How is my gut doing? This question is more relevant than ever, because the microbiome of our gut is becoming more and more of a part of our consciousness and is now considered responsible for many mechanisms in our body. Whether we live to a ripe old age is determined by many factors, and we probably have more influence over them than previously thought. The latest research indicates that the intestinal flora plays a key role in how long we live and what diseases we will suffer from.
In this article, we will show you what the current state of research is on the subject of microbiome, whether microbiome tests are worthwhile at all and what short-chain fatty acids, such as butyrate, have to do with health.
What is the microbiome?
To start with, we need to briefly clarify what the microbiome actually is. Strictly speaking, we have different microbiomesWherever bacteria, viruses and fungi are found, we can speak of a microbiome. These include 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 is an inexhaustible field of research that produces new scientific discoveries every day. We are learning 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 essential for the assimilation of certain nutrients from food, for example. 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 intestinal flora and refers to the totality of microorganisms that colonize our intestines. What is often only seen as “waste” for the human organism, such as fiber, serves as an essential source of nutrition for the intestinal flora. 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.
There is also a significant connection between the microbiome and the enteric nervous system – an extensive network of neurons that runs throughout the gastrointestinal tract. This is often described as the “second brain” or the physical manifestation of “gut feeling”.
Did you know?
Sugar substitutes are suspected to play a role in insulin resistance, a precursor to diabetes mellitus, to play. Originally, it was hoped that the sugar substitutes could provide the sweet taste without the negative effects of sugar. However, this does not seem to be the case. In this study The researchers were able to show that sweeteners can alter 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 the researchers have come up with. One of them 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 inhabit 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 objective of the HMP was to create a reference database of the microbiota inhabiting different parts of the human body, including the gut, mouth, skin and urogenital tract. By using cutting-edge genomic technologies such as 16S rRNA sequencing and metagenomics, the project aimed to catalogue the genetic diversity of microbial communities and understand their functions, interactions and impact on human health.
Key findings
One of the key findings of the HMP was the realization that the human microbiome is extremely diverse and represents a significant genetic resource essential to 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
- influencing brain function and behavior
In addition, the HMP showed that changes in the microbiome are associated with 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 ends only with death. In a study published in the “Nature Metabolism“, the intestinal flora of 9000 people between the ages of 18 and 101 were compared. The researchers found that not only do people age, but also the microbiome of the intestine. In healthy subjects over 77 years of age, changes in the intestinal flora were observed, in which rare bacterial species dominated and the usual microbiome pattern decreased. In less healthy subjects, this uniqueness was missing.
Microbiome test – what options are there?
The HMP also gave rise to the desire for reliable microbiome tests. The project developed a complete genome sequencing, also known as Whole Genome Sequencing (WGS), is used.The advantage is that everything is analyzed and that is also one of the disadvantages. True to the saying, “can no longer see the forest for the trees“, a WGS can provide too much information that we cannot yet classify 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. But there are also other microbiome tests on the market:
strain analysis of bacteria
The strain analysis of bacteria, often performed using 16S rRNA sequencing, focuses on identifying and quantifying specific bacterial species or strains in a sample. 16S rRNA gene sequencing targets a highly conserved region in the bacterial genome, allowing differentiation between different bacterial strains. Imagine the whole thing like a barcode. Every bacterium has such a barcode (the 16S rRNA) and for each bacterial species this barcode always varies slightly. This allows researchers to distinguish between different types of bacteria.
Did you know?
Let me briefly explain the terms. Bacteria are divided into families and strainsThe first part of the word represents the family name, e.g. Bacillus and the second part of the name represents the tribe, in this case Bacillus subtilis. Even though this name sounds more like a pathogen, Bacillus subtilis is extremely important for our health. It has even been named “Microbe of the Year 2023You can find out more about this exciting bacterium in our article on QBIOTIC.
Further microbiome tests
In addition to those already mentioned, there are several other tests. The most common are the Shotgun metagenome sequencing and metaproteomics. The former offers the advantage over 16S rRNA gene sequencing that other organisms, such as viruses or fungi, are also included. Metaproteomics does not look at genetics, but the proteins producedThis field of research, also proteomics is one of the most exciting in the field of personalized medicine and longevity. Compared to epigenetics, where the markers on the DNA are measured, proteomics looks at the proteins produced. This is also the basis for the latest test from MoleQlar, 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. Learn more now.
It's not just the genes
The field of research 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 digoxinDigoxin was often used to treat certain heart conditions such as heart failure and cardiac arrhythmias. It works by improving the efficiency of the heart muscle and regulating the heart rate. It is now rarely used to treat these conditions. One of the reasons was that the drug was difficult to dose. For some people, even the smallest amounts of digoxin worked, while others needed a much higher dose. One possible explanation may be hidden in our intestines.
How the Microbiome Influences Drugs
Particular strains of E. lenta are able to metabolize digoxin and inactivate it, which reduces the drug's effectiveness in the body. This microbial metabolism is carried out by the enzyme cardiac glycoside reductase, which converts digoxin into a less active form. And here's another factor that comes into play to make the whole thing 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 or five genes. People who have a form of E.lenta with five genes for inactivating digoxin seem to respond much less well to the drug. If we can find out more about these interactions in the future, it will be another step towards personalized medicine.
How can you strengthen the microbiome?
Now that we have learned a lot about testing and the background of the microbiome, we will look at what we can do to build up or strengthen the microbiome.
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 contain, for example, live intestinal bacteria. Probiotics are often used to make the intestinal flora a little more diverse, or to restore the balance between "good" and "bad" bacteria.
- prebiotics: Prebiotics are substances, mostly indigestible carbohydrates such as Inulin, fructooligosaccharides (FOS) and galactooligosaccharides (GOS)that selectively promote the activity or growth of health-promoting microorganisms in the intestine. You find them in food as fiber and they serve as "food" for your intestinal bacteria
Did you know?
The The German Nutrition Society (DGE) recommends a daily intake of at least 30 grams of fiber for adultsThese substances are found exclusively in plant products, e.g. whole grain products, fruit and vegetables. A high fiber content in food ensures that the bacteria in the intestines get enough food. However, most people eat less than the recommended 30 grams per day.
- symbiotics: Symbiotics are products or food supplements that combination of probiotics and prebiotics contain.The idea behind it is that the prebiotics serve as a source of nutrients for the living microorganisms supplied with the probiotics, which can improve their survival, settlement 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 the 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 simplest thing is to adjust your diet to include more fiber. If you are not currently consuming a lot of fiber per day, then it is best to increase the amount slowly, otherwise you may experience bloating or gastrointestinal problems. You can find out more about this topic in our article on Build up intestinal flora.
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 (especially fiber) and thereby short-chain fatty acids (SCFAs) such as 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 intestineThese bacteria, which include genera such as Faecalibacterium, Eubacterium, Roseburia and Butyrivibrio, use the fiber as an energy source and produce SCFAs, including butyrate. Butyrate then serves as the main energy source for the cells of the intestinal mucosa (colonocytes), supporting their health and function. Incidentally, the intestinal mucosa cells are the only cells in the body that can use butyrate as an energy source.
Did you know?
Maybe you know the “miracle weight loss product” Ozempic, also known as a weight loss injection. Actually, it is a drug against diabetes mellitus, which imitates 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 berberineBut 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 may indirectly increase GLP-1 secretion by stimulating butyrate production and thus have positive effects on 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 gut. It is known for its ability to form robust endospores that allow 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 intestinal health:
- Promoting a 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 can inhibit the growth of harmful bacteria, thereby supporting healthier gut flora, which in turn promotes butyrate production.
All these properties have contributed to B.subtilis being named Microbe of the Year 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 dysbiosisThe changes in the microbiome can be so severe that they are considered one of the Hallmarks of Aging These describe the molecular changes that accompany aging. The hope is that if we can reverse these hallmarks, we can also stop aging.
Conclusion
“…a sick gut is the root of all evil…”, Hippocrates already knew. An intact gut is extremely important for our health and a long life. Understanding the molecular composition of the gut flora is a challenge that we must now face. Our Microbiome is a highly complex and exciting research field. Thanks to newer methods of genetic analysis and proteomics, we have come one step closer to better understanding our intestinal floraIn the future, personalized medicine could also involve the microbiome.
