Metabolic profiling uncovers links between lifestyle and metabolic health
On October 2nd, 2020, Stefania Noerman defended her doctoral thesis entitled “Finding molecular links between lifestyle factors and indicators of metabolic health – a nontargeted metabolic profiling approach” at the University of Eastern Finland, Kuopio. Her thesis examined the association of various blood metabolites, including lipids and those derived from the gut microbiota, with both lifestyle factors and the indicators of metabolic health. In the thesis, the lifestyle factors were represented by diet and psychological well-being, whereas metabolic health was represented by the risk factors and type 2 diabetes and coronary artery disease incidence.
As we may know, lifestyle factors play an important role in determining the risk of metabolic diseases. However, the contribution of each of these lifestyle factors, such as diet and psychological stress, is not well established. The application of nontargeted metabolomics approach now can provide a comprehensive metabolite profile related to certain or changes in health status of individuals. It hence may open the possibility to generate hypotheses on the link between lifestyle factors and metabolic health.
The doctoral thesis aimed to evaluate the molecular links between lifestyle factors and metabolic health to generate hypotheses on the potential mechanisms. Specifically, the thesis discusses the application of nontargeted metabolomics to characterise potential molecules and molecular pathways involved in the association between dietary factors, psychological stress, and well-being. The dietary factors examined in this thesis were represented by the consumption of eggs to exemplify a single dietary component and adherence to the healthy Nordic diet as an example of the whole dietary pattern. These molecules and pathways were then associated with the risk factors of getting type 2 diabetes and coronary artery disease. The samples were taken from subsets of prospective cohort Kuopio Ischaemic Heart Disease Risk Factor Study and multi-center Elixir lifestyle intervention study. The nontargeted metabolic profiling employed in the thesis projects utilised a combined system of liquid chromatography coupled with mass spectrometry, which enables extensive analysis of metabolites with various chemical properties.
The results highlighted both previously established and novel associations between some metabolites with lifestyle factors, the indicators of physiological and psychological well-being, and the risk of metabolic diseases. Lipid metabolites, such as phospholipids, plasmalogens, and other lipophilic molecules seemed important in the link between examined lifestyle factors and metabolic profile, despite differences in the lipid species and the inconsistent associations across studies. The results also support the hypothesis of shared mechanisms between physiological and psychological well-being, tightly connected with inflammation. The association between gut microbial metabolites and the risk factors of metabolic diseases highlights the possible contribution of gut microbiota, as well as other factors than diet, in the interaction between adherence to the healthy Nordic diet and incidence of coronary artery disease.
“These findings once again emphasised the importance of lifestyle management to maintain metabolic health. However, further investigations are still needed to reveal the mechanisms how these lifestyle factors would affect the metabolic profile of each individual”, Noerman said. When being asked about how her PhD experience, she said, “I think it is overall a great experience. I got a chance to meet many inspiring people, learn many new things, develop myself professionally and personally. I could even visit many places before the pandemic started. For me, PhD is not a degree I pursued anymore, but a journey where I thought I do the same thing every day, but at the end of the journey, I realized that I had become a different person”, she closed.
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