Neurobiological Mechanisms Modulating Emotionality, Cognition and Reward-Related Behaviour in High-Fat Diet-Fed Rodents

Abstract

Affective and substance-use disorders are associated with overweight and obesity-related complications, which are often due to the overconsumption of palatable food. Both high-fat diets (HFDs) and psychostimulant drugs modulate the neuro-circuitry regulating emotional processing and metabolic functions. However, it is not known how they interact at the behavioural level, and whether they lead to overlapping changes in neurobiological endpoints. In this literature review, we describe the impact of HFDs on emotionality, cognition, and reward-related behaviour in rodents. We also outline the effects of HFD on brain metabolism and plasticity involving mitochondria. Moreover, the possible overlap of the neurobiological mechanisms produced by HFDs and psychostimulants is discussed. Our in-depth analysis of published results revealed that HFDs have a clear impact on behaviour and underlying brain processes, which are largely dependent on the developmental period. However, apart from the studies investigating maternal exposure to HFDs, most of the published results involve only male rodents. Future research should also examine the biological impact of HFDs in female rodenrts. Further knowledge about the molecular mechanisms linking stress and obesity is a crucial requirement of translational research and using rodent models can significantly advance the important search for risk-related biomarkers and the development of clinical intervention strategies.

The Effect of Fat Intake with Increased Omega-6-to-Omega-3 Polyunsaturated Fatty Acid Ratio in Animal Models of Early and Late Alzheimer’s Disease-like Pathogenesis

“…The effect on cognition in rodents exposed for a long period to an HFD remains debatable, and differences may be considered by diet composition, time of exposure, age and gender of the animals, and/or genetic differences between individual specimens [40][41][42][43][44][45][46]. According to the reported findings in rodent strains, the strong effects of HFD treatment on cognitive performance were observed in both young and adolescent animals; however, a small number of studies employed adult animals [47].…”

A maternal high-fat diet during pregnancy and lactation induced depression-like behavior in offspring and myelin-related changes in the rat prefrontal cortex

“…In accordance with the developmental origins of health and disease, early-life environmental exposures, such as maternal diet, can enhance the probability and gravity of health concerns in their offspring in the future ( Barker, 2007 ; Armitage et al, 2008 ). The preclinical studies suggest a relationship between maternal high-fat diet (HFD) and neuropsychiatric disorders including autism spectrum disorders ( Gawlińska et al, 2021a , c ), cognitive impairment ( Ziemens et al, 2022 ; Smaga et al, 2023 ), schizophrenia ( Sarker et al, 2019 ), depression ( Giriko et al, 2013 ; Gawlińska et al, 2020b ; Gawliński et al, 2021 ), and substance use disorder ( Gawliński et al, 2020 ). Some investigators also showed that maternal HFD reduces social interactions and increases repetitive behavior ( Ergaz et al, 2016 ; Gawlińska et al, 2020b , Gawlińska et al, 2021c ), as well as evokes the disturbances in short-term memory ( Smaga et al, 2023 ), social memory and sensorimotor gating deficits ( Bordeleau et al, 2021 ).…”