An Atherogenic Diet Disturbs Aquaporin 5 Expression in Liver and Adipocyte Tissues of Apolipoprotein E-Deficient Mice: New Insights into an Old Model of Experimental Atherosclerosis

Abstract

The dysfunction of vascular endothelial cells is profoundly implicated in the pathogenesis of atherosclerosis and cardiovascular disease, the global leading cause of death. Aquaporins (AQPs) are membrane channels that facilitate water and glycerol transport across cellular membranes recently implicated in the homeostasis of the cardiovascular system. Apolipoprotein-E deficient (apoE−/−) mice are a common model to study the progression of atherosclerosis. Nevertheless, the pattern of expression of AQPs in this atheroprone model is poorly characterized. In this study, apoE−/− mice were fed an atherogenic high-fat (HF) or a control diet. Plasma was collected at multiple time points to assess metabolic disturbances. At the endpoint, the aortic atherosclerotic burden was quantified using high field magnetic resonance imaging. Moreover, the transcriptional levels of several AQP isoforms were evaluated in the liver, white adipocyte tissue (WAT), and brown adipocyte tissue (BAT). The results revealed that HF-fed mice, when compared to controls, presented an exacerbated systemic inflammation and atherosclerotic phenotype, with no major differences in systemic methylation status, circulating amino acids, or plasma total glutathione. Moreover, an overexpression of the isoform AQP5 was detected in all studied tissues from HF-fed mice when compared to controls. These results suggest a novel role for AQP5 on diet-induced atherosclerosis that warrants further investigation.

A very-low carbohydrate content in a high-fat diet modifies the plasma metabolome and alleviates experimental atherosclerosis

“…The effect of the experimental diets used in this study on the systemic methylation index, the plasma adenosylmethionine to adenosylhomocysteine ratio, has been previously evaluated in ApoE —/— mice 16,17 . A significantly decreased plasma AdoMet:AdoHcy ratio was detected in KD-fed mice but not in HF-fed mice, versus controls, thus suggesting the existence of systemic hypomethylation under nutritional ketosis.…”

“…After 12 weeks, mice were euthanized by carbon dioxide inhalation and aortas were collected, as previously described in detail [16][17][18] . Briefly, aortas were perfused with 10 mL of cold phosphate saline buffer (PBS), followed by 10% neutral buffered formalin (NBF) in PBS, and were then fixed overnight in 10% NBF.…”

“…The copyright holder for this preprint this version posted February 7, 2023. ; https://doi.org/10.1101/2023.02.07.527515 doi: bioRxiv preprint and next transferred into glass tubes (6 mm OD, 4 mm ID and 60 mm length) for magnetic resonance imaging (MRI) analysis. Aortic plaque burden was then quantified using an Agilent 14T micro imaging system, as previously described in detail [16][17][18] . A gradient echo imaging sequence with an imaging time of 9 h 48 min was used to generate 3D datasets of the aortas.…”

Diet-Induced Severe Hyperhomocysteinemia Promotes Atherosclerosis Progression and Dysregulates the Plasma Metabolome in Apolipoprotein-E-Deficient Mice

“…The aortas were exposed and isolated, and approximately half of the abdominal aorta was excised, immediately immersed into liquid nitrogen, and stored at −80 • C until further analysis was undertaken. The remainder of each aorta, after double perfusion (10 mL PBS followed by 10 mL neutral buffered formalin 10% (NBF, Fisher Chemical), was fixed in NBF for 24 h, and then transferred to PBS, as previously described in detail [19][20][21][22][23].…”

A Hypomethylating Ketogenic Diet in Apolipoprotein E-Deficient Mice: A Pilot Study on Vascular Effects and Specific Epigenetic Changes

“…Aortas were equilibrated in a solution of 0.1% Magnevist (Bayer, Whippany, NJ, USA), 0.25% sodium azide in PBS overnight at 4 • C, then placed into glass tubes (6 mm OD, 4 mm ID and 60 mm length) for MRI analysis. Aortic plaque burden was then quantified using an Agilent 14T micro imaging system, as previously described in detail [13,48]. A gradient echo imaging sequence with an imaging time of 9 h 48 min was used to generate 3D datasets of the aortas [49].…”