scholarly journals Altered Clock and Lipid Metabolism-Related Genes in Atherosclerotic Mice Kept with Abnormal Lighting Condition

2016 ◽  
Vol 2016 ◽  
pp. 1-14 ◽  
Author(s):  
Zhu Zhu ◽  
Bingxuan Hua ◽  
Zhanxian Shang ◽  
Gongsheng Yuan ◽  
Lirong Xu ◽  
...  

Background. The risk of atherosclerosis is elevated in abnormal lipid metabolism and circadian rhythm disorder. We investigated whether abnormal lighting condition would have influenced the circadian expression of clock genes and clock-controlled lipid metabolism-related genes in ApoE-KO mice.Methods. A mouse model of atherosclerosis with circadian clock genes expression disorder was established using ApoE-KO mice (ApoE-KO LD/DL mice) by altering exposure to light. C57 BL/6J mice (C57 mice) and ApoE-KO mice (ApoE-KO mice) exposed to normal day and night and normal diet served as control mice. According to zeitgeber time samples were acquired, to test atheromatous plaque formation, serum lipids levels and rhythmicity, clock genes, and lipid metabolism-related genes along with Sirtuin 1 (Sirt1) levels and rhythmicity.Results. Atherosclerosis plaques were formed in the aortic arch of ApoE-KO LD/DL mice. The serum lipids levels and oscillations in ApoE-KO LD/DL mice were altered, along with the levels and diurnal oscillations of circadian genes, lipid metabolism-associated genes, and Sirt1 compared with the control mice.Conclusions. Abnormal exposure to light aggravated plaque formation and exacerbated disorders of serum lipids and clock genes, lipid metabolism genes and Sirt1 levels, and circadian oscillation.

2021 ◽  
Vol 12 ◽  
Author(s):  
Gang Wang ◽  
Baihe Han ◽  
Ruoxi Zhang ◽  
Qi Liu ◽  
Xuedong Wang ◽  
...  

Hyperglycemia-induced endothelial cell senescence has been widely reported to be involved in the pathogenesis of type 2 diabetes mellitus‒accelerated atherosclerosis. Thus, understanding the underlying mechanisms and identifying potential therapeutic targets for endothelial cell senescence are valuable for attenuating atherosclerosis progression. C1q/tumor necrosis factor-related protein 9 (CTRP9), an emerging potential cardiokine, exerts a significant protective effect with respect to atherosclerosis, particularly in endothelial cells. However, the exact mechanism by which CTRP9 prevents endothelial cells from hyperglycemia-induced senescence remains unclear. This study aimed to investigate the effects of CTRP9 on hyperglycemia-induced endothelial cell senescence and atherosclerotic plaque formation in diabetic apolipoprotein E knockout (ApoE KO) mice. Human umbilical vein endothelial cells (HUVECs) were cultured in normal glucose (5.5 mM) and high glucose (40 mM) with or without recombinant human CTRP9 protein (3 μg/ml) for 48 h. Purified lentiviruses overexpressing CTRP9 (Lv-CTRP9) and control vectors containing green fluorescent protein (Lv-GFP) were injected via the tail vein into streptozotocin-induced diabetic ApoE KO mice. Results revealed that exposure of HUVECs to HG significantly increased the expression of Krüppel-like factor 4 (KLF4) and cyclin-dependent kinase inhibitor p21 (p21) and decreased that of telomerase reverse transcriptase (TERT). Treatment with recombinant human CTRP9 protein protected HUVECs from HG-induced premature senescence and dysfunction. CTRP9 promoted the phosphorylation of AMP-activated kinase (AMPK), attenuated the expression of KLF4 and p21 induced by HG, and increased the expression of TERT in HUVECs. Furthermore, in the background of AMPKα knockdown or KLF4 activation, the protective effects of CTRP9 were abolished. In-vivo experiments showed that the overexpression of CTRP9 inhibited vascular senescence and reduced atherosclerotic plaque formation in ApoE KO mice with diabetes. In conclusion, we demonstrate that KLF4 upregulation plays a crucial role in HG-induced endothelial senescence. This anti-atherosclerotic effect of CTRP9 may be partly attributed to the inhibition of HG-induced endothelial senescence through an AMPKα/KLF4-dependent mechanism, suggesting that CTRP9 could benefit further therapeutic approaches for type 2 diabetes mellitus‒accelerated atherosclerosis.


2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Courtney Whalen ◽  
Floyd Mattie ◽  
Alexandra Caamano ◽  
Elisabeth Bach ◽  
Neil Huang ◽  
...  

Abstract Objectives Hyperhomocysteinemia is an independent risk factor for atherosclerosis and cardiovascular disease through mechanisms still incompletely defined. We investigated the impact of mild diet-induced accumulation of homocysteine on atherosclerotic plaque formation in apoE knockout (KO) mice, a model for atherosclerosis in humans. We hypothesize that diet induced hyperhomocysteinemia will promote plaque development. Methods 7 wk-old male apoE-KO mice (n = 5) were fed a methyl-deficient diet for 16 wk. The diet consisted of a purified high (40%)-fat high-methionine diet with restricted levels of B vitamins and choline (HypoMet). A second group of animals (control, n = 5) was fed a normal-methyl matched diet. After 4 and 12 wk, plasma homocysteine was quantified by reverse phase HPLC with fluorometric detection, and a panel of inflammatory cytokines (MCP-1; TNF-; IL-17A/F; IL-2; IL-6, IL-10; KC/GRO; MIP-1; IFN-) were assayed (U-plex, Meso Scale Discovery). After 16 wk, mice were euthanized and perfusion-fixed aortas were stained for lipids (Oil Red-O) and subjected to 2-D-quantification of stained plaque (Image J software), and to 3-D analysis by magnetic resonance imaging (MRI, Agilent 14-tesla microimaging system). Standard 3-D gradient echo imaging yielded a resolution of 20 microns isotropic. Data were reconstructed using Matlab and segmented to obtain plaque volumes using Avizo 9.0. Results HypoMet-mice had significantly higher plasma homocysteine (µM), when compared to controls, at 4 wk (10.6 ± 4.5 vs 2.3 ± 0.8, P < 0.05) and 12 wk (7.6 ± 1.5 vs 2.5 ± 1.1, P < 0.05). No significant differences were observed in inflammatory cytokines. Surprisingly, Oil Red-O staining revealed that HypoMet-mice did not display more plaque coverage (37 ± 6.9%) than controls (54.4 ± 10.4%). 14-T MRI results (Fig.1) confirmed that HypoMet-mice did not present higher plaque volumes than controls (0.61 ± 0.18 mm3 vs 1.2 ± 0.35 mm3, for HypoMet mice vs controls). Conclusions A mild accumulation of homocysteine, induced by a methyl-deficient diet, did not favor atherosclerosis formation in the aortas of apoE-KO mice. Future analysis of intracellular hypomethylation may explain the observed effects of mild hyperhomocysteinemia on plaque formation. Funding Sources Graduate Program and University Funding. Supporting Tables, Images and/or Graphs


2017 ◽  
Vol 114 (4) ◽  
pp. E550-E559 ◽  
Author(s):  
Rayomand S. Khambata ◽  
Suborno M. Ghosh ◽  
Krishnaraj S. Rathod ◽  
Tharssana Thevathasan ◽  
Federica Filomena ◽  
...  

Reduced bioavailable nitric oxide (NO) plays a key role in the enhanced leukocyte recruitment reflective of systemic inflammation thought to precede and underlie atherosclerotic plaque formation and instability. Recent evidence demonstrates that inorganic nitrate (NO3−) through sequential chemical reduction in vivo provides a source of NO that exerts beneficial effects upon the cardiovascular system, including reductions in inflammatory responses. We tested whether the antiinflammatory effects of inorganic nitrate might prove useful in ameliorating atherosclerotic disease in Apolipoprotein (Apo)E knockout (KO) mice. We show that dietary nitrate treatment, although having no effect upon total plaque area, caused a reduction in macrophage accumulation and an elevation in smooth muscle accumulation within atherosclerotic plaques of ApoE KO mice, suggesting plaque stabilization. We also show that in nitrate-fed mice there is reduced systemic leukocyte rolling and adherence, circulating neutrophil numbers, neutrophil CD11b expression, and myeloperoxidase activity compared with wild-type littermates. Moreover, we show in both the ApoE KO mice and using an acute model of inflammation that this effect upon neutrophils results in consequent reductions in inflammatory monocyte expression that is associated with elevations of the antiinflammatory cytokine interleukin (IL)-10. In summary, we demonstrate that inorganic nitrate suppresses acute and chronic inflammation by targeting neutrophil recruitment and that this effect, at least in part, results in consequent reductions in the inflammatory status of atheromatous plaque, and suggest that this effect may have clinical utility in the prophylaxis of inflammatory atherosclerotic disease.


Author(s):  
Sidney D. Kobernick ◽  
Edna A. Elfont ◽  
Neddra L. Brooks

This cytochemical study was designed to investigate early metabolic changes in the aortic wall that might lead to or accompany development of atherosclerotic plaques in rabbits. The hypothesis that the primary cellular alteration leading to plaque formation might be due to changes in either carbohydrate or lipid metabolism led to histochemical studies that showed elevation of G-6-Pase in atherosclerotic plaques of rabbit aorta. This observation initiated the present investigation to determine how early in plaque formation and in which cells this change could be observed.Male New Zealand white rabbits of approximately 2000 kg consumed normal diets or diets containing 0.25 or 1.0 gm of cholesterol per day for 10, 50 and 90 days. Aortas were injected jin situ with glutaraldehyde fixative and dissected out. The plaques were identified, isolated, minced and fixed for not more than 10 minutes. Incubation and postfixation proceeded as described by Leskes and co-workers.


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


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.


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.


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