scholarly journals INHIBITION OF INFLUENZA VIRUS MULTIPLICATION BY N-GLYCOSIDES OF BENZIMIDAZOLES

1954 ◽  
Vol 99 (3) ◽  
pp. 227-250 ◽  
Author(s):  
Igor Tamm ◽  
Karl Folkers ◽  
Clifford H. Shunk ◽  
Frank L. Horsfall

Chloro derivatives of benzimidazole were found to be 2 to 3 times more active than corresponding methyl derivatives in causing inhibition of Lee virus multiplication in chorioallantoic membrane cultures in vitro. The most active benzimidazole derivative thus far tested is 5,6-dichloro-1-ß-D-ribofuranosylbenzimidazole (DRB); it caused 75 per cent inhibition of Lee virus multiplication in membrane cultures at a concentration of 0.38 x 10–4 M. On the other hand, 5,6-dimethyl-1-alpha;-D-ribofuranosylbenzimidazole, the moiety present in vitamin B12, failed to inhibit Lee virus multiplication at a concentration of 35 x 10–4 M. Other N-glycosides of 5,6-dichlorobenzimidazole were considerably less active than DRB. In single cycle experiments, the degree of inhibition of Lee virus multiplication by DRB in membrane cultures was not dependent on the amount of virus in the inoculum. This compound did not inactivate the infectivity of extracellular Lee virus, had no effect on virus-erythrocyte interaction, did not interfere with the adsorption of the virus by the host tissue, nor affect the release of newly formed virus from the membrane. The inhibitory effect of DRB on Lee virus multiplication, in contrast to that of 2,5-dimethylbenzimidazole, persisted after transfer of infected membranes into fresh culture medium not containing the compound. Both DRB and the 2,5-dimethyl compound caused 99 per cent inhibition of Lee virus multiplication without affecting oxygen uptake of the membrane. Tissue proliferation of membrane pieces in roller tube culture was not significantly affected by DRB at inhibitory concentration, whereas at equivalent concentration the 2,5-dimethyl compound did restrict cellular growth. At higher concentrations, both compounds caused retardation of cell proliferation. This effect was reversible on removal of either compound from the medium. The multiplication of several strains of influenza A and B viruses, i.e. Lee, MB, PR8, and FM1, was inhibited to the same degree by each of the two compounds; DRB was 35 times more active than the 2,5-dimethyl compound relative to each of the strains. DRB caused inhibition of Lee virus multiplication in intact embryonated chicken eggs and in mice without causing significant signs of toxicity in either host. Some of the implications of these findings are discussed in relation to the mechanism of the inhibition of influenza virus multiplication.

1954 ◽  
Vol 100 (6) ◽  
pp. 541-562 ◽  
Author(s):  
Igor Tamm ◽  
David A. J. Tyrrell

A procedure is described for kinetic studies on the multiplication of Lee virus in the chorioallantoic membrane in vitro employing the hemagglutination technique for measurement of virus concentration. A linear relationship was found between the logarithm of virus adsorbed and the amount of membrane used. Of the virus adsorbed less than 10 per cent could be recovered from the membrane. Of the recoverable virus 90 per cent was eliminated by specific immune serum. Lee virus was adsorbed by the allantoic and chorionic layers of the membrane to a similar degree. Multiplication occurred in both layers and to a similar extent. When 107.66 EID50 of Lee virus was inoculated per 2.9 cm.2 of chorioallantoic membrane, the ratio of infectivity to hemagglutination titer in the yield was low, although the rate of appearance of virus particles was not diminished despite the large inocula. Virus produced in membranes was liberated rapidly and continually into the medium. 5,6-Dichloro-1-ß-D-ribofuranosylbenzimidazole (DRB), 0.000055 M, prolonged the latent period by more than 100 per cent. The rate of increase during the period of rapid rise was similar in the presence or absence of DRB, but the yield was markedly reduced at the end of this period in the presence of DRB. The amount of the virus in the membranes continued to rise in the presence of DRB and eventually approached the maximal levels reached much earlier in the controls. Measurement of the amount of virus in the media indicated a greater degree of inhibition than did measurement in the membranes. Comparative studies with two benzimidazole derivatives on the dependence of the inhibitory effect on the time of addition of the compound showed that processes which could be inhibited by DRB were of shorter duration than those inhibited by 2,5-dimethylbenzimidazole (MB). With MB the relationship between the time of addition and the inhibitory effect was similar both for virus and for soluble complement-fixing antigen; with DRB the inhibitable processes were of shorter duration for the complement-fixing antigen than for virus particles. DRB was not only 35 times more active on a molar basis but also was more selective in its action than MB. DRB interfered with processes which preceded the emergence of either soluble complement-fixing antigen or virus particles. Some of the implications of these findings are discussed in relation to the mechanism of inhibition of influenza virus multiplication by benzimidazole derivatives.


1960 ◽  
Vol 111 (3) ◽  
pp. 339-349 ◽  
Author(s):  
Igor Tamm ◽  
Marjorie M. Nemes ◽  
Suydam Osterhout

Adenosine, but not guanosine, was capable of blocking the inhibitory effect of 5,6-dichloro-1-ß-D-ribofuranosylbenzimidazole (DRB) on influenza virus multiplication in the chorioallantoic membrane in vitro. At virus inhibitory concentrations DRB caused marked inhibition in uptake of adenosine-8-C14 into RNA of uninfected host cells, but it had little effect on uptake of C14-L-alanine into host cell proteins or on cellular oxygen consumption. The activity of DRB in inhibiting multiplication of the DNA-containing adenovirus was similar to its inhibitory activity on multiplication of the RNA-containing influenza virus. These and earlier results are discussed from the point of view of the important role of RNA in the reproduction of DNA-containing viruses.


Biomedicines ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 1721
Author(s):  
Marta De Angelis ◽  
David Della-Morte ◽  
Gabriele Buttinelli ◽  
Angela Di Martino ◽  
Francesca Pacifici ◽  
...  

Polyphenols have been widely studied for their antiviral effect against respiratory virus infections. Among these, resveratrol (RV) has been demonstrated to inhibit influenza virus replication and more recently, it has been tested together with pterostilbene against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In the present work, we evaluated the antiviral activity of polydatin, an RV precursor, and a mixture of polyphenols and other micronutrients, named A5+, against influenza virus and SARS-CoV-2 infections. To this end, we infected Vero E6 cells and analyzed the replication of both respiratory viruses in terms of viral proteins synthesis and viral titration. We demonstrated that A5+ showed a higher efficacy in inhibiting both influenza virus and SARS-CoV-2 infections compared to polydatin treatment alone. Indeed, post infection treatment significantly decreased viral proteins expression and viral release, probably by interfering with any step of virus replicative cycle. Intriguingly, A5+ treatment strongly reduced IL-6 cytokine production in influenza virus-infected cells, suggesting its potential anti-inflammatory properties during the infection. Overall, these results demonstrate the synergic and innovative antiviral efficacy of A5+ mixture, although further studies are needed to clarify the mechanisms underlying its inhibitory effect.


2022 ◽  
Author(s):  
Zheng Zhihui ◽  
Yuqian Zhang ◽  
Gang Tian ◽  
Zehua Wang ◽  
Ronghua Wang ◽  
...  

Abstract Background Pudilan Xiaoyan Oral Liquid (PDL) as a famous Chinese patent medicine has been widely used for treating upper respiratory tract infection. However, the antiviral effect of PDL remain unclear. Here, the antiviral effect of in vitro and in vivo of PDL against influenza A virus were for the first time investigated. Methods The in vitro inhibitory effect of PDL on influenza A virus was investigated using MDCK cell model. The in vivo inhibitory effect on influenza virus pneumonia was evaluated with the ICR female mice (14-16 g) model infected by influenza A virus (A/FM/1/47, H1N1, mouse-adapted). Moreover, expression levels of inflammatory cytokines including TNF-α, IP10, IL-10, IL-1β, IL-6 and IFN-γ in lung tissue were measured by qRT-PCR. The potential mechanism of PDL against acute lung injury caused by influenza A virus was investigated by RT-PCR and Western blot. Results Our results indicated that in vitro PDL has a broad-spectrum inhibitory effect on different subtypes of influenza A viruses and in vivo PDL could dose-dependently prevent weight loss of mice, increase food intake and reduce mortality caused by influenza A H1N1 virus. Furthermore, PDL could markedly improve the acute lung injury caused by influenza A virus and significantly reduce the mRNA levels of inflammatory factors such as TNF-α, IP10, IL-10, IL-1β, IL-6, and IFN-γ. Mechanistic research indicated that the protective effect of PDL on viral pneumonia might be achieved by inhibiting TLR3/MyD88/IRAK4/TRAF3 signaling pathway. Conclusion PDL not only showed a good inhibitory effect on influenza A virus in vitro, but also exhibited a significant protective effect against lethal influenza virus infection in vivo. These findings provide evidence for the clinical treatment of influenza A virus infection with PDL.


1953 ◽  
Vol 98 (3) ◽  
pp. 219-227 ◽  
Author(s):  
Igor Tamm ◽  
Karl Folkers ◽  
Frank L. Horsfall

At a concentration of 0.0026 M, 2,5-dimethylbenzimidazole caused a number of alterations in the first cycle of multiplication of influenza B virus, Lee strain, in chorioallantoic membrane cultures in vitro. As determined by infectivity titrations in ovo on the membrane per se, the following alterations were observed: The duration of the latent period was increased by 80 per cent. The rate of increase in titer during the incremental period was somewhat decreased. The yield of virus was decreased by about 99 per cent. When the compound was added to membrane cultures at various periods before or after inoculation with the virus, the following findings were obtained: On addition before or along with the virus, the substance caused about 99 per cent inhibition of multiplication. When added during the first 2 hours after inoculation, the compound caused inhibition of a degree which was inversely proportional to the time of addition. When added 3 to 8 hours after inoculation, the substance caused about 80 per cent inhibition. When added after the end of the latent period, no definite inhibition was obtained in the first cycle of multiplication. These results are interpreted as indicating that 2,5-dimethylbenzimidazole acts by reducing the rate of biosynthetic mechanisms necessary for the reproduction of influenza virus particles.


1953 ◽  
Vol 98 (3) ◽  
pp. 229-243 ◽  
Author(s):  
Igor Tamm ◽  
Karl Folkers ◽  
Frank L. Horsfall

The activity of compounds which inhibit the multiplication of influenza virus can be measured in chorioallantoic membrane cultures in vitro by means of hemagglutination titrations on the medium. Studies on the reproducibility of virus reproduction in membrane cultures have revealed the major variables which affect the results and thus have led to the development of a precise technique. Under strictly controlled experimental conditions, the extent of reproduction of the virus in membrane cultures is predictable within narrow limits of variation. With 105.5 EID50 of influenza B virus, Lee strain, and 5.75 cm.2 of chorioallantoic membrane per ml., the ratio of infective virus particles to susceptible allantoic cells appears to be approximately 1:28. Under these conditions, the evidence indicates that two cycles of multiplication occur and nearly maximal hemagglutination titers are found with culture medium at 36 hours. The extent of the deviation in the absolute titer in different experiments was only 0.112 log unit. At a concentration of 0.0017 M, 2,5-dimethylbenzimidazole caused inhibition of the multiplication of influenza B virus, Lee strain, which persisted for at least 70 hours as measured by hemagglutination titrations on the culture medium. The degree of inhibition was closely comparable to that demonstrated by infectivity titrations on the membrane at the end of the first cycle of virus reproduction (1).


2014 ◽  
Vol 95 (5) ◽  
pp. 1033-1042 ◽  
Author(s):  
Blanca García-Barreno ◽  
Teresa Delgado ◽  
Sonia Benito ◽  
Inmaculada Casas ◽  
Francisco Pozo ◽  
...  

Murine hybridomas producing neutralizing mAbs specific to the pandemic influenza virus A/California/07/2009 haemagglutinin (HA) were isolated. These antibodies recognized at least two different but overlapping new epitopes that were conserved in the HA of most Spanish pandemic isolates. However, one of these isolates (A/Extremadura/RR6530/2010) lacked reactivity with the mAbs and carried two unique mutations in the HA head (S88Y and K136N) that were required simultaneously to eliminate reactivity with the murine antibodies. This unusual requirement directly illustrates the phenomenon of enhanced antigenic change proposed previously for the accumulation of simultaneous amino acid substitutions at antigenic sites of the influenza A virus HA during virus evolution (Shih et al., Proc Natl Acad Sci USA, 104 , 6283–6288, 2007). The changes found in the A/Extremadura/RR6530/2010 HA were not found in escape mutants selected in vitro with one of the mAbs, which contained instead nearby single amino acid changes in the HA head. Thus, either single or double point mutations may similarly alter epitopes of the new antigenic site identified in this work in the 2009 H1N1 pandemic virus HA. Moreover, this site is relevant for the human antibody response, as shown by competition of mAbs and human post-infection sera for virus binding. The results are discussed in the context of the HA antigenic structure and challenges posed for identification of sequence changes with possible antigenic impact during virus surveillance.


1997 ◽  
Vol 34 (2) ◽  
pp. A88 ◽  
Author(s):  
K. Konno ◽  
H. Inoue ◽  
M. Fujiwara ◽  
T. Mizuta ◽  
H. Takayama ◽  
...  

2010 ◽  
Vol 2010 ◽  
pp. 1-5 ◽  
Author(s):  
Laura V. Ashton ◽  
Robert L. Callan ◽  
Sangeeta Rao ◽  
Gabriele A. Landolt

Infection of dogs with canine influenza virus (CIV) is considered widespread throughout the United States following the first isolation of CIV in 2004. While vaccination against influenza A infection is a common and important practice for disease control, antiviral therapy can serve as a valuable adjunct in controlling the impact of the disease. In this study, we examined the antiviral activity of nitazoxanide (NTZ) and tizoxanide (TIZ) against three CIV isolatesin vitro. NTZ and TIZ inhibited virus replication of all CIVs with 50% and 90% inhibitory concentrations ranging from 0.17 to 0.21 μMand from 0.60 to 0.76 μM, respectively. These results suggest that NTZ and TIZ are effective against CIV and may be useful for treatment of canine influenza in dogs but further investigation of thein vivoefficacy against CIV as well as the drug's potential for toxicity in dogs is needed.


Viruses ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 203
Author(s):  
Hien Thi Tuong ◽  
Ngoc Minh Nguyen ◽  
Haan Woo Sung ◽  
Hyun Park ◽  
Seon-Ju Yeo

In July 2018, a novel avian influenza virus (A/Mandarin duck/South Korea/KNU18-12/2018(H11N9)) was isolated from Mandarin ducks in South Korea. Phylogenetic and molecular analyses were conducted to characterize the genetic origins of the H11N9 strain. Phylogenetic analysis indicated that eight gene segments of strain H11N9 belonged to the Eurasian lineages. Analysis of nucleotide sequence similarity of both the hemagglutinin (HA) and neuraminidase (NA) genes revealed the highest homology with A/duck/Kagoshima/KU57/2014 (H11N9), showing 97.70% and 98.00% nucleotide identities, respectively. Additionally, internal genes showed homology higher than 98% compared to those of other isolates derived from duck and wild birds. Both the polymerase acidic (PA) and polymerase basic 1 (PB1) genes were close to the H5N3 strain isolated in China; whereas, other internal genes were closely related to that of avian influenza virus in Japan. A single basic amino acid at the HA cleavage site (PAIASR↓GLF), the lack of a five-amino acid deletion (residue 69–73) in the stalk region of the NA gene, and E627 in the polymerase basic 2 (PB2) gene indicated that the A/Mandarin duck/South Korea/KNU18-12/2018(H11N9) isolate was a typical low-pathogenicity avian influenza. In vitro viral replication of H11N9 showed a lower titer than H1N1 and higher than H9N2. In mice, H11N9 showed lower adaptation than H1N1. The novel A/Mandarin duck/South Korea/KNU18-12/2018(H11N9) isolate may have resulted from an unknown reassortment through the import of multiple wild birds in Japan and Korea in approximately 2016–2017, evolving to produce a different H11N9 compared to the previous H11N9 in Korea (2016). Further reassortment events of this virus occurred in PB1 and PA in China-derived strains. These results indicate that Japanese- and Chinese-derived avian influenza contributes to the genetic diversity of A/Mandarin duck/South Korea/KNU18-12/2018(H11N9) in Korea.


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