Epigenetics is one of the most exciting fields of research. While it was previously thought that everything was in the genes, Today we know that only about 20% is directly inherited and the remaining 80% of our lifespan is determined by epigenetic changes.
The average adult consists of an immense number of approximately 100,000,000,000,000 cells. With only a few exceptions, such as mature red blood cells, all of these cells have a nucleus containing the human genome. We already know this term from the first Hallmark of Aging – the genomic instability. The genome is a term that, in simple terms, describes the entirety of an individual's heritable information. This is information for the production of proteins that determine and change the body's appearance.
So what does epigenetics do? Put simply, epigenetics determines which information is read and which is notHere we show you what effects epigenetics can have and what epigenetic changes have to do with age.
What does epigenetics do?
Every cell contains the same genetic information. How is it that some cells become muscle cells and others skin cells? The answer lies hidden in the cell nucleus.
We humans not only have a genome, but also an epigenome. The epigenome is a collection of chemical changes in DNA that essentially functions like a switchMany genes have such a switch. When the switch is ON, the gene is "expressed," meaning the blueprint is implemented, producing the desired protein. When the gene is switched off, it is considered silent, and no protein is produced.
Perhaps to better illustrate this, imagine your DNA is the text in a book. However, you never read the entire book because it's much too large; instead, you read only sections. To help you remember which sections you want to read, you've stuck little Post-It notes to the beginning and end of the passage. These Post-it notes are your epigenetic markers.
Chemically speaking, these are methylated sites on your DNA. They don't change your DNA itself, but rather determine which sections are read—and which aren't. To make things even more complicated: The text sections change throughout your life. Sometimes you read passages from one chapter and sometimes passages from the other chapter.. And it also depends on which cell you are looking at.
Did you know? Epigenetics is used to the biological age to eatUsing proteins in your cheek cells and modern algorithms, it is now possible to calculate quite accurately how old a body cell is compared to its chronological age. This is exactly the technology that is used in our Epiproteomics test for use.
The diversity of genes
Each gene contains the blueprint for one or more proteins. This is made possible by a process called "alternative splicingThis means that not all of the information on a gene is always read or used, but for some proteins only parts of it.
Accordingly, the number of proteins significantly exceeds the number of genes: If science today assumes 20,000 to 25,000 human genes out, the Number of proteins in humans is 80,000 to 400,000 More precise statements are currently difficult to make because research is still far from decoding all proteins.
A groundbreaking development by the company DeepMind will certainly help here. They have developed software with the help of a neural network called AlphaFold that can predict the 3D structure of proteins.
The role of epigenetic fixation
The role of epigenetic fixation
Epigenetics, also epigenetic fixation or epigenetic imprinting is the reason why different cell types develop from cells with the same conditionsThey all have the same genome, but different epigenomes that tell them which proteins need to be produced and what kind of cells they ultimately have to be.
In addition, epigenetics is partially hereditary, at least according to current research. Epigenetics research is still a relatively young field, but there are already some exciting results.
Did you know? After discovering that we can determine biological age with the help of epigenetic changes, the question remains how we can influence this. sport and Fast There are also some molecules that can help us reduce our biological age. At the forefront is Calcium alphaketoglutarate (Ca-AKG)In human studies, it has been shown to reduce biological age reduce by up to 7 years! In addition, it helps with muscle and bone building and supports our Mitochondria.
The combination with calcium ensures better AKG bioavailability in the organism.
Is epigenetics partly responsible for the obesity epidemic?
According to WHO figures, the rate of overweight people has tripled since 1975. Worldwide, 1.9 billion people were overweight in 2016 have been.
Obesity, especially severe obesity with high visceral fat content, represents a risk for many age-related diseases, such as diabetes mellitus and cardiovascular diseases.
But where does this sharp increase in obesity come from? Much of it is caused by poor eating habits and too little exercise. but epigenetics also has a hand in this.
Several animal experiments suggest that children of overweight parents inherit epigenetic patterns that predispose them to gain weight more quickly. The key point in the experiments was: It is often not the inherited genetics, but the inherited epigenetic pattern.
The good news, however, is that this pattern can be broken, for example, by replacing harmful epigenetic markers with new, more beneficial ones through proper nutrition. However, further research is needed to determine exactly how this might work in humans.
Epigenetic changes and aging
The epigenome, unlike the rigid DNA template of the genome, changes throughout life. Changes occur, for example, during physiological development, but environmental factors such as stress, disease, or nutrition also have an impact and not all changes are for the best.
Different epigenetic mechanisms cause these changes. This complexity is also the reason why we focus our attention on only one, but very important, epigenetic mechanism: DNA methylation.
This foreign term refers to the transfer of special chemical molecules, the methyl groups, to DNA. We'll omit the remaining chemical subtleties for the sake of clarity. As a result of the attachment of these chemical groups, the architecture of DNA changesWhereas stability suffers in the construction of a house, DNA can only be read in a modified form. To return to our analogy from the beginning. The DNA methylations are the colored post-it notes that tell you whether you want to read the text behind them or not.
Chemical reactions in the body, and thus also the transfer of methyl groups, usually require the presence of enzymes, as these create the optimal conditions. Accordingly, enzymes are also required here, the so-called DNA methyltransferases (Enzymes that transfer the methyl groups to DNA.) What does this rather complicated input have to do with aging?
Recent studies have shown that as time goes on, more and more methyl groups bind to the DNA. Epigenetic changes therefore increase with age – a fact that the Horvath Clock takes advantage of.
Progeria and DNA methylation
As a reminder: Progeria is a group of diseases with a dramatic (up to 10-fold) increase in the rate of aging. For example, it is possible for a ten-year-old girl with progeria to have a biological age of 70. You can find more details about progeria in the first Hallmark of Aging, which genomic instability.
In these people and also affected mice, researchers found in large parts similar methylation patterns as in healthy individuals of advanced ageA connection between DNA methylation and age is already present. Direct experimental evidence that lifespan can be extended by altering DNA methylation patterns is still pending.
DNA methylation
Epigenetic changes – outlook
Unlike DNA mutations, epigenetic changes are reversible. This opens up opportunities for the development of new longevity treatments. The totality of current scientific evidence suggests that understanding and manipulating the epigenome holds promise for improving age-related pathologies. This is inextricably linked to extending healthy lifespan.
However, if one considers the enormous complexity of epigenetics on the one hand and the current state of research on the other, one realizes that that efforts, especially with regard to humans, are still in their infancyThe coming years and decades will demonstrate the extent to which this can lead to tangible approaches for anti-aging and prevention. Ultimately, research is not a one-way street toward success—but it is certainly a one-way street toward understanding and education.
The next article in this series will cover the fourth hallmark of aging: Loss of proteostasis.
