Telomeres are the protective caps of our chromosomes and play a central role in the aging process. Shorter telomeres are associated with chronic diseases and high stress levels can contribute to their shortening. A new study now shows that if telomeres change in their length, that change is also reflected in our brain structure. This association was identified by a team of scientists including Lara Puhlmann and Pascal Vrtička from the Max Planck Institute for Cognitive Brain Sciences in Leipzig together with Elissa Epel from the University of California and Tania Singer from the Social Neuroscience Lab in Berlin as part of Singer’s ReSource Project.

Telomeres are protective caps at the ends of chromosomes that become shorter with each cell division. If they become so short that the genes they protect could be damaged, the cell stops dividing and renewing. Consequently, the cell is increasingly unable to perform its functions. This mechanism is one of the ways in which we age.

Telomere length is therefore regarded as a marker for the biological age of a person—in contrast to their chronological age. For two people of the same chronological age, the person with shorter telomeres has an increased risk of developing age-related diseases such as Alzheimer’s or cancer, and even a shorter life expectancy.

Cells that become senescent irrevocably stop dividing under stress, spewing out a mix of inflammatory proteins that lead to chronic inflammation as more and more of the cells accumulate over time. Publishing in the September 24 edition of Cell Reports, researchers at the Buck Institute identified 44 specific senescence-associated proteins that are involved in blood clotting, marking the first time that cellular senescence has been associated with age-related blood clots.

“The incidence of venous thrombosis, which includes deep vein thrombosis and pulmonary embolism is extremely low until the age of 45, when it begins to rise rapidly. Over time it becomes a major risk factor for death. By 80, the condition affects five to six people per thousand individuals,” said Judith Campisi, PhD, Buck professor and senior co-author of the study. “Blood clots are also a serious side effect of chemotherapy, which sets off a cascade of senescence in those undergoing treatment. That’s why blood thinners, which carry their own risks, are often included in treatment protocols.”

Scientists in the Campisi lab and other labs around the world are working to develop senolytics, drugs which would clear senescent cells from the body, potentially providing treatment options for many age-related diseases that are either caused or linked to senescence. They include Alzheimer’s and Parkinson’s diseases, cardiovascular disease, osteoarthritis, macular degeneration, age-related cancers and sarcopenia, among others.