To explore the polysaccharides from selected seaweeds of Atlantic Canada and to evaluate their potential anti-influenza virus activities, polysaccharides were isolated from several Atlantic Canadian seaweeds, includin...To explore the polysaccharides from selected seaweeds of Atlantic Canada and to evaluate their potential anti-influenza virus activities, polysaccharides were isolated from several Atlantic Canadian seaweeds, including three red algae (Polysiphonia lanosa, Furcellaria lumbricalis, and Palmaria palmata), two brown algae (Ascophyllum nodosum and Fucus vesiculosus), and one green alga (Ulva lactuca) by sequential extraction with cold water, hot water, and alkali solutions. These polysaccharides were ana-lyzed for monosaccharide composition and other general chemical properties, and they were evaluated for anti-influenza virus activities. Total sugar contents in these polysaccharides ranged from 15.4% (in U. lactuca) to 91.4% (in F. lumbricalis); sulfation level was as high as 17.6% in a polysaccharide from U. lactuca, whereas it could not be detected in an alikali-extract from P. palmaria. For polysaccharides from red seaweeds, the main sugar units were sulfated galactans (agar or carrageenan) for P. lanosa, F. lumbricalis, and xylans for P. palmata. In brown seaweeds, the polysaccharides largely contained sulfated fucans, whereas the polysaccharides in green seaweed were mainly composed of heteroglycuronans. Screening for antiviral activity against influenza A/PR/8/34 (H1N1) virus revealed that brown algal polysaccharides were particularly effective. Seaweeds from Atlantic Canada are a good source of marine polysaccharides with potential antiviral properties.展开更多
OBJECTIVE Sheng Jiang San(SJS),a multi-herb formulation,is used in treating high fever,thirsty and anxiety in ancient China and it is sometimes used to treat seasonal influenza in modern.However,there is no evidenceba...OBJECTIVE Sheng Jiang San(SJS),a multi-herb formulation,is used in treating high fever,thirsty and anxiety in ancient China and it is sometimes used to treat seasonal influenza in modern.However,there is no evidencebased investigation and mechanism research to support SJS′s anti-influenza efficacy.This study aims to investigate the anti-influenza effect of SJS and its possible mechanisms.METHODS In this study,we examined the inhibitory effect of SJS against different influenza viruses on Madin-Darby canine kidney cells.Influenza virus infected BALB/c mice were employed as in vivo model to evaluate the efficacy.Mice challenged with A/PR/8/34(H1N1)were orally administrated SJS 1 g·kg^-1 daily for seven days and monitored for 14 d.The survival rate,body mass changes,lung index,lung viral load,histopathologic changes and immune-regulation of the mice were measured.The underlying anti-influenza virus mechanisms were studied by a series of biological assays in vitro to determine if hemagglutinin,ribonucleoprotein complex or nerauminidase were targets of SJS.RESULTS SJS exerted a broad spectrum of inhibitory effects on multiple influenza strains in a dose-dependent manner.And IC50 of SJS against A/WSN/33(H1N1)was lower than 35 mg·L^-1.SJS also protected 50%of mice from influenza virus PR8 infection.The lung index and the lung viral load of SJS treated mice were signifi⁃cantly decrease compared with untreated mice.SJS 2 g·L^-1 inhibited 80%of neuraminidase enzymatic activity.SJS also up-regulated TNF-αand IFN-αand down-regulated IL-2 of influenza virus induced mice.CONCLUSION SJS is a useful formulation for treating influenza virus infection.展开更多
A series of ethyl 6-bromo-5-hydroxyindole-3-carboxylate derivatives were synthesized and their in vitro anti-influenza virus activity was evaluated. All the compounds were characterized by 1H NMR and MS.
Anti-influenza Chinese herbal medicines(anti-flu CHMs) have advantages in preventing and treating influenza virus infection. Despite various data on antiviral activities of some anti-flu CHMs have been reported, most ...Anti-influenza Chinese herbal medicines(anti-flu CHMs) have advantages in preventing and treating influenza virus infection. Despite various data on antiviral activities of some anti-flu CHMs have been reported, most of them could not be compared using the standard evaluation methods for antiviral activity. This situation poses an obstacle to a wide application of anti-flu CHMs. Thus, it was necessary to develop an evaluation method to estimate antiviral activities of anti-flu CHMs. In the present study, we searched for anti-flu CHMs, based on clinic usage, to select study objects from commonly-used patented anti-flu Chinese medicines. Then, a neuraminidase-based bioassay, optimized and verified by HPLC method by our research group, was adopted to detect antiviral activities of selected 26 anti-flu CHMs. Finally, eight of these herbs, including Coptidis Rhizoma, Isatidis Folium, Lonicerae Flos, Scutellaria Radix, Cyrtomium Rhizome, Houttuynia Cordata, Gardeniae Fructus, and Chrysanthemi Indici Flos, were shown to have strong antiviral activities with half maximal inhibitory concentration(IC_(50)) values being 2.02 to 6.78 mg·m L^(–1)(expressed as raw materials). In contrast, the IC_(50) value of positive control peramivir was 0.38 mg·m L^(–1). Considering the extract yields of CHMs, the active component in these herbs may have a stronger antiviral activity than peramivir, suggesting that these herbs could be further researched for active compounds. Moreover, the proposed neuraminidase-based bioassay was high-throughput and simple and could be used for evaluation and screening of anti-flu CHMs as well as for their quality control.展开更多
PA_C subunit from avian influenza（H5N1） viral RNA polymerase was used in this work as a target in the screening for anti-influenza agents from licorice-derived compounds.As a result,18β-glycyrrhetinic acid was sugg...PA_C subunit from avian influenza（H5N1） viral RNA polymerase was used in this work as a target in the screening for anti-influenza agents from licorice-derived compounds.As a result,18β-glycyrrhetinic acid was suggested to be PA_C ligand by flexible docking,and was then confirmed by relaxation-edited NMR.The result of ApG primer extension assay indicated that this PA_C ligand can inhibit the polymerase activity,and thus may potentially be valuable as anti-influenza lead compound.This work validated the possibility of screening polymerase inhibitors by using PA_C as a target,and provided a starting point for the further discovery of new anti-influenza drugs.展开更多
基金supported in part by the Program for Changjiang Scholars and Innovative Research Team in University (IRT0944)Special Fund for Marine Scientific Research in the Public Interest (201005024)the Natural Science Foundation of China (31070724), and China Scholarship Council, the Ministry of Education and National Research Council Canada-Institute for Marine Biosciences and Institute for Nutrisciences and Health
文摘To explore the polysaccharides from selected seaweeds of Atlantic Canada and to evaluate their potential anti-influenza virus activities, polysaccharides were isolated from several Atlantic Canadian seaweeds, including three red algae (Polysiphonia lanosa, Furcellaria lumbricalis, and Palmaria palmata), two brown algae (Ascophyllum nodosum and Fucus vesiculosus), and one green alga (Ulva lactuca) by sequential extraction with cold water, hot water, and alkali solutions. These polysaccharides were ana-lyzed for monosaccharide composition and other general chemical properties, and they were evaluated for anti-influenza virus activities. Total sugar contents in these polysaccharides ranged from 15.4% (in U. lactuca) to 91.4% (in F. lumbricalis); sulfation level was as high as 17.6% in a polysaccharide from U. lactuca, whereas it could not be detected in an alikali-extract from P. palmaria. For polysaccharides from red seaweeds, the main sugar units were sulfated galactans (agar or carrageenan) for P. lanosa, F. lumbricalis, and xylans for P. palmata. In brown seaweeds, the polysaccharides largely contained sulfated fucans, whereas the polysaccharides in green seaweed were mainly composed of heteroglycuronans. Screening for antiviral activity against influenza A/PR/8/34 (H1N1) virus revealed that brown algal polysaccharides were particularly effective. Seaweeds from Atlantic Canada are a good source of marine polysaccharides with potential antiviral properties.
文摘OBJECTIVE Sheng Jiang San(SJS),a multi-herb formulation,is used in treating high fever,thirsty and anxiety in ancient China and it is sometimes used to treat seasonal influenza in modern.However,there is no evidencebased investigation and mechanism research to support SJS′s anti-influenza efficacy.This study aims to investigate the anti-influenza effect of SJS and its possible mechanisms.METHODS In this study,we examined the inhibitory effect of SJS against different influenza viruses on Madin-Darby canine kidney cells.Influenza virus infected BALB/c mice were employed as in vivo model to evaluate the efficacy.Mice challenged with A/PR/8/34(H1N1)were orally administrated SJS 1 g·kg^-1 daily for seven days and monitored for 14 d.The survival rate,body mass changes,lung index,lung viral load,histopathologic changes and immune-regulation of the mice were measured.The underlying anti-influenza virus mechanisms were studied by a series of biological assays in vitro to determine if hemagglutinin,ribonucleoprotein complex or nerauminidase were targets of SJS.RESULTS SJS exerted a broad spectrum of inhibitory effects on multiple influenza strains in a dose-dependent manner.And IC50 of SJS against A/WSN/33(H1N1)was lower than 35 mg·L^-1.SJS also protected 50%of mice from influenza virus PR8 infection.The lung index and the lung viral load of SJS treated mice were signifi⁃cantly decrease compared with untreated mice.SJS 2 g·L^-1 inhibited 80%of neuraminidase enzymatic activity.SJS also up-regulated TNF-αand IFN-αand down-regulated IL-2 of influenza virus induced mice.CONCLUSION SJS is a useful formulation for treating influenza virus infection.
文摘A series of ethyl 6-bromo-5-hydroxyindole-3-carboxylate derivatives were synthesized and their in vitro anti-influenza virus activity was evaluated. All the compounds were characterized by 1H NMR and MS.
基金supported by the National Natural Science Foundation of China(Nos.81274026,81403126,81330090,81573676)
文摘Anti-influenza Chinese herbal medicines(anti-flu CHMs) have advantages in preventing and treating influenza virus infection. Despite various data on antiviral activities of some anti-flu CHMs have been reported, most of them could not be compared using the standard evaluation methods for antiviral activity. This situation poses an obstacle to a wide application of anti-flu CHMs. Thus, it was necessary to develop an evaluation method to estimate antiviral activities of anti-flu CHMs. In the present study, we searched for anti-flu CHMs, based on clinic usage, to select study objects from commonly-used patented anti-flu Chinese medicines. Then, a neuraminidase-based bioassay, optimized and verified by HPLC method by our research group, was adopted to detect antiviral activities of selected 26 anti-flu CHMs. Finally, eight of these herbs, including Coptidis Rhizoma, Isatidis Folium, Lonicerae Flos, Scutellaria Radix, Cyrtomium Rhizome, Houttuynia Cordata, Gardeniae Fructus, and Chrysanthemi Indici Flos, were shown to have strong antiviral activities with half maximal inhibitory concentration(IC_(50)) values being 2.02 to 6.78 mg·m L^(–1)(expressed as raw materials). In contrast, the IC_(50) value of positive control peramivir was 0.38 mg·m L^(–1). Considering the extract yields of CHMs, the active component in these herbs may have a stronger antiviral activity than peramivir, suggesting that these herbs could be further researched for active compounds. Moreover, the proposed neuraminidase-based bioassay was high-throughput and simple and could be used for evaluation and screening of anti-flu CHMs as well as for their quality control.
基金supported by the National Natural Science Foundation of China(No.81072576) to Y.L.Tangthe National Natural Science Foundation of China(No. 30925011)the Ministry of Science and Technology 863 Project(No.2006AA02A314) to Y.F.Liu
文摘PA_C subunit from avian influenza（H5N1） viral RNA polymerase was used in this work as a target in the screening for anti-influenza agents from licorice-derived compounds.As a result,18β-glycyrrhetinic acid was suggested to be PA_C ligand by flexible docking,and was then confirmed by relaxation-edited NMR.The result of ApG primer extension assay indicated that this PA_C ligand can inhibit the polymerase activity,and thus may potentially be valuable as anti-influenza lead compound.This work validated the possibility of screening polymerase inhibitors by using PA_C as a target,and provided a starting point for the further discovery of new anti-influenza drugs.
