TRF1 Protein Loss Reduces Fat and Improves Metabolic Health in Mice Without Shortening Telomeres

BUFFALO, NY — October 27, 2025 — A new #research paper was #published in Volume 17, Issue 9 of Aging-US on September 17, 2025, titled “Depletion of the TRF1 telomere-binding protein leads to leaner mice with altered metabolic profiles.” In this study led by first author Jessica Louzame Ruano and corresponding author Maria A. Blasco from the Spanish National Cancer Centre (CNIO), researchers investigated the role of TRF1, a protein known for protecting telomeres, in regulating whole-body metabolism. The results suggest that TRF1 influences metabolic health through mechanisms unrelated to its known function in telomere maintenance. Obesity and metabolic disorders are major health concerns, especially as people age. To explore TRF1’s role beyond telomere protection, the research team studied both normal mice and genetically modified mice that lacked TRF1. Mice without TRF1 remained leaner over time, resisted fat accumulation, and showed healthier blood sugar and insulin levels compared to normal mice. Importantly, these benefits occurred without any detectable shortening of telomeres. The leaner body composition in TRF1-deficient mice was not due to reduced food intake or increased physical activity. Instead, the fat loss appeared to result from biological changes in how energy was processed and stored. Male mice without TRF1 gained less weight and had lower LDL cholesterol levels, even on a high-fat diet. Female mice showed milder effects, reflecting known sex-based differences in susceptibility to diet-induced obesity. This highlights the importance of including both sexes in metabolic research. “Major metabolic pathways related with energy production and regulation of metabolism homeostasis were also found downregulated in Trf1-deficient mice.” Gene expression analysis in the liver revealed shifts in several key pathways. Genes related to fat production, energy generation, and muscle growth were downregulated, while genes linked to inflammation and cholesterol synthesis were upregulated. The mice also showed signs of higher energy expenditure and a shift from using fat to protein as an energy source, possibly due to their reduced fat reserves. However, some older mice developed mild liver stress, including fibrosis and DNA damage, suggesting a possible long-term trade-off. Overall, this study expands the understanding of how telomere-related proteins influence more than just cellular aging. By identifying a connection between TRF1 and metabolism, the research opens new possibilities for targeting TRF1 or its pathways to address obesity and related conditions. Still, further studies are needed to clarify how TRF1 affects fat development and whether similar effects occur in humans. DOI - https://doi.org/10.18632/aging.206320 Corresponding author - Maria A. Blasco — mblasco@cnio.es Abstract video - https://www.youtube.com/watch?v=7AG3TBgDZIw Sign up for free Altmetric alerts about this article - https://aging.altmetric.com/details/email_updates?id=10.18632%2Faging.206320 Subscribe for free publication alerts from Aging - https://www.aging-us.com/subscribe-to-toc-alerts Keywords - aging, Trf1, metabolism, leaner, fat, telomeres To learn more about the journal, visit https://www.Aging-US.com​​ and connect with us on social media at: Facebook - https://www.facebook.com/AgingUS/ X - https://twitter.com/AgingJrnl Instagram - https://www.instagram.com/agingjrnl/ YouTube - https://www.youtube.com/@AgingJournal LinkedIn - https://www.linkedin.com/company/aging/ Bluesky - https://bsky.app/profile/aging-us.bsky.social Pinterest - https://www.pinterest.com/AgingUS/ Spotify - https://open.spotify.com/show/1X4HQQgegjReaf6Mozn6Mc MEDIA@IMPACTJOURNALS.COM