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1.
Int J Mol Sci ; 21(19)2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32998270

RESUMO

Immune modulation is a very modern medical field for targeting viral infections. In the race to develop the best immune modulator against viruses, curcumin, as a natural product, is inexpensive, without side effects, and can stimulate very well certain areas of the human immune system. As a bright yellow component of turmeric spice, curcumin has been the subject of thousands of scientific and clinical studies in recent decades to prove its powerful antioxidant properties and anticancer effects. Curcumin has been shown to influence inter- and intracellular signaling pathways, with direct effects on gene expression of the antioxidant proteins and those that regulate the immunity. Experimental studies have shown that curcumin modulates several enzyme systems, reduces nitrosative stress, increases the antioxidant capacity, and decreases the lipid peroxidation, protecting against fatty liver pathogenesis and fibrotic changes. Hepatitis B virus (HBV) affects millions of people worldwide, having sometimes a dramatic evolution to chronic aggressive infection, cirrhosis, and hepatocellular carcinoma. All up-to-date treatments are limited, there is still a gap in the scientific knowledge, and a sterilization cure may not yet be possible with the removal of both covalently closed circular DNA (cccDNA) and the embedded HBV DNA. With a maximum light absorption at 420 nm, the cytotoxicity of curcumin as photosensitizer could be expanded by the intravenous blue laser blood irradiation (IVBLBI) or photobiomodulation in patients with chronic hepatitis B infection, Hepatitis B e-antigen (HBeAg)-positive, noncirrhotic, but nonresponsive to classical therapy. Photobiomodulation increases DNA repair by the biosynthesis of complex molecules with antioxidant properties, the outset of repairing enzyme systems and new phospholipids for regenerating the cell membranes. UltraBioavailable Curcumin and blue laser photobiomodulation could suppress the virus and control better the disease by reducing inflammation/fibrosis and stopping the progression of chronic hepatitis, reversing fibrosis, and diminishing the progression of cirrhosis, and decreasing the incidence of hepatocellular carcinoma. Photodynamic therapy with blue light and curcumin opens new avenues for the effective prevention and cure of chronic liver infections and hepatocellular carcinoma. Blue laser light and UltraBioavailable Curcumin could be a new valuable alternative for medical applications in chronic B viral hepatitis and hepatocarcinoma, saving millions of lives.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Carcinoma Hepatocelular/radioterapia , Curcumina/uso terapêutico , Hepatite B Crônica/radioterapia , Cirrose Hepática/radioterapia , Neoplasias Hepáticas/radioterapia , Terapia com Luz de Baixa Intensidade/métodos , Antioxidantes/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/virologia , Reparo do DNA/efeitos da radiação , DNA Circular/antagonistas & inibidores , DNA Circular/genética , DNA Circular/metabolismo , DNA Viral/antagonistas & inibidores , DNA Viral/genética , DNA Viral/metabolismo , Antígenos E da Hepatite B/genética , Antígenos E da Hepatite B/imunologia , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/crescimento & desenvolvimento , Vírus da Hepatite B/patogenicidade , Vírus da Hepatite B/efeitos da radiação , Hepatite B Crônica/complicações , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/virologia , Humanos , Fatores Imunológicos/uso terapêutico , Fígado/efeitos dos fármacos , Fígado/imunologia , Fígado/patologia , Fígado/efeitos da radiação , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/etiologia , Cirrose Hepática/virologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/virologia , Fármacos Fotossensibilizantes/uso terapêutico
2.
Artigo em Inglês | MEDLINE | ID: mdl-30224536

RESUMO

Currently available therapies for chronic hepatitis B virus (HBV) infection can efficiently reduce viremia but induce hepatitis B surface antigen (HBsAg) loss in very few patients; also, these therapies do not greatly affect the viral covalently closed circular DNA (cccDNA). To discover new agents with complementary anti-HBV effects, we performed a drug repurposing screen of 1,018 Food and Drug Administration (FDA)-approved compounds using HBV-infected primary human hepatocytes (PHH). Several compounds belonging to the family of retinoic acid receptor (RAR) agonists were identified that reduced HBsAg levels in a dose-dependent manner without significant cytotoxicity. Among them, tazarotene exhibited the most potent anti-HBV effect, with a half-maximal inhibitory concentration (IC50) for HBsAg of less than 30 nM in PHH. The inhibitory effect was also observed in HBV-infected differentiated HepaRG (dHepaRG) models, but not in HepG2.215 cells, and HBV genotypes A to D were similarly inhibited. Tazarotene was further demonstrated to repress HBV cccDNA transcription, as determined by the levels of HBV cccDNA and RNAs and the activation of HBV promoters. Moreover, RNA sequence analysis showed that tazarotene did not induce an interferon response but altered the expression of a number of genes associated with RAR and metabolic pathways. Inhibition of RARß, but not RARα, by a specific antagonist significantly attenuated the anti-HBV activity of tazarotene, suggesting that tazarotene inhibits HBV in part through RARß. Finally, a synergistic effect of tazarotene and entecavir on HBV DNA levels was observed. Therefore, RAR agonists as represented by tazarotene were identified as potential novel anti-HBV agents.


Assuntos
Antivirais/farmacologia , Guanina/análogos & derivados , Vírus da Hepatite B/efeitos dos fármacos , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Ácidos Nicotínicos/farmacologia , Receptores do Ácido Retinoico/genética , Acitretina/farmacologia , Adapaleno/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fármacos Dermatológicos/farmacologia , Reposicionamento de Medicamentos , Sinergismo Farmacológico , Expressão Gênica , Guanina/farmacologia , Células Hep G2 , Antígenos de Superfície da Hepatite B/genética , Antígenos de Superfície da Hepatite B/metabolismo , Antígenos E da Hepatite B/genética , Antígenos E da Hepatite B/metabolismo , Vírus da Hepatite B/genética , Vírus da Hepatite B/crescimento & desenvolvimento , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/virologia , Ensaios de Triagem em Larga Escala , Interações Hospedeiro-Patógeno/genética , Humanos , Ceratolíticos/farmacologia , Receptores do Ácido Retinoico/agonistas , Receptores do Ácido Retinoico/metabolismo , Transcrição Gênica/efeitos dos fármacos , Tretinoína/farmacologia , Replicação Viral/efeitos dos fármacos
3.
Molecules ; 20(3): 5137-51, 2015 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-25808155

RESUMO

UNLABELLED: In order to improve the bioavailability levels of polyprenols (derived from ginkgo leaves (GBP)) in the human body, a GBP nanoemulsion was prepared, and its antiviral activity was evaluated against influenza A H3N2 and hepatitis B virus in vitro. METHODS: A GBP nanoemulsion was prepared by inversed-phase emulsification (IPE). Next, we investigated the antiviral activity of the GBP nanoemulsion on influenza A H3N2 and hepatitis B virus in vitro by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenlytetrezolium bromide) method. ELISA and the fluorescent quantitative PCR method were used to measure the content of HBsAg, HBeAg and DNA virus in human samples. RESULTS: The GBP nanoemulsion exhibited uniformity at an average particle size 97 nm with a hydrophilic-lipophilic balance (HLB) of 9.5. GBP is non-toxic to normal cells, hepatitis B virus DNA, hepatitis B virus antigen and HepG2215. Furthermore, GBP could reach a 70% virucidal activity and a 74.9% protection rate (*** p < 0.001) on MDCK cells infected with H3N2 virus at a high concentration of 100 µg/mL. GBP had a good inhibition rate on HBsAg (52.11%, ** p < 0.01) at 50 µg/mL and Day 9 of incubation, and a 67.32% inhibition effect on HBeAg at a high concentration of 100 µg/mL and Day 9. GBP had good inhibition on HBV DNA with CT 18.6 and lower copies (** p < 0.01) at a middle concentration of 12.5 to 25 µg/mL. CONCLUSIONS: The GBP nanoemulsion was very stable and non-toxic and had very strong antiviral activity against influenza A H3N2 and hepatitis B virus in vitro. The inhibitory effects and reactive mechanisms were similar to the drug, 3TC; by lengthening the incubation time and increasing the drug concentration, GBP has promising potential as an antiviral drug.


Assuntos
Antivirais/química , Antivirais/farmacologia , Ginkgo biloba/química , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Terpenos/química , Terpenos/farmacologia , Animais , Linhagem Celular Tumoral , DNA Viral/efeitos dos fármacos , DNA Viral/genética , Cães , Antígenos de Superfície da Hepatite B/efeitos dos fármacos , Antígenos de Superfície da Hepatite B/genética , Antígenos E da Hepatite B/efeitos dos fármacos , Antígenos E da Hepatite B/genética , Vírus da Hepatite B/genética , Humanos , Técnicas In Vitro , Vírus da Influenza A Subtipo H3N2/genética , Células Madin Darby de Rim Canino , Tamanho da Partícula , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química
4.
World J Gastroenterol ; 12(35): 5721-5, 2006 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-17007029

RESUMO

AIM: To explore the anti-hepatitis B virus (HBV) effects of Boehmeria nivea (B. nivea) root extract (BNE) by using the HepG2 2.2.15 cell model system. METHODS: Hepatitis B surface antigen (HBsAg), hepatitis B virus e antigen (HBeAg), and HBV DNA were measured by using ELISA and real-time PCR, respectively. Viral DNA replication and RNA expression were determined by using Southern and Northern blot, respectively. RESULTS: In HepG2 2.2.15 cells, HBeAg (60%, P < 0.01) and particle-associated HBV DNA (> 99%, P < 0.01) secretion into supernatant were significantly inhibited by BNE at a dose of 100 mg/L, whereas the HBsAg was not inhibited. With different doses of BNE, the reduced HBeAg was correlated with the inhibition of HBV DNA. The anti-HBV effect of BNE was not caused by its cytotoxicity to cells or inhibition of viral DNA replication and RNA expression. CONCLUSION: BNE could effectively reduce the HBV production and its anti-HBV machinery might differ from the nucleoside analogues.


Assuntos
Boehmeria/química , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/virologia , Vírus da Hepatite B/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/virologia , Antivirais/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Citotoxinas/farmacologia , Replicação do DNA/efeitos dos fármacos , DNA Viral/genética , DNA Viral/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Antígenos de Superfície da Hepatite B/genética , Antígenos de Superfície da Hepatite B/metabolismo , Antígenos E da Hepatite B/genética , Antígenos E da Hepatite B/metabolismo , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Raízes de Plantas/química , RNA Viral/genética , RNA Viral/metabolismo , Transcrição Gênica/efeitos dos fármacos
5.
Gastroenterology ; 125(1): 9-18, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12851866

RESUMO

BACKGROUND & AIMS: Hepatitis B virus (HBV) causes acute and chronic infections that may result in severe liver diseases. Animal models to study new treatment options in vivo have several drawbacks. Therefore, we were interested to establish a new small animal model in which HBV replication and especially new treatment options can be studied easily. METHODS: Naked DNA of an HBV replication competent vector was transferred via tail vein into NMRI mice. HBV replication was studied in serum and liver of the animals. HBV replication was modulated by treatment through siRNA and nucleoside analogues. RESULTS: Tail vein transfer of a HBV replication competent construct resulted in expression of HBV-specific transcripts in the liver, and up to 10% of hepatocytes became HBc- and HBsAg-positive. HBeAg, HBsAg, and viral DNA could be detected in the serum of the animals, followed by the induction of HBV-specific cellular immune responses. Nucleoside treatment of the mice resulted in reduced polymerase activity in the liver. Additionally, siRNA transfer in the animals led to a significant reduction of HBsAg and/or eventually HBeAg expression, which was dependent on the localization of the complementary sequence in the HBV genome. CONCLUSIONS: We have established a mouse model to study HBV replication and to investigate new and existing treatment approaches in vivo. Interestingly, siRNA seems a promising innovative treatment option to inhibit specifically HBV replication in vivo.


Assuntos
Terapia Genética/métodos , Vírus da Hepatite B/crescimento & desenvolvimento , Hepatite B/tratamento farmacológico , Organofosfonatos , RNA Interferente Pequeno/farmacologia , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Capsídeo , Terapia Combinada , Modelos Animais de Doenças , Regulação Viral da Expressão Gênica , Antígenos de Superfície da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/genética , Antígenos E da Hepatite B/sangue , Antígenos E da Hepatite B/genética , Vírus da Hepatite B/genética , Lamivudina/farmacologia , Fígado/virologia , Masculino , Camundongos , Camundongos Endogâmicos , Inibidores da Transcriptase Reversa/farmacologia , Organismos Livres de Patógenos Específicos , Replicação Viral
6.
J Immunol ; 168(10): 4951-9, 2002 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-11994446

RESUMO

Particulate hepatitis B core Ag (C protein) (HBcAg) and soluble hepatitis B precore Ag (E protein) (HBeAg) of the hepatitis B virus share >70% of their amino acid sequence and most T and B cell-defined epitopes. When injected at low doses into mice, HBcAg particles prime Th1 immunity while HBeAg protein primes Th2 immunity. HBcAg contains 5-20 ng RNA/microg protein while nucleotide binding to HBeAg is not detectable. Deletion of the C-terminal arginine-rich domain of HBcAg generates HBcAg-144 or HBcAg-149 particles (in which >98% of RNA binding is lost) that prime Th2-biased immunity. HBcAg particles, but not truncated HBcAg-144 or -149 particles stimulate IL-12 p70 release by dendritic cells and IFN-gamma release by nonimmune spleen cells. The injection of HBeAg protein or HBcAg-149 particles into mice primes Th1 immunity only when high doses of RNA (i.e., 20-100 microg/mouse) are codelivered with the Ag. Particle-incorporated RNA has thus a 1000-fold higher potency as a Th1-inducing adjuvant than free RNA mixed to a protein Ag. Disrupting the particulate structure of HBcAg releases RNA and abolishes its Th1 immunity inducing potency. Using DNA vaccines delivered intradermally with the gene gun, inoculation of 1 microg HBcAg-encoding pCI/C plasmid DNA primes Th1 immunity while inoculation of 1 microg HBeAg-encoding pCI/E plasmid DNA or HBcAg-149-encoding pCI/C-149 plasmid DNA primes Th2 immunity. Expression data show eukaryotic RNA associated with HBcAg, but not HBeAg, expressed by the DNA vaccine. Hence, codelivery of an efficient, intrinsic adjuvant (i.e., nanogram amounts of prokaryotic or eukaryotic RNA bound to arginine-rich sequences) by HBcAg nucleocapsids facilitates priming of anti-viral Th1 immunity.


Assuntos
Arginina/metabolismo , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Antígenos do Núcleo do Vírus da Hepatite B/metabolismo , Proteínas/imunologia , Proteínas/metabolismo , RNA Viral/imunologia , Células Th1/imunologia , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/genética , Adjuvantes Imunológicos/metabolismo , Animais , Sítios de Ligação/genética , Sítios de Ligação/imunologia , DNA Recombinante/administração & dosagem , DNA Recombinante/imunologia , Escherichia coli/genética , Escherichia coli/imunologia , Feminino , Antígenos do Núcleo do Vírus da Hepatite B/administração & dosagem , Antígenos do Núcleo do Vírus da Hepatite B/genética , Antígenos E da Hepatite B/administração & dosagem , Antígenos E da Hepatite B/biossíntese , Antígenos E da Hepatite B/genética , Antígenos E da Hepatite B/imunologia , Imunidade Ativa/genética , Injeções Intramusculares , Interferon gama/metabolismo , Interleucina-12/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Fatores de Crescimento Neural , Estrutura Terciária de Proteína/genética , RNA Bacteriano/administração & dosagem , RNA Bacteriano/genética , RNA Bacteriano/imunologia , RNA Bacteriano/metabolismo , RNA Viral/administração & dosagem , RNA Viral/genética , RNA Viral/metabolismo , Células Th1/metabolismo , Células Th1/virologia , Transformação Bacteriana , Células Tumorais Cultivadas , Vacinas de DNA/administração & dosagem , Vacinas de DNA/imunologia
7.
Artigo em Chinês | MEDLINE | ID: mdl-15617349

RESUMO

Seven preparations of different species of Chinese herb Phyllarthus with different formulations and additives were studied for their ability to inhibit hepatitis B virus DNA replication, that is the HBsAg and HBeAg expression in a HBV DNA-transfected cell line (2.2.15 cell). The results showed that all the drugs were effectively against HBV replication in vitro. Capsule 1 and tuo cha zhen zhu cao were found to be the most potent anti-HBV extracts of those examined. Both extracts decreased HBaAg expression by nearly 100% at the concentration of 500 mg/L without toxicity on cell growth. Southern blot showed that Capsule 1 inhibited HBV DNA replication in a dose-dependent manner. We observed further, that under similar dosage the drug inhibition to HBsAg and HBeAg expression was lower than that to HBV DNA replication, suggesting that the production of progeny virus particles not only were inhibited at the level of HBV DNA synthesis, but also was affected probably at the level of translation of viral mRNA.


Assuntos
Regulação para Baixo , Medicamentos de Ervas Chinesas/farmacologia , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B/tratamento farmacológico , Phyllanthus/química , Replicação Viral/efeitos dos fármacos , Linhagem Celular , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Hepatite B/virologia , Antígenos de Superfície da Hepatite B/genética , Antígenos de Superfície da Hepatite B/metabolismo , Antígenos E da Hepatite B/genética , Antígenos E da Hepatite B/metabolismo , Vírus da Hepatite B/genética , Vírus da Hepatite B/metabolismo , Humanos
8.
Antiviral Res ; 27(1-2): 99-109, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7486962

RESUMO

We have examined the antiviral activity of the crude extract prepared from the root of Saussurea lappa Clarks, a Chinese medicinal herb which is widely used for many illnesses including cancer. Two active components, costunolide and dehydrocostus lactone, were identified which show strong suppressive effect on the expression of the hepatitis B surface antigen (HBsAg) in human hepatoma Hep3B cells, but have little effect on the viability of the cells. Both costunolide and dehydrocostus lactone suppress the HBsAg production by Hep3B cells in a dose-dependent manner with IC50s of 1.0 and 2.0 microM, respectively. Northern blotting analysis shows that the suppression of HBsAg gene expression by both costunolide and dehydrocostus lactone were mainly at the mRNA level. Furthermore, the suppressive effect of costunolide and dehydrocostus lactone on HBsAg and hepatitis B e antigen (HBeAg), a marker for hepatitis B viral genome replication in human liver cells, was also observed in another human hepatoma cell line HepA2 which was derived from HepG2 cells by transfecting a tandemly repeat hepatitis B virus (HBV) DNA. Similarly, the mRNA of HBsAg in HepA2 cells was also suppressed by these two compounds. Our findings suggest that costunolide and dehydrocostus lactone may have potential to develop as specific anti-HBV drugs in the future.


Assuntos
Antivirais/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Antígenos de Superfície da Hepatite B/metabolismo , Lactonas/farmacologia , Sesquiterpenos/farmacologia , Carcinoma Hepatocelular , Medicamentos de Ervas Chinesas/química , Antígenos de Superfície da Hepatite B/genética , Antígenos E da Hepatite B/genética , Antígenos E da Hepatite B/metabolismo , Humanos , Lactonas/química , Estrutura Molecular , Raízes de Plantas/química , RNA Mensageiro/metabolismo , RNA Viral/metabolismo , Sesquiterpenos/química , Células Tumorais Cultivadas
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