Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 47
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Pharmacol Res ; 153: 104657, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31982488

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease worldwide and constitutes a major risk factor for progression to cirrhosis, liver failure and hepatocellular carcinoma (HCC). The occurrence of NAFLD is closely associated with abnormal lipid metabolism and implies a high risk of type 2 diabetes and cardiovascular disease. Therefore, specific and effective drugs for the prevention and treatment of NAFLD are necessary. Hypericin (HP) is one of the main active ingredients of Hypericum perforatum L., and we previously revealed its protective role in islet ß-cells and its effects against type 2 diabetes. In this study, we aimed to explore the preventive and therapeutic effects of HP against NAFLD and the underlying mechanisms in vitro and in vivo. Here, we demonstrated that HP improved cell viability by reducing apoptosis and attenuated lipid accumulation in hepatocytes both in vitro and in vivovia attenuating oxidative stress, inhibiting lipogenesis and enhancing lipid oxidization. Thus, HP exhibited significant preventive and therapeutic effects against HFHS-induced NAFLD and dyslipidemia in mice. Furthermore, we demonstrated that HP directly bound to PKACα and activated PKA/AMPK signaling to elicit its effects against NAFLD, suggesting that PKACα is one of the drug targets of HP. In addition, the enhancing effect of HP on lipolysis in adipocytes through the activation of PKACα was also elucidated. Together, the conclusions indicated that HP, of which one of the targets is PKACα, has the potential to be used as a preventive or therapeutic drug against NAFLD or abnormal lipid metabolism in the future.

2.
Invest Ophthalmol Vis Sci ; 60(13): 4084-4096, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31574534

RESUMO

Purpose: To investigate whole transcriptional differences between proliferative diabetic retinopathy (PDR) neovascular membranes (NVMs) and retinas, and the regulatory genes participating in retinal neovascularization in PDR. Methods: We used high-throughput sequencing technology to capture the whole-genome gene expression levels of all participants, including 23 patients with PDR or branch retinal vein occlusion (BRVO), 3 normal retinal samples, and 2 retinal samples from type II diabetic (T2D) eyes by donation, followed by analyses of expression patterns using bioinformatics methods, then validation of the data by in situ hybridization and Western blotting. Results: We showed that transcriptional profiles of the NVMs were distinct from those of the retinas. Angiogenesis growth factors VEGFC, ANGPT1, ANGPT2, and EFNB2, and their receptors FLT4, TIE1, TIE2, and EPHB4, respectively, were overexpressed. Expression of VEGFA was highly upregulated in T2D retina, but low in the NVMs, while angiogenesis transcription factors, including ETS1 and ERG, were coordinately upregulated in NVMs. Conclusions: This study described a PDR neovascularization model in which pathological retina-secreted vascular endothelial growth factor A (VEGFA) enhanced the expression of a set of angiogenesis transcription factors and growth factors, to cooperatively induce the retinal neovascularization. Based on these results, novel potential therapeutic targets and biomarkers for PDR treatment and diagnosis are suggested.


Assuntos
Angiopoietina-1/metabolismo , Retinopatia Diabética/metabolismo , Efrina-B2/metabolismo , Neovascularização Retiniana/metabolismo , Fator C de Crescimento do Endotélio Vascular/metabolismo , Humanos , Receptor EphB4/metabolismo , Receptor de TIE-1/metabolismo , Receptor TIE-2/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Oclusão da Veia Retiniana/metabolismo , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/metabolismo
3.
Chem Pharm Bull (Tokyo) ; 67(10): 1076-1081, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31406093

RESUMO

Histone deacetylases (HDACs) are enzymes that play a key role in structural modification and gene expression. The overexpression of HDAC is associated with cancer, and thus inhibiting the enzyme could be an efficient cancer therapy. To discover new HDAC inhibitors (HDACis), we proposed an improved protocol combining a hierarchical pharmacophore search, molecular docking, and molecular dynamic simulations. The test results showed that the improved screening protocol effectively reduced the false-positive rates of drug-like chemicals. Based on the protocol, we obtained 16 hit compounds as potential HDACis from the Life Chemicals database. Enzyme inhibition experiments showed that two of the hit chemical compounds had HDAC-inhibitory effects. In vitro assays showed that Z165155756 could selectively inhibit the proliferation of cancer cells and specifically promoted apoptosis and induced G1/S phase arrest in A2780 cells. It may have potential therapeutic effects in ovarian cancer and is worthy of further investigation.


Assuntos
Antineoplásicos/análise , Antineoplásicos/farmacologia , Descoberta de Drogas , Inibidores de Histona Desacetilases/análise , Inibidores de Histona Desacetilases/farmacologia , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores de Histona Desacetilases/química , Histona Desacetilases/metabolismo , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Relação Estrutura-Atividade
4.
Int J Biol Sci ; 15(7): 1472-1487, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31337977

RESUMO

A decrease in islet ß-cell mass is closely associated with the development and progression of diabetes. Therefore, protection against ß-cell loss is an essential measure to prevent and treat diabetes. In this study, we investigated the protective effects of non-photoactivated hypericin, a natural compound, on ß-cells both in vitro and in vivo. In vitro, hypericin greatly improved INS-1 cell viability under high-glucose and high-fatty-acid conditions by inhibiting glucotoxicity- and lipotoxicity-induced apoptosis and nitric oxide (NO) production. Then, we further demonstrated that hypericin elicited its protective effects against glucotoxicity and lipotoxicity in INS-1 cells by attenuating the reduction in pancreatic duodenal homeobox-1 (PDX1) expression and Erk activity. In vivo, prophylactic or therapeutic use of hypericin inhibited islet ß-cell apoptosis and enhanced the anti-oxidative ability of pancreatic tissue in high-fat/high-sucrose (HFHS)-fed mice, thus alleviating ß-cell loss and maintaining or improving ß-cell mass and islet size. More importantly, hypericin treatment decreased fasting blood glucose, improved glucose intolerance and insulin intolerance, and alleviated hyperinsulinaemia in HFHS-fed mice. Therefore, hypericin showed preventive and therapeutic effects against HFHS-induced onset of type II diabetes in mice. Hypericin possesses great potential for development as an anti-diabetes drug in the future.

5.
FEBS J ; 286(18): 3718-3736, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31349381

RESUMO

Glucotoxicity or lipotoxicity leads to hyperglycemia and insulin secretion deficiency, which are important causes for the onset of type 2 diabetes mellitus (T2DM). Thus, the restoration of ß-cell function is a long-sought goal in diabetes research. Previous studies have implicated pancreatic and duodenal homeobox 1 gene (Pdx1) in ß-cell function and insulin secretion. In this study, we established a Pdx1 promoter-dependent luciferase system and identified the natural compound dracorhodin perchlorate (DP) as an effective promotor of Pdx1 expression. We further demonstrated that DP could significantly inhibit ß-cell apoptosis induced by 33 mm glucose or 200 µm palmitate by interfering with endoplasmic reticulum stress and mitochondrial pathways and enhance insulin secretion as well. These effects were associated with enhanced activities of Erk1/2, which in turn promoted Pdx1 expression and increased the ratio of Bcl2/Bax, since inhibition of the Erk1/2 pathway abolished the DP-induced expression of Pdx1 and suppression of apoptosis. In addition, our in vivo results in diabetic mice indicated that DP treatment lowered blood glucose, raised insulin levels, enhanced Pdx1 expression and increased islet size and number in the pancreas of diabetic mice. Our findings suggest that Pdx1 is a potential target molecule of DP in the treatment of T2DM via the inhibition of glucotoxicity- or lipotoxicity- induced ß-cell apoptosis and the attenuation of insulin secretion dysfunction.

6.
BMC Infect Dis ; 19(1): 439, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31109292

RESUMO

BACKGROUND: Brucellosis has extensive clinical spectrum, clinicians have insufficient understanding of the disease, and the misdiagnosis rate is still high. By collecting and analyzing the clinical characteristics of patients with brucellosis in Heilongjiang Province to provide guidance and reference for clinicians to make timely diagnosis and treatment. METHODS: The demographic and epidemiological characteristics, clinical features, complications, laboratory findings were retrospectively evaluated in 850 brucellosis patients admitted in the Department of Infectious Diseases of the First Affiliated Hospital of Harbin Medical University and the Second Hospital of Daqing from 2012 to 2017. RESULTS: Of the 850 patients, the most common clinical manifestations were fever (93.3%), joint pain (69.8%), sweating (45.2%), fatigue (38.6%), and splenomegaly (34.0%). Peripheral arthritis, spondylitis and epididymal-orchitis were the common complications. Of the 398 patients who were followed up and completed treatment, 22 (5.5%) had relapse. CONCLUSIONS: Brucellosis is a multisystem disease with diverse clinical manifestations. In areas where brucellosis is endemic, the possibility of the disease should be considered in patients with unexplained fever and joints pain. In addition, the high rate of relapse is mainly due to the misdiagnosis of complications, so local CT or MRI examination is necessary for patients with joint pain and low back pain. Timely diagnosis, early detection of complications are essential to improve the prognosis and reduce relapse.


Assuntos
Brucelose/diagnóstico , Adolescente , Adulto , Idoso , Artralgia/complicações , Brucelose/complicações , Brucelose/epidemiologia , Criança , Pré-Escolar , China/epidemiologia , Fadiga/complicações , Feminino , Febre/complicações , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Esplenomegalia/complicações , Adulto Jovem
7.
Sci Rep ; 9(1): 2350, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30787420

RESUMO

Histone deacetylases (HDACs) can enzymatically transferred acetyl functional group from protein or lysine residues of histone, so they can regulate the expression of lots of genes. Now HDACs are used as drug targets and many HDAC inhibitors (HDACis) were approved for cancer therapy or in clinical trials. However, the physiological mechanisms and regulatory processes of HDACi anti-cancer effects are largely unexplored and uncompleted. Here we use the virtual screening workflow obtained 25 hit compounds and ZINC24469384 can significantly inhibit HDAC activity while arrest cell cycle at G1/S phase and significantly induced HepG2 cell apoptosis, time-course RNA-seq demonstrate that HepG2 cells transcriptionally respond to ZINC24469384. Pathway analysis of DEGs and DASGs reveal that NR1H4 may play an important role in ZINC24469384-induced anti-proliferation effect and is dramatically alleviated by down-regulating the SOCS2 expression and promoting STAT3 phosphorylation in knockdown NR1H4 HepG2 cells. Analysis based on TCGA database indicated that NR1H4 and SOCS2 were downregulated in liver cancer, this suggest NR1H4 and SOCS2 may play an important role in tumorigenesis. These results indicated that ZINC24469384 is a novel benzamine lead compound of HDACi and provides a novel mechanism for HDACi to inhibit cancer.

8.
Mol Med Rep ; 18(6): 5726-5732, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30365118

RESUMO

Hepatitis B core antigen (HBcAg) possesses unusual immunologic features. However, the biological roles and mechanisms of HBcAg in dendritic cell proliferation and apoptosis remain to be elucidated. In the present study, DC2.4 cells were treated with different concentrations of HBcAg (10, 20 and 30 µg/ml). MTT assay and flow cytometry (Annexin V/propidium iodide analysis) were performed to investigate changes in cell proliferation and apoptosis. Western blot analysis was conducted to examine the changes in nuclear factor (NF)­κB and protein kinase C (PKC) signaling pathways. NF­κB inhibitor pyrrolidine dithiocarbamate (PDTC) and PKC inhibitor Chelerythrine were used to block these two signaling pathways. It was identified that HBcAg increased proliferation and decreased apoptosis in a dose­dependent manner. Western blotting results demonstrated that HBcAg upregulated p­PKC, p­IκB, p­P65, tumor necrosis factor­α and B­cell lymphoma 2 (Bcl­2) levels, and downregulated cleaved caspase 3, demonstrating that HBcAg activated the PKC and NF­κB signaling pathways. NF­κB inhibitor PDTC reduced the effects of HBcAg on DC2.4 proliferation (0.6 fold vs. 0.25 fold) and apoptosis (0.43 fold vs. 0.17 fold), and on Bcl­2 expression levels. PKC inhibitor Chelerythrine reduced the biological effects of HBcAg; it reduced proliferation (0.67 fold vs. 0.23 fold) and upregulated apoptosis (0.43 fold vs. 0.13 fold). Chelerythrine also blocked NF­κB activity and the HBcAg­induced Bcl­2 increase, suggesting the effect on Bcl­2 from HBcAg was dependent on the PKC/NF­κB signaling pathway. In conclusion, HBcAg promoted proliferation and inhibited apoptosis through the PKC/NF­κB/Bcl­2 signaling pathway in DC2.4 cells.


Assuntos
Apoptose , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , NF-kappa B/metabolismo , Proteína Quinase C/metabolismo , Transdução de Sinais , Apoptose/imunologia , Biomarcadores , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Células Dendríticas/efeitos dos fármacos , Relação Dose-Resposta a Droga , Antígenos do Núcleo do Vírus da Hepatite B/farmacologia , Humanos , Imunofenotipagem , Proteínas Recombinantes
9.
Sci Rep ; 8(1): 1479, 2018 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-29367618

RESUMO

Prohibitin 2 (PHB2), as a conserved multifunctional protein, is traditionally localized in the mitochondrial inner membrane and essential for maintenance of mitochondrial function. Here, we investigated the role of PHB2 in human rhabdomyosarcoma (RMS) RD cells and found substantial localization of PHB2 in the nucleolus. We demonstrated that PHB2 knockdown inhibited RD cell proliferation through inducing cell cycle arrest and suppressing DNA synthesis. Meanwhile, down-regulation of PHB2 also induced apoptosis and promoted differentiation in fractions of RD cells. In addition, PHB2 silencing led to altered nucleolar morphology, as observed by transmission electron microscopy, and impaired nucleolar function, as evidenced by down-regulation of 45S and 18S ribosomal RNA synthesis. Consistently, upon PHB2 knockdown, occupancy of c-Myc at the ribosomal DNA (rDNA) promoter was attenuated, while more myoblast determination protein 1 (MyoD) molecules bound to the rDNA promoter. In conclusion, our findings suggest that nucleolar PHB2 is involved in maintaining nucleolar morphology and function in RD cells by regulating a variety of transcription factors, which is likely to be one of the underlying mechanisms by which PHB2 promotes tumor proliferation and represses differentiation. Our study provides new insight into the pathogenesis of RMS and novel characterizations of the highly conserved PHB2 protein.


Assuntos
Nucléolo Celular/metabolismo , Proliferação de Células , RNA Ribossômico/genética , Proteínas Repressoras/metabolismo , Rabdomiossarcoma/patologia , Transcrição Genética , Apoptose , Diferenciação Celular , Humanos , Proteína MyoD/metabolismo , RNA Interferente Pequeno/genética , Proteínas Repressoras/antagonistas & inibidores , Proteínas Repressoras/genética , Rabdomiossarcoma/genética , Rabdomiossarcoma/metabolismo , Células Tumorais Cultivadas
10.
Apoptosis ; 22(11): 1404-1418, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28864870

RESUMO

The pro-inflammatory cytokine interleukin 6 (IL-6), via activating its downstream JAK/STAT3 and Ras/ERK signaling pathways, is involved in cell growth, proliferation and anti-apoptotic activities in various malignancies. To screen inhibitors of IL-6 signaling, we constructed a STAT3 and ERK dual-pathway responsive luciferase reporter vector (Co.RE). Among several candidates, the natural compound 20(S)-25-methoxyl-dammarane-3ß, 12ß, 20-triol (25-OCH3-PPD, GS25) was identified to clearly inhibit the luciferase activity of Co.RE. GS25 was confirmed to indeed inhibit activation of both STAT3 and ERK pathways and expression of downstream target genes of IL-6, and to predominantly decrease the viability of HepG2 cells via induction of cell cycle arrest and apoptosis. Interestingly, GS25 showed preferential inhibition of HepG2 cell viability relative to normal liver L02 cells. Further investigation showed that GS25 could not induce apoptosis and block activation of STAT3 and ERK pathways in L02 cells as efficiently as in HepG2 cells, which may result in differential effects of GS25 on malignant and normal liver cells. In addition, GS25 was found to potently suppress the expression of endogenous STAT3 at a higher concentration and dramatically induce p38 phosphorylation in HepG2 cells, which could mediate its anti-cancer effects. Finally, we demonstrated that GS25 also inhibited tumor growth in HepG2 xenograft mice. Taken together, these findings indicate that GS25 elicits its anti-cancer effects on HepG2 cells through multiple mechanisms and has the potential to be used as an inhibitor of IL-6 signaling. Thus, GS25 may be developed as a treatment for hepatocarcinoma with low toxicity on normal liver tissues as well as other inflammation-associated diseases.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Regulação Neoplásica da Expressão Gênica , Ginsenosídeos/farmacologia , Hepatoblastoma/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Fator de Transcrição STAT3/genética , Animais , Antineoplásicos Fitogênicos/síntese química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Proliferação de Células/efeitos dos fármacos , Feminino , Genes Reporter , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Ginsenosídeos/química , Células Hep G2 , Hepatoblastoma/genética , Hepatoblastoma/metabolismo , Hepatoblastoma/patologia , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Luciferases/genética , Luciferases/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Nus , Fator de Transcrição STAT3/agonistas , Fator de Transcrição STAT3/metabolismo , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
11.
Front Microbiol ; 8: 1738, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28955316

RESUMO

Streptococcus mutans has been reported as a primary cariogenic pathogen associated with dental caries. The bacteria can produce glucosyltransferases (Gtfs) to synthesize extracellular polysaccharides (EPSs) that are known as virulence factors for adherence and formation of biofilms. Therefore, an ideal inhibitor for dental caries is one that can inhibit planktonic bacteria growth and prevent biofilm formation. Bergenia crassifolia (L.), widely used as a folk medicine and tea beverage, has been reported to have a variety of bioactivities. The present study aimed to explore the effect of B. crassifolia (L.) leaf extracts on the biofilm of Streptococcus mutans. The B. crassifolia (L.) leaf extracts showed inhibitory effects by decreasing viability of bacteria within the biofilm, as evidenced by the XTT assay, live/dead staining assay and LDH activity assay, and could decrease the adherence property of S. mutans through inhibiting Gtfs to synthesize EPSs. In addition, the reduced quantity of EPSs and the inhibition of Gtfs were positively correlated with concentrations of test samples. Finally, the MTT assay showed that the extracts had no cytotoxicity against normal oral cells. In conclusion, the extracts and sub-extracts of B. crassifolia leaves were found to be antimicrobial and could reduce EPS synthesis by inhibiting activities of Gtfs to prevent bacterial adhesion and biofilm formation. Therefore, B. crassifolia leaves have potential to be developed as a drug to prevent and cure dental caries.

12.
Biochem Biophys Res Commun ; 491(3): 800-806, 2017 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-28705738

RESUMO

Histone deacetylases (HDACs) family has been widely reported as an important class of enzyme targets for cancer therapy. Much effort has been made in discovery of novel scaffolds for HDACs inhibition besides existing hydroxamic acids, cyclic peptides, benzamides, and short-chain fatty acids. Herein we set up an in-silico protocol which not only could detect potential Zn2+ chelation bonds but also still adopted non-bonded model to be effective in discovery of Class I HDACs inhibitors, with little human's subjective visual judgment involved. We applied the protocol to screening of Chembridge database and selected out 7 scaffolds, 3 with probability of more than 99%. Biological assay results demonstrated that two of them exhibited HDAC-inhibitory activity and are thus considerable for structure modification to further improve their bio-activity.


Assuntos
Inibidores de Histona Desacetilases/química , Histona Desacetilases/química , Histona Desacetilases/ultraestrutura , Modelos Químicos , Simulação de Acoplamento Molecular/métodos , Zinco/química , Sítios de Ligação , Quelantes/química , Simulação por Computador , Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos/métodos , Ativação Enzimática , Aprendizado de Máquina , Ligação Proteica , Mapeamento de Interação de Proteínas/métodos , Interface Usuário-Computador
13.
Biomacromolecules ; 18(8): 2306-2314, 2017 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-28654745

RESUMO

The capacity to specifically destroy cancer cells while avoiding normal tissue is urgently desirable in cancer treatment. Herein, a photothermal-trigger-released system serves as a photoacoustic imaging agent constructed by entrapping diketopyrrolopyrrole-based conjugated polymers and curcumin in a poly(ethylene glycol) (PEG)-protected thermoresponsive liposomal phospholipid bilayer. This lipid nanostructure can improve the bioavailability of hydrophobic agents for photothermal treatment with high efficiency and deliver the anticancer drug curcumin to the tumor site actuated by near-infrared (NIR) irradiation. A significantly enhanced combined therapeutic effect to HepG2 tumor-bearing mice was acquired in contrast to the result of single therapy alone. These liposomes with the capability of photoacoustic imaging, greater EPR-induced accumulation in tumor sites, and hyperthermia ablation for photothermal chemotherapy show potential for photoacoustic imaging-guided photothermal/chemo combined therapeutic applications.


Assuntos
Hipotermia Induzida , Cetonas , Neoplasias Experimentais , Técnicas Fotoacústicas , Fototerapia , Polietilenoglicóis , Pirróis , Animais , Células Hep G2 , Humanos , Cetonas/química , Cetonas/farmacologia , Lipossomos , Camundongos , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/terapia , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Pirróis/química , Pirróis/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Int J Mol Sci ; 18(4)2017 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-28394269

RESUMO

Ginkgolide A (GA) is a natural compound isolated from Ginkgo biloba and has been used to treat cardiovascular diseases and diabetic vascular complications. However, only a few studies have been conducted on the anti-inflammatory effects of GA. In particular, no related reports have been published in a common inflammation model of lipopolysaccharide (LPS)-stimulated macrophages, and the anti-inflammatory mechanisms of GA have not been fully elucidated. In the present study, we extensively investigated the anti-inflammatory potential of GA in vitro and in vivo. We showed that GA could suppress the expression of pro-inflammatory mediators (cyclooxygenase-2 (COX-2) and nitric oxide (NO) and pro-inflammatory cytokines (tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-1ß) in LPS-treated mouse peritoneal macrophages, mouse macrophage RAW264.7 cells, and differentiated human monocytes (dTHP-1) in vitro. These effects were partially carried out via downregulating Nuclear factor kappa-B (NF-κB), Mitogen-activated protein kinases (MAPKs) (p38 mitogen-activated protein kinase and extracellular signal-regulated kinase (ERK), but not c-Jun N-terminal kinase (JNK), and activating the AMP-activated protein kinase (AMPK) signaling pathway also seems to be important. Consistently, GA was also shown to inhibit the LPS-stimulated release of TNF-α and IL-6 in mice. Taken together, these findings suggest that GA can serve as an effective inflammatory inhibitor in vitro and in vivo.


Assuntos
Ginkgolídeos/farmacologia , Inflamação/prevenção & controle , Lactonas/farmacologia , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Animais , Western Blotting , Linhagem Celular , Linhagem Celular Tumoral , Ciclo-Oxigenase 2/metabolismo , Citocinas/sangue , Citocinas/genética , Citocinas/metabolismo , Feminino , Expressão Gênica/efeitos dos fármacos , Humanos , Inflamação/sangue , Inflamação/induzido quimicamente , Mediadores da Inflamação/sangue , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos , Macrófagos/metabolismo , Macrófagos Peritoneais/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos
15.
BMC Pharmacol Toxicol ; 17(1): 32, 2016 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-27443303

RESUMO

BACKGROUND: Histone deacetylases (HDACs) are promising therapeutic targets for the treatment of cancer, diabetes and other human diseases. HDAC inhibitors, as a new class of potential therapeutic agents, have attracted a great deal of interest for both research and clinical applications. Increasing efforts have been focused on the discovery of HDAC inhibitors and some HDAC inhibitors have been approved for use in cancer therapy. However, most HDAC inhibitors, including the clinically approved agents, do not selectively inhibit the deacetylase activity of class I and II HDAC isforms, and many suffer from metabolic instability. This study aims to identify new HDAC inhibitors by using a high-throughput virtual screening approach. METHODS: An integration of in silico virtual screening and in vitro experimental validation was used to identify novel HDAC inhibitors from a chemical database. RESULTS: A virtual screening workflow for HDAC inhibitors were created by integrating ligand- and receptor- based virtual screening methods. Using the virtual screening workflow, 22 hit compounds were selected and further tested via in vitro assays. Enzyme inhibition assays showed that three of the 22 compounds had HDAC inhibitory properties. Among these three compounds, ZINC12555961 significantly inhibited HDAC activity. Further in vitro experiments indicated that ZINC12555961 can selectively inhibit proliferation and promote apoptosis of cancer cells. CONCLUSIONS: In summary, our study presents three new and potent HDAC inhibitors and one of these HDAC inhibitors shows anti-proliferative and apoptosis-inducing activity against various cancer cell lines. These results suggest that the developed virtual screening workflow can provide a useful source of information for the screening and validation of new HDAC inhibitors. The new-found HDAC inhibitors are worthy to further and more comprehensive investigations.


Assuntos
Desenho de Drogas , Inibidores de Histona Desacetilases/química , Inibidores de Histona Desacetilases/farmacologia , Interface Usuário-Computador , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Avaliação Pré-Clínica de Medicamentos/métodos , Avaliação Pré-Clínica de Medicamentos/normas , Células Hep G2 , Humanos , Reprodutibilidade dos Testes
16.
Med Sci Monit ; 22: 1673-81, 2016 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-27188537

RESUMO

BACKGROUND Hepatitis B virus (HBV) is a hepatotropic virus that can infect extrahepatic tissue. Whether hematopoietic stem cells (HSCs) can be infected by HBV and serve as a potential virus reservoir is still unknown. In this study, the susceptibility of CD34+ HSCs to HBV was investigated. MATERIAL AND METHODS Cord blood-derived CD34+ HSCs were exposed to HBV in vitro, and immunocytochemistry, transmission electron microscopy, and RT-PCR were used to identify viral-related proteins and specific viral genomic sequences. Then, CD34+ HSCs were challenged by different titers of HBV, and intracellular and supernatant HBV DNA, and hepatitis B surface antigen (HBsAg) levels, were examined. In addition, CD34+ peripheral blood stem cells (PBSCs) from chronic HBV carriers were isolated and cultured, and HBV DNA levels were measured. RESULTS HBV-infected CD34+ cells showed positive signals for HBsAg by DAB staining and TRITC staining, and HBV particles were identified. RT-PCR results showed that the 403 bp PCR products corresponding to the amplified hepatitis B S gene fragment were observed in CD34+ HSCs infected by HBV. In addition, supernatant and intracellular HBV DNA increased with the proliferation of CD34+ HSCs. Similar results were obtained from intracellular HBsAg quantification tests. In addition, HBV DNA levels both in cells and in supernatants of CD34+ PBSCs increased proportionally, and the increments of HBV DNA in the supernatants paralleled those found in cells. CONCLUSIONS HBV can replicate in CD34+ HSCs in cord blood or peripheral blood of chronic HBV carriers.


Assuntos
Antígenos CD34/biossíntese , Sangue Fetal/virologia , Células-Tronco Hematopoéticas/virologia , Vírus da Hepatite B/fisiologia , Replicação Viral/fisiologia , Adulto , DNA Viral/sangue , Sangue Fetal/citologia , Células-Tronco Hematopoéticas/metabolismo , Células Hep G2 , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/genética , Vírus da Hepatite B/metabolismo , Humanos , Masculino
17.
Mol Med Rep ; 13(4): 3581-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26936285

RESUMO

Increasing evidence indicates that the hepatitis B virus (HBV) replicates in peripheral blood mononuclear cells (PBMCs), but at a low level. The present study aimed to establish a reliable and sensitive method that effectively detects HBV viral products for monitoring antiviral therapy, organ transplantation screening, and diagnosing occult HBV infection. In the present study, PBMCs (obtained from six healthy volunteers) were inoculated with HBV, and cultured with phytohemagglutinin (PHA) and interleukin­2 (IL­2) to stimulate cell proliferation. PBMCs were harvested, and quantitative detection of HBV DNA in cell suspension and intracellular hepatitis B surface antigen (HBsAg) was conducted on days 0, 1, 6 and 12, respectively. In situ hybridization, immunohistochemistry and reverse transcription­polymerase chain reaction (RT­PCR) were performed to analyze the HBV infection. The results demonstrated that HBV DNA increased concurrently with proliferation of PBMCs isolated from three of six healthy volunteers, and the mean number of PBMCs on day 12 was 13.61 times higher than the initially seeded cell number (P<0.01). The mean copies of HBV DNA at day 12 were 2.98 times higher compared with initial levels (P<0.05). Furthermore, intracellular HBsAg levels increased concurrently with proliferation of PBMCs in one group of cultured PBMCs, which was accompanied by increased HBV DNA levels. In addition, HBV nucleic acids were detected in PBMCs using in situ hybridization. Intracellular HBsAg was observed in PBMCs and HBV RNA was also detected by RT­PCR. The present study demonstrated that HBV replicates in proliferating PBMCs, which were induced by PHA and IL­2. This method offers a novel investigative tool to detect HBV infection in PBMCs and to monitor the course of HBV infection.


Assuntos
DNA Viral/análise , Vírus da Hepatite B/metabolismo , Adulto , Feminino , Antígenos de Superfície da Hepatite B/metabolismo , Humanos , Hibridização in Situ Fluorescente , Interleucina-2/farmacologia , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/virologia , Masculino , Microscopia de Fluorescência , Fito-Hemaglutininas/farmacologia , Reação em Cadeia da Polimerase em Tempo Real , Replicação Viral/efeitos dos fármacos , Adulto Jovem
18.
J Ethnopharmacol ; 184: 119-27, 2016 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-26952552

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Armillaria mellea (Vahl. ex. Fr.) Karst is an important traditional Chinese medicine used in dispelling wind and removing obstruction in the meridians, and strengthening tendons and bones. Armillaria mellea has been recorded in the book Caobenshiyi which was written by ancestor for the function of suppressing hyderactive liver for calming endogenous wind medicine. The aim of this study is to investigate the cytotoxic activity for liver cell lines (normal and cancerous) of protoilludane sesquiterpene aryl esters from the mycelium of A. mellea. MATERIALS AND METHODS: A systemic fractionation of the mycelium extracts of A. mellea and relative activity mechanisms were studied. RESULTS: Two new protoilludane sesquiterpene aryl esters named 5'-methoxy-armillasin (1) and 5-hydroxyl-armillarivin (2) were isolated. In addition, eight known protoilludane sesquiterpene aryl esters armillaridin (3), armillartin (4), armillarin (5), melleolide B (6), armillarilin (7), armillasin (8), armillarigin (9) and melleolide (10) were also isolated from the mycelium of A. mellea. The relative configurations of the two new compounds were confirmed by NOESY spectra. Among ten protoilludane sesquiterpene aryl esters, compounds 2, 3, 4, 7, 8, 9 and 10 were active constituents with highly cytotoxic activity against HepG2 cells (4.95-37.65µg/mL). We reported here for the time, that compound 10 (melleolide) showed anti-tumor ability on hepatoma cell. The relative mechanism was assessed on HepG2 cells. CONCLUSIONS: Among all the ten protoilludane sesquiterpene aryl esters, melleolide (10) showed the best cytotoxic activity for HepG2 cells (4.95µg/mL) and lower activity for L02 cells (16.05µg/mL). Mechanism study showed that melleolide decreased the viability of the cancer cells with varying levels of cleaved-caspase 3, caspase 8, caspase 9, Bax and Ki67 expression. On the other hand, melleolide induced HepG2 cell cycle arrest at the G2/M phase.


Assuntos
Antineoplásicos/farmacologia , Armillaria , Sesquiterpenos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ésteres , Humanos , Estrutura Molecular , Micélio/química , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação
19.
Biochem Pharmacol ; 105: 66-79, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26850986

RESUMO

Psoriasis is a multifactorial skin disease that inconveniences many patients. Considering the side effects and drug resistance of the current therapy, it is urgent to discover more effective and safer anti-psoriatic drugs. In the present study, we screened over 250 traditional Chinese medicine compounds for their ability to inhibit the cell viability of cultured human HaCaT keratinocytes, a psoriasis-relevant in vitro model, and found that periplogenin was highly effective. Mechanistic studies revealed that apoptosis and autophagy were not induced by periplogenin in HaCaT cells. However, periplogenin caused PI to permeate into cells, increased lactate LDH release and rapidly increased the number of necrotic cells. Additionally, the typical characteristics of necrosis were observed in the periplogenin-treated HaCaT cells. Notably, the necroptosis inhibitor Nec-1 and NSA were able to rescue the cells from necrotic cell death, supporting that necroptosis was involved in periplogenin-induced cell death. Furthermore, the ROS levels were elevated in the periplogenin-treated cells, NAC (an antioxidant) and Nec-1 could inhibit the ROS levels, and NAC could attenuate necroptotic cell death, indicating that the periplogenin-induced necroptotic cell death was mediated by oxidative stress. More importantly, in the murine models of TPA-induced epidermal hyperplasia and IMQ-induced skin inflammation, topical administration of periplogenin ameliorated skin lesions and inflammation. In sum, our results indicate, for the first time, that periplogenin is a naturally occurring compound with potent anti-psoriatic effects in vitro and in vivo, making it a promising candidate for future drug research.


Assuntos
Aminoquinolinas/toxicidade , Digitoxigenina/análogos & derivados , Modelos Animais de Doenças , Estresse Oxidativo/fisiologia , Psoríase/metabolismo , Acetato de Tetradecanoilforbol/toxicidade , Animais , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Digitoxigenina/farmacologia , Digitoxigenina/uso terapêutico , Feminino , Humanos , Imiquimode , Camundongos , Camundongos Endogâmicos BALB C , Necrose/induzido quimicamente , Necrose/tratamento farmacológico , Necrose/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Psoríase/induzido quimicamente , Psoríase/tratamento farmacológico
20.
J Theor Biol ; 394: 102-108, 2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-26804644

RESUMO

A B-cell epitope is a group of residues on the surface of an antigen that stimulates humoral immune responses. Identifying B-cell epitopes is important for effective vaccine design. Predicting epitopes by experimental methods is expensive in terms of time, cost and effort; therefore, computational methods that have a low cost and high speed are widely used to predict B-cell epitopes. Recently, epitope prediction based on random peptide library screening has been viewed as a promising method. Some novel software and web-based servers have been proposed that have succeeded in some test cases. Herein, we propose a novel epitope prediction method based on amino acid pairs and patch analysis. The method first divides antigen surfaces into overlapping patches based on both radius (R) and number (N), then predict epitopes based on Amino Acid Pairs (AAPs) from mimotopes and the surface patch. The proposed method yields a mean sensitivity of 0.53, specificity of 0.77, ACC of 0.75 and F-measure of 0.45 for 39 test cases. Compared with mimotope-based methods, patch-based methods and two other prediction methods, the sensitivity of the new method offers a certain improvement. Our findings demonstrate that this proposed method was successful for patch and AAPs analysis and allowed for conformational B-cell epitope prediction.


Assuntos
Algoritmos , Mapeamento de Epitopos/métodos , Epitopos de Linfócito B/química , Epitopos de Linfócito B/metabolismo , Aminoácidos/química , Bases de Dados de Proteínas , Conformação Proteica
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA