M Číž1,2, Martina Pavelková1,2, Lucie Gallová1,2, Jarmila Králová1,2, Lukáš Kubala1,2, Antonı́n Lojek1,2
1Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czech Republic
2Milan Číž, Institute of Biophysics, Academy of Sciences of the Czech Republic, Královopolská 135, 612 65 Brno, Czech Republic.
Tóm tắt
The aim was to study the antioxidant properties of four wine
polyphenols (flavonoids catechin, epicatechin, and quercetin, and
hydroxystilbene resveratrol). All three flavonoids exerted
significant and dose-dependent scavenging effects against
peroxyl radical and nitric oxide in chemical systems. The
scavenging effect of resveratrol was significantly lower. All
polyphenols decreased production of reactive oxygen species
(ROS) by RAW264.7 macrophages. Only quercetin quenched ROS
produced by lipopolysaccharide-stimulated RAW264.7
macrophages incubated for 24 h with polyphenols. Quercetin and
resveratrol decreased the release of nitric oxide by these cells in
a dose-dependent manner which corresponded to a decrease in
iNOS expression in the case of quercetin. In conclusion, the
higher number of hydroxyl substituents is an important structural
feature of flavonoids in respect to their scavenging activity
against ROS and nitric oxide, while C-2,3 double bond (present in
quercetin and resveratrol) might be important for inhibition of
ROS and nitric oxide production by RAW 264.7 macrophages.
