As we get older, our bodies fill up with so-called senescent cells. These are cells that no longer divide and no longer support tissues. Instead, they emit substances that can be harmful, such as inflammatory substances. These substances can trigger surrounding cells to become senescent as well, causing signs of ageing to spread.
Research now focused on how this process works precisely in five different types of brain cells, including astrocytes and nerve cells. Each cell type appears to secrete its own combination of those harmful substances. Some brain cells react more strongly to these signals than others. For example, microglia appear to be very sensitive to reaching the senescent state through signals from other cells.
The researchers also investigated which substances play a role in transmitting the damage. They found that certain inflammatory factors and other molecules such as CCL2 and MIF are very important. With some medicines they could try to counteract the spread of these harmful signals, which met with partial success.
Although this research is important, it was carried out only at a cellular level in the laboratory. More studies in animals and eventually humans are needed to understand how these processes work in our brain. Understanding these mechanisms may help to potentially slow down ageing and brain diseases.
For anyone who wants to age healthily, it is important to know how ageing originates and spreads within brain cells. In the future, this may enable us to find better ways to counteract it.
Source: Josh Conway
