Dataset Information

Deficiency of hypothalamic taste receptor type 1 member 3 prevents western diet-induced anxiety in mice

ABSTRACT: Accumulating studies support that the western diet (WD), a diet comprised of saturated fat and sugary drinks, contributes to the pathogenesis of anxiety disorders, the most prevalent mental disorders worldwide. However, the underlying mechanisms by which WD causes anxiety, remain unclear. Abundant expression of taste receptor type 1 member 3 (TAS1R3) is identified in the hypothalamus, a key brain area involved in both sensing peripheral nutritional signals and regulating anxiety. Thus, we investigated the role of the hypothalamic TAS1R3 in WD-induced anxiety using wild-type (WT) and Tas1r3 deficient (Tas1r3-/-) mice fed a normal diet (ND) or WD for 12 weeks. We evaluated anxiety levels with the open field test and the elevated plus maze test. Behavior tests showed WD increased anxiety in WT mice, whereas Tas1r3-/- mice were protected from WD-induced anxiety. Analyzing the hypothalamic transcriptome of WD-fed WT and Tas1r3-/- mice, we found 1,437 genes significantly regulated by Tas1r3 deficiency. In addition, bioinformatic analysis revealed that CREB-mediated maintenance of neuronal regeneration, which can prevent the development of anxiety, was enhanced in WD-fed Tas1r3-/- mice compared to WD-fed WT mice. In addition, in vitro studies further confirmed that Tas1r3 knockdown prevented suppression of CREB caused by high levels of glucose, fructose, and palmitic acid in adult hypothalamic neuronal cells. These results imply that TAS1R3 may play a key role in WD-induced alterations in hypothalamic functions, and inhibition of TAS1R3 overactivation in the hypothalamus could offer therapeutic targets to alleviate the effects of the WD on anxiety.

ORGANISM(S): Mus musculus

PROVIDER: GSE216063 | GEO | 2023/08/05

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Purpose: Excessive intake of a western diet (WD), characterized by high fat and sugary drinks, is hypothesized to contribute to the development of inflammatory bowel disease (IBD). Despite the identified clinical association, the molecular mechanisms through which dietary changes lead to IBD development remain unknown. Here, we generated a murine model of severe intestinal inflammation triggered by long-term WD consumption, which exhibited markedly elevated taste receptor TAS1R3 expression in inflamed bowel tissues. Thus, we hypothesized that nutrient-induced TAS1R3 modulation is central to regulating intestinal inflammation. We tested our hypothesis by analyzing changes in gene expression profiles and inflammatory cell infiltration in the inflamed bowel tissues of WD-fed Tas1r3-deficient mice. Methods: We carried out RNA-Seq of ileum tissue of wild-type (WT) and taste receptor Tas1r3 knockout (Tas1r3−/−) mice fed a normal diet (ND) or western diet (WD) for 10 weeks using Ion Proton System. Raw RNA-seq reads were split into individual samples based on barcodes and quality controlled using the FASTQC tool. The reads were analyzed with Partek Flow software (Partek, St. Louis, MI, USA) (http://www.partek.com/partekgs). The sequence reads that passed quality filters were analyzed at the transcript isoform level. Results: We confirmed that Tas1r3-deficient mice are protected from WD-induced intestinal inflammation. Consistent with little or no phenotypic change in the ND group, the gene expression profiles from the ND-fed Tas1r3−/− and WT mice were similar, whereas the ileal transcriptome profiles from the WD-fed Tas1r3−/− mice were readily distinguishable from those of WD-fed WT mice. Inflammatory cytokines such as Tnfα and Il1b were highly expressed in WD-fed WT mice, whereas Pparg, Tjp3, and Defa27 were highly expressed in WD-fed Tas1r3−/− mice. Importantly, we confirmed that the absence of TAS1R3 caused a significant reduction in the inflammatory response-related signaling pathway; GSEA plots also revealed that the mTOR signaling pathway was greatly suppressed. Most notably, the PPAR signaling pathway was significantly affected by TAS1R3 absence. GSEA confirmed that genes associated with the PPAR signaling pathway were significantly enriched in the set of DEGs between Tas1r3−/− and WT mice in the WD groups. Conclusion: Our data suggest that, due to its suppressive action on mTOR, TAS1R3 might function as an important regulator of the PPAR-γ signaling pathway in the intestinal tract.

Project description:The crucial role of nutrition for cerebral health and the impact of dietary habits on brain structure and function have been long far recognized. To date a major health concern is associated with the increased consumption of fructose as added sugar in many types of drinks and processed foods, especially among young people. High-fructose intake has been pointed out as the possible culprit for the raised incidence of chronic diseases, such as obesity, cardiovascular disease, nonalcoholic fatty liver disease, and type 2 diabete. Further, it has been reported that high-fructose intake is associated with the over-activation of its cerebral metabolism, which was proposed to negatively impact on whole brain physiology and cognitive function. Notably, we previously reported that short-term fructose-rich diet induces mitochondrial dysfunction, oxidative stress, and neuroinflammation in hippocampus of young rats, as well as the imbalance of redox homeostasis, autophagic mechanisms and representation of synaptic markers in frontal cortex of both adult and young rats. Animal studies have also revealed the damaging effect of high-fructose diets on hippocampal functions during periods of neurocognitive development, such as childhood and adolescence. Hypothalamus plays a crucial role in maintaining whole body homeostasis. Long-term fructose overfeeding was reported to alter hypothalamic-pituitary-adrenal axis, leading to elevations in glucocorticoids in peri-adolescent rats [22]. Further, fructose overconsumption was associated with impairment of hypothalamic insulin signalling, oxidative stress and inflammation , and it was proposed that fructose-driven perturbations of hypothalamic function may compromise the potential for satiety, thereby increasing the prospect of developing obesity. Data currently available on hypothalamic dysfunctions related to a high-fructose diet essentially refer to the effects of long-term sugar feeding, while information on corresponding alterations associated with a short-term dietary treatment, particularly in the critical period of adolescence, is still lacking. Due to complexity and multiplicity of hypothalamic functions, there is also the need for a holistic characterization aimed at unveiling the general picture of hypothalamic dysfunctions associated with a high-fructose diet. To fill this gap, we investigated adolescent rats fed a fructose-rich or control diet, for 3 weeks. To verify whether the fructose-driven changes are rescued after the switch to a control diet, half of the rats from both animal groups were then fed a control diet for additional 3 weeks until young adulthood phase. Quantitative proteomics on hypothalamic extracts of all animal groups was used to identify molecular alterations triggered by fructose-rich diet and to obtain insights into the relationship between sugar feeding and possible dysfunctions of hypothalamus.

Dataset Information

Deficiency of hypothalamic taste receptor type 1 member 3 prevents western diet-induced anxiety in mice

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure