Remarkable Biological Phenomenon: The Secret Behind This Animal’s Immortality After Four Years

In the animal kingdom, aging is an inevitable constant, marked by a progressive degradation of cells and tissues. However, some species appear to defy this natural process, providing fertile ground for researchers seeking the secrets of longevity. Among them, the axolotl, a unique amphibian, reveals a fascinating enigma: after reaching a certain stage of development, its biological clock seems to stop.

A unique biological process

The study published on bioRxiv and relayed by Courrier international, led by Maximina Yun and Steve Horvath, focused on DNA methylation, a key biological indicator of aging in many species, including mammals and frogs .

Methylation is the process of adding methyl groups to DNA. This mechanism accumulates with age and affects cellular functioning. However, in axolotls, researchers have found that DNA methylation stabilizes after about four years. This phenomenon seems to mark a halt to biological aging.

In vertebrates, cellular aging is often due to the accumulation of DNA damage. Repair mechanisms deteriorate over time. However, in axolotls, this process seems to have stopped.

This discovery adds to studies on species with “negligible” aging, such as certain turtles or fish. However, the axolotl stands out for its unique ability to regenerate itself.

The implications of this phenomenon are multiple, particularly in the field of regenerative medicine, where the axolotl could offer clues on how to stop or slow down cellular aging in humans.

Regeneration and aging, two linked mechanisms?

The axolotl is already renowned for its ability to regenerate parts of its body. When it loses a limb, its cells become pluripotent again, that is, capable of transforming into any type of cell to rebuild tissues.

This mechanism relies on a low level of DNA methylation, which allows cells to “reset”. This peculiarity could be one of the reasons why axolotls no longer age after a certain age.

Researchers put forward the hypothesis that this permanent regeneration prevents the accumulation of cellular damage linked to aging. Thus, the DNA of axolotls would retain a certain plasticity, allowing the cells to remain young.

Maximina Yun also suggested that this cellular flexibility could counter aging by maintaining a capacity for regeneration throughout the animal's life.

This discovery also raises questions about the limits of axolotl biology: their death remains a mystery. Scientists still do not know the precise causes of their death, which further fuels research into their exceptional longevity.

Scientific perspectives and limits of current knowledge

Stopping aging in axolotls could lead to important breakthroughs in understanding longevity. DNA methylation, often linked to aging in many species, seems to be able to be stopped or stabilized in them.

This phenomenon remains an enigma. Still, researchers hope this discovery will pave the way for new studies on human regeneration and aging.

However, this study, while fascinating, raises more questions. For example, the precise mechanisms allowing the axolotl to suspend its aging remain unclear. In addition, the exact cause of their death remains unknown, which further adds to the mystery of their biology.

Axolotls therefore continue to captivate the scientific community, and this new discovery could well mark the beginning of an era where the study of aging will involve the in-depth analysis of these unique amphibians.