How is my intestine actually doing? This question is more present than ever, because the microbiome of our intestine is becoming more and more aware of us and is now considered responsible for many mechanisms in our body. There are many factors that determine whether we become ancient, and we probably have more influence on them than previously thought. The latest research indicates that the intestinal flora plays a significant role in how long we live and which diseases we will suffer from.
In this article, we will show you what the current state of research on the subject of the microbiome is, whether microbiome tests are even worthwhile and what short-chain fatty acids, such as butyrate, have to do with health.
What is the microbiome?
To get started, we need to briefly clarify what the microbiome actually is. Strictly speaking, we have different microbiomes. Wherever there are bacteria, viruses and fungi we can speak of a microbiome. These are e.g.b the gastrointestinal tract (especially the intestines), the skin, the mouth, the respiratory tract and the urogenital system.
In this article we will mainly focus on the intestinal microbiome, our intestinal flora.
The tasks of the microbiome
The human microbiome represents an inexhaustible field of research that produces new scientific discoveries every day. We learn more about the inhabitants of our intestinal flora, the gut-brain axis and how diseases can possibly be treated via the microbiome. Without the symbiosis between our bacteria and the body, we would most likely not be able to survive. The microbiome is e.g.b essential for the assimilation of certain nutrients from food. The human body alone does not have the full spectrum of enzymes necessary to break down every nutrient.
Waste products and gut feeling
The term microbiome is used synonymously with the intestinal flora and means the entirety of microorganisms that populate our intestines. What is often viewed as “waste” for the human organism, such as fiber, serves the intestinal flora as an essential source of nutrition. The microbial digestion of these substances is not only vital for the bacteria themselves, but also results in the production of metabolites that are of great benefit to human health, including secondary bile acids, vitamins, amino acid derivatives and short chain fatty acids.
In addition, there is a significant connection between the microbiome and the enteric nervous system – an extensive network of neurons that runs through the entire gastrointestinal tract. This is often described as the “second brain” or the physical manifestation of the “gut feeling.”
Did you know?
Sugar substitutes are suspected of playing a role in insulin resistance, a precursor to diabetes mellitus. It was originally hoped that the sugar substitutes could deliver the sweet taste without the negative effects of sugar. However, this does not appear to be the case. In this study the researchers were able to show that sweeteners can change the microbiome and thus contribute to the development of the disease.
Research on the microbiome
The field of research on the microbiome is still quite young. This is due, among other things, to the fact that many bacteria in our intestines are strict anaerobes. This means that if they come into contact with oxygen, they die almost immediately. To get around this problem, there are various ways that researchers have come up with. One of these is the Human Microbiome Project.
Human Microbiome Project (HMP) – the starting signal for research into the microbiome
The Human Microbiome Project (HMP) was a groundbreaking initiative aimed at understanding the complex microbial communities that populate the human body and exploring their role in health and disease. Launched in 2007 by the National Institutes of Health (NIH) in the United States, it was one of the first major research programs to systematically address the human microbiome.
Goals of the Human Microbiome Project
The main goal of the HMP was to create a reference database of the microbiota that inhabit different parts of the human body, including the intestine, mouth, skin and the urogenital tract. By using cutting-edge genomic technologies such as 16S rRNA sequencing and metagenomics, the project sought to catalog the genetic diversity of microbial communities and understand their functions, interactions and impact on human health.
Key findings
One of the key results of the HMP was the recognition that the human microbiome has enormous diversity and represents a significant genetic resource that is essential for human physiology. The project revealed that microorganisms are involved in many important biological processes, including:
- Digestion and metabolism of nutrients
- Development and function of the immune system
- Protection against pathogenic microorganisms
- Influence on brain function and behavior
In addition, the HMP showed that changes in the microbiome are linked to a variety of diseases, including inflammatory bowel disease, obesity, diabetes, cardiovascular disease and even psychiatric disorders such as depression
Did you know?
The colonization of the intestinal flora is a lifelong process that begins at birth and only ends with death. In a study published in “Nature Metabolism”, the intestinal flora of 9,000 people in an age group of 18 to 101 years were compared. The researchers found that not only people age, but also the microbiome of the intestine. In healthy subjects over 77 years of age, changes in the intestinal flora were found, in which rare bacterial species dominated and the usual microbiome pattern decreased. This uniqueness was absent in less healthy subjects.
Microbiome test – what options are there?
The HMP also gave rise to the desire for reliable microbiome tests. In the project, complete genome sequencing, also known as whole genome sequencing (WGS), was used for microbiome analysis. The advantage is that everything is analyzed and that is also one of the disadvantages. True to the saying, “Can't see the forest for the trees any more”, a WGS can offer too much information that we can't even classify as of today. Perhaps in the future it will be possible to better evaluate this wealth of information with the help of artificial intelligence.
Another disadvantage of complete genome sequencing is the high costs, both financially and in terms of workload. There are also other microbiome tests on the market:
Strain analysis of bacteria
Strain analysis of bacteria, often performed using 16S rRNA sequencing, focuses on the identification and quantification of specific bacterial species or strains in a sample. 16S rRNA gene sequencing targets a highly conserved region in the bacterial genome, allowing discrimination between different bacterial strains. Think of it like a barcode. Every bacterium has such a barcode (the 16S rRNA) and this barcode always varies slightly for each bacterial species. This allows researchers to distinguish between different types of bacteria.
Did you know?
A quick explanation of the terms. Bacteria are divided into families and phyla. The first part of the word represents the family name, e.g.b Bacillus and the second part of the name represents the strain, in this case Bacillus subtilis. Even if this name sounds more like a pathogen, Bacillus subtilis is extremely important for our health. It was even voted “Microbe of the Year 2023”. You can find out more about this exciting bacterium in our article on QBIOTIC.
More microbiome tests
In addition to those already mentioned, there are a few other tests. Shotgun metagenome sequencing and metaproteomics are still widespread. Compared to 16S rRNA gene sequencing, the former offers the advantage that other organisms, such as viruses or fungi, are also included. With metaproteomics you don't look at the genetics but rather at the proteins produced. This research field, also called proteomics , is one of the most exciting in the field of personalized medicine and longevity. In comparison to epigenetics, where the markers on the DNA are measured, proteomics looks at the proteins produced. The latest test from MoleQlar is based on this, with which you can find out your molecular profile. In collaboration with the renowned LMU Munich, we offer you a deeper insight into your molecular self.
Discover your proteome with MoleQlar's Molecular Profile test. Find out more now.
It's not just the genes
The research field on the microbiome is highly complex and is shaped by many influences. An interesting example is the bacterium Eggerthella lenta (E. lenta) DSM 2243, a bacterium that occurs in the human intestine. E lenta has an interesting interaction with the heart drug digoxin. Digoxin has been widely used to treat certain heart conditions such as heart failure and irregular heartbeat. It works by improving the efficiency of the heart muscle and regulating heart rate. It is now only rarely used to treat these diseases. One of the reasons was the difficulty of dosing the drug. Even small amounts of digoxin worked for some people, while others needed a much higher dose. A possible explanation is probably hidden in our intestines.
How the microbiome influences medications
Certain Strains of E. lenta are able to metabolize digoxin and inactivate it, reducing the effectiveness of the drug in the body. This microbial metabolism occurs through the enzyme cardiac glycoside reductase, which converts digoxin into a less active form. And here another factor comes into play to make the whole connection more complex. Colleen Cutcliffe, a molecular biologist, said on Peter Attia's podcast that it makes a difference whether E. lenta has one copy of the gene that codes for the enzyme, above five genes. People who have an E.lenta form with five genes for inactivating digoxin appear to respond significantly less well to the drug. If we can find out more about these interactions in the future, it will be a further step towards personalized medicine.
How to strengthen the microbiome?
Now that we have learned a lot about testing and the background to the microbiome, we will address the question of what we can do to build up the microbiome. to strengthen.
Before we delve deeper into the topic, we need to define a few terms: If you want to know more about the individual topics, you can simply click on the word and you will be taken to a detailed article:
- Probiotics: These are preparations that e.g.b contain living intestinal bacteria. Probiotics are often used to make the intestinal flora a little more species-rich again. to restore the balance between “good” and “bad” bacteria
- Prebiotics: Prebiotics are substances, mostly indigestible carbohydrates such as inulin, fructooligosaccharides (FOS) and galactooligosaccharides (GOS), which selectively increase the activity or promote the growth of health-promoting microorganisms in the intestine. You find them in your food as fiber and they serve as “food” for your intestinal bacteria
Did you know?
The German Nutrition Society (DGE) recommends a daily intake of at least 30 grams of fiber for adults. These substances can only be found in plant products, e.g.b in whole grain products, fruits and vegetables. A high fiber content in the food ensures that the bacteria in the intestine get enough nutrition. However, most people eat less than the recommended 30 grams per day.
- Symbiotics: Symbiotics are products or dietary supplements that contain a combination of probiotics and prebiotics . The idea behind this is that the prebiotics serve as a source of nutrients for the living microorganisms supplied with the probiotics, which can improve their survival, colonization and effectiveness in the intestinal tract.
- Postbiotics: Postbiotics are bioactive compounds produced by the metabolic activity of probiotic microorganisms in the intestine. These include short-chain fatty acids (such as butyrate, propionate and acetate), bacteriocins, enzymes, vitamins and other metabolites. These substances can have positive effects on the host, for example by supporting intestinal barrier function, having an anti-inflammatory effect and modulating the immune system.
You can strengthen your intestinal flora in all of these ways. The easiest thing is probably to adjust your diet by adding more fiber. If you are not currently consuming a lot of fiber per day, it is best to increase the amount slowly, otherwise you may experience bloating or gastrointestinal problems. You can find out more about the topic in our article on Building intestinal flora.
The butyrate metabolism - not only important for intestinal health
Butyrate metabolism refers to the biochemical process by which certain microorganisms in the human intestine ferment indigestible carbohydrates (particularly fiber), producing short-chain fatty acids (SCFAs) like producing butyrate. Butyrate is of particular interest because it has a variety of positive effects on our health, including promoting intestinal health, strengthening the intestinal barrier function, anti-inflammatory effects and potential protective mechanisms against metabolic diseases such as type 2 diabetes mellitus.
Butyrate production in the intestine
Butyrate production occurs through the Fermentation of fiber by anaerobic bacteria in the large intestine. These bacteria, which include genera such as Faecalibacterium, Eubacterium, Roseburia and Butyrivibrio, use fiber as an energy source and in the process produce SCFAs, including butyrate. Butyrate then serves as the main source of energy for the cells of the intestinal mucosa (colonocytes) and supports their health and function. By the way: The intestinal mucosa cells are the only cells in the body that can use butyrate as an energy source.
Did you know?
Perhaps you know the “miracle weight loss drug” Ozempic, also known as a weight loss injection. Actually, this is a drug against diabetes mellitus that mimics a hormone in the body. To be precise the GLP-1 (Glucagon-like Peptide-1). You can find out more about this in the article about Berberine. But back to the microbiome. The butyrate produced by the bacteria can stimulate the L cells in the intestine, which in turn produce the hormone GLP-1. Therefore, a diet rich in fiber can indirectly increase GLP-1 secretion by stimulating butyrate production and thus have positive effects on the glucose metabolism and appetite regulation.
Bioavailable berberine with chromium and zinc in the mineral complex Berbersome
The role of Bacillus subtilis
Bacillus subtilis, often cited as a probiotic bacterium, plays a slightly different role in the microbiome than the direct producers of butyrate. b subtilis is a gram-positive, soil-dwelling bacterium that can also be found in the human intestine. It is known for its ability to form robust endospores, allowing it to survive difficult environmental conditions. Although B. subtilis is not directly involved in the production of butyrate, it may still have indirect effects on butyrate metabolism and overall gut health:
- Promotion of healthy intestinal flora: B. subtilis can support the growth and activity of butyrate-producing bacteria in the gut by promoting microbial diversity and ecological balance.
- Stimulation of the immune system: B. subtilis can modulate the immune response and contribute to the integrity of the intestinal barrier, which may indirectly improve the environment for butyrate production.
- Competition with pathogenic microorganisms: Due to its antimicrobial properties, B. subtilis inhibit the growth of harmful bacteria, thereby supporting healthier intestinal flora, which in turn promotes butyrate production.
All of these properties have contributed to B.subtilis was named microbe of the year in 2023.
The microbiome and its role in longevity
The older we get, the more our microbiome loses diversity. In the worst case, a symbiosis becomes a Dysbiosis. The changes in the microbiome can be so severe that they have been included as one of the Hallmarks of Aging . These describe the molecular changes that occur with age. The hope is that if we can reverse these hallmarks, we can also stop aging.
Conclusion
“…a diseased intestine is the root of all evil…” Hippocrates already knew. An intact intestine is extremely important for our health and a long life. Understanding the molecular composition of the intestinal flora is a challenge that we must now meet. Our microbiome is a highly complex and exciting field of research. Thanks to newer methods of genetic analysis and proteomics, we have come one step closer to better understanding our intestinal flora. In the future, personalized medicine could also be linked to the microbiome.
