RESUMO
Flavonoids and related polyphenols, in addition to their cardioprotective, anti-tumor, anti-inflammatory, anti-carcinogenic and anti-allergic activities, also possess promising anti-HIV effects. Recent studies documented that the beta-chemokine receptors, CCR2b, CCR3 and CCR5, and the alpha-chemokine receptors, CXCR1, CXCR2 and CXCR4 serve as entry coreceptors for HIV-1. Although flavonoids and polyphenolic compounds elicit anti-HIV effects such as inhibition of HIV-1 expression and virus replication, the molecular mechanisms underlying these effects remain to be clearly elucidated. We hypothesize that flavonoids exert their anti-HIV effects, possibly by interfering at the HIV co-receptor level. We investigated the effect of flavonoid constituents of a proprietary grape seed extract (GSE) on the expression of HIV-1 coentry receptors by immunocompetent mononuclear leukocytes. Our results showed that GSE significantly downregulated the expression of the HIV-1 entry co-receptors, CCR2b, CCR3 and CCR5 in normal PBMC in a dose dependent manner. Further, GSE treated cultures showed significantly lower number of CCR3 positive cells as quantitated by flow cytometry analysis which supports RT-PCR gene expression data. Investigations of the mechanisms underlying the anti-HIV-1 effects of grape seed extracts may help to identify promising natural products useful in the prevention and/or amelioration of HIV-1 infection.
Assuntos
Antocianinas/farmacologia , Antioxidantes/farmacologia , HIV-1/efeitos dos fármacos , Leucócitos Mononucleares/efeitos dos fármacos , Proantocianidinas , Receptores de Quimiocinas/efeitos dos fármacos , Vitis/química , Regulação Viral da Expressão Gênica/efeitos dos fármacos , HIV-1/genética , Humanos , Extratos Vegetais/farmacologia , Receptores CCR2 , Receptores CCR3 , Receptores CCR5/efeitos dos fármacos , Receptores CCR5/genética , Receptores de Quimiocinas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sementes/químicaRESUMO
Flavonoids and related polyphenols, in addition to their cardioprotective, anti-tumor, anti-inflammatory, anti-carcinogenic and anti-allergic activities, also possess promising anti-HIV effects. Recent studies documented that the ß-chemokine receptors, CCR2b, CCR3 and CCR5, and the a-chemokine receptors, CXCR1, CXCR2 and CXCR4 serve as entry coreceptors for HIV-1. Although flavonoids and polyphenolic compounds elicit anti-HIV effects such as inhibition of HIV-1 expression and virus replication, the molecular mechanisms underlying these effects remain to be clearly elucidated. We hypothesize that flavonoids exert their anti-HIV effects, possibly by interfering at the HIV co-receptor level. We investigated the effect of flavonoid constituents of a proprietary grape seed extract (GSE) on the expression of HIV-1 coentry receptors by immunocompetent mononuclear leukocytes. Our results showed that GSE significantly downregulated the expression of the HIV-1 entry co-receptors, CCR2b , CCR3 and CCR5 in normal PBMC in a dose dependent manner. Further , GSE treated cultures showed significantly lower number of CCR3 positive cells as quantitated by flow cytometry analysis which supports RT-PCR gene expression data.Investigations of the mechanisms underlying the anti-HIV-1 effects of grape seed extracts may help to identify promising natural products useful in the prevention and /or amelioration of HIV-1 infection