Weight gain and neuroadaptations elicited by high fat diet depend on fatty acid composition

Louise Adermark; Saray Gutierrez; Oona Lagström; Maria Hammarlund; Valentina Licheri; Maria E Johansson

doi:10.1016/j.psyneuen.2021.105143

Weight gain and neuroadaptations elicited by high fat diet depend on fatty acid composition

Psychoneuroendocrinology. 2021 Apr:126:105143. doi: 10.1016/j.psyneuen.2021.105143. Epub 2021 Jan 19.

Authors

Louise Adermark¹, Saray Gutierrez², Oona Lagström³, Maria Hammarlund², Valentina Licheri³, Maria E Johansson²

Affiliations

¹ Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Sweden; Deparment of Pharmacology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Sweden. Electronic address: Louise.adermark@gu.se.
² Department of Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Sweden.
³ Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Sweden.

PMID: 33493754
DOI: 10.1016/j.psyneuen.2021.105143

Abstract

Overconsumption of food is a major health concern in the western world. Palatable food has been shown to alter the activity of neural circuits, and obesity has been linked to alterations in the connectivity between the hypothalamus and cortical regions involved in decision-making and reward processing, putatively modulating the incentive value of food. Outlining neurophysiological adaptations induced by dietary intake of high fat diets (HFD) is thus valuable to establish how the diet by itself may promote overeating. To this end, C57BL/6 mice were fed HFD rich in either saturated fatty acids (HFD-S) or polyunsaturated fatty acids (HFD-P), or a low-fat control diet (LFD) for four weeks. Food and energy intake were monitored and ex vivo electrophysiology was employed to assess neuroadaptations in lateral hypothalamus (LH) and corticostriatal circuits, previously associated with food intake. In addition, the effects of dietary saturated and polyunsaturated fatty acids on the gene expression of NMDA, AMPA and GABA_A receptor subunits in the hypothalamus were investigated. Our data shows that mice fed HFD-P had increased daily food and energy intake compared with mice fed HFD-S or LFD. However, this increase in energy intake had no obesogenic effects. Electrophysiological recordings demonstrated that HFD-P had a selective effect on glutamatergic neurotransmission in the LH, which was concomitant with a change in mRNA expression of AMPA receptor subtypes Gria1, Gria3 and Gria4, with no effect on the mRNA expression of NMDA receptor subtypes or GABA_A receptor subtypes. Furthermore, while synaptic output from corticostriatal subregions was not significantly modulated by diet, synaptic plasticity in the form of long-term depression (LTD) was impaired in the dorsomedial striatum of mice fed HFD-S. In conclusion, this study suggests that the composition of fatty acids in the diet not only affects weight gain, but may also modulate neuronal function and plasticity in brain regions involved in food intake.

Keywords: Lateral hypothalamus; Medial prefrontal cortex; Plasticity; Polyunsaturated fatty acids; Saturated fatty acids.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Diet, High-Fat*
Fatty Acids*
Fatty Acids, Unsaturated
Mice
Mice, Inbred C57BL
RNA, Messenger
Receptors, GABA-A
Weight Gain*

Substances

Fatty Acids
Fatty Acids, Unsaturated
RNA, Messenger
Receptors, GABA-A