conversion was also involved in chemoresistance, which could be potentially resolved by targeting the underlying YAP regulatory elements, a potential target of CRC treatment.

15.
iScience ; 27(3): 109173, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38496294

RESUMO

Inflammatory bowel diseases are characterized by the chronic relapsing inflammation of the gastrointestinal tract. While the molecular causality between endoplasmic reticulum (ER) stress and intestinal inflammation is widely accepted, the metabolic consequences of chronic ER stress on the pathophysiology of IBD remain unclear. By using in vitro, in vivo models, and patient datasets, we identified a distinct polarization of the mitochondrial one-carbon metabolism and a fine-tuning of the amino acid uptake in intestinal epithelial cells tailored to support GSH and NADPH metabolism upon ER stress. This metabolic phenotype strongly correlates with IBD severity and therapy response. Mechanistically, we uncover that both chronic ER stress and serine limitation disrupt cGAS-STING signaling, impairing the epithelial response against viral and bacterial infection and fueling experimental enteritis. Consequently, the antioxidant treatment restores STING function and virus control. Collectively, our data highlight the importance of serine metabolism to allow proper cGAS-STING signaling and innate immune responses upon gut inflammation.

16.
Psychogeriatrics ; 13(2): 118-23, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23909970

RESUMO

In Japan, indications for opioid analgesics, once exclusively used as pain killers for patients suffering from malignant cancer, have been expanded for a wide range of pain. Herein we report a patient with opioid-induced delirium associated with the administration of buprenorphine patches that was well below the indicated therapeutic range limit. An 82-year-old woman was referred to us from an orthopaedic practitioner for uncontrollable behavioural problems apparently caused by the beginning of dementia; the patient had gradually developed disorientation, visual hallucinations, and delusions. Laboratory and imaging findings excluded common causes of delirium including Alzheimer's disease and diffuse Lewy body disease. Detailed questioning revealed that the patient's confused state appeared following a buprenorphine patch dose increase and subsequently disappeared after administration was stopped. Delirium has not been reported as a side-effect in clinical trials of buprenorphine patches. However, our findings in this case show that even topical opioids can precipitate the development of a delirious state in elderly patients.


Assuntos
Analgésicos Opioides/efeitos adversos , Buprenorfina/efeitos adversos , Delírio/induzido quimicamente , Dor Lombar/tratamento farmacológico , Idoso de 80 Anos ou mais , Analgésicos Opioides/uso terapêutico , Confusão/induzido quimicamente , Delírio/complicações , Demência/tratamento farmacológico , Demência/psicologia , Feminino , Alucinações/complicações , Humanos , Japão , Adesivo Transdérmico , Resultado do Tratamento
17.
Acute Med Surg ; 10(1): e879, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37533436

RESUMO

Background: Splenic rupture because of metastasis from a distant organ is extremely rare. Case Presentation: An 80-year-old man presented with left flank pain. A computed tomography (CT) demonstrated a poorly enhanced enlarged spleen with bulky thrombus in the splenic vein without extravasations. A CT on the following day showed increased intraperitoneal hemorrhage; therefore, an emergency laparotomy was performed. The spleen was enlarged and ruptured with lacerations on its surface. Macroscopic examination showed congestion with a thrombus in the splenic vein around the hilum. Pathology revealed signet-ring cell carcinoma. On the third postoperative day, a massive cerebral infarction in the left middle cerebral artery was revealed. Endoscopic examination demonstrated normal gastric mucosa except for some erosions, for which biopsies were performed, and two of five specimens encompassed signet-ring cell carcinoma in the lamina propria. Conclusion: Occult cancer could result in a drastic manifestation of its metastasis accompanying systemic thrombotic events.

18.
J Gastroenterol ; 58(4): 379-393, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36745238

RESUMO

BACKGROUND: The organoids therapy for ulcerative colitis (UC) is under development. It is important to dissect how the engrafted epithelium can provide benefits for overcoming the vulnerability to inflammation. We mainly focused on the deliverability of sulfomucin, which is reported to play an important role in epithelial function. METHODS: We analyzed each segment of colon epithelium to determine differences in sulfomucin production in both mice and human. Subsequently, we transplanted organoids established from sulfomucin-enriched region into the injured recipient epithelium following dextran sulfate sodium-induced colitis and analyzed the engrafted epithelium in mouse model. RESULTS: In human normal colon, sulfomucin production was increased in proximal colon, whereas it was decreased in the inflammatory region of UC. In murine colon epithelium, increased sulfomucin production was found in cecum compared to distal small intestine and proximal colon. RNA sequencing analysis revealed that several key genes associated with sulfomucin production such as Papss2 and Slc26a1 were enriched in isolated murine cecum crypts. Then we established murine cecum organoids and transplanted them into the injured epithelium of distal colon. Although the expression of sulfomucin was temporally decreased in cecum organoids, its secretion was restored again in the engrafted patches after transplantation. Finally, we verified a part of mechanisms controlling sulfomucin production in human samples. CONCLUSION: This study illustrated the deliverability of sulfomucin in the disease-relevant grafting model to design sulfomucin-producing epithelial units in severely injured distal colon. The current study is the basis for the better promotion of organoids transplantation therapy for refractory UC.


Assuntos
Colite Ulcerativa , Colite , Humanos , Camundongos , Animais , Colite/induzido quimicamente , Colo/metabolismo , Colite Ulcerativa/terapia , Colite Ulcerativa/metabolismo , Organoides , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Mucosa Intestinal/metabolismo
19.
J Pediatr Surg ; 57(2): 224-228, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34903357

RESUMO

BACKGROUND: Retained intravascular catheter fragments (RICF) are a rare complication of implantable vascular access device (IVAD) removal for which there is limited understanding of aetiology. There is a varied approach to management among the currently published literature. AIMS: The aim of this study was to establish incidence, risk factors, and outcomes for RICF after attempted removal of IVADs. METHODS: A single institution retrospective review was undertaken of individuals ≤ 25 years undergoing removal of IVADs from October 2014 to June 2019. Risk factors for RICF were explored using univariable logistic and Cox regression analysis. RESULTS: Six cases of RICF were identified among 654 line removal episodes (0.92% (95% CI 0.37-2%)) in patients aged 6-17 years (median 11, IQR 6-15 years). The main risk factor for RICF at removal was found to be line duration (OR 3.5/year, 95% CI 2.1-5.84, p < 0.0001). No RICFs occurred in lines indwelling for < 3 years. Five children with RICF ≤ 16 years were discussed with a paediatric cardiothoracic centre, and all were left in situ with 4 remaining asymptomatic. One had the fragment tip extruded through a wound, which required trimming. The other (17 years of age) developed an infected sinus for which partial removal with open excision followed by full removal with endovascular snare retrieval was performed by the adult vascular surgeons. CONCLUSION: IVADs in-situ for longer than a three-year period are at greatest risk of RICF upon removal. Management with transfixion of line fragments to surrounding muscle seems prudent while invasive attempts at retrieval appear unwarranted.


Assuntos
Cateterismo Venoso Central , Dispositivos de Acesso Vascular , Adolescente , Adulto , Cateterismo Venoso Central/efeitos adversos , Cateteres de Demora/efeitos adversos , Criança , Remoção de Dispositivo , Humanos , Incidência , Estudos Retrospectivos , Fatores de Risco , Dispositivos de Acesso Vascular/efeitos adversos
20.
Physiol Rep ; 10(5): e15210, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35246949

RESUMO

This study aimed to investigate whether anticipatory cardiorespiratory responses vary depending on the intensity of the subsequent exercise bout, and whether anticipatory cardiorespiratory adjustments contribute importantly to enhancing exercise performance during high-intensity exercise. Eleven healthy men were provided advance notice of the exercise intensity and a countdown to generate anticipation during 10 min prior to exercise at 0, 50, 80 or 95% maximal work-rate (Experiment 1). A different group of subjects (n = 15) performed a time to exhaustion trial with or without anticipatory countdown (Experiment 2). In Experiment 1, heart rate (HR), oxygen uptake (VO2 ) and minute ventilation (VE ) during pre-exercise resting period increased over time and depended on the subsequent exercise intensity. Specifically, there was already a 7.4% increase in HR from more than 5 min prior to the start of exercise at 95% maximal work-rate, followed by progressively augmented increases of 12.5% between 2 and 3 min before exercise, 24.4% between 0 and 1 min before exercise. In Experiment 2, the initial HR for the first 10 s of exercise in the task with anticipation was 11.4% larger compared to without anticipation (p < 0.01), and the difference in HR between the two conditions decreased in a time-dependent manner. In contrast, the initial increases in VO2 and VE were significantly lower in the task with anticipation than that without anticipation. The time to exhaustion during high-intensity exercise was 14.6% longer under anticipation condition compared to no anticipation (135 ± 26 s vs. 119 ± 26 s, p = 0.003). In addition, the enhanced exercise performance correlated positively with increased HR response just before and immediately after exercise onset (p < 0.01). These results showed that anticipatory cardiorespiratory adjustments (feedforward control) via the higher brain that operate before starting exercise may play an important role in minimizing the time delay of circulatory response and enhancing performance after onset of high-intensity exercise in man.


Assuntos
Exercício Físico , Consumo de Oxigênio , Exercício Físico/fisiologia , Teste de Esforço , Frequência Cardíaca/fisiologia , Humanos , Masculino
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