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1.
Environ Sci Technol ; 58(25): 11096-11104, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38865480

RESUMO

Hydrogen peroxide (H2O2) plays a crucial role as an oxidizing agent within the tropospheric environment, making a substantial contribution to sulfate formation in hydrated aerosols and cloud and fog droplets. Field observations show that high levels of H2O2 are often observed in heavy haze events and polluted air. However, the source of H2O2 remains unclear. Here, using the droplets formed in situ by the deliquescence of hygroscopic compounds under a high relative humidity (RH), the formation of H2O2 by the photochemistry of imidazole-2-carbaldehyde (2-IC) under ultraviolet irradiation was explored. The results indicate that 2-IC produces IM-C•-OH and IM-C•═O radicals via H transfer itself to its excited triplet state and generates H2O2 and organic peroxides in the presence of O2, which has an evident oxidizing effect on SO2, suggesting the potential involvement of this pathway in the formation of atmospheric sulfate. H2O2 formation is limited in acidic droplets or droplets containing ammonium ions, and no H2O2 is detected in droplets containing nitrate, whereas droplets containing citric acid have an obvious promotion effect on H2O2 formation. These findings provide valuable insights into the behaviors of atmospheric photosensitizers, the source of H2O2, and the formation of sulfate in atmospheric droplets.


Assuntos
Peróxido de Hidrogênio , Oxirredução , Peróxido de Hidrogênio/química , Imidazóis/química , Fotoquímica , Dióxido de Enxofre/química , Poluentes Atmosféricos/química , Raios Ultravioleta
2.
BMC Ophthalmol ; 24(1): 206, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38711059

RESUMO

PURPOSE: The main objective is to quantify the lens nuclear opacity using spectral-domain optical coherence tomography (SD-OCT) and to evaluate its association with Lens Opacities Classification System III (LOCS-III) system, lens thickness (LT), and surgical parameters. The secondary objective is to assess the diagnostic model performance for hard nuclear cataract. METHODS: This study included 70 eyes of 57 adults with cataract, with 49 (70%) and 21 (30%) in training and validation cohort, respectively. Correlations of the average nuclear density (AND) /maximum nuclear density (MND) with LOCS-III scores, LT, and surgical parameters were analyzed. Univariate and multivariate logistic regression analysis, receiver operating characteristic curves and calibration curves were performed for the diagnostic of hard nuclear cataract. RESULTS: The pre-operative uncorrected distance visual acuity (UDVA), intraocular pressure (IOP), mean axial length (AL), and LT were 1.20 ± 0.47 log MAR, 15.50 ± 2.87 mmHg, 27.34 ± 3.77 mm and 4.32 ± 0.45 mm, respectively. The average nuclear opalescence (NO) and nuclear colour (NC) scores were 3.61 ± 0.94 and 3.50 ± 0.91 (ranging from 1.00 to 6.90), respectively. The average AND and MND were 137.94 ± 17.01 and 230.01 ± 8.91, respectively. NC and NO scores both significantly correlated with the AND (rNC = 0.733, p = 0.000; rNO = 0.755, p = 0.000) and MND (rNC = 0.643, p = 0.000; rNO = 0.634, p = 0.000). In the training cohort, the area under the curve (AUC) of the model was 0.769 (P < 0.001, 95%CI 0.620-0.919), which had a good degree of differentiation (Fig. 2a). The calibration curve showed good agreement between predicted and actual probability. CONCLUSION: The nuclear density measurement on SD-OCT images can serve as an objective and reliable indicator for quantifying nuclear density.


Assuntos
Catarata , Núcleo do Cristalino , Tomografia de Coerência Óptica , Acuidade Visual , Humanos , Feminino , Masculino , Tomografia de Coerência Óptica/métodos , Catarata/diagnóstico , Idoso , Pessoa de Meia-Idade , Núcleo do Cristalino/patologia , Núcleo do Cristalino/diagnóstico por imagem , Acuidade Visual/fisiologia , Curva ROC , Estudos Retrospectivos , Facoemulsificação , Idoso de 80 Anos ou mais , Adulto , Cristalino/diagnóstico por imagem , Cristalino/patologia
3.
J Med Virol ; 95(3): e28637, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36892175

RESUMO

Increasing evidence suggests that natural antisense transcriptional lncRNAs regulate their adjacent coding genes to mediate diverse aspects of biology. Bioinformatics analysis of the previously identified antiviral gene ZNFX1 revealed neighboring lncRNA ZFAS1 transcribed on the opposite strand from ZNFX1. Whether ZFAS1 exerts antiviral function via regulating the dsRNA sensor ZNFX1 is unknown. Here we found that ZFAS1 was upregulated by RNA and DNA viruses and type I IFNs (IFN-I) dependent on Jak-STAT signaling, similar to the transcription regulation of ZNFX1. Knockdown of endogenous ZFAS1 partially facilitated viral infection, while ZFAS1 overexpression showed opposite effects. In addition, mice were more resistant to VSV infection with the delivery of human ZFAS1. We further observed that ZFAS1 knockdown significantly inhibited IFNB1 expression and IFR3 dimerization, whereas ZFAS1 overexpression positively regulated antiviral innate immune pathways. Mechanistically, ZFAS1 positively regulated ZNFX1 expression and antiviral function by enhancing the protein stability of ZNFX1, thereby establishing a positive feedback loop to enhance antiviral immune activation status. In short, ZFAS1 is a positive regulator of antiviral innate immune response via regulating its neighbor gene ZNFX1, adding new mechanistic insight into lncRNA-mediated regulation of signaling in innate immunity.


Assuntos
MicroRNAs , RNA Longo não Codificante , Humanos , Animais , Camundongos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Regulação da Expressão Gênica , Imunidade Inata , Antivirais , MicroRNAs/genética , Antígenos de Neoplasias
4.
Acta Pharmacol Sin ; 44(9): 1867-1878, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37142684

RESUMO

Inhibition of NLRP3 inflammasome activation produces potent therapeutic effects in a wide array of inflammatory diseases. Bergapten (BeG), a furocoumarin phytohormone present in many herbal medicines and fruits, exibits anti-inflammatory activity. In this study we characterized the therapeutic potential of BeG against bacterial infection and inflammation-related disorders, and elucidated the underlying mechanisms. We showed that pre-treatment with BeG (20 µM) effectively inhibited NLRP3 inflammasome activation in both lipopolysaccharides (LPS)-primed J774A.1 cells and bone marrow-derived macrophages (BMDMs), evidenced by attenuated cleaved caspase-1 and mature IL-1ß release, as well as reduced ASC speck formation and subsequent gasdermin D (GSDMD)-mediated pyroptosis. Transcriptome analysis revealed that BeG regulated the expression of genes involved in mitochondrial and reactive oxygen species (ROS) metabolism in BMDMs. Moreover, BeG treatment reversed the diminished mitochondrial activity and ROS production after NLRP3 activation, and elevated the expression of LC3-II and enhanced the co-localization of LC3 with mitochondria. Treatment with 3-methyladenine (3-MA, 5 mM) reversed the inhibitory effects of BeG on IL-1ß, cleaved caspase-1 and LDH release, GSDMD-N formation as well as ROS production. In mouse model of Escherichia coli-induced sepsis and mouse model of Citrobacter rodentium-induced intestinal inflammation, pre-treatment with BeG (50 mg/kg) significantly ameliorated tissue inflammation and injury. In conclusion, BeG inhibits NLRP3 inflammasome activation and pyroptosis by promoting mitophagy and maintaining mitochondrial homeostasis. These results suggest BeG as a promising drug candidate for the treatment of bacterial infection and inflammation-related disorders.


Assuntos
Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Camundongos , Animais , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Piroptose , Espécies Reativas de Oxigênio/metabolismo , 5-Metoxipsoraleno/farmacologia , Mitofagia , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Caspase 1/metabolismo , Interleucina-1beta/metabolismo
5.
Acta Pharmacol Sin ; 44(11): 2253-2264, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37311796

RESUMO

Although STAT3 has been reported as a negative regulator of type I interferon (IFN) signaling, the effects of pharmacologically inhibiting STAT3 on innate antiviral immunity are not well known. Capsaicin, approved for the treatment of postherpetic neuralgia and diabetic peripheral nerve pain, is an agonist of transient receptor potential vanilloid subtype 1 (TRPV1), with additional recognized potencies in anticancer, anti-inflammatory, and metabolic diseases. We investigated the effects of capsaicin on viral replication and innate antiviral immune response and discovered that capsaicin dose-dependently inhibited the replication of VSV, EMCV, and H1N1. In VSV-infected mice, pretreatment with capsaicin improved the survival rate and suppressed inflammatory responses accompanied by attenuated VSV replication in the liver, lung, and spleen. The inhibition of viral replication by capsaicin was independent of TRPV1 and occurred mainly at postviral entry steps. We further revealed that capsaicin directly bound to STAT3 protein and selectively promoted its lysosomal degradation. As a result, the negative regulation of STAT3 on the type I IFN response was attenuated, and host resistance to viral infection was enhanced. Our results suggest that capsaicin is a promising small-molecule drug candidate, and offer a feasible pharmacological strategy for strengthening host resistance to viral infection.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Interferon Tipo I , Infecções por Orthomyxoviridae , Camundongos , Animais , Capsaicina/farmacologia , Fator de Transcrição STAT3 , Transdução de Sinais , Proteínas de Transporte , Replicação Viral
6.
Nano Lett ; 22(4): 1587-1594, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35129992

RESUMO

A spectrum-resolved photon detector is crucial for cutting-edge quantum optics, astronomical observation, and spectroscopic sensing. However, such an ability is rarely obtained because a direct linear conversion from weak single-photon energy to a readable electrical signal above the noise level without causing an avalanche is challenging. Here, we overcame these difficulties by building a probabilistic energy-to-amplitude mapping in a tapered superconducting nanowire single-photon detector and combining a computational reconstruction to obtain equivalent spectral resolving capacity. Distinguished dependence of pulse amplitude distributions on varied input spectra has been observed experimentally. As the energy-to-amplitude mapping is probabilistic, statistical measurements are required. By collecting around a few hundred photons, we have demonstrated wavelength perception over a wide spectral range from 600 to 1700 nm with a resolution of 100 nm. These findings represent a new approach to designing spectrum-sensitive SNSPDs for low-light spectroscopic applications.

7.
Med Res Rev ; 42(3): 1147-1178, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34877672

RESUMO

Andrographolide, a well-known natural lactone having a range of pharmacological actions in traditional Chinese medicine. It has long been used to cure a variety of ailments. In this review, we cover the pharmacokinetics and pharmacological activity of andrographolide which supports its further clinical application in cancers and inflammatory diseases. Growing evidence shows a good therapeutic effect in inflammatory diseases, including liver diseases, joint diseases, respiratory system diseases, nervous system diseases, heart diseases, inflammatory bowel diseases, and inflammatory skin diseases. As a result, the effects of andrographolide on immune cells and the processes that underpin them are discussed. The preclinical use of andrographolide to different organs in response to malignancies such as colorectal, liver, gastric, breast, prostate, lung, and oral cancers has also been reviewed. In addition, several clinical trials of andrographolide in inflammatory diseases and cancers have been summarized. This review highlights recent advances in ameliorating inflammatory diseases as well as cancers by andrographolide and its analogs, providing a new perspective for subsequent research of this traditional natural product.


Assuntos
Produtos Biológicos , Diterpenos , Neoplasias , Diterpenos/farmacologia , Diterpenos/uso terapêutico , Humanos , Neoplasias/tratamento farmacológico
8.
J Neurochem ; 161(1): 84-100, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34368959

RESUMO

Brain energetics disturbance is a hypothesized cause of depression. Glucose is the predominant fuel of brain energy metabolism; however, the cell-specific change of glucose metabolism and underlying molecular mechanism in depression remains unclear. In this study, we firstly applied 18 F-FDG PET and observed brain glucose hypometabolism in the prefrontal cortex (PFC) of corticosterone-induced depression of rats. Next, astrocytic glucose hypometabolism was identified in PFC slices in both corticosterone-induced depression of rats and cultured primary astrocytes from newborn rat PFC after stress-level corticosterone (100 nM) stimulation. Furthermore, we found the blockage of glucose uptake and the decrease of plasma membrane (PM) translocation of glucose transporter 1 (GLUT1) in astrocytic glucose hypometabolism under depressive condition. Interestingly, thioredoxin interacting protein (TXNIP), a glucose metabolism sensor and controller, was found to be over-expressed in corticosterone-stimulated astrocytes in vivo and in vitro. High TXNIP level could restrict GLUT1-mediated glucose uptake in primary astrocytes in vitro. Adeno-associated virus vector-mediated astrocytic TXNIP over-expression in rat medial PFC suppressed GLUT1 PM translocation, consequently developed depressive-like behavior. Conversely, TXNIP siRNA facilitated GLUT1 PM translocation to recover glucose hypometabolism in corticosterone-exposed cultured astrocytes. Notably, astrocyte-specific knockdown of TXNIP in medial PFC of rats facilitated astrocytic GLUT1 PM translocation, showing obvious antidepressant activity. These findings provide a new astrocytic energetic perspective in the pathogenesis of depression and, more importantly, provide TXNIP as a promising molecular target for novel depression therapy.


Assuntos
Astrócitos , Glucose , Animais , Astrócitos/metabolismo , Proteínas de Ciclo Celular , Corticosterona/metabolismo , Glucose/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Ratos , Tiorredoxinas/metabolismo
9.
Opt Lett ; 47(14): 3523-3526, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35838719

RESUMO

A superconducting nanowire single-photon imager (SNSPI) uses a time-multiplexing method to reduce the readout complexity. However, due to the serial connection, the nanowire should be uniform so that a common bias can set all segments of the nanowire to their maximum detection efficiency, which becomes more challenging as the scalability (i.e., the length of the nanowire) increases. Here, we have developed a 64-pixel SNSPI based on amorphous Mo80Si20 film, which yielded a uniform nanowire and slow transmission line. Adjacent detectors were separated by delay lines, giving an imaging field of 270 µm × 240 µm. Benefiting from the high kinetic inductance of Mo80Si20 films, the delay line gave a phase velocity as low as 4.6 µm/ps. The positions of all pixels can be read out with a negligible electrical cross talk of 0.02% by using cryogenic amplifiers. The timing jitter was 100.8 ps. Saturated internal quantum efficiency was observed at a wavelength of 1550 nm. These results demonstrate that amorphous film is a promising material for achieving SNSPIs with large scalability and high efficiency.

10.
Acta Pharmacol Sin ; 43(8): 1955-1969, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34983931

RESUMO

Paternal stress exposure-induced high corticosterone (CORT) levels may contribute to depression in offspring. Clinical studies disclose the association of depressive symptoms in fathers with their adolescent offspring. However, there is limited information regarding the intervention for intergenerational inheritance of depression. In this study we evaluated the intervention of cinnamaldehyde, a major constituent of Chinese herb cinnamon bark, for intergenerational inheritance of depression in CORT- and CMS-induced mouse models of depression. Depressive-like behaviors were induced in male mice by injection of CORT (20 mg·kg-1·d-1, sc) for 6 weeks or by chronic mild stress (CMS) for 6 weeks. We showed that co-administration of cinnamaldehyde (10, 20, or 40 mg·kg-1·d-1, ig) for 6 weeks in F0 males prevented the depressive-like phenotypes of F1 male offspring. In addition, co-administration of cinnamaldehyde (20 mg·kg-1·d-1, ig) for 4 weeks significantly ameliorated depressive-like behaviors of chronic variable stress (CVS)-stimulated F1 offspring born to CMS mice. Notably, cinnamaldehyde had no reproductive toxicity, while positive drug fluoxetine showed remarkable reproductive toxicity. We revealed that CMS and CORT significantly reduced testis glucocorticoid receptor (GR) expression, and increased testis and sperm miR-190b expression in F0 depressive-like models. Moreover, pre-miR-190b expression was upregulated in testis of F0 males. The amount of GR on miR-190b promoter regions was decreased in testis of CORT-stimulated F0 males. Cinnamaldehyde administration reversed CORT-induced GR reduction in testis, miR-190b upregulation in testis and sperm, pre-miR-190b upregulation in testis, and the amount of GR on miR-190b promoter regions of F0 males. In miR-190b-transfected Neuro 2a (N2a) cells, we demonstrated that miR-190b might directly bind to the 3'-UTR of brain-derived neurotrophic factor (BDNF). In the hippocampus of F1 males of CORT- or CMS-induced depressive-like models, increased miR-190b expression was accompanied by reduced BDNF and GR, which were ameliorated by cinnamaldehyde. In conclusion, cinnamaldehyde is a potential intervening agent for intergenerational inheritance of depression, probably by regulating GR/miR-190b/BDNF pathway.


Assuntos
Acroleína , Fator Neurotrófico Derivado do Encéfalo , Depressão , MicroRNAs , Receptores de Glucocorticoides , Acroleína/análogos & derivados , Acroleína/farmacologia , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Corticosterona/metabolismo , Depressão/tratamento farmacológico , Depressão/genética , Pai/psicologia , Hipocampo/metabolismo , Humanos , Masculino , Camundongos , MicroRNAs/metabolismo , Herança Paterna , Receptores de Glucocorticoides/metabolismo , Sêmen/metabolismo
11.
Nano Lett ; 21(22): 9625-9632, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34730364

RESUMO

Designing a spectrometer without the need for wavelength multiplexing optics can effectively reduce the complexity and physical footprint. On the basis of the computational spectroscopic strategy and combining a broadband-responsive dynamic detector, we successfully demonstrate an optics-free single-detector spectrometer that maps the tunable quantum efficiency of a superconducting nanowire into a matrix to build a solvable mathematical equation. Such a spectrometer can realize a broadband spectral responsivity ranging from 660 to 1900 nm. The spectral resolution at the telecom is sub-10 nm, exceeding the energy resolving capacity of existing infrared single-photon detectors. Meanwhile, benefiting from the optics-free setup, precise time-of-flight measurements can be simultaneously achieved. We have demonstrated a spectral LiDAR with eight spectral channels. This spectrometer scheme paves the way for applying superconducting nanowire detectors in multifunctional spectroscopy and represents a conceptual advancement for on-chip spectroscopy and spectral imaging.

12.
J Biol Chem ; 295(31): 10842-10856, 2020 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-32546483

RESUMO

Chronic low-grade inflammation plays an important role in the pathogenesis of type 2 diabetes. Src homology 2 domain-containing tyrosine phosphatase-2 (SHP2) has been reported to play diverse roles in different tissues during the development of metabolic disorders. We previously reported that SHP2 inhibition in macrophages results in increased cytokine production. Here, we investigated the association between SHP2 inhibition in macrophages and the development of metabolic diseases. Unexpectedly, we found that mice with a conditional SHP2 knockout in macrophages (cSHP2-KO) have ameliorated metabolic disorders. cSHP2-KO mice fed a high-fat diet (HFD) gained less body weight and exhibited decreased hepatic steatosis, as well as improved glucose intolerance and insulin sensitivity, compared with HFD-fed WT littermates. Further experiments revealed that SHP2 deficiency leads to hyperactivation of caspase-1 and subsequent elevation of interleukin 18 (IL-18) levels, both in vivo and in vitro Of note, IL-18 neutralization and caspase-1 knockout reversed the amelioration of hepatic steatosis and insulin resistance observed in the cSHP2-KO mice. Administration of two specific SHP2 inhibitors, SHP099 and Phps1, improved HFD-induced hepatic steatosis and insulin resistance. Our findings provide detailed insights into the role of macrophagic SHP2 in metabolic disorders. We conclude that pharmacological inhibition of SHP2 may represent a therapeutic strategy for the management of type 2 diabetes.


Assuntos
Gorduras na Dieta/efeitos adversos , Fígado Gorduroso , Resistência à Insulina , Interleucina-18/metabolismo , Macrófagos/enzimologia , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Animais , Gorduras na Dieta/farmacologia , Fígado Gorduroso/induzido quimicamente , Fígado Gorduroso/genética , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Interleucina-18/genética , Macrófagos/patologia , Camundongos , Camundongos Knockout , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética
13.
J Neurochem ; 157(6): 1979-1991, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33205422

RESUMO

Our previous studies showed that high fructose diet (HFrD)-driven gut dysbiosis caused fecal short-chain fatty acids (SCFAs) reduction and intestinal epithelial barrier (IEB) damage in mice, which might play an important role in hippocampal neuroinflammatory injury. Mulberroside A is reported to have neuroprotective effects in animal experiments, while the underlying mechanisms are not yet fully elucidated. Here, we investigated whether and how mulberroside A prevented HFrD-induced neuroinflammatory injury. HFrD-fed mice were treated orally with mulberroside A (20 and 40 mg/kg) for 8 weeks. Mulberroside A was found to inhibit hippocampal neuroinflammation and neurogenesis reduction in HFrD-fed mice. It reshaped gut dysbiosis, increased fecal and serum SCFAs contents, reactivated signaling of the colonic NLR family, pyrin domain containing 6 (NLRP6) inflammasome, and up-regulated Muc2 expression to prevent IEB damage, as well as subsequently, reduced serum endotoxin levels in this animal model. Additionally, mulberroside A inhibited oxidative stress in colon of HFrD-fed mice and hydrogen peroxide (H2 O2 )-stimulated Caco-2 cells. Blood-brain barrier (BBB) structure defects were also observed in HFrD-driven hippocampal neuroinflammatory injury of mice. Interestingly, mulberroside A maintained astrocyte morphology and up-regulated tight junction proteins to repair BBB structure defects in hippocampus dentate gyrus (DG). Our results demonstrated that mulberroside A was capable of preventing HFrD-induced damage of IEB and BBB in mice, which might contribute to the suppression of hippocampal neuroinflammatory injury.


Assuntos
Barreira Hematoencefálica/metabolismo , Açúcares da Dieta/toxicidade , Dissacarídeos/farmacologia , Frutose/toxicidade , Hipocampo/metabolismo , Mucosa Intestinal/metabolismo , Estilbenos/farmacologia , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/patologia , Células CACO-2 , Células Cultivadas , Açúcares da Dieta/administração & dosagem , Frutose/administração & dosagem , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
14.
Toxicol Appl Pharmacol ; 420: 115530, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33845055

RESUMO

Chronic Kidney Disease (CKD) is a serious threat to human health. In addition, kidney fibrosis is a key pathogenic intermediate for the progression of CDK. Moreover, excessive activation of fibroblasts is key to the development of kidney fibrosis and this process is difficult to control. Notably, fraxinellone is a natural compound isolated from Dictamnus dasycarpus and has a variety of pharmacological activities, including hepatoprotective, anti-inflammatory and anti-cancer effects. However, the effect of fraxinellone on kidney fibrosis is largely unknown. The present study showed that fraxinellone could alleviate folic acid-induced kidney fibrosis in mice in a dose dependent manner. Additionally, the results revealed that fraxinellone could effectively down-regulate the expression of CUGBP1, which was highly up-regulated in human and murine fibrotic renal tissues. Furthermore, expression of CUGBP1 was selectively induced by the Transforming Growth Factor-beta (TGF-ß) through p38 and JNK signaling in kidney fibroblasts. On the other hand, downregulating the expression of CUGBP1 significantly inhibited the activation of kidney fibroblasts. In conclusion, these findings demonstrated that fraxinellone might be a new drug candidate and CUGBP1 could be a promising target for the treatment of kidney fibrosis.


Assuntos
Benzofuranos/farmacologia , Proteínas CELF1/metabolismo , Fibroblastos/efeitos dos fármacos , Nefropatias/prevenção & controle , Rim/efeitos dos fármacos , Animais , Proteínas CELF1/genética , Linhagem Celular , Modelos Animais de Doenças , Fibroblastos/metabolismo , Fibroblastos/patologia , Fibrose , Ácido Fólico , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Rim/metabolismo , Rim/patologia , Nefropatias/induzido quimicamente , Nefropatias/metabolismo , Nefropatias/patologia , Masculino , Camundongos Endogâmicos C57BL , Ratos , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
15.
Nano Lett ; 20(5): 3553-3559, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32286838

RESUMO

Many classic and quantum devices need to operate at cryogenic temperatures, demanding advanced cryogenic digital electronics for processing the input and output signals on a chip to extend their scalability and performance. Here, we report a superconducting binary encoder with ultralow power dissipation and ultracompact size. We introduce a multigate superconducting nanowire cryotron (nTron) that functions as an 8-input OR gate within a footprint of approximately 0.5 µm2. Four cryotrons compose a 4-bit encoder that has a bias margin of 18.9%, an operation speed greater than 250 MHz, an average switching jitter of 75 ps, and a power dissipation of less than 1 µW. We apply this encoder to read out a superconducting-nanowire single-photon detector array whose pixel location is digitized into a 4-bit binary address. The small size of the nanowire combined with the low power dissipation makes nTrons promising for future monolithic integration.

16.
J Cell Mol Med ; 24(22): 13208-13222, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33058500

RESUMO

High fructose intake is a risk factor for liver fibrosis. Polydatin is a main constituent of the rhizome of Polygonum cuspidatum, which has been used in traditional Chinese medicine to treat liver fibrosis. However, the underlying mechanisms of fructose-driven liver fibrosis as well as the actions of polydatin are not fully understood. In this study, fructose was found to promote zinc finger E-box binding homeobox 1 (ZEB1) nuclear translocation, decrease microRNA-203 (miR-203) expression, increase survivin, activate transforming growth factor ß1 (TGF-ß1)/Smad signalling, down-regulate E-cadherin, and up-regulate fibroblast specific protein 1 (FSP1), vimentin, N-cadherin and collagen I (COL1A1) in rat livers and BRL-3A cells, in parallel with fructose-induced liver fibrosis. Furthermore, ZEB1 nuclear translocation-mediated miR-203 low-expression was found to target survivin to activate TGF-ß1/Smad signalling, causing the EMT in fructose-exposed BRL-3A cells. Polydatin antagonized ZEB1 nuclear translocation to up-regulate miR-203, subsequently blocked survivin-activated TGF-ß1/Smad signalling, which were consistent with its protection against fructose-induced EMT and liver fibrosis. These results suggest that ZEB1 nuclear translocation may play an essential role in fructose-induced EMT in liver fibrosis by targeting survivin to activate TGF-ß1/Smad signalling. The suppression of ZEB1 nuclear translocation by polydatin may be a novel strategy for attenuating the EMT in liver fibrosis associated with high fructose diet.


Assuntos
Transição Epitelial-Mesenquimal , Glucosídeos/farmacologia , Cirrose Hepática/metabolismo , Estilbenos/farmacologia , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo , Transporte Ativo do Núcleo Celular , Animais , Caderinas/metabolismo , Colágeno Tipo I/metabolismo , Cadeia alfa 1 do Colágeno Tipo I , Frutose , Cirrose Hepática/induzido quimicamente , Masculino , MicroRNAs/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Fator de Crescimento Transformador beta1/metabolismo
17.
Opt Lett ; 45(24): 6732-6735, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33325883

RESUMO

The quality of an image is limited to the signal-to-noise ratio of the output from sensors. As the background noise increases much more than the signal, which can be caused by either a huge attenuation of light pulses after a long-haul transmission or a blinding attack with a strong flood illumination, an imaging system stops working properly. Here we built a superconducting single-photon infrared camera of negligible dark counts and 60 ps timing resolution. Combining with an adaptive 3D slicing algorithm that gives each pixel an optimal temporal window to distinguish clustered signal photons from a uniformly distributed background, we successfully reconstructed 3D single-photon images at both a low signal level (∼1 average photon per pixel) and extremely high noise background (background-to-signal ratio = 200 within a period of 50 ns before denoising). Among all detection events, we were able to remove 99.45% of the noise photons while keeping the signal photon loss at 0.74%. This Letter is a direct outcome of quantum-inspired imaging that asks for a co-development of sensors and computational methods. We envision that the proposed methods can increase the working distance of a long-haul imaging system or defend it from blinding attacks.

18.
J Immunol ; 201(8): 2403-2413, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30185517

RESUMO

Aberrant activation of the NLRP3 inflammasome contributes to the onset and progression of various inflammatory diseases, making it a highly desirable drug target. In this study, we screened a series of small compounds with anti-inflammatory activities and identified a novel NLRP3 inflammasome inhibitor, AI-44, a curcumin analogue that selectively inhibited signal 2 but not signal 1 of NLRP3 inflammasome activation. We demonstrated that AI-44 bound to peroxiredoxin 1 (PRDX1) and promoted the interaction of PRDX1 with pro-Caspase-1 (CASP1), which led to the suppression of association of pro-CASP1 and ASC. Consequently, the assembly of the NLRP3 inflammasome was interrupted, and the activation of CASP1 was inhibited. Knockdown of PRDX1 significantly abrogated the inhibitory effect of AI-44 on the NLRP3 inflammasome. Importantly, AI-44 alleviated LPS-induced endotoxemia in mice via suppressing NLRP3 inflammasome activation. Taken together, our work highlighted PRDX1 as a negative regulator of NLRP3 inflammasome activation and suggested AI-44 as a promising candidate compound for the treatment of sepsis or other NLRP3 inflammasome-driven diseases.


Assuntos
Anti-Inflamatórios/uso terapêutico , Curcumina/uso terapêutico , Inflamassomos/metabolismo , Peroxirredoxinas/metabolismo , Sepse/tratamento farmacológico , Animais , Caspase 1/metabolismo , Curcumina/análogos & derivados , Modelos Animais de Doenças , Feminino , Humanos , Lipopolissacarídeos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Terapia de Alvo Molecular , Complexos Multiproteicos , Peroxirredoxinas/genética , RNA Interferente Pequeno/genética , Sepse/imunologia , Transdução de Sinais , Células THP-1
19.
Exp Cell Res ; 369(2): 304-315, 2018 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-29856990

RESUMO

BACKGROUND: CDK8 is associated with the transcriptional Mediator complex and has been shown to regulate several transcription factors implicated in cancer. As a pancreatic cancer oncogene, the role of CDK8 in cancer angiogenesis remains unclear. Here, we investigated the contribution of CDK8 in pancreatic cancer angiogenesis and examined the underlying molecular mechanisms. METHODS: CDK8 expression was evaluated via immunohistochemistry, western blotting, and qRT-PCR in relation to the clinicopathological characteristics of pancreatic cancer patients. The effects of silencing or overexpressing CDK8 on cancer angiogenesis were assessed in vitro by western blotting assays in pancreatic cancer cell lines and in vivo with nude mice xenograft models. RESULTS: Compared with adjacent normal tissues, pancreatic cancer tissues showed upregulation of CDK8 expression, which was inversely correlated with T grade, liver metastasis, size, lymph node metastasis and poor survival. CDK8 overexpression promoted angiogenesis in pancreatic cancer via activation of the CDK8-ß-catenin-KLF2 signaling axis, as demonstrated by the upregulation and downregulation of signals representing the rate-limiting steps in angiogenesis. Silencing CDK8 inhibited angiogenesis in pancreatic cancer in vitro. Additionally, these results were confirmed in nude mice xenograft models in vivo. CONCLUSIONS: CDK8 promotes angiogenesis in pancreatic cancer via activation of the CDK8-ß-catenin-KLF2 signaling axis, thus providing valid targets for the treatment of pancreatic cancer.


Assuntos
Quinase 8 Dependente de Ciclina/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Neovascularização Patológica/metabolismo , Neoplasias Pancreáticas/irrigação sanguínea , Neoplasias Pancreáticas/metabolismo , beta Catenina/metabolismo , Idoso , Animais , Linhagem Celular Tumoral , Quinase 8 Dependente de Ciclina/antagonistas & inibidores , Quinase 8 Dependente de Ciclina/genética , Feminino , Técnicas de Silenciamento de Genes , Xenoenxertos , Humanos , Fatores de Transcrição Kruppel-Like/antagonistas & inibidores , Fatores de Transcrição Kruppel-Like/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Neovascularização Patológica/genética , Neoplasias Pancreáticas/genética , RNA Interferente Pequeno/genética , Transdução de Sinais , Regulação para Cima , beta Catenina/antagonistas & inibidores , beta Catenina/genética
20.
Acta Pharmacol Sin ; 40(7): 879-894, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30568253

RESUMO

Increasing evidence has demonstrated that excessive fructose intake induces liver fibrosis. Epithelial-mesenchymal transition (EMT) driven by transforming growth factor-ß1 (TGF-ß1)/mothers against decapentaplegic homolog (Smad) signaling activation promotes the occurrence and development of liver fibrosis. Magnesium isoglycyrrhizinate is clinically used as a hepatoprotective agent to treat liver fibrosis, but its underlying molecular mechanism has not been identified. Using a rat model, we found that high fructose intake reduced microRNA (miR)-375-3p expression and activated the janus-activating kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) cascade and TGF-ß1/Smad signaling, which is consistent with the EMT and liver fibrosis. To further verify these observations, BRL-3A cells and/or primary rat hepatocytes were exposed to high fructose and/or transfected with a miR-375-3p mimic or inhibitor or treated with a JAK2 inhibitor, and we found that the low expression of miR-375-3p could induce the JAK2/STAT3 pathway to activate TGF-ß1/Smad signaling and promote the EMT. Magnesium isoglycyrrhizinate was found to ameliorate high fructose-induced EMT and liver fibrosis in rats. More importantly, magnesium isoglycyrrhizinate increased miR-375-3p expression to suppress the JAK2/STAT3 pathway and TGF-ß1/Smad signaling in these animal and cell models. This study provides evidence showing that magnesium isoglycyrrhizinate attenuates liver fibrosis associated with a high fructose diet.


Assuntos
Cirrose Hepática/tratamento farmacológico , MicroRNAs/metabolismo , Saponinas/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Triterpenos/uso terapêutico , Animais , Linhagem Celular , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Frutose , Janus Quinase 2/metabolismo , Cirrose Hepática/induzido quimicamente , Masculino , Ratos Sprague-Dawley , Fator de Transcrição STAT3/metabolismo , Saponinas/farmacologia , Proteínas Smad Reguladas por Receptor/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Triterpenos/farmacologia
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