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1.
Nat Commun ; 15(1): 4528, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811532

RESUMO

Metabolic dysfunction-associated steatohepatitis (MASH) is the most prevalent cause of liver disease worldwide, with a single approved therapeutic. Previous research has shown that interleukin-22 (IL-22) can suppress ß-cell stress, reduce local islet inflammation, restore appropriate insulin production, reverse hyperglycemia, and ameliorate insulin resistance in preclinical models of diabetes. In clinical trials long-acting forms of IL-22 have led to increased proliferation in the skin and intestine, where the IL-22RA1 receptor is highly expressed. To maximise beneficial effects whilst reducing the risk of epithelial proliferation and cancer, we designed short-acting IL-22-bispecific biologic drugs that successfully targeted the liver and pancreas. Here we show 10-fold lower doses of these bispecific biologics exceed the beneficial effects of native IL-22 in multiple preclinical models of MASH, without off-target effects. Treatment restores glycemic control, markedly reduces hepatic steatosis, inflammation, and fibrogenesis. These short-acting IL-22-bispecific targeted biologics are a promising new therapeutic approach for MASH.


Assuntos
Fígado Gorduroso , Interleucina 22 , Interleucinas , Fígado , Pâncreas , Interleucinas/metabolismo , Animais , Fígado/metabolismo , Fígado/patologia , Fígado/efeitos dos fármacos , Pâncreas/patologia , Pâncreas/metabolismo , Pâncreas/efeitos dos fármacos , Humanos , Camundongos , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Resistência à Insulina , Receptores de Interleucina/metabolismo
2.
Autophagy ; 19(7): 1901-1915, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36740766

RESUMO

Guanine-quadruplex structures (G4) are unusual nucleic acid conformations formed by guanine-rich DNA and RNA sequences and known to control gene expression mechanisms, from transcription to protein synthesis. So far, a number of molecules that recognize G4 have been developed for potential therapeutic applications in human pathologies, including cancer and infectious diseases. These molecules are called G4 ligands. When the biological effects of G4 ligands are studied, the analysis is often limited to nucleic acid targets. However, recent evidence indicates that G4 ligands may target other cellular components and compartments such as lysosomes and mitochondria. Here, we summarize our current knowledge of the regulation of lysosome by G4 ligands, underlying their potential functional impact on lysosome biology and autophagic flux, as well as on the transcriptional regulation of lysosomal genes. We outline the consequences of these effects on cell fate decisions and we systematically analyzed G4-prone sequences within the promoter of 435 lysosome-related genes. Finally, we propose some hypotheses about the mechanisms involved in the regulation of lysosomes by G4 ligands.


Assuntos
Autofagia , Quadruplex G , Humanos , Ligantes , DNA/metabolismo , Guanina
3.
Environ Technol ; 44(11): 1600-1612, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34839790

RESUMO

Synthetic stormwater was tested to determine the ageing effects on dissolved metal concentrations and used in a column experiment to determine efficiency of four different filter materials (milkweed, bark, peat, polypropylene) in removing total and dissolved metals. Synthetic stormwater was created by adding metal salts, oil and collected stormwater sediment to tap water. Two ageing experiments were performed to determine the change of synthetic stormwater quality over time. One experiment lasted for 11 days and another focused on rapid concentration changes one day after preparation. The one-day ageing experiment showed rapid decrease in dissolved concentration of certain metals, specifically Cu. To consider this change, correction coefficients for each metal were developed and used to estimate the average dissolved metal concentration in the synthetic stormwater during the experiment to determine filter treatment efficiency. During the 11-day experiment on metal concentrations, no noticeable quality changes were observed for at least six days after the preparation of synthetic stormwater. Furthermore, a column experiment was run with duplicate filter columns. Inflow and outflow samples were analysed for total and dissolved metals, turbidity, particle size distribution, and pH. High removal of total metal concentrations was noticed in all tested filter media (58-94%). Dissolved metal concentration removal varied among different filter media. In general, columns with bark and peat media were able to treat dissolved metals better than polypropylene and milkweed. The level of treatment of dissolved metals between the different filter media columns were bark > peat > milkweed > polypropylene.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Purificação da Água , Polipropilenos , Metais , Solo , Sais , Poluentes Químicos da Água/análise , Chuva , Filtração , Metais Pesados/análise
4.
Int J Surg Protoc ; 26(1): 57-67, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35891921

RESUMO

Purpose: Overall complication and leak rates in colorectal surgery showed only minor improvements over the last years and remain still high. While the introduction of the WHO Safer Surgery Checklist has shown a reduction of overall operative mortality and morbidity in general surgery, only minor attempts have been made to improve outcomes by standardizing perioperative processes in colorectal surgery. Nevertheless, a number of singular interventions have been found reducing postoperative complications in colorectal surgery. The aim of the present study is to combine nine of these measures to a catalogue called colorectal bundle (CB). This will help to standardize pre-, intra-, and post-operative processes and therefore eventually reduce complication rates after colorectal surgery. Methods: The study will be performed among nine contributing hospitals in the extended north-western part of Switzerland. In the 6-month lasting control period the patients will be treated according to the local standard of each contributing hospital. After a short implementation phase all patients will be treated according to the CB for another 6 months. Afterwards complication rates before and after the implementation of the CB will be compared. Discussion: The overall complication rate in colorectal surgery is still high. The fact that only little progress has been made in recent years underlines the relevance of the current project. It has been shown for other areas of surgery that standardization is an effective measure of reducing postoperative complication rates. We hypothesize that the combination of effective, individual components into the CB can reduce the complication rate. Trial registration: Registered in ClinicalTrials.gov on 11/03/2020; NCT04550156. Highlights: Purpose: Overall complications in colorectal surgery remain still highStandardizing can reduce overall operative mortality and morbidityOnly minor attempts have been made to standardize perioperative processes in colorectal surgerySingular interventions have been found reducing postoperative complicationsThe aim is to combine nine of these measures to a colorectal bundle (CB)The CB will help to reduce complication rates after colorectal surgery Methods: The observational study will be performed among nine hospitals in SwitzerlandSix month the patients will be treated according to the local standardsAfterwards patients will be treated according to the CB for another six monthsComplication rates before and after the implementation of the CB will be compared Discussion: Only little progress has been made to reduce complication rate in colorectal surgeryStandardization is an effective measure of reducing complication ratesThe combination of effective, individual components into the CB can reduce the complication rate.

5.
Surgery ; 172(3): 975-981, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35623953

RESUMO

BACKGROUND: Although the correlation between tumor size and aggressiveness is clearly established in sporadic nonfunctional pancreatic neuroendocrine tumors, the management of tumors ≤2 cm remains debated. In recent guidelines, the cut-off size to operate ranged from 1 to 2 cm. The aim of this retrospective study was to report the rate of lymph nodes metastases in resected sporadic nonfunctional pancreatic neuroendocrine tumors, according to tumor size and, second, to identify risk factors of lymph node metastases and disease-free survival. METHODS: Resected sporadic nonfunctional pancreatic neuroendocrine tumors from 9 international expert centers were included (1999-2017). Functional pancreatic neuroendocrine tumors, genetic syndromes, and R2 resection were excluded. Aggressiveness was defined as microvascular invasion, perineural invasion, lymph node metastases, G3 grading, distant metastases, and/or recurrence. RESULTS: Overall, 495 resected sporadic nonfunctional pancreatic neuroendocrine tumors were included. For tumors up to 5 cm, the risk of lymph node metastases was increased by 1.73 for every 1 cm increase in size (odds ratio = 1.73; 95% confidence interval = 1.46-2.03). Tumor size >2 cm (P < .001), perineural invasion (P = .002), microvascular invasion (P < .001), and distant metastases (P = .008) were independently associated with lymph node metastases. Tumor size >2 cm (P = .003), R1 status (P = .004), lymph node metastases (P < .001), and World Health Organization grade 3 (P = .002) were independently associated with disease-free survival. Aggressiveness rate was 13.1% in tumors ≤1 cm and 29% in tumors between 1.1 and 2 cm. CONCLUSION: In resected sporadic nonfunctional pancreatic neuroendocrine tumors, the risk of lymph node metastases is correlated to tumor size. Considering that sporadic nonfunctional pancreatic neuroendocrine tumors between 1.1 and 2 cm had a higher risk of lymph node metastases and recurrence compared to tumors ≤1 cm, the decision to perform surgery in this subgroup of patients should be individualized in surgically fit patients.


Assuntos
Tumores Neuroendócrinos , Neoplasias Pancreáticas , Humanos , Metástase Linfática , Pancreatectomia , Estudos Retrospectivos
6.
Food Chem ; 389: 133092, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-35490513

RESUMO

Table salt fortified with KIO3 is commonly used to prevent iodine deficiency disorders. However, there is a lack of reliable data about the stability of KIO3 during food processing. In this study several meat and fish products were prepared with iodized salt and the iodine stability was determined through the whole production process. Applied processes included heating, fermenting, freezing, hot smoking, ripening by enzymes and storing. In all products an increase in iodine content was observed after addition of iodized salt. The iodine content remained constant during most of the applied processes. The only iodine loss was observed in ham after heating and can be explained by loss of iodine containing brine. During subsequent storage no iodine loss was observed in any of the products. The use of KIO3 fortified salt in the investigated products might therefore be beneficial for the iodine supply.


Assuntos
Iodo , Cloreto de Sódio na Dieta , Animais , Produtos Pesqueiros , Iodetos , Carne
7.
Mol Oncol ; 16(2): 527-537, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34653314

RESUMO

Circulating tumor DNA (ctDNA) has demonstrated great potential as a noninvasive biomarker to assess minimal residual disease (MRD) and profile tumor genotypes in patients with non-small-cell lung cancer (NSCLC). However, little is known about its dynamics during and after tumor resection, or its potential for predicting clinical outcomes. Here, we applied a targeted-capture high-throughput sequencing approach to profile ctDNA at various disease milestones and assessed its predictive value in patients with early-stage and locally advanced NSCLC. We prospectively enrolled 33 consecutive patients with stage IA to IIIB NSCLC undergoing curative-intent tumor resection (median follow-up: 26.2 months). From 21 patients, we serially collected 96 plasma samples before surgery, during surgery, 1-2 weeks postsurgery, and during follow-up. Deep next-generation sequencing using unique molecular identifiers was performed to identify and quantify tumor-specific mutations in ctDNA. Twelve patients (57%) had detectable mutations in ctDNA before tumor resection. Both ctDNA detection rates and ctDNA concentrations were significantly higher in plasma obtained during surgery compared with presurgical specimens (57% versus 19% ctDNA detection rate, and 12.47 versus 6.64 ng·mL-1 , respectively). Four patients (19%) remained ctDNA-positive at 1-2 weeks after surgery, with all of them (100%) experiencing disease progression at later time points. In contrast, only 4 out of 12 ctDNA-negative patients (33%) after surgery experienced relapse during follow-up. Positive ctDNA in early postoperative plasma samples was associated with shorter progression-free survival (P = 0.013) and overall survival (P = 0.004). Our findings suggest that, in early-stage and locally advanced NSCLC, intraoperative plasma sampling results in high ctDNA detection rates and that ctDNA positivity early after resection identifies patients at risk for relapse.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , DNA Tumoral Circulante/sangue , Neoplasias Pulmonares/patologia , Recidiva Local de Neoplasia/genética , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Mutação , Intervalo Livre de Progressão , Estudos Prospectivos
8.
Swiss Med Wkly ; 151: w30050, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34668688

RESUMO

AIM OF THE STUDY: To evaluate whether the outcome after open aneurysm repair combined with aorto-femoral bypass in patients with concomitant abdominal aortic aneurysm (AAA) and aorto-iliac occlusive disease (AIOD) is inferior to open aneurysm repair for isolated AAA or aorto-femoral bypass for isolated AIOD. METHODS: We performed a retrospective analysis of 30-day mortality, 1-year mortality and surgical complications of consecutive patients undergoing elective aneurysm repair, aorto-femoral bypass or a combination of these at two vascular surgery departments from 2003 to 2013. Potential risk factors were investigated by multivariable analysis. RESULTS: Overall, 511 patients underwent open repair for isolated AAA, 104 aorto-femoral bypass for isolated AIOD and 46 open AAA repair combined with aorto-femoral bypass for concomitant AAA and AIOD. Surgical complications occurred in 17% of AAA, 23% of AIOD and 37% of combined patients (odds ratio [OR] combined vs AAA 2.76, 95% confidence interval [CI] 1.43-5.34; p = 0.003). Colon ischaemia occurred in 3.7% of AAA, 2.9% of AIOD and 13% of combined patients (incicidence rate ratio [IRR] combined vs AAA 3.27, 95% CI 1.37-7.81; p = 0.01). The 30-day mortality was 3.1% in AAA, 4.8% in AIOD, and 11% in combined patients (IRR combined vs AAA 3.17, 95% CI 1.26-7.96; p = 0.01). One-year mortality was 5.7% in AAA, 5.8% in AIOD and 15% in combined patients (IRR combined vs AAA 2.50, 95% CI 1.17-5.35; p = 0.02). CONCLUSIONS: Combined AAA repair and aorto-femoral bypass has a significantly higher 30-day mortality and postoperative complication rate than isolated AAA repair. Patients with concomitant AAA and AIOD thus represent a high-risk population, which should be considered when deciding on the indication for AAA treatment.


Assuntos
Aneurisma da Aorta Abdominal , Arteriopatias Oclusivas , Aorta , Aneurisma da Aorta Abdominal/complicações , Aneurisma da Aorta Abdominal/cirurgia , Arteriopatias Oclusivas/complicações , Arteriopatias Oclusivas/cirurgia , Humanos , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
9.
Water Res ; 201: 117262, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34118650

RESUMO

Despite elaborate regulation of agricultural pesticides, their occurrence in non-target areas has been linked to adverse ecological effects on insects in several field investigations. Their quantitative role in contributing to the biodiversity crisis is, however, still not known. In a large-scale study across 101 sites of small lowland streams in Central Europe, Germany we revealed that 83% of agricultural streams did not meet the pesticide-related ecological targets. For the first time we identified that agricultural nonpoint-source pesticide pollution was the major driver in reducing vulnerable insect populations in aquatic invertebrate communities, exceeding the relevance of other anthropogenic stressors such as poor hydro-morphological structure and nutrients. We identified that the current authorisation of pesticides, which aims to prevent unacceptable adverse effects, underestimates the actual ecological risk as (i) measured pesticide concentrations exceeded current regulatory acceptable concentrations in 81% of the agricultural streams investigated, (ii) for several pesticides the inertia of the authorisation process impedes the incorporation of new scientific knowledge and (iii) existing thresholds of invertebrate toxicity drivers are not protective by a factor of 5.3 to 40. To provide adequate environmental quality objectives, the authorisation process needs to include monitoring-derived information on pesticide effects at the ecosystem level. Here, we derive such thresholds that ensure a protection of the invertebrate stream community.


Assuntos
Praguicidas , Poluentes Químicos da Água , Agricultura , Animais , Ecossistema , Monitoramento Ambiental , Europa (Continente) , Alemanha , Insetos , Invertebrados , Praguicidas/análise , Rios , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
10.
Nat Commun ; 12(1): 3543, 2021 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-34112803

RESUMO

Metastatic spread of a cancer to secondary sites is a coordinated, non-random process. Cancer cell-secreted vesicles, especially exosomes, have recently been implicated in the guidance of metastatic dissemination, with specific surface composition determining some aspects of organ-specific localization. Nevertheless, whether the tumor microenvironment influences exosome biodistribution has yet to be investigated. Here, we show that microenvironmental cytokines, particularly CCL2, decorate cancer exosomes via binding to surface glycosaminoglycan side chains of proteoglycans, causing exosome accumulation in specific cell subsets and organs. Exosome retention results in changes in the immune landscape within these organs, coupled with a higher metastatic burden. Strikingly, CCL2-decorated exosomes are directed to a subset of cells that express the CCL2 receptor CCR2, demonstrating that exosome-bound cytokines are a crucial determinant of exosome-cell interactions. In addition to the finding that cytokine-conjugated exosomes are detected in the blood of cancer patients, we discovered that healthy subjects derived exosomes are also associated with cytokines. Although displaying a different profile from exosomes isolated from cancer patients, it further indicates that specific combinations of cytokines bound to exosomes could likewise affect other physiological and disease settings.


Assuntos
Neoplasias da Mama/sangue , Quimiocina CCL2/metabolismo , Exossomos/metabolismo , Receptores CCR2/metabolismo , Microambiente Tumoral , Animais , Neoplasias da Mama/patologia , Citocinas/metabolismo , Exossomos/imunologia , Exossomos/patologia , Feminino , Glicosaminoglicanos/metabolismo , Humanos , Células Matadoras Naturais/imunologia , Fígado/imunologia , Fígado/metabolismo , Fígado/patologia , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/patologia , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Metástase Neoplásica , Proteoglicanas/metabolismo , Receptores de Citocinas/metabolismo , Baço/imunologia , Baço/metabolismo , Baço/patologia , Linfócitos T/imunologia , Microambiente Tumoral/imunologia
11.
Mol Cell Endocrinol ; 520: 111075, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33181235

RESUMO

Growth hormone (GH) actions via initiating cell signalling through the GH receptor (GHR) are important for many physiological processes, in addition to its well-known role in regulating growth. The activation of JAK-STAT signalling by GH is well characterized, however knowledge on GH activation of SRC family kinases (SFKs) is still limited. In this review we summarise the collective knowledge on the activation, regulation, and downstream signalling of GHR. We highlight studies on GH activation of SFKs and the important outcome of this signalling pathway with a focus on the different degradation mechanisms that can regulate GHR availability since this is an area that warrants further study considering its role in tumour progression.


Assuntos
Proteólise , Receptores da Somatotropina/metabolismo , Transdução de Sinais , Animais , Ativação Enzimática , Humanos , Modelos Biológicos , Receptores da Somatotropina/química , Quinases da Família src/metabolismo
12.
Cancers (Basel) ; 12(6)2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32570977

RESUMO

Lysosomes play a key role in regulating cell death in response to cancer therapies, yet little is known on the possible role of lysosomes in the therapeutic efficacy of G-quadruplex DNA ligands (G4L) in cancer cells. Here, we investigate the relationship between the modulation of lysosomal membrane damage and the degree to which cancer cells respond to the cytotoxic effects of G-quadruplex ligands belonging to the triarylpyridine family. Our results reveal that the lead compound of this family, 20A promotes the enlargement of the lysosome compartment as well as the induction of lysosome-relevant mRNAs. Interestingly, the combination of 20A and chloroquine (an inhibitor of lysosomal functions) led to a significant induction of lysosomal membrane permeabilization coupled to massive cell death. Similar effects were observed when chloroquine was added to three new triarylpyridine derivatives. Our findings thus uncover the lysosomal effects of triarylpyridines compounds and delineate a rationale for combining these compounds with chloroquine to increase their anticancer effects.

13.
Surg Endosc ; 34(12): 5469-5476, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-31993808

RESUMO

BACKGROUND: In bariatric surgery patients, pancreaticobiliary access via endoscopic retrograde cholangiopancreatography (ERCP) is technically challenging and the optimal approach for the evaluation and treatment of biliary tree-related pathologies has been debated. Besides laparoscopy-assisted ERCP (LA-ERCP) as standard of care, EUS-directed transgastric ERCP (EDGE) and hepaticogastrostomy (HGS) with placement of a fully covered metal stent have emerged as novel techniques. The objective of this study was to evaluate safety and efficacy of three different endoscopic approaches (LA-ERCP, EDGE, and HGS) in bariatric patients. METHODS: In this retrospective review, consecutive patients with Roux-en-Y gastric bypass (RYGB) and Sleeve Gastrectomy (SG) who underwent from 2013 to 2019 a LA-ERCP, an EDGE, or a HGS at a tertiary care reference center for bariatric surgery were analyzed. Patient demographics, type of procedure and indication, data regarding cannulation and therapeutic intervention of the common bile duct (procedure success), and clinical outcomes were analyzed. RESULTS: A total of 19 patients were included. Indications for LA-ERCP, EDGE, or HGS were mostly choledocholithiasis (78.9%) and in a few cases papillitis stenosans. Eight patients (57.1%) with LA-ERCP underwent concomitant cholecystectomy. Procedure success was achieved in 100%. Adverse events (AEs) were identified in 15.7% of patients (all ERCP related). All AEs were rated as moderate and there were no serious AEs. CONCLUSION: This case series indicates that ERCP via a transgastric approach (LA-ERCP, EDGE, or HGS) is a minimally invasive, effective, and feasible method to access the biliary tree in bariatric patients. These techniques offer an appealing alternative treatment option compared to percutaneous transhepatic cholangiography and drainage- or deep enteroscopy-assisted ERCP. In bariatric patients who earlier had a cholecystectomy, EUS-guided techniques were the preferred treatment options for biliary pathologies.


Assuntos
Procedimentos Cirúrgicos do Sistema Biliar/métodos , Derivação Gástrica/métodos , Atenção Terciária à Saúde/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
14.
Cell Death Dis ; 11(1): 8, 2020 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-31907357

RESUMO

The anti-apoptotic BCL-2 proteins (BCL-2, BCL-XL, MCL-1, A1, BCL-W) counteract apoptotic signals emerging during development and under stress conditions, and are thus essential for the survival of every cell. While the "BCL-2 addiction" of different cell types is well described in mouse models, there is only limited information available on the role of different anti-apoptotic BCL-2 proteins in a given human cell type. Here we characterize the role of BCL-XL for survival and function of human hematopoietic cells, with the aim to predict hematological side effects of novel BCL-XL-inhibiting BH3-mimetics and to identify hematological malignancies potentially responsive to such inhibitors. Earlier clinical studies have shown that the combined BCL-2/BCL-XL/BCL-W inhibitor, Navitoclax (ABT-263) induces severe thrombocytopenia caused by direct platelet demise and counteracted by increased megakaryopoiesis. In contrast, murine studies have reported important contribution of BCL-XL to survival of late erythroid cells and megakaryocytes. Using lentiviral knockdown, we show that the roles of BCL-XL for human hematopoietic cells are much more pronounced than expected from murine data and clinical trials. Efficient genetic or chemical BCL-XL inhibition resulted in significant loss of human erythroid cells beginning from very early stages of erythropoiesis, and in a reduction of megakaryocytes. Most importantly, BCL-XL deficient human hematopoietic stem cells and multipotent progenitors were reduced in numbers, and they showed a severely impaired capacity to engraft in mice during xenotransplantation. BCL-XL deficiency was fully compensated by BCL-2 overexpression, however, loss of its antagonist BIM did not result in any rescue of human erythroid or stem and progenitor cells. We thus conclude that novel and specific BCL-XL inhibitors might be efficient to treat malignancies of erythroid or megakaryocytic origin, such as polycythemia vera, acute erythroid leukemia, essential thrombocytosis or acute megakaryocytic leukemia. At the same time, it can be expected that they will have more severe hematological side effects than Navitoclax.


Assuntos
Eritropoese , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/metabolismo , Proteína bcl-X/metabolismo , Animais , Antígenos CD34/metabolismo , Proteína 11 Semelhante a Bcl-2/metabolismo , Benzotiazóis/farmacologia , Células Eritroides/efeitos dos fármacos , Células Eritroides/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Isoquinolinas/farmacologia , Camundongos , Transplante Heterólogo
15.
Elife ; 82019 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-31298656

RESUMO

Hypochlorous acid (HOCl), a powerful antimicrobial oxidant, is produced by neutrophils to fight infections. Here, we show that N-chlorination, induced by HOCl concentrations encountered at sites of inflammation, converts blood plasma proteins into chaperone-like holdases that protect other proteins from aggregation. This chaperone-like conversion was reversible by antioxidants and was abrogated by prior methylation of basic amino acids. Furthermore, reversible N-chlorination of basic amino acid side chains is the major factor that converts plasma proteins into efficient activators of immune cells. Finally, HOCl-modified serum albumin was found to act as a pro-survival molecule that protects neutrophils from cell death induced by highly immunogenic foreign antigens. We propose that activation and enhanced persistence of neutrophils mediated by HOCl-modified plasma proteins, resulting in the increased and prolonged generation of ROS, including HOCl, constitutes a potentially detrimental positive feedback loop that can only be attenuated through the reversible nature of the modification involved.


Assuntos
Proteínas Sanguíneas/farmacologia , Halogenação , Fatores Imunológicos/farmacologia , Aciltransferases/metabolismo , Antígenos de Bactérias/metabolismo , Antioxidantes/farmacologia , Proteínas de Bactérias/metabolismo , Linhagem Celular Tumoral , Cloraminas/análise , Humanos , Interações Hidrofóbicas e Hidrofílicas , Ácido Hipocloroso/farmacologia , Imunoglobulina G/metabolismo , Masculino , NADPH Oxidases/metabolismo , Ativação de Neutrófilo/efeitos dos fármacos , Oxirredução , Fosfatidilinositol 3-Quinases/metabolismo , Agregados Proteicos/efeitos dos fármacos , Explosão Respiratória/efeitos dos fármacos , Albumina Sérica/metabolismo , Transdução de Sinais/efeitos dos fármacos , Estaurosporina/farmacologia
16.
J R Soc Interface ; 16(155): 20180966, 2019 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-31213177

RESUMO

Non-equilibrium atmospheric-pressure plasmas are an alternative means to sterilize and disinfect. Plasma-mediated protein aggregation has been identified as one of the mechanisms responsible for the antibacterial features of plasma. Heat shock protein 33 (Hsp33) is a chaperone with holdase function that is activated when oxidative stress and unfolding conditions coincide. In its active form, it binds unfolded proteins and prevents their aggregation. Here we analyse the influence of plasma on the structure and function of Hsp33 of Escherichia coli using a dielectric barrier discharge plasma. While most other proteins studied so far were rapidly inactivated by atmospheric-pressure plasma, exposure to plasma activated Hsp33. Both, oxidation of cysteine residues and partial unfolding of Hsp33 were observed after plasma treatment. Plasma-mediated activation of Hsp33 was reversible by reducing agents, indicating that cysteine residues critical for regulation of Hsp33 activity were not irreversibly oxidized. However, the reduction yielded a protein that did not regain its original fold. Nevertheless, a second round of plasma treatment resulted again in a fully active protein that was unfolded to an even higher degree. These conformational states were not previously observed after chemical activation with HOCl. Thus, although we could detect the formation of HOCl in the liquid phase during plasma treatment, we conclude that other species must be involved in plasma activation of Hsp33. E. coli cells over-expressing the Hsp33-encoding gene hslO from a plasmid showed increased survival rates when treated with plasma while an hslO deletion mutant was hypersensitive emphasizing the importance of protein aggregation as an inactivation mechanism of plasma.


Assuntos
Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Escherichia coli/crescimento & desenvolvimento , Proteínas de Choque Térmico/química , Proteínas de Choque Térmico/metabolismo , Gases em Plasma/química , Agregados Proteicos , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas de Choque Térmico/genética , Oxirredução
17.
Foods ; 7(8)2018 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-30065167

RESUMO

Micronutrient deficiencies are a major public health problem. Beans are an important plant-based source of iron, zinc and copper, but their absorption is reduced in the presence of anti-nutrients such as phytates, polyphenols and tannins. Soaking and discarding the soaking water before cooking is unanimously recommended, but this can result in mineral loss. Data on the consequences for mineral bioaccessibility is still limited. This study aimed to evaluate iron, zinc and copper bioaccessibility in black beans cooked (regular pan, pressure cooker) with and without the soaking water. For that, three batches of black beans were investigated in triplicate, each split in nine parts (raw grains and four different household processes in duplicate) and analyzed by applying the quarter technique, resulting in a grand total of 164 samples. Minerals were quantified by ICP-MS (inductively coupled plasma mass spectrometry), myo-inositol phosphates (InsP5, InsP6) by HPLC (high-performance liquid chromatography) ion-pair chromatography, total polyphenols using Folin-Denis reagent and condensed tannins using Vanillin assay. Mineral bioaccessibility was determined by in vitro digestion and dialysis. All treatments resulted in a statistically significant reduction of total polyphenols (30%) and condensed tannins (20%). Only when discarding the soaking water a loss of iron (6%) and copper (30%) was observed, and InsP6 was slightly decreased (7%) in one treatment. The bioaccessibility of iron and zinc were low (about 0.2% iron and 35% zinc), but copper presented high bioaccessibility (about 70%). Cooking beans under pressure without discarding the soaking water resulted in the highest bioaccessibility levels among all household procedures. Discarding the soaking water before cooking did not improve the nutritional quality of the beans.

18.
Front Immunol ; 9: 871, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29867925

RESUMO

Tumor-derived exosomes are being recognized as essential mediators of intercellular communication between cancer and immune cells. It is well established that bone marrow-derived macrophages (BMDMs) take up tumor-derived exosomes. However, the functional impact of these exosomes on macrophage phenotypes is controversial and not well studied. Here, we show that breast cancer-derived exosomes alter the phenotype of macrophages through the interleukin-6 (IL-6) receptor beta (glycoprotein 130, gp130)-STAT3 signaling pathway. Addition of breast cancer-derived exosomes to macrophages results in the activation of the IL-6 response pathway, including phosphorylation of the key downstream transcription factor STAT3. Exosomal gp130, which is highly enriched in cancer exosomes, triggers the secretion of IL-6 from BMDMs. Moreover, the exposure of BMDMs to cancer-derived exosomes triggers changes from a conventional toward a polarized phenotype often observed in tumor-associated macrophages. All of these effects can be inhibited through the addition of a gp130 inhibitor to cancer-derived exosomes or by blocking BMDMs exosome uptake. Collectively, this work demonstrates that breast cancer-derived exosomes are capable of inducing IL-6 secretion and a pro-survival phenotype in macrophages, partially via gp130/STAT3 signaling.


Assuntos
Exossomos/imunologia , Macrófagos/imunologia , Neoplasias Mamárias Experimentais/imunologia , Transdução de Sinais/imunologia , Microambiente Tumoral/imunologia , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Técnicas de Cocultura , Receptor gp130 de Citocina/antagonistas & inibidores , Receptor gp130 de Citocina/imunologia , Receptor gp130 de Citocina/metabolismo , Exossomos/efeitos dos fármacos , Exossomos/metabolismo , Feminino , Hidrazinas/farmacologia , Interleucina-6/imunologia , Interleucina-6/metabolismo , Ativação de Macrófagos/efeitos dos fármacos , Ativação de Macrófagos/imunologia , Macrófagos/citologia , Macrófagos/metabolismo , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Cultura Primária de Células , Quinoxalinas/farmacologia , Fator de Transcrição STAT3/imunologia , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos
19.
Free Radic Biol Med ; 106: 329-338, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28242229

RESUMO

The genetically encoded probes roGFP2-Orp1 and Grx1-roGFP2 have been designed to be selectively oxidized by hydrogen peroxide (H2O2) and glutathione disulfide (GSSG), respectively. Both probes have demonstrated such selectivity in a broad variety of systems and conditions. In this study, we systematically compared the in vitro response of roGFP2, roGFP2-Orp1 and Grx1-roGFP2 to increasing amounts of various oxidant species that may also occur in biological settings. We conclude that the previously established oxidant selectivity is highly robust and likely to be maintained under most physiological conditions. Yet, we also find that hypochlorous acid, known to be produced in the phagocyte respiratory burst, can lead to non-selective oxidation of roGFP2-based probes at concentrations ≥2µM, in vitro. Further, we confirm that polysulfides trigger direct roGFP2 responses. A side-by-side comparison of all three probes can be used to reveal micromolar amounts of hypochlorous acid or polysulfides.


Assuntos
Dissulfeto de Glutationa/química , Proteínas de Fluorescência Verde/genética , Peróxido de Hidrogênio/isolamento & purificação , Oxidantes/química , Ácido Peroxinitroso/metabolismo , Glutarredoxinas/química , Glutationa/química , Glutationa/metabolismo , Dissulfeto de Glutationa/isolamento & purificação , Proteínas de Fluorescência Verde/química , Peróxido de Hidrogênio/química , Óxido Nítrico/química , Óxido Nítrico/metabolismo , Oxidantes/metabolismo , Oxirredução , Ácido Peroxinitroso/química , Fagócitos/metabolismo , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo
20.
BMC Public Health ; 16: 307, 2016 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-27066890

RESUMO

BACKGROUND: Over the past two decades research on sexual and gender minority (lesbian, gay, bisexual and transgender; LGBT) health has highlighted substantial health disparities based on sexual orientation and gender identity in many parts of the world. We systematically reviewed the literature on sexual minority women's (SMW) health in Southern Africa, with the objective of identifying existing evidence and pointing out knowledge gaps around the health of this vulnerable group in this region. METHODS: A systematic review of publications in English, French, Portuguese or German, indexed in PubMed or MEDLINE between the years 2000 and 2015, following PRISMA guidelines. Additional studies were identified by searching bibliographies of identified studies. Search terms included (Lesbian OR bisexual OR "women who have sex with women"), (HIV OR depression OR "substance use" OR "substance abuse" OR "mental health" OR suicide OR anxiety OR cancer), and geographical specification. All empirical studies that used quantitative or qualitative methods, which contributed to evidence for SMW's health in one, a few or all of the countries, were included. Theoretical and review articles were excluded. Data were extracted independently by 2 researchers using predefined data fields, which included a risk of bias/quality assessment. RESULTS: Of 315 hits, 9 articles were selected for review and a further 6 were identified through bibliography searches. Most studies were conducted with small sample sizes in South Africa and focused on sexual health. SMW included in the studies were racially and socio-economically heterogeneous. Studies focused predominately on young populations, and highlighted substance use and violence as key health issues for SMW in Southern Africa. CONCLUSIONS: Although there are large gaps in the literature, the review highlighted substantial sexual-orientation-related health disparities among women in Southern Africa. The findings have important implications for public health policy and research, highlighting the lack of population-level evidence on the one hand, and the impact of criminalizing laws around homosexuality on the other hand.


Assuntos
Minorias Sexuais e de Gênero , Saúde da Mulher , África Austral , Feminino , Humanos
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