Link between the consumption of ultra-processed foods and drinks and major depressive

Research project description

A PhD position is available at the Department of Psychiatry and Legal Medicine from the Universitat Autònoma de Barcelona in collaboration with Sant Pau Mental Health Research Group under the supervision of Oren Contreras and Narcis Cardoner. We are looking for a highly motivated candidate that will investigate the importance of the consumption of ultra-processed foods and drinks (UPF) in the advent of depression.

There is burgeoning interest in identifying factors that palliate the high prevalence and

disability of major depressive disorders (MDD). Epidemiological evidence highlights the

importance of the consumption of ultra-processed foods and drinks (UPF) in the advent of depression. Beyond its poor nutritional composition, UPF have an increased number of additives, some of them containing nanoparticles, and the potential presence of components derived from food processing (e.g., acrylamide) and package (e.g., bisphenols or phthalates).

Preclinical studies showed that some UPF components produce cytotoxicity and neuroinflammation in glial and neuron cells. In population-based samples, we have found UPF consumption to be positively associated with depressive symptoms, and negatively with the volume in corticolimbic brain networks, with inflammatory factors plating a role. In addition, rats consuming our own developed UPF diet from weaning showed depressive-like behaviors and higher tryptophan in the frontal cortex compared to those under a standard diet. However, there is a significant knowledge gap on the effects that UPF consumption has on MDD, their contribution to treatment-resistance, and the mechanisms underlying these alterations in the context of whole diet in humans. UPF-induced alterations in the gut microbiota-brain axis may be one potential mechanism.

In MDD, we will investigate (1) the cross-sectional association between UPF consumption, the severity of depressive symptoms, and the functioning within mesocorticolimbic brain networks, (2) the longitudinal association with antidepressant treatment effectiveness and resistance, and (3) the influence of the basal brain network functioning on this previous association. Finally, we will test the role of UPF-induced alterations in gut-metabolite and microbiota concentrations on these associations. Obtained results will be compared with the behavior and serotonergic system of rats fed an already-design UPF diet.

The successful candidate will be enrolled in the PhD Psychiatry doctoral program at the Universitat Autònoma de Barcelona (UAB) in the framework of the TOUCH project. TOUCH (“Towards the next generatiOn of excellent yoUng doctoral researchers on mental health by developing an intersectoral & transdisciplinary approaCH”) is a new excellent doctoral programme co-funded by the Marie Skłodowska-Curie (MSCA) Actions of the European Commission and led by the UAB for the recruitment and training of 24 doctoral candidates in the field of mental health and wellbeing.

Academic background / Skills

The candidates must fulfil the following eligibility criteria from the EC: Mobility rule: candidates must not have resided or carried out their main activity (work, studies, etc.) in Spain for more than 12 months in the 36 months immediately preceding the deadline for the programme call. Experience rule: researchers must be doctoral candidates at the date of recruitment, i.e. not already in possession of a doctoral degree at the deadline of the open calls. Researchers who have successfully defended their doctoral thesis but have not yet formally awarded the doctoral degree will not be considered eligible. Candidates must hold a degree that allows admission to the official doctoral programme at UAB.

Additional requirements for a stronger application are:

We expect candidates with a Bachelor in the fields of Psychology, Biomedicine, Biomedical Engineering, Medicine or related.

Motivation to perform research linked to the topic of the project (e.g., Nutritional Psychiatry).

Experience in the use of statistical packages (e.g., SPSS, R).

Experience or motivation to learn statistical approaches to analyze structural and functional brain imaging data with the use of specialized packages (e.g., MATLAB, SPM, CONN).

The applicant should be able to perform team oriented as well as independent work.

• Working with a focus on objectives and results.

• Careful in their tasks.

Motivation to assume new intellectual challenges and interact with an interdisciplinary group of psychiatrists, psychologists, and biologists.

Interested applicants are encouraged to contact the investigators for further information oren.contreras@uab.cat, narcis.cardoner@uab.cat

Research group/s description

We are an interdisciplinary team of psychiatrists, biologists, and psychologists involved in an ambitious research program that combines pre and clinical studies to understand the link between UPF consumption and depression.

We have extensive experience with the etiopathology and neural underpinnings of MDD (1) and the mechanisms of action and effectiveness of psychotherapeutic and pharmacological treatments (2). We led the first review on the potential mechanism of UPF features on brain changes (3) and the association of UPF consumption, depressive traits (4,5), and brain features (5). Clinical results will be complemented with comprehensive assessments of the serotonergic system in rats pre and postnatally exposed to a UPF diet. The effects of UPF consumption through the gut microbiotabrain axis have been indirectly investigated in obesity conditions (6,7), and this will be explored directly in MDD in the present project.

SGR groups: 2021SGR00832 Research group in Mental Health Sant Pau, 2021SGR01017 Clinical-Biological Psychiatry and Psychology Research Group. (1) Serra-Blasco et al., 2021; (2) Cano et al., 2017; (3) Contreras-Rodríguez et al., 2022; (4) Reales-Moreno et al., 2022; (5) Contreras-Rodríguez et al., 2023; (6) Arnoriaga et al., 2020; (7) Arnoriaga et al., 2022.