Viruserkrankungen

Artemisia annua Leaf Extracts against Pathogenic Bacteria

Antimicrobial Activity of Artemisia annua
Leaf Extracts against Pathogenic Bacteria
Ahmad Tajehmiri, Fahimeh Issapour, Mina Nasiri Moslem, Maryam
Tavakoli Lakeh and Masoud Hassani Kolavani

Medical Biology Research Center
Kermanshah University of Medical Sciences, Kermanshah, Iran

Department of Microbiology, College of Microbiology Science, Lahijan Branch,
Islamic Azad University, Lahijan, Iran - Corresponding author




Beyond malaria: The inhibition of viruses by artemisinin-type compounds

Abstract

Natural products represent valuable chemical scaffolds for drug development. A recent success story in this context was artemisinin, which is not only active against malaria but also to other diseases. This raised the interest of artemisinin's potential for drug repurposing. On the present review, we give an overview on artemisinin's antiviral activity. There is good in vitro and in vivo evidence for the activity of artemisinin and its derivatives against DNA viruses of the Herpesviridae and Hepadnaviridae families such as cytomegaloviruses, human herpesvirus 6, herpes simplex viruses 1 and 2, Epstein-Barr virus and Hepatitis B virus. The evidence is weaker for Polyomaviruses and papilloma viruses. Weaker or no inhibitory activity in vitro has been reported for RNA viruses such as human immunodeficiency viruses 1 and 2, hepatitis C virus, influenza virus and others. Interestingly, the artemisinin derivative artesunate did not exert cross-resistance to ganciclovir-resistant HCMV and exerted synergistic inhibition in combination with several clinically established antiviral standard drugs. The antiviral activity of first generation artemisinin derivatives (e.g. artesunate, artemether, etc.) was enhanced by novel derivatives, including dimer and trimer molecules. First results on patients indicating activity in a subset of HCMV patients. Novel developments in the field of nanotechnology and synthetic biology to bioengineer microorganisms for artemisinin production may pave the way for novel drugs to fight viral infections with artemisinin-based drugs.



Chloroquine is a potent inhibitor of SARS coronavirus infection and spread

Severe acute respiratory syndrome (SARS) is caused by a newly discovered coronavirus (SARS-CoV). No effective prophylactic or post-exposure therapy is currently available. We report, however, that chloroquine has strong antiviral effects on SARS-CoV infection of primate cells. These inhibitory effects are observed when the cells are treated with the drug either before or after exposure to the virus, suggesting both prophylactic and therapeutic advantage. In addition to the well-known functions of chloroquine such as elevations of endosomal pH, the drug appears to interfere with terminal glycosylation of the cellular receptor, angiotensin-converting enzyme 2. This may negatively influence the virus-receptor binding and abrogate the infection, with further ramifications by the elevation of vesicular pH, resulting in the inhibition of infection and spread of SARS CoV at clinically admissible concentrations. Chloroquine is effective in preventing the spread of SARS CoV in cell culture. Favorable inhibition of virus spread was observed when the cells were either treated with chloroquine prior to or after SARS CoV infection. In addition, the indirect immunofluorescence assay described herein represents a simple and rapid method for screening SARS-CoV antiviral compounds.

 

Forum on Immunopathological Diseases and Therapeutics

DOI: 10.1615/ForumImmunDisTher.2012004378
pages 1-13

Coronaviral Ion Channels as Target for Chinese Herbal Medicine

Silvia Schwarz
Shanghai Research Center for Acupuncture & Meridians, 199 Guoshoujing Rd, Shanghai 201203, China
Daniel Sauter
Shanghai Research Center for Acupuncture & Meridians, 199 Guoshoujing Rd, Shanghai 201203, China ; Institute for Biophysics, JW-Goethe-University, Max-von-Laue Str. 1, 60438 Frankfurt a.M., Germany
Wei Lu
Max-Planck Intitute for Biophysics, Max-von-Laue Str. 3, 60438 Frankfurt a.M., Germany
Kai Wang
Key Laboratory of Molecular Virology & Immunology, Institut Pasteur of Shanghai, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200025, China
Bing Sun
Key Laboratory of Molecular Virology & Immunology, Institut Pasteur of Shanghai, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200025, China
Thomas Efferth
Department of Pharmaceutical Biology Institute of Pharmacy and Biochemistry Johannes Gutenberg University, Mainz, Germany
Wolfgang Schwarz
Shanghai Research Center for Acupuncture & Meridians, 199 Guoshoujing Rd, Shanghai 201203, China; Max-Planck Intitute for Biophysics, Max-von-Laue Str. 3, 60438 Frankfurt a.M., Germany;3Institute for Biophysics, JW-Goethe-University, Max-von-Laue Str.

ABSTRACT

A variety of viruses encode for proteins that can form ion channels in the membrane of infected cells. For example, the protein coded by the open-reading-frame 3a of SARS coronavirus (SARS-CoV) has been demonstrated to form a cation-selective channel that may become expressed in the infected cell, and its activation is then involved in virus release. Chinese herbal drugs that inhibit the ion channel formed by the 3a protein can be expected to inhibit virus release, and therefore they are a source for the development of novel therapeutic agents. Various drugs found in Chinese herbs are well known as anticancer agents and also have antiviral potency. In one study we tested some of them with respect to their potency to block the 3a channel. Application of the anthraquinone emodin was used as adjunct therapy in treatment of SARS, and we have demonstrated that it can inhibit the 3a ion channel as well as virus release with a K1/2 value of approximately 20 µM. Also the flavonols kaempferole and kaempferole glycosides may be potent inhibitors of the 3a channels. On the other hand, the favonol quercitin seems not to be effective. In addition, the flavanon naringenin and the isoflavon genistein were ineffective in inhibiting 3a-mediated currents. Antiviral activity of the artemisinin derivative artesunate is well documented, but we did not detect any inhibition of 3a-mediated currents. We suggest that viral ion channels, in general, may be good targets for the development of antiviral agents, and that, in particular, emodin and kaempferol gycosides are good candidates for 3a channel proteins in coronaviruses.

 

Hepatitis B - Hepatitis C


Efficacy of Artemisia annua polysaccharides as an adjuvant to hepatitis C vaccination.

Abstract

The traditional Chinese medicine Artemisia annua can prevent and treat hepatitis following an unclear mechanism. The aim of this study was to evaluate the effects of A. annua polysaccharides (AAP) on hepatitis C virus (HCV). A pcDNA3.1/NS3 expression vector was constructed. Ninety female BALB/c mice were randomly divided into six groups: high-dose AAP (1 mg/mL) + HCV/NS3 plasmid; middle-dose AAP (0.5 mg/mL) + HCV/NS3 plasmid; low-dose AAP (0.1 mg/mL) + HCV/NS3 plasmid; HCV/NS3 plasmid; high-dose AAP (1 mg/mL); normal saline control (N = 15). Except the control group and the high-dose AAP group, other groups were inoculated with 50 μg pcDNA3.1-HCV/NS3 plasmid. Serum antigenic-specific antibody was detected after the last immunization, and the levels of secreted IFN-γ and IL-4 were measured. pcDNA3.1/NS3 plasmid was successfully constructed, and the extracted product contained HCV/NS3 sequence. Compared with single inoculation with HCV/NS3 DNA vaccine, the specific antibody levels induced by middle-dose AAP plus HCV/NS3 DNA vaccine were significantly different in weeks 1, 3 and 5 (P < 0.05). However, there were no significant differences in the antibody levels induced by high-dose and low-dose AAP as adjuvant compared with those of single inoculation with DNA vaccine (P > 0.05). The level of serum IFN-γ secretion was significantly higher than that of IL-4 secretion. Compared with the single HCV/NS3 DNA vaccine group, AAP plus HCV/NS3 DNA vaccine groups had significant increased IFN-γ levels (P < 0.05), but the IL-4 levels were not significantly different among these groups (P > 0.05). AAP, as the adjuvant of HCV/NS3 DNA vaccine, can widely regulate the humoral immunity and cellular immune function of normal and cyclophosphamide-induced immunocompromised mice. AAP can promote IFN-γ secretion probably by inducing Th1-type cellular immune response.

more


Traditional Chinese medicine commands a unique position among all traditional medicines because of its 5000 years of history. Our own interest in natural products from traditional Chinese medicine was triggered in the 1990s, by artemisinin-type sesquiterpene lactones from Artemisia annua L. As demonstrated in recent years, this class of compounds has activity against malaria, cancer cells, and schistosomiasis. Interestingly, the bioactivity of artemisinin and its semisynthetic derivative artesunate is even broader and includes the inhibition of certain viruses, such as human cytomegalovirus and other members of the Herpesviridae family (e.g., herpes simplex virus type 1 and Epstein-Barr virus), hepatitis B virus, hepatitis C virus, and bovine viral diarrhea virus. Analysis of the complete profile of the pharmacological activities and molecular modes of action of artemisinin and artesunate and their performance in clinical trials will further elucidate the full antimicrobial potential of these versatile pharmacological tools from nature.





Ethnopharmacology in overdrive: the remarkable anti-HIV activity of Artemisia annua.

Ethnopharmacology in overdrive: the remarkable anti-HIV activity of Artemisia annua. - PubMed - NCBI








Der Extrakt aus der Zistrose


© hainichfoto I © sculder1909 - Fotolia.comStark, natürlich und nebenwirkungsfrei:

Übereinstimmend empfehlen Wissenschaftler wie Prof. Stephan Ludwig, Prof. Oliver Planz (Uni Tübingen), Prof. Jens Träder (Lübeck) und Prof. Dr. Dr. Dr. Gundolf Keil (Würzburg) den Extrakt aus der Zistrose, „Cystus 052“. Die Forscher befürworten, diesen bereits vorbeugend einzusetzen. Das trifft sich gut, denn parallel rät mittlerweile auch die WHO, auf natürliche Mittel umzusteigen.


Extrakte aus der Zistrose: Antivirale Aktivität gegen HIV und Ebolaviren in Zellkulturen

Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

Der Extrakt aus der Zistrose


Extrakte aus der Zistrose: Antivirale Aktivität gegen HIV und Ebolaviren in Zellkulturen


Potent in vitro antiviral activity of Cistus incanus extract against HIV and Filoviruses targets viral envelope proteins


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Artemisinin Analogues as Potent Inhibitors of In Vitro Hepatitis C Virus Replication


Artemisinin Analogues as Potent Inhibitors of In Vitro Hepatitis C Virus Replication

Herbal Artemisia cures dengue!








Bakterielle Infektionen



WELT ONLINE: 

Arznei-Pflanze wirkt besser als ihr Medikament

Für die Herstellung eines Anti-Malaria-Mittels musste dessen Wirkstoff bisher aufwendig aus der Artemisia-Pflanze isoliert werden. Allerdings könnte die Einnahme der Blätter sehr viel effektiver sein.
Die Artemisia-Pflanze hilft möglicherweise weit besser gegen Malaria als das auf diesem Kraut beruhende Medikament. Eine US-Studie an Mäusen zeigt, dass die zermahlenen Blätter der Pflanze die Malaria-Erreger eher abtöten als die Arznei.
Dies könne die Malaria-Therapie wesentlich günstiger machen und Entwicklungsländern auch eine ökonomische Perspektive bieten, schreiben die Forscher um Stephen Rich von der University of Massachusetts in Amherst in der Zeitschrift "Plos One".

Hunderttausende Malaria-Tote pro Jahr

Hunderte Millionen Menschen sind weltweit mit Malaria-Parasiten der Gattung Plasmodium infiziert. Im Jahr 2009 starben nach Angaben der Weltgesundheitsorganisation (WHO) mindestens rund 800 000 Menschen an der Krankheit.
Zur Behandlung eingesetzt werden vor allem auch Präparate mit dem Wirkstoff Artemisinin, der auf dem Einjährigen Beifuß (Artemisia annua) beruht. Zur Herstellung wird Artemisinin aus der Pflanze in einem aufwendigen Prozess isoliert. Die Medikamente, die oft noch mit anderen Arzneien kombiniert werden, sind gerade für Entwicklungsländer zu teuer. Daher prüften die Forscher, wie gut die natürliche Pflanze gegen die Infektionskrankheit hilft.
Dazu verglichen sie die Wirkung von reinem Artemisinin und getrockneten zermahlenen Blättern an Mäusen, die den Erreger Plasmodium chabaudi trugen. Dieser befällt zwar Nagetiere, teilt aber sehr viele Eigenschaften mit den Erregern, die den Menschen heimsuchen.
Nach der Einnahme tötete das Naturprodukt in den Tiere im Zeitraum von 12 bis 72 Stunden deutlich mehr Parasiten ab als reines Artemisinin – bei gleichem Wirkstoffgehalt.

40 Mal mehr Artemisinin im Blut

Die Forscher führen dies zum einen darauf zurück, dass nach Gabe des Pflanzenmittels im Vergleich zum Pharmaprodukt etwa 40 Mal mehr Artemisinin im Blut der Tiere zirkulierte. Zusätzlich verweisen sie darauf, dass in den Blättern der Pflanze neben Artemisinin auch andere Substanzen vorkommen, die gegen Malaria helfen.
"Die Blätter von Artemisia enthalten eine Vielzahl von Stoffen, die interessant sind wegen ihrer offenkundigen, aber schwächeren Wirkung gegen Malaria", sagt die an der Studie beteiligte Biologin Pamela Waethers vom Worcester Polytecnic Institute in einer Mitteilung ihres Instituts, "dazu zählen mindestens sechs Flavonoide, von denen gezeigt wurde, dass sie mit Artemisinin zusammenwirken, um Malaria-Parasiten abzutöten." Die Stoffe könnten sich in ihrer Wirkung gegenseitig verstärken, schreiben die Forscher.
Sie betonen, der Einsatz zermahlener Blätter sei auch wesentlich kostengünstiger als der Kauf teurer Medikamente. "Artemisia kann in den meisten Klimazonen gut angebaut werden", sagt Weathers. Die Blätter könnten gut geerntet, getrocknet, auf ihren Wirkstoffgehalt untersucht und in Kapseln verpackt werden. Dies könnte Menschen in Entwicklungsländern eine Perspektive geben und dort die Wirtschaft anregen.
dpa/fwt/shl
Die riskantesten Krankheitserreger

Dog vaccinations in Bali
Die Tollwut ist eine Infektion durch Viren, die durch Tierbisse übertragen werden. Häufig sind Hunde und Katzen oder Flughunde in Südostasien (vor allem auf der Insel Bali) mit dem Virus infiziert. Auf Sri Lanka sind seit Beginn des Jahres 28 Personen an Tollwut gestorben. Die Behörden in Peru bestätigen sechs Fälle von Tollwut in der Region Puno, Nigeria meldet acht Todesfälle aus dem Bundesstaat Cross River.
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Foto: picture alliance /dpa