Mental Health Biomarkers and Apathy/Anhedonia

A look into Nubaira's research into pro-inflammatory biomarkers on depressive symptoms expressed in patients with Type 2 Diabetes Mellitus (T2DM).
Mental Health Biomarkers and Apathy/Anhedonia

This past summer, I worked at Sunnybrook Research Institute in Toronto interviewing patients and collecting blood samples. My research project explores how lipid-based molecules in the blood can actually help indicate the mental health state of patients. 

I worked specifically with Type 2 diabetic patients, as they are double as likely to experience depressive symptoms as normal population, engaging them through mood assessments, exercise and food diaries. 

In the past, we have seen that people who show increased depressive symptoms during winter months (previously known as SAD), also have increased lipid biomarkers in their blood. My work is trying to tie these same biomarkers to depressive symptoms expressed year round such as apathy, anhedonia, and impaired reward processing. 

To assess the mood and mental state of patients we used a variety of self-report tests: the Temporal Experience of Pleasure Scale (TEPS), Behavioural Inhibition and Stimulation Scales (BIS/BAS), Generalised Anxiety Disorder test (GAD), and more. Next summer, I am planning to begin testing using Apathy Evaluation Scale (AES), the Effort Expenditure for Reward Task (EEfRT), and Fatigue Assessment Scale (FAS). 

During patient interviews I collected blood samples and the lipid biomarker - oxylipin - was assayed via LC-MS/MS from fasting serum samples. Oxylipins are pro-inflammatory biomarkers that have been associated with mood impairment in the past. I am working to narrow down on the specific pathway that mediates this impairment: currently, my hypothesis is that oxylipins impair the reward-processing pathway in the brain, giving rise to anhedonia. To explore this I am trying to tie oxylipin levels in the blood to the results form mood assessments.

As an exploratory outcome measure, I am also using nuclear Magnetic Resonance Imaging (commonly MRI) to highlight how neuronal pathways in the brain are tied to impaired reward processing in T2DM patients, and if these signalling patterns (or lack of) are tied to oxylipin levels. 

Another facet of this research is the connection of mood to diet and exercise. Oxylipins are poly-unsaturated fatty acid metabolites i.e. they come from the fat we eat. Exercise, in turn, can help clear up these inflammatory molecules from our body. So if I am able to tie oxylipins to depressive states/symptoms, while controlling for diet (via food diary) and exercise (via GPAQ), we will be able to pinpoint a pathway for mood deterioration, and amelioration (actually, recently a University of Manchester study showed the therapeutic effects of diet on depression from 46000 patients!)

My experience so far has been incredibly rewarding. I have been able to engage with patients who have varied experience with their diabetes, and the comorbidities. I look forward to next summer, meeting more patients, and finalising the results of my study.  If you have any questions about the mood assessments, what its like working with patients, and my research in general, feel free to reach out!