Cellular and physiological activity in the body declines over time with age, resulting in a loss of tissue and organ function and the potential risk of major health conditions such as cancer or cardiovascular disease. What is less understood are age-related changes in the tissue microenvironment such as the blood vessels.
Blood vessels are an essential component in maintaining tissue function not only because they form vital transport routes around the body, but also because blood vessels engage in signalling with neighbouring cells within the tissues thereby governing their behaviour. For example, blood vessels provide nurturing niches for stem/progenitor cells and regulate their stemness and fate. Therefore, any vascular changes have the potential to reveal microenvironmental triggers impacting the aging process.
For the study which appears in Science Advances Anjali Kusumbe’s group examined 1000’s of confocal images across several murine and human organs. “The cellular aspects of ageing have been extensively studied and we understand how they affect tissue function. Our goal was to understand age-related changes to blood vessels, the vascular system, by comparing young and ageing tissues from several organs through 3D imaging.” said Anjali.
3D imaging showed the vascular microenvironments of the kidney, muscle, spleen, thymus, liver, lung, uterus, heart, bladder, brain, skin, and the gut. By comparing young and ageing tissues from several organs the study revealed a loss of vascular abundance and differentiation of pericytes into fibroblasts as the key features of ageing tissue. Pericytes are the cells lining the blood vessels and support vascular functions while fibroblasts are known drivers for disease conditions such as fibrosis and arthritis.