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This is
a Partial Collection of Studies, There are Many More.
Clin Diagn Lab Immunol. 1997 July; 4 (4):
465–468 Christopher B. Buck1, Cynthia D. Thompson1, Jeffrey N. Roberts1, Martin Muller2, Douglas R. Lowy1, John T. Schiller1* 1 Laboratory of Cellular Oncology, National Cancer Institute, Bethesda, Maryland, United States of America, 2 Forschungsschwerpunkt fur Angewandte Tumorvirologie, Deutsches Krebsforschungszentrum, Heidelberg, Germany Certain sexually transmitted human papillomavirus (HPV) types are causally associated with the development of cervical cancer. Our recent development of high-titer HPV pseudoviruses has made it possible to perform high- throughput in vitro screens to identify HPV infection inhibitors. Comparison of a variety of compounds revealed that carrageenan, a type of sulfated polysaccharide extracted from red algae, is an extremely potent infection inhibitor for a broad range of sexually transmitted HPVs. Although carrageenan can inhibit herpes simplex viruses and some strains of HIV in vitro, genital HPVs are about a thousand-fold more susceptible, with 50% inhibitory doses in the low ng/ml range. Carrageenan acts primarily by preventing the binding of HPV virions to cells. This finding is consistent with the fact that carrageenan resembles heparan sulfate, an HPV cell-attachment factor. However, carrageenan is three orders of magnitude more potent than heparin, a form of cell-free heparan sulfate that has been regarded as a highly effective model HPV inhibitor. Carrageenan can also block HPV infection through a second, postattachment heparan sulfate–independent effect. Carrageenan is in widespread commercial use as a thickener in a variety of cosmetic and food products, ranging from sexual lubricants to infant feeding formulas. Some of these products block HPV infectivity in vitro, even when diluted a million-fold. Clinical trials are needed to determine whether carrageenan-based products are effective as topical microbicides against genital HPVs. Citation: Buck CB, Thompson CD, Roberts JN, Muller M, Lowy DR, et al. (2006) Carrageenan is a potent inhibitor of papillomavirus infection. PLoS Pathog 2(7): e69. DOI: 10. 1371/journal.ppat.0020069 Antiherpetic activity and mode of action of natural carrageenans of diverse structural types. Carlucci MJ, Ciancia M, Matulewicz MC, Cerezo AS, Damonte EB. Departamento de Quimica Biologica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Argentina. The lambda-carrageenan 1T1, the kappa/iota-carrageenan 1C1 and the mu/nu-type 1C3, isolated from the red seaweed Gigartina skottsbergii, proved to be potent and selective inhibitors of herpes simplex virus (HSV) types 1 and 2. The antiviral IC50 values determined by virus yield inhibition assay in different cell lines ranged from 0.4 to 3.3 microg/ml, and no cytotoxic effects, measured by trypan blue exclusion on stationary or proliferating cells, tetrazolium salt method or cell protein synthesis, were observed. Time of addition and attachment studies suggested that the main target for antiviral action of the three carrageenans was virus adsorption, whereas no effect on virus internalization, or early or late protein synthesis was detected. However, the lambda-carrageenan 1T1 was still significantly inhibitory when added any time after adsorption. The pretreatment of virions with the carrageenans showed that 1C1 and 1C3 lacked direct inactivating effect at concentrations near the antiviral IC50 but 1T1 exerted virucidal action. The cyclization of 1T1 to afford the derivative 1T1T1 maintained the antiviral activity but eliminated the virucidal properties. Thus, the structure of 1T1 seems to be responsible for its differential behavior from 1C1 and 1C3, probably allowing a more stable binding to HSV, leading to virion inactivation. In contrast, 1C1 and 1C3 fail to bind with high affinity to virus alone, but are able to interfere with the interaction between HSV particles and the cell. PMID: 10517311 [PubMed - indexed for MEDLINE] Antiviral
properties of fucoidan fractions from Leathesia difformis. Anti-herpes simplex virus activity of
sulfated galactans from the red seaweeds Gymnogongrus griffithsiae and
Cryptonemia crenulata.
Talarico LB, Zibetti RG, Faria PC, Scolaro LA, Duarte ME, Noseda MD, Pujol CA,Damonte EB. Laboratorio de Virologia, Departamento de Quimica Biologica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellon 2, 1428 Buenos Aires, Argentina. This study presents the chemical composition and antiviral activity against herpes simplex virus type 1 (HSV-1) and 2 (HSV-2) of sulfated galactan crude extracts and main fractions obtained from two red seaweeds collected in Brazil, Gymnogongrus griffithsiae and Cryptonemia crenulata. Most of the eighteen tested products, including homogeneous kappa/iota/nu carrageenan and DL-galactan hybrid, exhibited antiherpetic activity with inhibitory concentration 50% (IC50) values in the range 0.5-5.6 microg/ml, as determined in a virus plaque reduction assay in Vero cells. The galactans lacked cytotoxic effects and showed a broad spectrum of antiviral activity against HSV-1 and HSV-2. No direct virus inactivation was observed after virion treatment with the galactans. The mode of action of these compounds could be mainly ascribed to an inhibitory effect on virus adsorption. Most importantly, a significant protection against a murine vaginal infection with HSV-2 was afforded by topical treatment with the sulfated galactans. Copyright 2004 Elsevier B.V. PMID: 15178011 [PubMed - indexed for MEDLINE] 1:
Chemotherapy. 1996 Jan-Feb;42(1):57-64. Links Evaluation of Antiviral Activity of Virucept Red Marine Algae against Herpes Simplex Viruses (HSV)Y. GONG(1), R. ROBERTS(2), I. GADAWSKI(1), D. CHEUNG(1), T. TAM(1), AND S.L. SACKS(1) (1) Viridae Clinical Sciences, Inc. and The University of British Columbia, Vancouver, B.C.(2) Bryant Nutrients, 4133 Greenwell St., Baton Rouge, LA 70805, USA The antiviral effect of Virucept Red Marine Algae (Virucept) against HSV was evaluated in cultured Vero cells using plague reduction assay. The crude extracts containing polysaccharide were prepared by ethanol precipitation. Pre-treatment of cells with the Virucept extracts showed a strong inhibitory effect against both HSV type 1 and 3 with the 90% effective concentrations (EC90) ~0.1% for HSV-1 and 0.01% for HSV-2, respectively. Strong inhibition was also observed even after removing the extracts by washing with PBS on pre-treated cells. Similar activities were examined on HSV Acyclovir-or Forscanet-resistant strains. Approximately 66% inhibition was observed on cells that were already infected with HSV-1. Approximately 20-36% inhibition at a concentration of 0.5% was seen on HSV-2 and Acyclovir-or Forscarnet-resistant HSV infected cells. Our data indicate that the extracts from Virucept Red Marine Algae can be further developed as a vaginal microbicide for preventing HSV infection.Inhibition of Herpesvirus Replication by Marine Algae Extracts Extracts from two species of marine red algae, Cryptosyphonia
Antiviral Activity of Extracts from Marine Algae
JAMES T. RICHARDS, EARL R. KERN, LOWELL A. GLASGOW, JAMES C. OVERALL, JR., E. FRANK DEIGN, AND MELVIN T. HATCH Department of Pediatrics, University of Utah College of Medicine, Salt Lake City, Utah 84132, and Naval Biosciences Laboratory, School of Public Health, University of California, Berkeley, California 94720 Received for publication 2 March 1978 Extracts of two species of marine algae, Constantinea simplex and Farlowia mollis, were tested for antiviral activity in tissue culture and in experimental infections of mice. Treatment of confluent mouse embryo fibroblast cell monolayers with either compound before viral inoculation was effective in inhibiting the replication of herpes simplex virus type 1 and type 2, vaccinia virus, and vesicular stomatitis virus, but not encephalomyocarditis virus, Semiliki Forest virus, or murine cytomegalovirus. Prophylactic administration of these extracts was effective in reducing final mortality or prolonging the mean day of death of animals inoculated by the intraperitoneal, intracerebral, or intranasal routes with herpes simplex virus type 2. When therapy was initiated after viral inoculation or at a site other than that of viral inoculation, no significant effect on mortality or on mean day of death was observed. Neither preparation was effective in mice inoculated intraperitoneally with encepthalomyocarditis virus, Semliki Forest virus, or murine cytomegalovirus or in animals infected intravaginally with herpes simplex virus type 2. The prophylactic but not therapeutic antiviral activity of these preparations seriously limits their potential use in human herpes simplex virus infections. American Society for Microbiology, Vol. 14, No. 4, Copyright 1978
Christopher Scipio |