The trick of wintering Darmflora saves through the cold winter

Strong overweight without diabetes - intestinal flora keeps fat bears healthy

Scientists were able to solve a mystery. The question was: how can it be that brown bears can put on a very strong fat pad in order to use this as an energy reserve for the winter without getting seriously ill? The researchers discovered special intestinal bacteria in their search.

Brown bears eat an enormous fat buffer as an energy reserve before hibernation, without this leading to overweight-related diseases such as arteriosclerosis or diabetes. Researchers have now asked why this is so. They came to the conclusion that intestinal bacteria play an important role. The findings could be used to treat obesity.

Fat brown bears without diabetes
In the summer, brown bears eat a thick fat pad, which serves as an energy reserve during hibernation. So far, however, it was not known why the animals do not suffer from obesity (obesity) and diabetes despite the strong weight gain. Swedish scientists have now investigated the role of the intestinal flora. By analyzing fecal samples "provided" by 16 wild brown bears, the researchers found that the species spectrum of the intestinal germs differs greatly in winter from that in summer. As the biologists and physicians report in the journal "Cell Reports", in parallel they compared characteristic blood (fat) values. In both areas, the scientists showed clear differences:

Intestinal flora. Picture: Alex - fotolia

Gut flora different in summer and winter
The team around Fredrik Bäckhed (University of Gothenburg) found that the respective blood values ​​differed greatly. In the summer, the diversity of intestinal bacteria was much greater. Above all, the intestinal flora contained far more of so-called gram-positive bacteria, which include actinobacteria, bacillus species and clostridia, reports the Austrian "Standard". In a second step, the researchers transplanted fecal samples from the summer and from the winter into the intestine germ-free reared mice, which promptly developed very different. Thus, the rodents with the summer bacteria became richer than the others, but showed a normal sugar metabolism and no signs of illness.

Grizzlies temporarily become diabetics
This makes it obvious to Fredrik Bäckhed that the intestinal flora is likely to be a more important regulator of energy metabolism and cold adaptation than previously thought. Another focus of research had been studies in which hibernation by grizzly bears was studied. These become diabetics in hibernation, as US scientists reported a few years ago. Although the animals are very thick in the autumn, but symptom-free. But only a few weeks later they are diabetic during hibernation. When waking up in spring, the animals are "healed" again. As the scientists wrote in the journal "Cell Metabolism", obesity does not necessarily lead to diabetes.

Approach to treatment of obesity
According to the Swedish researchers, the main aim is to identify a possible approach for the treatment of obesity from the bears. In previous scientific studies, a change in the intestinal flora compared to healthy persons was also found in obese people. In addition, studies have shown that the composition of intestinal bacteria differs in people in colder regions. Another human intestinal flora in the north is an advantage, as less heat is lost with higher weight. (Ad)