Scientists map gene expression of each brain cell during aging process

Examination of fruit flies' brains generated more than one billion data points for scientists to analyse

A team of scientists has become the first to map the gene expression of each individual brain cell during aging.

Using a fruit fly as the first test subject, the research, which was lead by Professor Stein Aerts, was able to create a "cell atlas", which provides insights into the workings of the brain as it ages.

Published in the scientific journal Cell, the research of the atlas has been touted as an important first step in the development of techniques that can help us gain a better understanding of human disease development.

The researchers catalogued more than 80 different cell type clusters, and found that not all of them age in the same way

The fruit fly brain consists of some 100,000 different cells, and although that makes it much smaller than that of a person's, it contains hundreds of different types of neurons and other cells forming a complex network, much like the human brain.

Kristofer Davie, one of the many researchers involved in the research effort, explains it was no easy task mapping the cells on such a small organism as it required zooming in on each and every individual cell.

"There are about 15,000 genes and roughly 100,000 cells in the fly brain. So a quick calculation shows we are looking at more than a billion data points to analyse and map over time," Davie said.

The only way the scientists were able to mine this large amount of data is with help from artificial intelligence. The team used machine-learning methods to accurately predict the age of a cell, based on information gathered from brain cells of flies at different ages.

Similar to our brain, flies' brain have distinct cells responsible for sleep, memory, smell, and so on. The researchers catalogued more than 80 different cell type clusters, and found that not all of them age in the same way.

According to Aerts, the main driver of the research is to eventually assess the molecular state of a patient's tissues and cells in real time, enabling early diagnosis of disease and effective, personalised treatments.

"But to get there we need to develop both the models and the tools to understand the dynamics of cellular changes," he added.

Developing biomedical applications will require more work, and more collaborations, though, hence why Aerts is part of a large pan-European consortium, called LifeTime, which aims to revolutionise healthcare by tracking and understanding cellular changes during disease.