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1.
Cell ; 170(5): 889-898.e10, 2017 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-28803729

RESUMO

Eukaryotic promoter regions are frequently divergently transcribed in vivo, but it is unknown whether the resultant antisense RNAs are a mechanistic by-product of RNA polymerase II (Pol II) transcription or biologically meaningful. Here, we use a functional evolutionary approach that involves nascent transcript mapping in S. cerevisiae strains containing foreign yeast DNA. Promoter regions in foreign environments lose the directionality they have in their native species. Strikingly, fortuitous promoter regions arising in foreign DNA produce equal transcription in both directions, indicating that divergent transcription is a mechanistic feature that does not imply a function for these transcripts. Fortuitous promoter regions arising during evolution promote bidirectional transcription and over time are purged through mutation or retained to enable new functionality. Similarly, human transcription is more bidirectional at newly evolved enhancers and promoter regions. Thus, promoter regions are intrinsically bidirectional and are shaped by evolution to bias transcription toward coding versus non-coding RNAs.


Assuntos
Evolução Molecular , Regiões Promotoras Genéticas , Saccharomyces cerevisiae/genética , Saccharomycetales/genética , Transcrição Gênica , Elementos Facilitadores Genéticos , Humanos , RNA Polimerase II/metabolismo , Saccharomyces cerevisiae/metabolismo , Saccharomycetales/classificação
2.
Plant Cell ; 36(2): 298-323, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37847093

RESUMO

The high-yielding Green Revolution varieties of cereal crops are characterized by a semidwarf architecture and lodging resistance. Plant height is tightly regulated by the availability of phosphate (Pi), yet the underlying mechanism remains obscure. Here, we report that rice (Oryza sativa) R2R3-type Myeloblastosis (MYB) transcription factor MYB110 is a Pi-dependent negative regulator of plant height. MYB110 is a direct target of PHOSPHATE STARVATION RESPONSE 2 (OsPHR2) and regulates OsPHR2-mediated inhibition of rice height. Inactivation of MYB110 increased culm diameter and bending resistance, leading to enhanced lodging resistance despite increased plant height. Strikingly, the grain yield of myb110 mutants was elevated under both high- and low-Pi regimes. Two divergent haplotypes based on single nucleotide polymorphisms in the putative promoter of MYB110 corresponded with its transcript levels and plant height in response to Pi availability. Thus, fine-tuning MYB110 expression may be a potent strategy for further increasing the yield of Green Revolution cereal crop varieties.


Assuntos
Grão Comestível , Oryza , Grão Comestível/genética , Oryza/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Produtos Agrícolas , Fosfatos/metabolismo
3.
Immunity ; 46(5): 818-834.e4, 2017 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-28514688

RESUMO

Innate and adaptive lymphoid development is orchestrated by the activities of E proteins and their antagonist Id proteins, but how these factors regulate early T cell progenitor (ETP) and innate lymphoid cell (ILC) development remains unclear. Using multiple genetic strategies, we demonstrated that E proteins E2A and HEB acted in synergy in the thymus to establish T cell identity and to suppress the aberrant development of ILCs, including ILC2s and lymphoid-tissue-inducer-like cells. E2A and HEB orchestrated T cell fate and suppressed the ILC transcription signature by activating the expression of genes associated with Notch receptors, T cell receptor (TCR) assembly, and TCR-mediated signaling. E2A and HEB acted in ETPs to establish and maintain a T-cell-lineage-specific enhancer repertoire, including regulatory elements associated with the Notch1, Rag1, and Rag2 loci. On the basis of these and previous observations, we propose that the E-Id protein axis specifies innate and adaptive lymphoid cell fate.


Assuntos
Imunidade Adaptativa , Imunidade Inata , Imunomodulação , Subpopulações de Linfócitos/imunologia , Timócitos/imunologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Diferenciação Celular/imunologia , Análise por Conglomerados , Expressão Gênica , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Imunofenotipagem , Proteína 2 Inibidora de Diferenciação/genética , Proteína 2 Inibidora de Diferenciação/metabolismo , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Subpopulações de Linfócitos/citologia , Subpopulações de Linfócitos/metabolismo , Células Progenitoras Linfoides/metabolismo , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Fenótipo , Especificidade do Receptor de Antígeno de Linfócitos T/imunologia , Timócitos/citologia , Timócitos/metabolismo , Transcriptoma
4.
Proc Natl Acad Sci U S A ; 120(51): e2304213120, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38085773

RESUMO

The disequilibrium of amyloid ß-peptide (Aß) between the central and peripheral pools has been claimed as an initiating event in Alzheimer's disease (AD). In this study, we employ discoidal high-density lipoproteins (HDL-Disc) mimicking Aß antibody for directional flux of Aß from central to peripheral catabolism, with desirable safety and translation potential. Structurally, HDL-Disc assembly (polyDisc) is prepared with aid of chitosan derivative polymerization. After intranasal administration and response to slightly acidic nasal microenvironment, polyDisc depolymerizes into carrier-free HDL-Disc with chitosan derivatives that adhere to the mucosal layer to reversibly open tight junctions, helping HDL-Disc penetrate the olfactory pathway into brain. Thereafter, HDL-Disc captures Aß into microglia for central clearance or ferries Aß out of the brain for liver-mediated compensatory catabolism. For synergy therapy, intranasal administration of polyDisc can effectively reduce intracerebral Aß burden by 97.3% and vascular Aß burden by 73.5%, ameliorate neurologic damage, and rescue memory deficits in APPswe/PS1dE9 transgenic AD mice with improved safety, especially vascular safety. Collectively, this design provides a proof of concept for developing Aß antibody mimics to mobilize a synergy of central and peripheral Aß clearance for AD treatment.


Assuntos
Doença de Alzheimer , Quitosana , Camundongos , Animais , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Quitosana/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Encéfalo/metabolismo , Camundongos Transgênicos , Modelos Animais de Doenças
5.
J Immunol ; 210(8): 1134-1145, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36881871

RESUMO

Solid-organ transplant recipients exhibiting HLA donor-specific Abs are at risk for graft loss due to chronic Ab-mediated rejection. HLA Abs bind HLA molecules expressed on the surface of endothelial cells (ECs) and induce intracellular signaling pathways, including the activation of the transcriptional coactivator yes-associated protein (YAP). In this study, we examined the impact of lipid-lowering drugs of the statin family on YAP localization, multisite phosphorylation, and transcriptional activity in human ECs. Exposure of sparse cultures of ECs to cerivastatin or simvastatin induced striking relocalization of YAP from the nucleus to the cytoplasm and inhibited the expression of the YAP/TEA domain DNA-binding transcription factor-regulated genes connective tissue growth factor and cysteine-rich angiogenic inducer 61. In dense cultures of ECs, statins prevented YAP nuclear import and expression of connective tissue growth factor and cysteine-rich angiogenic inducer 61 stimulated by the mAb W6/32 that binds HLA class I. Exposure of ECs to either cerivastatin or simvastatin completely blocked the migration of ECs stimulated by ligation of HLA class I. Exogenously supplied mevalonic acid or geranylgeraniol reversed the inhibitory effects of statins on YAP localization either in low-density ECs or high-density ECs challenged with W6/32. Mechanistically, cerivastatin increased the phosphorylation of YAP at Ser127, blunted the assembly of actin stress fiber, and inhibited YAP phosphorylation at Tyr357 in ECs. Using mutant YAP, we substantiated that YAP phosphorylation at Tyr357 is critical for YAP activation. Collectively, our results indicate that statins restrain YAP activity in EC models, thus providing a plausible mechanism underlying their beneficial effects in solid-organ transplant recipients.


Assuntos
Células Endoteliais , Inibidores de Hidroximetilglutaril-CoA Redutases , Proteínas de Sinalização YAP , Humanos , Fator de Crescimento do Tecido Conjuntivo/genética , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Cisteína/metabolismo , Células Endoteliais/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Fosforilação , Sinvastatina/farmacologia , Genes MHC Classe I , Proteínas de Sinalização YAP/genética
6.
Gut ; 73(7): 1183-1198, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38621924

RESUMO

OBJECTIVE: Targeting bacterial translocation in cirrhosis is limited to antibiotics with risk of antimicrobial resistance. This study explored the therapeutic potential of a non-absorbable, gut-restricted, engineered carbon bead adsorbent, Yaq-001 in models of cirrhosis and acute-on-chronic liver failure (ACLF) and, its safety and tolerability in a clinical trial in cirrhosis. DESIGN: Performance of Yaq-001 was evaluated in vitro. Two-rat models of cirrhosis and ACLF, (4 weeks, bile duct ligation with or without lipopolysaccharide), receiving Yaq-001 for 2 weeks; and two-mouse models of cirrhosis (6-week and 12-week carbon tetrachloride (CCl4)) receiving Yaq-001 for 6 weeks were studied. Organ and immune function, gut permeability, transcriptomics, microbiome composition and metabolomics were analysed. The effect of faecal water on gut permeability from animal models was evaluated on intestinal organoids. A multicentre, double-blind, randomised, placebo-controlled clinical trial in 28 patients with cirrhosis, administered 4 gr/day Yaq-001 for 3 months was performed. RESULTS: Yaq-001 exhibited rapid adsorption kinetics for endotoxin. In vivo, Yaq-001 reduced liver injury, progression of fibrosis, portal hypertension, renal dysfunction and mortality of ACLF animals significantly. Significant impact on severity of endotoxaemia, hyperammonaemia, liver cell death, systemic inflammation and organ transcriptomics with variable modulation of inflammation, cell death and senescence in the liver, kidneys, brain and colon was observed. Yaq-001 reduced gut permeability in the organoids and impacted positively on the microbiome composition and metabolism. Yaq-001 regulated as a device met its primary endpoint of safety and tolerability in the clinical trial. CONCLUSIONS: This study provides strong preclinical rationale and safety in patients with cirrhosis to allow clinical translation. TRIAL REGISTRATION NUMBER: NCT03202498.


Assuntos
Insuficiência Hepática Crônica Agudizada , Microbioma Gastrointestinal , Cirrose Hepática , Humanos , Animais , Cirrose Hepática/complicações , Camundongos , Masculino , Microbioma Gastrointestinal/efeitos dos fármacos , Método Duplo-Cego , Ratos , Modelos Animais de Doenças , Feminino , Pessoa de Meia-Idade , Translocação Bacteriana/efeitos dos fármacos , Carbono/uso terapêutico , Carbono/farmacologia
7.
Am J Transplant ; 24(3): 406-418, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38379280

RESUMO

HLA donor-specific antibodies (DSA) elicit alloimmune responses against the graft vasculature, leading to endothelial cell (EC) activation and monocyte infiltration during antibody-mediated rejection (AMR). AMR promotes chronic inflammation and remodeling, leading to thickening of the arterial intima termed transplant vasculopathy or cardiac allograft vasculopathy (CAV) in heart transplants. Intragraft-recipient macrophages serve as a diagnostic marker in AMR; however, their polarization and function remain unclear. In this study, we utilized an in vitro Transwell coculture system to explore the mechanisms of monocyte-to-macrophage polarization induced by HLA I DSA-activated ECs. Anti-HLA I (IgG or F(ab')2) antibody-activated ECs induced the polarization of M2 macrophages with increased CD206 expression and MMP9 secretion. However, inhibition of TLR4 signaling or PSGL-1-P-selectin interactions significantly decreased both CD206 and MMP9. Monocyte adherence to Fc-P-selectin coated plates induced M2 macrophages with increased CD206 and MMP9. Moreover, Fc-receptor and IgG interactions synergistically enhanced active-MMP9 in conjunction with P-selectin. Transcriptomic analysis of arteries from DSA+CAV+ rejected cardiac allografts and multiplex-immunofluorescent staining illustrated the expression of CD68+CD206+CD163+MMP9+ M2 macrophages within the neointima of CAV-affected lesions. These findings reveal a novel mechanism linking HLA I antibody-activated endothelium to the generation of M2 macrophages which secrete vascular remodeling proteins contributing to AMR and CAV pathogenesis.


Assuntos
Receptor 4 Toll-Like , Doenças Vasculares , Humanos , Metaloproteinase 9 da Matriz , Selectina-P , Macrófagos , Endotélio , Antígenos HLA , Aloenxertos , Imunoglobulina G
8.
Antimicrob Agents Chemother ; 68(1): e0133023, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38054726

RESUMO

FL058 is a novel diazabicyclooctane ß-lactamase inhibitor. This first-in-human study evaluated the safety, tolerability, and population pharmacokinetic (PK)/pharmacodynamic target attainment analysis of FL058 alone and in combination with meropenem in healthy subjects. The results showed that the maximum tolerated dose of FL058 was 3,000 mg after single-dose infusion. FL058 in combination with meropenem did not cause any grade 3 or higher adverse event when the dose was escalated up to 1,000 mg/2,000 mg. FL058 exposure PK parameters showed dose proportionality. FL058 was excreted primarily in urine. No significant PK interaction was found between FL058 and meropenem. Population PK model analysis indicated that the PK profiles of FL058 and meropenem were consistent with the two-compartment model. The impact of covariates, creatinine clearance, concomitant use of meropenem, body weight, sex, and FL058 dose, on FL058 exposure was less than 10%. FL058/meropenem combination was safe and well tolerated up to a 1,000-mg/2,000-mg dose in healthy adults. The recommended minimum dose of FL058/meropenem combination was 500 mg/1,000 mg by intravenous infusion over 2 h every 8 h based on target attainment analysis. The good safety, tolerability, and satisfactory PK profiles of FL058 alone and in combination with meropenem in this first-in-human study will support further clinical development of FL058 in combination with meropenem in patients with target infections (ClinicalTrials.gov identifiers: NCT05055687, NCT05058118, and NCT05058105).


Assuntos
Antibacterianos , Inibidores de beta-Lactamases , Adulto , Humanos , Meropeném/farmacologia , Antibacterianos/farmacocinética , Voluntários Saudáveis , Inibidores de beta-Lactamases/efeitos adversos , Infusões Intravenosas
9.
J Transl Med ; 22(1): 6, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167440

RESUMO

BACKGROUND: Tandem C2 domains, nuclear (TC2N) is a C2 domain-containing protein that belongs to the carboxyl-terminal type (C-type) tandem C2 protein family, and acts as an oncogenic driver in several cancers. Previously, we preliminarily reported that TC2N mediates the PI3K-Akt signaling pathway to inhibit tumor growth of breast cancer (BC) cells. Beyond that, its precise biological functions and detailed molecular mechanisms in BC development and progression are not fully understood. METHODS: Tumor tissues of 212 BC patients were subjected to tissue microarray and further assessed the associations of TC2N expression with pathological parameters and FASN expression. The protein levels of TC2N and FASN in cell lines and tumor specimens were monitored by qRT-PCR, WB, immunofluorescence and immunohistochemistry. In vitro cell assays, in vivo nude mice model was used to assess the effect of TC2N ectopic expression on tumor metastasis and stemness of breast cancer cells. The downstream signaling pathway or target molecule of TC2N was mined using a combination of transcriptomics, proteomics and lipidomics, and the underlying mechanism was explored by WB and co-IP assays. RESULTS: Here, we found that the expression of TC2N remarkedly silenced in metastatic and poorly differentiated tumors. Function-wide, TC2N strongly inhibits tumor metastasis and stem-like properties of BC via inhibition of fatty acid synthesis. Mechanism-wise, TC2N blocks neddylated PTEN-mediated FASN stabilization by a dual mechanism. The C2B domain is crucial for nuclear localization of TC2N, further consolidating the TRIM21-mediated ubiquitylation and degradation of FASN by competing with neddylated PTEN for binding to FASN in nucleus. On the other hand, cytoplasmic TC2N interacts with import proteins, thereby restraining nuclear import of PTEN to decrease neddylated PTEN level. CONCLUSIONS: Altogether, we demonstrate a previously unidentified role and mechanism of TC2N in regulation of lipid metabolism and PTEN neddylation, providing a potential therapeutic target for anti-cancer.


Assuntos
Neoplasias da Mama , Animais , Camundongos , Humanos , Feminino , Neoplasias da Mama/patologia , Camundongos Nus , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Ácidos Graxos , Linhagem Celular Tumoral , Proteínas Proto-Oncogênicas c-akt/metabolismo , PTEN Fosfo-Hidrolase/genética , Proliferação de Células , Regulação Neoplásica da Expressão Gênica
10.
Cardiovasc Diabetol ; 23(1): 138, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664801

RESUMO

BACKGROUND: Neutral cholesterol ester hydrolase 1 (NCEH1) plays a critical role in the regulation of cholesterol ester metabolism. Deficiency of NCHE1 accelerated atherosclerotic lesion formation in mice. Nonetheless, the role of NCEH1 in endothelial dysfunction associated with diabetes has not been explored. The present study sought to investigate whether NCEH1 improved endothelial function in diabetes, and the underlying mechanisms were explored. METHODS: The expression and activity of NCEH1 were determined in obese mice with high-fat diet (HFD) feeding, high glucose (HG)-induced mouse aortae or primary endothelial cells (ECs). Endothelium-dependent relaxation (EDR) in aortae response to acetylcholine (Ach) was measured. RESULTS: Results showed that the expression and activity of NCEH1 were lower in HFD-induced mouse aortae, HG-exposed mouse aortae ex vivo, and HG-incubated primary ECs. HG exposure reduced EDR in mouse aortae, which was exaggerated by endothelial-specific deficiency of NCEH1, whereas NCEH1 overexpression restored the impaired EDR. Similar results were observed in HFD mice. Mechanically, NCEH1 ameliorated the disrupted EDR by dissociating endothelial nitric oxide synthase (eNOS) from caveolin-1 (Cav-1), leading to eNOS activation and nitric oxide (NO) release. Moreover, interaction of NCEH1 with the E3 ubiquitin-protein ligase ZNRF1 led to the degradation of Cav-1 through the ubiquitination pathway. Silencing Cav-1 and upregulating ZNRF1 were sufficient to improve EDR of diabetic aortas, while overexpression of Cav-1 and downregulation of ZNRF1 abolished the effects of NCEH1 on endothelial function in diabetes. Thus, NCEH1 preserves endothelial function through increasing NO bioavailability secondary to the disruption of the Cav-1/eNOS complex in the endothelium of diabetic mice, depending on ZNRF1-induced ubiquitination of Cav-1. CONCLUSIONS: NCEH1 may be a promising candidate for the prevention and treatment of vascular complications of diabetes.


Assuntos
Caveolina 1 , Dieta Hiperlipídica , Células Endoteliais , Endotélio Vascular , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo III , Vasodilatação , Animais , Masculino , Camundongos , Aorta/enzimologia , Aorta/fisiopatologia , Aorta/metabolismo , Aorta/efeitos dos fármacos , Aorta/patologia , Caveolina 1/metabolismo , Caveolina 1/deficiência , Caveolina 1/genética , Células Cultivadas , Diabetes Mellitus Experimental/enzimologia , Diabetes Mellitus Experimental/fisiopatologia , Células Endoteliais/enzimologia , Células Endoteliais/metabolismo , Células Endoteliais/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Endotélio Vascular/metabolismo , Endotélio Vascular/enzimologia , Endotélio Vascular/efeitos dos fármacos , Camundongos Knockout , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Obesidade/enzimologia , Obesidade/fisiopatologia , Obesidade/metabolismo , Transdução de Sinais , Esterol Esterase/metabolismo , Esterol Esterase/genética , Ubiquitinação , Vasodilatação/efeitos dos fármacos
11.
Diabetes Metab Res Rev ; 40(2): e3739, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37862117

RESUMO

AIMS: Sodium-glucose cotransporter-2 inhibitors (SGLT-2i) have off-target effects on haemoconcentration and anti-inflammation. The impact of SGLT-2i on the risk of venous thromboembolism (VTE) in patients with diabetes mellitus (DM) remains unclear. This study aimed to evaluate the risk of newly diagnosed VTE in patients with DM using SGLT-2i in comparison to dipeptidyl peptidase-4 inhibitors (DPP-4i) or glucagon-like peptide-1 receptor agonists (GLP-1RA). MATERIALS AND METHODS: In this nationwide retrospective cohort study, we used data from Taiwan's National Health Insurance Research Database. Patients with diabetes aged 20 years or older who received SGLT-2i, DPP-4i, or GLP-1RA between 1 May 2016, and 31 December 2020, were included. The risks of VTE in SGLT-2i users were compared with those of DPP-4i and GLP-1RA users. A Cox regression model with stabilised inverse probability of treatment weighting was used to calculate hazard ratio (HR) for VTE risk. Additionally, a meta-analysis of relevant articles published before 23 May 2023, was conducted. RESULTS: Data from 136,530 SGLT-2i, 598,280 DPP-4i, and 5760 GLP-1RA users were analysed. SGLT-2i use was associated with a lower risk of VTE than DPP-4i (HR, 0.70; 95% CI, 0.59-0.84; p < 0·001), but not with GLP-1RA (HR, 1.39; 95% CI, 0.32-5.94; p = 0.66). Our meta-analysis further supported these findings (SGLT-2i vs. DPP-4i: HR, 0.71; 95% CI, 0.62-0.82; p < 0·001; SGLT-2i vs. GLP-1RA: HR, 0.91; 95% CI, 0.73-1.15; p = 0.43), suggesting the robustness of our retrospective analysis. CONCLUSIONS: In patients with DM, SGLT-2i was associated with a lower risk of VTE compared to DPP-4i, but not GLP-1RA.


Assuntos
Diabetes Mellitus Tipo 2 , Inibidores da Dipeptidil Peptidase IV , Inibidores do Transportador 2 de Sódio-Glicose , Simportadores , Tromboembolia Venosa , Humanos , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Hipoglicemiantes/efeitos adversos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/induzido quimicamente , Tromboembolia Venosa/induzido quimicamente , Tromboembolia Venosa/epidemiologia , Estudos Retrospectivos , Inibidores da Dipeptidil Peptidase IV/efeitos adversos , Glucose , Sódio , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas
12.
Cerebellum ; 23(1): 92-100, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36598718

RESUMO

Extensive evidence supports the claim that the serum neurofilament light chain (sNfL) can be used as a biomarker to monitor disease severity in patients with spinocerebellar ataxia type 3 (SCA3). However, little is known about the associations between sNfL levels and neurochemical alterations in SCA3 patients. In this study, we performed a cross-sectional study to analyze the association between sNfL and brain metabolic changes in SCA3 patients. The severity of ataxia was assessed by using the Scale for the Assessment and Rating of Ataxia (SARA) and the International Cooperative Ataxia Rating Scale (ICARS). The sNfL levels and brain metabolic changes, represented by N-acetyl aspartate (NAA)/creatine (Cr) and choline complex (Cho)/Cr ratios, were measured by a single-molecule array and proton magnetic resonance spectroscopy, respectively. In this cohort, we observed consistently elevated sNfL levels and reduced brain metabolites in the cerebellar hemispheres, dentate nucleus, and cerebellar vermis. However, this correlation was further validated in the cerebellar cortex after analysis using pairwise comparisons and a Bonferroni correction. Taken together, our results further confirmed that sNfL levels were increased in SCA3 patients and were negatively correlated with metabolic changes in the cerebellar cortex. Our data also support the idea that sNfL levels are a promising potential complementary biomarker for patients with SCA3.


Assuntos
Ataxia Cerebelar , Doença de Machado-Joseph , Neuroquímica , Humanos , Estudos Transversais , Filamentos Intermediários/metabolismo , Filamentos Intermediários/patologia , Proteínas de Neurofilamentos , Ataxia , Biomarcadores
13.
Crit Rev Food Sci Nutr ; : 1-11, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38356229

RESUMO

Immunoassay based on the antibodies specific for targets has advantages of high sensitivity, simplicity and low cost, therefore it has received more attention in recent years, especially for the rapid detection of small molecule chemicals present in foods, diagnostics and environments. However, limited by low molecular weight and only one antigenic determinant existed, immunoassays for these small molecule chemicals, namely hapten substances, were commonly performed in a competitive immunoassay format, whose sensitivities were obviously lower than the sandwich enzyme-linked immunosorbent assay generally adaptable for the protein targets. In order to break through the bottleneck of detection format, researchers have designed and established several novel noncompetitive immunoassays for the haptens in the past few years. In this review, we focused on the four representative types of noncompetitive immunoassay formats and described their characteristics and applications in rapid detection of small molecules. Meanwhile, a systematic discussion on the current technologies challenges and the possible solutions were also summarized. This review aims to provide an updated overview of the current state-of-the-art in noncompetitive immunoassay for small molecules, and inspire the development of novel designs for small molecule detection.

14.
J Org Chem ; 89(12): 8435-8446, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38843406

RESUMO

Both the 3-fluorooxindole and germinal bisphosphonate structural motifs are prevalent in bioactive molecules because of their associated biological activities. We describe an approach to accessing 3,3-disubstituted 3-fluorooxindoles bearing a geminal bisphosphate fragment through a highly enantioselective Michael addition reaction between 3-fluorooxindoles and vinylidene bisphosphonates. These reactions are catalyzed by a commercially available cinchona alkaloid catalyst, have a broad substrate scope concerning 3-fluorooxindoles, and provide the corresponding addition products in a yield of up to 95% with an enantiomeric excess of up to 95%. A reasonable reaction pathway to explain the observed stereochemistry is also proposed.

15.
Bioorg Med Chem Lett ; 98: 129585, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38086468

RESUMO

Ceramides, crucial sphingolipids in cellular biology, play various roles ranging from structural membrane integrity to signaling pathway regulation. Structurally, a ceramide consists of a fatty acid connected to a sphingoid base. The characteristics of the fatty acid chain, including length and saturation, determine the physiological properties of the ceramide. Ceramides typically fall into the following categories based on chain length: medium, long, very-long, and ultra-long. Among them, two very-long-chain ceramides, Cer(24:1(15Z)) and Cer(24:0), have been extensively studied, and they are known for their regulatory functions. However, the hydrophobic natures of ceramides, arising from their long hydrocarbon chain impedes their solubilities and levels of cellular delivery. Although ω-pyridinium ceramide analogs (ω-PyrCers) have been developed to address this issue, ω-PyrCers with very-long fatty acid chains or unsaturation have not been developed, presumably due to limited access to the corresponding ω-bromo fatty acids required in their syntheses. In this study, we prepared the ω-PyrCers of Cer(24:1(15Z)) and Cer(24:0), PyrCer(24:1(15Z)) and PyrCer(24:0), respectively. The key in the synthesis is the Wittig reaction to prepare the ω-bromo fatty acid with an appropriate chain length and (Z)-double bond position. Preliminary evaluation of the PyrCer(24:1(15Z)) and PyrCer(24:0) revealed their potential in hepatocellular carcinoma treatment.


Assuntos
Antineoplásicos , Ceramidas , Esfingolipídeos , Ceramidas/farmacologia , Ceramidas/química , Ácidos Graxos/farmacologia , Compostos de Piridínio/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico
16.
Environ Sci Technol ; 58(18): 7838-7848, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38656157

RESUMO

Large volumes of water are used in energy production for both primary (e.g., fuel extraction) and secondary energy (e.g., electricity). In countries such as China, with a large internal trade in fuels and long-distance transmission grids, this can result in considerable water inequalities. Previous research focused on the water impacts of energy production at the national and provincial levels, which is too coarse to identify the spatial differences and make specific case studies. Here, we take the next step toward a spatially explicit economically integrated water-use for energy assessment by combining a bottom-up assessment approach with a city-level multiregional input-output model. Specifically, we examine the water consumption of energy production in China, distinguishing between water for primary and secondary energy at the level of coal mines, oil and gas fields, and power plants for the first time. Of the total energy-related freshwater consumption of 4.9 Gm3 in 2017, primary energy accounted for 19% (940 Mm3) and secondary energy accounted for 81% (3955 Mm3). Coal was the largest water consumer for both primary and secondary energy (540 and 3880 Mm3, respectively), with both oil (361, and 0.5 Mm3, respectively) and gas (7 and 69 Mm3, respectively) also consuming large amounts. Intercity virtual water, that is, water embodied in energy trade across cities, reached 54% (2.6 Gm3) of energy-related freshwater consumption. Across China, 32% of cities see a bilateral trade in secondary- and primary-energy-related virtual water (e.g., Daqing city exports virtual water embodied in primary fuel to other cities that is then used to produce electricity in those cities, part of which is used back in Daqing via transmission). For these 32% of cities, 73% export more virtual water than import and 27% import more virtual water than export. This study reveals significant differences in city-level virtual water patterns (e.g., scale and direction) between primary and secondary energy to provide information for cities about their virtual water inflow and outflow and the potential collaboration partners for water management.


Assuntos
Cidades , China , Centrais Elétricas , Água
17.
J Immunol ; 209(7): 1359-1369, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36165200

RESUMO

Donor-specific HLA Abs contribute to Ab-mediated rejection (AMR) by binding to HLA molecules on endothelial cells (ECs) and triggering intracellular signaling, leading to EC activation and leukocyte recruitment. The molecular mechanisms involving donor-specific HLA Ab-mediated EC activation and leukocyte recruitment remain incompletely understood. In this study, we determined whether TLRs act as coreceptors for HLA class I (HLA I) in ECs. We found that human aortic ECs express TLR3, TLR4, TLR6, and TLR10, but only TLR4 was detected on the EC surface. Consequently, we performed coimmunoprecipitation experiments to examine complex formation between HLA I and TLR4. Stimulation of human ECs with HLA Ab increased the amount of complex formation between HLA I and TLR4. Reciprocal coimmunoprecipitation with a TLR4 Ab confirmed that the crosslinking of HLA I increased complex formation between TLR4 and HLA I. Knockdown of TLR4 or MyD88 with small interfering RNAs inhibited HLA I Ab-stimulated P-selectin expression, von Willebrand factor release, and monocyte recruitment on ECs. Our results show that TLR4 is a novel coreceptor for HLA I to stimulate monocyte recruitment on activated ECs. Taken together with our previous published results, we propose that HLA I molecules form two separate signaling complexes at the EC surface, that is, with TLR4 to upregulate P-selectin surface expression and capture of monocytes to human ECs and integrin ß4 to induce mTOR-dependent firm monocyte adhesion via ICAM-1 clustering on ECs, two processes implicated in Ab-mediated rejection.


Assuntos
Células Endoteliais , Molécula 1 de Adesão Intercelular , Células Cultivadas , Endotélio Vascular/metabolismo , Antígenos HLA/metabolismo , Humanos , Integrina beta4/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Monócitos , Fator 88 de Diferenciação Mieloide/metabolismo , Selectina-P/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Receptor 3 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Receptor 6 Toll-Like/metabolismo , Fator de von Willebrand/metabolismo
18.
Acta Pharmacol Sin ; 45(3): 449-464, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37993536

RESUMO

As the hub of cellular lipid metabolism, lipid droplets (LDs) have been linked to a variety of biological processes. During pathogen infection, the biogenesis, composition, and functions of LDs are tightly regulated. The accumulation of LDs has been described as a hallmark of pathogen infection and is thought to be driven by pathogens for their own benefit. Recent studies have revealed that LDs and their subsequent lipid mediators contribute to effective immunological responses to pathogen infection by promoting host stress tolerance and reducing toxicity. In this comprehensive review, we delve into the intricate roles of LDs in governing the replication and assembly of a wide spectrum of pathogens within host cells. We also discuss the regulatory function of LDs in host immunity and highlight the potential for targeting LDs for the diagnosis and treatment of infectious diseases.


Assuntos
Gotículas Lipídicas , Lipídeos , Metabolismo dos Lipídeos
19.
Environ Res ; 251(Pt 2): 118303, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38295978

RESUMO

A novel intercalated nanocomposite of mercapto-modified cellulose/bentonite (LCS-BE-SH) was synthesized by high-speed shearing method in one step at room temperature, and was applied to remove Cd from solution and remediate Cd-contaminated soil. Results revealed that cellulose long-chain molecules have intercalated into bentonite nanolayers and interlayer spacing was increased to 1.411 nm, and grafting -SH groups improved adsorption selectivity, which enabled LCS-BE-SH to have distinct capability of Cd adsorption (qmax = 147.21 mg/g). Kinetic and thermodynamics showed that Cd adsorption onto LCS-BE-SH was well fitted by pseudo-second-order and Langmuir adsorption isotherm. Characterizations of the adsorbents revealed that synergistic effect of complexation (e.g., CdS, CdO) and precipitation (e.g., Cd(OH)2, CdCO3) mechanism played a major role in Cd removal. In soil remediation, application of LCS-BE-SH was most effective (67.31 %) in Cd immobilization compared to the control (8.85 %), which reduced exchangeable Cd from 37.03 % to 11.44 %. Meanwhile, soil pH, soil organic matter, available phosphorus, and enzyme activities (catalase, urease, and dehydrogenase) were improved LCS-BE-SH treatment. The main immobilization mechanism in soil included complexation (e.g., CdS, CdO) and precipitation (e.g., Cd(OH)2, Cd-Fe-hydroxide). Overall, this work applied a promising approach for Cd removal in aqueous and Cd remediation in soil by using an effective eco-friendly LCS-BE-SH nanocomposites.


Assuntos
Bentonita , Cádmio , Celulose , Recuperação e Remediação Ambiental , Nanocompostos , Poluentes do Solo , Bentonita/química , Cádmio/química , Nanocompostos/química , Poluentes do Solo/química , Recuperação e Remediação Ambiental/métodos , Celulose/química , Adsorção
20.
Mol Cell ; 64(3): 443-454, 2016 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-27773675

RESUMO

Mediator is a transcriptional co-activator recruited to enhancers by DNA-binding activators, and it also interacts with RNA polymerase (Pol) II as part of the preinitiation complex (PIC). We demonstrate that a single Mediator complex associates with the enhancer and core promoter in vivo, indicating that it can physically bridge these transcriptional elements. However, the Mediator kinase module associates strongly with the enhancer, but not with the core promoter, and it dissociates from the enhancer upon depletion of the TFIIH kinase. Severing the kinase module from Mediator by removing the connecting subunit Med13 does not affect Mediator association at the core promoter but increases occupancy at enhancers. Thus, Mediator undergoes a compositional change in which the kinase module, recruited via Mediator to the enhancer, dissociates from Mediator to permit association with Pol II and the PIC. As such, Mediator acts as a dynamic bridge between the enhancer and core promoter.


Assuntos
Regulação Fúngica da Expressão Gênica , Complexo Mediador/genética , RNA Polimerase II/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Sítios de Ligação , Elementos Facilitadores Genéticos , Complexo Mediador/metabolismo , Regiões Promotoras Genéticas , Ligação Proteica , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , RNA Polimerase II/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Fator de Transcrição TFIIH/genética , Fator de Transcrição TFIIH/metabolismo , Iniciação da Transcrição Genética , Ativação Transcricional
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