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1.
Chem Commun (Camb) ; 59(93): 13903-13906, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37936495

RESUMO

A carbonate intercalated magnesium aluminum layered double hydroxide is used as an anode material for lithium-ion batteries, displaying a maximum discharge specific capacity of 814 mA h g-1 at 200 mA g-1 in this work through utilizing the valence variation of Mg and the conversion between LiOH and LiH/Li2O.

2.
ACS Appl Mater Interfaces ; 15(32): 38540-38549, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37550280

RESUMO

Aqueous chloride-ion batteries (ACIBs) with environmental friendliness and high safety hold great potential to fulfill the green energy demand for ocean desalination. Herein, for the first time, a composite consisting of Cl--intercalated CoFe layered double hydroxides (CoFe-Cl-LDH) cross-linked with CNTs (CoFe-Cl-LDH/CNT) is synthesized and demonstrated to be a novel high-performance anode for ACIBs in a neutral NaCl aqueous solution. While exhibiting a high initial capacity of ∼190 mAh g-1 at 200 mA g-1, CoFe-Cl-LDH/CNT is capable of delivering a reversible capacity of ∼125 mAh g-1 after 200 cycles. At a high current density of 400 mA g-1, it still holds a capacity of ∼120 mAh g-1. The excellent Cl- storage performance can be contributed to the unique topochemical transformation feature that reverses intercalation/deintercalation of Cl- along with valence changes of Co2+/Co3+ and Fe2+/Fe3+ during charge/discharge and the improved electronic conductivity by hybridizing with CNTs. It is interesting that the invertible insertion/extraction of interlayer H2O was discovered, which could be beneficial to the capacity after cycles to a certain extent. The Cl--intercalated LDH material declared in this work shows its feasibility on Cl- capture/release in aqueous anion-type batteries and provides a new opportunity for future development of ACIBs or aqueous desalination technology.

3.
Biotechnol Bioeng ; 120(4): 1133-1146, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36585353

RESUMO

Engineering biological systems to test new pathway variants containing different enzyme homologs is laborious and time-consuming. To tackle this challenge, a strategy was developed for rapidly prototyping enzyme homologs by combining cell-free protein synthesis (CFPS) with split green fluorescent protein (GFP). This strategy featured two main advantages: (1) dozens of enzyme homologs were parallelly produced by CFPS within hours, and (2) the expression level and activity of each homolog was determined simultaneously by using the split GFP assay. As a model, this strategy was applied to optimize a 3-step pathway for nicotinamide mononucleotide (NMN) synthesis. Ten enzyme homologs from different organisms were selected for each step. Here, the most productive homolog of each step was identified within 24 h rather than weeks or months. Finally, the titer of NMN was increased to 1213 mg/L by improving physiochemical conditions, tuning enzyme ratios and cofactor concentrations, and decreasing the feedback inhibition, which was a more than 12-fold improvement over the initial setup. This strategy would provide a promising way to accelerate design-build-test cycles for metabolic engineering to improve the production of desired products.


Assuntos
Enzimas , Engenharia Metabólica , Mononucleotídeo de Nicotinamida , Engenharia Metabólica/métodos , Mononucleotídeo de Nicotinamida/biossíntese , Enzimas/química , Enzimas/genética , Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/genética , Vias Biossintéticas
4.
ACS Appl Mater Interfaces ; 14(49): 54812-54821, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36458834

RESUMO

Transition-metal compounds (oxides, sulfides, hydroxides, etc.) as lithium-ion battery (LIB) anodes usually show extraordinary capacity larger than the theoretical value due to the transformation of LiOH into Li2O/LiH. However, there has rarely been a report relaying the transformation of LiOH into Li2O/LiH as the main reaction for LIBs, due to the strong alkalinity of LiOH leading to battery deterioration. In this work, layered silicate MgAl saponite (MA-SAP) is applied as a -OH donor to generate LiOH as the anode material of LIBs for the first time. The MA-SAP maintains a layered structure during the (dis)charging process and has zero-strain characteristic on the (001) crystal plane. In the discharging process, Mg, Al, and Si in the saponite sheets become electron-rich, while the active hydroxyl groups escape from the sheets and combine with lithium ions to form LiOH in the "caves" on sheets, and the LiOH continues to decompose into Li2O and LiH. Consequently, the MA-SAP delivers a maximum capacity of 536 mA h·g-1 at 200 mA·g-1 with a good high-current discharging ability of 155 mA h·g-1 after 1000 cycles under 1 A·g-1. Considering its extremely low cost and completely nontoxic characteristics, MA-SAP has great application prospects in energy storage. In addition, this work has an enlightening effect on the development of new anodes based on extraordinary mechanisms.

5.
ACS Appl Mater Interfaces ; 14(21): 24518-24525, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35603940

RESUMO

A fluoride-ion battery (FIB) is a novel type of energy storage system that has a higher volumetric energy density and low cost. However, the high working temperature (>150 °C) and unsatisfactory cycling performance of cathode materials are not favorable for their practical application. Herein, fluoride ion-intercalated CoFe layered double hydroxide (LDH) (CoFe-F LDH) was prepared by a facile co-precipitation approach combined with ion-exchange. The CoFe-F LDH shows a reversible capacity of ∼50 mAh g-1 after 100 cycles at room temperature. Although there is still a big gap between FIBs and lithium-ion batteries, the CoFe-F LDH is superior to most cathode materials for FIBs. Another important advantage of CoFe-F LDH FIBs is that they can work at room temperature, which has been rarely achieved in previous reports. The superior performance stems from the unique topochemical transformation property and small volume change (∼0.82%) of LDH in electrochemical cycles. Such a tiny volume change makes LDH a zero-strain cathode material for FIBs. The 2D diffusion pathways and weak interaction between fluoride ions and host layers facilitate the de/intercalation of fluoride ions, accompanied by the chemical state changes of Co2+/Co3+ and Fe2+/Fe3+ couples. First-principles calculations also reveal a low F- diffusion barrier during the cyclic process. These findings expand the application field of LDH materials and propose a novel avenue for the designs of cathode materials toward room-temperature FIBs.

6.
Bioorg Med Chem Lett ; 64: 128654, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35259487

RESUMO

In this study, a novel batch of indazole containing 1,2,3-triazole agents were designed and synthesized. The antiproliferative activity of target compounds in four human cancer cells, PC-3 (human prostate cancer cell), MCF-7 (human breast cancer cell), HepG-2 (human hepatoma cell) and MGC-803 (human gastric cancer cell), was evaluated by thiazole blue (MTT). In the antiproliferative activity screening, we were surprised to find that most compounds have specific cytotoxicity to PC-3 cancer cells. In particular, 9a has an IC50 value of 4.42 ± 0.06 µmol/L against PC-3 cell. Cloning experiments showed that 9a could inhibit the formation of PC-3 cancer cell clone in a dose-dependent manner. Through cell cycle arrest experiment, we found that compound 9a can block the cell cycle in G2/M phase and inhibit cell proliferation. Finally, by evaluating the safety of compound 9a, we noticed that it showed fairly good safety both in vivo and in vitro. Overall, based on the biological activity evaluation and safety, analogue 9a can be viewed as a potential lead compound for further development of novel anti-prostate cancer drug.


Assuntos
Antineoplásicos , Neoplasias da Próstata , Antineoplásicos/farmacologia , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Indazóis/farmacologia , Masculino , Estrutura Molecular , Neoplasias da Próstata/tratamento farmacológico , Esqueleto , Relação Estrutura-Atividade , Triazóis/farmacologia
7.
J Ethnopharmacol ; 287: 114940, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-34968665

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Sanren decoction (SRD) is a well-known traditional Chinese medicine prescription containing eight kinds of materials. SRD has been used mainly in China for more than 200 years for the treatment of respiratory disorders that co-occur with a bad fever after midday. AIM OF THE STUDY: To evaluate the acute and 28-day subacute toxicity of an aqueous extract of SRD using in vivo methods. MATERIALS AND METHODS: To determine acute toxicity, SRD was administered by gavage at a dosage of 58.5 g/kg/day to male and female mice for 7 days. To determine subacute toxicity, SRD was administered at 3.3, 6.5, or 13 g/kg/day to male and female rats for 28 days. The general behavior, body weight, biochemical and hematological parameters, organ coefficients and pathological morphology of the treated animals were analyzed. RESULTS: Neither acute nor subacute concentrations of SRD caused significant changes in the body weights, general behavior, hematology and biochemical parameters, organ weights, or histopathological appearances of the liver, kidney, spleen, brain, lung or heart in mice or rats. CONCLUSIONS: The administration of SRD can be considered safe within the conditions of this study.


Assuntos
Peso Corporal/efeitos dos fármacos , Medicamentos de Ervas Chinesas/toxicidade , Tamanho do Órgão/efeitos dos fármacos , Animais , Animais não Endogâmicos , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/administração & dosagem , Feminino , Masculino , Camundongos , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade Aguda , Testes de Toxicidade Subaguda
8.
Sheng Wu Gong Cheng Xue Bao ; 37(3): 939-949, 2021 Mar 25.
Artigo em Chinês | MEDLINE | ID: mdl-33783159

RESUMO

Pichia pastoris is one of the most widely used recombinant protein expression systems. In this study, a novel method for rapid screening of P. pastoris strains capable of efficiently expressing recombinant proteins was developed. Firstly, the ability to express recombinant proteins of the modified strain GS115-E in which a functional Sec63-EGFP (Enhanced green fluorescent protein) fusion protein replaced the endogenous endoplasmic reticulum transmembrane protein Sec63 was tested. Next, the plasmids carrying different copy numbers of phytase (phy) gene or xylanase (xyn) gene were transformed into GS115-E to obtain recombinant strains with different expression levels of phytase or xylanase, and the expression levels of EGFP and recombinant proteins in different strains were tested. Finally, a flow cytometer sorter was used to separate a mixture of cells with different phytase expression levels into sub-populations according to green fluorescence intensity. A good linear correlation was found between the fluorescence intensities of EGFP and the expression levels of the recombinant proteins in the recombinant strains (0.8<|R|<1). By using the flow cytometer, high-yielding P. pastoris cells were efficiently screened from a mixture of cells. The expression level of phytase of the selected high-fluorescence strains was 4.09 times higher than that of the low-fluorescence strains after 120 h of methanol induction. By detecting the EGFP fluorescence intensity instead of detecting the expression level and activity of the recombinant proteins in the recombinant strains, the method developed by the present study possesses the greatly improved performance of convenience and versatility in screening high-yielding P. pastoris strains. Combining the method with high-throughput screening instruments and technologies, such as flow cytometer and droplet microfluidics, the speed and throughput of this method will be further increased. This method will provide a simple and rapid approach for screening and obtaining P. pastoris with high abilities to express recombinant proteins.


Assuntos
6-Fitase , Pichia , 6-Fitase/genética , Pichia/genética , Plasmídeos , Proteínas Recombinantes/genética , Saccharomycetales
9.
Sensors (Basel) ; 19(23)2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31801282

RESUMO

Surface temperature variation in a broiler's head can be used as an indicator of its health status. Surface temperatures in the existing thermograph based animal health assessment studies were mostly obtained manually. 2185 thermal images, each of which had an individual broiler, were captured from 20 broilers. Where 15 broilers served as the experimental group, they were injected with 0.1mL of pasteurella inoculum. The rest, 5 broilers, served as the control group. An algorithm was developed to extract head surface temperature automatically from the top-view broiler thermal image. Adaptive K-means clustering and ellipse fitting were applied to locate the broiler's head region. The maximum temperature inside the head region was extracted as the head surface temperature. The developed algorithm was tested in Matlab® (R2016a) and the testing results indicated that the head region in 92.77% of the broiler thermal images could be located correctly. The maximum error of the extracted head surface temperatures was not greater than 0.1 °C. Different trend features were observed in the smoothed head surface temperature time series of the broilers in experimental and control groups. Head surface temperature extracted by the presented algorithm lays a foundation for the development of an automatic system for febrile broiler identification.

10.
Cytotechnology ; 71(5): 1033-1041, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31535308

RESUMO

ßKlotho as the major role is a necessary auxiliary protein when fibroblast growth factor 21 (FGF21) binds FGF21 receptors (FGFR) for activating intracellular signaling pathways that ultimately generate biological effects. To achieve the aim of high throughput screening of FGF21 analogues, we established 3T3-L1-ßKlotho cells that could stably express ßklotho protein. The glucose uptake, expression of GLUT1 mRNA and activation of FGF signaling molecules ERK1/2 phosphorylation were detected by GOD-POD assay, real-time PCR analysis and western blotting assay in 3T3-L1-ßKlotho cells and 3T3-L1 adipocytes, respectively. The results showed that FGF21 increased glucose uptake significantly in a dose-dependent and time-dependent manner in 3T3-L1-ßKlotho cells. 3T3-L1-ßKlotho cells stimulated with FGF21 up-regulated the transcriptional levels of GLUT1 mRNA obviously. FGF21 activated the FGF signaling molecules ERK1/2 in 3T3-L1-ßKlotho cells. In addition, the same results were obtained in 3T3-L1 adipocytes. Furthermore, FGF21-stimulated elevation of glucose uptake, GLUT1 mRNA transcription and the phosphorylation of ERK1/2 were dramatically attenuated by pretreatment of cells with FGFR specific inhibitor SU5402 in 3T3-L1-ßKlotho cells. This study demonstrated that the cell model could be applied to high throughput screen FGF21 analogues.

11.
Sci Rep ; 7(1): 11113, 2017 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-28894268

RESUMO

Pichia pastoris is a widely used heterologous protein production workhorse. However, with its multiple genetic modifications to solve bottlenecks for heterologous protein productivity, P. pastoris lacks selectable markers. Existing selectable marker recycling plasmids have drawbacks (e.g., slow growth and conditional lethality). Here, zeocin-resistance marker recycling vectors were constructed using the Cre/loxP recombination system. The vectors were used to (i) knock in heterologous phytase, xylanase and lipase expression cassettes, (ii) increase the phytase, xylanase and lipase gene copy number to 13, 5, and 5, respectively, with vector introduction and (iii) engineer the secretion pathway by co-overexpressing secretion helper factors (Sly1p and Sec1p) without introducing selectable markers, giving a phytase field of 0.833 g/L. The vectors allow selectable marker recycling and would be a useful tool to engineer P. pastoris for high heterologous protein productivity.


Assuntos
Marcadores Genéticos , Pichia/genética , Plasmídeos/genética , 6-Fitase/genética , 6-Fitase/metabolismo , Dosagem de Genes , Expressão Gênica , Ordem dos Genes , Vetores Genéticos , Lipase/genética , Lipase/metabolismo , Pichia/metabolismo , Recombinação Genética , Xilosidases/genética , Xilosidases/metabolismo
12.
Exp Ther Med ; 12(5): 3417-3424, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27882173

RESUMO

Human fibroblast growth factor 21 (hFGF-21) is involved in numerous metabolic processes and elevated hFGF-21 levels are associated with many metabolic diseases. However, the role hFGF-21 serves in the metabolic system is not fully understood. A humanized anti-hFGF-21 monoclonal antibody (mAb) would provide a novel method for further investigations into the role hFGF-21 serves in the metabolic system and related diseases, which may reveal therapeutic targets for future treatment of these diseases. The present study aimed to prepare an anti-hFGF-21 mAb, followed by identification of its characteristics and bioactivity in vitro. The results of the present study identified that the anti-hFGF-21 mAb (clone 2D8) produced had good specificity, had an immunoglobulin isotype of IgG2b and a titer of 1:1.024×106. hFGF-21 was screened for epitopes using fluorescence-activated cell sorting, which revealed a specific 15 amino acid sequence (YQSEAHGLPLHLPGN) that the anti-hFGF-21 mAb recognized. In vitro bioactivity of anti-hFGF-21 was determined using a glucose uptake assay and by measuring the expression of glucose transporter 1 (GLUT1) messenger RNA (mRNA) in 3T3-L1 adipocytes. This revealed that hFGF-21-dependent glucose uptake and GLUT1 mRNA expression were negatively correlated with increasing levels of the anti-hFGF-21 mAb tested, and that hFGF-21 activity could be overcome by increasing concentrations of the mAb, demonstrating that the mAb has hFGF-21-neutralizing activity in vitro.

13.
Artigo em Inglês | MEDLINE | ID: mdl-27765883

RESUMO

INTRODUCTION: Activation of T lymphocytes, for which potassium channels are essential, is involved in the development of hypertension. In this study, we explored the inhibitory effects of telmisartan on the culture and proliferation of and Kv1.3 potassium channel expression in peripheral blood CD4+ T lymphocytes derived from Xinjiang Kazakh patients with hypertension. METHODS: CD4+ T-cell samples from hypertensive Kazakh patients and healthy Kazakh people were divided into healthy control, case control, telmisartan, and 4-aminopytidine groups. Changes in the expression levels of interleukin (IL)-6 and IL-17 in the blood of the healthy control and case control subjects were detected by enzyme-linked immunosorbent assay. Peripheral blood CD4+ T lymphocytes were first activated and proliferated in vitro and then incubated for 0, 24, and 48 h under various treatment conditions. Thereafter, changes in CD4+ T-lymphocytic proliferation were determined using Cell Counting Kit-8 and microscope photography. Changes in messenger RNA (mRNA) and protein expression of the Kv1.3 potassium channel in CD4+ T lymphocytes were detected using real-time quantitative polymerase chain reaction and Western blots, respectively. RESULTS: The IL-6 and IL-17 expression levels were significantly higher in the blood of the hypertensive Kazakh patients than in the healthy Kazakh people. Telmisartan inhibited T-lymphocytic proliferation, as well as the mRNA and protein expression of the Kv1.3 potassium channel in CD4+ T lymphocytes, and the inhibitory effects were time-dependent, with the strongest inhibition observed after 48 h and significantly weaker inhibition observed after 24 h of treatment. CONCLUSIONS: Telmisartan may potentially regulate hypertensive inflammatory responses by inhibiting T-lymphocytic proliferation and Kv1.3 potassium channel expression in CD4+ T lymphocytes.


Assuntos
Benzimidazóis/farmacologia , Benzoatos/farmacologia , Linfócitos T CD4-Positivos/patologia , Etnicidade , Hipertensão/imunologia , Hipertensão/patologia , Canal de Potássio Kv1.3/metabolismo , Western Blotting , Linfócitos T CD4-Positivos/efeitos dos fármacos , Estudos de Casos e Controles , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Células Cultivadas , China , Demografia , Feminino , Humanos , Hipertensão/sangue , Interleucina-17/sangue , Interleucina-6/sangue , Canal de Potássio Kv1.3/genética , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Telmisartan
14.
Kardiol Pol ; 74(5): 476-488, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26502942

RESUMO

BACKGROUND AND AIM: Increasing evidence indicates that chronic inflammation is a direct or indirect manifestation of hypertension. Potassium channels are thought to be critical for lymphocyte activation, which suggests that hypertension may be an inflammatory disease initiated at the ion channel level. METHODS: This study investigated changes in interleukin (IL)-6, IL-17, and transforming growth factor beta (TGF-b1) expression in the blood of Kazakh hypertensive patients in Northwest China using ELISA technology. Whole-cell patch clamp technology was used to evaluate current changes associated with Kv1.3 and KCa3.1 in peripheral blood T lymphocytes of hypertensive patients, and to investigate current changes induced by telmisartan. We also investigated the effects of telmisartan on expression of Kv1.3 and KCa3.1 at mRNA and protein levels in peripheral blood T lymphocytes using real-time polymerase chain reaction and Western blot analysis. RESULTS: Expression of IL-6, IL-17 and TGF-b1 in the blood of Kazakh hypertensive patients in Northwest China was significantly higher than in healthy controls (p < 0.05). The current mediated by Kv1.3 and KCa3.1 and the corresponding expression at mRNA and protein levels in T lymphocytes were also higher in these hypertensive patients than in controls (p < 0.05). Telmisartan intervention for 24 h and 48 h inhibited the current and expression of Kv1.3 and KCa3.1 at mRNA and protein levels (p < 0.05). CONCLUSIONS: These results indicated that the increase in functional Kv1.3 and KCa3.1 channels expressed in T lymphocytes of Kazakh patients with hypertension was blocked by telmisartan, resulting in a reduced inflammatory response. These results provide theoretical support for the treatment of hypertension at the cellular ion channel level.


Assuntos
Benzimidazóis/farmacologia , Benzoatos/farmacologia , Hipertensão/metabolismo , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/antagonistas & inibidores , Canal de Potássio Kv1.3/antagonistas & inibidores , Linfócitos T/metabolismo , Anti-Hipertensivos/farmacologia , China , Citocinas/sangue , Feminino , Expressão Gênica , Humanos , Hipertensão/sangue , Hipertensão/tratamento farmacológico , Hipertensão/etnologia , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/genética , Cazaquistão/etnologia , Canal de Potássio Kv1.3/genética , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Bloqueadores dos Canais de Potássio/farmacologia , Linfócitos T/efeitos dos fármacos , Telmisartan
15.
Toxicol Appl Pharmacol ; 290: 43-53, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26592322

RESUMO

Fibroblast growth factor 21 (FGF-21) is a secreted protein, which has anti-diabetic and lipocaic effects, but its ability to protect against hepatic fibrosis has not been studied. In this study, we investigated the ability of FGF-21 to attenuate dimethylnitrosamine (DMN)-induced hepatic fibrogenesis in mice and the mechanism of its action. Hepatic fibrosis was induced by injection of DMN, FGF-21 was administered to the mice once daily in association with DMN injection till the end of the experiment. Histopathological examination, tissue 4-hydroxyproline content and expressions of smooth muscle α-actin (α-SMA) and collagen I were measured to assess hepatic fibrosis. Ethanol/PDGF-BB-activated hepatic stellate cells (HSCs) were used to understand the mechanisms of FGF-21 inhibited hepatic fibrogenesis. Results showed that FGF-21 treatment attenuated hepatic fibrogenesis and was associated with a significant decrease in intrahepatic fibrogenesis, 4-hydroxyproline accumulation, α-SMA expression and collagen I deposition. FGF-21 treatment inhibited the activation of HSCs via down-regulating the expression of TGF-ß, NF-κB nuclear translocation, phosphorylation levels of smad2/3 and IκBα. Besides, FGF-21 treatment caused activated HSC apoptosis with increasing expression of Caspase-3, and decreased the ratio of Bcl-2 to Bax. In conclusion, FGF-21 attenuates hepatic fibrogenesis and inhibits the activation of HSC warranting the use of FGF-21 as a potential therapeutic agent in the treatment of hepatic fibrosis.


Assuntos
Fatores de Crescimento de Fibroblastos/farmacologia , Cirrose Hepática/tratamento farmacológico , Transdução de Sinais , Proteína Smad2/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Actinas/genética , Actinas/metabolismo , Animais , Apoptose/efeitos dos fármacos , Caspase 3/genética , Caspase 3/metabolismo , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Dimetilnitrosamina/toxicidade , Regulação para Baixo , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Hidroxiprolina/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Cirrose Hepática/patologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , NF-kappa B/genética , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Smad2/genética , Proteína Smad3/genética , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta/genética , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
16.
Endocrine ; 52(3): 527-40, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26607153

RESUMO

Previous studies reveal that fibroblast growth factor 21 (FGF21) sensitizes insulin to achieve a synergy in regulating glucose metabolism. Here, we report that insulin sensitizes FGF21 in regulating both glucose and lipid metabolisms. db/db diabetic mice were subcutaneously administrated once a day for 6 weeks. Effective dose of insulin (1 U) could control blood glucose level of the db/db mice for maximum of 2 h, increased the body weight of the db/db mice and did not improve serum lipid parameters. In contrast, effective dose of FGF21 (0.5 mg/kg) could maintain blood glucose of the db/db mice at normal level for at least 24 h, repressed the weight gain of the mice and significantly improved lipid parameters. Ineffective doses of FGF21 (0.125 mg/kg) and insulin had no effect on blood glucose level of the db/db mice after 24 h administration, body weight or lipid parameters. However, combination of the two ineffective doses could maintain blood glucose level of the db/db mice for at least 24 h, suppressed weight gain and significantly improved lipid parameters. These results suggest that insulin sensitizes FGF21 in regulating both glucose and lipid metabolism. The results aimed to study the molecular basis of FGF21 sensitization indicates that combination of the two ineffective doses increased the mRNA expression of glut1, glut4, ß-Klotho, sirt1, pgc-1α, ucp-1 and AKT phosphorylation, decreased fasn. The results demonstrate that insulin sensitizes FGF21 through elevating the phosphorylation of common gene Akt and amplifying FGF21 downstream signaling, including increasing expression of glut1 sirt1, pgc-1α, ucp-1, and decreasing fasn expression. In summary, we reports herein for the first time that insulin sensitizes FGF21 to achieve a synergy in regulating glucose and lipid metabolism. Along with previous studies, we conclude that the synergistic effect between FGF21 and insulin is realized through mutual sensitization.


Assuntos
Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/metabolismo , Fatores de Crescimento de Fibroblastos/farmacologia , Insulina/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/patologia , Sinergismo Farmacológico , Glucose/metabolismo , Resistência à Insulina , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína Oncogênica v-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos
17.
Curr Pharm Biotechnol ; 16(10): 902-10, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26144596

RESUMO

For a long time, researchers have attempted to replace human plasmaderived immunoglobulin against HBV with recombinant HBV antibodies for therapeutic purposes, but failed to develop the products. One of the reasons may be lack of high throughput antibody screening tool. In this study, we screened an antibody library from immunized subjects by a powerful bacterial display technology. The capacity of the ScFv library was 10(9), 117 individual clones against HBV pre- S1 were initially selected and sequenced, the homology of these clones ranged from 59.7% -68.7%. Ten clones were randomly selected based on florescence intensity by FACS. The ScFv antibodies were expressed in E.coli and purified to examine their neutralization ability. First, we tested the ability of these clones to block the binding of the pre-S1 polypeptide to the HBV sensitive cells Chang liver cells and HepG2 cells, then, we examined the ability of these clones to inhibit the infection of the Change liver cells by HBV released from HepG2.2.15 cells by detection of viral DNA and hepatitis B virus e antigen (HBeAg) in the supernatant of Chang liver cells. Results showed that 4 (clone 3, 7, 9 and 31) out of the ten clones could significantly reduce the binding of pre-S1 polypeptide to Chang liver cells in a dose-dependent manner. Treatment with the same clones (clone 3, 7, 9 and 31) could dramatically reduce the contents of HBV DNA in the media of the infected Chang liver cells by 29.4, 7.89, 58.8, 76.9, respectively, and the amount of HBeAg by 60.2%, 32.6%, 66.1% and 68.1%, respectively. These results suggest that these clones can neutralize HBV infection and have the potential to become therapeutic antibodies against HBV infection to replace the human plasma-derived immunoglobulin.


Assuntos
Hepatite B/imunologia , Anticorpos de Cadeia Única/isolamento & purificação , Vacinação , Células Hep G2 , Antígenos de Superfície da Hepatite B , Humanos , Masculino , Proteínas Recombinantes/imunologia
18.
Dig Dis Sci ; 60(10): 3032-43, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26003555

RESUMO

PURPOSE: In this study, we explored whether treatment with FGF-21 could prevent diethylnitrosamine (DEN) induced hepatocarcinogenesis in mice. METHODS & RESULTS: Hepatoma was induced by injection of DEN every three days for 18 weeks. For the prophylactic experiment, mice were firstly injected with FGF-21 for 2 weeks, then FGF-21 was administered to the mice once daily in association with DEN injection till the end of the experiment. The hepatoma incidence of mice treated with FGF-21 was 13.3%, while the incidence of mice treated with saline was 61.5%. To understand the mechanisms, we compared the expression of ßklotho (KLB) and oxidative stress level in the livers between the mice treated with FGF-21 and saline. We found that FGF-21 could suppress DEN-induced oxidative stress and up-regulate the expression of KLB in the livers. To confirm these results, we compared the expression of KLB in L02 cells stimulated with or without FGF-21. Besides, we established DEN-induced oxidative stress cell model to affirm the relationship between FGF-21 and DEN-induced oxidative stress in vitro. Results showed that FGF-21 increased the expression of KLB and diminished the DEN-induced oxidative stress in vitro in a dose dependent manner. CONCLUSION: Systemic administration of FGF-21 can prevent DEN-induced hepatocarcinogenesis via suppressing oxidative stress and increasing the expression of KLB.


Assuntos
Carcinogênese/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Fatores de Crescimento de Fibroblastos/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Animais , Western Blotting , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dietilnitrosamina/farmacologia , Modelos Animais de Doenças , Esquema de Medicação , Imuno-Histoquímica , Proteínas Klotho , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/patologia , Proteínas de Membrana/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Camundongos , Neoplasias Experimentais/prevenção & controle , Distribuição Aleatória , Reação em Cadeia da Polimerase em Tempo Real/métodos , Valores de Referência , Sensibilidade e Especificidade
19.
Pharmacol Biochem Behav ; 133: 122-31, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25871519

RESUMO

Fibroblast growth factor 21 (FGF21) is a hormone secreted predominantly in the liver, pancreas and adipose tissue. Recently, it has been reported that FGF21-Transgenic mice can extend their lifespan compared with wild type counterparts. Thus, we hypothesize that FGF21 may play some roles in aging of organisms. In this study d-galactose (d-gal)-induced aging mice were used to study the mechanism that FGF21 protects mice from aging. The three-month-old Kunming mice were subcutaneously injected with d-gal (180mg·kg(-1)·d(-1)) for 8weeks and administered simultaneously with FGF21 (1, 2 or 5mg·kg(-1)·d(-1)). Our results showed that administration of FGF21 significantly improved behavioral performance of d-gal-treated mice in water maze task and step-down test, reduced brain cell damage in the hippocampus, and attenuated the d-gal-induced production of MDA, ROS and advanced glycation end products (AGEs). At the same time, FGF21 also markedly renewed the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and total anti-oxidation capability (T-AOC), and decreased the enhanced total cholinesterase (TChE) activity in the brain of d-gal-treated mice. The expression of aldose reductase (AR), sorbitol dehydrogenase (SDH) and member-anchored receptor for AGEs (RAGE) declined significantly after FGF21 treatment. Furthermore, FGF21 suppressed inflamm-aging by inhibiting IκBα degradation and NF-κB p65 nuclear translocation. The expression levels of pro-inflammatory cytokines, such as TNF-α and IL-6, decreased significantly. In conclusion, these results suggest that FGF21 protects the aging mice brain from d-gal-induced injury by attenuating oxidative stress damage and decreasing AGE formation.


Assuntos
Envelhecimento/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Transtornos Cognitivos/tratamento farmacológico , Fatores de Crescimento de Fibroblastos/farmacologia , Galactose/farmacologia , Produtos Finais de Glicação Avançada/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Encéfalo/metabolismo , Transtornos Cognitivos/induzido quimicamente , Fatores de Crescimento de Fibroblastos/uso terapêutico , Mediadores da Inflamação/metabolismo , Masculino , Camundongos , Espécies Reativas de Oxigênio/metabolismo
20.
Mol Cell Biochem ; 403(1-2): 287-99, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25701356

RESUMO

FGF21 is recently discovered with pleiotropic effects on glucose and lipid metabolism. However, the potential protective effect of FGF21 against D-gal-induced injury in the liver has not been demonstrated. The aim of this study is to investigate the pathophysiological role of FGF21 on hepatic oxidative injury and apoptosis in mice induced by D-gal. The 3-month-old Kunming mice were subcutaneously injected with D-gal (180 mg kg(-1) d(-1)) for 8 weeks and administered simultaneously with FGF21 (5 or 1 mg kg(-1) d(-1)). Our results showed that the administration of FGF21 significantly alleviated histological lesion including structure damage, degeneration, and necrosis of hepatocytes induced by D-gal, and attenuated the elevation of liver injury markers, serum AST, and ALP in a dose-dependent manner. FGF21 treatment also suppressed D-gal-induced profound elevation of ROS production and oxidative stress, as evidenced by an increase of the MDA level and depletion of the intracellular GSH level in the liver, and restored the activities of antioxidant enzymes SOD, CAT, GSH-Px, and T-AOC. Moreover, FGF21 treatment increased the nuclear abundance of Nrf2 and subsequent up regulation of several antioxidant genes. Furthermore, a TUNEL assay showed that D-gal-induced apoptosis in the mouse liver was significantly inhibited by FGF21. The expression of caspase-3 was markedly inhibited by the treatment of FGF21 in the liver of D-gal-treated mice. The levels of PI3K and PBK/Akt were also largely enhanced, which in turn inactivated pro-apoptotic signaling events, restoring the balance between pro- and anti-apoptotic Bcl-2 and Bax proteins in the liver of D-gal-treated mice. In conclusion, these results suggest that FGF21 protects the mouse liver against D-gal-induced hepatocyte oxidative stress via enhancing Nrf2-mediated antioxidant capacity and apoptosis via activating PI3K/Akt pathway.


Assuntos
Apoptose/efeitos dos fármacos , Fatores de Crescimento de Fibroblastos/farmacologia , Fígado/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Substâncias Protetoras/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Caspase 3/metabolismo , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Ativação Enzimática/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Fígado/enzimologia , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Transporte Proteico/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo
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