Specific microbiota identified which prevents obesity.
Obesity and its associated illness type 2 diabetes (T2D) have reached epidemic proportions. Increased food intake and lack of exercise are two main contributing factors, with past research firmly establishing an important role of gut microbiota in metabolic disorders. However, the exact mechanism linking gut microbiota to obesity is yet to be identified. Now, a study from researchers at the University of Utah Health identifies a specific class of bacteria from the gut which prevents mice from becoming obese. The team state the bacteria, called Clostridia, may similarly control weight in people. The study is published in the journal Science.
Previous studies show that the gut microbiota plays a major role in the development of food absorption and low grade inflammation, two key processes in obesity and diabetes. Recent studies from the group demonstrate that one role of the immune system is to maintain balance among the diverse array of bacteria in the gut, and that impairing the body’s defences can cause certain bacterial species to dominate over others, negatively impacting health. The current study shows that Clostridia prevents weight gain by blocking the intestine’s ability to absorb fat.
The current study utilises mice which are experimentally treated so that Clostridia is the only bacteria living in their gut, and mice treated to have an impaired immune system. Results show that the Clostridia-only mice were leaner with less fat than mice that had no microbiome at all. Data findings show Clostridia-only mice also had lower levels of the CD36 gene, which regulates the body’s uptake of fatty acids.
Results show that even when fed a healthy diet, the immune-compromised mice become obese, and giving Clostridia back to these animals allowed them to stay slim. The lab explain that the obesity observed in immune-compromised mice stemmed from the failure of the body’s defense system to appropriately recognize bacteria. They go on to add these mice produced fewer of the antibodies which made the gut less hospitable for Clostridia, leading to more fat absorption and excessive weight gain; over time, these mice also developed signs of type 2 diabetes.
The team surmise they have identified the specific microbiota which prevents obesity in mice. For the future, the researchers state the next step is to isolate the metabolites of the Clostridia microbiota and further characterize how they work to potentially treat obesity, type 2 diabetes, and other related metabolic disorders.
Source: University of Utah Health