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1.
N Engl J Med ; 385(5): 406-415, 2021 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-34133856

RESUMO

BACKGROUND: The efficacy and safety of tofacitinib, a Janus kinase inhibitor, in patients who are hospitalized with coronavirus disease 2019 (Covid-19) pneumonia are unclear. METHODS: We randomly assigned, in a 1:1 ratio, hospitalized adults with Covid-19 pneumonia to receive either tofacitinib at a dose of 10 mg or placebo twice daily for up to 14 days or until hospital discharge. The primary outcome was the occurrence of death or respiratory failure through day 28 as assessed with the use of an eight-level ordinal scale (with scores ranging from 1 to 8 and higher scores indicating a worse condition). All-cause mortality and safety were also assessed. RESULTS: A total of 289 patients underwent randomization at 15 sites in Brazil. Overall, 89.3% of the patients received glucocorticoids during hospitalization. The cumulative incidence of death or respiratory failure through day 28 was 18.1% in the tofacitinib group and 29.0% in the placebo group (risk ratio, 0.63; 95% confidence interval [CI], 0.41 to 0.97; P = 0.04). Death from any cause through day 28 occurred in 2.8% of the patients in the tofacitinib group and in 5.5% of those in the placebo group (hazard ratio, 0.49; 95% CI, 0.15 to 1.63). The proportional odds of having a worse score on the eight-level ordinal scale with tofacitinib, as compared with placebo, was 0.60 (95% CI, 0.36 to 1.00) at day 14 and 0.54 (95% CI, 0.27 to 1.06) at day 28. Serious adverse events occurred in 20 patients (14.1%) in the tofacitinib group and in 17 (12.0%) in the placebo group. CONCLUSIONS: Among patients hospitalized with Covid-19 pneumonia, tofacitinib led to a lower risk of death or respiratory failure through day 28 than placebo. (Funded by Pfizer; STOP-COVID ClinicalTrials.gov number, NCT04469114.).


Assuntos
Tratamento Farmacológico da COVID-19 , Glucocorticoides/uso terapêutico , Inibidores de Janus Quinases/uso terapêutico , Piperidinas/uso terapêutico , Pirimidinas/uso terapêutico , Adulto , Idoso , Antivirais/uso terapêutico , Brasil , COVID-19/complicações , COVID-19/mortalidade , COVID-19/terapia , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Hospitalização , Humanos , Incidência , Janus Quinase 3/antagonistas & inibidores , Inibidores de Janus Quinases/efeitos adversos , Masculino , Pessoa de Meia-Idade , Oxigenoterapia , Piperidinas/efeitos adversos , Pirimidinas/efeitos adversos , Insuficiência Respiratória/epidemiologia , Insuficiência Respiratória/etiologia
2.
Curr Ther Res Clin Exp ; 95: 100639, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34334801

RESUMO

BACKGROUND: Concerns have been raised that the risk of severe acute respiratory syndrome coronavirus 2 infection, or more severe or critical coronavirus disease 2019 (COVID-19), may be higher in immunocompromised individuals receiving immunomodulatory therapies compared with immunocompetent individuals. Tofacitinib is an oral Janus kinase inhibitor for the treatment of rheumatoid arthritis, psoriatic arthritis, ulcerative colitis, and polyarticular course juvenile idiopathic arthritis. To date, data on tofacitinib treatment during the COVID-19 pandemic are limited. OBJECTIVES: To summarize current understanding of the use of tofacitinib in adults during the COVID-19 pandemic, and discuss research questions that are yet to be addressed, to further inform the safe and effective use of tofacitinib in clinical practice. METHODS: We conducted a review of the literature (as of February 2021), to summarize the expert recommendations for the management of rheumatoid arthritis, psoriatic arthritis, and ulcerative colitis in the context of COVID-19, and to assess the current data regarding the use of tofacitinib in adult patients during the pandemic. RESULTS: Current recommendations for rheumatoid arthritis, psoriatic arthritis, and ulcerative colitis state that tofacitinib treatment should be continued during the pandemic, except in cases of positive or presumed severe acute respiratory syndrome coronavirus 2 infection. However, limited data are available; analyses of data from international rheumatology and gastroenterology registries have suggested that tofacitinib may not be associated with an increased risk of hospitalization or treatment switching in adults with COVID-19. CONCLUSIONS: Further assessment of tofacitinib use in patients with rheumatoid arthritis, psoriatic arthritis, or ulcerative colitis will be required to elucidate and establish the benefit:risk profile of tofacitinib during the current COVID-19 pandemic.

3.
Gut ; 63(7): 1081-91, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23964099

RESUMO

OBJECTIVE: Although genome wide association studies have partly uncovered the genetic basis of Crohn's disease (CD), it remains a challenge to link genetic polymorphisms to functional intestinal phenotypes. Paneth cells are specialised antimicrobial epithelial cells localised to the small-intestinal crypt-base. Here, we investigate whether genomic variations in ATG16L1 affect Paneth cell function. DESIGN: Genomic variation of ATG16L1 (T300A, rs2241880) was determined in DNA from 78 patients with CD and 12 healthy controls. Paraffin-embedded ileal biopsies from patients with genotype AA (n=17), GA (n=38) and patients with the GG allele (n=23) were stained for GRP78, phospho-EIF2α, lysozyme, cleaved-caspase 3, phosphohistone H3, phospho-IκB, p65, phospho-p38MAPK and PHLDA1. Microbial composition of biopsies was assessed by PCR. Disease phenotype was scored. RESULTS: In patients with quiescent disease but with an ATG16L1 risk allele, the endoplasmic reticulum (ER) stress markers GRP78 and pEIF2α were highly expressed in Paneth cells. Other CD risk gene variations did not correlate with Paneth cell ER stress. Functionally, patients with ER-stressed Paneth cells showed no changes in intestinal epithelial cells proliferation or apoptosis, Paneth cell or stem cell numbers, p65, phospho-IκB and phospho-p38 staining. However, a significantly increased presence of adherent-invasive Escherichia coli was observed in biopsies from patients with ER-stressed Paneth cells. Phenotypically, patients with GRP78 positive Paneth cells have relatively less colonic disease over ileal disease (-21%, p=0.04), more fistulas (+21%, p=0.05) and an increased need for intestinal surgery (+38%, p=0.002). CONCLUSIONS: The ATG16L1 T300A polymorphism defines a specific subtype of patients with CD, characterised by Paneth cell ER stress even during quiescent disease. Paneth cell ER stress correlates with bacterial persistence, and is thus likely to modulate antimicrobial functionality of this cell type in patients with CD.


Assuntos
Proteínas de Transporte/genética , Doença de Crohn/genética , Estresse do Retículo Endoplasmático/genética , Predisposição Genética para Doença , Celulas de Paneth/metabolismo , Polimorfismo de Nucleotídeo Único , Proteínas Relacionadas à Autofagia , Biópsia , Estudos de Casos e Controles , Células Cultivadas , Doença de Crohn/metabolismo , Doença de Crohn/microbiologia , Doença de Crohn/patologia , DNA Bacteriano/análise , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático/fisiologia , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Marcadores Genéticos , Técnicas de Genotipagem , Humanos , Íleo/metabolismo , Íleo/microbiologia , Íleo/patologia , Microbiota , Análise Multivariada , Celulas de Paneth/microbiologia , Celulas de Paneth/patologia , Fenótipo , Fatores de Risco
4.
Biochem J ; 441(1): 87-93, 2012 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-21864296

RESUMO

Xenotoxic damage in inflammatory diseases, including IBD (inflammatory bowel disease), is compounded by reduced activity of the xenobiotic transporter ABCG2 (ATP-binding-cassette G2) during the inflammatory state. An association between the activation of the unfolded protein response pathway and inflammation prompted us to investigate the possibility that reduced ABCG2 activity is causally linked to this response. To this end, we correlated expression of ABCG2 and the unfolded protein response marker GRP78 (glucose-regulated protein of 78 kDa) in colon biopsies from healthy individuals (n=9) and patients with inactive (n=67) or active (n=55) IBD, ischaemic colitis (n=10) or infectious colitis (n=14). In addition, tissue specimens throughout the small bowel from healthy individuals (n=27) and from patients with inactive (n=9) or active (n=25) Crohn's disease were co-stained for ABCG2 and GRP78. In all biopsies from patients with active inflammation, irrespective of the underlying disease, an absolute negative correlation was observed between epithelial ABCG2 expression and GRP78 expression, suggesting that inflammation-dependent activation of the unfolded protein response is responsible for suppression of ABCG2 function. The link between the unfolded protein response and functional ABCG2 expression was further corroborated by live imaging of ABCG2-expressing cells, which showed that various inflammatory mediators, including nitric oxide, activate the unfolded protein response and concomitantly reduce plasma membrane localization as well as transport function of ABCG2. Thus a novel mechanism for explaining xenobiotic stress during inflammation emerges in which intestinal inflammation activates the unfolded protein response, in turn abrogating defences against xenobiotic challenge by impairing ABCG2 expression and function.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Colite/metabolismo , Doença de Crohn/metabolismo , Regulação da Expressão Gênica/fisiologia , Mucosa Intestinal/metabolismo , Proteínas de Neoplasias/metabolismo , Dobramento de Proteína , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/genética , Colite/classificação , Chaperona BiP do Retículo Endoplasmático , Células Epiteliais/metabolismo , Células HEK293 , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Inflamação/metabolismo , Mucosa Intestinal/citologia , Mucosa Intestinal/patologia , Proteínas de Neoplasias/genética
5.
Adv Ther ; 40(10): 4440-4459, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37525075

RESUMO

INTRODUCTION: Tofacitinib is an oral small molecule Janus kinase inhibitor for the treatment of ulcerative colitis (UC). This post hoc analysis assessed whether various statistical techniques could predict outcomes of tofacitinib maintenance therapy in patients with UC. METHODS: Data from patients who participated in a 52-week, phase III maintenance study (OCTAVE Sustain) and an open-label long-term extension study (OCTAVE Open) were included in this analysis. Patients received tofacitinib 5 or 10 mg twice daily (BID) or placebo (OCTAVE Sustain only). Logistic regression analyses were performed to generate models using clinical and laboratory variables to predict loss of responder status at week 8 of OCTAVE Sustain, steroid-free remission (defined as a partial Mayo score of 0-1 in the absence of corticosteroid use) at week 52 of OCTAVE Sustain, and delayed response at week 8 of OCTAVE Open. Furthermore, differences in loss of response/discontinuation patterns between treatment groups in OCTAVE Sustain were established. RESULTS: The generated prediction models demonstrated insufficient accuracy for determining loss of response at week 8, steroid-free remission at week 52 in OCTAVE Sustain, or delayed response in OCTAVE Open. Both tofacitinib doses demonstrated comparable response/remission patterns based on visualizations of disease activity over time. The rectal bleeding subscore was the primary determinant of disease worsening (indicated by an increased total Mayo score), and the endoscopy subscore was the primary determinant of disease improvement (indicated by a decreased total Mayo score). CONCLUSION: Visualizations of disease activity subscores revealed distinct patterns among patients with UC that had disease worsening and disease improvement. The statistical models assessed in this analysis could not accurately predict loss of responder status, steroid-free remission, or delayed response to tofacitinib. Possible reasons include the small sample size or missing data related to yet unknown key variables that were not collected during these trials.


Doctors use tofacitinib (Xeljanz®) to treat people with moderate to severe ulcerative colitis. Patients who respond to (have improved symptoms following) treatment with tofacitinib 10 mg twice a day for 8 weeks, or up to 16 weeks if they do not respond initially (known as induction treatment), can receive tofacitinib treatment at the lowest effective dose to sustain their response (called maintenance treatment). Predicting how patients respond to tofacitinib maintenance treatment may help clinicians work out the lowest effective dose for each patient. In this study, data from the tofacitinib clinical trials were used to assess the ability to predict maintenance therapy response or failure in patients with ulcerative colitis. Differences between patients who received tofacitinib 5 or 10 mg twice a day and who either stopped responding to treatment or stopped taking treatment were looked at. The study could not accurately predict which patients would experience disease worsening, steroid-free remission (very mild or no symptoms, and not taking steroids), or take longer to respond following tofacitinib maintenance treatment. Patterns of patients who had stopped responding to treatment, or stopped taking treatment, were similar between patients who received tofacitinib 5 or 10 mg twice daily. When reviewed using doctor- and patient-reported scores that measure ulcerative colitis disease activity, different factors were important in patients with disease worsening compared with disease improvement. The results suggest that further research is needed to more accurately predict how patients with ulcerative colitis will respond to tofacitinib maintenance treatment.


Assuntos
Colite Ulcerativa , Inibidores de Janus Quinases , Humanos , Colite Ulcerativa/tratamento farmacológico , Inibidores de Janus Quinases/uso terapêutico , Indução de Remissão , Resultado do Tratamento , Ensaios Clínicos Fase III como Assunto
6.
Biochem Soc Trans ; 39(4): 1107-11, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21787357

RESUMO

The intestinal tract is covered by a total of 300 square metres of IECs (intestinal epithelial cells) that covers the entire intestinal mucosa. For protection against luminal xenobiotics, pathogens and commensal microbes, these IECs are equipped with membrane-bound transporters as well as the ability to secrete specific protective proteins. In patients with active IBD (inflammatory bowel disease), the expression of these proteins, e.g. ABC (ATP-binding cassette) transporters such as ABCG2 (ABC transporter G2) and defensins, is decreased, thereby limiting the protection against various luminal threats. Correct ER (endoplasmic reticulum)-dependent protein folding is essential for the localization and function of secreted and membrane-bound proteins. Inflammatory triggers, such as cytokines and nitric oxide, can impede protein folding, which causes the accumulation of unfolded proteins inside the ER. As a result, the unfolded protein response is activated which can lead to a cellular process named ER stress. The protein folding impairment affects the function and localization of several proteins, including those involved in protection against xenobiotics. In the present review, we discuss the possible inflammatory pathways affecting protein folding and eventually leading to IEC malfunction in patients with active IBD.


Assuntos
Doenças Inflamatórias Intestinais/metabolismo , Dobramento de Proteína , Animais , Colite/tratamento farmacológico , Colite/metabolismo , Colite/fisiopatologia , Retículo Endoplasmático/fisiologia , Células Epiteliais/metabolismo , Humanos , Mucosa Intestinal/patologia , Estresse Fisiológico , Resposta a Proteínas não Dobradas
7.
JGH Open ; 5(9): 1033-1040, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34584972

RESUMO

BACKGROUND AND AIM: The Global Ulcerative Colitis (UC) Narrative Survey aimed to evaluate the impact of UC, perceptions of UC burden, and management approaches. Here, we present data from patients and physicians in Australia. METHODS: Surveys, fielded by The Harris Poll, were completed by 215 patients with UC and 90 physicians, between August 2017 and February 2018. Surveys included questions on disease characteristics, impact on life, communication with physicians, and patient knowledge of UC. Results are presented descriptively from all respondents (with no imputation for missing data). RESULTS: Based on medication history, 84% of patients had moderate to severe UC. Diagnostic delay was on average 1.9 (SD 5.0) years and 48% of patients had waited ≥1 year for diagnosis. Nearly two-thirds (65%) of patients considered themselves to be in remission, with 97% also reporting a flare in the past year. The majority (92%) of patients were satisfied with their UC medication and, if their treatment made them feel "good enough," many (75%) would not consider an alternative. Most (90%) patients were satisfied with communication with their physician; however, only 48% felt comfortable raising emotional concerns. Both patients and physicians desired more time during routine appointments. Patients had gaps in their knowledge of UC, which physicians mostly recognized. CONCLUSIONS: The Australian survey results highlighted the diagnostic delay and burden of UC patients' experience, gaps in patients' knowledge of UC, and challenges in patient-physician communication. Compared with the overall Global UC Narrative Survey, patients in Australia reported a high burden of disease.

8.
Therap Adv Gastroenterol ; 14: 17562848211054710, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35154388

RESUMO

INTRODUCTION: Tofacitinib is an oral, small molecule Janus kinase inhibitor for the treatment of ulcerative colitis (UC). Outcome prediction based on early treatment response, along with clinical and laboratory variables, would be very useful for clinical practice. The aim of this study was to determine early variables predictive of responder status in patients with UC treated with tofacitinib. METHODS: Data were collected from patients treated with tofacitinib 10 mg twice daily in the OCTAVE Induction 1 and 2 studies (NCT01465763 and NCT01458951). Logistic regression and random forest analyses were performed to determine the power of clinical and/or laboratory variables to predict 2- and 3-point partial Mayo score responder status of patients at Weeks 4 or 8 after baseline. RESULTS: From a complete list of variables measured in OCTAVE Induction 1 and 2, analyses identified partial Mayo score, partial Mayo subscore (stool frequency, rectal bleeding, and Physician Global Assessment), cholesterol level, and C-reactive protein level as sufficient variables to predict responder status. Using these variables at baseline and Week 2 predicted responder status at Week 4 with 84-87% accuracy and Week 8 with 74-79% accuracy. Variables at baseline, Weeks 2 and 4 could predict responder status at Week 8 with 85-87% accuracy. CONCLUSION: Using a limited set of time-dependent variables, statistical and machine learning models enabled early and clinically meaningful predictions of tofacitinib treatment outcomes in patients with moderately to severely active UC.

9.
Inflamm Bowel Dis ; 27(11): 1747-1755, 2021 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-33529314

RESUMO

BACKGROUND: The Ulcerative Colitis (UC) Narrative is a global patient and physician survey aimed at identifying the impact of UC and comparing and contrasting perceptions of UC burden and management approaches. METHODS: Surveys of patients with UC (self-reported diagnosis; n = 2100) and physicians (n = 1254) were completed across 10 countries by The Harris Poll between August 2017 and February 2018. Questionnaires covered multiple aspects of UC, including diagnosis, treatment, and impact on patient quality of life, in addition to standard demographic information. Descriptive statistics are reported. RESULTS: The majority of patients (82%) had moderate to severe UC (based on medication history; those who had only ever taken 5-aminosalicylates were excluded); 67% described their UC as controlled with few to no symptoms. On average, patients experienced 4.3 flares (standard deviation, 7.4) in the past year. Diagnostic delay was on average 2.0 years (standard deviation, 5.4); 42% of patients waited ≥1 year. Most patients (65%) felt that UC controlled their life rather than them controlling their disease. Because of the fear of repercussions, many patients had not disclosed their UC to their employer. Discussion of the emotional impact of UC during routine appointments was less of a priority for physicians, compared with patients. CONCLUSIONS: The data from this global survey highlight that patients with UC experience diagnostic delay, poor disease control, and adverse impact on their quality of life. Patients report UC to be a mentally exhausting condition; however, emotional and mental health issues are infrequently discussed at routine appointments.


Assuntos
Colite Ulcerativa , Qualidade de Vida , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/terapia , Diagnóstico Tardio , Humanos , Saúde Mental , Relações Médico-Paciente , Médicos , Inquéritos e Questionários
10.
Inflamm Bowel Dis ; 27(7): 1096-1106, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33057598

RESUMO

BACKGROUND: The Ulcerative Colitis (UC) Narrative global surveys examined patient and physician perspectives on living with UC and tried to identify gaps in optimal care. Questions explored patient-physician interactions, UC management goals, and resources for improving communication. METHODS: Questionnaires were conducted across 10 countries, covering aspects of UC including diagnosis, treatment, and impact on patient quality of life, in addition to standard demographic information. Descriptive statistics were calculated. RESULTS: Globally, 2100 patients and 1254 physicians were surveyed (from August 2017 to February 2018). Results showed 85% of patients were satisfied with the communication they had with their physician, including discussions relating to symptoms (86%) and medication options (81%). However, 72% of patients wished for more information and support at initial diagnosis, and 48% did not feel comfortable talking to their physician about emotional concerns. Most patients (71%) set UC management goals with their physician. Both patients (63%) and physicians (79%) wished for longer appointments. Although 84% of physicians believed patient advocacy organizations to be important in UC management, more than half (54%) never discussed them with patients. CONCLUSIONS: These survey results highlight overall patient satisfaction with patient-physician communication but emphasize areas for improvement, such as patient desire to have more information earlier in their disease course. There is an unmet need for better information, materials, and support. Physicians need to consider which of the available tools and resources can help patients talk more openly, and accurately, because informed patients are more likely to engage with physicians in a shared decision-making process.


Assuntos
Colite Ulcerativa , Comunicação , Relações Médico-Paciente , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/terapia , Humanos , Satisfação do Paciente , Médicos , Qualidade de Vida , Inquéritos e Questionários
11.
PLoS One ; 14(10): e0221924, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31581194

RESUMO

BACKGROUND: The Pregnane X Receptor (PXR) is a principal signal transducer in mucosal responses to xenobiotic stress. It is well-recognized that inflammatory bowel disease is accompanied by xenobiotic stress, but the importance of the PXR in limiting inflammatory responses in inflammatory bowel disease remains obscure at best. METHODS: We stimulate a total of 106 colonic biopsies from 19 Crohn's disease patients with active disease, 36 colonic biopsies from 8 control patients, colonic organoids and various cell culture models (either proficient or genetically deficient with respect to PXR) in vitro with the PXR ligand rifampicin or vehicle. Effects on NF-κB activity are assessed by measuring interleukin-8 (IL-8) and interleukin-1ß (IL-1ß) mRNA levels by qPCR and in cell culture models by NF-κB reporter-driven luciferase activity and Western blot for signal transduction elements. RESULTS: We observe a strict inverse correlation between colonic epithelial PXR levels and NF-κB target gene expression in colonic biopsies from Crohn's disease patients. PXR, activated by rifampicin, is rate-limiting for mucosal NF-κB activation in IBD. The correlation between colonic epithelial PXR levels and NF-κB target gene expression was also observed in intestinal organoids system. Furthermore, in preclinical in vitro models of intestinal inflammation, including intestinal organoids, genetic inactivation of PXR unleashes NF-κB-dependent signal transduction whereas conversely NF-κB signaling reduces levels of PXR expression. CONCLUSIONS: Our data indicate that the PXR is a major and clinically relevant antagonist of NF-κB activity in the intestinal epithelial compartment during inflammatory bowel disease.


Assuntos
Doenças Inflamatórias Intestinais/metabolismo , Mucosa Intestinal/metabolismo , NF-kappa B/metabolismo , Receptor de Pregnano X/metabolismo , Biópsia , Linhagem Celular Tumoral , Citocinas/metabolismo , Humanos , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Rifampina/farmacologia , Transdução de Sinais/efeitos dos fármacos
12.
Sci Rep ; 4: 5468, 2014 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-24968806

RESUMO

Space flight strongly moderates human immunity but is in general well tolerated. Elucidation of the mechanisms by which zero gravity interacts with human immunity may provide clues for developing rational avenues to deal with exaggerated immune responses, e.g. as in autoimmune disease. Using two sounding rockets and one manned Soyuz launch, the influence of space flight on immunological signal transduction provoked by lipopolysaccharide (LPS) stimulation was investigated in freshly isolated peripheral blood monocytes and was compared to samples obtained from on-board centrifuge-loaded 1 g controls. The effect of microgravity on immunological signal transduction is highly specific, since LPS dependent Jun-N-terminal kinase activation is impaired in the 0 g condition, while the corresponding LPS dependent activation of p38 MAP kinase remains unaffected. Thus our results identify Jun-N-terminal kinase as a relevant target in immunity for microgravity and support using Jun-N-terminal kinase specific inhibitors for combating autoimmune disease.


Assuntos
Imunidade Inata/imunologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Monócitos/enzimologia , Voo Espacial , Estresse Fisiológico , Ausência de Peso , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Células Cultivadas , Humanos , Técnicas Imunoenzimáticas , Lipopolissacarídeos/farmacologia , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Transdução de Sinais/efeitos dos fármacos
13.
Sci Transl Med ; 6(233): 233ra53, 2014 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-24760188

RESUMO

In inflammatory bowel disease (IBD), large areas of apparently healthy mucosa lie adjacent to ulcerated intestine. Knowledge of the mechanisms that maintain remission in an otherwise inflamed intestine could provide important clues to the pathogenesis of this disease and provide rationale for clinical treatment strategies. We used kinome profiling to generate comprehensive descriptions of signal transduction pathways in inflamed and noninflamed colonic mucosa in a cohort of IBD patients, and compared the results to non-IBD controls. We observed that p21Rac1 guanosine triphosphatase (GTPase) signaling was strongly suppressed in noninflamed colonic mucosa in IBD. This suppression was due to both reduced guanine nucleotide exchange factor activity and increased intrinsic GTPase activity. Pharmacological p21Rac1 inhibition correlated with clinical improvement in IBD, and mechanistically unrelated pharmacological p21Rac1 inhibitors increased innate immune functions such as phagocytosis, bacterial killing, and interleukin-8 production in healthy controls and patients. Thus, suppression of p21Rac activity assists innate immunity in bactericidal activity and may induce remission in IBD.


Assuntos
Doença de Crohn/imunologia , Doença de Crohn/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Imunidade Inata , Transdução de Sinais , Proteínas rac1 de Ligação ao GTP/metabolismo , Animais , Biópsia , Doença de Crohn/patologia , Inibidor de Quinase Dependente de Ciclina p21/antagonistas & inibidores , Regulação para Baixo , Inibidores Enzimáticos/farmacologia , Proteínas Ativadoras de GTPase/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Guanosina Difosfato/metabolismo , Guanosina Trifosfato/metabolismo , Humanos , Hidrólise , Inflamação/patologia , Mucosa Intestinal/patologia , Proteínas Quinases/metabolismo , Indução de Remissão , Tioguanina/farmacologia , Proteínas rac1 de Ligação ao GTP/antagonistas & inibidores
14.
Int J Biochem Cell Biol ; 45(4): 798-806, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23291352

RESUMO

The epithelial layer of our intestines must meet two opposing requirements. On one hand it must allow for efficient uptake of nutrients and fluids, on the other hand it is a vital defence barrier between the milieu interior and the milieu exterior. In contrast to the lung that by virtue of cilia movement is kept virtually sterile, the gut epithelium is confronted by a stupendous microbiological load and a substantial xenobiotic challenge. The efficiency by which our intestinal epithelium manages to deal with the challenge of efficient nutrient absorption while simultaneously fulfilling its barrier function is testimony to what the forces of evolution can accomplish. Importantly, our understanding as to how our gut epithelial compartment manages this balancing act is now rapidly emerging, answering one of the oldest questions in cell biology. Importantly, when aberrations in this balance occur, for instance as a consequence genetic polymorphisms, increased propensity to develop chronic inflammation and inflammatory bowel disease is the result. Thus the knowledge on intestinal cell biology and biochemistry is not only of academic interest but may also aid design of novel avenues for the rational treatment of mucosal disease.


Assuntos
Biologia Celular , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/patologia , Animais , Meio Ambiente , Humanos , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/microbiologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Metagenoma
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