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1.
J Am Chem Soc ; 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38943576

RESUMO

Manipulating single electrons at the atomic scale is vital for mastering complex surface processes governed by the transfer of individual electrons. Polarons, composed of electrons stabilized by electron-phonon coupling, offer a pivotal medium for such manipulation. Here, using scanning tunneling microscopy and spectroscopy (STM/STS) and density functional theory (DFT) calculations, we report the identification and manipulation of a new type of polaron, dubbed van der Waals (vdW) polaron, within mono- to trilayer ultrathin films composed of Sb2O3 molecules that are bonded via vdW attractions. The Sb2O3 films were grown on a graphene-covered SiC(0001) substrate via molecular beam epitaxy. Unlike prior molecular polarons, STM imaging observed polarons at the interstitial sites of the molecular film, presenting unique electronic states and localized band bending. DFT calculations revealed the lowest conduction band as an intermolecular bonding state, capable of ensnaring an extra electron through locally diminished intermolecular distances, thereby forming an intermolecular vdW polaron. We also demonstrated the ability to generate, move, and erase such vdW polarons using an STM tip. Our work uncovers a new type of polaron stabilized by coupling with intermolecular vibrations where vdW interactions dominate, paving the way for designing atomic-scale electron transfer processes and enabling precise tailoring of electron-related properties and functionalities.

2.
Plant Cell Environ ; 47(6): 2163-2177, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38481060

RESUMO

Copper (Cu) is an essential micronutrient for all living organisms but is also highly toxic in excess. Cellular homoeostasis of Cu is maintained by various transporters and metallochaperones. Here, we investigated the biological function of OsCOPT7, a member of the copper transporters (COPT) family, in Cu homoeostasis in rice. OsCOPT7 was mainly expressed in the roots and the expression was upregulated by Cu deficiency. OsCOPT7 was localized at the tonoplast and the endoplasmic reticulum. Knockout of OsCOPT7 increased Cu accumulation in the roots but decreased Cu concentrations in the shoots and grain. The knockout mutants contained higher concentrations of Cu in the roots cell sap but markedly lower concentrations of Cu in the xylem sap than wild-type plants. Seed setting and grain yield were reduced significantly in the knockout mutants grown in a low Cu soil. Knockout mutants were more tolerant to Cu toxicity. Yeast two-hybrid and bimolecular fluorescence complementation assays showed that OsCOPT7 interacts physically with the rice Cu chaperone antioxidant protein 1 (OsATX1). Taken together, our results indicate that OsCOPT7 is a specific Cu transporter functioning to export Cu from the vacuoles and the ER and plays an important role in controlling the root-to-shoot Cu translocation in rice.


Assuntos
Cobre , Retículo Endoplasmático , Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Transporte Biológico , Proteínas de Transporte de Cátions/metabolismo , Proteínas de Transporte de Cátions/genética , Cobre/metabolismo , Grão Comestível/metabolismo , Grão Comestível/genética , Retículo Endoplasmático/metabolismo , Técnicas de Inativação de Genes , Oryza/metabolismo , Oryza/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Sementes/metabolismo , Sementes/genética , Vacúolos/metabolismo
3.
J Fluoresc ; 33(3): 923-932, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36527543

RESUMO

Two chromenoquinoline-based fluorescent probes 1a-b have been synthesized and investigated. Photofading behaviors of compounds 1a-b showed that at least 89% absorption remained after 6 h irradiating, meanwhile, many of ions and amino acids had negligible impacts on their fluorescence intensity, which meant they had excellent photostability and selectivity. Probes 1a-b exhibited strong absorption and emission in organic solvents with large fluorescence quantum yields, even in water probe 1a still had a relatively large fluorescence quantum yield (20%). Combined with DFT calculation, the influence of alkylation on optical properties of 1b was elucidated. In addition, the fluorescence intensity of probe 1b with red emission enhanced by 5.4-fold and 5.3-fold after DNA and RNA added, and the fluorescence quantum yield increased from 3% to 17% and 14%, respectively, but the neutral molecule 1a had no response to nucleic acid. Furthermore, confocal microscopy imaging of probes 1a-b showed that 1a targeted lipid droplets while the methylated probe 1b to nucleus in living HeLa cells. The results indicated that the subcellular targeting zone could be changed by alkylation of nitrogen atom on chromenoquinoline-based conveniently, which provided a new idea for designing and synthesizing new subcellular labeled probes.


Assuntos
Corantes Fluorescentes , Ácidos Nucleicos , Humanos , Células HeLa , Corantes Fluorescentes/química , Diagnóstico por Imagem , Fluorescência
4.
Acta Pharmacol Sin ; 44(2): 393-405, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35922553

RESUMO

Dysregulation in lipid metabolism is the leading cause of chronic kidney disease (CKD) and also the important risk factors for high morbidity and mortality. Although lipid abnormalities were identified in CKD, integral metabolic pathways for specific individual lipid species remain to be clarified. We conducted ultra-high-performance liquid chromatography-high-definition mass spectrometry-based lipidomics and identified plasma lipid species and therapeutic effects of Rheum officinale in CKD rats. Adenine-induced CKD rats were administered Rheum officinale. Urine, blood and kidney tissues were collected for analyses. We showed that exogenous adenine consumption led to declining kidney function in rats. Compared with control rats, a panel of differential plasma lipid species in CKD rats was identified in both positive and negative ion modes. Among the 50 lipid species, phosphatidylcholine (PC), lysophosphatidylcholine (LysoPC) and lysophosphatidic acid (LysoPA) accounted for the largest number of identified metabolites. We revealed that six PCs had integral metabolic pathways, in which PC was hydrolysed into LysoPC, and then converted to LysoPA, which was associated with increased cytosolic phospholipase A2 protein expression in CKD rats. The lower levels of six PCs and their corresponding metabolites could discriminate CKD rats from control rats. Receiver operating characteristic curves showed that each individual lipid species had high values of area under curve, sensitivity and specificity. Administration of Rheum officinale significantly improved impaired kidney function and aberrant PC metabolism in CKD rats. Taken together, this study demonstrates that CKD leads to PC metabolism disorders and that the dysregulation of PC metabolism is involved in CKD pathology.


Assuntos
Insuficiência Renal Crônica , Ratos , Animais , Insuficiência Renal Crônica/tratamento farmacológico , Fosfatidilcolinas/efeitos adversos , Metabolismo dos Lipídeos , Adenina/uso terapêutico , Fosfolipases/efeitos adversos , Fosfolipases/metabolismo
5.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(8): 837-842, 2023 Aug 15.
Artigo em Zh | MEDLINE | ID: mdl-37668032

RESUMO

OBJECTIVES: To investigate the clinical characteristics, pathology, and prognosis of children with diffuse endocapillary proliferative Henoch-Schönlein purpura nephritis (DEP-HSPN). METHODS: A retrospective analysis was performed on the clinical, pathological, and prognosis data of 44 children with DEP-HSPN and 765 children without DEP-HSPN. The children with DEP-HSPN were diagnosed by renal biopsy in Jiangxi Provincial Children's Hospital from January 2006 to December 2021. RESULTS: Among the 809 children with purpura nephritis, 44 (5.4%) had DEP-HSPN, with a mean age of (8±3) years, and there were 29 boys (65.9%) and 15 girls (34.1%). Compared with the non-DEP-HSPN group, the DEP-HSPN group had a significantly shorter time from onset to renal biopsy and a significantly higher proportion of children with respiratory infection or gross hematuria, and most children had nephrotic syndrome. The DEP-HSPN group had significantly higher levels of 24-hour urinary protein, urinary protein grading, microscopic hematuria grading, serum creatinine, and blood urea nitrogen and significantly lower levels of serum albumin and complement C3 (P<0.05). The DEP-HSPN group had a higher pathological grading, with predominant deposition of IgA in the mesangial area and capillary loops, and higher activity scores in the modified semi-quantitative scoring system (P<0.05). The Kaplan-Meier survival analysis showed that there was no significant difference in the renal complete remission rate between the two groups (P>0.05). CONCLUSIONS: Children with DEP-HSPN have a rapid onset, severe clinical manifestations and pathological grading, and high activity scores in the modified semi-quantitative scoring system. However, most of the children with DEP-HSPN have a good prognosis, with a comparable renal complete remission rate to the children without DEP-HSPN.


Assuntos
Vasculite por IgA , Nefrite , Masculino , Feminino , Humanos , Criança , Pré-Escolar , Hematúria , Estudos Retrospectivos , Prognóstico
6.
Metabolomics ; 18(9): 71, 2022 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-36036299

RESUMO

INTRODUCTION: Solitary pulmonary nodules (SPNs) are commonly found in imaging technologies, but are plagued by high false-positive rates. OBJECTIVE: We aimed to identify metabolic alterations in SPN etiology and diagnosis using less invasive plasma metabolomics and lipidomics. METHODS: In total, 1160 plasma samples were obtained from healthy volunteers (n = 280), benign SPNs (n = 157) and malignant SPNs (stage I, n = 723) patients enrolled from 5 independent centers. Gas chromatography-triple quadrupole mass spectrometry (GC‒MS) and liquid chromatography-Q Exactive Hybrid Quadrupole-Orbitrap mass spectrometry (LC‒MS) were used to analyze the samples for untargeted metabolomics and lipidomics. RESULTS AND CONCLUSION: GC‒MS-based metabolomics revealed 1336 metabolic features, while LC‒MS-based lipidomics revealed 6088 and 2542 lipid features in the positive and negative ion modes, respectively. The metabolic and lipidic characteristics of healthy vs. benign or malignant SPNs exhibited substantial pattern differences. Of note, benign and malignant SPNs had no significant variations in circulating metabolic and lipidic markers and were validated in four other centers. This study demonstrates evidence of early metabolic alterations that can possibly distinguish SPNs from healthy controls, but not between benign and malignant SPNs.


Assuntos
Neoplasias Pulmonares , Nódulo Pulmonar Solitário , Diagnóstico Diferencial , Humanos , Lipidômica , Metabolômica
7.
Acta Pharmacol Sin ; 43(10): 2609-2623, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35347248

RESUMO

Renal fibrosis is an unavoidable end result of all forms of progressive chronic kidney diseases (CKD). Discovery of efficacious drugs against renal fibrosis is in crucial need. In a preliminary study we found that a derivative of artemisinin, dihydroartemisinin (DHA), exerted strong renoprotection, and reversed renal fibrosis in adenine-induced CKD mouse model. In this study we investigated the anti-fibrotic mechanisms of DHA, particularly its specific target in renal cells. Renal fibrosis was induced in mice by unilateral ureteral obstruction (UUO) or oral administration of adenine (80 mg · kg-1), the mice received DHA (30 mg · kg-1 · d-1, i.g.) for 14 or 21 days, respectively. We showed that DHA administration markedly attenuated the inflammation and fibrotic responses in the kidneys and significantly improved the renal function in both the renal fibrosis mouse models. In adenine-treated mice, DHA was more effective than 5-azacytidine against renal fibrosis. The anti-fibrotic effects of DHA were also observed in TGF-ß1-treated HK-2 cells. In order to determine the target protein of DHA, we conducted pull-down technology coupled with shotgun proteomics using a small-molecule probe based on the structure of DHA (biotin-DHA). As a results, DNA methyltransferase 1 (DNMT1) was identified as the anti-fibrotic target of DHA in 3 different types of renal cell lines (HK-2, HEK293 and 3T3). We demonstrated that DHA directly bound to Asn 1529 and Thr 1528 of DNMT1 with a Kd value of 8.18 µM. In primary mouse renal tubular cells, we showed that DHA (10 µM) promoted DNMT1 degradation via the ubiquitin-proteasome pathway. DHA-reduced DNMT1 expression effectively reversed Klotho promoter hypermethylation, which led to the reversal of Klotho protein loss in the kidney of UUO mice. This subsequently resulted in inhibition of the Wnt/ß-catenin and TGF-ß/Smad signaling pathways and consequently conferred renoprotection in the animals. Knockdown of Klotho abolished the renoprotective effect of DHA in UUO mice. Our study reveals a novel pharmacological activity for DHA, i.e., renoprotection. DHA exhibits this effect by targeting DNMT1 to reverse Klotho repression. This study provides an evidence for the possible clinical application of DHA in the treatment of renal fibrosis.


Assuntos
Artemisininas , Rim , Insuficiência Renal Crônica , Obstrução Ureteral , Adenina/farmacologia , Animais , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Azacitidina/metabolismo , Azacitidina/farmacologia , Azacitidina/uso terapêutico , Biotina/metabolismo , Biotina/farmacologia , Biotina/uso terapêutico , DNA/metabolismo , Metilases de Modificação do DNA/antagonistas & inibidores , Metilases de Modificação do DNA/metabolismo , Fibrose , Glucuronidase/genética , Células HEK293 , Humanos , Rim/patologia , Proteínas Klotho/efeitos dos fármacos , Proteínas Klotho/metabolismo , Camundongos , Complexo de Endopeptidases do Proteassoma/metabolismo , Insuficiência Renal Crônica/induzido quimicamente , Insuficiência Renal Crônica/tratamento farmacológico , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Ubiquitinas/metabolismo , Ubiquitinas/farmacologia , Ubiquitinas/uso terapêutico , Obstrução Ureteral/tratamento farmacológico , beta Catenina/metabolismo
8.
J Org Chem ; 86(13): 9206-9217, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34126743

RESUMO

An unprecedented catalyst-free reaction of benzo[b]thiophene-2,3-diones with difluoroenoxysilanes has been developed using either MeOH or H2O as the solvent, which constitutes a facile and efficient protocol for the solvent-controlled divergent synthesis of five- and seven-membered S-heterocycles featuring a gem-difluoromethylene group. A gram-scale synthesis and the diversification of the product transformations to other difluorinated S-heterocycles further highlight its utility.


Assuntos
Solventes , Catálise
9.
Bioorg Med Chem ; 46: 116390, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34500186

RESUMO

In order to discover antiplatelet drug with novel structure and expand our research scope, total twenty 1,3-benzenedisulfonyl piperazines, were designed and synthesized. These target compounds were divided into two series, namely 4-methoxy-1,3-benzenedisulfonyl piperazines of series 1 and 4-ethoxy-1,3-benzenedisulfonyl piperazines of series 2. With adenosine diphosphate (ADP), arachidonic acid (AA) and collagen as inducers, respectively, the Born turbidimetric method was used to screen the antiplatelet activity in vitro of all target compounds at a concentration of 1.3 µM, with aspirin and picotamide as positive control drugs. And of which, the activities of five compounds for collagen were higher than both picotamide and aspirin. In ADP or AA channel, compounds with an inhibition rate greater than 33% were selected, and their corresponding IC50 values were obtained. According to the IC50, the in vitro activity of one compound for ADP was higher than picotamide, and for AA, two compounds were higher than two positive control drugs and other two compounds only higher than or equal to aspirin. The preliminary analysis of the structure-activity relationship of the target compounds involved in this study was completed. Further, eight compounds exhibiting higher activity in one or two test channels, were subjected to cytotoxicity test on mouse fibroblasts (L929) by CCK-8 method. The in vitro cytotoxicity of most test compounds showed less than or same to control drug picotamide at 10 µM, but at the higher concentration of 100 µM, merely two compounds exhibited higher cell survival rate than that of picotamide. In addition, compound N1,N3-di(4-ethoxy-1,3-phenylenedisulfonyl)bis(1-(m-tolyl)piperazine), which is delivery activity in the three test channels, and another compound N1,N3-di(4-methoxy-1,3-phenylenedisulfonyl)bis(1-(m-tolyl)piperazine), which has the lowest cytotoxic in vitro compound among series 1 and series 2, respectively, are found and selected for simulation analysis as two most likely to dock with the receptor P2Y12. Each of synthesized compounds in silico molecular property and ADME (absorption, distribution, metabolism and excretion) are predicted by using Molinspiration property engine v2018.10 and PreADMET online servers, respectively. Compared with other series of compounds in the previous stage, the two series compounds obtained after the introduction of piperazinyl have a similar in vitro activity.


Assuntos
Fibroblastos/efeitos dos fármacos , Piperazinas/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Camundongos , Estrutura Molecular , Piperazinas/síntese química , Piperazinas/química , Inibidores da Agregação Plaquetária/síntese química , Inibidores da Agregação Plaquetária/química , Relação Estrutura-Atividade
10.
Biotechnol Lett ; 43(12): 2273-2281, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34669078

RESUMO

OBJECTIVES: Corynebacterium glutamicum (C. glutamicum) has been harnessed for multi-million-ton scale production of glutamate and lysine. To further increase its amino acid production for fermentation industry, there is an acute need to develop next-generation genome manipulation tool for its metabolic engineering. All reported methods for genome editing triggered with CRISPR-Cas are based on the homologous recombination. While, it requires the generation of DNA repair template, which is a bottle-neck for its extensive application. RESULTS: In this study, we developed a method for gene knockout in C. glutamicum via CRISPR-Cpf1-coupled non-homologous end-joining (CC-NHEJ). Specifically, CRISPR-Cpf1 introduced double-strand breaks in the genome of C. glutamicum, which was further repaired by ectopically expressed two NHEJ key proteins (Mycobacterium tuberculosis Ku and ligase D). We provide the proof of concept, for CC-NHEJ, by the successful knockout of the crtYf/e gene in C. glutamicum with the efficiency of 22.00 ± 5.56%, or something like that. CONCLUSION: The present study reported a novel genome manipulation method for C. glutamicum.


Assuntos
Sistemas CRISPR-Cas/genética , Corynebacterium glutamicum/genética , Reparo do DNA por Junção de Extremidades/genética , Engenharia Metabólica , Corynebacterium glutamicum/metabolismo , Edição de Genes , Técnicas de Inativação de Genes , Genoma Bacteriano/genética , Ácido Glutâmico/biossíntese , Autoantígeno Ku/genética , Lisina/biossíntese , Mycobacterium tuberculosis/genética
11.
Water Sci Technol ; 84(7): 1608-1622, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34662300

RESUMO

The effect of high voltage electrostatic field and high voltage alternating current electric field on the heat exchanger surface fouling under the conditions of hard water was investigated. The Ca2+ concentration in two water conditions was 12 mmol/L. The Mg2+ concentration was 10 mmol/L and 12 mmol/L respectively. The HCO3- concentration changed with the Mg2+ concentration. X-ray diffraction and scanning electron microscope results confirmed that the main crystal phases of the scale samples consisted of calcite and aragonite. The high voltage electrostatic treatment can promote scale growth under both water quality conditions. However, the high voltage alternating current electric field treatment shows a good scale inhibition effect under both water quality conditions, and the scale inhibition effect is best when both Ca2+ and Mg2+ concentrations are 12 mmol/L, and the average scale inhibition rate reaches 47.58%. When the calcite content of the scale sample is significantly higher than that of aragonite, Mg2+ affects the growth and solubility of crystals. Conversely, the high voltage alternating current electric field treatment can effectively extend the fouling induction period of the adherent scale on the heat exchanger surface, which is favorable for heat exchanger fouling.


Assuntos
Temperatura Alta , Água , Eletricidade , Transição de Fase , Eletricidade Estática
12.
J Infect Dis ; 222(1): 38-43, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32348485

RESUMO

Currently, coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been reported in almost all countries globally. No effective therapy has been documented for COVID-19, and the role of convalescent plasma therapy is unknown. In the current study, 6 patients with COVID-19 and respiratory failure received convalescent plasma a median of 21.5 days after viral shedding was first detected, all tested negative for SARS-CoV-2 RNA within 3 days after infusion, and 5 eventually died. In conclusion, convalescent plasma treatment can end SARS-CoV-2 shedding but cannot reduce the mortality rate in critically ill patients with end-stage COVID-19, and treatment should be initiated earlier.


Assuntos
Anticorpos Antivirais/uso terapêutico , Betacoronavirus/genética , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/terapia , Pneumonia Viral/mortalidade , Pneumonia Viral/terapia , Eliminação de Partículas Virais/imunologia , Adulto , Idoso , Doadores de Sangue , COVID-19 , China , Infecções por Coronavirus/virologia , Estado Terminal , Feminino , Humanos , Imunização Passiva/efeitos adversos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/virologia , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , SARS-CoV-2 , Taxa de Sobrevida , Resultado do Tratamento , Soroterapia para COVID-19
13.
Pharmacol Res ; 156: 104778, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32247822

RESUMO

Liraglutide is a new hypoglycemic drug. The previous studies have shown that liraglutide can improve the renal outcomes of patients with type 2 diabetes. Recently, it was approved by the U.S. FDA for used as a weight-loss drugs. However, the mechanism of its improvements of renal function in diabetic nephropathy patients is unclear. In addition, the effect of liraglutide on lipid metabolism is also not clear. The purpose of this study was to investigate the effects and mechanisms of liraglutide in alleviating ectopic lipid deposition (ELD) in rats with diabetic nephropathy (DN). Male Sprague-Dawley (SD) rats were treated with high-fat diet + unilateral nephrectomy + low-dose STZ combined to establish a DN rat model to evaluate the lipid-lowering effect of liraglutide. Liraglutide at 0.4 mg/kg/d were subcutaneous injected into for 12 weeks (DN + liraglutide group). After the DN rat model was established, body weight loss, 24-h urine volume increasing, serum triglycerides (TG) and serum total cholesterol (TCh) increasing, ectopic lipid droplet deposition in renal tubular increasing, mesangial proliferation in renal tissue were observed in DN rats. The treatment with liraglutide could reduce the body weight and the average daily food intake of the rats, as well as TG, TCh, and ectopic lipid droplet deposition in renal tubular. Metabolomics result showed that serum differential metabolites between the DN - vehicle control group and the DN + liraglutide group mainly included serine, threonine, phenylalanine, oxyproline, threonine, sorbitol, glyceryl monostearate, glycerol monostearate, and ß-d-glucuronic acid. Moreover, liraglutide can reduce plasma lipid levels in DN rats by increasing the products of lipolysis including 1-monopalmitin and 1-monoostearin. Immunohistochemistry and Western blot showed that the expression levels of lipid synthesis-related sterol regulatory element binding protein 1 (SREBP-1) and fatty acid synthase (FAS) were significantly increased, and lipolysis-related adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL) were significantly decreased both in the renal tissue of DN rats and PA-induced HK-2 cells (lipid droplet accumulation model). However, liraglutide can attenuate renal tubular ectopic lipid deposition in DN rats by inhibiting SREBP-1, FAS and increasing ATGL, HSL protein expression level, and also ameliorated PA-induced lipid accumulation in renal tubular epithelial cells. These lipid metabolism changes were attributed to liraglutide by upregulating AMP-activated protein kinase (AMPK) phosphorylation in the kidney of DN rats. Collectively, these findings confirm that liraglutide inhibits lipid synthesis and promotes lipolysis to attenuate renal ectopic lipid deposition in DN rats by promoting AMPK phosphorylation.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Nefropatias Diabéticas/tratamento farmacológico , Hipoglicemiantes/farmacologia , Hipolipemiantes/farmacologia , Túbulos Renais/efeitos dos fármacos , Gotículas Lipídicas/efeitos dos fármacos , Lipogênese/efeitos dos fármacos , Lipólise/efeitos dos fármacos , Liraglutida/farmacologia , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/metabolismo , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Dieta Hiperlipídica , Ativação Enzimática , Humanos , Túbulos Renais/metabolismo , Túbulos Renais/patologia , Gotículas Lipídicas/metabolismo , Gotículas Lipídicas/patologia , Lipídeos/sangue , Masculino , Fosforilação , Ratos Sprague-Dawley , Transdução de Sinais , Estreptozocina
14.
Acta Pharmacol Sin ; 41(3): 373-382, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31705123

RESUMO

Renal fibrosis is an inevitable outcome of all kinds of progressive chronic kidney disease (CKD). Recently, asiatic acid (AA), a triterpenoid compound from Chinese medicine Centella asiatica, has been found to attenuate renal fibrosis. In the current study, we explored the mechanisms underlying antifibrotic effect of AA on UUO model. SD rats and ICR mice were subjected to unilateral ureteral occlusion (UUO) surgery. Prior the surgery, rats were administered AA (10 mg·kg-1 per day, ig) for 7 days, whereas the mice received AA (15 mg·kg-1 per day, ig) for 3 days. UUO group displayed significant degree of renal dysfunction, interstitial fibrosis, oxidative stress, and activation of the TGF-ß/Smad and Wnt/ß-catenin signaling pathway in the kidney, these pathological changes were greatly ameliorated by pretreatment with AA. In addition, we found that co-treatment with GW9662, a selective PPAR-γ antagonist (1 mg·kg-1 per day, ip) for 7 days, abolished the protective effects of AA. We further revealed that AA pretreatment did not significantly change the expression levels of PPAR-γ in the kidney, but markedly increase the plasma levels of 15d-PGJ2, an endogenous ligand of PPAR-γ. In UUO mice, pretreatment with 15d-PGJ2 (24 µg·kg-1 per day, ip, for 7 days) produced similar protective effect as AA. Moreover, AA pretreatment upregulated the expression levels of active, nuclear-localized SREBP-1 (nSREBP-1), whereas fatostatin, a specific inhibitor of SREBP-1, decreased the expression of nSREBP-1, as well as the level of 15d-PGJ2. These results provide new insight into the antifibrotic mechanism of AA and endogenous metabolites might become a new clue for investigation of drug mechanism.


Assuntos
Fibrose/tratamento farmacológico , Nefropatias/tratamento farmacológico , PPAR gama/metabolismo , Triterpenos Pentacíclicos/farmacologia , Prostaglandina D2/análogos & derivados , Obstrução Ureteral/tratamento farmacológico , Administração Oral , Anilidas/farmacologia , Animais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Fibrose/metabolismo , Fibrose/patologia , Nefropatias/metabolismo , Nefropatias/patologia , Ligantes , Masculino , Camundongos , Camundongos Endogâmicos ICR , Estrutura Molecular , PPAR gama/antagonistas & inibidores , Triterpenos Pentacíclicos/administração & dosagem , Triterpenos Pentacíclicos/antagonistas & inibidores , Prostaglandina D2/administração & dosagem , Prostaglandina D2/biossíntese , Prostaglandina D2/sangue , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Obstrução Ureteral/metabolismo , Obstrução Ureteral/patologia
15.
Fish Shellfish Immunol ; 90: 30-39, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31004799

RESUMO

An 8 weeks feeding experiment was conducted to evaluate the effects of dietary supplementation with hydrolyzed yeast (HY) (Rhodotorula mucilaginosa) on growth performance, hematological parameters, immune response and antioxidant ability of juvenile Nile tilapia. Five isonitrogenous and isolipidic diets (32% protein and 4% lipid) with different levels (0%, 0.125%, 0.25%, 0.5%, 1%) of HY were formulated. Each diet was randomly assigned to quadruplicate groups of fish (initial body weight 19.1 ±â€¯0.01 g). Results indicated that significantly higher specific growth rate (SGR) and lower feed conversion rate (FCR) were obtained in fish fed 1% HY diet than that of fish fed 0% HY diet (P < 0.05). Fish fed 0.25% HY diet showed the lowest value of hepatopancreas somatic indices (HSI) and significantly lower than that of fish fed 0% HY diet (P < 0.05). Meanwhile, protein and ash in the whole-body content of fish fed 1% HY diet was significantly higher than that of fish fed 0%-0.5% HY diets. Serum immunological parameters showed that the lysozyme (LZM) activity and Complement C3 content were significantly increased by dietary supplementation of 0.5%-1% HY (P < 0.05). However, dietary supplementation with 0.125%-1% HY significantly decreased the activity of myeloperoxidase (MPO) (P < 0.05). Antioxidant status in serum and liver was significantly enhanced by dietary supplementation of 0.25%-1% HY through the remarkably improved superoxide dismutase (SOD) activity both in serum and liver, the raised total antioxidative capacity (T-AOC) of serum as well as the notably reduced malondialdehyde (MDA) content in the liver (P < 0.05). However, T-AOC in the liver was not significantly influenced among all diet treatments (P > 0.05). Villi height and intraepithelial lymphocytes (IEFs) of mid-intestine were significantly higher in fish fed 0.5%-1% HY diets (P < 0.05). The challenge test demonstrated the enhanced protection against Streptococcus iniae strain by the obtained higher cumulative survival rate. In conclusion, dietary supplementation of 1% HY could maintain the better growth performance, nutrient composition as well as immune response and antioxidant capacity for juvenile Nile tilapia.


Assuntos
Ciclídeos/imunologia , Resistência à Doença/imunologia , Doenças dos Peixes/imunologia , Rhodotorula/química , Infecções Estreptocócicas/veterinária , Ração Animal/análise , Animais , Antioxidantes/metabolismo , Ciclídeos/crescimento & desenvolvimento , Ciclídeos/fisiologia , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Distribuição Aleatória , Infecções Estreptocócicas/imunologia , Streptococcus iniae/fisiologia
16.
Hepatobiliary Pancreat Dis Int ; 18(3): 223-227, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31056483

RESUMO

BACKGROUND: Lower mean platelet volume (MPV) is an indicator of platelet activity in the setting of tumor development. This study was to assess the relationship between preoperative MPV and survival outcomes of patients with hepatocellular carcinoma (HCC) following liver transplantation (LT). METHODS: The demographic and clinical characteristics of 304 HCC patients following LT were retrieved from an LT database. All the patients were divided into the normal and lower MPV groups according to the median MPV. The factors were first analyzed using a Kaplan-Meier survival analysis, then the factors with P < 0.10 were selected for multivariate Cox regression analysis and were used to define the independent risk factors for poor prognosis. RESULTS: The 1-, 3-, and 5-year tumor free survival was 95.34%, 74.67% and 69.29% in the normal MPV group, respectively, and 95.40%, 59.97% and 42.94% in the lower MPV group, respectively (P < 0.01). No significant difference was observed in post-LT complications between the normal and lower MPV groups. Portal vein tumor thrombosis (PVTT) [hazard ratio (HR = 2.24; 95% confidence interval: 1.46-3.43; P < 0.01) and lower MPV (HR = 1.58; 95% confidence interval: 1.05-2.36; P = 0.03) were identified as independent prognostic risk factors for recipient survival. CONCLUSION: Preoperative lower MPV is a risk indicator of HCC patients survival outcomes after LT.


Assuntos
Plaquetas , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/efeitos adversos , Volume Plaquetário Médio , Recidiva Local de Neoplasia , Adulto , Idoso , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Bases de Dados Factuais , Feminino , Humanos , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
17.
Exp Cell Res ; 358(2): 335-342, 2017 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-28689811

RESUMO

BACKGROUND AND AIM: Acute liver failure (ALF) is an uncommon but serious disease still carrying a high mortality. This study aimed to investigate the mechanism of AMPK on D-GalN/LPS-induced ALF. METHODS: In this study, we utilized intraperitoneal injection of D-GalN/LPS to induce ALF model, and analyzed the expression of AMPK, inflammatory cytokines (TNF-α, IL-1ß and IL-6), Foxo3A and autophagy-related genes (Atg-5, Beclin-1, Atg-7) by real-time quantitative polymerase chain reaction (RT-PCR) in liver tissue. We also examined the level of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in serum of ALF mice. AMPK activation and inhibition of autophagy were induced by AICAR and 3-MA, respectively. Silence and overexpression of Foxo3A were performed by si-Foxo3A and pcDNA-Foxo3A, respectively. Lastly, the BMDM-conditioned medium (BMDM-CM) derived from BMDMs treated with AICAR and LPS were used to explore the effect of AMPK and Foxo3A on hepatocytes. RESULT: The expression of AMPK was decreased in liver tissue and the level of ALT and AST were increased in serum of D-GalN/LPS-induced ALF mice. AMPK activation ameliorated ALF by inhibiting inflammation (downregulated TNF-α, IL-1ß and IL-6 expression), activating autophagy (increased Atg-5, Beclin-1 and Atg-7 expression) and upregulating Foxo3A expression. Silence of Foxo3A decreased AMPK-activated autophagy, but overexpressing Foxo3A attenuated liver failure by activating autophagy. In addition, AMPK activation alleviated liver failure in vitro. CONCLUSION: Thus, AMPK/Foxo3A/autophagy pathway may be an effective treatment approach to ameliorate ALF.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia/efeitos dos fármacos , Proteína Forkhead Box O3/metabolismo , Galactosamina/farmacologia , Lipopolissacarídeos/farmacologia , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Hepatócitos/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Fator de Necrose Tumoral alfa/farmacologia
18.
J Proteome Res ; 15(10): 3802-3812, 2016 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-27636000

RESUMO

Chronic kidney disease (CKD) has emerged as a major public health problem worldwide. It frequently progresses to end-stage renal disease, which is related to very high cost and mortality. Novel biomarkers can provide insight into the novel mechanism, facilitate early detection, and monitor progression of CKD and its response to therapeutic interventions. To identify potential biomarkers, we applied an UPLC-HDMS together with univariate and multivariate statistical analyses using plasma samples from patients with CKD of diverse etiologies (100 sera in discovery set and 120 sera in validation set) and two different rat models of CKD. Using comprehensive screening and validation workflow, we identified a panel of seven metabolites that were shared by all patients and animals regardless of the underlying cause of CKD. These included ricinoleic acid, stearic acid, cytosine, LPA(16:0), LPA(18:2), 3-methylhistidine, and argininic acid. The combination of these seven biomarkers enabled the discrimination of patients with CKD from healthy subjects with a sensitivity of 83.3% and a specificity of 96.7%. In addition, these biomarkers accurately reflected improvements in renal function in response to the therapeutic interventions. Our results indicated that the identified biomarkers may improve the diagnosis of CKD and provide a novel tool for monitoring of the progression of disease and response to treatment in CKD patients.


Assuntos
Biomarcadores/análise , Metabolômica/métodos , Insuficiência Renal Crônica/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Estudos de Casos e Controles , Progressão da Doença , Diagnóstico Precoce , Feminino , Humanos , Rim/fisiologia , Masculino , Pessoa de Meia-Idade , Ratos , Recuperação de Função Fisiológica , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/metabolismo , Sensibilidade e Especificidade , Resultado do Tratamento
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(4): 1033-6, 2015 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-26197597

RESUMO

During the combustion of coal or biomass, the inherent alkali metals in the fuel will be released to the gas phase. The released alkali species condensed during the cooling of the flue gas, which may subsequently cause problems with ash deposition and corrosion in thermal fuel conversion systems. Laser Induced Breakdown Spectroscopy (LIBS) is an effective technique to measure the alkali species in the plume of burning coal or biomass. In this study, an LIBS experimental system with a flat flame burner was set up, and the Flame Emission Spectroscopy (FES) and LIBS of K in the flat flame environment were measured using different ICCD gate-width times. The experimental results revealed that with the same ICCD gate-width time, the LIBS intensity of K was higher than the FES intensity of K in the flat flame. With the increase of the ICCD gate-width time, both intensities increased, but their increase rates were different: the increase rate of the LIBS intensity of K was firstly fast then became slow, but the increase rate of the FES intensity of K was constant. Furthermore, the intensity ratio of LIBS to FES of K increased monotonically with the ICCD gate-width time in the range of 0-8 µs, until reaching approximately 4. Then, further increasing the ICCD gate-width time, such ratio decreased slowly with an asymptote value of 1. After analyzing the influences of the FES on the LIBS measurement of K in a flame condition, it is proposed that to minimize such influence, the optimization of the ICCD gate-width time was necessary, which maximized the intensity ratio of LIBS to FES-of K and facilitated the measurement accuracy of K in the flame environment using LIBS.

20.
Zhong Yao Cai ; 37(9): 1636-40, 2014 Sep.
Artigo em Zh | MEDLINE | ID: mdl-25857167

RESUMO

OBJECTIVE: To establish an HPLC method for determination of four flavonoids in rat plasma after oral Ecliptae Herba extract. METHODS: HPLC separation was carried out in a Neocleodur 100-5 C18 column (250 mm x 4.6 mm, 5 microm) with mobile phase A (consisting of methanol-0.2% phosphoric acid = 50:50) and mobile phase B (acetonitrile)with gradient elution at the flow rate of 1.0 mL/min. The detection wavelength was 350 nm and the column temperature was maintained at 40 degrees C. RESULTS: There were good linear relationships between concentration and peak area ratio of luteolin, apigenin, scutellarein and diosmetin in the ranges of 0.02-50 microg/mL with the recovery rates of 71.5%-90.2%. CONCLUSION: This method is rapid, accurate and reproducible for determination of luteolin, apigenin, scutellarein and diosmetin in rat plasma and study on pharmacokinetics of Ecliptae Herba extract.


Assuntos
Eclipta , Animais , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas , Flavonoides , Extratos Vegetais , Ratos
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