All tissue in the human body undergoes continuous reconditioning via changes in protein synthesis and breakdown. The speed of this synthesis can be determined by giving proteins a 'label'. Using this method, it was found that muscle tissue regenerates completely in three months. Human brain tissue, however, is harder to study because it's harder to obtain. Researchers were able to determine protein renewal in the brains of six patients at Maastricht UMC+ who were undergoing surgery for temporal lobe epilepsy. The results were surprising.

Four weeks
We know that the development of cognitive skills leads to structural changes in the brain; however, the possible role of protein synthesis and breakdown remained unknown. PhD research by Joey Smeets found that the synthesis speed of proteins in brain tissue is three to four per cent per day. This means all proteins in the brain are entirely replaced by new material every four to five weeks.

Fundamental process
While the exact implications of this finding remain unclear, it does shed new light on a fundamental process in the brain: the organ that stores data, interprets and processes information and regulates our personalities. 'The building blocks of brain tissue are regenerated in a month, but it's hard to determine the impact of this finding,' says Professor Luc van Loon (Human Biology). 'Rapid protein synthesis may play a leading role in this.'     

The Maastricht researchers recently published their results in the scientific journal Brain.