The doctoral dissertation in the field of Molecular Medicine will be examined at the Faculty of Health Sciences at Kuopio campus. The public examination will be streamed online.
What is the topic of your doctoral research? Why is it important to study the topic?
My thesis investigates how air pollution ultrafine particles, largely derived from road traffic emissions, affect the olfactory mucosa cells, which are located at the crossroads of the environment and the brain. Due to their small size, ultrafine particles can reach even the brain and contribute to the development of neurodegenerative diseases, such as Alzheimer's disease. There is an urgent need to understand the complex mechanisms of how different constituents of air pollution, especially ultrafine particles, affect our health. Evidence is needed to steer the political decision-making for setting limits to UFPs, which are currently not monitored or regulated by any legislation. This research is a burning topic in the world, where the population's life expectancy is ever-increasing, and air pollution is a major threat to health. Increasing evidence of these particles facilitates risk assessment, which supports political decision-making.
What are the key findings or observations of your doctoral research?
The results revealed that ultrafine particles cause substantial alterations in cellular functions involving cellular energy metabolism, olfactory signalling, and epithelial permeability. These findings increase the understanding of how ultrafine particles may translocate to the brain and what changes they can induce in the brain, leading, for example, to Alzheimer’s disease. In addition, it appears that cells derived from individuals with Alzheimer’s disease are more sensitive to ultrafine particle-induced effects, indicative of increased sensitivity of Alzheimer’s disease patients to air pollution. The results also demonstrate the importance of engine aftertreatment devices to diminish the adverse effects of exhaust emissions and suggest that renewable diesel with lower aromatic content induces less harmful responses in comparison to fossil diesel.
How can the results of your doctoral research be utilised in practice?
This dissertation provides important information on the increased sensitivity of Alzheimer's disease patients to the effects of air pollution. By understanding the differences between healthy individuals and those with Alzheimer's disease, we will gain better tools for identifying risk groups and for preventive measures and treatment. In addition, my findings on different diesel emissions also provide evidence on the effects of different fuel and engine technologies on the harmfulness of emissions. Replacing the entire world's vehicle fleet with electric or hybrid cars is not realistic, so I believe that there is a demand for evidence on the effects of different fuel and engine technologies on diesel emissions. The results of my research have an impact not only on decision-makers and environmental agencies, but also on individuals belonging to risk groups. The studies of this dissertation were part of the EU Horizon 2020-funded research project “Transport derived Ultrafines and the Brain Effects” (TUBE), which was reported to the EU Commission, providing information to support political decision-making.
What are the key research methods and materials used in your doctoral research?
This project was carried out in Professor Katja Kanninen’s research group. This research utilised multiple different research methods, including, for example, primary cell cultures, real-life diesel emission samples, RNA and miRNA-sequencing, DNA methylation analysis, different toxicity assays, and functional studies. The primary olfactory cell model was derived from nasal biopsies from living subjects collected in collaboration with Kuopio University Hospital, including experts from the departments of otorhinolaryngology and memory-related disorders and the Brain Research Unit at the University of Eastern Finland. VTT Technical Research Centre of Finland and the University of Tampere provided and characterised the diesel-emission samples, coordinated by my other supervisor, Professor Pasi Jalava.
In addition to the TUBE project, the study has also received funding from the Kuopio Area Respiratory Foundation, the Finnish Brain Foundation, Yrjö Jahnsson Foundation, Päivikki and Sakari Sohlberg Foundation, the Finnish Cultural Foundation’s North Savo Regional Fund and Kuopio University Foundation.
I’d like to express my gratitude to all of those individuals and their families who participated in this study by donating their precious olfactory mucosa cells, enabling our cell model. I’d also like to thank all the funding foundations for making my full-time research possible.
The doctoral dissertation of Laura Mussalo, MSc (Pharm), entitled Ultrafine particulate matter and neurodegeneration – olfactory mucosa at the crossroads will be examined at the Faculty of Health Sciences. The Opponent in the public examination will be Professor Theo de Kok of Maastricht University, and the Custos will be Professor Katja Kanninen of the University of Eastern Finland. The public examination will be held in English.
For further information, please contact:
Laura Mussalo, MSc (Pharm), [email protected], 040 5546820, https://uefconnect.uef.fi/en/laura.mussalo/
