Breath in, breath out. Breath in, breath out. An adult breathe in and out about 12 to 18 times a minute, usually without thinking about it. The goal of the maneuver: to bring oxygen to the trillion cells of the body.
Respiration on a large scale is followed by breathing on a small scale, called cellular respiration. It ensures that cells from food and oxygen gain energy - which is one of the foundations for the body to function as a whole.
But cells do not just breathe. They also feel how much oxygen they have available and adjust accordingly.
The two Americans William Kaelin and Gregg Semenza and the Briton Peter Ratcliffe have explored how this mechanism works. For their work, the three will now be honored with the Nobel Prize for Physiology or Medicine 2019.
TT News / REUTERS; THE MIRROR
Oxygen sensors in the cell
Cells have to cope with changing oxygen supply over and over again, not only in case of illness, but also during sports or in the mountains.
Gregg Semenza of the Johns Hopkins Institute for Cell Engineering in Baltimore discovered a protein that serves as an oxygen sensor in the cells, the so-called HIF, short for: Hypoxia Inducible Factor.
If there is plenty of oxygen, a cell hardly contains HIF. When oxygen is lacking, the amount of HIF increases, which in turn affects the activity of genes in the cell.
Why does the HIF concentration fluctuate? In the meantime, people know that the cell uses a lavish but sophisticated process. It is constantly producing new HIF molecules and is steadily reducing them. However, the disposal only works if there is oxygen. For this reason, HIF accumulates in the cells when there is a lack of oxygen.
William Kaelin from Boston's Harvard Medical School conducted research on the protein VHL, which is linked to cancer and is also more or less active, depending on its oxygen content. Peter Ratcliffe found out that there is a connection between HIF and VHL. Ratcliffe is Director of Clinical Research at the Francis Crick Institute in London and the Target Discovery Institute in Oxford.
Hope for healing
Because oxygenation plays a role in many diseases, it is hoped that the work of Ratcliffe, Kaelin and Semenza will help to develop new therapies such as anemia, wound healing or even cancer.
For example, boosting the action of HIF can stimulate the formation of red blood cells. Anemia-based medicines, which are ultimately based on the work of the three Nobel Prize winners, are already being tested in clinical trials.
The hope is that the findings will help to develop new therapies for some forms of cancer. Such medicines would do the opposite of what an antidiarrheal agent does: they would not support HIF but block it. Among other things, this could counteract the formation of new blood vessels that tumors need to grow. However, there is still a long way to go to develop such medicines and it is quite possible that this approach will not provide new cancer medicines.
But even if this year's Nobel Prize does not bring the key to curing cancer, it has provided important insights into how the cells of the body sense if they have enough oxygen. In this sense: inhale, exhale.