Washington State University (WSU) scientists have developed genetically modified mice that could significantly accelerate research into anti-aging treatments.

Globally, researchers are striving to unravel the biological mechanisms behind human lifespan extension at the cellular level. Aging is closely linked to the gradual shortening of telomeres—the protective ends of chromosomes that function like shoelace tips to prevent deterioration. As telomeres shorten over time, cells lose their ability to divide effectively, leading to aging and eventual cell death.

However, studying telomeres in human cells has proven to be challenging.

A breakthrough by a WSU research team, published in Nature Communications, offers a promising solution. Led by Professor Jiyue Zhu from the WSU College of Pharmacy and Pharmaceutical Sciences, the team has developed genetically engineered mice with telomeres that closely resemble those of humans. Unlike regular mice, which have telomeres up to 10 times longer than those in humans, these newly developed HuT (Humanized Telomere) mice provide a model for studying cellular aging in a way that mirrors human biology.

"This is the first mouse model with truly human-like telomeres because, in this model, telomerase is not expressed in adult tissues," Zhu explained. "Our research confirms that these mice exhibit human-like telomeres. Now, we aim to observe their aging process."

HuT mice are already being used to explore multiple research areas. Zhu’s team is studying how shortened telomeres influence the development of cancer and impact human lifespan. They are also investigating ways to prolong the health span—the period of life free from age-related diseases.

The findings have significant implications for developing future therapies. In the long term, this research may contribute to anti-aging treatments that help protect telomeres and extend lifespan. Zhu noted that many diseases originate at the cellular level, making it a critical target for drug development.

Telomerase, an enzyme that maintains telomeres, plays a key role in cancer research. Cancer cells require high levels of telomerase to sustain rapid cell division. "One of our goals is to reduce telomerase expression in cancer cells, and this remains an active area of study," Zhu said.

HuT mice also enable researchers to study the effects of aging more comprehensively. For example, Zhu’s collaborator, Christopher Davis from WSU’s Elson S. Floyd College of Medicine, is investigating how sleep deprivation and other life stressors impact telomere regulation and aging.

Zhu has been studying telomeres since the mid-1990s under Nobel Prize-winning scientists Elizabeth Blackburn and J. Michael Bishop, pioneers in telomere and cancer research. He joined WSU in 2014.

The development of HuT mice began a decade ago when researchers gained deeper insights into how telomere regulation differs between humans and animals. Previously, studying telomere-related aging processes was limited to isolated human cells in petri dishes. "This mouse model changes that," Zhu explained. "It allows us to study aging in a complete organism. Mice share similarities with humans in terms of organ structure, genetics, and overall biological makeup."

WSU aims to collaborate with other research teams by sharing the HuT mice, enabling broader studies on aging, longevity, and cancer. "There are thousands of scientists researching aging and cancer, and we believe this mouse model is a valuable tool for advancing these studies," Zhu said.

Zhu has secured $5 million in grants to further develop the model and investigate its implications for cancer. Funding sources include the National Institute on Aging, the National Institute of General Medical Sciences, and the U.S. Department of Defense, with the latter supporting research on telomere length’s impact on melanoma cells.