Do bats have the "elixir of life"?

Bats have a significantly longer lifespan than other animals. the same size: making comparisons with humans we can say that only 19 species are longer-lived than humans and of these 18 are bats.

The other is the East African naked mole rat, Heterocephalus glaber, an underground animal with an amazing resistance to pain, which, like bats, adds a low risk of tumors to longevity and, like bats, is an important experimental model for study in this field.

Researchers study the immune systems of the only flying mammals to discover the secret that makes them long-lived, resistant to cancer and invulnerable to many infections.

In addition to being the only mammals to have acquired the ability to actively fly during the course of their evolution, bats also have the characteristic of being extraordinarily resistant to infection. But we know very little about the reasons why they enjoy such good health. Discovering whether behind this well-being there is a biological secret that can be exploited in medicine, therefore, could also represent a turning point for the prevention and treatment of many human diseases.

A new line of research on bats

For this reason, for some time now, both public and private research centers have been dedicated to the study of bats and, in particular, their immune system. With the pandemic, then, interest in them has grown even more, on the well-founded hypothesis that, by As with the first SARS virus, SARS-CoV-2 was also selected from among these animals. in the darkness of a cave in South China or Southeast Asia.

The public financing of this line of investigation, both from China and the United States, grew in 2021. The conferences until a few years ago reserved for a few enthusiasts saw the participation of researchers grow. In just three years, the number of references to flying mammals in immunology articles more than tripled.

From the study of bats drugs against inflammation.

Someone even begins to look at the possibility of a business. One of them is Phil Ferro, who worked in federal institutions his entire life and was for a time responsible for countering biological threats under the National Security Council at the White House. He believes in it so much that he has managed to convince several investors to finance the launch of a new start-up, Massachusetts-based Paratus Science, with $100 million in venture capital: the company's goal is to study the very particular biology . of bats for develop drugs against inflammation, a process now known to cut across many of the major diseases of our time, from autoimmune diseases to cancer, from metabolic disorders to cardiovascular disease and aging.

The first results

The field of research is limitless and requires different approaches because, for now, very little is known about the immune system of bats. From genome analysis, for example, it has been discovered that an extraordinary number of genetic fragments of viruses have been inserted into the DNA of some species of these animals over the millennia:Could this provide a kind of "congenital vaccination"? Bat genes also appear to contain the instructions for making "antivirals." natural»: Molecules that interfere with viral replication or prevent the particles from leaving the cell.

Another peculiarity of some bat species is the high basal level of interferon, a natural and non-specific product also produced by other mammals in response to infection, which, however, here seems to remain at a high level even in the absence of an infectious threat. This mediator in bats, unlike in humans, does not induce a strong inflammatory process.. Precisely, among the secrets of the resistance of these animals to infection seems to be precisely the ability to modulate the response without those intense reactions that sometimes do more damage to the organism than viruses and bacteria.

But to understand how these nocturnal animals can harbor terrible viruses without being harmed, and whether this depends on a possibly reproducible mechanism common to all bats and all viruses, we need to focus our attention on the complexity of the immune system of these very particular ones. mammals, even in response to different infectious agents. We need to study them alive.

The difficulty of cultivating colonies.

For this reason, some researchers have faced the risks and logistical difficulties of capturing them, trying to breed them in research centers. Not an easy task, as bats require favorable environments, have longer pregnancies and reproduce much less than common rodents used in the laboratory. Of the 1450 known species, so far only a few have managed to breed in captivity.: they are mostly fruit bats, like the Jamaicans studied in Colorado or the Egyptians cultivated on the island of Riems, in Germany, in one of the excellence in the study of the most dangerous viral diseases, with level 4 biosafety laboratories (BSL -4).

Nothing to do instead for the "horseshoes", as bats are called Rhinopolus, those where the first SARS virus is believed to have selected and where many specimens genetically related to SARS-CoV-2 have been found. So far no one has yet managed to create a colony that reproduces in captivity.

Understand your resistance to viruses.

In Asia, the largest bat colony is at the affiliated center of the Duke – National University of Singapore (Duke – NUS) Medical School, which you can count around 140 bats of the species Eonycteris spelaea (or Morning bat), fruit of the mating including some twenty specimens collected around Singapore between 2015 and 2016. By observing them, scientists try to understand the reasons for their longevity, their resistance to viruses, and the metabolism that allows them to fly.

The danger that comes from the caves, the bats

Meanwhile, fundamental research on the viruses inside bats continues, about the relationships between their evolutionary lines and about the mechanisms by which bats release infectious agents into the environment that are harmless to them, fundamental elements for the prevention of new emergencies.

In fact, we cannot forget that some of deadliest viruses that humanity has known have arrived precisely through contact with bats: from rabies to Ebola, from Hendra and Nipah to the coronavirus responsible for the first SARS, which at the beginning of the century caused hundreds of deaths.

Special guarded bats

Since then, as I mentioned here, bats have been observed in a special way, for among the many families of the order Chiroptera that groups them, thousands of coronaviruses circulate, many of which can be transmitted to humans. The effort has intensified in the quest to solve the mystery of the virus's origin: finding the animal that as an intermediate host likely carried the virus to the Huanan fish market would end a dispute in which political reasons have too often intervened. . prevails over those of science.

Animals to reevaluate

Until now, most of the research done on bats has focused on the risks they can pose, and this approach has helped fuel the fear and disgust they generate in many people. However, bats are essential to ecosystems, and not just because they protect us from pesky mosquitoes: The US Department of Fish and Wildlife has calculated that, thanks to insect-eating bats, crop damage and pesticide use worth more than $3 billion a year, only in the United States. If they also gave us the weapon to better resist the attacks of viruses and age, perhaps we would learn to appreciate them even more.