Some bats are voracious fruit eaters and have one of the sweetest diets of all. Feeding them exclusively one type of food should, in theory, prove detrimental to their health, but even though they consume terrifying amounts of carbohydrates each day, these animals do not suffer from diabetes.
For this reason, a team of scientists fromUniversity of California at San Francisco decided to delve into the secrets of their metabolism with the hope of finding something that could help doctors and biologists understand why we humans suffer when we have high blood sugar.
In theory, carbohydrates are the perfect biological fuel. They are easier to use than fat and, from a cellular point of view, are more efficient at producing energy and heat. However, our body, unlike other primates and the same fruit-eating bats, is not adapted to mass accumulation of large amounts of sugars, so much so that once we reach a certain level, our metabolism tries to get rid of them by sweating or urination. In the most severe cases, however, the human body is no longer able to regulate its concentrations, a condition that is a prelude to diabetes and its complications.
However, according to a study conducted by the company Nadav Ahituv, lead author of the bat article published on The nature of communicationOur problem would not be found so much at the metabolic level, but deeper, at the genetic level, in those complex mechanisms that regulate the concentration of sugars in the blood and inside the cells. In fact, bats have an actual genetic system that controls sugar levels that is much more sophisticated than our species, which is always based on on insulin.
“In diabetes, the human body is unable to produce or detect insulin, resulting in problems with sugar control,” said the scientist, who serves as director of the Human Genetics Institute at UCSF. – Kaloni, however, do not have these problems and have a genetic system that more effectively regulates the role of insulin in metabolism.”
Insulin is one of two peptide hormones produced by the pancreas that regulates the behavior of the body’s cells depending on the levels of sugar dissolved in the blood. Together with glucagon, it regulates the passage of sugars from the blood to the tissues that use them as energy source.
According to the scientists, it would be very nice if we could reproduce this genetic system in human cells, perhaps through genetic engineering, but at the moment we still need to better understand what processes allow bats to be different from us in the regulation and intake of sugars in order to create better therapies , which do not include many experiments on animals and human patients themselves.
Ahituv’s team is particularly focused on the evolution of organs that are very important for sugar control in all mammals. These are pancreas and kidneys, although the brain also plays a key role in the metabolism of a human or a bat. They found that the pancreas of a fruit-eating bat is quite different from the pancreas of insectivorous species or humans, as it contains a greater number of insulin- and glucagon-producing cells. They also have the cells of their entire organism some genetic modifications that help them process truly terrifying amounts of sugar coming from fruit.
According to some calculations, the studied bats, that is, the species Artibeus jamaicensis, they process so much sugar in a day that if this level were observed in our species, the person concerned would be immediately admitted to the hospital. Bat kidneys have also adapted to ensure the preservation of vital electrolytes, salts useful for the metabolic functioning of all tissues, while allowing sugars to end up in the urine if too much has been ingested and there is a risk of causing damage to various organs.
The researchers also highlight how the genetic expression of the insectivorous bat’s pancreatic cells, like in humans, has instead adapted to handle a diet based mostly on protein—which, remember, can be of animal or plant origin—and that’s because they have reduced number of cells that produce insulin and glucagon. However, cells in the liver and pancreas of all bats are generally more capable of sensing changes in sugar concentration. This allows it to respond better to high blood sugar levels, even if the individual is producing low amounts of the hormone.
This makes bats much more resilient and resilient to an all-sugar diet, and allows us to understand why our species is more at risk of diabetes. “Our bodies did not evolve to think that they only had to assimilate simple sugars. We have adapted to have a varied diet that contains more protein, which does not necessarily come from meat, the researchers conclude. – Bats, on the other hand, are like superheroes, each with their own incredible superpower. There are species capable of echolocation, others suck blood, and others constantly eat fruit without contracting diabetes.”
However, perhaps the main lesson to be learned from this research is not so much a possible solution to a disease that afflicts millions of people worldwide, but the understanding that each species has a specific adaptation to its natural diet and that we should start eating much healthier and foods with a low content of complex sugars.