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1.
Antiviral Res ; 174: 104704, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31917237

RESUMO

AIMS: Deguelin, a natural compound derived from Mundulea sericea (Leguminosae) and some other plants exhibits an activity to inhibit autophagy, a cellular machinery required for hepatitis C virus (HCV) replication. This study aimed to illuminate the impact of deguelin on HCV replication and mechanism(s) involved. METHODS: HCV JFH-1-Huh7 infectious system was used for the investigation. Real time RT-PCR, Western blot, fluorescent microscopy assay were used to measure the expression levels of viral or cellular factors. Overexpression and silencing expression techniques were used to determine the role of key cellular factors. RESULTS: Deguelin treatment of Huh7 cells significantly inhibited HCV JFH-1 replication in a dose- and time-dependent manner. Deguelin treatment suppressed autophagy in Huh7 cells, evidenced by the decrease of LC3B-II levels, the conversion of LC3B-I to LC3B-II, and the formation of GFP-LC3 puncta as well as the increase of p62 level in deguelin-treated cells compared with control cells. HCV infection could induce autophagy which was also suppressed by deguelin treatment. Mechanism research reveals that deguelin inhibited expression of Beclin1, which is a key cellular factor for the initiation of the autophagosome formation in autophagy. Overexpression or silencing expression of Beclin1 in deguelin-treated Huh7 cells could weaken or enhance the inhibitory effect on autophagy by deguelin, respectively, and thus partially recover or further inhibit HCV replication correspondingly. CONCLUSIONS: Deguelin may serve as a novel anti-HCV compound via its inhibitory effect on autophagy, which warrants further investigation as a potential therapeutic agent for HCV infection.

2.
Cell Death Dis ; 9(9): 898, 2018 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-30185779

RESUMO

Both alcohol and hepatitis C virus (HCV) infection could induce cellular autophagy in liver cells, which is considered to be essential for productive HCV replication. However, whether alcohol-induced autophagy is involved in the pathogenesis of HCV infection is still poorly understood. Alcohol treatment could induce autophagy in Huh7 cells (a hepatoma cell line that supports HCV JFH-1 replication), evidenced by the increase of LC3B-II levels, the conversion of LC3B-I to LC3B-II, and the formation of GFP-LC3 puncta as well as the decrease of p62 level in alcohol-treated cells compared with control cells. Alcohol treatment also significantly increased PIASy (a member of the PIAS family) expression, which can act as a SUMO (small ubiquitin-like modifier protein) E3 ligase to regulate a broader range of cellular processes including autophagy. Overexpression or the silencing expression of PIASy in alcohol-treated Huh7 cells could increase or decrease autophagic activation caused by alcohol treatment, respectively, and thus affect HCV replication correspondingly. In the absence of alcohol, overexpression or silencing expression of PIASy increase or decrease the level of cellular autophagy, judged by the changes of LC3B-II and p62 levels in the presence or absence of chloroquine (CQ), a lysosome inhibitor. More importantly, in the presence of 3-methyladenine (3-MA), an inhibitor in the early stage of autophagy, the effects of overexpression or silencing expression of PIASy on HCV replication were largely blocked. Furthermore, PIASy could selectively drive the accumulation of SUMO1-conjugated proteins, along with upregulation of the expression of several important autophagy factors, including ATG7 and ATG5-ATG12. In conclusion, alcohol promotes HCV replication through activation of autophagy in Huh7 cells, which partly attributes to its induction of PIASy expression. PIASy-enhanced accumulation of SUMO1-conjugated proteins may contribute to its inducing effect of autophagy. Our findings provide a novel mechanism for the action of alcohol-promoting HCV replication in the context of cellular autophagy.


Assuntos
Autofagia/efeitos dos fármacos , Carcinoma Hepatocelular/genética , Etanol/farmacologia , Hepacivirus/genética , Proteínas de Ligação a Poli-ADP-Ribose/genética , Proteínas Inibidoras de STAT Ativados/genética , Regulação para Cima/efeitos dos fármacos , Replicação Viral/genética , Carcinoma Hepatocelular/virologia , Linhagem Celular Tumoral , Hepatite C/genética , Hepatite C/virologia , Hepatócitos/virologia , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/virologia , Proteínas Associadas aos Microtúbulos/genética , Ativação Transcricional/genética
3.
J Med Virol ; 90(6): 1112-1120, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29446489

RESUMO

Alcohol could compromise the anti-hepatitis C virus (HCV) function of interferon-alpha (IFN-α). However, little information is available about the effect of alcohol on interferon-lambda (IFN-λ, type III IFN), a novel candidate for development of therapy for HCV infection. Huh7 cells were infected with HCV JFH-1 virus, then treated with alcohol, and/or IFN-λ1. RT-PCR and Western blot were used to detect the levels of HCV and key cellular factors. Overexpression or silencing expression was performed to verify the role of key factors in alcohol-attenuated anti-HCV function of IFN-λ1. Alcohol treatment compromised anti-HCV effect of IFN-λ1 in HCV JFH-1-infected Huh7 cells, evidenced by the significantly increased levels of HCV RNA, and HCV core protein in alcohol-/IFN-λ1-treated cells compared to cells with IFN-λ1 treatment alone. Investigation of the mechanisms responsible for the alcohol action revealed that alcohol enhanced the expression of protein inhibitor of activated STAT (PIASy). Overexpression of PIASy compromised anti-HCV ability of IFN-λ1, whereas silencing expression of PIASy partly restored the alcohol-attenuated anti-HCV effect of IFN-λ1. More importantly, overexpression of PIASy significantly down-regulated the level of IFN-λ1-indcued phosphorylation of STAT1 (p-STAT1), an important adaptor in IFN-λ pathway, as well as reduced the expression of IFN-λ1-induced IFN-stimulated genes 56 (ISG56), and myxovirus resistance 1 (Mx1), two antiviral effectors in in IFN-λ pathway. These findings indicate that alcohol, through inducing the expression of negative regulator in IFN-λ pathway, inhibits IFN-λ-mediated anti-HCV action in human hepatic cells, which may lead to the poor efficacy of IFN-λ-based therapy against HCV infection.


Assuntos
Álcoois/metabolismo , Hepacivirus/imunologia , Hepatócitos/imunologia , Interleucinas/antagonistas & inibidores , Proteínas de Ligação a Poli-ADP-Ribose/biossíntese , Proteínas Inibidoras de STAT Ativados/biossíntese , Regulação para Cima , Western Blotting , Linhagem Celular , Perfilação da Expressão Gênica , Hepacivirus/crescimento & desenvolvimento , Hepatócitos/efeitos dos fármacos , Hepatócitos/virologia , Humanos , Interferons , RNA Viral/análise , Reação em Cadeia da Polimerase em Tempo Real , Proteínas do Core Viral/análise
4.
Appl Opt ; 56(4): C140-C144, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28158060

RESUMO

SiOxCy thin films were deposited by plasma polymerization. The stress of the deposited SiOxCy thin films can be modified by adjusting the beam current, the anode voltage, and the flow rate of hexamethyldisiloxane (HMDSO) gas and oxygen. Reducing the beam current or increasing the flow rate of HMDSO gas increased the linear/cage structure ratio and turned the stress of the SiOxCy thin films from compressive to tensile. The linear/cage structure ratio can be adjusted by changing the composite parameter, W[FM]c/[FM]m, to control the stress of the deposited plasma polymer films. Multilayers of TiO2/SiO2/TiO2 were coated on a SiOxCy plasma polymer film herein, reducing their stress by 70% from 0.06 to 0.018 GPa. The refractive index is 1.55, and the absorption coefficient is less than 10-4 at 550 nm of the SiOxCy films. Superior optical performances of SiOxCy thin films make their use in optical thin films.

5.
Zhongguo Zhong Yao Za Zhi ; 41(17): 3232-3238, 2016 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-28920375

RESUMO

To prepare tanshinone ⅡA loaded nanostructured lipid carrier (Tan ⅡA-NLC), and study its in vitro transdermal permeation characteristics. The Tan ⅡA-NLC was prepared by high pressure homogenization technology and optimized by Box-Behnken design-response surface method, and it was characterized in terms of morphology, particle size, zeta potention, et al. The transdermal permeation of Tan ⅡA-NLC was evaluated by using Franz diffusion cells. The results showed that, the optimal formulation was as follows: drug/lipid materials ratio 88, GMS/MCT ratio 2, emulsifier concentration 1%, average particle size (182±14) nm, polydispersity index PDI (0.190 6±0.024 5), zeta potential (-27.8± 5.4) mV, encapsulation efficiency EE (86.44%±9.26%) and drug loading DL (0.98%±0.18%), respectively. The in vitro transdermal permeation results showed that as compared with Tan ⅡA solution, Tan ⅡA-NLC had lower transdermal permeation amount after applying drug for 24 h, but its retention in the epidermis was 3.18 times that of solution. These results indicated that the prepared Tan ⅡA-NLC could effectively increase the regention of Tan ⅡA in the epidermis, and had a broad application prospect.


Assuntos
/administração & dosagem , Portadores de Fármacos , Lipídeos , Nanopartículas , Absorção Cutânea , Administração Cutânea , Técnicas In Vitro , Tamanho da Partícula
6.
Chin J Nat Med ; 14(10): 757-768, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28236405

RESUMO

Herpetospermum caudigerum lignans (HTL), one of the potential drugs with anti-hepatitis B virus and hepatoprotective effects, has limited clinical applications because of poor aqueous solubility and low bioavailability. Both herpetrione (HPE) and herpetin (HPN) are the most abundant ingredients in HTL and exhibit weak acidity. The purpose of the present study was to produce dried preparations of HTL (composed of HPE and HPN) nanosuspensions (HTL-NS) with high redispersibility using lyophilization technology. The HTL-NS was prepared by utilizing precipitation-combined homogenization technology based on acid-base neutralization reactions, and critical formulation and process parameters affecting the characteristics of HTL-NS were optimized. The resultant products were characterized by particle size analysis, SEM, XRD, stability, solubility, dissolution and in vivo bioavailability. HTL-NS showed near-spherical-shaped morphology and the size was 243 nm with a narrow PDI value of 0.187. The dried preparations with a relatively large particle size of 286 nm and a PDI of 0.215 were achieved by using 4% (W/V) mannitol as cryoprotectants, and had a better stability at 4 or 25 °C for 2 months, compared to HTL-NS. In the in vitro test, the dried preparations showed markedly increased solubility and dissolution velocity. Besides, in the in vivo evaluation, it exhibited significant increases in AUC0-t, Cmax,MRT and a decrease in Tmax, compared to the raw drug. In conclusion, our results provide a basis for the development of a drug delivery system for poorly water-soluble ingredients with pH-dependent solubility.


Assuntos
Química Farmacêutica/métodos , Lignanas/química , Lignanas/farmacocinética , Nanopartículas/química , Animais , Disponibilidade Biológica , Linhagem Celular , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Humanos , Lignanas/administração & dosagem , Masculino , Nanopartículas/administração & dosagem , Tamanho da Partícula , Ratos , Ratos Wistar , Solubilidade , Difração de Raios X
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