Epigenetics is one of the most exciting fields of research. Previously, we thought that everything was in our genes, We now 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 the immense number of about 100 000 000 000 000 cells. With only a few exceptions, such as mature red blood cells, all of these cells have a cell nucleus in which the human genome is located. We already know this term from the first Hallmark of Aging – the genomic instability. The genome is a term that simply describes the entirety of an individual's hereditary information. This is information for the production of proteins that determine and change the appearance of the body.
So what does epigenetics do? Put simply, epigenetics determines which information is read and which is not. We will show you here 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 can it be that some cells become muscle cells and others become 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 to the DNA that essentially functions like a switchMany genes have such a switch. If the switch is ON, the gene is "expressed", i.e. the blueprint is put into action and the desired protein is produced. If the gene is switched off (OFF), it is considered silent and no protein is produced.
Perhaps to illustrate this better. Imagine that your DNA is the text in a book. However, you never read the entire book because it is much too big, but only sections of it. So that you can remember which sections you want to read, you have stuck little Post-It notes to the beginning and end of the text passage. These Post-it notes are your epigenetic markers.
Chemically speaking, they are methylated sites on your DNA. They do not change your DNA itself, but rather determine which sections are read - and which are not. To make things even more complicated: The text sections change in your life. Sometimes passages from one chapter are read and sometimes passages from the other chapter. And it also depends on which cell you are looking at.
Did you know? Epigenetics is used about the biological age to eatUsing the surface characteristics of DNA and modern algorithms, it is now possible to calculate quite accurately how old a body cell is in comparison to its chronological age. This is exactly the same technology that is used in epiAge test for use.
Even more exciting is the relatively new method of measuring proteins in cells. With the help of the so-called proteomics We go one step further and measure not the DNA but the proteins produced. This allows a more modern and precise view of cell metabolism.
Do you know your biological age? The epiAge test has the answer.
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: Science today assumes 20,000 to 25,000 human genes out, the Number of proteins in humans at 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, which uses a neural network called AlphaFold to develop software that can predict the 3D structure of proteins, will certainly help here.
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 conditions. They 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 partly hereditary, at least according to current research. Research into epigenetics 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 as to how we can influence this. In addition to 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 was able to reduce biological age 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, poses a risk for many age-related diseases, such as diabetes mellitus and cardiovascular diseases.
But where does this sharp increase in obesity come from? A large part is caused by poor eating habits and too little exercise, but epigenetics also has a hand in this.
Several animal experiments lead to the conclusion that children of overweight parents inherit epigenetic patterns that predispose them to gain weight more quickly. The important point in the experiments was: It is often not the inherited genetics, but the inherited epigenetic pattern.
The good news here, however, is that this pattern can be broken by, for example, replacing the harmful epigenetic markers with new, more beneficial ones through the right diet. However, more research is needed to find out exactly how this can work in humans.
Epigenetic Changes and Aging
The epigenome, in contrast to the rigid DNA matrix of the genome, changes throughout life. Changes occur, for example, during physiological development, but environmental factors such as stress, illness or nutrition also have an impact and not all changes are for the best.
Different epigenetic mechanisms cause the changes. This complexity is also the reason why we focus our attention on just one, but very important, epigenetic mechanism: DNA methylation.
This foreign word refers to the transfer of special chemical molecules, the methyl groups, to the DNA. We will leave out the remaining chemical subtleties for the sake of clarity. As a result of the attachment of these chemical groups, the architecture of DNA changesWhereas the stability of a house suffers when it is built, the reading of proteins in DNA is only possible in a modified form. To go back 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 the DNA). What does this rather complicated input have to do with aging?
Recent studies have shown that over time more and more methyl groups bind to the DNAEpigenetic 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 dramatically increased rate of aging (up to 10 times). For example, it is possible for a ten-year-old girl with progeria to have a biological age of 70 years.You can find more details about progeria in the first Hallmark of Aging, the genomic instability.
In these people and also affected mice, researchers found in large parts similar methylation patterns as in healthy individuals in old ageA connection between DNA methylation and age is already present. Direct experimental evidence that the lifespan of the organism can be extended by changing the DNA methylation patterns is still pending.
DNA methylation
Epigenetic Changes – Outlook
In contrast to DNA mutations, epigenetic changes are reversible. This fact opens up opportunities for the development of new longevity treatments. The totality of current scientific evidence suggests that understanding and manipulating the epigenome holds great promise for improving age-related pathologies. This is inextricably linked to an extension of 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 show to what extent tangible starting points for anti-aging and prevention can be derived from this. Ultimately, research is not a one-way street to success - but definitely one towards understanding and education.
The next article in this series is about the fourth hallmark of aging: loss of proteostasis.
