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1.
Cell ; 180(2): 278-295.e23, 2020 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-31978345

RESUMO

Mutations in FAMIN cause arthritis and inflammatory bowel disease in early childhood, and a common genetic variant increases the risk for Crohn's disease and leprosy. We developed an unbiased liquid chromatography-mass spectrometry screen for enzymatic activity of this orphan protein. We report that FAMIN phosphorolytically cleaves adenosine into adenine and ribose-1-phosphate. Such activity was considered absent from eukaryotic metabolism. FAMIN and its prokaryotic orthologs additionally have adenosine deaminase, purine nucleoside phosphorylase, and S-methyl-5'-thioadenosine phosphorylase activity, hence, combine activities of the namesake enzymes of central purine metabolism. FAMIN enables in macrophages a purine nucleotide cycle (PNC) between adenosine and inosine monophosphate and adenylosuccinate, which consumes aspartate and releases fumarate in a manner involving fatty acid oxidation and ATP-citrate lyase activity. This macrophage PNC synchronizes mitochondrial activity with glycolysis by balancing electron transfer to mitochondria, thereby supporting glycolytic activity and promoting oxidative phosphorylation and mitochondrial H+ and phosphate recycling.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Adenina/metabolismo , Adenosina/metabolismo , Adenosina Desaminase/metabolismo , Cromatografia Líquida/métodos , Células HEK293 , Células Hep G2 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Espectrometria de Massas/métodos , Enzimas Multifuncionais/genética , Fosforilação , Proteínas/genética , Nucleotídeos de Purina/metabolismo , Purinas/metabolismo
2.
Immunity ; 56(5): 1115-1131.e9, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-36917985

RESUMO

Intestinal IL-17-producing T helper (Th17) cells are dependent on adherent microbes in the gut for their development. However, how microbial adherence to intestinal epithelial cells (IECs) promotes Th17 cell differentiation remains enigmatic. Here, we found that Th17 cell-inducing gut bacteria generated an unfolded protein response (UPR) in IECs. Furthermore, subtilase cytotoxin expression or genetic removal of X-box binding protein 1 (Xbp1) in IECs caused a UPR and increased Th17 cells, even in antibiotic-treated or germ-free conditions. Mechanistically, UPR activation in IECs enhanced their production of both reactive oxygen species (ROS) and purine metabolites. Treating mice with N-acetyl-cysteine or allopurinol to reduce ROS production and xanthine, respectively, decreased Th17 cells that were associated with an elevated UPR. Th17-related genes also correlated with ER stress and the UPR in humans with inflammatory bowel disease. Overall, we identify a mechanism of intestinal Th17 cell differentiation that emerges from an IEC-associated UPR.


Assuntos
Estresse do Retículo Endoplasmático , Mucosa Intestinal , Células Th17 , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Células Th17/citologia , Células Th17/metabolismo , Diferenciação Celular , Humanos , Animais , Camundongos , Camundongos Transgênicos , Antibacterianos/farmacologia
4.
Radiology ; 307(3): e222389, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36853176

RESUMO

Background In Crohn disease, differentiation between active intestinal inflammation and fibrosis has implications for treatment, but current imaging modalities are not reliably accurate. Purpose To evaluate the predictive value of gallium 68 (68Ga)-labeled fibroblast activation protein inhibitor (FAPI) PET/MR enterography for the assessment of bowel wall fibrosis in Crohn disease. Materials and Methods In this prospective single-center study, consecutive participants with Crohn disease and obstructive symptoms underwent preoperative 68Ga-FAPI PET/MR enterography from May 2021 to January 2022. Histopathologic analysis of resected bowel segments was performed to grade active inflammation (A0-A2) and fibrosis (F0-F2), which served as the reference standard. The fibroblast activation protein (FAP) expression in bowel wall layers was analyzed immunohistochemically for each layer. 68Ga-FAPI-derived maximum standardized uptake value (SUVmax) was compared with histopathologic results by using mixed-model analysis of variance and Bonferroni-corrected post hoc tests. Results In 14 participants (mean age, 45 years ± 9 [SD]; 10 men), fibrosis was diagnosed histopathologically in 28 of 51 bowel segments (grade F1, n = 14; grade F2, n = 14). Mean SUVmax was higher in segments with fibrosis than without (7.6 vs 2.0; P < .001). In severe fibrosis, mean SUVmax was higher than in mild to moderate fibrosis (8.9 ± 0.9 vs 6.2 ± 0.9; P = .045). Bowel segments with isolated active inflammation had lower mean 68Ga-FAPI uptake than segments with combined active inflammation and fibrosis (SUVmax, 3.2 ± 0.4 vs 8.1 ± 0.1; P = .005). With an SUVmax cutoff value of 3.5, the area under the receiver operating characteristic curve for the prediction of fibrosis was 0.94 (95% CI: 0.9, 1.0), with sensitivity of 26 of 28 segments (93%) and specificity of five of six segments (83%). 68Ga-FAPI-derived SUVmax correlated with FAP expression across all bowel layers (R2 = 0.50, P < .001). Conclusion Higher gallium 68 fibroblast activation protein inhibitor uptake at PET/MR enterography was associated with histopathologically assessed bowel wall fibrosis in participants with Crohn disease, suggesting diagnostic potential for treatment decisions. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by O'Shea in this issue.


Assuntos
Doença de Crohn , Fibrose , Fibrose/diagnóstico por imagem , Doença de Crohn/patologia , Radioisótopos de Gálio , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons , Inflamação , Obstrução Intestinal/diagnóstico por imagem , Estudos Prospectivos , Compostos Radiofarmacêuticos , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso
5.
Am J Transplant ; 21(3): 968-977, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32633070

RESUMO

Eliminating cytoreductive conditioning from chimerism-based tolerance protocols would facilitate clinical translation. Here we investigated the impact of major histocompatibility complex (MHC) and minor histocompatibility antigen (MiHA) barriers on mechanisms of tolerance and rejection in this setting. Transient depletion of natural killer (NK) cells at the time of bone marrow (BM) transplantation (BMT) (20 × 106 BALB/c BM cells → C57BL/6 recipients under costimulation blockade [CB] and rapamycin) prevented BM rejection. Despite persistent levels of mixed chimerism, BMT recipients gradually rejected skin grafts from the same donor strain. Extending NK cell depletion did not improve skin graft survival. However, F1 (C57BL/6×BALB/c) donors, which do not elicit NK cell-mediated rejection, induced durable chimerism and tolerance. In contrast, if F1 donors with BALB/c background only were used (BALB/c×BALB.B), no tolerance was observed. In the absence of MiHA disparities (B10.D2 donors, MHC-mismatch only), temporal NK cell depletion established stable chimerism and tolerance. Conversely, MHC identical BM (BALB.B donors, MiHA mismatch only) readily engrafted without NK cell depletion but no skin graft tolerance ensued. Therefore, we conclude that under CB and rapamycin, MHC disparities provoke NK cell-mediated BM rejection in nonirradiated recipients whereas MiHA disparities do not prevent BM engraftment but impede skin graft tolerance in established mixed chimeras.


Assuntos
Quimerismo , Tolerância Imunológica , Animais , Transplante de Medula Óssea , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Transplante de Pele , Quimeras de Transplante , Tolerância ao Transplante
6.
Dig Dis Sci ; 65(9): 2712-2718, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31875288

RESUMO

BACKGROUND: The prognostic impact of liver steatosis in obese patients is well established. Limited data on the risk factors for and impact of hepatic steatosis in lean patients are available. AIMS: Assess risk factors for liver steatosis in lean patients and investigate its impact on survival. METHODS: Patients without viral hepatitis and with a BMI ≤ 25 kg/m2 undergoing liver stiffness measurement (LSM) and controlled attenuation parameter (CAP) by transient elastography were retrospectively identified. Clinical characteristics and laboratory test results were obtained at the time of LSM/CAP measurement. National death registry data were obtained in order to assess survival. RESULTS: Among n = 218 lean patients, n = 97 (34.5%) showed significant liver steatosis (CAP ≥ 268 dB/m), while n = 184 (65.5%) had no or just mild steatosis (CAP < 268 dB/m). Patients with steatosis had higher GGT (238.0(± 450.3) vs. 112.1(± 180.0) IU/mL; p = 0.013), AST (63(± 67.4) vs. 38.5(± 32.9) IU/mL; p = 0.001), ALT (59.1(± 58.8) vs. 44.3(± 52.7) IU/mL; p = 0.048) and triglyceride levels (120.1(± 80.3) vs. 96.1(± 58.2) mg/dL; p = 0.014), and showed a trend toward more severe fibrosis (LSM 15.6(± 19.5) vs. 12.0(± 15.7) kPa; p = 0.115). In multivariate binary logistic regression analysis, only serum uric acid levels were independently associated with liver steatosis (odds ratio 1.43 per unit mg/dL; 95% CI 1.001-2.054; p = 0.049). During a mean follow-up of 38.9(± 10.6) months, n = 14 patients (5.0%) died. In the absence of advanced fibrosis, survival after 1 year was similar in patients without (98.7%) and with (98.6%) significant steatosis. Patients with advanced fibrosis had worse 1-year survival without concomitant significant steatosis (84.8%) than patients with steatosis (95.8%; log-rank p < 0.001). CONCLUSIONS: High serum uric acid levels increase the risk of liver steatosis in lean patients. Liver fibrosis but not hepatic steatosis is a risk factor for impaired survival in lean patients.


Assuntos
Fígado Gorduroso/mortalidade , Cirrose Hepática/mortalidade , Magreza/mortalidade , Adulto , Índice de Massa Corporal , Técnicas de Imagem por Elasticidade , Fígado Gorduroso/diagnóstico por imagem , Feminino , Humanos , Hiperuricemia/sangue , Hiperuricemia/mortalidade , Cirrose Hepática/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Magreza/diagnóstico , Fatores de Tempo , Ácido Úrico/sangue
7.
Liver Int ; 39(1): 127-135, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30107095

RESUMO

BACKGROUND & AIMS: Assessment of hepatic steatosis by transient elastography (TE)-based controlled attenuation parameter (CAP) might predict hepatic decompensation. Therefore, we aimed to evaluate the prognostic value of CAP in patients with compensated advanced chronic liver disease (cACLD) and decompensated cirrhosis (DC). METHODS: A total of 430 patients who underwent TE (liver stiffness ≥10 kPa) and CAP measurements were included in this retrospective analysis. Half of patients (n = 189) underwent simultaneous HVPG measurement. In cACLD patients, first hepatic decompensation was defined by new onset of ascites, hepatic encephalopathy or variceal bleeding. In patients with DC, the following events were considered as further hepatic decompensation: requirement of paracentesis, admission for/development of grade 3/4 hepatic encephalopathy, variceal (re-)bleeding or liver-related death. RESULTS: First hepatic decompensation occurred in 25 of 292 (9%) cACLD patients, while 46 of 138 (33%) DC patients developed further hepatic decompensation during a median follow-up of 22 and 12 months respectively. CAP was not predictive of first (cACLD; per 10 dB/m; hazard ratio [HR]: 0.97, 95% confidence interval [95% CI]: 0.91-1.03, P = 0.321) or further hepatic decompensation (DC; HR: 0.99, 95% CI: 0.94-1.03, P = 0.554) in adjusted analysis. Using the well-established CAP cut-off of ≥248 dB/m for hepatic steatosis, the incidence of first (cACLD; P = 0.065) and further hepatic decompensation (DC; P = 0.578) was similar in patients with hepatic steatosis or without. Serum albumin levels (per mg/dL; HR: 0.83, 95% CI: 0.77-0.89, P < 0.001) and MELD-Na (per point; HR: 1.15, 95% CI: 1.04-1.28, P = 0.006) in cACLD and MELD-Na (per point; HR: 1.12, 95% CI: 1.05-1.19, P < 0.0001) in DC patients were the only parameters independently associated with first and further hepatic decompensation, respectively. CONCLUSION: Controlled attenuation parameter does not predict the development of first (cACLD)/further (DC) hepatic decompensation, while serum albumin levels and MELD-Na are of prognostic value.


Assuntos
Cirrose Hepática/complicações , Falência Hepática/diagnóstico , Fígado/diagnóstico por imagem , Adulto , Idoso , Técnicas de Imagem por Elasticidade , Feminino , Humanos , Falência Hepática/mortalidade , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Albumina Sérica Humana/análise
8.
Liver Transpl ; 24(1): 112-121, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28752925

RESUMO

Orthotopic liver transplantation (OLT) represents a curative treatment option for end-stage liver disease (ESLD). Although epidemiology of ESLD has recently changed due to the rising prevalence of nonalcoholic fatty liver disease and the decreased burden of hepatitis C virus infections due to highly effective antiviral regimens, the management of portal hypertension (PHT) remains a clinical challenge in the pre- and post-OLT setting. The measurement of the hepatic venous pressure gradient represents the most reliable but invasive tool for assessment of the severity of PHT. Although novel liver ultrasound and magnetic resonance-based elastography methods have been developed, their value to screen for liver fibrosis and PHT in transplanted patients remains to be established. Nonselective beta-blockers represent the cornerstone of medical treatment of PHT, but more studies on their effects on clinical endpoints after OLT are needed. Statins are widely used to treat hyperlipidemia, which is a common condition after OLT. Although a growing body of evidence suggests that statins decrease portal pressure and PHT-related complications in ESLD, studies on potential benefits of statins after OLT are lacking. Finally, transjugular intrahepatic portosystemic shunts (TIPS) are effective in decreasing PHT and seem to decrease mortality on the OLT waiting list. Moreover, TIPS does not have an impact on liver function nor complicate the transplant surgical procedures. TIPS may also be used after OLT, but the evidence is limited. In conclusion, whereas the management of PHT in patients with ESLD is based on strong evidence, further data on the value of noninvasive monitoring tools as well as on medical and invasive treatment options in the post-OLT setting are needed to improve management strategies in patients with recurrent PHT after liver transplantation. Liver Transplantation 24 112-121 2018 AASLD.


Assuntos
Doença Hepática Terminal/cirurgia , Hipertensão Portal/terapia , Transplante de Fígado/efeitos adversos , Antagonistas Adrenérgicos beta/uso terapêutico , Constrição Patológica/prevenção & controle , Doença Hepática Terminal/etiologia , Doença Hepática Terminal/mortalidade , Veias Hepáticas/cirurgia , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipertensão Portal/etiologia , Hipertensão Portal/mortalidade , Terapia de Imunossupressão/efeitos adversos , Terapia de Imunossupressão/métodos , Fígado/patologia , Fígado/cirurgia , Transplante de Fígado/métodos , Pressão na Veia Porta/efeitos dos fármacos , Veia Porta/efeitos dos fármacos , Veia Porta/fisiopatologia , Veia Porta/cirurgia , Derivação Portossistêmica Transjugular Intra-Hepática/métodos , Cuidados Pós-Operatórios/métodos , Guias de Prática Clínica como Assunto , Cuidados Pré-Operatórios/métodos , Índice de Gravidade de Doença , Transplantes/patologia , Transplantes/cirurgia
9.
Int Wound J ; 15(6): 914-920, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29956471

RESUMO

Hypertrophic scar formation because of surgical procedures is associated with higher levels of pain, a lower quality of life, and poor cosmetic outcome and requires more resources in follow-up management. An octenidine-based hydrogel has been shown to modulate immunological function in an in vitro wound model, suggesting an improved scar formation. In this prospective, randomised, observer-blinded, and intra-patient-controlled study, 45 patients who underwent abdominoplasty or mastectomy with transverse rectus abdominis muscle (TRAM) flap reconstruction were given both a standard postoperative wound dressing on one wound side and an octenidine-based hydrogel with transparent film dressing, covered with standard postoperative dressing on the other side. Four instances of hypertrophia were reported in the gel side versus 12 in the standard dressing side. Visual Analogue Scale (VAS) pain scores taken during postoperative dressing changes showed reduced scores on the gel side at all time points. Vancouver Scar Scale (VSS) scores showed improvement in the gel side at 3, 6, and 12 months postoperatively. Skin distensibility measured using a cutometer showed significantly improved measures in gel-treated wounds, similar to measures of healthy skin. Trans-epidermal water loss (TEWL), measured using a tewameter, showed improved values on the gel side soon after surgery, with both the control and the gel side normalising after approximately 6 months. The octenidine-based wound dressing demonstrates improved wound healing associated with a lower incidence of hypertrophic scar formation.


Assuntos
Abdominoplastia/métodos , Anti-Infecciosos/uso terapêutico , Cicatriz Hipertrófica/terapia , Hidrogéis/uso terapêutico , Curativos Oclusivos , Piridinas/uso terapêutico , Cicatrização/fisiologia , Adulto , Idoso , Feminino , Humanos , Iminas , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
11.
Clin Chim Acta ; 538: 53-59, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36375525

RESUMO

BACKGROUND AND AIMS: Systemic chemotherapy followed by hepatic resection is the treatment of choice for patients with colorectal cancer liver metastasis (CRCLM) but reliable biomarkers predicting response to therapy are needed. Spontaneous apoptosis of single tumour cells is common in CRCLM. We explored the potential of circulating apoptosis markers to predict treatment response. MATERIALS AND METHODS: Fifty-eight patients with CRCLM or hepatocellular carcinoma (HCC) were included in this study. Tumour tissue and blood samples were obtained before and after initiation of chemotherapy. Immunohistochemistry and ELISA assays were utilized to quantify the apoptosis marker caspase-cleaved cytokeratin 18 (M30) in tissue and circulation. RESULTS: CRCLM tissues showed more apoptotic tumour cells than HCC, or healthy liver. This was associated with elevated levels of circulating M30 (median = 244 U/l vs. 37 U/l in healthy controls, p = 0.009) which correlated with tumour volume (r2 = 0.92). Patients with progressive disease during chemotherapy showed higher M30 levels before therapy than responders (745 U/l vs. 136 U/l, p = 0.016). The predictive potential of M30 was higher than that of the tumour markers CA19-9 or CEA (AUC: 0.93, 0.63, and 0.78, respectively). CONCLUSIONS: Apoptotic tumour cells release cellular debris into the circulation, which provides information about tumour size and vitality.


Assuntos
Carcinoma Hepatocelular , Neoplasias Colorretais , Neoplasias Hepáticas , Humanos , Apoptose , Biomarcadores Tumorais , Caspases , Neoplasias Colorretais/tratamento farmacológico , Queratina-18 , Neoplasias Hepáticas/tratamento farmacológico , Carga Tumoral
12.
Int J Surg ; 109(12): 4113-4118, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37800585

RESUMO

INTRODUCTION: Surgical- and nonsurgical complications significantly worsen postoperative outcomes, and identification of patients at risk is crucial to improve care. This study investigated whether comorbidities, graded by the Charlson Comorbidity Index (CCI), impact complication rates and impair long-term outcome in a cohort of left-sided colorectal resections. METHODS: Retrospective analysis of patients undergoing oncological left-sided colorectal resections due to colorectal cancer between 01/2015 and 12/2020 in two referral centers in Austria using electronic medical records and national statistical bureau survival data. Patients with recurrent disease, peritoneal carcinomatosis, and emergency surgeries were excluded. Comorbidities were assessed using the CCI, and complication severity was defined by the Clavien-Dindo classification (CDC). Logistic regression analysis was performed to identify factors influencing the risk for postoperative complications, and overall survival was assessed using data from the national statistics bureau. RESULTS: A total of 471 patients were analyzed. Multinominal logistic regression analysis identified a CCI greater than or equal to 6 ( P =0.049; OR 1.59, 95% CI: 1.10-2.54) and male sex ( P =0.022; OR 1.47, 95% CI: 1.21-2.98) as independent risk factors for major complications. While patients with a high CCI had the worst postoperative survival rates, perioperative complications only impacted on overall survival in patients with low CCIs, but not in patients with high CCIs. CONCLUSION: Although a high CCI is a risk factor for major postoperative complications, the presence of comorbidities should not result in withholding surgery.


Assuntos
Neoplasias Colorretais , Complicações Pós-Operatórias , Humanos , Masculino , Estudos Retrospectivos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Comorbidade , Fatores de Risco , Neoplasias Colorretais/cirurgia , Neoplasias Colorretais/complicações
13.
Cell Mol Gastroenterol Hepatol ; 16(5): 847-856, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37572734

RESUMO

BACKGROUND & AIMS: Glucagon-like peptide (GLP)-2 may exert antifibrotic effects on hepatic stellate cells (HSCs). Thus, we aimed to test whether application of the GLP-2 analogue teduglutide has hepatoprotective and antifibrotic effects in the Mdr2/Abcb4-/- mouse model of sclerosing cholangitis displaying hepatic inflammation and fibrosis. METHODS: Mdr2-/- mice were injected daily for 4 weeks with teduglutide followed by gene expression profiling (bulk liver; isolated HSCs) and immunohistochemistry. Activated HSCs (LX2 cells) and immortalized human hepatocytes and human intestinal organoids were treated with GLP-2. mRNA profiling by reverse transcription polymerase chain reaction and electrophoretic mobility shift assay using cytosolic and nuclear protein extracts was performed. RESULTS: Hepatic inflammation, fibrosis, and reactive cholangiocyte phenotype were improved in GLP-2-treated Mdr2-/- mice. Primary HSCs isolated from Mdr2-/- mice and LX2 cells exposed to GLP-2 in vitro displayed significantly increased mRNA expression levels of NR4a1/Nur77 (P < .05). Electrophoretic mobility shift assay revealed an increased nuclear NR4a1 binding after GLP-2 treatment in LX2 cells. Moreover, GLP-2 alleviated the Tgfß-mediated reduction of NR4a1 nuclear binding activity. In vivo, GLP-2 treatment of Mdr2-/- mice resulted in increased intrahepatic levels of muricholic acids (accordingly Cyp2c70 mRNA expression was significantly increased), and in reduced mRNA levels of Cyp7a1 and FXR. Serum Fgf15 levels were increased in Mdr2-/- mice treated with GLP-2. Accordingly, GLP-2 treatment of human intestinal organoids activated their FXR-FGF19 signaling axis. CONCLUSIONS: GLP-2 treatment increased NR4a1/Nur77 activation in HSCs, subsequently attenuating their activation. GLP-2 promoted intestinal Fxr-Fgf15/19 signaling resulting in reduced Cyp7a1 and increased Cyp2c70 expression in the liver, contributing to hepatoprotective and antifibrotic effects of GLP-2 in the Mdr2-/- mouse model.


Assuntos
Células Estreladas do Fígado , Cirrose Hepática , Camundongos , Humanos , Animais , Células Estreladas do Fígado/metabolismo , Camundongos Knockout , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Modelos Animais de Doenças , RNA Mensageiro/metabolismo , Inflamação/metabolismo
14.
Front Immunol ; 13: 1060576, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36569922

RESUMO

Introduction: In de-novo kidney transplantation, the CTLA4-Ig fusion protein belatacept is associated with improved graft function but also an increased risk of acute rejection compared to calcineurin inhibitor therapy. The combination with a second costimulation blocker could potentially improve outcome while avoiding calcineurin inhibitor toxicity. The aim of this study was to define the conditions under which the combination of CTLA4-Ig and CD40L blockade leads to rejection-free permanent graft survival in a stringent murine heart transplantation model. Methods: Naïve wild-type or CD40L (CD154) knock-out mice received a fully mismatched BALB/c cardiac allograft. Selected induction and maintenance protocols for CTLA4-Ig and blocking αCD40L monoclonal antibodies (mAB) were investigated. Graft survival, rejection severity and donor-specific antibody (DSA) formation were assessed during a 100-day follow-up period. Results and Discussion: Administering αCD40L mAb as monotherapy at the time of transplantation significantly prolonged heart allograft survival but did not further improve the outcome when given in addition to chronic CTLA4-Ig therapy (which prolongs graft survival to a median of 22 days). Likewise, chronic αCD40L mAb therapy (0.5mg) combined with perioperative CTLA4-Ig led to rejection in a proportion of mice and extensive histological damage, despite abrogating DSA formation. Only the permanent interruption of CD40-CD40L signaling by using CD40L-/- recipient mice or by chronic αCD40L administration synergized with chronic CTLA4-Ig to achieve long-term allograft survival with preserved histological graft integrity in all recipients without DSA formation. The combination of α-CD40L and CTLA4-Ig works most effectively when both therapeutics are administered chronically.


Assuntos
Antígenos CD , Ligante de CD40 , Animais , Camundongos , Abatacepte/uso terapêutico , Inibidores de Calcineurina , Anticorpos Monoclonais/farmacologia , Aloenxertos
15.
Cell Metab ; 34(1): 106-124.e10, 2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34986329

RESUMO

Still's disease, the paradigm of autoinflammation-cum-autoimmunity, predisposes for a cytokine storm with excessive T lymphocyte activation upon viral infection. Loss of function of the purine nucleoside enzyme FAMIN is the sole known cause for monogenic Still's disease. Here we discovered that a FAMIN-enabled purine metabolon in dendritic cells (DCs) restrains CD4+ and CD8+ T cell priming. DCs with absent FAMIN activity prime for enhanced antigen-specific cytotoxicity, IFNγ secretion, and T cell expansion, resulting in excessive influenza A virus-specific responses. Enhanced priming is already manifest with hypomorphic FAMIN-I254V, for which ∼6% of mankind is homozygous. FAMIN controls membrane trafficking and restrains antigen presentation in an NADH/NAD+-dependent manner by balancing flux through adenine-guanine nucleotide interconversion cycles. FAMIN additionally converts hypoxanthine into inosine, which DCs release to dampen T cell activation. Compromised FAMIN consequently enhances immunosurveillance of syngeneic tumors. FAMIN is a biochemical checkpoint that protects against excessive antiviral T cell responses, autoimmunity, and autoinflammation.


Assuntos
Autoimunidade , Purinas , Linfócitos T CD8-Positivos , Células Dendríticas , Ativação Linfocitária , Purinas/metabolismo
16.
World J Hepatol ; 13(7): 731-746, 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34367495

RESUMO

Portal hypertension (PH), a common complication of liver cirrhosis, results in development of esophageal varices. When esophageal varices rupture, they cause significant upper gastrointestinal bleeding with mortality rates up to 20% despite state-of-the-art treatment. Thus, prophylactic measures are of utmost importance to improve outcomes of patients with PH. Several high-quality studies have demonstrated that non-selective beta blockers (NSBBs) or endoscopic band ligation (EBL) are effective for primary prophylaxis of variceal bleeding. In secondary prophylaxis, a combination of NSBB + EBL should be routinely used. Once esophageal varices develop and variceal bleeding occurs, standardized treatment algorithms should be followed to minimize bleeding-associated mortality. Special attention should be paid to avoidance of overtransfusion, early initiation of vasoconstrictive therapy, prophylactic antibiotics and early endoscopic therapy. Pre-emptive transjugular intrahepatic portosystemic shunt should be used in all Child C10-C13 patients experiencing variceal bleeding, and potentially in Child B patients with active bleeding at endoscopy. The use of carvedilol, safety of NSBBs in advanced cirrhosis (i.e. with refractory ascites) and assessment of hepatic venous pressure gradient response to NSBB is discussed. In the present review, we give an overview on the rationale behind the latest guidelines and summarize key papers that have led to significant advances in the field.

17.
World J Gastroenterol ; 27(19): 2281-2298, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34040322

RESUMO

The obesity pandemic has led to a significant increase in patients with metabolic dysfunction-associated fatty liver disease (MAFLD). While dyslipidemia, type 2 diabetes mellitus and cardiovascular diseases guide treatment in patients without signs of liver fibrosis, liver related morbidity and mortality becomes relevant for MAFLD's progressive form, non-alcoholic steatohepatitis (NASH), and upon development of liver fibrosis. Statins should be prescribed in patients without significant fibrosis despite concomitant liver diseases but are underutilized in the real-world setting. Bariatric surgery, especially Y-Roux bypass, has been proven to be superior to conservative and/or medical treatment for weight loss and resolution of obesity-associated diseases, but comes at a low but existent risk of surgical complications, reoperations and very rarely, paradoxical progression of NASH. Once end-stage liver disease develops, obese patients benefit from liver transplantation (LT), but may be at increased risk of perioperative infectious complications. After LT, metabolic comorbidities are commonly observed, irrespective of the underlying liver disease, but MAFLD/NASH patients are at even higher risk of disease recurrence. Few studies with low patient numbers evaluated if, and when, bariatric surgery may be an option to avoid disease recurrence but more high-quality studies are needed to establish clear recommendations. In this review, we summarize the most recent literature on treatment options for MAFLD and NASH and highlight important considerations to tailor therapy to individual patient's needs in light of their risk profile.


Assuntos
Cirurgia Bariátrica , Diabetes Mellitus Tipo 2 , Hepatopatia Gordurosa não Alcoólica , Obesidade Mórbida , Humanos , Cirrose Hepática/epidemiologia , Cirrose Hepática/terapia , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/terapia
18.
Wien Klin Wochenschr ; 131(17-18): 395-403, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31493100

RESUMO

BACKGROUND: Liver disease impacts on hepatic synthesis of lipoproteins and lipogenesis but data on dyslipidemia during disease progression are limited. We assessed the patterns of dyslipidemia in (i) different liver disease etiologies and discriminated (ii) non-advanced (non-ACLD) from advanced chronic liver disease (ACLD) as it is unclear how progression to ACLD impacts on dyslipidemia-associated cardiovascular risk. METHODS: Patients with alcoholic liver disease (n = 121), hepatitis C (n = 1438), hepatitis B (n = 384), metabolic/fatty liver disease (n = 532), cholestatic liver disease (n = 119), and autoimmune hepatitis (n = 114) were included. Liver stiffness ≥15 kPa defined ACLD. Dyslipidemia was defined as total cholesterol >200 mg/dL, low-density lipoprotein (LDL)-cholesterol >130 mg/dL and triglycerides >200 mg/dL. RESULTS: Across all etiologies, total cholesterol levels were significantly lower in ACLD, when compared to non-ACLD. Accordingly, LDL-cholesterol levels were significantly lower in ACLD due to hepatitis C, hepatitis B, metabolic/fatty liver disease and autoimmune hepatitis. Triglyceride levels did not differ due to disease severity in any etiology. Despite lower total and LDL cholesterol levels in ACLD, etiology-specific dyslipidemia patterns remained similar to non-ACLD. Contrary to this "improved" lipid status in ACLD, cardiovascular comorbidities were more prevalent in ACLD: arterial hypertension was present in 26.6% of non-ACLD and in 55.4% of ACLD patients (p < 0.001), and diabetes was present in 8.1% of non-ACLD and 25.6% of ACLD patients (p < 0.001). CONCLUSION: Liver disease etiology is a major determinant of dyslipidemia patterns and prevalence. Progression to ACLD "improves" serum lipid levels while arterial hypertension and diabetes mellitus are more prevalent. Future studies should evaluate cardiovascular events after ACLD-induced "improvement" of dyslipidemia.


Assuntos
Dislipidemias , Hepatopatias , Adulto , LDL-Colesterol/sangue , Dislipidemias/epidemiologia , Feminino , Humanos , Hepatopatias/epidemiologia , Hepatopatias/etiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Triglicerídeos/sangue
19.
Sci Rep ; 9(1): 11674, 2019 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-31406146

RESUMO

Statins reduce cardiovascular risk. However, "real-life" data on statin use in patients with chronic liver disease and its impact on overall and liver-related survival are limited. Therefore, we assessed 1265 CLD patients stratified as advanced (ACLD) or non-advanced (non-ACLD) stage. Statin indication was evaluated according to the 2013 ACC/AHA guidelines and survival-status was verified by national death registry data. Overall, 122 (9.6%) patients had an indication for statin therapy but did not receive statins, 178 (14.1%) patients were on statins and 965 (76.3%) patients had no indication for statins. Statin underutilization was 34.2% in non-ACLD and 48.2% in ACLD patients. In non-ACLD patients, survival was worse without a statin despite indication as compared to patients on statin or without indication (log-rank p = 0.018). In ACLD patients, statin use did not significantly impact on survival (log-rank p = 0.264). Multivariate cox regression analysis confirmed improved overall survival in patients with statin as compared to patients with indication but no statin (HR 0.225; 95%CI 0.053-0.959; p = 0.044) and a trend towards reduced liver-related mortality (HR 0.088; 95%CI 0.006-1.200; p = 0.068). This was not observed in ACLD patients. In conclusion, guideline-confirm statin use is often withhold from  patients with liver disease and this underutilization is associated with impaired survival in non-ACLD patients.


Assuntos
Anticolesterolemiantes/uso terapêutico , Dislipidemias/tratamento farmacológico , Insuficiência Hepática/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Adulto , Idoso , Doença Crônica , Dislipidemias/metabolismo , Dislipidemias/mortalidade , Dislipidemias/patologia , Feminino , Insuficiência Hepática/metabolismo , Insuficiência Hepática/mortalidade , Insuficiência Hepática/patologia , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Modelos de Riscos Proporcionais , Sistema de Registros
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