Tè verde anti HIV ?!

LiborioAsahi · **Tè verde anti HIV ?! -** 12-01-2011, 11:38 AM

Epigallocatechin gallate, the main polyphenol in green tea, binds to the T-cell receptor, CD4: Potential for HIV-1 therapy.

Abstract

BACKGROUND: The green tea flavonoid, epigallocatechin gallate (EGCG), has been proposed to have an anti-HIV-1 effect by preventing the binding of HIV-1 glycoprotein (gp) 120 to the CD4 molecule on T cells.

OBJECTIVE: To demonstrate that EGCG binds to the CD4 molecule at the gp120 attachment site and inhibits gp120 binding at physiologically relevant levels, thus establishing EGCG as a potential therapeutic treatment for HIV-1 infection.

METHODS: Nuclear magnetic resonance spectroscopy was used to examine the binding of EGCG and control, (-)-catechin, to CD4-IgG2 (PRO 542). Gp120 binding to human CD4+ T cells was analyzed by flow cytometry.

RESULTS: Addition of CD4 to EGCG produced a linear decrease in nuclear magnetic resonance signal intensity from EGCG but not from the control, (-)-catechin. In saturation transfer difference experiments, addition of 5.8 micromol/L CD4 to 310 micromol/L EGCG produced strong saturation at the aromatic rings of EGCG, but identical concentrations of (-)-catechin produced much smaller effects, implying EGCG/CD4 binding strong enough to reduce gp120/CD4 binding substantially. Molecular modeling studies suggested a binding site for EGCG in the D1 domain of CD4, the pocket that binds gp120. Physiologically relevant concentrations of EGCG (0.2 micromol/L) inhibited binding of gp120 to isolated human CD4+ T cells.

CONCLUSION: We have demonstrated clear evidence of high-affinity binding of EGCG to the CD4 molecule with a Kd of approximately 10 nmol/L and inhibition of gp120 binding to human CD4+ T cells.

CLINICAL IMPLICATIONS: Epigallocatechin gallate has potential use as adjunctive therapy in HIV-1 infection.

LiborioAsahi · 12-01-2011, 11:38 AM

Epigallocatechin gallate, the main polyphenol in g... [J Allergy Clin Immunol. 2006] - PubMed result

LiborioAsahi

Stop a vaccini vaiolo forse causa boom casi HIV anni'70 - Scienza e Medicina - ANSA.it

Strumenti Discussione
Visualizza Versionee Stampabile Invia Pagina via Email
Modalità Visualizzazione
Modalità lineare In Modo Ibrido In Modalità elencata

	(#1)
LiborioAsahi All the Truth Member Messaggi: 15,115 Data registrazione: Sep 2008 Località: Mvtina Età: 40	Tè verde anti HIV ?! - 12-01-2011, 11:38 AM Tè verde anti HIV ?! Epigallocatechin gallate, the main polyphenol in green tea, binds to the T-cell receptor, CD4: Potential for HIV-1 therapy. Abstract BACKGROUND: The green tea flavonoid, epigallocatechin gallate (EGCG), has been proposed to have an anti-HIV-1 effect by preventing the binding of HIV-1 glycoprotein (gp) 120 to the CD4 molecule on T cells. OBJECTIVE: To demonstrate that EGCG binds to the CD4 molecule at the gp120 attachment site and inhibits gp120 binding at physiologically relevant levels, thus establishing EGCG as a potential therapeutic treatment for HIV-1 infection. METHODS: Nuclear magnetic resonance spectroscopy was used to examine the binding of EGCG and control, (-)-catechin, to CD4-IgG2 (PRO 542). Gp120 binding to human CD4+ T cells was analyzed by flow cytometry. RESULTS: Addition of CD4 to EGCG produced a linear decrease in nuclear magnetic resonance signal intensity from EGCG but not from the control, (-)-catechin. In saturation transfer difference experiments, addition of 5.8 micromol/L CD4 to 310 micromol/L EGCG produced strong saturation at the aromatic rings of EGCG, but identical concentrations of (-)-catechin produced much smaller effects, implying EGCG/CD4 binding strong enough to reduce gp120/CD4 binding substantially. Molecular modeling studies suggested a binding site for EGCG in the D1 domain of CD4, the pocket that binds gp120. Physiologically relevant concentrations of EGCG (0.2 micromol/L) inhibited binding of gp120 to isolated human CD4+ T cells. CONCLUSION: We have demonstrated clear evidence of high-affinity binding of EGCG to the CD4 molecule with a Kd of approximately 10 nmol/L and inhibition of gp120 binding to human CD4+ T cells. CLINICAL IMPLICATIONS: Epigallocatechin gallate has potential use as adjunctive therapy in HIV-1 infection.

	(#2)
LiborioAsahi All the Truth Member Messaggi: 15,115 Data registrazione: Sep 2008 Località: Mvtina Età: 40	12-01-2011, 11:38 AM Epigallocatechin gallate, the main polyphenol in g... [J Allergy Clin Immunol. 2006] - PubMed result

	(#3)
LiborioAsahi All the Truth Member Messaggi: 15,115 Data registrazione: Sep 2008 Località: Mvtina Età: 40	La vaccinazione riduce di 5 volte la capacità di moltiplicazione del virus - 12-01-2011, 11:50 AM Stop a vaccini vaiolo forse causa boom casi HIV anni'70 - Scienza e Medicina - ANSA.it