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This study aims to investigate the inhibitory effect of Pien Tze Huang(PZH) on enterovirus 71(EV71). To be speci-fic, chemiluminescence method was adopted to evaluate the toxicity of PZH to African green monkey kidney(Vero) cells and human rhabdomyosarcoma(RD) cells, and cytopathic effect(CPE) method to assess the inhibition on EV71-GFP reporter virus and EV71 C4 wild-type virus. The results showed that PZH had low cytotoxicity to Vero cells and RD cells, with the half-maximal cytotoxic concentration(CC_(50)) of about 0.691 3-0.879 2 mg·mL~(-1) for the two. In addition, PZH can effectively inhibit the replication of EV71 within the non-cytotoxic concentration range, and dose-dependently alleviate the cytopathic changes caused by virus infection, with the half-maximal effective concentration(EC_(50)) of 0.009 2-0.106 3 mg·mL~(-1). On the basis of the above results, the green fluorescent protein(GFP), indirect immunofluorescence assay(IFA), and median tissue culture infective dose(TCID_(50)) were employed to assess and verify the anti-EV71-GFP and anti-EV71 C4 activity of PZH. The results demonstrated that PZH can dose-dependently lower the expression of GFP by EV71-GFP and structural protein VP-1 by EV71 C4 and decrease the production of progeny infectious viruses. The EC_(50) of PZH for EV71-GFP and EV71 C4 was about 0.006 0-0.006 2 mg·mL~(-1) and 0.006 6-0.025 6 mg·mL~(-1), respectively. This study suggested that PZH may exert antiviral activity by acting on EV71 and interfering with the expression of VP-1. At the moment, there is still a lack of specific anti-EV71 drugs. This study proposed a new idea for the symptomatic treatment of EV71 infections such as hand-foot-mouth disease and verified an effective drug for the treatment of EV71 infections.
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Animals , Chlorocebus aethiops , Drugs, Chinese Herbal/pharmacology , Enterovirus A, Human/physiology , Hand, Foot and Mouth Disease , Vero CellsABSTRACT
@#Innate immunity plays an important role in viral keratitis. Recently, it has been found that surfactant proteins(SP)A and D in the innate immune system are essential in viral keratitis. SP can inhibit virus adhesion to host cells and further promote phagocytosis of virus through high affinity for virus ligands. In order to ensure the normal function of tissues in the early stage of virus infection, SP regulates immune cells to maintain a non-inflammatory state. However, when pathogen invasion increases, SP promoted inflammation and increased the immune cells to kill the pathogens. SP-A and SP-D could be expressed in cornea, conjunctiva. To play the role of anti-adenovirus, herpes simplex virus, cytomegalovirus and other major eye pathogenic viruses, SP-A and SP-D combine with the virus to prevent entry into cells, promote phagocytosis, and directly kill the virus. SP-A and SP-D may be used as clinical diagnostic tools for viral infection. In the future, recombinant SP is expected to be used as an important means for the treatment of viral keratitis. Here, we review the innate immune function of SP-A and SP-D in ocular viral infection.
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Objective:To investigate the impact of low level viremia (LLV) on the prognosis of human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) patients received anti-retroviral therapy (ART).Methods:From January to December 2015, the HIV/AIDS patients with LLV received ART over one year were recruited in Guangzhou Eighth People′s Hospital, Guangzhou Medical University (LLV group). Patients with viral load (VL) less than 50 copies/mL were matched at ratio of 1∶1 according to gender, age and the transmission route were included in the control group (suppression group). The LLV group was divided into three subgroups according to VL (LLV-1 subgroup was 50-200 copies/mL, LLV-2 subgroup was 201-400 copies/mL, and LLV-3 subgroup was 401-1 000 copies/mL). The influence of LLV on the antiviral response during the following three years was investigated.The Wilcoxon signed rank test, Kruskal-Wallis test and chi-square test were used for statistical analysis.Results:One hundred and thirty-seven patients were enrolled in the LLV group, of whom 111 were males and 26 were females, with age of (39.5±13.5) years old. At the same time, 137 patients were included in the suppression group. There were 93 cases in LLV-1 subgroup, 25 cases in LLV-2 subgroup and 19 cases in LLV-3 subgroup. There were no significant differences in the CD4 + T lymphocyte counts and CD4 + /CD8 + T lymphocyte counts ratios between LLV group and suppression group before ART (both P>0.05). During the three-year follow-up, the cumulative number of viral failures in LLV group (7.3%(10/137)) was significantly higher than that in the suppression group (1.5%(2/137)) ( χ2=5.578, P=0.018). Virological failure occurred in eight patients (8.6%) in the LLV-1 subgroup, two patients (8.0%) in the LLV-2 subgroup, and no patients in the LLV-3 subgroup. There was no statistical significance in the incidence of virological failure among all the subgroups ( P>0.05). At one, two, three years follow-up, the CD4 + T lymphocyte counts increased in both LLV group and suppression group without statistical differences (all P>0.05), and the CD4 + /CD8 + T lymphocyte counts ratios in each LLV group were lower than that in the suppression group ( Z=-3.183, -2.094 and -2.312, respectively, all P<0.05). At one, two, three years follow-up, There were no significant differences in CD4 + /CD8 + T lymphocyte counts ratios among the LLV-1, LLV-2 and LLV-3 subgroups (all P>0.05). Conclusion:HIV/AIDS patients with LLV having received ART over one year are more likely to develop virological failure and delay the recovery of immune function, which requires early relevant interventions.
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Compound houttuynia mixture belongs to OTC class A medicine, which is made from Houttuynia cordata, Scutellaria baicalensis, Radix Isatidis, Forsythia, and Lonicera. As a kind of compound preparation of traditional Chinese medicine, houttuynia cordata mixture has extensive pharmacological effects, for example, clearing away heat and detoxifying, thus it is used for the sore throat, acute pharyngitis, and tonsillitis with wind-heat syndrome. In this study, the antiviral activity against influenza viruses and the primary mechanism of compound houttuynia mixture was evaluated. The antiviral effect of compound houttuynia mixture was determined by cytopathic effects (CPE), Western blot, quantitive reverse transcription PCR (qRT-PCR), and virus titer assays. The effect of houttuynia mixture on the replication cycle of influenza virus was evaluated by time-of-addition assay. In conclusion, the results showed that the compound houttuynia mixture had a broad-spectrum effect against influenza virus, including the international common influenza virus strains, the drug-resistant strains and the highly pathogenic avian influenza viruses H5N1 and H7N9. It mainly impairs the early stage of the viral replication.
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ABSTRACT Zika virus (ZIKV) infection during pregnancy is associated with a congenital syndrome. Although the virus can be detected in human placental tissue and sexual transmission has been verified, it is not clear how the virus reaches the fetus. Despite the emerging severity caused by ZIKV infection, no specific prophylactic and/or therapeutic treatment is available. The aim of the present study was to evaluate the effectiveness antiviral of nitazoxanide (NTZ) in two important congenital transmission targets: (i) a primary culture of human placental chorionic cells, and (ii) human cervical epithelial cells (C33-A) infected with Brazilian ZIKV strain. Initially, NTZ activity was screened in ZIKV infected Vero cells under different treatment regimens with non-toxic drug concentrations for 48 h. Antiviral effect was found only when the treatment was carried out after the viral inoculum. A strong effect against the dengue virus serotype 2 (DENV-2) was also observed suggesting the possibility of treating other Flaviviruses. Additionally, it was shown that the treatment did not reduce the production of infectious viruses in insect cells (C6/36) infected with ZIKV, indicating that the activity of this drug is also related to host factors. Importantly, we demonstrated that NTZ treatment in chorionic and cervical cells caused a reduction of infected cells in a dose-dependent manner and decreased viral loads in up to 2 logs. Pre-clinical in vitro testing evidenced excellent therapeutic response of infected chorionic and cervical cells and point to future NTZ activity investigation in ZIKV congenital transmission models with the perspective of possible repurposing of NTZ to treat Zika fever, especially in pregnant women.
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Animals , Female , Humans , Pregnancy , Zika Virus , Zika Virus Infection , Thiazoles , Virus Replication , Vero Cells , Brazil , Chlorocebus aethiops , Zika Virus Infection/drug therapy , Nitro CompoundsABSTRACT
The main chemical components of Artemisiae Scopariae Herba (ASH) include coumarins, flavonoids, organic acids, essential oils, and so on. Except for the traditional actions of clearing and draining dampness-heat, and disinhibiting gallbladder and anti-icteric, ASH has multiple pharmacological activities, such as antipyretic, analgesic, anti-inflammatory, antiviral, antitumor, hypotensive, hypolipidemic, anti-osteoporotic, neuroprotective, metabolic regulation effects, as well as prevention of Alzheimer’s disease, whose mechanism of actions are complex. This article reviews pharmacological actions and the corresponding mechanism of ASH, which can provide reference for the research, development and clinical application of ASH and its preparations.
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Abstract Probiotic bacteria are microorganisms beneficial to human health, useful to improving biological conditions. Thanks to probiotic bacteria the symptoms of viral infections can be alleviated. Different mechanisms whereby probiotic bacteria exert they antiviral effect have been proposed. The aim of this study was to determine whether probiotic bacteria extracts bind to receptors of host cells susceptible of rotavirus (RV) infection. To accomplish this objective, four probiotic bacterial strains of Lactobacillus spp. and Bifidobacterium spp. were tested. Probiotic extracts were obtained after bacterial growth, cell lysis and centrifugation. Obtained probiotic extracts were used in assays to interfere with adhesion and penetration of a RV strain in the mammal cell line MA104. Furthermore, the interaction between probiotic extracts and MA104 cell receptors was evaluated by co-immunoprecipitation assays using anti-β3-integrins and anti-Hsc70 antibodies. All four probiotic, protein-rich, extracts reduced RV infections in MA104 cells, suggesting a successful antiviral activity mediated by these probiotic extracts. All probiotic extracts significantly exerted their antiviral activity by interfering with RV adhesion on MA104 cell receptors, with proteins in probiotic extracts competitively interacting with cell surface receptors necessary to RV infection. Co-immunoprecipitation assay results showed that proteins in probiotic extracts were able to bind to β3-integrinsand Hsc70, which are two cellular receptors required to viral infection. The most significant contribution of this study is an insight into the mechanisms of probiotic antiviral activity, thus expanding current probiotics fundamental knowledge.
Resumen Las bacterias probióticas son microorganismos con efectos positivos en la salud humana, gracias a las bacterias probióticas los síntomas de infecciones virales pueden mitigarse. Al respecto, varios mecanismos antivirales de las bacterias probióticas han sido propuestos. El propósito de este estudio fue determinar, de manera experimental, si extractos de bacterias probióticas reducen la infección rotavírica al interferir con la unión entre el rotavirus y sus receptores celulares blanco. Extractos de cuatro cepas probióticas de Lactobacillus spp. y Bifidobacterium spp. fueron obtenidos a partir de cultivos bacterianos lisados y centrifugados. Cada uno de los extractos fue usado en experimentos para determinar si estos interfieren con la adhesión y penetración del rotavirus en células de mamífero MA104. Además, la interacción entre extractos probióticos y receptores de las células MA104 fue evaluada con ensayos de co-inmunoprecipitación, usando anticuerpos anti-integrina β3 y anti-Hsc70. Se observó que los cuatro extractos probióticos, ricos en proteínas, redujeron significativamente la infección de rotavirus en las células MA104. También se estableció que la que la actividad antiviral de los extractos probióticos es mediada por la interacción competitiva de sus proteínas con los receptores integrina β3 y Hsc70 de las células MA104, necesarios para iniciar la infección por rotavirus. Estos hallazgos constituyen un aporte al conocimiento de los mecanismos básicos de acción antiviral de las bacterias probióticas.
Resumo Bactérias probióticas são microrganismos com efeitos positivos na saúde humana, úteis na melhora de certas condições biológicas. Gracas a bactérias probióticas os sintomas de uma infecção viral podem ser aliviados. Diferentes mecanismos pelos quais as bactérias probióticas exercem seus efeitos antivirales têm sido propostos. O objetivo de este estudo foi determinar se extratos de bactérias probióticas reduzem a infecção de rotavírus (RV) ao interferir com a união entre o RV e seus receptores celulares alvo. Quatro cepas probióticas de Lactobacillus spp. e Bifidobacterium spp. foram testadas. Os extratos probióticos foram obtidos após o crescimento bacteriano, lise celular e centrifugação. Os extratos probióticos obtidos foram utilizados em ensaios para determinar se interferem com a adesão e penetração de uma cepa de RV em células de mamífero MA104. Adicionalmente, a interação entre os extratos probióticos e os receptores das células MA104 foi avaliada por ensaios de co-imunoprecipitação usando anticorpos anti-integrina β3 e anti- Hsc70. Os quatro extratos probióticos, ricos em proteínas, reduziram as infecções por RV em células MA104, sugerindo uma atividade antiviral mediada por estes extratos. Todos os extratos interferiram na adesão do RV aos receptores de células MA104, sendo que as proteínas presentes nos extratos mostraram uma interação competitiva com os receptores integrina β3 e Hsc70 das células MA104, necessários para iniciar a infecção por RV. Estes resultados contribuem para o conhecimento dos mecanismos básicos de ação antiviral de bactérias probióticas.
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Humans , Antiviral Agents , Rotavirus/immunology , Probiotics , Integrin beta3ABSTRACT
Interferon (IFN) acts on the surface of the target cell receptors and activate the expression of interferon stimulated genes(interferon stimulated genes,ISGs) through a series of signal transduction.ISGs have antiviral and immunomodulation and other biological functions,indicating ISGs are important molecules for interferon to function and have some potential clinical significance.A large number of research results showed that ISGs may predict the antiviral effect of IFN-α;specific expression of ISGs in patients with autoimmune diseases in vivo may be used as a new biomarker for clinical diagnosis of the diseases;ISGs may act as a new target for cancer treatment and have other potential applications.This review mainly focuses on the induction,the biological functions like antiviral effects and the potential clinical significance of ISGs.
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Objective To verify the antiviral effects of Siji Kangbingdu mixture (SJKBDM) against coxsackievirus A16 (CoxA16).Methods Vero cells and 5-day-old suckling mice, injected with 75/50 and 1×106 TCID50 CoxA16, were used as evaluation models.The preventive influences of SJKBDM against CoxA16 in Vero cells were assessed in the models.The effects of SJKBDM on the mortality, survival time, change rate of body weight, and clinical symptom scores of suckling mice were observed.Results ①The half maximal inhibitory concentration of SJKBDM on Vero cells was 9.59 mg·mL-1.②Toxic effects were not observed from 32.3 g·kg-1 single dose or continuous intraperitoneal injectin of SJKBDM in suckling BALB/c mice.③The SJKBDM had significant inhibitory effect against CoxA16 virus.Doses higher than 1.22 mg·mL-1 could significantly improve the Vero cell survival rate, and the SJKBDM inhibition of 75/50 TCID50 CoxA16 induced pathological changes in Vero cells.④The SJKBDM significantly improved clinical symptoms of mice with CoxA16 viral infection, especially with crude drug doses of higher than 1.62 g·kg-1.The survival rate and other indicators were comparable or slightly higher compared with ribavirin, and the clinical score was higher than that of ribavirin.Conclusion The SJKBDM has significant inhibitory effect on CoxA16 cell proliferation, significantly decreases death rate, and improves clinical symptoms of mice infected with CoxA16 virus.
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Viral infections are the major causes of morbidity and mortality in elderly people and young children throughout the world. The most common pathogens include coxsackie virus (CV) and respiratory syncytial virus (RSV). However, no antiviral agents with low toxicity and drug resistance are currently available in clinic therapy. The present study aimed to examine the antiviral activities of emodin (an ingredient of Rheum palmatum) against CVB5 and RSV infections, in an attempt to discover new antiviral agents for virus infection. The monomer emodin was extracted and isolated from Rheum palmatum. The antiviral activities of emodin on HEp-2 cells were evaluated, including virus replication inhibition, virucidal and anti-absorption effects, by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tet-razolium bromide (MTT) assay and plaque reduction assay (PRA). The kinetics of virus inhibition by emodin in a period of 14 h was further determined by plaque assay and quantitative real time PCR (qPCR). Cytokine (IFN-γ, TNF-α) mRNA expressions after emodin treatment (7.5, 15, 30 μmol/L) were also assessed by qPCR post-infection. The results showed that emodin had potent inhibitory activities against CVB5 and RSV, with the 50% effective concentration (EC50) ranging from 13.06 to 14.27 μmol/L and selectivity index (SI) being 5.38-6.41 μmol/L. However, emodin couldn't directly inactivate the viruses or block their absorption to cells. It acted as a biological synthesis inhibitor against CVB4 and RSV in a concentration- and time-dependent manner, especially during the first 0-4 h post-infection. Moreover, emodin could decrease the mRNA expression of IFN-α but enhance TNF-γ expression significantly compared to the viral controls in vitro. Our results provide a molecular basis for development of emodin as a novel and safe antiviral agent for human enterovirus and respiratory virus infection in the clinical therapy.
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Humans , Antiviral Agents , Pharmacology , Cell Line , Cell Line, Tumor , Emodin , Pharmacology , Enterovirus B, Human , Physiology , In Vitro Techniques , Respiratory Syncytial Viruses , Physiology , Rheum , Chemistry , Virus ReplicationABSTRACT
Objective To evaluate the inhibitory effect of polysaccharides from Selaginella tamariscina on Enterovirus 71 (EV71) replication in vitro. Methods For detecting the cytotoxicity, series of doses of polysaccharides from Selaginella tamariscina were added in RD cells, cell survival rates were evaluated by observing the cytopathic effect (CPE) and using cell counting Kit-8 (CCK8) assay, then the half toxic concentration(CC50) of the drugs were calculated. For studying the antiviral activity, the cellular model was established by infecting RD cells with EV71. Several groups were set in the experiments: normal control group, virus-infected group, positive drug treated EV71 -infected group(ribavirin 3. 2 mg/L) and series of doses of polysaccharides treated EV71 -infected groups. The CPE inhibitions were determined by using CCK8 assay and the half inhibitory concentrations of drugs(IC50) were calculated. The inhibitiory effect of polysaccharides on EV71 RNA were determined by using real-time RT-PCR methods for detecting the virus RNA levels in cell cultures. Results The CC50 of 30% and 50% alcohol precipitated polysaccharides from Selaginella tamariscina on RD cells were 396 and 142 mg/L, respectively; the IC50 calculated according to the CPE inhibitory rates were respectively 40. 8 and 26. 2 mg/L. Additionally, these two polysaccharides significantly reduced viral RNA copies in EV71-infected RD cells. Conclusion Selaginella tamariscina together with its 30% and 50% alcohol precipitated polysaccharides can be developed as potential new anti - E V 71 drugs.
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Objective To study the antiviral effects of SJ-GAG on herpes simplex virus Ⅰ(HSV-Ⅰ) in vitro as well as its protective effect on infected mice.Methods The Vero cells were exposed to HSV-Ⅰ SM44 and different concentrations of SJ-GAG,respectively.Cytopathic effect(CPE) was observed and qunatitative PCR was used to evaluate the antiviral effect of SJ-GAG.In vivo experiment,the mice were infected with HSV1 intracranial vaccination and followed SJ-GAG intragastric administration 4h later to test the protection of SJ-GAG on HSV1 infected mice.Results When the concentration of SJ-GAG was above 1.6mg?mL-1,it showed cytotoxicity.When the concentration was among 0.25~0.2mg?mL-1,it expressed marked antiviral effect without cytotoxicity.SJ-GAG could prolong the survival duration of infected mice and decrease the mortality rate significantly.The protection of SJ-GAG showed a dose-effect relationship.Conclusion SJ-GAG has antiviral effect and shows some protective effect on HSV-1 infected mice.
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Objective: This study aimed to investigate the induction of MxA protein in PBMC treated with various doses of adenovirus type 3(Ad3) and to test the antiviral effect of MxA protein against Ad3 in vitro.Methods:The content of MxA protein in cytoplasm of the peripheral blood mononuclear cells( PBMC) , which were treated with various dose of Ad3 was detected by flow cytometry. The antiviral effect of MxA protein against Ad3 in Hela cells was studied by the microdose cytopathogenic effect inhibition assay. Results: MxA protein that in all the cell groups that were treated with various dose of Ad3 was higher than that of control. 10 ng/ml MxA protein can resist 20TCID50 Aad3. Conclusion: It was suggest that MxA protein that can be induced by Ad3 in PBMC and recombinant MxA can resist Ad3.
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Objective To investigate antiviral and immunoregulation effects of indole-2,3-dine(ISA).Methods The BHK-21 cell model infected with Sendai virus was established and the antiviral effect of ISA was observed by cytopathic effect(CPE) method;its effect on immunological function was observed by hemagglutination inhibition test using Sendai virus infected mice model.Results ISA showed cytotoxicity when the concentration was above(0.313)mg?mL~(-1),while ISA showed a dose-dependent antiviral effect without cytotoxicity when the concentration was among 0.156~0.039mg?mL~(-1).ISA at higher dose(2%) could accelerate the production of hemagglutination inhibition antibody in hemagglutination test(P