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SOMETHING ABOUT FOOD

(CAT) and Glutathione Peroxidase (GPx) are Physiological Disorders
responsible for eliminating H O into water and Despite the presence of the cell’s antioxidant defense system to counteract oxidative
2
2
thus preventing the production of OH (Figure damage from ROS, oxidative damage accumulates during the life cycle and has been
•-
1). implicated in numerous age-dependent disorders. As every cell can be attacked by free
Primary antioxidants control the first steps radicals, an overproduction of these species is linked with the development of numerous
of the ROS production cascade. They are the physiological disorders (Figure 3).
first and most important defense live providing These negative effects are compounded with increasingly poor diets and life-style
the best protection against daily oxidative habits, which are not conductive to maintain the natural repair process and antioxidant
attacks, through the control of the upstream network. As the environment tends to strip away the nutrients essential to control the
reactions. Endogenous primary antioxidants production of free radicals, the restoration of the natural antioxidant balance seems to be
play a crucial role in maintaining optimal cellular a proper alternative and convenient method to maintain health. Especially, the restoration
functions and thus systemic health and of our endogenous primary antioxidant levels, which represent the first line of antioxidant
wellbeing. Thanks to their complementary and defenses, could lead to the prevention of numerous human disorders.
synergic mechanism of action against ROS
production, SOD, CAT and GPx prevent the
development of oxidative damages.
Secondary Antioxidants
Secondary antioxidants are externally provided
from dietary sources, such as vitamins (vitamin
C and E), minerals (Se, Cu, Zn, Mn) carotenoids,
uric acid, flavonoids etc. These so-called
secondary antioxidants are active against the
multiple secondary radicals, reducing the
propagation of oxidative damages. In the lipid
bilayer, secondary antioxidants, including
vitamin E, vitamin C and glutathione, can
interact with radicals (ROH), which are stable
and relatively non-reactive. This stability
interrupts the chain reaction. Contrary to primary
antioxidants, secondary antioxidants quench
only one free radical and are quickly exhausted
with no possibility of renewal. In this way,
secondary antioxidant reserves can become
quickly saturated and oxidative stress
uncontrolled. Their protective effect is therefore
less important than primary (Figure 2).

เอกสารอ้างอิง/References
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