According to a team of researchers at the BatLab in UCD, bats may hold the key to the secret of disease-free ageing.
The team, led by Professor Emma Teeling, have been studying bats that live exceptionally long lives for creatures of their size: the species Myotis. Their research, published in Science Advances, has shown that as these bats age, their chromosomes are protected differently to those in humans and other animals.
Teeling is affectionately referred to as ‘the batlady,’ by students who’ve been in her classes, because of her enthusiasm and passion for bats and the genetic secrets they possess. Speaking to the University Observer, Teeling explains that she started working in UCD in 2005 “looking at the evolutionary history of bats,” which led to her being awarded ‘Young Researcher of the Year’ by Science Foundation Ireland (SFI). Following that award, SFI provided funding to study “which inherited mutations in genes leads to deafness and blindness in bats,” and the funding “allowed me [to] establish the BatLab here in UCD.”
In addition to living longer, bats seem to age healthier than humans, with cancer being very rare.
The BatLab’s big project over the past number of years has been to study ageing in bats. Bats are small and similar in size to a mouse with wings. Smaller animals tend to use energy faster and live shorter lives but some bat species live into their thirties and this, Teeling says, makes them “quite unusual, their ability to live long lives relative to their body size.” In addition to living longer, bats seem to age healthier than humans, with cancer being very rare.
The BatLab has discovered that Myotis bats’ DNA is protected differently than human DNA, and this may be the key to healthier ageing.
In order for living things to age, their cells must divide. Within the bodies of all living creatures, cells are continuously dividing, replacing older cells and enabling growth and repair. Every time a cell divides the genetic material needs to be copied. DNA is stored within chromosomes, and it is through replication of each chromosome that the DNA is copied.
However, chromosomal replication is not perfect, and each time a chromosome is copied, a little piece at either end can be lost. Evolution has allowed for such loss by providing a protective cap at the end of chromosomes called ‘telomeres.’ These are long stretches of unnecessary DNA, existing for the sole purpose of being removed during chromosomal replication to protect the DNA that is needed.
Each time the cell divides, the telomeres get a little bit shorter. Eventually, they get too short, and the cell can no longer divide. The cells either die or become inactive. This is all part of the ageing process in humans and results in age-related diseases such as cancer. The protective cap is added to chromosomes by an enzyme called telomerase in humans and other animals, but not in Myotis bats.
In cancer, cells divide, and telomeres become shortened and if they become too short the cells die. However, some cancers will result in increased levels of telomerase, which prevents telomere shortening, allowing cancerous cells to survive.
The BatLab discovered, through genetic analysis, that the telomeres of Myotis bats do not shorten as they age. As these bats do not have the enzyme telomerase, the scientists looked at the 225 genes associated with telomeres, and found two genes: ATM and SETX, which they suspect is responsible for telomere maintenance in bats.
To study the ageing of bats, Teeling explains that the lab had to start with catching baby bats, so that they would be able to tell their age, and capture the same bats every year.
To study the ageing of bats, Teeling explains that the lab had to start with catching baby bats, so that they would be able to tell their age, and capture the same bats every year. To do this, the lab teamed up with a group in France called Bretagne Vivante who have been studying Myotis bats in France for over 20 years.
The European Research Council awarded a grant in 2012 which would enable the BatLab and Bretagne Vivante to work together to develop bats as a model to study healthy ageing. Every summer since then, the BatLab have travelled to France where they capture bats as they’re flying out of their roosts at night.
The bats the BatLab studied roosted in old gothic churches and the team capture the bats when they fly out at dusk to hunt for food. “They would fly into the traps we set up and go down a plastic chute… and land in a soft box.” The team would then take that bats into the church “where they’re heated and weighed and measured. We take a little tiny bit of blood and a little bit of wing and we flash freeze that in liquid nitrogen.” The team can then analyse the genetic makeup of the bats.
The welfare of the bats is of the utmost importance. The team want the bat population to continue thriving and there are four vets involved within the programme. When the bats are captured Teeling says, “Everything has to be done to the best of their welfare.”
Understanding how bats maintain telomere length through gene activity could lead to potential gene-based therapies to maintain telomeres in cells, and protect the cells, tissues, and the entire body from the negative effects of ageing. Bats may not be the most beautiful creatures to a lot of people but hidden within their DNA could be the answers to protecting us against cancer. All in all, such research could lead to humans living, not longer, but healthier lives in their later years.