The intestine as a mirror of metabolic and cardiac disorders?

The Integrated Research and Treatment Center (IFB) AdiposityDiseases is starting to participate in the new international research project METACARDIS in 2013.

In it, a pool of 14 research centers and companies from France, Germany, England, Denmark, Sweden and Belgium are investigating how the human intestinal flora is connected with cardiac and metabolic disorders.

There aren't yet any deeper findings about the reciprocity between intestinal flora (microbiome) and cardiac or metabolic disorders (cardiometabolic disorders). But it has become clearer and clearer that the very high number of bacteria in our intestine has a bigger meaning for the cardiometabolic health than previously assumed. The European Union (1) is funding the multicentric research project METACARDIS (Meta­genomics and Integrative Systems Medicine of Cardiometabolic Diseases), which is scheduled to run for five years, with 12 million Euros. The total cost is about 20 million Euros.

Intestinal flora under the magnifying glass

By the means of clinical and experimental studies researchers in the METACARDIS project examine how the intestinal flora differs in study participants with different grades of metabolic and cardiac diseases. The IFB alone will deliver data of more than 600 test persons for this purpose. A special analysis of stool samples with a genetic determination of intestinal microbes and a measuring of many metabolic products is the core of the study. It provides a whole new possibility to describe the individual intestinal flora.

Generally the intestinal flora of humans with 400 to 500 different bacteria species is determined by human genes and germs with which each individual was confronted (2). Therefore there are interfamilial comparable interstinal floras. It is furthermore known that there are less kinds of intestinal bacteria in overweight patients than in normalweight people. The understanding of how intestinal flora is influenced by food or antibiotics (3) is also growing.

The number of bacteria in the human intestine is higher than the number of body cells (iStockphoto).

The METACARDIS researchers are getting to the bottom of those observations by checking the reciprocity between microbiome and its changes respectively and the development of diseases such as adiposity (morbid overweight), type 2 diabetes, arteriosclerosis, high blood pressure and cardiac insufficiency. Those very common diseases are etiologically connected. Diabetes for example often develops as a comorbidity adiposity. Heavy overweight often leads to the metabolic syndrome (high blood pressure, fat metabolism or blood sugar disorders), at first, which in turn eventually ends in diabetes and cardiovascular diseases.

Therapies with help of the intestinal flora?

It is therefore the goal of METACARDIS to identify the common pathogenic factors and courses of the mentioned diseases. In addition it should find out which characteristics of intestinal flora indicates an increased risk for falling sick and how it can be influenced therapeutically. Prof. Dr. Michael Stumvoll, scientific director of the IFB emphasizes the possibilities that METACARDIS is offering for patient treatment: "There are trendsetting ideas how to positively influence the microbiome. The food industry has long been thinking about probiotics, i.e. bacteria in food, and about probiotics e.g. in yogurt that specifically stimulate the bacteria growth. All new and surprisingly effective are approaches to transfer stool from healthy test persons to sick ones. With this method many factors of the metabolic syndrome have indeed significantly improved in the recipients after 12 weeks.“

It is however not yet cleared of what a "favorable" intestinal flora consists, with what bacteria stems and in which proportions. METACARDIS will contribute to answering those questions. Findings from clinical and basic research can lead to completely new treatments of adiposity and associated comorbidities such as insulin resistency, fatty liver, diabetes and arteriosclerosis in the future.

(1)  Supporting programme of the EU for the promotion of networked research in Europe
(2) Humans have a total of 10 to the 13th power of intestinal bacteria and "only" 10 to the11th power of body cells.
(3) Ingestion of antibiotics during sickness; the intestine also comes in contact with antibiotics by eating the meat of animals that have been treated with antibiotics.

Keywords: IFB-research