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1.
Molecules ; 29(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38611812

RESUMO

Antibiotic resistance has emerged as a grave threat to global public health, leading to an increasing number of treatment failures. Antimicrobial peptides (AMPs) are widely regarded as potential substitutes for traditional antibiotics since they are less likely to induce resistance when used. A novel AMP named Brevinin-1BW (FLPLLAGLAASFLPTIFCKISRKC) was obtained by the Research Center of Molecular Medicine of Yunnan Province from the skin of the Pelophylax nigromaculatus. Brevinia-1BW had effective inhibitory effects on Gram-positive bacteria, with a minimum inhibitory concentration (MIC) of 3.125 µg/mL against Enterococcus faecalis (ATCC 29212) and 6.25 µg/mL against both Staphylococcus aureus (ATCC 25923) and multidrug-resistant Staphylococcus aureus (ATCC 29213) but had weaker inhibitory effects on Gram-negative bacteria, with a MIC of ≥100 µg/mL. Studies using scanning electron microscopy (SEM) and flow cytometry have revealed that it exerts its antibacterial activity by disrupting bacterial membranes. Additionally, it possesses strong biofilm inhibitory and eradication activities as well as significant lipopolysaccharide (LPS)-binding activity. Furthermore, Brevinin-1BW has shown a significant anti-inflammatory effect in LPS-treated RAW264.7 cells. In conclusion, Brevinin-1BW is anticipated to be a promising clinical agent with potent anti-Gram-positive bacterial and anti-inflammatory properties.


Assuntos
Lipopolissacarídeos , Staphylococcus aureus Resistente à Meticilina , China , Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Peptídeos Antimicrobianos
2.
Int J Mol Sci ; 24(23)2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38069041

RESUMO

Gastrointestinal cancer is a common clinical malignant tumor disease that seriously endangers human health and lacks effective treatment methods. As part of the innate immune defense of many organisms, antimicrobial peptides not only have broad-spectrum antibacterial activity but also can specifically kill tumor cells. The positive charge of antimicrobial peptides under neutral conditions determines their high selectivity to tumor cells. In addition, antimicrobial peptides also have unique anticancer mechanisms, such as inducing apoptosis, autophagy, cell cycle arrest, membrane destruction, and inhibition of metastasis, which highlights the low drug resistance and high specificity of antimicrobial peptides. In this review, we summarize the related studies on antimicrobial peptides in the treatment of digestive tract tumors, mainly oral cancer, esophageal cancer, gastric cancer, liver cancer, pancreatic cancer, and colorectal cancer. This paper describes the therapeutic advantages of antimicrobial peptides due to their unique anticancer mechanisms. The length, net charge, and secondary structure of antimicrobial peptides can be modified by design or modification to further enhance their anticancer effects. In summary, as an emerging cancer treatment drug, antimicrobial peptides need to be further studied to realize their application in gastrointestinal cancer diseases.


Assuntos
Antineoplásicos , Neoplasias Gastrointestinais , Neoplasias Gástricas , Humanos , Peptídeos Antimicrobianos , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/uso terapêutico , Peptídeos Catiônicos Antimicrobianos/química , Neoplasias Gastrointestinais/tratamento farmacológico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/química , Neoplasias Gástricas/tratamento farmacológico , Antibacterianos/farmacologia
4.
Artigo em Inglês | MEDLINE | ID: mdl-37883762

RESUMO

Cerebral infarction is characterized by a high morbidity, disability, and fatality rate. This study explored the relationship between serum ß2 microglobulin (ß2-MG), HGF, lipoprotein-associated phospholipase A2 (Lp-PLA2) and carotid atherosclerosis in patients with hypertension combined with cerebral infarction and their prognostic value. A total of 320 patients with cerebral infarction complicated with hypertension who were hospitalized from January 2015 to January 2020 were collected. HGF, Lp-PLA2 and ß2-MG levels were detected. Plaque score (Crouse score) was the patient's cumulative plaque thickness measurements. Additionally, the maximum plaque thickness and the number of plaques were measured.. The correlation was found between high ß2-MG levels and the poor prognosis (HR: 1.29, 95% CI: 1.03-1.52, P = .022). Patients who had elevated levels of HGF were also less likely to have a positive outcome (HR: 1.38, 95% CI: 1.26-1.56, P = .015). High Lp-PLA2 levels were associated with a worse prognosis than low levels (HR: 1.74, 95% CI: 1.29-2.32, P = .015). In conclusion, the levels of ß2-MG, HGF, and Lp-PLA2 in patients with hypertension combined with cerebral infarction were substantially linked with carotid plaques.

5.
Micromachines (Basel) ; 14(7)2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37512731

RESUMO

A high-precision current-mode bandgap reference (BGR) circuit with a high-order temperature compensation is presented in this paper. In order to achieve a high-precision BGR circuit, the equation of the nonlinear current has been modified and the high-order term of the current flowing into the nonlinear compensation bipolar junction transistor (NLCBJT) is compensated further. According to the modified equation, two solutions are designed to improve the output accuracy of BGR circuits. The first solution is to divide the NLCBJT branch into two branches to reduce the coefficient of the nonlinear temperature compensation current. The second solution is to inject the nonlinear current into the two branches based on the first one to further eliminate the temperature coefficient (TC) of the current flowing into the NLCBJT. The proposed BGR circuit has been designed using the Semiconductor Manufacturing International Corporation (SMIC) 55 nm CMOS process. The simulation results show that the variations in currents flowing into NLCBJTs improved from 148.41 nA to 69.35 nA and 7.4 nA, respectively, the TC of the output reference current of the proposed circuit is approximately 3.78 ppm/°C at a temperature range of -50 °C to 120 °C with a supply voltage of 3.3 V, the quiescent current consumption of the entire BGR circuit is 42.13 µA, and the size of the BGR layout is 0.044 mm2, leading to the development of a high-precision BGR circuit.

6.
Open Life Sci ; 17(1): 1519-1530, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36448063

RESUMO

Ischemic stroke (IS), usually caused due to an abrupt blockage of an artery, is the leading cause of disability and the second leading cause of death worldwide. The association of the C-reactive protein (CRP) gene (s3093059 T/C and rs1205 C/T) polymorphisms and IS susceptibility has been widely studied, but the results remain inconsistent. Our study aimed to assess the association between CRP gene (s3093059 T/C and rs1205 C/T) polymorphisms and IS risk. PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure, and WanFang databases were searched up to April 2022 to identify eligible studies. The Newcastle-Ottawa scale (NOS) score was calculated to assess study quality. The odd ratios (ORs) with a 95% confidence interval (CI) were calculated to assess the association between CRP gene (rs3093059 T/C and rs1205 C/T) polymorphisms and IS risk. Eighteen case-control studies with 6339 cases and 29580 controls were identified. We found that CRP (s3093059 T/C and rs1205 C/T) polymorphism was not significantly associated with the risk of IS in any genetic model (recessive model: OR 1.00, 95% CI 0.79-1.26; OR 1.06, 95% CI 0.90-1.25). When stratified analysis by country, genotype method, source of controls, and NOS score, still no statistically significant association was found. Our study indicated that the CRP (rs3093059 T/C and rs1205 C/T) polymorphisms were not associated with the susceptibility to IS.

7.
Front Bioeng Biotechnol ; 10: 977159, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36425652

RESUMO

Background and Purpose: Chronic wound infections and the development of antibiotic resistance are serious clinical problems that affect millions of people worldwide. Cathelicidin-DM, an antimicrobial peptide from Duttaphrynus melanostictus, has powerful antimicrobial activity and wound healing efficacy. So, it could be a potential candidate to address this problem. In this paper, we investigate the wound healing mechanism of cathelicidin-DM to establish a basis for preclinical studies of the drug. Experimental Approach: The effects of cathelicidin-DM on cell proliferation and migration, cytokines, and mitogen-activated protein kinase (MAPK) signaling pathways were examined. Then mice whole skin wound model was constructed to evaluate the wound healing activity of cathelicidin-DM, and further histological changes in the wounds were assessed by hematoxylin-eosin staining (H&E) and immunohistochemical assays. Key Results: Cathelicidin-DM promotes the proliferation of HaCaT, HSF, and HUVEC cells in a concentration-dependent manner and the migration of HSF, HUVEC, and RAW.264.7 cells. Moreover,cathelicidin-DM can involve in wound healing through activation of the MAPK signaling pathway by upregulating phosphorylation of ERK, JNK, and P38. However, cathelicidin-DM didn't affect the secretion of IL-6 and TNF-α. At the animal level, cathelicidin-DM accelerated skin wound healing and early debridement in mice as well as promoted re-epithelialization and granulation tissue formation, α-SMA expression, and collagen I deposition in mice. Conclusion and Implications: Our data suggest that cathelicidin-DM can be engaged in the healing of infected and non-infected wounds through multiple pathways, providing a new strategy for the treatment of infected chronic wounds.

8.
Micromachines (Basel) ; 13(10)2022 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-36295947

RESUMO

A novel output-capacitorless low-dropout regulator (OCL-LDO) with an embedded slew-rate-enhancement (SRE) circuit is presented in this paper. The SRE circuit adopts a transient current-boost strategy to improve the slew rate at the gate of the power transistor when a large voltage spike at the output is detected. In addition, a feed-forward transconductance cell is introduced to form a push−pull output structure with the power transistor. The simulation results show that the maximum transient output voltage variation is 23.5 mV when the load current ILOAD is stepped from 0 to 100 mA in 100 ns with a load capacitance of 100 pF, and the settling time is 1.2 µs. The proposed OCL-LDO consumes a quiescent current of 30 µA and has a dropout voltage of 200 mV for the maximum output current of 100 mA.

9.
Micromachines (Basel) ; 13(10)2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36296021

RESUMO

A fully integrated low-dropout (LDO) regulator with improved load regulation and transient responses in 40 nm technology is presented in this paper. Combining adjustable threshold push-pull stage (ATPS) and master-slave power transistors topology, the proposed LDO maintains a three-stage structure within the full load range. The proposed structure ensures the steady-state performance of LDO and achieves 0.017 mV/mA load regulation. The ATPS consumes little quiescent current at light load current condition, and the turn-on threshold of the ATPS can be adjusted by a current source. Once the value of current source is set, the turn-on threshold is also determined. A benefit of the proposed structure is that the LDO can be stable from 0 to 100 mA load current with a maximum 100 pF parasitic load capacitance and a 0.7 pF compensation capacitor. It also shows good figure of merit (FOM) without an extra transient enhanced circuit. For the maximum 100 mA load transient with 100 ns edge time, the undershoot and overshoot are less than 33 mV. The dropout voltage of the regulator is 200 mV with input voltage of 1.1 V. The total current consumption of the LDO was 24.6 µA at no load.

10.
J Neurol ; 269(11): 5787-5797, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35829759

RESUMO

Sarcopenia has an insidious start that can induce physical malfunction, raise the risk of falls, disability, and mortality in the old, severely impair the aged persons' quality of life and health. More and more studies have demonstrated that sarcopenia is linked to neurological diseases in recent years. This review examines the advancement of sarcopenia and neurological illnesses research.


Assuntos
Pessoas com Deficiência , Doenças do Sistema Nervoso , Sarcopenia , Acidentes por Quedas , Idoso , Humanos , Doenças do Sistema Nervoso/complicações , Doenças do Sistema Nervoso/epidemiologia , Doenças do Sistema Nervoso/terapia , Qualidade de Vida , Sarcopenia/epidemiologia , Sarcopenia/etiologia , Sarcopenia/terapia
11.
Dalton Trans ; 50(34): 11804-11813, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34369502

RESUMO

Two-phase Ca2+-doped LaVO4:Eu3+ nanocrystals were prepared through a hydrothermal method with the help of SOD CITR and EDTA surfactants. The phase and morphology of the products were characterized by XRD and TEM, and the fluorescence performances were also recorded. The results indicated that Ca2+ ions were doped into the LaVO4:Eu3+ host lattice, impeding the aggregation of the nanocrystals and enhancing the luminescence intensity. The morphology transformation process and luminescence enhancement were systematacially investigated. The fluorescence intensity of the two selected samples could be completely quenched by Fe3+ ions without the disturbance of other ions, with the mechanism being due to the adsorption of Fe3+ ions onto the grains and a subsequent energy transfer from Eu3+ to Fe3+. Therefore, the present two Ca2+-doped LaVO4:Eu3+ samples can be applied as appropriate candidates for detecting Fe3+ ions with agility and sensitivity in aqueous solution.

12.
Waste Manag ; 117: 81-92, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32818811

RESUMO

China's automobile industry is developing rapidly, but the recycling rate of end-of-life vehicles has been low. In 2018, the recovery rate of end-of-life passenger vehicles was less than 18% of the scrapped amount. Dynamic material flow analysis can predict the amount of end-of-life passenger cars in China in the future, and analyze the flow of materials in recycling system. Life cycle assessment can be used to quantify greenhouse gas emissions. Therefore, this paper integrates these two methods into the model construction of recycling decision system. Meanwhile, sensitivity analysis of the important factors affecting the efficiency of the recovery system is carried out. Finally, the main recovery indexes of the system are predicted under three scenarios: low-speed, medium speed and high-speed development, which are set based on scrap volume, standard recovery rate, proportion of assembly into remanufacturing and carbon tax price. The research results show that in 2018, 656.9 kg/vehicle of iron, 150.2 kg/vehicle of aluminum and 7.9 kg/vehicle of copper are recovered from end-of-life passenger car in China, and the carbon emission during the recovery process is 651.1 kg of CO2eq/vehicle, with a total emission reduction of 3816.1 kgCO2eq/vehicle compared with the original production, and the economic benefit is about 5055.5 yuan/vehicle. The scenario prediction results show that by 2050, from the low-speed development scenario to the high-speed development scenario, the total amount of iron, aluminum and copper recovered rise from 3.96 million tons, 915 thousand tons and 46 thousand tons to 697 thousand tons, 1.61 million tons and 80 thousand tons respectively throughout the year. The carbon emission in the recovery process rise from 4.98 thousand tons to 9.32 million tons. Compared with the original production, the carbon emission reduction increases from 2.21 million tons to 38.3 million tons, the economic benefit increases from 58.9 billion yuan to 118.8 billion yuan, and the comprehensive benefit increases from 57 billion yuan to 111.6 billion yuan.


Assuntos
Gases de Efeito Estufa , Reciclagem , Automóveis , China , Indústrias
13.
J Environ Manage ; 255: 109859, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32063319

RESUMO

China's paper industry development is rapid, but the recycling rate of China's waste paper has been low all the time. Meanwhile, material flow analysis can help determine the flow of waste paper, and life cycle assessment (LCA) is the methodological framework for quantifying greenhouse gas emissions. Therefore, present study integrates these two methods into the model construction of China's waste paper recycling decision system. Present study constructs a benchmark model of China's waste paper recycling decision system in 2017, focusing on the impact of nonstandard waste paper recycling on the economic and environmental benefits of China's domestic waste paper recycling system. This model construction is followed by sensitivity analysis of the relevant parameters affecting the efficiency of the waste paper recycling system. Finally, present study forecasts the system's economic benefits and greenhouse gas (GHG) emissions in the context of integrating and regulating nonstandard recycling vendors. The results show that the economic benefit of China's waste paper recycling in 2017 is approximately 458.3 yuan/t and that the GHG emissions are 901.1 kgCO2eq. The standard recovery rate and nonstandard recovery acceptance rate will both have a significant impact on the system's economic benefits and improve the GHG emissions structure. In the context of integrating nonstandard recycling enterprises and individual recycling vendors, the economic benefits will rise to 3312.5 yuan/t in 2030, while GHG emissions will rise to 942.9 kgCO2eq. Present study can play a certain guiding role for policy makers in formulating waste paper recycling industry specifications and formulating relevant policies.


Assuntos
Gases de Efeito Estufa , Reciclagem , China , Efeito Estufa , Indústrias
14.
World J Gastroenterol ; 18(7): 654-61, 2012 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-22363136

RESUMO

AIM: To evaluate the hepatoprotective roles of (Z)-5-(4-methoxybenzylidene)thiazolidine-2,4-dione (SKLB010) against carbon tetrachloride (CCl4)-induced acute and chronic liver injury and its underlying mechanisms of action. METHODS: In the first experiment, rats were weighed and randomly divided into 5 groups (five rats in each group) to assess the protective effect of SKLB010 on acute liver injury. For induction of acute injury, rats were administered a single intraperitoneal injection of 2 mL/kg of 50% (v/v) CCl4 dissolved in olive oil (1:1). Group 1 was untreated and served as the control group; group 2 received CCl4 for induction of liver injury and served as the model group. In groups 3, 4 and 5, rats receiving CCl4 were also treated with SKLB010 at doses of 25, 50 and 100 mg/kg, respectively. Blood samples were collected at 6, 12 and 24 h after CCl4 intoxication to determine the serum activity of alanine amino transferase. Tumour necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß) were determined using enzyme-linked immunosorbent assay. At 24 h after CCl4 injection, liver fibrogenesis was evaluated by hematoxylin-eosin (HE) staining and immunohistochemical analyses. Cytokine transcript levels of TNF-α, IL-1ß and inducible nitric oxide synthase in the liver tissues of rats were measured using a reverse transcriptase reverse transcription-polymerase chain reaction technique. In the second experiment, rats were randomly divided into 2 groups (15 rats in each group), and liver injury in the CCl4-administered groups was induced by a single intraperitoneal injection of 2 mL/kg of 50% (v/v) CCl4 dissolved in olive oil (1:1). The SKLB010-treated groups received oral 100 mg/kg SKLB010 before CCl4 administration. Five rats in each group were sacrificed at 2 h, 6 h, 12 h after CCl4 intoxication and small fortions of livers were rapidly frozen for extraction of total RNA, hepatic proteins and glutathione (GSH) assays. In the hepatic fibrosis model group, rats were randomly divided into 2 groups (5 rats each group). Rats were injected intraperitoneally with a mixture of CCl4 (1 mL/kg body weight) and olive oil [1:1 (v/v)] twice a week for 4 wk. In the SKLB010-treated groups, SKLB010 (100 mg/kg) was given once daily by oral gavage for 4 wk after CCl4 administration. The rats were sacrificed one week after the last injection and the livers from each group were harvested and fixed in 10% formalin for HE and immunohistochemical staining. RESULTS: In this rat acute liver injury model, oral administration of SKLB010 blocked liver tissue injury by down-regulating the serum levels of alanine aminotransferase, suppressing inflammatory infiltration to liver tissue, and improving the histological architecture of liver. SKLB010 inhibited the activation of NF-κB by suppressing the degradation of IκB, and prevented the secretion of pro-inflammatory mediators such as tumor necrosis factor-α, interleukin-1ß, and the reactive free radical, nitric oxide, at the transcriptional and translational levels. In this chronic liver fibrosis model, treatment with 100 mg/kg per day SKLB010 attenuated the degree of hepatic fibrosis and area of collagen, and blocked the accumulation of smooth-muscle actin-expressed cells. CONCLUSION: These results suggest that SKLB010 is a potent therapeutic agent for the treatment of CCl4-induced hepatic injury.


Assuntos
Tetracloreto de Carbono/farmacologia , Fígado/efeitos dos fármacos , Fígado/patologia , Tiazolidinedionas/farmacologia , Animais , Feminino , Fibrose/induzido quimicamente , Fibrose/patologia , Estrutura Molecular , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Tiazolidinedionas/química
15.
J Gastroenterol Hepatol ; 27(5): 966-73, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21913985

RESUMO

BACKGROUND AND AIM: (Z)2-(5-(4-methoxybenzylidene)-2, 4-dioxothiazolidin-3-yl) acetic acid (MDA) is an aldose reductase (AR) inhibitor. Recent studies suggest that AR contributes to the pathogenesis of inflammation by affecting the nuclear factor κB (NF-κB)-dependent expression of cytokines and chemokines and therefore could be a novel therapeutic target for inflammatory pathology. The current study evaluated the in vivo role of MDA in protecting the liver against injury and fibrogenesis caused by CCl(4) in rats, and the underlying mechanisms. METHODS: A single injection of CCl(4) induced acute hepatitis, and repeated injections were used to induce hepatic fibrosis in rats. Therapeutic efficacy was assessed by comparison of the severity of hepatic injury and fibrosis in MDA-treated rats versus untreated controls. RESULTS: MDA significantly protected the liver from injury by reducing the activity of serum alanine aminotransferase, and improving the histological architecture of the liver. MDA modulated NF-κB-dependent activation of inflammatory cytokines by reducing hepatic mRNA levels of tumor necrosis factor-α, interleukin-1ß, inducible nitric oxide (NO) synthase and transforming growth factor-ß. In addition, MDA attenuated oxidative stress by increasing the content of hepatic glutathione. These favorable changes were associated with suppressed hepatic NF-κB activation by MDA. MDA treatment improved liver fibrosis in rats that received repeated CCl(4) injections. In vitro, MDA attenuated phosphorylation of IκB and activation of NF-κB, and thus prevented biosynthesis of NO in lipopolysaccharide-activated RAW264.7 cells. CONCLUSIONS: The present study suggests that AR is a novel therapeutic anti-inflammatory target for the treatment of hepatitis and liver fibrosis.


Assuntos
Aldeído Redutase/antagonistas & inibidores , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Inibidores Enzimáticos/uso terapêutico , Cirrose Hepática Experimental/metabolismo , Cirrose Hepática Experimental/prevenção & controle , Tiazolidinedionas/uso terapêutico , Alanina Transaminase/sangue , Animais , Tetracloreto de Carbono , Células Cultivadas , Doença Hepática Induzida por Substâncias e Drogas/patologia , Inibidores Enzimáticos/farmacologia , Glutationa/metabolismo , Proteínas I-kappa B/metabolismo , Interleucina-1beta/metabolismo , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática Experimental/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , NF-kappa B/efeitos dos fármacos , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Estresse Oxidativo/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Tiazolidinedionas/farmacologia , Fator de Crescimento Transformador beta/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
16.
Eur J Pharmacol ; 659(2-3): 244-51, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21463618

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is a frequent kind of metabolic syndrome, which included a wide spectrum of liver damage and closely associated with insulin resistance and other metabolic syndromes such as obesity, type II diabetes, hyperglycemia, etc. Recently, a new series of PPARγ ligands based on barbituric acid has been designed, in which 5-(4-(benzyloxy)benzylidene)pyrimidine-2,4,6(1H,3H,5H)-trione (SKLB102) showed a high affinity with PPARγ. The current study aimed to evaluate the protective effect of SKLB102 on NAFLD and investigate the underlying mechanisms. In vivo, oral administration of SKLB102 prevented the pathological development, as demonstrated by reducing liver weight and visceral fat effectively, decreasing the serum levels of alanine transaminase, TNF-α and glucose, diminishing the hepatic triglyceride and malondialdehyde content and recovering the abnormal down-regulation of LDL. Histological examination of liver sections by Oil Red O and H&E staining confirmed the protective effect of SKLB102 on NAFLD. Furthermore, SKLB102 elevated the serum level of adiponectin, reduced the serum level of leptin and prevented insulin resistance. Western blots indicated that SKLB102 increased the hepatic AMPK activities and CPT-1 expression. In vitro, SKLB102 showed the ability of significantly enhancing adiponectin expression and inhibiting leptin expression in 3T3-L1 adipocytes. Furthermore, SKLB102 could promote glucose consumption in HepG2 cells in the presence of 0.1 µM insulin. In conclusion, our current study provided strong evidence that SKLB102 had potent ability to reduce fat deposition and protect liver against NAFLD through regulating adipocytokine expression and preventing insulin resistance, which might be of protective value for the prevention of NAFLD.


Assuntos
Adipocinas/metabolismo , Barbitúricos/química , Barbitúricos/farmacologia , Fígado Gorduroso/prevenção & controle , Regulação da Expressão Gênica/efeitos dos fármacos , Resistência à Insulina , PPAR gama/agonistas , Células 3T3-L1 , Proteínas Quinases Ativadas por AMP/metabolismo , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Animais , Carnitina O-Palmitoiltransferase/metabolismo , Diferenciação Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Células Hep G2 , Humanos , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Masculino , Malondialdeído/metabolismo , Camundongos , Hepatopatia Gordurosa não Alcoólica , Ratos , Ratos Wistar , Triglicerídeos/metabolismo , Regulação para Cima/efeitos dos fármacos
17.
J Med Chem ; 54(7): 2060-8, 2011 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-21381754

RESUMO

Twenty-two compounds based on thiazolidine-2,4-dione moiety were synthesized and evaluated for the inhibitory potency on the production of nitric oxide (NO), inducible nitric oxide synthase (iNOS) activity, and the generation of prostaglandin E(2) (PEG(2)). (Z)-N-(3-chlorophenyl)-2-(4-((2,4-dioxothiazolidin-5-ylidene) methyl) phenoxy) acetamide (3I), superior to the commercial anti-inflammatory drug indomethacin, significantly inhibited iNOS activity (IC(50) = 8.66 µM), iNOS-mediated NO, and cyclooxygenase (COX)-2-derived PGE(2) production (IC(50) = 4.16 and 23.55 µM, respectively) on lipopolysaccharide (LPS)-induced RAW 264.7 cells. Docking study revealed that 3I was perfectly docking into the active site of murine iNOS and suppressed the expression of iNOS protein as evidenced by Western blot analysis. At the dose of 50 mg/kg, oral administration of 3I possessed protective properties in both carrageenan-induced paw edema and adjuvant-induced arthritis rat models.


Assuntos
Anti-Inflamatórios/síntese química , Anti-Inflamatórios/farmacologia , Compostos de Benzilideno/síntese química , Compostos de Benzilideno/farmacologia , Tiazolidinedionas/síntese química , Tiazolidinedionas/farmacologia , Animais , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios/toxicidade , Artrite Experimental/tratamento farmacológico , Compostos de Benzilideno/uso terapêutico , Compostos de Benzilideno/toxicidade , Carragenina/farmacologia , Linhagem Celular , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/biossíntese , Relação Dose-Resposta a Droga , Edema/induzido quimicamente , Edema/tratamento farmacológico , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Inflamação/tratamento farmacológico , Inflamação/enzimologia , Inflamação/metabolismo , Concentração Inibidora 50 , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Modelos Moleculares , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/química , Óxido Nítrico Sintase Tipo II/metabolismo , Conformação Proteica , Ratos , Tiazolidinedionas/uso terapêutico , Tiazolidinedionas/toxicidade
18.
Biol Pharm Bull ; 34(2): 219-25, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21415531

RESUMO

Idiopathic pulmonary fibrosis is regarded as a lethal chronic disease accompanied with excessive collagen disposition. In the early stage, monocyte chemotactic protein-1 (MCP-1) plays a crucial role in the process. Our previously screening with a vitro assay through inhibition of chemotaxis of RAW264.7 cells stimulated by MCP-1 proved that several analogues of thiazolidinediones, especially (Z)-5-(4-methoxybenzylidene)thiazolidine-2,4-dione (SKLB010), had potency of protecting acute liver injury in vivo without obvious toxicity. The present study aimed to investigate the preventive effect of SKLB010 in bleomycin-induced pulmonary fibrosis and further explore the underlying mechanisms. Bleomycin (BLM) was injected intratracheally at a single dose of 5 U kg(-1) for pulmonary fibrosis induction. SKLB010 (25, 50 mg/kg/d) was respectively administrated by gavages 1 d prior to BLM administration and continued to the end of the study (for 4 weeks). Our results demonstrated that SKLB010 diminished the increase of macrophage, neutrophil and lymphocyte counts as well as the levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß, and IL-6 in bronchoalveolar lavage fluid on day 14 (p<0.05). Moreover, oral gavages of SKLB010 also ameliorated histological changes and significantly suppressed collagen deposition on day 28. The treatment with SKLB010 exerted approximately 34.6% the hydroxyproline content reduction for 25 mg/kg dose and 56.7% reduction for 50 mg/kg dose in contrast to bleomycin-induced group (p<0.05). Meanwhile, SKLB010 inhibited the overexpression of tumor growth factor (TGF)-ß1 and Smad3 in a dose-dependent manner. In conclusion, our results showed that SKLB010 could attenuate the BLM-induced pulmonary fibrosis in vivo and therefore be a promising anti-fibrogenic candidate.


Assuntos
Colágeno/metabolismo , Citocinas/metabolismo , Hidroxiprolina/metabolismo , Pulmão/efeitos dos fármacos , Fibrose Pulmonar/prevenção & controle , Tiazolidinedionas/uso terapêutico , Animais , Bleomicina , Líquido da Lavagem Broncoalveolar , Linhagem Celular , Relação Dose-Resposta a Droga , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/patologia , Linfócitos/metabolismo , Macrófagos/metabolismo , Camundongos , Neutrófilos/metabolismo , Fibrose Pulmonar/imunologia , Proteína Smad3/metabolismo , Tiazolidinedionas/farmacologia , Fator de Crescimento Transformador beta1/metabolismo
19.
Eur J Med Chem ; 46(6): 2003-10, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21429633

RESUMO

Forty-four barbituric acid or thiobarbituric acid derivatives were synthesized and evaluated for their effects on adipogenesis of 3T3-L1 adipocytes by measuring the expression of adiponectin in vitro. Four compounds (3a, 3o, 3s, 4t) were found to increase the expression of adiponectin and lower the leptin level in 3T3-L1 adipocytes at respective concentration of 10 µM. Among them, 3s showed the most efficacious. Oral administration of 3s effectively reduced body weight, liver weight, and visceral fat and regulated serum levels of biochemical markers in the high-fat/diet-induced Wistar rats. Histopathological evaluation of liver sections by Oil Red O and H&E staining confirmed 3s as a potent, orally active molecule for reducing fat deposition against non-alcoholic fatty liver disease.


Assuntos
Adipogenia/efeitos dos fármacos , Barbitúricos/química , Barbitúricos/farmacologia , Fígado Gorduroso/tratamento farmacológico , Tiobarbitúricos/síntese química , Tiobarbitúricos/farmacologia , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Adiponectina/biossíntese , Animais , Barbitúricos/síntese química , Diferenciação Celular/efeitos dos fármacos , Modelos Animais de Doenças , Leptina/biossíntese , Masculino , Camundongos , Estrutura Molecular , Hepatopatia Gordurosa não Alcoólica , Ratos , Ratos Wistar , Estereoisomerismo , Relação Estrutura-Atividade , Tiobarbitúricos/química
20.
Cancer Res ; 70(17): 6849-58, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20660714

RESUMO

The pyrrolobenzodiazepines (PBD) are naturally occurring antitumor antibiotics, and a PBD dimer (SJG-136, SG2000) is in phase II trials. Many potent PBDs contain a C2-endo-exo unsaturated motif associated with the pyrrolo C-ring. The novel compound SG2202 is a PBD dimer containing this motif. SG2285 is a water-soluble prodrug of SG2202 in which two bisulfite groups inactivate the PBD N10-C11 imines. Once the bisulfites are eliminated, the imine moieties can bind covalently in the DNA minor groove, forming an interstrand cross-link. The mean in vitro cytotoxic potency of SG2285 against human tumor cell lines is GI(50) 20 pmol/L. SG2285 is highly efficient at producing DNA interstrand cross-links in cells, but they form more slowly than those produced by SG2202. Cellular sensitivity to SG2285 was primarily dependent on ERCC1 and homologous recombination repair. In primary B-cell chronic lymphocytic leukemia samples, the mean LD(50) was significantly lower than in normal age-matched B and T lymphocytes. Antitumor activity was shown in several human tumor xenograft models, including ovarian, non-small cell lung, prostate, pancreatic, and melanoma, with cures obtained in the latter model with a single dose. Further, in an advanced-stage colon model, SG2285 administered either as a single dose, or in two repeat dose schedules, was superior to irinotecan. Our findings define SG2285 as a highly active cytotoxic compound with antitumor properties desirable for further development.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Pró-Fármacos/farmacologia , Animais , Benzodiazepinonas/farmacologia , Células CHO , Linhagem Celular Tumoral , Cricetinae , Cricetulus , Feminino , Humanos , Camundongos , Neoplasias/tratamento farmacológico , Pirróis/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
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