Flavonoids of Honey and Propolis:  Characterization and Effects on Hepatic Drug-Metabolizing Enzymes and Benzo[a]pyrene−DNA Binding in Rats

Abstract

The influence of dietary sunflower honey, propolis, and a flavonoid extract of propolis was examined on drug-metabolizing enzyme activities in rat liver and on microsome-mediated binding of benzo[a]pyrene to DNA. Characterization of flavonoids present in sunflower honey and propolis was achieved in order to assess the relative effects of different components of honey and propolis. Honey and propolis contained the same major flavonoids, pinocembrin, chrysin, galangin, and pinobanksin. The concentration of flavonoids was higher in propolis. Sunflower honey produced no significant changes on phase I and phase II enzyme activities and no modification of in vitro binding of benzo[a]pyrene to DNA. Propolis treatment produced an increase of ethoxyresorufin deethylase, pentoxyresorufin depentylase, ethoxycoumarin deethylase, glutathione transferase, and epoxide hydrolase activities. A flavonoid extract from propolis slightly enhanced only few enzyme activities, ethoxycoumarin deethylase and epoxide hydrolase. The induction pattern was similar to that observed with pinocembrin (a major flavonoid of propolis) administered solely. Binding of benzo[a]pyrene to DNA by microsomes from rats fed with propolis or a flavonoid extract from propolis was not significantly modified. These results contribute to identification of food or foodstuffs that can modify drug-metabolizing enzymes and binding of carcinogens to DNA. Keywords: Sunflower honey; propolis; flavonoids; drug-metabolizing enzymes; benzo[a]pyrene−DNA binding

Flavonoid-induced glutathione depletion: Potential implications for cancer treatment

“…This is likely the case of HCs, apigenin, genistein, and chrysin, where their cytotoxicity may result from a combination of interference with the mitochondrial respiratory chain and MRP-mediated GSH depletion [4][5][6]10]. It is worth noting that the bee product propolis, which is known to exert antimicrobial, antiviral, and cancer preventive properties, contains chrysin, a poor antioxidant, as one of its major components [54].…”

Cytotoxic constituents of propolis inducing anticancer effects: a review

“…[50,51] It possesses anti-inflammatory, anticancer, anti-allergic, anti-anxiolytic and antioxidant properties, and disturbs cell cycle progression. [52][53][54][55][56] However, the mechanism by which chrysin inhibits cancer cell growth and the intracellular pathways remain poorly understood.…”

Effects of the Flavonoid Chrysin on Nitrofurantoin Pharmacokinetics in Rats: Potential Involvement of ABCG2

“…The flavonoid chrysin (5,7-dihydroxyflavone) is present at high levels in honey and propolis (Siess et al, 1996) and in many plant extracts (Williams et al, 1997). In addition to its reported anticarcinogenic (Cardenas et al, 2006), antiviral (Critchfield et al, 1996), antioxidant (Lapidot et al, 2002), and anti-inflammatory (Cho et al, 2004) activities, chrysin has been shown as a potent inhibitor of aromatase (Jeong et al, 1999), an enzyme responsible for the conversion of androstenedione and testosterone into estrone and estradiol, respectively (Meinhardt and Mullis, 2002).…”