Licorice is a leguminous plant of glycyrrhiza. It is a traditional Chinese herbal medicine. Triterpenoid is one of the mainly active components of licorice. In recent years, the broad-spectrum antiviral activity of many triterpenoids in licorice was confirmed, and these findings have become a hot spot of antiviral immunity. The triterpenoids of licorice has the potential to become a novel broad-spectrum antiviral medicine and will be widely used in the clinical treatment. This review provided a summary of the recent anti-virus research progress on several triterpenoids in licorice, such as glycyrrhizic acid, glycyrrhizin, glycyrrhetinic acid and its derivatives. The antiviral roles of triterpenoids in licorice against herpes virus, HIV, hepatitis virus, SARS coronavirus and influenza virus were briefly summarized.

Licorice is a leguminous plant of glycyrrhiza. It is a traditional Chinese herbal medicine. Triterpenoid is one of the mainly active components of licorice. In recent years, the broad-spectrum antiviral activity of many triterpenoids in licorice was confirmed, and these findings have become a hot spot of antiviral immunity. The triterpenoids of licorice has the potential to become a novel broad-spectrum antiviral medicine and will be widely used in the clinical treatment. This review provided a summary of the recent anti-virus research progress on several triterpenoids in licorice, such as glycyrrhizic acid, glycyrrhizin, glycyrrhetinic acid and its derivatives. The antiviral roles of triterpenoids in licorice against herpes virus, HIV, hepatitis virus, SARS coronavirus and influenza virus were briefly summarized.

[n/a]

[n/a]

BACKGROUND:Severe acute respiratory syndrome (SARS) is an acute respiratory disease caused by a novel coronavirus, which first appeared in Foshan City, China on 22 December 2002. Chinese herbs were used in its treatment.

OBJECTIVES:To evaluate the possible effectiveness and safety of Chinese herbs combined with Western medicines versus Western medicines alone for SARS patients.

SEARCH METHODS:We searched CENTRAL 2012, Issue 3, MEDLINE (1966 to February Week 4, 2012), EMBASE (1990 to March 2012) and the Chinese Biomedical Literature (Issue 3, 2012).

SELECTION CRITERIA:Randomised controlled trials (RCTs) and quasi-RCTs of Chinese herbs combined with Western medicines versus Western medicines alone for patients diagnosed with SARS.

DATA COLLECTION AND ANALYSIS:Two review authors (XL, MZ) independently extracted trial data. We extracted dichotomous and continuous data with 95% confidence intervals (CI). For dichotomous data, we used risk ratio (RR). For continuous data, we calculated mean differences (MD). We calculated overall results based on the random-effects model if heterogeneity existed between studies. If no heterogeneity was detected between the studies, we used the fixed-effect model. We used the Z score and the Chi(2) test with significance being set at P<0.05 to test heterogeneity. No severe adverse events were reported.

MAIN RESULTS:We included 12 RCTs and one quasi-RCT. A total of 640 SARS patients and 12 Chinese herbs were identified. We did not find Chinese herbs combined with Western medicines decreased mortality versus Western medicines alone. Two herbs may improve symptoms. Five herbs may improve lung infiltrate absorption. Four herbs may decrease the dosage of corticosteroids. Three herbs may improve the quality of life of SARS patients. One herb may shorten the length of hospital stay.

AUTHORS' CONCLUSIONS:Chinese herbs combined with Western medicines made no difference in decreasing mortality versus Western medicines alone. It is possible that Chinese herbs combined with Western medicines may improve symptoms, quality of life and absorption of pulmonary infiltration, and decrease the corticosteroid dosage for SARS patients. The evidence is weak because of the poor quality of the included trials. Long-term follow-up of these included trials is needed.

BACKGROUND:Severe acute respiratory syndrome (SARS) is an acute respiratory disease caused by a novel coronavirus, which first appeared in Foshan City, China on 22 December 2002. Chinese herbs were used in its treatment.

OBJECTIVES:To evaluate the possible effectiveness and safety of Chinese herbs combined with Western medicines versus Western medicines alone for SARS patients.

SEARCH METHODS:We searched CENTRAL 2012, Issue 3, MEDLINE (1966 to February Week 4, 2012), EMBASE (1990 to March 2012) and the Chinese Biomedical Literature (Issue 3, 2012).

SELECTION CRITERIA:Randomised controlled trials (RCTs) and quasi-RCTs of Chinese herbs combined with Western medicines versus Western medicines alone for patients diagnosed with SARS.

DATA COLLECTION AND ANALYSIS:Two review authors (XL, MZ) independently extracted trial data. We extracted dichotomous and continuous data with 95% confidence intervals (CI). For dichotomous data, we used risk ratio (RR). For continuous data, we calculated mean differences (MD). We calculated overall results based on the random-effects model if heterogeneity existed between studies. If no heterogeneity was detected between the studies, we used the fixed-effect model. We used the Z score and the Chi(2) test with significance being set at P<0.05 to test heterogeneity. No severe adverse events were reported.

MAIN RESULTS:We included 12 RCTs and one quasi-RCT. A total of 640 SARS patients and 12 Chinese herbs were identified. We did not find Chinese herbs combined with Western medicines decreased mortality versus Western medicines alone. Two herbs may improve symptoms. Five herbs may improve lung infiltrate absorption. Four herbs may decrease the dosage of corticosteroids. Three herbs may improve the quality of life of SARS patients. One herb may shorten the length of hospital stay.

AUTHORS' CONCLUSIONS:Chinese herbs combined with Western medicines made no difference in decreasing mortality versus Western medicines alone. It is possible that Chinese herbs combined with Western medicines may improve symptoms, quality of life and absorption of pulmonary infiltration, and decrease the corticosteroid dosage for SARS patients. The evidence is weak because of the poor quality of the included trials. Long-term follow-up of these included trials is needed.

Pneumonia associated with the 2019 novel coronavirus (2019-nCoV) is continuously and rapidly circulating at present. No effective antiviral treatment has been verified thus far. We report here the clinical characteristics and therapeutic procedure for four patients with mild or severe 2019-nCoV pneumonia admitted to Shanghai Public Health Clinical Center. All the patients were given antiviral treatment including lopinavir/ritonavir (Kaletra), arbidol, and Shufeng Jiedu Capsule (SFJDC, a traditional Chinese medicine) and other necessary support care. After treatment, three patients gained significant improvement in pneumonia associated symptoms, two of whom were confirmed 2019-nCoV negative and discharged, and one of whom was virus negative at the first test. The remaining patient with severe pneumonia had shown signs of improvement by the cutoff date for data collection. Results obtained in the current study may provide clues for treatment of 2019-nCoV pneumonia. The efficacy of antiviral treatment including lopinavir/ritonavir, arbidol, and SFJDC warrants further verification in future study.

Pneumonia associated with the 2019 novel coronavirus (2019-nCoV) is continuously and rapidly circulating at present. No effective antiviral treatment has been verified thus far. We report here the clinical characteristics and therapeutic procedure for four patients with mild or severe 2019-nCoV pneumonia admitted to Shanghai Public Health Clinical Center. All the patients were given antiviral treatment including lopinavir/ritonavir (Kaletra), arbidol, and Shufeng Jiedu Capsule (SFJDC, a traditional Chinese medicine) and other necessary support care. After treatment, three patients gained significant improvement in pneumonia associated symptoms, two of whom were confirmed 2019-nCoV negative and discharged, and one of whom was virus negative at the first test. The remaining patient with severe pneumonia had shown signs of improvement by the cutoff date for data collection. Results obtained in the current study may provide clues for treatment of 2019-nCoV pneumonia. The efficacy of antiviral treatment including lopinavir/ritonavir, arbidol, and SFJDC warrants further verification in future study.

OBJECTIVE:To observe the clinic symptom improving time in uncertain SARS patients and the therapeutic effect of integrative Chinese and western medicine (ICWM) in treating SARS.

METHODS:The clinic symptoms, chest film and tongue figure of 40 uncertain SARS patients treated with ICWM were observed and T-lymphocyte subsets, serum coronavirus nucleic acid and antibody in 20 patients were tested dynamically.

RESULTS:All the symptoms, such as fever, sweating, fatigue, cough without phlegm, etc. were obviously improved after treatment. Lung shadow in chest film began to be absorbed 4.54 +/- 2.85 days, and obviously absorbed 7.74 +/- 4.68 days after treatment. CD3, CD4 and CD8 in 20 patients, which were lower than the normal range when hospitalization, began to increase 3 days later and gradually recovered to the normal in 6-10 days. Serum coronavirus nucleic acid was positive in 3 patients, coronavirus antibody positive in two and both were positive in one.

CONCLUSION:ICWM can improve the symptoms and regulate the immune function in uncertain SARS patients.

OBJECTIVE:To observe the clinic symptom improving time in uncertain SARS patients and the therapeutic effect of integrative Chinese and western medicine (ICWM) in treating SARS.

METHODS:The clinic symptoms, chest film and tongue figure of 40 uncertain SARS patients treated with ICWM were observed and T-lymphocyte subsets, serum coronavirus nucleic acid and antibody in 20 patients were tested dynamically.

RESULTS:All the symptoms, such as fever, sweating, fatigue, cough without phlegm, etc. were obviously improved after treatment. Lung shadow in chest film began to be absorbed 4.54 +/- 2.85 days, and obviously absorbed 7.74 +/- 4.68 days after treatment. CD3, CD4 and CD8 in 20 patients, which were lower than the normal range when hospitalization, began to increase 3 days later and gradually recovered to the normal in 6-10 days. Serum coronavirus nucleic acid was positive in 3 patients, coronavirus antibody positive in two and both were positive in one.

CONCLUSION:ICWM can improve the symptoms and regulate the immune function in uncertain SARS patients.

Severe acute respiratory syndrome (SARS) is an emerging infectious disease caused by a novel coronavirus (SARS-CoV). SARS-CoV spike (S) protein, a type I membrane-bound protein, is essential for the viral attachment to the host cell receptor angiotensin-converting enzyme 2 (ACE2). By screening 312 controlled Chinese medicinal herbs supervised by Committee on Chinese Medicine and Pharmacy at Taiwan, we identified that three widely used Chinese medicinal herbs of the family Polygonaceae inhibited the interaction of SARS-CoV S protein and ACE2. The IC(50) values for Radix et Rhizoma Rhei (the root tubers of Rheum officinale Baill.), Radix Polygoni multiflori (the root tubers of Polygonum multiflorum Thunb.), and Caulis Polygoni multiflori (the vines of P. multiflorum Thunb.) ranged from 1 to 10. Emodin, an anthraquinone compound derived from genus Rheum and Polygonum, significantly blocked the S protein and ACE2 interaction in a dose-dependent manner. It also inhibited the infectivity of S protein-pseudotyped retrovirus to Vero E6 cells. These findings suggested that emodin may be considered as a potential lead therapeutic agent in the treatment of SARS.

Severe acute respiratory syndrome (SARS) is an infectious disease with a strong potential for transmission upon close personal contact and is caused by the SARS-coronavirus (CoV). However, there are no natural or synthetic compounds currently available that can inhibit SARS-CoV. We examined the inhibitory effects of 64 purified natural compounds against the activity of SARS helicase, nsP13, and the hepatitis C virus (HCV) helicase, NS3h, by conducting fluorescence resonance energy transfer (FRET)-based double-strand (ds) DNA unwinding assay or by using a colorimetry-based ATP hydrolysis assay. While none of the compounds, examined in our study inhibited the DNA unwinding activity or ATPase activity of human HCV helicase protein, we found that myricetin and scutellarein potently inhibit the SARS-CoV helicase protein in vitro by affecting the ATPase activity, but not the unwinding activity, nsP13. In addition, we observed that myricetin and scutellarein did not exhibit cytotoxicity against normal breast epithelial MCF10A cells. Our study demonstrates for the first time that selected naturally-occurring flavonoids, including myricetin and scultellarein might serve as SARS-CoV chemical inhibitors.

Severe acute respiratory syndrome (SARS) is an infectious disease with a strong potential for transmission upon close personal contact and is caused by the SARS-coronavirus (CoV). However, there are no natural or synthetic compounds currently available that can inhibit SARS-CoV. We examined the inhibitory effects of 64 purified natural compounds against the activity of SARS helicase, nsP13, and the hepatitis C virus (HCV) helicase, NS3h, by conducting fluorescence resonance energy transfer (FRET)-based double-strand (ds) DNA unwinding assay or by using a colorimetry-based ATP hydrolysis assay. While none of the compounds, examined in our study inhibited the DNA unwinding activity or ATPase activity of human HCV helicase protein, we found that myricetin and scutellarein potently inhibit the SARS-CoV helicase protein in vitro by affecting the ATPase activity, but not the unwinding activity, nsP13. In addition, we observed that myricetin and scutellarein did not exhibit cytotoxicity against normal breast epithelial MCF10A cells. Our study demonstrates for the first time that selected naturally-occurring flavonoids, including myricetin and scultellarein might serve as SARS-CoV chemical inhibitors.

More than 200 Chinese medicinal herb extracts were screened for antiviral activities against Severe Acute Respiratory Syndrome-associated coronavirus (SARS-CoV) using 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium inner salt (MTS) assay for virus-induced cytopathic effect (CPE). Four of these extracts showed moderate to potent antiviral activities against SARS-CoV with 50% effective concentration (EC50) ranging from 2.4 +/- 0.2 to 88.2 +/- 7.7 microg/ml. Out of the four, Lycoris radiata was most potent. To identify the active component, L. radiata extract was subjected to further fractionation, purification, and CPE/MTS assays. This process led to the identification of a single substance lycorine as an anti-SARS-CoV component with an EC50 value of 15.7 +/- 1.2 nM. This compound has a CC50 value of 14980.0 +/- 912.0 nM in cytotoxicity assay and a selective index (SI) greater than 900. The results suggested that four herbal extracts and the compound lycorine are candidates for the development of new anti-SARS-CoV drugs in the treatment of SARS.

More than 200 Chinese medicinal herb extracts were screened for antiviral activities against Severe Acute Respiratory Syndrome-associated coronavirus (SARS-CoV) using 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium inner salt (MTS) assay for virus-induced cytopathic effect (CPE). Four of these extracts showed moderate to potent antiviral activities against SARS-CoV with 50% effective concentration (EC50) ranging from 2.4 +/- 0.2 to 88.2 +/- 7.7 microg/ml. Out of the four, Lycoris radiata was most potent. To identify the active component, L. radiata extract was subjected to further fractionation, purification, and CPE/MTS assays. This process led to the identification of a single substance lycorine as an anti-SARS-CoV component with an EC50 value of 15.7 +/- 1.2 nM. This compound has a CC50 value of 14980.0 +/- 912.0 nM in cytotoxicity assay and a selective index (SI) greater than 900. The results suggested that four herbal extracts and the compound lycorine are candidates for the development of new anti-SARS-CoV drugs in the treatment of SARS.

It has been reported that lactoferrin (LF) participates in the host immune response against Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) invasion by enhancing NK cell activity and stimulating neutrophil aggregation and adhesion. We further investigated the role of LF in the entry of SARS pseudovirus into HEK293E/ACE2-Myc cells. Our results reveal that LF inhibits SARS pseudovirus infection in a dose-dependent manner. Further analysis suggested that LF was able to block the binding of spike protein to host cells at 4°C, indicating that LF exerted its inhibitory function at the viral attachment stage. However, LF did not disrupt the interaction of spike protein with angiotensin-converting enzyme 2 (ACE2), the functional receptor of SARS-CoV. Previous studies have shown that LF colocalizes with the widely distributed cell-surface heparan sulfate proteoglycans (HSPGs). Our experiments have also confirmed this conclusion. Treatment of the cells with heparinase or exogenous heparin prevented binding of spike protein to host cells and inhibited SARS pseudovirus infection, demonstrating that HSPGs provide the binding sites for SARS-CoV invasion at the early attachment phase. Taken together, our results suggest that, in addition to ACE2, HSPGs are essential cell-surface molecules involved in SARS-CoV cell entry. LF may play a protective role in host defense against SARS-CoV infection through binding to HSPGs and blocking the preliminary interaction between SARS-CoV and host cells. Our findings may provide further understanding of SARS-CoV pathogenesis and aid in treatment of this deadly disease.

SARS-CoV is the causative agent of severe acute respiratory syndrome (SARS). The virally encoded 3C-like protease (3CL(Pro)) has been presumed critical for the viral replication of SARS-CoV in infected host cells. In this study, we screened a natural product library consisting of 720 compounds for inhibitory activity against 3CL(Pro). Two compounds in the library were found to be inhibitive: tannic acid (IC(50) = 3 microM) and 3-isotheaflavin-3-gallate (TF2B) (IC(50) = 7 microM). These two compounds belong to a group of natural polyphenols found in tea. We further investigated the 3CL(Pro)-inhibitory activity of extracts from several different types of teas, including green tea, oolong tea, Puer tea and black tea. Our results indicated that extracts from Puer and black tea were more potent than that from green or oolong teas in their inhibitory activities against 3CL(Pro). Several other known compositions in teas were also evaluated for their activities in inhibiting 3CL(Pro). We found that caffeine, (-)-epigallocatechin gallte (EGCg), epicatechin (EC), theophylline (TP), catechin (C), epicatechin gallate (ECg) and epigallocatechin (EGC) did not inhibit 3CL(Pro) activity. Only theaflavin-3,3'-digallate (TF3) was found to be a 3CL(Pro) inhibitor. This study has resulted in the identification of new compounds that are effective 3CL(Pro) inhibitors.

SARS-CoV is the causative agent of severe acute respiratory syndrome (SARS). The virally encoded 3C-like protease (3CL(Pro)) has been presumed critical for the viral replication of SARS-CoV in infected host cells. In this study, we screened a natural product library consisting of 720 compounds for inhibitory activity against 3CL(Pro). Two compounds in the library were found to be inhibitive: tannic acid (IC(50) = 3 microM) and 3-isotheaflavin-3-gallate (TF2B) (IC(50) = 7 microM). These two compounds belong to a group of natural polyphenols found in tea. We further investigated the 3CL(Pro)-inhibitory activity of extracts from several different types of teas, including green tea, oolong tea, Puer tea and black tea. Our results indicated that extracts from Puer and black tea were more potent than that from green or oolong teas in their inhibitory activities against 3CL(Pro). Several other known compositions in teas were also evaluated for their activities in inhibiting 3CL(Pro). We found that caffeine, (-)-epigallocatechin gallte (EGCg), epicatechin (EC), theophylline (TP), catechin (C), epicatechin gallate (ECg) and epigallocatechin (EGC) did not inhibit 3CL(Pro) activity. Only theaflavin-3,3'-digallate (TF3) was found to be a 3CL(Pro) inhibitor. This study has resulted in the identification of new compounds that are effective 3CL(Pro) inhibitors.

and other related species ofare the major sources of the bis-benzylisoquinoline alkaloids tetrandrine (TET), fangchinoline (FAN), and cepharanthine (CEP). Although the pharmacological properties of these compounds include anticancer and anti-inflammatory activities, the antiviral effects of these compounds against human coronavirus (HCoV) remain unclear. Hence, the aims of the current study were to assess the antiviral activities of TET, FAN, and CEP and to elucidate the underlying mechanisms in HCoV-OC43-infected MRC-5 human lung cells. These compounds significantly inhibited virus-induced cell death at the early stage of virus infection. TET, FAN, and CEP treatment dramatically suppressed the replication of HCoV-OC43 as well as inhibited viral S and N protein expression. The virus-induced host response was reduced by compound treatment as compared with the vehicle control. Taken together, these findings demonstrate that TET, FAN, and CEP are potential natural antiviral agents for the prevention and treatment of HCoV-OC43 infection.

and other related species ofare the major sources of the bis-benzylisoquinoline alkaloids tetrandrine (TET), fangchinoline (FAN), and cepharanthine (CEP). Although the pharmacological properties of these compounds include anticancer and anti-inflammatory activities, the antiviral effects of these compounds against human coronavirus (HCoV) remain unclear. Hence, the aims of the current study were to assess the antiviral activities of TET, FAN, and CEP and to elucidate the underlying mechanisms in HCoV-OC43-infected MRC-5 human lung cells. These compounds significantly inhibited virus-induced cell death at the early stage of virus infection. TET, FAN, and CEP treatment dramatically suppressed the replication of HCoV-OC43 as well as inhibited viral S and N protein expression. The virus-induced host response was reduced by compound treatment as compared with the vehicle control. Taken together, these findings demonstrate that TET, FAN, and CEP are potential natural antiviral agents for the prevention and treatment of HCoV-OC43 infection.