title: Argentine plant extracts active against polymerase and ribonuclease H activities of HIV-1 reverse transcriptase.
abstract: Lipophilic and hydrophilic extracts of four Argentine plants (Gamochaeta simplicaulis Cabr. 1, Achyrocline flaccida Wein. D. C. 2, Eupatorium buniifolium H. et A. 3, and Phyllanthus sellowianus Muell. Arg. 4) were examined in vitro for their ability to inhibit the polymerase and ribonuclease H (RNase H) activities of human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) (wild and Y181C mutant types). The active extracts were also examined as inhibitors of viral replication in HLT4LacZ-1IIIB cell cultures, evaluating their cytotoxicity in parallel. Infusions 2I and 4I, among the crude extracts, showed the highest activity. These extracts were refractioned into four fractions; 2I4 and 4I4 were active as inhibitors of DNA-polymerase (wild and Y181C types) and RNase H activities. These fractions were potent as inhibitors of viral replication and were not cytotoxic. Refractionation of 2I4 yielded five new fractions, two of which, 2I4-4 and 2I4-5, showed notable activity. Refractionation of 4I4 yielded for new fractions; of these, 4I4-3 and 4I4-4 were active. The marked biological activity found in the infusion of A. flaccida and P. sellowianus makes them sufficiently attractive to be considered in the combined chemotherapy of the disease.
authors.affiliation: IQUIMEFA (Instituto de Química y Metabolismo del Fármaco) UBA-CONICET, Cátedra de Farmacognosia, Facultad de Farmacia y Bioquímica, Buenos Aires, República Argentina.
authors.forename: O
authors.initials: O
authors.lastname: Hnatyszyn
authors.forename: A
authors.initials: A
authors.lastname: Broussalis
authors.forename: G
authors.initials: G
authors.lastname: Herrera
authors.forename: L
authors.initials: L
authors.lastname: Muschietti
authors.forename: J
authors.initials: J
authors.lastname: Coussio
authors.forename: V
authors.initials: V
authors.lastname: Martino
authors.forename: G
authors.initials: G
authors.lastname: Ferraro
authors.forename: M
authors.initials: M
authors.lastname: Font
authors.forename: A
authors.initials: A
authors.lastname: Monge
authors.forename: J J
authors.initials: JJ
authors.lastname: Martínez-Irujo
authors.forename: M
authors.initials: M
authors.lastname: Sanromán
authors.forename: M T
authors.initials: MT
authors.lastname: Cuevas
authors.forename: E
authors.initials: E
authors.lastname: Santiago
authors.forename: J J
authors.initials: JJ
authors.lastname: Lasarte
mesh_terms: D019380:Anti-HIV Agents / Q000494:pharmacology; D002460:Cell Line; D004259:DNA-Directed DNA Polymerase / Q000378:metabolism; D054303:HIV Reverse Transcriptase / Q000037:antagonists & inhibitors*; D006801:Humans; D019384:Nucleic Acid Synthesis Inhibitors; D010936:Plant Extracts / Q000494:pharmacology*; D010946:Plants, Medicinal / Q000737:chemistry*; D018894:Reverse Transcriptase Inhibitors / Q000494:pharmacology*; D016914:Ribonuclease H / Q000037:antagonists & inhibitors* / Q000378:metabolism
chemical_list: D019380:Anti-HIV Agents; D019384:Nucleic Acid Synthesis Inhibitors; D010936:Plant Extracts; D018894:Reverse Transcriptase Inhibitors; D054303:HIV Reverse Transcriptase; D004259:DNA-Directed DNA Polymerase; D016914:Ribonuclease H