Carvacrol inhibits the excessive immune response induced by influenza virus A via suppressing viral replication and TLR/RLR pattern recognition.

ETHNOPHARMACOLOGICAL RELEVANCE: Carvacrol, a monoterpene phenol from Mosla chinensis Maxim, which is a commonly Chinese herbal medicine. The most important pharmacology of it is dispelling exogenous evils by increasing perspiration. And it is the gentleman medicine in the Chinese herbal compound prescription of Xin-Jia-Xiang-Ru-Yin, mainly for the treatment of summer colds with dampness including influenza virus A infection. AIM OF THE STUDY: Our preliminary study verified that the Xin-Jia-Xiang-Ru-Yin could inhibit acute lung injury of mice with influenza virus A infection. And there have been some reports implicating the high antimicrobial activity of carvacrol for a wide range of product preservation, but little research including the effects of it on viral infection. The aim of this study was to reveal the antiviral effects of carvacrol, the main constituent in Mosla chinensis Maxim. MATERIALS AND METHODS: Initially, C57BL/6 mice were grouped and intranasally administered FM1 virus to construct viral infection models. After treatment with ribavirin and carvacrol for 5 days, all mice were euthanized, and specimens were immediately obtained. Histology, flow cytometry and Meso Scale Discovery (MSD) analysis were used to analyze pathological changes in lung tissue, the expression levels of cytokines and the differentiation and proportion of CD4+ T cells subsets, while Western blot and qRT-PCR were used to detect the expression of related proteins and mRNA. RESULTS: Carvacrol attenuated lung tissue damage, the proportions of Th1, Th2, Th17 and Treg in CD4+ T cells and the relative proportions of Th1/Th2 and Th17/Treg cells. Carvacrol inhibited the expression of inflammation-associated cytokines including IFN-γ, IL-2, IL-4, IL-5, IL-12 and TNF-ɑ, IL-1, IL-10, IL-6. Decreased levels of TLR7, MyD88, IRAK4, TRAK6, NF-κB, RIG-I, IPS-I and IRF mRNA in carvacrol-treated mice were observed comparing to the mice in VC group. Further, the total expression of RIG-I, MyD88 and NF-κB proteins had increased significantly in the VC group but reduced obviously in the group treated with ribavirin or carvacrol. CONCLUSIONS: These results indicate that carvacrol is a potential alternative treatment for the excessive immune response induced by influenza virus A infection, the cold-fighting effect of Mosla chinensis Maxim may depend on the anti-virus of carvacrol.

Does Vitamin D Deficiency Affect the Immunogenic Responses to Influenza Vaccination? A Systematic Review and Meta-Analysis.

Influenza virus infection is a major global public health problem, and the efficacy of influenza vaccination is not satisfactory. Vitamin D is involved in many immune-mediated inflammatory processes. The impact of vitamin D levels on the immunogenic response to influenza vaccination is not clear. We performed a comprehensive literature search and systematic review of studies that investigated vitamin D and influenza vaccination. Data pertaining to study population, vaccine components, vitamin D levels, and immunogenic response were analyzed. Nine studies, with a combined study population of 2367 patients, were included in the systematic review. Four studies were included in the meta-analysis to investigate the influence of vitamin D deficiency (VDD) on the seroprotection (SP) rates and seroconversion (SC) rates following influenza vaccination. We found no significant association between vitamin D level and the immunogenic response to influenza vaccination. However, strain-specific differences may exist. We observed lower SP rates of influenza A virus subtype H3N2 (A/H3N2) and B strain in VDD patients than patients with normal vitamin D levels (A/H3N2: 71.8% vs. 80.1%, odds ratio (OR): 0.63, 95% confidence interval (CI): 0.43-0.91, p = 0.01; B strain: 69.6% vs. 76.4%, OR: 0.68, 95% CI: 0.5-0.93, p = 0.01). However, the SP rates of A/H1N1 and SC rates of all three strains were not significantly different in VDD and control groups. In conclusion, no association was observed between VDD and immunogenic response to influenza vaccination.

Antibody and cell-mediated immune response to whole virion and split virion influenza vaccine in patients with inflammatory bowel disease on maintenance immunosuppressive and biological therapy.

OBJECTIVE: Influenza vaccination is recommended for inflammatory bowel disease (IBD) patients on immunosuppressive therapy. The objective was to evaluate the antibody and cell-mediated immune response to the split and whole virion influenza vaccine in patients with IBD treated with anti-TNF-α and immunosuppressive therapy. PATIENTS AND METHODS: One hundred and fifty-six immunocompromised IBD patients were vaccinated. Fifty-three patients (control group) refused vaccination. Split virion vaccine and whole virion vaccine were used. Serum samples were obtained for pre- and postimmunization antibody titers to influenza vaccine (A/California/7/2009 [H1N1], A/Victoria/361/2011 [H3N2], B/Wisconsin/1/2010-like B/Hubei-Wujiagang/158/2009). Cell-mediated response was evaluated using an interferon (INF)-γ, interleukine (IL)-2 and tumor necrosis factor (TNF)-α ELISA. RESULTS: Postimmunization titers of both influenza subtypes increased significantly after the administration of split virion vaccines compared to the controls and to those who received whole virion vaccine. The antibody titers of Influenza B also increased significantly in patients immunized with split vaccine and treated with anti-TNF-α therapy. After influenza vaccination, the level of serum IL-2 significantly decreased. No serious side effects developed occurred after influenza vaccination, and the influenza-like symptoms did not differ significantly between vaccinated versus control patients. The relapse of the disease was observed in only 10% of the patients and was more common in vaccinated than in control subjects. CONCLUSION: Split virion vaccines seem to be more effective than whole virion vaccines. Measuring the antibody responses is worthwhile in patients treated with immunosuppressants to determine the efficacy of influenza vaccination.

Oral administration of patchouli alcohol isolated from Pogostemonis Herba augments protection against influenza viral infection in mice.

Seasonal influenza A infection results in considerable morbidity and mortality. The limited efficacy of available therapeutic strategies stresses the need for development and study of new molecules against influenza virus (IFV). Patchouli alcohol (PA), the major chemical constituent of Pogostemonis Herba, was previously found to strongly inhibit influenza H1N1 replication in vitro. In the present study, the in vivo anti-IFV effect of PA was investigated. In a mouse model infected with lethal levels of FM1, oral administration of PA (20 mg/kg to 80 mg/kg) for 7 d post IFV infection significantly increased the survival rate and survival time. For IFV infection at nonlethal levels, the quantity of IFV in the lungs 5 d after infection was significantly reduced after PA (20 mg/kg to 80 mg/kg) administration. Anti-IFV IgA, IgM, and IgG titers in serum on day 6 were significantly higher in the PA-treated group than the IFV-control group. Anti-IFV immune response augmentation was further confirmed by the elevated production of CD3+, CD4+, and CD8+ T cell levels in blood. Furthermore, the levels of inflammatory cytokines, including TNF-alpha, IL-10 and IFN-gamma in serum of mice, were regulated. Lung inflammation was reduced significantly after PA administration, and the effect may be mediated, at least in part, by regulating the lung levels of inflammatory cytokines. Thus, oral administration of PA appears to be able to augment protection against IFV infection in mice via enhancement of host immune responses, and attenuation of systemic and pulmonary inflammatory responses.

[Influence of four parts of forming of Yiqi Qingwen Jidu Heji (YQQWJDHJ) to lung inflammatory cytokines of model rats infected with influenza virus FM1].

OBJECTIVE: To observe the influence of the 4 parts of forming of Yiqi Qingwen Jidu Heji(YQQWJDHJ) to lung inflammatory cytokines of the model rats infected with influenza virus dynamically, and to discuss the mechanism of 4 parts of forming to anti-influenza immune injury and restoration. METHOD: At the different stages of infection with the model rats infected by FM1 influenza, expression in lung of TNF-alpha, IL-6, IL-1, IL-10 and IFN-gamma was detected after the intervention of 4 parts of forming using ELISA method. RESULT: The expression of TNF-alpha, IL-6, IL-1 and IFN-gamma of model rats infected by FM1 were higher than the control group, the expression of IL-10 did not change. The expression of TNF-alpha was significantly reduced in 3 to 5 days after infection. By the method of relieving superficies with acrid-cold, clearing away heat and poison and replenishing Qi, the lung expression of IFN-gamma was significantly increased in the stage after infection. The method of relieving superficies with acrid-warm significantly reduced lung expression of IL-6 after infection in 1 to 3 days and on the 7th day, decreased the expression of IL-1 in 3 to 7 days, increased IFN-gamma expression on the 3rd day and the 7th day, and significantly increased the expression of IL-10 on the 1st day and in 5 to 7 days. The method of relieving superficies with acrid-cold reduced the expresssion of IL-6 after infection, and significantly increased the expression of IL-10. It could increase the expression of IL-1 after infection on the 3rd day, but reduced IL-1 expression after infection 7 days. The method of clearing away heat and poison reduced lung IL- 6 expression after infection in 3 to 7 days significantly, decreased the expression of IL-1 in 5 to 7 days, also increased the lung expression of IL-10 in 1 to 5 days significantly. The method of replenishing Qi significantly reduced the expression of IL-6 after infection on the 1st day and in 5 to 7 days, decreased the expression of IL-1 in 3 to 7 days, also significantly increased the lung IL-10 on the 5th day after infection. CONCLUSION: The method of clearing away heat and poison and replenishing Qi could be against the lung immune inflammatory damage and repair damage. The method of relieving superficies with acrid-warm demonstrated some immunity against lung injury on the 3rd day after infection and the method of relieving superficies with acrid-cold demonstrated some immunity against lung injury on the 5th days after infection.