“This is good for free radicals.” – a phrase that is certainly common in everyday language. But what is the scientific basis behind this statement and is there something or someone that captures these radicals? Yes, these substances are called antioxidants. On the one hand, there are natural antioxidants such asVitaminsIn addition, there are substances that have an antioxidant effect indirectly, i.e. via one or more other molecules:Nrf2 activatorsAs a potent, broad-spectrum antioxidant,Resveratrolinto focus.
Before we delve into the depths of functional molecules, let us take a look at what an antioxidant actually is. In the expert’s words, the definition is as follows: “Antioxidants are chemical compounds that Oxidation of other substances or prevent them altogether." Unfortunately, this doesn't help a non-expert at all. But it's understandable.
The term antioxidants
An antioxidant is first and foremost “anti” – that is, negatively disposed towards someone or something. The second part of the word, -oxidans, tells us who it is directed towards. This stands for oxygen radicals. These are molecules that contain oxygen and are very “reactive” in the context of our body. This means that due to their chemical makeup, these molecules would very much like to form a bond with another molecule – regardless of whether they are already in a bond or not. In keeping with the motto “whatever the cost”, these radicals have the ability to break existing bonds, which naturally causes damage. A bit like the bad boy who wants to steal the gentleman’s wife. For situations like this, the body has antioxidants that bind these radicals and thus render them harmless.
The classic antioxidants include Vitamin A, Vitamin C and Vitamin E, as well as beta-carotene and Selenium The market for these vitamins as dietary supplements is huge. However, the disappointment was just as great when studies on large populations were examined. Researchers came to the conclusion that there is no evidence that healthy people have any benefit from taking antioxidant vitamins. On the contrary: negative effects were also sometimes seen. So all that glitters is not gold.
Resveratrol and the French Paradox
Now let’s take a closer look at a promising antioxidant:ResveratrolMany people know this substance in connection with the "French Paradox": Despite consuming alcohol and fat, the French live longer than Germans or Americans. The frequency of heart attacks is only a third as high as in the USA. Is it all because of resveratrol? There is no consensus among doctors about the existence of this paradox.
Nevertheless, numerous studies have described many positive effects of resveratrol. In animal models, a dose-dependent anti-cancer effect and a general chemoprotective effect were found. A positive effect on heart cells and a modulating effect on fat metabolism were also demonstrated in cell cultures. In high concentrations, one study showed a reduction in systolic blood pressure. The list of positive effects of resveratrol on health is even longer. The molecule, which has been relatively widely researched over time, occurs naturally primarily in red grapes. In addition, resveratrol was also able to activate Nrf2 in animal models. This brings us to the indirect antioxidants.
What is a transcription factor?
Nrf2 is a transcription factor. To make this term a little more understandable, here is a short digression:
DNA is the blueprint for our body. This blueprint has a number of different chapters or sections, which are referred to in biology as genes. These genes contain "recipes" for proteins and other molecules that are needed for a functioning household in the body. If the body wants to produce a protein, the recipe must first be "copied" or, in technical jargon, transcribed. This is where transcription factors come into play. A transcription factor is basically a factor that can have a positive or negative effect on the "copying". In this way, Nrf2 regulates over 300 genes that are involved in the modulation of inflammation and oxidative stress. The transcription factor plays a central role in the induction of cell-protective genes in response to oxidative stress - in other words, it provides an umbrella when there is a heavy rainfall. A true friend and helper.
Xenobiotics – an effect or no effect?
Nrf2 can be activated by certain substances.ResveratrolWe have already learned about the potent Nrf2 activator from grapes. Medicine speaks of some other substances as xenobiotics. The word comes from Greek and means "substances foreign to life". In general, these are substances that are foreign to natural ecosystems, including the body, and are usually produced chemically. These xenobiotics can have a negative, no or positive effect on our organism.Sulforaphaneis a xenobiotic with a positive effect on the body. This effect is caused by the activation of Nrf2. The molecule, which occurs naturally in broccoli and cabbage, therefore acts indirectly as a strong antioxidant. In cell cultures and in animal experiments, sulforaphane has been shown to have an inhibitory effect on certain tumor cells and to enhance the effect of certain chemotherapies. The xenobiotic is being intensively researched because of its promising effects.
Cheers to the relationship police
The idea of supporting radical scavengers and thus antioxidants in terms of quantity and activity therefore seems quite logical. We have learned that certain supporting substances are indeed found in everyday foods. But there is a caveat: the amount of wine we would have to drink to absorb a clinically adequate amount of resveratrol amounts to dozens of liters. Fortunately, it is possible to isolate these molecules and thus consume the necessary amounts.
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