Article

Effects of a nutrient mixture on infectious properties of the highly pathogenic strain of avian influenza virus A/H5N1

Authors:
  • Ivanovsky Institute of Virology
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Abstract

Numerous outbreaks of avian influenza virus infection (A/H5N1) have occurred recently, infecting domestic birds, chicken and ducks. The possibility of the emergence of a new strain of influenza virus capable of causing a pandemic in humans is high and no vaccine effective against such a strain currently exists. A unique nutrient mixture (NM), containing lysine, proline, ascorbic acid, green tea extract, N-acetyl cysteine, selenium among other micro nutrients, has been shown to exert a wide range of biochemical and pharmacological effects, including an inhibitory effect on replication of influenza virus and HIV. This prompted us to investigate the potential anti-viral activity of a nutrient mixture (NM) and its components on avian influenza virus A/H5N1at viral dosages of 1.0, 0.1 and 0.01 TCID(50). Antiviral activity was studied in cultured cell lines PK, BHK-21, and Vero-E6. Virus lysing activity was determined by co-incubation of virus A/H5N1 with NM for 0-60 min, followed residual virulence titration in cultured SPEV or BHK-21 cells. NM demonstrated high antiviral activity evident even at prolonged periods after infection. NM antiviral properties were comparable to those of conventional drugs (amantadine and oseltamivir); however, NM had the advantage of affecting viral replication at the late stages of the infection process.

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... Well-known effects of green tea on human health include anti-diabetic, hypocholesterolemic, antiinflammatory and anticarcinogenic activities, as well as antiviral properties. [1][2][3][4][5][6][7] In respect of its antiviral properties, a green tea extract has been shown to have inhibitory effects on the human immunodeficiency virus, influenza virus, Epstein-Barr virus, herpes virus, and human T-cell lymphotropic virus type 1, and many other viruses. This broad-spectrum antiviral activity is expected to be found among enveloped viruses in general. ...
... 11,12) The search for antiviral substances with high efficacy, low toxicity, and minor side effects must therefore be continued from both natural and synthetic resources. [3][4][5][6][7][13][14][15] In parallel with prevention and therapy using vaccines and antivirals, much simpler and probably lower-cost intervention would be possible for reducing the transmission of epidemic respiratory viruses among the public. Enhanced hygiene, including wearing face masks and keeping the hands clean continue to be proposed as the first-hand measures against the spread of respiratory viral infection, because influenza viruses are transmitted through both skin contact and through aerosol transfer. ...
Article
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Based on the broad-spectrum antiviral effect of green tea catechins, we established an experimental skin contact model for influenza virus transmission and evaluated the use of a green tea solution as a first-hand disinfectant. The infectivity of the virus on the skin cell layer became obsolete when washed with the green tea solution. The skin contact model could be applied to develop non-pharmaceutical intervention measures for reducing human transmission of the influenza virus.
... Recently, beneficial effects of green tea or green tea catechins have also been demonstrated in avian species, for instance epigallocatechin gallate supplementation has improved antioxidant status in heat-stressed quails Tuzcu et al. (2008). Moreover, positive effects of green tea has been shown in poultry diseases such as avian influenza Song et al. (2007), Deryabin et al. (2008 and coccidiosis Jang et al. (2007). Although Jang et al. (2007 observed that dietary supplementation with 0.5% and 2% green tea powder for 2 weeks, does not significantly affect body weight gain in broiler chickens; however possible effect of higher doses or longer period of administration on performance parameters has not been clarified yet. ...
... Jang et al., 2007 observed that dietary supplementation with 0.5% and 2% green tea powder has positive effects on coccidiosis in chickens. Moreover, green tea or green tea derivatives have shown favorable effects on avian influenza viruses in vitro Deryabin et al. (2008) and Song et al. (2007). However, it should always be recognized that dietary components can affect performance parameters of the chickens by different mechanisms among them is alteration of the histological parameters of the small intestine, which subsequently can affect nutrient absorption. ...
Data
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Mosleh N, Shomali T, Hamedi S., The effects of green tea powder on performance parameters, D-xylose absorption and jejunum (histology) in broilers, Online J Vet Res., 15 (2): 147-154, 2011. Effects of green tea powder on performance parameters, D-xylose absorption and jejunal histological parameters of thirty 21-day old broiler chickens of both sexes were investigated. Birds in untreated controls gained significantly higher body weight than birds treated with green tea powder. No significant differences were observed in plasma D-xylose concentrations in any groups. Green tea consumption did not affect jejunum villus width, height/crypt depth ratio or epithelial cell area. However, villus height, area and crypt depth increased in treated birds. In conclusion, 1% green tea in diet appears to be able to lower body weight and increase FCR in broiler chickens at no apparent detriment to jejunal mucosa.
... GT and GT extracts have received much attention because of their diverse beneficial effects such as antimutagenic ( Krul et al. 2001), antioxidant ( Henning et al. 2004), anticancer (Sommer et al. 2010), antiosteoporotic (Shen et al. 2009), and above all, antihyperlipidemic ( Muramatsu et al. 1986;Suzuki et al. 1998;Yang and Koo 1997;Chan et al. 1999;Yang et al. 2001;Bose et al. 2008) properties as well as antibacterial, antitoxin, antiviral, and antifungal effects (Friedman 2007) in vivo or in vitro. Positive effects of GT have also been demonstrated in poultry diseases including avian influenza ( Deryabin et al. 2008;Song et al. 2007) and coccidiosis ( Jang et al. 2007). However, some reports show that GT may adversely affect nutrient absorption from the gastrointestinal tract of laboratory animals and humans (Frejnagel and Wroblewska 2010 ;Samman et al. 2001). ...
... Recently, positive effects of GT on poultry diseases have been evaluated. It has been demonstrated that a nutrient mixture containing GT has antiviral activity against a highly pathogenic strain of avian influenza virus (H5N1) in cultured cell lines, which is comparable to those of conventional drugs such as amantadine and oseltamivir (Deryabin et al. 2008). Moreover, semi-synthetic catechin derivatives have been shown to inhibit H2N2 and H9N2 avian influenza viruses in vitro and in ovo ( Song et al. 2007). ...
Data
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The aim of the present study was to investigate the putative effects of dietary supplementation with green tea powder on growth performance, D-xylose absorption as well as serum-selected parameters of broiler chickens. Forty 21-day-old chickens were randomly allocated into four groups and fed with diets supplemented with 0% (control), 1%, 2%, or 4% green tea powder for 2 weeks. At the end of the experiment, D-xylose absorption test was performed on all birds on a 45-min basis for 135 min, and PCV as well as serum total protein, total cholesterol, LDL-c, HDL-c, triglycerides, iron, calcium, and phosphorus concentrations were assayed. Body weight, feed intake, and feed conver-sion ratio (FCR) were also recorded during the experiment. No significant differences were observed in plasma D-xylose concentrations, PCV, or serum parameters among different groups (p>0.05). Differences in body weight, feed intake, and FCR were insignificant as well. In conclusion, dietary supplementation with green tea powder for 2 weeks has no adverse effect on PCV, intestinal absorption of D-xylose, serum total protein, lipid profile, and mineral concentrations as well as performance parameters of broiler chickens.
... Positive effects of green tea have been demonstrated in poultry diseases including coccidiosis (Jang et al. 2007) and avian influenza (Deryabin et al. 2008;Song et al. 2007). Seven species of Eimeria (an intracellular protozoan) belonging to the phylum Apicomplexa cause avian coccidiosis, which is an economically important disease in the poultry industry. ...
... The structureactivity data of catechin derivatives may usefully guide future research endeavours for applying green tea catechins as alternative anti-viral agents. Subsequently Deryabin et al. (2008) investigated the potential anti-viral activity of a unique nutrient mixture (NM) (containing green tea extract, lysine, proline, ascorbic acid, N-acetyl cysteine and selenium, amongst other micronutrients) and its components on A/H5N1 at viral dosages of 1.0, 0.1 and 0.01 TCID 50 . Antiviral activity was studied in cultured cell lines PK, BHK-21, and Vero-E6. ...
Article
Full-text available
This review examined the use of green tea (Camellia sinensis) in the diets of poultry. Research findings were obtained from various recent studies, where much attention was focused on the role of green tea in the promotion of both animal and human health. The review involved some of the currently available information about green tea, pertaining to its chemical composition, anticoccidial and antimicrobial effect, effect on broiler and layer performance and on blood and egg yolk constituents. To the author's knowledge this is the first review paper on this topic. It will be helpful for poultry nutritionists and the poultry industry, although more detailed studies are still needed to elucidate the effects of green tea in poultry nutrition under various circumstances.
... Positive influence of Camellia sinensis was also observed against poultry infections including coccidiosis and influenza ( Jang et al., 2007). The leaves as well as by-products of Camellia sinensis can be provided to the broilers as a feed supplement in order to reduce mortality and improve performance (Deryabin et al., 2008;Uuganbayar et al., 2005). Yang et al. (2003) demonstrated that feeding of different levels of Camellia sinensis to animals declines the level of fatty acids and cholesterol in muscles and plasma and also improve the meat quality. ...
... The activity of epigallocatechin gallate against adenovirus is demonstrated in different levels like direct inactivation of virus, protease adenine inhibition or intracellular growth inhibition. Epigallocatechin gallate is most potent antiviral molecule because of its structure having paragalloyl and galloyl moieties (Deryabin et al. 2008;Ishii et al. 2010). These groups are responsible factor for antiviral activity. ...
... The activity of epigallocatechin gallate against adenovirus is demonstrated in different levels like direct inactivation of virus, protease adenine inhibition or intracellular growth inhibition. Epigallocatechin gallate is most potent antiviral molecule because of its structure having paragalloyl and galloyl moieties (Deryabin et al. 2008;Ishii et al. 2010). These groups are responsible factor for antiviral activity. ...
Chapter
The food industry is generating huge amounts of by-products, about 1,890,000 tons, which should be better recycled into pharmaceuticals, cosmetics and functional foods, for instance, in order to save costs and avoid pollution. Here we review food by-products and methods of extraction. We present bioactive compounds from fruits, vegetable, tea, coffee, egg, nuts, meat and dairy products. Extracting methods include soxhlet, maceration, microwave, ultrasound, pressure.
... Fatty acid monoester derivatives of EGCG, especially those with long alkyl chains, exhibited a sharply increased antiviral effect against IAV compared to natural EGCG [57]. The inhibitory effects of different nutrient mixtures of natural EGCG on influenza virus have also been demonstrated by different investigators [58,81,82]. Some researchers contributed to clinical trials of EGCG as an IAV restriction factor [59]. ...
... The application of lyophilized green tea extracts (GTE) in feed or drinking water reduced the replication and excretion in H9N2 experimentally infected chickens (Lee et al., 2012). Moreover, GTE was effective as amantadine in protection of chicken embryos against an H7N3 AIV (Shaukat et al., 2011) or cell culture after infection with H5N1 virus (Deryabin et al., 2008). Interestingly, GTE was found to enhance the immune response of mice to influenza vaccines (Won et al., 2017;Zaman et al., 2019). ...
Preprint
Highly pathogenic avian influenza virus (HPAIV) H5N1 is an endemic disease in Egypt and severe outbreaks have been reported even in vaccinated flocks. Several H5 vaccines have failed to protect birds against Egyptian H5N1 virus. In this study, the antiviral effect of green tea extract (GTE) in combination with inactivated H5N1 vaccine was evaluated. GTE found to be safe at high concentration on Vero cells and decrease the CPE on infected cells. In vivo, specific pathogen free chickens were allocated into four groups, 15 birds each. Negative control group, positive control group, vaccinated group, vaccinated group supplied by GTE in drinking water (5gm/L). Blood samples were collected weekly and tested using (HI) test. Lung tissue specimens collected for histopathology and immunohistochemistry. Interestingly, vaccinated non-treated birds exhibited severe post vaccinal reaction and deaths. GTE in combination with inactivated vaccine increased HI titer one-week post vaccination, and no deaths were recorded in this group. Moreover, treated chickens did not excrete virus in swab samples and minimal antigen and pathological changes were reported in its lungs. The addition of GTE prevent the shedding of the virus and achieve complete protection against HPAI.
... This processing produces glucuronide and sulfate conjugates or methyl epicatechins [4]. Lim et al. demonstrated that green tea flavonoids have anti-inflammatory and anti-enzymatic activities by reducing NLRP3 ral effects on influenza virus subtypes by inhibiting its replication, RNA synthesis and agglutination in cell culture [12]. ...
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... Fatty acid monoester derivatives of EGCG, especially those with long alkyl chains, exhibited a sharply increased antiviral effect against IAV compared to natural EGCG [57]. The inhibitory effects of different nutrient mixtures of natural EGCG on influenza virus have also been demonstrated by different investigators [58,81,82]. Some researchers contributed to clinical trials of EGCG as an IAV restriction factor [59]. ...
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Over the centuries, infectious diseases caused by viruses have seriously threatened human health globally. Viruses are responsible not only for acute infections but also many chronic infectious diseases. To prevent diseases caused by viruses, the discovery of effective antiviral drugs, in addition to vaccine development, is important. Green tea catechins (GTCs) are polyphenolic compounds from the leaves of Camellia sinensis. In recent decades, GTCs have been reported to provide various health benefits against numerous diseases. Studies have shown that GTCs, especially epigallocatechin-3-gallate (EGCG), have antiviral effects against diverse viruses. The aim of this review is to summarize the developments regarding the antiviral activities of GTCs, to discuss the mechanisms underlying these effects and to offer suggestions for future research directions and perspectives on the antiviral effects of EGCG.
... Based on this study and our earlier findings [18,19,27], this combination of plant-derived compounds and micronutrients may constitute a new anti-SARS-CoV-2 strategy by simultaneously affecting multiple aspects of viral life cycle, including viral entry and replication. This strategy was also implemented in our earlier studies, including those of human influenza H1N1, bird flu H1N5, and others, which were based on selecting natural components that simultaneously affect key pathology mechanisms across a wide spectrum of infective agents [28][29][30][31]. ...
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This review examined the use of green tea (Camellia sinensis) in the diets of poultry. Research findings were obtained from various recent studies, where much attention was focused on the role of green tea in the promotion of both animal and human health. The review involved some of the currently available information about green tea, pertaining to its chemical composition, anticoccidial and antimicrobial effect, effect on broiler and layer performance and on blood and egg yolk constituents. To the author's knowledge this is the first review paper on this topic. It will be helpful for poultry nutritionists and the poultry industry, although more detailed studies are still needed to elucidate the effects of green tea in poultry nutrition under various circumstances.
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The reproduction of highly pathogenic avian influenza (HPAI) A/tern/SA/61 H5N3 and A/ducklNovosibirsk/56/05 H5NI viruses was comparatively studied in 16 human and animal cell lines. The strain A/duck/Novosibirsk/56/05 was shown to have a wider range of hosts. The most sensitive transplanted cell lines were found to be feline fibroblasts (CC-81), primarily trypsin-treated cells of chick embryonic fibroblasts (CEF), the kidney of dogs (MDCK), pigs (SPEV), monkeys (Vero), the human conjunctiva (1-5C-4), and, to a lesser extent, the feline kidney (CRFK). Unlike the strain A/tern/South Africa/61, that A/duck/Novosibirsk/56105 replicated in the polecat brain cells (Mpf).
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The proteolytic degradation of the extracellular matrix by the protease plasmin is a universal mechanism determining human health and disease. Under physiological conditions plasmin- induced proteolysis is involved in cell migration as well as organ remodeling. Under pathological conditions this mechanism is exacerbated leading to a sustained degradation of the extracellular matrix. Plasmin-induced proteolysis is an important pathomechanism, not only for the proliferation of cancer and viral processes but also for cardiovascular disease and most other diseases. The exacerbation of this mechanism is characterized by a chronic imbalance between activators and inhibitors of this proteolytic pathway. Optimum availability of endogenous and exogenous inhibitors of plasmin-induced proteolysis is an important physiologic and therapeutic aim. We recently proposed that apoprotein(a), apo(a), functions as an endogenous inhibitor of plasmin-induced proteolysis. We now propose that this function of apo(a) is also an important determinant for the evolutionary advantage of this molecule. This function of apo(a) can explain the unique structure of the apo(a) molecule and the selective advantage of the plasminogen kringle IV as compared to the other plasminogen kringles. We also proposed that the effectiveness of apo(a) as an inhibitor of plasmin-induced proteolysis depends on an optimum number of kringle repeats. This could explain not only the inverse relation of kringle repeats to the synthesis rate of apo(a) molecules but also the remarkably high genetic variation of individual plasma levels of lipoprotein (a), Lp(a). Exogenous inhibitors of plasmin-induced proteolysis include the essential amino acid L- lysine and synthetic lysine analogs such as tranexamic acid. Di-
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Influenza, one of the oldest and most common infections, poses a serious health problem causing significant morbidity and mortality, and imposing substantial economic costs. The efficacy of current drugs is limited and improved therapies are needed. A unique nutrient mixture (NM), containing ascorbic acid, green tea extract, lysine, proline, N-acetyl cysteine, selenium among other micronutrients, has been shown to exert anti-carcinogenic and anti-atherogenic activity both in vitro and in vivo. Many of the constituents of NM have been shown to have an inhibitory effect on replication of influenza virus and HIV. This prompted us to study the effect of NM on influenza A virus multiplication in infected cells and neuraminidase activity (NA) in virus particles. Addition of NM to Vero or MDCK cells post infection resulted in dose-dependent inhibition of viral nucleoprotein (NP) production in infected cells. NM-mediated inhibition of viral NP was selective and not due to cytotoxicity towards host cells. This antiviral effect was enhanced by pretreatment of virus with the nutrient mixture. Individual components of NM, namely ascorbic acid and green tea extract, also blocked viral NP production, conferring enhanced inhibition when tested in combination. Incubation of cell-free virus with NM resulted in dose-dependent inhibition of associated NA enzyme activity. In conclusion, the nutrient mixture exerts an antiviral effect against influenza A virus by lowering viral protein production in infected cells and diminishing viral enzymatic activity in cell-free particles.
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We have studied the action of ascorbate (vitamin C) on human immunodeficiency virus type 1 (HIV-1), the etiological agent clinically associated with AIDS. We report the suppression of virus production and cell fusion in HIV-infected T-lymphocytic cell lines grown in the presence of nontoxic concentrations of ascorbate. In chronically infected cells expressing HIV at peak levels, ascorbate reduced the levels of extracellular reverse transcriptase (RT) activity (by greater than 99%) and of p24 antigen (by 90%) in the culture supernatant. Under similar conditions, no detectable inhibitory effects on cell viability, host metabolic activity, and protein synthesis were observed. In freshly infected CD4+ cells, ascorbate inhibited the formation of giant-cell syncytia (by approximately 93%). Exposure of cell-free virus to ascorbate at 37 degrees C for 1 day had no effect on its RT activity or syncytium-forming ability. Prolonged exposure of virus (37 degrees C for 4 days) in the presence of ascorbate (100-150 micrograms/ml) resulted in the drop by a factor of 3-14 in RT activity as compared to a reduction by a factor of 25-172 in extracellular RT released from chronically infected cells. These results indicate that ascorbate mediates an anti-HIV effect by diminishing viral protein production in infected cells and RT stability in extracellular virions.
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Among the molecular maneuvers that enable the influenza virus to survive are antigenic variation and functional alterations. Two kinds of minor antigenic variations, producing new strains within type A virus subtypes, have been discovered: antigenic drift, in which the amino acid sequences of the antigens are changed; and antigenic camouflage, in which the antigens are glycosylated. Both kinds of variation are caused by mutations in the viral genome. These mutations produce slightly changed antigens, which many existing antibodies cannot recognize. Major antigenic variations (so-called antigenic shift) are produced by gene reassortment. Two subtypes, coinfecting a host, can reassort their eight ribonucleoprotein gene segments into as many as 256 different combinations. Such recombinations can produce new viruses with the potential for transmission in humans, but whose surface antigens are completely unmatched by antibodies in the population, permitting a pandemic to occur. Functional changes, caused by mutations, alter the interactions between the virus and the host, including virus binding to host receptor sites and fusion of viral and host membranes. All these mechanisms allow the influenza virus to survive in humans, probably perpetually.
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Four hundred fifty volunteers participated in a placebo-controlled, double-blind, randomized trial of the prophylactic effects of rimantadine and amantadine during an outbreak of influenza A. The subjects received drugs orally at a dose of 100 mg twice a day for six weeks. Influenza-like illness occurred in 41 per cent of the subjects receiving placebo but in only 14 per cent of those receiving rimantadine and 9 per cent of these receiving amantadine (P less than 0.001 for either drug vs. placebo). Laboratory-documented influenza occurred in 21 per cent of placebo recipients, 3 per cent of rimantadine recipients, and 2 per cent of amantadine recipients (P less than 0.001). These findings represent efficacy rates of 85 per cent for rimantadine and 91 per cent for amantadine, as compared with placebo. More recipients of amantadine (13 per cent) than recipients of rimantadine (6 per cent; P less than 0.05) or placebo (4 per cent; P less than 0.01) withdrew from the study because of central-nervous-system side effects. On the basis of this study, rimantadine appears to be the drug of choice for the prophylaxis of influenza A.
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(-)Epigallocatechin gallate (EGCg) and theaflavin digallate (TF3) (1-10 microM) inhibited the infectivity of both influenza A virus and influenza B virus in Madin-Darby canine kidney (MDCK) cells in vitro. Study by electron microscope revealed that EGCg and TF3 (1 mM) agglutinated influenza viruses as well as did antibody, and that they prevented the viruses from adsorbing to MDCK cells. EGCg and TF3 more weakly inhibited adsorption of the viruses to MDCK cells. EGCg and TF3 (1-16 microM) also inhibited haemagglutination by influenza viruses. These findings suggest that tea polyphenols bind to the haemagglutinin of influenza virus, inhibit its adsorption to MDCK cells, and thus block its infectivity.
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We investigated the effect of influenza A/Beijing/353/89 (H3N2) virus infection on the expression of type IV collagenase in two different types of epithelial cell. Depending on the cell line infected, the viral infection caused changes in the expression of type IV collagenase. The expression of matrix metalloproteinase-9 (MMP-9; 92 kDa) but not of matrix metalloproteinase-2 (MMP-2; 72 kDa) was stimulated in Vero cells. In MDCK cells, the MMP-2 production increased with the virus infection. According to the enzymatic activity revealed with zymography, the MMP-9 promoter activity rose by a factor of over 1788 in influenza A virus-infected Vero cells but not in MDCK cells. The tissue inhibitor of metalloproteinase, TIMP-1, had increased slightly (2.3-fold) in Vero cells 48 hours after the infection, but in MDCK cells, influenza A virus had no effect on the TIMP-1 expression. In conclusion, the MMP-9 and -2 expression by influenza A virus infection are modulated at transcriptional level, depending on the epithelial cell line.
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Safe and effective antiviral agents are needed to prevent infection with influenza A and B virus. Oseltamivir (GS4104), which can be administered orally, is the prodrug of GS4071, a potent and selective inhibitor of influenzavirus neuraminidases. We studied the use of oseltamivir for long-term prophylaxis against influenza in two placebo-controlled, double-blind trials at different U.S. sites during the winter of 1997-1998. We randomly assigned 1559 healthy, nonimmunized adults 18 to 65 years old to receive either oral oseltamivir (75 mg given once or twice daily, for a total daily dose of 75 or 150 mg) or placebo for six weeks during a peak period of local influenzavirus activity. The primary end point with respect to efficacy was laboratory-confirmed influenza-like illness (defined as a temperature of at least 37.2 degrees C accompanied by at least one respiratory and at least one systemic symptom). In the two studies combined, the risk of influenza among subjects assigned to either once-daily or twice-daily oseltamivir (1.2 percent and 1.3 percent, respectively) was lower than that among subjects assigned to placebo (4.8 percent; P<0.001 and P=0.001 for the comparison with once-daily and twice-daily oseltamivir, respectively). The protective efficacy of oseltamivir in the two active-treatment groups combined was 74 percent (95 percent confidence interval, 53 to 88 percent) at all the sites combined and 82 percent (95 percent confidence interval, 60 to 93 percent) at sites in Virginia, where the rate of influenza infection was higher than the overall rate. For culture-proved influenza, the rate of protective efficacy in the two oseltamivir groups combined was 87 percent (95 percent confidence interval, 65 to 96 percent). The rate of laboratory-confirmed influenza infection was lower with oseltamivir than with placebo (5.3 percent vs. 10.6 percent, P<0.001). Oseltamivir was well tolerated but was associated with a greater frequency of nausea (12.1 percent and 14.6 percent in the once-daily and twice-daily groups, respectively) and vomiting (2.5 percent and 2.7 percent, respectively) than was placebo (nausea, 7.1 percent; vomiting, 0.8 percent). However, the frequency of premature discontinuation of drug or placebo was similar among the three groups (3.1 to 4.0 percent). Oseltamivir administered daily for six weeks by the oral route is safe and effective for the prevention of influenza.
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Selenium, an essential biological trace element, has been shown to reduce and prevent the incidence of cancer. Our previous studies have shown that selenite is involved in the chemoprevention of cancer and induction of apoptosis of cancer cells. In this study, we demonstrate that selenite also inhibits the invasion of tumor cells. Cancer cell invasion requires coordinated processes, such as changes in cell-cell and cell-matrix adhesion, degradation of the extracellular matrix, and cell migration. We found that selenite inhibited invasion of HT1080 human fibrosarcoma cells. Adhesion of HT1080 cells to the collagen matrix was also inhibited by treatment with selenite, but cell-cell interaction and cell motility were not affected by selenite. Moreover, selenite reduced expression of matrix metalloproteinase-2 and -9 and urokinase-type plasminogen activator, which are involved in matrix degradation, but increased a tissue inhibitor of metalloproteinase-1. This inhibitory effect of selenite on the protease expressions was mediated by the suppression of transcription factors, NF-κB and AP-1. However, selenate showed no remarkable effect on all the steps of cancer cell invasion.
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MMPs play a crucial role in the process of cancer invasion and metastasis. The influence of NAC on invasion and MMP-9 production of human bladder cancer cell line T24 was investigated using an in vitro invasion assay, gelatin zymography, Western and Northern blot analyses and RT-PCR assays. TPA increased the number of invading T24 cells through reconstituted basement membrane more than 10-fold compared to basal condition. NAC inhibited TPA-enhanced invasion dose-dependently. TPA increased the MMP-9 production by T24 cells without altering expression of TIMP-1 gene, while NAC suppressed TPA-enhanced production of MMP-9. Neither TPA nor NAC altered TIMP-1 mRNA level in T24 cells. In vitro experiments demonstrated that MMP-9 was directly inhibited by NAC but was not influenced by TPA. NAC limits invasion of T24 human bladder cancer cells by inhibiting the MMP-9 production in addition to a direct inhibition of MMP-9 activity.
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Epigallocatechin-3-gallate (EGCG), one of the components of green tea, has been suggested to have antiviral activity. To determine the effects of EGCG on HIV infection, peripheral blood lymphocytes were incubated with either LAI/IIIB or Bal HIV strains and increasing concentrations of EGCG. EGCG strongly inhibited the replication of both virus strains as determined by reverse transcriptase and p24 assays on the cell supernatants.
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It has been previously reported that green-tea extract (GTE) inhibits the growth of influenza virus by preventing its adsorption. In this study, we further investigated whether GTE exerts an additional inhibitory effect on the acidification of intracellular compartments such as endosomes and lysosomes (referred to as ELS) and thereby inhibits the growth of influenza A and B viruses in Madin-Darby canine kidney cells. The vital fluorescence microscopic study showed that GTE inhibited acidification of ELS in a concentration-dependent manner. Moreover, the growth of influenza A and B viruses was equally inhibited when the cells were treated with GTE within as early as 5 to 15 min after infection, depending on the virus strains. The fact that (-)epigallocatechin (EGC), one of major catechin molecules in GTE, exerts the inhibitory effects on the acidification of ELS and virus growth in a manner similar to that of GTE strongly suggests that EGC is one of the active components in the extract.
Article
Reactive oxygen intermediates (ROI) and cytokines, particularly tumor necrosis factor (TNF) have been implicated in the pathogenesis of influenza. Using a murine model of influenza, we have studied the levels of TNF, interleukin 6 (IL-6) and of superoxide-generating xanthine oxidase (XO). Mice infected intranasally with influenza virus APR/8 had high levels of XO, TNF and IL-6 in the broncoalveolar lavage, as early as 3 d after infection. XO was elevated also in serum and lung tissue. Administration of the antioxidant N-acetylcysteine (NAC,1 g/kg per day, orally) significantly decreased the mortality in infected mice, indicating a role for RO1 in the lethality associated with influenza infection.
Article
Oxidative stress is implicated in the pathogenesis of pulmonary damage during viral infections. In a previous study we observed a significant improvement of survival of influenza-infected mice with NAC, 1g/kg divided in two daily administrations, for 8 days including a pretreatment on day 1 before infection. In order to test NAC in a more realistic model, we studied the effect of combined treatment with NAC and the antiviral drug, ribavirin. Since in the present work we wanted to test a possible synergistic effect by combination of NAC and ribavirin, we used a different NAC's treatment regimen (1 g/kg, once a day for 4 days) that, alone, did not significantly protect mice from death. Mice (12 per group) infected intranasally with a lethal dose of influenza A virus APR/8. NAC was given as a single daily dose of 1000 mg/kg starting from 4 h after infection and until day 4 after infection, in association with ribavirin (100 mg/kg, i.p.). End-point evaluation was 14-day survival. With this schedule survival in infected mice was 17%, it was not significantly changed by NAC (25%). Survival increased to 58% with ribavirin and to 92% (n=12) with a combined treatment with ribavirin and NAC. This suggest that antioxidant therapy can increase survival by either improving the defenses against virus or by protecting from the pathogenesis of lung inflammation.
Article
Outbreaks of highly pathogenic H5N1 avian influenza have occurred in Hong Kong in chickens and other gallinaceous poultry in 1997, 2001, twice in 2002 and 2003. High mortality rates were seen in gallinaceous birds but not in domestic or wild waterfowl or other wild birds until late 2002 when highly pathogenic H5N1 avian influenza occurred in waterfowl (geese, ducks and swans), captive Greater Flamingo (Phoenicopterus ruber) and other wild birds (Little Egret Egretta garzetta) at two waterfowl parks and from two dead wild Grey Heron (Ardea cinerea) and a Black-headed Gull (Larus ridibundus) in Hong Kong. H5N1 avian influenza virus was also isolated from a dead feral pigeon (Columba livia) and a dead tree sparrow (Passer montanus) during the second outbreak. The first waterfowl outbreak was controlled by immediate strict quarantine and depopulation 1 week before the second outbreak commenced. Control measures implemented for the second outbreak included strict isolation, culling, increased sanitation and vaccination. Outbreaks in gallinaceous birds occurred in some live poultry markets concurrently with the second waterfowl outbreak, and infection on a chicken farm was detected 1 week after the second waterfowl park outbreak was detected, on the same day the second grey heron case was detected. Subsequent virus surveillance showed the outbreaks had been contained.
Article
Degradation of extracellular matrix (ECM) is a hallmark of tumor invasion, metastasis and angiogenesis. Based on the Rath multitargeted approach to cancer using natural substances to control ECM stability and enhancing its strength, we developed a novel formulation (NM) of lysine, proline, ascorbic acid and green tea extract that has shown significant anti-cancer activity against a number of cancer cell lines. The aim of the present study was to determine whether NM exhibits anti-angiogenic and anti-metastatic effects using in vitro and in vivo experimental models. Angiogenesis was measured using a chorioallantoic membrane (CAM) assay in chick embryos and bFGF-induced vessel growth in C57BL/6J female mice. To determine the in vivo effect of NM on the tumor xenograft growth, male nude mice were inoculated with 3 x 10(6) MNNG-HOS cells. Control mice were fed a mouse chow diet, while the test group was fed a mouse chow diet supplemented with 0.5% NM for 4 weeks. In vitro studies on cell proliferation (MTT assay), MMP expression (zymography) and Matrigel invasion were conducted on human osteosarcoma U2OS, maintained in McCoy medium, supplemented with 10% FBS, penicillin and streptomycin in 24-well tissue culture plates and tested with NM at 0, 10, 50, 100, 500, and 1000 microg/ml in triplicate at each dose. NM at 250 microg/ml caused a significant (p<0.05) reduction in bFGF-induced angiogenesis in CAM. NM inhibited tumor growth of osteosarcoma MNNG-HOS cell xenografts in nude mice by 53%; furthermore, tumors in NM-treated mice were less vascular and expressed lower levels of VEGF and MMP-9 immunohistochemically than tumors in the control group. In addition, NM exhibited a dose-dependent inhibition of osteosarcoma U2OS cell proliferation (up to 60% at 1000 microg/ml), MMP-2 and -9 expression (with virtual total inhibition at 500 microg/ml NM), and invasion through Matrigel (with total inhibition at 100 microg/ml NM). Moreover, NM decreased U2OS cell expression of VEGF, angiopoietin-2, bFGF, PDGF and TGFbeta-1. These results together with our earlier findings suggest that NM is a relatively non-toxic formulation, which inhibits growth, invasion, metastasis, and angiogenesis of tumor cells.
Article
Michael P.Clark, Mark W.Ledeboer, IoanaDavies, Randal A.Byrn, Steven M.Jones, EmanuelePerola, AliceTsai, MarcJacobs, KwameNti-Addae, Upul K.Bandarage, Michael J.Boyd, Randy S.Bethiel, John J.Court, HongboDeng, John P.Duffy, Warren A.Dorsch, Luc J.Farmer, HuaiGao, WenxinGu, KatrinaJackson, Dylan H.Jacobs, Joseph M.Kennedy, BrianLedford, JianglinLiang, FrançoisMaltais, MarkMurcko, TianshengWang, M. WoodsWannamaker, Hamilton B.Bennett, Joshua R.Leeman, ColleenMcNeil, William P.Taylor, ChristineMemmott, MinJiang, ReneRijnbrand, ChristopherBral, UrsulaGermann, AzinNezami, YuegangZhang, Francesco G.Salituro, Youssef L.Bennani, Paul S.Charifson. (2014) Discovery of a Novel, First-in-Class, Orally Bioavailable Azaindole Inhibitor (VX-787) of Influenza PB2. Journal of Medicinal Chemistry 57, 6668-6678 CrossRef
Article
Use of antivirals is recommended for the control of seasonal and pandemic influenza. Our aim was to review the evidence of efficacy, effectiveness, and safety of registered antivirals against naturally occurring influenza in healthy adults. We searched various Databases to October, 2005, and contacted manufacturers and corresponding authors. We included randomised controlled trials comparing prophylactic (n=27) or treatment (n=27) efficacy against symptomatic or asymptomatic influenza. We did a meta-analysis and expressed prophylactic efficacy as a proportion (1-relative risk [RR]). For treatment trials, because of inconsistent and non-standardised reporting, we expressed continuous outcomes either as means or as hazard ratios. We included 51 reports of 52 randomised controlled trials. Amantadine prevented 61% (95% CI 35-76) of influenza A cases and 25% (13-36) of cases of influenza-like illness, but caused nausea (OR 2.56, 1.37-4.79), insomnia and hallucinations (2.54, 1.50-4.31), and withdrawals because of adverse events (2.54, 1.60-4.06). There was no effect on asymptomatic cases (RR 0.85, 0.40-1.80). In treatment, amantadine significantly shortened duration of fever compared with placebo (by 0.99 days, -1.26 to -0.71), but had no effect on nasal shedding of influenza A viruses (0.93, 0.71-1.21). The fewer data for rimantadine showed comparable effects. In prophylaxis, compared with placebo, neuraminidase inhibitors have no effect against influenza-like illness (1.28, 0.45-3.66 for oral oseltamivir 75 mg daily, 1.51, 0.77-2.95 for inhaled zanamivir 10 mg daily). Higher doses appear to make no difference. The efficacy of oral oseltamivir 75 mg daily against symptomatic influenza is 61% (15-82), or 73% (33-89) at 150 mg daily. Inhaled zanamivir 10 mg daily is 62% efficacious (15-83). Neither neuraminidase inhibitor appeared effective against asymptomatic influenza. Oseltamivir induces nausea (OR 1.79, 1.10-2.93), especially at higher prophylactic doses (2.29, 1.34-3.92). Oseltamivir in a post-exposure prophylaxis role has a protective efficacy of 58.5% (15.6-79.6) for households and from 68% (34.9-84.2) to 89% (67-97) in contacts of index cases. In influenza cases, compared with placebo the hazard ratios for time to alleviation of symptoms were 1.33, 1.29-1.37 for zanamivir; 1.30, 1.13-1.50 for oseltamivir provided medication was started within 48 h of symptom onset. Viral nasal titres were significantly diminished by both drugs (weighted mean difference -0.62, -0.82 to -0.41). Oseltamivir at 150 mg daily was effective in preventing lower respiratory tract complications in influenza cases (OR 0.32, 0.18-0.57). We could find no credible data on the effects of oseltamivir on avian influenza. The use of amantadine and rimantadine should be discouraged. Because of their low effectiveness, neuraminidase inhibitors should not be used in seasonal influenza control and should only be used in a serious epidemic or pandemic alongside other public-health measures.
Article
Certain drastic behavioral modifications by arterial wall smooth muscle cells (SMC) have been considered key steps in the formation of atherosclerotic lesions: massive migration of SMC from the media to the intima layer of the vessel, dedifferentiation of SMC to proliferating phenotype, and increased secretion of inflammatory cytokines as a response to inflammatory stimuli. We investigated the anti-atherogenic effects of naturally occurring compounds (ascorbic acid, green tea extract, lysine, proline, arginine, and N-acetyl cysteine) using the model of cultured aortic SMC. Cell growth was measured by DNA synthesis, cell invasiveness was measured through Matrigel, matrix metalloproteinase-2 (MMP-2) secretion was measured by zymography, and SMC secretion of monocyte chemoattractant protein-1 (MCP-1) and interleukin-6 (IL-6) was measured by immunochemistry. Fetal bovine serum-stimulated SMC growth was inhibited by the nutrient mixture (NM) with 85% inhibition at 100 microg/mL. A corresponding concentration of epigallocatechin gallate (EGCG; 15 microM), the most active tea phenolic, produced a significant effect but one lower than NM. NM inhibited aortic SMC Matrigel invasion in a dose-dependent manner and significantly decreased MMP-2 expression. Stimulation of SMC with tumor necrosis factor-alpha significantly increased production and secretion of such mediators of inflammation as IL-6 and MCP-1; addition of 100 microg/mL NM inhibited secretion of MCP-1 and IL-6 by 65% and 47%, respectively. These data suggest that the NM of ascorbic acid, tea phenolics, and selected amino acids has potential in blocking the development of atherosclerotic lesions by inhibiting atherogenic responses of vascular SMC to pathologic stimuli and warrants in vivo studies.
Evaluation of the efficacy of Epican Forte against avian flu virus
  • E K Barbour
  • E G Rayya
  • H Shaib
  • R G Hakim
  • A Niedzwiecki
  • A M A Nour
  • S Harakeh
E.K. Barbour, E.G. Rayya, H. Shaib, R.G. El Hakim, A. Niedzwiecki, A.M.A. Nour and S. Harakeh, Rath M. Evaluation of the efficacy of Epican Forte against avian flu virus, Intern J Appl Res Vet Med 5(1) (2007), 9–16.
Cu(II) inhibition of the proton translocation machinery of the influenza A virus by gentian violet (GV) and GV-dyed cotton cloth, and bacteriological activities of these agents
  • C S Ghandi
  • K Shuck
  • J D Lear
  • G R Dieckmann
  • W F De
  • R A Grado
  • Lamb
C.S. Ghandi, K. Shuck, J.D. Lear, G.R. Dieckmann, W.F. De Grado and R.A. Lamb, Cu(II) inhibition of the proton translocation machinery of the influenza A virus by gentian violet (GV) and GV-dyed cotton cloth, and bacteriological activities of these agents, J Infect Chemother 12 (1999), 73–79.
Serum markers of the liver, heart, and kidney and lipid profile and histopathology in ODS rats treated with nutrient synergy
  • M W Roomi
  • V Ivanov
  • S P Netke
  • A Niedzwiecki
  • M Rath
M.W. Roomi, V. Ivanov, S.P. Netke, A. Niedzwiecki and M. Rath, Serum markers of the liver, heart, and kidney and lipid profile and histopathology in ODS rats treated with nutrient synergy, J Am Coll Nutr 22(5) (2003), 477, Abstract #86.
Rath M. Evaluation of the efficacy of Epican Forte against avian flu virus
  • Barbour
Serum markers of the liver, heart, and kidney and lipid profile and histopathology in ODS rats treated with nutrient synergy
  • Roomi
Cu(II) inhibition of the proton translocation machinery of the influenza A virus by gentian violet (GV) and GV-dyed cotton cloth, and bacteriological activities of these agents
  • Ghandi