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1.
Nature ; 586(7827): E7, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32934359

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

2.
Nature ; 577(7791): E6, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31896818

RESUMO

An Amendment to this paper has been published and can be accessed via a link at the top of the paper.

3.
Nature ; 572(7770): 528-532, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31391582

RESUMO

During post-implantation development of the mouse embryo, descendants of the inner cell mass in the early epiblast transit from the naive to primed pluripotent state1. Concurrently, germ layers are formed and cell lineages are specified, leading to the establishment of the blueprint for embryogenesis. Fate-mapping and lineage-analysis studies have revealed that cells in different regions of the germ layers acquire location-specific cell fates during gastrulation2-5. The regionalization of cell fates preceding the formation of the basic body plan-the mechanisms of which are instrumental for understanding embryonic programming and stem-cell-based translational study-is conserved in vertebrate embryos6-8. However, a genome-wide molecular annotation of lineage segregation and tissue architecture of the post-implantation embryo has yet to be undertaken. Here we report a spatially resolved transcriptome of cell populations at defined positions in the germ layers during development from pre- to late-gastrulation stages. This spatiotemporal transcriptome provides high-resolution digitized in situ gene-expression profiles, reveals the molecular genealogy of tissue lineages and defines the continuum of pluripotency states in time and space. The transcriptome further identifies the networks of molecular determinants that drive lineage specification and tissue patterning, supports a role of Hippo-Yap signalling in germ-layer development and reveals the contribution of visceral endoderm to the endoderm in the early mouse embryo.


Assuntos
Linhagem da Célula , Embrião de Mamíferos/citologia , Embrião de Mamíferos/embriologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteínas de Ciclo Celular/metabolismo , Diferenciação Celular , Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário , Regulação da Expressão Gênica no Desenvolvimento , Camadas Germinativas/citologia , Camadas Germinativas/embriologia , Camadas Germinativas/metabolismo , Via de Sinalização Hippo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Serina-Treonina Quinases/metabolismo , Regulon/genética , Transdução de Sinais , Transcriptoma/genética , Proteínas de Sinalização YAP
4.
Arch Biochem Biophys ; 754: 109962, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38499055

RESUMO

Acetohydroxyacid synthase (AHAS) is one of the key enzymes of the biosynthesis of branched-chain amino acids, it is also an effective target for the screening of herbicides and antibiotics. In this study we present a method for preparing Escherichia coli AHAS I holoenzyme (EcAHAS I) with exceptional stability, which provides a solid ground for us to re-investigate the in vitro catalytic properties of the protein. The results show EcAHAS I synthesized in this way exhibits similar function to Bacillus subtilis acetolactate synthase in its catalysis with pyruvate and 2-ketobutyrate (2-KB) as dual-substrate, producing four 2-hydroxy-3-ketoacids including (S)-2-acetolactate, (S)-2-aceto-2-hydroxybutyrate, (S)-2-propionyllactate, and (S)-2-propionyl-2-hydroxybutyrate. Quantification of the reaction indicates that the two substrates almost totally consume, and compound (S)-2-aceto-2- hydroxybutyrate forms in the highest yield among the four major products. Moreover, the protein also condenses two molecules of 2-KB to furnish (S)-2-propionyl-2-hydroxybutyrate. Further exploration manifests that EcAHAS I ligates pyruvate/2-KB and nitrosobenzene to generate two arylhydroxamic acids N-hydroxy-N-phenylacetamide and N-hydroxy-N-phenyl- propionamide. These findings enhance our comprehension of the catalytic characteristics of EcAHAS I. Furthermore, the application of this enzyme as a catalyst in construction of C-N bonds displays promising potential.


Assuntos
Acetolactato Sintase , Escherichia coli , Acetolactato Sintase/química , Glicogênio Sintase , Hidroxibutiratos , Piruvatos , Holoenzimas
5.
Neuroimage ; 271: 120041, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36933626

RESUMO

Brain lesion segmentation provides a valuable tool for clinical diagnosis and research, and convolutional neural networks (CNNs) have achieved unprecedented success in the segmentation task. Data augmentation is a widely used strategy to improve the training of CNNs. In particular, data augmentation approaches that mix pairs of annotated training images have been developed. These methods are easy to implement and have achieved promising results in various image processing tasks. However, existing data augmentation approaches based on image mixing are not designed for brain lesions and may not perform well for brain lesion segmentation. Thus, the design of this type of simple data augmentation method for brain lesion segmentation is still an open problem. In this work, we propose a simple yet effective data augmentation approach, dubbed as CarveMix, for CNN-based brain lesion segmentation. Like other mixing-based methods, CarveMix stochastically combines two existing annotated images (annotated for brain lesions only) to obtain new labeled samples. To make our method more suitable for brain lesion segmentation, CarveMix is lesion-aware, where the image combination is performed with a focus on the lesions and preserves the lesion information. Specifically, from one annotated image we carve a region of interest (ROI) according to the lesion location and geometry with a variable ROI size. The carved ROI then replaces the corresponding voxels in a second annotated image to synthesize new labeled images for network training, and additional harmonization steps are applied for heterogeneous data where the two annotated images can originate from different sources. Besides, we further propose to model the mass effect that is unique to whole brain tumor segmentation during image mixing. To evaluate the proposed method, experiments were performed on multiple publicly available or private datasets, and the results show that our method improves the accuracy of brain lesion segmentation. The code of the proposed method is available at https://github.com/ZhangxinruBIT/CarveMix.git.


Assuntos
Neoplasias Encefálicas , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Encéfalo
6.
J Am Chem Soc ; 145(26): 14251-14259, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37352463

RESUMO

Prenylated indole alkaloids (PIAs) possess great structural diversity and show biological activities. Despite significant efforts in investigating the biosynthetic mechanism, the key step in the transformation of 2,5-diazabicyclo[2.2.2]octane-containing PIAs into a distinct class of pentacyclic compounds remains unknown. Here, using a combination of gene deletion, heterologous expression, and biochemical characterization, we show that a unique fungal P450 enzyme CtdY catalyzes the cleavage of the amide bond in the 2,5-diazabicyclo[2.2.2]octane system, followed by a decarboxylation step to form the 6/5/5/6/6 pentacyclic ring in 21R-citrinadin A. We also demonstrate the function of a subsequent cascade of stereospecific oxygenases to further modify the 6/5/5/6/6 pentacyclic intermediate en route to the complete 21R-citrinadin A biosynthesis. Our findings reveal a key enzyme CtdY for the pathway divergence in the biosynthesis of PIAs and uncover the complex late-stage post-translational modifications in 21R-citrinadin A biosynthesis.


Assuntos
Sistema Enzimático do Citocromo P-450 , Octanos , Sistema Enzimático do Citocromo P-450/metabolismo , Alcaloides Indólicos
7.
J Am Chem Soc ; 145(34): 19098-19106, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37603884

RESUMO

Mechanosensitive ion channels play crucial roles in physiological activities, where small mechanical stimuli induce the membrane tension, trigger the ion channels' deformation, and are further transformed into significant electrochemical signals. Artificial ion channels with stiff moduli have been developed to mimic mechanosensory behaviors, exhibiting an electrochemical response by the high-pressure-induced flow. However, fabricating flexible mechanosensitive channels capable of regulating specific ion transporting upon dramatic deformation has remained a challenge. Here, we demonstrate bioinspired high-density elastomeric channels self-assembled by polyisoprene-b-poly4-vinylpyridine, which exhibit ultra-mechanosensitive chloride ion transport resulting from nanochannel deformation. The PI-formed continuous elastic matrix can transmit external forces into internal tensions, while P4VP forms transmembrane chloride channels that undergo dramatic deformation and respond to mechanical stimuli. The integrated and flexible chloride channels present a dramatic and stable electrochemical signal toward a low pressure of 0.2 mbar. This research first demonstrates the artificial mechanosensory chloride channels, which could provide a promising avenue for designing flexible and responsive channel systems.

8.
J Am Chem Soc ; 145(1): 413-421, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36542862

RESUMO

Genome mining of cryptic natural products (NPs) remains challenging, especially in filamentous fungi, owing to their complex genetic regulation. Increasing evidence indicates that several epigenetic modifications often act cooperatively to control fungal gene transcription, yet the ability to predictably manipulate multiple genes simultaneously is still largely limited. Here, we developed a multiplex base-editing (MBE) platform that significantly improves the capability and throughput of fungal genome manipulation, leading to the simultaneous inactivation of up to eight genes using a single transformation. We then employed MBE to inactivate three negative epigenetic regulators combinatorially in Aspergillus nidulans, enabling the activation of eight cryptic gene clusters compared to the wild-type strains. A group of novel NPs harboring unique cichorine and polyamine hybrid chemical scaffolds were identified, which were not reported previously. We envision that our scalable and efficient MBE platform can be readily applied in other filamentous fungi for the genome mining of novel NPs, providing a powerful approach for the exploitation of fungal chemical diversity.


Assuntos
Aspergillus nidulans , Produtos Biológicos , Epigênese Genética , Genes Fúngicos , Genoma Fúngico , Fungos/genética , Aspergillus nidulans/genética , Família Multigênica
9.
Small ; 19(6): e2205800, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36587989

RESUMO

The ability to control the density and spatial distribution of substitutional dopants in semiconductors is crucial for achieving desired physicochemical properties. Substitutional doping with adjustable doping levels has been previously demonstrated in 2D transition metal dichalcogenides (TMDs); however, the spatial control of dopant distribution remains an open field. In this work, edge termination is demonstrated as an important characteristic of 2D TMD monocrystals that affects the distribution of substitutional dopants. Particularly, in chemical vapor deposition (CVD)-grown monolayer WS2 , it is found that a higher density of transition metal dopants is always incorporated in sulfur-terminated domains when compared to tungsten-terminated domains. Two representative examples demonstrate this spatial distribution control, including hexagonal iron- and vanadium-doped WS2 monolayers. Density functional theory (DFT) calculations are further performed, indicating that the edge-dependent dopant distribution is due to a strong binding of tungsten atoms at tungsten-zigzag edges, resulting in the formation of open sites at sulfur-zigzag edges that enable preferential dopant incorporation. Based on these results, it is envisioned that edge termination in crystalline TMD monolayers can be utilized as a novel and effective knob for engineering the spatial distribution of substitutional dopants, leading to in-plane hetero-/multi-junctions that display fascinating electronic, optoelectronic, and magnetic properties.

10.
BMC Endocr Disord ; 23(1): 114, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37217896

RESUMO

BACKGROUND: Hyperhomocysteinemia has been linked with chronic kidney disease (CKD). The present study investigated whether homocysteine (Hcy) serum levels might serve as a marker for the advancement of diabetic nephropathy (DN). METHODS: Clinical and laboratory indicators including Hcy, vitamin D (VD), urine protein, estimated glomerular filtration rate (eGFR) and the urinary protein/creatinine ratio in subjects > 65 years with DN (n = 1,845), prediabetes (n = 1,180) and in a non-diabetes (control) group (n = 28,720) were analyzed. RESULTS: DN patients had elevated Hcy concentrations, decreased VD and higher urinary protein levels, a reduced eGFR and a higher urinary protein/creatinine ratio compared with prediabetic and control subjects. After correcting for urinary protein quantitation, multivariate analysis revealed that both the Hcy concentration (P < 0.010) and urinary protein/creatinine ratio (P < 0.001) were risk factors, while the VD2 + VD3 serum concentration (P < 0.001) was a protective factor for DN. Moreover, Hcy > 12 µmol/L was a cut-off value for predicting advanced DN. CONCLUSION: Hcy serum concentration is a potential marker for the advancement of CKD in DN but not prediabetes patients.


Assuntos
Nefropatias Diabéticas , Estado Pré-Diabético , Insuficiência Renal Crônica , Humanos , Idoso , Nefropatias Diabéticas/diagnóstico , Nefropatias Diabéticas/etiologia , Creatinina , Testes de Função Renal , Insuficiência Renal Crônica/diagnóstico , Taxa de Filtração Glomerular , Estado Pré-Diabético/diagnóstico
11.
Biol Res ; 56(1): 5, 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36732854

RESUMO

BACKGROUND: Alpha-kinase 1 (ALPK1) is a master regulator in inflammation and has been proved to promote renal fibrosis by promoting the production of IL-1ß in diabetic nephropathy (DN) mice. Pyroptosis is involved in high glucose (HG)-induced tubular cells injury, characterized by activation of Gasdermin D (GSDMD) and the release of IL-1ß and IL-18, resulting in inflammatory injury in DN. It is reasonable to assume that ALPK1 is involved in pyroptosis-related tubular injury in DN. However, the mechanism remains poorly defined. METHODS: Immunohistochemistry (IHC) staining was performed to detect the expression of pyroptosis- and fibrosis-related proteins in renal sections of DN patients and DN mice. DN models were induced through injection of streptozotocin combined with a high-fat diet. Protein levels of ALPK1, NF-κB, Caspase-1, GSDMD, IL-1ß, IL-18 and α-SMA were detected by Western blot. HK-2 cells treated with high-glucose (HG) served as an in vitro model. ALPK1 small interfering RNA (siRNA) was transfected into HK-2 cells to down-regulate ALPK1. The pyroptosis rates were determined by flow cytometry. The concentrations of IL-1ß and IL-18 were evaluated by ELISA kits. Immunofluorescence staining was used to observe translocation of NF-κB and GSDMD. RESULTS: The heat map of differentially expressed genes showed that ALPK1, Caspase-1 and GSDMD were upregulated in the DN group. The expression levels of ALPK1, Caspase-1, GSDMD and CD68 were increased in renal biopsy tissues of DN patients by IHC. ALPK1expression and CD68+ macrophages were positively correlated with tubular injury in DN patients. Western blot analysis showed increased expressions of ALPK1, phospho-NF-κB P65, GSDMD-NT, and IL-1ß in renal tissues of DN mice and HK-2 cells, accompanied with increased renal fibrosis-related proteins (FN, α-SMA) and macrophages infiltration in interstitial areas. Inhibition of ALPK1 attenuated HG-induced upregulation expressions of NF-κB, pyroptosis-related proteins Caspase-1, GSDMD-NT, IL-1ß, IL-18, α-SMA, and pyroptosis level in HK-2 cells. Also, the intensity and nuclear translocation of NF-κB and membranous translocation of GSDMD were ameliorated in HG-treated HK-2 cells after treatment with ALPK1 siRNA. CONCLUSIONS: Our data suggest that ALPK1/NF-κB pathway initiated canonical caspase-1-GSDMD pyroptosis pathway, resulting in tubular injury and interstitial inflammation of DN.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Animais , Camundongos , Caspases , Fibrose , Glucose , Inflamação , Interleucina-18 , NF-kappa B/metabolismo , Piroptose , RNA Interferente Pequeno
12.
Drug Dev Res ; 84(2): 143-155, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36464837

RESUMO

Cholestasis is a main clinical feature of biliary atresia (BA), which leads to liver fibrosis (LF). The focus of BA treatment is preventing and slowing the progress of LF. This study reports the improvement effect of anlotinib on common bile duct ligature (BDL)-induced LF in young rats. The BDL young rats were treated with anlotinib and the serum levels of aspartate aminotransferase, alanine aminotransferase, albumin, and total bilirubin were determined. Histological staining was performed and pathological changes in liver tissue were observed. The expression levels of α-SMA, collagen I, CD31, TGF-ß1, phospho-VEGFR2, phospho-4E/BP1, and phospho-S6K1 were determined. The results showed that anlotinib significantly improved the liver function and histopathological injury of BDL rats, inhibited the deposition of collagen and hepatocyte apoptosis, and downregulated the protein expression of α-SMA and collagen I. Furthermore, anlotinib treatment significantly inhibited microvascular formation in the liver and downregulated the expression level of phospho-VEGFR2, thereby suggesting that the antifibrosis effect of anlotinib may be achieved by antiangiogenesis. In addition, anlotinib downregulated the expression of phospho-S6K1 and upregulated the expression of phospho-4E/BP1, two downstream proteins of the mammalian target of rapamycin (mTOR) pathway. MHY1485, an agonist of mTOR, significantly reversed the inhibitory effect of anlotinib on angiogenesis and LF but did not influence the effect of anlotinib on the downregulation of phospho-VEGFR2 expression. Together, the above-mentioned results suggest that the effect of anlotinib on BDL-induced LF involves at least antiangiogenesis regulated by the VEGFR2/mTOR signaling pathway.


Assuntos
Ductos Biliares , Fígado , Ratos , Animais , Ductos Biliares/cirurgia , Ductos Biliares/metabolismo , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/patologia , Colágeno/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Mamíferos/metabolismo
13.
Clin Sci (Lond) ; 136(24): 1877-1891, 2022 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-36449316

RESUMO

Sepsis is a leading cause of acute kidney injury (AKI), and the pathogenesis of septic AKI remains largely unclear. Parkinson disease protein 7 (PARK7) is a protein of multiple functions that was recently implicated in septic AKI, but the underlying mechanism is unknown. In the present study, we determined the role of PARK7 in septic AKI and further explored the underlying mechanism in lipopolysaccharide (LPS)-induced endotoxic models. PARK7 was induced both in vivo and in vitro following LPS treatment. Compared with wild-type (WT) mice, Park7-deficient mice experienced aggravated kidney tissue damage and dysfunction, and enhanced tubular apoptosis and inflammation following LPS treatment. Consistently, LPS-induced apoptosis and inflammation in renal tubular cells in vitro were exacerbated by Park7 knockdown, whereas they were alleviated by PARK7 overexpression. Mechanistically, silencing Park7 facilitated nuclear translocation and phosphorylation of p65 (a key component of the nuclear factor kappa B [NF-κB] complex) during LPS treatment, whereas PARK7 overexpression partially prevented these changes. Moreover, we detected PARK7 interaction with p65 in the cytoplasm in renal tubular cells, which was enhanced by LPS treatment. Collectively, these findings suggest that PARK7 is induced to protect against septic AKI through suppressing NF-κB signaling.


Assuntos
Injúria Renal Aguda , Doença de Parkinson , Sepse , Camundongos , Animais , NF-kappa B/metabolismo , Endotoxinas/efeitos adversos , Lipopolissacarídeos/farmacologia , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/genética , Injúria Renal Aguda/prevenção & controle , Inflamação/patologia , Sepse/metabolismo , Proteína Desglicase DJ-1
14.
Nano Lett ; 21(16): 6882-6890, 2021 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-34387492

RESUMO

Through its ability to image liquid-phase dynamics at nano/atomic-scale resolution, liquid-cell electron microscopy is essential for a wide range of applications, including wet-chemical synthesis, catalysis, and nanoparticle tracking, for which involved structural features are critical. However, statistical investigations by usual techniques remain challenging because of the difficulty in fabricating substantial liquid cells with appreciable efficiency. Here, we report a general approach for efficiently printing huge numbers of ready-to-use liquid cells (∼9000) within 30 s by electrospinning, with the unique feature of statistical liquid-phase studies requiring only one experimental time slot. Our solution efficiently resolves a complete transition picture of bubble evolution and also the induced nanoparticle motion. We statistically quantify the effect of the electron dose rate on the bubble variation and conclude that the bubble-driven nanoparticle motion is a ballistic-like behavior insignificant to morphological asymmetries. The versatile approach here is critical for statistical research, offering great opportunities in liquid-phase-associated dynamic studies.


Assuntos
Nanopartículas , Catálise , Microscopia Eletrônica , Movimento (Física) , Impressão Tridimensional
15.
Planta ; 254(6): 133, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34821984

RESUMO

MAIN CONCLUSION: A pollen specific homolog to a xyloglucan galactosyltransferase regulates cell wall stability and therefore pollen tube growth in Arabidopsis. In angiosperms, pollen tubes grow through the transmitting tract to deliver the sperm cells to the ovule for fertilization. Fast growing pollen tubes coordinate the synthesis, secretion and assembly of cell wall components to maintain the mechanical properties of the cell wall. Xyloglucan, the major hemicellulosic polysaccharide in the primary cell wall, tethers cellulose to form the complexed cell wall network through its side chain modifications. How the side chain modifications of the xyloglucan regulate the pollen tube cell wall strength and growth remains elusive. Here we found that AtGT11, a MUR3 xyloglucan galactosyltransferase homolog highly expressed in pollen regulated the cell wall stability of pollen tubes. Genetic analysis of the gt11 and the xylosyltransferase 1/2 mutant indicated that the xylosylation of XyG side chains played dominant role while galactosylation of the XyG side chains finely modified the cell wall mechanics.


Assuntos
Tubo Polínico , Xilanos , Parede Celular , Glucanos
16.
Toxicol Appl Pharmacol ; 418: 115492, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33722665

RESUMO

Cisplatin is a commonly used anti-cancer drug, but it induces nephrotoxicity. As a water-soluble vitamin B family member, nicotinamide (NAM) was recently demonstrated to have beneficial effects for renal injury, but its underlying mechanism remains largely unclear. Here, we suggest that NAM may exert protective effects against cisplatin-induced acute kidney injury (AKI) mainly via suppressing the poly ADP-ribose polymerase 1 (PARP1)/p53 pathway. In our experiment, NAM protected against cisplatin-induced apoptosis both in cultured renal proximal tubular cells and AKI in mice. Mechanistically, NAM suppressed the expression and activation of p53, a known mediator of cisplatin-induced AKI. Upstream of p53, NAM attenuated the induction of γ-H2AX, a hallmark of DNA damage response. Interestingly, PARP1 was activated in cisplatin AKI and this activation was inhibited by NAM. Pharmacological inhibition of PARP1 with PJ34 significantly ameliorated p53 activation and cisplatin-induced cell death in RPTCs and AKI in mice. Thus, NAM may protect against cisplatin-induced AKI by suppressing the PARP1/p53 pathway.


Assuntos
Injúria Renal Aguda/prevenção & controle , Cisplatino , Túbulos Renais Proximais/efeitos dos fármacos , Niacinamida/farmacologia , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/enzimologia , Injúria Renal Aguda/patologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Modelos Animais de Doenças , Histonas/metabolismo , Túbulos Renais Proximais/enzimologia , Túbulos Renais Proximais/patologia , Masculino , Camundongos Endogâmicos C57BL , Fosfoproteínas/metabolismo , Poli(ADP-Ribose) Polimerase-1/metabolismo , Ratos , Transdução de Sinais
17.
Exp Physiol ; 106(7): 1631-1642, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33914383

RESUMO

NEW FINDINGS: What is the central question of this study? Diabetic nephropathy (DN) is a severe complication of diabetes correlated with a higher mortality rate in diabetic patients. Renal tubular injury participates in the pathogenesis of DN. We aimed to uncover the biological function of the NEAT1-miR-150-5p-DRP1 axis in an in vitro model of DN and elaborate the potential mechanisms. What is the main finding and its importance? NEAT1 facilitated high glucose-induced damage in HK-2 cells by reducing mitophagy via the miR-150-5p-DRP1 axis, which sheds light on DN pathogenesis and reveals a potential treatment for DN. ABSTRACT: Diabetic nephropathy (DN) is a severe complication in diabetic patients, with a high mortality rate. Renal tubular injury is involved in the pathogenesis of DN. In this study, we aimed to uncover the regulatory roles of the NEAT1-miR-150-5p-DRP1 axis in an in vitro model of DN and its possible mechanisms. High glucose-challenged HK-2 cells were used as an in vitro DN model. NEAT1, miR-150-5p and DRP1 levels were assessed by RT-qPCR. Cell viability was determined by the MTT assay. MitoSOX Red and JC-1 were used to evaluate intracellular production of reactive oxygen species and mitochondrial membrane potential, respectively. Lactate dehydrogenase release and superoxide dismutase activity were assessed with commercial kits. The protein levels of DRP1, p62, BECN1(beclin 1) and BNIP3 were determined by western blotting. The interaction between NEAT1 (DRP1) and miR-150-5p was verified by a dual-luciferase reporter assay and an RNA immunoprecipitation assay. Our results showed that in response to high glucose the NEAT1 and DRP1 levels were upregulated, whereas the miR-150-5p level was downregulated in HK-2 cells. Knockdown of NEAT1 or DRP1 in high glucose-challenged HK-2 cells inhibited excessive reactive oxygen species production and lactate dehydrogenase release, increased cell viability, mitochondrial membrane potential and superoxide dismutase activity and enhanced mitophagy. Inhibition of miR-150-5p resulted in the opposite results. Mechanistically, NEAT1 sponged miR-150-5p to increase the DRP1 level. Moreover, silencing of NEAT1 or DRP1 could counteract miR-150-5p inhibition-induced deleterious effects. Collectively, our findings indicate that NEAT1 facilitates high glucose-induced damage in HK-2 cells by suppressing mitophagy via the miR-150-5p-DRP 1 axis, which sheds light on a novel mechanism of DN.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , MicroRNAs , RNA Longo não Codificante , Diabetes Mellitus/metabolismo , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/metabolismo , Dinaminas , Células Epiteliais/metabolismo , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Mitofagia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
18.
Eur Radiol ; 31(7): 4548-4556, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33447859

RESUMO

OBJECTIVES: This study aimed to investigate the association between dilation and proliferation and anastomosis of perforating arteries, and intracranial hemorrhage in moyamoya disease (MMD) patients, using high-resolution magnetic resonance imaging (HRMRI). METHODS: Adult patients with MMD at advanced stages were prospectively enrolled and underwent HRMRI exams. Dilation and proliferation of the lenticulostriate artery (LSA), medullary artery, and anterior or posterior choroidal arteries (AChA or PChA) were assessed. Abnormal anastomoses were identified between (1) the LSA and the medullary or insular arteries; (2) the thalamo-geniculate, thalamo-tuberal, or thalamo-perforating arteries and the medullary or insular arteries; and (3) the AChA or PChA and the medullary or insular arteries. The association between these variables and hemorrhagic events was calculated using univariate and multivariate analyses. RESULTS: Fifty patients (14 men; mean age, 35.4 ± 9.7 years) were finally analyzed, including 17 hemorrhagic patients and 33 non-hemorrhagic patients. The inter-rater agreement for the qualitative evaluation of perforating arteries was good. Dilation and proliferation of the AChA or PChA (88.2% versus 54.5%, p = 0.027), and choroidal anastomosis (64.7% versus 18.2%, p = 0.002) were more frequently observed in patients with hemorrhage. Multivariate logistic regression showed that choroidal anastomosis remained significantly associated with hemorrhage (odds ratio = 5.95, 95% confidence interval = 1.21-29.25, p = 0.028). CONCLUSIONS: Choroidal anastomosis is independently associated with hemorrhagic events in adult patients with MMD at advanced stages. HRMRI can provide detailed information on both the anatomies and abnormal collaterals in MMD, which facilitates risk estimates of bleeding in MMD. KEY POINTS: • High-resolution magnetic resonance imaging allows for the evaluation of perforating arteries in patients with moyamoya disease. • Choroidal anastomosis is associated with hemorrhagic events in patients with moyamoya disease. • High-resolution magnetic resonance imaging might facilitate further grading and classification of moyamoya vessels.


Assuntos
Doença de Moyamoya , Adulto , Anastomose Cirúrgica , Biomarcadores , Angiografia Cerebral , Humanos , Hemorragias Intracranianas/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doença de Moyamoya/complicações , Doença de Moyamoya/diagnóstico por imagem
19.
Diabetes Obes Metab ; 23(8): 1754-1764, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33769656

RESUMO

AIM: To evaluate the efficacy and safety of henagliflozin in patients with type 2 diabetes mellitus (T2DM) inadequately controlled with metformin. MATERIAL AND METHODS: This multicentre phase 3 trial included a 24-week randomized, double-blind, placebo-controlled period, followed by a 28-week extension period. Patients with a glycated haemoglobin (HbA1c) level of 7.0% (53 mmol/mol) to 10.5% (91 mmol/mol) were randomized and treated with once-daily placebo (n = 161), henagliflozin 5 mg (n = 162), or henagliflozin 10 mg (n = 160). After 24 weeks, patients on placebo were switched to 5 mg or 10 mg henagliflozin for the additional 28-week treatment, and patients on henagliflozin during 24-week treatment period maintained this initial therapy. The primary endpoint was change in HbA1c from baseline to Week 24. RESULTS: At Week 24, the least squares mean HbA1c changes versus placebo from baseline were - 0.76% (-8.3 mmol/mol) and - 0.80% (-8.7 mmol/mol) for henagliflozin 5 and 10 mg, respectively (all P < 0.0001). Compared with the placebo group, both doses of henagliflozin lowered fasting plasma glucose, 2-hour postprandial plasma glucose, body weight and blood pressure, and increased the proportions of patients achieving HbA1c <7.0% (53 mmol/mol) at Week 24. The trends in these improvements were sustained over an additional 28 weeks. Slightly higher proportions of ketosis and presence of urine ketone bodies were observed in patients treated with henagliflozin compared to placebo at Week 24. No diabetic ketoacidosis or episodes of severe hypoglycaemia were reported. CONCLUSIONS: Henagliflozin 5 mg or 10 mg as add-on therapy to metformin provided a new therapeutic option for the treatment of T2DM patients who have inadequate glycaemic control with metformin alone, and was generally well tolerated.


Assuntos
Diabetes Mellitus Tipo 2 , Metformina , Glicemia , Compostos Bicíclicos Heterocíclicos com Pontes , Diabetes Mellitus Tipo 2/tratamento farmacológico , Método Duplo-Cego , Quimioterapia Combinada , Hemoglobinas Glicadas/análise , Humanos , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Resultado do Tratamento
20.
Org Biomol Chem ; 19(41): 8940-8946, 2021 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-34617948

RESUMO

Berninamycins are a class of thiopeptide antibiotics with potent activity against Gram-positive bacteria. Heterologous expression of the berninamycin (ber) biosynthetic gene cluster from marine-derived Streptomyces sp. SCSIO 11878 in different terrestrial model Streptomyces hosts led to the production of berninamycins A (1) and B (2) in Streptomyces lividans SBT18 and Streptomyces coelicolor M1154, while two new linearized berninamycins J (3) and K (4) were obtained in Streptomyces albus J1074. Their structures were elucidated by detailed interpretation of NMR data and Marfey's method. Bioactivity assays showed that the linear thiopeptides 3 and 4 were less potent than 1 and 2 in antibacterial activity. This work indicates that undefined host-dependent enzymes might be responsible for generating the linear thiopeptides 3 and 4 in S. albus J1074.


Assuntos
Antibacterianos
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