Mice study supports omega-3 role in longevity

Polish and American scientists publishing in the journal Clinical Nutrition ​reported a positive correlation between n-3 FA and telomere length in fat-1 transgenic mice as compared to their wild-type siblings, indicating a slower rate of age-related telomere shortening in the former.

“This study, for the first time in a unique animal model free of dietary confounders, has demonstrated that increased levels of n-3 FA in tissues can reduce telomere attrition,” the researchers wrote. “The data presented indicate the possibility of using omega-3 fatty acids to reduce accelerated telomere attrition and, consequently, counteract premature aging and reduce the risk of age-related diseases.”

Telomere shortening and lifespan​

Telomeres, the structures composed of DNA sequences and proteins found at the end of chromosomes, shorten with age and are markers of biological aging. Inflammation and oxidative stress because of certain lifestyles can contribute to telomere shortening, ultimately impacting an individual’s healthspan. Cardiovascular diseases, cancer, diabetes and brain changes are connected to reduced telomere length. When it comes to older adults with cognitive impairment, the study identified research in which n-3 FA supplementation might reduce telomere shortening in those individuals.

According to the researchers, omega-3 fatty acids (n-3 FA) has an inverse relationship between baseline blood levels of n-3 FA and the degree of telomere shortening in leukocytes. However, more research is needed.

“Although a considerable number of cross-sectional and randomized human and rodent studies have demonstrated the beneficial effects of n-3 FA on telomere length, their results are not entirely consistent,” they wrote. “Human studies have examined diverse groups of people, given different amounts and types of n-3 FA, with various additional factors disturbing their diet…Therefore, there is a need for further well-controlled studies to determine the impact of n-3 FA on telomere length.”

Study details​

Fat-1 mice were used in the study because, unlike wild-type (WT) mice, these have elevated levels of n-3 FA in their tissues and organs plus a reduced n-6/n-3 FA ratio, which can improve blood lipids, the researchers noted. Whole blood samples were lysed to remove red blood cells from the mice, and proteins were then extracted. Nuclear DNA was removed from the blood, and LTL was measured using a real-time PCR-based method. The researchers compared FA levels, relative and absolute leukocyte telomere lengths and Western blot protein levels.

Fat-1 transgenic mice—which can convert omega-6 fatty acids (n-6 FA) to n-3 FA and have higher levels of endogenous n-3 FA in their tissues—were studied to determine the effects of n-3 FA on LTL at different ages, the scientists explained.

“The problem with many published studies on n-3 FA and telomere attrition is the fact that subjects are exposed to many other factors that could influence telomere biology,” they added. “In addition, the n-3 FA supplied in intervention studies is not pure but is a mixture of oils of marine or vegetable origin, which contain many confounding factors. Use of the transgenic fat-1 mouse model eliminates these sources of inaccuracy.” 

The researchers suggest that this is the first time that endogenous n-3 FA are associated with LTL in fat-1 mice, supporting the need for further research on the prevention of premature aging and diseases associated with telomere disruption.

“Short telomeres predict disease onset and slowing leukocytes aging could have significant effects by slowing the occurrence of age-related diseases,” the scientists wrote. “Our translational research broadens understanding of the n-3 FA therapeutic effects and should be consider for clinical studies and nutritional interventions.”

Source: Clinical Nutrition​
doi: 10.1016/j.clnu.2024.05.001​
“Elevated tissue status of omega-3 fatty acids protects against age-related telomere attrition in fat-1 transgenic mice”
Authors: Ogłuszka et al.