Intestinal bacteria “talk” to horse cells to prolong energy output and improve their athletic performance

A typical endurance horse (Arabian breed) was presented for a gait test before the start of the race to check locomotor correctness. During the endurance competition (100-160 km), horses must undergo a veterinary examination at the end of each 20 to 40 km loop to check their recovery and ability to continue the race under good health conditions. Energy expenditure during the endurance race is very high, so it is an interesting model that shows the functional relationship between the microbiota profile and energy metabolism at the mitochondrial level. Credit: Eric Barrey

A study linking intestinal bacteria to more efficient energy production in horse cells paves the way for dietary supplements that improve their performance.

A horse’s gut microbiome communicates with its host by sending chemical signals to its cells, which results in helping the horse expand its energy, a new study published in Boundaries in molecular biosciences. This exciting discovery paves the way for dietary supplements that could improve a horse’s athletic performance.

“We were one of the first to show that certain types of equine gut bacteria produce chemical signals that interact with mitochondria in horse cells that regulate and generate energy,” says Eric Barrey, author of this study and Integrative Biology and Equine Genetics team leader at the National Research Institute of Agriculture, Food and Environment, France. “We believe that metabolites – small molecules created by the breakdown of larger molecules for food or growth – produced by these bacteria result in a delay in low blood sugar and inflammation in the cells, which in turn prolongs a horse’s athletic performance.”

Links to disease

Mitochondria, which can be briefly described as energy suppliers to cells, have been shown in recent studies to be interdependent with intestinal bacteria. In fact, many diseases associated with mitochondrial dysfunction in humans, such as Parkinson’s and Crohn’s disease, have been associated with changes in the gut microbiome in many previous studies.

“Studying horses is a good way to assess the link between intestinal bacteria and mitochondria, because the level of exercise, and thus mitochondrial function, that a horse performs during an endurance race is similar to that of marathon runners,” explains Dr. Nuria Mach, the first author of this paper, is also based at the National Research Institute for Agriculture, Food and the Environment, France.

She continues, “For this study, we obtained permission from veterinarians to take blood samples from 20 healthy horses of similar age and performance level, at the beginning and end of the International Endurance Competition in Fontainebleau, an eight-hour horse race in France. These samples provide information about chemical signals and the expression of certain genes, which is the procedure by which DNA it turns into instructions for making proteins or other molecules. To understand the composition of horse gut bacterial metabolites, we obtained faecal samples at the beginning of the race. “

The researchers found that certain bacteria in the gut are linked to gene expression by mitochondria in cells. Further, genes that were expressed or “involved” were associated with activities in the cell that helped it adapt to energy metabolism.

An evolutionary explanation

“It is interesting that mitochondria have a bacterial origin – it is believed that they created a symbiotic relationship with other components to create the first cell. This may explain why mitochondria have this line of communication with intestinal bacteria, ”says Barrey.

Mach concludes: “Improving our understanding of the communication between horses and the intestinal microbiome could help improve their individual performance, as well as the method by which they are trained and the intake of dietary composition. Manipulating the gut microbiota with probiotic supplements, as well as prebiotics, to feed good bacteria, could be a way to increase the health and balance of the microbiome and the horse, to better maintain endurance exercise. “

Reference: April 8, 2021, Boundaries in molecular biosciences.
DOI: 10.3389 / fmolb.2021.656204 /