Calorie Restriction Reduces the Number of Senescent T Cells in Older Mice

A sizable enough fraction of T cells of the adaptive immune system become senescent in old age to cause major issues. Senescent cells cease replication and secrete a mix of signals that cause harm in numerous different ways: rousing chronic inflammation; disrupting tissue maintenance and structure; encouraging other cells to become senescent. The cell dynamics of the immune system are quite different from those of tissues. Immune cells are provoked into replication by signals of damage or infection, and enough of that sort of stress over time will have large effects on the number of senescent immune cells. Somatic cells, such as T cells, can only replicate a set number of times before they reach the Hayflick limit and become senescent or self-destruct. The supply of new T cells is reduced with age, as the thymus, where thymocytes mature into T cells, atrophies. Reduced supply and increased replication stress due to damage, infection, and other disarray in the immune system leads to a growing number of senescent T cells. This is the case in aging, and also the case in conditions such as HIV infection, in which the thymus is damaged and the immune system put under great stress. In today's open access paper, researchers show that the practice of calorie restriction slows the accumulation of senescent T cells with age. Additionally, clearing these senescent T cells via a suitably targeted therapy also produces similar benefits. A range of other evidence has pointed ...
Source: Fight Aging! - Category: Research Authors: Tags: Medicine, Biotech, Research Source Type: blogs