Effects of Guiqi Polysaccharide on Telomerase Activity in Premature Senescence WI-38 Cells / 中国中医药信息杂志

Objective To investigate the effects of Guiqi polysaccharide (GQP) on the telomerase activity in premature senescence of WI-38 cells;To discuss its mechanism of action.Methods MTT assay was used to observe the effects of different concentrations of H2O2 on the proliferation of WI-38 cells and screened the best concentration of H2O2 to induce premature senescence cellular model in WI-38 cells. ELISA and chemical staining method were used to evaluate the protection of GQP in telomerase activity and senescence-associated β-galactosidase activity in premature cellular senescence.Results 200μmol/L H2O2 treatment could induce premature senescence in WI-38 cells. There were no significant differences in senescence-associated β-galactosidase and telomerase activity between GQP group and normal control group (P>0.05), but had significant difference with model group (P<0.01).Conclusion GQP can increase the telomerase activity and inhibit the senescence-associated β-galactosidase activity in premature senescence of WI-38 cells.

Therapeutic efficacy of Hypericum perforatum L. extract for mice infected with an influenza A virus.

Hypericum perforatum L., a plant used in Chinese herbal medicine, has been proven effective against many viral diseases. In the present study, the therapeutic efficacy of an extract of H. perforatum (HPE) against influenza A virus (IAV) was investigated in mice. Whether HPE would be a promising agent for influenza treatment was evaluated by measuring the protection rate, mean survival days, lung index, and viral titer, as well as the secretion of IL-6, interleukin-10 (IL-10), tumour necrosis factor-α (TNF-α), and interferon-gamma (IFN-γ) in lung tissue and serum on days 3 and 5 post-infection. The results showed that HPE could reduce the lung index and viral titer of mice infected with IAV, decrease mortality, and prolong the mean survival time. HPE decreased the concentration of IL-6 and TNF-α in lung tissue and serum on day 5 post-infection. In contrast, HPE enhanced the lung and serum levels of IL-10 and IFN-γ on the days 3 and 5 post-infection. Our study indicates that HPE has significant therapeutic efficacy for mice infected with IAV. The possible reasons for these results were concluded to be pertaining to up-regulating the expression of IL-10 and IFN-γ, and down-regulating the secretion of IL-6 and TNF-α in lung and serum.

Anti-Influenza A Virus Effect of Hypericum perforatum L. Extract / 中国病毒学·英文版

To study the antiviral effect of Hypericum perforatum L. extract (HPE) on influenza A virus (IAV) (H1N1) in vitro and in vivo. Cytopathic effect (CPE) and neutral red (NR) dye uptake were used to examine the antiviral effect of HPE on Madin Darby Canine Kidney (MDCK) cells which were infected with IAV in vitro. HPE was effective against influenza A virus (IAV) in vitro, with a 50% effective concentration (EC50) of 40 μg/mL. The mean 50% cytotoxic concentration (CC50) in the MDCK used in these experiments was 1.5 mg/mL. Ribavirin was run in parallel with EC50 values of 5.0 μg/mL; the mean CC50 for ribavirin was 520 μg/mL. Oral gavage administrations of HPE or ribavirin to mice infected with the IAV were highly effective in preventing death, slowing the decline of arterial oxygen saturation, inhibiting lung consolidation and reducing lung virus titers. The minimum effective dose of HPE in these studies was 31.25 mg/kg/day, which was administered twice daily for 5 d beginning 4 h prior to virus exposure. Below a dosage of 2000 mg/kg/day, almost all treated mice survived, which suggests that HPE is of low toxicity. Ribavirin's minimum effective dose was 40 mg/kg/day with the LD50 determined to be 200 mg/kg/day. Delay of the initiation of either HPE or ribavirin therapy, using approximately 1/3 LD50 dose each time, could still be protective as late as 48 h after exposure to the IAV. While both agents appeared to have similar efficacy against IAV infections, HPE was considered to be less toxic and may warrant further evaluation as a possible therapy for influenza.