scholarly journals Mineralocorticoid and Estrogen Receptors in Endothelial Cells Coordinately Regulate Microvascular Function in Obese Female Mice

Hypertension ◽  
2021 ◽  
Author(s):  
Lauren A. Biwer ◽  
Brigett V. Carvajal ◽  
Qing Lu ◽  
Joshua J. Man ◽  
Iris Z. Jaffe
Keyword(s):  
Endothelial Cells ◽  
High Fat Diet ◽  
Ex Vivo ◽  
Microvascular Dysfunction ◽  
Estrogen Receptor Α ◽  
No Synthase ◽  
Wild Type ◽  
High Fat ◽  
Obese Female

Obesity impairs endothelial-mediated vasodilation, the earliest step in vascular disease and a contributor to hypertension. We previously demonstrated that endothelial cell MR (mineralocorticoid receptor) deletion prevents obesity-induced microvascular dysfunction in females by increasing nitric oxide (NO)-mediated vasodilation. ERα (Estrogen receptor α) can oppose MR function, therefore, we hypothesized that ERα mediates the benefits of endothelial MR deficiency. Females lacking endothelial MR or wild-type littermates were fed control or high-fat diet for 20 weeks to cause obesity. MR deletion improved mesenteric artery endothelial-dependent vasodilation in obese females, and ex vivo ERα inhibition negated this protective effect. Endothelial MR deletion resulted in significantly more ERα mRNA and protein. In vitro, estrogen increased endothelial NO synthase phosphorylation, and this was inhibited by aldosterone and dependent on MR. Both proteins coimmunoprecipitated with striatin and a mimetic peptide that disrupts ERα-striatin binding also decreased MR-striatin interaction. Finally, removing endothelial MR in obese females restored endothelial function by increasing the NO component of vasodilation. Combined deletion of endothelial ERα negated the benefit of endothelial MR deletion. These results indicate that endothelial ERα prevents the detrimental effects of MR in obesity by increasing NO to rescue vasodilation in females. MR and ERα may compete for striatin binding within endothelial cells to regulate NO. These data identify a novel mechanism that promotes MR antagonism to prevent obesity-induced microvascular dysfunction in females.

scholarly journals Palmitoleic Acid (N-7) Attenuates the Immunometabolic Disturbances Caused by a High-Fat Diet Independently of PPARα

2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Camila O. Souza ◽  
Alexandre A. S. Teixeira ◽  
Edson A. Lima ◽  
Helena A. P. Batatinha ◽  
Lara M. Gomes ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Oleic Acid ◽  
High Fat Diet ◽  
Palmitoleic Acid ◽  
Serum Levels ◽  
Standard Diet ◽  
Liver Inflammation ◽  
Wild Type ◽  
High Fat

Palmitoleic acid (PMA) has anti-inflammatory and antidiabetic activities. Here we tested whether these effects of PMA on glucose homeostasis and liver inflammation, in mice fed with high-fat diet (HFD), are PPAR-αdependent. C57BL6 wild-type (WT) and PPAR-α-knockout (KO) mice fed with a standard diet (SD) or HFD for 12 weeks were treated after the 10th week with oleic acid (OLA, 300 mg/kg of b.w.) or PMA 300 mg/kg of b.w. Steatosis induced by HFD was associated with liver inflammation only in the KO mice, as shown by the increased hepatic levels of IL1-beta, IL-12, and TNF-α; however, the HFD increased the expression of TLR4 and decreased the expression of IL1-Ra in both genotypes. Treatment with palmitoleate markedly attenuated the insulin resistance induced by the HFD, increased glucose uptake and incorporation into muscle in vitro, reduced the serum levels of AST in WT mice, decreased the hepatic levels of IL1-beta and IL-12 in KO mice, reduced the expression of TLR-4 and increased the expression of IL-1Ra in WT mice, and reduced the phosphorylation of NF𝜅B (p65) in the livers of KO mice. We conclude that palmitoleate attenuates diet-induced insulin resistance, liver inflammation, and damage through mechanisms that do not depend on PPAR-α.

scholarly journals Endothelial ADAM17 Expression in the Progression of Kidney Injury in an Obese Mouse Model of Pre-Diabetes

2021 ◽  
Vol 23 (1) ◽  
pp. 221
Author(s):  
Vanesa Palau ◽  
Josué Jarrín ◽  
Sofia Villanueva ◽  
David Benito ◽  
Eva Márquez ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Mouse Model ◽  
High Fat Diet ◽  
Macrophage Infiltration ◽  
Creatinine Ratio ◽  
Wild Type ◽  
High Fat ◽  
Tnf Α ◽  
Galectin 3 ◽  
Factor Α

Disintegrin and metalloproteinase domain 17 (ADAM17) activates inflammatory and fibrotic processes through the shedding of various molecules such as Tumor Necrosis Factor-α (TNF-α) or Transforming Growht Factor-α (TGF-α). There is a well-recognised link between TNF-α, obesity, inflammation, and diabetes. In physiological situations, ADAM17 is expressed mainly in the distal tubular cell while, in renal damage, its expression increases throughout the kidney including the endothelium. The aim of this study was to characterize, for the first time, an experimental mouse model fed a high-fat diet (HFD) with a specific deletion of Adam17 in endothelial cells and to analyse the effects on different renal structures. Endothelial Adam17 knockout male mice and their controls were fed a high-fat diet, to induce obesity, or standard rodent chow, for 22 weeks. Glucose tolerance, urinary albumin-to-creatinine ratio, renal histology, macrophage infiltration, and galectin-3 levels were evaluated. Results showed that obese mice presented higher blood glucose levels, dysregulated glucose homeostasis, and higher body weight compared to control mice. In addition, obese wild-type mice presented an increased albumin-to-creatinine ratio; greater glomerular size and mesangial matrix expansion; and tubular fibrosis with increased galectin-3 expression. Adam17 deletion decreased the albumin-to-creatinine ratio, glomerular mesangial index, and tubular galectin-3 expression. Moreover, macrophage infiltration in the glomeruli of obese Adam17 knockout mice was reduced as compared to obese wild-type mice. In conclusion, the expression of ADAM17 in endothelial cells impacted renal inflammation, modulating the renal function and histology in an obese pre-diabetic mouse model.

Abstract 462: Expression, Phosphorylation and Interaction Partners of the Transcription Factor Grainyhead-like 3 in the Endothelium

2017 ◽  
Vol 37 (suppl_1) ◽  
Author(s):  
Stefanie Kohlgrüber ◽  
Nadine Dyballa-Rukes ◽  
Sabine Metzger ◽  
Anh Nguyen ◽  
Jim Garmey ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Transcription Factor ◽  
High Fat Diet ◽  
Ex Vivo ◽  
Src Kinase ◽  
Potential Interaction ◽  
Regulation Of Transcription ◽  
High Fat ◽  
Interaction Partners ◽  
The Impact

The transcription factor Grainyhead-like 3 (GRHL3) regulates apoptosis, migration and NO-bioavailability and thus, critical functions of endothelial cell, which are impaired in many cardiovascular diseases. However, due to the lack of a good antibody, all experiments concerning the regulation of GRHL3 itself were performed on the RNA level. After establishing a new antibody, we analyzed the GRHL3 protein in aortic sections of ApoE-deficient mice fed a high fat diet, a model for atherosclerosis. The diet resulted in a reduction of GRHL3 levels in the endothelium, which was corroborated ex vivo in endothelial cells treated with LDL. This simulated high fat diet also led to a decrease in endothelial NO-synthase. As the activity of transcription factors is regulated by post-translational modifications and protein-protein interactions, we analyzed the phosphorylation of GRHL3 and identified potential interaction partners. Using a combination of immunoprecipitation and -blotting we demonstrated for the first time that GRHL3 is phosphorylated on tyrosine residues. Furthermore, this phosphorylation was NO-inducible and Src-kinase-dependent. After characterization of the modified residues, we will assess their relevance by determining the impact of phospho-mimetic and non-phosphorylatable mutants on functional parameters of endothelial cells. To identify potential interaction partners of GRHL3 we immunoprecipitated the protein and analyzed the co-precipitated proteins by mass spectrometry. We identified the DBHS-proteins NONO and SFPQ, which have been implicated in the regulation of transcription and alternative splicing. The interaction with these two proteins was validated by co-immunoprecipitation. As a next step, we will overexpress and downregulate these proteins in endothelial cells to evaluate their cross-talk with GRHL3. Taken together our findings demonstrate (i) a downregulation of GRHL3 in a disease setting, (ii) a Src-kinase dependent, NO-inducible phosphorylation and (iii) an interaction with other gene-regulatory proteins. The analysis of the functional consequences of these different aspects of GRHL3 regulation will further shed light on the GRHL3 network in the endothelium and thus, its functions in the vasculature.

scholarly journals Blockade of Sphingosine 1-Phosphate Receptor 2 Signaling Attenuates High-Fat Diet-Induced Adipocyte Hypertrophy and Systemic Glucose Intolerance in Mice

Endocrinology ◽  
2016 ◽  
Vol 157 (5) ◽  
pp. 1839-1851 ◽  
Author(s):  
Yoshihiko Kitada ◽  
Kazuo Kajita ◽  
Koichiro Taguchi ◽  
Ichiro Mori ◽  
Masahiro Yamauchi ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
High Fat Diet ◽  
Adipogenic Differentiation ◽  
Nuclear Antigen ◽  
Wild Type ◽  
High Fat ◽  
Insulin Tolerance ◽  
Sphingosine 1 Phosphate

Abstract Sphingosine 1-phosphate (S1P) is known to regulate insulin resistance in hepatocytes, skeletal muscle cells, and pancreatic β-cells. Among its 5 cognate receptors (S1pr1–S1pr5), S1P seems to counteract insulin signaling and confer insulin resistance via S1pr2 in these cells. S1P may also regulate insulin resistance in adipocytes, but the S1pr subtype(s) involved remains unknown. Here, we investigated systemic glucose/insulin tolerance and phenotypes of epididymal adipocytes in high-fat diet (HFD)-fed wild-type and S1pr2-deficient (S1pr2−/−) mice. Adult S1pr2−/− mice displayed smaller body/epididymal fat tissue weights, but the differences became negligible after 4 weeks with HFD. However, HFD-fed S1pr2−/− mice displayed better scores in glucose/insulin tolerance tests and had smaller epididymal adipocytes that expressed higher levels of proliferating cell nuclear antigen than wild-type mice. Next, proliferation/differentiation of 3T3-L1 and 3T3-F442A preadipocytes were examined in the presence of various S1pr antagonists: JTE-013 (S1pr2 antagonist), VPC-23019 (S1pr1/S1pr3 antagonist), and CYM-50358 (S1pr4 antagonist). S1P or JTE-013 treatment of 3T3-L1 preadipocytes potently activated their proliferation and Erk phosphorylation, whereas VPC-23019 inhibited both of these processes, and CYM-50358 had no effects. In contrast, S1P or JTE-013 treatment inhibited adipogenic differentiation of 3T3-F442A preadipocytes, whereas VPC-23019 activated it. The small interfering RNA knockdown of S1pr2 promoted proliferation and inhibited differentiation of 3T3-F442A preadipocytes, whereas that of S1pr1 acted oppositely. Moreover, oral JTE-013 administration improved glucose tolerance/insulin sensitivity in ob/ob mice. Taken together, S1pr2 blockade induced proliferation but suppressed differentiation of (pre)adipocytes both in vivo and in vitro, highlighting a novel therapeutic approach for obesity/type 2 diabetes.

IL-1R and MyD88 signalling in CD4+ T cells promote Th17 immunity and atherosclerosis

2017 ◽  
Vol 114 (1) ◽  
pp. 180-187 ◽  
Author(s):  
Daniel Engelbertsen ◽  
Sara Rattik ◽  
Maria Wigren ◽  
Jenifer Vallejo ◽  
Goran Marinkovic ◽  
...  
Keyword(s):  
T Cells ◽  
High Fat Diet ◽  
Cd4 T Cells ◽  
Wild Type ◽  
T Helper ◽  
High Fat ◽  
Lesion Development ◽  
Ifn Γ

Abstract Aims The role of CD4+ T cells in atherosclerosis has been shown to be dependent on cytokine cues that regulate lineage commitment into mature T helper sub-sets. In this study, we tested the roles of IL-1R1 and MyD88 signalling in CD4+ T cells in atherosclerosis. Methods and results We transferred apoe-/-myd88+/+ or apoe-/-myd88-/- CD4+ T cells to T- and B-cell-deficient rag1-/-apoe-/- mice fed high fat diet. Mice given apoe-/-myd88-/- CD4+ T cells exhibited reduced atherosclerosis compared with mice given apoe-/-myd88+/+ CD4+ T cells. CD4+ T cells from apoe-/-myd88-/- produced less IL-17 but similar levels of IFN-γ. Treatment of human CD4+ T cells with a MyD88 inhibitor inhibited IL-17 secretion in vitro. Transfer of il1r1-/- CD4+ T cells recapitulated the phenotype seen by transfer of myd88-/- CD4+ T cells with reduced lesion development and a reduction in Th17 and IL-17 production compared with wild type CD4+ T cell recipients. Relative collagen content of lesions was reduced in mice receiving il1r1-/- CD4+ T cells. Conclusion We demonstrate that both IL1R and MyD88 signalling in CD4+ T cells promote Th17 immunity, plaque growth and may regulate plaque collagen levels.

scholarly journals Pyrogallol-Phloroglucinol-6 6-Bieckol on Attenuates High-Fat Diet-Induced Hypertension by Modulating Endothelial-to-Mesenchymal Transition in the Aorta of Mice

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Myeongjoo Son ◽  
Seyeon Oh ◽  
Ji Tae Jang ◽  
Kuk Hui Son ◽  
Kyunghee Byun
Keyword(s):  
Endothelial Cells ◽  
High Fat Diet ◽  
Oxidized Ldl ◽  
Intima Media Thickness ◽  
Mesenchymal Cell ◽  
High Fat ◽  
Mesenchymal Transition ◽  
Induced Hypertension ◽  
Endothelial To Mesenchymal Transition

Endothelial-to-mesenchymal transition (EndMT), which is involved in the development of various cardiovascular diseases, is induced by dyslipidemia or obesity. In dyslipidemia, the increased levels of oxidized low-density lipoproteins (oxLDL) upregulated the lectin-type oxidized LDL receptor 1 (Lox-1), which then upregulated the down signaling pathways of PKC-α/MMPs/TGF-β/SMAD2 or 3 and increased the EndMT. In this study, we investigated the effect of pyrogallol-phloroglucinol-6,6-bieckol (PPB), which is a compound of Ecklonia cava (E. cava), on decreased blood pressure (BP) by attenuating the EndMT in a high-fat diet- (HFD-) fed animal model. We also investigated PPB’s attenuation effect on EndMT in oxLDL-treated mouse endothelial cells as an in vitro model. The results indicated that, in the aorta or endothelial cells of mice, the HFD or oxLDL treatment significantly increased the expression of Lox-1/PKC-α/MMP9/TGF-β/SMAD2/SMAD3. The PPB treatment significantly decreased its expression. In contrast, the HFD or oxLDL treatment significantly decreased the expression of the EC markers (PECAM-1 and vWF) while the PPB treatment significantly increased them. Moreover, the HFD or oxLDL treatment significantly increased the expression of the mesenchymal cell markers (α-SMA and vimentin) while PPB treatment significantly decreased them. PPB decreased the intima-media thickness and extracellular matrix amount of the aorta and attenuated the BP, which was increased by the HFD. In conclusion, PPB attenuated the upregulation of Lox-1/PKC-α/MMP9/TGF-β/SMAD2 and 3 and restored the EndMT in HFD-fed animals. Moreover, PPB showed a restoring effect on HFD-induced hypertension.

scholarly journals Extracellular vesicle release and uptake by the liver under normo- and hyperlipidemia

2021 ◽  
Author(s):  
Krisztina Németh ◽  
Zoltán Varga ◽  
Dorina Lenzinger ◽  
Tamás Visnovitz ◽  
Anna Koncz ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Kupffer Cells ◽  
Liver Cell ◽  
High Fat Diet ◽  
Cell Types ◽  
Extracellular Vesicle ◽  
High Fat ◽  
Liver Sinusoidal Endothelial Cells ◽  
Sinusoidal Endothelial Cells

AbstractLiver plays a central role in elimination of circulating extracellular vesicles (EVs), and it also significantly contributes to EV release. However, the involvement of the different liver cell populations remains unknown. Here, we investigated EV uptake and release both in normolipemia and hyperlipidemia. C57BL/6 mice were kept on high fat diet for 20–30 weeks before circulating EV profiles were determined. In addition, control mice were intravenously injected with 99mTc-HYNIC-Duramycin labeled EVs, and an hour later, biodistribution was analyzed by SPECT/CT. In vitro, isolated liver cell types were tested for EV release and uptake with/without prior fatty acid treatment. We detected an elevated circulating EV number after the high fat diet. To clarify the differential involvement of liver cell types, we carried out in vitro experiments. We found an increased release of EVs by primary hepatocytes at concentrations of fatty acids comparable to what is characteristic for hyperlipidemia. When investigating EV biodistribution with 99mTc-labeled EVs, we detected EV accumulation primarily in the liver upon intravenous injection of mice with medium (326.3 ± 19.8 nm) and small EVs (130.5 ± 5.8 nm). In vitro, we found that medium and small EVs were preferentially taken up by Kupffer cells, and liver sinusoidal endothelial cells, respectively. Finally, we demonstrated that in hyperlipidemia, there was a decreased EV uptake both by Kupffer cells and liver sinusoidal endothelial cells. Our data suggest that hyperlipidema increases the release and reduces the uptake of EVs by liver cells. We also provide evidence for a size-dependent differential EV uptake by the different cell types of the liver. The EV radiolabeling protocol using 99mTc-Duramycin may provide a fast and simple labeling approach for SPECT/CT imaging of EVs biodistribution.

scholarly journals Sympathetic cardiac hyperinnervation and atrial autonomic imbalance in diet-induced obesity promote cardiac arrhythmias

2013 ◽  
Vol 305 (10) ◽  
pp. H1530-H1537 ◽  
Author(s):  
Belinda H. McCully ◽  
Wohaib Hasan ◽  
Cole T. Streiff ◽  
Jennifer C. Houle ◽  
William R. Woodward ◽  
...  
Keyword(s):  
High Fat Diet ◽  
Parasympathetic Nervous System ◽  
Ex Vivo ◽  
System Control ◽  
Sprague Dawley ◽  
High Fat ◽  
Sprague Dawley Rats ◽  
Normal Chow

Obesity increases the risk of arrhythmias and sudden cardiac death, but the mechanisms are unknown. This study tested the hypothesis that obesity-induced cardiac sympathetic outgrowth and hyperinnervation promotes the development of arrhythmic events. Male Sprague-Dawley rats (250–275 g), fed a high-fat diet (33% kcal/fat), diverged into obesity-resistant (OR) and obesity-prone (OP) groups and were compared with rats fed normal chow (13% kcal/fat; CON). In vitro experiments showed that both OR and OP rats exhibited hyperinnervation of the heart and high sympathetic outgrowth compared with CON rats, even though OR rats are not obese. Despite the hyperinnervation and outgrowth, we showed that, in vivo, OR rats were less susceptible to arrhythmic events after an intravenous epinephrine challenge compared with OP rats. On examining total and stimulus-evoked neurotransmitter levels in an ex vivo system, we demonstrate that atrial acetylcholine content and release were attenuated in OP compared with OR and CON groups. OP rats also expressed elevated atrial norepinephrine content, while norepinephrine release was suppressed. These findings suggest that the consumption of a high-fat diet, even in the absence of overt obesity, stimulates sympathetic outgrowth and hyperinnervation of the heart. However, normalized cardiac parasympathetic nervous system control may protect the heart from arrhythmic events.

Abstract 14050: The Gut Flora Promotes Endothelial Dysfunction Through Vascular MicroRNA-204-mediated Down-regulation of Endothelial Sirtuin1

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Ajit Vikram ◽  
Young-Rae Kim ◽  
Santosh Kumar ◽  
Julia S Jacobs ◽  
Kaikobad Irani
Keyword(s):  
Endothelial Cells ◽  
Endothelial Dysfunction ◽  
Endothelial Function ◽  
High Fat Diet ◽  
Ex Vivo ◽  
Vascular Wall ◽  
High Fat ◽  
Gut Flora ◽  
Atherosclerotic Vascular Disease ◽  
Germ Free

The gut flora contributes to development of atherosclerosis. Endothelial dysfunction, one manifestation of which is impaired endothelium-dependent vasorelaxation, accompanies and promotes atherosclerotic vascular disease. Here we show that gut flora impair endothelium-dependent vasorelaxation by remotely up-regulating microRNA-204 (miR-204) which downregulates SIRTUIN1 (SIRT1) in the vascular wall. Microarray analysis in aortas of germ-free mice revealed a set of down-regulated microRNAs, including miR-204, which target SIRT1. Suppression of gut flora in mice with antibiotics in drinking water decreased aortic miR-204, increased aortic SIRT1, and improved endothelium-dependent vasorelaxation, effects that were reversed with discontinuation of antibiotics. In addition, miR-204 mimic impaired endothelium-dependent aortic vasorelaxation ex vivo. Moreover, high-fat diet feeding stimulated aortic miR-204, suppressed SIRT1, and impaired endothelial function, all of which were mitigated by administration of antibiotics, and reversed with stoppage of antibiotics. In contrast, antibiotics did not improve high-fat diet-induced endothelial dysfunction in mice conditionally lacking endothelial SIRT1. In addition, anti-miR-204 delivered systemically prevented high-fat diet-induced endothelial dysfunction and vascular SIRT1 decrease. Finally, serum from mice on antibiotics suppressed miR-204, and increased SIRT1, in endothelial cells, effects that were not observed with serum from mice in which antibiotics were discontinued. Therefore, the gut flora remotely downregulates endothelial SIRT1 through miR-204, leading to impairment of endothelial function.

scholarly journals Ghrelin Stimulates Endothelial Cells Angiogenesis through Extracellular Regulated Protein Kinases (ERK) Signaling Pathway

2018 ◽  
Vol 19 (9) ◽  
pp. 2530 ◽  
Author(s):  
Jun Wang ◽  
Lin He ◽  
Bahetiyaer Huwatibieke ◽  
Lingchao Liu ◽  
He Lan ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Adipose Tissue ◽  
Signaling Pathway ◽  
White Adipose Tissue ◽  
High Fat Diet ◽  
Erk Signaling ◽  
Wild Type ◽  
High Fat ◽  
And Migration ◽  
Extracellular Regulated Protein Kinases

Adipose tissue is hyper-vascularized. Vessels in adipose tissue not only supply nutrients and oxygen to nourish adipocytes, but also provide cytokines that regulate mass and function of adipose tissue. Understanding the fundamental mechanisms how vessels modulate adipocyte functions would provide new therapeutic options for treatment of metabolic disease and obesity. In recent years, researches about ghrelin are focused on glucose and lipid metabolism, but its effect on vascular function remains uncharacterized. In the present study, ghrelin receptor gene deletion mice (Ghsr−/− mice) were used to study ghrelin-regulated vascular metabolism in white adipose tissue. Ghsr−/− mice demonstrated lower food intake, lower body weight, and resistance to high-fat diet-induced obesity. The number of vessels in white adipose tissue was decreased in Ghsr−/− mice when compared with wild type mice fed with high-fat diet. To further define ghrelin effects in vitro, we used endothelial progenitor cells from wild type and Ghsr−/− mice as well as human umbilical vein endothelial cells in our experiments. We found that ghrelin stimulated endothelial cells angiogenesis and migration through the MEK-ERK signaling pathway. [d-Lys3]-GHRP-6 and PD98059 could reverse the effects of ghrelin on endothelial cells. Our study indicates that ghrelin activates its receptor on endothelial cells to promote angiogenesis and migration via a mechanism involving the extracellular regulated protein kinases (ERK) signaling pathway.

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