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1.
Cancers (Basel) ; 15(19)2023 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-37835392

RESUMO

In myelofibrosis, comorbidities (CMs) add prognostic information independently from the Dynamic International Prognostic Scoring System (DIPSS). The Myelodysplastic Syndrome-Specific Comorbidity Index (MDS-CI) offers a simple tool for CM assessment as it is calculable after having performed a careful history and physical examination, a small routine chemistry panel (including creatinine and liver enzymes) and a limited set of functional diagnostics. To assess the prognostic impact of the MDS-CI in addition to the DIPSS and the Mutation-Enhanced International Prognostic Scoring System (MIPSS)-70, we performed a retrospective chart review of 70 MF patients who had not received allogeneic stem cell transplantation (primary MF, n = 51; secondary MF, n = 19; median follow-up, 40 months) diagnosed at our institution between 2000 and 2020. Cardiac diseases (23/70) and solid tumors (12/70) were the most common CMs observed at MF diagnosis. Overall survival (OS) was significantly influenced by the MDS-CI (median OS MDS-CI low (n = 38): 101 months; MDS-CI intermediate (n = 25): 50 months; and high (n = 7): 8 months; p < 0.001). The MDS-CI added prognostic information after inclusion as a categorical variable in a multivariate model together with the dichotomized DIPSS or the dichotomized MIPSS70: MDS-CI high HR 14.64 (95% CI 4.42; 48.48), p = 0.0002, and MDS-CI intermediate HR 1.97 (95% CI 0.96; 4.03), p = 0.065, and MDS-CI high HR 19.65 (95% CI 4.71; 81.95), p < 0.001, and MDS-CI intermediate HR 1.063 (95% CI 0.65; 4.06), p = 0.2961, respectively. The analysis of our small and retrospective MF cohort suggests that the MDS-CI represents a useful tool to identify MF patients with an increased vulnerability due to comorbidities. However, analyses of larger cohorts are necessary to define the value of the MDS-CI as a prognostic tool in comparison with other comorbidity indices.

2.
Cancers (Basel) ; 15(5)2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36900271

RESUMO

In myelofibrosis, the C-reactive protein (CRP)/albumin ratio (CAR) and the Glasgow Prognostic Score (GPS) add prognostic information independently of the Dynamic International Prognostic Scoring System (DIPSS). Their prognostic impact, if molecular aberrations are considered, is currently unknown. We performed a retrospective chart review of 108 MF patients (prefibrotic MF n = 30; primary MF n = 56; secondary MF n = 22; median follow-up 42 months). In MF, both a CAR > 0.347 and a GPS > 0 were associated with a shorter median overall survival (21 [95% CI 0-62] vs. 80 months [95% CI 57-103], p < 0.001 and 32 [95% CI 1-63] vs. 89 months [95% CI 65-113], p < 0.001). Both parameters retained their prognostic value after inclusion into a bivariate Cox regression model together with the dichotomized Mutation-Enhanced International Prognostic Scoring System (MIPSS)-70: CAR > 0.374 HR 3.53 [95% CI 1.36-9.17], p = 0.0095 and GPS > 0 HR 4.63 [95% CI 1.76-12.1], p = 0.0019. An analysis of serum samples from an independent cohort revealed a correlation of CRP with levels of interleukin-1ß and albumin with TNF-α, and demonstrated that CRP was correlated to the variant allele frequency of the driver mutation, but not albumin. Albumin and CRP as parameters readily available in clinical routine at low costs deserve further evaluation as prognostic markers in MF, ideally by analyzing data from prospective and multi-institutional registries. Since both albumin and CRP levels reflect different aspects of MF-associated inflammation and metabolic changes, our study further highlights that combining both parameters seems potentially useful to improve prognostication in MF.

3.
Blood ; 141(17): 2127-2140, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-36758212

RESUMO

JAK 2-V617F mutation causes myeloproliferative neoplasms (MPNs) that can manifest as polycythemia vera (PV), essential thrombocythemia (ET), or primary myelofibrosis. At diagnosis, patients with PV already exhibited iron deficiency, whereas patients with ET had normal iron stores. We examined the influence of iron availability on MPN phenotype in mice expressing JAK2-V617F and in mice expressing JAK2 with an N542-E543del mutation in exon 12 (E12). At baseline, on a control diet, all JAK2-mutant mouse models with a PV-like phenotype displayed iron deficiency, although E12 mice maintained more iron for augmented erythropoiesis than JAK2-V617F mutant mice. In contrast, JAK2-V617F mutant mice with an ET-like phenotype had normal iron stores comparable with that of wild-type (WT) mice. On a low-iron diet, JAK2-mutant mice and WT controls increased platelet production at the expense of erythrocytes. Mice with a PV phenotype responded to parenteral iron injections by decreasing platelet counts and further increasing hemoglobin and hematocrit, whereas no changes were observed in WT controls. Alterations of iron availability primarily affected the premegakaryocyte-erythrocyte progenitors, which constitute the iron-responsive stage of hematopoiesis in JAK2-mutant mice. The orally administered ferroportin inhibitor vamifeport and the minihepcidin PR73 normalized hematocrit and hemoglobin levels in JAK2-V617F and E12 mutant mouse models of PV, suggesting that ferroportin inhibitors and minihepcidins could be used in the treatment for patients with PV.


Assuntos
Deficiências de Ferro , Transtornos Mieloproliferativos , Policitemia Vera , Trombocitemia Essencial , Camundongos , Animais , Ferro , Transtornos Mieloproliferativos/tratamento farmacológico , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/diagnóstico , Policitemia Vera/genética , Janus Quinase 2/genética , Trombocitemia Essencial/genética , Mutação , Fenótipo , Hemoglobinas/genética
4.
Haematologica ; 108(9): 2316-2330, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36475518

RESUMO

Mono-allelic germline disruptions of the transcription factor GATA2 result in a propensity for developing myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML), affecting more than 85% of carriers. How a partial loss of GATA2 functionality enables leukemic transformation years later is unclear. This question has remained unsolved mainly due to the lack of informative models, as Gata2 heterozygote mice do not develop hematologic malignancies. Here we show that two different germline Gata2 mutations (TgErg/Gata2het and TgErg/Gata2L359V) accelerate AML in mice expressing the human hematopoietic stem cell regulator ERG. Analysis of Erg/Gata2het fetal liver and bone marrow-derived hematopoietic cells revealed a distinct pre-leukemic phenotype. This was characterized by enhanced transition from stem to progenitor state, increased proliferation, and a striking mitochondrial phenotype, consisting of highly expressed oxidative-phosphorylation-related gene sets, elevated oxygen consumption rates, and notably, markedly distorted mitochondrial morphology. Importantly, the same mitochondrial gene-expression signature was observed in human AML harboring GATA2 aberrations. Similar to the observations in mice, non-leukemic bone marrows from children with germline GATA2 mutation demonstrated marked mitochondrial abnormalities. Thus, we observed the tumor suppressive effects of GATA2 in two germline Gata2 genetic mouse models. As oncogenic mutations often accumulate with age, GATA2 deficiency-mediated priming of hematopoietic cells for oncogenic transformation may explain the earlier occurrence of MDS/AML in patients with GATA2 germline mutation. The mitochondrial phenotype is a potential therapeutic opportunity for the prevention of leukemic transformation in these patients.


Assuntos
Deficiência de GATA2 , Leucemia Mieloide Aguda , Síndromes Mielodisplásicas , Criança , Humanos , Camundongos , Animais , Deficiência de GATA2/genética , Síndromes Mielodisplásicas/patologia , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Medula Óssea/patologia , Células-Tronco Hematopoéticas/metabolismo , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Fator de Transcrição GATA2/genética , Fator de Transcrição GATA2/metabolismo
5.
Glob Chall ; 6(10): 2200082, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36275356

RESUMO

The Li-ion hybrid capacitor (LIHC) system explores the possibility of achieving both high energy and power density in a single energy storage system with an intercalation anode and capacitive cathode. However, to achieve a high power and energy-based system, the properties of the cathode electrode material are vital. Here, bio-waste plant stem-derived activated porous carbon is explored as a cathode for LIHC application. A specific surface area of 1826 m2 g-1, enhanced degree of crystallinity, and graphitization results for porous carbon from activation by potassium hydroxide. When employed as supercapacitor material, the device exhibits good rate capability, energy, and power attributes with a specific capacitance of 116 F g-1 (1 A g-1). Simultaneously when tested for LIHC application the formulated device shows good capacity retention for 2500 cycles with a high energy density of 125 Wh kg-1 at a power density of 69 W kg-1. The work demonstrates unique, cost-effective strategy to develop a crystalline high surface area carbon from any such bio-waste sources to be employed as potential electrodes for energy storage applications.

6.
Front Immunol ; 13: 870720, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35711460

RESUMO

Background: Allergic asthma is a chronic disease and medical treatment often fails to fully control the disease in the long term, leading to a great need for new therapeutic approaches. Immunoproteasome inhibition impairs T helper cell function and is effective in many (auto-) inflammatory settings but its effect on allergic airway inflammation is unknown. Methods: Immunoproteasome expression was analyzed in in vitro polarized T helper cell subsets. To study Th2 cells in vivo acute allergic airway inflammation was induced in GATIR (GATA-3-vYFP reporter) mice using ovalbumin and house dust mite extract. Mice were treated with the immunoproteasome inhibitor ONX 0914 or vehicle during the challenge phase and the induction of airway inflammation was analyzed. Results: In vitro polarized T helper cell subsets (Th1, Th2, Th17, and Treg) express high levels of immunoproteasome subunits. GATIR mice proved to be a useful tool for identification of Th2 cells. Immunoproteasome inhibition reduced the Th2 response in both airway inflammation models. Furthermore, T cell activation and antigen-specific cytokine secretion was impaired and a reduced infiltration of eosinophils and professional antigen-presenting cells into the lung and the bronchoalveolar space was observed in the ovalbumin model. Conclusion: These results show the importance of the immunoproteasome in Th2 cells and airway inflammation. Our data provides first insight into the potential of using immunoproteasome inhibition to target the aberrant Th2 response, e.g. in allergic airway inflammation.


Assuntos
Asma , Células Th2 , Animais , Asma/tratamento farmacológico , Asma/metabolismo , Modelos Animais de Doenças , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Camundongos , Ovalbumina/farmacologia , Células Th17 , Células Th2/metabolismo
7.
Sci Adv ; 7(37): eabi4852, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34516881

RESUMO

A considerable number of patients with cancer suffer from anemia, which has detrimental effects on quality of life and survival. The mechanisms underlying tumor-associated anemia are multifactorial and poorly understood. Therefore, we aimed at systematically assessing the patho-etiology of tumor-associated anemia in mice. We demonstrate that reduced red blood cell (RBC) survival rather than altered erythropoiesis is driving the development of anemia. The tumor-induced inflammatory and metabolic remodeling affect RBC integrity and augment splenic phagocyte activity promoting erythrophagocytosis. Exercise training normalizes these tumor-associated abnormal metabolic profiles and inflammation and thereby ameliorates anemia, in part, by promoting RBC survival. Fatigue was prevented in exercising tumor-bearing mice. Thus, exercise has the unique potential to substantially modulate metabolism and inflammation and thereby counteracts pathological remodeling of these parameters by the tumor microenvironment. Translation of this finding to patients with cancer could have a major impact on quality of life and potentially survival.

8.
Cancers (Basel) ; 13(13)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34209457

RESUMO

Myelodysplastic syndromes (MDS) represent a heterogeneous group of clonal disorders caused by sequential accumulation of somatic driver mutations in hematopoietic stem and progenitor cells (HSPCs). MDS is characterized by ineffective hematopoiesis with cytopenia, dysplasia, inflammation, and a variable risk of transformation into secondary acute myeloid leukemia. The advent of next-generation sequencing has revolutionized our understanding of the genetic basis of the disease. Nevertheless, the biology of clonal evolution remains poorly understood, and the stochastic genetic drift with sequential accumulation of genetic hits in HSPCs is individual, highly dynamic and hardly predictable. These continuously moving genetic targets pose substantial challenges for the implementation of precision medicine, which aims to maximize efficacy with minimal toxicity of treatments. In the current postgenomic era, allogeneic hematopoietic stem cell transplantation remains the only curative option for younger and fit MDS patients. For all unfit patients, regeneration of HSPCs stays out of reach and all available therapies remain palliative, which will eventually lead to refractoriness and progression. In this review, we summarize the recent advances in our understanding of MDS pathophysiology and its impact on diagnosis, risk-assessment and disease monitoring. Moreover, we present ongoing clinical trials with targeting compounds and highlight future perspectives for precision medicine.

9.
Cell Microbiol ; 23(9): e13367, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34029434

RESUMO

Aspergillus flavus is a leading cause of corneal infections in India and worldwide, resulting in severe visual impairment. We studied the host immune response towards A. flavus in immortalised human corneal epithelial cells (HCEC) and found increased expression of Toll-like receptors, antimicrobial peptides and proinflammatory cytokines like IL-6 and IL-8. Differential expressions of antimicrobial peptides were determined in corneal scrapings from A. flavus keratitis patients with significantly increased expression of LL-37, S100A12 and RNase 7. Increased levels of IL-22 expression were observed both in patients with A. flavus keratitis and in experimental mice model of corneal infections along with IL-17, IL-23 and IL-18. IL-22 is an important mediator of inflammation during microbial infections, and acts primarily on fibroblasts and epithelial cells. We observed constitutive expression of IL-22 receptors in HCEC, and IL-22 mediated activation of NF-κB, MAPK pathways and STAT3, along with increased expression of antimicrobial peptides in these cells. IL-22 also efficiently lessened cell deaths in corneal epithelial cells during A. flavus infection in vitro. Furthermore, recombinant IL-22 reduced fungal burden and corneal opacity in an experimental murine model of A. flavus keratitis.


Assuntos
Aspergillus flavus , Ceratite , Animais , Peptídeos Antimicrobianos , Modelos Animais de Doenças , Células Epiteliais , Humanos , Imunidade , Interleucinas , Camundongos , Interleucina 22
10.
Blood ; 137(16): 2139-2151, 2021 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-33667305

RESUMO

We studied a subset of hematopoietic stem cells (HSCs) that are defined by elevated expression of CD41 (CD41hi) and showed bias for differentiation toward megakaryocytes (Mks). Mouse models of myeloproliferative neoplasms (MPNs) expressing JAK2-V617F (VF) displayed increased frequencies and percentages of the CD41hi vs CD41lo HSCs compared with wild-type controls. An increase in CD41hi HSCs that correlated with JAK2-V617F mutant allele burden was also found in bone marrow from patients with MPN. CD41hi HSCs produced a higher number of Mk-colonies of HSCs in single-cell cultures in vitro, but showed reduced long-term reconstitution potential compared with CD41lo HSCs in competitive transplantations in vivo. RNA expression profiling showed an upregulated cell cycle, Myc, and oxidative phosphorylation gene signatures in CD41hi HSCs, whereas CD41lo HSCs showed higher gene expression of interferon and the JAK/STAT and TNFα/NFκB signaling pathways. Higher cell cycle activity and elevated levels of reactive oxygen species were confirmed in CD41hi HSCs by flow cytometry. Expression of Epcr, a marker for quiescent HSCs inversely correlated with expression of CD41 in mice, but did not show such reciprocal expression pattern in patients with MPN. Treatment with interferon-α further increased the frequency and percentage of CD41hi HSCs and reduced the number of JAK2-V617F+ HSCs in mice and patients with MPN. The shift toward the CD41hi subset of HSCs by interferon-α provides a possible mechanism of how interferon-α preferentially targets the JAK2 mutant clone.


Assuntos
Interferon-alfa/uso terapêutico , Janus Quinase 2/genética , Megacariócitos/metabolismo , Transtornos Mieloproliferativos/genética , Animais , Técnicas de Introdução de Genes , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Megacariócitos/citologia , Camundongos , Camundongos Transgênicos , Transtornos Mieloproliferativos/tratamento farmacológico , Glicoproteína IIb da Membrana de Plaquetas/genética , Mutação Puntual/efeitos dos fármacos
11.
Micromachines (Basel) ; 12(2)2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33672467

RESUMO

Functionalized carbon nanotube (FCNT) and Manganese Oxide (MnO2) nanoflower hybrid material was synthesized using hydrothermal technique as a promising electrode material for supercapacitor applications. The morphological investigation revealed the formation of 'nanoflower' like structure of MnO2 connected with FCNT, thus paving an easy path for the conduction of electrons during the electrochemical mechanism. A significant improvement in capacitance properties was observed in the hybrid material, in which carbon nanotube acts as a conducting cylindrical path, while the major role of MnO2 was to store the charge, acting as an electrolyte reservoir leading to an overall improved electrochemical performance. The full cell electrochemical analysis of FCNT-MnO2 hybrid using 3 M potassium hydroxide (KOH) electrolyte indicated a specific capacitance of 359.53 F g-1, specific energy of 49.93 Wh kg-1 and maximum specific power of 898.84 W kg-1 at 5 mV s-1. The results show promise for the future of supercapacitor development based on hybrid electrode materials, where high specific energy can be achieved along with high specific power and long cycle life.

12.
Toni M. Delorey; Carly G. K. Ziegler; Graham Heimberg; Rachelly Normand; Yiming Yang; Asa Segerstolpe; Domenic Abbondanza; Stephen J. Fleming; Ayshwarya Subramanian; Daniel T. Montoro; Karthik A. Jagadeesh; Kushal Dey; Pritha Sen; Michal Slyper; Yered Pita-Juarez; Devan Phillips; Zohar Bloom-Ackermann; Nick Barkas; Andrea Ganna; James Gomez; Erica Normandin; Pourya Naderi; Yury V. Popov; Siddharth S. Raju; Sebastian Niezen; Linus T.-Y. Tsai; Katherine J. Siddle; Malika Sud; Victoria M. Tran; Shamsudheen Karuthedath Vellarikkal; Liat Amir-Zilberstein; Joseph M Beechem; Olga R. Brook; Jonathan Chen; Prajan Divakar; Phylicia Dorceus; Jesse M Engreitz; Adam Essene; Donna M. Fitzgerald; Robin Fropf; Steven Gazal; Joshua Gould; Tyler Harvey; Jonathan Hecht; Tyler Hether; Judit Jane-Valbuena; Michael Leney-Greene; Hui Ma; Cristin McCabe; Daniel E. McLoughlin; Eric M. Miller; Christoph Muus; Mari Niemi; Robert Padera; Liuliu Pan; Deepti Pant; Jenna Pfiffner-Borges; Christopher J. Pinto; Jason Reeves; Marty Ross; Melissa Rudy; Erroll H. Rueckert; Michelle Siciliano; Alexander Sturm; Ellen Todres; Avinash Waghray; Sarah Warren; Shuting Zhang; Dan Zollinger; Lisa Cosimi; Rajat M Gupta; Nir Hacohen; Winston Hide; Alkes L. Price; Jayaraj Rajagopal; Purushothama Rao Tata; Stefan Riedel; Gyongyi Szabo; Timothy L. Tickle; Deborah Hung; Pardis C. Sabeti; Richard Novak; Robert Rogers; Donald E. Ingber; Z Gordon Jiang; Dejan Juric; Mehrtash Babadi; Samouil L. Farhi; James R. Stone; Ioannis S. Vlachos; Isaac H. Solomon; Orr Ashenberg; Caroline B.M. Porter; Bo Li; Alex K. Shalek; Alexandra-Chloe Villani; Orit Rozenblatt-Rosen; Aviv Regev.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-430130

RESUMO

The SARS-CoV-2 pandemic has caused over 1 million deaths globally, mostly due to acute lung injury and acute respiratory distress syndrome, or direct complications resulting in multiple-organ failures. Little is known about the host tissue immune and cellular responses associated with COVID-19 infection, symptoms, and lethality. To address this, we collected tissues from 11 organs during the clinical autopsy of 17 individuals who succumbed to COVID-19, resulting in a tissue bank of approximately 420 specimens. We generated comprehensive cellular maps capturing COVID-19 biology related to patients demise through single-cell and single-nucleus RNA-Seq of lung, kidney, liver and heart tissues, and further contextualized our findings through spatial RNA profiling of distinct lung regions. We developed a computational framework that incorporates removal of ambient RNA and automated cell type annotation to facilitate comparison with other healthy and diseased tissue atlases. In the lung, we uncovered significantly altered transcriptional programs within the epithelial, immune, and stromal compartments and cell intrinsic changes in multiple cell types relative to lung tissue from healthy controls. We observed evidence of: alveolar type 2 (AT2) differentiation replacing depleted alveolar type 1 (AT1) lung epithelial cells, as previously seen in fibrosis; a concomitant increase in myofibroblasts reflective of defective tissue repair; and, putative TP63+ intrapulmonary basal-like progenitor (IPBLP) cells, similar to cells identified in H1N1 influenza, that may serve as an emergency cellular reserve for severely damaged alveoli. Together, these findings suggest the activation and failure of multiple avenues for regeneration of the epithelium in these terminal lungs. SARS-CoV-2 RNA reads were enriched in lung mononuclear phagocytic cells and endothelial cells, and these cells expressed distinct host response transcriptional programs. We corroborated the compositional and transcriptional changes in lung tissue through spatial analysis of RNA profiles in situ and distinguished unique tissue host responses between regions with and without viral RNA, and in COVID-19 donor tissues relative to healthy lung. Finally, we analyzed genetic regions implicated in COVID-19 GWAS with transcriptomic data to implicate specific cell types and genes associated with disease severity. Overall, our COVID-19 cell atlas is a foundational dataset to better understand the biological impact of SARS-CoV-2 infection across the human body and empowers the identification of new therapeutic interventions and prevention strategies.

13.
Nanoscale Adv ; 3(16): 4834-4842, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-36134311

RESUMO

Phosphorus (P) is a limiting macronutrient that regulates plant growth and development based on the bioavailability of its inorganic form, i.e., orthophosphate (Pi). P plays a critical role in cell development, and it is a key component of ATP, DNA, lipids, and cell signaling machinery. Without the exogenous application of P fertilizers, the yield of crops will not meet the ever-growing demand in today's world. However, due to the non-renewable nature of natural P reserves and simultaneous rapid human population growth, food crops must be ultimately produced more than ever by using a lower P fertilizer input. Hence, the strategy of preparing nano-fertilizers was conceptualized and demonstrated with great success. For example, nano-diammonium phosphate (n-DAP) performed far better than the commercial granular DAP (c-DAP). However, nano-fertilizers, including n-DAP, cannot be produced on a large scale using the available processing methods. Herein, a novel processing strategy, namely cryo-milling, is demonstrated to prepare n-DAP on a kg-scale without altering DAP's bonding structure. Cryo-milling involves milling at liquid N2 temperatures and therefore helps in brittle fracture of coarser DAP particles into n-DAP particles. Cryo-milled n-DAP, with particle size ∼5000 times smaller but specific surface area ∼14 000 times greater than that of c-DAP, enhanced the growth of monocot (wheat) and dicot (tomato) plants due to improved bioavailability of Pi even for a far lower input than c-DAP. Phenotypic observations such as higher leaf biomass, longer shoots, shorter roots, and less anthocyanin pigmentation manifested the extraordinary efficacy of cryo-milled n-DAP for 75% lower input than c-DAP.

14.
Stem Cell Reports ; 15(5): 1067-1079, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33125875

RESUMO

The role of leptin receptor (OB-R) signaling in linking pluripotency with growth and development and the consequences of dysfunctional leptin signaling on progression of metabolic disease is poorly understood. Using a global unbiased proteomics approach we report that embryonic fibroblasts (MEFs) carrying the db/db mutation exhibit metabolic abnormalities, while their reprogrammed induced pluripotent stem cells (iPSCs) show altered expression of proteins involved in embryonic development. An upregulation in expression of eukaryotic translation initiation factor 4e (Eif4e) and Stat3 binding to the Eif4e promoter was supported by enhanced protein synthesis in mutant iPSCs. Directed differentiation of db/db iPSCs toward the neuronal lineage showed defects. Gene editing to correct the point mutation in db/db iPSCs using CRISPR-Cas9, restored expression of neuronal markers and protein synthesis while reversing the metabolic defects. These data imply a direct role for OB-R in regulating metabolism in embryonic fibroblasts and key developmental pathways in iPSCs.


Assuntos
Fator de Iniciação 4E em Eucariotos/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Biossíntese de Proteínas , Receptores para Leptina/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Animais , Sistemas CRISPR-Cas , Diferenciação Celular , Linhagem da Célula , Fator de Iniciação 4E em Eucariotos/genética , Fibroblastos/metabolismo , Edição de Genes , Regulação da Expressão Gênica no Desenvolvimento , Metaboloma , Camundongos , Camundongos Knockout , Neurogênese , Proteínas , Proteômica , Receptores para Leptina/genética
15.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-251207

RESUMO

While vaccines are vital for preventing COVID-19 infections, it is critical to develop new therapies to treat patients who become infected. Pharmacological targeting of a host factor required for viral replication can suppress viral spread with a low probability of viral mutation leading to resistance. In particular, host kinases are highly druggable targets and a number of conserved coronavirus proteins, notably the nucleoprotein (N), require phosphorylation for full functionality. In order to understand how targeting kinases could be used to compromise viral replication, we used a combination of phosphoproteomics and bioinformatics as well as genetic and pharmacological kinase inhibition to define the enzymes important for SARS-CoV-2 N protein phosphorylation and viral replication. From these data, we propose a model whereby SRPK1/2 initiates phosphorylation of the N protein, which primes for further phosphorylation by GSK-3/{beta} and CK1 to achieve extensive phosphorylation of the N protein SR-rich domain. Importantly, we were able to leverage our data to identify an FDA-approved kinase inhibitor, Alectinib, that suppresses N phosphorylation by SRPK1/2 and limits SARS-CoV-2 replication. Together, these data suggest that repurposing or developing novel host-kinase directed therapies may be an efficacious strategy to prevent or treat COVID-19 and other coronavirus-mediated diseases.

16.
Hemasphere ; 4(3): e371, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32647796

RESUMO

Myeloproliferative neoplasms (MPNs) are characterized by deregulation of mature blood cell production and increased risk of myelofibrosis (MF) and leukemic transformation. Numerous driver mutations have been identified but substantial disease heterogeneity remains unexplained, implying the involvement of additional as yet unidentified factors. The inflammatory microenvironment has recently attracted attention as a crucial factor in MPN biology, in particular whether inflammatory cytokines and chemokines contribute to disease establishment or progression. Here we present a large-scale study of serum cytokine profiles in more than 400 MPN patients and identify an essential thrombocythemia (ET)-specific inflammatory cytokine signature consisting of Eotaxin, GRO-α, and EGF. Levels of 2 of these markers (GRO-α and EGF) in ET patients were associated with disease transformation in initial sample collection (GRO-α) or longitudinal sampling (EGF). In ET patients with extensive genomic profiling data (n = 183) cytokine levels added significant prognostic value for predicting transformation from ET to MF. Furthermore, CD56+CD14+ pro-inflammatory monocytes were identified as a novel source of increased GRO-α levels. These data implicate the immune cell microenvironment as a significant player in ET disease evolution and illustrate the utility of cytokines as potential biomarkers for reaching beyond genomic classification for disease stratification and monitoring.

18.
J Immunol ; 204(9): 2600-2611, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32213568

RESUMO

Accurately tuned expression levels of the transcription factor GATA-3 are crucial at several stages of T cell and innate lymphoid cell development and differentiation. Moreover, several lines of evidence suggest that Gata3 expression might provide a reliable molecular marker for the identification of elusive progenitor cell subsets at the earliest stages of T lineage commitment. To be able to faithfully monitor Gata3 expression noninvasively at the single-cell level, we have generated a novel strain of knock-in reporter mice, termed GATIR, by inserting an expression cassette encoding a bright fluorescent marker into the 3'-untranslated region of the endogenous Gata3 locus. Importantly, in contrast to three previously published strains of Gata3 reporter mice, GATIR mice preserve physiological Gata3 expression on the targeted allele. In this study, we show that GATIR mice faithfully reflect endogenous Gata3 expression without disturbing the development of GATA-3-dependent lymphoid cell populations. We further show that GATIR mice provide an ideal tool for noninvasive monitoring of Th2 polarization and straightforward identification of innate lymphoid cell 2 progenitor populations. Finally, as our reporter is non-gene-destructive, GATIR mice can be bred to homozygosity, not feasible with previously published strains of Gata3 reporter mice harboring disrupted alleles. The availability of hetero- and homozygous Gata3 reporter mice with an exceptionally bright fluorescent marker, allowed us to visualize allelic Gata3 expression in individual cells simply by flow cytometry. The unambiguous results obtained provide compelling evidence against previously postulated monoallelic Gata3 expression in early T lineage and hematopoietic stem cell subsets.


Assuntos
Fator de Transcrição GATA3/genética , Genes Reporter/genética , Regiões 3' não Traduzidas/genética , Regiões 3' não Traduzidas/imunologia , Alelos , Animais , Biomarcadores/metabolismo , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Linhagem da Célula/genética , Linhagem da Célula/imunologia , Feminino , Citometria de Fluxo/métodos , Corantes Fluorescentes/metabolismo , Fator de Transcrição GATA3/imunologia , Técnicas de Introdução de Genes/métodos , Genes Reporter/imunologia , Células-Tronco Hematopoéticas/imunologia , Imunidade Inata/genética , Imunidade Inata/imunologia , Linfócitos/imunologia , Células Progenitoras Linfoides/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T/imunologia
19.
Glob Chall ; 4(1): 1900048, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31956425

RESUMO

Carbon-SnO x composites are obtained by impregnating acetylacetone-treated, delignified wood fibers with tin precursor and successively carbonizing at 1000 °C in 95% argon and 5% oxygen. Scanning electron microscopy and nitrogen sorption studies (Brunauer-Emmett-Teller) show that acetylacetone treatment stabilizes the wood fiber structure during carbonization at 1000 °C and preserves the porous structural features. X-ray diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy studies show that the small amount of oxygen introduced in inert atmosphere passivates the surface of tin nanoparticles. The passivation process yields thermally and electrochemically stable SnO x particles embedded in carbon matrix. The resultant carbon-SnO x material with 16 wt% SnO x shows excellent electrochemical performance of rate capability from 0.1 to 10 A g-1 and cycling stability for 1000 cycles with Li-ion storage capacity of 280 mAh g-1 at a current density of 10 A g-1. The remarkable electrochemical performance of wood-derived carbon-SnO x composite is attributed to the reproduction of structural featured wood fibers to nanoscale in carbon-SnO x composite and controlled passivation of tin nanoparticles to yield SnO x nanoparticles.

20.
Blood ; 134(21): 1832-1846, 2019 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-31511238

RESUMO

Increased energy requirement and metabolic reprogramming are hallmarks of cancer cells. We show that metabolic alterations in hematopoietic cells are fundamental to the pathogenesis of mutant JAK2-driven myeloproliferative neoplasms (MPNs). We found that expression of mutant JAK2 augmented and subverted metabolic activity of MPN cells, resulting in systemic metabolic changes in vivo, including hypoglycemia, adipose tissue atrophy, and early mortality. Hypoglycemia in MPN mouse models correlated with hyperactive erythropoiesis and was due to a combination of elevated glycolysis and increased oxidative phosphorylation. Modulating nutrient supply through high-fat diet improved survival, whereas high-glucose diet augmented the MPN phenotype. Transcriptomic and metabolomic analyses identified numerous metabolic nodes in JAK2-mutant hematopoietic stem and progenitor cells that were altered in comparison with wild-type controls. We studied the consequences of elevated levels of Pfkfb3, a key regulatory enzyme of glycolysis, and found that pharmacological inhibition of Pfkfb3 with the small molecule 3PO reversed hypoglycemia and reduced hematopoietic manifestations of MPNs. These effects were additive with the JAK1/2 inhibitor ruxolitinib in vivo and in vitro. Inhibition of glycolysis by 3PO altered the redox homeostasis, leading to accumulation of reactive oxygen species and augmented apoptosis rate. Our findings reveal the contribution of metabolic alterations to the pathogenesis of MPNs and suggest that metabolic dependencies of mutant cells represent vulnerabilities that can be targeted for treating MPNs.


Assuntos
Células-Tronco Hematopoéticas/metabolismo , Janus Quinase 2/genética , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/metabolismo , Animais , Humanos , Camundongos , Mutação
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