Time-restricted feeding prevents memory impairments induced by obesogenic diet consumption in mice, in part through hippocampal thyroid hormone signaling.
Ontology highlight
ABSTRACT: Objective: The early consumption of calorie-rich diet disrupts circadian rhythms and has adverse effects on memory, yet the effects of timerestricted feeding (TRF) and the underlying molecular mechanisms are unknown. Here, we set out to identify the behavioral and molecular circadian rhythms disruptions generated by juvenile obesogenic diet consumption and their restoration by TRF in male mice. Methods: Metabolic rhythms were measured by indirect calorimetry and memory performances by behavioral tasks. Hippocampal translatome (pS6_TRAP), enrichment and co-regulated gene network analyses were conducted to identify the molecular pathways involved in memory impairments and their restoration by TRF. Differential exon usage analyses, mass spectrometry and pharmacological intervention were used to confirm thyroid hormone signaling involvement. Results: We show that four weeks of TRF restore the rhythmicity of metabolic parameters and prevents memory impairments in mice fed a high fat-high sucrose (HFS) diet since weaning, independently of body fat levels. Hippocampal translatome and differential exon usage analyses indicate that impaired memory of mice under ad libitum HFS diet is accompanied by reduced thyroid hormone signaling and altered expression of astrocytic genes regulating glutamate neurotransmission. TRF restored the diurnal expression variation of part of these genes and intrahippocampal infusion of T3, the active form of thyroid hormone, rescues memory performances and astrocytic gene expression of ad libitum HFS diet-fed mice. Conclusions: Thus, thyroid hormones contribute to the TRF positive effects on both metabolism and memory in mice fed an obesogenic diet, highlighting this nutritional approach as a powerful tool in addressing obesity brain comorbidities and paving the way for further mechanistic studies on hippocampal thyroid signaling.
Project description:Adipose tissue metabolism is actively involved in the regulation of energy balance. Adipose-derived stem cells (ASCs) play a critical role in maintaining adipose tissue function through their differentiation into mature adipocytes. The aim of this study was to investigate the effect of an obesogenic environment on the epigenetic landscape of ASCs and its impact on adipocyte differentiation and its metabolic consequences. Our results showed that ASCs from mice fed a high-fat sucrose (HFS) diet exhibited reduced adipogenic capacity, increased fat accumulation, and formed larger adipocytes than those from the control group (C). The results showed that ASCs from mice fed the HFS diet had reduced adipogenic capacity. Mitochondrial analysis showed increased mitochondrial activity in undifferentiated ASC-HFS, but decreased respiratory and glycolytic capacity in mature adipocytes. The HFS diet significantly altered the H3K4me3 acetylation profile of ASCs in genes related to adipogenesis, mitochondrial function, inflammatory response and immunomodulation. After differentiation, adipocytes retained H3K4me3 alterations in genes related to inflammatory response and immunomodulation. RNA-seq confirmed the upregulation of genes associated with inflammatory and immunomodulatory pathways in adipocytes. This study demonstrates that HFS diet induces profound epigenetic and transcriptomic changes in ASCs, leading to impaired differentiation and dysfunctional adipocyte formation.
Project description:Adipose tissue metabolism is actively involved in the regulation of energy balance. Adipose-derived stem cells (ASCs) play a critical role in maintaining adipose tissue function through their differentiation into mature adipocytes. The aim of this study was to investigate the effect of an obesogenic environment on the epigenetic landscape of ASCs and its impact on adipocyte differentiation and its metabolic consequences. Our results showed that ASCs from mice fed a high-fat sucrose (HFS) diet exhibited reduced adipogenic capacity, increased fat accumulation, and formed larger adipocytes than those from the control group (C). The results showed that ASCs from mice fed the HFS diet had reduced adipogenic capacity. Mitochondrial analysis showed increased mitochondrial activity in undifferentiated ASC-HFS, but decreased respiratory and glycolytic capacity in mature adipocytes. The HFS diet significantly altered the H3K4me3 acetylation profile of ASCs in genes related to adipogenesis, mitochondrial function, inflammatory response and immunomodulation. After differentiation, adipocytes retained H3K4me3 alterations in genes related to inflammatory response and immunomodulation. RNA-seq confirmed the upregulation of genes associated with inflammatory and immunomodulatory pathways in adipocytes. This study demonstrates that HFS diet induces profound epigenetic and transcriptomic changes in ASCs, leading to impaired differentiation and dysfunctional adipocyte formation.
Project description:To gain insight into the mechanism(s) by which obesogenic diet caused decreased uterine contractility at term, we collected uterine tissue from mice fed either a control (CON) or an obesogenic (DIO) diet at day 18.5 of pregnancy and performed RNA sequencing.
Project description:Chronic high-fat/high-sugar (HFS) feeding is linked to the development of insulin resistance as well as arterial wall and adipose tissue inflammation in nonhuman primates. These changes are significantly reduced when the animals are fed a HFS diet supplemented with resveratrol (RSV) for two years. Herein, we evaluated the occurrence of cerebral cortex injury in these HFS-fed middle-aged male rhesus monkeys and investigated the possibility of brain protection by RSV treatment. HFS caused a reduction in capillary density in the cerebral cortex that was preempted by RSV supplementation. The patterns of cDNA microarray analysis revealed upregulation of markers of oxidative stress, inflammation and apoptosis in the cortical cortex of HFS-fed monkeys, which was reversed by RSV. The underlying mechanism of RSV action included its ability to prevent the HFS-mediated NF-kappa-B activation and loss in mitochondrial aldehyde dehydrogenase 2 expression. We conclude that RSV may confer neuroprotection against HFS-mediated cerebral vascular dysfunction and activation of inflammatory pathways.
Project description:Time-restricted feeding prevents memory impairments induced by obesogenic diet consumption in mice, in part through hippocampal thyroid hormone signaling.
Project description:We profiled the gut microbiome and chromatin features at DNA cis-regulatory elements in colon epithelium from mice fed either an obesogenic or control diet.
Project description:Gestational diabetes mellitus (GDM) exposure and obesity are strong risk factors for type 2 diabetes development; however, the connections between GDM exposure, postnatal diet and islet dysfunction in offspring metabolic health remain unclear. Reduced glucose-stimulated insulin secretion was observed in islets isolated from 15-week-old offspring prenatally exposed to GDM, which was exacerbated by postnatal HFS consumption. In the HFS-fed offspring of Lean dams, islet size and number increased, an adaptation that was not observed in the HFS-fed offspring of GDM dams. Islets from GDM exposed offspring revealed upregulation of 102 genes (e.g. Sod2, Il1b) and 13 downregulated genes. In the GDM offspring that consumed a postnatal HFS-diet, 126 genes were significantly upregulated (e.g. Ccl2, Rps14, Atp5f1) and 17 genes were downregulated (e.g. Hnf1a, Slc2a2). These results demonstrate that GDM exposure induced changes in gene expression in the young adult rat offspring that worsen islet function and whole-body glucose homeostasis.