Antiviral Properties of R. tanguticum Nanoparticles on Herpes Simplex Virus Type I In Vitro and In Vivo.

Herpes simplex virus type 1 (HSV-1), an enveloped DNA virus, plays a key role in varieties of diseases including recurrent cold sores, keratoconjunctivitis, genital herpes and encephalitis in humans. Great efforts have been made in developing more effective and less side-effects anti-herpes simplex virus agents, including traditional Chinese herbal medicines. In the present study, we evaluated the antiviral efficacy of Rheum tanguticum nanoparticles against HSV-1 in vitro and in vivo. R. tanguticum nanoparticles could inactivate the HSV-1 virions and block the viral attachment and entry into cells. Time-of-addition assay indicated that R. tanguticum nanoparticles could interfere with the entire phase of viral replication. Besides, R. tanguticum nanoparticles showed the ability to inhibit the mRNA expression of HSV-1 immediate early gene ICP4 and early gene ICP8 as well as the expression of viral protein ICP4 and ICP8. Moreover, R. tanguticum nanoparticles have been proved to protect mice against HSV-1 induced lethality by decreasing the viral load and alleviated pathological changes in brain tissues. In conclusion, we demonstrated that R. tanguticum nanoparticles could inhibit HSV-1 infection through multiple mechanisms. These results suggest that R. tanguticum nanoparticles may have novel roles in the treatment of HSV-1 infection.

[Protective effects of total saponins of Panax japonicas on non-alcoholic fatty liver disease through regulating expression of miR-199-5p].

To research the effection and probable mechanism for the total saponins of Panax japonicas(TPSJ) in mice on non-alcoholic fatty liver disease. Forty SPF male Kunming mice were randomily divided into four group:control group,NAFLD group, low-dose TPSJ treated group,high-dose TPSJ treated group. High-fatty and high-frutose-diet was applied to eatablish NAFLD model，and TPSJ (100 and 200 mg·kg⁻¹) in feeding were given for the TPSJ groups for 4 weeks. To collect the serum with liver and the ALT and TC of serum were monitored after 4 weeks. The hepatic histopathologic structure was observed by haematoxylin-eosin (HE) staining, RT-PCR and RT-qPCR was applied for the detection of miR-199-5p，VEGFa，HGF，c-Met and protein expression level was detected bv laser confocal microscope.Compared with control group, the level of serum ALT and TC in the model group was higher,the liver of the model group showed that hepatocytes display obvious lipid deposition. Then TPSJ treated showed that markedly improved histopathologic changes, decreased fatty deposition. In the meantime,the expression level of miR-199-5p was significantly decreased, thus the expression of HGF and c-Met were significantly increased. TPSJ play a role of prevention on fatty liver, the machanism maybe by blocking miR-199-5p targeted to c-Met signaling pathways in NAFLD.

In vitro and in vivo studies of the inhibitory effects of emodin isolated from Polygonum cuspidatum on Coxsakievirus B4.

The lack of effective therapeutics for Coxsackievirus B4 (CVB4) infection underscores the importance of finding novel antiviral compounds. Emodin (1,3,8-trihydroxy-6-methylanthraquinone) is one of the natural anthraquinone derivatives obtained from the root and rhizome of Polygonum cuspidatum. In the present study, the possibility of using emodin as a potential antiviral to treat CVB4 infection was explored in vitro and in mice. Emodin reduced CVB4 entry and replication on Hep-2 cells in a concentration- and time-dependent manner, with a 50% effective concentration (EC50) of 12.06 µM and selectivity index (SI) of 5.08, respectively. The inhibitory effect of emodin for CVB4 entry and replication was further confirmed by a quantitative real time PCR (qPCR) assay. The results further showed that the mice orally treated with different dosages of emodin displayed a dose dependent increase of survival rate, body weight and prolonged mean time of death (MTD), accompanied by significantly decreased myocardial virus titers and pathologic scores/lesions. Moreover, emodin could inhibit CVB4-induced apoptosis in vitro and in vivo. Our results indicated that emodin could be used as potential antiviral in the post-exposure prophylaxis for CVB4 infection.

Amelioration of influenza virus-induced reactive oxygen species formation by epigallocatechin gallate derived from green tea.

AIM: To study whether epigallocatechin gallate (EGCG), a green tea-derived polyphenol, exerted anti-influenza A virus activity in vitro and in vivo. METHODS: Madin-Darby canine kidney (MDCK) cells were tested. The antiviral activity of EGCG in the cells was determined using hemagglutination assay and qPCR. Time of addition assay was performed to determine the kinetics of inhibition of influenza A by EGCG. The level of reactive oxygen species (ROS) were determined with confocal microscopy and flow cytometry. BALB/c mice were treated with EGCG (10, 20 or 40 mg·kg(-1)·d(-1), po) for 5 d. On the 3rd d of the treatment, the mice were infected with influenza A virus. Histopathological changes, lung index and virus titers in the lungs were determined. RESULTS: Treatment of influenza A-infected MDCK cells with EGCG (1.25-100 nmol/L) inhibited influenza A replication in a concentration-dependent manner (the ED(50) value was 8.71±1.11 nmol/L). Treatment with EGCG (20 nmol/L) significantly suppressed the increased ROS level in MDCK cells following influenza A infection. In BALB/c mice infected with influenza virus, oral administration of EGCG (40 mg·kg(-1)·d(-1)) dramatically improved the survival rate, decreased the mean virus yields and mitigated viral pneumonia in the lungs, which was equivalent to oral administration of oseltamivir (40 mg·kg(-1)·d(-1)), a positive control drug. CONCLUSION: The results provide a molecular basis for development of EGCG as a novel and safe chemopreventive agent for influenza A infection.

The inhibitory effect of Rheum palmatum against coxsackievirus B3 in vitro and in vivo.

Coxsackievirus B(3)(CVB(3)) infection is the major cause of viral myocarditis, as well as dilated cardiomypathy. Rhubarb is one of the oldest and best-known traditional Chinese medicines. We initiated this study to determine the antiviral effect of an ethanol extract from the roots and rhizoma of Rheum palmatum (R. palmatum, one of the Chinese Rhubarbs), against CVB(3) in tissue culture cells and in a mouse model. The ethanol extract from R. palmatum showed significant inhibitory activity against CVB(3) on HEp-2 cells when added after infection, with IC(50) of 4 µg/ml, TI of 10. The medicated mouse serum still contained the pharmaceutical compound 24 h after intraperitoneal injection, and exhibited an antiviral effect on CVB(3)-infected cells, especially in the 0.3 and 0.5 g/kg/day treatment groups. Furthermore, the CVB(3)-infected mice were treated with the extract solution with dosages of 0.3 g/kg/day beginning 24 h post-CVB(3) exposures. The ethanol extract treated mice showed alleviated clinical signs, better survival rate, prolonged MTD and decreased viral titers compared to the virus control group. Our results indicate that the ethanol extract from R. palmatum has the anti-CVB(3) activity in vitro and in vivo and thus provides a re-evaluation of this old remedy with a broad therapeutic potential.

The effect of emodin, an anthraquinone derivative extracted from the roots of Rheum tanguticum, against herpes simplex virus in vitro and in vivo.

AIM OF THE STUDY: Herpes simplex viruses (HSV-1 and -2) are important pathogens for humans and the discovery of novel anti-HSV drugs with low toxicity deserves great efforts. Rhubarb is one of the oldest and best-known traditional Chinese medicines. We initiated this study to test if emodin is the active ingredients from Rheum tanguticum (R. tanguticum, one of the Chinese Rhubarb) against HSV infection and to investigate its antiviral activity on HSV infection in tissue culture cells and in a mouse model. MATERIALS AND METHODS: Emodin (3-methyl-1,6,8-trihydroxyanthraquinone) was extracted and purified from R. tanguticum (cultivated at high mountainous area in Qinghai) and the purity was determined by high performance liquid chromatography. The antiviral experiments of emodin against HSV infection were performed in vitro and in vivo. In vivo, the HSV-infected mice were orally administered with emodin beginning at 24 h post-HSV exposures with dosages of 3.3 g/kg/day, 6.7 g/kg/day, and 11.3 g/kg/day, respectively, for 7 days. RESULTS: Emodin was found to inhibit the replication of HSV-1 and HSV-2 in cell culture at the concentration of 50 µg/ml with antiviral index of 2.07 and 3.53, respectively. The emodin treatment increased the survival rate of HSV-infected mice, prolonged survival time and showed higher efficacy of HSV elimination from brain, heart, liver and ganglion, compared to the viral controls. In addition, the antiviral activity of emodin was found to be equivalent to that of acyclovir in vivo. CONCLUSIONS: Our results indicate that emodin has the anti-HSV activity in vitro and in vivo and is thus a promising agent in the clinical therapy of HSV infection.