How intestinal bacteria can affect your blood sugar and lipid levels

April 10, 2018, Kumamoto University
Comparison of sugar and lipid concentration fluctuations in blood in a dysbiosis mouse model and non-antibiotic administered mice. Both sugar and lipid concentrations decreased in mice that received antibiotics only. Credit: Professor Sumio Ohtsuki

Intestinal bacteria have attracted recent attention since they were discovered to influence various physiological functions and diseases in humans. Researchers from Kumamoto University in Japan analyzing the influence of changes in intestinal bacteria on sugar and lipid metabolism have found that secondary bile acids produced by the bacteria can influence blood glucose and lipid concentrations as well as parts of their molecular mechanisms. This result is expected to lead to the treatment of metabolic diseases such as diabetes and dyslipidemia by targeting intestinal bacteria that produce secondary bile acid.

More than 100 trillion from an estimated 1,000 different species inhabit our intestines. It has been reported that the profiles of intestinal bacteria in obese and non-obese people tend to be different and involved with the health of the host. The bacteria may affect energy consumption and fat accumulation of host body. In addition, it is known that these bacteria are also associated with lifestyle diseases such as type 2 diabetes, nervous diseases such as autism, and such as colon cancer.

One factor that alters intestinal bacteria is the administration of antimicrobials. It is becoming clear that these drugs cause dysbiosis in the qualitative and quantitative balance of bacterial populations in the intestine and have various effects on vital functions. For example, hypoglycemia is a serious, but rare, side effect of antibiotics. In fact, some antibiotics, such as gatifloxacin, have been discontinued due to their side effects. Furthermore, taking antibiotics in infancy or childhood has been reported to accelerate weight gain.

Previous research has shown that dysbiosis due to antibiotic administration influences protein expression levels in the liver, an organ responsible for sugar and . Thus, researchers at Kumamoto University decided to clarify the influence of antibiotic-caused dysbiosis on sugar and metabolism and the mechanism thereof.

As the production of secondary bile acid decreased, proteins involved in glycogen metabolism and the biosynthesis of bile acid and cholesterol changed. As a result, the concentrations of sugars and lipids in the blood decreased. Credit: Professor Sumio Ohtsuki

A dysbiosis mouse model was prepared by administering antibiotics for 5 days. Compared to non-antibiotic treated mice, the levels and lipid (triglyceride) concentrations in the experimental model decreased to 64% and 43% respectively. To assess the mechanisms related to these reductions, researchers focused on secondary bile acids. These acids are metabolites produced by intestinal bacteria that control the liver functions involved in sugar and lipid metabolism.

In the experimental mouse model, intestinal bacteria producing secondary bile acids decreased. Additionally, the concentrations of secondary bile acids (lithocholic and deoxycholic acid) in the mouse liver were reduced to 20% and 0.6% respectively compared to non-antibiotic treated mice. When secondary bile acid is supplemented at the same time as antibiotic administration, blood glucose and blood triglyceride levels recovered. This result indicates that the secondary bile acid produced by intestinal bacteria affects sugar and lipid metabolism of the host.

Next, the researchers used quantitative proteomics to comprehensively analyze the amount of proteins to assess how secondary bile acids produced by influence liver sugar and lipid metabolism. In the livers of the dysbiosis mouse model, the expression levels of proteins involved in glycogen (storage of ) and in the biosynthesis of cholesterol and bile acids were found to have changed. Moreover, the change was restored through supplementation of secondary bile acids.

"Our research shows that enterobacteria and the secondary bile acids that they produce may be involved in the change of concentration of sugars and lipids in living bodies," said Kumamoto University Professor Sumio Ohtsuki, leader of the study. "It is expected that these bacteria will be a future target for the prevention or treatment of such as diabetes or dyslipidemia."

This research result was posted online in the journal Scientific Reports on 19 January 2018.

Explore further: Antibiotics pave way for C. diff infections by killing bile acid-altering bacteria

More information: Takuya Kuno et al, Reduction in hepatic secondary bile acids caused by short-term antibiotic-induced dysbiosis decreases mouse serum glucose and triglyceride levels, Scientific Reports (2018). DOI: 10.1038/s41598-018-19545-1

Related Stories

Antibiotics pave way for C. diff infections by killing bile acid-altering bacteria

January 6, 2016
New research from North Carolina State University and the University of Michigan finds that bile acids which are altered by bacteria normally living in the large intestine inhibit the growth of Clostridium difficile, or C. ...

Chronic liver inflammation linked to Western diet

July 12, 2017
A new study in The American Journal of Pathology reports that mice fed a Western diet, which is high in fat and sugar, resulted in hepatic inflammation, especially in males. Moreover, liver inflammation was most pronounced ...

Gut microbiota regulates bile acid metabolism

April 19, 2012
A new study presented today at the International Liver Congress 2012 demonstrates that the gut microbiota has a profound systemic effect on bile acid metabolism.

Bile acids fire up fat burning

January 16, 2018
Obesity arises from an imbalance between energy intake and energy expenditure. As a result, current treatments try to decrease calorie intake and/or increase energy expenditure.

New discoveries linking gut bacteria with cholesterol metabolism give hope for the future

February 18, 2013
(Medical Xpress)—Researchers at the Sahlgrenska Academy, University of Gothenburg, Sweden, show that cholesterol metabolism is regulated by bacteria in the small intestine. These findings may be important for the development ...

How important is the gut microbiome? It may depend on your genetics

November 7, 2016
Our gut microbiomes—the bacteria that live in our digestive tract—play major roles in our health. Scientists around the world are studying therapies that manipulate the microbiome, including probiotics (such as live bacterial ...

Recommended for you

The complicated biology of garlic

April 26, 2018
Researchers today generally agree that eating garlic, used for thousands of years to treat human disease, can reduce the risk of developing certain kinds of cancers, cardiovascular disease, and type 2 diabetes. Nevertheless, ...

Noninvasive brain tumor biopsy on the horizon

April 26, 2018
Taking a biopsy of a brain tumor is a complicated and invasive surgical process, but a team of researchers at Washington University in St. Louis is developing a way that allows them to detect tumor biomarkers through a simple ...

Lab-on-a-chip delivers critical immunity data for vulnerable populations

April 25, 2018
For millions of displaced people around the world—many of them refugees, living in temporary shelters under crowded conditions—an outbreak of disease is devastating. Each year, the measles virus kills more than 134,000 ...

Want new medicines? You need fundamental research

April 25, 2018
Would we be wise to prioritize "shovel-ready" science over curiosity-driven, fundamental research programs? Would that set the stage for the discovery of more new medicines over the long term?

Implantable islet cells come with their own oxygen supply

April 25, 2018
Since the 1960s, researchers have been interested in the possibility of treating type 1 diabetes by transplanting islet cells—the pancreatic cells that are responsible for producing insulin when blood glucose concentration ...

'Incompatible' donor stem cells cure adult sickle cell patients

April 25, 2018
Doctors at the University of Illinois Hospital have cured seven adult patients of sickle cell disease, an inherited blood disorder primarily affecting the black community, using stem cells from donors previously thought to ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.