So the biodiversity in the intestinal flora protects the health

HZI: Biodiversity of good gut bacteria keeps us healthy

The importance of the intestinal flora for our health has increasingly become the focus of research in recent years. Above all, the strengthening of the immune defense by healthy intestinal bacteria offers interesting starting points under medical aspects. How the beneficial intestinal bacteria strengthen the immune system has remained largely unclear. The short-chain fatty acid butyrate, which is formed by intestinal bacteria, seems to play a special role here.

"The short-chain fatty acid butyrate is formed by intestinal bacteria and is the main energy source of the intestinal cells," reports the Helmholtz Center for Infection Research (HZI). Butyrate is an important factor in the health of humans, because it strengthens the intestinal epithelium and stabilizes the local immune system. In a recent study, researchers at the HZI have now developed a way to identify butyrate-forming bacterial groups in the intestinal microbiome. Their results have been published in the journal "mSystems".

In our intestinal flora in particular the butyrate-forming bacteria have beneficial effects on health. Scientists have now developed a method to specifically identify these bacteria. (Image: Alex / fotolia.com)

Butyrate crucial

"The researchers were able to show that on average, there are over 20 different butyrate-forming species in the gut of a person who can adapt to different environmental conditions in order to preserve human health as a whole," says the HZI. According to the researchers, the special short-chain fatty acid butyrate has far-reaching effects on human health. Chronic shortage of butyrate is associated with conditions such as type 2 diabetes, obesity and cardiovascular disease.

Which bacteria can produce butyrate?

The butyrate-producing bacteria are therefore of particular interest in current microbiome research, which has so far focused primarily on studies of individual bacterial species. However, the HZI scientists have now, according to their own statements, succeeded in developing a "workflow" that allows to uncover the large variety of intestinal bacteria that can produce butyrate and thus explore the entire butyrate-producing potential of complex bacterial communities. "

Intestinal flora opens up additional energy sources

The fiber, which is absorbed by the food, is broken down in the large intestine by the local bacterial community, among others, into short-chain fatty acids, explain the scientists. This opens up the intestinal flora to the human body an energy source that he is unable to use with his own resources. The fatty acids formed cover more than 70 percent of the energy metabolism of the intestinal epithelial cells, the HZI researchers continue. Butyrate, the salt of butyric acid, represents the most important source of energy for the intestinal cells.

Understand biodiversity of intestinal bacteria

According to the scientists, butyrate produced by microorganisms is essential for maintaining good health. In addition to the nutrition of the intestinal cells, it also controls the immunological defenses of the intestine and also influences various metabolic pathways throughout the body, for example in the liver or in the brain. Given their health benefits, there is great medical interest in identifying the butyrate-forming bacterial communities. "The researchers want to better understand their biodiversity and ecology in the various areas of the intestine," reports the HZI.

Butyrate deficiency increases the risk of disease

According to Dr. Marius Vital, a scientist in the HZI working group on "Microbial Interactions and Processes," has linked a chronic shortage of butyrate in various previous studies "with the onset of diseases such as type 2 diabetes, obesity, or cardiovascular disease." Also increase in chronic butyrate deficiency, the risk of infectious diseases in the intestine.

Consider the efficiency of the entire bacterial community

According to the expert, the butyrate-producing community in the intestine consists of many bacterial strains and forms a biochemically diverse group. Several types of bacteria are involved, "especially different Firmicutes and some Bacteriodetes." Often, however, "neglected the functional capacity of the entire bacterial community in the intestine, which complicates a comprehensive analysis of butyrate."

Identify functional bacterial species

The scientists have now developed a method to quantify and identify in detail the composition of the butyrate formers and to analyze their biochemical and taxonomic diversity, reports the HZI. Using information from several publicly available datasets from patients with a variety of conditions, such as diabetes, obesity, or cirrhosis, researchers were able to identify key environmental features of the functional bacterial community and gained important information on their role in human health.

On average, 20 butyrate-forming bacterial species in the intestinal flora

According to some researchers, every human being has an average of over 20 bacterial species in the intestinal flora that are capable of producing butyrate. The research has shown that "many bacteria produce fatty acids, which are so important to us," emphasizes Dr. med. Vital. The large biodiversity of butyrate-forming bacteria helps to maintain a functional stability of the intestinal microbiome in everyday life and also to reduce gross disorders such as antibiotic treatment.

The diet significantly affects the intestinal flora

According to the researchers, the diet also has an influence on the presence of butyrate-forming bacteria. Thus, a higher presence of the bacteria in plant-based diet show than excessive consumption of meat-containing foods. Also, the evaluation of the data confirmed, "that a lack of butyrate-forming bacteria with various common diseases such as diabetes, atherosclerosis or obesity is related, so the message from the HZI. The current findings could help to develop personalized drugs to suppress a so-called functional dysbiosis (deficiency of the health-promoting function, which emanates the various types of bacteria) and thus reduce the occurrence of diseases, the researchers hope. (Fp)