RESUMO
Compound 1 (ent-16-oxobeyeran-19-N-methylureido) is a semisynthetic isosteviol derivative that shows anti-hepatitis B virus activity in Huh7 cells by affecting viral DNA transcription and the Toll-like receptor 2/nuclear factor-κB signaling pathway. Thus, the pharmacokinetics and metabolite identification were studied as part of the discovery and development process of compound 1. The pharmacokinetics was evaluated after administration to rats at an intravenous dose of 2 mg/kg, and oral doses of 2, 5 and 10 mg/kg. Plasma concentrations were determined using LC-MS/MS. Moreover, urine samples from rats dosed at 10 mg/kg were scanned for metabolites using UPLC-QTOF-MS/MS. Results for the intravenously administered dose of 2 mg/kg showed that the area under the concentration-time curve was 65,223.31 ± 4269.80 ng min/mL, and the systemic clearance was 0.031 ± 0.0021 L/min. Oral pharmacokinetic parameters were dose-dependent, showing nonproportional increases in the oral AUCs with respective values of 4371.62 ± 3084.81, 22,472.75 ± 9103.33 and 135,141.83 ± 38,934.03 ng min/mL for 2, 5 and 10 mg/kg. The bioavailability was low at 1.5% for 2 mg/kg dose, and at 1.1% for both 5 and 10 mg/kg doses. Metabolites excreted in the urine indicate possible N-oxidation and glucuronide conjugation.
RESUMO
ent-13-Hydroxykaur-16-ene-19-N-butylureide (6) was one of 33 synthesized C-4-substituted steviol derivatives that were evaluated for their effects on hepatitis B virus (HBV) surface antigen (HBsAg) secretion. The IC50 (16.9 µM) and SI (57.7) values for inhibiting HBV DNA replication of compound 6 were greater than those of the reference compound, lamivudine (3-TC; IC50: 107.5 µM; SI: 22.0). Thus, the anti-HBV mechanism of 6 was investigated, and it specifically inhibited viral gene expression and reduced viral DNA levels, as well as potently attenuated all of the viral promoter activity of HBV-expressing Huh7 cells. Examination of cellular signaling pathways found that 6 inhibited the activities of the nuclear factor (NF)-κB- and activator protein (AP)-1 element-containing promoters, but had no effects on AP-2 or interferon-stimulated response element (ISRE)-containing promoters in HBV-expressing cells. Meanwhile, it significantly eliminated NF-κB and extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinase (MAPK) signaling-related protein levels and inhibited their phosphorylation in HBV-transfected Huh7 cells. The inhibitory potency of 6 against HBV DNA replication was reversed by cotransfecting the NF-κB p65 expression plasmid. Using the MAPK-specific activator anisomycin also reversed the inhibitory effect of 6 on viral DNA replication. The present findings suggest that the anti-HBV mechanism of 6 is partly mediated through the NF-κB and MAPK signaling pathways.
Assuntos
Diterpenos do Tipo Caurano/síntese química , Diterpenos do Tipo Caurano/farmacologia , Vírus da Hepatite B/efeitos dos fármacos , Replicação do DNA/efeitos dos fármacos , DNA Viral/efeitos dos fármacos , Diterpenos do Tipo Caurano/classificação , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Estrutura Molecular , NF-kappa B/metabolismo , Fosforilação/efeitos dos fármacos , Fator de Transcrição AP-1/metabolismo , Replicação Viral/efeitos dos fármacosRESUMO
A series of novel isosteviol derivatives having C4-amide substituents were synthesized in order to test for antiviral effects against the hepatitis B virus (HBV) in vitro. Among them, IN-4 [N-(propylcarbonyl)-4α-amino-19-nor-ent-16-ketobeyeran] (5) exhibited inhibitory activity against secretion of HBsAg and HBeAg as well as inhibition of HBV DNA replication. Therefore, the mechanism of its antiviral activity was further analyzed using HBV-transfected Huh7 cells. Exposure to IN-4 produced minimal inhibitory effects on viral precore/pregenomic RNA expression. However, expression levels of the 2.4/2.1-kb preS/major S RNA of the viral surface gene significantly decreased, along with intracellular levels of HBV DNA. A promoter activity analysis demonstrated that IN-4 significantly inhibited viral X, S, and preS expression levels but not viral core promoter activities. In particular, IN-4 was observed to significantly inhibit HBV gene regulation by disrupting nuclear factor (NF)-κB-associated promoter activity. In addition, the nuclear expression of p65/p50 NF-κB member proteins was attenuated following IN-4 treatment, while cytoplasmic IκBα protein levels were enhanced. Meanwhile, IN-4 was observed to inhibit the binding activity of NF-κB to putative DNA elements. Furthermore, transfection of a p65 expression plasmid into Huh7 cells significantly reversed the inhibitory effect of IN-4 on HBV DNA levels, providing further evidence of the central role of NF-κB in its antiviral mechanism. It is therefore suggested that IN-4 inhibits HBV by interfering with the NF-κB signaling pathway, resulting in downregulation of viral gene expression and DNA replication.
Assuntos
Antivirais/química , Antivirais/farmacologia , Diterpenos do Tipo Caurano/química , Diterpenos do Tipo Caurano/farmacologia , Vírus da Hepatite B/efeitos dos fármacos , Amidas/síntese química , Amidas/química , Amidas/farmacologia , Antivirais/síntese química , Linhagem Celular , Replicação do DNA/efeitos dos fármacos , DNA Viral/genética , Diterpenos do Tipo Caurano/síntese química , Hepatite B/tratamento farmacológico , Hepatite B/metabolismo , Hepatite B/virologia , Antígenos de Superfície da Hepatite B/metabolismo , Antígenos E da Hepatite B/metabolismo , Vírus da Hepatite B/genética , Vírus da Hepatite B/metabolismo , Humanos , NF-kappa B/metabolismoRESUMO
Seven new oleanane-type triterpenoids (1-7), named fatsicarpains A-G, and the known compounds 3α-hydroxyolean-11,13(18)-dien-28-oic acid (8) and 3α-hydroxyolean-11-en-28,13ß-olide (9) were isolated from the leaves and twigs of Fatsia polycarpa on the basis of bioassay-guided fractionation. The structures of compounds 1-7 were elucidated through spectroscopic analyses and single-crystal X-ray crystallography of 1, 8, and 9. Cytotoxicity against HepG2 2.2.15 and AGS cells and antihepatitis B virus (HBV) and antibacterial activities of 1-9 were also evaluated in vitro.
Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Araliaceae/química , Ácido Oleanólico/análogos & derivados , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Vírus da Hepatite B/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Ácido Oleanólico/química , Ácido Oleanólico/isolamento & purificação , Ácido Oleanólico/farmacologia , Folhas de Planta/química , Caules de Planta/químicaRESUMO
ent-16-Oxobeyeran-19-N-methylureido (NC-8) is a recently synthesized derivative of isosteviol that showed anti-hepatitis B virus (HBV) activity by disturbing replication and gene expression of the HBV and by inhibiting the host toll-like receptor 2/nuclear factor-κB signaling pathway. To study its pharmacokinetics as a part of the drug development process, a highly sensitive, rapid, and reliable liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed and validated for determining NC-8 in rat plasma. After protein precipitation extraction, the chromatographic separation of the analyte and internal standard (IS; diclofenac sodium) was performed on a reverse-phase Luna C18 column coupled with a Quattro Ultima triple quadruple mass spectrometer in the multiple-reaction monitoring mode using the transitions, m/z 347.31 â 75.09 for NC-8 and m/z 295.89 â 214.06 for the IS. The lower limit of quantitation was 0.5 ng/mL. The linear scope of the standard curve was between 0.5 and 500 ng/mL. Both the precision (coefficient of variation; %) and accuracy (relative error; %) were within acceptable criteria of <15%. Recoveries ranged from 104% to 113.4%, and the matrix effects (absolute) were non-significant (CV ≤ 6%). The validated method was successfully applied to investigate the pharmacokinetics of NC-8 in male Sprague-Dawley rats. The present methodology provides an analytical means to better understand the preliminary pharmacokinetics of NC-8 for investigations on further drug development.
Assuntos
Antivirais/farmacocinética , Cromatografia Líquida , Diterpenos do Tipo Caurano/farmacocinética , Espectrometria de Massas em Tandem , Animais , Antivirais/química , Diterpenos do Tipo Caurano/química , Estabilidade de Medicamentos , Vírus da Hepatite B/efeitos dos fármacos , Estrutura Molecular , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos TestesRESUMO
NC-8 (ent-16-oxobeyeran-19-N-methylureido) is an isosteviol-derived analogue with multiple biological effects, including anti-inflammation and anti-bacterial activities and inhibition of HBV viral surface antigen gene expression. In this study, we explored the effects of NC-8 on the formation of osteoclasts from RAW 264.7 cells. We found that NC-8 exerts the novel effect of inhibiting osteoclast-like cell formation. Our experiments showed that RANKL-induced ERK, p38, and JNK phosphorylation were inhibited by NC-8. An ovariectomy-induced osteoporosis animal model was used to examine the protective effects of oral treatment with NC-8. Serum analysis was used to examine markers of osteoblasts, osteoclasts, and renal and hepatic function in rats. Micro CT scanning and histological analysis were used to measure bone loss in ovariectomized rats. Oral administration of NC-8 effectively decreased excess bone resorption and significantly antagonized trabecular bone loss in ovariectomized rats. Serum analysis of C-terminal telopeptide of type-I collagen, an osteoclast marker, also showed that NC-8 administration inhibited excess bone resorption. Furthermore, serum analysis showed that renal and liver function were not affected by these doses of NC-8 during long-term treatment. Our results demonstrate that NC-8 inhibits osteoclast differentiation and effectively ameliorates ovariectomy-induced osteoporosis.
Assuntos
Reabsorção Óssea/tratamento farmacológico , Diterpenos do Tipo Caurano/administração & dosagem , Osteoclastos/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Animais , Reabsorção Óssea/sangue , Reabsorção Óssea/genética , Reabsorção Óssea/patologia , Diferenciação Celular/efeitos dos fármacos , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , MAP Quinase Quinase 4/genética , Sistema de Sinalização das MAP Quinases/genética , Camundongos , Osteoblastos/efeitos dos fármacos , Osteoclastos/metabolismo , Osteoporose/sangue , Osteoporose/genética , Osteoporose/patologia , Ovariectomia/efeitos adversos , Fosforilação/efeitos dos fármacos , Células RAW 264.7 , Ratos , Proteínas Quinases p38 Ativadas por Mitógeno/genéticaRESUMO
BACKGROUND: The Campylobacter species usually causes infection between humans and livestock interaction via livestock breeding. The studies of the Campylobacter species thus far in all clinical isolates were to show the many kinds of antibiotic phenomenon that were produced. Their integrons cause the induction of antibiotic resistance between bacterial species in the Campylobacter species. RESULTS: The bacterial strains from the diarrhea of pediatric patient which isolated by China Medical University Hospital storage bank. These isolates were identified by MALDI-TOF mass spectrometry. The anti-microbial susceptibility test showed that Campylobacter species resistant to cefepime, streptomycin, tobramycin and trimethoprim/sulfamethoxazole (all C. jejuni and C. coli isolates), ampicillin (89% of C. jejuni; 75% of C. coli), cefotaxime (78% of C. jejuni; 100% of C. coli), nalidixic acid (78% of C. jejuni; 100% of C. coli), tetracycline (89% of C. jejuni; 25% C. coli), ciprofloxacin (67% of C. jejuni; 50% C. coli), kanamycin (33% of C. jejuni; 75% C. coli) and the C. fetus isolate resisted to ampicillin, cefotaxime, nalidixic acid, tetracycline, ciprofloxacin, kanamycin by disc-diffusion method. The effect for ciprofloxacin and tetracycline of the Campylobacter species was tested using an E-test. The tet, erm, and integron genes were detected by PCR assay. According to the sequencing analysis (type I: dfr12-gcuF-aadA2 genes and type II: dfrA7 gene), the cassette type was identified. The most common gene cassette type (type I: 9 C. jejuni and 2 C. coli isolates; type II: 1 C. coli isolates) was found in 12 class I integrase-positive isolates. CONCLUSIONS: Our results suggested an important information in the latency of Campylobacter species with resistance genes, and irrational antimicrobial use should be concerned.
RESUMO
In the present study, the complete mitogenome sequence of the Cyprinid fish Squalidus argentatus (Cypriniformes, Cyprinidae) was determined. The mitogenome, consisting of 16,609 base pairs (bp), was characterized by the typical vertebrate mitochondrial gene arrangement, including 13 protein-coding, 22 transfer RNAs, 2 ribosomal RNAs genes and a noncoding control region. Control region (CR), of 931 bp in length, was located between tRNA(Pro) and tRNA(Phe). The overall base composition of S. argentatus was 30.45% for A, 16.70% for G, 25.62% for T and 27.24% for C, with a slight AT bias of 56.07%.
Assuntos
Cyprinidae/genética , DNA Mitocondrial/genética , Genoma Mitocondrial , Animais , Composição de Bases/genética , Códon/genética , Fases de Leitura Aberta/genética , RNA de Transferência/genéticaRESUMO
The modification of typical age-related growth by environmental changes is poorly understood, In part because there is a lack of consensus at individual tree level regarding age-dependent growth responses to climate warming as stands develop. To increase our current understanding about how multiple drivers of environmental change can modify growth responses as trees age we used tree ring data of a mountain subtropical pine species along an altitudinal gradient covering more than 2,200 m of altitude. We applied mixed-linear models to determine how absolute and relative age-dependent growth varies depending on stand development; and to quantify the relative importance of tree age and climate on individual tree growth responses. Tree age was the most important factor for tree growth in models parameterised using data from all forest developmental stages. Contrastingly, the relationship found between tree age and growth became non-significant in models parameterised using data corresponding to mature stages. These results suggest that although absolute tree growth can continuously increase along tree size when trees reach maturity age had no effect on growth. Tree growth was strongly reduced under increased annual temperature, leading to more constant age-related growth responses. Furthermore, young trees were the most sensitive to reductions in relative growth rates, but absolute growth was strongly reduced under increased temperature in old trees. Our results help to reconcile previous contrasting findings of age-related growth responses at the individual tree level, suggesting that the sign and magnitude of age-related growth responses vary with stand development. The different responses found to climate for absolute and relative growth rates suggest that young trees are particularly vulnerable under warming climate, but reduced absolute growth in old trees could alter the species' potential as a carbon sink in the future.
Assuntos
Mudança Climática , Pinus/crescimento & desenvolvimento , Árvores/crescimento & desenvolvimento , Altitude , Clima , FlorestasRESUMO
Hepatitis B virus (HBV) is a causative reagent that frequently causes progressive liver diseases, leading to the development of acute, chronic hepatitis, cirrhosis, and eventually hepatocellular carcinoma (HCC). Despite several antiviral drugs including interferon-α and nucleotide derivatives are approved for clinical treatment for HBV, critical issues remain unresolved, e.g., low-to-moderate efficacy, adverse side effects, and resistant strains. In this study, novel Paeonol-phenylsulfonyl derivatives were synthesized and their antiviral effect against HBV was evaluated. The experimental results indicated that these compounds process significant antiviral potential, including the inhibition of viral antigen expression and secretion, and the suppression of HBV viral DNA replication. Among compounds synthesized in this research, compound 2-acetyl-5-methoxyphenyl 4-methoxybenzenesulfonate (7f) had the most potent inhibitory activity with IC50 value of 0.36 µM, and high selectivity index, SI (TC50/IC50) 47.75; which exhibited an apparent inhibition effect on viral gene expression and viral propagation in cell culture model. So, we believe our compounds could serve as reservoir for antiviral drug development.
Assuntos
Acetofenonas/farmacologia , Antivirais/farmacologia , Desenho de Fármacos , Vírus da Hepatite B/efeitos dos fármacos , Acetofenonas/síntese química , Acetofenonas/química , Antivirais/síntese química , Antivirais/química , Sobrevivência Celular , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade , Células Tumorais CultivadasRESUMO
The compound p-hydroxyacetophenone (PHAP) isolated from Artemisia morrisonensis was found to have potential anti-HBV effects in HepG2 2.2.15 cells. We clarified its antiviral mode further and HBV-transfected Huh7 cells were used as the platform. During viral gene expression, treatment with PHAP had no apparent effects on the viral precore/pregenomic RNA. However, the 2.4-kb preS RNA of viral surface gene increased significantly relative to the 2.1-kb S RNA with PHAP. Promoter activity analysis demonstrated that PHAP had a potent effect on augmenting the viral preS promoter activity. The subsequent increase in the large surface protein and induce endoplasmic reticular (ER) stress has been reported previously. Interestingly, PHAP specifically reduced ER stress related GRP78 RNA/protein levels, but not those of GRP94, in treated Huh7 cells while PHAP also led to the significant intracellular accumulation of virus. Moreover, treatment with the ER chaperone inducer thapsigargin relieved the inhibitory effect of PHAP based on the supernatant HBV DNA levels of HBV-expressed cells. In conclusion, this study suggests that the mechanism of HBV inhibition by PHAP might involve the regulation of viral surface gene expression and block virion secretion by interference with the ER stress signaling pathway.
Assuntos
Acetofenonas/farmacologia , Antivirais/farmacologia , Artemisia/química , Vírus da Hepatite B/efeitos dos fármacos , Extratos Vegetais/farmacologia , Acetofenonas/isolamento & purificação , Antivirais/isolamento & purificação , Linhagem Celular , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/fisiologia , Chaperona BiP do Retículo Endoplasmático , Antígenos de Superfície da Hepatite B/biossíntese , Hepatócitos/virologia , Humanos , Extratos Vegetais/isolamento & purificação , Regiões Promotoras Genéticas , Estresse Fisiológico , Ativação Transcricional/efeitos dos fármacos , Replicação Viral/efeitos dos fármacosRESUMO
Among several isosteviol-derived analogues, NC-8 (ent-16-oxobeyeran-19-N-methylureido) showed inhibitory potency against the hepatitis B virus (HBV) in HepG2 2.2.15 cells. Its anti-HBV mechanism was then next investigated in a human hepatoma cell culture system. Results showed that it specifically inhibited viral gene expression and reduced the level of encapsidated viral DNA intermediates in Huh7 cells that expressed replicating HBV. It also potently attenuated all viral promoter activity in HBV-expressing Huh7 cells, but not in cells lacking HBV expression. By examining its antiviral mechanism in cellular signaling pathways, NC-8 was found to inhibit the activity of the nuclear factor (NF)-κB element-containing promoter, but only slightly enhanced activities of activator protein (AP)-1- and interferon-sensitive response element (ISRE)-containing promoters in HBV-expressing cells. NC-8 also significantly eliminated NF-κB (p65/p50) and Toll-like receptor (TLR)2 proteins, but increased the IκBα protein level in a dose-dependent manner in HBV-transfected Huh7 cells, while these protein levels were apparently unchanged in non-transfected cells. Meanwhile, NC-8-treated nuclear extracts that co-expressed HBV inhibited the binding of NF-κB to the CS1 site of HBV major surface gene and specifically attenuated CS1-containing promoter activity. Taken together, this study suggests that the antiviral mechanism of NC-8 appears to be mediated by disturbing replication and gene expression of HBV and by inhibiting the host TLR2/NF-κB signaling pathway.
Assuntos
Antivirais/síntese química , Antivirais/farmacologia , Diterpenos do Tipo Caurano/farmacologia , Vírus da Hepatite B/efeitos dos fármacos , Antivirais/química , Sobrevivência Celular , Células Cultivadas , Diterpenos do Tipo Caurano/síntese química , Diterpenos do Tipo Caurano/química , Relação Dose-Resposta a Droga , Humanos , Testes de Sensibilidade Microbiana , Conformação Molecular , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
The compound LPRP-Et-97543 was isolated from Liriope platyphylla roots and was observed to have potential anti-viral effects in HepG2.2.15 cells against hepatitis B virus (HBV). The antiviral mode was further clarified, and the HBV-transfected Huh7 cells were used as the platform. During viral gene expression, LPRP-Et-97543 treatment had apparent effects on the viral precore/pregenomic and S/preS RNA. Promoter activity analysis demonstrated that LPRP-Et-97543 significantly reduced Core, S, and preS but not X promoter activities. Further examination showed that putative signaling pathways were involved in this inhibitory effect, indicating that NF-κB may serve a putative mediator of HBV gene regulation with LPRP-Et-97543. In addition, the nuclear expression of p65/p50 NF-κB member proteins was attenuated with LPRP-Et-97543 and augmented cytoplasmic IκBα protein levels but without affecting the expression of these proteins in HBV non-transfected cells during treatment. Moreover, LPRP-Et-97543 reduced the binding activity of NF-κB protein to CS1 element of HBV surface gene in a gel retardation analysis and inhibited CS1 containing promoter activity in HBV expressed cells. However, HBV transfection significantly enhances CS1 containing promoter activity without compound treatment in cells. Finally, transfection of the p65 expression plasmid significantly reversed the inhibitory effect of LPRP-Et-97543 on the replicated HBV DNA level in HBV positive cells. In conclusion, this study suggests that the mechanism of HBV inhibition by LPRP-Et-97543 may involve the feedback regulation of viral gene expression and viral DNA replication by HBV viral proteins, which interferes with the NF-κB signaling pathway.
Assuntos
Antivirais/farmacologia , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/fisiologia , Liliaceae/química , Extratos Vegetais/farmacologia , Replicação Viral/efeitos dos fármacos , Antivirais/isolamento & purificação , Linhagem Celular , Humanos , Extratos Vegetais/isolamento & purificaçãoRESUMO
The biotransformation of dihydroisosteviol with Absidia pseudocylindrospora ATCC 24169, Streptomyces griseus ATCC 10137, Mucor recurvatus MR36, and Aspergillus niger BCRC 31130 yielded 15 metabolites, eight of which were previously unknown. Structures of metabolites were established by 2D NMR techniques and HRMS data, two of which were further corroborated by chemical means, and another via single-crystal X-ray diffraction analysis. Subsequently, two steroidogenic cell lines (Y-1 mouse adrenal tumor and MA-10 mouse Leydig tumor cells) were used in a reverse transcription-PCR analysis to assess the effects of all compounds on steroidogenic gene expressions using forskolin as a positive control. The tested gene expressions included steroidogenic factor-1 (SF-1), steroidogenic acute regulatory protein (StAR), and cytochrome P450 side-chain cleavage (P450scc) enzyme. Gene expression profiles showed that ten of the tested compounds effectively suppressed P450SCC mRNA expression in both Y-1 and MA-10 cells. Several induced SF-1 gene expression and two enhanced StAR gene expression in Y-1 cells. By contrast, in MA-10 cells, one compound effectively suppressed StAR mRNA expression, whereas for others effectively suppressed SF-1 gene expression. The results suggest that analogs of dihydroisosteviol can be potential modulators to alter steroidogenic gene expressions and subsequent enzyme activities.
Assuntos
Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Diterpenos do Tipo Caurano/farmacologia , Expressão Gênica/efeitos dos fármacos , Fosfoproteínas/metabolismo , Fator Esteroidogênico 1/metabolismo , Stevia/química , Animais , Bactérias , Biotransformação , Linhagem Celular Tumoral , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Colforsina/farmacologia , Diterpenos do Tipo Caurano/química , Diterpenos do Tipo Caurano/metabolismo , Fungos , Camundongos , Estrutura Molecular , Fosfoproteínas/genética , RNA Mensageiro/metabolismo , Fator Esteroidogênico 1/genéticaRESUMO
Eleven compounds were isolated from the methanolic extract of the leaves of Solanum erianthum D. Don, including five alpha-linolenic acid analogs, alpha-linolenic acid (1), 13S-hydroxy-9(Z),11(E)-octadecadienoic acid (2), 9S-hydroxy-10(E),12(Z), 15(Z)-octadectrienoic acid (3), 9(Z),11(E)-octadecadienoic acid (4), and octadecanoic acid (5); two benzofuran-type lactones, loliolide (6) and dihydroactinidiolide (7); two steroidal alkaloids, solasonine (8) and solamargine (9); a flavonol glycoside, camelliaside C (10); and a flavone, 5-methoxy-(3,4"-dihydro-3",4"-diacetoxy)-2",2'-dimethylpyrano-(7,8:5",6")-flavone (11). Among these isolated compounds, 9 showed the most potent activity against HBsAg, with an IC50 of 1.57 microM, followed by 8 (IC50 is 5.89 microM). In the testing against HBeAg, 11 was the only active compound with an IC50 of 36.11 microM. Compound 9 also revealed strong inhibition of DNA replication towards HBV and its IC50 was 2.17 microM. However, alpha-linolenic acid (1) showed a prominent selected index (SI), both in anti-HBsAg and inhibition of DNA replication with SI values of 7.75 and 7.18, respectively. This is the first report that unsaturated fatty acid 1, steroidal alkaloid glycoside 9 and flavone 11, all showed excellent activity against HBV. These results provide lead candidates in the development of anti-HBV drugs from natural sources.
Assuntos
Antivirais/farmacologia , Ácidos Graxos Insaturados/farmacologia , Flavonas/farmacologia , Glicosídeos/farmacologia , Vírus da Hepatite B/efeitos dos fármacos , Solanum/química , Antivirais/química , Sobrevivência Celular , Ácidos Graxos Insaturados/química , Flavonas/química , Glicosídeos/química , Células Hep G2 , Humanos , Concentração Inibidora 50 , Estrutura MolecularRESUMO
This article documents the addition of 139 microsatellite marker loci and 90 pairs of single-nucleotide polymorphism sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Aglaoctenus lagotis, Costus pulverulentus, Costus scaber, Culex pipiens, Dascyllus marginatus, Lupinus nanus Benth, Phloeomyzus passerini, Podarcis muralis, Rhododendron rubropilosum Hayata var. taiwanalpinum and Zoarces viviparus. These loci were cross-tested on the following species: Culex quinquefasciatus, Rhododendron pseudochrysanthum Hay. ssp. morii (Hay.) Yamazaki and R. pseudochrysanthum Hayata. This article also documents the addition of 48 sequencing primer pairs and 90 allele-specific primers for Engraulis encrasicolus.
Assuntos
Bases de Dados Genéticas , Animais , Artrópodes/genética , Repetições de Microssatélites , Dados de Sequência Molecular , Plantas/genética , Vertebrados/genéticaRESUMO
Helicobacter pylori infection is associated with an increased risk for development of duodenal ulcers, gastric ulcers, gastric adenocarcinomas and gastric lymphomas. However, resistant strains have developed because of antibiotic treatment. In this study, the water, acetone, chloroform and methanol extracts of two Solancaceae plants, Solanum erianthum and Solanum torvum (ST), were tested for their anti-H. pylori activity. All of ST extracts were able to inhibit the growth of H. pylori and showed better activities against antibiotic strains than the reference strain. Among them, chloroform extract of ST (ST-C) possessed the strongest ability to inhibit H. pylori growth. Association assay was performed by the ST-C showing that ST-C was able to interrupt the association of bacteria to host cells. Furthermore, H. pylori-induced apoptosis could also be efficiently suppressed by the ST-C. It was able to interfere with the interaction between bacteria and host cells and also target H. pylori-induced gastric injury by suppressing apoptosis. Therefore, ST-C may offer a new approach for the treatment of H. pylori. Further studies on the elucidation of the molecular mechanisms of the growth inhibition on H. pylori by ST-C, and to identify active compounds in the plants are in progress.
Assuntos
Antibacterianos/farmacologia , Apoptose/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Mucosa Gástrica/efeitos dos fármacos , Helicobacter pylori/efeitos dos fármacos , Extratos Vegetais/farmacologia , Solanum , Proteínas Reguladoras de Apoptose/metabolismo , Aderência Bacteriana/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Relação Dose-Resposta a Droga , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Células Epiteliais/patologia , Mucosa Gástrica/metabolismo , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Helicobacter pylori/crescimento & desenvolvimento , HumanosRESUMO
The hepatitis B virus surface gene consists of a single open reading frame divided into three coding regions: pre-S1, pre-S2, and S. By alternate translation at each of the three initiation codons, L, M, and S proteins can be synthesized. Studies have shown that M protein is not essential for viral replication, virion morphogenesis, or in vitro infectivity. In this study, we show that native M protein can regulate surface gene expression at the transcriptional level. The regulatory effect of M protein is mediated through the CCAAT box within the S promoter. Deletion mapping analysis indicated that the transactivating effect of M protein is mediated through amino acids 1-57 of M protein (the MHBs(au) domain), although its maximal transactivation activity coincides with that of the pre-S2 domain. This conclusion is supported by the fact that disruption of the putative V8 protease site at the pre-S2/S domain junction not only rendered M protein incapable of transactivating the S promoter but also inactivated its nuclear translocation potential. Immunoprecipitation and immunoblot experiments demonstrated that pre-S2 interacts with the three subunits of the CCAAT box-binding factor/nuclear factor Y, the cognate binding protein of the CCAAT box. These results demonstrate and define a novel regulatory role of M protein, which, under natural conditions, may undergo a proteolytic process to generate an MHBs(au) species that will be translocated inside the nucleus, where it will interact with the CCAAT box-binding factor to regulate surface gene expression. Because the CCAAT box is located at a fixed position within numerous promoters, these observations might provide a plausible explanation for hepatitis B virus-associated hepatocarcinogenesis.