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Skip to 0 minutes and 16 seconds Hi, my name is Wiesław Wiczkowski and I would like to tell you about the possible effect of antioxidants on the brain. Well, the brain, due to the high degree of oxygen utilization, a high level unsaturated fatty acids and transition metals, for example irons, as well as relatively weak mechanisms of antioxidant defense, is particularly susceptible to oxidative damage. Thus, the excessive accumulation of reactive oxygen species and lipid peroxidation products in the brain, which are constantly produced in vivo, may be in part responsible for pathogenesis of neurological disorders, such as dementia as well Parkinson’s as Alzheimer’s disease. The last one is the most common cause of dementia among the elderly.

Skip to 1 minute and 14 seconds Fortunately, they are biologically active compounds called antioxidants which may favorably influence the nerve cells. Among them, flavonoids are the most common natural compounds processing strong antioxidant properties. In addition, what is important to emphasize, flavonoids are very often consumed with foods of plant origin and are absorbed into the blood and thus may affect the consumers body. However, to reach the brain cells, consumed absorbed flavonoids and their metabolites, must first pass through the brain barrier such as blood-brain barrier (BBB) or the blood-cerebrospinal fluid barrier. The purpose of these barriers is to ensure the stability of the environment of neurons present in the central nervous system.

Skip to 2 minutes and 13 seconds They are responsible for the protection against toxic substances and the effects of sudden changes in the blood levels of different substances for example hormones and xenobiotics. In case of food flavonoids, there is evidence that quercetin, which onion is the richest source, passes through the blood-cerebrospinal fluid barrier, probably as a result of simple diffusion. It was also shown that the soy isoflavones such as genistein, daidzein, and their metabolites - equol and p-ethylphenol, may pass through the blood-cerebrospinal fluid barrier in the participation of the thyroid hormone transporter. In contrast, the other common flavonoid - tea catechin, could not pass the blood-cerebrospinal fluid barrier.

Skip to 3 minutes and 14 seconds It is supposed that the polarity of this compound is the main factor that has limited the penetration of this compound through the brain barrier. Then, after the penetration through the brain barrier, the mechanism of flavonoids action related to antioxidant properties, apart from directly participating in the redox reactions, may also concern the induction of endogenous antioxidants and detoxifying enzymes. Therefore, after penetration into the environment of nerve cells flavonoids with antioxidant properties may protect neurons from damage arising during uncontrolled oxidation and other neurodegenerative processes by scavenging harmful substances or stimulating protective endogenous processes.

Skip to 4 minutes and 12 seconds Unfortunately, even though a number of studies devoted to role of antioxidants in the prevention of neurodegenerative disease have been published, many hypotheses and observations have still not been successfully verified yet. Summing up. The excessive accumulation of reactive oxygen species and lipid peroxidation products in the brain may be in part responsible for the development of neurological disorders. Some food flavonoids, for example quercetin or isoflavones, penetrate through the brain barrier and may protect the nerve cells. The mechanisms of flavonoids action may be directly involved in the redox reaction as well as may also concern the inductions of endogenous antioxidants and detoxifying enzymes.

The effect of antioxidants on the brain

How antioxidants present in our diet influence the brain function?

In this video Wiesław Wiczkowski discusses the role of common dietary antioxidants, such as flavonoids, in the maintenance of brain functions. He points to the mechanisms of antioxidants passing through brain barriers, and their role in protecting neurons from damage.

So, theoretically antioxidants, including flavonoids, could be effective in the prevention of the neurological disorders. Do you think diet can protect against neurological disorders? Please let us know your ideas and thought in your comments to this video.

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Food for Thought: The Relationship Between Food, Gut and Brain

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