scholarly journals Evolution of angiotensin II-mediated atherosclerosis in ApoE KO mice

2010 ◽  
Vol 3 (4) ◽  
Author(s):  
Niedzwiecki
Keyword(s):  
2008 ◽  
Vol 294 (1) ◽  
pp. F120-F129 ◽  
Author(s):  
Frédéric Michel ◽  
Serge Simonet ◽  
Christine Vayssettes-Courchay ◽  
Florence Bertin ◽  
Patricia Sansilvestri-Morel ◽  
...  

Early manifestations of kidney disease occur in atherosclerosis and activation of TP (thromboxane A2) receptors is implicated in atherosclerotic, diabetes, and renal diseases. The purpose of the present study was to analyze, in isolated, perfused mouse kidneys, the participation of TP receptors in renal vasoconstrictions and vasodilatations. In kidneys, taken from wild-type C57BL6, apolipoprotein E-deficient (ApoE-KO) and diabetic ApoE-KO mice, changes in perfusion pressure were recorded. Constrictions to TP receptor ligands U 46619, arachidonic acid, PGH2, and 8-iso-PGF2α, but not those to angiotensin II, endothelin, or norepinephrine, were inhibited by the selective TP receptor antagonist Triplion (S 18886; 10 nM). Acetylcholine and prostacyclin evoked biphasic responses during methoxamine constrictions; the constrictor part was blocked by Triplion. In ApoE-KO mouse kidneys, compared with C57BL6, a specific decrease in norepinephrine response and no modification in dilator responses were observed. In diabetic ApoE-KO mouse kidneys, constrictions to U 46619 and those to 8-iso-PGF2α were significantly and selectively augmented, without modification in the expression of the TP receptor, and again without any significant change in vasodilator activity. Thus TP receptors are functional, and their activation is not involved in norepinephrine, endothelin, and angiotensin II vasoconstrictions but is implicated in the unusual vasoconstrictions to acetylcholine and prostacyclin. Increased responsiveness of TP receptors occurs in diabetic ApoE-KO mouse kidneys. Thus early changes in TP receptor-mediated vasoconstrictor activity may participate in the development of kidney disease in atherosclerosis and diabetes.


2002 ◽  
Vol 11 (1) ◽  
pp. 21-30 ◽  
Author(s):  
Doris M. Tham ◽  
Baby Martin-McNulty ◽  
Yi-xin Wang ◽  
Dennis W. Wilson ◽  
Ronald Vergona ◽  
...  

Angiotensin II (ANG II) promotes vascular inflammation through nuclear factor-κB (NF-κB)-mediated induction of pro-inflammatory genes. The role of peroxisome proliferator-activated receptors (PPARs) in modulating vascular inflammation and atherosclerosis in vivo is unclear. The aim of the present study was to examine the effects of ANG II on PPARs and NF-κB-dependent pro-inflammatory genes in the vascular wall in an in vivo model of atherosclerosis and aneurysm formation. Six-month-old male apolipoprotein E-deficient (apoE-KO) mice were treated with ANG II (1.44 mg/kg per day for 30 days). ANG II enhanced vascular inflammation, accelerated atherosclerosis, and induced formation of abdominal aortic aneurysms. These effects of ANG II in the aorta were associated with downregulation of both PPAR-α and PPAR-γ mRNA and protein and an increase in transcription of monocyte chemotactic protein-1 (MCP-1), macrophage-colony stimulating factor (M-CSF), endothelial-selectin (E-selectin), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) throughout the entire aorta. ANG II also activated NF-κB with increases in both p52 and p65 NF-κB subunits. In summary, these in vivo results indicate that ANG II, through activation of NF-κB-mediated pro-inflammatory genes, promotes vascular inflammation, leading to acceleration of atherosclerosis and induction of aneurysm in apoE-KO mice. Downregulation of PPAR-α and -γ by ANG II may diminish the anti-inflammatory potential of PPARs, thus contributing to enhanced vascular inflammation.


Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Yoshinori Tsubakimoto ◽  
Hiroyuki Yamada ◽  
Hirokazu Yokoi ◽  
Hiroki Takata ◽  
Hiroyuki Kawahito ◽  
...  

[BACKGROUND] The angiotensin II (Ang II) type 1 (AT 1 ) receptor is crucially involved in atherogenesis, but bone marrow (BM) AT 1 -mediated proatherogenic action remains undefined- . [METHOD AND RESULT] BM-derived mononuclear cells (BM-MNCs) more abundantly express AT 1 than VSMCs (2.2 fold) with similar affinities to Ang II. BM cells in 8-week-old apoE-deficient −/− ) or wild-type (Agtr1 + / + ) cells. Four (apoE-KO) mice were replaced with AT 1 -deficient (Agtr1 weeks after the initiation of western diet and Ang II infusion (500ng/kg/min), atherosclerotic lesion area in aortic root was examined. ApoE-KO mice reconstituted with Agtr1 −/− marrow (apoE-KO/BM-Agtr1 −/− ) showed a significant reduction in atherosclerotic lesions compared with apoE-KO/BM-Agtr1 + / + mice (55%, P <0.05). The accumulation of macrophages was attenuated in apoE-KO/BM-Agtr1 −/− mice (55%, P <0.05), concomitant with a decrease in the number of circulating Ly-6C hi monocytes (76%, P <0.01). The numbers of circulating CCR2 + and CX3CR1 + monocytes were also reduced in apoE-KO/BM-Agtr1 −/− mice (87±16 vs 298±66; CCR2 + monocyte, 72±12 vs 550±119 cells/μl; CX3CR1 + monocyte, respectively, P <0.01). Furthermore, the number of macrophage progenitor cells defined by M-CSF stimulated macrophage colony-forming unit was markedly reduced by 82 % (p<0.01) in Agtr1 −/− compared with Agtr1 + / + mice. We next examined the effect of BM-AT 1 on the number of hematopoietic stem cells (HSCs), common myeloid progenitors (CMP), and granulocyte/macrophage progenitors (GMP) to determine at which point of the lineage pathway, BM-AT 1 is involved. The number of HSCs did not differ between the two groups (3.6±0.8 vs 2.9±0.6 × 10 3 cells/tibia, P =n.s.), whereas the numbers of CMP and GMP were much lower in apoE-KO/BM-Agtr1 −/− mice (4.7±0.7 vs 10.2±1.4 ×10 3 cells/tibia, 9.9±2.7 vs 20.2±2.8 × 10 3 cells/tibia, respectively, P <0.05). [CONCLUSION] BM-MNCs expressed the abundant densities of AT1, and AT1-mediated signals on BM-MNCs exaggerated atherosclerotic lesion development. BM-AT 1 is closely implicated in the differentiation of HSCs into macrophage progenitors and the behavior of monocytes/macrophages, indicating that BM-AT 1 could be a promising therapeutic target for the prevention of cardiovascular events.


2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
L Fang ◽  
K Ohashi ◽  
N Otaka ◽  
H Kawanishi ◽  
T Takikawa ◽  
...  

Abstract Background Abdominal aortic aneurysm (AAA) is an increasing and life-threatening disease. Obesity is associated with an increased risk of AAA. Omentin is a circulating adipokine, which is downregulated by obesity. Recently we have demonstrated that omentin is an anti-inflammatory adipokine that prevents the development of atherosclerosis in apolipoprotein-E knockout (apoE-KO) mice. Here we examined whether omentin could modulate angiotensin II-induced AAA formation in apoE-KO mice. Methods and results To overexpress human omentin in apoE-KO mice, apoE-KO mice were crossed with transgenic mice expressing the human omentin gene in fat tissue under the control of AP2 promoter (OMT-Tg mice). Circulating levels of human omentin in apoE-KO/OMT-Tg mice were approximately threefold higher than those in healthy human subjects, whereas human omentin was undetectable in apoE-KO mice. There were no differences in body weight, blood pressure and heart rate between apoE-KO/OMT-Tg and apoE-KO mice. We also subjected apoE-KO/OMT-Tg and apoE-KO mice at 24 weeks of age to continuous angiotensin II-infusion by using osmotic mini pumps for 4 weeks, which is a widely-accepted model of experimental AAA. ApoE-KO/OMT-Tg mice exhibited a lower incidence of AAA formation and a reduced maximal diameter of AAA determined by direct measurement and ultrasound imaging as compared with apo-E KO mice. In histological analyses with van Gieson staining, apoE-KO/OMT-Tg mice showed attenuated disruption of medial elastic fibers in response to angiotensin II compared with apo-E KO mice. ApoE-KO/OMT-Tg mice also displayed reduced mRNA levels of matrix metalloproteinase (MMP) 2 and MMP9 as well as pro-inflammation genes including interleukin (IL)-6 in aortic walls compared with apo-E KO mice. Treatment of human monocyte-derived macrophages with human omentin protein attenuated LPS-stimulated expression of MMP9, TNF-α and IL-6. Omentin treatment also reduced LPS-induced activation of MMP9 in cultured media of human macrophages as evaluated by gelatinolytic zymography. Omentin treatment increased phosphorylation levels of Akt in human macrophages. The suppressive effects of omentin on inflammatory response in macrophages were reversed by treatment with LY294002, which is an inhibitor of PI3 kinase/Akt signaling. Conclusion These data suggest that omentin acts as an adipokine that can attenuate angiotensin II-induced development of AAA through suppression of MMP activation and inflammatory response in the vascular wall.


Lipids ◽  
2015 ◽  
Vol 50 (9) ◽  
pp. 839-846 ◽  
Author(s):  
Futian Tang ◽  
Xiaoqiang Li ◽  
Yali Gui ◽  
Cuiling Qi ◽  
Meili Lu ◽  
...  
Keyword(s):  

2012 ◽  
Vol 109 (1) ◽  
pp. 17-24 ◽  
Author(s):  
Jeong Sook Noh ◽  
Yung Hyun Choi ◽  
Yeong Ok Song

The present study investigated the effects of 3′-(4′-hydroxyl-3′,5′-dimethoxyphenyl)propionic acid (HDMPPA), the active principle compound of kimchi, on vascular damage in the experimental atherosclerotic animal. HDMPPA was administrated by an intraperitoneal injection of 10 mg/kg per d for 8 weeks to apoE knockout (KO) mice with an atherogenic diet containing 1 % cholesterol, and its effects were compared with vehicle-treated control mice. HDMPPA increased NO content in the aorta, accompanied by a decrease in reactive oxygen species (ROS) concentration. Furthermore, in the HDMPPA-treated group, aortic endothelial NO synthase (eNOS) expression was up-regulated compared with the control group. These results suggested that HDMPPA could maintain NO bioavailability through an increasing eNOS expression and preventing NO degradation by ROS. Furthermore, HDMPPA treatment in apoE KO mice inhibited eNOS uncoupling through an increase in vascular tetrahydrobiopterin content and a decrease in serum asymmetric dimethylarginine levels. Moreover, HDMPPA ameliorates inflammatory-related protein expression in the aorta of apoE KO mice. Therefore, the present study suggests that HDMPPA, the active compound of kimchi, a Korean functional food, may exert its vascular protective effect through the preservation of NO bioavailability and suppression of the inflammatory response.


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