Free radicals are constantly formed in living cells and removed by antioxidant defenses. Antioxidant enzymes are the main line of defense against free radicals in animal and plant cells. Uncontrolled generation ROS are involved in a number of human disease states, including diabetes and cancer due to disturbance in cellular and molecular processes including cell growth, differentiation and proliferation.
Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Critical Care giúp cho các bạn có thêm kiến thức về ngành y học đề tài: Plasma redox status is impaired in the portacaval shunted rat – the risk of the reduced antioxidant ability...
Antioxidant protein 2 (AOP2) is a member of a family of
thiol-specific antioxidants, recently renamedperoxiredoxins,
that evolvedas part of anelaborate systemtocounteract and
control detrimental effects of oxygen radicals. AOP2 is
found in endothelial cells, erythrocytes, monocytes, T andB
cells, but not in granulocytes. AOP2 was found solely in the
cytoplasm and was not associated with the nuclear or
membrane fractions; neither was it detectable in plasma.
unabsorbed polyphenols may play a role in the protection of the GI tract against RONS
prior to their fecal excretion. In contrast to native polyphenols, less data exists on the
antioxidant activity of bioavailable polyphenol phase II metabolites (conjugated
everal advantageous effects of vitamin C on human health have
been stressed, such as the relationship between high plasma vitamin C concentration and
reduced gastric cancer risk found in EPIC study (Jenab et al., 2006). Besides the antioxidant
activity of vitamin C, which may explain its protective role against gastric cancer risk,
several other activities could play a role, such as its ability to modulate cell growth kinetics
and its putative antimicrobial activity, for example against Helicobacter pylori, a bacteria
responsible for chronic ulcer and even stomach cancer.
We reported earlier that urate may behave as a pro-oxidant in Cu
-induced oxidation of diluted plasma.
Thus,its effect on Cu
-induced oxidation of isolated
low-density lipoprotein (LDL) was investigated by mon-itoring the formation of malondialdehyde and conjugated
dienes and the consumption of urate and carotenoids. We
show that urate is antioxidant at high concentration but
pro-oxidant at low concentration.