Expression of antiviral cytokines in Crandell-Reese feline kidney cells pretreated with Korean red ginseng extract or ginsenosides

Antiviral effects of Korean Red Ginseng on human coronavirus OC43

Background

Panax ginseng Meyer is a medicinal plant well-known for its antiviral activities against various viruses, but its antiviral effect on coronavirus has not yet been studied thoroughly. The antiviral activity of Korean Red Ginseng (KRG) and ten ginsenosides against Human coronavirus OC43 (HCoV-OC43) was investigated in vitro.

Methods

The antiviral response and mechanism of action of KRG extract and ginsenoside Rc, Re, Rf, Rg1, Rg2-20 (R) and -20 (S), Rg3-20 (R) and -20 (S), and Rh2-20 (R) and -20 (S), against the human coronavirus strain OC43 were investigated by using plaque assay, time of addition assay, real-time PCR, and FACS analysis.

Results

Virus plaque formation was reduced in KRG extract-treated and HCoV-OC43-infected HCT-8 cells. KRG extract decreased the viral proteins (Nucleocapsid protein and Spike protein) and mRNA (N and M gene) expression, while increased the expression of interferon genes.

Conclusion

KRG extract exhibits antiviral activity by enhancing the expression of interferons and can be used in treating infections caused by HCoV-OC43.

Immunomodulators Containing Epicor, Colostrum, Vitamin D, Zinc, Lactobacilli and Bifidobacterium Reduce Respiratory Exacerbations in Children and Adults with Chronic Pulmonary Diseases

(1) Background: A number of studies have demonstrated the connection between developing or exacerbating chronic respiratory diseases in adults and children. However, still, few studies focus on reducing exacerbations via immunomodulation. (2) Methods: In this pilot study, a total of 25 pediatric and adult patients with bronchial asthma (BA) and chronic obstructive pulmonary disease (COPD)/persistent bacterial bronchitis (PBB) were included, administered over-the-counter (OTC) immunomodulators and followed up for 6 or 12 months. (3) Results: We observed a decrease in the frequency of exacerbations with slight improvements in functional respiratory indicators in adults on their second and third visits and a reduced number of exacerbations and improved spirometry indices in children with BA, although exacerbations requiring hospital admission remained at a similar rate. (4) Conclusions: We confirmed that the number of exacerbations of underlying chronic respiratory disease in adults and children could be reduced after the administration of OTC immunomodulators, probably by optimizing the immune resistance to common viral infections.

Ginsenoside Rb1 is an immune-stimulatory agent with antiviral activity against enterovirus 71

ETHNOPHARMACOLOGICAL RELEVANCE

According to the theory of traditional Chinese medicine, the main pathogenesis of severe hand, foot and mouth disease (HFMD) is that the heat and wet poisons are deeply trapped in the viscera, which causes the deficiency of Qi and Yin in the patient's body. Ginsenoside Rb1 (Rb1) is the most abundant triterpenoid saponin in Panax quinquefolius L., which has the function of Qi-invigorating and Yin-nourishing. Enterovirus 71 (EV71) is one of the causative pathogens of HFMD, especially the form associated with some lethal complications. Therefore, the therapeutic effect of Rb1 on this disease caused by EV71 infection is worth exploring.

AIM OF THE STUDY

We explored the effective antiviral activities of Rb1 against EV71 in vitro and in vivo and investigated its preliminary antiviral mechanisms.

MATERIAL AND METHODS

EV71-infected two-day-old suckling mice model was employed to detect the antiviral effects of Rb1 in vivo. To detect the antiviral effects of Rb1 in vitro, cytopathic effect (CPE) reduction assay was performed in EV71-infected Rhabdomyosarcoma (RD) cells. Interferon (IFN)-β interference experiment was employed to detect the antiviral mechanism of Rb1.

RESULTS

In this paper, we first found that Rb1 exhibited strong antiviral activities in EV71-infected suckling mice when compared to those of ribavirin. Administration of Rb1 reduced the CPE of EV71-infected RD cells in a dose-dependent manner. Moreover, EV71-induced viral protein-1 (VP-1) expression was significantly reduced by Rb1 administration in vitro and in vivo. Furthermore, Rb1 treatment could induce high cellular and humoral immune responses in vivo. Meanwhile, Rb1 contributed to the enhanced Type I IFN responses and IFN-β knockdown reversed the antiviral activity of Rb1 in vitro.

CONCLUSION

In summary, our findings suggest that Rb1 is an immune-stimulatory agent and provide an insight into therapeutic potentials of Rb1 for the treatment of EV71 infection.

A randomized, double-blind, placebo-controlled pilot study to assess the effects of protopanaxadiol saponin-enriched ginseng extract and pectinase-processed ginseng extract on the prevention of acute respiratory illness in healthy people

Background

GS-3K8 and GINST, both of which are modified ginseng extracts, have never been examined in terms of their effectiveness for the prevention of acute respiratory illness (ARI) in humans. We conducted a pilot study to assess the feasibility of performing a large-scale, randomized, controlled trial.

Methods

This study was a randomized, double-blind, placebo-controlled, pilot study at a single center from October 2014 to March 2015. The 45 healthy applicants were randomly divided into the GS-3K8 (n = 15), GINST (n = 15), and placebo groups (n = 15). The study drug was administered as a capsule (500 mg/cap and 3000 mg/day). GS-3K8 contained 6.31 mg/g of Rg1, 15.05 mg/g of Re, 30.84 mg/g of Rb1, 15.02 mg/g of Rc, 12.44 mg/g of Rb2, 6.97 mg/g of Rd, 1.59 mg/g of Rg3, 3.25 mg/g of Rk1, and 4.84 mg/g of Rg5. GINST contained 7.54 mg/g of Rg1, 1.87 mg/g of Re, 5.42 mg/g of Rb1, 0.29 mg/g of Rc, 0.36 mg/g of Rb2, 0.70 mg/g of Rd, and 6.3 mg/g of compound K. The feasibility criteria were the rates of recruitment, drug compliance, and successful follow-up. The primary clinical outcome measure was the incidence of ARI. The secondary clinical outcome measures were the duration of symptoms.

Results

The rate of recruitment was 11.3 participants per week. The overall rate of completed follow-up was 97.8%. The mean compliance rate was 91.64 ± 9.80%, 95.28 ± 5.75%, and 89.70 ± 8.99% in the GS-3K8, GINST, and placebo groups, respectively. The incidence of ARI was 64.3% (9/14; 95% confidence interval [CI], 31.4-91.1%), 26.7% (4/15; 95% CI, 4.3-49.0%), and 80.0% (12/15; 95% CI, 54.8-93.0%) in the GS-3K8, GINST, and placebo groups, respectively. The average days of symptoms were 3.89 ± 4.65, 9.25 ± 7.63, and 12.25 ± 12.69 in the GS-3K8, GINST, and placebo groups, respectively.

Conclusion

The results support the feasibility of a full-scale trial. GS-3K8 and GINST appear to have a positive tendency toward preventing the development of ARI and reducing the symptom duration. A randomized controlled trial is needed to confirm these findings.

Interferon-omega: Current status in clinical applications

Since 1985, interferon (IFN)-ω, a type I IFN, has been identified in many animals, but not canines and mice. It has been demonstrated to have antiviral, anti-proliferation, and antitumor activities that are similar to those of IFN-α. To date, IFN-ω has been explored as a treatment option for some diseases or viral infections in humans and other animals. Studies have revealed that human IFN-ω displays antitumor activities in some models of human cancer cells and that it can be used to diagnose some diseases. While recombinant feline IFN-ω has been licensed in several countries for treating canine parvovirus, feline leukemia virus, and feline immunodeficiency virus infections, it also exhibits a certain efficacy when used to treat other viral infections or diseases. This review examines the known biological activity of IFN-ω and its clinical applications. We expect that the information provided in this review will stimulate further studies of IFN-ω as a therapeutic agent.

Inhibitory mechanism of five natural flavonoids against murine norovirus

BACKGROUND

Human noroviruses (HuNoV), which are responsible for acute gastroenteritis, are becoming a serious public health concern worldwide. Since no effective antiviral drug or vaccine for HuNoV has been developed yet, some natural extracts and their active components have been investigated for their ability to inhibit noroviruses. However, their exact antiviral mechanisms have not been investigated.

PURPOSE

This study was performed to investigate the expression of interferon (IFN)-α, IFN-λ, tumor necrosis factor-α (TNF-α), Mx, and zinc finger CCCH type antiviral protein 1 (ZAP), 2'-5' oligo (A) synthetase (OAS), and inducible nitric oxide synthase (iNOS) in RAW 264.7 cells pre-treated with fisetin, daidzein, quercetin, epigallocatechin gallate (EGCG), and epicatechin gallate (ECG) that have anti-noroviral activity.

STUDY DESIGN

Based on the antiviral activity of the five flavonoids, recently reported by our group, the expression of antiviral factors such as IFN-α, IFN-λ, TNF-α, IL-1β, IL-6, Mx, ZAP, OAS, and iNOS was investigated in RAW 264.7 cells pre-treated with these flavonoids.

METHODS

Anti-noroviral effect was determined by performing a plaque assay on cells treated with the flavonoid. RAW 264.7 cells were treated with fisetin, daidzein, quercetin, EGCG, and ECG. Then, mRNA of IFN-α, IFN-λ, TNF-α, IL-1β, IL-6, Mx, ZAP, OAS, and iNOS were measured by real-time RT-PCR. IFN-α, TNF-α, IL-1β, and IL-6 proteins were measured by ELISA.

RESULTS

Pre-treatment with fisetin (50μM), fisetin (100μM), EGCG (100μM), quercetin (100μM), daidzein (50μM), and ECG (150μM) significantly reduced MNoV by 50.00±7.14 to 60.67±9.26%. The mRNA levels of IFN-α, IFN-λ, TNF-α, Mx, and ZAP were upregulated in RAW 264.7 cells pre-treated with fisetin, quercetin, and daidzein, but not in those pre-treated with EGCG or ECG. Regarding protein levels, IFN-α was significantly induced in cells pre-treated with fisetin, quercetin, and daidzein, whereas TNF-α was significantly induced only in cells pre-treated with daidzein.

CONCLUSION

Pre-treatment of RAW 264.7 cells with the five flavonoids inhibited MNoV by upregulating the expression of antiviral cytokines (IFN-α, IFN-λ, and TNF-α) and interferon-stimulating genes (Mx and ZAP).

The immune-enhancing activity of Cervus nippon mantchuricus extract (NGE) in RAW264.7 macrophage cells and immunosuppressed mice

Chemotherapeutics are often used to inhibit the proliferation of cancer cells. However, they can also harm healthy cells and cause side effects such as immunosuppression. Especially traditional oriental medicines long used in Asia, may be beneficial candidates for the alleviation of immune diseases. Cervus nippon mantchuricus extract (NGE) is currently sold in the market as coffee and health drinks. However, NGE was not widely investigated and efficacy remain unclear and essentially nothing is known about their potential immune-regulatory properties. As a result, NGE induced the differentiation of RAW264.7 macrophage cells. NGE-stimulated RAW264.7 macrophage cells elevated cytokines levels and NO production. NGE-stimulated RAW264.7 macrophage cells activated MAPKs and NF-κB signaling pathways. NGE encouraged the immuno-enhancing effects in immunosuppressed short-term treated with NGE mice model. NGE or Red ginseng encouraged the immuno-enhancing effects in immunosuppressed long-term treated with NGE mice model. Our data clearly show that NGE contains immune-enhancing activity and can be used to treat immunodeficiency.

Inhibition of Murine Norovirus and Feline Calicivirus by Edible Herbal Extracts

Human noroviruses (HuNoVs) cause foodborne and waterborne viral gastroenteritis worldwide. Because HuNoV culture systems have not been developed thus far, no available medicines or vaccines preventing infection with HuNoVs exist. Some herbal extracts were considered as phytomedicines because of their bioactive components. In this study, the inhibitory effects of 29 edible herbal extracts against the norovirus surrogates murine norovirus (MNV) and feline calicivirus (FCV) were examined. FCV was significantly inhibited to 86.89 ± 2.01 and 48.71 ± 7.38% by 100 μg/mL of Camellia sinensis and Ficus carica, respectively. Similarly, ribavirin at a concentration of 100 μM significantly reduced the titer of FCV by 77.69 ± 10.40%. Pleuropterus multiflorus (20 μg/mL) showed antiviral activity of 53.33 ± 5.77, and 50.00 ± 16.67% inhibition was observed after treatment with 20 μg/mL of Alnus japonica. MNV was inhibited with ribavirin by 59.22 ± 16.28% at a concentration of 100 μM. Interestingly, MNV was significantly inhibited with 150 µg/mL Inonotus obliquus and 50 μg/mL Crataegus pinnatifida by 91.67 ± 5.05 and 57.66 ± 3.36%, respectively. Treatment with 20 µg/mL Coriandrum sativum slightly reduced MNV by 45.24 ± 4.12%. The seven herbal extracts of C. sinensis, F. carica, P. multiflorus, A. japonica, I. obliquus, C. pinnatifida, and C. sativum may have the potential to control noroviruses without cytotoxicity.

Antiviral activity of 20(R)-ginsenoside Rh2 against murine gammaherpesvirus

Background

Ginsenosides are the major components of Panax ginseng Meyer, an herbal medicine used for the treatment of various diseases. Different ginsenosides contribute to the biological properties of ginseng, such as antimicrobial, anticancer, and immunomodulatory properties. In this study, we investigated the antiviral effects of 15 ginsenosides and compound K on gammaherpesvirus.

Methods

The antiviral activity of ginsenosides was examined using the plaque-forming assay and by analyzing the expression of the lytic gene.

Results

20(R)-Ginsenoside Rh2 inhibited the replication and proliferation of murine gammaherpesvirus 68 (MHV-68), and its half-maximal inhibitory concentration (IC₅₀) against MHV-68 was estimated to be 2.77 μM. In addition, 20(R)-ginsenoside Rh2 inhibited 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced lytic replication of human gammaherpesvirus in the Kaposi's sarcoma-associated herpesvirus (KSHV)-positive cell line BC3.

Conclusion

Our results indicate that 20(R)-ginsenoside Rh2 can inhibit the replication of mouse and human gammaherpesviruses, and thus, has the potential to treat gammaherpesvirus infection.

Characterization of the inhibitory effect of an extract of Prunella vulgaris on Ebola virus glycoprotein (GP)-mediated virus entry and infection

Currently, no approved antiviral therapeutic is available for treatment or prevention of Ebola virus (EBOV) infection. In this study, we characterized an EBOV-glycoprotein (GP) pseudotyped HIV-1-based vector system in different cell cultures, including human umbilical vein endothelial cells (HUVECs) and human macrophages, for the screening of anti-EBOV-GP agent(s). Based on this system, we demonstrated that an aqueous extract (CHPV) from the Chinese herb Prunella vulgaris displayed a potent inhibitory effect on EBOV-GP pseudotyped virus (EBOV-GP-V)-mediated infection in various cell lines, including HUVEC and macrophage. In addition, our results indicated that CHPV was able to block an eGFP-expressing Zaire ebola virus (eGFP-ZEBOV) infection in VeroE6 cells. The anti-EBOV activity of CHPV was exhibited in a dose-dependent manner. At a 12.5 μg/ml concentration, the CHPV showed a greater than 80% inhibition of EBOV-GP-V and eGFP-EBOV infections. Likewise, our studies suggested that the inhibitory effect of CHPV occurred by binding directly to EBOV-GP-Vs and blocking the early viral events. Interestingly, our results have shown that CHPV was able to enhance the anti-EBOV activity of the monoclonal antibody MAb 2G4 against EBOV-GP. Overall, this study provides evidence that CHPV has anti-EBOV activity and may be developed as a novel antiviral approach against EBOV infection.

Ginseng, the natural effectual antiviral: Protective effects of Korean Red Ginseng against viral infection

Korean Red Ginseng (KRG) is a heat-processed ginseng developed by the repeated steaming and air-drying of fresh ginseng. Compared with fresh ginseng, KRG has been shown to possess greater pharmacological activities and stability because of changes that occur in its chemical constituents during the steaming process. In addition to anticancer, anti-inflammatory, and immune-modulatory activities, KRG and its purified components have also been shown to possess protective effects against microbial infections. Here, we summarize the current knowledge on the properties of KRG and its components on infections with human pathogenic viruses such as respiratory syncytial virus, rhinovirus, influenza virus, human immunodeficiency virus, human herpes virus, hepatitis virus, norovirus, rotavirus, enterovirus, and coxsackievirus. Additionally, the therapeutic potential of KRG as an antiviral and vaccine adjuvant is discussed.