As the world population gets increasingly older, we need to understand how to avoid age-related diseases. One important part of this is to understand ageing on a cellular level. Research on cells is usually done through experiments in a laboratory, and in that way a lot of isolated processes in the cells have been analysed. But the cell ageing is also characterised by the interactions of these processes, and the interactive and multi-scale dimensions are not always possible to study in a laboratory environment. To get a broader insight on how cells age, this project has been using mathematics in the form of different models for different cellular processes closely connected to ageing.
Mathematical models to describe cellular processes
The three chosen processes are the signalling system, which is able to sense changes in the cellular environment; the metabolism, which converts food into energy; and damage accumulation, which defines ageing in Barbara’s project. Depending on the available details of the biology, these networks have been translated into Boolean models, optimisation models (so-called flux balance analysis), and ordinary differential equations.
– All models have been combined to get an understanding of how the processes interact, since this interaction is important when the cell loses its function. The results are different predictions and suggestions on how these interactions work. The next step would be for the biologists to take, through verification experiments in the laboratory. The results can also be further built upon through adding more cellular processes and defining the connections between them.
Erasmus exchange led to Gothenburg
Barbara’s Bachelor degree, which she took in Germany, was neither in mathematics nor biology but in physics. She went to the University of Gothenburg in a six-month Erasmus exchange and there found the Master programme Complex Adaptive Systems which appealed to her. The programme included courses in computational biology, and when doing her Master’s thesis the PhD position that Barbara has had turned up. For the last two years she has worked closely to PhD Linnea Österberg, an experimentalist and biologist working in the same project group who defended her thesis on April 29. From the beginning they had separate projects, but the cooperation evolved naturally and they have had the benefit of going through the PhD work together.
– A highlight during these years was when we gave a popular science talk called “A mathematician and a biologist walk into a bar” (En matematiker och en biolog går in i en bar, on UR Play) during the International Science Festival Gothenburg. Since it was in the year of 2021 it was digital, sent live from a studio, which was an interesting experience even if I was nervous. I think it is important for scientists to be able to explain what we do.
Barbara has liked living in Gothenburg and finds the PhD conditions in Sweden good, since it is like a normal job with a secure employment and fixed salary. In the beginning she lived with a Swedish girl and chose to speak Swedish all the time, which together with some courses gave her a good knowledge of the language. The research language is however always English, so it is easier to talk about work in English. Barbara has also taught courses, mostly basic mathematics courses but also a master’s course. She found it hard in the beginning but kind of grew into it, and now sees it as a nice experience. Now, she will start looking for a job in industry.
Barbara Schnitzer will defend her PhD thesis “Mathematical Modelling of Cellular Ageing: A Multi-Scale Perspective” on May 13 at 10.15 in lecture hall Pascal, Hörsalsvägen 1, and via Zoom. Supervisor is Marija Cvijovic, assistant supervisor Niek Welkenhuysen
Text: Setta Aspström
Photo: Linnea Österberg