NUMERICAL MODELING OF ATHEROSCLEROSIS LESION EVOLUTION IN TIME I. INITIAL STAGE OF THE DISEASE

2016 ◽  
Vol 16 (05) ◽  
pp. 1650068
Author(s):  
SAFOORA KARIMI ◽  
MITRA DADVAR ◽  
BAHRAM DABIR

Atherosclerosis is one of the main causes of death in the developed world. The disease, which is an inflammatory disease, has been the focus of many studies. A few studies attempted to model atherosclerosis lesion development mathematically while no attention has been paid to the multistage nature of the disease. The present study provides a mathematical model for atherosclerosis evolution by focusing on the inflammatory responses of the initial stage of the disease. In the model, the inflammatory response in type I lesion, which includes endothelium dysfunction, LDL oxidation, monocytes entry, foam cell formation and intima property changes, are coupled with the transport equations of blood and LDL in lumen and arterial wall. The innovation of the model is determination of the duration of the initial stage of lesion propagation for a specific patient while the presence of leaky junction in endothelial layer and LDL oxidation in the intima layer are considered. The greatest advantage of the study in comparison with previous studies is to provide a model for the initiating stage of the atherosclerosis development so that a more precise result of the disease evolution is obtained.

Author(s):  
Dun Niu ◽  
Lanfang Li ◽  
Zhizhong Xie

Chloride channel 3 (ClC-3), a Cl−/H+ antiporter, has been well established as a member of volume-regulated chloride channels (VRCCs). ClC-3 may be a crucial mediator for activating inflammation-associated signaling pathways by regulating protein phosphorylation. A growing number of studies have indicated that ClC-3 overexpression plays a crucial role in mediating increased plasma low-density lipoprotein levels, vascular endothelium dysfunction, pro-inflammatory activation of macrophages, hyper-proliferation and hyper-migration of vascular smooth muscle cells (VSMCs), as well as oxidative stress and foam cell formation, which are the main factors responsible for atherosclerotic plaque formation in the arterial wall. In the present review, we summarize the molecular structures and classical functions of ClC-3. We further discuss its emerging role in the atherosclerotic process. In conclusion, we explore the potential role of ClC-3 as a therapeutic target for atherosclerosis.


2018 ◽  
Vol 132 (23) ◽  
pp. 2493-2507 ◽  
Author(s):  
Yuki Sato ◽  
Rena Watanabe ◽  
Nozomi Uchiyama ◽  
Nana Ozawa ◽  
Yui Takahashi ◽  
...  

Vasostatin-1, a chromogranin A (CgA)-derived peptide (76 amino acids), is known to suppress vasoconstriction and angiogenesis. A recent study has shown that vasostatin-1 suppresses the adhesion of human U937 monocytes to human endothelial cells (HECs) via adhesion molecule down-regulation. The present study evaluated the expression of vasostatin-1 in human atherosclerotic lesions and its effects on inflammatory responses in HECs and human THP-1 monocyte-derived macrophages, macrophage foam cell formation, migration and proliferation of human aortic smooth muscle cells (HASMCs) and extracellular matrix (ECM) production by HASMCs, and atherogenesis in apolipoprotein E-deficient (ApoE−/−) mice. Vasostatin-1 was expressed around Monckeberg’s medial calcific sclerosis in human radial arteries. Vasostatin-1 suppressed lipopolysaccharide (LPS)-induced up-regulation of monocyte chemotactic protein-1 (MCP-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin in HECs. Vasostatin-1 suppressed inflammatory M1 phenotype and LPS-induced interleukin-6 (IL-6) secretion via nuclear factor-κB (NF-κB) down-regulation in macrophages. Vasostatin-1 suppressed oxidized low-density lipoprotein (oxLDL)-induced foam cell formation associated with acyl-CoA:cholesterol acyltransferase-1 (ACAT-1) and CD36 down-regulation and ATP-binding cassette transporter A1 (ABCA1) up-regulation in macrophages. In HASMCs, vasostatin-1 suppressed angiotensin II (AngII)-induced migration and collagen-3 and fibronectin expression via decreasing ERK1/2 and p38 phosphorylation, but increased elastin expression and matrix metalloproteinase (MMP)-2 and MMP-9 activities via increasing Akt and JNK phosphorylation. Vasostatin-1 did not affect the proliferation and apoptosis in HASMCs. Four-week infusion of vasostatin-1 suppressed the development of aortic atherosclerotic lesions with reductions in intra-plaque inflammation, macrophage infiltration, and SMC content, and plasma glucose level in ApoE−/− mice. These results indicate the inhibitory effects of vasostatin-1 against atherogenesis. The present study provided the first evidence that vasostatin-1 may serve as a novel therapeutic target for atherosclerosis.


Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Takuya Watanabe ◽  
Yoshitaka Iso ◽  
Shinji Koba ◽  
Tetsuo Sakai ◽  
Gang Xu ◽  
...  

Human heregulins, neuregulin-1 type I polypeptides known to activate proliferation, differentiation, and survival of glial cells, neurons, and myocytes, were recently found to be expressed in macrophage foam cells within human coronary atherosclerotic lesions. Macrophage foam cell formation, characterized by cholesterol ester (CE) accumulation, is modulated by scavenger receptor class A (SR-A), acyl-CoA:cholesterol acyltransferase-1 (ACAT1), and ATP-binding cassette transporter A1 (ABCA1). The present study clarified the functional roles of heregulins in macrophage foam cell formation and atherosclerosis. Plasma heregulin-beta1 levels were significantly decreased in 31 patients with acute coronary syndrome (ACS) and 33 patients with stable angina pectoris as compared with 34 mild hypertensive patients and 40 healthy volunteers (1.3+/−0.3, 2.0+/−0.4 versus 7.6+/−1.4, 8.2+/−1.2 ng/mL; at least P < 0.01). Immunoreactive heregulins and these receptor c-erbB3 were detectable within human coronary atherothrombosis obtained from ACS patients. In primary cultured human monocyte-macrophages, the expression of endogenous heregulins, heregulin-beta1, and c-erbB3 increased during monocytic differentiation into macrophages. In human macrophages differentiated by 7-day culture, exogenous heregulin-beta1, but not heregulin-alpha, significantly reduced acetylated low-density lipoprotein (acLDL)-induced CE accumulation by reducing SR-A and ACAT1 expression and by increasing ABCA1 expression at both mRNA and protein levels. Heregulin-beta1 significantly decreased endocytic uptake of [ 125 I]acLDL and increased cholesterol efflux by apolipoprotein A1 from human macrophages. Chronic infusion of heregulin-beta1 by osmotic mini-pumps into apolipoprotein E-deficient mice significantly suppressed the progression of macrophage-driven atherosclerotic lesions by 64%. Our study provides the first evidence that heregulin-beta1 may participate in anti-atherogenesis by suppressing macrophage foam cell formation via SR-A and ACAT1 down-regulation and ABCA1 up-regulation.


2016 ◽  
Vol 36 (suppl_1) ◽  
Author(s):  
Shuhong Hu ◽  
Li Zhu

Atherosclerosis is a chronic inflammatory disease of the arterial wall elicited by accumulation of LDL and leucocytes in the subendothelium at predilection sites with disturbed laminar flow. Chemokines and their receptors appear to act as critical players in atherosclerosis as they not only direct atherogenic recruitment of leucocytes but also exert cell hemostatic functions by chemokine ligand-receptor axes and their specific or combined contributions. Atypical chemokine (C-C motif) receptor-like 2 (CCRL2) cooperates with its ligand chemerin and leukocyte-expressed chemerin receptor chemokine-like receptor 1 (CMKLR1) to regulate cell trafficking and inflammatory responses,but its role in atherosclerosis is not clear. To investigate whether CCRL2 contributes to the pathomechanism of atherogenesis, we generated CCRL2 -/- mice in hyperlipidemic atherosclerosis-prone ApoE -/- background and found that the atherosclerotic plaque area of the total aorta was significantly reduced compared with CCRL2 +/+ ApoE -/- mice on a high fat diet. The protective effect of CCRL2 deficiency was anatomically isolated primarily to the site of disturbed blood flow (D-flow) in the aortic arch but not in the descending aorta. Endothelial CCRL2 was upregulated in response to D-flow and either CCRL2 or CMKLR1 deletion reduced plaque formation. Further studies showed that CCRL2 co-localized with CMKLR1 and chemerin within the atherosclerotic aorta root. CCRL2 deficiency led to significantly less lipid deposition in aortic root, reduced CMKLR1 + leukocyte rolling on lesional vascular endothelium, diminished macrophage accumulation and foam cell formation, and polarized macrophage to an M2-like phenotype. These results demonstrate that D-flow induction of vascular CCRL2 is required for optimal formation of atherosclerotic plaques via coordinating the accumulation of CMKLR1 + monocytes/macrophages within the vascular wall, and thus identifies CCRL2 as a novel drug target to prevent or treat atherosclerosis. This work was supported by Natural Science Foundation of China (grant 81370373 to L.Z. and 31300781 to C.T.) Key Words: atherosclerosis, CCRL2, chemerin, macrophage


Biomolecules ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 715
Author(s):  
Jae-Yong Kim ◽  
Soonok Kim ◽  
Sang Hee Shim

An endophytic fungus, Neofusicoccum parvum JS-0968, was isolated from a plant, Vitex rotundifolia. The chemical investigation of its cultures led to the isolation of a secondary metabolite, (3R)-5-hydroxymellein. It has been reported to have antifungal, antibacterial, and antioxidant activity, but there have been no previous reports on the effects of (3R)-5-hydroxymellein on atherosclerosis. The oxidation of lipoproteins and foam cell formation have been known to be significant in the development of atherosclerosis. Therefore, we investigated the inhibitory effects of (3R)-5-hydroxymellein on atherosclerosis through low-density lipoprotein (LDL) and high-density lipoprotein (HDL) oxidation and macrophage foam cell formation. LDL and HDL oxidation were determined by measuring the production of conjugated dienes and malondialdehyde, the amount of hyperchromicity and carbonyl content, conformational changes, and anti-LDL oxidation. In addition, the inhibition of foam cell formation was measured by Oil red O staining. As a result, (3R)-5-hydroxymellein suppressed the oxidation of LDL and HDL through the inhibition of lipid peroxidation, the decrease of negative charges, the reduction of hyperchromicity and carbonyl contents, and the prevention of apolipoprotein A-I (ApoA-I) aggregation and apoB-100 fragmentation. Furthermore, (3R)-5-hydroxymellein significantly reduced foam cell formation induced by oxidized LDL (oxLDL). Taken together, our data show that (3R)-5-hydroxymellein could be a potential preventive agent for atherosclerosis via obvious anti-LDL and HDL oxidation and the inhibition of foam cell formation.


2020 ◽  
Vol 21 (21) ◽  
pp. 8312
Author(s):  
Takashi Obama ◽  
Hiroyuki Itabe

Neutrophil extracellular traps (NETs) significantly contribute to various pathophysiological conditions, including cardiovascular diseases. NET formation in the vasculature exhibits inflammatory and thrombogenic activities on the endothelium. NETs are induced by various stimulants such as exogenous damage-associated molecular patterns (DAMPs). Oxidatively modified low-density lipoprotein (oxLDL) has been physiologically defined as a subpopulation of LDL that comprises various oxidative modifications in the protein components and oxidized lipids, which could act as DAMPs. oxLDL has been recognized as a crucial initiator and accelerator of atherosclerosis through foam cell formation by macrophages; however, recent studies have demonstrated that oxLDL stimulates neutrophils to induce NET formation and enhance NET-mediated inflammatory responses in vascular endothelial cells, thereby suggesting that oxLDL may be involved in cardiovascular diseases through neutrophil activation. As NETs comprise myeloperoxidase and proteases, they have the potential to mediate oxidative modification of LDL. This review summarizes recent updates on the analysis of NETs, their implications for cardiovascular diseases, and prospects for a possible link between NET formation and oxidative modification of lipoproteins.


2016 ◽  
Vol 36 (suppl_1) ◽  
Author(s):  
Huan Tao ◽  
Patricia G Yancey ◽  
John L Blakemore ◽  
Youmin Zhang ◽  
Lei Ding ◽  
...  

Background: Autophagy modulates vascular cell lipid metabolism, lipid droplet turnover, foam cell formation, cell survival and death, and inflammation. Scavenger receptor class B type I (SR-BI) deficiency causes impaired lysosome function in macrophages and erythrocytes. Methods and Results: Bone marrow transplantation studies were performed in ApoE and LDLR deficient mice to examine the effects of hematopoietic SR-BI deletion on atherosclerotic lesion autophagy. In addition, in vitro studies compared WT versus SR-BI -/- macrophages. Under conditions of cholesterol induced stress, the mRNA and protein levels of critical autophagy players including ATG5, ATG6/Belcin-1, ATG7 and LC3II were decreased by 37.8% to 84.6% (P<0.05 to 0.01) in SR-B1 -/- macrophages and atherosclerotic aortic tissue compared to controls. Electron microscopic analysis showed that SR-BI -/- versus WT macrophages had 80% fewer (P<0.05) autophagsomes in response to cholesterol enrichment. Macrophage SR-BI deficiency led to 1.8-fold (P<0.05) more lipid deposition and 2.5-fold more (P<0.01) apoptosis in response to oxidized LDL. Furthermore, hematopoietic SR-BI deletion caused 2.3 fold (P<0.05) more cell death in aortic atherosclerotic lesions compared to the WT control. Pharmacologic activation of autophagy did not reduce the levels of lipid droplets or cell apoptosis in SR-BI null macrophages vs WT control. WT peritoneal macrophages were used to examine SR-BI subcellular distribution and its interaction with VPS34/Beclin-1. In response to induction of autophagy, macrophage SR-BI was expressed in lysosomes and co-localized with LC3-II. Furthermore, we found that SR-BI directly interacted with the VPS34/Beclin-1 complex. Conclusions: SR-BI deficiency leads to defective autophagy and accelerates macrophage foam cell formation and apoptosis in experimental mouse atherosclerotic lesions. Macrophage SR-BI regulates expression of critical autophagy players and directly modulates autophagy via the VPS34/Beclin-1 pathway, identifying novel targets for the treatment of atherosclerosis.


2009 ◽  
Vol 10 (2) ◽  
pp. e903
Author(s):  
M Iizuka ◽  
Y Kishimoto ◽  
E Saita ◽  
K Suzuki ◽  
M Toyozaki ◽  
...  

2006 ◽  
Vol 13 (2-4) ◽  
pp. 203-208 ◽  
Author(s):  
Eduardo F. Borba ◽  
Jozelio F. Carvalho ◽  
Eloísa Bonfá

Autoimmunity and inflammation are associated with marked changes in lipid and lipoprotein metabolism in SLE. Autoantibodies and cytokines are able to modulate lipoprotein lipase (LPL) activity, a key enzyme in lipid metabolism, with a consequent “lupus pattern” of dyslipoproteinemia characterized by elevated levels of very low-density lipoprotein cholesterol (VLDL) and triglycerides (TG) and lower high-density lipoprotein cholesterol (HDL) levels. This pattern favors an enhanced LDL oxidation with a subsequent deleterious foam cell formation. Autoantibodies and immunocomplexes may aggravate this oxidative injury by inducing accumulation and deposition of oxLDL in endothelial cells. Drugs and associated diseases usually magnify the close interaction of these factors and further promote the proatherogenic environment of this disease.


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