Our organs do not age at the same speed. But, certain parts of the body are not aging or very little.
There is a fascinating exception to the aging of the human body. While the majority of our organs and tissues show signs of wear with age, some keep an astonishing youth, even in the elderly. This long -known phenomenon, which is intrigued today, intrigues researchers and could open the way for new avenues for understanding aging.
This is for example the case of the cornea, this fine transparent membrane located at the front of the eye. “Unlike other tissues in the body, the cornea does not contain blood vessels, which reduces its exposure to aging processes linked to circulation (such as inflammation or accumulation of toxins). And for good reason, it is protected by the tear film and the eyelid, and is composed of cells that are constantly regenerated”, explains Professor Eric Boulanger, professor of medicine and aging biology. Even if it is not completely safe from certain pathologies, the cornea is one of the rare fabrics of the human body which change very little over time.
But the organ that most intrigues scientists is the liver. According to a study carried out by a team of German researchers from the University of Dresden, the liver would remain indefinitely young. Measuring on average 28 cm wide, 16 cm high, for 1.5 kg, it is the largest gland in the body. His eternal “youth” is explained by a rapid and constant renewal of his cells, throughout life. According to researchers, the average liver age is three years. “We have found that most hepatocytes were replaced within three years. Some hepatocytes (polyploid) can however stay in the liver for longer”specify scientists.
But, if the liver tissues are renewed frequently, how can we explain that you can have liver cancer? According to Olaf Bergmann, one of the authors of the study, the answer lies in other mechanisms of aging, such as chronic inflammation. “Although liver cells are renewed throughout life, this does not prevent the liver disease.” In other words, an organ can remain young in its structure, while being affected by inflammatory and/or environmental processes which promote the development of pathologies. This distinction between cellular youth and global health is essential to understand the limits of regeneration, and recalls that aging is a multifactorial phenomenon, far beyond the simple wear of tissues.
Thank you to Professor Eric Boulanger, professor of medicine and biology of aging and medical director of Temproform®.
