September 19, 2023 by Françoise Fontanelle
Telomeres can influence aging and metabolism.
These small protective “caps” on chromosomes, which have been at the center of scientific research for about twenty years, are intriguing because their length may influence aging, cardiovascular disease, and metabolic diseases. Below we present the results of three recent studies that, beyond the importance of their results, shed light on how research is progressing.
Telomeres and Covid-19
At the end of the first half of 2020, a study carried out by the Telomeres laboratory of the DCAC Unit of the Inserm in Nancy, which was carried out with 38 people, aged 65 to 104, hospitalized in the geriatrics department of Nancy, 10 per Covid -19 and 20 more people for various reasons.
Their blood samples were used to measure the length and distribution of their telomeres, correlate this information with the patients’ lymphocyte counts, and then compare this data between the group of Covid-19 patients and the non-Covid-19 patients. The results demonstrated that “people infected with SARSCoV-2 and with short telomeres experience a delay in their immune response, leading to a deficiency in their blood reserve of T lymphocytes.”
A study carried out in children with Covid-19 confirmed this correlation, concluding that “since the average length of telomeres in children is greater than in adults, their replicative capacity to rapidly accelerate the production of T lymphocytes compensates even for a drastic loss of these.” . cells due to SARS-CoV-2 infection.”
A relevant avenue to continue examining the link between telomere length and lymphopenia (the drop in lymphocyte levels below the minimum threshold) in the case of Covid-19.
Telomeres, obesity and metabolic disorders in young children
From 2014 and 2015 to 2019, 73 children, aged between 2 and ten, who were overweight and obese, were followed at the Athens Medical School. First of all, the analysis of the length of their telomeres, carried out by Miguel Godinho Ferreira of Ircan (Institute for Research on Cancer and Aging of Nice) in collaboration with the National and Kapodistrian University of Athens and the “Aghia Sophia” Children’s Hospital ” from Athens. , showed the absence of “accelerated telomere length shortening” in these young patients during the follow-up period.
The study then found that “originally short telomeres were associated with more marked metabolic disorders.” It remains to be confirmed, through studies with a larger number of patients, whether telomere length can be considered a risk factor for early obesity and thus allow personalized care to be offered to children at risk.
Zebrafish telomeres
Zebrafish share 70% of their genes with humans. 84% of the genes related to human diseases have an equivalent in zebrafish. Their aging is similar to that of humans and is linked to age-related diseases, such as osteoarthritis, cachexia, neurodegenerative diseases and cancer.
This third study, the results of which were published in the journal Nature Aging on May 4, demonstrated that it is possible to extend the life expectancy of these small cyprinids. To do this, the scientists inserted a fragment of DNA into the zebrafish, allowing intestinal cells to produce the enzyme responsible for lengthening telomeres, telomerase. They then observed the slowing down of the deterioration of this organ and the aging of the entire organism of these fish.
This study opens great perspectives since “this phenomenon regenerates the fertility and general health of individuals throughout the normal aging process and increases life expectancy without the associated risk of developing cancer.” At the same time, researchers want to study pathologies associated with telomere shortening such as cancer, neurodegenerative, immune and gastrointestinal diseases.
