CNRS France: Through the study of the roundworm, Caenorhabditis elegans,
the team led by Hugo Aguilaniu has discovered a hormone that enhances
longevity and reduces fertility, thus reproducing the effects of an
extreme diet. The scientists, based at the Laboratoire de Biologie
Moléculaire de la Cellule (CNRS/ENS de Lyon/ Université Claude Bernard
Lyon 1), now intend to explore its mode of action in the hope of finding
new ways to combat age-related diseases. Their work is published on 11
September in Nature Communications.
Eating less prolongs the lifespan of a large number of species, from yeasts to primates to spiders and cats.
It is also known that drastic calorie restriction reduces the incidence of age-related conditions (such as
cancers, neurodegenerative diseases and muscle loss). This has been demonstrated in rodents and large
monkeys, and it is likely that the same applies in humans.
However, such extreme diets (bordering on
malnutrition) are difficult to maintain, notably because of their side effects, which are both psychological
(irritability, impaired libido) and physiological (reduced fertility).
For health reasons, these diets are
therefore not recommended!
In the
C. elegans
roundworm, Hugo Aguilaniu and his team have identified a hormone that is produced in
response to dietary restriction. This hormone, called dafachronic acid, is required to extend lifespan and is
also involved in diet-related loss of fertility. This
discovery thus establishes a direct link between increased
lifespan and decreased reproductive capacity in the context of a low-calorie diet.
The researchers have also discovered the receptor through which dafachronic acid exerts its action in cell
nuclei. As the "conductor of the orchestra", its presence can activate a large number of genes. In this
"genetic symphony", some genes will induce a reduction
in fertility while others will slow down the ageing
process.
Hugo Aguilaniu now hopes to be able to dissociate these two types of response in order to artificially
trigger the hormone's protective effect against age-rela
ted diseases, without causing harmful side effects.
This may open the way towards therapeutic applications, as the hormone thus identified, and its receptor,
have close relatives in mammals and humans.
This work was partially funded by the French Medical Research Foundation.