scholarly journals Chronic NaHS Treatment Is Vasoprotective in High-Fat-Fed ApoE−/−Mice

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Asha Ford ◽  
Mohammad Al-Magableh ◽  
Tracey A. Gaspari ◽  
Joanne L. Hart
Keyword(s):  
High Fat Diet ◽  
Vascular Function ◽  
Vascular Dysfunction ◽  
Atherosclerotic Lesion ◽  
Vascular Changes ◽  
High Fat ◽  
Superoxide Generation ◽  
Atherosclerotic Lesions ◽  
Atherosclerotic Lesion Development

Hydrogen sulfide is emerging as an important mediator of vascular function that has antioxidant and cytoprotective effects. The aim of this study was to investigate the role of endogenous H2S and the effect of chronic exogenous H2S treatment on vascular function during the progression of atherosclerotic disease. ApoE−/−mice were fed a high-fat diet for 16 weeks and treated with the H2S donor NaHS or the cystathionine-γ-lyase (CSE) inhibitor D,L-propargylglycine (PPG), to inhibit endogenous H2S production for the final 4 weeks. Fat-fed ApoE−/−mice displayed significant aortic atherosclerotic lesions and significantly impaired endothelial function compared to wild-type mice. Importantly, 4 weeks of NaHS treatment significantly reduced vascular dysfunction and inhibited vascular superoxide generation. NaHS treatment significantly reduced the area of aortic atherosclerotic lesions and attenuated systolic blood pressure. Interestingly, inhibiting endogenous, CSE-dependent H2S production with PPG did not exacerbate the deleterious vascular changes seen in the untreated fat-fed ApoE−/−mice. The results indicate NaHS can improve vascular function by reducing vascular superoxide generation and impairing atherosclerotic lesion development. Endogenous H2S production via CSE is insufficient to counter the atherogenic effects seen in this model; however exogenous H2S treatment has a significant vasoprotective effect.

scholarly journals Androgen Receptor-Dependent and Independent Atheroprotection by Testosterone in Male Mice

Endocrinology ◽  
2010 ◽  
Vol 151 (11) ◽  
pp. 5428-5437 ◽  
Author(s):  
Johan Bourghardt ◽  
Anna S. K. Wilhelmson ◽  
Camilla Alexanderson ◽  
Karel De Gendt ◽  
Guido Verhoeven ◽  
...  
Keyword(s):  
Androgen Receptor ◽  
Apolipoprotein E ◽  
High Fat Diet ◽  
Atherosclerotic Lesion ◽  
Male Mice ◽  
Wild Type ◽  
High Fat ◽  
Lesion Area ◽  
Major Pathway

The atheroprotective effect of testosterone is thought to require aromatization of testosterone to estradiol, but no study has adequately addressed the role of the androgen receptor (AR), the major pathway for the physiological effects of testosterone. We used AR knockout (ARKO) mice on apolipoprotein E-deficient background to study the role of the AR in testosterone atheroprotection in male mice. Because ARKO mice are testosterone deficient, we sham operated or orchiectomized (Orx) the mice before puberty, and Orx mice were supplemented with placebo or a physiological testosterone dose. From 8 to 16 wk of age, the mice consumed a high-fat diet. In the aortic root, ARKO mice showed increased atherosclerotic lesion area (+80%, P < 0.05). Compared with placebo, testosterone reduced lesion area both in Orx wild-type (WT) mice (by 50%, P < 0.001) and ARKO mice (by 24%, P < 0.05). However, lesion area was larger in testosterone-supplemented ARKO compared with testosterone-supplemented WT mice (+57%, P < 0.05). In WT mice, testosterone reduced the presence of a necrotic core in the plaque (80% among placebo-treated vs. 12% among testosterone-treated mice; P < 0.05), whereas there was no significant effect in ARKO mice (P = 0.20). In conclusion, ARKO mice on apolipoprotein E-deficient background display accelerated atherosclerosis. Testosterone treatment reduced atherosclerosis in both WT and ARKO mice. However, the effect on lesion area and complexity was more pronounced in WT than in ARKO mice, and lesion area was larger in ARKO mice even after testosterone supplementation. These results are consistent with an AR-dependent as well as an AR-independent component of testosterone atheroprotection in male mice.

Platelet P-selectin facilitates atherosclerotic lesion development

Blood ◽  
2003 ◽  
Vol 101 (7) ◽  
pp. 2661-2666 ◽  
Author(s):  
Peter C. Burger ◽  
Denisa D. Wagner
Keyword(s):  
Atherosclerotic Lesion ◽  
Soluble Form ◽  
Wild Type ◽  
Lesion Development ◽  
Atherosclerotic Lesions ◽  
Lesion Growth ◽  
Microparticle Formation ◽  
Apoe Deficient Mouse ◽  
Atherosclerotic Lesion Development

P-selectin is an adhesion molecule expressed on activated platelets and endothelium. It is known to play an important role in atherosclerosis. P-selectin also circulates in plasma in a soluble form (sP-selectin), which induces procoagulant microparticle formation. We investigated the role of platelet versus endothelial P-selectin in generating sP-selectin and in the formation of atherosclerotic lesions in the apolipoprotein E (apoE)–deficient mouse model. For this we transplanted apoE−/−P-selectin−/− and apoE−/−P-selectin+/+ lethally irradiated mice with bone marrow of either genotype. Seven months after transplantation, we determined from the chimeric animals that the majority of circulating sP-selectin was of endothelial origin. Thus, in atherosclerosis, the procoagulant sP-selectin reflects endothelial rather than platelet activation. We found that endothelial P-selectin was crucial for the promotion of atherosclerotic lesion growth because in its absence only relatively small lesions developed. However, platelet P-selectin also contributed to the lesion development because lesions in wild-type recipients receiving transplants with wild-type platelets were 30% larger than those receiving P-selectin-deficient platelets (P < .008) and were more frequently calcified (80% versus 44%). In comparison with P-selectin wild-type animals, absence of either endothelial or platelet P-selectin inhibited migration of smooth muscle cells into the lesion. Thus, in addition to endothelium, platelets and their P-selectin also actively promote advanced atherosclerotic lesion development.

scholarly journals Unacylated Ghrelin Improves Vascular Dysfunction and Attenuates Atherosclerosis during High-Fat Diet Consumption in Rodents

2019 ◽  
Vol 20 (3) ◽  
pp. 499 ◽  
Author(s):  
Michela Zanetti ◽  
Gianluca Gortan Cappellari ◽  
Andrea Graziani ◽  
Rocco Barazzoni
Keyword(s):  
Oxidative Stress ◽  
Lipid Accumulation ◽  
High Fat Diet ◽  
Vascular Function ◽  
Vascular Dysfunction ◽  
High Fat ◽  
Enos Expression ◽  
Unacylated Ghrelin ◽  
Vascular Oxidative Stress ◽  
Expression And Activity

Unacylated ghrelin (UnGhr) exerts several beneficial actions on vascular function. The aim of this study was to assess the effects of UnGhr on high-fat induced endothelial dysfunction and its underlying mechanisms. Thoracic aortas from transgenic mice, which were overexpressing UnGhr and being control fed either a standard control diet (CD) or a high-fat diet (HFD) for 16 weeks, were harvested and used for the assessment of vascular reactivity, endothelial nitric oxide synthase (eNOS) expression and activity, thiobarbituric acid reactive substances (TBARS) and glutathione levels, and aortic lipid accumulation by Oil Red O staining. Relaxations due to acetylcholine and to DEA-NONOate were reduced (p < 0.05) in the HFD control aortas compared to vessels from the CD animals. Overexpression of UnGhr prevented HFD-induced vascular dysfunction, while eNOS expression and activity were similar in all vessels. HFD-induced vascular oxidative stress was demonstrated by increased (p < 0.05) aortic TBARS and glutathione in wild type (Wt) mice; however, this was not seen in UnGhr mice. Moreover, increased (p < 0.05) HFD-induced lipid accumulation in vessels from Wt mice was prevented by UnGhr overexpression. In conclusion, chronic UnGhr overexpression results in improved vascular function and reduced plaque formation through decreased vascular oxidative stress, without affecting the eNOS pathway. This research may provide new insight into the mechanisms underlying the beneficial effects of UnGhr on the vascular dysfunction associated with obesity and the metabolic syndrome.

Abstract 61: Adipose Tissue Specific HO-1 Induction Regulates the Crosstalk between Wnt and β-catenin Pathways and Leads to Restoration of Vascular Endothelial Function in Mice Fed a High Fat Diet

Hypertension ◽  
2012 ◽  
Vol 60 (suppl_1) ◽  
Author(s):  
Jian Cao ◽  
Stephen J Peterson ◽  
Michal L Schwartzman ◽  
Komal Sodhi ◽  
Rita Rezzani ◽  
...  
Keyword(s):  
Insulin Sensitivity ◽  
Inflammatory Cytokines ◽  
High Fat Diet ◽  
Vascular Function ◽  
Vascular Dysfunction ◽  
Subcutaneous Fat ◽  
Heme Oxygenase 1 ◽  
High Fat ◽  
Diet Induced Obesity ◽  
Intracardiac Injection

The principal goal of the present study is to examine the contributions of adipocyte specific over expression of the cytoprotective gene heme oxygenase-1 (HO-1) in modulating vascular function in an animal model of diet induced obesity. A lentiviral construct of the human HO-1 was synthesized under the control of an aP2-activated promoter so as to ensure HO-1 targeting to murine adipocytes. Lentiviruses (50 μl, 2x109 TU/ml in saline) were injected into the C57BL/6 mice by a single intracardiac injection. Mice (6-7 wks old) were divided into 4 groups: Control, high fat diet (HF) mice receiving the control Lenti-aP2-GFP (HF-GFP) and high fat diet mice receiving the lenti-aP2-HO-1 (HF-HO-1) with and without treatment with SnMP. Transduction of lenti-aP2-HO-1 increased human HO-1 expression in adipose tissues without affecting endogenous mice HO-1 (p<0.01). In mice fed a HF diet, lenti-aP2-HO-1 transduction attenuated the increases in body weight (from 52.0±1.0 g to 35.6±2.1g; p<0.01), blood glucose (from 255±3.5 g to 140±2.9mg/dl), blood pressure (from 135±2.8mmHg to 101±2.2mmHg; p<0.01) and inflammatory cytokines as well as the content of both visceral (from 5.5±0.15g to 2.9±0.22g; p<0.05) and subcutaneous fat (p<0.05). Transduction of lenti-aP2-HO-1 increased the numbers of adipocytes of small cell size (p<0.05), insulin sensitivity (p<0.05), adiponectin levels (from 32.4±1.9μg/ml to 19.9±2.1μg/ml; p<0.05) as well as vascular relaxation to acetylcholine ( p<0.05) compared to HF mice administered the lenti-aP2- GFP. Adipocytes of mice fed a HF diet expressed high levels of PPARγ, aP2, C/EBP and Wnt5b proteins and displayed marked increases in Peg1/Mest (p<0.03). Lenti-aP2-HO-1 transduction lowered the elevated levels of these proteins and increased Shh, Wnt10b and β-catenin (p<0.05). Inhibition of HO activity by administration of tin mesoporphyrin (SnMP) to HF-fed mice transduced with the lenti-aP2-HO-1 reversed the decrease in Peg 1/Mest, TNFα and MCP-1 levels. This novel study demonstrate that adipocyte-specific overexpression of HO-1 attenuates HF-mediated adiposity and vascular dysfunction, increases insulin sensitivity and improves adipocyte function by increasing adiponectin, Shh and WNT10b and decreasing inflammatory cytokines.

Abstract 265: Platelet C-Type Lectinlike (CLEC)-2 Receptor Plays a Protective Role Against Development of Atherosclerosis in Atherosclerosis-Prone Mice

2014 ◽  
Vol 34 (suppl_1) ◽  
Author(s):  
Marie Lordkipanidze ◽  
Matthew J Harrison ◽  
Steve P Watson ◽  
G E Rainger
Keyword(s):  
High Fat Diet ◽  
Blood Lipid ◽  
Protective Role ◽  
Plaque Burden ◽  
Platelet Glycoprotein ◽  
High Fat ◽  
T Helper 17 ◽  
Platelet Surface ◽  
Atherosclerotic Lesions

Background: Platelets can influence progression of plaque formation by facilitating recruitment of inflammatory cells at the sites of atherosclerotic lesions. A C-type lectin-like receptor, CLEC-2, abundantly expressed on the platelet surface, has been shown to regulate lymphatic development in utero though an interaction with Podoplanin. Interestingly, lymphatic vasculature is increased in ischemic and inflamed hearts, and in cholesterol-rich atherosclerotic lesions. Moreover, Podoplanin expression is up-regulated on inflammatory macrophages and on T-helper 17 cells. However, the role of the Podoplanin - CLEC-2 interaction in atherosclerosis remains unknown. Aim: We sought to investigate the role of CLEC-2 on atherosclerotic development in ApoE-deficient mice. Methods: CreERT.CLEC-2fl/fl x ApoE-/- and litter-matched ApoE-/- mice were treated with tamoxifen at the age of 9 weeks and were put on a high-fat diet for 6 weeks. Animals were killed at the age of 16 weeks, when platelet function assays and atherosclerosis assays were carried out. Results: Expression of CLEC-2 was abolished in tamoxifen-treated CreERT.CLEC-2fl/fl x ApoE-/- mice (n=8), whereas normal levels were seen in ApoE-/- controls (n=10) also treated with tamoxifen. CreERT.CLEC-2fl/fl x ApoE-/- and ApoE-/- mice had similar baseline characteristics, comparable levels of platelet glycoprotein expression (GPIb, GPIIbIIIa and GPVI) and normal platelet responses to platelet agonists (collagen-related peptide, PAR-4 peptide, ADP and arachidonic acid). Blood lipid levels were comparable between CreERT.CLEC-2fl/fl x ApoE-/- and control animals. Atherosclerotic plaque burden was significantly higher in the aortas of CreERT.CLEC-2fl/fl x ApoE-/- mice fed a high-fat diet for 6 weeks compared with their ApoE-/- counterparts. The higher plaque burden was seen consistently throughout the aorta, but reached significance at the level of whole aorta, abdominal aorta, outer curvature and the left subclavian region. This was seen in both male and female animals. Conclusions: The platelet-borne CLEC-2 receptor appears to have a protective role against atherogenesis in atheroprone mice. Further research to investigate the underlying mechanisms is warranted.

scholarly journals Chlamydia pneumoniae and Hyperlipidemia Are Co-Risk Factors for Atherosclerosis: Infection Prior to Induction of Hyperlipidemia Does Not Accelerate Development of Atherosclerotic Lesions in C57BL/6J Mice

2002 ◽  
Vol 70 (9) ◽  
pp. 5332-5334 ◽  
Author(s):  
Erwin Blessing ◽  
Lee Ann Campbell ◽  
Michael E. Rosenfeld ◽  
Cho-chou Kuo
Keyword(s):  
Chlamydia Pneumoniae ◽  
Atherosclerotic Lesion ◽  
High Cholesterol Diet ◽  
Cholesterol Diet ◽  
High Cholesterol ◽  
High Fat ◽  
Lesion Development ◽  
Atherosclerotic Lesions ◽  
Accelerate Development ◽  
Atherosclerotic Lesion Development

ABSTRACT Chlamydia pneumoniae has been shown to accelerate atherosclerotic lesion development in hyperlipidemic animals. This study showed that C. pneumoniae did not accelerate lesion development in mice if a high-fat/high-cholesterol diet was started after infection, indicating that C. pneumoniae is a co-risk factor with hyperlipidemia for cardiovascular disease.

Abstract 183: Oxidized LDL Cholesterol Induces Endothelial Dysfunction in the Aorta and Lox-1 Expression in Macrophages

2012 ◽  
Vol 32 (suppl_1) ◽  
Author(s):  
Anja Leuner ◽  
David M Poitz ◽  
Robert Augustin ◽  
Heike Neubauer ◽  
Coy Brunssen ◽  
...  
Keyword(s):  
Endothelial Dysfunction ◽  
Endothelial Function ◽  
High Fat Diet ◽  
Ldl Cholesterol ◽  
Oxidized Ldl ◽  
High Fat ◽  
Human Macrophages ◽  
Atherosclerotic Lesions ◽  
The Impact

Elevated plasma cholesterol is one of the major risk factors in the development of atherosclerotic lesions. Oxidation of native LDL cholesterol (nLDL) by reactive oxygen species leads to the formation of oxidized LDL (oxLDL). An important receptor for the cellular uptake of oxLDL is the lectin-like oxidized low-density lipoprotein receptor-1 (Lox-1). Lox-1 is highly expressed on macrophages, but also present on arterial endothelial and vascular smooth muscle cells. Especially the uptake by macrophages leads to the formation of foam cells in atherosclerotic lesions. Aim of the present study was to analyze the impact of oxLDL on endothelial function in murine aortas and on Lox-1 expression in human macrophages. In addition, we analyzed the effect of a high-fat diet on vascular function in mice with an endothelial Lox-1 overexpression. First, we incubated aortic rings of wild-type mice for 2 h with 100 μg/mL oxLDL and analyzed the endothelial function using a Mulvany myograph. Compared to basal conditions, oxLDL significantly impaired endothelium-dependent vasodilation. Next, we fed mice with an endothelial overexpression of Lox-1 for 20 weeks a high-fat diet and analyzed the endothelial function in the thoracic aorta. Interestingly, these mice had no impaired endothelium-dependent relaxation after high-fat diet feeding. To get further insight into Lox-1 regulation by oxLDL, we analyzed the impact of oxLDL on Lox-1 expression in human macrophages. Monocytic THP-1 cells were differentiated with phorbol myristate acetate into macrophages and stimulated for 24 h with nLDL or oxLDL. We found a significant induction of Lox-1 mRNA expression after oxLDL incubation, whereas nLDL had no effect. Our data suggest an increased oxLDL uptake in oxLDL-treated macrophages by increased Lox-1 receptor expression. In conclusion, our data support an important role of oxLDL as a proatherosclerotic risk factor by its ability to induce endothelial dysfunction and Lox-1 expression in macrophages. Both processes may be involved in the development of atherosclerotic lesions but the physiological significance and functional role of Lox-1 in contributing to the human disease warrants further investigations.

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