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1.
Gut ; 66(10): 1853-1861, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-27436270

RESUMO

OBJECTIVE: Silibinin is a flavonolignan that is well established for its robust antiviral activity against HCV infection and has undergone several clinical trials for the management of hepatitis C. Despite its potency, silibinin suffers from poor solubility and bioavailability, restricting its clinical use. To overcome this limitation, we developed highly bioavailable silibinin nanoparticles (SB-NPs) and evaluated their efficiency against HCV infection. DESIGN: SB-NPs were prepared using a nanoemulsification technique and were physicochemically characterised. Infectious HCV culture systems were used to evaluate the influence of SB-NP on the virus life cycle and examine their antioxidant activity against HCV-induced oxidative stress. The safety profiles of SB-NP, in vivo pharmacokinetic studies and antiviral activity against infection of primary human hepatocytes were also assessed. RESULTS: SB-NP consisted of nanoscale spherical particles (<200 nm) encapsulating amorphous silibinin at >97% efficiency and increasing the compound's solubility by >75%. Treatment with SB-NP efficiently restricted HCV cell-to-cell transmission, suggesting that they retained silibinin's robust anti-HCV activity. In addition, SB-NP exerted an antioxidant effect via their free radical scavenging function. Oral administration of SB-NP in rodents produced no apparent in vivo toxicity, and pharmacokinetic studies revealed an enhanced serum level and superior biodistribution to the liver compared with non-modified silibinin. Finally, SB-NP efficiently reduced HCV infection of primary human hepatocytes. CONCLUSIONS: Due to SB-NP's enhanced bioavailability, effective anti-HCV activity and an overall hepatoprotective effect, we suggest that SB-NP may be a cost-effective anti-HCV agent that merits further evaluation for the treatment of hepatitis C.


Assuntos
Antioxidantes/farmacologia , Hepacivirus/efeitos dos fármacos , Silimarina/farmacologia , Animais , Antioxidantes/administração & dosagem , Antioxidantes/farmacocinética , Células Cultivadas , Sistemas de Liberação de Medicamentos , Hepacivirus/patogenicidade , Hepatócitos/virologia , Humanos , Estágios do Ciclo de Vida/efeitos dos fármacos , Masculino , Nanosferas , Ratos , Silibina , Silimarina/administração & dosagem , Silimarina/farmacocinética
2.
J Hepatol ; 62(3): 541-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25450204

RESUMO

BACKGROUND & AIMS: A vaccine against hepatitis C virus (HCV) is unavailable and cost-effective antivirals that prevent HCV infection and re-infection, such as in the transplant setting, do not exist. In a search for novel and economical prophylactic agents, we examined the antiviral activity of saikosaponins (SSa, SSb2, SSc, and SSd) from Bupleurum kaoi root (BK) as entry inhibitors against HCV infection. METHODS: Infectious HCV culture systems were used to examine the effect of saikosaponins on the complete virus life cycle (entry, RNA replication/translation, and particle production). Antiviral activity against various HCV genotypes, clinical isolates, and infection of primary human hepatocytes were also evaluated. RESULTS: BK and the saikosaponins potently inhibited HCV infection at non-cytotoxic concentrations. These natural agents targeted early steps of the viral life cycle, while leaving replication/translation, egress, and spread relatively unaffected. In particular, we identified SSb2 as an efficient inhibitor of early HCV entry, including neutralization of virus particles, preventing viral attachment, and inhibiting viral entry/fusion. Binding analysis, using soluble viral glycoproteins, demonstrated that SSb2 acted on HCV E2. Moreover, SSb2 inhibited infection by several genotypic strains and prevented binding of serum-derived HCV onto hepatoma cells. Finally, treatment with the compound blocked HCV infection of primary human hepatocytes. CONCLUSIONS: Due to its potency, SSb2 may be of value for development as an antagonist of HCV entry and could be explored as prophylactic treatment during the course of liver transplantation.


Assuntos
Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Hepacivirus/fisiologia , Ácido Oleanólico/análogos & derivados , Saponinas/farmacologia , Internalização do Vírus/efeitos dos fármacos , Animais , Antivirais/isolamento & purificação , Antivirais/toxicidade , Bupleurum , Linhagem Celular , Hepatite C/prevenção & controle , Hepatócitos/efeitos dos fármacos , Hepatócitos/virologia , Humanos , Transplante de Fígado , Masculino , Ácido Oleanólico/isolamento & purificação , Ácido Oleanólico/farmacologia , Ácido Oleanólico/toxicidade , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Ratos , Ratos Sprague-Dawley , Saponinas/isolamento & purificação , Saponinas/toxicidade , Vírion/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
3.
ScientificWorldJournal ; 2014: 978525, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25133268

RESUMO

Extracts from natural plants have been used in traditional medicine for many centuries worldwide. Artocarpus communis is one such plant that has been used to treat liver cirrhosis, hypertension, and diabetes. To our knowledge, this study is the first to investigate the antihepatoma activity of A. communis toward HepG2 and PLC/PRF/5 cells and the first to explore the relationship between antihepatoma activity and the active compound artocarpin content in different fractions of A. communis. A. communis methanol extract and fractions induced dose-dependent reduction of tumor cell viability. DNA laddering analysis revealed that A. communis extract and fractions did not induce apoptosis in HepG2 and PLC/PRF/5 cells. Instead, acridine orange staining revealed that A. communis triggered autophagic cell death in a dose-dependent manner. The antihepatoma activity of A. communis is attributable to artocarpin. The fractions with the highest artocarpin content were also the fractions with the highest antihepatoma activity in the following order: dichloromethane fraction > methanol extract > ethyl acetate fraction > n-butanol fraction > n-hexane fraction. Taken together, A. communis showed antihepatoma activity through autophagic cell death. The effect was related to artocarpin content. Artocarpin could be considered an indicator of the anticancer potential of A. communis extract.


Assuntos
Antineoplásicos/farmacologia , Artocarpus/química , Lectinas de Ligação a Manose/farmacologia , Extratos Vegetais/farmacologia , Lectinas de Plantas/farmacologia , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Células Hep G2 , Humanos , Lectinas de Ligação a Manose/análise , Extratos Vegetais/química , Lectinas de Plantas/análise
4.
BMC Microbiol ; 13: 187, 2013 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-23924316

RESUMO

BACKGROUND: We previously identified two hydrolyzable tannins, chebulagic acid (CHLA) and punicalagin (PUG) that blocked herpes simplex virus type 1 (HSV-1) entry and spread. These compounds inhibited viral glycoprotein interactions with cell surface glycosaminoglycans (GAGs). Based on this property, we evaluated their antiviral efficacy against several different viruses known to employ GAGs for host cell entry. RESULTS: Extensive analysis of the tannins' mechanism of action was performed on a panel of viruses during the attachment and entry steps of infection. Virus-specific binding assays and the analysis of viral spread during treatment with these compounds were also conducted. CHLA and PUG were effective in abrogating infection by human cytomegalovirus (HCMV), hepatitis C virus (HCV), dengue virus (DENV), measles virus (MV), and respiratory syncytial virus (RSV), at µM concentrations and in dose-dependent manners without significant cytotoxicity. Moreover, the natural compounds inhibited viral attachment, penetration, and spread, to different degrees for each virus. Specifically, the tannins blocked all these steps of infection for HCMV, HCV, and MV, but had little effect on the post-fusion spread of DENV and RSV, which could suggest intriguing differences in the roles of GAG-interactions for these viruses. CONCLUSIONS: CHLA and PUG may be of value as broad-spectrum antivirals for limiting emerging/recurring viruses known to engage host cell GAGs for entry. Further studies testing the efficacy of these tannins in vivo against certain viruses are justified.


Assuntos
Antivirais/farmacologia , Benzopiranos/farmacologia , Glucosídeos/farmacologia , Glicosaminoglicanos/metabolismo , Taninos Hidrolisáveis/farmacologia , Receptores Virais/metabolismo , Viroses/virologia , Internalização do Vírus/efeitos dos fármacos , Vírus/efeitos dos fármacos , Animais , Linhagem Celular , Relação Dose-Resposta a Droga , Humanos , Viroses/metabolismo , Fenômenos Fisiológicos Virais/efeitos dos fármacos
5.
BMC Complement Altern Med ; 13: 348, 2013 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-24325567

RESUMO

BACKGROUND: Many natural products used in preventive medicine have also been developed as cosmeceutical ingredients in skin care products, such as Scutellaria baicalensis and Gardenia jasminoides. Norartocarpetin is one of the antioxidant and antityrosinase activity compound in Artocarpus communis; however, the cytotoxicity, skin irritation and antimelanogenesis mechanisms of norartocarpetin have not been investigated yet. METHODS: In the present study, cell viability in vitro and skin irritation in vivo are used to determine the safety of norartocarpetin. The melanogenesis inhibition of norartocarpetin was determined by cellular melanin content and tyrosinase in B16F10 melanoma cell. Moreover, we examined the related-melanogenesis protein by western blot analysis for elucidating the antimelanogenesis mechanism of norartocarpin. RESULTS: The result of the present study demonstrated that norartocarpetin not only present non-cytotoxic in B16F10 and human fibroblast cells but also non-skin irritation in mice. Moreover, our result also first found that norartocarpetin downregulated phospho-cAMP response element-binding (phospho-CREB) and microphthalmia-associated transcription factor (MITF) expression, which in turn decreased both synthesis of tyrosinases (TRP-1 and TRP-2) and cellular melanin content. This process is dependent on norartocarpetin phosphorylation by mitogen-activated protein kinases such as phospho-JNK and phospho-p38, and it results in decreased melanogenesis. CONCLUSION: The present study suggests that norartocarpetin could be used as a whitening agent in medicine and/or cosmetic industry and need further clinical study.


Assuntos
Artocarpus/química , Sobrevivência Celular/efeitos dos fármacos , Flavonas/farmacologia , Monofenol Mono-Oxigenase/efeitos dos fármacos , Extratos Vegetais/farmacologia , Pele/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Flavonas/química , Humanos , Masculino , Medicina Tradicional , Melaninas/análise , Melaninas/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Fator de Transcrição Associado à Microftalmia/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Extratos Vegetais/química , Testes de Irritação da Pele
6.
Int J Mol Sci ; 14(2): 3860-73, 2013 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-23403620

RESUMO

Administration of antioxidants and anti-inflammatory agents is an effective strategy for preventing ultraviolet (UV) irradiation-induced skin damage. Artocarpus communis possesses several pharmacological activities, such as antioxidant, anticancer and anti-inflammation. However, the photoprotective activity of methanol extract of A. communis heartwood (ACM) in ultraviolet irradiation-induced skin damage has not yet been investigated. The present study was performed using ultraviolet absorption, histopathological observation, antioxidant and anti-inflammation assays to elucidate the mechanism of the photoprotective activity of ACM. Our results indicated that ACM displayed a UVA and UVB absorption effect and then effectively decreased scaly skin, epidermis thickness and sunburn cells during ultraviolet irradiation in hairless mice. ACM not only decreased ultraviolet irradiation-mediated oxidative stress, including lowering the overproduction of reactive oxygen species and lipid peroxidation (p < 0.05), but also reduced the levels of pro-inflammatory cytokines, including tumor necrosis factor-α (TNF-α) and interleukin 1ß. Additionally, ACM can decrease the synthesis of cytosolic phospholipase A2, cyclooxygenase, inducible nitric oxide synthase and vascular cell adhesion molecular-1 via inhibiting TNF-α-independent pathways (p < 0.05) in UVB-mediated inflammation and formation of sunburn cells. Consequently, we concluded that ACM extract has a photoprotective effect against UVB-induced oxidative stress and inflammation due to its sunscreen property, and its topical formulations may be developed as therapeutic and/or cosmetic products in further studies.

7.
J Virol ; 85(9): 4386-98, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21307190

RESUMO

Herpes simplex virus 1 (HSV-1) is a common human pathogen that causes lifelong latent infection of sensory neurons. Non-nucleoside inhibitors that can limit HSV-1 recurrence are particularly useful in treating immunocompromised individuals or cases of emerging acyclovir-resistant strains of herpesvirus. We report that chebulagic acid (CHLA) and punicalagin (PUG), two hydrolyzable tannins isolated from the dried fruits of Terminalia chebula Retz. (Combretaceae), inhibit HSV-1 entry at noncytotoxic doses in A549 human lung cells. Experiments revealed that both tannins targeted and inactivated HSV-1 viral particles and could prevent binding, penetration, and cell-to-cell spread, as well as secondary infection. The antiviral effect from either of the tannins was not associated with induction of type I interferon-mediated responses, nor was pretreatment of the host cell protective against HSV-1. Their inhibitory activities targeted HSV-1 glycoproteins since both natural compounds were able to block polykaryocyte formation mediated by expression of recombinant viral glycoproteins involved in attachment and membrane fusion. Our results indicated that CHLA and PUG blocked interactions between cell surface glycosaminoglycans and HSV-1 glycoproteins. Furthermore, the antiviral activities from the two tannins were significantly diminished in mutant cell lines unable to produce heparan sulfate and chondroitin sulfate and could be rescued upon reconstitution of heparan sulfate biosynthesis. We suggest that the hydrolyzable tannins CHLA and PUG may be useful as competitors for glycosaminoglycans in the management of HSV-1 infections and that they may help reduce the risk for development of viral drug resistance during therapy with nucleoside analogues.


Assuntos
Antivirais/metabolismo , Glicoproteínas/antagonistas & inibidores , Glicosaminoglicanos/antagonistas & inibidores , Herpesvirus Humano 1/efeitos dos fármacos , Taninos Hidrolisáveis/metabolismo , Proteínas Virais/antagonistas & inibidores , Internalização do Vírus/efeitos dos fármacos , Animais , Antivirais/isolamento & purificação , Benzopiranos/isolamento & purificação , Benzopiranos/metabolismo , Linhagem Celular , Chlorocebus aethiops , Glucosídeos/isolamento & purificação , Glucosídeos/metabolismo , Herpesvirus Humano 1/fisiologia , Humanos , Taninos Hidrolisáveis/isolamento & purificação , Testes de Sensibilidade Microbiana , Terminalia/química , Ensaio de Placa Viral , Inativação de Vírus
8.
J Nanosci Nanotechnol ; 12(3): 2022-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22755015

RESUMO

Silymarin, a well known hepatoprotective drug, has been routinely used in treating liver disorders. However, its bioavailability and therapeutic efficiency are limited by the poor aqueous solubility. In this study, we used the nanoprecipitation technique to develop a nanoparticles system to improve the solubility of silymarin. The newly developed silymarin nanoparticles were characterized for mean particle size, morphology, intermolecular interaction, crystalline features and dissolution property, as well as assessing for antioxidant activities. Results indicated that a drastic change in the physiochemical properties of silymarin was noted in the form of nanoparticles, as displayed by the extremely small particle size (46.1 +/- 1.73 nm), the formation of intermolecular hydrogen bonding between silymarin and matrix of nanoparticles, and the rendering of amorphous state. These phenomena have contributed to the enhanced dissolution property of silymarin nanoparticles, as well as a greater potency in DPPH radical scavenging, anti-superoxide anion formation, and superoxide anion scavenging activities than the crude silymarin. The present study concludes that silymarin nanoparticles have an improved physicochemical property as demonstrated by an increased solubility and enhanced antioxidant activities.


Assuntos
Antioxidantes/farmacologia , Nanopartículas , Silimarina/farmacologia , Antioxidantes/química , Microscopia Eletrônica de Transmissão , Silimarina/química , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Artigo em Inglês | MEDLINE | ID: mdl-22474533

RESUMO

Xiao-Chai-Hu-Tang (XCHT), a traditional Chinese medicine formula consisting of seven medicinal plants, is used in the treatment of various diseases. We show here that XCHT could protect type-1 diabetic mice against diabetic nephropathy, using streptozotocin (STZ)-induced diabetic mice and high-glucose (HG)-exposed rat mesangial cell (RMC) as models. Following 4 weeks of oral administration with XCHT, renal functions and renal hypertrophy significantly improved in the STZ-diabetic mice, while serum glucose was only moderately reduced compared to vehicle treatment. Treatment with XCHT in the STZ-diabetic mice and HG-exposed RMC resulted in a decrease in expression levels of TGF-ß1, fibronectin, and collagen IV, with concomitant increase in BMP-7 expression. Data from DPPH assay, DHE stain, and CM-H(2)DCFDA analysis indicated that XCHT could scavenge free radicals and inhibit high-glucose-induced ROS in RMCs. Taken together, these results suggest that treatment with XCHT can improve renal functions in STZ-diabetic mice, an effect that is potentially mediated through decreasing oxidative stress and production of TGF-ß1, fibronectin, and collagen IV in the kidney during development of diabetic nephropathy. XCHT, therefore merits further investigation for application to improve renal functions in diabetic disorders.

10.
Artigo em Inglês | MEDLINE | ID: mdl-19808846

RESUMO

Phyllanthus urinaria Linnea (Euphorbiaceae) is one of the traditional medicinal plants widely used by oriental people to treat various diseases. We have previously demonstrated that the acetone extract of P. urinaria inhibits herpes simplex virus type 2 (HSV-2) but not HSV-1 infection. In a continuing effort to clarify the antiviral mechanisms of P. urinaria, we isolated the pure compound excoecarianin from the whole plant of P. urinaria through acetone extraction, and investigated its anti-HSV-1 and HSV-2 activities. Our results indicated that excoecarianin protected Vero cells from HSV-2 but not HSV-1 infection, and its 50% inhibitory concentration (IC(50)) was 1.4 ± 0.1 µM. The antiviral effective concentration of excoecarianin did not affect the viability or the morphology of Vero cells. Although excoecarianin inhibited HSV-2 infection, the inhibitory effect, however, was most prominent when excoecarianin was concurrently added with the virus. Pretreatment of Vero cells with excoecarianin with removal of the drug prior to infection did not yield any antiviral effects, and the same observation was made for post viral entry treatment. Subsequent studies revealed that excoecarianin inactivated HSV-2 virus particles to prevent viral infection. A synergistic antiviral effect against HSV-2 was also observed when Vero cells were treated with a combination of acyclovir (ACV) and excoecarianin. These results suggested that excoecarianin merits to be further explored as an entry inhibitor against HSV-2 and could potentially be investigated for combinatorial drug treatment with nucleoside analogues such as ACV in therapeutic management of HSV-2 infection.

11.
J Sci Food Agric ; 91(15): 2777-84, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21725979

RESUMO

BACKGROUND: Persistent activation of hepatic stellate cells (HSC-T6) has been known to cause liver fibrosis. In this study, our objective was to investigate the effects of chebulagic acid and chebulinic acid, two hydrolysable tannins of tropical almond (Terminalia chebula) fruits, on collagen synthesis and signal transduction in transforming growth factor-ß1-stimulated HSC-T6 cells. The expression of Smad2, Smad3, Smad4, collagen I(α1)/III, and plasminogen activator inhibitor 1 (PAI-1) mRNAs was determined by reverse-transcription polymerase chain reaction and their protein levels were assessed by western blotting. RESULTS: Results showed that chebulagic acid and chebulinic acid at 20 µmol L(-1) exhibited cytotoxic and anti-proliferative effects on HSC-T6 cells. They also significantly decreased the expression of Smd2, Smad3 and Smad4, and the synthesis of collagen, procollagen I (α1) and III, as well as suppressing the activation of PAI-1; these events consequently facilitated the resolution of fibrosis. CONCLUSION: These results indicate that both chebulagic acid and chebulinic acid possess antifibrotic activity, and their mechanism of action could be through the inhibition of the Smad pathway.


Assuntos
Benzopiranos/uso terapêutico , Colágeno/biossíntese , Glucosídeos/uso terapêutico , Células Estreladas do Fígado/efeitos dos fármacos , Taninos Hidrolisáveis/uso terapêutico , Cirrose Hepática/tratamento farmacológico , Fitoterapia , Terminalia/química , Animais , Benzopiranos/farmacologia , Western Blotting , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Colágeno Tipo I/biossíntese , Colágeno Tipo III/biossíntese , Citotoxinas/farmacologia , Citotoxinas/uso terapêutico , Frutas , Glucosídeos/farmacologia , Taninos Hidrolisáveis/farmacologia , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Inibidor 1 de Ativador de Plasminogênio/metabolismo , RNA Mensageiro/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad Reguladas por Receptor/metabolismo , Fator de Crescimento Transformador beta1
12.
Pharm Biol ; 48(2): 221-6, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20645845

RESUMO

This study evaluates the possible potency of the anti-hyperlipidemic effect of spider brake [(Pteris multifida Poiret (Pteridaceae)]. We investigated this by feeding the hyperlipidemic Sprague-Dawley rats, caused by a high cholesterol diet, with lyophilized powder of spider brake (LSB) and compared the result with the rats fed with beta-sitosterol. The results indicated that the administration of lyophilized powder of spider brake (LSB) lowered the hyperlipidemic level on rats. The relative weights of the liver, adipose tissue, and relative adipose tissue of 10% substitutions of LSB group (LSB-10) showed a significant decrease (P < 0.05) by 6%, 15.9%, and 14.3% in contrast to the untreated counterparts (control), respectively. A significantly lower (P < 0.05) plasma TG, low density lipoprotein cholesterol, low density lipoprotein cholesterol/high density lipoprotein cholesterol ratio, liver CH, and TG contents were also observed in LSB-10 compared to the untreated counterparts (by 36.8%, 21%, 18.7%, 10.2% and 14.3% reduction, respectively). Simultaneously, the wet fecal weight, dry fecal weight, nitrogen compounds, excretion of neutral steroids, and bile acids significantly (P < 0.05) increased by 9.6%, 10.6%, 23.7%, 9.7%, and 3.4% respectively. The results showed that LSB could cause not only a reduction in CH and TG, but also could increase the excretion of lipids and metabolic by-products via the intestinal tract.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Hiperlipidemias/prevenção & controle , Hipolipemiantes/uso terapêutico , Extratos Vegetais/uso terapêutico , Pteris/química , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/patologia , Adiposidade/efeitos dos fármacos , Animais , Ácidos e Sais Biliares/análise , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/química , Fezes/química , Hiperlipidemias/induzido quimicamente , Hiperlipidemias/metabolismo , Hiperlipidemias/patologia , Hipolipemiantes/administração & dosagem , Hipolipemiantes/química , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipídeos/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Nitrogênio/análise , Tamanho do Órgão/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Pós , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Esteróis/análise
13.
Phytomedicine ; 53: 62-69, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30668413

RESUMO

BACKGROUND: Despite the advent of direct-acting antivirals (DAAs), HCV remains an important public health problem globally. There is at present no effective vaccine against the virus, and the DAAs in current use cannot prevent de novo infection, including in liver transplant setting wherein donor livers inevitably become re-infected. Developing inhibitors to HCV entry using nature-derived small molecules may help to expand/complement the current treatment options. PURPOSE: In this study, we explored the effect of the plant alkaloid berberine (BBR) on HCV early viral entry. METHODS: Cell culture-derived HCV (HCVcc), viral pseudoparticles bearing HCV glycoproteins (HCVpp), and entry-related assays were employed to assess BBR's bioactivity. Molecular docking was used to predict BBR-HCV glycoproteins interaction, and the compound's antiviral activity was confirmed against HCVcc infection of primary human hepatocytes (PHHs). RESULTS: BBR specifically impeded HCVcc attachment and entry/fusion steps without inactivating the free virus particles or affecting the expression of host cell entry factors and post-entry viral replication. BBR also effectively inhibited infection by viral pseudoparticles expressing HCV E1/E2 glycoproteins and molecular docking analysis pointed at potential interaction with HCV E2. Finally, BBR could suppress HCVcc infection of PHHs. CONCLUSIONS: We identified BBR as a potent HCV entry inhibitor, which merits further evaluation particularly for use in transplant setting against graft re-infection by HCV.


Assuntos
Antivirais/farmacologia , Berberina/farmacologia , Hepacivirus/efeitos dos fármacos , Proteínas do Envelope Viral/metabolismo , Antivirais/química , Berberina/química , Células Cultivadas , Hepacivirus/patogenicidade , Hepacivirus/fisiologia , Hepatite C/tratamento farmacológico , Hepatócitos/efeitos dos fármacos , Hepatócitos/virologia , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Simulação de Acoplamento Molecular , Terapia de Alvo Molecular , Internalização do Vírus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
14.
Antiviral Res ; 77(1): 14-9, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17931713

RESUMO

Yin Chen Hao Tang (YCHT) is one of the most frequently used prescriptions in the long history of traditional Chinese medicine practice. The prescription contains three Chinese herbs, namely Artemisia capillaries Thunb. (Compositae), Rheum officinale Baillon (Polygonaceae), and Gardenia jasminoids Ellis (Rubiaceae), and has been widely used to treat acute hepatitis with jaundice. In this study, the in vitro anti-HSV-1 and HSV-2 activities of the water extract of YCHT were investigated. Results showed that YCHT water extract inhibited both HSV-1 and HSV-2 infections. However, the inhibition was more effective against HSV-2 than against HSV-1. The IC(50) and IC(90) values of YCHT water extract against HSV-1 infection were in the range of 142.5-150.1 and 191.3-393.9 microg/ml, and against HSV-2 infection they were in the range of 19.6-29.4 and 42.2-97.7 microg/ml, respectively. The water extract of YCHT showed no cytotoxic effect at a concentration of 500 microg/ml or below, and had a CC(50) value of 850.7+/-1.7 microg/ml. The prescription was found to diminish HSV-2 infectivity in a dose-dependent manner, and the activity was influenced by the incubation periods and the incubation temperatures. Concurrent addition of virus with YCHT or pre-treatment of the virus with the prescription extract both protected the cells from infection. In summary, the water extract of YCHT was concluded to inhibit infections by HSV-1 and HSV-2 and this effect was likely mediated through direct inactivation of the virus infectivity.


Assuntos
Antivirais/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 2/efeitos dos fármacos , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fitoterapia
15.
J Gastroenterol Hepatol ; 23(7 Pt 2): e290-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18522681

RESUMO

BACKGROUND AND AIM: Huang-lian-jie-du-tang (HLJDT; Japanese name, oren-gedoku-to) is a traditional Chinese medicine prescription known to possess anti-inflammatory activity. Our study reports here for the first time the anticancer effect of HLJDT in two human liver cancer cell lines, Hep G2 and PLC/PRF/5. METHODS: Inhibition of cell proliferation by HLJDT was measured by sodium 3'-(1-(phenylamino-carbonyl)-3,4-tetrazolium)-bis(4-methoxy-6-nitro) benzene-sulfonic acid hydrate (XTT) assay. Clonogenic assay was used to elucidate the possible differences in long-term effects of HLJDT on human liver cancer cells. Cell cycle distribution was determined by flow cytometry. Apoptosis was detected using electrophoresis and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick endlabeling (TUNEL) assay. Protein expressions were determined by immunoblot assay. The activity of nuclear factor-kappa B (NF-kappaB) was determined by Trans-AM ELISA kit. In vivo tumor activity was assessed by xenograft study. RESULTS: HLJDT significantly increased the expression of inactivated phospho-Cdc2 and phospho-Cdc25C, and decreased the levels of cyclin A, cyclin B1, Cdc2, and Cdc25C, thereby contributing to cell-cycle arrest. HLJDT increased the expression of Bax and Bak, but decreased the level of Bcl-2 and Bcl-XL, and subsequently triggered the mitochondrial apoptotic pathway. In addition, HLJDT also inhibited cell-survival signaling by enhancing the amount of IkappaBalpha in the cytoplasm, reducing the level and activity of NF-kappaB in the nucleus, and subsequently attenuating the expression of Bcl-XL in Hep G2 and PLC/PRF/5 cells(.) The inhibitory effect mediated by HLJDT on cell growth was also demonstrated in a nude mouse model, in which the liver cancer cells induced tumor xenograft shrank considerably following treatment with HLJDT. CONCLUSIONS: Taken together, these results suggest a potential anticancer effect of HLJDT against human liver cancer cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Relação Dose-Resposta a Droga , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , NF-kappa B/metabolismo , Fosforilação , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Chemotherapy ; 54(2): 77-83, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18332627

RESUMO

BACKGROUND: Long Dan Xie Gan Tan (LDXGT), a decoction of radix gentianae for purging the pathogenic inflammation of the liver, is a widely used prescription among many in traditional Chinese medicine. The prescription is primarily used to treat the disorders induced by damp-heat in the liver and the gall bladder. METHODS: In this study, the in vitro anti-herpes simplex virus type-1 (HSV-1) and type-2 (HSV-2) activity of the water extract of LDXGT was investigated. RESULTS: LDXGT water extract was shown to exhibit anti-HSV activity. The IC(50) values of LDXGT against HSV-1 and HSV-2 infections were 257.5 +/- 12.2 and 494.6 +/- 1.8 microg/ml, respectively. It had a CC(50) value of 4,077.2 +/- 2.4 microg/ml towards Vero cells and showed no cytotoxic effect at a concentration of 2,000 microg/ml or below. The prescription was also found to inactivate HSV-2 infectivity in a dose-, time- and temperature-dependent manner. CONCLUSIONS: In summary, the water extract of LDXGT was concluded to inhibit HSV-1 and HSV-2 infection at different magnitudes of potency, and our observations also suggested that the effect was likely mediated by directly inactivating the virus infectivity.


Assuntos
Antivirais/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 2/efeitos dos fármacos , Medicina Tradicional Chinesa/métodos , Animais , Antivirais/isolamento & purificação , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/isolamento & purificação , Herpesvirus Humano 1/fisiologia , Herpesvirus Humano 2/fisiologia , Fitoterapia/métodos , Células Vero
17.
Int J Pharm ; 346(1-2): 160-8, 2008 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-17689897

RESUMO

The purpose of this study was to develop quercetin-loaded nanoparticles (QUEN) by a nanoprecipitation technique with Eudragit E (EE) and polyvinyl alcohol (PVA) as carriers, and to evaluate the antioxidant effects of quercetin (QU) and of its nanoparticles. The novel QUEN systems were characterized by particle size and morphology, yield and encapsulation efficiency, differential scanning calorimetry (DSC), powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), (1)H nuclear magnetic resonance ((1)H NMR), and dissolution study. It was observed that the weight ratio of QU:EE:PVA at 1:10:10 carried a particle size of <85 nm, a particle distribution with polydispersity index <0.3, and its yield and encapsulation efficiency were over 99%. The results from XRD and DSC of the QUEN showed that the crystal of the drug might be converted to an amorphous state. The FT-IR and (1)H NMR demonstrated that QU formed intermolecular hydrogen bonding with carriers. The release of the drug from the QUEN was 74-fold higher compared with the pure drug. In addition, the antioxidant activity of the QUEN was more effective than pure QU on DPPH scavenging, anti-superoxide formation, superoxide anion scavenging, and anti-lipid peroxidation.


Assuntos
Antioxidantes/química , Nanopartículas/química , Quercetina/química , 1-Octanol/química , Animais , Antioxidantes/metabolismo , Compostos de Bifenilo/química , Varredura Diferencial de Calorimetria , Composição de Medicamentos , Suco Gástrico/química , Hidrazinas/química , Peroxidação de Lipídeos , Fígado/metabolismo , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura , Tamanho da Partícula , Picratos , Quercetina/metabolismo , Ratos , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Superóxidos/química , Água/química , Difração de Raios X , Xantina Oxidase/química
18.
Food Chem Toxicol ; 46(5): 1771-7, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18308443

RESUMO

Cuscuta chinensis is a commonly used traditional Chinese medicine to nourish the liver and kidney. Due to the poor water solubility of its major constituents such as flavonoids and lignans, its absorption upon oral administration could be limited. The purpose of the present study was to use the nanosuspension method to prepare C. chinensis nanoparticles (CN), and to compare the hepatoprotective and antioxidant effects of C. chinensis ethanolic extract (CE) and CN on acetaminophen-induced hepatotoxicity in rats. An oral dose of CE at 125 and 250 mg/kg and CN at 25 and 50mg/kg showed a significant hepatoprotective effect relatively to the same extent (P<0.05) by reducing levels of aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase. These biochemical assessments were supported by rat hepatic biopsy examinations. In addition, the antioxidant activities of CE and CN both significantly increased superoxide dismutase, catalase, glutathione peroxidase, and reduced malondialdehyde (P<0.05). Moreover, the results also indicated that the hepatoprotective and antioxidant effects of 50 mg/kg CN was effectively better than 125 mg/kg CE (P<0.05), and an oral dose of CN that is five times as less as CE could exhibit similar levels of outcomes. In conclusion, we suggest that the nanoparticles system can be applied to overcome other water poorly soluble herbal medicines and furthermore to decrease the treatment dosage.


Assuntos
Acetaminofen/antagonistas & inibidores , Acetaminofen/toxicidade , Analgésicos não Narcóticos/antagonistas & inibidores , Analgésicos não Narcóticos/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Cuscuta/química , Nanopartículas/química , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Animais , Antioxidantes/metabolismo , Aspartato Aminotransferases/sangue , Catalase/sangue , Doença Hepática Induzida por Substâncias e Drogas/patologia , Química Farmacêutica , Glutationa Peroxidase/sangue , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/patologia , Testes de Função Hepática , Masculino , Malondialdeído/sangue , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Ratos , Ratos Wistar , Superóxido Dismutase/sangue
19.
Food Chem ; 108(2): 455-62, 2008 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-26059122

RESUMO

Chinese herbs employed in traditional Chinese medicine (TCM) have been used for centuries in the practice of medicated diet and dietetic therapy. The seed of Cuscuta chinensis Lam. (Convolvulaceae), a commonly used traditional Chinese herb, is frequently added in Chinese cooking and preparation of refreshments, including porridge and alcoholic beverages, to nourish the human body. In the present study, we compared the antioxidant activities of water and ethanol extracts from the seeds C. chinensis and also of its different organic fractions, including n-hexane, ethyl acetate, n-butanol and organic water, by assessing their DPPH (1,1-diphenyl-2-picryl hydrazine) free radical-scavenging, superoxide anion scavenging, anti-superoxide anion formation and anti-lipid peroxidation abilities. The flavonol contents of all test samples were analyzed by high-performance liquid chromatography with an ultraviolet (HPLC-UV) detector. The results showed that there is a direct correlation of the flavonol content with the antioxidant activities from the extracts and fractions of C. chinensis. Moreover, the ethyl acetate fraction demonstrated significantly better and higher antioxidant effects, and also had a higher flavonol content than had the remaining samples (P<0.05). The water fractions, however, exhibited the weakest antioxidant activity, and had low concentrations of flavonols. Thus, we suggest that the ethanol extract of C. chinensis, but not its water extract, could be used as a dietary nutritional supplement to promote human health and prevent oxidation-related diseases, due to its antioxidant properties.

20.
Viruses ; 10(12)2018 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-30486350

RESUMO

Hepatitis C Virus (HCV) remains an important public health threat with approximately 170 million carriers worldwide who are at risk of developing hepatitis C-associated end-stage liver diseases. Despite improvement of HCV treatment using the novel direct-acting antivirals (DAAs) targeting viral replication, there is a lack of prophylactic measures for protection against HCV infection. Identifying novel antivirals such as those that target viral entry could help broaden the therapeutic arsenal against HCV. Herein, we investigated the anti-HCV activity of the methanolic extract from Rhizoma coptidis (RC), a widely used traditional Chinese medicine documented by the WHO and experimentally reported to possess several pharmacological functions including antiviral effects. Using the cell culture-derived HCV system, we demonstrated that RC dose-dependently inhibited HCV infection of Huh-7.5 cells at non-cytotoxic concentrations. In particular, RC blocked HCV attachment and entry/fusion into the host cells without exerting any significant effect on the cell-free viral particles or modulating key host cell entry factors to HCV. Moreover, RC robustly suppressed HCV pseudoparticles infection of Huh-7.5 cells and impeded infection by several HCV genotypes. Collectively, our results identified RC as a potent antagonist to HCV entry with potential pan-genotypic properties, which deserves further evaluation for use as an anti-HCV agent.


Assuntos
Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Hepacivirus/fisiologia , Hepatite C/virologia , Extratos Vegetais/farmacologia , Ranunculaceae/química , Internalização do Vírus/efeitos dos fármacos , Antivirais/química , Linhagem Celular , Genótipo , Humanos , Extratos Vegetais/química , Replicação Viral/efeitos dos fármacos
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