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1.
Nat Immunol ; 21(10): 1194-1204, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32895539

RESUMO

Early atherosclerosis depends upon responses by immune cells resident in the intimal aortic wall. Specifically, the healthy intima is thought to be populated by vascular dendritic cells (DCs) that, during hypercholesterolemia, initiate atherosclerosis by being the first to accumulate cholesterol. Whether these cells remain key players in later stages of disease is unknown. Using murine lineage-tracing models and gene expression profiling, we reveal that myeloid cells present in the intima of the aortic arch are not DCs but instead specialized aortic intima resident macrophages (MacAIR) that depend upon colony-stimulating factor 1 and are sustained by local proliferation. Although MacAIR comprise the earliest foam cells in plaques, their proliferation during plaque progression is limited. After months of hypercholesterolemia, their presence in plaques is overtaken by recruited monocytes, which induce MacAIR-defining genes. These data redefine the lineage of intimal phagocytes and suggest that proliferation is insufficient to sustain generations of macrophages during plaque progression.


Assuntos
Aorta/imunologia , Macrófagos/imunologia , Monócitos/imunologia , Placa Aterosclerótica/imunologia , Túnica Íntima/imunologia , Animais , Diferenciação Celular , Linhagem da Célula , Movimento Celular , Proliferação de Células , Células Cultivadas , Colesterol/metabolismo , Progressão da Doença , Humanos , Fator Estimulador de Colônias de Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Parabiose , Fagocitose
2.
Immunity ; 54(1): 44-52.e3, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33338412

RESUMO

Memory T cell responses have been demonstrated in COVID-19 convalescents, but ex vivo phenotypes of SARS-CoV-2-specific T cells have been unclear. We detected SARS-CoV-2-specific CD8+ T cells by MHC class I multimer staining and examined their phenotypes and functions in acute and convalescent COVID-19. Multimer+ cells exhibited early differentiated effector-memory phenotypes in the early convalescent phase. The frequency of stem-like memory cells was increased among multimer+ cells in the late convalescent phase. Cytokine secretion assays combined with MHC class I multimer staining revealed that the proportion of interferon-γ (IFN-γ)-producing cells was significantly lower among SARS-CoV-2-specific CD8+ T cells than those specific to influenza A virus. Importantly, the proportion of IFN-γ-producing cells was higher in PD-1+ cells than PD-1- cells among multimer+ cells, indicating that PD-1-expressing, SARS-CoV-2-specific CD8+ T cells are not exhausted, but functional. Our current findings provide information for understanding of SARS-CoV-2-specific CD8+ T cells elicited by infection or vaccination.


Assuntos
Linfócitos T CD8-Positivos/imunologia , COVID-19/imunologia , Receptor de Morte Celular Programada 1/metabolismo , SARS-CoV-2/imunologia , Reação de Fase Aguda/imunologia , Reação de Fase Aguda/virologia , COVID-19/patologia , COVID-19/virologia , Convalescença , Epitopos de Linfócito T , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Memória Imunológica , Imunofenotipagem , Interferon gama/metabolismo , Ativação Linfocitária , Carga Viral
3.
Nature ; 578(7796): 572-576, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32051590

RESUMO

Levels of gene expression underpin organismal phenotypes1,2, but the nature of selection that acts on gene expression and its role in adaptive evolution remain unknown1,2. Here we assayed gene expression in rice (Oryza sativa)3, and used phenotypic selection analysis to estimate the type and strength of selection on the levels of more than 15,000 transcripts4,5. Variation in most transcripts appears (nearly) neutral or under very weak stabilizing selection in wet paddy conditions (with median standardized selection differentials near zero), but selection is stronger under drought conditions. Overall, more transcripts are conditionally neutral (2.83%) than are antagonistically pleiotropic6 (0.04%), and transcripts that display lower levels of expression and stochastic noise7-9 and higher levels of plasticity9 are under stronger selection. Selection strength was further weakly negatively associated with levels of cis-regulation and network connectivity9. Our multivariate analysis suggests that selection acts on the expression of photosynthesis genes4,5, but that the efficacy of selection is genetically constrained under drought conditions10. Drought selected for earlier flowering11,12 and a higher expression of OsMADS18 (Os07g0605200), which encodes a MADS-box transcription factor and is a known regulator of early flowering13-marking this gene as a drought-escape gene11,12. The ability to estimate selection strengths provides insights into how selection can shape molecular traits at the core of gene action.


Assuntos
Regulação da Expressão Gênica de Plantas , Oryza/genética , Seleção Genética/genética , Secas , Evolução Molecular , Flores/genética , Flores/crescimento & desenvolvimento , Aptidão Genética/genética , Oryza/crescimento & desenvolvimento , Fotossíntese/genética , Folhas de Planta/genética , RNA Mensageiro/análise , RNA Mensageiro/genética , Fatores de Tempo , Fatores de Transcrição/metabolismo
4.
Proc Natl Acad Sci U S A ; 120(49): e2314416120, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38011559

RESUMO

Despite the remarkable clinical success of immunotherapies in a subset of cancer patients, many fail to respond to treatment and exhibit resistance. Here, we found that genetic or pharmacologic inhibition of the lipid kinase PIKfyve, a regulator of autophagic flux and lysosomal biogenesis, upregulated surface expression of major histocompatibility complex class I (MHC-I) in cancer cells via impairing autophagic flux, resulting in enhanced cancer cell killing mediated by CD8+ T cells. Genetic depletion or pharmacologic inhibition of PIKfyve elevated tumor-specific MHC-I surface expression, increased intratumoral functional CD8+ T cells, and slowed tumor progression in multiple syngeneic mouse models. Importantly, enhanced antitumor responses by Pikfyve-depletion were CD8+ T cell- and MHC-I-dependent, as CD8+ T cell depletion or B2m knockout rescued tumor growth. Furthermore, PIKfyve inhibition improved response to immune checkpoint blockade (ICB), adoptive cell therapy, and a therapeutic vaccine. High expression of PIKFYVE was also predictive of poor response to ICB and prognostic of poor survival in ICB-treated cohorts. Collectively, our findings show that targeting PIKfyve enhances immunotherapies by elevating surface expression of MHC-I in cancer cells, and PIKfyve inhibitors have potential as agents to increase immunotherapy response in cancer patients.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias , Camundongos , Animais , Humanos , Genes MHC Classe I , Antígenos de Histocompatibilidade Classe I , Imunoterapia/métodos , Lipídeos , Neoplasias/genética , Neoplasias/terapia
5.
J Biol Chem ; : 107832, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39342998

RESUMO

Polyamines are polycationic molecules that are crucial in a wide array of cellular functions. Their biosynthesis is mediated by aminopropyl transferases (APTs), which are promising targets for antimicrobial, antineoplastic and antineurodegenerative therapies. A major limitation in studying APT enzymes, however, is the lack of high-throughput assays to measure their activity. We have developed the first fluorescence-based assay, DAB-APT, for the measurement of APT activity using 1,2-diacetyl benzene (DAB), which forms fluorescent conjugates with putrescine, spermidine, and spermine, with fluorescence intensity increasing with the carbon chain length. The assay has been validated using APT enzymes from Saccharomyces cerevisiae and Plasmodium falciparum, and the data further validated by mass spectrometry and thin-layer chromatography. Using mass spectrometry analysis, the structures of the fluorescent putrescine, spermidine and spermine 1,2-DAB adducts were determined to be substituted 1,3-dimethyl isoindoles. The DAB-APT assay is optimized for high-throughput screening, facilitating the evaluation of large chemical libraries. Given the critical roles of APTs in infectious diseases, oncology, and neurobiology, the DAB-APT assay offers a powerful tool with broad applicability, poised to drive advancements in research and drug discovery.

6.
N Engl J Med ; 387(10): 905-915, 2022 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-36036496

RESUMO

BACKGROUND: There are limited data from randomized trials to guide a specific follow-up surveillance approach after myocardial revascularization. Whether a follow-up strategy that includes routine functional testing improves clinical outcomes among high-risk patients who have undergone percutaneous coronary intervention (PCI) is uncertain. METHODS: We randomly assigned 1706 patients with high-risk anatomical or clinical characteristics who had undergone PCI to a follow-up strategy of routine functional testing (nuclear stress testing, exercise electrocardiography, or stress echocardiography) at 1 year after PCI or to standard care alone. The primary outcome was a composite of death from any cause, myocardial infarction, or hospitalization for unstable angina at 2 years. Key secondary outcomes included invasive coronary angiography and repeat revascularization. RESULTS: The mean age of the patients was 64.7 years, 21.0% had left main disease, 43.5% had bifurcation disease, 69.8% had multivessel disease, 70.1% had diffuse long lesions, 38.7% had diabetes, and 96.4% had been treated with drug-eluting stents. At 2 years, a primary-outcome event had occurred in 46 of 849 patients (Kaplan-Meier estimate, 5.5%) in the functional-testing group and in 51 of 857 (Kaplan-Meier estimate, 6.0%) in the standard-care group (hazard ratio, 0.90; 95% confidence interval [CI], 0.61 to 1.35; P = 0.62). There were no between-group differences with respect to the components of the primary outcome. At 2 years, 12.3% of the patients in the functional-testing group and 9.3% in the standard-care group had undergone invasive coronary angiography (difference, 2.99 percentage points; 95% CI, -0.01 to 5.99), and 8.1% and 5.8% of patients, respectively, had undergone repeat revascularization (difference, 2.23 percentage points; 95% CI, -0.22 to 4.68). CONCLUSIONS: Among high-risk patients who had undergone PCI, a follow-up strategy of routine functional testing, as compared with standard care alone, did not improve clinical outcomes at 2 years. (Funded by the CardioVascular Research Foundation and Daewoong Pharmaceutical; POST-PCI ClinicalTrials.gov number, NCT03217877.).


Assuntos
Doença da Artéria Coronariana , Stents Farmacológicos , Intervenção Coronária Percutânea , Assistência ao Convalescente , Ponte de Artéria Coronária/efeitos adversos , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Testes Diagnósticos de Rotina , Stents Farmacológicos/efeitos adversos , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Padrão de Cuidado , Resultado do Tratamento
7.
Circ Res ; 132(1): 52-71, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36448450

RESUMO

BACKGROUND: The osteochondrogenic switch of vascular smooth muscle cells (VSMCs) is a pivotal cellular process in atherosclerotic calcification. However, the exact molecular mechanism of the osteochondrogenic transition of VSMCs remains to be elucidated. Here, we explore the regulatory role of TXNIP (thioredoxin-interacting protein) in the phenotypical transitioning of VSMCs toward osteochondrogenic cells responsible for atherosclerotic calcification. METHODS: The atherosclerotic phenotypes of Txnip-/- mice were analyzed in combination with single-cell RNA-sequencing. The atherosclerotic phenotypes of Tagln-Cre; Txnipflox/flox mice (smooth muscle cell-specific Txnip ablation model), and the mice transplanted with the bone marrow of Txnip-/- mice were analyzed. Public single-cell RNA-sequencing dataset (GSE159677) was reanalyzed to define the gene expression of TXNIP in human calcified atherosclerotic plaques. The effect of TXNIP suppression on the osteochondrogenic phenotypic changes in primary aortic VSMCs was analyzed. RESULTS: Atherosclerotic lesions of Txnip-/- mice presented significantly increased calcification and deposition of collagen content. Subsequent single-cell RNA-sequencing analysis identified the modulated VSMC and osteochondrogenic clusters, which were VSMC-derived populations. The osteochondrogenic cluster was markedly expanded in Txnip-/- mice. The pathway analysis of the VSMC-derived cells revealed enrichment of bone- and cartilage-formation-related pathways and bone morphogenetic protein signaling in Txnip-/- mice. Reanalyzing public single-cell RNA-sequencing dataset revealed that TXNIP was downregulated in the modulated VSMC and osteochondrogenic clusters of human calcified atherosclerotic lesions. Tagln-Cre; Txnipflox/flox mice recapitulated the calcification and collagen-rich atherosclerotic phenotypes of Txnip-/- mice, whereas the hematopoietic deficiency of TXNIP did not affect the lesion phenotype. Suppression of TXNIP in cultured VSMCs accelerates osteodifferentiation and upregulates bone morphogenetic protein signaling. Treatment with the bone morphogenetic protein signaling inhibitor K02288 abrogated the effect of TXNIP suppression on osteodifferentiation. CONCLUSIONS: Our results suggest that TXNIP is a novel regulator of atherosclerotic calcification by suppressing bone morphogenetic protein signaling to inhibit the transition of VSMCs toward an osteochondrogenic phenotype.


Assuntos
Aterosclerose , Calcinose , Placa Aterosclerótica , Calcificação Vascular , Camundongos , Humanos , Animais , Músculo Liso Vascular/metabolismo , Células Cultivadas , Aterosclerose/metabolismo , Placa Aterosclerótica/patologia , Calcinose/metabolismo , Proteínas Morfogenéticas Ósseas/metabolismo , Miócitos de Músculo Liso/metabolismo , RNA/metabolismo , Calcificação Vascular/genética , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Tiorredoxinas/metabolismo
8.
Cell ; 143(3): 416-29, 2010 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-21029863

RESUMO

Dendritic cells (DCs), critical antigen-presenting cells for immune control, normally derive from bone marrow precursors distinct from monocytes. It is not yet established if the large reservoir of monocytes can develop into cells with critical features of DCs in vivo. We now show that fully differentiated monocyte-derived DCs (Mo-DCs) develop in mice and DC-SIGN/CD209a marks the cells. Mo-DCs are recruited from blood monocytes into lymph nodes by lipopolysaccharide and live or dead gram-negative bacteria. Mobilization requires TLR4 and its CD14 coreceptor and Trif. When tested for antigen-presenting function, Mo-DCs are as active as classical DCs, including cross-presentation of proteins and live gram-negative bacteria on MHC I in vivo. Fully differentiated Mo-DCs acquire DC morphology and localize to T cell areas via L-selectin and CCR7. Thus the blood monocyte reservoir becomes the dominant presenting cell in response to select microbes, yielding DC-SIGN(+) cells with critical functions of DCs.


Assuntos
Moléculas de Adesão Celular/metabolismo , Diferenciação Celular , Células Dendríticas/citologia , Escherichia coli/imunologia , Lectinas Tipo C/metabolismo , Monócitos/citologia , Receptores de Superfície Celular/metabolismo , Animais , Apresentação de Antígeno , Moléculas de Adesão Celular/imunologia , Células Dendríticas/imunologia , Selectina L/imunologia , Lectinas Tipo C/imunologia , Receptores de Lipopolissacarídeos/imunologia , Linfonodos/citologia , Linfonodos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Monócitos/imunologia , Receptores CCR7/imunologia , Receptores de Superfície Celular/imunologia , Linfócitos T/imunologia , Receptor 4 Toll-Like/agonistas , Receptor 4 Toll-Like/imunologia
9.
Nature ; 569(7755): 270-274, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31043744

RESUMO

Cancer immunotherapy restores or enhances the effector function of CD8+ T cells in the tumour microenvironment1,2. CD8+ T cells activated by cancer immunotherapy clear tumours mainly by inducing cell death through perforin-granzyme and Fas-Fas ligand pathways3,4. Ferroptosis is a form of cell death that differs from apoptosis and results from iron-dependent accumulation of lipid peroxide5,6. Although it has been investigated in vitro7,8, there is emerging evidence that ferroptosis might be implicated in a variety of pathological scenarios9,10. It is unclear whether, and how, ferroptosis is involved in T cell immunity and cancer immunotherapy. Here we show that immunotherapy-activated CD8+ T cells enhance ferroptosis-specific lipid peroxidation in tumour cells, and that increased ferroptosis contributes to the anti-tumour efficacy of immunotherapy. Mechanistically, interferon gamma (IFNγ) released from CD8+ T cells downregulates the expression of SLC3A2 and SLC7A11, two subunits of the glutamate-cystine antiporter system xc-, impairs the uptake of cystine by tumour cells, and as a consequence, promotes tumour cell lipid peroxidation and ferroptosis. In mouse models, depletion of cystine or cysteine by cyst(e)inase (an engineered enzyme that degrades both cystine and cysteine) in combination with checkpoint blockade synergistically enhanced T cell-mediated anti-tumour immunity and induced ferroptosis in tumour cells. Expression of system xc- was negatively associated, in cancer patients, with CD8+ T cell signature, IFNγ expression, and patient outcome. Analyses of human transcriptomes before and during nivolumab therapy revealed that clinical benefits correlate with reduced expression of SLC3A2 and increased IFNγ and CD8. Thus, T cell-promoted tumour ferroptosis is an anti-tumour mechanism, and targeting this pathway in combination with checkpoint blockade is a potential therapeutic approach.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Ferroptose , Imunoterapia , Neoplasias/imunologia , Neoplasias/terapia , Sistema y+ de Transporte de Aminoácidos/metabolismo , Animais , Antígeno B7-H1/antagonistas & inibidores , Linhagem Celular Tumoral , Cisteína/metabolismo , Feminino , Ferroptose/efeitos dos fármacos , Cadeia Pesada da Proteína-1 Reguladora de Fusão/metabolismo , Humanos , Interferon gama/imunologia , Peroxidação de Lipídeos , Melanoma/genética , Melanoma/imunologia , Melanoma/metabolismo , Melanoma/terapia , Camundongos , Neoplasias/metabolismo , Nivolumabe/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Resultado do Tratamento
10.
Eur Heart J ; 45(9): 653-665, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37933514

RESUMO

BACKGROUND AND AIMS: The optimal follow-up surveillance strategy for high-risk diabetic patients with had undergone percutaneous coronary intervention (PCI) remains unknown. METHODS: The POST-PCI (Pragmatic Trial Comparing Symptom-Oriented versus Routine Stress Testing in High-Risk Patients Undergoing Percutaneous Coronary Intervention) study was a randomized trial comparing a follow-up strategy of routine functional testing at 1 year vs. standard care alone after high-risk PCI. Randomization was stratified according to diabetes status. The primary outcome was a composite of death from any cause, myocardial infarction, or hospitalization for unstable angina at 2 years. RESULTS: Among 1706 randomized patients, participants with diabetes (n = 660, 38.7%) had more frequent comorbidities and a higher prevalence of complex anatomical or procedural characteristics than those without diabetes (n = 1046, 61.3%). Patients with diabetes had a 52% greater risk of primary composite events [hazard ratio (HR) 1.52; 95% confidence interval (CI) 1.02-2.27; P = .039]. The 2-year incidences of the primary composite outcome were similar between strategies of routine functional testing or standard care alone in diabetic patients (7.1% vs. 7.5%; HR 0.94; 95% CI 0.53-1.66; P = .82) and non-diabetic patients (4.6% vs. 5.1%; HR 0.89; 95% CI 0.51-1.55; P = .68) (interaction term for diabetes: P = .91). The incidences of invasive coronary angiography and repeat revascularization after 1 year were higher in the routine functional-testing group than the standard-care group irrespective of diabetes status. CONCLUSIONS: Despite being at higher risk for adverse clinical events, patients with diabetes who had undergone high-risk PCI did not derive incremental benefit from routine surveillance stress testing compared with standard care alone during follow-up.


Assuntos
Diabetes Mellitus , Intervenção Coronária Percutânea , Humanos , Angina Instável/epidemiologia , Testes de Coagulação Sanguínea , Angiografia Coronária , Diabetes Mellitus/epidemiologia
11.
J Proteome Res ; 23(1): 142-148, 2024 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-38009700

RESUMO

Targeted proteomics strategies present a streamlined hypothesis-driven approach to analyze specific sets of pathways or disease related proteins. goDig is a quantitative, targeted tandem mass tag (TMT)-based assay that can measure the relative abundance differences for hundreds of proteins directly from unfractionated mixtures. Specific protein groups or entire pathways of up to 200 proteins can be selected for quantitative profiling, while leveraging sample multiplexing permits the simultaneous analysis of up to 18 samples. Despite these benefits, implementing goDig is not without challenges, as it requires access to an instrument application programming interface (iAPI), an elution order and spectral library, a web-based method builder, and dedicated companion software. In addition, the absence of an example test assay may dissuade researchers from testing or implementing goDig. Here, we repurpose the TKO11 standard─which is commercially available but may also be assembled in-lab─and establish it as a de facto test assay for goDig. We build a proteome-wide goDig yeast library, quantify protein expression across several gene ontology (GO) categories, and compare these results to a fully fractionated yeast gold-standard data set. Essentially, we provide a guide detailing the goDig-based quantification of TKO11, which can also be used as a template for user-defined assays in other species.


Assuntos
Saccharomyces cerevisiae , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Proteômica/métodos , Software , Proteoma/análise
12.
J Biol Chem ; 299(5): 104659, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36997087

RESUMO

Decarboxylation of phosphatidylserine (PS) to form phosphatidylethanolamine by PS decarboxylases (PSDs) is an essential process in most eukaryotes. Processing of a malarial PSD proenzyme into its active alpha and beta subunits is by an autoendoproteolytic mechanism regulated by anionic phospholipids, with PS serving as an activator and phosphatidylglycerol (PG), phosphatidylinositol, and phosphatidic acid acting as inhibitors. The biophysical mechanism underlying this regulation remains unknown. We used solid phase lipid binding, liposome-binding assays, and surface plasmon resonance to examine the binding specificity of a processing-deficient Plasmodium PSD (PkPSDS308A) mutant enzyme and demonstrated that the PSD proenzyme binds strongly to PS and PG but not to phosphatidylethanolamine and phosphatidylcholine. The equilibrium dissociation constants (Kd) of PkPSD with PS and PG were 80.4 nM and 66.4 nM, respectively. The interaction of PSD with PS is inhibited by calcium, suggesting that the binding mechanism involves ionic interactions. In vitro processing of WT PkPSD proenzyme was also inhibited by calcium, consistent with the conclusion that PS binding to PkPSD through ionic interactions is required for the proenzyme processing. Peptide mapping identified polybasic amino acid motifs in the proenzyme responsible for binding to PS. Altogether, the data demonstrate that malarial PSD maturation is regulated through a strong physical association between PkPSD proenzyme and anionic lipids. Inhibition of the specific interaction between the proenzyme and the lipids can provide a novel mechanism to disrupt PSD enzyme activity, which has been suggested as a target for antimicrobials, and anticancer therapies.


Assuntos
Carboxiliases , Malária , Fosfolipídeos , Plasmodium , Motivos de Aminoácidos , Cálcio/metabolismo , Cálcio/farmacologia , Carboxiliases/antagonistas & inibidores , Carboxiliases/química , Carboxiliases/metabolismo , Precursores Enzimáticos/metabolismo , Lipossomos , Ácidos Fosfatídicos/metabolismo , Ácidos Fosfatídicos/farmacologia , Fosfatidilcolinas/metabolismo , Fosfatidilcolinas/farmacologia , Fosfatidiletanolaminas/metabolismo , Fosfatidiletanolaminas/farmacologia , Fosfatidilgliceróis/metabolismo , Fosfatidilgliceróis/farmacologia , Fosfatidilinositóis/metabolismo , Fosfatidilinositóis/farmacologia , Fosfatidilserinas/metabolismo , Fosfatidilserinas/farmacologia , Fosfolipídeos/química , Fosfolipídeos/metabolismo , Fosfolipídeos/farmacologia , Ligação Proteica , Malária/parasitologia , Proteólise/efeitos dos fármacos , Ressonância de Plasmônio de Superfície , Plasmodium/enzimologia
13.
J Biol Chem ; 299(11): 105313, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37797695

RESUMO

Effective and safe therapies for the treatment of diseases caused by intraerythrocytic parasites are impeded by the rapid emergence of drug resistance and the lack of novel drug targets. One such disease is human babesiosis, which is a rapidly emerging tick-borne illness caused by Babesia parasites. In this study, we identified fosinopril, a phosphonate-containing, FDA-approved angiotensin converting enzyme (ACE) inhibitor commonly used as a prodrug for hypertension and heart failure, as a potent inhibitor of Babesia duncani parasite development within human erythrocytes. Cell biological and mass spectrometry analyses revealed that the conversion of fosinopril to its active diacid molecule, fosinoprilat, is essential for its antiparasitic activity. We show that this conversion is mediated by a parasite-encoded esterase, BdFE1, which is highly conserved among apicomplexan parasites. Parasites carrying the L238H mutation in the active site of BdFE1 failed to convert the prodrug to its active moiety and became resistant to the drug. Our data set the stage for the development of this class of drugs for the therapy of vector-borne parasitic diseases.


Assuntos
Babesia , Parasitos , Pró-Fármacos , Animais , Humanos , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Fosinopril/farmacologia , Pró-Fármacos/farmacologia , Esterases/metabolismo
14.
J Am Chem Soc ; 2024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-39412402

RESUMO

On the basis of a streamlined route to the pyrroloiminoquinone (PIQ) core, we made 16 natural products spread across four classes of biosynthetically related alkaloid natural products, and multiple structural analogs, all in ≤8 steps longest linear sequence (LLS). The strategy features a Larock indole synthesis as the key operation in a five-step synthesis of a key methoxy-PIQ intermediate. Critically, this compound was readily diverged via selective methylation of either (or both) of the imine-like or pyrrole nitrogens, which then permitted further divergence by either O-demethylation to o-quinone natural products or displacement of the methoxy group with a range of amine nucleophiles. Based on a single, early report of their potential utility against the malaria parasite, we assayed these compounds against several strains of Plasmodium falciparum, as well as two species of the related protozoan parasite Babesia. In combination with evaluations of their human cytotoxicity, we identified several compounds with potent (low-nM IC50) antimalarial and antibabesial activities that are much less toxic toward mammalian cells and are therefore promising lead compounds for antiprotozoal drug discovery.

15.
J Intern Med ; 2024 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-39370680

RESUMO

BACKGROUND: Limited evidence exists on the role of depression in the risk of developing stroke and other cardiovascular outcomes in patients who have undergone percutaneous coronary interventions (PCI). We investigated this relationship with data from the Korean National Health Insurance Service database. METHODS: Our nationwide retrospective cohort study included 164,198 patients who had undergone PCI between 2010 and 2017. Depression was defined with the ICD-10 codes recorded prior to the PCI. The primary outcome was a new-onset stroke following the PCI. Secondary outcomes included PCI with myocardial infarction (MI), revascularization (PCI or coronary artery bypass grafting), and all-cause mortality. A multivariable Cox proportional hazards regression analysis was used to calculate adjusted hazard ratios (aHR) and 95% confidence intervals (CI), adjusting for potential confounders, including sociodemographic and lifestyle factors, comorbidities, and MI at the index PCI. RESULTS: Over a median follow-up of 5.0 years, acute stroke occurred in 5.7% of patients with pre-existing depression (17.4% of the study population), compared to 3.5% of those without depression. Depression was associated with a 27% increased risk of acute stroke (aHR 1.27, 95% CI 1.20-1.35). Additionally, depression was linked with a 25% elevated risk of all-cause death (aHR 1.25, 95% CI, 1.21-1.29) and an 8% increased risk of revascularization (aHR 1.08, 95% CI 1.04-1.11). The associations with the risk of stroke and all-cause mortality were stronger in patients under 65 years. CONCLUSIONS: Our findings suggest that pre-existing depression may increase the risk of stroke and all-cause mortality following PCI, particularly in patients under 65 years. Additionally, depression was significantly associated with an increased need for revascularization. This underscores the potential benefits of managing depression to reduce stroke risk and overall cardiovascular outcomes following PCI.

16.
Small ; 20(30): e2400828, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38693068

RESUMO

Efficient support materials are crucial for maximizing the efficacy of nanomaterials in various applications such as energy storage, drug delivery, catalysis, and environmental remediation. However, traditional supports often hinder nanomaterial performance due to their high weight ratio and limited manageability, leading to issues like tube blocking and secondary pollution. To address this, a novel grapefruit-inspired polymeric capsule (GPC) as a promising carrier platform is introduced. The millimeter-scale GPC features a hydrophilic shell and an internal hierarchical microstructure with 80% void volume, providing ample space for encapsulating diverse nanomaterials including metals, polymers, metal-organic frameworks, and silica. Through liquid-phase bottom-up methods, it is successfully loaded Fe2O3, SiO2, polyacrylic acid, and Prussian blue nanomaterials onto the GPC, achieving high mass ratio (1776, 488, 898, and 634 wt.%, respectively). The GPC shell prevents nanomaterial leakage and the influx of suspended solids, while its internal framework enhances structural stability and mass transfer rates. With long-term storage stability, high carrying capacity, and versatile applicability, the GPC significantly enhances the field applicability of nanomaterials.

17.
Small ; : e2404343, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39058242

RESUMO

1D nanostructures exhibit a large surface area and a short network distance, facilitating electron and ion transport. In this study, a 1D van der Waals material, tin iodide phosphide (SnIP), is synthesized and used as an electrocatalyst for the conversion of CO2 to formate. The electrochemical treatment of SnIP reconstructs it into a web-like structure, dissolves the I and P components, and increases the number of oxygen vacancies. The resulting oxygen vacancies promote the activity of the CO2 reduction reaction (CO2RR), increasing the local pH of the electrode surface and maintaining the oxidative metal site of the catalyst despite the electrochemically reducing environment. This strategy, which stabilizes the oxidation state of the catalyst, also helps to improve the durability of CO2RR. In practice, 1D structured SnIP catalyst exhibits outstanding performance with >92% formate faradaic efficiency (FEformate) at 300 mA cm-2, a maximum partial current density for formate of 343 mA cm-2, and excellent long-term stability (>100 h at 100 mA cm-2 with >86% FEformate). This study introduced a method to easily generate oxygen vacancies on the catalyst surface by utilizing 1D materials and a strategy to improve the durability of CO2RR by stabilizing the oxidation state of the catalyst.

18.
Invest New Drugs ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39227508

RESUMO

ESK981 is a potent tyrosine kinase and PIKfyve lipid kinase inhibitor. This phase II trial evaluated the efficacy of ESK981 as a single agent in patients with androgen receptor-positive (AR +) metastatic castration-resistant prostate cancer (mCRPC). Eligible patients had mCRPC with progression on AR-targeted agents and without prior chemotherapy treatment. Each patient received 160 mg ESK981 once daily for 5 days per week for 4 weeks per cycle (except for an adverse event (AE) occurrence). The primary endpoints were a 50% reduction in prostate-specific antigen (PSA50), and safety. Secondary endpoints included the time and the duration of PSA response, PSA progression rates, PSA progression free survival (PFS) and overall survival (OS). Exploratory investigations included whole exome sequencing in patients before treatment, and morphological evaluation of biopsy samples pre- and post-treatment. PSA was evaluated in 13 patients. Only one patient (7.7% two-sided 95% Wilson CI (0.4%, 33.3%)) experienced a reduction in their PSA levels by 50% or more. The most common grade 3 treatment-related AEs were cardiac disorders, diarrhea, hypertension, alanine transaminase and aspartate transaminase elevations. No grade 4-5 events occurred. Median PFS was 1.8 months, and median OS was 12.1 months. Peripheral immune cells showed increased T cell activation and cytokine production in two patients who received 12-weeks of ESK981. Although relatively well tolerated, ESK981 alone showed no anti-tumor activity in patients with AR + mCRPC and its further evaluation as a single agent in AR + mCRPC is not warranted. (Trial registration: ClinicalTrials.gov, NCT03456804. Registration date: March 7, 2018).

19.
Plant Cell ; 33(4): 1118-1134, 2021 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-33580702

RESUMO

Telomeres are highly repetitive DNA sequences found at the ends of chromosomes that protect the chromosomes from deterioration duringcell division. Here, using whole-genome re-sequencing and terminal restriction fragment assays, we found substantial natural intraspecific variation in telomere length in Arabidopsis thaliana, rice (Oryza sativa), and maize (Zea mays). Genome-wide association study (GWAS) mapping in A. thaliana identified 13 regions with GWAS-significant associations underlying telomere length variation, including a region that harbors the telomerase reverse transcriptase (TERT) gene. Population genomic analysis provided evidence for a selective sweep at the TERT region associated with longer telomeres. We found that telomere length is negatively correlated with flowering time variation not only in A. thaliana, but also in maize and rice, indicating a link between life-history traits and chromosome integrity. Our results point to several possible reasons for this correlation, including the possibility that longer telomeres may be more adaptive in plants that have faster developmental rates (and therefore flower earlier). Our work suggests that chromosomal structure itself might be an adaptive trait associated with plant life-history strategies.


Assuntos
Flores/fisiologia , Variação Genética , Fenômenos Fisiológicos Vegetais/genética , Telômero/genética , Arabidopsis/genética , Tamanho do Genoma , Genoma de Planta , Estudo de Associação Genômica Ampla , Oryza/genética , Seleção Genética , Sequências de Repetição em Tandem , Telomerase/genética , Fatores de Tempo , Zea mays/genética
20.
Neuroepidemiology ; : 1-9, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38952140

RESUMO

BACKGROUND: Smoking is a well-known risk factor for cardiovascular diseases, including myocardial infarction (MI) and ischemic stroke (IS). While the relationship between smoking and the risk of cardiovascular diseases is established, the impact of changing smoking habits post-IS on the risk of subsequent MI remains unclear. This study aims to elucidate the effects of alterations in smoking behavior following an IS diagnosis on the likelihood of experiencing an MI. METHODS: Utilizing data from the Korean National Health Insurance Services Database, this nationwide population-based cohort study included 199,051 participants diagnosed with IS between January 2010 and December 2016. Smoking status was categorized based on changes in smoking habits before and after IS diagnosis. The association between changes in smoking behavior and the risk of subsequent MI was analyzed using multivariable Cox proportional hazard regression models. RESULTS: During a median follow-up of 4.17 person-years, a total of 5,734 (2.88%) patients were diagnosed with MI after IS. Smoking quitters (2.93%) or former smokers (2.47%) have a similar or lower rate of MI than the average, even if they have smoked cigarettes, while sustained smokers (3.46%) or new smokers (3.81%) have much higher rates of MI. Among sustained and new smokers, the risk of incident MI was significantly higher than never smokers (new smoker adjusted HR [aHR]: 1.496, 95% CI: 1.262-1.774; sustained smoker aHR: 1.494, 95% CI: 1.361-1.641). Also, among the study participants, approximately two-thirds continued smoking after their IS diagnosis. CONCLUSION: Changing smoking habits after an IS diagnosis significantly influences the risk of subsequent MI. Specifically, continuing or starting to smoke after an IS diagnosis is associated with a higher risk of MI. These results underscore the importance of targeted smoking cessation interventions for stroke patients to reduce the risk of subsequent MI.

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