RESUMEN
A docking study of a novel series of benzofuran derivatives with ERα was conducted. In this study, we report the synthesis of a novel series of benzofuran derivatives and evaluation of their anticancer activity in vitro against MCF-7 human breast cancer cells, as well as their potential toxicity to ER-independent MDA-MB-231 breast cancer cells, human renal epithelial HEK-293 cells, and human immortal keratinocytes (HaCaT cells) by using the MTT colorimetric assay. The screening results indicated that the target compounds exhibited anti-breast cancer activity. The target compound 2-benzoyl-3-methyl-6-[2-(morpholin-4-yl)ethoxy]benzofuran hydrochloride (4e) exhibited excellent activity against anti-oestrogen receptor-dependent breast cancer cells and low toxicity. The preliminary structure-activity relationships of the target benzofuran derivatives have been summarised. In conclusion, the novel benzofuran scaffold may be a promising lead for the development of potential oestrogen receptor inhibitors.
Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Benzofuranos/química , Benzofuranos/farmacología , Neoplasias de la Mama/patología , Diseño de Fármacos , Receptores de Estrógenos/metabolismo , Antineoplásicos/síntesis química , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Simulación del Acoplamiento Molecular , Análisis Espectral/métodos , Relación Estructura-ActividadRESUMEN
The epidermal growth factor receptors (EGFRs), in which overexpression (known as upregulation) or overactivity have been associated with a number of cancers, has become an attractive molecular target for the treatment of selective cancers. We report here the design and synthesis of a novel series of 4,5-dihydro-1H-thieno [2',3':2,3]thiepino[4,5-c]pyrazole-3-carboxamide derivatives and the screening for their inhibitory activity on the EGFR high-expressing human A549 cell line using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). A Docking simulation was performed to fit compound 6g and gifitinib into the EGFR to determine the probable binding models, and the binding sites and modes conformation of 6g and gifitinib were exactly similar, the two compounds were stabilized by hydrogen bond interactions with MET769. Combining with the biological activity evaluation, compound 6g demonstrated the most potent inhibitory activity (IC50 = 9.68 ± 1.95 µmol·Lâ»1 for A549). Conclusively, 4,5-dihydro-1H-thieno[2',3':2,3]thiepino[4,5-c]pyrazole-3-carboxamide derivatives as the EGFR tyrosine kinase inhibitors were discovered, and could be used as potential lead compounds against cancer cells.
Asunto(s)
Receptores ErbB/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Pirazoles/farmacología , Células A549 , Gefitinib , Células Hep G2 , Humanos , Concentración 50 Inhibidora , Simulación del Acoplamiento Molecular , Pirazoles/síntesis química , Pirazoles/química , Quinazolinas/química , Quinazolinas/farmacologíaRESUMEN
In the past decade, miRNA emerges as a vital player in orchestrating gene regulation and maintaining cellular homeostasis. It is well documented that miRNA influences a variety of biological events, including embryogenesis, cell fate decision, and cellular differentiation. Adipogenesis is an organized process of cellular differentiation by which pre-adipocytes differentiate towards mature adipocytes. It has been shown that adipogenesis is tightly modulated by a number of transcription factors such as PPARγ, KLF4, and C/EBPα. However, the molecular mechanisms underlying the missing link between miRNA and adipogenesis-related transcription factors remain elusive. In this study, we unveiled that miR-25, a member of miR-106b-25 cluster, was remarkably downregulated during 3T3-L1 adipogenesis. Restored expression of miR-25 significantly impaired 3T3-L1 adipogenesis and downregulated the expression of serial adipogenesis-related genes. Further experiments presented that ectopic expression of miR-25 did not affect cell proliferation and cell cycle progression. Finally, KLF4 and C/EBPα, two key regulators of adipocyte differentiation, were experimentally identified as bona fide targets for miR-25. These data indicate that miR-25 is a novel negative regulator of adipocyte differentiation and it suppressed 3T3-L1 adipogenesis by targeting KLF4 and C/EBPα, which provides novel insights into the molecular mechanism of miRNA-mediated cellular differentiation.
Asunto(s)
Adipogénesis , Proteínas Potenciadoras de Unión a CCAAT/genética , Factores de Transcripción de Tipo Kruppel/genética , MicroARNs/metabolismo , Células 3T3-L1 , Animales , Diferenciación Celular , Regulación de la Expresión Génica , Factor 4 Similar a Kruppel , Ratones , Regiones Promotoras GenéticasRESUMEN
Milk contains an array of proteins with useful bioactivities. Many milk proteins encompassing native or chemically modified casein, lactoferrin, alpha-lactalbumin, and beta-lactoglobulin demonstrated antiviral activities. Casein and alpha-lactalbumin gained anti-HIV activity after modification with 3-hydroxyphthalic anhydride. Many milk proteins inhibited HIV reverse transcriptase. Bovine glycolactin, angiogenin-1, lactogenin, casein, alpha-lactalbumin, beta-lactoglobulin, bovine lactoferrampin, and human lactoferrampin inhibited HIV-1 protease and integrase. Several mammalian lactoferrins prevented hepatitis C infection. Lactoferrin, methylated alpha-lactalbumin and methylated beta-lactoglobulin inhibited human cytomegalovirus. Chemically modified alpha-lactalbumin, beta-lactoglobulin and lysozyme, lactoferrin and lactoferricin, methylated alpha-lactalbumin, methylated and ethylated beta-lactoglobulins inhibited HSV. Chemically modified bovine beta-lactoglobulin had antihuman papillomavirus activity. Beta-lactoglobulin, lactoferrin, esterified beta-lactoglobulin, and esterified lactoferrindisplayed anti-avian influenza A (H5N1) activity. Lactoferrin inhibited respiratory syncytial virus, hepatitis B virus, adenovirus, poliovirus, hantavirus, sindbis virus, semliki forest virus, echovirus, and enterovirus. Milk mucin, apolactoferrin, Fe(3+)-lactoferrin, beta-lactoglobulin, human lactadherin, bovine IgG, and bovine kappa-casein demonstrated antihuman rotavirus activity.
Asunto(s)
Antivirales/farmacología , Virus/efectos de los fármacos , Proteína de Suero de Leche/farmacología , Animales , Humanos , Mamíferos , Replicación Viral/efectos de los fármacosRESUMEN
We first identified fluorescein, ketazolam, antrafenine, darifenacin, fosaprepitant, paliperidone, risperidone, pimozide, trovafloxacin, and levofloxacin as inhibitors of fatty acid binding protein 4 using molecular docking screening from FDA-approved drugs. Subsequently, the biochemical characterizations showed that levofloxacin directly inhibited FABP4 activity in both the in vitro ligand displacement assay and cell-based function assay. Furthermore, levofloxacin did not induce adipogenesis in adipocytes, which is the major adverse effect of FABP4 inhibitors.
Asunto(s)
Descubrimiento de Drogas , Proteínas de Unión a Ácidos Grasos/antagonistas & inhibidores , Proteínas de Unión a Ácidos Grasos/metabolismo , Simulación del Acoplamiento Molecular , Bibliotecas de Moléculas Pequeñas/metabolismo , Bibliotecas de Moléculas Pequeñas/farmacología , United States Food and Drug Administration , Aprobación de Drogas , Proteínas de Unión a Ácidos Grasos/química , Humanos , Ligandos , Enfermedades Metabólicas/tratamiento farmacológico , Conformación Proteica , Bibliotecas de Moléculas Pequeñas/uso terapéutico , Estados UnidosRESUMEN
The Krüppel like factor 6 (KLF6) gene encodes multiple protein isoforms derived from alternative mRNA splicing, most of which are intimately involved in hepatocarcinogenesis and tumor progression. Recent bioinformatics analysis shows that alternative mRNA splicing of the KLF6 gene produces around 16 alternatively spliced variants with divergent or even opposing functions. Intriguingly, the full-length KLF6 (KLF6-FL) is a tumor suppressor gene frequently inactivated in liver cancer, whereas KLF6 splice variant 1 (KLF6-SV1) is an oncogenic isoform with antagonistic function against KLF6-FL. Compelling evidence indicates that miRNA, the small endogenous non-coding RNA (ncRNA), acts as a vital player in modulating a variety of cellular biological processes through targeting different mRNA regions of protein-coding genes. To identify the potential miRNAs specifically targeting KLF6-FL, we utilized bioinformatics analysis in combination with the luciferase reporter assays and screened out two miRNAs, namely miR-210 and miR-1301, specifically targeted the tumor suppressive KLF6-FL rather than the oncogenic KLF6-SV1. Our in vitro experiments demonstrated that stable expression of KLF6-FL inhibited cell proliferation, migration and angiogenesis while overexpression of miR-1301 promoted cell migration and angiogenesis. Further experiments demonstrated that miR-1301 was highly expressed in liver cancer cell lines as well as clinical specimens and we also identified the potential methylation and histone acetylation for miR-1301 gene. To sum up, our findings unveiled a novel molecular mechanism that specific miRNAs promoted tumorigenesis by targeting the tumor suppressive isoform KLF6-FL rather than its oncogenic isoform KLF6-SV1.
Asunto(s)
Carcinoma Hepatocelular/genética , Factores de Transcripción de Tipo Kruppel/metabolismo , Neoplasias Hepáticas/genética , MicroARNs/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Carcinoma Hepatocelular/metabolismo , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Células HEK293 , Células Hep G2 , Humanos , Factor 6 Similar a Kruppel , Factores de Transcripción de Tipo Kruppel/genética , Neoplasias Hepáticas/metabolismo , Metilación , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas Proto-Oncogénicas/genéticaRESUMEN
Marine organisms including bacteria, fungi, algae, sponges, echinoderms, mollusks, and cephalochordates produce a variety of products with antifungal activity including bacterial chitinases, lipopeptides, and lactones; fungal (-)-sclerotiorin and peptaibols, purpurides B and C, berkedrimane B and purpuride; algal gambieric acids A and B, phlorotannins; 3,5-dibromo-2-(3,5-dibromo-2-methoxyphenoxy)phenol, spongistatin 1, eurysterols A and B, nortetillapyrone, bromotyrosine alkaloids, bis-indole alkaloid, ageloxime B and (-)-ageloxime D, haliscosamine, hamigeran G, hippolachnin A from sponges; echinoderm triterpene glycosides and alkene sulfates; molluscan kahalalide F and a 1485-Da peptide with a sequence SRSELIVHQR; and cepalochordate chitotriosidase and a 5026.9-Da antifungal peptide. The antiviral compounds from marine organisms include bacterial polysaccharide and furan-2-yl acetate; fungal macrolide, purpurester A, purpurquinone B, isoindolone derivatives, alterporriol Q, tetrahydroaltersolanol C and asperterrestide A, algal diterpenes, xylogalactofucan, alginic acid, glycolipid sulfoquinovosyldiacylglycerol, sulfated polysaccharide p-KG03, meroditerpenoids, methyl ester derivative of vatomaric acid, lectins, polysaccharides, tannins, cnidarian zoanthoxanthin alkaloids, norditerpenoid and capilloquinol; crustacean antilipopolysaccharide factors, molluscan hemocyanin; echinoderm triterpenoid glycosides; tunicate didemnin B, tamandarins A and B and; tilapia hepcidin 1-5 (TH 1-5), seabream SauMx1, SauMx2, and SauMx3, and orange-spotted grouper ß-defensin. Although the mechanisms of antifungal and antiviral activities of only some of the aforementioned compounds have been elucidated, the possibility to use those known to have distinctly different mechanisms, good bioavailability, and minimal toxicity in combination therapy remains to be investigated. It is also worthwhile to test the marine antimicrobials for possible synergism with existing drugs. The prospects of employing them in clinical practice are promising in view of the wealth of these compounds from marine organisms. The compounds may also be used in agriculture and the food industry.
Asunto(s)
Antifúngicos/aislamiento & purificación , Antivirales/aislamiento & purificación , Organismos Acuáticos/química , Productos Biológicos/aislamiento & purificación , Antifúngicos/farmacología , Antivirales/farmacología , Productos Biológicos/farmacologíaRESUMEN
Although accumulating evidences indicate that miRNA emerge as a vital player in cell growth, development, and differentiation, how they contribute to the process of adipocyte differentiation remains elusive. In the present study, we revealed that the expression level of miR-210 was dramatically upregulated during 3T3-L1 adipogenesis. Ectopic introduction of miR-210 into 3T3-L1 cells promoted terminal differentiation as well as the expression of adipogenic markers. MTT assay showed that miR-210 significantly inhibited cell proliferation whereas the BrdU incorporation assay and flow cytometry analysis showed that miR-210 did not impair G1/S phase transition. Further experiments demonstrated that enhanced expression of miR-210 in 3T3-L1 cells provoked adipocyte differentiation via activation of PI3K/Akt pathway by targeting SHIP1, a negative regulator of PI3K/Akt pathway. Moreover, blockade of endogenous miR-210 during adipogenesis significantly repressed adipocyte differentiation. In summary, we have identified miR-210 as an important positive regulator in adipocyte differentiation through the activation of PI3K/Akt pathway.
Asunto(s)
Adipogénesis/genética , Diferenciación Celular/genética , MicroARNs/genética , Células 3T3-L1 , Adipocitos/metabolismo , Animales , Proliferación Celular , Ratones , Proteína Oncogénica v-akt/genética , Proteína Oncogénica v-akt/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , FosforilaciónRESUMEN
The global morbidity of obesity and type 2 diabetes mellitus (T2DM) has dramatically increased. Insulin resistance is the most important pathogenesis and therapeutic target of T2DM. The traditional Chinese medicine formula Astragalus mongholicus powder (APF), consists of Astragalus mongholicus Bunge [Fabaceae], Pueraria montana (Lour.) Merr. [Fabaceae], and Morus alba L. [Moraceae] has a long history to be used to treat diabetes in ancient China. This work aims to investigate the effects of APF on diabetic mice and its underlying mechanism. Diabetic mice were induced by High-fat-diet (HFD) and streptozotocin (STZ). The body weight of mice and their plasma levels of glucose, insulin, leptin and lipids were examined. Reverse transcription-polymerase chain reaction, histology, and Western blot analysis were performed to validate the effects of APF on diabetic mice and investigate the underlying mechanism. APF reduced hyperglycemia, hyperinsulinemia, and hyerleptinemia and attenuate the progression of obesity and non-alcoholic fatty liver disease (NAFLD). However, these effects disappeared in leptin deficient ob/ob diabetic mice and STZ-induced insulin deficient type 1 diabetic mice. Destruction of either these hormones would abolish the therapeutic effects of APF. In addition, APF inhibited the protein expression of PTP1B suppressing insulin-leptin sensitivity, the gluconeogenic gene PEPCK, and the adipogenic gene FAS. Therefore, insulin-leptin sensitivity was normalized, and the gluconeogenic and adipogenic genes were suppressed. In conclusion, APF attenuated obesity, NAFLD, and T2DM by regulating the balance of adipoinsular axis in STZ + HFD induced T2DM mice.
RESUMEN
Alzheimer's disease (AD) is a common form of dementia which is characterized by the deposition of amyloids in affected neurons and a cholinergic neurotransmission deficit in the brain. The current therapeutic intervention for AD is primarily based on the inhibition of brain acetylcholinesterase (AChE) to restore the brain acetylcholine level. Cryptotanshinone (CT) is a diterpene extracted from the root of Salvia miltiorrhiza, a herb that is commonly prescribed in Chinese medicine to treat cardiovascular disease. In the present study, we demonstrated that CT is an inhibitor of both human acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) with IC(50) values of 4.09 and 6.38 microM, respectively. The IC(50) ratio of CT for BuChE:AChE was 1.56. CT inhibited human AChE in a reversible manner, and the inhibition showed the characteristics of mixed-type as both the KM and V(max) were affected by CT. The effect of CT on learning impairment in scopolamine-treated rats was also evaluated by the acquisition protocol of the Morris water maze. The task learning ability of scopolamine-treated rats was significantly reversed by CT (5 mg/kg), and the CT-fed rats were able to develop a spatial searching strategy comparable to that of the control animals. In addition, chronic CT treatment did not cause hepatotoxicity as measured by blood alanine transferase (ALT) level. Our findings demonstrate the ability of CT to improve task learning in rats with scopolamine-induced cognitive impairment. These results suggest that CT has the potential as a therapeutic drug for treating AD.
Asunto(s)
Amnesia/tratamiento farmacológico , Inhibidores de la Colinesterasa/uso terapéutico , Aprendizaje por Laberinto/efectos de los fármacos , Fenantrenos/uso terapéutico , Fitoterapia , Extractos Vegetales/uso terapéutico , Salvia miltiorrhiza/química , Acetilcolinesterasa/metabolismo , Enfermedad de Alzheimer/tratamiento farmacológico , Amnesia/inducido químicamente , Amnesia/metabolismo , Animales , Butirilcolinesterasa/metabolismo , Inhibidores de la Colinesterasa/aislamiento & purificación , Inhibidores de la Colinesterasa/farmacología , Humanos , Masculino , Fenantrenos/aislamiento & purificación , Fenantrenos/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Raíces de Plantas , Ratas , Ratas Sprague-Dawley , EscopolaminaRESUMEN
BACKGROUND: Severe acute respiratory syndrome (SARS) is a life-threatening form of pneumonia caused by SARS coronavirus (SARS-CoV). From late 2002 to mid 2003, it infected more than 8000 people worldwide, of which a majority of cases were found in China. Owing to the absence of definitive therapeutic Western medicines, Houttuynia cordata Thunb. (Saururaceae)(HC) was shortlisted by Chinese scientists to tackle SARS problem as it is conventionally used to treat pneumonia. AIM OF THE STUDY: The present study aimed to explore the SARS-preventing mechanisms of HC in the immunological and anti-viral aspects. RESULTS: Results showed that HC water extract could stimulate the proliferation of mouse splenic lymphocytes significantly and dose-dependently. By flow cytometry, it was revealed that HC increased the proportion of CD4(+) and CD8(+) T cells. Moreover, it caused a significant increase in the secretion of IL-2 and IL-10 by mouse splenic lymphocytes. In the anti-viral aspect, HC exhibited significant inhibitory effects on SARS-CoV 3C-like protease (3CL(pro)) and RNA-dependent RNA polymerase (RdRp). On the other hand, oral acute toxicity test demonstrated that HC was non-toxic to laboratory animals following oral administration at 16 g/kg. CONCLUSION: The results of this study provided scientific data to support the efficient and safe use of HC to combat SARS.
Asunto(s)
Antivirales/administración & dosificación , Medicamentos Herbarios Chinos/administración & dosificación , Síndrome Respiratorio Agudo Grave/tratamiento farmacológico , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/efectos de los fármacos , Administración Oral , Animales , Antivirales/aislamiento & purificación , Antivirales/toxicidad , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/metabolismo , Proliferación Celular/efectos de los fármacos , China , Relación Dosis-Respuesta a Droga , Medicamentos Herbarios Chinos/toxicidad , Femenino , Citometría de Flujo , Houttuynia , Ratones , Ratones Endogámicos BALB C , Bazo/citología , Pruebas de Toxicidad AgudaRESUMEN
Chemokine receptor CXCR4 was involved in the progression of breast cancer to a metastatic phenotype, leading to the major cause of death in patients. A more in-depth understanding of signaling mechanism underlying CXCR4 is critical to develop effective therapies toward metastasis. Recently, the role of antimicrobial peptide LL-37 in contributing to the metastasis of breast cancer cells was observed. Clinical analysis of data herein demonstrated for the first time that overexpression of LL-37 and CXCR4 co-existed in human primary breast tumors with lymph node metastases. Further study disclosed that forced expression of CXCR4 led to the enhancement of pro-migratory signaling and migration rate induced by LL-37 in breast cancer cells. Moreover, LL-37 affected tumor microenvironment including induction of migration of mesenchymal stem cells and CXCR4-dependent capillary-like tubule formation. Functional analysis showed that LL-37 induced the internalization of CXCR4 through approaching Glu268, the residue of CXCR4, independent of the binding pocket (Asp171, Asp262, and Glu288) for CXCR4 inhibitor AMD3100, signifying that LL-37 is a distinct agonist of CXCR4. These results suggest the reciprocal roles of LL-37 and CXCR4 in promoting breast cancer cell migration and provide new insight into the design of CXCR4 inhibitor for intervention of metastatic breast cancer.
Asunto(s)
Neoplasias de la Mama/patología , Catelicidinas/metabolismo , Movimiento Celular , Receptores CXCR4/metabolismo , Adulto , Anciano , Péptidos Catiónicos Antimicrobianos , Bencilaminas , Sitios de Unión , Mama/patología , Catelicidinas/química , Línea Celular Tumoral , Proliferación Celular , Ciclamas , Femenino , Regulación Neoplásica de la Expresión Génica , Compuestos Heterocíclicos/química , Compuestos Heterocíclicos/farmacología , Humanos , Metástasis Linfática , Células Madre Mesenquimatosas , Persona de Mediana Edad , Simulación del Acoplamiento Molecular , Unión Proteica/efectos de los fármacos , Receptores CXCR4/agonistas , Receptores CXCR4/antagonistas & inhibidores , Receptores CXCR4/química , Transducción de Señal , Microambiente Tumoral , Regulación hacia ArribaRESUMEN
Currently, many strains of influenza A virus have developed resistance against anti-influenza drugs, and it is essential to find new chemicals to combat this virus. The influenza polymerase with three proteins, PA, PB1 and PB2, is a crucial component of the viral ribonucleoprotein (RNP) complex. Here, we report the identification of a hit compound 221 by surface plasmon resonance (SPR) direct binding screening on the C-terminal of PA (PAC). Compound 221 can subdue influenza RNP activities and attenuate influenza virus replication. Its analogs were subsequently investigated and twelve of them could attenuate RNP activities. One of the analogs, compound 312, impeded influenza A virus replication in Madin-Darby canine kidney cells with IC50 of 27.0 ± 16.8 µM. In vitro interaction assays showed that compound 312 bound directly to PAC with Kd of about 40 µM. Overall, the identification of novel PAC-targeting compounds provides new ground for drug design against influenza virus in the future.
Asunto(s)
Antivirales/aislamiento & purificación , Antivirales/farmacología , Evaluación Preclínica de Medicamentos/métodos , Virus de la Influenza A/enzimología , ARN Polimerasa Dependiente del ARN/antagonistas & inhibidores , Resonancia por Plasmón de Superficie , Proteínas Virales/antagonistas & inhibidores , Animales , ARN Polimerasas Dirigidas por ADN/análisis , Perros , Virus de la Influenza A/efectos de los fármacos , Virus de la Influenza A/fisiología , Concentración 50 Inhibidora , Células de Riñón Canino Madin Darby , Unión Proteica , Replicación Viral/efectos de los fármacosRESUMEN
RNA interference (RNAi) has become one of the most powerful and popular approach on gene silencing in clinical research study especially in virology due to the gene-specific suppression property of small interfering RNA (siRNA). In this report, we demonstrate that expression of vector-mediated small hairpin RNA (shRNA) against human immunodeficiency virus type 1 (HIV-1) integrase (IN), one of the three important enzymes in HIV infection by controlling the integration of viral RNA to host DNA, could suppress the protein synthesis of EGFP-tagged IN in HeLa cell model efficiently. Furthermore, we show that IN shRNA can successfully reduce the HIV particles production in 293T cells at the level similar to the positive control of HIV-1 tat shRNA. These results provide the therapeutic possibility of HIV replication using RNAi against HIV-1 integrase.
Asunto(s)
Integrasa de VIH , VIH-1/efectos de los fármacos , Interferencia de ARN , ARN Interferente Pequeño/farmacología , Replicación Viral/efectos de los fármacos , Células Cultivadas , Regulación Viral de la Expresión Génica , Productos del Gen gag/metabolismo , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Integrasa de VIH/genética , Integrasa de VIH/metabolismo , Inhibidores de Integrasa VIH/farmacología , VIH-1/genética , VIH-1/fisiología , Células HeLa , Humanos , Datos de Secuencia Molecular , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , TransfecciónRESUMEN
A novel orange fluorescent protein (OFP) was cloned from the tentacles of Cnidarian tube anemone Cerianthus sp. It consists of 222 amino acid residues with a calculated molecular mass of 25.1 kDa. A BLAST protein sequence homology search revealed that native OFP has 81% sequence identity to Cerianthus membranaceus green fluorescent protein (cmFP512), 38% identity to Entacmaea quadricolor red fluorescent protein (eqFP611), 37% identity to Discosoma red fluorescent protein (DsRed), 36% identity to Fungia concinna Kusabira-orange fluorescent protein (KO), and a mere 21% identity to green fluorescent protein (GFP). It is most likely that OFP also adopts the 11-strand beta-barrel structure of fluorescent proteins. Spectroscopic analysis indicated that it has a wide absorption spectrum peak at 548 nm with two shoulders at 487 and 513 nm. A bright orange fluorescence maximum at 573 nm was observed when OFP was excited at 515 nm or above. When OFP was excited well below 515 nm, a considerable amount of green emission maximum at 513 nm was also observed. It has a fluorescence quantum yield (Phi) of 0.64 at 25 degrees C. The molar absorption coefficients (epsilon) of folded OFP at 278 and 548 nm are 47,000 and 60,000 M(-1) x cm(-1), respectively. Its fluorescent brightness (epsilon Phi) at 25 degrees C is 38,400 M(-1) x cm(-1). Like other orange-red fluorescent proteins, OFP is also tetrameric. It was readily expressed as soluble protein in Escherichia coli at 37 degrees C, and no aggregate was observed in transfected HeLa cells under our experimental conditions. Fluorescent intensity of OFP is detectable over a pH range of 3 to 12.
Asunto(s)
Antozoos/genética , Proteínas Luminiscentes/biosíntesis , Proteínas Luminiscentes/genética , Proteínas Recombinantes/biosíntesis , Secuencia de Aminoácidos , Animales , Clonación Molecular , Cartilla de ADN/química , Electroforesis en Gel de Poliacrilamida , Escherichia coli/genética , Células HeLa , Humanos , Concentración de Iones de Hidrógeno , Proteínas Luminiscentes/química , Datos de Secuencia Molecular , Estructura Cuaternaria de Proteína , Proteínas Recombinantes/química , Alineación de SecuenciaRESUMEN
Influenza A virus is the major cause of epidemics and pandemics worldwide. In this study, virtual screening was used to identify compounds interacting with influenza A polymerase PB2 cap-binding domain (CBD). With a database of 21,351 small molecules, 28 candidate compounds were tested and one compound (225) was identified as hit compound. Compound 225 and three of its analogs (225D1, 426 and 426Br) were found to bind directly to PB2 CBD by surface plasmon resonance (SPR). The evaluation of compounds 426Br and 225 indicated that they could bind to PB2 CBD and inhibit influenza virus at low micromolar concentration. They were predicted to bind the cap binding site of the protein by molecular modeling and were confirmed by SPR assay using PB2 CBD mutants. These two compounds have novel scaffolds and could be further developed into lead compound for influenza virus inhibition.
Asunto(s)
Antivirales/aislamiento & purificación , Evaluación Preclínica de Medicamentos , Inhibidores Enzimáticos/aislamiento & purificación , Virus de la Influenza A/enzimología , Proteínas Virales/antagonistas & inhibidores , Animales , Antivirales/química , Perros , Inhibidores Enzimáticos/química , Células HEK293 , Humanos , Células de Riñón Canino Madin Darby , Pruebas de Sensibilidad Microbiana , Unión Proteica , Resonancia por Plasmón de SuperficieRESUMEN
A novel neuroendocrine peptide, pituitary adenylate cyclase activating peptide (PACAP), was found to have an important role in carbohydrate or lipid metabolism and was susceptible to dipeptidyl peptidase IV degradation. It can not only mediate glucose-dependent insulin secretion and lower blood glucose by activating VPAC2 receptor, but also raise blood glucose by promoting glucagon production by VPAC1 receptor activation. Therefore, its therapeutic application is restricted by the exceedingly short-acting half-life and the stimulatory function for glycogenolysis. Herein, we generated novel peptide-conjugated selenium nanoparticles (SeNPs; named as SCD), comprising a 32-amino acid PACAP-derived peptide DBAYL that selectively binds to VPAC2, and chitosan-modified SeNPs (SeNPs-CTS, SC) as slow-release carrier. The circulating half-life of SCD is 14.12 h in mice, which is 168.4-and 7.1-fold longer than wild PACAP (~5 min) and DBAYL (~1.98 h), respectively. SCD (10 nmol/L) significantly promotes INS-1 cell proliferation, glucose uptake, insulin secretion, insulin receptor expression and also obviously reduces intracellular reactive oxygen species levels in H2O2-injured INS-1 cells. Furthermore, the biological effects of SCD are stronger than Exendin-4 (a clinically approved drug through its insulinotropic effect), DBAYL, SeNPs or SC. A single injection of SCD (20 nmol/kg) into db/db mice with type 2 diabetes leads to enhanced insulin secretion and sustained hypoglycemic effect, and the effectiveness and duration of SCD in enhancing insulin secretion and reducing blood glucose levels are much stronger than Exendin-4, SeNPs or SC. In db/db mice, chronic administration of SCD by daily injection for 12 weeks markedly improved glucose and lipid profiles, insulin sensitivity and the structures of pancreatic and adipose tissue. The results indicate that SC can play a role as a carrier for the slow release of bioactive peptides and SCD could be a hopeful therapeutic against type 2 diabetes through the synergy effects of DBAYL and SeNPs.
Asunto(s)
Quitosano/química , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Nanopartículas/química , Péptidos/uso terapéutico , Receptores de Tipo II del Péptido Intestinal Vasoactivo/agonistas , Selenio/química , Animales , Glucemia/metabolismo , Proliferación Celular/efectos de los fármacos , Diabetes Mellitus Tipo 2/patología , Liberación de Fármacos , Exenatida , Ayuno/sangre , Glucosa/metabolismo , Glucosa/farmacología , Semivida , Peróxido de Hidrógeno/toxicidad , Insulina/genética , Insulina/metabolismo , Resistencia a la Insulina , Masculino , Ratones , Péptidos/farmacología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Receptor de Insulina/metabolismo , Ponzoñas/uso terapéuticoRESUMEN
BACKGROUND: Traditionally, molecular docking is primarily employed to screen pure compounds; the top-ranking chemicals are subsequently selected for experimental validation. Unlike synthetic chemicals, most natural products are commercially unavailable. The isolation and purification of each natural product is extremely time-consuming, which has restricted the screening of lead compounds from natural products. PURPOSE: We developed a protocol, Herbalog, to facilitate the identification of bioactive phytochemicals through molecular docking. METHODS: We wrote a script using Python and Autodock Vina for docking; ligand displacement and adipolysis assays were used to determine the anti-fatty acid binding protein (FABP) 4 activity of bioactive extracts. An ultraperformance liquid chromatography quadrupole time-of-flight mass spectrometry system was applied for identifying major peaks of bioactive extracts. RESULTS: Herbalog, a natural product database, contains 5,112 phytochemicals from 197 common herbs and a script that counts the number of hits from docking in each herb and calculates the hit rate of herbs. Herbalog prioritizes herbs according to their hit rates, and top-ranking herb candidates contain a large repertoire of hits. We used Herbalog as a screening tool and identified labdane diterpenoids from Andrographis paniculata as leading candidates of FABP4 inhibitors. CONCLUSION: Herbalog facilitates the discovery of herbs that possess the highest number of inhibitors or activators against target proteins, which reduces the sample preparation time for preliminary validation.
Asunto(s)
Andrographis/química , Diterpenos/farmacología , Descubrimiento de Drogas/métodos , Proteínas de Unión a Ácidos Grasos/antagonistas & inhibidores , Medicina de Hierbas/métodos , Simulación del Acoplamiento Molecular/métodos , Extractos Vegetales/farmacología , Cromatografía Liquida , Bases de Datos Factuales , Medicamentos Herbarios Chinos/farmacología , Humanos , Espectrometría de Masas , Plantas Medicinales/químicaRESUMEN
This study aimed to investigate fragments derived from human and bovine lactoferrins for ability to inhibit nuclear translocation of HIV-1 integrase. It was shown that human lactoferricin, human lactoferrin 1-11, and bovine lactoferrampin reduced nuclear distribution of HIV-1 integrase. Bovine lactoferrampin could inhibit both the activity and nuclear translocation of HIV-1 integrase. Human lactoferrampin, bovine lactoferricin, and bovine lactoferrin 1-11 had no effect on HIV-1 integrase nuclear translocation. Human lactoferrampin which inhibited the activity of integrase did not prevent its nuclear translocation. Human lactoferricin and lactoferrin 1-11 did not inhibit HIV-1 integrase nuclear translocation despite their ability to attenuate the enzyme activity. The discrepancy between the findings on reduction of HIV-1 activity and inhibition of nuclear translocation of HIV-1 integrase was due to the different mechanisms involved. A similar reasoning can also be applied to the different inhibitory potencies of the milk peptides on different HIV enzymes, i.e., nuclear translocation.
Asunto(s)
Integrasa de VIH/metabolismo , VIH-1/efectos de los fármacos , Lactoferrina/genética , Fragmentos de Péptidos/genética , Animales , Bovinos , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Integrasa de VIH/genética , Inhibidores de Integrasa VIH/farmacología , VIH-1/patogenicidad , Humanos , Lactoferrina/farmacología , Fragmentos de Péptidos/farmacología , Transporte de Proteínas/efectos de los fármacosRESUMEN
Recently, the long non-coding RNA (lncRNA) H19 has been identified as an oncogenic gene in multiple cancer types and elevated expression of H19 was tightly linked to tumorigenesis and cancer progression. However, the molecular basis for this observation has not been characterized in colorectal cancer (CRC) especially during epithelial to mesenchymal transition (EMT) progression. In our studies, H19 was characterized as a novel regulator of EMT in CRC. We found that H19 was highly expressed in mesenchymal-like cancer cells and primary CRC tissues. Stable expression of H19 significantly promotes EMT progression and accelerates in vivo and in vitro tumor growth. Furthermore, by using bioinformatics study and RNA immunoprecipitation combined with luciferase reporter assays, we demonstrated that H19 functioned as a competing endogenous RNA (ceRNA) for miR-138 and miR-200a, antagonized their functions and led to the de-repression of their endogenous targets Vimentin, ZEB1, and ZEB2, all of which were core marker genes for mesenchymal cells. Taken together, these observations imply that the lncRNA H19 modulated the expression of multiple genes involved in EMT by acting as a competing endogenous RNA, which may build up the missing link between the regulatory miRNA network and EMT progression.