Inhibitory effects of helenalin and related compounds on 5-lipoxygenase and leukotriene C(4) synthase in human blood cells.
Biochem Pharmacol
; 62(7): 903-11, 2001 Oct 01.
Article
em En
| MEDLINE
| ID: mdl-11543725
ABSTRACT
The sesquiterpene lactone helenalin, which can be isolated from several plant species of the Asteraceae family, is a potent anti-inflammatory and antineoplastic agent. In agreement, alcohol extracts of these plants are used for local external treatment of inflammatory conditions. Since leukotrienes are important mediators in inflammatory processes, the inhibitory effects of helenalin and some derivatives on leukotriene (LT) biosynthesis were studied. Treatment of human platelets with helenalin provoked irreversible inhibition of LTC(4) synthase in a concentration- and time-dependent manner with an IC(50) of 12 microM after a 60 min preincubation. 11alpha,13-Dihydrohelenalin acetate was less potent. Interestingly, individual donors could be divided into two distinct groups with respect to the efficacy of helenalin to suppress platelet LTC(4) synthase. In human granulocytes, helenalin inhibited both the 5-lipoxygenase (IC(50) 9 microM after 60 min preincubation) and LTC(4) synthase in a concentration- and time-dependent fashion. In contrast, the drug was without effect on LTA(4) hydrolase. The GSH-containing adducts (2beta-(S-glutathionyl)-2,3-dihydrohelenalin and 2beta-(S-glutathionyl)-2,3,11alpha,13-tetra hydrohelenalin acetate) did not significantly inhibit LTC(4) synthase. The present results indicate a mechanism for the anti-inflammatory effect of helenalin and related compounds.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Sesquiterpenos
/
Plaquetas
/
Araquidonato 5-Lipoxigenase
/
Inibidores da Agregação Plaquetária
/
Glutationa Transferase
/
Granulócitos
Limite:
Humans
Idioma:
En
Ano de publicação:
2001
Tipo de documento:
Article