Effects of Lianhuaqingwen Capsules in adults with mild-to-moderate coronavirus disease 2019: an international, multicenter, double-blind, randomized controlled trial.

BACKGROUND: In a randomized trial, Lianhuaqingwen (LHQW) capsule was effective for accelerating symptom recovery among patients with coronavirus disease 2019 (COVID-19). However, the lack of blinding and limited sample sizes decreased the level of clinical evidence. OBJECTIVES: To evaluate the efficacy and safety of LHQW capsule in adults with mild-to-moderate COVID-19. METHODS: We conducted a double-blind randomized controlled trial in adults with mild-to-moderate COVID-19 (17 sites from China, Thailand, Philippine and Vietnam). Patients received standard-of-care alone or plus LHQW capsules (4 capsules, thrice daily) for 14 days. The primary endpoint was the median time to sustained clinical improvement or resolution of nine major symptoms. RESULTS: The full-analysis set consisted of 410 patients in LHQW capsules and 405 in placebo group. LHQW significantly shortened the primary endpoint in the full-analysis set (4.0 vs. 6.7 days, hazards ratio: 1.63, 95% confidence interval: 1.39-1.90). LHQW capsules shortened the median time to sustained clinical improvement or resolution of stuffy or runny nose (2.8 vs. 3.7 days), sore throat (2.0 vs. 2.6 days), cough (3.2 vs. 4.9 days), feeling hot or feverish (1.0 vs. 1.3 days), low energy or tiredness (1.3 vs. 1.9 days), and myalgia (1.5 vs. 2.0 days). The duration to sustained clinical improvement or resolution of shortness of breath, headache, and chills or shivering did not differ significantly between the two groups. Safety was comparable between the two groups. No serious adverse events were reported. INTERPRETATION: LHQW capsules promote recovery of mild-to-moderate COVID-19 via accelerating symptom resolution and were well tolerated. Trial registration ChiCTR2200056727 .

Integrated network pharmacology analysis, molecular docking, LC-MS analysis and bioassays revealed the potential active ingredients and underlying mechanism of Scutellariae radix for COVID-19.

Scutellariae radix ("Huang-Qin" in Chinese) is a well-known traditional herbal medicine and popular dietary supplement in the world, extensively used in prescriptions of TCMs as adjuvant treatments for coronavirus pneumonia 2019 (COVID-19) patients in China. According to the differences in its appearance, Scutellariae radix can be classified into two kinds: ZiQin (1∼3 year-old Scutellariae baicalensis with hard roots) and KuQin (more than 3 year-old S. baicalensis with withered pithy roots). In accordance with the clinical theory of TCM, KuQin is superior to ZiQin in cooling down the heat in the lung. However, the potential active ingredients and underlying mechanisms of Scutellariae radix for the treatment of COVID-19 remain largely unexplored. It is still not clear whether there is a difference in the curative effect of ZiQin and KuQin for the treatment of COVID-19. In this research, network pharmacology, LC-MS based plant metabolomics, and in vitro bioassays were integrated to explore both the potential active components and mechanism of Scutellariae radix for the treatment of COVID-19. As the results, network pharmacology combined with molecular docking analysis indicated that Scutellariae radix primarily regulates the MAPK and NF-κB signaling pathways via active components such as baicalein and scutellarin, and blocks SARS-CoV-2 spike binding to human ACE2 receptors. In vitro bioassays showed that baicalein and scutellarein exhibited more potent anti-inflammatory and anti-infectious effects than baicalin, the component with the highest content in Scutellariae radix. Moreover, baicalein inhibited SARS-CoV-2's entry into Vero E6 cells with an IC50 value of 142.50 µM in a plaque formation assay. Taken together, baicalein was considered to be the most crucial active component of Scutellariae radix for the treatment of COVID-19 by integrative analysis. In addition, our bioassay study revealed that KuQin outperforms ZiQin in the treatment of COVID-19. Meanwhile, plant metabolomics revealed that baicalein was the compound with the most significant increase in KuQin compared to ZiQin, implying the primary reason for the superiority of KuQin over ZiQin in the treatment of COVID-19.

[Thoughts on path of R&D and registration of innovative traditional Chinese medicine with synchronous transformation of "series prescriptions"].

Since the implementation of drug registration in China, the classification of Chinese medicine has greatly met the needs of public health and effectively guided the transformation, inheritance, and innovation of research achievements on traditional Chinese medicine(TCM). In the past 30 years, the development of new Chinese medicine has followed the registration transformation model of " one prescription for single drug". This model refers to the R&D and registration system of modern drugs, and approximates to the " law-abiding" medication method in TCM clinic, while it rarely reflects the sequential therapy of syndrome differentiation and comprehensive treatment with multiple measures. In 2017, Opinions on Deepening the Reform of Review and Approval System and Encouraging the Innovation of Drugs and Medical Devices released by the General Office of the CPC Central Committee and the General Office of the State Council pointed out that it is necessary to " establish and improve the registration and technical evaluation system in line with the characteristics of Chinese medicine, and handle the relationship between the traditional advantages of Chinese medicine and the requirements of modern drug research". Therefore, based on the development law and characteristics of TCM, clinical thinking should be highlighted in the current technical requirements and registration system of research and development of Chinese medicine. Based on the current situation of registration supervision of Chinese medicine and the modern drug research in China, the present study analyzed limitations and deficiency of " one prescription for single drug" in the research and development of Chinese medicine. Additionally, a new type of " series prescriptions" was proposed, which was consistent with clinical thinking and clinical reality. This study is expected to contribute to the independent innovation and high-quality development of the TCM industry.

Total alkaloids from Alstonia scholaris inhibit influenza a virus replication and lung immunopathology by regulating the innate immune response.

BACKGROUND: Alstonia scholaris is a folk medicine used to treat cough, asthma and chronic obstructive pulmonary disease in China. Total alkaloids (TA) from A. scholaris exhibit anti-inflammatory properties in acute respiratory disease, which suggests their possible anti-inflammatory effect on influenza virus infection. PURPOSE: To assess the clinical use of TA by demonstrating their anti-influenza and anti-inflammatory effects and the possible mechanism underlying the effect of TA on influenza A virus (IAV) infection in vitro and to reveal the inhibitory effect of TA on lung immunopathology caused by IAV infection. METHODS: Antiviral and anti-inflammatory activities were assessed in Madin-Darby canine kidney (MDCK) and A549 cells and U937-derived macrophages infected with influenza A/PR/8/34 (H1N1) virus. Proinflammatory cytokine levels were measured by real-time quantitative PCR and Bio-Plex assays. The activation of innate immune signaling induced by H1N1 virus in the absence or presence of TA was detected in A549 cells by Western blot. Furthermore, mice were infected intranasally with H1N1 virus and treated with TA (50, 25 and 12.5 mg/kg/d) or oseltamivir (60 mg/kg/d) for 5 days in vivo. The survival rates and body weight were recorded, and the viral titer, proinflammatory cytokine levels, innate immune cell populations and histopathological changes in the lungs were analyzed. RESULTS: TA significantly inhibited viral replication in A549 cells and U937-derived macrophages and markedly reduced cytokine and chemokine production at the mRNA and protein levels. Furthermore, TA blocked the activation of pattern recognition receptor (PRR)- and IFN-activated signal transduction in A549 cells. Critically, TA also increased the survival rate, reduced the viral titer, suppressed proinflammatory cytokine production and innate immune cell infiltration and improved lung histopathology in a lethal PR8 mouse model. CONCLUSION: TA exhibits anti-viral and anti-inflammatory effects against IAV infection by interfering with PRR- and IFN-activated signal transduction.

Indole alkaloids from leaves of Alstonia scholaris (L.) R. Br. protect against emphysema in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Alstonia scholaris (L.) R. Br. (Apocynaceae) is a medicinal plant in China traditionally used to treat pulmonary diseases, including bronchitis, whooping cough, asthma and chronic obstructive pulmonary disease. AIM OF THE STUDY: To provide experimental data supporting clinical adaptation of total indole alkaloids ( TA) from A. scholaris leaves for treating emphysema. MATERIALS AND METHODS: An emphysema model was induced by a single intratracheal instillation of porcine pancreatic elastase followed by administration of TA and four main alkaloid components (scholaricine, 19-epischolaricine, vallesamine, and picrinine) for 30 consecutive days. Cytokine levels, histopathological parameters and protein expression in lung tissues were examined. RESULTS: Administering the TA, picrinine, scholaricine, 19-epischolaricine and vallesamine for 30 days effectively inhibited inflammatory cell accumulation and invasion in the lung tissue and relieved pulmonary tissue injury. Oxygen saturation was enhanced, and interleukin (IL)-1ß, monocyte-chemo attractive peptide 1, IL-11, matrix metalloproteinase-12, transforming growth factor-ß and vascular endothelial growth factor levels were significantly reduced, likely by suppressing overactivation of alveolar macrophages and pulmonary fibrosis. The elastin content was markedly elevated, and fibronectin was reduced. Bcl-2 expression was significantly increased, and nuclear factor-κB and ß-catenin levels were decreased. CONCLUSIONS: TA can be potentially used as an effective novel drug for pulmonary emphysema and exerts its effects through not only inhibiting inflammation of the airway wall and airflow resistance but also promoting lung elastic recoil and protease/anti-protease balance.

Efficacy of indoor air purification in the treatment of Artemisia pollen-allergic rhinitis: A randomised, double-blind, clinical controlled trial.

OBJECTIVES: To evaluate the clinical efficacy of a high-efficiency air purifier in patients with allergic rhinitis. DESIGN: We conducted a randomised, double-blind, clinical controlled trial with active and inactive versions of an air purifier. Our study included patients with allergic rhinitis who were sensitive to Artemisia pollen and treatment of the indoor environment using air filtration at night. We evaluated the clinical efficacy of indoor air filtration during the Artemisia pollen scattering season in Yulin City in Shanxi Province, China. SETTING: The First Hospital of Yulin (Yulin City, Shanxi Province, China). PARTICIPANTS: A total of 90 patients with allergic rhinitis who were sensitive to allergens of Artemisia pollen were randomly assigned to one of two groups in equal numbers. MAIN OUTCOME MEASURES: The primary outcome measure was the difference in visual analogue scale scores from baseline. Secondary outcomes were changes from baseline in nasal symptoms, allergy symptom scores, responses to the Rhinoconjunctivitis Quality of Life Questionnaire, Epworth Sleepiness Scale scores and tolerability scores for the air purifier. RESULTS: Based on the allergy symptom score, we found significant differences in rhinitis symptoms between the groups who used the active versus the inactive air purifier. CONCLUSIONS: The results of our investigation demonstrated the health benefits of particle filtration.

Efficacy and safety of Chou-Ling-Dan granules in the treatment of seasonal influenza via combining Western and traditional Chinese medicine: protocol for a multicentre, randomised controlled clinical trial.

INTRODUCTION: Chou-Ling-Dan (CLD) (Laggerapterodonta) granules are an ethnic herbal medicine from Yunnan province of China. CLD granules have been used for the treatment of inflammatory conditions and feverish diseases in China, including seasonal influenza, but few evidence-based medicine (EBM) clinical studies have been conducted to assess its efficacy and safety in the treatment of influenza. Here, we performed an EBM clinical trial combining Western Chinese medicine and traditional Chinese medicine (TCM) evaluation systems to evaluate the efficacy and safety of CLD granules in the treatment of seasonal influenza. METHODS AND ANALYSIS: The study is designed as a multicentre, randomised, double-blinded, double-simulation, oseltamivir-controlled and placebo-controlled, parallel-design clinical trial. Eligible subjects (n=318) will be allocated after satisfying the criteria (Western medicine). Subjects will be randomised to receive CLD granules, oseltamivir, or a placebo for 5 days of treatment and with follow-up after treatment to record symptoms and signs and to collect pharyngeal/throat swabs and serum samples for detecting the virus and antibodies. At the same time, the syndrome differentiation criteria of TCM, such as tongue body, furred tongue and type of pulse, will be recorded as determined by doctors of both Western and Chinese medicine. Participants will be instructed to comply with the protocol and to keep a daily record of symptoms. The primary and secondary outcomes and safety indicators will be used to evaluate the efficacy and safety of CLD granules in the treatment of seasonal influenza based on both Western Chinese medicine and TCM evaluation systems. ETHICS AND DISSEMINATION: The CLD granules clinical trial will be conducted in accordance with the Declaration of Helsinki and Good Clinical Practice and has been approved by the Ethics Committee of the First Affiliated Hospital of Guangzhou Medical University. All participants must provide written informed consent. The results obtained will be disseminated at international medical conferences and in peer-reviewed publications. TRIAL REGISTRATION NUMBER: NCT02662426; Pre-results.

Novel nor-monoterpenoid indole alkaloids inhibiting glioma stem cells from fruits of Alstonia scholaris.

BACKGROUND: Glioblastoma multiforme (GBM) is a highly aggressive and frequently recurrent malignant brain tumor, and to date, the clinically effective drugs against GBM remain scarce. Natural products play an important role in drug discovery, and might be the resource of antitumor agents for GSCs. Alstonia scholaris (L.) R. Br. is rich in monoterpenoid indole alkaloids (MIAs) and used extensively for treatment of tumor in the traditional medicine system of Asia. PURPOSE: To search for new MIAs with antitumor activity against glioma stem cells from clinical patients and explore their mechanism. METHODS: Compounds were obtained from the fruits of A. scholaris by chromatographic separation, including silica gel, Sephadex LH-20 and recrystallization. Their structures were elucidated by the use of UV, IR, NMR and MS spectra. The antitumor activity of the compounds against the glioma stem cells (GSC-3#, GSC-12#, GSC-18#) were investigated by phenotypic screening and MTS assays. Cell proliferation assay by BrdU immunofluorescence staining, and apoptosis assay by cleaved-caspase-3 immunofluorescence staining and real-time PCR assay. The soft-agar clonal formation assay was performed to determine the antitumor efficacy of the compounds in vitro. RESULTS: Two new nor-monoterpenoid indole alkaloids were isolated from the fruits of A. scholaris. They exhibited selective antitumor activity against glioma stem cells (GSC-3#, GSC-12#, GSC-18#) with IC50 values of 15-25 µg/ml. Furthermore, they inhibited GSCs proliferation, induced GSCs apoptosis by increasing the expression of TNF-α and cleavage of caspase-3, and significantly damaged colony forming capacity of GSCs. CONCLUSION: New nor-monoterpenoid indole alkaloids from the fruits of A. scholaris provide new type promising molecule for the selective killing of human glioma stem cells.

Efficacy of indoor air purification in treating Artemisia (mugwort) pollen allergic rhinitis: study protocol for a randomised controlled trial.

BACKGROUND: Allergic rhinitis (AR) is a worldwide health problem. Allergen avoidance is strongly recommended for AR patients. Air purification can reduce concentrations of particles in indoor air, including those of allergens. Air purifiers have been recommended by clinicians for AR patients, but few studies have focused on the removal of airborne allergens from home environments. Such studies have been limited by a lack of blinding, small samples, or a failure to measure allergen levels, disease activity, or a combination of these factors. This study investigates the efficacy of a high-efficiency air purifier in reducing disease activity in the homes of AR patients sensitive to the allergens produced by Artemisia (mugwort) pollen. METHODS: This is a randomized, double-blind, clinical controlled trial that will test active and inactive versions of an air purifier (Atmosphere®; Amway China). Sixty AR patients sensitive to the allergens produced by Artemisia pollen will be assigned randomly to two groups of equal numbers. All patients will undergo a 4-week treatment period and a 4-week observation period. Evaluation will be conducted at baseline (day 0) and on days 7, 14, 21, 28, and 56. The primary outcome measure will be the difference in visual analog scale scores from baseline. Secondary outcomes will be changes from baseline in nasal symptoms, allergy symptom scores, responses to the Rhinoconjunctivitis Quality of Life Questionnaire, Epworth Sleepiness Scale scores, and tolerability scores for the air purifier. Side effects of treatment will be recorded. DISCUSSION: Reducing exposure to allergens can reduce the risk of conditions such as AR. We hypothesise that AR patients sensitive to the allergens produced by Artemisia pollen will not suffer symptoms in a pollen-free environment. AR patients can remove pollen from their homes using air purifiers, decreasing the risk of symptoms. We expect that our study results will provide reliable evidence for determining the effects of air-purification therapy. TRIAL REGISTRATION: ChiCTR-INR-17012481 . (Retrospectively registered 26 August 2017).

Effects of indole alkaloids from leaf of Alstonia scholaris on post-infectious cough in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Leaf of Alstonia scholaris (L.) R. Br. (Apocynaceae), a wide used ethic-medicine in many Asia and Africa counties, has also been recorded as the common traditional Chinese medicine for treatment of illnesses in respiratory system by Dai people. AIM OF THE STUDY: To provide experimental data of clinical adaption of total indole alkaloids (TA) from leaf of A. scholaris for treating post-infectious cough in phase II clinical trial. MATERIALS AND METHODS: To model post-infectious cough, all animals except control group were instilled intra-tracheal with lipopolysaccharide (LPS) (80 µg/50 µL/mouse), followed by subsequent exposure to cigarette smoke (CS) for 30 min per day for a total of 30 days. Mice were orally given TA at dose of 10, 25, 50 mg/kg, and four main alkaloids (Sch: scholaricine, Epi: 19-epischolaricine, Val: vallesamine, Pic: picrinine) once daily. Cellular infiltration was assessed in the broncho-alveolar lavage fluid (BALF). Expression of interleukin-6 (IL-6) and C-reactive protein (CRP) in the serum was determined, the superoxide dismutase (SOD) activity as well as malondialdehyde (MDA) content in the serum and homogenate were examined. Finally, histopathological examination in the lungs was assessed by H. E. staining. RESULTS: After administration of TA and four major alkaloids respectively, the symptoms of cough in mice were obviously attenuated. Total white blood cells (WBC) and neutrophils (NEU) amounts in BALF were reduced obviously and the pathological damage of lung was also attenuated. There was also significant reduction in IL-6, CRP, MDA and a marked improvement in SOD. CONCLUSIONS: The efficacy of indole alkaloids against post-infectious cough (PIC) was shown in the down-regulation of inflammatory cells, cytokines, and the balance of antioxidants. What's more, the pharmacological effects of TA were better than single indole alkaloid, which might be related to the synergic effect of four major alkaloids.

Efficacy and safety of Ban-Lan-Gen granules in the treatment of seasonal influenza: study protocol for a randomized controlled trial.

BACKGROUND: Ban-Lan-Gen (BLG) is a traditional Chinese herbal medicine. It has been used for the prevention and treatment of virus-related respiratory diseases such as influenza virus infection. BLG contains some antiviral compounds, but few evidence-based clinical studies have been conducted to assess its efficacy against influenza. We assessed the effects of BLG (including efficacy and safety) on the treatment of seasonal influenza in an evidence-based clinical trial. METHODS/DESIGN: We conducted a randomized, double-blinded, oseltamivir- and placebo-controlled, parallel-design clinical trial. A total of 177 subjects are going to be recruited after satisfying the criteria: (i) 18 to 65 years of age; (ii) illness onset within 36 h; (3) axillary temperature ≥38.0°C; and (iv) positive influenza (type A/B) virus test. Subjects will be assigned randomly into three groups in equal proportions: oseltamivir treatment, BLG granule treatment, and placebo treatment. Each group receives 5-day treatment and is followed up 1, 3, 5, 7 and 21 days later. Symptoms and patient compliance are recorded, and virus/serum viral antibodies tested. We will use the primary outcome, secondary outcome, and safety indicators to evaluate the efficacy and safety of BLG granules in the treatment of seasonal influenza. DISCUSSION: We have described the first clinical trial for treatment using a single herb against influenza A and B viruses in China. We will hold a large-scale clinical trial to comprehensively evaluate the effectiveness and safety of BLG against influenza infection based on the results of this pilot study. And this clinical trial will serve as an example for the study of other traditional herbal medicines in evidence-based clinical trials. TRIAL REGISTRATION: This study has been registered at ClinicalTrials.gov: NCT02232945 (3 September 2014).

[Effect of Yunnan herb Laggera pterodonta against influenza A (H1N1) virus in vitro].

Laggera pterodonta is commonly used for treating influenza in Southwest China, especially in Yunnnan province. The main clinical effects of L. pterodonta include anti-influenza, anti-microbial, anti-inflammatory. To investigate the anti-influenza A (H1N1) virus effect of L. pterodonta, neutralization inhibition and proliferation inhibition tests were performed. MDCK culture method was used to observe the cytopathic effect (CPE) of extracts from L. pterodonta in inhibiting influenza A (H1N1) virus and haemagglutination titre of H1N1 virus in vitro. The culture medium were collected at 24 h, 48 h, 72 h, 96 h, and detected by Real time RT-PCR, in order to compare the effect of different extracts from L. pterodonta on in vitro proliferation of H1N1, virus. The result of neutralization inhibition test showed that hemagglutination titer of ethyl acetate extract were 8 times lower at 72 h; in proliferation inhibition test, hemagglutination titer of ethyl acetate extracts reduced by 2 and 4 times. According to the results of Real time RT-PCR test, the H1N1 inhibition ratio of ethyl acetate extract was 72.5%, while the proliferation inhibition ratio of ethyl acetate extract was 25.3%; as for petroleum ether extracts, the H1N1 inhibition ratio was 60.2%, while the proliferation inhibition ratio was 81.4%. In conclusion, both ethyl acetate extract and petroleum ether extract of L. pterodonta have significant neutralization and direct proliferation inhibition effects on influenza A virus.

Comparison of in vitro antiviral activity of tea polyphenols against influenza A and B viruses and structure-activity relationship analysis.

Influenza poses a particular risk of severe outcomes in the elderly, the very young and those with underlying diseases. Tea polyphenols are the natural phenolic compounds in teas, and principally consist of catechins, proanthocyanidins, flavonols, and theaflavins, which antiviral activities have been reported recently. This study is to gain a further insight into potential of various tea polyphenols for inhibiting influenza virus infection. Five tea polyphenols exhibited inhibitory activity against influenza A virus in the trend of theaflavin>procyanidin B-2>procyanidin B-2 digallate>(-)-epigallocatechin(EGC)>(-)-epigallocatechingallate(EGCG) with IC50 values in the range of 16.2-56.5 µg/ml. Six of the tested compounds showed anti-influenza B virus activity in the order of kaempferol>EGCG>procyanidin B-2>(-)-EGC~methylated EGC>theaflavin with IC50 values in the range of 9.0-49.7 µg/ml. Based on these results, the structure-activity relationship (SAR) was explained as follows. First, the dimeric molecules, such as theaflavin and procyanidin B-2, generally displayed more potent antiviral activity against both influenza A and B viruses than the catechin monomers. Second, the kaempferol for inhibition of influenza B virus indicated that the more planar flavonol structure with only one C-4' phenolic hydroxyl group in the B ring is necessary for the anti-influenza B virus activity. A similar SAR can be drawn from the assays of another enveloped RNA virus, such as respiratory syncytial virus. These results are expected to provide guides for rational design of antiviral drugs based on polyphenols.

Nobiletin, a polymethoxylated flavonoid from citrus, shows anti-angiogenic activity in a zebrafish in vivo model and HUVEC in vitro model.

Traditional Chinese medicinal herbs are a rich source of compounds with reported anti-inflammatory and anti-carcinogenic effects. Growing evidence shows the codependence of chronic inflammation and angiogenesis, and the potential benefits of targeting angiogenesis in the treatment of chronic inflammation and targeting inflammation in the treatment of diseases with impaired angiogenesis. We hypothesized that the anti-inflammatory activity of the natural compounds may owe at least some of its efficacy to their anti-angiogenic activity and hence we investigated the anti-angiogenic activity of these compounds in vivo in zebrafish embryos and in vitro in human umbilical vein endothelial cells (HUVECs). Nobiletin, a polymethoxylated flavonoid from citrus fruits, showed anti-angiogenic activity in both assays. Nobiletin inhibited the formation of intersegmental vessels (ISVs) in live transgenic zebrafish embryos expressing green fluorescent protein (GFP) in the vasculature. Cell cycle analysis of dissociated zebrafish embryo cells showed that nobiletin induced G0/G1 phase accumulation in a dose-dependent manner in GFP-positive endothelial cells. Nobiletin also dose-dependently induced VEGF-A mRNA expression. In HUVECs, nobiletin inhibited endothelial cell proliferation and, to a greater extent, tube formation in a dose-dependent manner. As in the in vivo study, nobiletin induced G0/G1 cell cycle arrest in HUVECs. However, this arrest was not accompanied by an increase in apoptosis, indicating a cytostatic effect of nobiletin. This study, for the first time, identifies nobiletin as having potent anti-angiogenic activity and suggests that nobiletin has a great potential for future research and development as a cytostatic anti-proliferative agent.

[The effects of a hot water soluble extract (S-03) isolated from Isatis indigotica root on influenza A and B viruses in vitro].

This study was to investigate the antiviral effects of a hot water soluble extract S-03 isolated from Isatis indigotica root on different subtypes of influenza A and B viruses in MDCK cell cultures, using plaque reduction, immunofluorescence and hemo-agglutination inhibition (HAD) assays. Chemical analysis of the extract S-03 showed that it contained high proportion of polysaccharides. The antiviral effects in vitro showed that the S-03 had no effect on different influenza viruses if the drug was used before virus adsorption, but S-03 showed obvious activities against influenza viruses if treatment after virus adsorption or direct reaction of drug and virus before virus adsorption. Hemagglutination inhibition assay showed that S-03 inhibited HA activities of different human influenza viruses (inhibition concentration ranged from 3.12 to 25 mg/mL), avain influenza viruses (inhibition concentration ranged from 25 to 50 mg/mL). The antiviral effects of S-03 on different influenza A and B viruses in vitro might be through the inhibition of the HA to prevent infection.

[In vitro experimental study on the effect of resveratrol against several kinds of respiroviruses].

OBJECTIVE: To observe the cytopathogenic inhibitory effect of resveratrol on vary respiroviruses and explore the mechanism of resveratrol against viruses. METHODS: MDCK, A549, HEp-2 cell and MRC-5 were infected with Influenza virus type A FM1 strain, rhinovirus type R14, RS virus, AD virus type 7 separately, and the antiviral activity of resveratrol were observed. RESULTS: Resveratrol significantly inhibited cytopathogenic effect of AD virus type 7 at the concentration 120 microg/ml. No significant cytopathogenic effect of Resveratrol inhibiting Influenza virus type A FM1 strain, Rhinovirus type R14, RS virus on separate cells was observed. CONCLUSION: It is concluded that resveratrol is effective on inhibiting AD virus type 7 in vitro, however, its mechanism is needed for further study.