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Sample records for apolipoprotein-e deficient mice

  1. Motor and cognitive deficits in apolipoprotein E-deficient mice after closed head injury.

    PubMed

    Chen, Y; Lomnitski, L; Michaelson, D M; Shohami, E

    1997-10-01

    Previous studies suggest that traumatic brain injury is associated with increased risk factor for developing Alzheimer's disease. Furthermore, the extent of the risk seems to be most pronounced in Alzheimer's disease patients who carry the epsilon4 allele of apolipoprotein E, suggesting a connection between susceptibility to head trauma and the apolipoprotein E genotype. Apolipoprotein E-deficient mice provide a useful model for investigating the role of this lipoprotein in neuronal maintenance and repair. In the present study apolipoprotein E-deficient mice and a closed head injury experimental paradigm were used to examine the role of apolipoprotein E in brain susceptibility to head trauma and in neuronal repair. Apolipoprotein E-deficient mice were assessed up to 40 days after closed head injury for neurological and cognitive functions, as well as for histopathological changes in the hippocampus. A neurological severity score used for clinical assessment revealed more severe motor and behavioural deficits in the apolipoprotein E-deficient mice than in the controls, the impairment persisting for at least 40 days after injury. Performance in the Morris water maze, which tests spatial memory, showed a marked learning deficit of the apolipoprotein E-deficient mice when compared with injured controls, which was apparent for at least 40 days. At this time, histopathological examination revealed overt neuronal cell death bilaterally in the hippocampus of the injured apolipoprotein E-deficient mice. The finding that apolipoprotein E-deficient mice exhibit an impaired ability to recover from closed head injury suggests that apolipoprotein E plays an important role in neuronal repair following injury and highlights the applicability of this mouse model to the study of the cellular and molecular mechanisms involved.

  2. Digoxin reduces atherosclerosis in apolipoprotein E-deficient mice.

    PubMed

    Shi, Huairui; Mao, Xiaobo; Zhong, Yucheng; Liu, Yuzhou; Zhao, Xiaoqi; Yu, Kunwu; Zhu, Ruirui; Wei, Yuzhen; Zhu, Jianghao; Sun, Haitao; Mao, Yi; Zeng, Qiutang

    2016-05-01

    Numerous in vitro studies have suggested that digoxin suppresses inflammation and alters lipid metabolism. However, the effect of dioxin on atherosclerosis is poorly understood. The present study was conducted to determine whether digoxin affects the development of atherosclerosis in a murine model of atherosclerotic disease. Apolipoprotein E-deficient mice maintained on a Western-type diet were administered PBS (control), low-dose digoxin (1 mg · kg(-1) · day(-1)) or high-dose digoxin (2 mg · kg(-1) · day(-1)) via i.p. injection for 12 weeks. Digoxin dose-dependently reduced atherosclerotic lesion formation and plasma lipid levels (reductions of 41% in total cholesterol, 54% in triglycerides and 20% in low-density lipoprotein cholesterol in the high-dose digoxin-treated group). Moreover, treatment with digoxin markedly attenuated IL-17A expression and IL-17A-related inflammatory responses and increased the abundance of regulatory T cells (Tregs). Our data demonstrate that digoxin acts as a specific antagonist of retinoid-related orphan receptor-γ to decrease atherosclerosis by suppressing lipid levels and IL-17A-related inflammatory responses. © 2016 The British Pharmacological Society.

  3. Isoliquiritigenin Attenuates Atherogenesis in Apolipoprotein E-Deficient Mice

    PubMed Central

    Du, Fen; Gesang, Quzhen; Cao, Jia; Qian, Mei; Ma, Li; Wu, Dongfang; Yu, Hong

    2016-01-01

    Isoliquiritigenin (ISL) exhibits antioxidation and anti-inflammation activity. We sought to investigate the effects and mechanism of ISL on the development of atherosclerotic lesions in apolipoprotein E-deficient (apoE−/−) mice. Firstly, we determined that ISL reduced the mRNA levels of inflammatory factors interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), and monocyte chemotactic protein-1 (MCP-1), while it increased the expression of several lipoprotein-related genes in peritoneal macrophages treated with lipopolysaccharide (LPS). ISL also enhanced peroxisome proliferator-activated receptor gamma (PPARγ) protein levels and reversed the changes of ATP-binding cassette transporter A (ABCA1) and cluster of differentiation 36 (CD36) in macrophages treated with oxidative low-density lipoprotein (ox-LDL). Then, in an in vivo study, female apoE−/− mice were fed a Western diet with ISL (0, 20, 100 mg/kg/day) added for 12 weeks. We found that ISL decreased the plasma cholesterol levels of very low-density lipoprotein (VLDL)/LDL, promoted plasma superoxide dismutase (SOD) and paraoxonase-1 (PON1) activities, and decreased plasma IL-6, TNF-α, and MCP-1 levels. Moreover, ISL significantly reduced the atherosclerotic lesions and hepatic steatosis in apoE−/− mice. In the liver, ISL altered the expression of several key genes (such as SRBI, ABCA1, ABCG8, PPARγ, and FASN) involving cholesterol-selective uptake and excretion into bile, triglyceride (TG) biosynthesis, and inflammation. These results suggest that the atheroprotective effects of ISL are due to the improvement of lipid metabolism, antioxidation, and anti-inflammation, which involve PPARγ-dependent signaling. PMID:27869741

  4. Cardiovascular effects of uremia in apolipoprotein E-deficient mice.

    PubMed

    Bro, Susanne

    2009-11-01

    The purpose of this thesis work was to establish an experimental mouse model for studying the pathogenesis and therapy of accelerated atherosclerosis in uremia. Uremia was induced by surgical 5/6 nephrectomy in apolipoprotein E-deficient (apoE-/-) mice and led to development of severe aortic atherosclerosis independently of BP and plasma homocysteine levels. Also, the accelerated atherosclerosis could not be fully explained by changes in total plasma cholesterol. Morphologic and biochemical analyses of aortas suggested that accelerated initiation and expansion rather than a specific uremic lesion composition characterize atherosclerosis in the uremic mice. Increased expression of inflammatory genes in aortas of uremic mice suggests that an augmented inflammatory response in the arterial wall might be an important impetus for accelerated atherosclerosis in uremia. A marked downregulation of expression of smooth muscle cell assigned genes indicates that besides intimal atherosclerosis, uremic vasculopathy in apoE-/- mice is characterized by a uremia-specific medial smooth muscle cell degeneration. Oxidative stress could also be important for the development of atherosclerotic lesions in uremia. In the mouse model, uremia led to a marked increase of titers of antibodies against oxidized LDL (OxLDL), and increased circulating levels of the oxidized phospholipid epitope EO6. Treatment with enalapril (an ACE inhibitor) almost completely prevented the development of accelerated aortic atherosclerosis in uremic mice. This effect was parallelled by reductions of aortic expression of the proinflammatory adhesion molecule VCAM-1, and plasma titers of IgM antibodies against OxLDL, and was at least partly independent of BP-lowering. To test the involvement of the receptor for advanced glycation end products (RAGE) in development of uremic atherosclerosis, uremic mice were treated with a neutralizing RAGE-antibody. This treatment reduced the aortic plaque area fraction by 59% in

  5. Cerebral lipid deposition in aged apolipoprotein-E-deficient mice.

    PubMed

    Walker, L C; Parker, C A; Lipinski, W J; Callahan, M J; Carroll, R T; Gandy, S E; Smith, J D; Jucker, M; Bisgaier, C L

    1997-11-01

    To assess the influence of age and diet on cerebral pathology in mice lacking apolipoprotein E (apoE), four male apoE knockout mice (epsilon -/-), and five male wild-type (epsilon +/+) littermate controls were placed on a high-fat/high-cholesterol diet for 7 weeks beginning at 17 months of age. All four aged knockout mice developed xanthomatous lesions in the brain consisting mostly of crystalline cholesterol clefts, lipid globules, and foam cells. Smaller xanthomas were confined mainly to the choroid plexus and ventral fornix in the roof of the third ventricle, occasionally extending subpially along the choroidal fissure and into the adjacent parenchyma. More advanced xanthomas disrupted adjoining neural tissue in the fornix, hippocampus, and dorsal diencephalon; in one case, over 60% of one telencephalic hemisphere, including nearly the entire neocortex, was obliterated by the lesion. No xanthomas were observed in aged wild-type controls fed the high-fat/high-cholesterol diet. Brains from 42 additional animals, fed only conventional chow, were examined; 3 of 15 aged (15- to 23-month-old) apoE knockout mice developed small choroidal xanthomas. In contrast, no lesions were observed in five young (2- to 4-month-old) apoE knockout mice or in any wild-type controls between the ages of 2 and 23 months. Our findings indicate that disorders of lipid metabolism can induce significant pathological changes in the central nervous system of aged apoE knockout mice, particularly those on a high-fat/high-cholesterol diet. It may be fruitful to seek potential interactions between genetic factors and diet in modulating the risk of Alzheimer's disease and other neurodegenerative disorders in aged humans.

  6. Cerebral lipid deposition in aged apolipoprotein-E-deficient mice.

    PubMed Central

    Walker, L. C.; Parker, C. A.; Lipinski, W. J.; Callahan, M. J.; Carroll, R. T.; Gandy, S. E.; Smith, J. D.; Jucker, M.; Bisgaier, C. L.

    1997-01-01

    To assess the influence of age and diet on cerebral pathology in mice lacking apolipoprotein E (apoE), four male apoE knockout mice (epsilon -/-), and five male wild-type (epsilon +/+) littermate controls were placed on a high-fat/high-cholesterol diet for 7 weeks beginning at 17 months of age. All four aged knockout mice developed xanthomatous lesions in the brain consisting mostly of crystalline cholesterol clefts, lipid globules, and foam cells. Smaller xanthomas were confined mainly to the choroid plexus and ventral fornix in the roof of the third ventricle, occasionally extending subpially along the choroidal fissure and into the adjacent parenchyma. More advanced xanthomas disrupted adjoining neural tissue in the fornix, hippocampus, and dorsal diencephalon; in one case, over 60% of one telencephalic hemisphere, including nearly the entire neocortex, was obliterated by the lesion. No xanthomas were observed in aged wild-type controls fed the high-fat/high-cholesterol diet. Brains from 42 additional animals, fed only conventional chow, were examined; 3 of 15 aged (15- to 23-month-old) apoE knockout mice developed small choroidal xanthomas. In contrast, no lesions were observed in five young (2- to 4-month-old) apoE knockout mice or in any wild-type controls between the ages of 2 and 23 months. Our findings indicate that disorders of lipid metabolism can induce significant pathological changes in the central nervous system of aged apoE knockout mice, particularly those on a high-fat/high-cholesterol diet. It may be fruitful to seek potential interactions between genetic factors and diet in modulating the risk of Alzheimer's disease and other neurodegenerative disorders in aged humans. Images Figure 1 Figure 2 PMID:9358763

  7. Factor XI Deficiency Protects Against Atherogenesis in Apolipoprotein E/Factor XI Double Knockout Mice.

    PubMed

    Shnerb Ganor, Reut; Harats, Dror; Schiby, Ginette; Gailani, David; Levkovitz, Hanna; Avivi, Camila; Tamarin, Ilia; Shaish, Aviv; Salomon, Ophira

    2016-03-01

    Atherosclerosis and atherothrombosis are still major causes of mortality in the Western world, even after the widespread use of cholesterol-lowering medications. Recently, an association between local thrombin generation and atherosclerotic burden has been reported. Here, we studied the role of factor XI (FXI) deficiency in the process of atherosclerosis in mice. Apolipoprotein E/FXI double knockout mice, created for the first time in our laboratory. There was no difference in cholesterol levels or lipoprotein profiles between apolipoprotein E knockout and double knockout mice. Nevertheless, in 24-week-old double knockout mice, the atherosclerotic lesion area in the aortic sinus was reduced by 32% (P=0.004) in comparison with apolipoprotein E knockout mice. In 42-week-old double knockout mice, FXI deficiency inhibited atherosclerosis progression significantly in the aortic sinus (25% reduction, P=0.024) and in the aortic arch (49% reduction, P=0.028), with a prominent reduction of macrophage infiltration in the atherosclerotic lesions. FXI deprivation was shown to slow down atherogenesis in mice. The results suggest that the development of atherosclerosis can be prevented by targeting FXI. © 2016 American Heart Association, Inc.

  8. FAD286, an aldosterone synthase inhibitor, reduced atherosclerosis and inflammation in apolipoprotein E-deficient mice.

    PubMed

    Gamliel-Lazarovich, Aviva; Gantman, Anna; Coleman, Raymond; Jeng, Arco Y; Kaplan, Marielle; Keidar, Shlomo

    2010-09-01

    Aldosterone is known to be involved in atherosclerosis and cardiovascular disease and blockade of its receptor was shown to improve cardiovascular function. It was, therefore, hypothesized that inhibition of aldosterone synthesis would also reduce atherosclerosis development. To test this hypothesis, we examined the effect of FAD286 (FAD), an aldosterone synthase inhibitor, on the development of atherosclerosis in spontaneous atherosclerotic apolipoprotein E-deficient mice. Mice were divided into three treatment groups: normal diet, low-salt diet (LSD) and LSD treated with FAD at 30 mg/kg per day (LSD + FAD) for 10 weeks. Histomorphometry of the aortas obtained from these mice showed that atherosclerotic lesion area increased by three-fold under LSD compared with normal diet and FAD significantly reduced lesion area to values similar to normal diet. Changes in atherosclerosis were paralleled by changes in the expression of the inflammation markers (C-reactive protein, monocyte chemotactic protein-1, interleukin-6, nuclear factor kappa B and intercellular adhesion molecule-1) in peritoneal macrophages obtained from these mice. Surprisingly, whereas LSD increased serum or urine aldosterone levels, FAD did not alter these levels when evaluated at the end of the study. In J774A.1 macrophage-like cell line stimulated with lipopolysaccharide, FAD was shown to have a direct dose-dependent anti-inflammatory effect. In apolipoprotein E-deficient mice, FAD reduces atherosclerosis and inflammation. However, these actions appeared to be dissociated from its effect on inhibition of aldosterone synthesis.

  9. Suppressive effects of cacao polyphenols on the development of atherosclerosis in apolipoprotein E-deficient mice.

    PubMed

    Natsume, Midori; Baba, Seigo

    2014-01-01

    Previous studies in humans have shown that the cacao polyphenols, (-)-epicatechin and its oligomers, prevent in vitro and ex vivo low-density lipoprotein oxidation mediated by free radical generators and metal ions and also reduce plasma LDL-cholesterol levels. The aim of this study was to examine the effects of cacao polyphenols on the development of atherosclerosis in apolipoprotein E-deficient (-/-) mice. Mice aged 8 weeks (n = 90) were randomized into three groups, and fed either normal mouse chow (controls) or chow supplemented with 0.25 or 0.40 % cacao polyphenols for 16 weeks. The mean plaque area in cross-sections of the brachiocephalic trunk was measured and found to be lower in the 0.25 % cacao polyphenol group than in the control group (p < 0.05). Pathological observations showed that accumulation of cholesterol crystals in the plaque area was greater in the control group compared with the 0.40 % cacao polyphenol group (p < 0.05). Immunochemical staining in the 0.25 and 0.40 % groups showed that expression of the cell adhesion molecules (VCAM-1 and ICAM-1) and production of oxidative stress markers (4-hydroxynonenal, hexanoyl-lysine, and dityrosine) were reduced in cross-sections of the brachiocephalic trunk. These results suggest that cacao polyphenols inhibit the development of atherosclerosis in apolipoprotein E-deficient (-/-) mice by reducing oxidative stress and inflammatory responses.

  10. Tau hyperphosphorylation in apolipoprotein E-deficient and control mice after closed head injury.

    PubMed

    Genis, L; Chen, Y; Shohami, E; Michaelson, D M

    2000-05-15

    Apolipoprotein E (apoE)-deficient mice have learning and memory impairments that are associated with specific neurochemical changes and hyperphosphorylation of distinct epitopes of the cytoskeletal protein tau. Furthermore, such mice are highly susceptible to the sequelae of brain trauma and their ability to recover from head injury is impaired. In the present study we investigated the extent that the neuronal maintenance and repair impairments of apoE-deficient mice are related to aberrations at the tau phosphorylation level. This was pursued by subjecting control and apoE-deficient mice to closed head injury (CHI) and examination, utilizing immunoblot assays, of the resulting effects on tau phosphorylation. The results thus obtained revealed that tau of apoE-deficient mice is hyperphosphorylated before CHI and that this insult results in transient tau hyperphosphorylation, whose extent and time course in the two mouse groups varied markedly. Tau hyperphosphorylation in the injured controls was maximal by about 4 hr after injury and reverted to basal levels by 24 hr. In contrast, almost no head injury-induced tau hyperphosphorylation was observed in the apoE-deficient mice at 4 hr after injury. Some tau hyper-phosphorylation was detected in the head-injured apoE-deficient mice after longer time intervals, but its extent was markedly lower than the maximal values obtained in the head injured controls. These findings show that the chronic neuronal impairments brought about by apoE deficiency and the acute response to head injury are both associated with hyperphosphorylation of the same tau domain and that the ability of apoE-deficient mice to mount the acute tau hyperphosphorylation response to head injury is impaired.

  11. Inhibition of platelet aggregation ex vivo is repressed in apolipoprotein E deficient mice.

    PubMed

    Carrier, É; Houde, M; Grandbois, M; Bkaily, G; Warner, T D; D'Orléans-Juste, P

    2017-08-01

    In the present study, we assessed whether the endogenous platelet inhibitory mechanisms are altered in the early to moderate stages of the atherosclerotic process. Apolipoprotein E deficient mice (ApoE-/-), a mouse model of atherosclerosis, and their wild-type (WT) counterparts were used to assess agonist-stimulated synthesis of prostacyclin (PGI2), inhibition of platelet aggregation ex vivo, and intra-platelet cAMP levels. Basal U46619 and ADP -induced platelet aggregation in vitro were increased in ApoE-/- mice at 18-20 weeks in comparison with 8-10 weeks of age. Systemically administered endothelin-1 (ET-1) or bradykinin (BK) inhibited platelet aggregation in a similar fashion in 8- to 10-week-old ApoE-/- and WT mice, but not in the ApoE-/- mice at 18-20 weeks of age, although both peptides maintained their capacity to increase plasma levels of the PGI2. Intravenous infusion of PGI2 also failed to inhibit platelet aggregation ex vivo in 18- to 20-week-old ApoE-/- mice. Interestingly, both BK and PGI2 retained their ability to increase intraplatelet cAMP in WT and ApoE-/- mice. Our results suggest that a loss of activity of endogenous inhibitorymechanisms could contribute to the increased platelet reactivity in ApoE-/- mice, and that this phenomenon occurs early in the intermediate stage of the atherosclerotic process.

  12. Disruption of p21-activated kinase 1 gene diminishes atherosclerosis in apolipoprotein E-deficient mice

    PubMed Central

    Singh, Nikhlesh K.; Kotla, Sivareddy; Dyukova, Elena; Traylor Jr., James G.; Orr, A. Wayne; Chernoff, Jonathan; Marion, Tony N.; Rao, Gadiparthi N.

    2015-01-01

    Pak1 plays an important role in various cellular processes, including cell motility, polarity, survival and proliferation. To date, its role in atherogenesis has not been explored. Here we report the effect of Pak1 on atherogenesis using atherosclerosis-prone apolipoprotein E-deficient (ApoE−/−) mice as a model. Disruption of Pak1 in ApoE−/− mice results in reduced plaque burden, significantly attenuates circulating IL-6 and MCP-1 levels, limits the expression of adhesion molecules and diminishes the macrophage content in the aortic root of ApoE−/− mice. We also observed reduced oxidized LDL uptake and increased cholesterol efflux by macrophages and smooth muscle cells of ApoE−/−:Pak1−/− mice as compared with ApoE−/− mice. In addition, we detect increased Pak1 phosphorylation in human atherosclerotic arteries, suggesting its role in human atherogenesis. Altogether, these results identify Pak1 as an important factor in the initiation and progression of atherogenesis. PMID:26104863

  13. Inhibition of Interleukin-10 Signaling Induces Microbiota-Dependent Chronic Colitis in Apolipoprotein E Deficient Mice

    PubMed Central

    Singh, Vishal; Kumar, Manish; Yeoh, Beng San; Xiao, Xia; Saha, Piu; Kennett, Mary J.; Vijay-Kumar, Matam

    2015-01-01

    Background Apolipoprotein E (ApoE) mediates potent anti-inflammatory and immunomodulatory properties in addition to its roles in regulating cholesterol transport and metabolism. However, its role in the intestine, specifically during inflammation is largely unknown. Methods Mice [C57BL/6 or ApoE deficient (ApoE-KO) mice] were administered either single or four injections (weekly) of anti-interleukin (IL)-10 receptor monoclonal antibody (1.0 mg/mouse; intraperitoneally) and euthanized one week after the last injection. 16S rRNA sequencing was performed in fecal samples to analyze the gut bacterial load and its composition. Microbiota was ablated by administration of broad-spectrum antibiotics in drinking water. IL-10KO mice were cohoused with ApoE-KO mice or their WT littermates to monitor the colitogenic potential of gut microbiota harbored in ApoE-KO mice. Results ApoE-KO mice developed severe colitis upon neutralization of IL-10 signaling as assessed by every parameter analyzed. 16S rRNA sequencing revealed that the ApoE-KO mice display elevated and altered gut microbiota that were accompanied with impaired production of intestinal antimicrobial peptides. Interestingly, microbiota ablation ameliorates the colitis development in ApoE-KO mice. Exacerbated and accelerated colitis was observed in IL-10KO mice when cohoused with ApoE-KO mice. Conclusions Our study highlights a novel interplay between ApoE and IL-10 in maintaining gut homeostasis and that such cross-talk may play a critical role in inflammatory bowel disease (IBD) pathogenesis. Gut sterilization and cohousing experiment suggests that microbiota play pivotal role in the development of IBD in mice lacking ApoE. PMID:26891260

  14. Allergic lung inflammation promotes atherosclerosis in apolipoprotein E-deficient mice.

    PubMed

    Liu, Cong-Lin; Wang, Yi; Liao, Mengyang; Santos, Marcela M; Fernandes, Cleverson; Sukhova, Galina K; Zhang, Jin-Ying; Cheng, Xiang; Yang, Chongzhe; Huang, Xiaozhu; Levy, Bruce; Libby, Peter; Wu, Gongxiong; Shi, Guo-Ping

    2016-05-01

    Inflammation drives asthma and atherosclerosis. Clinical studies suggest that asthmatic patients have a high risk of atherosclerosis. Yet this hypothesis remains uncertain, given that Th2 imbalance causes asthma whereas Th1 immunity promotes atherosclerosis. In this study, chronic allergic lung inflammation (ALI) was induced in mice by ovalbumin sensitization and challenge. Acute ALI was induced in mice by ovalbumin and aluminum sensitization and ovalbumin challenge. Atherosclerosis was produced in apolipoprotein E-deficient (Apoe(-/-)) mice with a Western diet. When chronic ALI and atherosclerosis were produced simultaneously, ALI increased atherosclerotic lesion size, lesion inflammatory cell content, elastin fragmentation, smooth muscle cell (SMC) loss, lesion cell proliferation, and apoptosis. Production of acute ALI before atherogenesis did not affect lesion size, but increased atherosclerotic lesion CD4(+) T cells, lesion SMC loss, angiogenesis, and apoptosis. Production of acute ALI after atherogenesis also did not change atherosclerotic lesion area, but increased lesion elastin fragmentation, cell proliferation, and apoptosis. In mice with chronic ALI and diet-induced atherosclerosis, daily inhalation of a mast cell inhibitor or corticosteroid significantly reduced atherosclerotic lesion T-cell and mast cell contents, SMC loss, angiogenesis, and cell proliferation and apoptosis, although these drugs did not affect lesion area, compared with those that received vehicle treatment. In conclusion, both chronic and acute ALI promote atherogenesis or aortic lesion pathology, regardless whether ALI occurred before, after, or at the same time as atherogenesis. Antiasthmatic medication can efficiently mitigate atherosclerotic lesion pathology.

  15. Osteopontin deficiency reduces kidney damage from hypercholesterolemia in Apolipoprotein E-deficient mice

    PubMed Central

    Pei, Zouwei; Okura, Takafumi; Nagao, Tomoaki; Enomoto, Daijiro; Kukida, Masayoshi; Tanino, Akiko; Miyoshi, Ken-ichi; Kurata, Mie; Higaki, Jitsuo

    2016-01-01

    Hypercholesterolemia is a well-established risk factor for kidney injury, which can lead to chronic kidney disease (CKD). Osteopontin (OPN) has been implicated in the pathology of several renal conditions. This study was to evaluate the effects of OPN on hypercholesterolemia induced renal dysfunction. Eight-week-old male mice were divided into 4 groups: apolipoprotein E knockout (ApoE−/−) and ApoE/OPN knockout (ApoE−/−/OPN−/−) mice fed a normal diet (ND) or high cholesterol diet (HD). After 4 weeks, Periodic acid-Schiff (PAS) and oil red O staining revealed excessive lipid deposition in the glomeruli of ApoE−/−HD mice, however, significantly suppressed in ApoE−/−/OPN−/−HD mice. Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) expression was lower in the glomeruli of ApoE−/−/OPN−/−HD mice than ApoE−/−HD mice. In vitro study, primary mesangial cells were incubated with recombinant mouse OPN (rmOPN). RmOPN induced LOX-1 mRNA and protein expression in primary mesangial cells. Pre-treatment with an ERK inhibitor suppressed the LOX-1 gene expression induced by rmOPN. These results indicate that OPN contributes to kidney damage in hypercholesterolemia and suggest that inhibition of OPN may provide a potential therapeutic target for the prevention of hypercholesterolemia. PMID:27353458

  16. Familial apolipoprotein E deficiency.

    PubMed Central

    Schaefer, E J; Gregg, R E; Ghiselli, G; Forte, T M; Ordovas, J M; Zech, L A; Brewer, H B

    1986-01-01

    A unique kindred with premature cardiovascular disease, tubo-eruptive xanthomas, and type III hyperlipoproteinemia (HLP) associated with familial apolipoprotein (apo) E deficiency was examined. Homozygotes (n = 4) had marked increases in cholesterol-rich very low density lipoproteins (VLDL) and intermediate density lipoproteins (IDL), which could be effectively lowered with diet and medication (niacin, clofibrate). Homozygotes had only trace amounts of plasma apoE, and accumulations of apoB-48 and apoA-IV in VLDL, IDL, and low density lipoproteins. Radioiodinated VLDL apoB and apoE kinetic studies revealed that the homozygous proband had markedly retarded fractional catabolism of VLDL apoB-100, apoB-48 and plasma apoE, as well as an extremely low apoE synthesis rate as compared to normals. Obligate heterozygotes (n = 10) generally had normal plasma lipids and mean plasma apoE concentrations that were 42% of normal. The data indicate that homozygous familial apoE deficiency is a cause of type III HLP, is associated with markedly decreased apoE production, and that apoE is essential for the normal catabolism of triglyceride-rich lipoprotein constituents. Images PMID:3771793

  17. Kaempferol regulates OPN-CD44 pathway to inhibit the atherogenesis of apolipoprotein E deficient mice

    SciTech Connect

    Xiao, Hong-Bo; Lu, Xiang-Yang; Sun, Zhi-Liang; Zhang, Heng-Bo

    2011-12-15

    Recent studies show that osteopontin (OPN) and its receptor cluster of differentiation 44 (CD44) are two pro-inflammatory cytokines contributing to the development of atherosclerosis. The objective of this study was to explore the inhibitory effect of kaempferol, a naturally occurring flavonoid compound, on atherogenesis and the mechanisms involved. The experiments were performed in aorta and plasma from C57BL/6J control and apolipoprotein E-deficient (ApoE{sup -/-}) mice treated or not with kaempferol (50 or 100 mg/kg, intragastrically) for 4 weeks. Kaempferol treatment decreased atherosclerotic lesion area, improved endothelium-dependent vasorelaxation, and increased the maximal relaxation value concomitantly with decrease in the half-maximum effective concentration, plasma OPN level, aortic OPN expression, and aortic CD44 expression in ApoE{sup -/-} mice. In addition, treatment with kaempferol also significantly decreased reactive oxygen species production in mice aorta. The present results suggest that kaempferol regulates OPN-CD44 pathway to inhibit the atherogenesis of ApoE{sup -/-} mice. -- Graphical abstract: Kaempferol regulates OPN-CD44 pathway to inhibit the atherogenesis of ApoE{sup -/-} mice. Highlights: Black-Right-Pointing-Pointer OPN-CD44 pathway plays a critical role in the development of atherosclerosis. Black-Right-Pointing-Pointer We examine lesion area, OPN and CD44 changes after kaempferol treatment. Black-Right-Pointing-Pointer Kaempferol treatment decreased atherosclerotic lesion area in ApoE{sup -/-} mice. Black-Right-Pointing-Pointer Kaempferol treatment decreased aortic OPN and CD44 expressions in ApoE{sup -/-} mice. Black-Right-Pointing-Pointer Kaempferol regulates OPN-CD44 pathway to inhibit the atherogenesis.

  18. Iron-ion radiation accelerates atherosclerosis in apolipoprotein E-deficient mice.

    PubMed

    Yu, Tao; Parks, Brian W; Yu, Shaohua; Srivastava, Roshni; Gupta, Kiran; Wu, Xing; Khaled, Saman; Chang, Polly Y; Kabarowski, Janusz H; Kucik, Dennis F

    2011-06-01

    Radiation exposure from a number of terrestrial sources is associated with an increased risk for atherosclerosis. Recently, concern over whether exposure to cosmic radiation might pose a similar risk for astronauts has increased. To address this question, we examined the effect of 2 to 5 Gy iron ions ((56)Fe), a particularly damaging component of cosmic radiation, targeted to specific arterial sites in male apolipoprotein E-deficient (apoE(-/-)) mice. Radiation accelerated the development of atherosclerosis in irradiated portions of the aorta independent of any systemic effects on plasma lipid profiles or circulating leukocytes. Further, radiation exposure resulted in a more rapid progression of advanced aortic root lesions, characterized by larger necrotic cores associated with greater numbers of apoptotic macrophages and reduced lesional collagen compared to sham-treated mice. Intima media thickening of the carotid arteries was also exacerbated. Exposure to (56)Fe ions can therefore accelerate the development of atherosclerotic lesions and promote their progression to an advanced stage characterized by compositional changes indicative of increased thrombogenicity and instability. We conclude that the potential consequences of radiation exposure for astronauts on prolonged deep-space missions are a major concern. Knowledge gained from further studies with animal models should lead to a better understanding of the pathophysiological effects of accelerated ion radiation to better estimate atherogenic risk and develop appropriate countermeasures to mitigate its damaging effects.

  19. IL-20 is expressed in atherosclerosis plaques and promotes atherosclerosis in apolipoprotein E-deficient mice.

    PubMed

    Chen, Wei-Yu; Cheng, Bor-Chih; Jiang, Meei-Jyh; Hsieh, Mei-Yi; Chang, Ming-Shi

    2006-09-01

    Atherosclerosis is a chronic inflammatory disease with immune cell infiltration. Various cytokines and chemokines have been characterized as pro- or antiatherogenic factors. Interleukin-20 (IL-20) belongs to the IL-10 family and is a proinflammatory cytokine involved in the pathogenesis of psoriasis. However, the association between IL-20 and atherosclerosis is undetermined. Therefore, we sought to investigate whether IL-20 is associated with atherosclerosis. We examined the expression of IL-20 and its receptor complex IL-20R1/IL-20R2 in atherosclerotic lesions of humans and mice using immunohistochemical staining. IL-20 was expressed in macrophage-rich areas. Both IL-20 and IL-20R1/IL-20R2 were expressed by endothelial cells lining the intimal microvessels, vasa vasorum, but rarely in nonatherosclerotic arteries. We used reverse-transcription polymerase chain reaction to analyze gene expression. IL-20 transcripts increased in hypoxic monocytes and monocytes treated with oxidized low-density lipoprotein. The expression of IL-20R1 and IL-20R2 was also upregulated by human umbilical vein endothelial cells in response to hypoxic treatment. Incubating IL-20 with human umbilical vein endothelial cells upregulated CXCL9 and CXCL11 transcripts. Furthermore, in vivo administration of IL-20 expression vector using intramuscular electroporation promoted atherosclerosis in apolipoprotein E-deficient mice. Our data suggest that IL-20 is a proatherogenic cytokine that contributes to the progression of atherosclerosis.

  20. Hypoxanthine induces cholesterol accumulation and incites atherosclerosis in apolipoprotein E-deficient mice and cells.

    PubMed

    Ryu, Hye-Myung; Kim, You-Jin; Oh, Eun-Joo; Oh, Se-Hyun; Choi, Ji-Young; Cho, Jang-Hee; Kim, Chan-Duck; Park, Sun-Hee; Kim, Yong-Lim

    2016-11-01

    Reactive oxygen species (ROS) generation during purine metabolism is associated with xanthine oxidase and uric acid. However, the direct effect of hypoxanthine on ROS generation and atherosclerosis has not been evaluated. Smoking and heavy drinking are associated with elevated levels of hypoxanthine. In this study, we investigated the role of hypoxanthine on cholesterol synthesis and atherosclerosis development, particularly in apolipoprotein E (APOE)-deficient mice. The effect of hypoxanthine on the regulation of cholesterol synthesis and atherosclerosis were evaluated in Apoe knockout (KO) mice and cultured HepG2 cells. Hypoxanthine markedly increased serum cholesterol levels and the atherosclerotic plaque area in Apoe KO mice. In HepG2 cells, hypoxanthine increased intracellular ROS production. Hypoxanthine increased cholesterol accumulation and decreased APOE and ATP-binding cassette transporter A1 (ABCA1) mRNA and protein expression in HepG2 cells. Furthermore, H2 O2 also increased cholesterol accumulation and decreased APOE and ABCA1 expression. This effect was partially reversible by treatment with the antioxidant N-acetyl cysteine and allopurinol. Hypoxanthine and APOE knockdown using APOE-siRNA synergistically induced cholesterol accumulation and reduced APOE and ABCA1 expression. Hypoxanthine induces cholesterol accumulation in hepatic cells through alterations in enzymes that control lipid transport and induces atherosclerosis in APOE-deficient cells and mice. These effects are partially mediated through ROS produced in response to hypoxanthine. © 2016 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  1. Endothelial Surface Layer Degradation by Chronic Hyaluronidase Infusion Induces Proteinuria in Apolipoprotein E-Deficient Mice

    PubMed Central

    Kuikhoven, Mayella; Heeneman, Sylvia; Lutgens, Esther; Gijbels, Marion J. J.; Nieuwdorp, Max; Peutz, Carine J.; Stroes, Erik S. G.; Vink, Hans; van den Berg, Bernard M.

    2010-01-01

    Objective Functional studies show that disruption of endothelial surface layer (ESL) is accompanied by enhanced sensitivity of the vasculature towards atherogenic stimuli. However, relevance of ESL disruption as causal mechanism for vascular dysfunction remains to be demonstrated. We examined if loss of ESL through enzymatic degradation would affect vascular barrier properties in an atherogenic model. Methods Eight week old male apolipoprotein E deficient mice on Western-type diet for 10 weeks received continuous active or heat-inactivated hyaluronidase (10 U/hr, i.v.) through an osmotic minipump during 4 weeks. Blood chemistry and anatomic changes in both macrovasculature and kidneys were examined. Results Infusion with active hyaluronidase resulted in decreased ESL (0.32±0.22 mL) and plasma volume (1.03±0.18 mL) compared to inactivated hyaluronidase (0.52±0.29 mL and 1.28±0.08 mL, p<0.05 respectively).Active hyaluronidase increased proteinuria compared to inactive hyaluronidase (0.27±0.02 vs. 0.15±0.01 µg/µg protein/creatinin, p<0.05) without changes in glomerular morphology or development of tubulo-interstitial inflammation. Atherosclerotic lesions in the aortic branches showed increased matrix production (collagen, 32±5 vs. 18±3%; glycosaminoglycans, 11±5 vs. 0.1±0.01%, active vs. inactive hyaluronidase, p<0.05). Conclusion ESL degradation in apoE deficient mice contributes to reduced increased urinary protein excretion without significant changes in renal morphology. Second, the induction of compositional changes in atherogenic plaques by hyaluronidase point towards increased plaque vulnerability. These findings support further efforts to evaluate whether ESL restoration is a valuable target to prevent (micro) vascular disease progression. PMID:21170388

  2. Influence of depleted uranium on hepatic cholesterol metabolism in apolipoprotein E-deficient mice.

    PubMed

    Souidi, M; Racine, R; Grandcolas, L; Grison, S; Stefani, J; Gourmelon, P; Lestaevel, P

    2012-04-01

    Depleted uranium (DU) is uranium with a lower content of the fissile isotope U-235 than natural uranium. It is a radioelement and a waste product from the enrichment process of natural uranium. Because of its very high density, it is used in the civil industry and for military purposes. DU exposure can affect many vital systems in the human body, because in addition to being weakly radioactive, uranium is a toxic metal. It should be emphasized that, to be exposed to radiation from DU, you have to eat, drink, or breathe it, or get it on your skin. This particular study is focusing on the health effects of DU for the cholesterol metabolism. Previous studies on the same issue have shown that the cholesterol metabolism was modulated at molecular level in the liver of laboratory rodents contaminated for nine months with DU. However, this modulation was not correlated with some effects at organs or body levels. It was therefore decided to use a "pathological model" such as hypercholesterolemic apolipoprotein E-deficient laboratory mice in order to try to clarify the situation. The purpose of the present study is to assess the effects of a chronic ingestion (during 3 months) of a low level DU-supplemented water (20 mg L(-1)) on the above mentioned mice in order to determine a possible contamination effect. Afterwards the cholesterol metabolism was studied in the liver especially focused on the gene expressions of cholesterol-catabolising enzymes (CYP7A1, CYP27A1 and CYP7B1), as well as those of associated nuclear receptors (LXRα, FXR, PPARα, and SREBP 2). In addition, mRNA levels of other enzymes of interest were measured (ACAT 2, as well as HMGCoA Reductase and HMGCoA Synthase). The gene expression study was completed with SRB1 and LDLr, apolipoproteins A1 and B and membrane transporters ABC A1, ABC G5. The major effect induced by a low level of DU contamination in apo-E deficient mice was a decrease in hepatic gene expression of the enzyme CYP7B1 (-23%) and nuclear

  3. Xyloketal B Attenuates Atherosclerotic Plaque Formation and Endothelial Dysfunction in Apolipoprotein E Deficient Mice

    PubMed Central

    Zhao, Li-Yan; Li, Jie; Yuan, Feng; Li, Mei; Zhang, Quan; Huang, Yun-Ying; Pang, Ji-Yan; Zhang, Bin; Sun, Fang-Yun; Sun, Hong-Shuo; Li, Qian; Cao, Lu; Xie, Yu; Lin, Yong-Cheng; Liu, Jie; Tan, Hong-Mei; Wang, Guan-Lei

    2015-01-01

    Our previous studies demonstrated that xyloketal B, a novel marine compound with a unique chemical structure, has strong antioxidant actions and can protect against endothelial injury in different cell types cultured in vitro and model organisms in vivo. The oxidative endothelial dysfunction and decrease in nitric oxide (NO) bioavailability are critical for the development of atherosclerotic lesion. We thus examined whether xyloketal B had an influence on the atherosclerotic plaque area in apolipoprotein E-deficient (apoE−/−) mice fed a high-fat diet and investigated the underlying mechanisms. We found in our present study that the administration of xyloketal B dose-dependently decreased the atherosclerotic plaque area both in the aortic sinus and throughout the aorta in apoE−/− mice fed a high-fat diet. In addition, xyloketal B markedly reduced the levels of vascular oxidative stress, as well as improving the impaired endothelium integrity and NO-dependent aortic vasorelaxation in atherosclerotic mice. Moreover, xyloketal B significantly changed the phosphorylation levels of endothelial nitric oxide synthase (eNOS) and Akt without altering the expression of total eNOS and Akt in cultured human umbilical vein endothelial cells (HUVECs). Here, it increased eNOS phosphorylation at the positive regulatory site of Ser-1177, while inhibiting phosphorylation at the negative regulatory site of Thr-495. Taken together, these findings indicate that xyloketal B has dramatic anti-atherosclerotic effects in vivo, which is partly due to its antioxidant features and/or improvement of endothelial function. PMID:25874925

  4. Beta-amyloid protein-containing inclusions in skeletal muscle of apolipoprotein-E-deficient mice.

    PubMed Central

    Robertson, T. A.; Dutton, N. S.; Martins, R. N.; Roses, A. D.; Kakulas, B. A.; Papadimitriou, J. M.

    1997-01-01

    The tibialis anterior muscle and soleus muscle of apolipoprotein-E-deficient mice were examined by light and electron microscopy. By light microscopy, sarcoplasmic inclusions were seen in tibialis anterior muscle and 40% of type 2 myofibers were affected in all animals over 8 months of age. These inclusions reacted for nonspecific esterase, cytochrome oxidase, and myoadenylate deaminase and were also periodic acid Schiff positive and stained basophilic with hematoxylin. Moreover, they reacted immunocytochemically with an antibody specific to fragment 17 to 24 of the published sequence of Alzheimer's cerebrovascular amyloid peptide. Immunoreactivity was lost when the antibody was adsorbed with the appropriate synthetic peptide. Ultrastructurally, the inclusions consisted of tubular arrays and were similar to those observed in human muscle in several pathological conditions. In type 1 myofibers of both tibialis anterior and soleus muscle, however, mitochondrial abnormalities including an increase in their number and size were detected, but tubular aggregates were not seen. These large mitochondria possessed an electron-dense inner chamber with an increased number of tightly packed cristae. The results obtained suggest that in these mice there is a disturbed lipid metabolism in skeletal muscle fibers that manifests itself with an accumulation of phospholipid in the form of sarcoplasmic reticulum tubules in the type 2 fibers and enlarged mitochondria with tightly packed cristae in the type 1 fibers. In addition, beta-amyloid protein was closely associated with the accumulated tubules and vesicles of sarcoplasmic reticulum and may represent dysregulation of amyloid precursor protein metabolism. Images Figure 1 Figure 2 Figure 3 PMID:9033257

  5. Nitric oxide-releasing agent, LA419, reduces atherogenesis in apolipoprotein E-deficient mice.

    PubMed

    Carnicer, Ricardo; Guillén, Natalia; Arbonés-Mainar, José M; Navarro, María A; Guzmán, Mario A; Barranquero, Cristina; Arnal, Carmen; Gascón, Sonia; Acín, Sergio; Mourelle, Marisabel; Osada, Jesús

    2009-05-01

    LA419 is a novel nitric oxide-donor with antioxidant properties. The effect of this compound on the development of atherosclerosis was investigated in apolipoprotein E-deficient mice. Male mice were randomized to receive vehicle or 5 mg/kg/day LA419 for 12 weeks. At the end of this period, plasma lipid and lipoprotein parameters, oxidative stress markers and hepatic fat, and mRNA levels were measured as well as en face and cross-sectional lesion areas of the aorta. Data showed that LA419 administration reduced atherosclerotic foci and cross-sectional lesion areas by decreasing the intimae presence of macrophage-derived foam cells despite an increase in plasma cholesterol. This agent induced a significant reduction in body weight gain and mass of adipose tissue. Furthermore, compared with placebo, LA419 administration significantly reduced plasma triglycerides and apolipoprotein C-III levels as well as systemic oxidative stress, estimated by plasma 8-isoprostane. Conversely, nonesterified fatty acid and HDL cholesterol levels remained unchanged, as well as apolipoproteins A-I, A-IV, and B and paraoxonase activity. Plasma triglycerides were significantly associated with plasma levels of apolipoprotein C-III and hepatic Fsp27 mRNA expression. These results indicate that administration of LA419 modulates lesion development. These actions are partly independent of total cholesterol as well as HDL particles and related to triglyceridemia and oxidative stress. Hypotriglyceridemia is associated with an equal number of apoB-containing particles. Hence, LA419 administration could be used as a safe alternative to control the metabolic syndrome and atherosclerosis.

  6. Alanyl-glutamine attenuates 5-fluorouracil-induced intestinal mucositis in apolipoprotein E-deficient mice

    PubMed Central

    Araújo, C.V.; Lazzarotto, C.R.; Aquino, C.C.; Figueiredo, I.L.; Costa, T.B.; de Oliveira Alves, L.A.; Ribeiro, R.A.; Bertolini, L.R.; Lima, A.A.M.; Brito, G.A.C.; Oriá, R.B.

    2015-01-01

    Apolipoprotein E (APOE=gene, apoE=protein) is a known factor regulating the inflammatory response that may have regenerative effects during tissue recovery from injury. We investigated whether apoE deficiency reduces the healing effect of alanyl-glutamine (Ala-Gln) treatment, a recognized gut-trophic nutrient, during tissue recovery after 5-FU-induced intestinal mucositis. APOE-knockout (APOE-/-) and wild-type (APOE+/+) C57BL6J male and female mice (N=86) were given either Ala-Gln (100 mM) or phosphate buffered saline (PBS) by gavage 3 days before and 5 days after a 5-fluorouracil (5-FU) challenge (450 mg/kg, via intraperitoneal injection). Mouse body weight was monitored daily. The 5-FU cytotoxic effect was evaluated by leukometry. Intestinal villus height, villus/crypt ratio, and villin expression were monitored to assess recovery of the intestinal absorptive surface area. Crypt length, mitotic, apoptotic, and necrotic crypt indexes, and quantitative real-time PCR for insulin-like growth factor-1 (IGF-1) and B-cell lymphoma 2 (Bcl-2) intestinal mRNA transcripts were used to evaluate intestinal epithelial cell turnover. 5-FU challenge caused significant weight loss and leukopenia (P<0.001) in both mouse strains, which was not improved by Ala-Gln. Villus blunting, crypt hyperplasia, and reduced villus/crypt ratio (P<0.05) were found in all 5-FU-challenged mice but not in PBS controls. Ala-Gln improved villus/crypt ratio, crypt length and mitotic index in all challenged mice, compared with PBS controls. Ala-Gln improved villus height only in APOE-/- mice. Crypt cell apoptosis and necrotic scores were increased in all mice challenged by 5-FU, compared with untreated controls. Those scores were significantly lower in Ala-Gln-treated APOE+/+ mice than in controls. Bcl-2 and IGF-1 mRNA transcripts were reduced only in the APOE-/--challenged mice. Altogether our findings suggest APOE-independent Ala-Gln regenerative effects after 5-FU challenge. PMID:25945744

  7. P-selectin glycoprotein ligand-1 deficiency leads to cytokine resistance and protection against atherosclerosis in apolipoprotein E deficient mice.

    PubMed

    Luo, Wei; Wang, Hui; Ohman, Miina K; Guo, Chiao; Shi, Kate; Wang, Julia; Eitzman, Daniel T

    2012-01-01

    Adhesive interactions between endothelial cells and leukocytes contribute to atherosclerotic plaque growth. However, mechanism(s) responsible for endothelial priming and deactivation in inflammatory diseases such as atherosclerosis are not clear. Apolipoprotein E deficient mice were generated with deficiency of P-selectin glycoprotein ligand-1 (Psgl-1(-/-), ApoE(-/-)). On both standard chow and Western diet, Psgl-1(-/-), ApoE(-/-) mice were protected against atherosclerosis compared to Psgl-1(+/+), ApoE(-/-) controls. Psgl-1(-/-), ApoE(-/-) mice also showed reduced leukocyte rolling and firm attachment on endothelial cells, however, adoptively transferred Psgl-1(+/+), ApoE(-/-) leukocytes into Psgl-1(-/-), ApoE(-/-) hosts displayed similar reduced rolling as Psgl-1(-/-), ApoE(-/-) leukocytes. Hematopoietic deficiency of Psgl-1 conferred resistance to the effects of interleukin-1β (IL-1β) on leukocyte rolling along with reduced circulating levels of sP-sel and sE-sel. Antibody blockade of Psgl-1 also reduced endothelial activation in response to IL-1β, eliminated leukocyte rolling, and was protective against atherosclerosis in ApoE(-/-) mice. Monocyte depletion with clodronate restored the endothelial response to IL-1β in Psgl-1(-/-) mice. This study suggests that Psgl-1 deficiency leads to reduced atherosclerosis and adhesive interactions between endothelial cells and leukocytes by indirectly regulating endothelial responses to cytokine stimulation. Published by Elsevier Ireland Ltd.

  8. P2Y receptors and atherosclerosis in apolipoprotein E-deficient mice

    PubMed Central

    Guns, Pieter-Jan DF; Hendrickx, Jan; Van Assche, Tim; Fransen, Paul; Bult, Hidde

    2010-01-01

    Background and purpose: P2Y nucleotide receptors are involved in the regulation of vascular tone, smooth muscle cell (SMC) proliferation and inflammatory responses. The present study investigated whether they are involved in atherosclerosis. Experimental approach: mRNA of P2Y receptors was quantified (RT-PCR) in atherosclerotic and plaque-free aorta segments of apolipoprotein E-deficient (apoE–/–) mice. Macrophage activation was assessed in J774 macrophages, and effects of non-selective purinoceptor antagonists on atherosclerosis were evaluated in cholesterol-fed apoE–/– mice. Key results: P2Y6 receptor mRNA was consistently elevated in segments with atherosclerosis, whereas P2Y2 receptor expression remained unchanged. Expression of P2Y1 or P2Y4 receptor mRNA was low or undetectable, and not influenced by atherosclerosis. P2Y6 mRNA expression was higher in cultured J774 macrophages than in cultured aortic SMCs. Furthermore, immunohistochemical staining of plaques demonstrated P2Y6-positive macrophages, but few SMCs, suggesting that macrophage recruitment accounted for the increase in P2Y6 receptor mRNA during atherosclerosis. In contrast to ATP, the P2Y6-selective agonist UDP increased mRNA expression and activity of inducible nitric oxide synthase and interleukin-6 in J774 macrophages; this effect was blocked by suramin (100–300 µM) or pyridoxal-phosphate-6-azophenyl-2′-4′-disulphonic acid (PPADS, 10–30 µM). Finally, 4-week treatment of cholesterol-fed apoE–/– mice with suramin or PPADS (50 and 25 mg·kg−1·day−1 respectively) reduced plaque size, without changing plaque composition (relative SMC and macrophage content) or cell replication. Conclusions and implications: These results suggest involvement of nucleotide receptors, particularly P2Y6 receptors, during atherosclerosis, and warrant further research with selective purinoceptor antagonists or P2Y6 receptor-deficient mice. PMID:20050854

  9. Protease-Activated Receptor-2 Deficiency Attenuates Atherosclerotic Lesion Progression and Instability in Apolipoprotein E-Deficient Mice.

    PubMed

    Zuo, Pengfei; Zuo, Zhi; Zheng, Yueyue; Wang, Xin; Zhou, Qianxing; Chen, Long; Ma, Genshan

    2017-01-01

    Inflammatory mechanisms are involved in the process of atherosclerotic plaque formation and rupture. Accumulating evidence suggests that protease-activated receptor (PAR)-2 contributes to the pathophysiology of chronic inflammation on the vasculature. To directly examine the role of PAR-2 in atherosclerosis, we generated apolipoprotein E/PAR-2 double-deficient mice. Mice were fed with high-fat diet for 12 weeks starting at ages of 6 weeks. PAR-2 deficiency attenuated atherosclerotic lesion progression with reduced total lesion area, reduced percentage of stenosis and reduced total necrotic core area. PAR-2 deficiency increased fibrous cap thickness and collagen content of plaque. Moreover, PAR-2 deficiency decreased smooth muscle cell content, macrophage accumulation, matrix metallopeptidase-9 expression and neovascularization in plaque. Relative quantitative PCR assay using thoracic aorta revealed that PAR-2 deficiency reduced mRNA expression of inflammatory molecules, such as vascular cell adhesion molecule-1, intercellular adhesion molecule-1, tumor necrosis factor (TNF)-α and monocyte chemoattractant protein (MCP)-1. In vitro experiment, we found that PAR-2 deficiency reduced mRNA expression of interferon-γ, interleukin-6, TNF-α and MCP-1 in macrophage under unstimulated and lipopolysaccharide-stimulated conditions. These results suggest that PAR-2 deficiency attenuates the progression and instability of atherosclerotic plaque.

  10. Site-specific dephosphorylation of tau of apolipoprotein E-deficient and control mice by M1 muscarinic agonist treatment.

    PubMed

    Genis, I; Fisher, A; Michaelson, D M

    1999-01-01

    Apolipoprotein E (apoE)-deficient mice have memory deficits that are associated with synaptic loss of basal forebrain cholinergic projections and with hyperphosphorylation of distinct epitopes of the microtubule-associated protein tau. Furthermore, treatment of apoE-deficient mice with the M1 selective agonist 1-methylpiperidine-4-spiro-(2'-methylthiazoline) [AF150(S)] abolishes their memory deficits and results in recovery of their brain cholinergic markers. In the present study, we used a panel of anti-tau monoclonal antibodies to further map the tau epitopes that are hyperphosphorylated in apoE-deficient mice and examined the effects of prolonged treatment with AF150(S). This revealed that tau of apoE-deficient mice contains a distinct, hyperphosphorylated "hot spot" domain which is localized N-terminally to the microtubule binding domain of tau, and that AF150(S) has an epitope-specific tau dephosphorylating effect whose magnitude is affected by apoE deficiency. Accordingly, epitopes which reside in the hyperphosphorylated "hot spot" are dephosphorylated by AF150(S) in apoE-deficient mice but are almost unaffected in the controls, whereas epitopes which flank this tau domain are dephosphorylated by AF150(S) in both mice groups. In contrast, epitopes located at the N and C terminals of tau are unaffected by AF150(S) in both groups of mice. These findings suggest that apoE deficiency results in hyperphosphorylation of a distinct tau domain whose excess phosphorylation can be reduced by muscarinic treatment.

  11. Quercetin improves macrophage reverse cholesterol transport in apolipoprotein E-deficient mice fed a high-fat diet.

    PubMed

    Cui, Yingjie; Hou, Pengbo; Li, Fahui; Liu, Qinghua; Qin, Shucun; Zhou, Guanghai; Xu, Xuelian; Si, Yanhong; Guo, Shoudong

    2017-01-14

    Quercetin, one of the most widely distributed flavonoids in plants, has been demonstrated to reduce hyperlipidaemia and atherosclerotic lesion formation. Reverse cholesterol transport (RCT) plays a crucial role in exporting cholesterol from peripheral cells, which is one mechanism utilized in the prevention and treatment of atherosclerosis. The aim of this study is to investigate whether quercetin reduces lipid accumulation by improving RCT in vivo. Apolipoprotein E-deficient mice fed a high-fat diet were used to investigate the effect of quercetin on RCT by an isotope tracing method, and the underlying mechanisms were clarified by molecular techniques. These novel results demonstrated that quercetin significantly improved [(3)H]-cholesterol transfer from [(3)H]-cholesterol-loaded macrophages to the plasma (approximately 34% increase), liver (30% increase), and bile (50% increase) and finally to the feces (approximately 40% increase) for excretion in apolipoprotein E-deficient mice fed a high-fat diet. Furthermore, quercetin markedly increased the cholesterol accepting ability of plasma and high-density lipoprotein (HDL) and dramatically decreased the content of malondialdehyde in plasma and oxidized phosphocholine carried by HDL. Therefore, the underlying mechanisms of quercetin in improving RCT may be partially due to the elevated cholesterol accepting ability of HDL, the increased expression levels of proteins related to RCT, such as ATP-binding cassettes (ABC) A1 and G1, and the improved antioxidant activity of HDL. Quercetin accelerates RCT in an atherosclerosis model, which is helpful in clarifying the lipid-lowering effect of quercetin.

  12. Sirt1 is involved in decreased bone formation in aged apolipoprotein E-deficient mice

    PubMed Central

    Hong, Wei; Xu, Xiao-ya; Qiu, Zhao-hui; Gao, Jian-jun; Wei, Zhan-ying; Zhen, Li; Zhang, Xiao-li; Ye, Zhi-bing

    2015-01-01

    Aim: Apolipoprotein E (ApoE) plays an important role in the transport and metabolism of lipids. Recent studies show that bone mass is increased in young apoE−/− mice. In this study we investigated the bone phenotype and metabolism in aged apoE−/− mice. Methods: Femurs and tibias were collected from 18- and 72-week-old apoE−/− mice and their age-matched wild-type (WT) littermates, and examined using micro-CT and histological analysis. Serum levels of total cholesterol, oxidized low-density lipoprotein (ox-LDL) and bone turnover markers were measured. Cultured bone mesenchymal stem cells (BMSCs) from tibias and femurs of 18-week-old apoE−/− mice were used in experiments in vitro. The expression levels of Sirt1 and Runx2 in bone tissue and BMSCs were measured using RT-PCR and Western blot analysis. Results: Compared with age-matched WT littermates, young apoE−/− mice exhibited high bone mass with increased bone formation, accompanied by higher serum levels of bone turnover markers OCN and TRAP5b, and higher expression levels of Sirt1, Runx2, ALP and OCN in bone tissue. In contrast, aged apoE−/− mice showed reduced bone formation and lower bone mass relative to age-matched WT mice, accompanied by lower serum OCN levels, and markedly reduced expression levels of Sirt1, Runx2, ALP and OCN in bone tissue. After BMSCs were exposed to ox-LDL (20 μg/mL), the expression of Sirt1 and Runx2 proteins was significantly increased at 12 h, and then decreased at 72 h. Treatment with the Sirt1 inhibitor EX527 (10 μmol/L) suppressed the expression of Runx2, ALP and OCN in BMSCs. Conclusion: In contrast to young apoE−/− mice, aged apoE−/− mice showe lower bone mass than age-matched WT mice. Long-lasting exposure to ox-LDL decreases the expression of Sirt1 and Runx2 in BMSCs, which may explain the decreased bone formation in aged apoE−/− mice. PMID:26592520

  13. Dietary blueberries sttenuate atherosclerosis in apolipoprotein E-deficient mice by upregulating antioxidant enzymes expression

    USDA-ARS?s Scientific Manuscript database

    Blueberries (BB) contain high levels of polyphenols and exhibit high antioxidant capacity. In this study, protective effects of BB against atherosclerosis and possible underlying mechanisms in reducing oxidative stress were examined in ApoE deficient (apoE-/-) mice. ApoE-/- mice were fed AIN-93G die...

  14. Proanthocyanidin Attenuation of Oxidative Stress and NF-κB Protects Apolipoprotein E-Deficient Mice against Diabetic Nephropathy

    PubMed Central

    Al-Malki, Abdulrahman L.; Sayed, Ahmed Amir Radwan; El Rabey, Haddad A.

    2013-01-01

    Hyperlipidemia and hyperglycemia result in oxidative stress and play a major role in the development of diabetic nephropathy (DN). We explored the effects of proanthocyanidin (PA) on the induction and progression of DN in apolipoprotein E-deficient mice. Diabetes Mellitus was induced in ten-week-old male apoE−/−mice using streptozotocin (STZ). Mice were fed with a high-fat diet in presence or absence of PA. PA treatment significantly reduced the high cholesterol levels, restored renal functions, and reduced albuminuria in the PA-treated diabetic mice compared with the diabetic untreated mice. In addition, the glomerular mesangial expansion in the diabetic mice was attenuated as a result of PA supplementation. Moreover, PA treatment restored the elevated levels of MDA and CML and the reduced activity of SOD and GSH in the diabetic mice. Furthermore, PA feeding reduced the activation and translocation of NF-κB to the nucleus compared with the diabetic untreated animals. Reduction of NF-κB activation resulted in the attenuation of the expression of IL-6, TGFβ, and RAGE which protected PA-treated mice against DN. The renoprotective effects of PA were found to be time independent regardless of whether the dietary feeding with PA was started pre-, co-, or post-STZ injection. In conclusion, part of the beneficial effects of PA includes the disruption of the detrimental AGE-RAGE-NFκB pathways. PMID:24023581

  15. Antiatherosclerotic and antioxidative effects of captopril in apolipoprotein E-deficient mice.

    PubMed

    Hayek, T; Attias, J; Smith, J; Breslow, J L; Keidar, S

    1998-04-01

    The effect of the angiotensin-converting enzyme (ACE) inhibitor, captopril, on the development of atherosclerosis was determined in the apolipoprotein (apo) E-deficient mice. These mice develop severe hypercholesterolemia and extensive atherosclerotic lesions on chow diet, similar to those found in humans. Furthermore, in these mice, accelerated atherosclerosis is associated with increased plasma lipid peroxidation, a phenomenon that may play a crucial role in the buildup of the atherosclerotic lesions. Mice received either placebo or 50 mg/kg/day of captopril. After 12 weeks of treatment, captopril reduced the aortic-lesion area by 70% compared with that of the placebo-treated group. Captopril also increased the resistance of low-density lipoprotein (LDL) to CuSO4-induced oxidative stress, as shown by a significant reduction in the LDL content of malondialdehyde (MDA) by 30%, as well as by the prolongation of the lag time required for LDL oxidation from 55 min in the placebo-treated mice to 70 min in the captopril-treated mice, and reduction of the maximum LDL oxidation at 150 min by 35%. In vitro studies demonstrated that preincubation of LDL with captopril, inhibited the onset of CuSO4-induced LDL peroxidation up to 120 min, and reduced the LDL content of MDA by 90%. We conclude that captopril attenuates atherosclerosis in the apo E-deficient mice, and this phenomenon may be related to its inhibitory effect on the plasma LDL oxidation.

  16. Cytochrome P450 1B1 Contributes to the Development of Atherosclerosis and Hypertension in Apolipoprotein E-Deficient Mice.

    PubMed

    Song, Chi Young; Ghafoor, Khuzema; Ghafoor, Hafiz U; Khan, Nayaab S; Thirunavukkarasu, Shyamala; Jennings, Brett L; Estes, Anne M; Zaidi, Sahar; Bridges, Dave; Tso, Patrick; Gonzalez, Frank J; Malik, Kafait U

    2016-01-01

    Cytochrome P450 (CYP) 1B1 contributes to vascular smooth muscle cell growth and hypertension in male mice. This study was conducted to determine the contribution of CYP1B1 to the development of atherosclerosis and hypertension and associated pathogenesis in 8-week-old male apolipoprotein E-deficient (ApoE(-/-)/Cyp1b1(+/+)), and ApoE- and CYP1B1-deficient (ApoE(-/-)/Cyp1b1(-/-)) mice fed a normal or atherogenic diet for 12 weeks. A separate group of ApoE(-/-)/Cyp1b1(+/+) mice on an atherogenic diet was injected every third day with the CYP1B1 inhibitor, 2,3',4,5'-tetramethoxystilbene (300 μg/kg), or its vehicle, dimethyl sulfoxide (30 μL, IP); systolic blood pressure was measured by the tail cuff method. After 12 weeks, mice were euthanized, blood collected for lipid analysis, and aortas harvested for measuring lesions and remodeling, and for infiltration of inflammatory cells by histological and immunohistochemical analysis, respectively, and for reactive oxygen species production. Blood pressure, areas of lipids and collagen deposition, elastin breaks, infiltration of macrophages and T lymphocytes, reactive oxygen species generation in the aorta, and plasma lipid levels were increased in ApoE(-/-)/Cyp1b1(+/+) mice on an atherogenic diet; these changes were minimized in mice given 2,3',4,5'-tetramethoxystilbene, and in ApoE(-/-)/Cyp1b1(-/-) mice on an atherogenic diet; absorption/production of lipids remained unaltered in these mice. These data suggest that aortic lesions, hypertension, and associated pathogenesis in ApoE(-/-)/Cyp1b1(+/+) mice on an atherogenic diet are most likely dependent on CYP1B1-generated oxidative stress and increased plasma lipid levels independent of blood pressure and absorption of lipids. CYP1B1 could serve as a novel target for developing drugs to treat atherosclerosis and hypertension caused by hypercholesterolemia.

  17. Nicotine Accelerates Atherosclerosis in Apolipoprotein E-Deficient Mice by Activating α7 Nicotinic Acetylcholine Receptor on Mast Cells.

    PubMed

    Wang, Chen; Chen, Han; Zhu, Wei; Xu, Yinchuan; Liu, Mingfei; Zhu, Lianlian; Yang, Fan; Zhang, Ling; Liu, Xianbao; Zhong, Zhiwei; Zhao, Jing; Jiang, Jun; Xiang, Meixiang; Yu, Hong; Hu, Xinyang; Lu, Hong; Wang, Jian'an

    2017-01-01

    Cigarette smoking is an independent risk factor for atherosclerosis. Nicotine, the addictive component of cigarettes, induces mast cell (MC) release and contributes to atherogenesis. The purpose of this study was to determine whether nicotine accelerates atherosclerosis through MC-mediated mechanisms and whether MC stabilizer prevents this pathological process. Nicotine administration increased the size of atherosclerotic lesions in apolipoprotein E-deficient (Apoe(-/-)) mice fed a fat-enriched diet. This was accompanied by enhanced intraplaque macrophage content and lipid deposition but reduced collagen and smooth muscle cell contents. MC deficiency in Apoe(-/-) mice (Apoe(-/-)Kit(W-sh/W-sh)) diminished nicotine-induced atherosclerosis. Nicotine activated bone marrow-derived MCs in vitro, which was inhibited by a MC stabilizer disodium cromoglycate or a nonselective nicotinic acetylcholine receptor blocker mecamylamine. Further investigation revealed that α7 nicotinic acetylcholine receptor was a target for nicotine activation in MCs. Nicotine did not change atherosclerotic lesion size of Apoe(-/-)Kit(W-sh/W-sh) mice reconstituted with MCs from Apoe(-/-)α7nAChR(-/-) animals. Activation of α7 nicotinic acetylcholine receptor on MCs is a mechanism by which nicotine enhances atherosclerosis. © 2016 American Heart Association, Inc.

  18. Dimethylarginine Dimethylaminohydrolase Overexpression Ameliorates Atherosclerosis in Apolipoprotein E-Deficient Mice by Lowering Asymmetric Dimethylarginine

    PubMed Central

    Jacobi, Johannes; Maas, Renke; Cardounel, Arturo J.; Arend, Michaela; Pope, Arthur J.; Cordasic, Nada; Heusinger-Ribeiro, Juliane; Atzler, Dorothee; Strobel, Joachim; Schwedhelm, Edzard; Böger, Rainer H.; Hilgers, Karl F.

    2010-01-01

    Asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase, is increasingly recognized as a novel biomarker in cardiovascular disease. To date, it remains unclear whether elevated ADMA levels are merely associated with cardiovascular risk or whether this molecule is of functional relevance in the pathogenesis of atherosclerotic vascular disease. To clarify this issue, we crossed dimethylarginine dimethylaminohydrolase (DDAH) transgenic mice that overexpress the human isoform 1 of the ADMA degrading enzyme DDAH into ApoE-deficient mice to generate ApoE−/−/hDDAH1+/− mice. In these mice, as well as ApoE−/− wild-type littermates, atherosclerosis within the aorta as well as vascular function of aortic ring preparations was assessed. We report here that overexpression of hDDAH1 reduces plaque formation in ApoE−/− mice by lowering ADMA. The extent of atherosclerosis closely correlated with plasma ADMA levels in male but not female mice fed either a standard rodent chow or an atherogenic diet. Functional analysis of aortic ring preparations revealed improved endothelial function in mice overexpressing hDDAH1. Our findings provide proof-of-principle that ADMA plays a causal role as a culprit molecule in atherosclerosis and support recent evidence indicating a functional relevance of DDAH enzymes in genetic mouse models. Together, these results demonstrate that pharmacological interventions targeting the ADMA/DDAH pathway may represent a novel approach in the prevention and management of cardiovascular diseases. PMID:20348244

  19. Angiopoietin-2 attenuates angiotensin II-induced aortic aneurysm and atherosclerosis in apolipoprotein E-deficient mice

    PubMed Central

    Yu, Hongyou; Moran, Corey S.; Trollope, Alexandra F.; Woodward, Lynn; Kinobe, Robert; Rush, Catherine M.; Golledge, Jonathan

    2016-01-01

    Angiogenesis and inflammation are implicated in aortic aneurysm and atherosclerosis and regulated by angiopoietin-2 (Angpt2). The effect of Angpt2 administration on experimental aortic aneurysm and atherosclerosis was examined. Six-month-old male apolipoprotein E deficient (ApoE−/−) mice were infused with angiotensin II (AngII) and administered subcutaneous human Fc-protein (control) or recombinant Angpt2 (rAngpt2) over 14 days. Administration of rAngpt2 significantly inhibited AngII-induced aortic dilatation and rupture of the suprarenal aorta (SRA), and development of atherosclerosis within the aortic arch. These effects were blood pressure and plasma lipoprotein independent and associated with Tie2 activation and down-regulation of monocyte chemotactic protein-1 (MCP-1) within the SRA. Plasma concentrations of MCP-1 and interleukin-6 were significantly lower in mice receiving rAngpt2. Immunostaining for the monocyte/macrophage marker MOMA-2 and the angiogenesis marker CD31 within the SRA were less in mice receiving rAngpt2 than controls. The percentage of inflammatory (Ly6Chi) monocytes within the bone marrow was increased while that in peripheral blood was decreased by rAngpt2 administration. In conclusion, administration of rAngpt2 attenuated angiotensin II-induced aortic aneurysm and atherosclerosis in ApoE−/− mice associated with reduced aortic inflammation and angiogenesis. Up-regulation of Angpt2 may have potential therapeutic value in patients with aortic aneurysm and atherosclerosis. PMID:27767064

  20. Vitamin D Deficiency and Exogenous Vitamin D Excess Similarly Increase Diffuse Atherosclerotic Calcification in Apolipoprotein E Knockout Mice

    PubMed Central

    Ellam, Timothy; Hameed, Abdul; ul Haque, Risat; Muthana, Munitta; Wilkie, Martin; Francis, Sheila E.; Chico, Timothy J. A.

    2014-01-01

    Background Observational data associate lower levels of serum vitamin D with coronary artery calcification, cardiovascular events and mortality. However, there is little interventional evidence demonstrating that moderate vitamin D deficiency plays a causative role in cardiovascular disease. This study examined the cardiovascular effects of dietary vitamin D deficiency and of vitamin D receptor agonist (paricalcitol) administration in apolipoprotein E knockout mice. Methods Mice were fed atherogenic diets with normal vitamin D content (1.5IU/kg) or without vitamin D. Paricalcitol, or matched vehicle, was administered 3× weekly by intraperitoneal injection. Following 20 weeks of these interventions cardiovascular phenotype was characterized by histological assessment of aortic sinus atheroma, soluble markers, blood pressure and echocardiography. To place the cardiovascular assessments in the context of intervention effects on bone, structural changes at the tibia were assessed by microtomography. Results Vitamin D deficient diet induced significant reductions in plasma vitamin D (p<0.001), trabecular bone volume (p<0.01) and bone mineral density (p<0.005). These changes were accompanied by an increase in calcification density (number of calcifications per mm2) of von Kossa-stained aortic sinus atheroma (461 versus 200, p<0.01). Paricalcitol administration suppressed parathyroid hormone (p<0.001), elevated plasma calcium phosphate product (p<0.005) and induced an increase in calcification density (472 versus 200, p<0.005) similar to that seen with vitamin D deficiency. Atheroma burden, blood pressure, metabolic profile and measures of left ventricular hypertrophy were unaffected by the interventions. Conclusion Vitamin D deficiency, as well as excess, increases atherosclerotic calcification. This phenotype is induced before other measures of cardiovascular pathology associated clinically with vitamin D deficiency. Thus, maintenance of an optimal range of vitamin D

  1. Silencing of Anticoagulant Protein C Evokes Low-Incident but Spontaneous Atherothrombosis in Apolipoprotein E-Deficient Mice-Brief Report.

    PubMed

    Ouweneel, Amber B; Heestermans, Marco; Verwilligen, Robin A F; Gijbels, Marion J J; Reitsma, Pieter H; Van Eck, Miranda; van Vlijmen, Bart J M

    2017-05-01

    Murine atherosclerosis models do not spontaneously develop atherothrombotic complications. We investigated whether disruption of natural anticoagulation allows preexisting atherosclerotic plaques to progress toward an atherothrombotic phenotype. On lowering of plasma protein C levels with small interfering RNA (siProc) in 8-week Western-type diet-fed atherosclerotic apolipoprotein E-deficient mice, 1 out of 4 mice displayed a large, organized, and fibrin- and leukocyte-rich thrombus on top of an advanced atherosclerotic plaque located in the aortic root. Although again at low incidence (3 in 25), comparable thrombi at the same location were observed during a second independent experiment in 9-week Western-type diet-fed apolipoprotein E-deficient mice. Mice with thrombi on their atherosclerotic plaques did not show other abnormalities and had equally lowered plasma protein C levels as siProc-treated apolipoprotein E-deficient mice without thrombi. Fibrinogen and thrombin-antithrombin concentrations and blood platelet numbers were also comparable, and plaques in siProc mice with thrombi had a similar composition and size as plaques in siProc mice without thrombi. Seven out of 25 siProc mice featured clots in the left atrium of the heart. Our findings indicate that small interfering RNA-mediated silencing of protein C in apolipoprotein E-deficient mice creates a condition that allows the occurrence of spontaneous atherothrombosis, albeit at a low incidence. Lowering natural anticoagulation in atherosclerosis models may help to discover factors that increase atherothrombotic complications. © 2017 American Heart Association, Inc.

  2. Tongxinluo mitigates atherogenesis by regulating angiogenic factors and inhibiting vasa vasorum neovascularization in apolipoprotein E-deficient mice

    PubMed Central

    Ma, Lianyue; Ni, Mei; Hao, Panpan; Lu, Huixia; Yang, Xiaoyan; Xu, Xingli; Zhang, Cheng; Huang, Shanying; Zhao, Yuxia; Liu, Xiaoling; Zhang, Yun

    2016-01-01

    Vasa vasorum (VV) neovascularization contributes to atherogenesis and its expansion and distribution is correlated with intraplaque expression of angiogenic factors. The present study investigated the roles of Tongxinluo (TXL), a traditional Chinese medication, on VV proliferation and atherogenesis. In vitro, TXL pre-treatment reversed the tumor necrosis factor-a (TNF-a) induced expression of vascular endothelial growth factor A (VEGF-A) and angiopoietin-1 (ANGPT-1) but not ANGPT-2, leading to increased ratio of ANGPT-1 to ANGPT-2. Consistently, TXL treatment (at a dosage of 0.38, 0.75, 1.5 g/kg/d, respectively) decreased the expression of VEGF-A while increased that of ANGPT-1 in early atherosclerotic lesions of apolipoprotein E deficient (apoE−/−) mice. On aortic ring assay, microvessels sprouting from aortas were significantly inhibited in TXL-treated mice. Moreover, VV neovascularization in plaques was markedly reduced with TXL treatment. Histological and morphological analysis demonstrated that TXL treatment reduced plaque burden, plaque size and changed the plaque composition. These data suggest that TXL inhibits early atherogenesis through regulating angiogenic factor expression and inhibiting VV proliferation in atherosclerotic plaque. Our study shed new light on the anti-atherosclerotic effect of TXL. PMID:26908443

  3. Comprehensive Plasma Metabolomic Analyses of Atherosclerotic Progression Reveal Alterations in Glycerophospholipid and Sphingolipid Metabolism in Apolipoprotein E-deficient Mice

    PubMed Central

    Dang, Vi T.; Huang, Aric; Zhong, Lexy H.; Shi, Yuanyuan; Werstuck, Geoff H.

    2016-01-01

    Atherosclerosis is the major underlying cause of most cardiovascular diseases. Despite recent advances, the molecular mechanisms underlying the pathophysiology of atherogenesis are not clear. In this study, comprehensive plasma metabolomics were used to investigate early-stage atherosclerotic development and progression in chow-fed apolipoprotein E-deficient mice at 5, 10 and 15 weeks of age. Comprehensive plasma metabolomic profiles, based on 4365 detected metabolite features, differentiate atherosclerosis-prone from atherosclerosis-resistant models. Metabolites in the sphingomyelin pathway were significantly altered prior to detectable lesion formation and at all subsequent time-points. The cytidine diphosphate-diacylglycerol pathway was up-regulated during stage I of atherosclerosis, while metabolites in the phosphatidylethanolamine and glycosphingolipid pathways were augmented in mice with stage II lesions. These pathways, involving glycerophospholipid and sphingolipid metabolism, were also significantly affected during the course of atherosclerotic progression. Our findings suggest that distinct plasma metabolomic profiles can differentiate the different stages of atherosclerotic progression. This study reveals that alteration of specific, previously unreported pathways of glycerophospholipid and sphingolipid metabolism are associated with atherosclerosis. The clear difference in the level of several metabolites supports the use of plasma lipid profiling as a diagnostic tool of atherogenesis. PMID:27721472

  4. Chicory, a typical vegetable in Mediterranean diet, exerts a therapeutic role in established atherosclerosis in apolipoprotein E-deficient mice.

    PubMed

    Lin, Weiqun; Liu, Chaoqun; Yang, Hai; Wang, Wenting; Ling, Wenhua; Wang, Dongliang

    2015-09-01

    Since protocatechuic acid exerts an atheroprotective role, we investigated how chicory (Cichorium intybus L. var. foliosum, Belgian endive) rich in protocatechuic acid, a typical vegetable in Mediterranean diet, affects preestablished atherosclerosis progression. Apolipoprotein E-deficient mice fed AIN diets containing 0.5% freeze-dried chicory for 10 weeks displayed a reduction in lesion size with a concomitant improvement in lesion stability indicated by fewer macrophages and more collagen content. Chicory consumption suppressed aortic cholesterol accumulation and intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and monocyte chemoattractant protein-1 expression, whereas it increased aortic ATP-binding cassette transporter A1 (ABCA1) and G1 (ABCG1) expression. Furthermore, chicory consumption improved peritoneal macrophage phenotype with less cellular cholesterol associated with an enhancement of cholesterol efflux capacity through upregulation of ABCA1 and ABCG1, less cellular oxidative stress associated with an inhibition of nicotinamide adenine dinucleotide phosphate oxidase activity, and weaker inflammatory responses associated with an inhibition of nuclear factor-κB activation. Interestingly, ABCA1 and ABCG1 silencing tended to completely block beneficial effects of chicory in peritoneal macrophages. Chicory exerts an atheroprotective role in mice possibly by regulating lesional macrophage content and phenotype, suggesting that chicory is one underrated contributor to Mediterranean Diet-induced atheroprotection. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. P-selectin expressed by a human SELP transgene is atherogenic in apolipoprotein E-deficient mice

    PubMed Central

    Zhang, Nan; Liu, Zhenghui; Yao, Longbiao; Mehta-D’souza, Padmaja; McEver, Rodger P.

    2016-01-01

    Objective During inflammation, P-selectin expressed on activated endothelial cells and platelets mediates rolling adhesion of leukocytes. Atherosclerosis-prone mice crossed with P-selectin-deficient (Selp−/−) mice develop smaller lesions. Cytokines such as tumor necrosis factor-α increase Selp transcripts and augment atherosclerosis in mice. However, they decrease SELP transcripts in humans, challenging assumptions that human P-selectin is atherogenic. We used mice expressing a human SELP transgene to examine the atherogenic role of P-selectin. Approach and results We crossed apolipoprotein E-deficient (Apoe−/−) mice with Selp−/− mice and/or transgenic mice expressing the entire human SELP gene (TgSELP+/−). Aortas developed larger, macrophage-rich atheromas in Apoe−/−Selp−/−TgSELP+/− mice than in Apoe−/−Selp−/− mice after 8 or 16 weeks on a Western diet. Confocal microscopy of Apoe−/−Selp−/−TgSELP+/− aortas revealed staining for human P-selectin in endothelial cells overlying atheromas, but not in lesional macrophages. We also observed staining for human P-selectin in aortic endothelial cells of 3–4-week-old Apoe−/−Selp−/−TgSELP+/− weanlings before atheromas developed. Furthermore, human SELP transcripts were ~3-fold higher in aortas of Apoe−/−Selp+/−TgSELP+/− weanlings than in Selp+/−TgSELP+/− weanlings, whereas murine Selp and Sele transcripts were equivalent in weanlings of both genotypes. Human SELP transcripts in aortas of Apoe−/−Selp+/−TgSELP+/− mice remained nearly constant during 16 weeks on a Western diet, whereas murine Selp and Sele transcripts progressively increased. Bone marrow transplantation in Apoe−/−Selp−/− and Apoe−/−Selp−/−TgSELP+/− mice demonstrated that both platelets and endothelial cells must express human P-selectin to promote atherogenesis. Conclusions P-selectin expressed by human SELP is atherogenic in Apoe−/− mice, suggesting that P

  6. Dipeptidyl peptidase-4 inhibitor, linagliptin, ameliorates endothelial dysfunction and atherogenesis in normoglycemic apolipoprotein-E deficient mice.

    PubMed

    Salim, Hotimah Masdan; Fukuda, Daiju; Higashikuni, Yasutomi; Tanaka, Kimie; Hirata, Yoichiro; Yagi, Shusuke; Soeki, Takeshi; Shimabukuro, Michio; Sata, Masataka

    2016-04-01

    Dipeptidyl peptidase-4 (DPP-4) inhibitors have vasoprotective effects. This study investigated whether a recently approved DPP-4 inhibitor, linagliptin (Lina), suppresses atherogenesis in non-diabetic apolipoprotein-E deficient (ApoE(-/-)) mice, and examined its effects on endothelial function. Lina (10mg/kg/day) was administered orally to ApoE(-/-) mice for 20 weeks. Lina reduced atherogenesis without alteration of metabolic parameters including blood glucose level compared with control (P<0.05). Results of immunohistochemical analyses and quantitative RT-PCR demonstrated that Lina significantly decreased inflammatory molecule expression and macrophage infiltration in the atherosclerotic aorta. Lina administration to ApoE(-/-) mice for 9 weeks ameliorated endothelium-dependent vasodilation compared with that in untreated mice. Plasma active glucagon-like peptide-1 (GLP-1) level was significantly higher in the treated group (P<0.05). Exendin-4 (Ex-4), a GLP-1 analog, ameliorated endothelium-dependent vasodilation impaired by palmitic acid (PA) in wild-type mouse aortic segments. Ex-4 promoted phosphorylation of eNOS(Ser1177) and Akt, both of which were abrogated by PA, in human umbilical vein endothelial cells. In addition, Lina administration to ApoE(-/-) mice decreased oxidative stress, as determined by urinary 8-OHdG secretion and NADPH oxidase subunit expression in the abdominal aorta. Lina inhibited atherogenesis in non-diabetic ApoE(-/-) mice. Amelioration of endothelial dysfunction associated with a reduction of oxidative stress by GLP-1 contributes to the atheroprotective effects of Lina. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Nuclear microprobe investigation into the trace elemental contents of carotid artery walls of apolipoprotein E deficient mice

    NASA Astrophysics Data System (ADS)

    Minqin, Ren; En, Huang; Beck, Konstanze; Rajendran, Reshmi; Wu, Ben J.; Halliwell, Barry; Watt, Frank; Stocker, Roland

    2007-07-01

    Atherosclerosis is a progressive disease that causes lesions in large and medium-sized arteries. There is increasing evidence that the function of vascular endothelial cells is impaired by oxidation reactions, and that metal ions may participate in these processes. The nuclear microscopy facility in NUS, which has the ability to focus a 2 MeV proton beam down to sub micron spot sizes, was used to investigate the trace elemental changes (e.g. Zn and Fe) in atherosclerotic lesions in the common carotid artery of apolipoprotein E deficient mice fed a high fat diet. In this preliminary study, which is part of a larger study to investigate the effects of probucol on carotid artery atherosclerosis, two sets of mice were used; a test set fed a high fat diet +1% probucol, and a control set which was fed a high fat diet only. The results show that the Zn/Fe ratio was significantly higher in the media of arteries of probucol treated animals without overlying lesion (4.3) compared to the media with overlying lesion (1.3) ( p = 0.004) for test mice. For the control mice, the arterial Zn/Fe ratio was 1.8 for media without overlying lesion, compared with 1.0 for media with overlying lesion ( p = 0.1). Thus, for media without overlying lesion, the Zn/Fe ratio was significantly higher ( p = 0.009) in probucol-treated (4.3) than control mice (1.8), whereas there was little difference in the ratios between the two groups in media with overlying lesion (1.3 compared with 1.0). These preliminary results are consistent with the idea that the levels of iron and zinc concentrations within the artery wall may influence the formation of atherosclerotic plaque in the carotid artery.

  8. The continuous administration of aspirin attenuates atherosclerosis in apolipoprotein E-deficient mice.

    PubMed

    Paul, A; Calleja, L; Camps, J; Osada, J; Vilella, E; Ferré, N; Mayayo, E; Joven, J

    2000-12-15

    Aspirin reduces the incidence of thrombotic occlusive events. Classically this has been thought to be due to the platelet inhibitory action of aspirin but it has recently been shown that inflammation plays a predominant role in the initiation and progression of lesions in atherosclerosis. In humans, treatment with aspirin reduces cardiovascular risk and slows carotid plaque growth in a dose-dependent fashion. We have explored this issue in Apo E-deficient mice on a high-fat, high cholesterol diet which provided these animals with a continuous administration of 500 microg/day of acetylsalicylic acid in the drinking water. After 10 weeks of treatment, the size of the atherosclerotic lesion at the aortic sinus had reduced by 35%. At the end of the trial there were no significant changes in either plasma lipids or in the quantitative distribution among lipoproteins. Likewise, the total antioxidant status and the resistance of plasma to oxidation in vitro was similar and there was no change in the distribution of iron deposits and in the relative composition of plasma pro-oxidants and antioxidants, or in the concentration of plasma in ferritin. Therefore, it is our hypothesis that the antiinflammatory effect is responsible for the reduction in lesion size. We propose that antiinflammatory molecules which do not cause gastrointestinal complications should be tested in humans to determine long-term efficacy in the attenuation of atherosclerosis.

  9. Copper Chelation by Tetrathiomolybdate Inhibits Vascular Inflammation and Atherosclerotic Lesion Development in Apolipoprotein E-deficient Mice

    PubMed Central

    Wei, Hao; Zhang, Wei-Jian; Mcmillen, Timothy S.; Leboeuf, Renee C.; Frei, Balz

    2012-01-01

    Endothelial activation, which is characterized by upregulation of cellular adhesion molecules and pro-inflammatory chemokines and cytokines, and consequent monocyte recruitment to the arterial intima are etiologic factors in atherosclerosis. Redox-active transition metal ions, such as copper and iron, may play an important role in endothelial activation by stimulating redox-sensitive cell signaling pathways. We have shown previously that copper chelation by tetrathiomolybdate (TTM) inhibits LPS-induced acute inflammatory responses in vivo. Here, we investigated whether TTM can inhibit atherosclerotic lesion development in apolipoprotein E-deficient (apoE−/−) mice. We found that 10-week treatment of apoE−/− mice with TTM (33–66 ppm in the diet) reduced serum levels of the copper-containing protein, ceruloplasmin, by 47%, and serum iron by 26%. Tissue levels of “bioavailable” copper, assessed by the copper-to-molybdenum ratio, decreased by 80% in aorta and heart, whereas iron levels of these tissues were not affected by TTM treatment. Furthermore, TTM significantly attenuated atherosclerotic lesion development in whole aorta by 25% and descending aorta by 45% compared to non-TTM treated apoE−/− mice. This anti-atherogenic effect of TTM was accompanied by several anti-inflammatory effects, i.e., significantly decreased serum levels of soluble vascular cell and intercellular adhesion molecules (VCAM-1 and ICAM-1); reduced aortic gene expression of VCAM-1, ICAM-1, monocyte chemotactic protein-1, and pro-inflammatory cytokines; and significantly less aortic accumulation of M1 type macrophages. In contrast, serum levels of oxidized LDL were not reduced by TTM. These data indicate that TTM inhibits atherosclerosis in apoE−/− mice by reducing bioavailable copper and vascular inflammation, not by altering iron homeostasis or reducing oxidative stress. PMID:22770994

  10. Is hyperuricemia a risk factor for arteriosclerosis? Uric acid and arteriosclerosis in apolipoprotein e-deficient mice.

    PubMed

    Wakuda, Hirokazu; Uchida, Shinya; Ikeda, Masahiko; Tabuchi, Masaki; Akahoshi, Yasumitsu; Shinozuka, Kazumasa; Yamada, Shizuo

    2014-01-01

    Although hyperlipidemia, high blood pressure, and diabetes increase the risk of arteriosclerosis, it is not clear whether hyperuricemia increases the risk of arteriosclerosis or not. We examined the effects of uric acid and curative drugs for hyperuricemia on atherosclerosis-susceptible C57BL/6J apolipoprotein E-deficient (apoE(-/-)) mice. Male apoE(-/-) mice (age: 6 weeks) were fed a normal diet (normal diet group) or a uric acid-enriched diet. Mice fed the uric acid-enriched diet were divided into three groups and administered a drinking vehicle (high uric acid diet group), allopurinol (20 mg·kg(-1)·d(-1)), or benzbromarone (20 mg·kg(-1)·d(-1)) for 10 weeks. Serum uric acid concentrations were higher in the high uric acid diet group than in the normal diet group, and concentrations in the allopurinol and benzbromarone groups were lower than in the high uric acid diet group. Serum total cholesterol and triglyceride levels were lower in the allopurinol group than in the high uric acid diet group. Oxidative stress was lower in the benzbromarone group than in the high uric acid diet group. Atherosclerotic lesion areas were smaller in the allopurinol and benzbromarone groups than in the high uric acid diet group. Thus, hyperuricemia may not be an independent risk factor for arteriosclerosis; however, the administration of allopurinol and benzbromarone prevented the development of atherosclerosis in apoE(-/-) mice fed a uric acid-enriched diet. The anti-atherosclerotic effect was in part due to lower total cholesterol and oxidative stress in the serum. Other possible mechanisms underlying this effect should be investigated.

  11. Aerobic Exercise Suppresses Atherosclerosis Through Adiponectin-Nuclear Transcription Factor κB Pathway in Apolipoprotein E-deficient Mice.

    PubMed

    Wu, Weidong; Wang, Haiying; Jiao, Guangfa; Yue, Jingjing; Wang, Guowei

    2017-03-01

    We aimed to investigate the therapeutic effect of aerobic exercise on atherosclerosis (AS) in apolipoprotein E-deficient mice and the adiponectin (ApN)-nuclear transcription factor κB (NF-κB) pathway involved in the related anti-inflammation. ApoE-deficient mice with AS (AS+C), and ApoE-deficient mice with AS and aerobic exercise (AS+E) were investigated for body weight and visceral fat. Pathomorphology of the aortic vascular wall was qualitatively and quantitatively evaluated with hematoxylin-eosin staining. The ApN messenger RNA level in adipose tissue and ApN level in plasma were determined. The aortic adiponectin receptor 1 (AdipoR1) and NF-κB levels were determined with western blot. There was no significant difference in body weight between the AS+C and the AS+E groups, but visceral fat in the AS+E group was significantly smaller than that in the AS+C group. Aortic vascular wall fiber board in the AS+C group broke, but this aortic disease in the AS+E group was obviously alleviated. The AS+E group showed a smaller neointimal hyperplasia and plaque area compared with AS+C group. After a high-fat diet, the ApN levels in both adipose tissue and plasma were decreased in the AS+C group and returned to a relative high level in the AS+E group. The expression of AdipoR1 protein in the AS+C group was significantly lower than those in the AS+E group. As for NF-κB protein, its enhanced expression in the AS+C group was reversed to a relatively low level in the AS+E group. Aerobic exercise suppressed AS through the ApN-NF-κB pathway in ApoE-deficient mice. Copyright © 2017 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.

  12. The effects of direct thrombin inhibition with dabigatran on plaque formation and endothelial function in apolipoprotein E-deficient mice.

    PubMed

    Lee, Illkyu-O; Kratz, Mario T; Schirmer, Stephan H; Baumhäkel, Magnus; Böhm, Michael

    2012-11-01

    The recently developed oral anticoagulant dabigatran (Dabi) etexilate directly inhibits thrombin after activation by plasma esterases to dabigatran. Thrombin is involved in the pathogenesis of atherosclerosis. We investigated the effects of direct thrombin inhibition on atherosclerosis and endothelial function in a hypercholesterolemic mouse model with accelerated atherosclerosis {[apolipoprotein E-deficient (ApoE(-/-)] mice}. ApoE(-/-) mice were treated with a cholesterol-rich diet for 12 weeks and either dabigatran etexilate (900 mg/kg body weight) or vehicle. Wild-type (C57/B6) mice served as control. Endothelial function was assessed with carbachol (endothelium dependent) by using glyceroltrinitrate (endothelium independent) as control in aortic rings. Atherosclerotic lesion formation was evaluated with Oil Red staining, and vascular collagen content was determined by Sirius Red staining. Reactive oxygen species (ROS) production was determined by semiquantitative immunohistochemical staining. Measurement of dabigatran plasma levels (622.3±169 ng/ml) and a performed coagulation test (diluted thrombin time) revealed a relevant anticoagulatory concentration. Dabigatran etexilate attenuated increased atherosclerotic plaque formation [ApoE(-/-) Dabi: 16.1±3.8% of ApoE(-/-) control; p<0.001], decreased collagen content [ApoE(-/-) Dabi: 49.1±10% of ApoE(-/-) control; p=0.01], and ROS production in dihydroethidium staining [ApoE(-/-) Dabi: 46.3±5.4% of ApoE(-/-) control; p=0.005] in parallel to an improvement of endothelial function [ApoE(-/-) control 42.6±2.7 versus ApoE(-/-) Dabi 62.9±3.3% of phenylephrine-induced contraction; p=0.001] at 100 μmol carbachol. These data suggest that direct thrombin inhibition in a relevant dosage improved endothelial function and reduced atherosclerotic lesion size, collagen content, and oxidative stress in hypercholesterolemic atherosclerosis. Interference with the coagulation system might provide a therapeutic target to

  13. Inhibition of endoplasmic reticulum stress and atherosclerosis by 2-aminopurine in apolipoprotein e-deficient mice.

    PubMed

    Zhou, Lichun; Yang, Dezhi; Wu, Dong Fang; Guo, Zhong Mao; Okoro, Emmanuel; Yang, Hong

    2013-01-01

    We previously reported that the apolipoprotein (apo) B48-carrying lipoproteins obtained from apoE knockout (apoE (-/-) ) mice, so called E(-)/B48 lipoproteins, transformed mouse macrophages into foam cells and enhanced the phosphorylation of eukaryotic translation initiation factor 2 α (eIF-2 α ). Furthermore, the eIF-2 α phosphorylation inhibitor, 2-aminopurine (2-AP), attenuated E(-)/B48 lipoprotein-induced foam cell formation. The present report studied the effect of 2-AP on atherosclerosis in apoE (-/-) mice. Our results showed that the level of food intake, bodyweight, plasma cholesterol, and triglycerides was comparable in apoE (-/-) mice treated with or without 2-AP. However, the mean size of atherosclerotic lesions in the aorta sinus as well as the surface area of the entire aorta of 2-AP-treated apoE (-/-) mice were reduced by about 55% and 39%, respectively, compared to samples from untreated control apoE (-/-) mice. In addition, the 2-AP-treated apoE (-/-) mice showed a significant decrease in glucose-regulated protein 78 (GRP78) and phosphorylated eIF-2 α in their aortic samples as compared to levels in untreated control apoE (-/-) mice. These observations suggest that endoplasmic reticulum stress is a causal mechanism for the development of atherosclerosis in apoE (-/-) mice and that therapeutic strategies can be developed for using eIF-2 α phosphorylation inhibitors, such as 2-AP, to prevent or treat atherosclerosis.

  14. The endogenous estradiol metabolite 2-methoxyestradiol reduces atherosclerotic lesion formation in female apolipoprotein E-deficient mice.

    PubMed

    Bourghardt, Johan; Bergström, Göran; Krettek, Alexandra; Sjöberg, Sara; Borén, Jan; Tivesten, Asa

    2007-09-01

    Estradiol, the major endogenous estrogen, reduces experimental atherosclerosis and metabolizes to 2-methoxyestradiol in vascular cells. Currently undergoing evaluation in clinical cancer trials, 2-methoxyestradiol potently inhibits cell proliferation independently of the classical estrogen receptors. This study examined whether 2-methoxyestradiol affects atherosclerosis development in female mice. Apolipoprotein E-deficient mice, a well-established mouse model of atherosclerosis, were ovariectomized and treated through slow-release pellets with placebo, 17beta-estradiol (6 microg/d), or 2-methoxyestradiol [6.66 microg/d (low-dose) or 66.6 microg/d (high-dose)]. After 90 d, body weight gain decreased and uterine weight increased in the high-dose but not low-dose 2-methoxyestradiol group. En face analysis showed that the fractional area of the aorta covered by atherosclerotic lesions decreased in the high-dose 2-methoxyestradiol (52%) but not in the low-dose 2-methoxyestradiol group. Total serum cholesterol levels decreased in the high- and low-dose 2-methoxyestradiol groups (19%, P < 0.05 and 21%, P = 0.062, respectively). Estradiol treatment reduced the fractional atherosclerotic lesion area (85%) and decreased cholesterol levels (42%). In conclusion, our study shows for the first time that 2-methoxyestradiol reduces atherosclerotic lesion formation in vivo. The antiatherogenic activity of an estradiol metabolite lacking estrogen receptor activating capacity may argue that trials on cardiovascular effects of hormone replacement therapy should use estradiol rather than other estrogens. Future research should define the role of 2-methoxyestradiol as a mediator of the antiatherosclerotic actions of estradiol. Furthermore, evaluation of the effects of 2-methoxyestradiol on cardiovascular disease endpoints in ongoing clinical trials is of great interest.

  15. Inhibition of Endoplasmic Reticulum Stress and Atherosclerosis by 2-Aminopurine in Apolipoprotein E-Deficient Mice

    PubMed Central

    Zhou, Lichun; Yang, Dezhi; Wu, Dong Fang; Guo, Zhong Mao; Yang, Hong

    2013-01-01

    We previously reported that the apolipoprotein (apo) B48-carrying lipoproteins obtained from apoE knockout (apoE−/−) mice, so called E−/B48 lipoproteins, transformed mouse macrophages into foam cells and enhanced the phosphorylation of eukaryotic translation initiation factor 2α (eIF-2α). Furthermore, the eIF-2α phosphorylation inhibitor, 2-aminopurine (2-AP), attenuated E−/B48 lipoprotein-induced foam cell formation. The present report studied the effect of 2-AP on atherosclerosis in apoE−/− mice. Our results showed that the level of food intake, bodyweight, plasma cholesterol, and triglycerides was comparable in apoE−/− mice treated with or without 2-AP. However, the mean size of atherosclerotic lesions in the aorta sinus as well as the surface area of the entire aorta of 2-AP-treated apoE−/− mice were reduced by about 55% and 39%, respectively, compared to samples from untreated control apoE−/− mice. In addition, the 2-AP-treated apoE−/− mice showed a significant decrease in glucose-regulated protein 78 (GRP78) and phosphorylated eIF-2α in their aortic samples as compared to levels in untreated control apoE−/− mice. These observations suggest that endoplasmic reticulum stress is a causal mechanism for the development of atherosclerosis in apoE−/− mice and that therapeutic strategies can be developed for using eIF-2α phosphorylation inhibitors, such as 2-AP, to prevent or treat atherosclerosis. PMID:23984090

  16. StAR overexpression decreases serum and tissue lipids in apolipoprotein E-deficient mice

    PubMed Central

    Ning, Yanxia; Xu, Leyuan; Ren, Shunlin; Pandak, William M.; Chen, Sifeng; Yin, Lianhua

    2010-01-01

    Cholesterol metabolism as initiated by mitochondrial CYP27A1 is a ubiquitous pathway capable of synthesizing multiple key regulatory oxysterols involved in lipids homeostasis. Previously we have shown that the regulation of its activities within hepatocytes is highly controlled by the rate of mitochondrial cholesterol delivery. In the present study, we hypothesized that increasing expression of the mitochondrial cholesterol delivery protein, StAR, is able to lower lipids accumulation in liver, aortic wall, as well as in serum in a well-documented animal model, apoE−/− mice. ApoE−/− mice, characterized by increased serum, liver, and endothelial cholesterol and triglyceride levels by 3 months of age, were infected with recombinant CMV-StAR adenovirus to increase StAR protein expression. Six days following infection, serum total cholesterol and triglycerides had decreased 19 % (P<0.01) and 30% (P<0.01), respectively, with a compensatory 40% (P<0.01) increase in serum HDL-cholesterol in increased StAR expressing mice as compared to controls (no or control virus). Histologic and biochemical analysis of the liver demonstrated not only a dramatic decrease in cholesterol (↓25%; P<0.01), but an even more marked decrease in triglyceride (↓56%; P<0.01) content. En bloc Sudan IV staining of the aorta revealed a >80% (P<0.01) decrease in neutral lipid staining. This study demonstrates for the first time a possible therapeutic role of the CYP27A1–initiated pathway in the treatment of dyslipidemias. PMID:19373502

  17. Cannabidiol-2',6'-dimethyl ether stimulates body weight gain in apolipoprotein E-deficient BALB/c. KOR/Stm Slc-Apoe(shl) mice.

    PubMed

    Takeda, Shuso; Hirota, Rena; Teradaira, Sari; Takeda-Imoto, Masumi; Watanabe, Kazuhito; Toda, Akihisa; Aramaki, Hironori

    2015-12-01

    The biological activities of cannabidiol (CBD), a major non-psychotropic constituent of the fiber-type cannabis plant, have been examined in detail (e.g., CBD modulation of body weight in mice and rats). However, few studies have investigated the biological activities of cannabidiol-2',6'-dimethyl ether (CBDD), a dimethyl ether derivative of the parent CBD. We herein focused on the effects of CBDD on body weight changes in mice, and demonstrated that it stimulated body weight gain in apolipoprotein E (ApoE)-deficient BALB/c. KOR/Stm Slc-Apoe(shl) mice, especially between 10 and 20 weeks of age.

  18. Combination of n-3 polyunsaturated fatty acids reduces atherogenesis in apolipoprotein E-deficient mice by inhibiting macrophage activation.

    PubMed

    Takashima, Akira; Fukuda, Daiju; Tanaka, Kimie; Higashikuni, Yasutomi; Hirata, Yoichiro; Nishimoto, Sachiko; Yagi, Shusuke; Yamada, Hirotsugu; Soeki, Takeshi; Wakatsuki, Tetsuzo; Taketani, Yutaka; Shimabukuro, Michio; Sata, Masataka

    2016-11-01

    Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are major components of n-3 polyunsaturated fatty acids (n-3 PUFAs) which inhibit atherogenesis, although few studies have examined the effects of the combination of EPA and DHA on atherogenesis. The aim of this study was to investigate whether DHA has additional anti-atherosclerotic effects when combined with EPA. Male 8-week-old apolipoprotein E-deficient (Apoe(-/-)) mice were fed a western-type diet supplemented with different amounts of EPA and DHA; EPA (2.5%, w/w), low-dose EPA + DHA (2.5%, w/w), or high-dose EPA + DHA (5%, w/w) for 20 weeks. The control group was fed a western-type diet containing no n-3 PUFA. Histological and gene expression analysis were performed in atherosclerotic lesions in the aorta. To address the mechanisms, RAW264.7 cells were used. All n-3 PUFA treatments significantly attenuated the development and destabilization of atherosclerotic plaques compared with the control. The anti-atherosclerotic effects were enhanced in the high-dose EPA + DHA group (p < 0.001), whereas the pure EPA group and low-dose EPA + DHA group showed similar results. EPA and DHA additively attenuated the expression of inflammatory molecules in RAW264.7 cells stimulated with LPS. DHA or EPA + DHA suppressed LPS-induced toll-like receptor 4 (TLR4) expression in lipid rafts on RAW264.7 cells (p < 0.05). Lipid raft disruption by methyl-β-cyclodextrin suppressed mRNA expression of inflammatory molecules in LPS-stimulated macrophages. n-3 PUFAs suppressed atherogenesis. DHA combined with EPA had additional anti-inflammatory effects and inhibited atherogenesis in Apoe(-/-) mice. The reduction of TLR4 expression in lipid rafts in macrophages by DHA might be involved in this mechanism, at least partially. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  19. Brief Communication: Plasma lipid oxidation predicts atherosclerotic status better than cholesterol in diabetic apolipoprotein E deficient mice.

    PubMed

    Petersen, Karen Ekkelund; Lykkesfeldt, Jens; Raun, Kirsten; Rakipovski, Günaj

    2017-01-01

    Increased levels of oxidative stress have been suggested to play a detrimental role in the development of diabetes-related vascular complications. Here, we investigated whether the concentration of malondialdehyde, a marker of lipid oxidation correlated to the degree of aortic plaque lesions in a proatherogenic diabetic mouse model. Three groups of apolipoprotein E knockout mice were studied for 20 weeks, a control, a streptozotocin-induced diabetic, and a diabetic enalapril-treated group. Enalapril was hypothesized to lower oxidative stress level and thus the plaque burden. Both diabetic groups were significantly different from the control group as they had higher blood glucose, HbA1c, total cholesterol, low-density lipoprotein, very low-density lipoprotein, together with a lower high-density lipoprotein concentration and body weight. Animals in the diabetic group had significantly higher plaque area and plasma malondialdehyde than controls. The two diabetic groups did not differ significantly in any measured characteristic. In summary, there was a positive correlation between plasma malondialdehyde concentration and aorta plaque area in apolipoprotein E knockout. Even though further investigation of the role of lipid oxidation in the development of atherosclerosis is warranted, these results suggest that biomarkers of lipid oxidation may be of value in the evaluation of cardiovascular risk.

  20. Lack of Toll-like receptor 4 or myeloid differentiation factor 88 reduces atherosclerosis and alters plaque phenotype in mice deficient in apolipoprotein E.

    PubMed

    Michelsen, Kathrin S; Wong, Michelle H; Shah, Prediman K; Zhang, Wenxuan; Yano, Juliana; Doherty, Terence M; Akira, Shizuo; Rajavashisth, Tripathi B; Arditi, Moshe

    2004-07-20

    Toll-like receptors (TLRs) and the downstream adaptor molecule myeloid differentiation factor 88 (MyD88) play an essential role in the innate immune responses. Here, we demonstrate that genetic deficiency of TLR4 or MyD88 is associated with a significant reduction of aortic plaque areas in atherosclerosis-prone apolipoprotein E-deficient mice, despite persistent hypercholesterolemia, implying an important role for the innate immune system in atherogenesis. Apolipoprotein E-deficient mice that also lacked TLR4 or MyD88 demonstrated reduced aortic atherosclerosis that was associated with reductions in circulating levels of proinflammatory cytokines IL-12 or monocyte chemoattractant protein 1, plaque lipid content, numbers of macrophage, and cyclooxygenase 2 immunoreactivity in their plaques. Endothelial-leukocyte adhesion in response to minimally modified low-density lipoprotein was reduced in aortic endothelial cells derived from MyD88-deficient mice. Taken together, our results suggest an important role for TLR4 and MyD88 signaling in atherosclerosis in a hypercholesterolemic mouse model, providing a pathophysiologic link between innate immunity, inflammation, and atherogenesis.

  1. Dietary cholesterol and its effect on tau protein: a study in apolipoprotein E-deficient and P301L human tau mice.

    PubMed

    Glöckner, Frauke; Meske, Volker; Lütjohann, Dieter; Ohm, Thomas G

    2011-04-01

    Apolipoprotein E (ApoE) is the major cholesterol transporter in the brain. There is epidemiological and experimental evidence for involvement of cholesterol metabolism in the development and progression of Alzheimer disease. A dietary effect on tau phosphorylation or aggregation, or a role of apoE in tau metabolism, has been studied experimentally, but the data are ambiguous. To elucidate the relationship between cholesterol and tau, we studied mice expressing P301L mutant human tau but not apoE (htau-ApoE) and P301L mice with wild-type ApoE (htau- ApoE); both genotypes develop neuron cytoskeletal changes similar to those found in Alzheimer disease. Mice were kept on a cholesterol-enriched diet or control diet for 15 weeks. The numbers of neurons with hyperphosphorylated and conformationally changed tau in the cerebral cortex were assessed by immunohistochemistry, and sterol levels were determined. Highly elevated dietary serum cholesterol levels enhanced ongoing tau pathology in htau-ApoE mice; this effect correlated with elevated brain cholesterol metabolite 27-hydroxycholesterol levels. Apolipoprotein E deficiency promoted significant increases of tau phosphorylation and conformational changes in mice on a control diet. In htau-ApoE mice on the high cholesterol regimen, brain oxysterol levels were less than in htau-ApoE mice, and the numbers of neurons with pathologically altered tau were similar to those in htau-ApoE mice on the high-cholesterol diet.

  2. Deficiency of cyclin-dependent kinase inhibitors p21{sup Cip1} and p27{sup Kip1} accelerates atherogenesis in apolipoprotein E-deficient mice

    SciTech Connect

    Akyuerek, Levent M.; Boehm, Manfred; Olive, Michelle; Zhou, Alex-Xianghua; San, Hong; Nabel, Elizabeth G.

    2010-05-28

    Cyclin-dependent kinase inhibitors, p21{sup Cip1} and p27{sup Kip1}, are upregulated during vascular cell proliferation and negatively regulate growth of vascular cells. We hypothesized that absence of either p21{sup Cip1} or p27{sup Kip1} in apolipoprotein E (apoE)-deficiency may increase atherosclerotic plaque formation. Compared to apoE{sup -/-} aortae, both apoE{sup -/-}/p21{sup -/-} and apoE{sup -/-}/p27{sup -/-} aortae exhibited significantly more atherosclerotic plaque following a high-cholesterol regimen. This increase was particularly observed in the abdominal aortic regions. Deficiency of p27{sup Kip1} accelerated plaque formation significantly more than p21{sup -/-} in apoE{sup -/-} mice. This increased plaque formation was in parallel with increased intima/media area ratios. Deficiency of p21{sup Cip1} and p27{sup Kip1} accelerates atherogenesis in apoE{sup -/-} mice. These findings have significant implications for our understanding of the molecular basis of atherosclerosis associated with excessive proliferation of vascular cells.

  3. Cigarette smoke enhances abdominal aortic aneurysm formation in angiotensin II-treated apolipoprotein E-deficient mice.

    PubMed

    Stolle, Katrin; Berges, An; Lietz, Michael; Lebrun, Stefan; Wallerath, Thomas

    2010-12-15

    Cigarette smoke, hyperlipidemia, and hypertension with the risk of development and progression of atherosclerosis and associated pathologies such as abdominal aortic aneurysm (AAA) are correlated. We examined the interaction of cigarette mainstream smoke (MS) and angiotensin-II (Ang II)-induced hypertension in the atherosclerotic process using hyperlipidemic apolipoprotein E-knockout (ApoE(-/-)) mice. ApoE(-/-) mice were treated with Ang II for 4 weeks and then further exposed to MS or to fresh air for 4 weeks. AAA formation was observed in all mice treated with Ang II, regardless of smoke exposure; however, smoke exposure increased the incidence of AAA in these mice. Ang II treatment resulted in higher gene expression of matrix metalloproteinases (MMP)-2, -3, -8, -9, and -12 in the abdominal aortas, which was further increased by MS exposure. The proteolytic activity of MMP-2 and MMP-9 was also enhanced in Ang II-treated mice exposed to MS, but only minor changes were seen with either smoke exposure or Ang II treatment alone. This study shows for the first time that both formation and severity of AAA in hypertensive ApoE(-/-) mice are accelerated by exposure to MS and that the proteolytic activity of MMPs is enhanced by the combination of Ang II and MS. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  4. Reduced alpha-lipoic acid synthase gene expression exacerbates atherosclerosis in diabetic apolipoprotein E-deficient mice.

    PubMed

    Yi, Xianwen; Xu, Longquan; Hiller, Sylvia; Kim, Hyung-Suk; Maeda, Nobuyo

    2012-07-01

    To study the effects of reduced lipoic acid gene expression on diabetic atherosclerosis in apolipoprotein E null mice (Apoe(-/-)). Heterozygous lipoic acid synthase gene knockout mice (Lias(+/-)) crossed with Apoe(-/-) mice were used to evaluate the diabetic effect induced by streptozotocin on atherosclerosis in the aortic sinus of the heart. While diabetes markedly increased atherosclerotic plaque size in Apoe(-/-) mice, a small but significant effect of reduced expression of lipoic acid gene was observed in diabetic Lias(+/-)Apoe(-/-) mice. In the aortic lesion area, the Lias(+/-)Apoe(-/-) mice exhibited significantly increased macrophage accumulation and cellular apoptosis than diabetic Lias(+/+)Apoe(-/-) littermates. Plasma glucose, cholesterol, and interleukin-6 were also higher. These abnormalities were accompanied with increased oxidative stress including a decreased ratio of reduced glutathione/oxidized glutathione in erythrocytes, increased systemic lipid peroxidation, and increased Gpx1 and MCP1 gene expression in the aorta. Decreased endogenous lipoic acid gene expression plays a role in development of diabetic atherosclerosis. These findings extend our understanding of the role of antioxidant in diabetic atherosclerosis. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  5. Influence of environmental enrichment and depleted uranium on behaviour, cholesterol and acetylcholine in apolipoprotein E-deficient mice.

    PubMed

    Lestaevel, P; Airault, F; Racine, R; Bensoussan, H; Dhieux, B; Delissen, O; Manens, L; Aigueperse, J; Voisin, P; Souidi, M

    2014-07-01

    Alzheimer's disease is associated with genetic risk factors, of which the apolipoprotein E (ApoE) is the most prevalent, and is affected by environmental factors that include education early in life and exposure to metals. The industrial and military use of depleted uranium (DU) resulted in an increase of its deposition in some areas and led to a possible environmental factor. The present study aims to ascertain the effects on the behaviour and the metabolism of cholesterol and acetylcholine of ApoE-/- mice exposed to enriched environment (EE) and exposed to DU (20 mg/L) for 14 weeks. Here we show that ApoE-/- mice were unaffected by the EE and their learning and memory were similar to those of the non-enriched ApoE-/- mice. ApoE-/- mice showed a significant decrease in total (-16 %) and free (-16 %) cholesterol in the entorhinal cortex in comparison to control wild-type mice. Whatever the housing conditions, the exposure to DU of ApoE-/- mice impaired working memory, but had no effect on anxiety-like behaviour, in comparison to control ApoE-/- mice. The exposure of ApoE-/- mice to DU also induced a trend toward higher total cholesterol content in the cerebral cortex (+15 %) compared to control ApoE-/- mice. In conclusion, these results demonstrate that enriched environment does not ameliorate neurobehaviour in ApoE-/- mice and that ApoE mutation induced specific effects on the brain cholesterol. These findings also suggested that DU exposure could modify the pathology in this ApoE model, with no influence of housing conditions.

  6. Polychlorinated Biphenyl 77 Augments Angiotensin II-Induced Atherosclerosis and Abdominal Aortic Aneurysms in Male Apolipoprotein E Deficient Mice

    PubMed Central

    Arsenescu, Violeta; Arsenescu, Razvan; Parulkar, Madhura; Karounos, Michael; Zhang, Xuan; Cassis, Lisa A.

    2011-01-01

    Infusion of angiotensin II (AngII) to hyperlipidemic mice augments atherosclerosis and causes formation of abdominal aortic aneurysms (AAAs). Each of these AngII-induced vascular pathologies exhibit pronounced inflammation. Previous studies demonstrated that coplanar polychlorinated biphenyls (PCBs) promote inflammation in endothelial cells and adipocytes, two cell types implicated in AngII-induced vascular pathologies. The purpose of this study was to test the hypothesis that administration of PCB77 to male apolipoprotein E (ApoE) -/- mice promotes AngII-induced atherosclerosis and AAA formation. Male ApoE-/- mice were administered vehicle or PCB77 (49 mg/kg, i.p.) during week 1 and 4 (2 divided doses/week) of AngII infusion. Body weights and total serum cholesterol concentrations were not influenced by administration of PCB77. Systolic blood pressure was increased in AngII-infused mice administered PCB77 compared to vehicle (156 ± 6 vs 137 ± 5 mmHg, respectively). The percentage of aortic arch covered by atherosclerotic lesions was increased in AngII-infused mice administered PCB77 compared to vehicle (2.0 ± 0.4 vs 0.9 ± 0.1 %, respectively). Lumen diameters of abdominal aortas determined by in vivo ultrasound and external diameters of excised suprarenal aortas were increased in AngII-infused mice administered PCB77 compared to vehicle. In addition, AAA incidence increased from 47 to 85% in AngII-infused mice administered PCB77. Adipose tissue in close proximity to AAAs from mice administered PCB77 exhibited increased mRNA abundance of proinflammatory cytokines and elevated expression of components of the renin-angiotensin system (angiotensinogen, angiotensin type 1a receptor (AT1aR)). These results demonstrate that PCB77 augments AngII-induced atherosclerosis and AAA formation. PMID:21925196

  7. Rice α-globulin decreases serum cholesterol concentrations in rats fed a hypercholesterolemic diet and ameliorates atherosclerotic lesions in apolipoprotein E-deficient mice.

    PubMed

    Tong, Li-Tao; Fujimoto, Yumiko; Shimizu, Naoki; Tsukino, Mariko; Akasaka, Taiki; Kato, Yukiko; Iwamoto, Wakako; Shiratake, Sawako; Imaizumi, Katsumi; Sato, Masao

    2012-05-01

    The hypocholesterolemic and antiatherogenic effects of rice α-globulin remain unclear. We investigated the hypocholesterolemic effect of rice α-globulin in rats fed a hypercholesterolemic diet. The rats were divided into 4 groups and were orally administrated the following three proteins or a vehicle for 4weeks: rice protein, rice α-globulin, or soy β-conglycinin at a dose of 100mg/kg body weight or carboxymethylcellulose to the control rats. In the rice α-globulin group, serum cholesterol concentrations were 28% lower than the control group and fecal neutral steroid excretion was increased by 30%. The hypocholesterolemic effect of rice α-globulin was equal to soy β-conglycinin in SD rats fed the hypercholesterolemic diet. However, the serum cholesterol concentrations in the rice protein group did not change compared to the control group. To investigate the antiatherogenic effects of rice α-globulin, male apolipoprotein E-deficient mice were orally administered the same dose of rice α-globulin for 9weeks. The en face lesion area in the aorta was 46% lower than in the control group. In conclusion, administration of rice α-globulin improves hypercholesterolemia in rats fed a hypercholesterolemic diet by increasing the fecal excretion of neutral sterols, and inhibits atherosclerosis development in apolipoprotein E-deficient mice. The anti-atherosclerotic effect exerts by mechanism(s) other than the regulation of serum MCP-1 and NO concentrations.

  8. Polychlorinated biphenyl 77 augments angiotensin II-induced atherosclerosis and abdominal aortic aneurysms in male apolipoprotein E deficient mice

    SciTech Connect

    Arsenescu, Violeta; Arsenescu, Razvan; Parulkar, Madhura; Karounos, Michael; Zhang, Xuan; Baker, Nicki; Cassis, Lisa A.

    2011-11-15

    Infusion of angiotensin II (AngII) to hyperlipidemic mice augments atherosclerosis and causes formation of abdominal aortic aneurysms (AAAs). Each of these AngII-induced vascular pathologies exhibit pronounced inflammation. Previous studies demonstrated that coplanar polychlorinated biphenyls (PCBs) promote inflammation in endothelial cells and adipocytes, two cell types implicated in AngII-induced vascular pathologies. The purpose of this study was to test the hypothesis that administration of PCB77 to male apolipoprotein E (ApoE) -/- mice promotes AngII-induced atherosclerosis and AAA formation. Male ApoE-/- mice were administered vehicle or PCB77 (49 mg/kg, i.p.) during week 1 and 4 (2 divided doses/week) of AngII infusion. Body weights and total serum cholesterol concentrations were not influenced by administration of PCB77. Systolic blood pressure was increased in AngII-infused mice administered PCB77 compared to vehicle (156 {+-} 6 vs 137 {+-} 5 mmHg, respectively). The percentage of aortic arch covered by atherosclerotic lesions was increased in AngII-infused mice administered PCB77 compared to vehicle (2.0 {+-} 0.4 vs 0.9 {+-} 0.1%, respectively). Lumen diameters of abdominal aortas determined by in vivo ultrasound and external diameters of excised suprarenal aortas were increased in AngII-infused mice administered PCB77 compared to vehicle. In addition, AAA incidence increased from 47 to 85% in AngII-infused mice administered PCB77. Adipose tissue in close proximity to AAAs from mice administered PCB77 exhibited increased mRNA abundance of proinflammatory cytokines and elevated expression of components of the renin-angiotensin system (angiotensinogen, angiotensin type 1a receptor (AT1aR)). These results demonstrate that PCB77 augments AngII-induced atherosclerosis and AAA formation. -- Highlights: Black-Right-Pointing-Pointer Polychlorinated biphenyl 77 (PCB77) promotes AngII-induced hypertension. Black-Right-Pointing-Pointer PCB77 augments Ang

  9. Exploring the effects of the atherosclerosis progression and the choice of affected arteries in the design of experiments with Apolipoprotein E-deficient mice.

    PubMed

    Riera-Borrull, Marta; Sabench, Fàtima; del Castillo, Daniel; Camps, Jordi; Joven, Jorge

    2016-01-01

    The objective of this study is to explore the longitudinal progression of atherosclerosis and the correlation between methods to measure the lesion in apolipoprotein E-deficient mice. Atherosclerosis progression was assessed by measurements of foam cell-rich depositions in their proximal aortas, and/or in surgically excised arteries, to assess the histological luminal narrowing. A longitudinal study was performed by comparing the values for carotid, aorta, and femoral and iliac arteries using common histological techniques. There were no significant differences in progression between different arteries, but correlation with the classical measurement of atherosclerosis in the aortic root was poor. Each laboratory requires specific standardization. Carotid arteries were sensitive to atherosclerosis in these mice, and progression was exponential. In conclusion, morphometric data show the importance of the choice of the duration of treatment, the appropriate controls, and the age at which to begin the experiments.

  10. Inhibition of extracellular cyclophilins with cyclosporine analog and development of atherosclerosis in apolipoprotein E-deficient mice.

    PubMed

    Ditiatkovski, Michael; Neelisetti, Vijaya N L V; Cui, Huanhuan L; Malesevic, Miroslav; Fischer, Gunter; Bukrinsky, Michael; Sviridov, Dmitri

    2015-06-01

    Cyclophilins exert both intracellular and extracellular activities related to immune responses and inflammation, which have been implicated in pathogenesis of atherosclerosis. Pan-inhibition of cyclophilins has both pro- and antiatherosclerotic properties, but specific contributions of extracellular and intracellular cyclophilins to these effects have not been characterized. Here, using selective inhibitor of extracellular cyclophilins, we investigated the role of these molecules in atherosclerosis. Apolipoprotein E-null mice fed a high-fat diet received intraperitoneal injections every second day of either vehicle or two analogs of cyclosporine A (CsA): [Melle](4)-CsA (NIM811), a nonimmunosupressive cell-permeable inhibitor of both intracellular and extracellular cyclophilins; and [(4R)-4-[(6-carboxy-1H-benzo[d]imidazol-2-yl)-methyl]-4-methyl-l-threonine](1)-CsA (MM284), cell-impermeable analog only inhibiting extracellular cyclophilins. Development of atherosclerosis and composition of plaques in aorta and innominate artery were studied. Both analogs increased abundance and cross-sectional size of the atherosclerotic plaques in aorta but did not affect development of atherosclerosis in innominate artery. Neither compound affected abundance of macrophages and amount of vascular cell adhesion molecule-1 or nitrotyrosine in the plaques of both arteries. Both compounds reduced the amount of collagen in innominate artery without affecting abundance of collagen in aortic sinus. MM284, but not NIM811, significantly reduced plasma concentration of tumor necrosis factor-α (TNFα); neither compound affected plasma concentrations of interleukin (IL)-6, IL-10 or monocyte chemoattractant protein-1. Ratio between different populations of immune cells in blood or isolated from lymph nodes and spleen as well as plasma lipoprotein profile were unaffected by both compounds. In conclusion, selective inhibition of extracellular cyclophilins reduced TNFα levels in plasma but

  11. Tanshinone II A stabilizes vulnerable plaques by suppressing RAGE signaling and NF-κB activation in apolipoprotein-E-deficient mice

    PubMed Central

    Zhao, Dong; Tong, Lufang; Zhang, Lixin; Li, Hong; Wan, Yingxin; Zhang, Tiezhong

    2016-01-01

    Tanshinone II A (TSIIA) is a diterpene quinone extracted from the roots of Salvia miltiorrhiza with anti-inflammatory and anti-oxidant properties that is used to treat atherosclerosis. In the current study, morphological analyses were conducted to evaluate the effects of TSIIA on atherosclerotic vulnerable plaque stability. Additionally, receptor of advanced glycation end products (RAGE), adhesion molecule, and matrix-metalloproteinases (MMPs) expression, and nuclear factor-κB (NF-κB) activation were examined in apolipoprotein E (apoE)-deficient mice treated with TSIIA. Eight-week-old apoE−/− mice were administered TSIIA and fed an atherogenic diet for 8 weeks. TSIIA exhibited no effects on plaque size. Analysis of the vulnerable plaque composition demonstrated decreased numbers of macrophages and smooth muscle cells, and increased collagen content in apoE-deficient mice treated with TSIIA compared with untreated mice. Western blotting revealed that TSIIA downregulated the expression levels of vascular cellular adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and MMP-2, −3, and −9, suppressed RAGE, and inhibited NF-κB, JNK and p38 activation. The present study demonstrated that the underlying mechanism of TSIIA stabilization of vulnerable plaques involves interfering with RAGE and NF-κB activation, and downregulation of downstream inflammatory factors, including ICAM-1, VCAM-1, and MMP-2, −3 and −9 in apoE−/− mice. PMID:27840935

  12. Matrix metalloproteinase-9 modulation by resident arterial cells is responsible for injury-induced accelerated atherosclerotic plaque development in apolipoprotein E-deficient mice.

    PubMed

    Choi, Eric T; Collins, Emily T; Marine, Leopoldo A; Uberti, Maria G; Uchida, Hisashi; Leidenfrost, Jeremy E; Khan, M Faisal; Boc, Kenneth P; Abendschein, Dana R; Parks, William C

    2005-05-01

    Although matrix metalloproteinase-9 (MMP-9) has been implicated in atherosclerotic plaque instability, the exact role it plays in the plaque development and progression remains largely unknown. We generated apolipoprotein E (apoE)-deficient (apoE-/-) MMP-9-deficient (MMP-9-/-) mice to determine the mechanisms and the main cell source of MMP-9 responsible for the plaque composition during accelerated atherosclerotic plaque formation. Three weeks after temporary carotid artery ligation revealed that while on a Western-type diet, apoE-/- MMP-9-/- mice had a significant reduction in intimal plaque length and volume compared with apoE-/- MMP-9+/+ mice. The reduction in plaque volume correlated with a significantly lower number of intraplaque cells of resident cells and bone marrow-derived cells. To determine the cellular origin of MMP-9 in plaque development, bone marrow transplantation after total-body irradiation was performed with apoE-/- MMP-9+/+ and apoE-/- MMP-9-/- mice, which showed that only MMP-9 derived from resident arterial cells is required for plaque development. MMP-9 is derived from resident arterial cells and is required for early atherosclerotic plaque development and cellular accumulation in apoE-/- mice.

  13. Hyperglycemia Induced by Glucokinase Deficiency Accelerates Atherosclerosis Development and Impairs Lesion Regression in Combined Heterozygous Glucokinase and the Apolipoprotein E-Knockout Mice

    PubMed Central

    Adingupu, Damilola D.; Andréasson, Anne-Christine; Ahnmark, Andrea

    2016-01-01

    Aim. Models combining diabetes and atherosclerosis are important in evaluating the cardiovascular (CV) effects and safety of antidiabetes drugs in the development of treatments targeting CV complications. Our aim was to evaluate if crossing the heterozygous glucokinase knockout mouse (GK+/−) and hyperlipidemic mouse deficient in apolipoprotein E (ApoE−/−) will generate a disease model exhibiting a diabetic and macrovascular phenotype. Methods. The effects of defective glucokinase on the glucose metabolism and on the progression and regression of atherosclerosis on high-fat diets were studied in both genders of GK+/−ApoE−/− and ApoE−/− mice. Coronary vascular function of the female GK+/−ApoE−/− and ApoE−/− mice was also investigated. Results. GK+/−ApoE−/− mice show a stable hyperglycemia which was increased on Western diet. In oral glucose tolerance test, GK+/−ApoE−/− mice showed significant glucose intolerance and impaired glucose-stimulated insulin secretion. Plasma lipids were comparable with ApoE−/− mice; nevertheless the GK+/−ApoE−/− mice showed slightly increased atherosclerosis development. Conclusions. The GK+/−ApoE−/− mice showed a stable and reproducible hyperglycemia, accelerated atherosclerotic lesion progression, and no lesion regression after lipid lowering. This novel model provides a promising tool for drug discovery, enabling the evaluation of compound effects against both diabetic and cardiovascular endpoints simultaneously in one animal model. PMID:27774459

  14. Restraint stress up-regulates lectin-like oxidized low-density lipoprotein receptor-1 in aorta of apolipoprotein E-deficient mice.

    PubMed

    Andersson, Irene J; Sankaralingam, Sowndramalingam; Davidge, Sandra T

    2010-09-01

    Psychological stress is a risk factor for cardiovascular disease including atherosclerosis, but the mechanisms are unknown. The vascular lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is involved in vascular pathology and early atherogenesis. We hypothesized that LOX-1 is up-regulated by psychological stress via the formation of oxygen-derived free radicals, and that treatment with EUK-8 (a superoxide dismutase and catalase mimetic) prevents production of oxygen-derived free radicals and leads to reduced expression of LOX-1 in the vascular wall. As a model for psychological stress, we exposed male apolipoprotein E-deficient mice to repeated restraint stress by placement in a conical tube for 2 h per day for 14 consecutive days. Stressed and control mice were treated with EUK-8 (n = 4-5) or vehicle (n = 4-5). Reactive oxygen species and peroxynitrite levels, as detected by oxidative fluorescence microscopy, were increased in the aortic root of mice exposed to stress compared to those of controls by 212 +/- 22% (mean +/- SEM; p < 0.001) and 110 +/- 6% (p < 0.001), respectively. LOX-1, as detected by immunohistochemistry, was increased by 443 +/- 63% in stressed mice compared to control mice (p < 0.001). EUK-8 reduced reactive oxygen species, peroxynitrite, and LOX-1 levels in stressed mice compared to vehicle-treated stressed mice. To conclude, LOX-1 induced by reactive oxygen species and/or peroxynitrite could be one mechanism by which stress promotes cardiovascular disease.

  15. Protonated nanostructured aluminosilicate (NSAS) reduces plasma cholesterol concentrations and atherosclerotic lesions in Apolipoprotein E deficient mice fed a high cholesterol and high fat diet

    PubMed Central

    Sivak, Olena; Darlington, Jerry; Gershkovich, Pavel; Constantinides, Panayiotis P; Wasan, Kishor M

    2009-01-01

    The aim of this work was to assess the effect of chronic administration of protonated nanostructured aluminosilicate (NSAS) on the plasma cholesterol levels and development of atherosclerotic lesions in Apolipoprotein (ApoE) deficient mice fed a high cholesterol and high fat diet. Apolipoprotein E (ApoE) deficient mice were divided into the following treatment groups: protonated NSAS 1.4% (w/w), untreated control and 2% (w/w) stigmastanol mixed with high-cholesterol/high-fat diet. Animals were treated for 12 weeks, blood samples were withdrawn every 4 weeks for determination of plasma cholesterol and triglyceride levels. At the end of the study the aortic roots were harvested for assessment of atherosclerotic lesions. NSAS at 1.4% (w/w) and stigmastanol at 2% (w/w) treatment groups showed significant decreases in plasma cholesterol concentrations at all time points relative to the control animals. The lesion sum area in 1.4% (w/w) NSAS and 2% (w/w) stigmastanol groups were significantly less from the control animals. In conclusion, in this study, the effectiveness of chronic administration of protonated NSAS material in the reduction of plasma cholesterol levels and decrease in development of atherosclerotic lesions was demonstrated in Apo-E deficient mice model. PMID:19638223

  16. Resveratrol protects against diet-induced atherosclerosis by reducing low-density lipoprotein cholesterol and inhibiting inflammation in apolipoprotein E-deficient mice

    PubMed Central

    Chang, Geng-Ruei; Chen, Po-Lin; Hou, Po-Hsun; Mao, Frank Chiahung

    2015-01-01

    Objective(s): Resveratrol (RES) is a polyphenol compound that has been shown a promising cardioprotective effect. However, some reports have yielded conflicting findings. Herein, we investigated the anti-atherosclerotic effects of RES in apolipoprotein E (apo E)-deficient mice on a high cholesterol diet. Materials and Methods: Firstly, atherosclerosis was induced by feeding a high cholesterol diet to apo E-deficient mice. Then, we examined its effects on weight control, and serum interleukin-6 (IL-6) levels and used histopathological methods to analyze morphology and inflammatory marker of atherosclerotic lesions in mice orally supplemented with high (25 mg/kg/day) and low (5 mg/kg/day) doses of RES for 8 weeks. Results: Mice with high dose of RES had reduced epididymal fat pads, and lower serum IL-6 levels compared with those of control mice. Moreover, RES in high doses also decreased the low-density lipoprotein cholesterol (LDL-C) levels and atherogenic index (LDL-C/HDL-C) in the mice. Dissection of high-dose RES-treated mice revealed a marked reduction in fat deposition, percentage of mice with atherosclerotic lesion, and intima/media ratio in the aortic areas. The expressions of macrophage-specific marker F4/80 and cardiovascular inflammatory marker NF-κB in atherosclerotic vessels were both diminished in the atherosclerotic vessels of high-dose RES-supplementated apo E-deficient mice. Conclusion: These results suggest that RES prevented the effects of a high cholesterol diet on the rate of accretion in atherosclerosis progression by reducing the LDL-C levels and suppressing atherosclerotic inflammation. RES can therefore be valuable in the development of new anti-atherosclerotic agents. PMID:26949492

  17. Lecithin:cholesterol acyltransferase deficiency increases atherosclerosis in the low density lipoprotein receptor and apolipoprotein E knockout mice.

    PubMed

    Furbee, James W; Sawyer, Janet K; Parks, John S

    2002-02-01

    The purpose of the present study was to test the hypothesis that lecithin:cholesterol acyltransferase (LCAT) deficiency would accelerate atherosclerosis development in low density lipoprotein (LDL) receptor (LDLr-/-) and apoE (apoE-/-) knockout mice. After 16 weeks of atherogenic diet (0.1% cholesterol, 10% calories from palm oil) consumption, LDLr-/- LCAT-/- double knockout mice, compared with LDLr-/- mice, had similar plasma concentrations of free (FC), esterified (EC), and apoB lipoprotein cholesterol, increased plasma concentrations of phospholipid and triglyceride, decreased HDL cholesterol, and 2-fold more aortic FC (142 +/- 28 versus 61 +/- 20 mg/g protein) and EC (102 +/- 27 versus 61+/- 27 mg/g). ApoE-/- LCAT-/- mice fed the atherogenic diet, compared with apoE-/- mice, had higher concentrations of plasma FC, EC, apoB lipoprotein cholesterol, and phospholipid, and significantly more aortic FC (149 +/- 62 versus 109 +/- 33 mg/g) and EC (101 +/- 23 versus 69 +/- 20 mg/g) than did the apoE-/- mice. LCAT deficiency resulted in a 12-fold increase in the ratio of saturated + monounsaturated to polyunsaturated cholesteryl esters in apoB lipoproteins in LDLr-/- mice and a 3-fold increase in the apoE-/- mice compared with their counterparts with active LCAT. We conclude that LCAT deficiency in LDLr-/- and apoE-/- mice fed an atherogenic diet resulted in increased aortic cholesterol deposition, likely due to a reduction in plasma HDL, an increased saturation of cholesteryl esters in apoB lipoproteins and, in the apoE-/- background, an increased plasma concentration of apoB lipoproteins.

  18. Fucoidan alleviates high-fat diet-induced dyslipidemia and atherosclerosis in ApoE(shl) mice deficient in apolipoprotein E expression.

    PubMed

    Yokota, Takashi; Nomura, Koichi; Nagashima, Mikio; Kamimura, Naomi

    2016-06-01

    Fucoidan, a sulfated polysaccharide extracted from brown seaweeds, possesses many biological activities including anti-inflammatory and antioxidant activities. We aimed to investigate the protective effects of fucoidan on dyslipidemia and atherosclerosis in apolipoprotein E-deficient mice (ApoE(shl) mice) and to elucidate its molecular targets in the liver by using a transcriptomic approach. For 12weeks, ApoE(shl) mice were fed a high-fat diet (HFD) supplemented with either 1% or 5% fucoidan. Fucoidan supplementation significantly reduced tissue weight (liver and white adipose tissue), blood lipid, total cholesterol (TC), triglyceride (TG), non-high-density lipoprotein cholesterol (non-HDL-C) and glucose levels in HFD-fed ApoE(shl) mice but increased plasma lipoprotein lipase (LPL) activity and HDL-C levels. Fucoidan also reduced hepatic steatosis levels (liver size, TC and TG levels, and lipid peroxidation) and increased white adipose tissue LPL activity. DNA microarray analysis and quantitative reverse transcription-polymerase chain reaction demonstrated differential expression of genes encoding proteins involved in lipid metabolism, energy homeostasis and insulin sensitivity, by activating Ppara and inactivating Srebf1. Fucoidan supplementation markedly reduced the thickness of the lipid-rich plaque, lipid peroxidation and foaming macrophage accumulation in the aorta in HFD-fed ApoE(shl) mice. Thus, fucoidan supplementation appears to have anti-dyslipidemic and anti-atherosclerotic effects by inducing LPL activity and inhibiting the effects of inflammation and oxidative stress in HFD-fed ApoE(shl) mice.

  19. Effects of Aging and Hypercholesterolemia on Oxidative Stress and DNA Damage in Bone Marrow Mononuclear Cells in Apolipoprotein E-deficient Mice

    PubMed Central

    Tonini, Clarissa L.; Campagnaro, Bianca P.; Louro, Lis P. S.; Pereira, Thiago M. C.; Vasquez, Elisardo C.; Meyrelles, Silvana S.

    2013-01-01

    Recent evidence from apolipoprotein E-deficient (apoE−/−) mice shows that aging and atherosclerosis are closely associated with increased oxidative stress and DNA damage in some cells and tissues. However, bone marrow cells, which are physiologically involved in tissue repair have not yet been investigated. In the present study, we evaluated the influence of aging and hypercholesterolemia on oxidative stress, DNA damage and apoptosis in bone marrow cells from young and aged apoE−/− mice compared with age-matched wild-type C57BL/6 (C57) mice, using the comet assay and flow cytometry. The production of both superoxide and hydrogen peroxide in bone marrow cells was higher in young apoE−/− mice than in age-matched C57 mice, and reactive oxygen species were increased in aged C57 and apoE−/− mice. Similar results were observed when we analyzed the DNA damage and apoptosis. Our data showed that both aging and hypercholesterolemia induce the increased production of oxidative stress and consequently DNA damage and apoptosis in bone marrow cells. This study is the first to demonstrate a functionality decrease of the bone marrow, which is a fundamental extra-arterial source of the cells involved in vascular injury repair. PMID:23385237

  20. Stimulation of α7 nicotinic acetylcholine receptor by AR-R17779 suppresses atherosclerosis and aortic aneurysm formation in apolipoprotein E-deficient mice.

    PubMed

    Hashimoto, Toru; Ichiki, Toshihiro; Watanabe, Aya; Hurt-Camejo, Eva; Michaëlsson, Erik; Ikeda, Jiro; Inoue, Eriko; Matsuura, Hirohide; Tokunou, Tomotake; Kitamoto, Shiro; Sunagawa, Kenji

    2014-01-01

    Atherosclerosis is a chronic inflammatory disease. It has been appreciated that vagus nerve inhibits macrophage activation via α7 nicotinic acetylcholine receptor (nAChR), termed the cholinergic anti-inflammatory pathway. We explored the effects of AR-R17779, a selective α7nAChR agonist, on atherosclerosis and aneurysm formation in apolipoprotein E (ApoE)-deficient mice. ApoE-deficient mice were fed a high-fat diet (HFD) and angiotensin II (Ang II) was infused by osmotic minipumps from 10-week-old for 4weeks. AR-R17779 was given in drinking water ad libitum. Oil red O staining of the aorta showed that combined loading of HFD and Ang II induced marked atherosclerosis compared with control mice fed a normal chow. Treatment with AR-R17779 significantly reduced atherosclerotic plaque area and improved survival of mice. Treatment with AR-R17779 also suppressed abdominal aortic aneurysm formation. Quantitative RT-PCR of the aorta revealed that mRNA expression levels of interleukin-1β, interleukin-6 and NOX2 were significantly decreased in AR-R17779-treated mice compared with Ang II+HFD mice. AR-R17779 treatment also reduced blood pressure and serum lipid levels. In conclusion, α7nAChR activation attenuates atherogenesis and aortic abdominal aneurysm formation in ApoE-deficient mice possibly through an anti-inflammatory effect and reduction of blood pressure and lipid levels. Pharmacological activation of α7nAChR may have a therapeutic potential against atherosclerotic vascular diseases through multiple mechanisms. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. In vivo magnetic resonance imaging of atherosclerotic lesions with a newly developed Evans blue-DTPA-gadolinium contrast medium in apolipoprotein-E-deficient mice.

    PubMed

    Yasuda, Satoshi; Ikuta, Kenjiro; Uwatoku, Toyokazu; Oi, Keiji; Abe, Kohtaro; Hyodo, Fuminori; Yoshimitsu, Kengo; Sugimura, Kohtaro; Utsumi, Hideo; Katayama, Yoshiki; Shimokawa, Hiroaki

    2008-01-01

    Magnetic resonance imaging (MRI) contrast agents that specifically detect atherosclerotic plaque may be useful for the noninvasive detection of the plaque. We have recently developed a new contrast agent, Evans blue-DTPA-gadolinium (EB-DTPA-Gd), which selectively accumulates vascular lesions with endothelial removal. In this study, we examined whether EB-DTPA-Gd is also useful for in vivo imaging of atherosclerotic plaques. We used male apolipoprotein-E-deficient (ApoE-/-) mice of different ages (3, 6 and 12 months old) and age-matched male wild-type mice. After a single intravenous administration of EB-DTPA-Gd (160 microM/kg body weight), MRI T(1) signal was obtained in vivo. Increased signal intensity in the aortic wall was noted within 10-20 min after intravenous injection of EB-DTPA-Gd and was maintained for 30 min. The MRI enhancement in the aorta of ApoE-/- mice was increased in accordance with age, whereas no such enhancement was noted in wild-type mice. Histological examination demonstrated that there was a topological correlation between the site of MRI enhancement and that of atherosclerotic plaque. These results indicate that EB-DTPA-Gd is a useful MRI contrast medium for the in vivo detection of atherosclerotic plaques. Copyright (c) 2007 S. Karger AG, Basel.

  2. Sex as a profound modifier of atherosclerotic lesion development in apolipoprotein E-deficient mice with different genetic backgrounds.

    PubMed

    Surra, Joaquín C; Guillén, Natalía; Arbonés-Mainar, José M; Barranquero, Cristina; Navarro, María A; Arnal, Carmen; Orman, Israel; Segovia, José C; Osada, Jesús

    2010-07-30

    Research suggests that sex may condition atherosclerosis development against different genetic backgrounds. This study addresses the hypothesis that this effect would be exerted by changes in the different apolipoproteins present in high-density lipoproteins. ApoE-deficient mice of both sexes with Ola 129 and C57BL/6J genetic backgrounds were fed a chow diet for 14 weeks. At the end of the dietary intervention, the development of atherosclerotic lesions, apolipoproteins, lipid metabolism, inflammation and paraoxonase were assessed. Differences between atherosclerotic lesions in Ola 129 and C57BL/6J strains of apoE-deficient mice were sex-dependent and were only statistically significant in females. Plasma levels of HDL cholesterol and apolipoproteins related to these lipoparticles, such as apoA-I, apoA-II, apoA-IV, apoA-V and apoJ, were significantly different between these two strains and there were sex-related differences in some of these apolipoproteins. Hepatic steatosis was also related to the strain and was independent of sex. In females, changes in HDL cholesterol and apolipoproteins A-I and A-II were important determinants of atherosclerosis, while this was not the case in males. Our results demonstrate that atherosclerosis-related differences between Ola129 and C57BL/6J genetic backgrounds in apoE-deficient mice are sex-dependent and that this finding is explained by the differences in HDL cholesterol and its apolipoprotein components, mainly apoA-I and A-II. Overall, our findings highlight the importance of taking sex into account in the analysis of atherosclerosis and lipid metabolism in animal models.

  3. Apolipoprotein E-deficient mice created by systemic administration of antisense oligodeoxynucleotides: a new model for lipoprotein metabolism studies.

    PubMed

    Morishita, R; Gibbons, G H; Kaneda, Y; Zhang, L; Ogihara, T; Dzau, V J

    2002-11-01

    Atherosclerotic cardiovascular disease results from complex interactions among multiple genetic and environmental factors. Thus, it is important to elucidate the influence of each factor on cholesterol metabolism. For this purpose, transgenic/gene-targeting technology is a powerful tool for studying gene functions. However, this technology has several disadvantages such as being time consuming and expensive. Accordingly, we established new animal models using in vivo gene transfer technology. In this study, we examined the feasibility of the creation of a new animal model for the study of atherosclerosis. We hypothesized that apolipoprotein (apo) E-deficient mice can be created by systemic administration of antisense apo E oligodeoxynucleotides (ODN) coupled to the HVJ-liposome complex. Initially, we examined the localization and cellular fate of FITC-labeled antisense ODN administered intravenously. FITC-labeled ODN transfection by the HVJ-liposome method resulted in fluorescence in the liver, spleen and kidney, but not in other organs such as brain. Moreover, fluorescence with the HVJ-liposome method was sustained for up to 2 weeks after transfection, which resulted in a striking difference from transfection of ODN alone or ODN in liposomes without HVJ, which showed rapid disappearance of fluorescence (within 1 day). Given these unique characteristics of the HVJ-liposome method, we next examined transfection of antisense apo E ODN by intravenous administration. Transfection of antisense apo E ODN resulted in a marked reduction of apo E mRNA levels in the liver, but no change in apo B and beta-actin mRNA levels. In mice fed a normal diet, a transient increase in cholesterol and triglyceride levels was observed in the antisense apo E-treated group, but they returned to normal levels by 6 days after transfection. Similar findings were also found in mice fed a high cholesterol diet. Neither scrambled nor mismatched ODN resulted in any increase in cholesterol. To make

  4. [Anti-β2GPI antibody promotes release of inflammatory and pro-thrombosis molecules from arteries in apolipoprotein E-deficient mice].

    PubMed

    Zhu, Xiaojie; Zhou, Hong; Wang, Xiaoyan; Cai, Qianqian; He, Chao; Xia, Longfei; Zhang, Guiting; Ouyang, Hang

    2017-03-01

    Objective To investigate the roles of anti-beta 2 glycoprotein I antibodies (anti-β2GPI Ab) in the expressions of atherosclerosis(AS)-related inflammatory factors and pro-thrombosis molecules in apolipoprotein E-deficient (ApoE-/-) mice. Methods ApoE-/- mice were randomly divided into normal saline (NS) group, 100 μg anti-β2GPI Ab group, 100 μg homologous antibody (rabbit-IgG) group and 100 μg β2GPI/anti-β2GPI Ab complex group after silastic collars were placed around their carotid arteries by surgery. All mice were fed a high fat diet and corresponding stimuli were given through intraperitoneal injection at 7-day intervals. Six weeks later, the mice were executed. The blockage of carotid arteries of the operated side was observed by HE staining. The expressions of TLR4, tissue factor (TF) and von Willebrand factor (vWF) were detected by immunohistochemistry. The mRNA levels of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in aorta were tested by real-time quantitative PCR. Results HE staining showed that the blockage of carotid arteries in antibody group was the most obvious. The immunohistochemistry showed that the expressions of TLR4, TF and vWF in anti-β2GPI Ab group increased remarkably. Furthermore, the mRNA levels of IL-1β and TNF-α in anti-β2GPI Ab group were higher than those in the other groups. Conclusion The anti-β2GPI antibody promotes the formation of atherosclerotic plaques in mice by up-regulating the release of inflammatory cytokines IL-1β, TNF-α and thrombosis-related molecules TF, vWF and TLR4, ultimately enhancing the development of AS.

  5. Sesamin attenuates intercellular cell adhesion molecule-1 expression in vitro in TNF-alpha-treated human aortic endothelial cells and in vivo in apolipoprotein-E-deficient mice.

    PubMed

    Wu, Wen-Huey; Wang, Shu-Huei; Kuan, I-I; Kao, Ya-Shi; Wu, Pei-Jhen; Liang, Chan-Jung; Chien, Hsiung-Fei; Kao, Chiu-Hua; Huang, Ching-Jang; Chen, Yuh-Lien

    2010-09-01

    Sesame lignans have antioxidative and anti-inflammatory properties. We focused on the effects of the lignans sesamin and sesamol on the expression of endothelial-leukocyte adhesion molecules in tumor necrosis factor-alpha (TNF-alpha)-treated human aortic endothelial cells (HAECs). When HAECs were pretreated with sesamin (10 or 100 microM), the TNF-alpha-induced expression of intercellular cell adhesion molecule-1 (ICAM-1) was significantly reduced (35 or 70% decrease, respectively) by Western blotting. Sesamol was less effective at inhibiting ICAM-1 expression (30% decrease at 100 microM). Sesamin and sesamol reduced the marked TNF-alpha-induced increase in human antigen R (HuR) translocation and the interaction between HuR and the 3'UTR of ICAM-1 mRNA. Both significantly reduced the binding of monocytes to TNF-alpha-stimulated HAECs. Sesamin significantly attenuated TNF-alpha-induced ICAM-1 expression and cell adhesion by downregulation of extracellular signal-regulated kinase 1/2 and p38. Furthermore, in vivo, sesamin attenuated intimal thickening and ICAM-1 expression seen in aortas of apolipoprotein-E-deficient mice. Taken together, these data suggest that sesamin inhibits TNF-alpha-induced extracellular signal-regulated kinase/p38 phosphorylation, nuclear translocation of NF-kappaB p65, cytoplasmic translocalization of HuR and thereby suppresses ICAM-1 expression, resulting in reduced adhesion of leukocytes. These results also suggest that sesamin may prevent the development of atherosclerosis and inflammatory responses.

  6. Recombinant human erythropoietin suppresses endothelial cell apoptosis and reduces the ratio of Bax to Bcl-2 proteins in the aortas of apolipoprotein E-deficient mice

    PubMed Central

    Warren, Jeffrey S.; Zhao, Ying; Yung, Raymond; Desai, Anjali

    2013-01-01

    Recent clinical trials have raised concern that therapy with recombinant human erythropoietin (EPO) may increase cardiovascular disease risk, event rate, and mortality. Endothelial cell (EC) apoptosis has been implicated in both atherogenesis as well as in the destabilization and rupture of atheromatous plaques. In the current study we observed that EPO and the EPO-mimetic peptide EMP-1 markedly suppressed lipopolysaccharide-induced apoptosis in EC monolayers. Therapeutic concentrations of EPO upregulated Bcl-2 expression while concurrently diminishing expression of Bax, resulting in a net decrease in the ratio of Bax to Bcl-2 protein concentrations. In vivo studies demonstrated that erythropoietin receptor (EPOR) is abundantly expressed in murine aorta and that EPO treatment for 10 weeks markedly decreased the ratio of Bax to Bcl-2 protein in the aortas of apolipoprotein E-deficient (APO E-KO) mice fed a high-fat diet. To our knowledge these data are the first to reveal a modulation of regulators of the apoptotic pathway in murine aorta by chronic EPO treatment. These observations imply that long-term administration of EPO may have the potential to affect plaque stability. PMID:21242808

  7. Cigarette-smoke-induced atherogenic lipid profiles in plasma and vascular tissue of apolipoprotein E-deficient mice are attenuated by smoking cessation.

    PubMed

    Lietz, Michael; Berges, An; Lebrun, Stefan; Meurrens, Kris; Steffen, Yvonne; Stolle, Katrin; Schueller, Jutta; Boue, Stephanie; Vuillaume, Grégory; Vanscheeuwijck, Patrick; Moehring, Michaela; Schlage, Walter; De Leon, Hector; Hoeng, Julia; Peitsch, Manuel

    2013-07-01

    Tobacco smoke exerts perturbations on lipid metabolism and arterial cell function that accelerate atherosclerosis. Lipidomics has emerged as a key technology in helping to elucidate the lipid-related mechanisms of atherosclerosis. In this study, we investigated the effects of smoking cessation on plaque development and aortic arch content of various lipid molecular classes and species. Apolipoprotein E-deficient mice were exposed to fresh air (sham) or to mainstream cigarette smoke (CS) for 6 months, or to CS for 3 months followed by sham for 3 months (cessation group). Lipids from plasma and aortic arches, plasma lipoprotein profiles and plaque morphometry measurements were analyzed. We already showed that CS exposure accelerated plaque size and total cholesterol content of the aortic arch at 3 and 6 months. Marked increases were seen in the relative enrichment of cholesteryl esters, phospholipids, sphingomyelins, and glycosphingolipids. Smoking cessation slowed plaque progression and resulted in lower levels of many lipid species in plasma and aortic arch. While CS exposure promoted rapid lipid accumulation in mouse aorta, smoking cessation translated into a slow removal of lipids from the vessel wall. Despite the smoking cessation-dependent metabolic changes leading to increased animal body weight, accumulation of proatherogenic lipids in the vessel was halted after exposure cessation, indicating that the clinical benefits of smoking cessation translate directly to the vessel wall and its lipid makeup.

  8. Intermedin1–53 Protects Against Myocardial Fibrosis by Inhibiting Endoplasmic Reticulum Stress and Inflammation Induced by Homocysteine in Apolipoprotein E-Deficient Mice

    PubMed Central

    Zhang, Jin-Sheng; Hou, Yue-Long; Lu, Wei-Wei; Ni, Xian-Qiang; Lin, Fan; Yu, Yan-Rong; Tang, Chao-Shu

    2016-01-01

    Aim: Endoplasmic reticulum stress (ERS) and inflammation participate in cardiac fibrosis. Importantly, a novel paracrine/autocrine peptide intermedin1–53 (IMD1–53) in the heart inhibits myocardial fibrosis in rats. However, the mechanisms are yet to be fully elucidated. Methods: Myocardial fibrosis in apolipoprotein E-deficient (ApoE -/-) mice and neonatal rat cardiac fibroblasts (CFs) were induced using homocysteine (Hcy). Results: IMD1–53 inhibited myocardial fibrosis in vivo and in vitro. Picrosirius red staining showed that IMD1–53 reduced myocardial interstitial collagen deposition in ApoE-/- mice treated with Hcy and decreased the expression of myocardial collagen I and III, which was further verified in rat CFs. IMD1–53 attenuated myocardial hypertrophy, as shown by cardiomyocyte cross-sectional area, ratio of heart weight to body weight, and mRNA levels of atrial natriuretic peptide and brain natriuretic peptide. IMD1–53 inhibited the upregulation of ERS hallmarkers such as glucose-regulated protein 78 (GRP78), GRP94, activating transcription factor 6 (ATF6), ATF4, inositol-requiring enzyme 1α, spliced-X-box-binding protein-1, protein kinase receptor-like ER kinase, and eukaryotic translation initiation factor 2α in mouse myocardium and rat CFs treated with Hcy. In addition, IMD1–53 decreased the production of inflammatory factors such as tumor necrosis factor-α, monocyte chemotactic protein-1, interleukin-6 (IL-6), and IL-1β in the mouse myocardium and rat CFs treated with Hcy. Concurrently, IMD1–53 ameliorated the expression of nuclear factor-κB, transforming growth factor-β1, and c-Jun N-terminal kinase in the mouse myocardium and rat CFs treated with Hcy. Conclusions: IMD potentially protects against myocardial fibrosis induced by Hcy in ApoE-/- mice, possibly via attenuating myocardial ERS and inflammation. PMID:27052784

  9. Inhibition of c-Jun N-terminal kinase attenuates low shear stress-induced atherogenesis in apolipoprotein E-deficient mice.

    PubMed

    Wang, Juan; An, Feng Shuang; Zhang, Wei; Gong, Lei; Wei, Shu Jian; Qin, Wei Dong; Wang, Xu Ping; Zhao, Yu Xia; Zhang, Yun; Zhang, Cheng; Zhang, Ming-Xiang

    2011-01-01

    Atherosclerosis begins as local inflammation of arterial walls at sites of disturbed flow, such as vessel curvatures and bifurcations with low shear stress. c-Jun NH₂-terminal kinase (JNK) is a major regulator of flow-dependent gene expression in endothelial cells in atherosclerosis. However, little is known about the in vivo role of JNK in low shear stress in atherosclerosis. We aimed to observe the effect of JNK on low shear stress-induced atherogenesis in apolipoprotein E-deficient (ApoE(-/-)) mice and investigate the potential mechanism in human umbilical vein endothelial cells (HUVECs). We divided 84 male ApoE(-/-) mice into two groups for treatment with normal saline (NS) (n = 42) and JNK inhibitor SP600125 (JNK-I) (n = 42). Perivascular shear stress modifiers were placed around the right carotid arteries, and plaque formation was studied at low shear stress regions. The left carotid arteries without modifiers represented undisturbed shear stress as a control. The NS group showed atherosclerotic lesions in arterial regions with low shear stress, whereas the JNK-I group showed almost no atherosclerotic lesions. Corresponding to the expression of proatherogenic vascular cell adhesion molecule 1 (VCAM-1), phospho-JNK (p-JNK) level was higher in low shear stress regions with NS than with JNK-I inhibitor. In HUVECs under low shear stress, siRNA knockdown and SP600125 inhibition of JNK attenuated nuclear factor (NF)-κB activity and VCAM-1 expression. Furthermore, siRNA knockdown of platelet endothelial cell adhesion molecule 1 (PECAM-1) (CD31) reduced p-JNK and VCAM-1 levels after low shear stress stimulation. JNK may play a critical role in low shear stress-induced atherogenesis by a PECAM-1-dependent mechanosensory pathway and modulating NF-κB activity and VCAM-1 expression.

  10. Dietary intake of cod and scallop reduces atherosclerotic burden in female apolipoprotein E-deficient mice fed a Western-type high fat diet for 13 weeks.

    PubMed

    Jensen, Ida-Johanne; Walquist, Mari; Liaset, Bjørn; Elvevoll, Edel O; Eilertsen, Karl-Erik

    2016-01-01

    It is now increasingly recognized that the beneficial effects of seafood consumption is not limited to lipids and fatty acid, but that the protein part, i.e., peptides and amino acids, together with vitamins and even unknown bioactive constituents also are important for disease prevention. This study was designed to evaluate the putative anti-atherogenic effects of different protein sources (a lean seafood and a nonseafood) in apolipoprotein E-deficient (apoE(-/-)) mice. Twenty-four 5-week-old female apoE(-/-) mice were fed Western type diets containing chicken or a combination of cod and scallops as dietary protein sources for 13 weeks. Atherosclerotic plaque burden, weight, serum levels of leptin, glucose and LDL cholesterol as well as gene expressions from liver and heart were evaluated. Statistical analyses were performed using SPSS. Differences between the variables were evaluated using independent t-test or Mann-Whitney U test for normally and non-normally distributed variables, respectively. Normality was defined by the Shapiro-Wilk test. The mice fed cod-scallop had a 24 % (p < 0.05) reduced total aorta atherosclerotic plaque burden compared to the chicken fed group, whereas the reduction in plaque in the less lesion prone thoracic and abdominal parts of the descending aorta were 46 % (p < 0.05) and 56 % (p < 0.05), respectively. In addition, mice fed cod-scallop gained less weight, and had lower serum levels of leptin, glucose and LDL cholesterol, compared to those fed chicken. Analysis of expression of the genes from liver and heart showed that hepatic endogenous antioxidant paraoxonase 2 (Pon2 gene) and the vascular cell adhesion molecule VCAM-1 (Vcam1 gene) were down regulated in mice fed cod-scallop compared to mice fed chicken. The present study revealed a metabolic beneficial effect of lean seafood compared to chicken, as atherosclerotic plaque burden, serum glucose, leptin and LDL cholesterol levels were reduced in mice fed cod-scallop.

  11. The intravenous injection of oxidized LDL- or Apolipoprotein B100 – Coupled splenocytes promotes Th1 polarization in wildtype and Apolipoprotein EDeficient mice

    SciTech Connect

    Steinmetz, Martin; Ponnuswamy, Padmapriya; Laurans, Ludivine; Esposito, Bruno; Tedgui, Alain; Mallat, Ziad

    2015-08-14

    Background: Th1 responses in atherosclerosis are mainly associated with the aggravation of atherosclerotic plaques, whereas Th2 responses lead to a less pronounced disease in mouse models. The fixation of antigens on cells by means of ethylene carbodiimide (ECDI), and subsequent injection of these antigen-coupled splenocytes (Ag-SP) to induce tolerance against the attached antigens, has been successfully used to treat murine type 1 diabetes or encephalomyelitis in. We analyzed this approach in a mouse model for atherosclerosis. Methods and results: OTII-transgenic mice that were treated with a single dose of 5 × 10{sup 7} OVA-coupled splenocytes (OVA-SP), had decreased splenocyte proliferation, and lower IFNγ production in vitro upon antigen recall. However, in vivo CD4 cell activation was increased. To try lipoprotein-derived, “atherosclerosis-associated” antigens, we first tested human oxidized LDL. In wild type mice, an increase of IFNγ production upon in vitro recall was detected in the oxLDL-SP group. In Apolipoprotein Edeficient (ApoE−/−) mice that received oxLDL-SP every 5 weeks for 20 weeks, we did not find any difference of atherosclerotic plaque burden, but again increased IFNγ production. To overcome xenogenous limitations, we then examined the effects of mouse Apolipoprotein B100 peptides P3 and P6. ApoB100-SP treatment again promoted a more IFNγ pronounced response upon in vitro recall. Flow cytometry analysis of cytokine secreting spleen cells revealed CD4 positive T cells to be mainly the source for IFNγ. In ApoE−/− mice that were administered ApoB100-SP during 20 weeks, the atherosclerotic plaque burden in aortic roots as well as total aorta was unchanged compared to PBS treated controls. Splenocyte proliferation upon antigen recall was not significantly altered in ApoB100-SP treated ApoE−/− mice. Conclusion: Although we did not observe a relevant anti-atherosclerotic benefit, the treatment with antigen

  12. β-Elemene attenuates atherosclerosis in apolipoprotein E-deficient mice via restoring NO levels and alleviating oxidative stress.

    PubMed

    Liu, Meng; Chen, Xiaotong; Ma, Ji; Hassan, Waseem; Wu, Huali; Ling, Jiawei; Shang, Jing

    2017-09-25

    β-Elemene is a major bioactive sesquiterpenoids compound isolated from the essential oils of Curcuma Wenyujin, a Chinese medicinal herb that treats tumor in clinics. However anti-atherosclerotic effects of β-elemene have not been fully investigated in vivo. The objective of this study is to further elucidate the anti-atherosclerotic activities of β-elemene in ApoE(-/-) mice. Staining techniques and immunohistochemistry were used to validate atherosclerosis. Serum lipids, plasma nitrite and nitrate were analyzed by colorometric methods. ROS and antioxidative enzymes were measured through kits. Proteome profiler array was performed to analyze atherosclerosis-related inflammatory Cytokine. Western blot was used for measuring various proteins expressions. These results revealed that β-elemene inhibited atherosclerotic lesion size and increased stability of plaques in ApoE(-/-) mice by alleviating levels of vascular oxidative stress and preventing pro-inflammatory cytokine production. In addition β-elemene maintained endothelial function by significantly improving plasma nitrite and nitrate levels and expression of phosphorylation-eNOS in vivo. β-elemene also increased the production of the nitric oxide (NO) in human umbilical vein endothelial cells (HUVECs) and promoted phosphorylation of eNOS(ser1177) and Akt in vitro. In Conclusive, data revealed that β-elemene attenuated atherosclerosis and enhanced stability of plaques at least partially through its antioxidative and anti-inflammatory features and protected against endothelial dysfunction in ApoE(-/-) mice. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  13. The intravenous injection of oxidized LDL- or Apolipoprotein B100--Coupled splenocytes promotes Th1 polarization in wildtype and Apolipoprotein E--Deficient mice.

    PubMed

    Steinmetz, Martin; Ponnuswamy, Padmapriya; Laurans, Ludivine; Esposito, Bruno; Tedgui, Alain; Mallat, Ziad

    2015-08-14

    Th1 responses in atherosclerosis are mainly associated with the aggravation of atherosclerotic plaques, whereas Th2 responses lead to a less pronounced disease in mouse models. The fixation of antigens on cells by means of ethylene carbodiimide (ECDI), and subsequent injection of these antigen-coupled splenocytes (Ag-SP) to induce tolerance against the attached antigens, has been successfully used to treat murine type 1 diabetes or encephalomyelitis in. We analyzed this approach in a mouse model for atherosclerosis. OTII-transgenic mice that were treated with a single dose of 5 × 10(7) OVA-coupled splenocytes (OVA-SP), had decreased splenocyte proliferation, and lower IFNγ production in vitro upon antigen recall. However, in vivo CD4 cell activation was increased. To try lipoprotein-derived, "atherosclerosis-associated" antigens, we first tested human oxidized LDL. In wild type mice, an increase of IFNγ production upon in vitro recall was detected in the oxLDL-SP group. In Apolipoprotein E - deficient (ApoE-/-) mice that received oxLDL-SP every 5 weeks for 20 weeks, we did not find any difference of atherosclerotic plaque burden, but again increased IFNγ production. To overcome xenogenous limitations, we then examined the effects of mouse Apolipoprotein B100 peptides P3 and P6. ApoB100-SP treatment again promoted a more IFNγ pronounced response upon in vitro recall. Flow cytometry analysis of cytokine secreting spleen cells revealed CD4 positive T cells to be mainly the source for IFNγ. In ApoE-/- mice that were administered ApoB100-SP during 20 weeks, the atherosclerotic plaque burden in aortic roots as well as total aorta was unchanged compared to PBS treated controls. Splenocyte proliferation upon antigen recall was not significantly altered in ApoB100-SP treated ApoE-/- mice. Although we did not observe a relevant anti-atherosclerotic benefit, the treatment with antigen-coupled splenocytes in its present form already impacts the immune responses and

  14. Teneligliptin, a dipeptidyl peptidase-4 inhibitor, attenuated pro-inflammatory phenotype of perivascular adipose tissue and inhibited atherogenesis in normoglycemic apolipoprotein-E-deficient mice.

    PubMed

    Salim, Hotimah Masdan; Fukuda, Daiju; Higashikuni, Yasutomi; Tanaka, Kimie; Hirata, Yoichiro; Yagi, Shusuke; Soeki, Takeshi; Shimabukuro, Michio; Sata, Masataka

    2017-09-01

    Dipeptidyl peptidase-4 (DPP-4) inhibitors have various cellular effects that are associated with vascular protection. Here, we examined whether teneligliptin alters the pro-inflammatory phenotype of perivascular adipose tissue (PVAT) and inhibits atherogenesis. Teneligliptin (60mg/kg/day) was administered orally to apolipoprotein-E-deficient (ApoE(-/-)) mice for 20weeks. Teneligliptin significantly inhibited the development of atherosclerosis in the aortic arch compared with vehicle (P<0.05), without alteration of blood glucose level or blood pressure. Histological analyses demonstrated that teneligliptin decreased lipid deposition and MCP-1 expression (P<0.05, respectively), and tended to decrease macrophage accumulation in atherosclerotic plaques. The results of quantitative RT-PCR analysis demonstrated that teneligliptin reduced the expression of inflammatory molecules such as TNF-α and MCP-1 in the abdominal aorta. Furthermore, teneligliptin reduced the expression of a macrophage marker and Nox-4, a major NADPH oxidase subunit in adipocytes, in PVAT around the aortic arch. Administration of teneligliptin for 8weeks ameliorated endothelium-dependent vasodilation and reduced oxidative stress as determined by urinary 8-OHdG excretion (P<0.05) compared with vehicle. In vitro experiments demonstrated that exendin-4 (Ex-4), a GLP-1 analog, decreased the expression of inflammatory molecules in RAW264.7 cells. Also, Ex-4 decreased Nox4 expression in 3T3-L1 adipocytes. Teneligliptin inhibited atherogenesis with attenuation of the inflammatory phenotype in PVAT. A GLP-1 analog suppressed pro-inflammatory activation of macrophages and adipocytes. Suppression of the pro-inflammatory phenotype of PVAT might contribute, at least partially, to the cardioprotective effects of teneligliptin. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Tauroursodeoxycholic Acid Attenuates Angiotensin II Induced Abdominal Aortic Aneurysm Formation in Apolipoprotein E-deficient Mice by Inhibiting Endoplasmic Reticulum Stress.

    PubMed

    Qin, Y; Wang, Y; Liu, O; Jia, L; Fang, W; Du, J; Wei, Y

    2017-03-01

    Abdominal aortic aneurysm (AAA) is characterised by the infiltration of smooth muscle cell (SMC) apoptosis, inflammatory cells, neovascularisation, and degradation of the extracellular matrix. Previous work has shown that endoplasmic reticulum (ER) stress and SMC apoptosis were increased both in a mouse model and human thoracic aortic aneurysm. However, whether the ER stress is activated in AAA formation and whether suppressing ER stress attenuates AAA is unknown. Human AAA and control aorta samples were collected. Expression of ER stress chaperones glucose-regulated protein (GRP)-78 and GRP-94 was detected by immunohistochemical staining. The effect of ER stress inhibitor tauroursodeoxycholic acid (TUDCA) on AAA formation in angiotensin (Ang) II induced apolipoprotein E(-/-) mice was explored. Elastin staining was used to observe the rupture of elastic fragmentation. Immunohistochemistry and Western blot analysis were performed, to detect the protein expression of ER stress chaperones and apoptosis molecules. There was significant upregulation of GRP-78 and GRP-94 in aneurysmal areas of human AAA and Ang II induced ApoE(-/-) mice (p < .05). TUDCA significantly attenuated the maximum diameters of abdominal aortas in Ang II induced ApoE(-/-) mice (p < .05). TUDCA significantly reduced expression of ER stress chaperones and the apoptotic cell numbers (p < .05). Furthermore, TUDCA significantly reduced expression of apoptosis molecules, such as caspase-3, caspase-12, C/EBP homologous protein, c-Jun N-terminal kinase activating transcription factor 4, X-box binding protein, and eukaryotic initiation factor 2α in Ang II induced ApoE(-/-) mice (p < .05). The results suggest that ER stress is involved in human and Ang II induced AAA formation in ApoE(-/-) mice. TUDCA attenuates Ang II induced AAA formation in ApoE(-/-) mice by inhibiting ER stress mediated apoptosis. Copyright © 2016 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights

  16. A human apolipoprotein E mimetic peptide reduces atherosclerosis in aged apolipoprotein E null mice

    PubMed Central

    Xu, Yanyong; Liu, Hongmei; Liu, Mengting; Li, Feifei; Liu, Liangchen; Du, Fen; Fan, Daping; Yu, Hong

    2016-01-01

    Apolipoprotein E (apoE) is well known as an antiatherogenic protein via regulating lipid metabolism and inflammation. We previously reported that a human apoE mimetic peptide, EpK, reduced atherosclerosis in apoE null (apoE-/-) mice through reducing inflammation without affecting plasma lipid levels. Here, we construct another human apoE mimetic peptide, named hEp, and investigate whether expression of hEp can reduce atherosclerotic lesion development in aged female apoE-/- mice with pre-existing lesions. We found that chemically synthesized hEp significantly decreased cholesterol accumulation induced by oxidized low density lipoprotein and the expression of inflammatory cytokines TNFα and IL-6 induced by lipopolysaccharide in macrophages. In an in vivo study, Lv-hEp-GFP lentiviruses were intravenously injected into 9 month-old apoE-/- mice. Mice were then fed a chow diet for 18 weeks. Results showed that in comparison to the Lv-GFP lentivirus injection (Lv-GFP) group, Lv-hEp-GFP lentivirus injection achieved hepatic hEp expression and secretion in apoE-/- mice. It was observed that hEp expression significantly reduced plasma VLDL and LDL cholesterol levels and decreased aortic atherosclerotic lesions. This was accompanied by an increase of LDL receptor expression and a reduction of TNFα and IL-6 mRNA levels in the liver. Moreover, expression of hEp increased plasma paraoxonase-1 activity and decreased plasma myeloperoxidase activity and serum amyloid A levels. Our study provides evidence that hEp may be developed as a promising therapeutic apoE mimetic peptide for atherosclerosis-related cardiovascular diseases through its induction of plasma VLDL/LDL cholesterol clearance as well as its anti-oxidative and anti-inflammatory activities. PMID:27648138

  17. Compared with saturated fatty acids, dietary monounsaturated fatty acids and carbohydrates increase atherosclerosis and VLDL cholesterol levels in LDL receptor-deficient, but not apolipoprotein E-deficient, mice.

    PubMed

    Merkel, M; Velez-Carrasco, W; Hudgins, L C; Breslow, J L

    2001-11-06

    Heart-healthy dietary recommendations include decreasing the intake of saturated fatty acids (SFA). However, the relative benefit of replacing SFA with monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), or carbohydrates (CARB) is still being debated. We have used two mouse models of atherosclerosis, low density lipoprotein receptor-deficient (LDLRKO) and apolipoprotein E-deficient (apoEKO) mice to measure the effects of four isocaloric diets enriched with either SFA, MUFA, PUFA, or CARB on atherosclerotic lesion area and lipoprotein levels. In LDLRKO mice, compared with the SFA diet, the MUFA and CARB diets significantly increased atherosclerosis in both sexes, but the PUFA diet had no effect. The MUFA and CARB diets also increased very low density lipoprotein-cholesterol (VLDL-C) and LDL-cholesterol (LDL-C) in males and VLDL-C levels in females. Analysis of data from LDLRKO mice on all diets showed that atherosclerotic lesion area correlated positively with VLDL-C levels (males: r = 0.47, P < 0.005; females: r = 0.52, P < 0.001). In contrast, in apoEKO mice there were no significant dietary effects on atherosclerosis in either sex. Compared with the SFA diet, the CARB diet significantly decreased VLDL-C in males and the MUFA, PUFA, and CARB diets decreased VLDL-C and the CARB diet decreased LDL-C in females. In summary, in LDLRKO mice the replacement of dietary SFA by either MUFA or CARB causes a proportionate increase in both atherosclerotic lesion area and VLDL-C. There were no significant dietary effects on atherosclerotic lesion area in apoEKO mice. These results are surprising and suggest that, depending on the underlying genotype, dietary MUFA and CARB can actually increase atherosclerosis susceptibility, probably by raising VLDL-C levels through a non-LDL receptor, apoE-dependent pathway.

  18. Compared with saturated fatty acids, dietary monounsaturated fatty acids and carbohydrates increase atherosclerosis and VLDL cholesterol levels in LDL receptor-deficient, but not apolipoprotein E-deficient, mice

    PubMed Central

    Merkel, Martin; Velez-Carrasco, Wanda; Hudgins, Lisa C.; Breslow, Jan L.

    2001-01-01

    Heart-healthy dietary recommendations include decreasing the intake of saturated fatty acids (SFA). However, the relative benefit of replacing SFA with monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), or carbohydrates (CARB) is still being debated. We have used two mouse models of atherosclerosis, low density lipoprotein receptor-deficient (LDLRKO) and apolipoprotein E-deficient (apoEKO) mice to measure the effects of four isocaloric diets enriched with either SFA, MUFA, PUFA, or CARB on atherosclerotic lesion area and lipoprotein levels. In LDLRKO mice, compared with the SFA diet, the MUFA and CARB diets significantly increased atherosclerosis in both sexes, but the PUFA diet had no effect. The MUFA and CARB diets also increased very low density lipoprotein-cholesterol (VLDL-C) and LDL-cholesterol (LDL-C) in males and VLDL-C levels in females. Analysis of data from LDLRKO mice on all diets showed that atherosclerotic lesion area correlated positively with VLDL-C levels (males: r = 0.47, P < 0.005; females: r = 0.52, P < 0.001). In contrast, in apoEKO mice there were no significant dietary effects on atherosclerosis in either sex. Compared with the SFA diet, the CARB diet significantly decreased VLDL-C in males and the MUFA, PUFA, and CARB diets decreased VLDL-C and the CARB diet decreased LDL-C in females. In summary, in LDLRKO mice the replacement of dietary SFA by either MUFA or CARB causes a proportionate increase in both atherosclerotic lesion area and VLDL-C. There were no significant dietary effects on atherosclerotic lesion area in apoEKO mice. These results are surprising and suggest that, depending on the underlying genotype, dietary MUFA and CARB can actually increase atherosclerosis susceptibility, probably by raising VLDL-C levels through a non-LDL receptor, apoE-dependent pathway. PMID:11606787

  19. Equol Attenuates Atherosclerosis in Apolipoprotein E-Deficient Mice by Inhibiting Endoplasmic Reticulum Stress via Activation of Nrf2 in Endothelial Cells

    PubMed Central

    Shi, Linying; Qin, Li; Zhang, Qianyong; Mi, Mantian

    2016-01-01

    The development of atherosclerosis is closely related to excessive endoplasmic reticulum stress (ERs). Equol reportedly protects against cardiovascular disease; however, the underlying mechanism for this protection remains unknown. Herein, the mechanisms contributing to the atheroprotective effect of equol were addressed using apolipoprotein E knockout (apoE-/-) mice fed a high-fat diet (HFD) with or without equol. Equol intervention reduced atherosclerotic lesions in the aorta in HFD-fed apoE-/- mice. Plasma lipid analysis showed that equol intervention reduced triglycerides, total cholesterol and LDL-cholesterol and increased HDL-cholesterol. Additionally, equol administration decreased lipid accumulation in the liver. Simultaneously, equol treatment inhibited cell apoptosis induced by t-BHP and thapsigargin in human umbilical vein endothelial cells (HUVECs). Furthermore, equol treatment attenuated palmitate, t-BHP or thapsigargin-induced upregulation of ER stress markers, including p-PERK, p-eIF2α, GRP78, ATF6 and CHOP proteins expression. The same tendency was also observed in aortic lysates in apoE-/- mice fed with equol plus HFD compared with HFD alone. Moreover, equol treatment dose dependently activated the Nrf2 signaling pathway under oxidative stress. Additionally, elevation of Nrf2 induction was found in aortic lysates in apoE-/- mice fed with a HFD diet containing equol compared with a HFD diet without equol. Importantly, Nrf2 siRNA interference induced CHOP and attenuated the effect of equol to inhibit t-BHP mediated CHOP induction, furthermore, abrogated cell apoptosis induced by t-BHP, suggesting a role for Nrf2 in the protective effect of equol in HUVECs. Collectively, these findings implicate that the improvement of atherosclerosis by equol through attenuation of ER stress is mediated, at least in part, by activating the Nrf2 signaling pathway. PMID:27907038

  20. ACAT inhibitor pactimibe sulfate (CS-505) reduces and stabilizes atherosclerotic lesions by cholesterol-lowering and direct effects in apolipoprotein E-deficient mice.

    PubMed

    Terasaka, Naoki; Miyazaki, Atsuhiro; Kasanuki, Naomi; Ito, Kayoko; Ubukata, Naoko; Koieyama, Tadashi; Kitayama, Ken; Tanimoto, Tatsuo; Maeda, Naoyuki; Inaba, Toshimori

    2007-02-01

    The objective of the present study was to determine whether a novel acyl-CoA:cholesterol acyltransferase (ACAT) inhibitor, pactimibe sulfate (CS-505), could reduce atherosclerotic lesions beyond and independent of the reduction achieved by cholesterol lowering alone from two different types of lesions. (1) Early lesion model. Twelve-week-old apolipoprotein E (apoE)(-/-) mice were treated with 0.03 or 0.1% (w/w) CS-505, 0.1 or 0.3% avasimibe (CI-1011), or 3% cholestyramine for 12 weeks. Each treatment significantly reduced plasma cholesterol by a similar degree (43-48%). The antiatherosclerotic activity of 0.1% CS-505, however, was more efficacious than the effects of the other treatments (90% versus 40-50%). (2) Advanced lesion model. Twenty-four-week-old apoE(-/-) mice were treated with 0.03 or 0.1% CS-505 or 0.1% CI-1011 for 12 weeks. CS-505 at 0.1% revealed enhanced lesion reduction compared with 0.1% CI-1011 (77% versus 54%), whereas the plasma cholesterol-lowering effect of 0.1% CS-505 was almost the same as that of 0.1% CI-1011. Furthermore, immunohistochemical analysis demonstrated that CS-505 significantly reduced the number of macrophages and expression of matrix metalloproteinase (MMP)-2, MMP-9, and MMP-13. These data indicate that CS-505 can reduce and stabilize atherosclerotic lesions. This antiatherosclerotic activity is exerted via both cholesterol lowering and direct ACAT inhibition in plaque macrophages.

  1. Dietary Soy Protein Isolate Ameliorates Atherosclerotic Lesions in Apolipoprotein E-Deficient Mice Potentially by Inhibiting Monocyte Chemoattractant Protein-1 Expression

    USDA-ARS?s Scientific Manuscript database

    Soy-based diets reportedly protect against the development of atherosclerosis; however, the underlying mechanism(s) for this protection remains unknown. In this report, the mechanism(s) contributing to the atheroprotective effects of a soy-based diet was addressed using the apolipoprotein E knockout...

  2. Impact of estrogens on atherosclerosis and bone in the apolipoprotein E-deficient mouse model.

    PubMed

    Fernández-Murga, María Leonor; Vinué, Ángela; Caeiro, José Ramón; Guede, David; Tarín, Juan J; Andrés, Vicente; Cano, Antonio

    2015-04-01

    The common inflammatory pathophysiology has nourished the hypothesis of a relationship between osteoporosis and cardiovascular disease. Estrogens are key agents in the modulation of both processes. We investigated whether induction of atherosclerosis affects bone and whether estrogens modulate both processes. Female apolipoprotein E-deficient mice (a well-established model of atherogenesis) were ovariectomized or falsely operated and fed either standard diet or high-fat diet (HFD). Six animals were included in each of the four groups. To clarify mechanisms, we treated preosteoblastic MC3T3-E1 cells with mouse serum. Physiological levels of estrogens in falsely operated mice limited atherosclerotic burden in the thoracic aorta, but not in the aortic arch. Bone resorption, as assessed by C-telopeptides, was increased by ovariectomy in animals fed standard diet, but not in animals fed HFD. Bone microstructural properties at the distal femur showed deteriorated trabecular architecture in bone volumetric fraction and trabecular number after ovariectomy, but trabecular pattern factor, trabecular thickness, trabecular spacing, or the structural model index remained unchanged. Changes in cortical parameters were not significant. Volumetric bone mineral density was reduced in trabecular bone, but not in cortical bone, in ovariectomized mice fed standard diet. Preosteoblastic MC3T3-E1 cells exhibited increased cellular proliferation and viability and alkaline phosphatase activity after treatment with sera from animals fed HFD. Endogenous estrogens partially reduce atherogenic burden in female apolipoprotein E-deficient mice. Ovariectomy increases bone resorption, but not under exacerbated proatherogenic conditions induced by HFD. The absence of apolipoprotein E might have an influence on the asymmetric responses of atherogenesis and bone resorption.

  3. Differential effect of walnut oil and safflower oil on the serum cholesterol level and lesion area in the aortic root of apolipoprotein E-deficient mice.

    PubMed

    Iwamoto, Masako; Kono, Misaki; Kawamoto, Daisuke; Tomoyori, Hiroko; Sato, Masao; Imaizumi, Katsumi

    2002-01-01

    Walnut oil (WO) is a good source of alpha-linolenic acid. We compared the effects of WO and high-linoleic safflower oil (HLSO) on the serum lipid level and atherosclerosis development in male and female apolipoprotein (apo) E-deficient mice. The WO diet resulted in a higher level of serum cholesterol than with HLSO. Female mice fed on the WO diet had a greater lesion area in the aortic root than did those on the HLSO diet. There was no diet-dependent difference in the level of cholesterol and its oxidation products in the abdominal and thoracic aorta. These results suggest that the unpleasant effects of the WO diet on apo E-deficient mice may be attributable to alpha-linolenic acid.

  4. [Atorvastatin inhibits the atherosclerotic lesion induced by tumor necrosis factor-like weak inducer of apoptosis in apolipoprotein E deficient mice].

    PubMed

    Fernández-Laso, Valvanera; Sastre, Cristina; Egido, Jesús; Martín-Ventura, Jose L; Blanco-Colio, Luis M

    2015-01-01

    Interaction of tumor necrosis factor-like weak inducer of apoptosis (TWEAK) with its receptor Fn14 accelerates atherosclerotic plaque development in ApoE deficient mice (ApoE KO). In this work, an analysis has been made on the effect of an HMG-CoA reductase inhibitor, atorvastatin, on atherosclerotic plaque development accelerated by TWEAK in ApoE KO mice. Eight week-old ApoE KO mice were fed with a high cholesterol diet for 4 weeks. The animals were then randomized into 3 groups: mice injected i.p. with saline, recombinant TWEAK (10 μg/kg/twice a week), or recombinant TWEAK plus atorvastatin (1 mg/kg/day) for 4 weeks. The lesion size, cellular composition, lipid and collagen content were analyzed, as well as inflammatory response in atherosclerotic plaques present in aortic root of mice. TWEAK treated mice showed an increase in atherosclerotic plaque size, as well as in collagen/lipid ratio compared with control mice. In addition, macrophage content, MCP-1 and RANTES expression, and NF-κB activation were augmented in atherosclerotic plaques present in aortic root of TWEAK treated mice compared with control mice. Treatment with atorvastatin prevented all these changes induced by TWEAK in atherosclerotic lesions. Atorvastatin treatment also decreased Fn14 expression in the atherosclerotic plaques of ApoE KO mice. Atorvastatin prevents the pro-atherogenic effects induced by TWEAK in ApoE KO mice, which could be related to the inhibition of Fn14 expression. The results of this study provide new information on the beneficial effects of statin treatment in cardiovascular diseases. Copyright © 2014 Sociedad Española de Arteriosclerosis. Published by Elsevier España. All rights reserved.

  5. Absence of apolipoprotein E protects mice from cerebral malaria

    PubMed Central

    Kassa, Fikregabrail Aberra; Van Den Ham, Kristin; Rainone, Anthony; Fournier, Sylvie; Boilard, Eric; Olivier, Martin

    2016-01-01

    Cerebral malaria claims the life of millions of people each year, particularly those of children, and is a major global public health problem. Thus, the identification of novel malaria biomarkers that could be utilized as diagnostic or therapeutic targets is becoming increasingly important. Using a proteomic approach, we previously identified unique biomarkers in the sera of malaria-infected individuals, including apolipoprotein E (ApoE). ApoE is the dominant apolipoprotein in the brain and has been implicated in several neurological disorders; therefore, we were interested in the potential role of ApoE in cerebral malaria. Here we report the first demonstration that cerebral malaria is markedly attenuated in ApoE−/− mice. The protection provided by the absence of ApoE was associated with decreased sequestration of parasites and T cells within the brain, and was determined to be independent from the involvement of ApoE receptors and from the altered lipid metabolism associated with the knock-out mice. Importantly, we demonstrated that treatment of mice with the ApoE antagonist heparin octasaccharide significantly decreased the incidence of cerebral malaria. Overall, our study indicates that the reduction of ApoE could be utilized in the development of therapeutic treatments aimed at mitigating the neuropathology of cerebral malaria. PMID:27647324

  6. Absence of apolipoprotein E protects mice from cerebral malaria.

    PubMed

    Kassa, Fikregabrail Aberra; Van Den Ham, Kristin; Rainone, Anthony; Fournier, Sylvie; Boilard, Eric; Olivier, Martin

    2016-09-20

    Cerebral malaria claims the life of millions of people each year, particularly those of children, and is a major global public health problem. Thus, the identification of novel malaria biomarkers that could be utilized as diagnostic or therapeutic targets is becoming increasingly important. Using a proteomic approach, we previously identified unique biomarkers in the sera of malaria-infected individuals, including apolipoprotein E (ApoE). ApoE is the dominant apolipoprotein in the brain and has been implicated in several neurological disorders; therefore, we were interested in the potential role of ApoE in cerebral malaria. Here we report the first demonstration that cerebral malaria is markedly attenuated in ApoE(-/-) mice. The protection provided by the absence of ApoE was associated with decreased sequestration of parasites and T cells within the brain, and was determined to be independent from the involvement of ApoE receptors and from the altered lipid metabolism associated with the knock-out mice. Importantly, we demonstrated that treatment of mice with the ApoE antagonist heparin octasaccharide significantly decreased the incidence of cerebral malaria. Overall, our study indicates that the reduction of ApoE could be utilized in the development of therapeutic treatments aimed at mitigating the neuropathology of cerebral malaria.

  7. Simvastatin inhibited cardiac hypertrophy and fibrosis in apolipoprotein E-deficient mice fed a "Western-style diet" by increasing PPAR α and γ expression and reducing TC, MMP-9, and Cat S levels.

    PubMed

    Qin, Yan-wen; Ye, Ping; He, Ji-qiang; Sheng, Li; Wang, Lu-ya; Du, Jie

    2010-10-01

    The examine the cardiac hypertrophy and fibrosis in apolipoprotein E-deficient mice (ApoE-/- mice) fed a "Western-style diet" and the effect of simvastatin intervention. Male ApoE-/- mice (n=36) were fed a "Western-style diet" from the age of 8 weeks. After 16 weeks, they were randomly given either simvastatin (25 mg·kg⁻¹·d⁻¹) or normal saline (control group) by gavage for 8, 16, or 24 weeks. The left ventricular (LV) wall thickness and diameter of the myocardial cells were determined with Hematoxylin-Eosin stain, and the level of fibrosis of the myocardial matrix was assessed with Masson stain. Real-time quantitative polymerase chain reaction and Western blotting analysis were used to determine the mRNA and protein expression of matrix metalloproteinase-9 (MMP-9), Cathepsin S (Cat S), and the peroxisome proliferator-activated receptors (PPARs) in the myocardium of ApoE-/- mice. ApoE-/- mice fed a "Western-style diet" showed an significant age-dependent increase in total cholesterol (TC), LV wall thickness, myocardial cell diameter and LV collagen content (P<0.05). The simvastatin treatment group showed significantly reduced LV wall thickness, myocardial cell diameters and LV collagen content at 40 weeks when compared with the control group (P<0.05). Furthermore, treatment with simvastatin also significantly inhibited the mRNA and protein expressions of MMP-9 and Cat S as well as increased the mRNA and protein expressions of PPAR alpha and PPAR gamma at 32 and 40 weeks compared with the control group (P<0.05). ApoE-/- mice fed a "Western-style diet" had cardiac hypertrophy and fibrosis, which worsened with age. Simvastatin treatment inhibits the development of cardiac hypertrophy and fibrosis, and this effect may be mediated through increased levels of PPAR alpha and PPAR gamma and reduced levels of TC, MMP-9, and Cat S.

  8. Glucagon-like peptide-1 analogue liraglutide ameliorates atherogenesis via inhibiting advanced glycation end product-induced receptor for advanced glycosylation end product expression in apolipoprotein-E deficient mice.

    PubMed

    Li, Peicheng; Tang, Zhaosheng; Wang, Lin; Feng, Bo

    2017-09-01

    Glucagon-like peptide-1 (GLP-1) can protect arteriosclerotic lesions in apolipoprotein-E deficient (ApoE-/-) mice. Advanced glycation end products (AGEs)/receptor for advanced glycation end products (RAGE) interaction serves a key role in the development of diabetic vascular complications. The present study examined whether the GLP-1 analogue liraglutide can ameliorate atherogenesis via inhibiting AGEs-induced RAGE expression. Male ApoE-/- mice (age, 10 weeks) were divided into control, GLP-1, AGEs and AGEs+GLP-1 group. All mice were fed a high-fat diet. The AGEs and AGEs+GLP-1 groups were treated with intraperitoneal injection of AGEs (30 mg/kg/day). The GLP-1 and AGEs+GLP-1 groups were treated with subcutaneous injections of liraglutide (0.4 mg/kg/day). After 9 weeks, blood was drawn and the aortas were rapidly procured. The serum levels of AGEs, soluble RAGE (sRAGE), stromal cell-derived factor-1α (SDF-1α), total cholesterol and triacylglycerol were measured. Atherosclerotic plaque area was determined by Sudan IV staining. The mRNA and protein expression levels of RAGE were determined using reverse transcription-quantitative polymerase chain reaction and western blotting, respectively. The results demonstrated that AGEs treatment increased serum AGEs levels, increased the expression of RAGE in the aorta, and aggravated atherosclerotic lesions compared with the control. Liraglutide treatment reduced serum AGEs levels, reduced the expression of RAGE in aorta, and relieved atherosclerotic lesions compared with the control. In conclusion, these data suggested that liraglutide serves an anti-atherosclerotic effect via inhibiting AGEs-induced RAGE expression in ApoE-/- mice. These findings provide novel evidence for the use of GLP-1-type agents for the treatment of diabetic vascular complications.

  9. Exercise training reduces severity of atherosclerosis in apolipoprotein E knockout mice via nitric oxide.

    PubMed

    Shimada, Kana; Kishimoto, Chiharu; Okabe, Taka-aki; Hattori, Miki; Murayama, Toshinori; Yokode, Masayuki; Kita, Toru

    2007-07-01

    Exercise training may protect against the development of atherosclerosis, although the precise mechanisms are still unknown. The present study assessed the hypothesis that exercise training would reduce the severity of experimental atherosclerosis in apolipoprotein-E (apoE)-deficient mice via nitric oxide (NO). ApoE-deficient mice fed a high-fat diet underwent exercise training (30 min swimming) 3 times per week for 8 weeks. The exercise group were also given oral N(G)-nitro-L-arginine methylester (L-NAME; 25 mg x kg (-1) x day(-1)), an inhibitor of NO synthase. Fatty streak plaque lesions developed in ApoE-deficient mice fed the high-fat diet, and were suppressed in the mice that underwent swimming training. In contrast, atherosclerotic lesions were not ameliorated in mice that had exercise training plus oral L-NAME treatment. Immunohistochemical analysis revealed that the expression of endothelial NO increased in mice undergoing exercise compared with the mice that did not exercise, and that the expression was suppressed in the mice having exercise plus oral L-NAME treatment. Differences in lesion area did not correlate with any significant alterations in serum lipid levels. Exercise training suppressed atherosclerosis via the NO system.

  10. Betaine supplement alleviates hepatic triglyceride accumulation of apolipoprotein E deficient mice via reducing methylation of peroxisomal proliferator-activated receptor alpha promoter.

    PubMed

    Wang, Lijun; Chen, Li; Tan, Yaozong; Wei, Jun; Chang, Ying; Jin, Tianru; Zhu, Huilian

    2013-03-13

    Betaine is a methyl donor and has been considered as a lipotropic effect substance. But its mechanism remains unclear. Hepatic steatosis is associated with abnormal expression of genes involved in hepatic lipid metabolism. DNA methylation contributes to the disregulation of gene expression. Here we hypothesized that betaine supplement and subsequent DNA methylation modifications alter the expression of genes that are involved in hepatic lipid metabolism and hence alleviate hepatic triglyceride accumulation. Male wild-type (WT) C57BL/6 mice (n = 6) were fed with the AIN-93 G diet. ApoE-/- mice (n = 12), weight-matched with the WT mice, were divided into two groups (n = 6 per group), and fed with the AIN-93 G diet and AIN-93 G supplemented with 2% betaine/100 g diet. Seven weeks after the intervention, mice were sacrificed. Liver betaine, choline, homocysteine concentration were measured by HPLC. Liver oxidants activity and triglyceride level were assessed by ultraviolet spectrophotometry. Finally, hepatic PPAR alpha gene and its target genes expression levels and the methylation status of the PPAR alpha gene were determined. ApoE-/- mice had higher hepatic triglyceride and lower GSH-Px activity when compared with the WT mice. Betaine intervention reversed triglyceride deposit, enhanced SOD and GSH-Px activity in the liver. Interestingly, mice fed on betaine-supplemented diet showed a dramatic increase of hepatic choline concentration and a decrease of betaine and homocysteine concentration relative to the WT mice and the ApoE-/- mice absent with betaine intervention. Expression of PPAR alpha and CPT1 were decreased and expression of FAS was markedly increased in ApoE-/- mice. In parallel, PPAR alpha promoter methylation level were slightly increased in ApoE-/- mice though without significance. Betaine supplement upregulated expression of PPAR alpha and its target genes (CPT1, CYP2E1) and reversed hypermethylation of PPAR alpha promoter of ApoE-/- mice. Furthermore

  11. Betaine supplement alleviates hepatic triglyceride accumulation of apolipoprotein E deficient mice via reducing methylation of peroxisomal proliferator-activated receptor alpha promoter

    PubMed Central

    2013-01-01

    Background Betaine is a methyl donor and has been considered as a lipotropic effect substance. But its mechanism remains unclear. Hepatic steatosis is associated with abnormal expression of genes involved in hepatic lipid metabolism. DNA methylation contributes to the disregulation of gene expression. Here we hypothesized that betaine supplement and subsequent DNA methylation modifications alter the expression of genes that are involved in hepatic lipid metabolism and hence alleviate hepatic triglyceride accumulation. Methods Male wild-type (WT) C57BL/6 mice (n = 6) were fed with the AIN-93 G diet. ApoE−/− mice (n = 12), weight-matched with the WT mice, were divided into two groups (n = 6 per group), and fed with the AIN-93 G diet and AIN-93 G supplemented with 2% betaine/100 g diet. Seven weeks after the intervention, mice were sacrificed. Liver betaine, choline, homocysteine concentration were measured by HPLC. Liver oxidants activity and triglyceride level were assessed by ultraviolet spectrophotometry. Finally, hepatic PPAR alpha gene and its target genes expression levels and the methylation status of the PPAR alpha gene were determined. Results ApoE−/− mice had higher hepatic triglyceride and lower GSH-Px activity when compared with the WT mice. Betaine intervention reversed triglyceride deposit, enhanced SOD and GSH-Px activity in the liver. Interestingly, mice fed on betaine-supplemented diet showed a dramatic increase of hepatic choline concentration and a decrease of betaine and homocysteine concentration relative to the WT mice and the ApoE−/− mice absent with betaine intervention. Expression of PPAR alpha and CPT1 were decreased and expression of FAS was markedly increased in ApoE−/− mice. In parallel, PPAR alpha promoter methylation level were slightly increased in ApoE−/− mice though without significance. Betaine supplement upregulated expression of PPAR alpha and its target genes (CPT1, CYP2E1) and reversed

  12. Simvastatin inhibited cardiac hypertrophy and fibrosis in apolipoprotein E-deficient mice fed a “Western-style diet” by increasing PPAR α and γ expression and reducing TC, MMP-9, and Cat S levels

    PubMed Central

    Qin, Yan-wen; Ye, Ping; He, Ji-qiang; Sheng, Li; Wang, Lu-ya; Du, Jie

    2010-01-01

    Aim: The examine the cardiac hypertrophy and fibrosis in apolipoprotein E-deficient mice (ApoE−/− mice) fed a “Western-style diet” and the effect of simvastatin intervention. Methods: Male ApoE−/− mice (n=36) were fed a “Western-style diet” from the age of 8 weeks. After 16 weeks, they were randomly given either simvastatin (25 mg·kg−1·d−1) or normal saline (control group) by gavage for 8, 16, or 24 weeks. The left ventricular (LV) wall thickness and diameter of the myocardial cells were determined with Hematoxylin-Eosin stain, and the level of fibrosis of the myocardial matrix was assessed with Masson stain. Real-time quantitative polymerase chain reaction and Western blotting analysis were used to determine the mRNA and protein expression of matrix metalloproteinase-9 (MMP-9), Cathepsin S (Cat S), and the peroxisome proliferator-activated receptors (PPARs) in the myocardium of ApoE−/− mice. Results: ApoE−/− mice fed a “Western-style diet” showed an significant age-dependent increase in total cholesterol (TC), LV wall thickness, myocardial cell diameter and LV collagen content (P<0.05). The simvastatin treatment group showed significantly reduced LV wall thickness, myocardial cell diameters and LV collagen content at 40 weeks when compared with the control group (P<0.05). Furthermore, treatment with simvastatin also significantly inhibited the mRNA and protein expressions of MMP-9 and Cat S as well as increased the mRNA and protein expressions of PPAR alpha and PPAR gamma at 32 and 40 weeks compared with the control group (P<0.05). Conclusion: ApoE−/− mice fed a “Western-style diet” had cardiac hypertrophy and fibrosis, which worsened with age. Simvastatin treatment inhibits the development of cardiac hypertrophy and fibrosis, and this effect may be mediated through increased levels of PPAR alpha and PPAR gamma and reduced levels of TC, MMP-9, and Cat S. PMID:20835264

  13. Mobilization of sca1/flk-1 positive endothelial progenitor cells declines in apolipoprotein E-deficient mice with a high-fat diet.

    PubMed

    Steinmetz, Martin; Lucanus, Eva; Zimmer, Sebastian; Nickenig, Georg; Werner, Nikos

    2015-12-01

    Atherosclerosis features a deterioration of the endothelial layer in all stages. Restoration of the endothelium is associated with circulating stem cell antigen 1 (sca1) and vascular endothelial growth factor receptor type 2 (flk-1) positive endothelial progenitor cells (EPCs). We investigated whether EPC production and/or a mobilization from bone marrow are reduced in severe atherosclerosis. EPCs in peripheral blood were diminished in ApoE-/- mice with high-fat diet (HFD) whereas bone marrow levels of these cells were not significantly altered compared to controls. In situ perfusion of the hind limbs demonstrated that EPC mobilization was reduced compared to ApoE-/- mice with normal chow, although increased plasma stromal cell-derived factor (SDF) 1α and responsivity suggested a mobilizing stimulus. The proliferation of sca1/flk-1 positive cells showed no functional impairment. EPCs could not only be significantly mobilized from the bone marrow through the application of granulocyte colony stimulating factor (GCSF), but also led by trend to a depletion of the bone marrow pool. GCSF levels in plasma were equal in ApoE-/- mice with normal chow or HFD, which excluded a decline in GCSF production. The capability of the bone marrow pool to adapt the proliferation and mobilization of sca1/flk-1 positive EPCs seems overstrained in ApoE-/- mice with a HFD. Copyright © 2015 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

  14. Genetic and Pharmacological Modifications of Thrombin Formation in Apolipoprotein E-deficient Mice Determine Atherosclerosis Severity and Atherothrombosis Onset in a Neutrophil-Dependent Manner

    PubMed Central

    Borissoff, Julian I.; Otten, Jeroen J. T.; Heeneman, Sylvia; Leenders, Peter; van Oerle, René; Soehnlein, Oliver; Loubele, Sarah T. B. G.; Hamulyák, Karly; Hackeng, Tilman M.; Daemen, Mat J. A. P.; Degen, Jay L.; Weiler, Hartmut; Esmon, Charles T.; van Ryn, Joanne; Biessen, Erik A. L.; Spronk, Henri M. H.; ten Cate, Hugo

    2013-01-01

    Background Variations in the blood coagulation activity, determined genetically or by medication, may alter atherosclerotic plaque progression, by influencing pleiotropic effects of coagulation proteases. Published experimental studies have yielded contradictory findings on the role of hypercoagulability in atherogenesis. We therefore sought to address this matter by extensively investigating the in vivo significance of genetic alterations and pharmacologic inhibition of thrombin formation for the onset and progression of atherosclerosis, and plaque phenotype determination. Methodology/Principal Findings We generated transgenic atherosclerosis-prone mice with diminished coagulant or hypercoagulable phenotype and employed two distinct models of atherosclerosis. Gene-targeted 50% reduction in prothrombin (FII−/WT:ApoE−/−) was remarkably effective in limiting disease compared to control ApoE−/− mice, associated with significant qualitative benefits, including diminished leukocyte infiltration, altered collagen and vascular smooth muscle cell content. Genetically-imposed hypercoagulability in TMPro/Pro:ApoE−/− mice resulted in severe atherosclerosis, plaque vulnerability and spontaneous atherothrombosis. Hypercoagulability was associated with a pronounced neutrophilia, neutrophil hyper-reactivity, markedly increased oxidative stress, neutrophil intraplaque infiltration and apoptosis. Administration of either the synthetic specific thrombin inhibitor Dabigatran etexilate, or recombinant activated protein C (APC), counteracted the pro-inflammatory and pro-atherogenic phenotype of pro-thrombotic TMPro/Pro:ApoE−/− mice. Conclusions/Significance We provide new evidence highlighting the importance of neutrophils in the coagulation-inflammation interplay during atherogenesis. Our findings reveal that thrombin-mediated proteolysis is an unexpectedly powerful determinant of atherosclerosis in multiple distinct settings. These studies suggest that selective

  15. Overexpression of Prolyl-4-Hydroxylase-α1 Stabilizes but Increases Shear Stress-Induced Atherosclerotic Plaque in Apolipoprotein E-Deficient Mice

    PubMed Central

    Liu, Xin-xin; Li, Meng-meng; Zhang, Yu; Chen, Liang; Wang, Lin; Di, Ming-xue

    2016-01-01

    The rupture and erosion of atherosclerotic plaque can induce coronary thrombosis. Prolyl-4-hydroxylase (P4H) plays a central role in the synthesis of all known types of collagens, which are the most abundant constituent of the extracellular matrix in atherosclerotic plaque. The pathogenesis of atherosclerosis is thought to be in part caused by shear stress. In this study, we aimed to investigate a relationship between P4Hα1 and shear stress-induced atherosclerotic plaque. Carotid arteries of ApoE−/− mice were exposed to low and oscillatory shear stress conditions by the placement of a shear stress cast for 2 weeks; we divided 60 male ApoE−/− mice into three groups for treatments with saline (mock) (n = 20), empty lentivirus (lenti-EGFP) (n = 20), and lentivirus-P4Hα1 (lenti-P4Hα1) (n = 20). Our results reveal that after 2 weeks of lenti-P4Hα1 treatment both low and oscillatory shear stress-induced plaques increased collagen and the thickness of fibrous cap and decreased macrophage accumulation but no change in lipid accumulation. We also observed that overexpression of P4Ha1 increased plaque size. Our study suggests that P4Hα1 overexpression might be a potential therapeutic target in stabilizing vulnerable plaques. PMID:27818566

  16. Angiotensin type 2-receptor (AT2R) activation induces hypotension in apolipoprotein E-deficient mice by activating peroxisome proliferator-activated receptor-γ.

    PubMed

    Li, Ming; Tejada, Thor; Lambert, Jonathan P; Nicholson, Chad K; Yahiro, Eiji; Ambai, Vats T; Ali, Syeda F; Bradley, Eddie W; Graham, Robert M; Dell'Italia, Louis J; Calvert, John W; Naqvi, Nawazish

    2016-01-01

    Angiotensin II (Ang II) modulates blood pressure and atherosclerosis development through its vascular type-1 (AT1R) and type-2 (AT2R) receptors, which have opposing effects. AT2R activation produces hypotension, and is anti-atherogenic. Targeted overexpression of AT2Rs in vascular smooth muscle cells (VSMCs) indicates that these effects are due to increased nitric oxide (NO) generation. However, the role of endogenous VSMC AT2Rs in these events is unknown. Effect of 7-day low-dose Ang II-infusion (12 µg/kg/hr) on blood pressure was tested in 9-week-old apoE((-/-)) mice fed a low or high cholesterol diet (LCD or HCD, respectively). Cardiac output was measured by echocardiography. Immunohistochemistry was performed to localize and quantify AT2Rs and p-Ser(1177)-endothelial nitric oxide synthase (eNOS) levels in the aortic arch. PD123319 and GW-9662 were used to selectively block the AT2R and peroxisome proliferator-activated receptor-γ (PPAR-γ), respectively. Ang II infusion decreased blood pressure by 12 mmHg (P < 0.001) in LCD/apoE((-/-)) mice without altering cardiac output; a response blocked by PD123319. Although, AT2R stimulation neither activated eNOS (p-Ser(1177)-eNOS) nor changed plasma NO metabolites, it caused an ~6-fold increase in VSMC PPAR-γ levels (P < 0.001) and the AT2R-mediated hypotension was abolished by GW-9662. AT2R-mediated hypotension was also inhibited by HCD, which selectively decreased VSMC AT2R expression by ~6-fold (P < 0.01). These findings suggest a novel pathway for the Ang II/AT2R-mediated hypotensive response that involves PPAR-γ, and is down regulated by a HCD.

  17. Olive oils modulate fatty acid content and signaling protein expression in apolipoprotein E knockout mice brain.

    PubMed

    Alemany, Regina; Navarro, María A; Vögler, Oliver; Perona, Javier S; Osada, Jesús; Ruiz-Gutiérrez, Valentina

    2010-01-01

    Atherosclerosis contributes to disruption of neuronal signaling pathways by producing lipid-dependent modifications of brain plasma membranes, neuroinflammation and oxidative stress. We investigated whether long-term (11 weeks) consumption of refined- (ROO) and pomace- (POO) olive oil modulated the fatty acid composition and the levels of membrane signaling proteins in the brain of apolipoprotein E (apoE) knockout (KO) mice, an animal model of atherosclerosis. Both of these oils are rich in bioactive molecules with anti-inflammatory and antioxidant effects. ROO and POO long-term consumption increased the proportion of monounsaturated fatty acids (MUFAs), particularly of oleic acid, while reducing the level of the saturated fatty acids (SFAs) palmitic and stearic acid. As a result, the MUFA:SFA ratio was higher in apoE KO mice brain fed with ROO and POO. Furthermore, both oils reduced the level of arachidonic and eicosapentaenoic acid, suggesting a decrease in the generation of pro- and anti-inflammatory eicosanoids. Finally, ROO and POO induced an increase in the density of membrane proteins implicated in both the Galphas/PKA and Galphaq/PLCbeta1/PKCalpha signaling pathways. The combined effects of long-term ROO and POO consumption on fatty acid composition and the level of signaling proteins involved in PKA and PKC activation, suggest positive effects on neuroinflammation and brain function in apoE KO mice brain, and convert these oils into promising functional foods in diseases involving apoE deficiency.

  18. Modulation of autoimmune arthritis severity in mice by apolipoprotein E (ApoE) and cholesterol.

    PubMed

    Alvarez, P; Genre, F; Iglesias, M; Augustin, J J; Tamayo, E; Escolà-Gil, J C; Lavín, B; Blanco-Vaca, F; Merino, R; Merino, J

    2016-12-01

    Apolipoprotein E (ApoE) deficiency promoted an exacerbation of autoimmune arthritis in mice by inducing proinflammatory immune responses. In this study we analysed the contribution of hypercholesterolaemia and/or the absence of ApoE anti-inflammatory properties, unrelated to its function in the control of cholesterol metabolism, towards the acceleration of arthritis in these mutant animals. The induction and severity of collagen type II-induced arthritis (CIA) were compared for B10.RIII wild-type (WT), B10.RIII.ApoE(+/-) , B10.RIII.ApoE(-/-) and B10.RIII.low-density lipoprotein receptor (LDLR(-/-) ) mice with different concentrations of circulating ApoE and cholesterol. A 50-70% reduction in serum levels of ApoE was observed in heterozygous B10.RIII.ApoE(+/-) mice in comparison to B10.RIII.WT, although both strains of mice exhibited similar circulating lipid profiles. This ApoE reduction was associated with an increased CIA severity that remained lower than in homozygous B10.RIII.ApoE(-/-) mice. An important rise in circulating ApoE concentration was observed in hypercholesterolaemic B10.RIII.LDLR(-/-) mice fed with a normal chow diet, and both parameters increased further with an atherogenic hypercholesterolaemic diet. However, the severity of CIA in B10.RIII.LDLR(-/-) mice was similar to that of B10.RIII.WT controls. In conclusion, by comparing the evolution of CIA between several strains of mutant mice with different levels of serum ApoE and cholesterol, our results demonstrate that both hypercholesterolaemia and ApoE regulate the intensity of in-vivo systemic autoimmune responses. © 2016 British Society for Immunology.

  19. Cellular Source of Apolipoprotein E4 Determines Neuronal Susceptibility to Excitotoxic Injury in Transgenic Mice

    PubMed Central

    Buttini, Manuel; Masliah, Eliezer; Yu, Gui-Qiu; Palop, Jorge J.; Chang, Shengjun; Bernardo, Aubrey; Lin, Carol; Wyss-Coray, Tony; Huang, Yadong; Mucke, Lennart

    2010-01-01

    The lipid transport protein apolipoprotein E (apoE) is abundantly expressed in the brain. Its main isoforms in humans are apoE2, apoE3, and apoE4. ApoE4 is the major known genetic risk factor for Alzheimer’s disease and also contributes to the pathogenesis of various other neurological conditions. In the central nervous system, apoE is synthesized by glial cells and neurons, but it is unclear whether the cellular source affects its biological activities. To address this issue, we induced excitotoxic injury by systemic kainic acid injection in transgenic Apoe knockout mice expressing human apoE isoforms in astrocytes or neurons. Regardless of its cellular source, apoE3 expression protected neuronal synapses and dendrites against the excitotoxicity seen in apoE-deficient mice. Astrocyte-derived apoE4, which has previously been shown to have detrimental effects in vitro, was as excitoprotective as apoE3 in vivo. In contrast, neuronal expression of apoE4 was not protective and resulted in loss of cortical neurons after excitotoxic challenge, indicating that neuronal apoE4 promotes excitotoxic cell death. Thus, an imbalance between astrocytic (excitoprotective) and neuronal (neurotoxic) apoE4 expression may increase susceptibility to diverse neurological diseases involving excitotoxic mechanisms. PMID:20595630

  20. Cellular source of apolipoprotein E4 determines neuronal susceptibility to excitotoxic injury in transgenic mice.

    PubMed

    Buttini, Manuel; Masliah, Eliezer; Yu, Gui-Qiu; Palop, Jorge J; Chang, Shengjun; Bernardo, Aubrey; Lin, Carol; Wyss-Coray, Tony; Huang, Yadong; Mucke, Lennart

    2010-08-01

    The lipid transport protein apolipoprotein E (apoE) is abundantly expressed in the brain. Its main isoforms in humans are apoE2, apoE3, and apoE4. ApoE4 is the major known genetic risk factor for Alzheimer's disease and also contributes to the pathogenesis of various other neurological conditions. In the central nervous system, apoE is synthesized by glial cells and neurons, but it is unclear whether the cellular source affects its biological activities. To address this issue, we induced excitotoxic injury by systemic kainic acid injection in transgenic Apoe knockout mice expressing human apoE isoforms in astrocytes or neurons. Regardless of its cellular source, apoE3 expression protected neuronal synapses and dendrites against the excitotoxicity seen in apoE-deficient mice. Astrocyte-derived apoE4, which has previously been shown to have detrimental effects in vitro, was as excitoprotective as apoE3 in vivo. In contrast, neuronal expression of apoE4 was not protective and resulted in loss of cortical neurons after excitotoxic challenge, indicating that neuronal apoE4 promotes excitotoxic cell death. Thus, an imbalance between astrocytic (excitoprotective) and neuronal (neurotoxic) apoE4 expression may increase susceptibility to diverse neurological diseases involving excitotoxic mechanisms.

  1. Hyperlipidemia Impaired Innate Immune Response to Periodontal Pathogen Porphyromonas gingivalis in Apolipoprotein E Knockout Mice

    PubMed Central

    Yan, Fuhua; Xiao, Yin

    2013-01-01

    A finely-tuned innate immune response plays a pivotal role in protecting host against bacterial invasion during periodontal disease progression. Hyperlipidemia has been suggested to exacerbate periodontal health condition. However, the underlying mechanism has not been addressed. In the present study, we investigated the effect of hyperlipidemia on innate immune responses to periodontal pathogen Porphyromonas gingivalis infection. Apolipoprotein E-deficient and wild-type mice at the age of 20 weeks were used for the study. Peritoneal macrophages were isolated and subsequently used for the study of viable P. gingivalis infection. ApoE−/− mice demonstrated inhibited iNOS production and impaired clearance of P. gingivalis in vitro and in vivo; furthermore, ApoE−/− mice displayed disrupted cytokine production pattern in response to P. gingivalis, with a decreased production of tumor necrosis factor-α, interleukin-6 (IL-6), IL-1β and monocyte chemotactic protein-1. Microarray data demonstrated that Toll-like receptor (TLR) and NOD-like receptor (NLR) pathway were altered in ApoE−/− mice macrophages; further analysis of pattern recognition receptors (PRRs) demonstrated that expression of triggering receptors on myeloid cells-1 (TREM-1), an amplifier of the TLR and NLR pathway, was decreased in ApoE−/− mice macrophages, leading to decreased recruitment of NF-κB onto the promoters of the TNF-α and IL-6. Our data suggest that in ApoE−/− mice hyperlipidemia disrupts the expression of PRRs, and cripples the host’s capability to generate sufficient innate immune response to P. gingivalis, which may facilitate immune evasion, subgingival colonization and establishment of P. gingivalis in the periodontal niche. PMID:23977160

  2. Aspirin-triggered lipoxin A4 inhibits atherosclerosis progression in apolipoprotein E(-/-) mice.

    PubMed

    Petri, Marcelo H; Laguna-Fernandez, Andrés; Arnardottir, Hildur; Wheelock, Craig E; Perretti, Mauro; Hansson, Göran K; Bäck, Magnus

    2017-01-10

    Atherosclerosis is characterized by a chronic non-resolving inflammation in the arterial wall. Aspirin-triggered lipoxin A4 (ATL) is a potent anti-inflammatory mediator, involved in the resolution of inflammation. However, the therapeutic potential of immune targeting by means of ATL in atherosclerosis has not previously been explored. The aim of the present study was to determine the effects of ATL and its receptor Fpr2 on atherosclerosis development and progression in apolipoprotein E deficient (ApoE(-/-) ) mice. ApoE(-/-)  × Fpr2(+/+) and ApoE(-/-)  × Fpr2(-/-) mice were generated. Four-week-old mice fed a high-fat diet for 4 weeks and 16-week-old mice fed chow diet received osmotic pumps containing either vehicle or ATL for 4 weeks. Atherosclerotic lesion size and cellular composition were measured in the aortic root and thoracic aorta. Lipid levels and leukocyte counts were measured in blood and mRNA was isolated from abdominal aorta and spleen. ATL blocked atherosclerosis progression in the aortic root and thoracic aorta of ApoE(-/-) mice. In addition, ATL reduced macrophage infiltration and apoptotic cells in atherosclerotic lesions. The mRNA levels of several cytokines and chemokines in the spleen and aorta were reduced by ATL, whereas circulating leukocyte levels were unchanged. The ATL-induced athero-protection was absent in ApoE(-/-) mice lacking the Fpr2 receptor. ATL blocked atherosclerosis progression by means of an Fpr2-mediated reduced local and systemic inflammation. These results suggest this anti-inflammatory and pro-resolving agent has therapeutic potential for the treatment of atherosclerosis. © 2017 The British Pharmacological Society.

  3. Macrophage-specific expression of human apolipoprotein E reduces atherosclerosis in hypercholesterolemic apolipoprotein E-null mice.

    PubMed Central

    Bellosta, S; Mahley, R W; Sanan, D A; Murata, J; Newland, D L; Taylor, J M; Pitas, R E

    1995-01-01

    apoE deficiency causes hyperlipidemia and premature atherosclerosis. To determine if macrophage-specific expression of apoE would decrease the extent of atherosclerosis, we expressed human apoE in macrophages of apoE-null mice (apoE-/-) and assessed the effect on lipid accumulation in cells of the arterial wall. Macrophage-specific expression of human apoE in normal mice was obtained by use of the visna virus LTR. These animals were bred with apoE-/- mice to produce animals hemizygous for expression of human apoE in macrophages in the absence of murine apoE (apoE-/-,hTgE+/0). Low levels of human apoE mRNA were present in liver and spleen and high levels in lung and peritoneal macrophages. Human apoE was secreted by peritoneal macrophages and was detected in Kupffer cells of the liver. Human apoE in the plasma of apoE-/-,hTgE+/0 mice (n = 30) was inversely correlated (P < 0.005) with the plasma cholesterol concentration. After 15 wk on a normal chow diet, atherosclerosis was assessed in apoE-/-,hTgE+/0 animals and in apoE-/-,hTgE0/0 littermates matched for plasma cholesterol level (approximately 450 mg/dl) and lipoprotein profile. There was significantly less atherosclerosis in both the aortic sinus and in the proximal aorta (P < 0.0001) in the animals expressing the human apoE transgene. In apo-E-/-,hTgE+/0 animals, which had detectable atherosclerotic lesions, human apoE was detected in the secretory apparatus of macrophage-derived foam cells in the arterial wall. The data demonstrate that expression of apoE by macrophages is antiatherogenic even in the presence of high levels of atherogenic lipoproteins. The data suggest that apoE prevents atherosclerosis by promoting cholesterol efflux from cells of the arterial wall. Images PMID:7593602

  4. Docosahexaenoic acid prevents cognitive deficits in human apolipoprotein E epsilon 4-targeted replacement mice.

    PubMed

    Chouinard-Watkins, Raphaël; Vandal, Milène; Léveillé, Pauline; Pinçon, Anthony; Calon, Frédéric; Plourde, Mélanie

    2017-09-01

    At a population level, dietary consumption of fish rich in docosahexaenoic acid (DHA) is associated with prevention of cognitive decline but this association is not clear in carriers of the apolipoprotein E epsilon 4 allele (E4). Plasma and liver DHA concentrations show significant alterations in E4 carriers, in part corrected by DHA supplementation. However, whether DHA sufficiency in E4 carriers has consequences on cognition is unknown. Mice expressing human E4 or apolipoprotein E epsilon 3 allele (E3) were fed either a control diet or a diet containing DHA for 8 months and cognitive performance was tested using the object recognition test and the Barnes maze test. In E4 mice fed the control diet, impaired memory was detected and arachidonic acid concentrations were elevated in the hippocampus compared to E3 mice fed the control diet. DHA consumption prevented memory decline and restored arachidonic acid concentrations in the hippocampus of E4 mice. Our results suggest that long-term high-dose DHA intake may prevent cognitive decline in E4 carriers. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Dietary carnosine prevents early atherosclerotic lesion formation in apolipoprotein E-null mice.

    PubMed

    Barski, Oleg A; Xie, Zhengzhi; Baba, Shahid P; Sithu, Srinivas D; Agarwal, Abhinav; Cai, Jian; Bhatnagar, Aruni; Srivastava, Sanjay

    2013-06-01

    Atherosclerotic lesions are associated with the accumulation of reactive aldehydes derived from oxidized lipids. Although inhibition of aldehyde metabolism has been shown to exacerbate atherosclerosis and enhance the accumulation of aldehyde-modified proteins in atherosclerotic plaques, no therapeutic interventions have been devised to prevent aldehyde accumulation in atherosclerotic lesions. We examined the efficacy of carnosine, a naturally occurring β-alanyl-histidine dipeptide, in preventing aldehyde toxicity and atherogenesis in apolipoprotein E-null mice. In vitro, carnosine reacted rapidly with lipid peroxidation-derived unsaturated aldehydes. Gas chromatography mass-spectrometry analysis showed that carnosine inhibits the formation of free aldehydes 4-hydroxynonenal and malonaldialdehyde in Cu(2+)-oxidized low-density lipoprotein. Preloading bone marrow-derived macrophages with cell-permeable carnosine analogs reduced 4-hydroxynonenal-induced apoptosis. Oral supplementation with octyl-D-carnosine decreased atherosclerotic lesion formation in aortic valves of apolipoprotein E-null mice and attenuated the accumulation of protein-acrolein, protein-4-hydroxyhexenal, and protein-4-hydroxynonenal adducts in atherosclerotic lesions, whereas urinary excretion of aldehydes as carnosine conjugates was increased. The results of this study suggest that carnosine inhibits atherogenesis by facilitating aldehyde removal from atherosclerotic lesions. Endogenous levels of carnosine may be important determinants of atherosclerotic lesion formation, and treatment with carnosine or related peptides could be a useful therapy for the prevention or the treatment of atherosclerosis.

  6. Linoleic acid-rich fats reduce atherosclerosis development beyond its oxidative and inflammatory stress-increasing effect in apolipoprotein E-deficient mice in comparison with saturated fatty acid-rich fats.

    PubMed

    Sato, Masao; Shibata, Kenichi; Nomura, Run; Kawamoto, Daisuke; Nagamine, Rika; Imaizumi, Katsumi

    2005-12-01

    The relative benefit of replacing saturated fatty acid with linoleic acids is still being debated because a linoleic acid-enriched diet increases oxidative and inflammatory stresses, although it is associated with a reduction in serum cholesterol levels. The present study was conducted to evaluate the effect of dietary supplementation of linoleic acid-rich (HL) fat, compared with a saturated fatty acid-rich (SF) fat on atherosclerotic lesion areas, serum and liver cholesterol levels, oxidative stress (urinary isoprostanes and serum malondialdehayde) and inflammatory stress (expression of aortic monocyte chemoattractant protein-1; MCP-1) in apo E-deficient mice. Male and female apo E-deficient mice (8 weeks old; seven to eight per group) were fed an AIN-76-based diet containing SF fat (50 g palm oil and 50 g lard/kg) or HL fat (100 g high-linoleic safflower-seed oil/kg) for 9 weeks. Compared with the SF diet, the HL diet lowered atherosclerosis (P<0.05). It reduced serum total cholesterol levels (P<0.05), increased HDL-cholesterol levels (P<0.05) and lowered liver esterified cholesterol levels (P<0.01). The HL diet-fed mice showed increased expression of MCP-1 mRNA (P<0.05), serum levels of malondialdehayde (P<0.05) and urinary excretion of 2,3-dinor-5,6-dihydro-8-iso-prostaglandin F2alpha; P<0.05). These results suggest that having biomarkers in vivo for oxidative stress and inflammatory status of endothelial cells does not necessarily indicate predisposition to an increased lesion area in the aortic root in apo E-deficient mice fed an HL or SF diet.

  7. Bexarotene protects against traumatic brain injury in mice partially through apolipoprotein E.

    PubMed

    Zhong, Jianjun; Cheng, Chongjie; Liu, Han; Huang, Zhijian; Wu, Yue; Teng, Zhipeng; He, Junchi; Zhang, Hongrong; Wu, Jinchuan; Cao, Fang; Jiang, Li; Sun, Xiaochuan

    2017-02-20

    Bexarotene has been proved to have neuroprotective effects in many animal models of neurological diseases. However, its neuroprotection in traumatic brain injury (TBI) is still unknown. This study aims to explore the neuroprotective effects of bexarotene on TBI and its possible mechanism. Controlled cortical impact (CCI) model was used to simulate TBI in C57BL/6 mice as well as APOE gene knockout (APOE-KO) mice. After CCI, mice were daily dosed with bexarotene or vehicle solution intraperitoneally. The motor function, learning and memory, inflammatory factors, microglia amount, apoptosis condition around injury site and main side-effects were all measured. The results showed that, after CCI, bexarotene treatment markedly improved the motor function and spatial memory in C57BL/6 compare to APOE-KO mice which showed no improvement. The inflammatory cytokines, microglia amount, cell apoptosis rate, and protein of cleaved caspase-3 around the injury site were markedly upregulated after TBI in both C57BL/6 and APOE-KO mice, and all these upregulation were significantly mitigated by bexarotene treatment in C57BL/6 mice, but not in APOE-KO mice. No side-effects were detected after consecutive administration. Taken together, bexarotene inhibits the inflammatory response as well as cell apoptosis and improves the neurological function of mice after TBI partially through apolipoprotein E. This may make it a promising candidate for the therapeutic treatment after TBI.

  8. Increased sensitivity of apolipoprotein E knockout mice to copper-induced oxidative injury to the liver.

    PubMed

    Chen, Yuan; Li, Bin; Zhao, Ran-ran; Zhang, Hui-feng; Zhen, Chao; Guo, Li

    2015-04-10

    Apolipoprotein E (ApoE) genotypes are related to clinical presentations in patients with Wilson's disease, indicating that ApoE may play an important role in the disease. However, our understanding of the role of ApoE in Wilson's disease is limited. High copper concentration in Wilson's disease induces excessive generation of free oxygen radicals. Meanwhile, ApoE proteins possess antioxidant effects. We therefore determined whether copper-induced oxidative damage differ in the liver of wild-type and ApoE knockout (ApoE(-/-)) mice. Both wild-type and ApoE(-/-) mice were intragastrically administered with 0.2 mL of copper sulfate pentahydrate (200 mg/kg; a total dose of 4 mg/d) or the same volume of saline daily for 12 weeks, respectively. Copper and oxidative stress markers in the liver tissue and in the serum were assessed. Our results showed that, compared with the wild-type mice administered with copper, TBARS as a marker of lipid peroxidation, the expression of oxygenase-1 (HO-1), NAD(P)H dehydrogenase, and quinone 1 (NQO1) significantly increased in the ApoE(-/-) mice administered with copper, meanwhile superoxide dismutase (SOD) activity significantly decreased. Thus, it is concluded that ApoE may protect the liver from copper-induced oxidative damage in Wilson's disease.

  9. Aged Garlic Extract Suppresses the Development of Atherosclerosis in Apolipoprotein E-Knockout Mice.

    PubMed

    Morihara, Naoaki; Hino, Atsuko; Yamaguchi, Takako; Suzuki, Jun-Ichiro

    2016-02-01

    Aged garlic extract (AGE) has been shown to retard the progression of coronary calcification in patients with coronary artery disease. To clarify the mechanism of AGE's action to retard atherosclerosis, we investigated whether AGE suppresses the formation and progression of atherosclerosis in Apolipoprotein E (Apoe)-knockout (ApoE-KO) mice. Male C57BL/6J mice (control mice, 5 wk old) were fed a standard diet, whereas male ApoE-KO mice (5 wk old) were fed a standard diet with or without 3% AGE for 12 or 24 wk. After the treatment, blood samples, aortas, and spleens were collected from all mice. Concentrations of total cholesterol (TC), HDL cholesterol, and triglycerides (TGs) in serum were measured. The area of atherosclerotic lesion in the aorta was examined by Oil Red O staining. The relative abundances of monocytes plus macrophages (CD11b(+) cells) and interferon-γ-producing CD4(+) T cells in spleen were assessed by flow cytometric analysis. The atherosclerotic lesion areas in the aortas of ApoE-KO mice were 87 and 114 times as great (P < 0.01) as those in control mice at 12 and 24 wk, respectively. AGE feeding significantly inhibited the progression of atherosclerotic lesion area in ApoE-KO mice by 22% (P < 0.05) at 12 wk. In addition, serum concentrations of TC and TGs in ApoE-KO mice were significantly higher than those in control mice at 12 and 24 wk. Treatment with AGE significantly suppressed the increases in serum concentrations of TC and TGs in ApoE-KO mice by 21% (P < 0.05) and 19% (P < 0.05) at 24 wk, respectively, and reduced the relative abundance of CD11b(+) cells in ApoE-KO mice by 24% (P < 0.05) at 12 wk. These data suggest that the antiatherosclerotic activity of AGE is at least partly due to the suppression of inflammation and lipid deposition in the vessels during the early stage of atherosclerotic development in ApoE-KO mice. © 2016 American Society for Nutrition.

  10. Blue-Green Algae Inhibit the Development of Atherosclerotic Lesions in Apolipoprotein E Knockout Mice

    PubMed Central

    Ku, Chai Siah; Kim, Bohkyung; Pham, Tho X.; Yang, Yue; Wegner, Casey J.; Park, Young-Ki; Balunas, Marcy

    2015-01-01

    Abstract Hyperlipidemia and inflammation contribute to the development of atherosclerotic lesions. Our objective was to determine antiatherogenic effect of edible blue-green algae (BGA) species, that is, Nostoc commune var. sphaeroides Kützing (NO) and Spirulina platensis (SP), in apolipoprotein E knockout (ApoE−/−) mice, a well-established mouse model of atherosclerosis. Male ApoE−/− mice were fed a high-fat/high-cholesterol (HF/HC, 15% fat and 0.2% cholesterol by wt) control diet or a HF/HC diet supplemented with 5% (w/w) of NO or SP powder for 12 weeks. Plasma total cholesterol (TC) and triglycerides (TG) were measured, and livers were analyzed for histology and gene expression. Morphometric analysis for lesions and immunohistochemical analysis for CD68 were conducted in the aorta and the aortic root. NO supplementation significantly decreased plasma TC and TG, and liver TC, compared to control and SP groups. In the livers of NO-fed mice, less lipid droplets were present with a concomitant decrease in fatty acid synthase protein levels than the other groups. There was a significant increase in hepatic low-density lipoprotein receptor protein levels in SP-supplemented mice than in control and NO groups. Quantification of aortic lesions by en face analysis demonstrated that both NO and SP decreased aortic lesion development to a similar degree compared with control. While lesions in the aortic root were not significantly different between groups, the CD68-stained area in the aortic root was significantly lowered in BGA-fed mice than controls. In conclusion, both NO and SP supplementation decreased the development of atherosclerotic lesions, suggesting that they may be used as a natural product for atheroprotection. PMID:26566121

  11. Irisin protects against endothelial injury and ameliorates atherosclerosis in apolipoprotein E-Null diabetic mice.

    PubMed

    Lu, Junyan; Xiang, Guangda; Liu, Min; Mei, Wen; Xiang, Lin; Dong, Jing

    2015-12-01

    The circulating irisin increases energy expenditure and improves insulin resistance in mice and humans. The improvement of insulin resistance ameliorates atherosclerosis. Therefore, we hypothesized that irisin alleviates atherosclerosis in diabetes. Endothelial function was measured by acetylcholine-induced endothelium-dependent vasodilation using aortic rings in apolipoprotein E-Null (apoE(-/-)) streptozotocin-induced diabetic mice. Atherosclerotic lesion was evaluated by plaque area and inflammatory response in aortas. In addition, the endothelium-protective effects of irisin were also further investigated in primary human umbilical vein endothelial cells (HUVECs) in vitro. The in vivo experiments showed that irisin treatment significantly improved endothelial dysfunction, decreased endothelial apoptosis, and predominantly decreased atherosclerotic plaque area of both en face and cross sections when compared with normal saline-treated diabetic mice. Moreover, the infiltrating macrophages and T lymphocytes within plaque and the mRNA expression levels of inflammatory cytokines in aortas were also significantly reduced by irisin treatment in mice. The in vitro experiments revealed that irisin inhibited high glucose-induced apoptosis, oxidative stress and increased antioxidant enzymes expression in HUVECs, and pretreatment with LY294002, l-NAME, AMPK-siRNA or eNOS-siRNA, attenuated the protection of irisin on HUVECs apoptosis induced by high glucose. In addition, the in vivo and in vitro experiments showed that irisin increased the phosphorylation of AMPK, Akt and eNOS in aortas and cultured HUVECs. The present study indicates that systemic administration of irisin may be protected against endothelial injury and ameliorated atherosclerosis in apoE(-/-) diabetic mice. The endothelium-protective action of irisin was through activation of AMPK-PI3K-Akt-eNOS signaling pathway. Irisin could be therapeutic for atherosclerotic vascular diseases in diabetes. Copyright

  12. Blue-Green Algae Inhibit the Development of Atherosclerotic Lesions in Apolipoprotein E Knockout Mice.

    PubMed

    Ku, Chai Siah; Kim, Bohkyung; Pham, Tho X; Yang, Yue; Wegner, Casey J; Park, Young-Ki; Balunas, Marcy; Lee, Ji-Young

    2015-12-01

    Hyperlipidemia and inflammation contribute to the development of atherosclerotic lesions. Our objective was to determine antiatherogenic effect of edible blue-green algae (BGA) species, that is, Nostoc commune var. sphaeroides Kützing (NO) and Spirulina platensis (SP), in apolipoprotein E knockout (ApoE(-/-)) mice, a well-established mouse model of atherosclerosis. Male ApoE(-/-) mice were fed a high-fat/high-cholesterol (HF/HC, 15% fat and 0.2% cholesterol by wt) control diet or a HF/HC diet supplemented with 5% (w/w) of NO or SP powder for 12 weeks. Plasma total cholesterol (TC) and triglycerides (TG) were measured, and livers were analyzed for histology and gene expression. Morphometric analysis for lesions and immunohistochemical analysis for CD68 were conducted in the aorta and the aortic root. NO supplementation significantly decreased plasma TC and TG, and liver TC, compared to control and SP groups. In the livers of NO-fed mice, less lipid droplets were present with a concomitant decrease in fatty acid synthase protein levels than the other groups. There was a significant increase in hepatic low-density lipoprotein receptor protein levels in SP-supplemented mice than in control and NO groups. Quantification of aortic lesions by en face analysis demonstrated that both NO and SP decreased aortic lesion development to a similar degree compared with control. While lesions in the aortic root were not significantly different between groups, the CD68-stained area in the aortic root was significantly lowered in BGA-fed mice than controls. In conclusion, both NO and SP supplementation decreased the development of atherosclerotic lesions, suggesting that they may be used as a natural product for atheroprotection.

  13. Rosuvastatin reduces atherosclerotic lesions and promotes progenitor cell mobilisation and recruitment in apolipoprotein E knockout mice.

    PubMed

    Schroeter, Marco R; Humboldt, Tim; Schäfer, Katrin; Konstantinides, Stavros

    2009-07-01

    Statins enhance incorporation of bone marrow-derived cells into experimental neointimal lesions. However, the contribution of progenitor cells to progression of spontaneous atherosclerotic plaques, and the possible modulatory role of statins in this process, remain poorly understood. We compared the effects of rosuvastatin (1 and 10mg/kg BW) and pravastatin (10mg/kg) on progenitor cell mobilisation, recruitment into atherosclerotic plaques, and lesion growth. Statins were administered over 8 weeks to apolipoprotein E knockout mice on atherogenic diet. In addition, mice were lethally irradiated, followed by transplantation of bone marrow from LacZ transgenic mice. Rosuvastatin reduced lesion area and intima-to-media ratio at the brachiocephalic artery compared to vehicle, while both parameters were not significantly altered by pravastatin. Rosuvastatin also augmented endothelialisation (P<0.05) and reduced the smooth muscle cells (SMC) content (P=0.042) of lesions. Numbers of c-kit, sca-1 and flk-1, sca-1 double-positive progenitor cells were significantly increased in rosuvastatin compared to control-treated mice, both in the bone marrow and the peripheral blood. Similarly, the number of spleen-derived acLDL, lectin double-positive progenitor cells (P=0.001) and colony-forming units (P=0.0104) was significantly increased in mice treated with rosuvastatin compared to vehicle alone. In the bone marrow, increased Akt and p42/44 MAP kinase phosphorylation and upregulated SDF1alpha mRNA expression were observed. Importantly, rosuvastatin treatment also increased the plasma levels of c-kit ligand (P=0.003), and the number of c-kit-positive cells within atherosclerotic lesions (P=0.041). Our findings suggest that rosuvastatin reduces the size of atherosclerotic plaques, and this effect appears to involve progenitor cell mobilisation and recruitment into vascular lesions.

  14. Safrole-2',3'-oxide induces atherosclerotic plaque vulnerability in apolipoprotein E-knockout mice.

    PubMed

    Su, Le; Zhang, Haiyan; Zhao, Jing; Zhang, Shangli; Zhang, Yun; Zhao, Baoxiang; Miao, Junying

    2013-02-27

    Safrole-2',3'-oxide (SFO) is the major electrophilic metabolite of safrole (4-allyl-1, 2-methylenedioxybenzene), a natural plant constituent found in essential oils of numerous edible herbs and spices and in food containing these herbs, such as pesto sauce, cola beverages and bologna sausages. The effects of SFO in mammalian systems, especially the cardiovascular system, are little known. Disruption of vulnerable atherosclerotic plaques in atherosclerosis, a chronic inflammatory disease, is the main cause of cardiovascular events. In this study, we investigated SFO-induced atherosclerotic plaque vulnerability (possibility of rupture) in apolipoprotein E-knockout (apoE(-/-)) mice. Lipid area in vessel wall reached 59.8% in high dose SFO (SFO-HD) treated group, which is only 31.2% in control group. SFO treatment changed the lesion composition to an unstable phenotype, increased the number of apoptotic cells in plaque and the endothelium in plaques was damaged after SFO treatment. Furthermore, compared with control groups, the plaque endothelium level of p75(NTR) was 3-fold increased and the liver level of p75(NTR) was 17.4-fold increased by SFO-HD. Meanwhile, the serum level of KC (a functional homolog of IL-8 and the main proinflammatory alpha chemokine in mice) in apoE(-/-) mice was up to 357pg/ml in SFO-HD treated group. Thus, SFO contributes to the instability of atherosclerotic plaque in apoE(-/-) mice through activating p75(NTR) and IL-8 and cell apoptosis in plaque. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  15. Prenatal stress enhances severity of atherosclerosis in the adult apolipoprotein E-deficient mouse offspring via inflammatory pathways.

    PubMed

    Ho, H; Lhotak, S; Solano, M E; Karimi, K; Pincus, M K; Austin, R C; Arck, P

    2013-02-01

    Atherosclerosis is the underlying cause of cardiovascular disease and stroke. Endothelial cell dysfunctions are early events in atherosclerosis, resulting in the recruitment of circulating monocytes. The immune system can elicit an inflammatory response toward the atherosclerotic lesion, thereby accelerating lesion growth. Risk factors for atherosclerosis include hypertension, smoking, stress perception or low birth weight. As prenatal stress challenge decreases the birth weight and affects the offspring's postnatal immune response, we aimed to investigate whether prenatal stress contributes to the development of atherosclerosis in mice. Syngenic pregnant apolipoprotein E-deficient (apoE-/-) dams were exposed to sound stress on gestation days 12.5 and 14.5. The presence and size of atherosclerotic plaques in the offspring at the age of 15 weeks was evaluated by histomorphology, accompanied by flow cytometric analysis of the frequency and phenotype of monocytes/macrophages and regulatory T (Treg) cells in the blood. Further, cytokine secretion of peripheral blood lymphocytes was analyzed. In response to prenatal stress challenge, an increased frequency of large atherosclerotic plaques was detectable in apoE-/- offspring, which was particularly profound in females. Prenatal stress also resulted in alterations of the offspring's immune response, such as a decreased frequency of Treg cells in blood, alterations of macrophage populations in blood and an increased secretion of inflammatory cytokines. We provide novel evidence that prenatally stressed adult offspring show an increased severity of atherosclerosis. As Treg cells are key players in dampening inflammation, the observed increase in atherosclerosis may be due to the lack of Treg cell frequency. Future interdisciplinary research is urgently required to understand the developmental origin of prenatal stress-induced atherosclerosis. The availability of our model may facilitate and foster such research endeavors.

  16. Consumption of hydrogen water prevents atherosclerosis in apolipoprotein E knockout mice.

    PubMed

    Ohsawa, Ikuroh; Nishimaki, Kiyomi; Yamagata, Kumi; Ishikawa, Masahiro; Ohta, Shigeo

    2008-12-26

    Oxidative stress is implicated in atherogenesis; however most clinical trials with dietary antioxidants failed to show marked success in preventing atherosclerotic diseases. We have found that hydrogen (dihydrogen; H(2)) acts as an effective antioxidant to reduce oxidative stress [I. Ohsawa, M. Ishikawa, K. Takahashi, M. Watanabe, K. Nishimaki, K. Yamagata, K. Katsura, Y. Katayama, S, Asoh, S. Ohta, Hydrogen acts as a therapeutic antioxidant by selectively reducing cytotoxic oxygen radicals, Nat. Med. 13 (2007) 688-694]. Here, we investigated whether drinking H(2)-dissolved water at a saturated level (H(2)-water) ad libitum prevents arteriosclerosis using an apolipoprotein E knockout mouse (apoE(-/-)), a model of the spontaneous development of atherosclerosis. ApoE(-/-) mice drank H(2)-water ad libitum from 2 to 6 month old throughout the whole period. Atherosclerotic lesions were significantly reduced by ad libitum drinking of H(2)-water (p=0.0069) as judged by Oil-Red-O staining series of sections of aorta. The oxidative stress level of aorta was decreased. Accumulation of macrophages in atherosclerotic lesions was confirmed. Thus, consumption of H(2)-dissolved water has the potential to prevent arteriosclerosis.

  17. Soy protein inhibits inflammation-induced VCAM-1 and inflammatory cytokine induction by inhibiting the NF-kappaB and AKT signaling pathway in apolipoprotein E-deficient mice

    USDA-ARS?s Scientific Manuscript database

    Purpose: Inflammation is a hallmark of many diseases, such as atherosclerosis, autoimmune diseases, obesity, and cancer. Isoflavone-free soy protein diet (SPI(-)) has been shown to reduce atherosclerotic lesions in a hyperlipidemic mouse model compared to casein (CAS)-fed mice, despite unchanged ser...

  18. Scavenger receptor function of mouse Fcγ receptor III contributes to progression of atherosclerosis in apolipoprotein E hyperlipidemic mice.

    PubMed

    Zhu, Xinmei; Ng, Hang Pong; Lai, Yen-Chun; Craigo, Jodi K; Nagilla, Pruthvi S; Raghani, Pooja; Nagarajan, Shanmugam

    2014-09-01

    Recent studies showed loss of CD36 or scavenger receptor-AI/II (SR-A) does not ameliorate atherosclerosis in a hyperlipidemic mouse model, suggesting receptors other than CD36 and SR-A may also contribute to atherosclerosis. In this report, we show that apolipoprotein E (apoE)-CD16 double knockout (DKO; apoE-CD16 DKO) mice have reduced atherosclerotic lesions compared with apoE knockout mice. In vivo and in vitro foam cell analyses showed apoE-CD16 DKO macrophages accumulated less neutral lipids. Reduced foam cell formation in apoE-CD16 DKO mice is not due to change in expression of CD36, SR-A, and LOX-1. This led to a hypothesis that CD16 may have scavenger receptor activity. We presented evidence that a soluble form of recombinant mouse CD16 (sCD16) bound to malondialdehyde-modified low-density lipoprotein (MDALDL), and this binding is blocked by molar excess of MDA- modified BSA and anti-MDA mAbs, suggesting CD16 specifically recognizes MDA epitopes. Interestingly, sCD16 inhibited MDALDL binding to macrophage cell line, as well as soluble forms of recombinant mouse CD36, SR-A, and LOX-1, indicating CD16 can cross-block MDALDL binding to other scavenger receptors. Anti-CD16 mAb inhibited immune complex binding to sCD16, whereas it partially inhibited MDALDL binding to sCD16, suggesting MDALDL binding site may be in close proximity to the immune complex binding site in CD16. Loss of CD16 expression resulted in reduced levels of MDALDL-induced proinflammatory cytokine expression. Finally, CD16-deficient macrophages showed reduced MDALDL-induced Syk phosphorylation. Collectively, our findings suggest scavenger receptor activity of CD16 may, in part, contribute to the progression of atherosclerosis.

  19. [Impact of olmesartan medoxomil on atherosclerosis lesions in apolipoprotein E knockout mice].

    PubMed

    Li, H; Shi, L Y; Chen, L; Lu, Y Z; Yu, B; Qi, G X

    2016-08-16

    To investigate the effect and possible mechanisms of olmesartan medoxomil on atherosclerosis of apolipoprotein E knockout (ApoE(-/-)) mice. Sixteen 6-week-old male ApoE(-/-) mice were randomly divided into atherosclerosis model group fed with high fat diet, and olmesartan medoxomil intervention group fed with high fat diet and olmesartan medoxomil (10 mg·kg(-1)·day(-1,) per gavage). Eight C57BL/6 mice were fed with normal diet, and treated for 12 weeks.The blood pressure and the serum level of lipid were detected; the aorta were removed, oil red staining for plaque area, Hematoxylin and eosin (HE) staining for plaque morphology, Elastica van Gieson (EVG) staining for elastin, and picrosirius red (PSR) for collagen respectively; and the expression of cathepsin S (Cat S), smooth action protein (ASMA) and macrophage surface molecule-3 (Mac-3) were detected by immunohistochemisty analysis. Serum cholesterol and low density lipoprotein levels were significantly higher in atherosclerosis model group than in control group[(15.08±1.64) vs (2.06±0.15) mmol/L, (15.60±1.05) vs (0.00±0.00) mmol/L] (all P<0.01), while triglyceride level was similar between the two group.In contrast to model group, the mice in intervention group showed no statistical difference in blood pressure and plasma lipid levels, while the plaque areas in the aorta were significantly decreased (P<0.05) as well as the expression of Cat S and Mac-3[(2.4±1.2) vs (8.8±3.2)%, (2.2±1.2) vs (7.2±2.8)%] (all P<0.01). In addition, the elastin levels, collagen contents, and the expression of ASMA remained significantly higher compared with model group (P<0.05). Olmesartan medoxomil could slow down the atherosclerosis process, the possible mechanism was implicated with the suppression of Cat S and decreased inflammatory responses alongside the increased elastin and collagen contents.

  20. Icariin improves eNOS/NO pathway to prohibit the atherogenesis of apolipoprotein E-null mice.

    PubMed

    Xiao, Hong-Bo; Sui, Guo-Guang; Lu, Xiang-Yang

    2016-12-22

    Impaired endothelial nitric oxide synthase (eNOS)/nitric oxide (NO) pathway induces atherogenesis. The present study examined whether icariin improves the eNOS/NO pathway to prohibit the atherogenesis of apolipoprotein E-null (ApoE(-/-)) mice. In vitro, primary human umbilical vein endothelial cells (HUVECs) were randomly divided into 7 groups: control; vehicle; icariin 10; lyphosphatidylcholine (LPC) group; LPC + icariin 1; LPC + icariin 3; and LPC + icariin 10. In vivo, 80 mice were separated randomly into 4 groups (n = 20): control, ApoE(-/-), ApoE(-/-) + icariin 10, and ApoE(-/-) + icariin 30. ApoE(-/-) mice had significantly more atherosclerosis in the aortic root together with increased aortic ROS production, body mass, plasma triglyceride (TG) and total cholesterol (TC) concentration, decreased aortic eNOS expression, and plasma NO concentration. LPC (10 μg/mL) treatment induced a big decline in NO level in the conditioned medium and eNOS expression, and an increase in intracellular reactive oxygen species (ROS) production in HUVECs. Icariin treatment decreased atherogenesis, ROS production, body mass, plasma TG concentration, and plasma TC concentration, and increased NO concentration and eNOS expression. These findings suggested icariin could improve eNOS/NO-pathway to prohibit the atherogenesis of apolipoprotein E-null mice by restraining oxidative stress.

  1. Everolimus limits aortic aneurysm in the apolipoprotein E-deficient mouse by downregulating C-C chemokine receptor 2 positive monocytes.

    PubMed

    Moran, Corey S; Jose, Roby J; Moxon, Joseph V; Roomberg, Alicia; Norman, Paul E; Rush, Catherine; Körner, Heinrich; Golledge, Jonathan

    2013-04-01

    We aimed to determine the effect of mechanistic target of rapamycin inhibitor everolimus on abdominal aortic aneurysm within the angiotensin II (A2)-infused apolipoprotein E-deficient mouse model. Abdominal aortic aneurysm was induced via subcutaneous infusion of A2. Flow cytometry demonstrated increased circulating and aortic C-C chemokine receptor 2 (CCR2) monocytes during A2 infusion. The number of CCR2 monocytes present within the aorta was positively correlated with suprarenal aortic diameter. Simultaneous infusion of everolimus via a second subcutaneous osmotic micropump inhibited A2-induced aortic dilatation. Using flow cytometry and Western blot analysis, decreased aortic dilatation was associated with reduced development of CCR2 bone marrow monocytes, fewer numbers of circulating CCR2 monocytes, and lower aortic CCR2 concentration. In vitro, everolimus inhibited A2-stimulated production of interferon (IFN)-γ and IFNγ-induced CCR2 expression in apolipoprotein E-deficient mouse bone marrow monocytes. Further, everolimus diminished IFNγ/lipopolysaccharide-stimulated M1 polarization in apolipoprotein E-deficient mouse bone marrow monocyte-differentiated macrophages. Systemic administration of everolimus limits aortic aneurysm in the A2-infused apolipoprotein E-deficient mouse model via suppressed development of bone marrow CCR2 monocytes and reduced egress of these cells into the circulation.

  2. Differential effects of green tea-derived catechin on developing versus established atherosclerosis in apolipoprotein E-null mice.

    PubMed

    Chyu, Kuang-Yuh; Babbidge, Stephanie M; Zhao, Xiaoning; Dandillaya, Ram; Rietveld, Anton G; Yano, Juliana; Dimayuga, Paul; Cercek, Bojan; Shah, Prediman K

    2004-05-25

    Oxidative stress has been implicated in vascular injury and atherogenesis, and antioxidant treatment has shown favorable results in preclinical studies. Despite this, antioxidant therapy has failed to show benefit in clinical trials. Failure of antioxidants in clinical trials may be partly because such therapy is started after atherosclerosis is already well established, whereas the benefits in animal models may be results from early initiation of antioxidants while atherosclerosis is still evolving. To test this hypothesis, we evaluated the effect of epigallocatechin gallate (EGCG), the main antioxidant derived from green tea, on evolving and established atherosclerotic lesions in hypercholesterolemic apolipoprotein E-null mice. Established native aortic atherosclerotic lesions and evolving atherosclerotic lesions produced by periadventitial cuff injury to carotid arteries were assessed in mice after 21 and 42 days of treatment with daily intraperitoneal injections of EGCG (10 mg/kg) or PBS. EGCG treatment resulted in an increase in the antioxidant capacity in local vascular tissue and systemic circulation and reduced vascular smooth muscle cell proliferation and redox-sensitive gene activation in vitro. EGCG reduced cuff-induced evolving atherosclerotic plaque size at 21 and 42 days by 55% and 73%, respectively, compared with PBS treatment (P<0.05). Conversely, EGCG had no effect on established lesions in the aortic sinuses or the rest of the aorta. Our data suggest that antioxidant EGCG differentially reduces evolving atherosclerotic lesions without influencing established atherosclerosis in the apolipoprotein E-null mice.

  3. Generation of mice carrying a mutant apolipoprotein E gene inactivated by gene targeting in embryonic stem cells.

    PubMed Central

    Piedrahita, J A; Zhang, S H; Hagaman, J R; Oliver, P M; Maeda, N

    1992-01-01

    We have inactivated the endogenous apolipoprotein E (apoE) gene by using gene targeting in mouse embryonic stem (ES) cells. Two targeting plasmids were used, pJPB63 and pNMC109, both containing a neomycin-resistance gene that replaces a part of the apoE gene and disrupts its structure. ES cell colonies targeted after electroporation with plasmid pJPB63 were identified by the polymerase chain reaction (PCR) followed by genomic Southern analysis. Of 648 G418-resistant colonies analyzed, 9 gave a positive signal after PCR amplification, and 5 of them were confirmed as targeted by Southern blot analysis. The second plasmid, pNMC109, contains the negatively selectable thymidine kinase gene in addition to the neomycin-resistance gene. After electroporation with this plasmid, 177 colonies resistant both to G418 and ganciclovir were analyzed; 39 contained a disrupted apoE gene as determined by Southern blotting. Chimeric mice were generated by blastocyst injection with 6 of the targeted lines. One of the lines gave strong chimeras, three of which transmitted the disrupted apoE gene to their progeny. Mice homozygous for the disrupted gene were produced from the heterozygotes; they appear healthy, even though they have no apolipoprotein E in their plasma. Images PMID:1584779

  4. Apolipoprotein E-knockout mice on high-fat diet show autoimmune injury on kidney and aorta

    SciTech Connect

    Wang, Yuehai; Lu, Huixia; Huang, Ziyang; Lin, Huili; Lei, Zhenmin; Tang, Mengxiong; Gao, Fei; Dong, Mei; Li, Rongda; Lin, Ling

    2014-07-18

    Highlights: • Titers of ANA and anti-dsDNA antibodies were similar in ApoE{sup −/−} and Fas{sup −/−} mice. • The spleen weights and glomerular areas were similar in ApoE{sup −/−} and Fas{sup −/−} mice. • Expressions of IgG and C3 in glomeruli were similar in ApoE{sup −/−} and Fas{sup −/−} mice. • IgG, C3 and macrophage infiltration in aortic plaques were found in ApoE{sup −/−} mice. - Abstract: Background: Apolipoprotein E-knockout (ApoE{sup −/−}) mice is a classic model of atherosclerosis. We have found that ApoE{sup −/−} mice showed splenomegaly, higher titers of serum anti-nuclear antibody (ANA) and anti-dsDNA antibody compared with C57B6/L (B6) mice. However, whether ApoE{sup −/−} mice show autoimmune injury remains unclear. Methods and results: Six females and six males in each group, ApoE{sup −/−}, Fas{sup −/−} and B6 mice, were used in this study. The titers of serum ANA, anti-dsDNA antibody and creatinine and urine protein were measured by ELISA after 4 months of high-fat diet. The spleen weight and the glomerular area were determined. The expressions of IgG, C3 and macrophage in kidney and atherosclerotic plaque were detected by immunostaining followed by morphometric analysis. Similar to the characteristics of Fas{sup −/−} mice, a model of systemic lupus erythematosus (SLE), ApoE{sup −/−} mice, especially female, displayed significant increases of spleen weight and glomerular area when compared to B6 mice. Also, elevated titers of serum ANA, anti-dsDNA antibody and creatinine and urine protein. Moreover, the expressions of IgG, C3 and macrophage in glomeruli and aortic plaques were found in ApoE{sup −/−} mice. In addition, the IgG and C3 expressions in glomeruli and plaques significantly increased (or a trend of increase) in female ApoE{sup −/−} mice compared with males. Conclusions: Apolipoprotein E-knockout mice on high-fat diet show autoimmune injury on kidney and aorta.

  5. Obesity occurring in apolipoprotein E-knockout mice has mild effects on fertility.

    PubMed

    Zhang, Ting; Dai, Pengyuan; Cheng, Dong; Zhang, Liang; Chen, Zijiang; Meng, Xiaoqian; Zhang, Fumiao; Han, Xiaoying; Liu, Jianwei; Pan, Jie; Yang, Guiwen; Zhang, Cong

    2014-02-01

    The Apolipoprotein (Apo) family is implicated in lipid metabolism. There are five types of Apo: Apoa, Apob, Apoc, Apod, and Apoe. Apoe has been demonstrated to play a central role in lipoprotein metabolism and to be essential for efficient receptor-mediated plasma clearance of chylomicron remnants and VLDL remnant particles by the liver. Apoe-deficient (Apoe(-/-)) mice develop atherosclerotic plaques spontaneously, followed by obesity. In this study, we investigated whether lipid deposition caused by Apoe knockout affects reproduction in female mice. The results demonstrated that Apoe(-/-) mice were severely hypercholesterolemic, with their cholesterol metabolism disordered, and lipid accumulating in the ovaries causing the ovaries to be heavier compared with the WT counterparts. In addition, estrogen and progesterone decreased significantly at D 100. Quantitative PCR analysis demonstrated that at D 100 the expression of cytochromeP450 aromatase (Cyp19a1), 3β-hydroxysteroid dehydrogenase (Hsd3b), mechanistic target of rapamycin (Mtor), and nuclear factor-κB (Nfkb) decreased significantly, while that of BCL2-associated agonist of cell death (Bad) and tuberous sclerosis complex 2 (Tsc2) increased significantly in the Apoe(-/-) mice. However, there was no difference in the fertility rates of the Apoe(-/-) and WT mice; that is, obesity induced by Apoe knockout has no significant effect on reproduction. However, the deletion of Apoe increased the number of ovarian follicles and the ratio of ovarian follicle atresia and apoptosis. We believe that this work will augment our understanding of the role of Apoe in reproduction.

  6. Deletion of apolipoprotein E receptor-2 in mice lowers brain selenium and causes severe neurological dysfunction and death when a low-selenium diet is fed.

    PubMed

    Burk, Raymond F; Hill, Kristina E; Olson, Gary E; Weeber, Edwin J; Motley, Amy K; Winfrey, Virginia P; Austin, Lori M

    2007-06-06

    Selenoprotein P (Sepp1) is a plasma and extracellular protein that is rich in selenium. Deletion of Sepp1 results in sharp decreases of selenium levels in the brain and testis with dysfunction of those organs. Deletion of Sepp1 also causes increased urinary selenium excretion, leading to moderate depletion of whole-body selenium. The lipoprotein receptor apolipoprotein E receptor-2 (apoER2) binds Sepp1 and facilitates its uptake by Sertoli cells, thus providing selenium for spermatogenesis. Experiments were performed to assess the effect of apoER2 on the concentration and function of selenium in the brain and on whole-body selenium. ApoER2-/- and apoER2+/+ male mice were fed a semipurified diet with selenite added as the source of selenium. ApoER2-/- mice had depressed brain and testis selenium, but normal levels in liver, kidney, muscle, and the whole body. Feeding a selenium-deficient diet to apoER2-/- mice led to neurological dysfunction and death, with some of the characteristics exhibited by Sepp1-/- mice fed the same diet. Thus, although it does not affect whole-body selenium, apoER2 is necessary for maintenance of brain selenium and for prevention of neurological dysfunction and death under conditions of selenium deficiency, suggesting an interaction of apoER2 with Sepp1 in the brain.

  7. Human apolipoprotein E ɛ4 expression impairs cerebral vascularization and blood–brain barrier function in mice

    PubMed Central

    Alata, Wael; Ye, Yue; St-Amour, Isabelle; Vandal, Milène; Calon, Frédéric

    2015-01-01

    Human apolipoprotein E (APOE) exists in three isoforms ɛ2, ɛ3, and ɛ4, of which APOE4 is the main genetic risk factor of Alzheimer's disease (AD). As cerebrovascular defects are associated with AD, we tested whether APOE genotype has an impact on the integrity and function of the blood–brain barrier (BBB) in human APOE-targeted replacement mice. Using the quantitative in situ brain perfusion technique, we first found lower (13.0% and 17.0%) brain transport coefficient (Clup) of [3H]-diazepam in APOE4 mice at 4 and 12 months, compared with APOE2 and APOE3 mice, reflecting a decrease in cerebral vascularization. Accordingly, results from immunohistofluorescence experiments revealed a structurally reduced cerebral vascularization (26% and 38%) and thinner basement membranes (30% and 35%) in 12-month-old APOE4 mice compared with APOE2 and APOE3 mice, suggesting vascular atrophy. In addition, APOE4 mice displayed a 29% reduction in [3H]-d-glucose transport through the BBB compared with APOE2 mice without significant changes in the expression of its transporter GLUT1 in brain capillaries. However, an increase of 41.3% of receptor for advanced glycation end products (RAGE) was found in brain capillaries of 12-month-old APOE4 mice. In conclusion, profound divergences were observed between APOE genotypes at the cerebrovascular interface, suggesting that APOE4-induced BBB anomalies may contribute to AD development. PMID:25335802

  8. Xanthohumol Prevents Atherosclerosis by Reducing Arterial Cholesterol Content via CETP and Apolipoprotein E in CETP-Transgenic Mice

    PubMed Central

    Segawa, Shuichi; Ozaki, Moeko; Kobayashi, Naoyuki; Shigyo, Tatsuro; Chiba, Hitoshi

    2012-01-01

    Background Xanthohumol is expected to be a potent anti-atherosclerotic agent due to its inhibition of cholesteryl ester transfer protein (CETP). In this study, we hypothesized that xanthohumol prevents atherosclerosis in vivo and used CETP-transgenic mice (CETP-Tg mice) to evaluate xanthohumol as a functional agent. Methodology/Principal Findings Two strains of mice, CETP-Tg and C57BL/6N (wild-type), were fed a high cholesterol diet with or without 0.05% (w/w) xanthohumol ad libitum for 18 weeks. In CETP-Tg mice, xanthohumol significantly decreased accumulated cholesterol in the aortic arch and increased HDL cholesterol (HDL-C) when compared to the control group (without xanthohumol). Xanthohumol had no significant effect in wild-type mice. CETP activity was significantly decreased after xanthohumol addition in CETP-Tg mice compared with the control group and it inversely correlated with HDL-C (%) (P<0.05). Furthermore, apolipoprotein E (apoE) was enriched in serum and the HDL-fraction in CETP-Tg mice after xanthohumol addition, suggesting that xanthohumol ameliorates reverse cholesterol transport via apoE-rich HDL resulting from CETP inhibition. Conclusions Our results suggest xanthohumol prevents cholesterol accumulation in atherogenic regions by HDL-C metabolism via CETP inhibition leading to apoE enhancement. PMID:23166663

  9. The Akt-nitric oxide-cGMP pathway contributes to nerve growth factor-mediated neurite outgrowth in apolipoprotein E knockout mice.

    PubMed

    Hashikawa-Hobara, Narumi; Hashikawa, Naoya; Yutani, Chikao; Zamami, Yoshito; Jin, Xin; Takatori, Shingo; Mio, Mitsunobu; Kawasaki, Hiromu

    2011-08-01

    Apolipoprotein E (apo)-deficient [apoE(-/-)] mice have peripheral sensory nerve defects and a reduced and delayed response to noxious thermal stimuli. However, to date, no report has focused on the influence of apoE deficiency on calcitonin gene-related peptide (CGRP)-containing nerve fiber extensions. We have shown that the density of CGRP-containing nerve fibers decreases in mesenteric arteries of apoE(-/-) mice compared with wild-type mice. Here, we investigated whether apoE deficiency is involved in nerve growth factor (NGF)-induced CGRP-containing nerve regeneration using apoE(-/-) mice. NGF-mediated CGRP-like immunoreactivity (LI)-neurite outgrowth in apoE(-/-) cultured dorsal root ganglia (DRG) cells was significantly lower than that in wild-type cultures. However, the level of NGF receptor mRNA in apoE(-/-) DRG cells was similar to that in wild-type mice. To clarify the mechanism of the impaired ability of NGF-mediated neurite outgrowth, we focused on the Akt-nitric oxide (NO)-cGMP pathway. Expression of phosphorylated Akt was significantly reduced in apoE(-/-) DRG. The NO donor, sodium nitroprusside or S-nitroso-N-acetylpenicillamine, did not affect NGF-mediated neurite outgrowth in apoE(-/-) cultured DRG cells. However, 8-bromoguanosine 3',5'-cyclic monophosphate sodium salt n-hydrate, a cGMP analog, induced NGF-mediated nerve facilitation similar to wild-type NGF-mediated neurite outgrowth levels. Furthermore, in apoE(-/-) DRG, soluble guanylate cyclase expression was significantly lower than that in wild-type DRG. These results suggest that in apoE(-/-) mice the Akt-NO-cGMP pathway is impaired, which may be caused by NGF-mediated CGRP-LI-neurite outgrowth defects.

  10. Effect of tocopherol on atherosclerosis, vascular function, and inflammation in apolipoprotein E knockout mice with subtotal nephrectomy.

    PubMed

    Shing, Cecilia M; Fassett, Robert G; Peake, Jonathan M; Coombes, Jeff S

    2014-12-01

    Inflammation and endothelial dysfunction contribute to cardiovascular disease, prevalent in chronic kidney disease (CKD). Antioxidant supplements such as tocopherols may reduce inflammation and atherosclerosis. This study aimed to investigate the effect of tocopherol supplementation on vascular function, aortic plaque formation, and inflammation in apolipoprotein E(-/-) mice with 5/6 nephrectomy as a model of combined cardiovascular and kidney disease. Nephrectomized mice were assigned to a normal chow diet group (normal chow), a group receiving 1000 mg/kg diet of α-tocopherol supplementation or a group receiving 1000 mg/kg diet mixed-tocopherol (60% γ-tocopherol). Following 12 weeks, in vitro aortic endothelial-independent relaxation was enhanced with both α-tocopherol and mixed-tocopherol (P < 0.05), while mixed-tocopherol enhanced aortic contraction at noradrenaline concentrations of 3 × 10(-7) M to 3 × 10(-5) M (P < 0.05), when compared to normal chow. Supplementation with α- and mixed-tocopherol reduced systemic concentrations of IL-6 (P < 0.001 and P < 0.001, respectively) and IL-10 (P < 0.05 and P < 0.001, respectively), while α-tocopherol also reduced MCP-1 (P < 0.05) and tumor necrosis factor (TNF)-α (P < 0.05). Aortic sinus plaque area was significantly reduced with α-tocopherol supplementation when compared to normal chow (P < 0.01). Tocopherol supplementation favorably influenced vascular function and cytokine profile, while it was also effective in reducing atherosclerosis in the apolipoprotein E(-/-) mouse with CKD. © 2014 John Wiley & Sons Ltd.

  11. Ultrasound Biomicroscopic Imaging for Interleukin-1 Receptor Antagonist-Inhibiting Atherosclerosis and Markers of Inflammation in Atherosclerotic Development in Apolipoprotein-E Knockout Mice.

    PubMed

    Li, Rong-Juan; Sun, Yan; Wang, Qin; Yang, Jiao; Yang, Ya; Song, Li; Wang, Zheng; Luo, Xiang-Hong; Su, Rui-Juan

    2015-08-01

    We sought to validate the hypothesis that the development of atherosclerosis can be suppressed by the interleukin-1 receptor antagonist (IL-1Ra) in murine models of atherosclerosis in vivo, noninvasively seen by means of high-resolution ultrasound biomicroscopy, and we studied changes in inflammatory markers such as IL-1 and C-reactive protein (CRP) plasma levels in these models of atherosclerosis. We divided IL-1Ra(+/-)/apolipoprotein-E (apoE)(-/-) and IL-1Ra(+/+)/apoE(-/-) mice into 2 age groups, used as atherosclerotic models. The control groups were age-matched IL-1Ra(+/+)/apoE(+/+) mice. Plaque thickness was measured in the ascending aorta in short-axis images by means of ultrasound and histology. Plasma levels of IL-1 and CRP were quantified in the 3 murine groups. At 16 weeks, plaque thickness in the ascending aortas of the IL-1Ra(+/-)/apoE(-/-) mice was significantly greater than that in the IL-1Ra(+/+)/apoE(-/-) mice, on ultrasound and histology (P <0.01). In contrast, at 32 weeks, the differences between these 2 genotypes were not statistically significant. Serum IL-1 levels were lower in the IL-1Ra(+/-)/apoE(-/-) mice than in the IL-1Ra(+/+)/apoE(-/-) mice at 16 and 32 weeks (P <0.05). At 16 weeks, serum CRP levels in the IL-1Ra(+/-)/apoE(-/-) mice were higher than in the IL-1Ra(+/+)/apoE(-/-) mice (P <0.01). Our results suggest that ultrasound biomicroscopy enables evaluation of atherosclerotic lesions in vivo, noninvasively and in real-time, in apoE(-/-) mice. Partial IL-1Ra deficiencies might promote early plaque development in 16-week-old apoE(-/-) mice. The balance of IL-1 and IL-1Ra might influence atherosclerotic development. Finally, CRP might affect the initiation of atherosclerosis, rather than its progression.

  12. Live Observation of Atherosclerotic Plaque Disruption in Apolipoprotein E-Deficient Mouse

    PubMed Central

    Daeichin, V.; Sluimer, J. C.; van der Heiden, K.; Skachkov, I.; Kooiman, K.; Janssen, A.; Janssen, B.; Bosch, J. G.; de Jong, N.; Daemen, M. J. A. P.; van der Steen, A. F. W.

    2015-01-01

    Aim: The actual occurrence of spontaneous plaque rupture in mice has been a matter of debate. We report on an in vivo observation of the actual event of possible plaque disruption in a living ApoE-/- mouse. Methods and Results: During live contrast-enhanced ultrasonography of a 50-week-old ApoE-/- male mouse, symptoms suggesting plaque disruption in the brachiocephalic artery were observed. Histological analysis confirmed the presence of advanced atherosclerotic lesions with dissections and intraplaque hemorrhage in the affected brachiocephalic trunk, pointing towards plaque rupture as the cause of the observed event. However, we did not detect a luminal thrombus or cap rupture, which is a key criterion for plaque rupture in human atherosclerosis. Conclusion: This study reports the real-time occurrence of a possible plaque rupture in a living ApoE-/- mouse. PMID:27689156

  13. Lactobacillus acidophilus ATCC 4356 Prevents Atherosclerosis via Inhibition of Intestinal Cholesterol Absorption in Apolipoprotein E-Knockout Mice

    PubMed Central

    Wang, Jinfeng; Quan, Guihua; Wang, Xiaojun; Yang, Longfei; Zhong, Lili

    2014-01-01

    The objective of this study was to investigate the effect of Lactobacillus acidophilus ATCC 4356 on the development of atherosclerosis in apolipoprotein E-knockout (ApoE−/−) mice. Eight-week-old ApoE−/− mice were fed a Western diet with or without L. acidophilus ATCC 4356 daily for 16 weeks. L. acidophilus ATCC 4356 protected ApoE−/− mice from atherosclerosis by reducing their plasma cholesterol levels from 923 ± 44 to 581 ± 18 mg/dl, likely via a marked decrease in cholesterol absorption caused by modulation of Niemann-Pick C1-like 1 (NPC1L1). In addition, suppression of cholesterol absorption induced reverse cholesterol transport (RCT) in macrophages through the peroxisome proliferator-activated receptor/liver X receptor (PPAR/LXR) pathway. Fecal lactobacillus and bifidobacterium counts were significantly (P < 0.05) higher in the L. acidophilus ATCC 4356 treatment groups than in the control groups. Furthermore, L. acidophilus ATCC 4356 was detected in the rat small intestine, colon, and feces during the feeding trial. The bacterial levels remained high even after the administration of lactic acid bacteria had been stopped for 2 weeks. These results suggest that administration of L. acidophilus ATCC 4356 can protect against atherosclerosis through the inhibition of intestinal cholesterol absorption. Therefore, L. acidophilus ATCC 4356 may be a potential therapeutic material for preventing the progression of atherosclerosis. PMID:25261526

  14. Lactobacillus acidophilus ATCC 4356 prevents atherosclerosis via inhibition of intestinal cholesterol absorption in apolipoprotein E-knockout mice.

    PubMed

    Huang, Ying; Wang, Jinfeng; Quan, Guihua; Wang, Xiaojun; Yang, Longfei; Zhong, Lili

    2014-12-01

    The objective of this study was to investigate the effect of Lactobacillus acidophilus ATCC 4356 on the development of atherosclerosis in apolipoprotein E-knockout (ApoE(-/-)) mice. Eight-week-old ApoE(-/-) mice were fed a Western diet with or without L. acidophilus ATCC 4356 daily for 16 weeks. L. acidophilus ATCC 4356 protected ApoE(-/-) mice from atherosclerosis by reducing their plasma cholesterol levels from 923 ± 44 to 581 ± 18 mg/dl, likely via a marked decrease in cholesterol absorption caused by modulation of Niemann-Pick C1-like 1 (NPC1L1). In addition, suppression of cholesterol absorption induced reverse cholesterol transport (RCT) in macrophages through the peroxisome proliferator-activated receptor/liver X receptor (PPAR/LXR) pathway. Fecal lactobacillus and bifidobacterium counts were significantly (P < 0.05) higher in the L. acidophilus ATCC 4356 treatment groups than in the control groups. Furthermore, L. acidophilus ATCC 4356 was detected in the rat small intestine, colon, and feces during the feeding trial. The bacterial levels remained high even after the administration of lactic acid bacteria had been stopped for 2 weeks. These results suggest that administration of L. acidophilus ATCC 4356 can protect against atherosclerosis through the inhibition of intestinal cholesterol absorption. Therefore, L. acidophilus ATCC 4356 may be a potential therapeutic material for preventing the progression of atherosclerosis. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  15. Aronia melanocarpa (chokeberry) polyphenol-rich extract improves antioxidant function and reduces total plasma cholesterol in apolipoprotein E knockout mice.

    PubMed

    Kim, Bohkyung; Ku, Chai Siah; Pham, Tho X; Park, Youngki; Martin, Derek A; Xie, Liyang; Taheri, Rod; Lee, Jiyoung; Bolling, Bradley W

    2013-05-01

    We hypothesized that a polyphenol-rich chokeberry extract (CBE) would modulate hepatic lipid metabolism and improve antioxidant function in apolipoprotein E knockout (apoE(-/-)) mice. ApoE(-/-) mice were fed diets containing 15% fat with 0.2% cholesterol alone or supplemented with 0.005% or 0.05% CBE for 4 weeks. CBE polyphenol content was determined by the total phenols, 4-dimethylaminocinnamaldehyde, and ultra high-performance liquid chromatography-mass spectrometry methods. The 0.05% CBE diet provided mice with mean daily doses of 1.2 mg gallic acid equivalents of total phenols, 0.19 mg anthocyanins, 0.17 mg phenolic acids, 0.06 mg proanthocyanidins (as catechin-equivalents), and 0.02 mg flavonols. The 0.05% CBE group had 12% less plasma total cholesterol concentrations than the control. Despite the hypocholesterolemic effect of CBE, hepatic mRNA levels of low-density lipoprotein receptor, hydroxyl-3-methylglutaryl coenzyme A reductase and cholesterol 7α-hydroxylase in CBE-fed mice were not significantly different from controls. Dietary CBE did not alter hepatic lipid content or the hepatic expression of genes involved in lipogenesis and fatty acid β-oxidation such as fatty acid synthase, carnitine palmitoyltransferase 1 and acyl-CoA oxidase. Plasma paraoxonase and catalase activities were significantly increased in mice fed 0.05% CBE. Both CBE diets increased hepatic glutathione peroxidase (GPx) activity but the 0.05% CBE group had 24% less proximal intestine GPx activity relative to controls. Thus, dietary CBE lowered total cholesterol and improved plasma and hepatic antioxidant function at nutritionally-relevant doses in apoE(-/-) mice. Furthermore, the CBE cholesterol-lowering mechanism in apoE(-/-) mice was independent of hepatic expression of genes involved in cholesterol metabolism.

  16. Amyloid-β42 Alters Apolipoprotein E Solubility in Brains of Mice with Five Familial AD Mutations

    PubMed Central

    Youmans, Katherine Lynn; Leung, Steffi; Zhang, Juan; Maus, Erika; Baysac, Kathleen; Bu, Guojun; Vassar, Robert; Yu, Chunjiang; LaDu, Mary Jo

    2011-01-01

    Amyloid plaques composed of the 42 amino acid form of amyloid-beta peptide (Aβ42) are a pathological hallmark of Alzheimer’s disease (AD), but soluble and intraneuronal Aβ42 are the more proximal causes of synaptic dysfunction and neurotoxicity. Apolipoprotein E (apoE) modulates this disease process, as inheritance of the ε4 allele of the apoE gene is the primary genetic risk factor for AD. To address the solubility of Aβ42 and apoE, a protein extraction protocol in the presence of minimal to extensive Aβ42 pathology was optimized. Sequential extractions with TBS, TBS+Triton X-100 (TBSX), and guanidine-HCl (GuHCl) or formic acid (FA) were used with tissue from young and old wild type or mice expressing 5 familial AD mutations (5xFAD), in disease-susceptible or –resistant brain regions. In older 5xFAD mice, the extraction of insoluble Aβ42 and m-apoE protein was increased with FA compared to GuHCl. The 5 FAD mutations significantly increase production of Aβ42, recapitulating AD-like pathology at a greatly accelerated rate. Consistent protein extraction and the specificity of extractions for soluble or membrane-associated proteins were demonstrated. Age-dependent increases in Aβ42 were observed in all extraction fractions, particularly in the cortex and hippocampus. In both young and old 5xFAD mice, Aβ42 is TBS- or GuHCl-soluble. While in WT mice m-apoE is TBSX-soluble, in 5xFAD mice m-apoE is TBS- or GuHCl-soluble. Thus, the extraction profile of Aβ42 paralleled that of m-apoE in 5xFAD mice. As now characterized, this method identifies the extraction profile for disease-relevant brain proteins, both normal or modified due to neuropathological processes. PMID:21219931

  17. Apolipoprotein E-knockout mice show increased titers of serum anti-nuclear and anti-dsDNA antibodies

    SciTech Connect

    Wang, Yuehai; Huang, Ziyang; Lu, Huixia; Lin, Huili; Wang, Zhenhua; Chen, Xiaoqing; Ouyang, Qiufang; Tang, Mengxiong; Hao, Panpan; Ni, Jingqin; Xu, Dongming; Zhang, Mingxiang; Zhang, Qunye; Lin, Ling; and others

    2012-07-13

    Highlights: Black-Right-Pointing-Pointer Titers of ANA and anti-dsDNA antibodies were higher in ApoE{sup -/-} than C57B6/L mice. Black-Right-Pointing-Pointer Spleen was greater and splenocyte apoptosis lower in ApoE{sup -/-} than B6 mice. Black-Right-Pointing-Pointer Level of TLR4 was lower in spleen tissue of ApoE{sup -/-} than B6 mice. Black-Right-Pointing-Pointer The TLR4 pathway may participate in maintaining the balance of splenocyte apoptosis. Black-Right-Pointing-Pointer The TLR4 pathway may participate in antibody production in spleen tissue. -- Abstract: Apolipoprotein E-knockout (ApoE{sup -/-}) mice, atherosclerosis-prone mice, show an autoimmune response, but the pathogenesis is not fully understood. We investigated the pathogenesis in female and male ApoE{sup -/-} mice. The spleens of all ApoE{sup -/-} and C57BL/6 (B6) mice were weighed. The serum IgG level and titers of anti-nuclear antibody (ANA) and anti-double-stranded DNA (anti-dsDNA) antibody were assayed by ELISA. Apoptosis of spleen tissue was evaluated by TUNEL. TLR4 level in spleen tissue was tested by immunohistochemistry and Western blot analysis. Levels of MyD88, p38, phosphorylated p38 (pp38), interferon regulatory factor 3 (IRF3) and Bcl-2-associated X protein (Bax) in spleen tissue were detected by Western blot analysis. We also survey the changes of serum autoantibodies, spleen weight, splenocyte apoptosis and the expressions of TLR4, MyD88, pp38, IRF3 and Bax in spleen tissue in male ApoE{sup -/-} mice after 4 weeks of lipopolysaccharide (LPS), Toll-like receptor 4 ligand, administration. ApoE{sup -/-} mice showed splenomegaly and significantly increased serum level of IgG and titers of ANA and anti-dsDNA antibody as compared with B6 mice. Splenocyte apoptosis and the expression of TLR4, MyD88, pp38, IRF3 and Bax in spleen tissue were significantly lower in ApoE{sup -/-} than B6 mice. The expression of TLR4, MyD88, IRF3, pp38, and Bax differed by sex in ApoE{sup -/-} spleen tissue. The

  18. Apolipoprotein E isoform-dependent effects on anxiety and cognition in female TR mice

    PubMed Central

    Siegel, Jessica A.; Haley, Gwendolen E.; Raber, Jacob

    2010-01-01

    Compared with apoE3, apoE4 is associated with increased risk to develop age-related cognitive decline, particularly in women. In this study, young, middle-aged, and old female mice expressing human apoE under control of the mouse apoE promoter were behaviorally analyzed. Cognitive performance in the water maze decreased with age in all mice. Compared with apoE2 and apoE3 mice, apoE4 mice showed better cognitive performance and higher measures of anxiety than apoE2 and apoE3 mice. Measures of anxiety correlated with cognitive performance in the water maze and passive avoidance tests and might have contributed to the enhanced cognitive performance of the apoE4 mice. ApoE4 mice showed better water maze learning and higher cortical apoE levels than mice expressing apoE4 in astrocytes under control of the GFAP promoter. This was not seen in apoE3 mice. There were no line differences in either genotype in spatial memory retention in the probe trial following the last day of hidden platform training. Thus, the promoter used to express apoE4 critically modulates its effects on brain function. PMID:20400205

  19. Impact of the apolipoprotein E polymorphism, age and sex on neurogenesis in mice: pathophysiological relevance for Alzheimer's disease?

    PubMed

    Koutseff, Alexis; Mittelhaeuser, Christophe; Essabri, Karim; Auwerx, Johan; Meziane, Hamid

    2014-01-13

    Apolipoprotein E (ApoE) is found in three different forms in humans (ApoE2, ApoE3 and ApoE4), and ApoE polymorphism is recognized as a major risk factor for Alzheimer's disease (AD). ApoE is involved in lipid and cholesterol transport, cell repair, and amyloid-β deposition and certain studies suggest potential implications in neurogenesis. In this regard, we investigated the possible impact of the three different human ApoE isoforms on neurogenesis. We used ApoE knock-in mice of different ages and sex, and quantified newborn cells in the hippocampus by flow cytometry. Young adult ApoE4 mice (10-12 week-old) from both sexes displayed reduced neurogenesis compared with wild-types and the other genotypes. In addition, young adult ApoE2 female mice showed improved hippocampal progenitor cell proliferation. In older mice (1 year), hippocampal neurogenesis was globally decreased, particularly in females, and the difference between ApoE4 and the other genotypes observed in young animals disappeared for the two sexes, except for aged ApoE3 females. Indeed, a surprising protective effect of the ApoE3 genotype was observed in aged females. Our study highlights the role of ApoE in neurogenesis, and shows for the first time an early inequality between the ApoE genotypes. The reduced neurogenesis observed for the ApoE4 genotype and the improved results obtained in young ApoE2 females support the idea of a difference in the balance between neuronal birth and death modulated by the ApoE polymorphism in young animals. The maintenance of this balance and its modulation can influence pathophysiological mechanisms predisposing to neurodegenerative diseases like AD. © 2013 Elsevier B.V. All rights reserved.

  20. Cholesterol lowering in low density lipoprotein receptor knockout mice overexpressing apolipoprotein E.

    PubMed Central

    Osuga, J; Yonemoto, M; Yamada, N; Shimano, H; Yagyu, H; Ohashi, K; Harada, K; Kamei, T; Yazaki, Y; Ishibashi, S

    1998-01-01

    Apo E is a key molecule in the lipoprotein metabolism; thus, genetic manipulation of apo E may prove useful in the treatment of hypercholesterolemia. To test the feasibility of this idea, we have generated low density lipoprotein receptor (LDLR) knockout mice that overexpress the rat apo E transgene (ETg+/+:LDLRKO), and compared their plasma lipoprotein profiles with those of nonexpressing LDLR knockout mice (ETg-/-:LDLRKO). On a normal chow diet, the mean plasma cholesterol level of ETg+/+:LDLRKO mice was significantly lower than that of ETg-/-:LDLRKO mice (189 versus 240 mg/dl, P < 0. 01). The LDL fraction was selectively reduced in the ETg+/+:LDLRKO mice. Despite the challenge with an atherogenic diet, cholesterol lowering was persistently observed and fatty streak lesions in the aortic sinus were significantly suppressed in the mice overexpressing apo E. These results imply that stimulation of hepatic production of apo E may be used as a promising adjunctive therapy for homozygous familial hypercholesterolemia. PMID:9664080

  1. GABAergic Interneuron Dysfunction Impairs Hippocampal Neurogenesis in Adult Apolipoprotein E4 Knock-in Mice

    PubMed Central

    Li, Gang; Bien-Ly, Nga; Andrews-Zwilling, Yaisa; Xu, Qin; Bernardo, Aubrey; Ring, Karen; Halabisky, Brian; Deng, Changhui; Mahley, Robert W.; Huang, Yadong

    2010-01-01

    SUMMARY Apolipoprotein (apo) E has important and diverse functions in neurobiology, and apoE4 is the major known genetic risk factor for Alzheimer’s disease. Here we report that adult neural stem/progenitor cells (NSCs) express apoE. In apoE knockout mice, neurogenesis in the hippocampus was ~60% lower than in wildtype mice, and most newborn cells developed into astrocytes rather than into neurons as in wildtype mice. This impairment was not observed in human apoE3 knock-in mice. In apoE4 knock-in mice, however, the maturation and dendritic development of newborn hippocampal neurons was significantly impaired as a result of apoE4 and its fragment-caused GABAergic interneuron dysfunction. This impairment was fully rescued by treatment with a GABAA receptor potentiator. These findings demonstrate the importance of apoE in adult hippocampal neurogenesis and show that apoE4 inhibits hippocampal neurogenesis by impairing neuronal maturation mediated by GABA signaling. PMID:19951691

  2. Atorvastatin Upregulates the Expression of miR-126 in Apolipoprotein E-knockout Mice with Carotid Atherosclerotic Plaque.

    PubMed

    Pan, Xudong; Hou, Rongyao; Ma, Aijun; Wang, Ting; Wu, Mei; Zhu, Xiaoyan; Yang, Shaonan; Xiao, Xing

    2017-01-01

    Carotid atherosclerosis (AS) is a chronic inflammatory disease of the carotid arterial wall, which is very important in terms of the occurrence of cerebral vascular accidents. Studies have demonstrated that microRNAs (miRNAs) and their target genes are involved in the formation of atherosclerosis and that atorvastatin might reduce atherosclerotic plaques by regulating the expression of miRNAs. However, the related mechanism is not yet known. In this study, we first investigated the effects of atorvastatin on miR-126 and its target gene, i.e., vascular cell adhesion molecule-1 (VCAM-1) in apolipoprotein E-knockout (ApoE-/-) mice with carotid atherosclerotic plaque in vivo. We compared the expressions of miR-126 and VCAM-1 between the control, atherosclerotic model and atorvastatin treatment groups of ApoE-/- mice using RT-PCR and Western blot. We found the miR-126 expression was significantly down-regulated, and the VCAM-1 expression was significantly up-regulated in the atherosclerotic model group, which accelerated the progression of atherosclerosis in the ApoE-/- mice. These results following atorvastatin treatment indicated that miR-126 expression was significantly up-regulated, VCAM-1 expression was significantly down-regulated and atherosclerotic lesions were reduced. The present results might explain the mechanism by which miR-126 is involved in the formation of atherosclerosis in vivo. Our study first indicated that atorvastatin might exert its anti-inflammatory effects in atherosclerosis by regulating the expressions of miR-126 and VCAM-1 in vivo.

  3. Apolipoprotein E4 domain interaction accelerates diet-induced atherosclerosis in hypomorphic Arg-61 Apoe mice

    PubMed Central

    Eberlé, Delphine; Kim, Roy Y.; Luk, Fu Sang; de Mochel, Nabora Soledad Reyes; Gaudreault, Nathalie; Olivas, Victor R.; Kumar, Nikit; Posada, Jessica M.; Birkeland, Andrew C.; Rapp, Joseph H.; Raffai, Robert L.

    2012-01-01

    Objective Apolipoprotein (apo) E4 is an established risk factor for atherosclerosis, but the structural components underlying this association remain unclear. ApoE4 is characterized by two biophysical properties: domain interaction and molten globule state. Substituting Arg-61 for Thr-61 in mouse apoE introduces domain interaction without molten globule state, allowing us to delineate potential pro-atherogenic effects of domain interaction in vivo. Methods and Results We studied atherosclerosis susceptibility of hypomorphic Apoe mice expressing either Thr-61 or Arg-61 apoE (ApoeTh/h or ApoeRh/h mice). On a chow diet, both mouse models were normo-lipidemic with similar levels of plasma apoE and lipoproteins. However, on a high cholesterol diet, ApoeRh/h mice displayed increased levels of total plasma cholesterol and VLDL as well as larger atherosclerotic plaques in the aortic root, arch and descending aorta compared to ApoeTh/h mice. In addition, evidence of cellular dysfunction was identified in peritoneal ApoeRh/h macrophages which released lower amounts of apoE in culture medium and displayed increased expression of MHC class II molecules. Conclusions These data indicate that domain interaction mediates pro-atherogenic effects of apoE4 in part by modulating lipoprotein metabolism and macrophage biology. Pharmaceutical targeting of domain interaction could lead to new treatments for atherosclerosis in apoE4 individuals. PMID:22441102

  4. Txnip ablation reduces vascular smooth muscle cell inflammation and ameliorates atherosclerosis in apolipoprotein E knockout mice.

    PubMed

    Byon, Chang Hyun; Han, Tieyan; Wu, Judy; Hui, Simon T

    2015-08-01

    Inflammation of vascular smooth muscle cells (VSMC) is intimately linked to atherosclerosis and other vascular inflammatory disease. Thioredoxin interacting protein (Txnip) is a key regulator of cellular sulfhydryl redox and a mediator of inflammasome activation. The goals of the present study were to examine the impact of Txnip ablation on inflammatory response to oxidative stress in VSMC and to determine the effect of Txnip ablation on atherosclerosis in vivo. Using cultured VSMC, we showed that ablation of Txnip reduced cellular oxidative stress and increased protection from oxidative stress when challenged with oxidized phospholipids and hydrogen peroxide. Correspondingly, expression of inflammatory markers and adhesion molecules were diminished in both VSMC and macrophages from Txnip knockout mice. The blunted inflammatory response was associated with a decrease in NF-ĸB nuclear translocation. Loss of Txnip in VSMC also led to a dramatic reduction in macrophage adhesion to VSMC. In vivo data from Txnip-ApoE double knockout mice showed that Txnip ablation led to 49% reduction in atherosclerotic lesion in the aortic root and 71% reduction in the abdominal aorta, compared to control ApoE knockout mice. Our data show that Txnip plays an important role in oxidative inflammatory response and atherosclerotic lesion development in mice. The atheroprotective effect of Txnip ablation implicates that modulation of Txnip expression may serve as a potential target for intervention of atherosclerosis and inflammatory vascular disease. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  5. Aspirin but not meloxicam attenuates early atherosclerosis in apolipoprotein E knockout mice.

    PubMed

    Kraus, Sarah; Naumov, Inna; Shapira, Shiran; Kazanov, Dina; Aroch, Ilan; Afek, Arnon; Eisenberg, Oded; George, Jacob; Arber, Nadir; Finkelstein, Ariel

    2014-04-01

    Atherosclerosis is a complex vascular inflammatory disease. In the last decade it was suggested that nonsteroidal anti-inflammatory drugs (NSAIDs) and in particular inhibition of cyclooxygenase (COX)-2 are associated with an increase in cardiovascular morbidity and mortality. Aspirin is known to reduce the incidence and mortality from ischemic heart disease and is a mainstay in the prevention of vascular complications of atherosclerosis. To examine the effect of meloxicam, a selective COX-2 inhibitor, or low dose aspirin on the development of experimental atherosclerosis in apoE knockout (KO) compared to wild-type (WT) mice. We aimed to test the hypothesis that meloxicam, a potential vasculitis inducer, would exacerbate atherosclerotic lesions while aspirin, which is known to reduce the incidence of thrombosis occlusive events, would increase protection in this model. We randomly divided 36 male apoE KO and 36 WT mice, 8 weeks old. Mice were treated for 10 weeks with 0.1 mg/ml aspirin, or 0.05 mg/ml meloxicam, dissolved in their drinking water. Control groups received regular drinking water. At sacrifice, the hearts were removed for histochemical staining and plaque size and composition were examined. Aspirin-treated animals displayed a decreased atherosclerotic lesion area compared to the untreated control mice, while meloxicam had a null effect on the extent of atherosclerosis in Apo E KO mice. These results suggest that low dose aspirin reduces early atherosclerosis, while inhibition of COX-2 by meloxicam is not associated with an increase in atherosclerotic plaque size in this mouse model.

  6. A novel apolipoprotein C-II mimetic peptide that activates lipoprotein lipase and decreases serum triglycerides in apolipoprotein E-knockout mice.

    PubMed

    Amar, Marcelo J A; Sakurai, Toshihiro; Sakurai-Ikuta, Akiko; Sviridov, Denis; Freeman, Lita; Ahsan, Lusana; Remaley, Alan T

    2015-02-01

    Apolipoprotein A-I (apoA-I) mimetic peptides are currently being developed as possible new agents for the treatment of cardiovascular disease based on their ability to promote cholesterol efflux and their other beneficial antiatherogenic properties. Many of these peptides, however, have been reported to cause transient hypertriglyceridemia due to inhibition of lipolysis by lipoprotein lipase (LPL). We describe a novel bihelical amphipathic peptide (C-II-a) that contains an amphipathic helix (18A) for binding to lipoproteins and stimulating cholesterol efflux as well as a motif based on the last helix of apolipoprotein C-II (apoC-II) that activates lipolysis by LPL. The C-II-a peptide promoted cholesterol efflux from ATP-binding cassette transporter ABCA1-transfected BHK cells similar to apoA-I mimetic peptides. Furthermore, it was shown in vitro to be comparable to the full-length apoC-II protein in activating lipolysis by LPL. When added to serum from a patient with apoC-II deficiency, it restored normal levels of LPL-induced lipolysis and also enhanced lipolysis in serum from patients with type IV and V hypertriglyceridemia. Intravenous injection of C-II-a (30 mg/kg) in apolipoprotein E-knockout mice resulted in a significant reduction of plasma cholesterol and triglycerides of 38 ± 6% and 85 ± 7%, respectively, at 4 hours. When coinjected with the 5A peptide (60 mg/kg), the C-II-a (30 mg/kg) peptide was found to completely block the hypertriglyceridemic effect of the 5A peptide in C57Bl/6 mice. In summary, C-II-a is a novel peptide based on apoC-II, which promotes cholesterol efflux and lipolysis and may therefore be useful for the treatment of apoC-II deficiency and other forms of hypertriglyceridemia. U.S. Government work not protected by U.S. copyright.

  7. Chemokine binding protein ‘M3’ limits atherosclerosis in apolipoprotein E-/- mice

    PubMed Central

    Ravindran, Dhanya; Ridiandries, Anisyah; Vanags, Laura Z.; Henriquez, Rodney; Cartland, Siân; Tan, Joanne T. M.; Bursill, Christina A.

    2017-01-01

    Chemokines are important in macrophage recruitment and the progression of atherosclerosis. The ‘M3’ chemokine binding protein inactivates key chemokines involved in atherosclerosis (e.g. CCL2, CCL5 and CX3CL1). We aimed to determine the effect of M3 on plaque development and composition. In vitro chemotaxis studies confirmed that M3 protein inhibited the activity of chemokines CCL2, CCL5 and CX3CL1 as primary human monocyte migration as well as CCR2-, CCR5- and CX3CR1-directed migration was attenuated by M3. In vivo, adenoviruses encoding M3 (AdM3) or green fluorescence protein (AdGFP; control) were infused systemically into apolipoprotein (apo)-E-/- mice. Two models of atherosclerosis development were used in which the rate of plaque progression was varied by diet including: (1) a ‘rapid promotion’ model (6-week high-fat-fed) and (2) a ‘slow progression’ model (12-week chow-fed). Plasma chemokine activity was suppressed in AdM3-infused mice as indicated by significantly less monocyte migration towards AdM3 mouse plasma ex vivo (29.56%, p = 0.014). In the ‘slow progression’ model AdM3 mice had reduced lesion area (45.3%, p = 0.035) and increased aortic smooth muscle cell α-actin expression (60.3%, p = 0.014). The reduction in lesion size could not be explained by changes in circulating inflammatory monocytes as they were higher in the AdM3 group. In the ‘rapid promotion’ model AdM3 mice had no changes in plaque size but reduced plaque macrophage content (46.8%, p = 0.006) and suppressed lipid deposition in thoracic aortas (66.9%, p<0.05). There was also a reduction in phosphorylated p65, the active subunit of NF-κb, in the aortas of AdM3 mice (37.3%, p<0.0001). M3 inhibited liver CCL2 concentrations in both models with no change in CCL5 or systemic chemokine levels. These findings show M3 causes varying effects on atherosclerosis progression and plaque composition depending on the rate of lesion progression. Overall, our studies support a

  8. Ultrasound Biomicroscopic Imaging for Interleukin-1 Receptor Antagonist–Inhibiting Atherosclerosis and Markers of Inflammation in Atherosclerotic Development in Apolipoprotein-E Knockout Mice

    PubMed Central

    Li, Rong-Juan; Sun, Yan; Wang, Qin; Yang, Jiao; Song, Li; Wang, Zheng; Luo, Xiang-Hong; Su, Rui-Juan

    2015-01-01

    We sought to validate the hypothesis that the development of atherosclerosis can be suppressed by the interleukin-1 receptor antagonist (IL-1Ra) in murine models of atherosclerosis in vivo, noninvasively seen by means of high-resolution ultrasound biomicroscopy, and we studied changes in inflammatory markers such as IL-1 and C-reactive protein (CRP) plasma levels in these models of atherosclerosis. We divided IL-1Ra+/−/apolipoprotein-E (apoE)−/− and IL-1Ra+/+/apoE−/− mice into 2 age groups, used as atherosclerotic models. The control groups were age-matched IL-1Ra+/+/apoE+/+ mice. Plaque thickness was measured in the ascending aorta in short-axis images by means of ultrasound and histology. Plasma levels of IL-1 and CRP were quantified in the 3 murine groups. At 16 weeks, plaque thickness in the ascending aortas of the IL-1Ra+/−/apoE−/− mice was significantly greater than that in the IL-1Ra+/+/apoE−/− mice, on ultrasound and histology (P <0.01). In contrast, at 32 weeks, the differences between these 2 genotypes were not statistically significant. Serum IL-1 levels were lower in the IL-1Ra+/−/apoE−/− mice than in the IL-1Ra+/+/apoE−/− mice at 16 and 32 weeks (P <0.05). At 16 weeks, serum CRP levels in the IL-1Ra+/−/apoE−/− mice were higher than in the IL-1Ra+/+/apoE−/− mice (P <0.01). Our results suggest that ultrasound biomicroscopy enables evaluation of atherosclerotic lesions in vivo, noninvasively and in real-time, in apoE−/− mice. Partial IL-1Ra deficiencies might promote early plaque development in 16-week-old apoE−/− mice. The balance of IL-1 and IL-1Ra might influence atherosclerotic development. Finally, CRP might affect the initiation of atherosclerosis, rather than its progression. PMID:26413013

  9. Knowledge of the biological actions of extra virgin olive oil gained from mice lacking apolipoprotein E.

    PubMed

    Guillén, Natalia; Acín, Sergio; Navarro, María A; Surra, Joaquín Carlos; Arnal, Carmen; Lou-Bonafonte, José Manuel; Muniesa, Pedro; Martínez-Gracia, María Victoria; Osada, Jesús

    2009-03-01

    The low incidence of cardiovascular disease in countries bordering the Mediterranean basin, where olive oil is the main source of dietary fat, has stimulated interest in the chemical composition of olive oil and in the production of other oils enriched with its minor components. This review summarizes what has been learned about the effects of different olive oil preparations on the development of atherosclerosis and about the prognostic value of associated plasma variables in the disease from experiments on genetically modified mice that spontaneously develop atherosclerosis. The limitations of this animal model associated with its morphological and physiological differences with humans are minimized by the similarity of the two genomes and by the potential for increased understanding attainable, given that the dietary interventions reported here would have taken 400 years to achieve in humans. As observed in traditional Mediterranean populations, it has been confirmed that extra virgin olive oil is beneficial when consumed judiciously and in a diet that is low in cholesterol due to the relative scarcity of animal products. Furthermore, the use of genomic techniques has led to the identification of new markers of response to olive oil. In conclusion, multidisciplinary research into extra virgin olive oil is expanding our knowledge of the substance's biological properties.

  10. Selective effect of conjugated linoleic acid isomers on atherosclerotic lesion development in apolipoprotein E knockout mice.

    PubMed

    Arbonés-Mainar, José M; Navarro, María A; Guzmán, Mario A; Arnal, Carmen; Surra, Joaquín C; Acín, Sergio; Carnicer, Ricardo; Osada, Jesús; Roche, Helen M

    2006-12-01

    Research suggests that conjugated linoleic acid (CLA) may inhibit atherosclerosis, but there are contradictory results in different animal models fed heterogeneous mixtures of CLA isomers. This study addressed the hypothesis that the individual CLA isomers may exert different atherogenic properties. ApoE(-/-) mice were fed isocaloric, isonitrogenous westernized diets containing 0.15% cholesterol and enriched with 1% (w/w) cis-9,trans-11-CLA (c9,t11-CLA), trans-10,cis-12-CLA (t10,c12-CLA) or linoleic acid (control diet) for 12 weeks. At the end of the dietary intervention, the effects of CLA isomers on the development of atherosclerotic vascular lesions, lipid metabolism, inflammation and oxidative stress were assessed. The t10,c12-CLA diet had a profound pro-atherogenic effect, whereas c9,t11-CLA impeded the development of atherosclerosis. En face aortic lesion assessment showed more dorsal and lumbar extensions presenting atherosclerotic foci after the t10,c12-CLA diet. Furthermore, animals fed t10,c12-CLA had pronounced hyperlipidemia, higher 8-iso-prostaglandin F(2alpha) levels, higher vulnerable atherosclerotic plaque with a lower smooth muscle and fibre contents and higher macrophage content and activation, assayed as plasma chitotriosidase compared to the control or c9,t11-CLA dietary groups. Plasma chitotriosidase activity was more closely associated with the extent of the plaque than with MOMA staining or than monocyte chemoattractant protein-1 levels. Our results demonstrate that CLA isomers differentially modulate the development of atherosclerosis, c9,t11-CLA impedes, whereas t10,c12-CLA promotes atherosclerosis. These opposing effects may be ascribed to divergent effects on lipid, oxidative, inflammatory and fibro muscular components of this pathology. Plasma chitotriosidase is a better indicator of dietary fat interventions that alter plaque monocyte activity in this murine model.

  11. Liver-specific Deficiency of Serine Palmitoyltransferase Subunit 2 Decreases Plasma Sphingomyelin and Increases Apolipoprotein E Levels*

    PubMed Central

    Li, Zhiqiang; Li, Yan; Chakraborty, Mahua; Fan, Yifan; Bui, Hai H.; Peake, David A.; Kuo, Ming-Shang; Xiao, Xiao; Cao, Guoqing; Jiang, Xian-Cheng

    2009-01-01

    Sphingomyelin (SM) is one of the major lipid components of plasma lipoproteins. Serine palmitoyltransferase (SPT) is the key enzyme in SM biosynthesis. Mice totally lacking in SPT are embryonic lethal. The liver is the major site for plasma lipoprotein biosynthesis, secretion, and degradation, and in this study we utilized a liver-specific knock-out approach for evaluating liver SPT activity and also its role in plasma SM and lipoprotein metabolism. We found that a deficiency of liver-specific Sptlc2 (a subunit of SPT) decreased liver SPT protein mass and activity by 95 and 92%, respectively, but had no effect on other tissues. Liver Sptlc2 deficiency decreased plasma SM levels (in both high density lipoprotein and non-high density lipoprotein fractions) by 36 and 35% (p < 0.01), respectively, and increased phosphatidylcholine levels by 19% (p < 0.05), thus increasing the phosphatidylcholine/SM ratio by 77% (p < 0.001), compared with controls. This deficiency also decreased SM levels in the liver by 38% (p < 0.01) and in the hepatocyte plasma membranes (based on a lysenin-mediated cell lysis assay). Liver-specific Sptlc2 deficiency significantly increased hepatocyte apoE secretion and thus increased plasma apoE levels 3.5-fold (p < 0.0001). Furthermore, plasma from Sptlc2 knock-out mice had a significantly stronger potential for promoting cholesterol efflux from macrophages than from wild-type mice (p < 0.01) because of a greater amount of apoE in the circulation. As a result of these findings, we believe that the ability to control liver SPT activity could result in regulation of lipoprotein metabolism and might have an impact on the development of atherosclerosis. PMID:19648608

  12. Targeting mannose receptor expression on macrophages in atherosclerotic plaques of apolipoprotein E-knockout mice using (111)In-tilmanocept.

    PubMed

    Varasteh, Zohreh; Hyafil, Fabien; Anizan, Nadège; Diallo, Devy; Aid-Launais, Rachida; Mohanta, Sarajo; Li, Yuanfang; Braeuer, Miriam; Steiger, Katja; Vigne, Jonathan; Qin, Zhengtao; Nekolla, Stephan G; Fabre, Jean-Etienne; Döring, Yvonne; Le Guludec, Dominique; Habenicht, Andreas; Vera, David R; Schwaiger, Markus

    2017-12-01

    Atherosclerotic plaque phenotypes are classified based on the extent of macrophage infiltration into the lesions, and the presence of certain macrophage subsets might be a sign for plaque vulnerability. The mannose receptor (MR) is over-expressed in activated macrophages. Tilmanocept is a tracer that targets MR and is approved in Europe and the USA for the detection of sentinel lymph nodes. In this study, our aim was to evaluate the potential of (111)In-labelled tilmanocept for the detection of MR-positive macrophages in atherosclerotic plaques of apolipoprotein E-knockout (ApoE-KO) mouse model. Tilmanocept was labelled with (111)In. The labelling stability and biodistribution of the tracer was first evaluated in control mice (n = 10) 1 h post injection (p.i.). For in vivo imaging studies, (111)In-tilmanocept was injected into ApoE-KO (n = 8) and control (n = 8) mice intravenously (i.v.). The mice were scanned 90 min p.i. using a dedicated animal SPECT/CT. For testing the specificity of (111)In-tilmanocept uptake in plaques, a group of ApoE-KO mice was co-injected with excess amount of non-labelled tilmanocept. For ex vivo imaging studies, the whole aortas (n = 9 from ApoE-KO and n = 4 from control mice) were harvested free from adventitial tissue for Sudan IV staining and autoradiography. Cryosections were prepared for immunohistochemistry (IHC). (111)In radiolabelling of tilmanocept provided a yield of greater than 99%. After i.v. injection, (111)In-tilmanocept accumulated in vivo in MR-expressing organs (i.e. liver and spleen) and showed only low residual blood signal 1 h p.i. MR-binding specificity in receptor-positive organs was demonstrated by a 1.5- to 3-fold reduced uptake of (111)In-tilmanocept after co-injection of a blocking dose of non-labelled tilmanocept. Focal signal was detected in atherosclerotic plaques of ApoE-KO mice, whereas no signal was detected in the aortas of control mice. (111)In-tilmanocept uptake was detected in

  13. Inhibition of glycosphingolipid synthesis ameliorates atherosclerosis and arterial stiffness in apolipoprotein E-/- mice and rabbits fed a high-fat and -cholesterol diet.

    PubMed

    Chatterjee, Subroto; Bedja, Djahida; Mishra, Sumita; Amuzie, Christine; Avolio, Alberto; Kass, David A; Berkowitz, Dan; Renehan, Mark

    2014-06-10

    Glycosphingolipids, integral components of the cell membrane, have been shown to serve as messengers, transducing growth factor-initiated phenotypes. Here, we have examined whether inhibition of glycosphingolipid synthesis could ameliorate atherosclerosis and arterial stiffness in transgenic mice and rabbits. Apolipoprotein E(-/-) mice (12 weeks of age; n=6) were fed regular chow or a Western diet (1.25% cholesterol, 2% fat). Mice were fed 5 or 10 mg/kg of an inhibitor of glycosphingolipid synthesis, D-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (D-PDMP), solubilized in vehicle (5% Tween-80 in PBS); the placebo group received vehicle only. At 20 and 36 weeks of age, serial echocardiography was performed to measure aortic intima-media thickening. Aortic pulse-wave velocity measured vascular stiffness. Feeding mice a Western diet markedly increased aortic pulse-wave velocity, intima-media thickening, oxidized low-density lipoprotein, Ca(2+) deposits, and glucosylceramide and lactosylceramide synthase activity. These were dose-dependently decreased by feeding D-PDMP. In liver, D-PDMP decreased cholesterol and triglyceride levels by raising the expression of SREBP2, low-density lipoprotein receptor, HMGCo-A reductase, and the cholesterol efflux genes (eg, ABCG5, ABCG8). D-PDMP affected very-low-density lipoprotein catabolism by increasing the gene expression for lipoprotein lipase and very-low-density lipoprotein receptor. Rabbits fed a Western diet for 90 days had extensive atherosclerosis accompanied by a 17.5-fold increase in total cholesterol levels and a 3-fold increase in lactosylceramide levels. This was completely prevented by feeding D-PDMP. Inhibition of glycosphingolipid synthesis ameliorates atherosclerosis and arterial stiffness in apolipoprotein E(-/-) mice and rabbits. Thus, inhibition of glycosphingolipid synthesis may be a novel approach to ameliorate atherosclerosis and arterial stiffness. © 2014 American Heart Association, Inc.

  14. Long-Term Effects of {sup 56}Fe Irradiation on Spatial Memory of Mice: Role of Sex and Apolipoprotein E Isoform

    SciTech Connect

    Villasana, Laura E.; Benice, Theodore S.; Raber, Jacob

    2011-06-01

    Purpose: To assess whether the effects of cranial {sup 56}Fe irradiation on the spatial memory of mice in the water maze are sex and apolipoprotein E (apoE) isoform dependent and whether radiation-induced changes in spatial memory are associated with changes in the dendritic marker microtubule-associated protein 2 (MAP-2) and the presynaptic marker synaptophysin. Methods and Materials: Two-month-old male and female mice expressing human apoE3 or apoE4 received either a 3-Gy dose of cranial {sup 56}Fe irradiation (600 MeV/amu) or sham irradiation. Mice were tested in a water maze task 13 months later to assess effects of irradiation on spatial memory retention. After behavioral testing, the brain tissues of these mice were analyzed for synaptophysin and MAP-2 immunoreactivity. Results: After irradiation, spatial memory retention of apoE3 female, but not male, mice was impaired. A general genotype deficit in spatial memory was observed in sham-irradiated apoE4 mice. Strikingly, irradiation prevented this genotype deficit in apoE4 male mice. A similar but nonsignificant trend was observed in apoE4 female mice. Although there was no change in MAP-2 immunoreactivity after irradiation, synaptophysin immunoreactivity was increased in irradiated female mice, independent of genotype. Conclusions: The effects of {sup 56}Fe irradiation on the spatial memory retention of mice are critically influenced by sex, and the direction of these effects is influenced by apoE isoform. Although in female mice synaptophysin immunoreactivity provides a sensitive marker for effects of irradiation, it cannot explain the apoE genotype-dependent effects of irradiation on the spatial memory retention of the mice.

  15. Acai juice attenuates atherosclerosis in apoe deficient mice through antioxidant and anti-inflammatory activities

    USDA-ARS?s Scientific Manuscript database

    Objective - Acai fruit pulp has received much attention because of its high antioxidant capacity and potential anti-inflammatory effects. In this study, athero-protective effects of açaí juice were investigated in apolipoprotein E deficient (apoE -/-) mice. Methods and Results - ApoE-/- mice were f...

  16. Apolipoprotein E (APOE) genotype and the pesticide chlorpyrifos modulate attention, motivation and impulsivity in female mice in the 5-choice serial reaction time task.

    PubMed

    Peris-Sampedro, Fiona; Reverte, Ingrid; Basaure, Pia; Cabré, Maria; Domingo, José L; Colomina, Maria Teresa

    2016-06-01

    Organophosphate pesticides - and chlorpyrifos (CPF) in particular - contribute to a wide range of neurobehavioural disorders. Most experimental research focuses on learning and memory processes, while other behaviours remain understudied. The isoforms of the human apolipoprotein E (apoE) confer different cognitive skills on their carriers, but data on this topic are still limited. The current study was performed to assess whether the APOE genotypic variability differently modulates the effects of CPF on attentional performance, inhibitory control and motivation. Human apoE targeted replacement adult female mice (apoE2, apoE3 and apoE4) were trained to stably perform the 5-choice serial reaction time task (5-CSRTT). Animals were then subjected to daily dietary CPF (3.75 mg/kg body weight) for 4 weeks. After CPF exposure, we established a 4-week CPF-free period to assess recovery. All individuals acquired the task, apoE2 mice showed enhanced learning, while apoE4 mice displayed increased premature and perseverative responding. This genotype-dependent lack of inhibitory control was reversed by CPF. Overall, the pesticide induced protracted impairments in sustained attention and motivation, and it reduced anticipatory responding. ApoE3 mice exhibited delayed attentional disruptions throughout the wash-out period. Taken together, these findings provide notable evidence on the emergence of CPF-related attentional and motivational deficits. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Blocking the Apolipoprotein E/Amyloid β Interaction in Triple Transgenic Mice Ameliorates Alzheimer’s Disease Related Amyloid β and Tau Pathology

    PubMed Central

    Liu, Shan; Breitbart, Ariel; Sun, Yanjie; Mehta, Pankaj D.; Boutajangout, Allal; Scholtzova, Henrieta; Wisniewski, Thomas

    2013-01-01

    Inheritance of the apolipoprotein E4 (apoE4) genotype has been identified as the major genetic risk factor for late-onset Alzheimer’s disease (AD). Studies have shown that the binding between apoE and amyloid-β (Aβ) peptides occurs at residues 244–272 of apoE and residues 12–28 of Aβ. ApoE4 has been implicated in promoting Aβ deposition and impairing clearance of Aβ. We hypothesized that blocking the apoE/Aβ interaction would serve as an effective new approach to AD therapy. We have previously shown that treatment with Aβ12–28P can reduce amyloid plaques in APP/PS1 transgenic (Tg) mice and vascular amyloid in TgSwDI mice with congophilic amyloid angiopathy (CAA). In the present study, we investigated whether the Aβ12–28P elicits a therapeutic effect on tau-related pathology in addition to amyloid pathology using old triple transgenic Alzheimer’s disease mice (3xTg, with PS1M146V, APPSwe and tauP30IL transgenes) with established pathology from the ages of 21 to 26 months. We show that treatment with Aβ12–28P substantially reduces tau pathology both immunohistochemically and biochemically, as well as reducing the amyloid burden and suppressing the activation of astrocytes and microglia. These affects correlate with a behavioral amelioration in the treated Tg mice. PMID:24117759

  18. H1-antihistamines exacerbate high-fat diet-induced hepatic steatosis in wild-type but not in apolipoprotein E knockout mice

    PubMed Central

    Raveendran, Vineesh V.; Kassel, Karen M.; Smith, Donald D.; Luyendyk, James P.; Williams, Kurt J.; Cherian, Rachel; Reed, Gregory A.; Flynn, Colleen A.; Csanaky, Iván L.; Lickteig, Andrew L.; Pratt-Hyatt, Matthew J.; Klaassen, Curtis D.

    2014-01-01

    We examined the effects of two over-the-counter H1-antihistamines on the progression of fatty liver disease in male C57Bl/6 wild-type and apolipoprotein E (ApoE)−/− mice. Mice were fed a high-fat diet (HFD) for 3 mo, together with administration of either cetirizine (4 mg/kg body wt) or fexofenadine (40 mg/kg body wt) in drinking water. Antihistamine treatments increased body weight gain, gonadal fat deposition, liver weight, and hepatic steatosis in wild-type mice but not in ApoE−/− mice. Lobular inflammation, acute inflammation, and necrosis were not affected by H1-antihistamines in either genotype. Serum biomarkers of liver injury tended to increase in antihistamine-treated wild-type mice. Serum level of glucose was increased by fexofenadine, whereas lipase was increased by cetirizine. H1-antihistamines reduced the mRNA expression of ApoE and carbohydrate response element-binding protein in wild-type mice, without altering the mRNA expression of sterol regulatory element-binding protein 1c, fatty acid synthase, or ApoB100, in either genotype. Fexofenadine increased both triglycerides and cholesterol ester, whereas cetirizine increased only cholesterol ester in liver, with a concomitant decrease in serum triglycerides by both antihistamines in wild-type mice. Antihistamines increased hepatic levels of conjugated bile acids in wild-type mice, with the effect being significant in fexofenadine-treated animals. The increase was associated with changes in the expression of organic anion transport polypeptide 1b2 and bile salt export pump. These results suggest that H1-antihistamines increase the progression of fatty liver disease in wild-type mice, and there seems to be an association between the severity of disease, presence of ApoE, and increase in hepatic bile acid levels. PMID:24852568

  19. A 10-bp deletion in the apolipoprotein epsilon gene causing apolipoprotein E deficiency and severe type III hyperlipoproteinemia.

    PubMed Central

    Feussner, G.; Dobmeyer, J.; Gröne, H. J.; Lohmer, S.; Wohlfeil, S.

    1996-01-01

    Type III hyperlipoproteinemia (HLP) is usually associated with homozygosity for apolipoprotein (apo) E2. We identified a 30-year-old male German of Hungarian ancestry with severe type III HLP and apo E deficiency. The disease was expressed in an extreme phenotype with multiple cutaneous xanthomas. Apo E was detectable only in trace amounts in plasma but not in the different lipoprotein fractions. Direct sequencing of PCR-amplified segments of the apo epsilon gene identified a 10-bp deletion in exon 4 (bp 4037-4046 coding for amino acids 209-212 of the mature protein). The mutation is predictive for a reading frameshift introducing a premature stop codon (TGA) at amino acid 229. By western blot analysis, we found small amounts of a truncated apo E in the patient's plasma. Family analysis revealed that the proband was homozygous--and 10 of 24 relatives were heterozygous--for the mutation. Heterozygotes had, as compared to unaffected family members, significantly higher triglycerides (TG), very low-density lipoprotein (VLDL) cholesterol and a significantly higher VLDL cholesterol-to-serum TG ratio, which is indicative of a delayed remnant catabolism. We propose that the absence of a functionally active apo E is the cause of the severe type III HLP in the patient and that the mutation, even in a single dose in heterozygotes, predisposes in variable severity to the phenotypic expression of the disease. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:8571954

  20. Baicalin inhibits the expression of monocyte chemoattractant protein-1 and interleukin-6 in the kidneys of apolipoprotein E-knockout mice fed a high cholesterol diet.

    PubMed

    Liu, Lihua; Liao, Pingping; Wang, Bin; Fang, Xin; Li, Wei; Guan, Siming

    2015-05-01

    Hyperlipidemia is considered an independent risk factor for renal dysfunction and induces a significant increase in the expression of inflammatory mediators, which can be used to evaluate the degree of renal injury. Baicalin is widely used in traditional Chinese herbal medicine and has multiple pharmacological effects. The present study investigated whether baicalin can attenuate the expression of vascular cell adhesion molecule 1 (VCAM‑1) via a reduction in the expression of monocyte chemoattractant protein‑1 (MCP‑1) and interleukin‑6 (IL‑6) in the kidney of apolipoprotein E (ApoE)‑knockout (KO) mice fed a high cholesterol diet. These mice were used as a model of atherosclerosis and were treated with baicalin (100 mg/kg/day) daily by gavage for a period of 12 weeks. By contrast, wild‑type male C57BL/6J mice were fed a standard diet. Blood samples were obtained from the angular veins of the mice to measure the total cholesterol (TC) and the expression levels of VCAM‑1, MCP‑1 and IL‑6 in the kidney tissues of the mice were analyzed using reverse transcription quantitative polymerase chain reaction and western blot analysis. Following oral administration of baicalin, no significant difference was observed in the TC in the baicalin group compared with the high cholesterol diet control group. The TC was significantly higher in the AopE‑KO mice compared with the wild‑type male C57BL/6J mice. The expression levels of VCAM‑1, MCP‑1 and IL‑6 in the kidney tissues of the baicalin group were lower compared with those in the high cholesterol diet control group. The results suggested that baicalin decreased the expression levels of pro‑inflammatory mediators and prevented kidney dysfunction in the ApoE‑KO mice fed a high cholesterol diet.

  1. Apolipoprotein E-Deficient Lipoproteins Induce Foam Cell Formation by Activation of PERK-EIF-2α Signaling Cascade

    PubMed Central

    Zhao, YanFeng; Guo, ZhongMao; Lin, XingHua; Zhou, LiChun; Okoro, Emmanuel U.; Fan, GuoHuang; Ramaswamy, Raju; Yang, Hong

    2011-01-01

    Transformation of macrophages into foam cells by apolipoprotein (Apo) E-deficient, ApoB48-containing (E−/B48) lipoproteins has been shown to be associated with increased phosphorylation of eukaryotic initiation factor-2α (eIF-2α). The present report examined the causal relationship between eIF-2α phosphorylation and lipid accumulation in macrophages induced by E−/B48 lipoproteins. E−/B48 lipoproteins increased eIF-2α phosphorylation and cholesterol ester accumulation, while lipoprotein degradation decreased and lysosomal acid lipase and cathepsin B mRNA translation was inhibited in mouse peritoneal macrophages (MPMs). These responses were overcome by overexpression of a nonphosphorylatable eIF-2α mutant in MPMs. Incubation of MPMs with E−/B48 lipoproteins also increased the phosphorylation of RNA-dependent protein kinase-like endoplasmic reticulum kinase (PERK), but not other eIF-2α kinases. Overexpression of a nonphosphorylatable PERK mutant inhibited PERK and eIF-2α phosphorylation, and alleviated cholesterol ester accumulation induced by E−/B48 lipoproteins. PERK is an eIF-2α kinase activated by endoplasmic reticulum (ER) stress. Taken together, findings from this report suggest that induction of ER stress, i.e., activation of the PERK-eIF2α signaling cascade, is a mechanism by which E−/B48 lipoproteins down-regulate lysosomal hydrolase synthesis, inhibit lysosomal lipoprotein degradation, and increase intracellular lipoprotein and cholesterol ester accumulation, resulting in foam cell formation. PMID:21552349

  2. Treatment with bexarotene, a compound that increases apolipoprotein-E, provides no cognitive benefit in mutant APP/PS1 mice

    PubMed Central

    2013-01-01

    Background Though the precise cause(s) of Alzheimer’s disease (AD) remain unknown, there is strong evidence that decreased clearance of β-amyloid (Aβ) from the brain can contribute to the disease. Therapeutic strategies to promote natural Aβ clearance mechanisms, such as the protein apolipoprotein-E (APOE), hold promise for the treatment of AD. The amount of APOE in the brain is regulated by nuclear receptors including retinoid X receptors (RXRs). Drugs that activate RXRs, including bexarotene, can increase APOE and ABCA1 production, and have been shown to decrease the Aβ burden and improve cognition in mouse models of Aβ amyloidosis. Although recent bexarotene studies failed to replicate the rapid clearance of Aβ from brains, behavioral and cognitive effects of this compound remain controversial. Findings In efforts to clarify these behavioral findings, mutant APP/PS1 mice were acutely dosed with bexarotene. While ABCA1 was upregulated in mutant APP/PS1 mice treated with bexarotene, this drug failed to attenuate Aβ plaques or cognitive deficits in these mice. Conclusions We recommend rigorous preclinical study to evaluate the mechanism and utility of such a compound for AD therapy. PMID:23764200

  3. Crossroads between peripheral atherosclerosis, western-type diet and skeletal muscle pathophysiology: emphasis on apolipoprotein E deficiency and peripheral arterial disease.

    PubMed

    Sfyri, Peggy; Matsakas, Antonios

    2017-07-08

    Atherosclerosis is a chronic inflammatory process that, in the presence of hyperlipidaemia, promotes the formation of atheromatous plaques in large vessels of the cardiovascular system. It also affects peripheral arteries with major implications for a number of other non-vascular tissues such as the skeletal muscle, the liver and the kidney. The aim of this review is to critically discuss and assimilate current knowledge on the impact of peripheral atherosclerosis and its implications on skeletal muscle homeostasis. Accumulating data suggests that manifestations of peripheral atherosclerosis in skeletal muscle originates in a combination of increased i)-oxidative stress, ii)-inflammation, iii)-mitochondrial deficits, iv)-altered myofibre morphology and fibrosis, v)-chronic ischemia followed by impaired oxygen supply, vi)-reduced capillary density, vii)- proteolysis and viii)-apoptosis. These structural, biochemical and pathophysiological alterations impact on skeletal muscle metabolic and physiologic homeostasis and its capacity to generate force, which further affects the individual's quality of life. Particular emphasis is given on two major areas representing basic and applied science respectively: a)-the abundant evidence from a well-recognised atherogenic model; the Apolipoprotein E deficient mouse and the role of a western-type diet and b)-on skeletal myopathy and oxidative stress-induced myofibre damage from human studies on peripheral arterial disease. A significant source of reactive oxygen species production and oxidative stress in cardiovascular disease is the family of NADPH oxidases that contribute to several pathologies. Finally, strategies targeting NADPH oxidases in skeletal muscle in an attempt to attenuate cellular oxidative stress are highlighted, providing a better understanding of the crossroads between peripheral atherosclerosis and skeletal muscle pathophysiology.

  4. Effects of pyrophosphate delivery in a peritoneal dialysis solution on bone tissue of apolipoprotein-E knockout mice with chronic kidney disease.

    PubMed

    Barreto, Fellype C; de Oliveira, Rodrigo B; Benchitrit, Joyce; Louvet, Loïc; Rezg, Raja; Poirot, Sabrina; Jorgetti, Vanda; Drüeke, Tilman B; Riser, Bruce L; Massy, Ziad A

    2014-11-01

    Vascular calcification (VC) is a risk factor for cardiovascular mortality in the setting of chronic kidney disease (CKD). Pyrophosphate (PPi), an endogenous molecule that inhibits hydroxyapatite crystal formation, has been shown to prevent the development of VC in animal models of CKD. However, the possibility of harmful effects of exogenous administration of PPi on bone requires further investigation. To this end, we examined by histomorphometry the bone of CKD mice after intraperitoneal PPi administration. After CKD creation or sham surgery, 10-week-old female apolipoprotein-E knockout (apoE(-/-)) mice were randomized to one non-CKD group or 4 CKD groups (n = 10-35/group) treated with placebo or three distinct doses of PPi, and fed with standard diet. Eight weeks later, the animals were killed. Serum and femurs were sampled. Femurs were processed for bone histomorphometry. Placebo-treated CKD mice had significantly higher values of osteoid volume, osteoid surface and bone formation rate than sham-placebo mice with normal renal function. Slightly higher osteoid values were observed in CKD mice in response to very low PPi dose (OV/BV, O.Th and ObS/BS) and, for one parameter measured, to high PPi dose (O.Th), compared to placebo-treated CKD mice. Treatment with PPi did not modify any other structural parameters. Mineral apposition rates, and other parameters of bone formation and resorption were not significantly different among the treated animal groups or control CKD placebo group. In conclusion, PPi does not appear to be deleterious to bone tissue in apoE(-/-) mice with CKD, although a possible stimulatory PPi effect on osteoid formation may be worth further investigation.

  5. High-Fat Diet Changes Hippocampal Apolipoprotein E (ApoE) in a Genotype- and Carbohydrate-Dependent Manner in Mice

    PubMed Central

    Lane-Donovan, Courtney; Herz, Joachim

    2016-01-01

    Alzheimer’s disease is a currently incurable neurodegenerative disease affecting millions of individuals worldwide. Risk factors for Alzheimer’s disease include genetic risk factors, such as possession of ε4 allele of apolipoprotein E (ApoE4) over the risk-neutral ApoE3 allele, and lifestyle risk factors, such as diet and exercise. The intersection of these two sources of disease risk is not well understood. We investigated the impact of diet on ApoE levels by feeding wildtype, ApoE3, and ApoE4 targeted replacement (TR) mice with chow, high-fat, or ketogenic (high-fat, very-low-carbohydrate) diets. We found that high-fat diet affected both plasma and hippocampal levels of ApoE in an isoform-dependent manner, with high-fat diet causing a surprising reduction of hippocampal ApoE levels in ApoE3 TR mice. Conversely, the ketogenic diet had no effect on hippocampal ApoE. Our findings suggest that the use of dietary interventions to slow the progression AD should take ApoE genotype into consideration. PMID:26828652

  6. High-Fat Diet Changes Hippocampal Apolipoprotein E (ApoE) in a Genotype- and Carbohydrate-Dependent Manner in Mice.

    PubMed

    Lane-Donovan, Courtney; Herz, Joachim

    2016-01-01

    Alzheimer's disease is a currently incurable neurodegenerative disease affecting millions of individuals worldwide. Risk factors for Alzheimer's disease include genetic risk factors, such as possession of ε4 allele of apolipoprotein E (ApoE4) over the risk-neutral ApoE3 allele, and lifestyle risk factors, such as diet and exercise. The intersection of these two sources of disease risk is not well understood. We investigated the impact of diet on ApoE levels by feeding wildtype, ApoE3, and ApoE4 targeted replacement (TR) mice with chow, high-fat, or ketogenic (high-fat, very-low-carbohydrate) diets. We found that high-fat diet affected both plasma and hippocampal levels of ApoE in an isoform-dependent manner, with high-fat diet causing a surprising reduction of hippocampal ApoE levels in ApoE3 TR mice. Conversely, the ketogenic diet had no effect on hippocampal ApoE. Our findings suggest that the use of dietary interventions to slow the progression AD should take ApoE genotype into consideration.

  7. High cholesterol diet results in increased expression of interleukin-6 and caspase-1 in the brain of apolipoprotein E knockout and wild type mice.

    PubMed

    Rahman, S M A; Van Dam, A-M; Schultzberg, M; Crisby, M

    2005-12-01

    Inflammation in the central nervous system is an early hallmark of many neurodegenerative diseases including Alzheimer's disease (AD). Recently, increasing evidence suggests that hypercholesterolemia during midlife and abnormalities in the cholesterol metabolism could have an important role in the pathogenesis of AD. In the present study, we have evaluated the effect of high cholesterol (HC) diet on the expression of interleukin-6 (IL-6), a cytokine involved in neurodegeneration, and caspase-1, that is responsible for the cleavage of the precursors of interleukin-1 beta (IL-1 beta) and interleukin-18 (IL-18) in the brain of apolipoprotein E (Apo E) knock-out (KO) and wild type (WT) mice. The density of IL-6-positive cells was increased in the hippocampus (p<0.0001) and the dorsal part of the cortex (p<0.001) of KO and WT mice on HC diet (KOHC and WTHC mice, respectively) compared to KO and WT mice on ND (KOND and WTND mice, respectively). KOHC mice had increased caspase-1 positive cells and staining intensity in the hippocampus in comparison with WTHC mice (p<0.01). In the hippocampus, the density of caspase-1 positive cells was also higher in KOHC compared to KOND mice (p<0.05) and KOHC compared with WTHC mice (p<0.01). There was a major increase in caspase-1 immunoreactivity and cell density in both the dosal part of the cortex (p<0.001) and the lateral part of the cortex (p<0.005) in KO and WT mice on HC diet compared to ND. The findings of the present study indicate that chronic exposure to HC diet increases the expression of the two important inflammatory mediators IL-6 and caspase-1 in the brain of KO and WT mice. In the case of caspase-1, we report a major difference in the effect of HC diet on the KO mice compared to WT mice in the hippocampus. Increased expression of inflammatory mediators involved in neurodegeneration could be a potential mechanism by which hypercholesterolemia and HC diet increase the risk of AD.

  8. Pharmacogenomic effects of apolipoprotein e on intracerebral hemorrhage.

    PubMed

    James, Michael L; Sullivan, Patrick M; Lascola, Christopher D; Vitek, Michael P; Laskowitz, Daniel T

    2009-02-01

    The purpose of the study was to evaluate the effect of APOE genotype and the feasibility of administering an apolipoprotein E-mimetic therapeutic to modify outcomes in a murine model of intracerebral hemorrhage. Intracerebral hemorrhage was induced via stereotactic injection of 0.1 U Clostridial collagenase into the left basal ganglia of wild-type and apolipoprotein-E targeted-replacement mice, consisting of either homozygous 3/3 or 4/4 genotypes. Animals were randomized to receive either vehicle or apolipoprotein E-mimetic peptide. Outcomes included functional neurological tests (21-point neuroseverity score and Rotorod latency) over the initial 7 days after injury, radiographic and histological hemorrhage size at 3 and 7 days, brain water content for cerebral edema at 24 hours, and quantitative polymerase chain reaction for inflammatory markers at 6, 24, and 48 hours. Apolipoprotein-E targeted-replacement mice consisting of homozygous 3/3 demonstrated superior neuroseverity scores and Rotorod latencies over the first 3 days after intracerebral hemorrhage, decreased cerebral edema at 24 hours, and reduced upregulation of IL-6 and endothelial nitric oxide synthase at 6 hours when compared to their apolipoprotein-E targeted-replacement mice consisting of homozygous 4/4 counterparts. After intravenous administration of 1 mg/kg apolipoprotein E-mimetic peptide, both wild-type and apolipoprotein-E targeted-replacement mice consisting of homozygous 4/4 exhibited improved functional outcomes over 7 days after intracerebral hemorrhage, less edema at 24 hours, and reduced upregulation of IL-6 and endothelial nitric oxide synthase when compared to mice that did not receive the peptide. Our data indicate that APOE genotype influences neurological outcome after intracerebral hemorrhage in a murine model. In particular APOE4 is associated with poor functional outcome and increased cerebral edema. Additionally, this outcome can be modified by the addition of an apolipoprotein E

  9. Human apolipoprotein E4 targeted replacement in mice reveals increased susceptibility to sleep disruption and intermittent hypoxia

    PubMed Central

    Kaushal, Navita; Ramesh, Vijay

    2012-01-01

    Intermittent hypoxia (IH) and sleep fragmentation (SF) are major manifestations of sleep apnea, a frequent condition in aging humans. Sleep perturbations are frequent in Alzheimer's disease (AD) and may underlie the progression of disease. We hypothesized that acute short-term IH, SF, and their combination (IH+SF) may reveal unique susceptibility in sleep integrity in a murine model of AD. The effects of acute IH, SF, and IH+SF on sleep architecture, delta power, sleep latency, and core body temperature were assessed in adult male human ApoE4-targeted replacement mice (hApoE4) and wild-type (WT) controls. Slow wave sleep (SWS) was significantly reduced, and rapid eye movement (REM) sleep was almost abolished during acute exposure to IH alone and IH+SF for 6 h in hApoE4, with milder effects in WT controls. Decreased delta power during SWS did not show postexposure rebound in hApoE4 unlike WT controls. IH and IH+SF induced hypothermia, which was more prominent in hApoE4 than WT controls. Mice subjected to SF also showed sleep deficits but without hypothermia. hApoE4 mice, unlike WT controls, exhibited increased sleep propensity, especially following IH and IH+SF, suggesting limited ability for sleep recovery in hApoE4 mice. These findings substantiate the potential impact of IH and SF in modulating sleep architecture and sleep homeostasis including maintenance of body temperature. Furthermore, the increased susceptibility and limited recovery ability of hApoE4 mice to sleep apnea suggests that early recognition and treatment of the latter in AD patients may restrict the progression and clinical manifestations of this frequent neurodegenerative disorder. PMID:22573105

  10. Generation of Aorta Transcript Atlases of Wild-Type and Apolipoprotein E-null Mice by Laser Capture Microdissection-Based mRNA Expression Microarrays.

    PubMed

    Yin, Changjun; Mohanta, Sarajo; Ma, Zhe; Weber, Christian; Hu, Desheng; Weih, Falk; Habenicht, Andreas

    2015-01-01

    Atherosclerosis is a transmural chronic inflammatory disease of medium and large arteries. Though it is well recognized that immune responses contribute to atherosclerosis, it remains unclear whether these responses are carried out in secondary lymphoid organs such as the spleen and lymph nodes and/or within the arterial wall. Arteries are composed of three major layers, i.e., the laminae intima, media, and adventitia. However, each of these layers may play different roles in arterial wall biology and atherogenesis. We identified well-structured artery tertiary lymphoid organs (ATLOs) in the abdominal aorta adventitia but not in the intima of aged apolipoprotein E-null (ApoE(-/-)) mice. These observations suggested that disease-associated immune responses are highly territorialized within the arterial wall and that the adventitia may play distinct and hitherto unrecognized roles. Here, we set out to apply laser capture microdissection (LCM) to dissect plaque, media, adventitia, and adjacent aorta-draining lymph nodes (LN) in aged ApoE(-/-) mice in attempts to establish the territoriality of atherosclerosis immune responses. Using whole-genome mRNA expression microarrays of arterial wall tissues, we constructed robust transcript atlases of wild-type and ApoE(-/-) mouse aortas. Data were deposited in the National Center for Biotechnology Information's gene expression omnibus (GEO) and are accessible to the public through the Internet. These transcript atlases are anticipated to prove valuable to address a wide scope of issues ranging from atherosclerosis immunity and inflammation to the role of single genes in regulating arterial wall remodeling. This chapter presents protocols for LCM of mouse aorta and microarray expression analysis from LCM-isolated aorta laminae.

  11. Peritoneal delivery of sodium pyrophosphate blocks the progression of pre-existing vascular calcification in uremic apolipoprotein-E knockout mice.

    PubMed

    de Oliveira, Rodrigo B; Louvet, Loïc; Riser, Bruce L; Barreto, Fellype C; Benchitrit, Joyce; Rezg, Raja; Poirot, Sabrina; Jorgetti, Vanda; Drüeke, Tilman B; Massy, Ziad A

    2015-08-01

    Chronic kidney disease (CKD) is generally associated with disturbances of mineral and bone metabolism. They contribute to the development of vascular calcification (VC), a strong, independent predictor of cardiovascular risk. Pyrophosphate (PPi), an endogenous inhibitor of hydroxyapatite formation, has been shown to slow the progression of VC in uremic animals. Since in patients with CKD treatment is usually initiated for already existing calcifications, we aimed to compare the efficacy of PPi therapy with that of the phosphate binder sevelamer, using a uremic apolipoprotein-E knockout mouse model with advanced VCs. After CKD creation or sham surgery, 12-week-old female mice were randomized to one sham group and four CKD groups (n = 18-19/group). Treatment was initiated 8 weeks after left nephrectomy allowing prior VC development. Uremic groups received either intraperitoneal PPi (high dose, 1.65 mg/kg or low dose, 0.33 mg/kg per day), oral sevelamer (3 % in diet), or placebo treatment for 8 weeks. Both intima and media calcifications worsened with time in placebo-treated CKD mice, based on both quantitative image analysis and biochemical measurements. Progression of calcification between 8 and 16 weeks was entirely halted by PPi treatment, as it was by sevelamer treatment. PPi did not induce consistent bone histomorphometry changes. Finally, the beneficial vascular action of PPi probably involved mechanisms different from that of sevelamer. Further studies are needed to gain more precise insight into underlying mechanisms and to see whether PPi administration may also be useful in patients with CKD and VC.

  12. Quantitative Trait Loci Affecting Atherosclerosis at the Aortic Root Identified in an Intercross between DBA2J and 129S6 Apolipoprotein E-Null Mice

    PubMed Central

    Kayashima, Yukako; Tomita, Hirofumi; Zhilicheva, Svetlana; Kim, Shinja; Kim, Hyung-Suk; Bennett, Brian J.; Maeda, Nobuyo

    2014-01-01

    Apolipoprotein E-null mice on a DBA/2J genetic background (DBA-apoE) are highly susceptible to atherosclerosis in the aortic root area compared with those on a 129S6 background (129-apoE). To explore atherosclerosis-responsible genetic regions, we performed a quantitative trait locus (QTL) analysis using 172 male and 137 female F2 derived from an intercross between DBA-apoE and 129-apoE mice. A genome-wide scan identified two significant QTL for the size of lesions at the root: one is Ath44 on Chromosome (Chr) 1 at 158 Mb, and the other Ath45 on Chr 2 at 162 Mb. Ath44 co-localizes with but appears to be independent of a previously reported QTL, Ath1, while Ath45 is a novel QTL. DBA alleles of both Ath44 and Ath45 confer atherosclerosis-susceptibility. In addition, a QTL on Chr 14 at 73 Mb was found significant only in males, and 129 allele conferring susceptibility. Further analysis detected female-specific interactions between a second QTL on Chr 1 at 73 Mb and a QTL on Chr 3 at 21 Mb, and between Chr 7 at 84 Mb and Chr 12 at 77 Mb. These loci for the root atherosclerosis were independent of QTLs for plasma total cholesterol and QTLs for triglycerides, but a QTL for HDL (Chr 1 at 126 Mb) overlapped with the Ath44. Notably, haplotype analysis among 129S6, DBA/2J and C57BL/6 genomes and their gene expression data narrowed the candidate regions for Ath44 and Ath45 to less than 5 Mb intervals where multiple genome wide associations with cardiovascular phenotypes have also been reported in humans. SNPs in or near Fmo3, Sele and Selp for Ath44, and Lbp and Pkig for Ath45 were suggested for further investigation as potential candidates underlying the atherosclerosis susceptibility. PMID:24586312

  13. Quercetin attenuates high fat diet-induced atherosclerosis in apolipoprotein E knockout mice: A critical role of NADPH oxidase.

    PubMed

    Xiao, Lin; Liu, Liang; Guo, Xiaoping; Zhang, Shanshan; Wang, Jing; Zhou, Feng; Liu, Liegang; Tang, Yuhan; Yao, Ping

    2017-07-01

    Reactive oxygen species (ROS) have emerged as important molecules in cardiovascular function. Nicotinamide-adenine dinucleotide phosphate (NADPH) oxidase is the major source of ROS in phagocytic and vascular cells. Several lines of evidence indicate that quercetin contributes to protecting against atherosclerosis. Herein, we investigated the effect of quercetin on alleviating atherosclerosis by regulating NADPH oxidase subunits expression in vivo, and explored the mechanism of quercetin suppressing the ROS overproduction stimulated by ox-LDL in mouse peritoneal macrophages (MPMs). Model ApoE KO mice were fed with either a normal chow diet or a high fat diet (HFD) supplemented with or without dosed quercetin for 24 weeks. Quercetin significantly reduced the atherosclerotic plaque area, alleviated the systemic oxidative stress, and suppressed aortic p47phox, p67phox expressions but partially reversed the NOX4 expression as compared to those in the HFD group. In vitro, quercetin effectively inhibited the ox-LDL induced ROS formation in MPMs, and blocked the vital step in activation of NADPH oxidase - membrane translocation of p47phox. Our findings suggest that regular consumption of dietary quercetin plays a role in preventing atherosclerosis giving its evident regulatory effect on subunits of NADPH oxidase. Copyright © 2017. Published by Elsevier Ltd.

  14. Attenuation of apoptosis by telmisartan in atherosclerotic plaques of apolipoprotein E-/- mice: evaluation using technetium 99m-annexin A5.

    PubMed

    Zhao, Yan; Zhao, Songji; Kuge, Yuji; Strauss, H William; Blankenberg, Francis G; Tamaki, Nagara

    2013-01-01

    Technetium 99m (99mTc)-annexin A5, a marker of ongoing apoptosis, is supposed to be useful in the detection of metabolically active atheroma. The aim of this study was to determine the potential of 99mTc-annexin A5 for evaluating the therapeutic effects of an angiotensin II receptor type 1 blocker (ARB) (telmisartan) on atherosclerosis. Male apolipoprotein E-/- mice were divided into telmisartan-treated (3 mg/kg/d, n  =  10) and control (n  =  10) groups. After 16 to 21 weeks of treatment, 99mTc-annexin A5 was injected and cryostat sections of aortic tissues (n  =  10-12/aorta) were prepared. The 99mTc-annexin A5 accumulation level in the plaques was evaluated by autoradiography. Serial sections of the plaques were histologically examined to identify the lesion phenotypes (normal vessels, early lesions, atheromatous lesions, and fibrotic lesions), plaque size, macrophage infiltration levels, and lipid deposition levels. Telmisartan treatment significantly decreased the plaque size (0.05 ± 0.05 vs 0.11 ± 0.08, mm2), macrophage infiltration level (0.02 ± 0.02 vs 0.03 ± 0.02, mm2), lipid deposition level (0.01 ± 0.01 vs 0.02 ± 0.02, mm2), and 99mTc-annexin A5 accumulation level (1.30 ± 1.09 vs 2.15 ± 1.91, × 10-6/g). 99mTc-annexin A5 accumulation levels in the plaques positively correlated with macrophage infiltration (r  =  .69, p < .05) and lipid deposition (r  =  .66, p < .05) levels. Apoptosis imaging with 99mTc-annexin A5 may be useful for evaluating the therapeutic effects of ARBs on atherosclerosis.

  15. Low-density lipoprotein receptor-mediated delivery of a lipophilic daunorubicin derivative to B16 tumours in mice using apolipoprotein E-enriched liposomes.

    PubMed Central

    Versluis, A. J.; Rensen, P. C.; Rump, E. T.; Van Berkel, T. J.; Bijsterbosch, M. K.

    1998-01-01

    Many tumours express relatively high levels of low-density lipoprotein (LDL) receptors on their membranes. The LDL receptor is, therefore, an attractive target for the selective delivery of antineoplastic drugs to tumour cells. We reported previously on the synthesis of small apolipoprotein E (apoE)-containing liposomes that behave in vivo in a very similar way to native LDL. In this study, we examined the interaction of this liposomal carrier with cultured B16 melanoma cells. Binding of apoE liposomes to the cells is saturable, with a maximum binding of approximately 90000 particles per cell. Cross-competition studies indicated that apoE liposomes are bound by the LDL receptor. Association of apoE liposomes to B16 cells is strictly Ca2+ dependent, which forms additional evidence for a role of the LDL receptor. The affinity of apoE liposomes for the LDL receptor on B16 cells is 15-fold higher than that of LDL (0.77 vs 11.5 nM respectively). ApoE is essential for the LDL receptor recognition because liposomes lacking apoE were, in competition studies, 20- to 50-fold less effective than apoE-containing liposomes. We examined in B16 tumour-bearing mice the tumour-localizing properties of apoE liposomes and the disposition of an incorporated lipophilic derivative of daunorubicin (LAD). Tissue distribution studies showed that LAD-loaded apoE liposomes were taken up and processed by the major LDL receptor-expressing organs (i.e. adrenals, liver and spleen). Of all other tissues, the tumour showed the highest uptake. The distribution patterns of LAD-loaded apoE liposomes and native LDL in the tumour-bearing mice were very similar, which supports the role of the LDL receptor in the disposition of the prodrug-loaded particles. The disposition of LAD followed the pattern of the liposomal carrier. We conclude that apoE liposomes enable LDL receptor-mediated specific delivery of antineoplastic (pro)drugs to tumours, and, therefore, constitute an attractive novel option for

  16. Proteomic Analysis of Mitochondria-Enriched Fraction Isolated from the Frontal Cortex and Hippocampus of Apolipoprotein E Knockout Mice Treated with Alda-1, an Activator of Mitochondrial Aldehyde Dehydrogenase (ALDH2).

    PubMed

    Stachowicz, Aneta; Olszanecki, Rafał; Suski, Maciej; Głombik, Katarzyna; Basta-Kaim, Agnieszka; Adamek, Dariusz; Korbut, Ryszard

    2017-02-17

    The role of different genotypes of apolipoprotein E (apoE) in the etiology of Alzheimer's disease is widely recognized. It has been shown that altered functioning of apoE may promote 4-hydroxynonenal modification of mitochondrial proteins, which may result in mitochondrial dysfunction, aggravation of oxidative stress, and neurodegeneration. Mitochondrial aldehyde dehydrogenase (ALDH2) is an enzyme considered to perform protective function in mitochondria by the detoxification of the end products of lipid peroxidation, such as 4-hydroxynonenal and other reactive aldehydes. The goal of our study was to apply a differential proteomics approach in concert with molecular and morphological techniques to elucidate the changes in the frontal cortex and hippocampus of apolipoprotein E knockout (apoE(-/-)) mice upon treatment with Alda-1-a small molecular weight activator of ALDH2. Despite the lack of significant morphological changes in the brain of apoE(-/-) mice as compared to age-matched wild type animals, the proteomic and molecular approach revealed many changes in the expression of genes and proteins, indicating the impairment of energy metabolism, neuroplasticity, and neurogenesis in brains of apoE(-/-) mice. Importantly, prolonged treatment of apoE(-/-) mice with Alda-1 led to the beneficial changes in the expression of genes and proteins related to neuroplasticity and mitochondrial function. The pattern of alterations implies mitoprotective action of Alda-1, however, the accurate functional consequences of the revealed changes require further research.

  17. Proteomic Analysis of Mitochondria-Enriched Fraction Isolated from the Frontal Cortex and Hippocampus of Apolipoprotein E Knockout Mice Treated with Alda-1, an Activator of Mitochondrial Aldehyde Dehydrogenase (ALDH2)

    PubMed Central

    Stachowicz, Aneta; Olszanecki, Rafał; Suski, Maciej; Głombik, Katarzyna; Basta-Kaim, Agnieszka; Adamek, Dariusz; Korbut, Ryszard

    2017-01-01

    The role of different genotypes of apolipoprotein E (apoE) in the etiology of Alzheimer’s disease is widely recognized. It has been shown that altered functioning of apoE may promote 4-hydroxynonenal modification of mitochondrial proteins, which may result in mitochondrial dysfunction, aggravation of oxidative stress, and neurodegeneration. Mitochondrial aldehyde dehydrogenase (ALDH2) is an enzyme considered to perform protective function in mitochondria by the detoxification of the end products of lipid peroxidation, such as 4-hydroxynonenal and other reactive aldehydes. The goal of our study was to apply a differential proteomics approach in concert with molecular and morphological techniques to elucidate the changes in the frontal cortex and hippocampus of apolipoprotein E knockout (apoE−/−) mice upon treatment with Alda-1—a small molecular weight activator of ALDH2. Despite the lack of significant morphological changes in the brain of apoE−/− mice as compared to age-matched wild type animals, the proteomic and molecular approach revealed many changes in the expression of genes and proteins, indicating the impairment of energy metabolism, neuroplasticity, and neurogenesis in brains of apoE−/− mice. Importantly, prolonged treatment of apoE−/− mice with Alda-1 led to the beneficial changes in the expression of genes and proteins related to neuroplasticity and mitochondrial function. The pattern of alterations implies mitoprotective action of Alda-1, however, the accurate functional consequences of the revealed changes require further research. PMID:28218653

  18. Apolipoprotein E genotype in schizophrenia

    SciTech Connect

    Joober, R.; Lal, S.; Bloom, D.; Benkelfat, C.

    1996-04-09

    We investigated the association between schizophrenia and the allelic polymorphism in the apolipoprotein E (Apo E) gene in 51 schizophrenic patients and 35 controls. The Apo E4 allele was equally represented in the schizophrenic group (16%) and the control group (20%) suggesting no association between schizophrenia and the Apo E4 allele. The apolipoprotein E (Apo E) is a polymorphic (E2, E3, and E4) lipoprotein involved in the transmembrane transport of cholesterol and is thought to play an important role in neuronal growth and in the central nervous system response to injury, particularly in the hippocampal region. Recent findings strongly suggest that the Apo E4 allele is associated with cognitive deficits in normal and pathological aging, e.g., Alzheimer`s disease. 5 refs., 1 tab.

  19. Apolipoprotein E promotes lipid accumulation and differentiation in human adipocytes

    SciTech Connect

    Lasrich, Dorothee; Bartelt, Alexander; Grewal, Thomas; Heeren, Joerg

    2015-09-10

    Several studies in mice indicate a role for apolipoprotein E (APOE) in lipid accumulation and adipogenic differentiation in adipose tissue. However, little is yet known if APOE functions in a similar manner in human adipocytes. This prompted us to compare lipid loading and expression of adipocyte differentiation markers in APOE-deficient and control adipocytes using the differentiated human mesenchymal stem cell line hMSC-Tert as well as primary human and mouse adipocytes as model systems. Differentiated hMSC-Tert were stably transduced with or without siRNA targeting APOE while murine adipocytes were isolated from wild type and Apoe knockout mice. Human APOE knockdown hMSC-Tert adipocytes accumulated markedly less triglycerides compared to control cells. This correlated with strongly decreased gene expression levels of adipocyte markers such as adiponectin (ADIPOQ) and fatty acid binding protein 4 (FABP4) as well as the key transcription factor driving adipocyte differentiation, peroxisome proliferator activator receptor gamma (PPARG), in particular the PPARG2 isoform. Similarly, differentiation of murine Apoe-deficient adipocytes was characterized by reduced gene expression of Adipoq, Fabp4 and Pparg. Interestingly, incubation of APOE-deficient hMSC-Tert adipocytes with conditioned media from APOE3-overexpressing adipocytes or APOE-containing Very Low Density Lipoprotein (VLDL) partially restored triglyceride accumulation, but were unable to induce adipocyte differentiation, as judged by expression of adipocyte markers. Taken together, depletion of endogenous APOE in human adipocytes severely impairs lipid accumulation, which is associated with an inability to initiate differentiation. - Highlights: • Immortalized human mesenchymal stem cells were used to study adipocyte development. • Knockdown of endogenous APOE lead to impaired lipid accumulation and adipogenesis. • APOE supplementation partially restored lipid accumulation but not differentiation.

  20. Apolipoprotein E and its role in aging and survival.

    PubMed

    Bonomini, Francesca; Filippini, Francesca; Hayek, Tony; Aviram, Michael; Keidar, Shlomo; Rodella, Luigi F; Coleman, Raymond; Rezzani, Rita

    2010-02-01

    The study of biological aging has seen spectacular progress in the last decade and markers are increasingly employed for understanding physiological processes that change with age. Recently, it has been demonstrated that apolipoprotein E (apoE) has a major impact on longevity, but its mechanisms are still not fully understood. ApoE-deficient (E(o)) mice have proved to be a very popular model for studying spontaneous hypercholesterolemia and the subsequent development of atherosclerotic lesions, but only limited data are available with regard to aging and aging changes. We used this murine model to better characterize the involvement of apoE in aging and to evaluate its role in the maintenance of normal organ morphology. Our results show that E(0) mice at different ages (6, 12, 20 weeks old) developed age-dependent morphological and biochemical alterations, including fibrosis (newly formed collagen), pro-inflammatory cytokine (IL-6 and iNOS), lipofuscin accumulation, and decrease of antioxidant enzymes (superoxide dismutase and catalase) in several organs (kidney, liver and heart). It is significant that the observed degenerative findings in E(0) mice at different ages (6, 12, 20 weeks old) were not identified in control mice (C57BL), at 6, 12 and 20 weeks of age. Consequently, since these mice showed enzymatic and structural alterations, normally linked to the age, such as increase of lipofuscin, pro-inflammatory cytokines and decrease of antioxidant enzymes, we can conclude that apoE is a useful player in studies of longevity and age-related diseases, such as inflammatory status and atherosclerosis that are known risk factors for functional decline and early mortality. Moreover, it is possible that apoE may also play a role in other pathological conditions including, for example, cancer, rheumatoid arthritis and macular degeneration.

  1. Association between ε2/3/4, promoter polymorphism (-491A/T, -427T/C, and -219T/G) at the apolipoprotein E gene, and mental retardation in children from an iodine deficiency area, China.

    PubMed

    Li, Jun; Zhang, Fuchang; Wang, Yunliang; Wang, Yan; Qin, Wei; Xing, Qinghe; Qian, Xueqing; Guo, Tingwei; Gao, Xiaocai; He, Lin; Gao, Jianjun

    2014-01-01

    Several common single-nucleotide polymorphisms (SNPs) at apolipoprotein E (ApoE) have been linked with late onset sporadic Alzheimer's disease and declining normative cognitive ability in elder people, but we are unclear about their relationship with cognition in children. We studied -491A/T, -427T/C, and -219G/T promoter polymorphisms and ε2/ε3/ε4 at ApoE among children with mental retardation (MR, n = 130), borderline MR (n = 124), and controls (n = 334) from an iodine deficiency area in China. The allelic and genotypic distribution of individual locus did not significantly differ among three groups with Mantel-Haenszel χ (2) test (P > 0.05). However, frequencies of haplotype of -491A/-427T/-219T/ε4 were distributed as MR > borderline MR > controls (P uncorrected = 0.004), indicating that the presence of this haplotype may increase the risk of disease. In this large population-based study in children, we did not find any significant association between single locus of the four common ApoE polymorphisms (-491A/T, -427T/C, -219T/G, and ε2/3/4) and MR or borderline MR. However, we found that the presence of ATTε4 haplotype was associated with an increased risk of MR and borderline MR. Our present work may help enlarge our knowledge of the cognitive role of ApoE across the lifespan and the mechanisms of human cognition.

  2. Role of apolipoprotein E in febrile convulsion.

    PubMed

    Giray, Ozlem; Ulgenalp, Ayfer; Bora, Elçin; Uran, Nedret; Yilmaz, Ebru; Unalp, Aycan; Erçal, Derya

    2008-10-01

    Apolipoprotein E is consistently associated with the progression of some common human neurodegenerative diseases, e.g., epilepsy. We hypothesized that genetic variations in the apolipoprotein E gene have implications for susceptibility to, and prognoses in, febrile convulsion, which plays an apparent role in the development of epilepsy. We used the polymerase chain reaction and restriction enzyme digestion to characterize variations of the apolipoprotein E gene. Sixty-nine patients with febrile convulsion (simple/complex) and a corresponding cohort of healthy patients (n = 75) were used. There was no significant difference in genotypic distribution and allelic frequencies of the apolipoprotein E gene between the febrile convulsion and control groups. Comparing subpopulations of the febrile convulsion group (patients with simple and complex febrile convulsion), we noted that no patients with the epsilon3/epsilon4 genotype had complex febrile convulsions. The apolipoprotein E epsilon3/epsilon4 genotype was more frequently seen in the simple febrile than in the complicated febrile convulsion group (9 versus 0 patients, respectively). The data indicate an association with the epsilon3/epsilon4 genotype of the apolipoprotein E gene with a milder phenotype. Although apolipoprotein E4 is not a vulnerability factor regarding febrile convulsions, it seems effective in regard to prognoses.

  3. Specific binding and uptake of apolipoprotein E-free high density lipoproteins (apo E-free HDL) by cultured liver parenchymal cells of copper-deficient rats

    SciTech Connect

    Zhang, J.; Carr, T.P.; Lei, K.Y. )

    1989-02-09

    Weanling male Sprague-Dawley rats were assigned to two dietary treatments; copper-deficient (CD, 1.0 ppm) and adequate (CA, 6.7 ppm). After 8 weeks, plasma apo E-free HDL were isolated by a combination of ultracentrifugation, gel filtration, and heparin-Sepharose affinity chromatography. Liver parenchymal cells obtained by collagenase perfusion and Percoll gradient centrifugation were cultured for 16 hr. Cells were then incubated with {sup 125}I-apo E-free HDL, either from the same treatment group or in a crossover design, in order to establish if treatment differences were associated with cells and/or lipoproteins. Cells were incubate with apo E-free HDL for 2, 6, 12, and 24 hr in the presence or absence of excess unlabeled apo E-free HDL. Binding studies at 4{degree}C indicated a small but significant increases in specific binding in CD cells regardless of the source of apo E-free HDL. In cell association studies at 37{degree}C, CD cells demonstrated similar marked increases of apo E-free HDL uptake from both treatment groups. The increase in uptake may be associated with an increased expression of HDL binding sites in CD cells. These findings are consistent with recent in vivo studies which indicate plasma clearance and tissue uptake of total HDL are increased in copper-deficient rats.

  4. Apolipoprotein E: the resilience gene.

    PubMed

    James, Lisa M; Engdahl, Brian E; Georgopoulos, Apostolos P

    2017-03-15

    The apolipoprotein E (apoE) gene has been implicated in various conditions, most notably Alzheimer's disease and coronary artery disease. A predisposing role of the apoE4 isoform and a protective role of apoE2 isoform in those diseases have been documented. Here we investigated the role of apoE in resilience to trauma. Three hundred and forty-three US veterans were genotyped for apoE and were assessed for their lifetime trauma exposure (trauma score, T) and severity of posttraumatic stress disorder symptoms (PCL). The ratio PCL/T indicates sensitivity to trauma; hence, its inverse indicates resilience, R, to trauma. We found a significantly higher resilience in participants with apoE genotype containing the E2 allele (E2/2, E2/3) as compared to participants with the E4 allele (E4/4, E4/3). In addition, when the categorical apoE genotype was reexpressed as the number of cysteine residues per apoE mole (CysR/mole), a highly significant positive association was found between resilience and CysR/mole, such that resilience was systematically higher as the number of CysR/mole increased, from zero CysR/mole in E4/4 to four CysR/mole in E2/2. These findings demonstrate the protective role of the CysR/mole apoE in resilience to trauma: the more CysR/mole, the higher the resilience. Thus, they are in accord with other findings pointing to a generally protective role of increasing number of CysR/mole (from E4/4 to E2/2) in other diseases. However, unlike other conditions (e.g., Alzheimer's disease and coronary artery disease), resilience to trauma is not a disease but an adaptive response to trauma. Therefore, the effects of apoE seem to be more pervasive along the CysR/mole continuum, most probably reflecting underlying effects on brain synchronicity and its variability that we have documented previously (Leuthold et al., Exp Brain Res 226:525-536, 2013).

  5. Critical role of peroxisome proliferator activated receptor-δ on body fat reduction in C57BL/6J and human apolipoprotein E2 transgenic mice fed delipidated soybean.

    PubMed

    Lee, Ji Hae; Jun, Hee-jin; Jia, Yaoyao; Kim, Wook; Choi, Sung-Gil; Lee, Sung-Joon

    2011-11-09

    The consumption of soy protein and fiber reduces body fat accumulation; however, the mechanism of this effect has not been clearly understood. We investigated the antiobesogenic effect of soy protein and fiber in two different mouse models. Normolipidemic nonobese C57BL/6J and hyperlipidemic obese human apolipoprotein E2 transgenic mice were fed either delipidated soybean (DLSB) containing soy protein and fiber or a control diet. The DLSB-fed mice showed a significant reduction in body weight gain and adiposity compared with controls, in both C57BL/6J and apoE2 mice. All metabolic parameters were significantly improved in the DLSB group compared with controls: total cholesterol, low-density lipoprotein cholesterol, insulin, and leptin levels were significantly reduced. Adiponectin concentrations were significantly elevated, and glucose tolerance was improved. In both types of DLSB-fed mice, the specific induction of PPAR-δ protein expression was evident in muscle and adipose tissues. The expression of PPAR-δ target genes in the DLSB-fed mice was also significantly altered. Acetyl-CoA carboxylase-1 and fatty acid synthase levels in adipose tissue were downregulated, and uncoupling protein-2 in muscle was upregulated. Intestinal expression of fatty acid transport protein-4, cluster of differentiation-36, and acyl-CoA synthetase were significantly downregulated. We propose that marked activation of PPAR-δ is the primary mechanism mediating the antiobesogenic effect of soybean and that PPAR-δ has multiple actions: induction of thermogenesis in muscle, reduction of fatty acid synthesis in adipose tissue, and reduction of fatty acid uptake in intestinal tissue.

  6. Combined Vitamin C and Vitamin E Deficiency Worsens Early Atherosclerosis in ApoE-Deficient Mice

    PubMed Central

    Babaev, Vladimir R.; Li, Liying; Shah, Sanket; Fazio, Sergio; Linton, MacRae F.; May, James M.

    2010-01-01

    Objective Atherosclerosis is an inflammatory condition associated with oxidative stress, but controversy persists regarding whether antioxidants such as vitamins C and E are preventative. To assess the role of combined deficiencies of vitamins C and E on the earliest stages of atherosclerosis, four combinations of vitamin supplementation (Low C/Low E, Low C/High E, High C/Low E, High C/High E) were studied in atherosclerosis-prone apolipoprotein E (apoE)-deficient mice also unable to synthesize their own vitamin C (gulo−/−). The effect of a more severe depletion of vitamin C alone was evaluated in a second experiment using gulo−/− mice carrying the hemizygous deletion of SVCT2, the vitamin C transporter. Methods and Results After 8 weeks on a high-fat diet (16% lard, 0.2% cholesterol), atherosclerosis developed in the aortic sinus areas of mice in all diet groups. Each vitamin-deficient diet significantly decreased liver and brain contents of the corresponding vitamin. Combined deficiency of both vitamins increased lipid peroxidation, doubled plaque size, and increased plaque macrophage content by 2-3-fold in males, although only plaque macrophage content was increased in females. A more severe deficiency of vitamin C in gulo−/− mice with defective cellular uptake of vitamin C increased both oxidative stress and atherosclerosis in apoE−/− mice compared to littermates on a diet replete in vitamin C, again most clearly in males. Conclusion Combined vitamin E and C deficiencies are required to worsen early atherosclerosis in an apoE-deficient mouse model. However, a more severe cellular deficiency of vitamin C alone promotes atherosclerosis when vitamin E is replete. PMID:20558818

  7. Delayed olfactory nerve regeneration in ApoE-deficient mice.

    PubMed

    Nathan, Britto P; Nisar, Rafia; Short, Jody; Randall, Shari; Grissom, Elin; Griffin, Gwen; Switzer, Paul V; Struble, Robert G

    2005-04-11

    Apolipoprotein E (apoE), a lipid transporting protein, is extensively expressed in the primary olfactory pathway, but its function is unknown. We previously reported increased apoE levels in the olfactory bulb (OB) following olfactory epithelium (OE) lesion in mice, and hypothesized that apoE may play a vital role in olfactory nerve (ON) regeneration. To directly test this hypothesis, we examined the rate of ON regeneration following OE lesion in apoE deficient/knockout (KO) and wild-type (WT) mice. OE was lesioned in 2- to 3-month-old mice by intranasal irrigation with Triton X-100 (TX). OB were collected at 0, 3, 7, 21, 42, and 56 days post-lesion. OB recovery was measured by both immunoblotting and immunohistochemical analysis of growth cone associated protein (GAP) 43 and olfactory marker protein (OMP). The results revealed that (1) OMP recovery in the OB was significantly slower in apoE KO compared to WT mice; (2) recovery of glomerular area was similarly slower; and (3) GAP43 increases and return to prelesion levels in the OB were slower in KO mice. Together, these results show that olfactory nerve regeneration is significantly slower in KO mice as compared to WT mice, suggesting apoE facilitates olfactory nerve regeneration.

  8. Selective deletion of apolipoprotein E in astrocytes ameliorates the spatial learning and memory deficits in Alzheimer's disease (APP/PS1) mice by inhibiting TGF-β/Smad2/STAT3 signaling.

    PubMed

    Zheng, Jin-Yu; Sun, Jian; Ji, Chun-Mei; Shen, Lin; Chen, Zhong-Jun; Xie, Peng; Sun, Yuan-Zhao; Yu, Ru-Tong

    2017-06-01

    Astrocytes and apolipoprotein E (apoE) play critical roles in cognitive function, not only under physiological conditions but also in some pathological situations, particularly in the pathological progression of Alzheimer's disease (AD). The regulatory mechanisms underlying the effect of apoE, derived from astrocytes, on cognitive deficits during AD pathology development are unclear. In this study, we generated amyloid precursor protein/apoE knockout (APP/apoE(KO)) and APP/glial fibrillary acidic protein (GFAP)-apoE(KO) mice (the AD mice model used in this study was based on the APP-familial Alzheimer disease overexpression) to investigate the role of apoE, derived from astrocytes, in AD pathology and cognitive function. To explore the mechanism, we investigated the amyloidogenic process related transforming growth factor β/mothers against decapentaplegic homolog 2/signal transducer and activator of transcription 3 (TGF-β/Smad2/STAT3) signaling pathway and further confirmed by administering TGF-β-overexpression adeno-associated virus (specific to astrocytes) to APP/GFAP-apoE(KO) mice and TGF-β-inhibition adeno-associated virus (specific to astrocytes) to APP/WT mice. Whole body deletion of apoE significantly ameliorated the spatial learning and memory impairment, reduced amyloid β-protein production and inhibited astrogliosis in APP/apoE(KO) mice, as well as specific deletion apoE in astrocytes in APP/GFAP-apoE(KO) mice. Moreover, amyloid β-protein accumulation was increased due to promotion of amyloidogenesis of APP, and astrogliosis was upregulated by activation of TGF-β/Smad2/STAT3 signaling. Furthermore, the overexpression of TGF-β in astrocytes in APP/GFAP-apoE(KO) mice abrogated the effects of apoE knockout. In contrast, repression of TGF-β in astrocytes of APP/WT mice exerted a therapeutic effect similar to apoE knockout. These data suggested that apoE derived from astrocytes contributes to the risk of AD through TGF-β/Smad2/STAT3 signaling

  9. Apolipoprotein E4 causes age- and sex-dependent impairments of hilar GABAergic interneurons and learning and memory deficits in mice.

    PubMed

    Leung, Laura; Andrews-Zwilling, Yaisa; Yoon, Seo Yeon; Jain, Sachi; Ring, Karen; Dai, Jessica; Wang, Max Mu; Tong, Leslie; Walker, David; Huang, Yadong

    2012-01-01

    Apolipoprotein (apo) E4 is the major genetic risk factor for Alzheimer's disease (AD). ApoE4 has sex-dependent effects, whereby the risk of developing AD is higher in apoE4-expressing females than males. However, the mechanism underlying the sex difference, in relation to apoE4, is unknown. Previous findings indicate that apoE4 causes age-dependent impairments of hilar GABAergic interneurons in female mice, leading to learning and memory deficits. Here, we investigate whether the detrimental effects of apoE4 on hilar GABAergic interneurons are sex-dependent using apoE knock-in (KI) mice across different ages. We found that in female apoE-KI mice, there was an age-dependent depletion of hilar GABAergic interneurons, whereby GAD67- or somatostatin-positive--but not NPY- or parvalbumin-positive-interneuron loss was exacerbated by apoE4. Loss of these neuronal populations was correlated with the severity of spatial learning deficits at 16 months of age in female apoE4-KI mice; however, this effect was not observed in female apoE3-KI mice. In contrast, we found an increase in the numbers of hilar GABAergic interneurons with advancing age in male apoE-KI mice, regardless of apoE genotype. Moreover, male apoE-KI mice showed a consistent ratio of hilar inhibitory GABAergic interneurons to excitatory mossy cells approximating 1.5 that is independent of apoE genotype and age, whereas female apoE-KI mice exhibited an age-dependent decrease in this ratio, which was exacerbated by apoE4. Interestingly, there are no apoE genotype effects on GABAergic interneurons in the CA1 and CA3 subregions of the hippocampus as well as the entorhinal and auditory cortexes. These findings suggest that the sex-dependent effects of apoE4 on developing AD is in part attributable to inherent sex-based differences in the numbers of hilar GABAergic interneurons, which is further modulated by apoE genotype.

  10. Relationship between hemodynamics and atherosclerosis in aortic arches of apolipoprotein E-null mice on 129S6/SvEvTac and C57BL/6J genetic backgrounds

    PubMed Central

    Tomita, Hirofumi; Hagaman, John; Friedman, Morton H.; Maeda, Nobuyo

    2011-01-01

    Objective We investigated the relationships between hemodynamics and differential plaque development at the aortic arch of apolipoprotein E (apoE)-null mice on 129S6/SvEvTac (129) and C57BL/6J (B6) genetic backgrounds. Methods Mean flow velocities at the ascending and descending aorta (mVAA and mVDA) were measured by Doppler ultrasound in wild type and apoE-null male mice at 3 and 9 months of age. Following dissection of the aortic arches, anatomical parameters and plaque areas were evaluated. Results Arch plaques were five times bigger in 129-apoE than in B6-apoE mice at 3 months, and twice as large at 9 months. The geometric differences, namely larger vessel diameter in the B6 strain and broader inner curvature of the aortic arch in the 129 strain, were exaggerated in 9-month-old apoE-null mice. Cardiac output and heart rate under anesthesia were significantly higher in the B6 strain than in the 129 strain. The values of mVAA were similar in the two strains, while mVDA was lower in the 129 strain. However, there was a 129-apoE-specific reduction of flow velocities with age, and both mVAA and mVDA were significantly lower in 129-apoE than in B6-apoE mice at 9 months. The mean relative wall shear stress (rWSS) over the aortic arch in 129-apoE and B6-apoE mice were not different, but animals with lower mean rWSS had larger arch plaques within each strain. Conclusions The plaque formation in the arch of apoE-null mice is accompanied by strain-dependent changes in both arch geometry and hemodynamics. While arch plaque sizes negatively correlate with mean rWSS, additional factors are necessary to account for the strain differences in arch plaque development. PMID:22078246

  11. A selective ACAT-1 inhibitor, K-604, stimulates collagen production in cultured smooth muscle cells and alters plaque phenotype in apolipoprotein E-knockout mice.

    PubMed

    Yoshinaka, Yasunobu; Shibata, Haruki; Kobayashi, Hideyuki; Kuriyama, Hiroki; Shibuya, Kimiyuki; Tanabe, Sohei; Watanabe, Takuya; Miyazaki, Akira

    2010-11-01

    Acyl-coenzyme A:cholesterol O-acyltransferase-1 (ACAT-1) plays an essential role in macrophage foam cell formation and progression of atherosclerosis. We developed a potent and selective ACAT-1 inhibitor, K-604, and tested its effects in apoE-knockout mice. Administration of K-604 to 8-week-old apoE-knockout mice for 12 weeks at a dose of 60 mg/kg/day significantly reduced macrophage-positive area and increased collagen-positive area in atherosclerotic plaques in the aorta without affecting plasma cholesterol levels or lesion areas, indicating direct plaque-modulating effects of K-604 on vascular walls independent of plasma cholesterol levels. Pactimibe, a nonselective inhibitor of ACAT-1 and ACAT-2, reduced plasma cholesterol levels but did not affect macrophage- or collagen-positive areas. The size of macrophages and cholesteryl ester contents in the aorta were reduced by K-604. Exposure of cultured human aortic smooth muscle cells to K-604 resulted in increased procollagen type 1 contents in the culture supernatant and increased procollagen type 1 mRNA levels. Procollagen production was unaffected by pactimibe even at a concentration that inhibited cholesterol esterification to the basal level. Thus, the plaque-modulating effects of K-604 can be explained by stimulation of procollagen production independent of ACAT inhibition in addition to potent inhibition of macrophage ACAT-1.

  12. Attrition of Hepatic Damage Inflicted by Angiotensin II with α-Tocopherol and β-Carotene in Experimental Apolipoprotein E Knock-out Mice.

    PubMed

    Gopal, Kaliappan; Gowtham, Munusamy; Sachin, Singh; Ravishankar Ram, Mani; Shankar, Esaki M; Kamarul, Tunku

    2015-12-16

    Angiotensin II is one of the key regulatory peptides implicated in the pathogenesis of liver disease. The mechanisms underlying the salubrious role of α-tocopherol and β-carotene on liver pathology have not been comprehensively assessed. Here, we investigated the mechanisms underlying the role of Angiotensin II on hepatic damage and if α-tocopherol and β-carotene supplementation attenuates hepatic damage. Hepatic damage was induced in Apoe(-/-)mice by infusion of Angiotensin II followed by oral administration with α-tocopherol and β-carotene-enriched diet for 60 days. Investigations showed fibrosis, kupffer cell hyperplasia, hepatocyte degeneration and hepatic cell apoptosis; sinusoidal dilatation along with haemorrhages; evidence of fluid accumulation; increased ROS level and increased AST and ALT activities. In addition, tPA and uPA were down-regulated due to 42-fold up-regulation of PAI-1. MMP-2, MMP-9, MMP-12, and M-CSF were down-regulated in Angiotensin II-treated animals. Notably, α-tocopherol and β-carotene treatment controlled ROS, fibrosis, hepatocyte degeneration, kupffer cell hyperplasia, hepatocyte apoptosis, sinusoidal dilatation and fluid accumulation in the liver sinusoids, and liver enzyme levels. In addition, PAI-1, tPA and uPA expressions were markedly controlled by β-carotene treatment. Thus, Angiotensin II markedly influenced hepatic damage possibly by restraining fibrinolytic system. We concluded that α-tocopherol and β-carotene treatment has salubrious role in repairing hepatic pathology.

  13. Apolipoprotein E4 and Insulin Resistance Interact to Impair Cognition and Alter the Epigenome and Metabolome

    PubMed Central

    Johnson, Lance A.; Torres, Eileen Ruth S.; Impey, Soren; Stevens, Jan F.; Raber, Jacob

    2017-01-01

    Apolipoprotein E4 (E4) and type 2 diabetes are major risk factors for cognitive decline and late onset Alzheimer’s disease (AD). E4-associated phenotypes and insulin resistance (IR) share several features and appear to interact in driving cognitive dysfunction. However, shared mechanisms that could explain their overlapping pathophysiology have yet to be found. We hypothesized that, compared to E3 mice, E4 mice would be more susceptible to the harmful cognitive effects of high fat diet (HFD)-induced IR due to apoE isoform-specific differences in brain metabolism. While both E3 and E4 mice fed HFD displayed impairments in peripheral metabolism and cognition, deficits in hippocampal-dependent spatial learning and memory were exaggerated in E4 mice. Combining genome-wide measures of DNA hydroxymethylation with comprehensive untargeted metabolomics, we identified novel alterations in purine metabolism, glutamate metabolism, and the pentose phosphate pathway. Finally, in E4 mice, the metabolic and cognitive deficiencies caused by HFD were rescued by switching to a low fat diet for one month, suggesting a functional role was associated with reversal of the same metabolic pathways described above. These results suggest a susceptibility of E4 carriers to metabolic impairments brought on by IR, and may guide development of novel therapies for cognitive decline and dementia. PMID:28272510

  14. Apolipoprotein E Polymorphism in Tuberculosis Patients

    NASA Astrophysics Data System (ADS)

    Naserpour Farivar, Taghi; Sharifi Moud, Batool; Sargazi, Mansur; Moeenrezakhanlou, Alireza

    In this study, we aimed to determine the significance of association between Tuberculosis and apolipoprotein E polymorphism. The apolipoprotein E genotypes were assayed in 250 tuberculosis patients by polymerase chain reaction followed by enzymatic digestion with Hha I. The results were compared with the results of the same experiments on 250 sex and age matched control peoples. Present results showed that in studied populations, prevalence of E4 genotype was lower in controls than in patients (8 v. 13.2%; OR = 1.75, p<0.05) and prevalence of E3 genotype was high in controls than in patients (86 v.51%; OR = 0.17, p<0.05). Statistically significant difference was found between patients and controls with respect to ɛ2 allele frequencies, while ɛ2 allele frequency was found to be much less prevalent in controls (6%) than in patients (35.8%; OR = 8.72, p<0.05). Also, our study revealed that there is an association between apolipoprotein E genotypes and amplitude to tuberculosis in studied populations. However, large population-based studies are needed to understand the exact role played by the locus in causing the condition.

  15. Direct Transcriptional Effects of Apolipoprotein E

    PubMed Central

    Theendakara, Veena; Peters-Libeu, Clare A.; Spilman, Patricia; Poksay, Karen S.

    2016-01-01

    A major unanswered question in biology and medicine is the mechanism by which the product of the apolipoprotein E ε4 allele, the lipid-binding protein apolipoprotein E4 (ApoE4), plays a pivotal role in processes as disparate as Alzheimer's disease (AD; in which it is the single most important genetic risk factor), atherosclerotic cardiovascular disease, Lewy body dementia, hominid evolution, and inflammation. Using a combination of neural cell lines, skin fibroblasts from AD patients, and ApoE targeted replacement mouse brains, we show in the present report that ApoE4 undergoes nuclear translocation, binds double-stranded DNA with high affinity (low nanomolar), and functions as a transcription factor. Using chromatin immunoprecipitation and high-throughput DNA sequencing, our results indicate that the ApoE4 DNA binding sites include ∼1700 gene promoter regions. The genes associated with these promoters provide new insight into the mechanism by which AD risk is conferred by ApoE4, because they include genes associated with trophic support, programmed cell death, microtubule disassembly, synaptic function, aging, and insulin resistance, all processes that have been implicated in AD pathogenesis. SIGNIFICANCE STATEMENT This study shows for the first time that apolipoprotein E4 binds DNA with high affinity and that its binding sites include 1700 promoter regions that include genes associated with neurotrophins, programmed cell death, synaptic function, sirtuins and aging, and insulin resistance, all processes that have been implicated in Alzheimer's disease pathogenesis. PMID:26791201

  16. Deficiency in lymphotoxin β receptor protects from atherosclerosis in apoE-deficient mice.

    PubMed

    Grandoch, Maria; Feldmann, Kathrin; Göthert, Joachim R; Dick, Lena S; Homann, Susanne; Klatt, Christina; Bayer, Julia K; Waldheim, Jan N; Rabausch, Berit; Nagy, Nadine; Oberhuber, Alexander; Deenen, René; Köhrer, Karl; Lehr, Stefan; Homey, Bernhard; Pfeffer, Klaus; Fischer, Jens W

    2015-04-10

    Lymphotoxin β receptor (LTbR) regulates immune cell trafficking and communication in inflammatory diseases. However, the role of LTbR in atherosclerosis is still unclear. The aim of this study was to elucidate the role of LTbR in atherosclerosis. After 15 weeks of feeding a Western-type diet, mice double-deficient in apolipoprotein E and LTbR (apoE(-/-)/LTbR(-/-)) exhibited lower aortic plaque burden than did apoE(-/-) littermates. Macrophage content at the aortic root and in the aorta was reduced, as determined by immunohistochemistry and flow cytometry. In line with a decrease in plaque inflammation, chemokine (C-C motif) ligand 5 (Ccl5) and other chemokines were transcriptionally downregulated in aortic tissue from apoE(-/-)/LTbR(-/-) mice. Moreover, bone marrow chimeras demonstrated that LTbR deficiency in hematopoietic cells mediated the atheroprotection. Furthermore, during atheroprogression, apoE(-/-) mice exhibited increased concentrations of cytokines, for example, Ccl5, whereas apoE(-/-)/LTbR(-/-) mice did not. Despite this decreased plaque macrophage content, flow cytometric analysis showed that the numbers of circulating lymphocyte antigen 6C (Ly6C)(low) monocytes were markedly elevated in apoE(-/-)/LTbR(-/-) mice. The influx of these cells into atherosclerotic lesions was significantly reduced, whereas apoptosis and macrophage proliferation in atherosclerotic lesions were unaffected. Gene array analysis pointed to chemokine (C-C motif) receptor 5 as the most regulated pathway in isolated CD115(+) cells in apoE(-/-)/LTbR(-/-) mice. Furthermore, stimulating monocytes from apoE(-/-) mice with agonistic anti-LTbR antibody or the natural ligand lymphotoxin-α1β2, increased Ccl5 mRNA expression. These findings suggest that LTbR plays a role in macrophage-driven inflammation in atherosclerotic lesions, probably by augmenting the Ccl5-mediated recruitment of monocytes. © 2015 American Heart Association, Inc.

  17. Apolipoprotein E expression and behavioral toxicity of high charge, high energy (HZE) particle radiation

    NASA Technical Reports Server (NTRS)

    Higuchi, Yoshinori; Nelson, Gregory A.; Vazquez, Marcelo; Laskowitz, Daniel T.; Slater, James M.; Pearlstein, Robert D.

    2002-01-01

    Apolipoprotein E (apoE) is a lipid binding protein that plays an important role in tissue repair following brain injury. In the present studies, we have investigated whether apoE affects the behavioral toxicity of high charge, high energy (HZE) particle radiation. METHODS: Sixteen male apoE knockout (KO) mice and sixteen genetically matched wild-type (WT) C57BL mice were used in this experiment. Half of the KO and half of the WT animals were irradiated with 600 MeV/amu iron particles (2 Gy whole body). The effect of irradiation on motor coordination and stamina (Rotarod test), exploratory behavior (open field test), and spatial working and reference memory (Morris water maze) was assessed. ROTAROD TEST: Performance was adversely affected by radiation exposure in both KO and WT groups at 30 d after irradiation. By 60 d after radiation, the radiation effect was lost in WT, but still apparent in irradiated KO mice. OPEN FIELD TEST: Radiation reduced open field exploratory activity 14, 28, 56, 84, and 168 d after irradiation of KO mice, but had no effect on WT mice. MORRIS WATER MAZE: Radiation adversely affected spatial working memory in the KO mice, but had no discernible effect in the WT mice as assessed 180 d after irradiation. In contrast, irradiated WT mice showed marked impairment of spatial reference memory in comparison to non-irradiated mice, while no effect of radiation was observed in KO mice. CONCLUSIONS: These studies show that apoE expression influences the behavioral toxicity of HZE particle radiation and suggest that apoE plays a role in the repair/recovery from radiation injury of the CNS. ApoE deficiency may exacerbate the previously reported effects of HZE particle radiation in accelerating the brain aging process.

  18. Apolipoprotein E expression and behavioral toxicity of high charge, high energy (HZE) particle radiation

    NASA Technical Reports Server (NTRS)

    Higuchi, Yoshinori; Nelson, Gregory A.; Vazquez, Marcelo; Laskowitz, Daniel T.; Slater, James M.; Pearlstein, Robert D.

    2002-01-01

    Apolipoprotein E (apoE) is a lipid binding protein that plays an important role in tissue repair following brain injury. In the present studies, we have investigated whether apoE affects the behavioral toxicity of high charge, high energy (HZE) particle radiation. METHODS: Sixteen male apoE knockout (KO) mice and sixteen genetically matched wild-type (WT) C57BL mice were used in this experiment. Half of the KO and half of the WT animals were irradiated with 600 MeV/amu iron particles (2 Gy whole body). The effect of irradiation on motor coordination and stamina (Rotarod test), exploratory behavior (open field test), and spatial working and reference memory (Morris water maze) was assessed. ROTAROD TEST: Performance was adversely affected by radiation exposure in both KO and WT groups at 30 d after irradiation. By 60 d after radiation, the radiation effect was lost in WT, but still apparent in irradiated KO mice. OPEN FIELD TEST: Radiation reduced open field exploratory activity 14, 28, 56, 84, and 168 d after irradiation of KO mice, but had no effect on WT mice. MORRIS WATER MAZE: Radiation adversely affected spatial working memory in the KO mice, but had no discernible effect in the WT mice as assessed 180 d after irradiation. In contrast, irradiated WT mice showed marked impairment of spatial reference memory in comparison to non-irradiated mice, while no effect of radiation was observed in KO mice. CONCLUSIONS: These studies show that apoE expression influences the behavioral toxicity of HZE particle radiation and suggest that apoE plays a role in the repair/recovery from radiation injury of the CNS. ApoE deficiency may exacerbate the previously reported effects of HZE particle radiation in accelerating the brain aging process.

  19. Introduction of human apolipoprotein E4 "domain interaction" into mouse apolipoprotein E.

    PubMed

    Raffai, R L; Dong, L M; Farese, R V; Weisgraber, K H

    2001-09-25

    Human apolipoprotein E4 (apoE4) binds preferentially to lower density lipoproteins, including very low density lipoproteins, and is associated with increased risk of atherosclerosis and neurodegenerative disorders, including Alzheimer's disease. This binding preference is the result of the presence of Arg-112, which causes Arg-61 in the amino-terminal domain to interact with Glu-255 in the carboxyl-terminal domain. ApoE2 and apoE3, which have Cys-112, bind preferentially to high density lipoproteins (HDL) and do not display apoE4 domain interaction. Mouse apoE, like apoE4, contains the equivalent of Arg-112 and Glu-255, but lacks the critical Arg-61 equivalent (it contains Thr-61). Thus, mouse apoE does not display apoE4 domain interaction and, as a result, behaves like human apoE3, including preferential binding to HDL. To assess the potential role of apoE4 domain interaction in atherosclerosis and neurodegeneration, we sought to introduce apoE4 domain interaction into mouse apoE. Replacing Thr-61 in mouse apoE with arginine converted the binding preference from HDL to very low density lipoproteins in vitro, suggesting that apoE4 domain interaction could be introduced into mouse apoE in vivo. Using gene targeting in embryonic stem cells, we created mice expressing Arg-61 apoE. Heterozygous Arg-61/wild-type apoE mice displayed two phenotypes found in human apoE4/E3 heterozygotes: preferential binding to lower density lipoproteins and reduced abundance of Arg-61 apoE in the plasma, reflecting its more rapid catabolism. These findings demonstrate the successful introduction of apoE4 domain interaction into mouse apoE in vivo. The Arg-61 apoE mouse model will allow the effects of apoE4 domain interaction in lipoprotein metabolism, atherosclerosis, and neurodegeneration to be determined.

  20. Apolipoprotein-E genotypes and myasthenia gravis.

    PubMed

    Suhail, Hamid; Soundararajan, Christhunesa C; Vivekanandhan, Subbiah; Singh, Sumit; Behari, Madhuri

    2010-01-01

    Autoimmune myasthenia gravis (MG) is a disorder of neuromuscular junction. Possible role of multiple genes in the development of the MG has been documented. This case-control study, studied the association of apolipoprotein E (Apo-E) alleles with MG. Anti-AChR antibody was measured using radio receptor immunoassay. Apo-E genotypes were analyzed in 120 MG patients and 120 healthy subjects. Comparison between patients with MG and controls showed no significant association with Apo-E allelic variants. However, a significant association of Apo-E4 allele with AChR-antibody positive patients was observed (P = 0.007). Also, among seropositive patients, a significant association was seen between female gender and Apo-E4 allele (P = 0.023). Our results suggest that the presence of Apo-E4 allele might influence seropositive status in patients with MG and seems an associated susceptible factor in female patients.

  1. Apolipoprotein E polymorphism and dendritic shape in hippocampal interneurons.

    PubMed

    Schönheit, Bärbel; Glöckner, Frauke; Ohm, Thomas G

    2007-05-01

    The apolipoprotein E genetic polymorphism exerts a well described influence on Alzheimer's disease (AD) risk, although the pathogenetic mechanism is still not clear. Increasing evidence points to a diminished neuroplasticity in apolipoprotein E varepsilon4-allele carriers. But, alternatively or additionally, developmental differences in dendritic geometry may be associated with the polymorphism. We morphometrically examined the dendritic ramification of CA1 Parvalbumin-positive GABAergic hippocampal neurons (n=571) in matched pairs of aged non-demented individuals with different apolipoprotein E genotype. We chose Parvalbumin-positive interneurons since they lack potentially confounding AD-like cytoskeletal changes. To minimize the risk of transneuronal dendritic changes due to significant deafferentation we focused on non-demented individuals. In this chosen paradigm, neither the disease-associated apolipoprotein E varepsilon4-allele nor the apolipoprotein E varepsilon2-allele had a significant impact on dendritic shape when compared to the most common allelic variant apolipoprotein E varepsilon3/3. At least with respect to the studied cell type, the data suggest that the apolipoprotein E polymorphism does not modulate the original formation of dendrites in vivo, contrary to conclusions drawn from in vitro studies on neurite outgrowth.

  2. Role of apolipoprotein E in neurodegenerative diseases

    PubMed Central

    Giau, Vo Van; Bagyinszky, Eva; An, Seong Soo A; Kim, Sang Yun

    2015-01-01

    Apolipoprotein E (APOE) is a lipid-transport protein abundantly expressed in most neurons in the central nervous system. APOE-dependent alterations of the endocytic pathway can affect different functions. APOE binds to cell-surface receptors to deliver lipids and to the hydrophobic amyloid-β peptide, regulating amyloid-β aggregations and clearances in the brain. Several APOE isoforms with major structural differences were discovered and shown to influence the brain lipid transport, glucose metabolism, neuronal signaling, neuroinflammation, and mitochondrial function. This review will summarize the updated research progress on APOE functions and its role in Alzheimer’s disease, Parkinson’s disease, cardiovascular diseases, multiple sclerosis, type 2 diabetes mellitus, Type III hyperlipoproteinemia, vascular dementia, and ischemic stroke. Understanding the mutations in APOE, their structural properties, and their isoforms is important to determine its role in various diseases and to advance the development of therapeutic strategies. Targeting APOE may be a potential approach for diagnosis, risk assessment, prevention, and treatment of various neurodegenerative and cardiovascular diseases in humans. PMID:26213471

  3. Apolipoprotein E receptor pathways in Alzheimer disease.

    PubMed

    Schmidt, Vanessa; Carlo, Anne-Sophie; Willnow, Thomas E

    2014-01-01

    Alzheimer disease (AD) is the most common neurodegenerative disease affecting millions of patients worldwide. According to the amyloid cascade hypothesis, the formation of neurotoxic oligomers composed of amyloid-β (Aβ) peptides is the main mechanism that causes synaptic dysfunction and, eventually, neuronal cell death in this condition. Intriguingly, apolipoprotein E (apoE), the most important genetic risk factor for sporadic AD, emerges as a key factor that contributes to many aspects of the amyloid cascade including the clearance of Aβ from brain interstitial fluid and the ability of this peptide to form neurotoxic oligomers. Central to the activity of apoE in the healthy and in the diseased brain are apoE receptors that interact with this protein to mediate its multiple cellular and systemic effects. This review describes the molecular interactions that link apoE and its cellular receptors with neuronal viability and function, and how defects in these pathways in the brain promote neurodegeneration. For further resources related to this article, please visit the WIREs website. The authors have declared no conflicts of interest for this article. © 2014 Wiley Periodicals, Inc.

  4. Apolipoprotein E pathology in vascular dementia.

    PubMed

    Rohn, Troy T; Day, Ryan J; Sheffield, Colin B; Rajic, Alexander J; Poon, Wayne W

    2014-01-01

    Vascular dementia (VaD) is the second most common form of dementia and is currently defined as a cerebral vessel vascular disease leading to ischemic episodes. Apolipoprotein E (apoE) gene polymorphism has been proposed as a risk factor for VaD, however, to date there are few documented post-mortem studies on apoE pathology in the VaD brain. To investigate a potential role for the apoE protein, we analyzed seven confirmed cases of VaD by immunohistochemistry utilizing an antibody that specifically detects the amino-terminal fragment of apoE. Application of this antibody, termed N-terminal, apoE cleavage fragment (nApoECF) revealed consistent labeling within neurofibrillary tangles (NFTs), blood vessels, and reactive astrocytes. Labeling occurred in VaD cases that had confirmed APOE genotypes of 3/3, 3/4, and 4/4, with respect to NFTs, staining of the nApoECF co-localized with PHF-1 and was predominantly localized to large, stellate neurons in layer II of the entorhinal cortex. Quantitative analysis indicated that approximately 38.4% of all identified NFTs contained the amino-terminal fragment of apoE. Collectively, these data support a role for the proteolytic cleavage of apoE in the VaD and support previous reports that APOE polymorphism is significantly associated with susceptibility in this disease.

  5. Apolipoprotein E: Risk factor for Alzheimer disease

    SciTech Connect

    Tsai, M.S.; Thibodeau, S.N.; Tangalos, E.G.; Petersen, R.C.; Kokmen, E.; Smith, G.E.; Schaid, D.J.; Ivnik, R.J. )

    1994-04-01

    The apolipoprotein E gene (APOE) has three common alleles (E2, E3, and E4) that determine six genotypes in the general population. In this study, the authors examined 77 patients with late-onset Alzheimer disease (AD), along with an equal number of age- and sex-matched controls, for an association with the APOE-E4 allele. They show that the frequency of this allele among AD patients was significantly higher than that among the control population (.351 vs. .130, P = .000006). The genotype frequencies also differed between the two groups (P = .0002), with the APOE-E4/E3 genotype being the most common in the AD group and the APOE-E3/E3 being the most common in the control group. In the AD group, homozygosity for E4 was found in nine individuals, whereas none was found in the control group. The odds ratio for AD, when associated with one or two E4 alleles, was 4.6 (95% confidence interval [CI] 1.9-12.3), while the odds ratio for AD, when associated with heterozygosity for APOE-E4, was 3.6 (05% CI 1.5-9.8). Finally, the median age at onset among the AD patients decreased from 83 to 78 to 74 years as the number of APOE-E4 alleles increased from 0 to 1 to 2, respectively (test for trend, P = .001). The data, which are in agreement with recent reports, suggest that the APOE-E4 allele is associated with AD and that this allelic variant may be an important risk factor for susceptibility to AD in the general population. 30 refs., 5 tabs.

  6. Porphyromonas gingivalis accelerates inflammatory atherosclerosis in the innominate artery of ApoE deficient mice.

    PubMed

    Hayashi, Chie; Viereck, Jason; Hua, Ning; Phinikaridou, Alkystis; Madrigal, Andrés G; Gibson, Frank C; Hamilton, James A; Genco, Caroline A

    2011-03-01

    Studies in humans support a role for the oral pathogen Porphyromonas gingivalis in the development of inflammatory atherosclerosis. The goal of this study was to determine if P. gingivalis infection accelerates inflammation and atherosclerosis in the innominate artery of mice, an artery which has been reported to exhibit many features of human atherosclerotic disease, including plaque rupture. Apolipoprotein E-deficient (ApoE-/-) mice were orally infected with P. gingivalis, and magnetic resonance imaging (MRI) was used to monitor the progression of atherosclerosis in live mice. P. gingivalis infected mice exhibited a statistically significant increase in atherosclerotic plaque in the innominate artery as compared to uninfected mice. Polarized light microscopy and immunohistochemistry revealed that the innominate arteries of infected mice had increased lipids, macrophages and T cells as compared to uninfected mice. Increases in plaque, total cholesterol esters and cholesterol monohydrate crystals, macrophages, and T cells were prevented by immunization with heat-killed P. gingivalis prior to pathogen exposure. These are the first studies to demonstrate progression of inflammatory plaque accumulation in the innominate arteries by in vivo MRI analysis following pathogen exposure, and to document protection from plaque progression in the innominate artery via immunization. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  7. Porphyromonas gingivalis Accelerates Inflammatory Atherosclerosis in the Innominate Artery of ApoE Deficient Mice

    PubMed Central

    Hayashi, Chie; Viereck, Jason; Hua, Ning; Phinikaridou, Alkystis; Madrigal, Andres G.; Gibson, Frank C.; Hamilton, James A.; Genco, Caroline A.

    2011-01-01

    Objective Studies in humans support a role for the oral pathogen Porphyromonas gingivalis in the development of inflammatory atherosclerosis. The goal of this study was to determine if P. gingivalis infection accelerates inflammation and atherosclerosis in the innominate artery of mice, an artery which has been reported to exhibit many features of human atherosclerotic disease, including plaque rupture. Methods and Results Apolipoprotein E-deficient (ApoE−/−) mice were orally infected with P. gingivalis, and Magnetic Resonance Imaging (MRI) was used to monitor the progression of atherosclerosis in live mice. P. gingivalis infected mice exhibited a statistically significant increase in atherosclerotic plaque in the innominate artery as compared to uninfected mice. Polarized light microscopy and immunohistochemistry revealed that the innominate arteries of infected mice had increased lipids, macrophages and T cells as compared to uninfected mice. Increases in plaque, total cholesterol esters and cholesterol monohydrate crystals, macrophages, and T cells were prevented by immunization with heat-killed P. gingivalis prior to pathogen exposure. Conclusions These are the first studies to demonstrate progression of inflammatory plaque accumulation in the innominate arteries by in-vivo MRI analysis following pathogen exposure, and to document protection from plaque progression in the innominate artery via immunization. PMID:21251656

  8. The effects of fish oil consumption on cardiovascular remodeling in ApoE deficient mice.

    PubMed

    Cleverley, Kelby; Du, Xiaozhou; Premecz, Sheena; Le, Khuong; Zeglinski, Matthew; Nicholson, Tiffany; Goh, Chun Y; Lu, Yan; Anderson, Hope D; Moghadasian, Mohammed H; Jassal, Davinder S

    2013-11-01

    Owing to their spontaneous development of atherosclerosis, apolipoprotein E knockout mice (ApoE(KO)) are one of the best studied animal models for this disease. Little is known about the utility of various omega-3 fatty acid regimens, in particular fish oils, in preventing cardiac disease in ApoE(KO) mice. The purpose of this study was to determine the cardiovascular effects of omega-3 fatty acid supplementation with either safflower oil (control), fish oil, flaxseed oil, or designed oil in ApoE(KO) mice fed a high-fat diet for a total of 16 weeks. In-vivo cardiac function was assessed weekly using murine echocardiography. Blood pressure, plasma lipid levels, and brain natriuretic peptide (BNP) were serially measured. The results show that ApoE(KO) mice fed fish oil demonstrated an increase in left ventricular wall thickness as a result of increased afterload. Despite chronic treatment with fish oil over 16 weeks, blood pressure increased in ApoE(KO) mice by 20% compared with the baseline. Both echocardiographic evidence of left ventricular hypertrophy and biochemical increase in BNP levels confirmed diastolic dysfunction in ApoE(KO) mice fed fish oil. This suggests that high-fat diet supplemented with fish oil may lead to adverse cardiovascular effects in ApoE deficient mice.

  9. Apolipoprotein E receptor 2 is involved in the thrombotic complications in a murine model of the antiphospholipid syndrome.

    PubMed

    Romay-Penabad, Zurina; Aguilar-Valenzuela, Renan; Urbanus, Rolf T; Derksen, Ronald H W M; Pennings, Maarten T T; Papalardo, Elizabeth; Shilagard, Tuya; Vargas, Gracie; Hwang, Yong; de Groot, Philip G; Pierangeli, Silvia S

    2011-01-27

    Antiphospholipid (aPL)/anti-β(2) glycoprotein I (anti-β(2)GPI) antibodies stimulates tissue factor (TF) expression within vasculature and in blood cells, thereby leading to increased thrombosis. Several cellular receptors have been proposed to mediate these effects, but no convincing evidence for the involvement of a specific one has been provided. We investigated the role of Apolipoprotein E receptor 2 (ApoER2') on the pathogenic effects of a patient-derived polyclonal aPL IgG preparation (IgG-APS), a murine anti-β(2)GPI monoclonal antibody (E7) and of a constructed dimeric β(2)GPI I (dimer), which in vitro mimics β(2)GPI-antibody immune complexes, using an animal model of thrombosis, and ApoER2-deficient (-/-) mice. In wild type mice, IgG-APS, E7 and the dimer increased thrombus formation, carotid artery TF activity as well as peritoneal macrophage TF activity/expression. Those pathogenic effects were significantly reduced in ApoER2 (-/-) mice. In addition, those effects induced by the IgG-APS, by E7 and by the dimer were inhibited by treatment of wild-type mice with soluble binding domain 1 of ApoER2 (sBD1). Altogether these data show that ApoER2 is involved in pathogenesis of antiphospholipids antibodies.

  10. Apolipoprotein E receptor 2 is involved in the thrombotic complications in a murine model of the antiphospholipid syndrome

    PubMed Central

    Romay-Penabad, Zurina; Aguilar-Valenzuela, Renan; Urbanus, Rolf T.; Derksen, Ronald H. W. M.; Pennings, Maarten T. T.; Papalardo, Elizabeth; Shilagard, Tuya; Vargas, Gracie; Hwang, Yong; de Groot, Philip G.

    2011-01-01

    Antiphospholipid (aPL)/anti-β2 glycoprotein I (anti-β2GPI) antibodies stimulates tissue factor (TF) expression within vasculature and in blood cells, thereby leading to increased thrombosis. Several cellular receptors have been proposed to mediate these effects, but no convincing evidence for the involvement of a specific one has been provided. We investigated the role of Apolipoprotein E receptor 2 (ApoER2′) on the pathogenic effects of a patient-derived polyclonal aPL IgG preparation (IgG-APS), a murine anti-β2GPI monoclonal antibody (E7) and of a constructed dimeric β2GPI I (dimer), which in vitro mimics β2GPI-antibody immune complexes, using an animal model of thrombosis, and ApoER2-deficient (−/−) mice. In wild type mice, IgG-APS, E7 and the dimer increased thrombus formation, carotid artery TF activity as well as peritoneal macrophage TF activity/expression. Those pathogenic effects were significantly reduced in ApoER2 (−/−) mice. In addition, those effects induced by the IgG-APS, by E7 and by the dimer were inhibited by treatment of wild-type mice with soluble binding domain 1 of ApoER2 (sBD1). Altogether these data show that ApoER2 is involved in pathogenesis of antiphospholipids antibodies. PMID:21119114

  11. Role of Apolipoprotein E in β-Amyloidogenesis

    PubMed Central

    Hori, Yukiko; Hashimoto, Tadafumi; Nomoto, Hidetoshi; Hyman, Bradley T.; Iwatsubo, Takeshi

    2015-01-01

    Human APOE ϵ4 allele is a strong genetic risk factor of Alzheimer disease. Neuropathological and genetic studies suggested that apolipoprotein E4 (apoE4) protein facilitates deposition of amyloid β peptide (Aβ) in the brain, although the mechanism whereby apoE4 increases amyloid aggregates remains elusive. Here we show that injection of Aβ protofibrils induced Aβ deposition in the brain of APP transgenic mice, suggesting that Aβ protofibrils acted as a seed for aggregation and deposition of Aβ in vivo. Injection of Aβ protofibrils together with apoE3 significantly attenuated Aβ deposition, whereas apoE4 did not have this effect. In vitro assays revealed that the conversion of Aβ protofibrils to fibrils progressed more slowly upon coincubation with apoE2 or apoE3 compared with that with apoE4. Aβ protofibrils complexed with apoE4 were less stable than those with apoE2 or apoE3. These data suggest that the suppression effect of apoE2 or apoE3 on the structural conversion of Aβ protofibrils to fibrils is stronger than those of apoE4, thereby impeding β-amyloid deposition. PMID:25918154

  12. Pharmacogenomic effects of Apolipoprotein E on Intracerebral Hemorrhage

    PubMed Central

    James, Michael L.; Sullivan, Patrick M.; Lascola, Christopher D.; Vitek, Michael P.; Laskowitz, Daniel T.

    2009-01-01

    Background and Purpose To evaluate the effect of APOE genotype and the feasibility of administering an apoE-mimetic therapeutic to modify outcomes in a murine model of intracerebral hemorrhage (ICH). Methods ICH was induced via stereotactic injection of 0.1 U Clostridial collagenase into the left basal ganglia of wild-type (WT) and apolipoprotein-E targeted-replacement (APOETR) mice, consisting of either homozygous 3/3 (APOE3TR) or 4/4 (APOE4TR) genotypes. Animals were randomized to receive either vehicle or apoE-mimetic peptide. Outcomes included functional neurological tests (21-point neuroseverity score and rotorod latency) over the initial 7 d after injury, radiographic and histological hemorrhage size at 3 and 7 d, brain water content for cerebral edema at 24 h, and q-PCR for inflammatory markers at 6, 24, and 48 h. Results APOE3TR animals demonstrated superior neuroseverity scores and rotorod latencies over the first 3 d after ICH, decreased cerebral edema at 24 h, and reduced up-regulation of IL-6 and eNOS at 6 h when compared to their APOE4TR counterparts. Following intravenous administration of 1 mg/kg apoE-mimetic peptide, both WT and APOE4TR animals exhibited improved functional outcomes over 7 d after ICH, less edema at 24 h and reduced up-regulation of IL-6 and eNOS when compared to mice that did not receive the peptide. Conclusions Our data indicate that APOE genotype influences neurological outcome after ICH in a murine model. In particular APOE4 is associated with poor functional outcome and increased cerebral edema. Additionally, this outcome can be modified by the addition of an apoE mimetic-peptide, COG1410. PMID:19109539

  13. Atypical chemokine receptor 1 deficiency reduces atherogenesis in ApoE-knockout mice.

    PubMed

    Wan, Wuzhou; Liu, Qian; Lionakis, Michail S; Marino, Ana Paula M P; Anderson, Stasia A; Swamydas, Muthulekha; Murphy, Philip M

    2015-06-01

    Atypical chemokine receptor 1 (Ackr1; previously known as the Duffy antigen receptor for chemokines or Darc) is thought to regulate acute inflammatory responses in part by scavenging inflammatory CC and CXC chemokines; however, evidence for a role in chronic inflammation has been lacking. Here we investigated the role of Ackr1 in chronic inflammation, in particular in the setting of atherogenesis, using the apolipoprotein E-deficient (ApoE(-/-)) mouse model. Ackr1(-/-)ApoE(-/-) and Ackr1(+/+)ApoE(-/-) littermates were obtained by crossing ApoE(-/-) mice and Ackr1(-/-) mice on a C57BL/6J background. Ackr1 (+/+)ApoE(-/-)mice fed a Western diet up-regulated Ackr1 expression in the aorta and had markedly increased atherosclerotic lesion size compared with Ackr1(-/-)ApoE(-/-) mice. This difference was observed in both the whole aorta and the aortic root in both early and late stages of the model. Ackr1 deficiency did not affect serum cholesterol levels or macrophage, collagen or smooth muscle cell content in atherosclerotic plaques, but significantly reduced the expression of Ccl2 and Cxcl1 in the whole aorta of ApoE(-/-) mice. In addition, Ackr1 deficiency resulted in a modest decrease in T cell subset frequency and inflammatory mononuclear phagocyte content in aorta and blood in the model. Ackr1 deficiency appears to be protective in the ApoE knockout model of atherogenesis, but it is associated with only modest changes in cytokine and chemokine expression as well as T-cell subset frequency and inflammatory macrophage content. Published by Oxford University Press on behalf of the European Society of Cardiology 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  14. Influence of copper deficiency on binding and uptake of apolipoprotein E-free high density lipoproteins (APO E-free HDL) by isolated rat liver parenchymal and Kupffer cells

    SciTech Connect

    Lei, K.Y.; Hendriks, H.F.J.; Brouwer, A.; Bock, I.; De Ruiter, C.S.J.; Knook, D.L. )

    1989-02-01

    Weanling male Sprague-Dawley rats were assigned to two dietary treatments; copper-deficient (CD, 0.7 ppm) and adequate (CA, 7.0 ppm). After 8 weeks, plasma apo E-free HDL were isolated by a combination of ultracentrifugation, gel filtration, and heparin-Sepharose affinity chromatography. Liver parenchymal (P) and Kupffer (K) cells were obtained by collagenase perfusion and purified by elutriation. Freshly isolated cells were then incubated with {sup 125}I-apo E-free HDL, either from the same treatment group or in a crossover design, in order to establish if treatment differences were associated with cells and/or lipoproteins. Binding studies performed at 4{degree}C with increasing apo E-free HDL concentration indicated an increase in specific binding in P cells from CD rats. In cell association studies at 37{degree}C, P cells from CD rats demonstrated increased in trypsin releasable (surface-bound) and total cell-associated apo E-free HDL. In contrast, K cells from CD rats demonstrated a reduction in apo E-free HDL uptake (internalized). These findings confirm data obtained from cultured P cells and indicated that copper deficiency may exert different effects on lipoprotein metabolism in rat liver parenchymal and Kupffer cells.

  15. Protein Inhibitor of Activated STAT3 Suppresses Oxidized LDL-induced Cell Responses during Atherosclerosis in Apolipoprotein E-deficient Mice

    PubMed Central

    Wang, Rong; Zhang, Yanjin; Xu, Liran; Lin, Yan; Yang, Xiaofeng; Bai, Liang; Chen, Yulong; Zhao, Sihai; Fan, Jianglin; Cheng, Xianwu; Liu, Enqi

    2016-01-01

    Atherosclerosis is a serious public health concern. Excessive inflammatory responses of vascular cells are considered a pivotal pathogenesis mechanism underlying atherosclerosis development. It is known that Janus kinase/signal transducer and activator of transcription 3 (JAK/STAT3) signalling plays an important role in atherosclerosis progression. Protein inhibitor of activated STAT3 (PIAS3) is the key negative regulator of JAK/STAT3 signalling. However, its effect on atherogenesis is unknown. Here, we observed that PIAS3 levels are reduced in atherosclerotic lesions and that PIAS3 expression decreases in conjunction with increases in interleukin-6 expression and atherosclerosis severity. Oxidized low-density lipoprotein (ox-LDL), an atherogenic stimulus, reduced PIAS3 expression, an effect that may be attributed to nitric oxide synthesis upregulation. In turn, PIAS3 overexpression effectively suppressed ox-LDL-induced inflammation, lipid accumulation and vascular smooth muscle cell proliferation. These results indicate that PIAS3 is a critical repressor of atherosclerosis progression. The findings of this study have contributed to our understanding on the pathogenesis of atherosclerosis and have provided us with a potential target through which we can inhibit atherosclerosis-related cellular responses. PMID:27845432

  16. Intermittent cold stress enhances features of atherosclerotic plaque instability in apolipoprotein E‑deficient mice.

    PubMed

    Zheng, Xi; Wang, Qiang; Zhang, Yan; Yang, Dachun; Li, De; Tang, Bing; Li, Xiuchuan; Yang, Yongjian; Ma, Shuangtao

    2014-10-01

    The cold weather is associated with an increased occurrence of acute coronary events. However, the mechanisms underlying cold‑induced myocardial infarctions have not yet been fully elucidated. In the present study, 20 male, eight week‑old, apolipoprotein E (ApoE)‑deficient mice were subjected to either control conditions or intermittent cold exposure for eight weeks. Mice in the cold group were placed in a cold room at 4˚C for 4 h per day, while the mice in the control group were kept in a room at 24˚C. Cold‑exposed mice did not significantly differ from control mice in body weight, fasting glucose concentration and plasma lipid levels, including triglyceride, total cholesterol, low‑density lipoprotein and high‑density lipoprotein. The hematoxylin and eosin‑stained sections of the aortic root demonstrated increased plaque size in the cold group compared with the control group (P<0.01). Furthermore, cold‑treated mice exhibited significantly decreased plaque collagen and vascular smooth muscle cell deposition and increased macrophage and lymphocyte content (P<0.05 or P<0.01), which are typical features of atherosclerotic plaque instability. Additionally, the protein expression of matrix metalloproteinase (MMP)‑2, MMP‑9 and MMP‑14 were significantly increased (P<0.05 or P<0.01), whereas tissue inhibitor of matrix metalloproteinase (TIMP)‑1 expression was decreased (P<0.05) following exposure to a cold environment. The present study demonstrated that chronic intermittent cold stress may increase atherosclerotic plaque size and promote plaque instability in ApoE‑deficient mice by altering the balance of MMPs and TIMPs. These findings may provide mechanistic insights into sudden cardiac death in cold environments.

  17. Wound healing in Mac-1 deficient mice.

    PubMed

    Chen, Lin; Nagaraja, Sridevi; Zhou, Jian; Zhao, Yan; Fine, David; Mitrophanov, Alexander Y; Reifman, Jaques; DiPietro, Luisa A

    2017-05-01

    Mac-1 (CD11b/CD18) is a macrophage receptor that plays several critical roles in macrophage recruitment and activation. Because macrophages are essential for proper wound healing, the impact of Mac-1 deficiency on wound healing is of significant interest. Prior studies have shown that Mac-1(-/-) mice exhibit deficits in healing, including delayed wound closure in scalp and ear wounds. This study examined whether Mac-1 deficiency influences wound healing in small excisional and incisional skin wounds. Three millimeter diameter full thickness excisional wounds and incisional wounds were prepared on the dorsal skin of Mac-1 deficient (Mac-1(-/-) ) and wild type (WT) mice, and wound healing outcomes were examined. Mac-1 deficient mice exhibited a normal rate of wound closure, generally normal levels of total collagen, and nearly normal synthesis and distribution of collagens I and III. In incisional wounds, wound breaking strength was similar for Mac-1(-/-) and WT mice. Wounds of Mac-1 deficient mice displayed normal total macrophage content, although macrophage phenotype markers were skewed as compared to WT. Interestingly, amounts of TGF-β1 and its downstream signaling molecules, SMAD2 and SMAD3, were significantly decreased in the wounds of Mac-1 deficient mice compared to WT. The results suggest that Mac-1 deficiency has little impact on the healing of small excisional and incisional wounds. Moreover, the findings demonstrate that the effect of single genetic deficiencies on wound healing may markedly differ among wound models. These conclusions have implications for the interpretation of the many prior studies that utilize a single model system to examine wound healing outcomes in genetically deficient mice. © 2017 by the Wound Healing Society.

  18. Magnesium deficiency impairs fear conditioning in mice.

    PubMed

    Bardgett, Mark E; Schultheis, Patrick J; McGill, Diana L; Richmond, Raymond E; Wagge, Jordan R

    2005-03-15

    Magnesium (Mg2+) is one of the most abundant cations found in the body. In the central nervous system, Mg2+ plays an important role in the function of N-methyl-D-aspartate (NMDA)-type glutamate receptors, which are centrally involved in memory processing. Despite the relatively large concentration of Mg2+ in the CNS, little is known about the behavioral consequences of Mg2+ deficiency. The purpose of this study was to address this issue by assessing fear conditioning and related behaviors in mice maintained on normal or Mg(2+)-deficient diets. Young adult male C57Bl/6J mice were placed on a control or Mg(2+)-deficient diet, and testing was conducted between 10 and 21 days later. Magnesium-deficient mice exhibited impairments in contextual and cued fear conditioning. These impairments could not be attributed to changes in locomotor activity, exploration, or pain sensitivity. Furthermore, Mg(2+)-deficient mice were more sensitive to the convulsant effects of a peripheral injection of NMDA (100 mg/kg, IP). The results suggest that magnesium deficiency can lead to specific impairments in emotional memory. Such impairments may be related to hypersensitivity of NMDA-type glutamate receptors in Mg(2+)-deficient mice.

  19. Hearing Dysfunction in Xpa-Deficient Mice

    PubMed Central

    Shinomiya, Hitomi; Yamashita, Daisuke; Fujita, Takeshi; Nakano, Eiji; Inokuchi, Go; Hasegawa, Shingo; Otsuki, Naoki; Nishigori, Chikako; Nibu, Ken-ichi

    2017-01-01

    Xeroderma pigmentosum (XP) is a rare recessive heredity disease caused by DNA repair impairment characterized by photosensitivity and neurologic symptoms in half of the cases. There are eight subtypes of XP: XP-A–XP-G and XP variant. Among eight subtypes, XP complementation group A (XP-A) display the lowest DNA repair ability and the severest cutaneous and neurologic symptoms. While its pathogenesis of skin symptoms have been well-studied, that of neurological symptoms, including sensorineural hearing loss (SNHL) remains unknown. Basic studies have suggested that SNHL may be caused by inner ear damage, including damage to the spiral ganglion neurons and organ of Corti, and that the XP-A is associated with most severe form of SNHL in humans. Here, we report the occurrence of SNHL in Xpa-deficient mice. Xpa-deficient mice and wild-type mice underwent measurements for auditory brainstem response, and the results revealed that Xpa-deficient mice exhibited significantly greater (p < 0.01) ABR thresholds at 4, 8, and 16 kHz than the wild-type mice. Furthermore, the number of spiral ganglion neurons was reduced in Xpa-deficient mice compared with that in wild-type mice, indicating that hearing loss may be related to spiral ganglion neuron deficiency, consistent with the few reports published in human patients with XP. These results provide important insights into the pathogenesis of SNHL in patients with XP-A. PMID:28239347

  20. Apolipoprotein E and Apolipoprotein E Receptors: Normal Biology and Roles in Alzheimer Disease

    PubMed Central

    Holtzman, David M.; Herz, Joachim; Bu, Guojun

    2012-01-01

    Apolipoprotein E (APOE) genotype is the major genetic risk factor for Alzheimer disease (AD); the ε4 allele increases risk and the ε2 allele is protective. In the central nervous system (CNS), apoE is produced by glial cells, is present in high-density-like lipoproteins, interacts with several receptors that are members of the low-density lipoprotein receptor (LDLR) family, and is a protein that binds to the amyloid-β (Aβ) peptide. There are a variety of mechanisms by which apoE isoform may influence risk for AD. There is substantial evidence that differential effects of apoE isoform on AD risk are influenced by the ability of apoE to affect Aβ aggregation and clearance in the brain. Other mechanisms are also likely to play a role in the ability of apoE to influence CNS function as well as AD, including effects on synaptic plasticity, cell signaling, lipid transport and metabolism, and neuroinflammation. ApoE receptors, including LDLRs, Apoer2, very low-density lipoprotein receptors (VLDLRs), and lipoprotein receptor-related protein 1 (LRP1) appear to influence both the CNS effects of apoE as well as Aβ metabolism and toxicity. Therapeutic strategies based on apoE and apoE receptors may include influencing apoE/Aβ interactions, apoE structure, apoE lipidation, LDLR receptor family member function, and signaling. Understanding the normal and disease-related biology connecting apoE, apoE receptors, and AD is likely to provide novel insights into AD pathogenesis and treatment. PMID:22393530

  1. Apple juice prevents oxidative stress and impaired cognitive performance caused by genetic and dietary deficiencies in mice.

    PubMed

    Rogers, E J; Milhalik, S; Orthiz, D; Shea, T B

    2004-01-01

    Increased oxidative stress contributes to the decline in cognitive performance during normal aging and in neurodegenerative conditions such as Alzheimer s disease. Dietary supplementation with fruits and vegetables that are high in antioxidant potential have in some cases compensated for dietary and/or genetic deficiencies that promote increased oxidative stress. Herein, we demonstrate that apple juice concentrate, administered ad libitum in drinking water, can compensate for the increased reactive oxygen species and decline in cognitive performance in maze trials observed when normal and transgenic mice lacking apolipoprotein E are deprived of folate and vitamin E. In addition, we demonstrate that this protective effect is not derived from the sugar content of the concentrate.

  2. Profound induction of hepatic cholesteryl ester transfer protein transgene expression in apolipoprotein E and low density lipoprotein receptor gene knockout mice. A novel mechanism signals changes in plasma cholesterol levels.

    PubMed Central

    Masucci-Magoulas, L; Plump, A; Jiang, X C; Walsh, A; Breslow, J L; Tall, A R

    1996-01-01

    The plasma cholesteryl ester transfer protein (CETP) mediates the transfer of cholesteryl esters from HDL to other lipoproteins and is a key regulated component of reverse cholesterol transport. Dietary hypercholesterolemia results in increased hepatic CETP gene transcription and higher plasma CETP levels. To investigate the mechanisms by which the liver senses hypercholesterolemia, mice containing a natural flanking region CETP transgene (NFR-CETP transgene) were bred with apo E or LDL receptor gene knockout mice (E0 or LDLr0 mice). Compared to NFR-CETP transgenic (Tg) mice with intact apo E genes, in NFR-CETP Tg/E0 mice there was an eightfold induction of plasma CETP levels and a parallel increase in hepatic CETP mRNA levels. Other sterol-responsive genes (LDL receptor and hydroxymethyl glutaryl CoA reductase) also showed evidence of altered regulation with decreased abundance of their mRNAs in the E0 background. A similar induction of plasma CETP and hepatic CETP mRNA levels resulted from breeding the NFR-CETP transgene into the LDL receptor gene knockout background. When placed on a high cholesterol diet, there was a further increase in CETP levels in both E0 and LDLr0 backgrounds. In CETP Tg, CETP Tg/E0, and CETP Tg/LDLr0 mice on different diets, plasma CETP and CETP mRNA levels were highly correlated with plasma cholesterol levels. The results indicate that hepatic CETP gene expression is driven by a mechanism which senses changes in plasma cholesterol levels independent of apo E and LDL receptors. Hepatic sterol-sensitive genes have mechanisms to sense hypercholesterolemia that do not require classical receptor-mediated lipoprotein uptake. PMID:8550828

  3. Haploinsufficiency of E-selectin ligand-1 is associated with reduced atherosclerotic plaque macrophage content while complete deficiency leads to early embryonic lethality in mice.

    PubMed

    Luo, Wei; Wang, Hui; Guo, Chiao; Wang, Jintao; Kwak, Jeffrey; Bahrou, Kristina L; Eitzman, Daniel T

    2012-10-01

    E-selectin-1 (ESL-1), also known as golgi complex-localized glycoprotein-1 (GLG1), homocysteine-rich fibroblast growth factor receptor (CGR-1), and latent transforming growth factor-β complex protein 1 (LTCP-1), is a multifunctional protein with widespread tissue distribution. To determine the functional consequences of ESL-1 deficiency, mice were generated carrying an ESL-1 gene trap. After backcrossing to C57BL6/J for 6 generations, mice heterozygous for the gene trap (ESL-1(+/-)) were intercrossed to produce ESL-1(-/-) mice, however ESL-1(-/-) mice were not viable, even at embryonic day E10.5. To determine the effect of heterozygous ESL-1 deficiency on atherosclerosis, apolipoprotein E deficient (ApoE(-/-)), ESL-1(+/-) mice were generated and fed western diet. Compared to ApoE(-/-), ESL-1(+)(/)(+) mice, atherosclerotic lesions from ApoE(-/-), ESL-1(+/-) contained more collagen and fewer macrophages, suggesting increased plaque stability. In conclusion, heterozygous deficiency of ESL-1 is associated with features of increased atherosclerotic plaque stability while complete deficiency of ESL-1 leads to embryonic lethality.

  4. Hyperhomocysteinemia promotes inflammatory monocyte generation and accelerates atherosclerosis in transgenic cystathionine beta-synthase-deficient mice.

    PubMed

    Zhang, Daqing; Jiang, Xiaohua; Fang, Pu; Yan, Yan; Song, Jian; Gupta, Sapna; Schafer, Andrew I; Durante, William; Kruger, Warren D; Yang, Xiaofeng; Wang, Hong

    2009-11-10

    Hyperhomocysteinemia (HHcy) is an independent risk factor for cardiovascular disease. Monocytes display inflammatory and resident subsets and commit to specific functions in atherogenesis. In this study, we examined the hypothesis that HHcy modulates monocyte heterogeneity and leads to atherosclerosis. We established a novel atherosclerosis-susceptible mouse model with both severe HHcy and hypercholesterolemia in which the mouse cystathionine beta-synthase (CBS) and apolipoprotein E (apoE) genes are deficient and an inducible human CBS transgene is introduced to circumvent the neonatal lethality of the CBS deficiency (Tg-hCBS apoE(-/-) Cbs(-/-) mice). Severe HHcy accelerated atherosclerosis and inflammatory monocyte/macrophage accumulation in lesions and increased plasma tumor necrosis factor-alpha and monocyte chemoattractant protein-1 levels in Tg-hCBS apoE(-/-) Cbs(-/-) mice fed a high-fat diet. Furthermore, we characterized monocyte heterogeneity in Tg-hCBS apoE(-/-) Cbs(-/-) mice and another severe HHcy mouse model (Tg-S466L Cbs(-/-)) with a disease-relevant mutation (Tg-S466L) that lacks hyperlipidemia. HHcy increased monocyte population and selective expansion of inflammatory Ly-6C(hi) and Ly-6C(mid) monocyte subsets in blood, spleen, and bone marrow of Tg-S466L Cbs(-/-) and Tg-hCBS apoE(-/-) Cbs(-/-) mice. These changes were exacerbated in Tg-S466L Cbs(-/-) mice with aging. Addition of l-homocysteine (100 to 500 micromol/L), but not l-cysteine, maintained the Ly-6C(hi) subset and induced the Ly-6C(mid) subset in cultured mouse primary splenocytes. Homocysteine-induced differentiation of the Ly-6C(mid) subset was prevented by catalase plus superoxide dismutase and the NAD(P)H oxidase inhibitor apocynin. HHcy promotes differentiation of inflammatory monocyte subsets and their accumulation in atherosclerotic lesions via NAD(P)H oxidase-mediated oxidant stress.

  5. Accumulation of Oxidized LDL in the Tendon Tissues of C57BL/6 or Apolipoprotein E Knock-Out Mice That Consume a High Fat Diet: Potential Impact on Tendon Health

    PubMed Central

    Grewal, Navdeep; Thornton, Gail M.; Behzad, Hayedeh; Sharma, Aishwariya; Lu, Alex; Zhang, Peng; Reid, W. Darlene; Granville, David J.; Scott, Alex

    2014-01-01

    Objective Clinical studies have suggested an association between dyslipidemia and tendon injuries or chronic tendon pain; the mechanisms underlying this association are not yet known. The objectives of this study were (1) to evaluate the impact of a high fat diet on the function of load-bearing tendons and on the distribution in tendons of oxidized low density lipoprotein (oxLDL), and (2) to examine the effect of oxLDL on tendon fibroblast proliferation and gene expression. Methods Gene expression (Mmp2, Tgfb1, Col1a1, Col3a1), fat content (Oil Red O staining), oxLDL levels (immunohistochemistry) and tendon biomechanical properties were examined in mice (C57Bl/6 or ApoE -/-) receiving a standard or a high fat diet. Human tendon fibroblast proliferation and gene expression (COL1A1, COL3A1, MMP2) were examined following oxLDL exposure. Results In both types of mice (C57Bl/6 or ApoE -/-), consumption of a high fat diet led to a marked increase in oxLDL deposition in the load-bearing extracellular matrix of the tendon. The consumption of a high fat diet also reduced the failure stress and load of the patellar tendon in both mouse types, and increased Mmp2 expression. ApoE -/- mice exhibited more pronounced reductions in tendon function than wild-type mice, and decreased expression of Col1a1 compared to wild type mice. Human tendon fibroblasts responded to oxLDL by increasing their proliferation and their mRNA levels of MMP2, while decreasing their mRNA levels for COL1A1 and COL3A1. Conclusion The consumption of a high fat diet resulted in deleterious changes in tendon function, and these changes may be explained in part by the effects of oxLDL, which induced a proliferative, matrix-degrading phenotype in human tenocytes. PMID:25502628

  6. Apolipoprotein E: from lipid transport to neurobiology

    PubMed Central

    Hauser, Paul S.; Narayanaswami, Vasanthy; Ryan, Robert O.

    2010-01-01

    Apolipoprotein (apo) E has a storied history as a lipid transport protein. The integral association between cholesterol homeostasis and lipoprotein clearance from circulation are intimately related to apoE's function as a ligand for cell surface receptors of the low density lipoprotein receptor family. The receptor binding properties of apoE are strongly influenced by isoform specific amino acid differences as well as the lipidation state of the protein. As understanding of apoE as a structural component of circulating plasma lipoproteins has evolved, exciting developments in neurobiology have revitalized interest in apoE. The strong and enduring correlation between the apoE4 isoform and age of onset and increased risk of Alzheimer's disease has catapulted apoE to the forefront of neurobiology. Using genetic tools generated for study of apoE lipoprotein metabolism, transgenic “knock-in” and gene-disrupted mice are now favored models for study of its role in a variety of neurodegenerative diseases. Key structural knowledge of apoE and isoform specific differences is driving research activity designed to elucidate how a single amino acid change can manifest such profoundly significant pathological consequences. This review describes apoE through a lens of structure-based knowledge that leads to hypotheses that attempt to explain the functions of apoE and isoform specific effects relating to disease mechanism. PMID:20854843

  7. Specific Regional Transcription of Apolipoprotein E in Human Brain Neurons

    PubMed Central

    Xu, Pu-Ting; Gilbert, John R.; Qiu, Hui-Ling; Ervin, John; Rothrock-Christian, Tracie R.; Hulette, Christine; Schmechel, Donald E.

    1999-01-01

    In central nervous system injury and disease, apolipoprotein E (APOE, gene; apoE, protein) might be involved in neuronal injury and death indirectly through extracellular effects and/or more directly through intracellular effects on neuronal metabolism. Although intracellular effects could clearly be mediated by neuronal uptake of extracellular apoE, recent experiments in injury models in normal rodents and in mice transgenic for the human APOE gene suggest the additional possibility of intraneuronal synthesis. To examine whether APOE might be synthesized by human neurons, we performed in situ hybridization on paraffin-embedded and frozen brain sections from three nondemented controls and five Alzheimer’s disease (AD) patients using digoxigenin-labeled antisense and sense cRNA probes to human APOE. Using the antisense APOE probes, we found the expected strong hybridization signal in glial cells as well as a generally fainter signal in selected neurons in cerebral cortex and hippocampus. In hippocampus, many APOE mRNA-containing neurons were observed in sectors CA1 to CA4 and the granule cell layer of the dentate gyrus. In these regions, APOE mRNA containing neurons could be observed adjacent to nonhybridizing neurons of the same cell class. APOE mRNA transcription in neurons is regionally specific. In cerebellar cortex, APOE mRNA was seen only in Bergmann glial cells and scattered astrocytes but not in Purkinje cells or granule cell neurons. ApoE immunocytochemical localization in semi-adjacent sections supported the selectivity of APOE transcription. These results demonstrate the expected result that APOE mRNA is transcribed and expressed in glial cells in human brain. The important new finding is that APOE mRNA is also transcribed and expressed in many neurons in frontal cortex and human hippocampus but not in neurons of cerebellar cortex from the same brains. This regionally specific human APOE gene expression suggests that synthesis of apoE might play a role

  8. Melissa officinalis essential oil reduces plasma triglycerides in human apolipoprotein E2 transgenic mice by inhibiting sterol regulatory element-binding protein-1c-dependent fatty acid synthesis.

    PubMed

    Jun, Hee-Jin; Lee, Ji Hae; Jia, Yaoyao; Hoang, Minh-Hien; Byun, Hanna; Kim, Kyoung Heon; Lee, Sung-Joon

    2012-03-01

    We investigated the hypolipidemic effects of Melissa officinalis essential oil (MOEO) in human APOE2 transgenic mice and lipid-loaded HepG2 cells. Plasma TG concentrations were significantly less in APOE2 mice orally administered MOEO (12.5 μg/d) for 2 wk than in the vehicle-treated group. Cellular TG and cholesterol concentrations were also significantly decreased in a dose- (400 and 800 mg/L) and time- (12 and 24 h) dependent manner in HepG2 cells stimulated with MOEO compared with controls. Mouse hepatic transcriptome analysis suggested MOEO feeding altered several lipid metabolic pathways, including bile acid and cholesterol synthesis and fatty acid metabolism. In HepG2 cells, the rate of fatty acid oxidation, as assessed using [1-(14)C]palmitate, was unaltered; however, the rate of fatty acid synthesis quantified with [1-(14)C]acetate was significantly reduced by treatment with 400 and 800 mg/L MOEO compared with untreated controls. This reduction was due to the decreased expression of SREBP-1c and its responsive genes in fatty acid synthesis, including FAS, SCD1, and ACC1. Subsequent chromatin immunoprecipitation analysis further demonstrated that the binding of p300/CBP-associated factor, a coactivator of SREBP-1c, and histone H3 lysine 14 acetylation at the FAS, SCD1, and ACC1 promoters were significantly reduced in the livers of APOE2 mice and HepG2 cells treated with MOEO compared with their controls. Additionally, MOEO stimulation in HepG2 cells induced bile acid synthesis and reduced the nuclear form of SREBP-2, a key transcription factor in hepatic cholesterol synthesis. These findings suggest that the intake of phytochemicals with pleasant scent could have beneficial metabolic effects.

  9. Adult neurogenesis in serotonin transporter deficient mice.

    PubMed

    Schmitt, A; Benninghoff, J; Moessner, R; Rizzi, M; Paizanis, E; Doenitz, C; Gross, S; Hermann, M; Gritti, A; Lanfumey, L; Fritzen, S; Reif, A; Hamon, M; Murphy, D L; Vescovi, A; Lesch, K-P

    2007-09-01

    Serotonin (5-HT) is a regulator of morphogenetic activities during early brain development and neurogenesis, including cell proliferation, migration, differentiation, and synaptogenesis. The 5-HT transporter (5-HTT, SLC6A4) mediates high-affinity reuptake of 5-HT into presynaptic terminals and thereby fine-tunes serotonergic neurotransmission. Inactivation of the 5-HTT gene in mice reduces 5-HT clearance resulting in persistently increased concentrations of synaptic 5-HT. In the present study, we investigated the effects of elevated 5-HT levels on adult neurogenesis in the hippocampus of 5-HTT deficient mice, including stem cell proliferation, survival, and differentiation. Using an in vivo approach, we showed an increase in proliferative capacity of hippocampal adult neural stem cells in aged 5-HTT knockout mice (approximately 14.5 months) compared to wildtype controls. In contrast, in vivo and additional in vitro analyses of younger adult 5-HTT knockout mice (approximately 7 weeks and approximately 3.0 months) did not reveal significant changes in proliferation of neural stem cells or survival of newborn cells. We showed that the cellular fate of newly generated cells in 5-HTT knockout mice is not different with respect to the total number and percentage of neurons or glial cells from wildtype controls. Our findings indicate that elevated synaptic 5-HT concentration throughout early development and later life of 5-HTT deficient mice does not induce adult neurogenesis in adult mice, but that elevated 5-HT levels in aged mice influence stem cell proliferation.

  10. Palmoplantar Keratoderma in Slurp2-Deficient Mice.

    PubMed

    Allan, Christopher M; Procaccia, Shiri; Tran, Deanna; Tu, Yiping; Barnes, Richard H; Larsson, Mikael; Allan, Bernard B; Young, Lorraine C; Hong, Cynthia; Tontonoz, Peter; Fong, Loren G; Young, Stephen G; Beigneux, Anne P

    2016-02-01

    SLURP1, a member of the lymphocyte antigen 6 protein family, is secreted by suprabasal keratinocytes. Mutations in SLURP1 cause a palmoplantar keratoderma (PPK) known as mal de Meleda. SLURP2, another secreted lymphocyte antigen 6 protein, is encoded by a gene located ?20 kb downstream from SLURP1. SLURP2 is produced by suprabasal keratinocytes. To investigate the importance of SLURP2, we first examined Slurp2 knockout mice in which exon 2-3 sequences had been replaced with lacZ and neo cassettes. Slurp2(-/-) mice exhibited hyperkeratosis on the volar surface of the paws (i.e., palmoplantar keratoderma), increased keratinocyte proliferation, and an accumulation of lipid droplets in the stratum corneum. They also exhibited reduced body weight and hind limb clasping. These phenotypes are similar to those of Slurp1(-/-) mice. To solidify a link between Slurp2 deficiency and palmoplantar keratoderma and to be confident that the disease phenotypes in Slurp2(-/-) mice were not secondary to the effects of the lacZ and neo cassettes on Slurp1 expression, we created a new line of Slurp2 knockout mice (Slurp2X(-/-)) in which Slurp2 was inactivated with a simple nonsense mutation. Slurp2X(-/-) mice exhibited the same disease phenotypes. Thus, Slurp2 deficiency and Slurp1 deficiencies cause the same disease phenotypes.

  11. Diethanolamine induces hepatic choline deficiency in mice.

    PubMed

    Lehman-McKeeman, Lois D; Gamsky, Elizabeth A; Hicks, Sarah M; Vassallo, Jeffrey D; Mar, Mei-Heng; Zeisel, Steven H

    2002-05-01

    The purpose of the present experiments was to test the hypothesis that diethanolamine (DEA), an alkanolamine shown to be hepatocarcinogenic in mice, induces hepatic choline deficiency and to determine whether altered choline homeostasis was causally related to the carcinogenic outcome. To examine this hypothesis, the biochemical and histopathological changes in male B6C3F1 mice made choline deficient by dietary deprivation were first determined. Phosphocholine (PCho), the intracellular storage form of choline was severely depleted, decreasing to about 20% of control values with 2 weeks of dietary choline deficiency. Other metabolites, including choline, glycerophosphocholine (GPC), and phosphatidylcholine (PC) also decreased. Hepatic concentrations of S-adenosylmethionine (SAM) decreased, whereas levels of S-adenosylhomocysteine (SAH) increased. Despite these biochemical changes, fatty liver, which is often associated with choline deficiency, was not observed in the mice. The dose response, reversibility, and strain-dependence of the effects of DEA on choline metabolites were studied. B6C3F1 mice were dosed dermally with DEA (0, 10, 20, 40, 80, and 160 mg/kg) for 4 weeks (5 days/week). Control animals received either no treatment or dermal application of 95% ethanol (1.8 ml/kg). PCho was most sensitive to DEA treatment, decreasing at dosages of 20 mg/kg and higher and reaching a maximum 50% depletion at 160 mg/kg/day. GPC, choline, and PC also decreased in a dose-dependent manner. At 80 and 160 mg/kg/day, SAM levels decreased while SAH levels increased in liver. A no-observed effect level (NOEL) for DEA-induced changes in choline homeostasis was 10 mg/kg/day. Choline metabolites, SAM and SAH returned to control levels in mice dosed at 160 mg/kg for 4 weeks and allowed a 2-week recovery period prior to necropsy. In a manner similar to dietary choline deficiency, no fatty change was observed in the liver of DEA-treated mice. In C57BL/6 mice, DEA treatment (160 mg

  12. A deficiency of Herp, an endoplasmic reticulum stress protein, suppresses atherosclerosis in ApoE knockout mice by attenuating inflammatory responses.

    PubMed

    Shinozaki, Shohei; Chiba, Tsuyoshi; Kokame, Koichi; Miyata, Toshiyuki; Kaneko, Eiji; Shimokado, Kentaro

    2013-01-01

    Herp was originally identified as an endoplasmic reticulum (ER) stress protein in vascular endothelial cells. ER stress is induced in atherosclerotic lesions, but it is not known whether Herp plays any role in the development of atherosclerosis. To address this question, we generated Herp- and apolipoprotein E (apoE)-deficient mice (Herp(-/-); apoE(-/-) mice) by crossbreeding Herp(-/-) mice and apoE(-/-) mice. Herp was expressed in the endothelial cells and medial smooth muscle cells of the aorta, as well as in a subset of macrophages in the atherosclerotic lesions in apoE(-/-) mice, while there was no expression of Herp in the Herp(-/-); apoE(-/-) mice. The doubly deficient mice developed significantly fewer atherosclerotic lesions than the apoE(-/-) mice at 36 and 72 weeks of age, whereas the plasma levels of cholesterol and triglycerides were not significantly different between the strains. The plasma levels of non-esterified fatty acids were significantly lower in the Herp(-/-); apoE(-/-) mice when they were eight and 16 weeks old. The gene expression levels of ER stress response proteins (GRP78 and CHOP) and inflammatory cytokines (IL-1β, IL-6, TNF-α and MCP-1) in the aorta were significantly lower in Herp(-/-); apoE(-/-) mice than in apoE(-/-) mice, suggesting that Herp mediated ER stress-induced inflammation. In fact, peritoneal macrophages isolated from Herp-deficient mice and RAW264.7 macrophages in which Herp was eliminated with a siRNA expressed lower levels of mRNA for inflammatory cytokines when they were treated with tunicamycin. Herp deficiency affected the major mediators of the unfolded protein response, including IRE1 and PERK, but not ATF6. These findings suggest that a deficiency of Herp suppressed the development of atherosclerosis by attenuating the ER stress-induced inflammatory reactions.

  13. α-Lipoic Acid Protects Diabetic Apolipoprotien E-deficient Mice from Nephropathy

    PubMed Central

    Yi, Xianwen; Nickeleit, Volker; James, Leighton R; Maeda, Nobuyo

    2010-01-01

    Aim Both hyperglycemia and hyperlipidemia increase oxidative stress, and contribute to the development of diabetic nephropathy (DN). We investigated effects of α-lipoic acid, a natural antioxidant and a cofactor in the multienzyme complexes, on the development of DN in diabetic apolipoprotein E-deficient mice. Methods Twelve-weeks-old male apoE−/− mice on C57BL/6J genetic background were made diabetic with injections of streptozotocin (STZ). STZ-treated diabetic apoE−/− mice and non-diabetic control were fed with a synthetic high fat (HF) diet with or without LA supplementation. Multiple parameters including plasma glucose, cholesterol, oxidative stress markers, cytokines, and kidney cortex gene expression, and glomerular morphology were evaluated. Results LA supplementation markedly protected the beta cells and reduced cholesterol levels, attenuated albuminuria and glomerular mesangial expansion in the diabetic mice. Reno-protection by LA was equally effective regardless of whether the dietary supplementation was started 4 weeks before, simultaneously with, or 4 weeks after the induction of diabetes by STZ. LA supplementation significantly improved DN and oxidative stress in the diabetic mice. Severity of albuminuria was positively correlated with level of thiobarbituric acid reactive substances (TBARs) in the kidney (r2=0.62, P<0.05). Diabetes significantly changed the kidney expression of Rage, Sod2, Tgfb1 and Ctgf, Pdp2, nephrin and Lias. LA supplementation corrected these changes except that it further suppressed the expression of the Lias gene coding for lipoic acid synthase. Conclusions Our data indicate that LA supplementation effectively attenuates the development and progression of DN through its antioxidant effect as well as enhancing glucose oxidation. PMID:20801062

  14. Noninvasive in vivo magnetic resonance imaging of injury-induced neointima formation in the carotid artery of the apolipoprotein-E null mouse.

    PubMed

    Manka, D R; Gilson, W; Sarembock, I; Ley, K; Berr, S S

    2000-11-01

    Mice deficient in apolipoprotein-E (apoE) experience severe hypercholesterolemia, are prone to atherosclerosis, and recently have emerged as a powerful tool in the study of plaque formation. In this study, we developed magnetic resonance (MR) imaging methods to detect the progression of atherosclerosis noninvasively in a mouse model of arterial injury. Four 14-week-old apoE-deficient mice were imaged 5 weeks after beginning an atherogenic Western diet and 4 weeks after wire denudation injury of the left common carotid artery (LCCA). Information from several images was combined into high-information content images using methods previously developed. The image resolution was 47 x 47 x 750 microm(3). We acquired T1-, T2-, and proton density (PD)-weighted images (TR/TE 650/14, 2000/60, and 2000/14 msec, respectively). Each 8-bit image was placed in a separate color channel to produce a 24-bit color image (red = T1, green = PD, and blue = T2). The composite image created contrast between different tissue types that was superior to that of any single image and revealed significant luminal narrowing of the LCCA, but not the uninjured RCCA. MR images were compared with corresponding histopathology cross sections and luminal area measurements from each method correlated(r2= 0.61). Atherosclerotic luminal narrowing was successfully detected through MR imaging in a mouse model of arterial injury that is small, reproduces quickly, and lends itself to genetic analysis and manipulation.

  15. Apolipoproteins E and AV mediate lipoprotein clearance by hepatic proteoglycans

    PubMed Central

    Gonzales, Jon C.; Gordts, Philip L.S.M.; Foley, Erin M.; Esko, Jeffrey D.

    2013-01-01

    The heparan sulfate proteoglycan (HSPG) syndecan-1 (SDC1) acts as a major receptor for triglyceride-rich lipoprotein (TRL) clearance in the liver. We sought to identify the relevant apolipoproteins on TRLs that mediate binding to SDC1 and determine their clinical relevance. Evidence supporting ApoE as a major determinant arose from its enrichment in TRLs from mice defective in hepatic heparan sulfate (Ndst1f/fAlbCre+ mice), decreased binding of ApoE-deficient TRLs to HSPGs on human hepatoma cells, and decreased clearance of ApoE-deficient [3H]TRLs in vivo. Evidence for a second ligand was suggested by the faster clearance of ApoE-deficient TRLs after injection into WT Ndst1f/fAlbCre– versus mutant Ndst1f/fAlbCre+ mice and elevated fasting and postprandial plasma triglycerides in compound Apoe–/–Ndst1f/fAlbCre+ mice compared with either single mutant. ApoAV emerged as a candidate based on 6-fold enrichment of ApoAV in TRLs accumulating in Ndst1f/fAlbCre+ mice, decreased binding of TRLs to proteoglycans after depletion of ApoAV or addition of anti-ApoAV mAb, and decreased heparan sulfate–dependent binding of ApoAV-deficient particles to hepatocytes. Importantly, disruption of hepatic heparan sulfate–mediated clearance increased atherosclerosis. We conclude that clearance of TRLs by hepatic HSPGs is atheroprotective and mediated by multivalent binding to ApoE and ApoAV. PMID:23676495

  16. Folic acid supplementation delays atherosclerotic lesion development in apoE-deficient mice.

    PubMed

    Carnicer, Ricardo; Navarro, María A; Arbonés-Mainar, José M; Acín, Sergio; Guzmán, Mario A; Surra, Joaquín C; Arnal, Carmen; de Las Heras, Marcelo; Blanco-Vaca, Francisco; Osada, Jesús

    2007-01-23

    Folic acid is a vitamin that when used as a dietary supplementation can improve endothelial function. To assess the effect of folic acid on the development of atherosclerosis, male apolipoprotein E-deficient mice fed a standard chow diet received either water (control group) or an aqueous solution of folic acid that provided a dose of 75 microg/kg/day, for ten weeks. At the time of sacrifice, blood was drawn and the heart removed. The study measured plasma homocysteine, lipids, lipoproteins, low-density lipoprotein (LDL) oxidation, isoprostane, paraoxonase, and apolipoproteins, and aortic atherosclerotic areas. In folic acid-treated animals, total cholesterol, mainly carried in very low-density and low-density lipoproteins, increased significantly, and homocysteine, HDL cholesterol, paraoxonase, and triglyceride levels did not change significantly. Plasma isoprostane and apolipoprotein (apo) B levels decreased. The resistance of LDL to oxidization and plasma apoA-I and apoA-IV levels increased with a concomitant decrease in the area of atherosclerotic lesions. The administration of folic acid decreased atherosclerotic lesions independently of plasma homocysteine and cholesterol levels, but was associated with plasma levels of apolipoproteins A-I, A-IV and B, and decreased oxidative stress.

  17. Wallerian degeneration in ICAM-1-deficient mice.

    PubMed Central

    Vougioukas, V. I.; Roeske, S.; Michel, U.; Brück, W.

    1998-01-01

    Wallerian degeneration of the peripheral nervous system was studied in ICAM-1-deficient mice and compared with the phenomena observed in C57BL wild-type animals. There was a decrease in myelin density in both mice strains 4 and 6 days after transection of the sciatic nerve. The degenerating nerves were invaded by Mac-1-, LFA-1-, and F4/80-positive macrophages; significantly lower numbers of macrophages were present in ICAM-1-deficient nerves. Myelin loss decreased after nerve transection with a more prominent loss in ICAM-1-deficient animals. Schwann cells revealed a much higher myelin load in these animals when compared with wild-type nerves, and there was an increased proliferation of endoneurial cells in ICAM-1-deficient mice. These data indicate that ICAM-1 is involved in macrophage recruitment to injured peripheral nerves as well as in the proliferative and phagocytic response of Schwann cells after peripheral nerve transection. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:9422541

  18. Circadian behaviour in neuroglobin deficient mice.

    PubMed

    Hundahl, Christian A; Fahrenkrug, Jan; Hay-Schmidt, Anders; Georg, Birgitte; Faltoft, Birgitte; Hannibal, Jens

    2012-01-01

    Neuroglobin (Ngb), a neuron-specific oxygen-binding globin with an unknown function, has been proposed to play a key role in neuronal survival. We have previously shown Ngb to be highly expressed in the rat suprachiasmatic nucleus (SCN). The present study addresses the effect of Ngb deficiency on circadian behavior. Ngb-deficient and wild-type (wt) mice were placed in running wheels and their activity rhythms, endogenous period and response to light stimuli were investigated. The effect of Ngb deficiency on the expression of Period1 (Per1) and the immediate early gene Fos was determined after light stimulation at night and the neurochemical phenotype of Ngb expressing neurons in wt mice was characterized. Loss of Ngb function had no effect on overall circadian entrainment, but resulted in a significantly larger phase delay of circadian rhythm upon light stimulation at early night. A light-induced increase in Per1, but not Fos, gene expression was observed in Ngb-deficient mice. Ngb expressing neurons which co-stored Gastrin Releasing Peptide (GRP) and were innervated from the eye and the geniculo-hypothalamic tract expressed FOS after light stimulation. No PER1 expression was observed in Ngb-positive neurons. The present study demonstrates for the first time that the genetic elimination of Ngb does not affect core clock function but evokes an increased behavioural response to light concomitant with increased Per1 gene expression in the SCN at early night.

  19. Circadian Behaviour in Neuroglobin Deficient Mice

    PubMed Central

    Hundahl, Christian A.; Fahrenkrug, Jan; Hay-Schmidt, Anders; Georg, Birgitte; Faltoft, Birgitte; Hannibal, Jens

    2012-01-01

    Neuroglobin (Ngb), a neuron-specific oxygen-binding globin with an unknown function, has been proposed to play a key role in neuronal survival. We have previously shown Ngb to be highly expressed in the rat suprachiasmatic nucleus (SCN). The present study addresses the effect of Ngb deficiency on circadian behavior. Ngb-deficient and wild-type (wt) mice were placed in running wheels and their activity rhythms, endogenous period and response to light stimuli were investigated. The effect of Ngb deficiency on the expression of Period1 (Per1) and the immediate early gene Fos was determined after light stimulation at night and the neurochemical phenotype of Ngb expressing neurons in wt mice was characterized. Loss of Ngb function had no effect on overall circadian entrainment, but resulted in a significantly larger phase delay of circadian rhythm upon light stimulation at early night. A light-induced increase in Per1, but not Fos, gene expression was observed in Ngb-deficient mice. Ngb expressing neurons which co-stored Gastrin Releasing Peptide (GRP) and were innervated from the eye and the geniculo-hypothalamic tract expressed FOS after light stimulation. No PER1 expression was observed in Ngb-positive neurons. The present study demonstrates for the first time that the genetic elimination of Ngb does not affect core clock function but evokes an increased behavioural response to light concomitant with increased Per1 gene expression in the SCN at early night. PMID:22496809

  20. Apocynin suppresses the progression of atherosclerosis in apoE-deficient mice by inactivation of macrophages

    SciTech Connect

    Kinoshita, Hiroyuki; Matsumura, Takeshi; Ishii, Norio; Fukuda, Kazuki; Senokuchi, Takafumi; Motoshima, Hiroyuki; Kondo, Tatsuya; Taketa, Kayo; Kawasaki, Shuji; Hanatani, Satoko; Takeya, Motohiro; Nishikawa, Takeshi; Araki, Eiichi

    2013-02-08

    Highlights: ► We examined the anti-athrogenic effect of apocynin in atherosclerotic model mice. ► Apocynin prevented atherosclerotic lesion formation. ► Apocynin suppressed ROS production in aorta and in macrophages. ► Apocynin suppressed cytokine expression and cell proliferation in macrophages. ► Apocynin may be beneficial compound for the prevention of atherosclerosis. -- Abstract: Production of reactive oxygen species (ROS) and other proinflammatory substances by macrophages plays an important role in atherogenesis. Apocynin (4-hydroxy-3-methoxy-acetophenone), which is well known as a NADPH oxidase inhibitor, has anti-inflammatory effects including suppression of the generation of ROS. However, the suppressive effects of apocynin on the progression of atherosclerosis are not clearly understood. Thus, we investigated anti-atherosclerotic effects of apocynin using apolipoprotein E-deficient (apoE{sup –/–}) mice in vivo and in mouse peritoneal macrophages in vitro. In atherosclerosis-prone apoE{sup –/–} mice, apocynin suppressed the progression of atherosclerosis, decreased 4-hydroxynonenal-positive area in atherosclerotic lesions, and mRNA expression of monocyte chemoattractant protein-1 (MCP-1) and interleukin-6 (IL-6) in aorta. In mouse peritoneal macrophages, apocynin suppressed the Ox-LDL-induced ROS generation, mRNA expression of MCP-1, IL-6 and granulocyte/macrophage colony-stimulating factor, and cell proliferation. Moreover, immunohistochemical studies revealed that apocynin decreased the number of proliferating cell nuclear antigen-positive macrophages in atherosclerotic lesions of apoE{sup –/–} mice. These results suggested that apocynin suppressed the formation of atherosclerotic lesions, at least in part, by inactivation of macrophages. Therefore, apocynin may be a potential therapeutic material to prevent the progression of atherosclerosis.

  1. Selenoprotein P and apolipoprotein E receptor-2 interact at the blood-brain barrier and also within the brain to maintain an essential selenium pool that protects against neurodegeneration

    PubMed Central

    Burk, Raymond F.; Hill, Kristina E.; Motley, Amy K.; Winfrey, Virginia P.; Kurokawa, Suguru; Mitchell, Stuart L.; Zhang, Wanqi

    2014-01-01

    Selenoprotein P (Sepp1) and its receptor, apolipoprotein E receptor 2 (apoER2), account for brain retaining selenium better than other tissues. The primary sources of Sepp1 in plasma and brain are hepatocytes and astrocytes, respectively. ApoER2 is expressed in varying amounts by tissues; within the brain it is expressed primarily by neurons. Knockout of Sepp1 or apoER2 lowers brain selenium from ∼120 to ∼50 ng/g and leads to severe neurodegeneration and death in mild selenium deficiency. Interactions of Sepp1 and apoER2 that protect against this injury have not been characterized. We studied Sepp1, apoER2, and brain selenium in knockout mice. Immunocytochemistry showed that apoER2 mediates Sepp1 uptake at the blood-brain barrier. When Sepp1−/− or apoER2−/− mice developed severe neurodegeneration caused by mild selenium deficiency, brain selenium was ∼35 ng/g. In extreme selenium deficiency, however, brain selenium of ∼12 ng/g was tolerated when both Sepp1 and apoER2 were intact in the brain. These findings indicate that tandem Sepp1-apoER2 interactions supply selenium for maintenance of brain neurons. One interaction is at the blood-brain barrier, and the other is within the brain. We postulate that Sepp1 inside the blood-brain barrier is taken up by neurons via apoER2, concentrating brain selenium in them.—Burk, R. F., Hill, K. E., Motley, A. K., Winfrey, V. P., Kurokawa, S., Mitchell, S. L., Zhang, W. Selenoprotein P and apolipoprotein E receptor-2 interact at the blood-brain barrier and also within the brain to maintain an essential selenium pool that protects against neurodegeneration. PMID:24760755

  2. Effect of apolipoprotein E genotype and diet on apolipoprotein E lipidation and amyloid peptides: randomized clinical trial.

    PubMed

    Hanson, Angela J; Bayer-Carter, Jennifer L; Green, Pattie S; Montine, Thomas J; Wilkinson, Charles W; Baker, Laura D; Watson, G Stennis; Bonner, Laura M; Callaghan, Maureen; Leverenz, James B; Tsai, Elaine; Postupna, Nadia; Zhang, Jing; Lampe, Johanna; Craft, Suzanne

    2013-08-01

    Sporadic Alzheimer disease (AD) is caused in part by decreased clearance of the β-amyloid (Aβ) peptide breakdown products. Lipid-depleted (LD) apolipoproteins are less effective at binding and clearing Aβ, and LD Aβ peptides are more toxic to neurons. However, not much is known about the lipid states of these proteins in human cerebrospinal fluid. To characterize the lipidation states of Aβ peptides and apolipoprotein E in the cerebrospinal fluid in adults with respect to cognitive diagnosis and APOE ε4 allele carrier status and after a dietary intervention. Randomized clinical trial. Veterans Affairs Medical Center clinical research unit. Twenty older adults with normal cognition (mean [SD] age, 69 [7] years) and 27 with amnestic mild cognitive impairment (67 [6] years). Randomization to a diet high in saturated fat content and with a high glycemic index (High diet; 45% of energy from fat [>25% saturated fat], 35%-40% from carbohydrates with a mean glycemic index >70, and 15%-20% from protein) or a diet low in saturated fat content and with a low glycemic index (Low diet; 25% of energy from fat [<7% saturated fat], 55%-60% from carbohydrates with a mean glycemic index <55, and 15%-20% from protein). Lipid-depleted Aβ42 and Aβ40 and apolipoprotein E in cerebrospinal fluid. Baseline levels of LD Aβ were greater for adults with mild cognitive impairment compared with adults with normal cognition (LD Aβ42, P = .05; LD Aβ40, P = .01). These findings were magnified in adults with mild cognitive impairment and the ε4 allele, who had higher LD apolipoprotein E levels irrespective of cognitive diagnosis (P < .001). The Low diet tended to decrease LD Aβ levels, whereas the High diet increased these fractions (LD Aβ42, P = .01; LD Aβ40, P = .15). Changes in LD Aβ levels with the Low diet negatively correlated with changes in cerebrospinal fluid levels of insulin (LD Aβ42 and insulin, r = -0.68 [P = .01]; LD Aβ40 and insulin, r = -0.78 [P = .002]). The

  3. Apolipoprotein E Related Co-Morbidities and Alzheimer's Disease.

    PubMed

    Singhrao, Sim K; Harding, Alice; Chukkapalli, Sasanka; Olsen, Ingar; Kesavalu, Lakshmyya; Crean, StJohn

    2016-01-01

    The primary goal of advancement in clinical services is to provide a health care system that enhances an individual's quality of life. Incidence of diabetes mellitus, cardiovascular disease, and associated dementia coupled with the advancing age of the population, have led to an increase in the worldwide challenge to the healthcare system. In order to overcome these challenges, prior knowledge of common, reliable risk factors and their effectors is essential. Oral health constitutes one such relatively unexplored but indispensable risk factor for aforementioned co-morbidities, in the form of poor oral hygiene and tooth loss during aging. Behavioral traits such as low education, smoking, poor diet, neglect of oral health, lack of exercise, and hypertension are few of the risk factors that are shared commonly among these conditions. In addition, common genetic susceptibility traits such as the apolipoprotein E gene, together with an individual's lifestyle can also influence the development of co-morbidities such as periodontitis, atherosclerosis/stroke, diabetes, and Alzheimer's disease. This review specifically addresses the susceptibility of apolipoprotein E gene allele 4 as the plausible commonality for the etiology of co-morbidities that eventually result from periodontal diseases and ultimately progress to dementia.

  4. Constitutive androstane receptor activation decreases plasma apolipoprotein B-containing lipoproteins and atherosclerosis in low-density lipoprotein receptor-deficient mice.

    PubMed

    Sberna, Anne-Laure; Assem, Mahfoud; Xiao, Rui; Ayers, Steve; Gautier, Thomas; Guiu, Boris; Deckert, Valérie; Chevriaux, Angélique; Grober, Jacques; Le Guern, Naig; Pais de Barros, Jean-Paul; Moore, David D; Lagrost, Laurent; Masson, David

    2011-10-01

    The goal of this study was to determine the impact of the nuclear receptor constitutive androstane receptor (CAR) on lipoprotein metabolism and atherosclerosis in hyperlipidemic mice. Low-density lipoprotein receptor-deficient (Ldlr(-/-)) and apolipoprotein E-deficient (ApoE(-/-)) mice fed a Western-type diet were treated weekly with the Car agonist 1,4-bis[2-(3,5-dichloropyridyloxy)]benzene (TCPOBOP) or the vehicle only for 8 weeks. In Ldlr(-/-) mice, treatment with TCPOBOP induced a decrease in plasma triglyceride and intermediate-density lipoprotein/low-density lipoprotein cholesterol levels (≈30% decrease in both cases after 2 months, P<0.01). These mice also showed a significant reduction in the production of very-low-density lipoproteins associated with a decrease in hepatic triglyceride content and the repression of several genes involved in lipogenesis. TCPOBOP treatment also induced a marked increase in the very-low-density lipoprotein receptor in the liver, which probably contributed to the decrease in intermediate-density lipoprotein/low-density lipoprotein levels. Atherosclerotic lesions in the aortic valves of TCPOBOP-treated Ldlr(-/-) mice were also reduced (-60%, P<0.001). In ApoE(-/-) mice, which lack the physiological apoE ligand for the very-low-density lipoprotein receptor, the effect of TCPOBOP on plasma cholesterol levels and the development of atherosclerotic lesions was markedly attenuated. CAR is a potential target in the prevention and treatment of hypercholesterolemia and atherosclerosis.

  5. Angiotensin II infusion promotes ascending aortic aneurysms: attenuation by CCR2 deficiency in apoE−/− mice

    PubMed Central

    Daugherty, Alan; Rateri, Debra L.; Charo, Israel F.; Owens, A. Phillip; Howatt, Deborah A.; Cassis, Lisa A.

    2010-01-01

    AngII (angiotensin II) induces atherosclerosis and AAAs (abdominal aortic aneurysms) through multiple proposed mechanisms, including chemotaxis. Therefore, we determined the effects of whole-body deficiency of the chemokine receptor CCR2 (CC chemokine receptor 2) on these diseases. To meet this objective, apoE (apolipoprotein E)−/− mice that were either CCR2+/+ or CCR2−/−, were infused with either saline or AngII (1000 ng·kg−1 of body weight·min−1) for 28 days via mini-osmotic pumps. Deficiency of CCR2 markedly attenuated both atherosclerosis and AAAs, unrelated to systolic blood pressure or plasma cholesterol concentrations. During the course of the present study, we also observed that AngII infusion led to large dilatations that were restricted to the ascending aortic region of apoE−/− mice. The aortic media in most of the dilated area was thickened. In regions of medial thickening, distinct elastin layers were discernable. There was an expansion of the distance between elastin layers in a gradient from the intimal to the adventitial aspect of the media. This pathology differed in a circumscribed area of the anterior region of ascending aortas in which elastin breaks were focal and almost transmural. All regions of the ascending aorta of AngII-infused mice had diffuse medial macrophage accumulation. Deficiency of CCR2 greatly attenuated the AngII-induced lumen dilatation in the ascending aorta. This new model of ascending aortic aneurysms has pathology that differs markedly from AngII-induced atherosclerosis or AAAs, but all vascular pathologies were attenuated by CCR2 deficiency. PMID:20088827

  6. Mast cell deficiency exacerbates inflammatory bowel symptoms in interleukin-10-deficient mice

    PubMed Central

    Zhang, Hanying; Xue, Yansong; Wang, Hui; Huang, Yan; Du, Min; Yang, Qiyuan; Zhu, Mei-Jun

    2014-01-01

    AIM: To test the role of mast cells in gut inflammation and colitis using interleukin (IL)-10-deficient mice as an experimental model. METHODS: Mast cell-deficient (KitW-sh/W-sh) mice were crossbred with IL-10-deficient mice to obtain double knockout (DKO) mice. The growth, mucosal damage and colitis status of DKO mice were compared with their IL-10-deficient littermates. RESULTS: DKO mice exhibited exacerbated colitis compared with their IL-10-deficient littermates, as shown by increased pathological score, higher myeloperoxidase content, enhanced Th1 type pro-inflammatory cytokines and inflammatory signaling, elevated oxidative stress, as well as pronounced goblet cell loss. In addition, deficiency in mast cells resulted in enhanced mucosal damage, increased gut permeability, and impaired epithelial tight junctions. Mast cell deficiency was also linked to systemic inflammation, as demonstrated by higher serum levels of tumor necrosis factor α and interferon γ in DKO mice than that in IL-10-deficient mice. CONCLUSION: Mast cell deficiency in IL-10-deficient mice resulted in systematic and gut inflammation, impaired gut barrier function, and severer Th1-mediated colitis when compared to mice with only IL-10-deficiency. Inflammation and impaired gut epithelial barrier function likely form a vicious cycle to worsen colitis in the DKO mice. PMID:25083083

  7. Pregnant phenotype in aquaporin 8-deficient mice

    PubMed Central

    Sha, Xiao-yan; Xiong, Zheng-fang; Liu, Hui-shu; Zheng, Zheng; Ma, Tong-hui

    2011-01-01

    Aim: Aquaporin 8 (AQP8) is expressed within the female reproductive system but its physiological function reminds to be elucidated. This study investigates the role of AQP8 during pregnancy using AQP8-knockout (AQP8-KO) mice. Methods: Homozygous AQP8-KO mice were mated, and the conception rate was recorded. AQP8-KO pregnant mice or their offspring were divided into 5 subgroups according to fetal gestational day (7, 13, 16, 18 GD) and newborn. Wild type C57 pregnant mice served as the control group. The number of pregnant mice, total embryos and atrophic embryos, as well as fetal weight, placental weight and placental area were recorded for each subgroup. The amount of amniotic fluid in each sac at 13, 16, and 18 GD was calculated. Statistical significance was determined by analysis of variance of factorial design and chi-square tests. Results: Conception rates did not differ significantly between AQP8-KO and wild type mice. AQP8-KO pregnant mice had a significantly higher number of embryos compared to wild type controls. Fetal/neonatal weight was also significantly greater in the AQP8-KO group compared to age-matched wild type controls. The amount of amniotic fluid was greater in AQP8-KO pregnant mice than wild type controls, although the FM/AFA (fetal weight/amniotic fluid amount) did not differ. While AQP8-KO placental weight was significantly larger than wild type controls, there was no evidence of placental pathology in either group. Conclusion: The results suggest that AQP8 deficiency plays an important role in pregnancy outcome. PMID:21602842

  8. Anagliptin, a DPP-4 inhibitor, suppresses proliferation of vascular smooth muscles and monocyte inflammatory reaction and attenuates atherosclerosis in male apo E-deficient mice.

    PubMed

    Ervinna, Nasib; Mita, Tomoya; Yasunari, Eisuke; Azuma, Kosuke; Tanaka, Rica; Fujimura, Satoshi; Sukmawati, Dewi; Nomiyama, Takashi; Kanazawa, Akio; Kawamori, Ryuzo; Fujitani, Yoshio; Watada, Hirotaka

    2013-03-01

    Dipeptyl peptidase-4 (DPP-4) inhibitors modulate the progression of atherosclerosis. To gain insights into their mechanism of action, 9-wk-old male apolipoprotein E (apoE)-deficient mice were fed a DPP-4 inhibitor, anagliptin-containing diet. The effects of anagliptin were investigated in, a monocyte cell line, human THP-1 cells, and rat smooth muscle cells (SMCs). Treatment with anagliptin for 16 wk significantly reduced accumulation of monocytes and macrophages in the vascular wall, SMC content in plaque areas, and oil red O-stained area around the aortic valve without affecting glucose tolerance or body weight. Serum DPP-4 concentrations were significantly higher in apoE-deficient mice than control mice, and the levels increased with aging, suggesting the involvement of DPP-4 in the progression of atherosclerosis. Indeed, soluble DPP-4 augmented cultured SMC proliferation, and anagliptin suppressed the proliferation by inhibiting ERK phosphorylation. In THP-1 cells, anagliptin reduced lipopolysaccharide-induced TNF-α production with inhibiting ERK phosphorylation and nuclear translocation of nuclear factor-κB. Quantitative analysis also showed that anagliptin reduced the area of atherosclerotic lesion in apoE-deficient mice. These results indicated that the anti-atherosclerotic effect of anagliptin is mediated, at least in part, through its direct inhibition of SMC proliferation and inflammatory reaction of monocytes.

  9. COMMUNICATION: Folate and S-adenosylmethionine modulate synaptic activity in cultured cortical neurons: acute differential impact on normal and apolipoprotein-deficient mice

    NASA Astrophysics Data System (ADS)

    Serra, Michael; Chan, Amy; Dubey, Maya; Gilman, Vladimir; Shea, Thomas B.

    2008-12-01

    Folate deficiency is accompanied by a decline in the cognitive neurotransmitter acetylcholine and a decline in cognitive performance in mice lacking apolipoprotein E (ApoE-/- mice), a low-density lipoprotein that regulates aspects of lipid metabolism. One direct consequence of folate deficiency is a decline in S-adenosylmethionine (SAM). Since dietary SAM supplementation maintains acetylcholine levels and cognitive performance in the absence of folate, we examined herein the impact of folate and SAM on neuronal synaptic activity. Embryonic cortical neurons from mice expressing or lacking ApoE (ApoE+/+ or -/-, respectively) were cultured for 1 month on multi-electrode arrays, and signaling was recorded. ApoE+/+ cultures displayed significantly more frequent spontaneous signals than ApoE-/- cultures. Supplementation with 166 µm SAM (not normally present in culture medium) increased signal frequency and decreased signal amplitude in ApoE+/+ cultures. SAM also increased the frequency of tightly clustered signal bursts. Folate deprivation reversibly reduced signal frequency in ApoE+/+ cultures; SAM supplementation maintained signal frequency despite folate deprivation. These findings support the importance of dietary supplementation with folate and SAM on neuronal health. Supplementation with 166 µm SAM did not alter signaling in ApoE-/- cultures, which may be a reflection of the reduced SAM levels in ApoE-/- mice. The differential impact of SAM on ApoE+/+ and -/- neurons underscores the combined impact of nutritional and genetic deficiencies on neuronal homeostasis.

  10. ApolipoproteinE mimetic peptides improve outcome after focal ischemia.

    PubMed

    Wang, Haichen; Anderson, Lauren G; Lascola, Christopher D; James, Michael L; Venkatraman, Talaignair N; Bennett, Ellen R; Acheson, Shawn K; Vitek, Michael P; Laskowitz, Daniel T

    2013-03-01

    Growing clinical evidence implicates isoform-specific effects of apolipoprotein E (apoE) in reducing neuroinflammation and mediating adaptive responses following ischemic and traumatic brain injury. However, the intact apoE holoprotein does not cross the blood-brain barrier and thus has limited therapeutic potential. We have created a small peptide, COG1410 (acetyl-AS-Aib-LRKL-Aib-KRLL-amide), derived from the apoE receptor-binding region. COG1410 retains the anti-inflammatory and neuroprotective biological properties of the intact holoprotein and penetrates the blood-brain barrier. In the current study, we utilized a murine model of transient focal cerebral ischemia and reperfusion to demonstrate that intravenous (IV) administration of COG1410 reduces infarct volume and radiographic progression of infarct, and improves functional outcome as assessed by rotarod when delivered up to 4h after ischemia onset. Copyright © 2012 Elsevier Inc. All rights reserved.

  11. Apolipoprotein E mediation of neuro-inflammation in a murine model of multiple sclerosis.

    PubMed

    Shin, Soomin; Walz, Katharine A; Archambault, Angela S; Sim, Julia; Bollman, Bryan P; Koenigsknecht-Talboo, Jessica; Cross, Anne H; Holtzman, David M; Wu, Gregory F

    2014-06-15

    Apolipoprotein E (ApoE) functions as a ligand in receptor-mediated endocytosis of lipoprotein particles and has been demonstrated to play a role in antigen presentation. To explore the contribution of ApoE during autoimmune central nervous system (CNS) demyelination, we examined the clinical, cellular immune function, and pathologic consequences of experimental autoimmune encephalomyelitis (EAE) induction in ApoE knockout (ApoE(-/-)) mice. We observed reduced clinical severity of EAE in ApoE(-/-) mice in comparison to WT mice that was concomitant with an early reduction of dendritic cells (DCs) followed by a reduction of additional innate cells in the spinal cord at the peak of disease without any differences in axonal damage. While T cell priming was enhanced in ApoE(-/-) mice, reduced severity of EAE was also observed in ApoE(-/-) recipients of encephalitogenic wild type T cells. Expression of ApoE during EAE was elevated within the CNS of wild type mice, particularly by innate cells such as DCs. Overall, ApoE promotes clinical EAE, likely by mediation of inflammation localized within the CNS. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. The Skeletal Phenotype of Chondroadherin Deficient Mice

    PubMed Central

    Wenglén, Christina; Petzold, Christiane; Tanner, Elizabeth K.; Brorson, Sverre-Henning; Baekkevold, Espen S.; Önnerfjord, Patrik; Reinholt, Finn P.; Heinegård, Dick

    2013-01-01

    Chondroadherin, a leucine rich repeat extracellular matrix protein with functions in cell to matrix interactions, binds cells via their α2β1 integrin as well as via cell surface proteoglycans, providing for different sets of signals to the cell. Additionally, the protein acts as an anchor to the matrix by binding tightly to collagens type I and II as well as type VI. We generated mice with inactivated chondroadherin gene to provide integrated studies of the role of the protein. The null mice presented distinct phenotypes with affected cartilage as well as bone. At 3–6 weeks of age the epiphyseal growth plate was widened most pronounced in the proliferative zone. The proteome of the femoral head articular cartilage at 4 months of age showed some distinct differences, with increased deposition of cartilage intermediate layer protein 1 and fibronectin in the chondroadherin deficient mice, more pronounced in the female. Other proteins show decreased levels in the deficient mice, particularly pronounced for matrilin-1, thrombospondin-1 and notably the members of the α1-antitrypsin family of proteinase inhibitors as well as for a member of the bone morphogenetic protein growth factor family. Thus, cartilage homeostasis is distinctly altered. The bone phenotype was expressed in several ways. The number of bone sialoprotein mRNA expressing cells in the proximal tibial metaphysic was decreased and the osteoid surface was increased possibly indicating a change in mineral metabolism. Micro-CT revealed lower cortical thickness and increased structure model index, i.e. the amount of plates and rods composing the bone trabeculas. The structural changes were paralleled by loss of function, where the null mice showed lower femoral neck failure load and tibial strength during mechanical testing at 4 months of age. The skeletal phenotype points at a role for chondroadherin in both bone and cartilage homeostasis, however, without leading to altered longitudinal growth. PMID

  13. Apolipoprotein E epsilon4 allele and neurobehavioral status after on-pump coronary artery bypass grafting.

    PubMed

    Askar, Fatma Zekiye; Cetin, Hasan Yurday; Kumral, Emre; Cetin, Ozgul; Acarer, Ahmet; Kosova, Buket; Yagdi, Tahir

    2005-01-01

    Abstract Background and Aim: The presence of apolipoprotein E epsilon4 allele is being considered as a risk factor for cognitive decline after cardiac surgery. We sought the effect of apolipoprotein E epsilon4 allele on neurobehavioral status after on-pump coronary artery bypass grafting. Prior to the operation, neurologic examination and neurobehavioral cognitive status test (COGNISTAT) were performed. Both procedures were repeated on the day of discharge and 3 months after surgery. Apolipoprotein E epsilon4 allele positive and apolipoprotein E epsilon4 allele negative patients' performance on COGNISTAT were compared. There was no statistically significant demographic and operative data difference between two groups. No neurological impairment was observed on examinations. There was no statistically significant neurocognitive decline difference between two groups' postoperative performances. It seems that apolipoprotein E epsilon4 allele may not affect neurobehavioral status in the intermediate period after on-pump coronary artery bypass grafting.

  14. A Potential Neuroprotective Role of Apolipoprotein E-containing Lipoproteins through Low Density Lipoprotein Receptor-related Protein 1 in Normal Tension Glaucoma*

    PubMed Central

    Hayashi, Hideki; Eguchi, Yuko; Fukuchi-Nakaishi, Yuko; Takeya, Motohiro; Nakagata, Naomi; Tanaka, Kohichi; Vance, Jean E.; Tanihara, Hidenobu

    2012-01-01

    Glaucoma is an optic neuropathy and the second major cause of blindness worldwide next to cataracts. The protection from retinal ganglion cell (RGC) loss, one of the main characteristics of glaucoma, would be a straightforward treatment for this disorder. However, the clinical application of neuroprotection has not, so far, been successful. Here, we report that apolipoprotein E-containing lipoproteins (E-LPs) protect primary cultured RGCs from Ca2+-dependent, and mitochondrion-mediated, apoptosis induced by glutamate. Binding of E-LPs to the low density lipoprotein receptor-related protein 1 recruited the N-methyl-d-aspartate receptor, blocked intracellular Ca2+ elevation, and inactivated glycogen synthase kinase 3β, thereby inhibiting apoptosis. When compared with contralateral eyes treated with phosphate-buffered saline, intravitreal administration of E-LPs protected against RGC loss in glutamate aspartate transporter-deficient mice, a model of normal tension glaucoma that causes glaucomatous optic neuropathy without elevation of intraocular pressure. Although the presence of α2-macroglobulin, another ligand of the low density lipoprotein receptor-related protein 1, interfered with the neuroprotective effect of E-LPs against glutamate-induced neurotoxicity, the addition of E-LPs overcame the inhibitory effect of α2-macroglobulin. These findings may provide a potential therapeutic strategy for normal tension glaucoma by an LRP1-mediated pathway. PMID:22674573

  15. Cognitive deficits and disruption of neurogenesis in a mouse model of apolipoprotein E4 domain interaction.

    PubMed

    Adeosun, Samuel O; Hou, Xu; Zheng, Baoying; Stockmeier, Craig; Ou, Xiaoming; Paul, Ian; Mosley, Thomas; Weisgraber, Karl; Wang, Jun Ming

    2014-01-31

    Apolipoprotein E4 (apoE4) allele is the major genetic risk factor for sporadic Alzheimer disease (AD) due to the higher prevalence and earlier onset of AD in apoE4 carriers. Accumulating data suggest that the interaction between the N- and the C-terminal domains in the protein may be the main pathologic feature of apoE4. To test this hypothesis, we used Arg-61 mice, a model of apoE4 domain interaction, by introducing the domain interaction feature of human apoE4 into native mouse apoE. We carried out hippocampus-dependent learning and memory tests and related cellular and molecular assays on 12- and 3-month-old Arg-61 and age-matched background C57BL/6J mice. Learning and memory task performance were impaired in Arg-61 mice at both old and young ages compared with C57BL/6J mice. Surprisingly, young Arg-61 mice had more mitotic doublecortin-positive cells in the subgranular zone; mRNA levels of brain-derived neurotrophic factor (BDNF) and TrkB were also higher in 3-month-old Arg-61 hippocampus compared with C57BL/6J mice. These early-age neurotrophic and neurogenic (proliferative) effects in the Arg-61 mouse may be an inadequate compensatory but eventually detrimental attempt by the system to "repair" itself. This is supported by the higher cleaved caspase-3 levels in the young animals that not only persisted, but increased in old age, and the lower levels of doublecortin at old age in the hippocampus of Arg-61 mice. These results are consistent with human apoE4-dependent cognitive and neuro-pathologic changes, supporting the principal role of domain interaction in the pathologic effect of apoE4. Domain interaction is, therefore, a viable therapeutic/prophylactic target for cognitive impairment and AD in apoE4 subjects.

  16. Apolipoprotein E and Alzheimer disease: risk, mechanisms and therapy.

    PubMed

    Liu, Chia-Chen; Liu, Chia-Chan; Kanekiyo, Takahisa; Xu, Huaxi; Bu, Guojun

    2013-02-01

    Apolipoprotein E (Apo-E) is a major cholesterol carrier that supports lipid transport and injury repair in the brain. APOE polymorphic alleles are the main genetic determinants of Alzheimer disease (AD) risk: individuals carrying the ε4 allele are at increased risk of AD compared with those carrying the more common ε3 allele, whereas the ε2 allele decreases risk. Presence of the APOE ε4 allele is also associated with increased risk of cerebral amyloid angiopathy and age-related cognitive decline during normal ageing. Apo-E-lipoproteins bind to several cell-surface receptors to deliver lipids, and also to hydrophobic amyloid-β (Aβ) peptide, which is thought to initiate toxic events that lead to synaptic dysfunction and neurodegeneration in AD. Apo-E isoforms differentially regulate Aβ aggregation and clearance in the brain, and have distinct functions in regulating brain lipid transport, glucose metabolism, neuronal signalling, neuroinflammation, and mitochondrial function. In this Review, we describe current knowledge on Apo-E in the CNS, with a particular emphasis on the clinical and pathological features associated with carriers of different Apo-E isoforms. We also discuss Aβ-dependent and Aβ-independent mechanisms that link Apo-E4 status with AD risk, and consider how to design effective strategies for AD therapy by targeting Apo-E.

  17. Role for apolipoprotein E in neurodegeneration and mercury intoxication.

    PubMed

    Arrifano, Gabriela de Paula Fonseca; de Oliveira, Marcus Augusto; Souza-Monteiro, Jose Rogerio; Paraense, Ricardo Oliveira; Ribeiro-Dos-Santos, Andrea; Vieira, Jose Richardo Dos Santos; Silva, Artur Luis da Costa; Macchi, Barbarella de Matos; do Nascimento, Jose Luiz Martins; Burbano, Rommel Mario Rodriguez; Crespo-Lopez, Maria Elena

    2018-01-01

    Mercury intoxication is a serious public health problem and a worldwide concern. The Minamata Convention on Mercury has been signed by 128 countries and endorsed by the World Health Organization with the recommendation of promoting the management of epidemiological information. The Central Nervous System is the main target organ for mercury. Symptoms of intoxication include altered motor coordination, visual and tactile dysfunction and paralysis, caused by neurodegeneration with a key role for oxidative damage. Recently, some studies have demonstrated a correlation between mercury intoxication and isoforms of apolipoprotein E (ApoE). In this review, epidemiological data and hypotheses about the possible molecular mechanisms underlying the association between ApoE and mercury intoxication are assessed. Based on the evidence and the neuropathological changes that the presence of ApoE4 and mercury neurotoxicity have in common, we propose a convergent action of both factors. ApoE4 seems to potentiate the damage caused by mercury. Increased knowledge of this interaction using epidemiological and pre-clinical studies is essential to improve prevention strategies to adequately manage intoxicated patients.

  18. Apolipoprotein E and Alzheimer disease: risk, mechanisms, and therapy

    PubMed Central

    Liu, Chia-Chen; Kanekiyo, Takahisa; Xu, Huaxi; Bu, Guojun

    2013-01-01

    Apolipoprotein E (ApoE) is a major cholesterol carrier that supports lipid transport and injury repair in the brain. APOE polymorphic alleles are the main genetic determinants of Alzheimer disease (AD) risk: individuals carrying the ε4 allele are at increased risk of AD compared with those carrying the more common ε3 allele, whereas the ε2 allele decreases risk. Presence of the APOE ε4 allele is also associated with increased risk for cerebral amyloid angiopathy and age-related cognitive decline during normal ageing. ApoE–lipoproteins bind to several cell-surface receptors to deliver lipids and also to hydrophobic amyloid-β (Aβ) peptide, which is thought to initiate toxic events that lead to synaptic dysfunction and neurodegeneration in AD. ApoE isoforms differentially regulate Aβ aggregation and clearance in the brain, and have distinct functions in regulating brain lipid transport, glucose metabolism, neuronal signalling, neuroinflammation, and mitochondrial function. In this Review, we describe current knowledge on ApoE in the CNS, with a particular emphasis on the clinical and pathological features associated with carriers of different ApoE isoforms. We also discuss Aβ-dependent and Aβ-independent mechanisms that link ApoE4 status with AD risk, and consider how to design effective strategies for AD therapy by targeting ApoE. PMID:23296339

  19. Prenatal mercury exposure, neurodevelopment and apolipoprotein E genetic polymorphism.

    PubMed

    Snoj Tratnik, Janja; Falnoga, Ingrid; Trdin, Ajda; Mazej, Darja; Fajon, Vesna; Miklavčič, Ana; Kobal, Alfred B; Osredkar, Joško; Sešek Briški, Alenka; Krsnik, Mladen; Neubauer, David; Kodrič, Jana; Stropnik, Staša; Gosar, David; Lešnik Musek, Petra; Marc, Janja; Jurkovič Mlakar, Simona; Petrović, Oleg; Vlašić-Cicvarić, Inge; Prpić, Igor; Milardović, Ana; Radić Nišević, Jelena; Vuković, Danijela; Fišić, Elizabeta; Špirić, Zdravko; Horvat, Milena

    2017-01-01

    The aim of the present study was to evaluate the association between prenatal exposure to mercury (Hg) and neurodevelopment of the child, taking into account genetic polymorphism of apolipoprotein E (Apoe) and other relevant confounders. Six hundred and one mother-child pairs were recruited from the central Slovenia region and 243 from Rijeka, on the Croatian coast of the northern Adriatic. The total Hg in cord blood, Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III) assessment at 18 months of age and Apoe genotyping was performed on 361 children; 237 of them were from Slovenia and 124 from Croatia. The results showed negative association between low-to-moderate Hg exposure in children with normal neurodevelopmental outcome and cognitive and fine motor scores at 18 months of age as assessed by Bayley III. The Hg-related decrease in cognitive score was observed only in children carrying at least one Apoe ε4 allele, while the decrease in fine motor scores was independent of the Apoe genotype. Adjusting for selenium (Se) and lead (Pb) levels, a positive association between Se and the language score and a negative association between Pb and the motor score was observed, but not in the subgroup of children carrying the ε4 allele.

  20. Transgenic Drosophila model to study apolipoprotein E4-induced neurodegeneration.

    PubMed

    Haddadi, Mohammad; Nongthomba, Upendra; Jahromi, Samaneh Reiszadeh; Ramesh, S R

    2016-03-15

    The ε4 isoform of apolipoprotein E (ApoE4) that is involved in neuron-glial lipid metabolism has been demonstrated as the main genetic risk factor in late-onset of Alzheimer's disease. However, the mechanism underlying ApoE4-mediated neurodegeneration remains unclear. We created a transgenic model of neurodegenerative disorder by expressing ε3 and ε4 isoforms of human ApoE in the Drosophila melanogaster. The genetic models exhibited progressive neurodegeneration, shortened lifespan and memory impairment. Genetic interaction studies between amyloid precursor protein and ApoE in axon pathology of the disease revealed that over expression of hApoE in Appl-expressing neurons of Drosophila brain causes neurodegeneration. Moreover, acute oxidative damage in the hApoE transgenic flies triggered a neuroprotective response of hApoE3 while chronic induction of oxidative damage accelerated the rate of neurodegeneration. This Drosophila model may facilitate analysis of the molecular and cellular events implicated in hApoE4 neurotoxicity. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Cerebrovascular effects of apolipoprotein E: implications for Alzheimer disease.

    PubMed

    Zlokovic, Berislav V

    2013-04-01

    Human apolipoprotein E (apoE) has 3 isoforms: apoE2, apoE3, and apoE4. APOE4 is a major genetic risk factor for Alzheimer disease and is associated with dementia in Down syndrome and poor neurological outcome after traumatic brain injury, cerebral hemorrhage, and other neuropathological disorders. While apoE4 can induce neuropathology by participating in various cellular and molecular pathways, herein I review data supporting the hypothesis that apoE4 has direct toxic effects on the cerebrovascular system that in turn can lead to secondary neuronal dysfunction and degeneration as well as accumulation of neurotoxins in brain such as β-amyloid (Aβ) in Alzheimer disease. I review Aβ-independent cerebrovascular effects of apoE, particularly activation of a proinflammatory cyclophilin A-mediated pathway in brain vascular pericytes by apoE4 that has recently been shown to lead to a loss of cerebrovascular integrity and blood-brain barrier breakdown causing neuronal injury. I also review Aβ-dependent cerebrovascular effects of apoE such as faulty Aβ clearance from brain to circulation by apoE4. Finally, I discuss isoform-specific interactions of apoE with low-density lipoprotein receptor-related protein 1 on brain vascular cells (ie, endothelial cells, pericytes), which play an important role in Aβ-independent and Aβ-dependent effects of apoE on cerebral vasculature.

  2. Alzheimer's disease, apolipoprotein E and hormone replacement therapy.

    PubMed

    Depypere, H; Vierin, A; Weyers, S; Sieben, A

    2016-12-01

    Alzheimer's disease is the most frequent cause of dementia in older patients. The prevalence is higher in women than in men. This may be the result of both the higher life expectancy of women and the loss of neuroprotective estrogen after menopause. Earlier age at menopause (spontaneous or surgical) is associated with an enhanced risk of developing Alzheimer's disease. Therefore, it is postulated that estrogen could be protective against it. If so, increasing exposure to estrogen through the use of postmenopausal hormone replacement could also be protective against Alzheimer's disease. The results of the clinical studies that have examined this hypothesis are inconclusive, however. One explanation for this is that estrogen treatment is protective only if it is initiated in the years immediately after menopause. Another possibility is that the neuroprotective effects of estrogen are negated by a particular genotype of apolipoprotein E. This protein plays an important role in cholesterol transport to the neurons. Studies that have examined the link between estrogen replacement therapy, Alzheimer's disease and the E4 allele of ApoE are inconclusive. This article reviews the literature on the influence of hormone replacement therapy on the incidence and progression of Alzheimer's disease.

  3. Genetic Restoration of Plasma ApoE Improves Cognition and Partially Restores Synaptic Defects in ApoE-Deficient Mice.

    PubMed

    Lane-Donovan, Courtney; Wong, Wen Mai; Durakoglugil, Murat S; Wasser, Catherine R; Jiang, Shan; Xian, Xunde; Herz, Joachim

    2016-09-28

    Alzheimer's disease (AD) is the most common form of dementia in individuals over the age of 65 years. The most prevalent genetic risk factor for AD is the ε4 allele of apolipoprotein E (ApoE4), and novel AD treatments that target ApoE are being considered. One unresolved question in ApoE biology is whether ApoE is necessary for healthy brain function. ApoE knock-out (KO) mice have synaptic loss and cognitive dysfunction; however, these findings are complicated by the fact that ApoE knock-out mice have highly elevated plasma lipid levels, which may independently affect brain function. To bypass the effect of ApoE loss on plasma lipids, we generated a novel mouse model that expresses ApoE normally in peripheral tissues, but has severely reduced ApoE in the brain, allowing us to study brain ApoE loss in the context of a normal plasma lipid profile. We found that these brain ApoE knock-out (bEKO) mice had synaptic loss and dysfunction similar to that of ApoE KO mice; however, the bEKO mice did not have the learning and memory impairment observed in ApoE KO mice. Moreover, we found that the memory deficit in the ApoE KO mice was specific to female mice and was fully rescued in female bEKO mice. Furthermore, while the AMPA/NMDA ratio was reduced in ApoE KO mice, it was unchanged in bEKO mice compared with controls. These findings suggest that plasma lipid levels can influence cognition and synaptic function independent of ApoE expression in the brain. One proposed treatment strategy for Alzheimer's disease (AD) is the reduction of ApoE, whose ε4 isoform is the most common genetic risk factor for the disease. A major concern of this strategy is that an animal model of ApoE deficiency, the ApoE knock-out (KO) mouse, has reduced synapses and cognitive impairment; however, these mice also develop dyslipidemia and severe atherosclerosis. Here, we have shown that genetic restoration of plasma ApoE to wild-type levels normalizes plasma lipids in ApoE KO mice. While this does

  4. Apolipoprotein E-Mimetic COG1410 Reduces Acute Vasogenic Edema following Traumatic Brain Injury.

    PubMed

    Cao, Fang; Jiang, Yong; Wu, Yue; Zhong, Jianjun; Liu, Jieshi; Qin, Xinghu; Chen, Ligang; Vitek, Michael P; Li, Fengqiao; Xu, Lu; Sun, Xiaochuan

    2016-01-15

    The degree of post-traumatic brain edema and dysfunction of the blood-brain barrier (BBB) influences the neurofunctional outcome after a traumatic brain injury (TBI). Previous studies have demonstrated that the administration of apolipoprotein E-mimetic peptide COG1410 reduces the brain water content after subarachnoid hemorrhage, intra-cerebral hemorrhage, and focal brain ischemia. However, the effects of COG1410 on vasogenic edema following TBI are not known. The current study evaluated the effects of 1 mg/kg daily COG1410 versus saline administered intravenously after a controlled cortical impact (CCI) injury on BBB dysfunction and vasogenic edema at an acute stage in mice. The results demonstrated that treatment with COG1410 suppressed the activity of matrix metalloproteinase-9, reduced the disruption of the BBB and Evans Blue dye extravasation, reduced the TBI lesion volume and vasogenic edema, and decreased the functional deficits compared with mice treated with vehicle, at an acute stage after CCI. These findings suggest that COG1410 is a promising preclinical therapeutic agent for the treatment of traumatic brain injury.

  5. Apolipoprotein E-Mimetic COG1410 Reduces Acute Vasogenic Edema following Traumatic Brain Injury

    PubMed Central

    Cao, Fang; Wu, Yue; Zhong, Jianjun; Liu, Jieshi; Qin, Xinghu; Chen, Ligang; Vitek, Michael P.; Li, Fengqiao; Xu, Lu

    2016-01-01

    Abstract The degree of post-traumatic brain edema and dysfunction of the blood–brain barrier (BBB) influences the neurofunctional outcome after a traumatic brain injury (TBI). Previous studies have demonstrated that the administration of apolipoprotein E-mimetic peptide COG1410 reduces the brain water content after subarachnoid hemorrhage, intra-cerebral hemorrhage, and focal brain ischemia. However, the effects of COG1410 on vasogenic edema following TBI are not known. The current study evaluated the effects of 1 mg/kg daily COG1410 versus saline administered intravenously after a controlled cortical impact (CCI) injury on BBB dysfunction and vasogenic edema at an acute stage in mice. The results demonstrated that treatment with COG1410 suppressed the activity of matrix metalloproteinase-9, reduced the disruption of the BBB and Evans Blue dye extravasation, reduced the TBI lesion volume and vasogenic edema, and decreased the functional deficits compared with mice treated with vehicle, at an acute stage after CCI. These findings suggest that COG1410 is a promising preclinical therapeutic agent for the treatment of traumatic brain injury. PMID:26192010

  6. Heterogeneous expression of apolipoprotein-E by human macrophages

    PubMed Central

    Tedla, Nicodemus; Glaros, Elias N; Brunk, Ulf T; Jessup, Wendy; Garner, Brett

    2004-01-01

    Apolipoprotein-E (apoE) is expressed at high levels by macrophages. In addition to its role in lipid transport, macrophage-derived apoE plays an important role in immunoregulation. Previous studies have identified macrophage subpopulations that differ substantially in their ability to synthesize specific cytokines and enzymes, however, potential heterogeneous macrophage apoE expression has not been studied. Here we examined apoE expression in human THP-1 macrophages and monocyte-derived macrophages (MDM). Using immunocytochemistry and flow cytometry methods we reveal a striking heterogeneity in macrophage apoE expression in both cell types. In phorbol-ester-differentiated THP-1 macrophages, 5% of the cells over-expressed apoE at levels more than 50-fold higher than the rest of the population. ApoE over-expressing THP-1 macrophages contained condensed/fragmented nuclei and increased levels of activated caspase-3 indicating induction of apoptosis. In MDM, 3–5% of the cells also highly over-expressed apoE, up to 50-fold higher than the rest of the population; however, this was not associated with obvious nuclear alterations. The apoE over-expressing MDM were larger, more granular, and more autofluorescent than the majority of cells and they contained numerous vesicle-like structures that appeared to be coated by apoE. Flow cytometry experiments indicated that the apoE over-expressing subpopulation of MDM were positive for CD14, CD11b/Mac-1 and CD68. These observations suggest that specific macrophage subpopulations may be important for apoE-mediated immunoregulation and clearly indicate that subpopulation heterogeneity should be taken into account when investigating macrophage apoE expression. PMID:15500620

  7. Thyroid hormones upregulate apolipoprotein E gene expression in astrocytes.

    PubMed

    Roman, Corina; Fuior, Elena V; Trusca, Violeta G; Kardassis, Dimitris; Simionescu, Maya; Gafencu, Anca V

    Apolipoprotein E (apoE), a protein mainly involved in lipid metabolism, is associated with several neurodegenerative disorders including Alzheimer's disease. Despite numerous attempts to elucidate apoE gene regulation in the brain, the exact mechanism is still uncovered. The mechanism of apoE gene regulation in the brain involves the proximal promoter and multienhancers ME.1 and ME.2, which evolved by gene duplication. Herein we questioned whether thyroid hormones and their nuclear receptors have a role in apoE gene regulation in astrocytes. Our data showed that thyroid hormones increase apoE gene expression in HTB14 astrocytes in a dose-dependent manner. This effect can be intermediated by the thyroid receptor β (TRβ) which is expressed in these cells. In the presence of triiodothyronine (T3) and 9-cis retinoic acid, in astrocytes transfected to overexpress TRβ and retinoid X receptor α (RXRα), apoE promoter was indirectly activated through the interaction with ME.2. To determine the location of TRβ/RXRα binding site on ME.2, we performed DNA pull down assays and found that TRβ/RXRα complex bound to the region 341-488 of ME.2. This result was confirmed by transient transfection experiments in which a series of 5'- and 3'-deletion mutants of ME.2 were used. These data support the existence of a biologically active TRβ binding site starting at 409 in ME.2. In conclusion, our data revealed that ligand-activated TRβ/RXRα heterodimers bind with high efficiency on tissue-specific distal regulatory element ME.2 and thus modulate apoE gene expression in the brain.

  8. Does Apolipoprotein E Genotype Increase Risk of Postoperative Delirium?

    PubMed Central

    Vasunilashorn, Sarinnapha; Ngo, Long; Kosar, Cyrus M.; Fong, Tamara G.; Jones, Richard N.

    2015-01-01

    Objectives To determine whether Apolipoprotein E (ApoE) is associated with postoperative delirium incidence, severity, and duration in older patients free of dementia at baseline. Design, Setting, Participants We examined 557 non-demented patients age ≥70 undergoing major non-cardiac surgery enrolled in the Successful Aging after Elective Surgery (SAGES) Study. Measurements We considered three ApoE measures: ε2, ε4 carriers vs. non-carriers, and a three-category ApoE measure. Delirium was determined using the Confusion Assessment Method (CAM) and chart review. We used generalized linear models to estimate the association between ApoE and delirium incidence, severity (peak CAM Severity [CAM-S] score), and days. Results ApoE ε2 and ε4 was present in 15% and 19% respectively, and postoperative delirium occurred in 24%. Among patients with delirium, the mean peak CAM-S score was 8.0 (standard deviation 4), with most patients experiencing one or two delirium days (51% or 28%, respectively). After adjusting for age, sex, surgical procedure, and preoperative cognitive function, ApoE ε4 and ε2 carrier status were not associated with postoperative delirium: RR for ε4=1.0, 95% confidence interval (CI) 0.7-1.5 and RR for ε2=0.9, 95% CI 0.6-1.4. No association between ApoE and delirium severity or number of delirium days was observed. Conclusions In older surgery patients free of dementia, our findings do not support the hypothesis that the ApoE genotype does not confer either risk or protection in postoperative delirium incidence, severity, or duration. Thus, an important genetic risk factor for Alzheimer's Disease does not affect risk of delirium. PMID:26238230

  9. Plasma apolipoprotein E and severity of suicidal behaviour.

    PubMed

    Asellus, Peter; Nordström, Peter; Nordström, Anna-Lena; Jokinen, Jussi

    2016-01-15

    There is evidence for association between low cholesterol levels and suicidal behaviour. Since apolipoprotein E (ApoE) is involved in the cholesterol metabolism in both the periphery and in the central nervous system; it may be of particular interest in the neurobiology of suicidal behaviour. Furthermore, hypothalamic-pituitary-adrenal (HPA) axis function, one of the main biological systems implicated in both suicidal behaviour and early-life adversity, affect ApoE levels. Very few studies have assessed plasma ApoE in relation to suicidal behaviour. The purpose of this study was to investigate levels of ApoE in plasma in relation to the severity of suicidal behaviour and life-time adversity in the form of exposure to interpersonal violence in suicide attempters. A total of 100 suicide attempters (67 women and 33 men) were enroled in the study. Information on earlier suicide attempts and age at onset of suicidal behaviour was gathered using the Karolinska Suicide History Interview. The Karolinska Interpersonal Violence Scale was used to assess exposure to interpersonal violence. Plasma ApoE was measured by immunonephelometry according to accredited routines. Patients with at least one earlier suicide attempt had significantly higher ApoE levels compared to suicide attempters debuting with suicidal behaviour at inclusion in the study. A higher number of earlier suicide attempts was significantly correlated with higher plasma ApoE levels. Age at onset was significantly negatively correlated with ApoE after adjusting for age. ApoE showed a significant positive correlation with exposure to interpersonal violence as a child in male suicide attempters. Our findings indicate that ApoE may be related to stress and trauma and the temporal severity of suicidal behaviour.

  10. Apolipoprotein E Mediates Evasion From Hepatitis C Virus Neutralizing Antibodies.

    PubMed

    Fauvelle, Catherine; Felmlee, Daniel J; Crouchet, Emilie; Lee, JiYoung; Heydmann, Laura; Lefèvre, Mathieu; Magri, Andrea; Hiet, Marie-Sophie; Fofana, Isabel; Habersetzer, François; Foung, Steven K H; Milne, Ross; Patel, Arvind H; Vercauteren, Koen; Meuleman, Philip; Zeisel, Mirjam B; Bartenschlager, Ralf; Schuster, Catherine; Baumert, Thomas F

    2016-01-01

    Efforts to develop an effective vaccine against hepatitis C virus (HCV) have been hindered by the propensity of the virus to evade host immune responses. HCV particles in serum and in cell culture associate with lipoproteins, which contribute to viral entry. Lipoprotein association has also been proposed to mediate viral evasion of the humoral immune response, though the mechanisms are poorly defined. We used small interfering RNAs to reduce levels of apolipoprotein E (apoE) in cell culture-derived HCV-producing Huh7.5-derived hepatoma cells and confirmed its depletion by immunoblot analyses of purified viral particles. Before infection of naïve hepatoma cells, we exposed cell culture-derived HCV strains of different genotypes, subtypes, and variants to serum and polyclonal and monoclonal antibodies isolated from patients with chronic HCV infection. We analyzed the interaction of apoE with viral envelope glycoprotein E2 and HCV virions by immunoprecipitation. Through loss-of-function studies on patient-derived HCV variants of several genotypes and subtypes, we found that the HCV particle apoE allows the virus to avoid neutralization by patient-derived antibodies. Functional studies with human monoclonal antiviral antibodies showed that conformational epitopes of envelope glycoprotein E2 domains B and C were exposed after depletion of apoE. The level and conformation of virion-associated apoE affected the ability of the virus to escape neutralization by antibodies. In cell-infection studies, we found that HCV-associated apoE helps the virus avoid neutralization by antibodies against HCV isolated from chronically infected patients. This method of immune evasion poses a challenge for the development of HCV vaccines. Copyright © 2016 AGA Institute. Published by Elsevier Inc. All rights reserved.

  11. Nucleotide sequence and structure of the human apolipoprotein E gene.

    PubMed Central

    Paik, Y K; Chang, D J; Reardon, C A; Davies, G E; Mahley, R W; Taylor, J M

    1985-01-01

    The gene for human apolipoprotein E (apo-E) was selected from a library of cloned genomic DNA by screening with a specific cDNA hybridization probe, and its structure was characterized. The complete nucleotide sequence of the gene as well as 856 nucleotides of the 5' flanking region and 629 nucleotides of the 3' flanking region were determined. Analysis of the sequence showed that the mRNA-encoding region of the apo-E gene consists of four exons separated by three introns. In comparison to the structure of the mRNA, the introns are located in the 5' noncoding region, in the codon for glycine at position -4 of the signal peptide region, and in the codon for arginine at position +61 of the mature protein. The overall lengths of the apo-E gene and its corresponding mRNA are 3597 and 1163 nucleotides, respectively; a mature plasma protein of 299 amino acids is produced by this gene. Examination of the 5' terminus of the gene by S1 nuclease mapping shows apparent multiple transcription initiation sites. The proximal 5' flanking region contains a "TATA box" element as well as two nearby inverted repeat elements. In addition, there are four Alu family sequences associated with the apo-E gene: an Alu sequence located near each end of the gene and two Alu sequences located in the second intron. This knowledge of the structure permits a molecular approach to characterizing the regulation of the apo-E gene. Images PMID:2987927

  12. The distribution of apolipoprotein E alleles in Scottish perinatal deaths

    PubMed Central

    Becher, J‐C; Keeling, J W; McIntosh, N; Wyatt, B; Bell, J

    2006-01-01

    Background The apolipoprotein E (ApoE) polymorphism has been well studied in the adult human population, in part because the e4 allele is a known risk factor for Alzheimer's disease. Little is known of the distribution of ApoE alleles in newborns, and their association with perinatal brain damage has not been investigated. Methods ApoE genotyping was undertaken in a Scottish cohort of perinatal deaths (n = 261), some of whom had prenatal brain damage. The distribution of ApoE alleles in perinatal deaths was compared with that in healthy liveborn infants and in adults in Scotland. Results ApoE e2 was over‐represented in 251 perinatal deaths (13% v 8% in healthy newborns, odds ratio (OR) = 1.63, 95% confidence interval (CI) 1.13 to 2.36 and 13% v 8% in adults, OR = 1.67, 95% CI 1.16 to 2.41), both in liveborn and stillborn perinatal deaths. In contrast, the prevalence of ApoE e4 was raised in healthy liveborn infants (19%) compared with stillbirths (13%, OR = 1.59, 95% CI 1.11 to 2.26) and with adults (15%, OR = 1.35, 95% CI 1.04 to 1.76). However, no correlation was found between ApoE genotype and the presence or absence of perinatal brain damage. Conclusions This study shows a shift in ApoE allelic distribution in early life compared with adults. The raised prevalence of ApoE e2 associated with perinatal death suggests that this allele is detrimental to pregnancy outcome, whereas ApoE e4 may be less so. However, ApoE genotype did not appear to influence the vulnerability for perinatal hypoxic/ischaemic brain damage, in agreement with findings in adult brains and in animal models. PMID:16183800

  13. Rivaroxaban, a novel oral anticoagulant, attenuates atherosclerotic plaque progression and destabilization in ApoE-deficient mice.

    PubMed

    Hara, Tomoya; Fukuda, Daiju; Tanaka, Kimie; Higashikuni, Yasutomi; Hirata, Yoichiro; Nishimoto, Sachiko; Yagi, Shusuke; Yamada, Hirotsugu; Soeki, Takeshi; Wakatsuki, Tetsuzo; Shimabukuro, Michio; Sata, Masataka

    2015-10-01

    Activated factor X (FXa) plays a key role in the coagulation cascade, whereas accumulating evidence suggests that it also contributes to the pathophysiology of chronic inflammation on the vasculature. In this study, we assessed the hypothesis that rivaroxaban (Riv), a direct FXa inhibitor, inhibits atherogenesis by reducing macrophage activation. Expression levels of PAR-1 and PAR-2, receptors for FXa, increased in the aorta of apolipoprotein E-deficient (ApoE(-/-)) mice compared with wild-type mice (P < 0.01, P < 0.05, respectively). Administration of Riv (5 mg/kg/day) for 20 weeks to 8-week-old ApoE(-/-) mice reduced atherosclerotic lesion progression in the aortic arch as determined by en-face Sudan IV staining compared with the non-treated group (P < 0.05) without alteration of plasma lipid levels and blood pressure. Histological analyses demonstrated that Riv significantly decreased lipid deposition, collagen loss, macrophage accumulation and matrix metallopeptidase-9 (MMP-9) expression in atherosclerotic plaques in the aortic root. Quantitative RT-PCR analyses using abdominal aorta revealed that Riv significantly reduced mRNA expression of inflammatory molecules, such as MMP-9, tumor necrosis factor-α (TNF-α). In vitro experiments using mouse peritoneal macrophages or murine macrophage cell line RAW264.7 demonstrated that FXa increased mRNA expression of inflammatory molecules (e.g., interleukin (IL)-1β and TNF-α), which was blocked in the presence of Riv. Riv attenuates atherosclerotic plaque progression and destabilization in ApoE(-/-) mice, at least in part by inhibiting pro-inflammatory activation of macrophages. These results indicate that Riv may be particularly beneficial for the management of atherosclerotic diseases, in addition to its antithrombotic activity. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  14. Mas receptor deficiency is associated with worsening of lipid profile and severe hepatic steatosis in ApoE-knockout mice.

    PubMed

    Silva, Analina R; Aguilar, Edenil C; Alvarez-Leite, Jacqueline I; da Silva, Rafaela F; Arantes, Rosa M E; Bader, Michael; Alenina, Natalia; Pelli, Graziano; Lenglet, Sébastien; Galan, Katia; Montecucco, Fabrizio; Mach, François; Santos, Sérgio H S; Santos, Robson A S

    2013-12-01

    The classical renin-angiotensin system pathway has been recently updated with the identification of additional molecules [such as angiotensin converting enzyme 2, ANG-(1-7), and Mas receptor] that might improve some pathophysiological processes in chronic inflammatory diseases. In the present study, we focused on the potential protective role of Mas receptor activation on mouse lipid profile, liver steatosis, and atherogenesis. Mas/apolipoprotein E (ApoE)-double-knockout (DKO) mice (based on C57BL/6 strain of 20 wk of age) were fed under normal diet and compared with aged-matched Mas and ApoE-single-knockout (KO), as well as wild-type mice. Mas/ApoE double deficiency was associated with increased serum levels of atherogenic fractions of cholesterol, triglycerides, and fasting glucose compared with wild-type or single KO. Serum levels of HDL or leptin in DKO were lower than in other groups. Hepatic lipid content as well as alanine aminotransferase serum levels were increased in DKO compared with wild-type or single-KO animals. Accordingly, the hepatic protein content of mediators related to atherosclerotic inflammation, such as peroxisome proliferator-activated receptor-α and liver X receptor, was altered in an adverse way in DKO compared with ApoE-KO. On the other hand, DKO mice did not display increased atherogenesis and intraplaque inflammation compared with ApoE-KO group. In conclusion, Mas deletion in ApoE-KO mice was associated with development of severe liver steatosis and dyslipidemia without affecting concomitant atherosclerosis. Mas receptor activation might represent promising strategies for future treatments targeting both hepatic and metabolic alterations in chronic conditions clustering these disorders.

  15. Modulating the Gut Microbiota Improves Glucose Tolerance, Lipoprotein Profile and Atherosclerotic Plaque Development in ApoE-Deficient Mice

    PubMed Central

    Rune, Ida; Rolin, Bidda; Larsen, Christian; Nielsen, Dennis Sandris; Kanter, Jenny E.; Bornfeldt, Karin E.; Lykkesfeldt, Jens; Buschard, Karsten; Kirk, Rikke Kaae; Christoffersen, Berit; Fels, Johannes Josef; Josefsen, Knud; Kihl, Pernille; Hansen, Axel Kornerup

    2016-01-01

    The importance of the gut microbiota (GM) in disease development has recently received increased attention, and numerous approaches have been made to better understand this important interplay. For example, metabolites derived from the GM have been shown to promote atherosclerosis, the underlying cause of cardiovascular disease (CVD), and to increase CVD risk factors. Popular interest in the role of the intestine in a variety of disease states has now resulted in a significant proportion of individuals without coeliac disease switching to gluten-free diets. The effect of gluten-free diets on atherosclerosis and cardiovascular risk factors is largely unknown. We therefore investigated the effect of a gluten-free high-fat cholesterol-rich diet, as compared to the same diet in which the gluten peptide gliadin had been added back, on atherosclerosis and several cardiovascular risk factors in apolipoprotein E-deficient (Apoe-/-) mice. The gluten-free diet transiently altered GM composition in these mice, as compared to the gliadin-supplemented diet, but did not alter body weights, glucose tolerance, insulin levels, plasma lipids, or atherosclerosis. In parallel, other Apoe-/- mice fed the same diets were treated with ampicillin, a broad-spectrum antibiotic known to affect GM composition. Ampicillin-treatment had a marked and sustained effect on GM composition, as expected. Furthermore, although ampicillin-treated mice were slightly heavier than controls, ampicillin-treatment transiently improved glucose tolerance both in the absence or presence of gliadin, reduced plasma LDL and VLDL cholesterol levels, and reduced aortic atherosclerotic lesion area. These results demonstrate that a gluten-free diet does not seem to have beneficial effects on atherosclerosis or several CVD risk factors in this mouse model, but that sustained alteration of GM composition with a broad-spectrum antibiotic has beneficial effects on CVD risk factors and atherosclerosis. These findings

  16. Human apolipoprotein E expression in Escherichia coli: structural and functional identity of the bacterially produced protein with plasma apolipoprotein E.

    PubMed Central

    Vogel, T; Weisgraber, K H; Zeevi, M I; Ben-Artzi, H; Levanon, A Z; Rall, S C; Innerarity, T L; Hui, D Y; Taylor, J M; Kanner, D

    1985-01-01

    Human apolipoprotein E (apoE) was produced in Escherichia coli by transforming cells with an expression vector containing a reconstructed apoE cDNA, a lambda PL promoter regulated by the thermolabile cI repressor, and a ribosomal binding site derived from the lambda cII or the E. coli beta-lactamase gene. Transformed cells induced at 42 degrees C for short periods of time (less than 20 min) produced apoE, which accumulated in the cells at levels of approximately equal to 1% of the total soluble cellular protein. Longer induction periods resulted in cell lysis and the proteolytic destruction of apoE. The bacterially produced apoE was purified by heparin-Sepharose affinity chromatography, Sephacryl S-300 gel filtration, and preparative Immobiline isoelectric focusing. The final yield was approximately equal to 20% of the initial apoE present in the cells. Except for an additional methionine at the amino terminus, the bacterially produced apoE was indistinguishable from authentic human plasma apoE as determined by NaDodSO4 and isoelectric focusing gel electrophoresis, amino acid composition of the total protein as well as its cyanogen bromide fragments, and partial amino acid sequence analysis (residues 1-17 and 109-164). Both the bacterially produced and authentic plasma apoE bound similarly to apolipoprotein B,E(low density lipoprotein) receptors of human fibroblasts and to hepatic apoE receptors. Intravenous injection resulted in similar rates of clearance for both the bacterially produced and authentic apoE from rabbit and rat plasma (approximately equal to 50% removed in 20 min). The ability to synthesize a bacterially produced human apolipoprotein with biological properties indistinguishable from those of the native protein will allow the production of large quantities of apoE for use in further investigations of the biological and physiological properties of this apolipoprotein. Images PMID:3909150

  17. An apolipoprotein E-mimetic stimulates axonal regeneration and remyelination after peripheral nerve injury.

    PubMed

    Li, Feng-Qiao; Fowler, Kenneth A; Neil, Jessica E; Colton, Carol A; Vitek, Michael P

    2010-07-01

    Elevated apolipoprotein E (apoE) synthesis within crushed sciatic nerves advocates that apoE could benefit axonal repair and reconstruction of axonal and myelin membranes. We created an apoE-mimetic peptide, COG112 (acetyl-RQIKIWFQNRRMKWKKCLRVRLASHLRKLRKRLL-amide), and found that postinjury treatment with COG112 significantly improved recovery of motor and sensory function following sciatic nerve crush in C57BL/6 mice. Morphometric analysis of injured sciatic nerves revealed that COG112 promoted axonal regrowth after 2 weeks of treatment. More strikingly, the thickness of myelin sheaths was increased by COG112 treatment. Consistent with these histological findings, COG112 potently elevated growth associated protein 43 (GAP-43) and peripheral myelin protein zero (P0), which are markers of axon regeneration and remyelination, respectively. Electron microscopic examination further suggested that the apoE-mimetic COG112 may increase clearance of myelin debris. Schwann cell uptake of cholesterol-containing low-density lipoprotein particles was selectively enhanced by COG112 treatment in a Schwann cell line S16. Moreover, COG112 significantly promoted axon elongation in primary dorsal root ganglion cultures from rat pups. Considering that cholesterol and lipids are needed for reconstructing myelin sheaths and axon extension, these data support a hypothesis where supplementation with exogenous apoE-mimetics such as COG112 may be a promising strategy for restoring lost functional and structural elements following nerve injury.

  18. An Apolipoprotein E-Mimetic Stimulates Axonal Regeneration and Remyelination after Peripheral Nerve Injury

    PubMed Central

    Fowler, Kenneth A.; Neil, Jessica E.; Colton, Carol A.; Vitek, Michael P.

    2010-01-01

    Elevated apolipoprotein E (apoE) synthesis within crushed sciatic nerves advocates that apoE could benefit axonal repair and reconstruction of axonal and myelin membranes. We created an apoE-mimetic peptide, COG112 (acetyl-RQIKIWFQNRRMKWKKCLRVRLASHLRKLRKRLL-amide), and found that postinjury treatment with COG112 significantly improved recovery of motor and sensory function following sciatic nerve crush in C57BL/6 mice. Morphometric analysis of injured sciatic nerves revealed that COG112 promoted axonal regrowth after 2 weeks of treatment. More strikingly, the thickness of myelin sheaths was increased by COG112 treatment. Consistent with these histological findings, COG112 potently elevated growth associated protein 43 (GAP-43) and peripheral myelin protein zero (P0), which are markers of axon regeneration and remyelination, respectively. Electron microscopic examination further suggested that the apoE-mimetic COG112 may increase clearance of myelin debris. Schwann cell uptake of cholesterol-containing low-density lipoprotein particles was selectively enhanced by COG112 treatment in a Schwann cell line S16. Moreover, COG112 significantly promoted axon elongation in primary dorsal root ganglion cultures from rat pups. Considering that cholesterol and lipids are needed for reconstructing myelin sheaths and axon extension, these data support a hypothesis where supplementation with exogenous apoE-mimetics such as COG112 may be a promising strategy for restoring lost functional and structural elements following nerve injury. PMID:20406857

  19. Homocysteine, Another Risk Factor for Alzheimer Disease, Impairs Apolipoprotein E3 Function*

    PubMed Central

    Minagawa, Hirohisa; Watanabe, Atsushi; Akatsu, Hiroyasu; Adachi, Kayo; Ohtsuka, Chigumi; Terayama, Yasuo; Hosono, Takashi; Takahashi, Satoshi; Wakita, Hideaki; Jung, Cha-Gyun; Komano, Hiroto; Michikawa, Makoto

    2010-01-01

    Apolipoprotein E (apoE) ϵ4 and hyperhomocysteinemia are risk factors for Alzheimer disease (AD). The dimerization of apoE3 by disulfide bonds between cysteine residues enhances apoE3 function to generate HDL. Because homocysteine (Hcy) harbors a thiol group, we examined whether Hcy interferes with the dimerization of apoE3 and thereby impairs apoE3 function. We found that Hcy inhibits the dimerization of apoE3 and reduces apoE3-mediated HDL generation to a level similar to that by apoE4, whereas Hcy does not affect apoE4 function. Western blot analysis of cerebrospinal fluid showed that the ratio of apoE3 dimers was significantly lower in the samples from the patients with hyperhomocysteinemia than in those that from control subjects. Hyperhomocysteinemia induced by subcutaneous injection of Hcy to apoE3 knock-in mice decreased the level of the apoE3 dimer in the brain homogenate. Because apoE-HDL plays a role in amyloid β-protein clearance, these results suggest that two different risk factors, apoE4 and hyperhomocysteinemia, may share a common mechanism that accelerates the pathogenesis of AD in terms of reduced HDL generation. PMID:20889503

  20. Effect of human apolipoprotein E genotype on the pathogenesis of experimental ocular HSV-1

    PubMed Central

    Bhattacharjee, Partha S.; Neumann, Donna M.; Foster, Timothy P.; Bouhanik, Sadallah; Clement, Christian; Vinay, Dass; Thompson, Hilary W.; Hill, James M.

    2008-01-01

    The isoform-specific role of human apolipoprotein E (apoE) has been assessed in a mouse model of ocular herpes. Female, age-matched transgenic mice knocked-in for the human allele apoE3 or apoE4 and their parent C57Bl/6 mice were inoculated corneally with HSV-1 strain KOS. Ocular HSV-1 pathogenesis was monitored through viral replication and clinical progression of stromal opacity and neovascularization by slit-lamp examination. Establishment of latency was determined by analysis of HSV-1 DNA (copy number) by specific real-time PCR in the cornea, trigeminal ganglia (TG), and brain. Representative groups of transgenic mice were sacrificed for the analysis of gene expression of vascular endothelial growth factor (VEGF) by reverse-transcription PCR, and apoE expression by Western blot analysis. At 6 days post-infection (P.I.), the ocular infectious HSV-1 titer was significantly higher (p < 0.05) in apoE4 mice compared with apoE3 and C57Bl/6 mice. Corneal neovascularization in apoE4 mice was significantly higher (p < 0.05) than apoE3 and C57Bl/6 mice. The onset of corneal opacity in apoE4 mice was accelerated during days 9--11 P.I.; however, no significant difference in severity was seen on P.I. days 15 and beyond. At 28 days P.I., infected mice of all genotypes had no significant differences in copy numbers (range 0--15) of HSV-1 DNA in their corneas, indicating that HSV-1 DNA copy numbers in cornea are independent of apoE isoform regulation. At 28 days P.I., both apoE4 and C57Bl/6 mice had a significantly higher (p = 0.001) number of copies of HSV-1 DNA in TG compared with apoE3. ApoE4 mice also had significantly higher (p = 0.001) copies of HSV-1 DNA in their TGs compared with C57Bl/6 mice. In brain, both apoE4 and C57Bl/6 mice had significantly higher numbers (p ≤ 0.03) of copies of HSV-1 DNA compared with apoE3 mice. However, the number of HSV-1 DNA copies in the brain of C57Bl/6 mice was not significantly different than that of apoE4 (p = 0.1). Comparative

  1. Nitroglycerin Tolerance in Caveolin-1 Deficient Mice

    PubMed Central

    Mao, Mao; Varadarajan, Sudhahar; Fukai, Tohru; Bakhshi, Farnaz R.; Chernaya, Olga; Dudley, Samuel C.; Minshall, Richard D.; Bonini, Marcelo G.

    2014-01-01

    Nitrate tolerance developed after persistent nitroglycerin (GTN) exposure limits its clinical utility. Previously, we have shown that the vasodilatory action of GTN is dependent on endothelial nitric oxide synthase (eNOS/NOS3) activity. Caveolin-1 (Cav-1) is known to interact with NOS3 on the cytoplasmic side of cholesterol-enriched plasma membrane microdomains (caveolae) and to inhibit NOS3 activity. Loss of Cav-1 expression results in NOS3 hyperactivation and uncoupling, converting NOS3 into a source of superoxide radicals, peroxynitrite, and oxidative stress. Therefore, we hypothesized that nitrate tolerance induced by persistent GTN treatment results from NOS3 dysfunction and vascular toxicity. Exposure to GTN for 48–72 h resulted in nitrosation and depletion (>50%) of Cav-1, NOS3 uncoupling as measured by an increase in peroxynitrite production (>100%), and endothelial toxicity in cultured cells. In the Cav-1 deficient mice, NOS3 dysfunction was accompanied by GTN tolerance (>50% dilation inhibition at low GTN concentrations). In conclusion, GTN tolerance results from Cav-1 modification and depletion by GTN that causes persistent NOS3 activation and uncoupling, preventing it from participating in GTN-medicated vasodilation. PMID:25158065

  2. Apolipoprotein E phenotypes in patients with gout: relation with hypertriglyceridaemia.

    PubMed Central

    Moriwaki, Y; Yamamoto, T; Takahashi, S; Tsutsumi, Z; Higashino, K

    1995-01-01

    OBJECTIVE--To elucidate the relationship, if any, between lipid abnormalities and apolipoprotein E (apo E) polymorphism, by investigating apo E phenotype and allele frequency. METHODS--Fasting blood samples were taken for determination of apo E phenotype and serum lipids in 221 male patients with gout and 141 control male subjects. Apo E phenotype was determined by one dimensional flat gel isoelectric focusing. RESULTS--Frequencies of apo E phenotypes in gout were apo E3/3 67.9%, E4/3 18.1%, E4/4 2.3%, E4/2 1.8%, E3/2 9.5%, and E2/2 0.5%; those in control male subjects were 74.5%, 15.6%, 0%, 1.4%, 7.1%, and 1.4%, respectively. Frequencies of the e2, e3, and e4 alleles in gout were 0.061, 0.817 and 0.122, compared with the corresponding control frequencies of 0.057, 0.858 and 0.085. These differences in apo E phenotype and allele frequencies between gout and control subjects were not significant. The frequency of apo e4 allele in hyperlipidaemic gout subjects was significantly greater than that in normolipidaemic gout subjects; in contrast, its frequency was not different between hyperlipidaemic and normolipidaemic control subjects. Serum triglyceride, total cholesterol, apo B and E concentrations were significantly greater in gouty patients with the apo E4/3 phenotype than in those with gout having the apo E3/3 phenotype. CONCLUSIONS--These data suggest that gout subjects with hyperlipidaemia (hypertriglyceridaemia, hypercholesterolaemia or both) possess the apo e4 allele with higher frequency than those with normolipidaemia. They also suggest that apo e4 may induce some susceptibility to the development of hyperlipidaemia in gout in addition to that induced by obesity or excessive alcohol consumption, and may contribute to the high prevalence of atherosclerotic diseases in gout patients. Images PMID:7794039

  3. Biomarkers Associated With the Apolipoprotein E Genotype and Alzheimer Disease

    PubMed Central

    Soares, Holly D.; Potter, William Z.; Pickering, Eve; Kuhn, Max; Immermann, Frederick W.; Shera, David M; Ferm, Mats; Dean, Robert A.; Simon, Adam J.; Swenson, Frank; Siuciak, Judith A.; Kaplow, June; Thambisetty, Madhav; Zagouras, Panayiotis; Koroshetz, Walter J.; Wan, Hong I.; Trojanowski, John Q.; Shaw, Leslie M.

    2013-01-01

    Background A blood-based test that could be used as a screen for Alzheimer disease (AD) may enable early intervention and better access to treatment. Objective To apply a multiplex immunoassay panel to identify plasma biomarkers of AD using plasma samples from the Alzheimer’s Disease Neuroimaging Initiative cohort. Design Cohort study. Setting The Biomarkers Consortium Alzheimer’s Disease Plasma Proteomics Project. Participants Plasma samples at baseline and at 1 year were analyzed from 396 (345 at 1 year) patients with mild cognitive impairment, 112 (97 at 1 year) patients with AD, and 58 (54 at 1 year) healthy control subjects. Main Outcome Measures Multivariate and univariate statistical analyses were used to examine differences across diagnostic groups and relative to the apolipoprotein E (ApoE) genotype. Results Increased levels of eotaxin 3, pancreatic polypeptide, and N-terminal protein B–type brain natriuretic peptide were observed in patients, confirming similar changes reported in cerebrospinal fluid samples of patients with AD and MCI. Increases in tenascin C levels and decreases in IgM and ApoE levels were also observed. All participants with Apo ε3/ε4 or ε4/ε4 alleles showed a distinct biochemical profile characterized by low C-reactive protein and ApoE levels and by high Cortisol, interleukin 13, apolipoprotein B, and gamma interferon levels. The use of plasma biomarkers improved specificity in differentiating patients with AD from controls, and ApoE plasma levels were lowest in patients whose mild cognitive impairment had progressed to dementia. Conclusions Plasma biomarker results confirm cerebrospinal fluid studies reporting increased levels of pancreatic polypeptide and N-terminal protein B–type brain natriuretic peptide in patients with AD and mild cognitive impairment. Incorporation of plasma biomarkers yielded high sensitivity with improved specificity, supporting their usefulness as a screening tool. The ApoE genotype was

  4. Thyroid hormones upregulate apolipoprotein E gene expression in astrocytes

    SciTech Connect

    Roman, Corina; Fuior, Elena V.; Trusca, Violeta G.; Kardassis, Dimitris; Simionescu, Maya; Gafencu, Anca V.

    2015-12-04

    Apolipoprotein E (apoE), a protein mainly involved in lipid metabolism, is associated with several neurodegenerative disorders including Alzheimer's disease. Despite numerous attempts to elucidate apoE gene regulation in the brain, the exact mechanism is still uncovered. The mechanism of apoE gene regulation in the brain involves the proximal promoter and multienhancers ME.1 and ME.2, which evolved by gene duplication. Herein we questioned whether thyroid hormones and their nuclear receptors have a role in apoE gene regulation in astrocytes. Our data showed that thyroid hormones increase apoE gene expression in HTB14 astrocytes in a dose-dependent manner. This effect can be intermediated by the thyroid receptor β (TRβ) which is expressed in these cells. In the presence of triiodothyronine (T3) and 9-cis retinoic acid, in astrocytes transfected to overexpress TRβ and retinoid X receptor α (RXRα), apoE promoter was indirectly activated through the interaction with ME.2. To determine the location of TRβ/RXRα binding site on ME.2, we performed DNA pull down assays and found that TRβ/RXRα complex bound to the region 341–488 of ME.2. This result was confirmed by transient transfection experiments in which a series of 5′- and 3′-deletion mutants of ME.2 were used. These data support the existence of a biologically active TRβ binding site starting at 409 in ME.2. In conclusion, our data revealed that ligand-activated TRβ/RXRα heterodimers bind with high efficiency on tissue-specific distal regulatory element ME.2 and thus modulate apoE gene expression in the brain. - Highlights: • T3 induce a dose-dependent increase of apoE expression in astrocytes. • Thyroid hormones activate apoE promoter in a cell specific manner. • Ligand activated TRβ/RXRα bind on the distal regulatory element ME.2 to modulate apoE. • The binding site of TRβ/RXRα heterodimer is located at 409 bp on ME.2.

  5. Enhanced contextual fear memory in central serotonin-deficient mice.

    PubMed

    Dai, Jin-Xia; Han, Hui-Li; Tian, Meng; Cao, Jun; Xiu, Jian-Bo; Song, Ning-Ning; Huang, Ying; Xu, Tian-Le; Ding, Yu-Qiang; Xu, Lin

    2008-08-19

    Central serotonin (5-HT) dysregulation contributes to the susceptibility for mental disorders, including depression, anxiety, and posttraumatic stress disorder, and learning and memory deficits. We report that the formation of hippocampus-dependent spatial memory is compromised, but the acquisition and retrieval of contextual fear memory are enhanced, in central 5-HT-deficient mice. Genetic deletion of serotonin in the brain was achieved by inactivating Lmx1b selectively in the raphe nuclei of the brainstem, resulting in a near-complete loss of 5-HT throughout the brain. These 5-HT-deficient mice exhibited no gross abnormality in brain structures and had normal locomotor activity. Spatial learning in the Morris water maze was unaffected, but the retrieval of spatial memory was impaired. In contrast, contextual fear learning and memory induced by foot-shock conditioning was markedly enhanced, but this enhancement could be prevented by intracerebroventricular administration of 5-HT. Foot shock impaired long-term potentiation and facilitated long-term depression in hippocampal slices in WT mice but had no effect in 5-HT-deficient mice. Furthermore, bath application of 5-HT in 5-HT-deficient mice restored foot shock-induced alterations of hippocampal synaptic plasticity. Thus, central 5-HT regulates hippocampus-dependent contextual fear memory, and 5-HT modulation of hippocampal synaptic plasticity may be the underlying mechanism. The enhanced fear memory in 5-HT-deficient mice supports the notion that 5-HT deficiency confers susceptibility to posttraumatic stress disorder in humans.

  6. The Use of L-sIDOL Transgenic Mice as a Murine Model to Study Hypercholesterolemia and Atherosclerosis.

    PubMed

    Zerenturk, Eser J; Calkin, Anna C

    2017-01-01

    There are many advantages to the use of mice as a model to study the regulation of cholesterol metabolism. Common models of hypercholesterolemia include low-density lipoprotein receptor deficient (LDLR -/-) mice and apolipoprotein E deficient (ApoE) -/- mice. Herein, we describe the recently generated mouse model, L-sIDOL Tg mice, which express a dominant active form of Inducible Degrader Of the Low-density lipoprotein receptor (IDOL) in a liver-specific manner. This murine model offers significant advantages over previously established models for the study of hypercholesterolemia and atherosclerosis.

  7. Vitamin D deficiency impairs neurobehavioral development in male mice.

    PubMed

    Fu, Lin; Chen, Yuan-Hua; Chen, Xue; Xu, Shen; Yu, Zhen; Xu, De-Xiang

    2017-10-01

    Vitamin D deficiency is prevalent especially in pregnant women and children. Several studies found that vitamin D status was negatively correlated with risk of senile neurobehavioral abnormality. The aim of this study was to investigate the effects of vitamin D deficiency on neurobehavioral development in mice. In vitamin D deficiency group, dams and their male pups were fed with vitamin D deficient (VDD) diet, in which vitamin D was depleted. Anxiety-related behavior, depressive-like behavior, spatial learning and memory were measured. As expected, serum 25(OH)D level was reduced in VDD diet-fed mice. An anhedonia state, a key depressive-like behavior, was observed in VDD diet-fed mice. In open-field test, peripheral time was decreased and internal time was increased in VDD diet-fed mice. In elevated plus maze, the latency of the first entry into open arms was increased and the number of crossing in open arms was elevated in VDD diet-fed mice. Morris Water Maze showed that VDD-fed mice showed longer escape latency in the first six days. On the seventh day, escape latency was increased in VDD diet-fed mice. These results provide evidence that vitamin D deficiency impairs neurobehavioral development. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Apolipoprotein E4 Elicits Lysosomal Cathepsin D Release, Decreased Thioredoxin-1 Levels, and Apoptosis

    PubMed Central

    Persson, Torbjörn; Lattanzio, Francesca; Calvo-Garrido, Javier; Rimondini, Roberto; Rubio-Rodrigo, Marta; Sundström, Erik; Maioli, Silvia; Sandebring-Matton, Anna; Cedazo-Mínguez, Ángel

    2016-01-01

    The major genetic risk factor for Alzheimer’s disease (AD), apolipoprotein E4 (ApoE4), has been suggested to have detrimental effects on neurons, including direct toxicity via apoptosis. Thioredoxin-1 (Trx1) is an endogenous antioxidant protein important for redox regulation and participates in the regulation of apoptosis through the inhibition of apoptosis signal-regulating kinase-1 (Ask-1). In this study, we have investigated the effects of ApoE on Trx1 in the brain. Our results showed that the protein levels of Trx1 were reduced in the hippocampus of ApoE4 targeted replacement (TR) mice compared to ApoE3 TR mice. The reduction was also seen in vitro after treatment of both human primary cortical neurons and neuroblastoma cells with human recombinant ApoE4 (rApoE4). Furthermore, ApoE4 caused a disruption of lysosomal integrity and a shift in the localization of Cathepsin D, an enzyme known to degrade Trx1. ApoE4 treatment induced in addition apoptosis through translocation of Death-domain associated protein-6 (Daxx) from the nucleus to the cytosol, suggesting an activation of the Ask-1 pathway. This toxicity was prevented by overexpression of Trx1 and other endogenous Ask-1 inhibitors. Our data suggests that down-regulation of Trx1 is involved in the toxicity caused by ApoE4. An activated ASK-1 pathway might indeed make cells more vulnerable to other insults such as amyloid-β, which could partially explain the mechanism behind the strongest genetic risk factor for AD. PMID:28035917

  9. Exacerbated experimental colitis in TNFAIP8-deficient mice.

    PubMed

    Sun, Honghong; Lou, Yunwei; Porturas, Thomas; Morrissey, Samantha; Luo, George; Qi, Ji; Ruan, Qingguo; Shi, Songlin; Chen, Youhai H

    2015-06-15

    The TNF-α-induced protein 8 (TNFAIP8 or TIPE) is a risk factor for cancer and bacterial infection, and its expression is upregulated in a number of human cancers. However, its physiologic and pathologic functions are unclear. In this study, we describe the generation of TIPE-deficient mice and their increased sensitivity to colonic inflammation. TIPE-deficient mice were generated by germ line gene targeting and were born without noticeable developmental abnormalities. Their major organs, including lymphoid organs and intestines, were macroscopically and microscopically normal. However, after drinking dextran sodium sulfate-containing water, TIPE-deficient mice developed more severe colitis than wild type mice did, as demonstrated by decreased survival rates, increased body weight loss, and enhanced leukocyte infiltration, bacterial invasion, and inflammatory cytokine production in the colon. Bone marrow chimeric experiments revealed that TIPE deficiency in nonhematopoietic cells was responsible for the exacerbated colitis in TIPE-deficient mice. Consistent with this result, TIPE-deficient intestinal epithelial cells had increased rate of cell death and decreased rate of proliferation as compared with wild type controls. These findings indicate that TIPE plays an important role in maintaining colon homeostasis and in protecting against colitis.

  10. Exacerbated Experimental Colitis In TNFAIP8-deficient Mice

    PubMed Central

    Sun, Honghong; Lou, Yunwei; Porturas, Thomas; Morrissey, Samantha; Luo, George; Qi, Ji; Ruan, Qingguo; Shi, Songlin; Chen, Youhai H.

    2015-01-01

    The TNF-α-induced protein 8 (TNFAIP8 or TIPE) is a risk factor for cancer and bacterial infection, and its expression is upregulated in a number of human cancers. However, its physiological and pathological functions are unclear. We describe here the generation of TIPE-deficient mice and their increased sensitivity to colonic inflammation. TIPE-deficient mice were generated by germ line gene targeting and were born without noticeable developmental abnormalities. Their major organs including lymphoid organs and intestines were macroscopically and microscopically normal. However, after drinking dextran sodium sulfate-containing water, TIPE-deficient mice developed more severe colitis than wild type mice, as demonstrated by decreased survival rates, increased body weight loss, and enhanced leukocyte infiltration, bacterial invasion, and inflammatory cytokine production in the colon. Bone marrow chimeric experiments revealed that TIPE deficiency in non-hematopoietic cells was responsible for the exacerbated colitis in TIPE-deficient mice. Consistent with this result, TIPE-deficient intestinal epithelial cells had increased rate of cell death and decreased rate of proliferation as compared to wild type controls. Taken together, these findings indicate that TIPE plays an important role in maintaining colon homeostasis and in protecting against colitis. PMID:25948814

  11. Insulin resistance, dyslipidemia, and apolipoprotein E interactions as mechanisms in cognitive impairment and Alzheimer's disease

    PubMed Central

    Salameh, Therese S; Rhea, Elizabeth M; Hanson, Angela J

    2016-01-01

    An increased risk for Alzheimer's disease is associated with dyslipidemia and insulin resistance. A separate literature shows the genetic risk for developing Alzheimer's disease is strongly correlated to the presence of the E4 isoform of the apolipoprotein E carrier protein. Understanding how apolipoprotein E carrier protein, lipids, amyloid β peptides, glucose, central nervous system insulin, and peripheral insulin interact with one another in Alzheimer's disease is an area of increasing interest. Here, we will review the evidence relating apolipoprotein E carrier protein, lipids, and insulin action to Alzheimer's disease and Aβ peptides and then propose mechanisms as to how these factors might interact with one another to impair cognition and promote Alzheimer's disease. PMID:27470930

  12. Increased hippocampal DNA oxidation in serotonin transporter deficient mice.

    PubMed

    Mössner, R; Dringen, R; Persico, A M; Janetzky, B; Okladnova, O; Albert, D; Götz, M; Benninghoff, J; Schmitt, A; Gerlach, M; Riederer, P; Lesch, K P

    2002-05-01

    The serotonin transporter (5HTT) is the molecule responsible for the high-affinity reuptake of 5HT from the synaptic cleft. Mice lacking the 5HTT exhibit highly elevated extracellular concentrations of 5HT. We assessed whether the glutathione detoxification system is altered in 5HTT-deficient mice. While levels of reduced and oxidized glutathione were unchanged, glutathione metabolising enzymes showed a differential pattern of modulation. Glutathione peroxidase was reduced in frontal cortex, brainstem, and cerebellum of 5HTT-deficient mice, though not to a statistically significant extent, while a putative isoform of the detoxifying enzyme glutathione-S-transferase pi was decreased in a number of brain regions, especially in brainstem. At the level of the DNA, we found an increase of oxidative DNA adducts in the hippocampus of 5HTT-deficient mice. Given the importance of the hippocampus in learning and memory, this may be the most important neurochemical consequence of the absence of the 5HTT.

  13. Deficiency of endothelial CXCR4 reduces reendothelialization and enhances neointimal hyperplasia after vascular injury in atherosclerosis-prone mice.

    PubMed

    Noels, Heidi; Zhou, Baixue; Tilstam, Pathricia V; Theelen, Wendy; Li, Xiaofeng; Pawig, Lukas; Schmitz, Corinna; Akhtar, Shamima; Simsekyilmaz, Sakine; Shagdarsuren, Erdenechimeg; Schober, Andreas; Adams, Ralf H; Bernhagen, Jürgen; Liehn, Elisa A; Döring, Yvonne; Weber, Christian

    2014-06-01

    The Cxcl12/Cxcr4 chemokine ligand/receptor axis mediates the mobilization of smooth muscle cell progenitors, driving injury-induced neointimal hyperplasia. This study aimed to investigate the role of endothelial Cxcr4 in neointima formation. β-Galactosidase staining using bone marrow x kinase (Bmx)-CreER(T2) reporter mice and double immunofluorescence revealed an efficient and endothelial-specific deletion of Cxcr4 in Bmx-CreER(T2+) compared with Bmx-CreER(T2-) Cxcr4-floxed apolipoprotein E-deficient (Apoe(-/-)) mice (referred to as Cxcr4(EC-KO)ApoE(-/-) and Cxcr4(EC-WT) ApoE(-/-), respectively). Endothelial Cxcr4 deficiency significantly increased wire injury-induced neointima formation in carotid arteries from Cxcr4(EC-KO)ApoE(-/-) mice. The lesions displayed a higher number of macrophages, whereas the smooth muscle cell and collagen content were reduced. This was associated with a significant reduction in reendothelialization and endothelial cell proliferation in injured Cxcr4(EC-KO)ApoE(-/-) carotids compared with Cxcr4(EC-WT)ApoE(-/-) controls. Furthermore, stimulation of human aortic endothelial cells with chemokine (C-X-C motif) ligand 12 (CXCL12) significantly enhanced their wound-healing capacity in an in vitro scratch assay, an effect that could be reversed with the CXCR4 antagonist AMD3100. Also, flow cytometric analysis showed a reduced mobilization of Sca1(+)Flk1(+)Cd31(+) and of Lin(-)Sca1(+) progenitors in Cxcr4(EC-KO) ApoE(-/-) mice after vascular injury, although Cxcr4 surface expression was unaltered. No differences could be detected in plasma concentrations of Cxcl12, vascular endothelial growth factor, sphingosine 1-phosphate, or Flt3 (fms-related tyrosine kinase 3) ligand, all cytokines with an established role in progenitor cell mobilization. Nonetheless, double immunofluorescence revealed a significant reduction in local endothelial Cxcl12 staining in injured carotids from Cxcr4(EC-KO)ApoE(-/-) mice. Endothelial Cxcr4 is crucial for

  14. Viable offspring obtained from Prm1-deficient sperm in mice

    PubMed Central

    Takeda, Naoki; Yoshinaga, Kazuya; Furushima, Kenryo; Takamune, Kazufumi; Li, Zhenghua; Abe, Shin-ichi; Aizawa, Shin-ichi; Yamamura, Ken-ichi

    2016-01-01

    Protamines are expressed in the spermatid nucleus and allow denser packaging of DNA compared with histones. Disruption of the coding sequence of one allele of either protamine 1 (Prm1) or Prm2 results in failure to produce offspring, although sperm with disrupted Prm1 or Prm2 alleles are produced. Here, we produced Prm1-deficient female chimeric mice carrying Prm1-deficient oocytes. These mice successfully produced Prm1+/− male mice. Healthy Prm1+/− offspring were then produced by transferring blastocysts obtained via in vitro fertilization using zona-free oocytes and sperm from Prm1+/− mice. This result suggests that sperm lacking Prm1 can generate offspring despite being abnormally shaped and having destabilised DNA, decondensed chromatin and a reduction in mitochondrial membrane potential. Nevertheless, these mice showed little derangement of expression profiles. PMID:27250771

  15. Viable offspring obtained from Prm1-deficient sperm in mice.

    PubMed

    Takeda, Naoki; Yoshinaga, Kazuya; Furushima, Kenryo; Takamune, Kazufumi; Li, Zhenghua; Abe, Shin-Ichi; Aizawa, Shin-Ichi; Yamamura, Ken-Ichi

    2016-06-02

    Protamines are expressed in the spermatid nucleus and allow denser packaging of DNA compared with histones. Disruption of the coding sequence of one allele of either protamine 1 (Prm1) or Prm2 results in failure to produce offspring, although sperm with disrupted Prm1 or Prm2 alleles are produced. Here, we produced Prm1-deficient female chimeric mice carrying Prm1-deficient oocytes. These mice successfully produced Prm1(+/-) male mice. Healthy Prm1(+/-) offspring were then produced by transferring blastocysts obtained via in vitro fertilization using zona-free oocytes and sperm from Prm1(+/-) mice. This result suggests that sperm lacking Prm1 can generate offspring despite being abnormally shaped and having destabilised DNA, decondensed chromatin and a reduction in mitochondrial membrane potential. Nevertheless, these mice showed little derangement of expression profiles.

  16. Differential action of glucocorticoids on apolipoprotein E gene expression in macrophages and hepatocytes

    PubMed Central

    Trusca, Violeta Georgeta; Fuior, Elena Valeria; Fenyo, Ioana Madalina; Kardassis, Dimitris; Simionescu, Maya

    2017-01-01

    Apolipoprotein E (apoE) has anti-atherosclerotic properties, being involved in the transport and clearance of cholesterol-rich lipoproteins as well as in cholesterol efflux from cells. We hypothesized that glucocorticoids may exert anti-inflammatory properties by increasing the level of macrophage-derived apoE. Our data showed that glucocorticoids increased apoE expression in macrophages in vitro as well as in vivo. Dexamethasone increased ~6 fold apoE mRNA levels in cultured peritoneal macrophages and RAW 264.7 cells. Administered to C57BL/6J mice, dexamethasone induced a two-fold increase in apoE expression in peritoneal macrophages. By contrast, glucocorticoids did not influence apoE expression in hepatocytes, in vitro and in vivo. Moreover, dexamethasone enhanced apoE promoter transcriptional activity in RAW 264.7 macrophages, but not in HepG2 cells, as tested by transient transfections. Analysis of apoE proximal promoter deletion mutants, complemented by protein-DNA interaction assays demonstrated the functionality of a putative glucocorticoid receptors (GR) binding site predicted by in silico analysis in the -111/-104 region of the human apoE promoter. In hepatocytes, GR can bind to their specific site within apoE promoter but are not able to modulate the gene expression. The modulatory blockade in hepatocytes is a consequence of partial involvement of transcription factors and other signaling molecules activated through MEK1/2 and PLA2/PLC pathways. In conclusion, our study indicates that glucocorticoids (1) differentially target apoE gene expression; (2) induce a significant increase in apoE level specifically in macrophages. The local increase of apoE gene expression in macrophages at the level of the atheromatous plaque may have therapeutic implications in atherosclerosis. PMID:28355284

  17. In Vivo Human Apolipoprotein E Isoform Fractional Turnover Rates in the CNS

    PubMed Central

    Patterson, Bruce W.; Pyatkivskyy, Yuriy; Kim, Jungsu; Yarasheski, Kevin E.; Wang, Jennifer X.; Mawuenyega, Kwasi G.; Jiang, Hong; Parsadanian, Maia; Yoon, Hyejin; Kasten, Tom; Sigurdson, Wendy C.; Xiong, Chengjie; Goate, Alison; Holtzman, David M.; Bateman, Randall J.

    2012-01-01

    Apolipoprotein E (ApoE) is the strongest genetic risk factor for Alzheimer’s disease and has been implicated in the risk for other neurological disorders. The three common ApoE isoforms (ApoE2, E3, and E4) each differ by a single amino acid, with ApoE4 increasing and ApoE2 decreasing the risk of Alzheimer’s disease (AD). Both the isoform and amount of ApoE in the brain modulate AD pathology by altering the extent of amyloid beta (Aβ) peptide deposition. Therefore, quantifying ApoE isoform production and clearance rates may advance our understanding of the role of ApoE in health and disease. To measure the kinetics of ApoE in the central nervous system (CNS), we applied in vivo stable isotope labeling to quantify the fractional turnover rates of ApoE isoforms in 18 cognitively-normal adults and in ApoE3 and ApoE4 targeted-replacement mice. No isoform-specific differences in CNS ApoE3 and ApoE4 turnover rates were observed when measured in human CSF or mouse brain. However, CNS and peripheral ApoE isoform turnover rates differed substantially, which is consistent with previous reports and suggests that the pathways responsible for ApoE metabolism are different in the CNS and the periphery. We also demonstrate a slower turnover rate for CSF ApoE than that for amyloid beta, another molecule critically important in AD pathogenesis. PMID:22675504

  18. True Niacin Deficiency in Quinolinic Acid Phosphoribosyltransferase (QPRT) Knockout Mice.

    PubMed

    Shibata, Katsumi

    2015-01-01

    Pyridine nucleotide coenzymes (PNCs) are involved in over 500 enzyme reactions. PNCs are biosynthesized from the amino acid L-tryptophan (L-Trp), as well as the vitamin niacin. Hence, "true" niacin-deficient animals cannot be "created" using nutritional techniques. We wanted to establish a truly niacin-deficient model animal using a protocol that did not involve manipulating dietary L-Trp. We generated mice that are missing the quinolinic acid phosphoribosyltransferase (QPRT) gene. QPRT activity was not detected in qprt(-/-)mice. The qprt(+/+), qprt(+/-) or qprt(-/-) mice (8 wk old) were fed a complete diet containing 30 mg nicotinic acid (NiA) and 2.3 g L-Trp/kg diet or an NiA-free diet containing 2.3 g L-Trp/kg diet for 23 d. When qprt(-/-)mice were fed a complete diet, food intake and body weight gain did not differ from those of the qprt(+/+) and the qprt(+/-) mice. On the other hand, in the qprt(-/-) mice fed the NiA-free diet, food intake and body weight were reduced to 60% (p<0.01) and 70% (p<0.05) of the corresponding values for the qprt(-/-) mice fed the complete diet at day 23, respectively. The nutritional levels of niacin such as blood and liver NAD concentrations were also lower in the qprt(-/-) mice than in the qprt(+/+) and the qprt(+/-) mice. Urinary excretion of quinolinic acid was greater in the qprt(-/-) mice than in the qprt(+/+) and the qprt(+/-) mice (p<0.01). These data suggest that we generated truly niacin-deficient mice.

  19. Behavioral analysis of relaxin-3 deficient mice.

    PubMed

    Tanaka, Masaki; Furube, Eriko; Aoki, Miku; Watanabe, Yoshihisa

    2013-01-01

    Relaxin-3 is a neuropeptide belonging to the relaxin/insulin superfamily. Studies using rodents have revealed that relaxin-3 is predominantly expressed in neurons in the nucleus incertus of the pons, projecting axons to forebrain regions including the hypothalamus. There is evidence that relaxin-3 is involved in several functions, including food intake and stress responses. We generated relaxin-3 gene knockout (KO) mice and examined them using a battery of behavioral tests of sensory/motor functions and emotion-related behaviors. Relaxin-3 KO mice exhibited normal growth and appearance. There was no difference in bodyweight among genotypes in both normal and high fat diet feeding. In addition, there were no significant differences between wild-type and KO mice in social interaction, depression-like behavior, and short memory test. However, in the elevated plus maze test, KO mice exhibited a robust increase in the tendency to enter open arms, although they exhibited normal performance in a light/dark transition test and showed no difference from wild-type mice in the open field test. Taken together, these results indicate that relaxin-3 KO mice exhibit mild anxiolytic characteristics relative to wild-type mice, suggesting that this peptide is involved in anxiety-related behavior.

  20. Aorta Atherosclerosis Lesion Analysis in Hyperlipidemic Mice

    PubMed Central

    Mohanta, Sarajo; Yin, Changjun; Weber, Christian; Hu, Desheng; Habenicht, Andreas JR

    2016-01-01

    Atherosclerosis is a chronic inflammatory disease of large and medium-sized arteries. Apolipoprotein E-deficient (ApoE-/-) mice are used as experimental models to study human atherosclerosis. ApoE-/- mice are constitutively hyperlipidemic and develop intima plaques that resemble human plaques. Various issues including experimental design for lesion analysis, dietary conditions, isolation of the aorta, staining methods, morphometry, group size, age, the location within the arterial tree, and statistical analyses are important parameters that need to be addressed to obtain robust data. Here, we provide detailed methods to quantify aorta atherosclerosis. PMID:27366759

  1. Left-Sided Cardiac Valvulitis in Tristetraprolin-Deficient Mice

    PubMed Central

    Ghosh, Sanjukta; Hoenerhoff, Mark J.; Clayton, Natasha; Myers, Page; Stumpo, Deborah J.; Maronpot, Robert R.; Blackshear, Perry J.

    2010-01-01

    Inflammation may play a role in the etiology of both degenerative and rheumatic cardiac valve diseases. We report here that mice deficient in tristetraprolin (TTP), a protein with known anti-inflammatory functions, develop severe left-sided cardiac valvulitis. TTP is an mRNA binding protein that inhibits inflammation by destabilizing the mRNA encoding tumor necrosis factor α (TNF). This leads in turn to a TNF-excess syndrome characterized by systemic inflammation. Evaluation of hearts from TTP−/− mice demonstrated gross thickening of the mitral and aortic but not the tricuspid or pulmonary valves, accompanied by inflammatory cell infiltrates. To determine whether TNF played a role in the development of this valvulitis, we examined mice deficient in both TNF receptors and in TTP; four of five of these mice exhibited no histological evidence of valvulitis, but one mouse had aortic valve leaflet thickening with a cellular infiltrate. Four additional mice had no external evidence of valvular thickening. Cardiac valves of transgenic mice expressing human TNF developed mild aortic valve leaflet edema without evidence of hypercellularity. Thus, TTP deficiency in mice leads to left-sided cardiac valvulitis with prominent inflammatory cell involvement, due, at least in part, to excess TNF. These findings support the potential involvement of TNF and inflammation in the development of cardiac valve disease in man. PMID:20093488

  2. Does Possession of Apolipoprotein E[superscript E]4 Benefit Cognitive Function in Healthy Young Adults?

    ERIC Educational Resources Information Center

    Bunce, David; Anstey, Kaarin J.; Burns, Richard; Christensen, Helen; Easteal, Simon

    2011-01-01

    There is considerable evidence that the apolipoprotein E (APOE)[superscript E]4 allele is associated with cognitive deficits in older persons, and is a risk factor for dementia. However, it has recently been suggested that possession of the [superscript E]4 allele may benefit cognition in early adulthood. We tested this possibility in 5445…

  3. Apolipoprotein E gene polymorphisms and retinal vascular signs: The Atherosclerosis Risk in Communities (ARIC) Study

    USDA-ARS?s Scientific Manuscript database

    Our objective was to examine the association between apolipoprotein E (APOE) gene polymorphisms and retinal microvascular signs. We used a population-based, cross-sectional study. Participants from the Atherosclerosis Risk in Communities Study (n=10,036; aged 49-73 years) had retinal photographs tak...

  4. Copper deficiency in neonatal mice alters brain catecholamine levels

    SciTech Connect

    Bailey, W.R.; Prohaska, J.R. )

    1991-03-15

    Copper (Cu) deficiency was investigated in Swiss albino mice to develop a model that alters brain catecholamine metabolism without serious growth impairment. Cu deficiency was induced by feeding a diet low in Cu to dams beginning either 7 days (d) prior, 4d prior, 4d after, or on the day of parturition. All 4-week-old male Cu-deficient ({minus}Cu) offspring were anemic and exhibited biochemical characteristics of Cu deficiency when compared to their respective +Cu control mice. However, the best model, which resulted in altered catecholamine metabolism characterized by elevation of dopamine (DA) and depression in norepinephrine (NE) in brain, heart, and spleen, was when treatment began 4d prior to birth. Body and brain weight were not altered. However, levels of Cu in brain and liver of {minus}Cu mice were markedly reduced to 21% and 31% of those measured in +Cu controls, respectively. Furthermore, brain NE and DA concentrations of {minus}Cu mice were 72% and 132% of those quantified in +Cu offspring, respectively. A plausible explanation is that dietary Cu deficiency results in lower activity of brain dopamine-{beta}-monooxygenase, the Cu dependent enzyme that catalyzes conversion of DA to NE. It is not yet known if these changes in Ne and DA pool size altered the quantity or characteristics of the neuronal catecholamine receptors, and more importantly, whether or not the observed changes are reversible by nutritional intervention.

  5. Behavioral Defects in Chaperone-Deficient Alzheimer's Disease Model Mice

    PubMed Central

    Ojha, Juhi; Karmegam, Rajalakshmi V.; Masilamoni, J. Gunasingh; Terry, Alvin V.; Cashikar, Anil G.

    2011-01-01

    Molecular chaperones protect cells from the deleterious effects of protein misfolding and aggregation. Neurotoxicity of amyloid-beta (Aβ) aggregates and their deposition in senile plaques are hallmarks of Alzheimer's disease (AD). We observed that the overall content of αB-crystallin, a small heat shock protein molecular chaperone, decreased in AD model mice in an age-dependent manner. We hypothesized that αB-crystallin protects cells against Aβ toxicity. To test this, we crossed αB-crystallin/HspB2 deficient (CRYAB-/-HSPB2-/-) mice with AD model transgenic mice expressing mutant human amyloid precursor protein. Transgenic and non-transgenic mice in chaperone-sufficient or deficient backgrounds were examined for representative behavioral paradigms for locomotion and memory network functions: (i) spatial orientation and locomotion was monitored by open field test; (ii) sequential organization and associative learning was monitored by fear conditioning; and (iii) evoked behavioral response was tested by hot plate method. Interestingly, αB-crystallin/HspB2 deficient transgenic mice were severely impaired in locomotion compared to each genetic model separately. Our results highlight a synergistic effect of combining chaperone deficiency in a transgenic mouse model for AD underscoring an important role for chaperones in protein misfolding diseases. PMID:21379584

  6. Behavioral defects in chaperone-deficient Alzheimer's disease model mice.

    PubMed

    Ojha, Juhi; Karmegam, Rajalakshmi V; Masilamoni, J Gunasingh; Terry, Alvin V; Cashikar, Anil G

    2011-02-17

    Molecular chaperones protect cells from the deleterious effects of protein misfolding and aggregation. Neurotoxicity of amyloid-beta (Aβ) aggregates and their deposition in senile plaques are hallmarks of Alzheimer's disease (AD). We observed that the overall content of αB-crystallin, a small heat shock protein molecular chaperone, decreased in AD model mice in an age-dependent manner. We hypothesized that αB-crystallin protects cells against Aβ toxicity. To test this, we crossed αB-crystallin/HspB2 deficient (CRYAB⁻/⁻HSPB2⁻/⁻) mice with AD model transgenic mice expressing mutant human amyloid precursor protein. Transgenic and non-transgenic mice in chaperone-sufficient or deficient backgrounds were examined for representative behavioral paradigms for locomotion and memory network functions: (i) spatial orientation and locomotion was monitored by open field test; (ii) sequential organization and associative learning was monitored by fear conditioning; and (iii) evoked behavioral response was tested by hot plate method. Interestingly, αB-crystallin/HspB2 deficient transgenic mice were severely impaired in locomotion compared to each genetic model separately. Our results highlight a synergistic effect of combining chaperone deficiency in a transgenic mouse model for AD underscoring an important role for chaperones in protein misfolding diseases.

  7. Herpes simplex virus type 1 infection via the bloodstream with apolipoprotein E dependence in the gonads is influenced by gender.

    PubMed

    Burgos, Javier S; Ramirez, Carlos; Sastre, Isabel; Alfaro, Juan M; Valdivieso, Fernando

    2005-02-01

    Herpes simplex virus type 1 (HSV-1) causes disease in humans and animals. Infection usually occurs via the neural route and possibly occurs via the hematogenous route. The latter, however, is the main route by which immunosuppressed individuals and neonates are infected. Gender-dependent differences in the incidence and severity of some viral infections have been reported. To detect differences between the sexes with respect to HSV-1 colonization and disease, the characteristics of both acute and latent infections in hematogenously infected male and female mice were compared. In acute infection, the female mice had a poorer outcome: HSV-1 colonization was more effective, especially in the gonads and brain. In the encephalon, the midbrain had the highest viral load. In latent infection, brain viral loads were not significantly different with respect to sex. Significant differences were seen, however, in the blood and trigeminal ganglia: HSV-1 seroprevalence was observed in females, with no virus detected in males. In brain dissections, only the cerebral cortex of the females had viral loads statistically higher than those observed in the males. The spread of the virus to several organs of interest during acute infection was examined immunohistochemically. Female mice showed greater viral immunostaining, especially in the adrenal cortex, gonads, and midbrain. In male mice, HSV-1 was detected predominantly in the adrenal cortex. It was also found that apolipoprotein E promotes virus colonization of the ovaries, the APOE gene dose being directly related to viral invasiveness.

  8. USE OF FUSED CIRCULATIONS TO INVESTIGATE THE ROLE OF APOLIPOPROTEIN E AS AMYLOID CATALYST AND PERIPHERAL SINK IN ALZHEIMER'S DISEASE

    PubMed Central

    Nilsson, Lars N. G.; Gografe, Sylvia; Costa, David A.; Hughes, Tiffany; Dressler, David; Potter, Huntington

    2013-01-01

    Apolipoprotein E (apoE) synthesized in liver and brain plays a key role in both cholesterol transport and Alzheimer's disease (AD): apoE-knockout mice develop hypercholesterolemia and atherosclerosis and cannot support AD amyloid deposition. The ApoE4 allele is the strongest genetic risk factor for late-onset AD, and apoE4 protein preferentially catalyzes amyloid-beta (Aβ) peptide fibrillization in vitro and amyloid plaque deposition in vivo. Circulating apoE may also have the potential to draw Aβ from the brain and reduce amyloid deposition. We used parabiosis to determine how circulating apoE impacts brain amyloid deposition and blood cholesterol levels in transgenic mice carrying AD-promoting APP and PS1 human transgenes—either with or without the endogenous mouse apoE gene. ApoE transferred through the joined circulations from WT to parabiosed APP+/+,PS1+/−,apoE-KO mice prevented hypercholesterolemia and reduced already low brain amyloid deposition. The findings indicate that apoE synthesis in the brain itself is necessary for amyloid accumulation. Furthermore, plasma apoE can both normalize cholesterol levels in apoE-KO mice and act as a peripheral sink to induce net efflux of Aβ peptide from the brain. The therapeutic implication is that inhibiting Alzheimer's disease neuropathology may be accomplished by either reducing apoE in the brain or increasing apoE in the blood. PMID:23626867

  9. Folate Deficiency Could Restrain Decidual Angiogenesis in Pregnant Mice

    PubMed Central

    Li, Yanli; Gao, Rufei; Liu, Xueqing; Chen, Xuemei; Liao, Xinggui; Geng, Yanqing; Ding, Yubin; Wang, Yingxiong; He, Junlin

    2015-01-01

    The mechanism of birth defects induced by folate deficiency was focused on mainly in fetal development. Little is known about the effect of folate deficiency on the maternal uterus, especially on decidual angiogenesis after implantation which establishes vessel networks to support embryo development. The aim of this study was to investigate the effects of folate deficiency on decidual angiogenesis. Serum folate levels were measured by electrochemiluminescence. The status of decidual angiogenesis was examined by cluster designation 34 (CD34) immunohistochemistry and the expression of angiogenic factors, including vascular endothelial growth factor A (VEGFA), placental growth factor (PLGF), and VEGF receptor 2 (VEGFR2) were also tested. Serum levels of homocysteine (Hcy), follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), progesterone (P4), and estradiol (E2) were detected by Enzyme-linked immunosorbent assay. The folate-deficient mice had a lower folate level and a higher Hcy level. Folate deficiency restrained decidual angiogenesis with significant abnormalities in vascular density and the enlargement and elongation of the vascular sinus. It also showed a reduction in the expressions of VEGFA, VEGFR2, and PLGF. In addition, the serum levels of P4, E2, LH, and PRL were reduced in folate-deficient mice, and the expression of progesterone receptor (PR) and estrogen receptor α (ERα) were abnormal. These results indicated that folate deficiency could impaire decidual angiogenesis and it may be related to the vasculotoxic properties of Hcy and the imbalance of the reproductive hormone. PMID:26247969

  10. Folate Deficiency Could Restrain Decidual Angiogenesis in Pregnant Mice.

    PubMed

    Li, Yanli; Gao, Rufei; Liu, Xueqing; Chen, Xuemei; Liao, Xinggui; Geng, Yanqing; Ding, Yubin; Wang, Yingxiong; He, Junlin

    2015-08-04

    The mechanism of birth defects induced by folate deficiency was focused on mainly in fetal development. Little is known about the effect of folate deficiency on the maternal uterus, especially on decidual angiogenesis after implantation which establishes vessel networks to support embryo development. The aim of this study was to investigate the effects of folate deficiency on decidual angiogenesis. Serum folate levels were measured by electrochemiluminescence. The status of decidual angiogenesis was examined by cluster designation 34 (CD34) immunohistochemistry and the expression of angiogenic factors, including vascular endothelial growth factor A (VEGFA), placental growth factor (PLGF), and VEGF receptor 2 (VEGFR2) were also tested. Serum levels of homocysteine (Hcy), follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), progesterone (P4), and estradiol (E2) were detected by Enzyme-linked immunosorbent assay. The folate-deficient mice had a lower folate level and a higher Hcy level. Folate deficiency restrained decidual angiogenesis with significant abnormalities in vascular density and the enlargement and elongation of the vascular sinus. It also showed a reduction in the expressions of VEGFA, VEGFR2, and PLGF. In addition, the serum levels of P4, E2, LH, and PRL were reduced in folate-deficient mice, and the expression of progesterone receptor (PR) and estrogen receptor α (ERα) were abnormal. These results indicated that folate deficiency could impaire decidual angiogenesis and it may be related to the vasculotoxic properties of Hcy and the imbalance of the reproductive hormone.

  11. Phosphorylase kinase isoenzymes in deficient ICR/IAn mice.

    PubMed

    Daegelen-Proux, D; Alexandre, Y; Dreyfus, J C

    1978-10-01

    ICR/IAn mice present a deficiency in phosphorylase kinase activity; the extent of this deficiency is less in some tissues [Lyon, S.B. Biochem. Genet. 4, 169--185 (1970)] than in skeletal muscle, where enzyme activity is 0.3% of normal [Cohen, P.T. W & Cohen, P. FEBS Lett. 29, 113--115 (1973)]. New-born mice of this strain were also reported (Lyon, 1970) to reveal a small amount of skeletal muscle enzyme activity. The properties of these residual phosphorylase kinases were compared to those of control C57 BL mice, with reference to control muscle and liver enzymes which were shown to be of different molecular species [Daegelen-Proux et al. Biochim. Biophys Acta, 452, 398--405 (1976)]. The properties investigated were the immunological reactivity against an antiserum raised against muscle phosphorylase kinase, the thermal stability and the Ca2+ dependency. The results suggest that the muscle enzyme from the new-born ICR/IAn mice and the heart enzyme from adult deficient mice are different to the muscle enzyme from adult normal mice, but they have properties in common with normal adult liver enzyme. These results lead to the conclusion that there exists in the muscle of I strain a "foetal form" of phosphorylase kinase, the activity of which decreases progressively after birth. Out work also confirmed the observations made by Cohen et al. [Eur. J. Biochem. 66, 347--356 (1976)] which showed that there is no evidence for the existence of a cross-reacting material in the muscle of adult deficient mice.

  12. Calmodulin-like skin protein is downregulated in human cerebrospinal fluids of Alzheimer's disease patients with apolipoprotein E4; a pilot study using postmortem samples.

    PubMed

    Hashimoto, Yuichi; Umahara, Takahiko; Hanyu, Haruo; Iwamoto, Toshihiko; Matsuoka, Masaaki

    2017-09-01

    Calmodulin-like skin protein (CLSP) is a secreted peptide that inhibits neuronal cell death, linked to Alzheimer's disease (AD), by binding to the heterotrimeric humanin receptor and activating an intracellular survival pathway. CLSP is only expressed in skin keratinocytes and related epithelial cells, circulates in the blood stream, and passes the blood-cerebrospinal fluid (CSF) barrier. In the current study, we addressed the issues as to whether CLSP functions in the central nervous system and whether the concentration of CLSP is reduced in the CSFs of AD patients. Mice were intraperitoneally injected with 5 nmol of recombinant human CLSP. At 1h after the injection, the mice were sacrificed for the analysis of the existence of human CLSP in blood and interstitial fluid (ISF)-containing brain samples. Using postmortem CSF samples, we next determined the concentrations of CLSP in CSFs of human AD and control cases. Intraperitoneally administered recombinant human CLSP circulated in the blood stream and reached the brain interstitial fluid. The concentrations of CLSP in CSFs of human AD and control cases are sufficient to exhibit the CLSP activity. Although the concentrations of CLSP in CSFs were not significantly different between AD and control cases, the concentrations of CLSP are lower in the AD cases with the apolipoprotein E4 genotype than in the AD cases without the apolipoprotein E4 genotype. The first result indicates that CLSP enters the central nervous system through the blood-brain barrier. The second result suggests that CLSP functions in the human brains. The third result may exclude the possibility that the downregulation of the CLSP level is involved in the AD pathogenesis. The last result may contribute to the better understanding of the AD pathogenesis from the standpoint of the apolipoprotein E genotype.

  13. Kidney histologic alterations in α-Galactosidase-deficient mice.

    PubMed

    Valbuena, Carmen; Oliveira, João Paulo; Carneiro, Fátima; Relvas, Sandra; Ganhão, Mariana; Sá-Miranda, M Clara; Rodrigues, Lorena G

    2011-04-01

    Fabry disease is a rare X-linked disorder caused by mutations in the α-galactosidase gene (GLA), the resultant deficiency of lysosomal α-galactosidase enzyme activity leading to systemic accumulation of globotriaosylceramide and other glycosphingolipids. GLA knockout mice ("Fabry mice") were generated as an animal model for Fabry disease but, as they do not manifest progressive chronic kidney disease (CKD), their relevance as a model for human Fabry nephropathy is uncertain. We evaluated the histological alterations in the kidneys of Fabry mice at different ages, as contrasted to those observed in wild-type mice. Furthermore, we compared the renal histological alterations of Fabry mice to the kidney pathology reported in patients with Fabry disease at comparable age ranges and across different CKD stages, using a scoring system that has been developed for Fabry nephropathy. Fabry mice are phenotypically different from wild-type mice, displaying progressive age-related accumulation of glycosphingolipids in all types of renal cells. There were no statistically significant differences between Fabry mice and Fabry patients in the prevalence of glycosphingolipid storage per renal cell type with the exceptions of mesangial (higher in humans) and proximal tubular cells (higher in mice). However, Fabry mice lack the nonspecific histological glomerulosclerotic and interstitial fibrotic renal lesions that best correlate with progressive CKD in Fabry patients, and do not develop large podocyte inclusions. We postulate that the elucidation of the mechanisms underlying these species differences, may contribute important clues to a better understanding of the pathogenesis of Fabry nephropathy.

  14. Serotonin Deficiency Exacerbates Acetaminophen-Induced Liver Toxicity In Mice

    PubMed Central

    Zhang, Jingyao; Song, Sidong; Pang, Qing; Zhang, Ruiyao; Zhou, Lei; Liu, Sushun; Meng, Fandi; Wu, Qifei; Liu, Chang

    2015-01-01

    Acetaminophen (APAP) overdose is a major cause of acute liver failure. Peripheral 5-hydroxytryptamine (serotonin, 5-HT) is a cytoprotective neurotransmitter which is also involved in the hepatic physiological and pathological process. This study seeks to investigate the mechanisms involved in APAP-induced hepatotoxicity, as well as the role of 5-HT in the liver's response to APAP toxicity. We induced APAP hepatotoxicity in mice either sufficient of serotonin (wild-type mice and TPH1-/- plus 5- Hydroxytryptophan (5-HTP)) or lacking peripheral serotonin (Tph1-/- and wild-type mice plus p-chlorophenylalanine (PCPA)).Mice with sufficient 5-HT exposed to acetaminophen have a significantly lower mortality rate and a better outcome compared with mice deficient of 5-HT. This difference is at least partially attributable to a decreased level of inflammation, oxidative stress and endoplasmic reticulum (ER) stress, Glutathione (GSH) depletion, peroxynitrite formation, hepatocyte apoptosis, elevated hepatocyte proliferation, activation of 5-HT2B receptor, less activated c-Jun NH2-terminal kinase (JNK) and hypoxia-inducible factor (HIF)-1α in the mice sufficient of 5-HT versus mice deficient of 5-HT. We thus propose a physiological function of serotonin that serotonin could ameliorate APAP-induced liver injury mainly through inhibiting hepatocyte apoptosis ER stress and promoting liver regeneration. PMID:25631548

  15. Serotonin deficiency exacerbates acetaminophen-induced liver toxicity in mice.

    PubMed

    Zhang, Jingyao; Song, Sidong; Pang, Qing; Zhang, Ruiyao; Zhou, Lei; Liu, Sushun; Meng, Fandi; Wu, Qifei; Liu, Chang

    2015-01-29

    Acetaminophen (APAP) overdose is a major cause of acute liver failure. Peripheral 5-hydroxytryptamine (serotonin, 5-HT) is a cytoprotective neurotransmitter which is also involved in the hepatic physiological and pathological process. This study seeks to investigate the mechanisms involved in APAP-induced hepatotoxicity, as well as the role of 5-HT in the liver's response to APAP toxicity. We induced APAP hepatotoxicity in mice either sufficient of serotonin (wild-type mice and TPH1-/- plus 5- Hydroxytryptophan (5-HTP)) or lacking peripheral serotonin (Tph1-/- and wild-type mice plus p-chlorophenylalanine (PCPA)). Mice with sufficient 5-HT exposed to acetaminophen have a significantly lower mortality rate and a better outcome compared with mice deficient of 5-HT. This difference is at least partially attributable to a decreased level of inflammation, oxidative stress and endoplasmic reticulum (ER) stress, Glutathione (GSH) depletion, peroxynitrite formation, hepatocyte apoptosis, elevated hepatocyte proliferation, activation of 5-HT2B receptor, less activated c-Jun NH₂-terminal kinase (JNK) and hypoxia-inducible factor (HIF)-1α in the mice sufficient of 5-HT versus mice deficient of 5-HT. We thus propose a physiological function of serotonin that serotonin could ameliorate APAP-induced liver injury mainly through inhibiting hepatocyte apoptosis ER stress and promoting liver regeneration.

  16. Reduced Atherosclerosis in apoE-inhibitory FcγRIIb-Deficient Mice Is Associated With Increased Anti-Inflammatory Responses by T Cells and Macrophages.

    PubMed

    Ng, Hang Pong; Zhu, Xinmei; Harmon, Erin Y; Lennartz, Michelle R; Nagarajan, Shanmugam

    2015-05-01

    Fcγ receptors (FcγRs) are classified as activating (FcγRI, III, and IV) and inhibitory (FcγRII) receptors. We have reported that deletion of activating FcγRs in apolipoprotein E (apoE) single knockout mice attenuated atherosclerosis. In this report, we investigated the hypothesis that deficiency of inhibitory FcγRIIb exacerbates atherosclerosis. ApoE-FcγRIIb double knockout mice, congenic to the C57BL/6 (apoE-FcγRIIbB6 (-/-)), were generated and atherosclerotic lesions were assessed. In contrary to our hypothesis, when compared with apoE single knockout mice, arterial lesions were significantly decreased in apoE-FcγRIIbB6 (-/-) male and female mice fed chow or high-fat diets. Chimeric mice generated by transplanting apoE-FcγRIIbB6 (-/-) marrow into apoE single knockout mice also developed reduced lesions. CD4(+) T cells from apoE-FcγRIIbB6 (-/-) mice produced higher levels of interleukin-10 and transforming growth factor-β than their apoE single knockout counterparts. As our findings conflict with a previous report using apoE-FcγRIIb129/B6 (-/-) mice on a mixed genetic background, we investigated whether strain differences contributed to the anti-inflammatory response. Macrophages from FcγRIIb129/B6 (-/-) mice on a mixed genetic background produced more interleukin-1β and MCP-1 (monocyte chemoattractant protein-1) in response to immune complexes, whereas congenic FcγRIIbB6 (-/-) mice generated more interleukin-10 and significantly less interleukin-1β. Interestingly, the expression of lupus-associated slam genes, located in proximity to fcgr2b in mouse chromosome 1, is upregulated only in mixed FcγRIIb129/B6 (-/-) mice. Our findings demonstrate a detrimental role for FcγRIIb signaling in atherosclerosis and the contribution of anti-inflammatory cytokine responses in the attenuated lesions observed in apoE-FcγRIIbB6 (-/-) mice. As 129/sv genome-derived lupus-associated genes have been implicated in lupus phenotype in FcγRIIb129/B6 (-/-) mice, our

  17. Dectin-1 deficiency does not affect atherosclerosis development in mice.

    PubMed

    Szilagyi, Katka; Gijbels, Marion J J; van der Velden, Saskia; Heinsbroek, Sigrid E M; Kraal, Georg; de Winther, Menno P J; van den Berg, Timo K

    2015-04-01

    Recent data suggest the involvement of dectin-1 in atherosclerosis through regulation of local reactive oxygen species production. The aim of the current study was to assess the effect of dectin-1 deficiency on atherosclerotic plaque development. Using immunohistochemistry dectin-1 expression was observed on foamy macrophages in atherosclerotic lesions in mice. Following lethal irradiation LDLR(-/-) mice were reconstituted with bone marrow from either wild type or dectin-1(-/-) mice. After recovery, mice were fed a high fat diet for 9 weeks and atherosclerotic lesions were analyzed. Overall, we found no significant differences in plaque size or severity between the groups. Also no differences were observed in granulocyte or macrophage composition of the plaques or in the ability to produce reactive oxygen species by macrophages from both groups. Dectin-1 is dispensable for the development of atherosclerotic lesions in mice. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  18. Induction of follistatin precedes gastric transformation in gastrin deficient mice

    SciTech Connect

    Kang Weiqun; Saqui-Salces, Milena; Zavros, Yana; Merchant, Juanita L.

    2008-11-21

    We previously showed that antral gastric tumors develop in gastrin-deficient (Gas{sup -/-}) mice. Therefore Gas{sup -/-}mice were studied sequentially over 12 months to identify molecular mechanisms underlying gastric transformation. Fundic atrophy developed by 9 months in Gas{sup -/-} mice. Antral mucosal hyperplasia developed coincident with the focal loss of TFF1 and Muc5AC. Microarray analysis of 12 month Gas{sup -/-} tumors revealed an increase in follistatin, an activin/BMP antagonist. We found that elevated follistatin expression occurred in the proliferative neck zone of hyperplastic antrums, in antral tumors of Gas{sup -/-} mice, and also in human gastric cancers. Follistatin induced cyclin D1 and the trefoil factors TFF1 and TFF2 in a gastric cancer cell line. We concluded that antral hyperplasia in Gas{sup -/-} mice involves amplification of mucous cell lineages due to follistatin, suggesting its role in the development of antral gastric tumors.

  19. Postural and locomotor control in normal and vestibularly deficient mice

    PubMed Central

    Vidal, P-P; Degallaix, L; Josset, P; Gasc, J-P; Cullen, K E

    2004-01-01

    We investigated how vestibular information is used to maintain posture and control movement by studying vestibularly deficient mice (IsK−/− mutant). In these mutants, microscopy showed degeneration of the cristae of the semicircular canals and of the maculae of the utriculi and sacculi, while behavioural and vestibulo-ocular reflex testing showed that vestibular function was completely absent. However, the histology of Scarpa's ganglia and the vestibular nerves was normal in mutant mice, indicating the presence of intact central pathways. Using X-ray and high-speed cineradiography, we compared resting postures and locomotion patterns between these vestibularly deficient mice and vestibularly normal mice (wild-type and IsK+/−). The absence of vestibular function did not affect resting posture but had profound effects on locomotion. At rest, the S-shaped, sagittal posture of the vertebral column was the same for wild-type and mutant mice. Both held the head with the atlanto-occipital joint fully flexed, the cervico-thoracic junction fully flexed, and the cervical column upright. Wild-type mice extended the head and vertebral column and could walk in a straight line. In marked contrast, locomotion in vestibularly deficient mice was characterized by circling episodes, during which the vertebral column maintained an S-shaped posture. Thus, vestibular information is not required to control resting posture but is mandatory for normal locomotion. We propose that vestibular inputs are required to signal the completion of a planned trajectory because mutant mice continued rotating after changing heading direction. Our findings support the hypothesis that vertebrates limit the number of degrees of freedom to be controlled by adopting just a few of the possible skeletal configurations. PMID:15243133

  20. Bone matrix hypermineralization in prolyl-3 hydroxylase 1 deficient mice.

    PubMed

    Fratzl-Zelman, Nadja; Bächinger, Hans-Peter; Vranka, Janice A; Roschger, Paul; Klaushofer, Klaus; Rauch, Frank

    2016-04-01

    Lack of prolyl 3-hydroxylase 1 (P3H1) due to mutations in P3H1 results in severe forms of recessive osteogenesis imperfecta. In the present study, we investigated the bone tissue characteristics of P3H1 null mice. Histomorphometric analyses of cancellous bone in the proximal tibia and lumbar vertebra in 1-month and 3-month old mice demonstrated that P3H1 deficient mice had low trabecular bone volume and low mineral apposition rate, but normal osteoid maturation time and normal osteoblast and osteoclast surfaces. Quantitative backscattered electron imaging revealed that the bone mineralization density distribution was shifted towards higher values, indicating hypermineralization of bone matrix. It thus appears that P3H1 deficiency leads to decreased deposition of extracellular matrix by osteoblasts and increased incorporation of mineral into the matrix. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Apolipoprotein E genotyping and cerebrospinal fluid tau protein: implications for the clinical diagnosis of Alzheimer's disease.

    PubMed

    Arai, H; Higuchi, S; Sasaki, H

    1997-01-01

    Apolipoprotein E (ApoE) genotyping was conducted in sporadic Alzheimer's disease (AD, n = 91) as well as in other dementing disorders including Parkinson's disease (PD, n = 73), autopsy-confirmed diffuse Lewy body disease (DLBD, n = 16), progressive supranuclear palsy (n = 13), vascular dementia (n = 55), alcoholic dementia (n =25) and normal control subjects (n = 77). ApoE epsilon 4 allele frequency was significantly higher in AD (33.5%, p < 0.001), DLBD (40.6%, p < 0.001) and demented PD (29.4%, p < 0.05) compared to that in normal controls (11.7%). The association of the ApoE epsilon 4 allele with AD was more pronounced in early-onset AD (46.4%) than in late-onset AD (27.8%). 46% of the AD individuals developed AD without association to ApoE epsilon 4, and epsilon 4 homozygotes were found not only in AD, but also in many of other dementing disorders. These results suggest that ApoE genotyping cannot provide certainty about the presence of absence of AD, and that it should be used as an adjunct to other diagnostic tests for AD. On the other hand, cerebrospinal fluid (CSF) tau levels were significantly elevated (p < 0.0001) in AD (78.0 +/- 44.2 pg/ml) compared to those in normal controls (10.6 +/- 8.6 pg/ml). The specificity and the sensitivity of distinguishing AD from normal controls was 95.0 and 91.2%, respectively. Elevated CSF-tau levels were also detected in some patients with acute neurological diseases including meningoencephalitis, Creutzfeld-Jacob disease, normal pressure hydrocephalus and vitamin B12 deficiency encephalopathy. Increased CSF-tau levels in AD were found regardless of the age at onset, clinical stage, ApoE genotype, alpha 1-antichymotrypsin genotype, and presenilin-1 genotype. The CSF-tau levels continued to be abnormal during the progression of AD. These results suggest that CSF-tau serves as an unequivocal and reliable biological marker to aid in the clinical diagnosis of AD.

  2. Comprehensive Behavioral Analysis of Activating Transcription Factor 5-Deficient Mice.

    PubMed

    Umemura, Mariko; Ogura, Tae; Matsuzaki, Ayako; Nakano, Haruo; Takao, Keizo; Miyakawa, Tsuyoshi; Takahashi, Yuji

    2017-01-01

    Activating transcription factor 5 (ATF5) is a member of the CREB/ATF family of basic leucine zipper transcription factors. We previously reported that ATF5-deficient (ATF5(-/-)) mice demonstrated abnormal olfactory bulb development due to impaired interneuron supply. Furthermore, ATF5(-/-) mice were less aggressive than ATF5(+/+) mice. Although ATF5 is widely expressed in the brain, and involved in the regulation of proliferation and development of neurons, the physiological role of ATF5 in the higher brain remains unknown. Our objective was to investigate the physiological role of ATF5 in the higher brain. We performed a comprehensive behavioral analysis using ATF5(-/-) mice and wild type littermates. ATF5(-/-) mice exhibited abnormal locomotor activity in the open field test. They also exhibited abnormal anxiety-like behavior in the light/dark transition test and open field test. Furthermore, ATF5(-/-) mice displayed reduced social interaction in the Crawley's social interaction test and increased pain sensitivity in the hot plate test compared with wild type. Finally, behavioral flexibility was reduced in the T-maze test in ATF5(-/-) mice compared with wild type. In addition, we demonstrated that ATF5(-/-) mice display disturbances of monoamine neurotransmitter levels in several brain regions. These results indicate that ATF5 deficiency elicits abnormal behaviors and the disturbance of monoamine neurotransmitter levels in the brain. The behavioral abnormalities of ATF5(-/-) mice may be due to the disturbance of monoamine levels. Taken together, these findings suggest that ATF5(-/-) mice may be a unique animal model of some psychiatric disorders.

  3. Comprehensive Behavioral Analysis of Activating Transcription Factor 5-Deficient Mice

    PubMed Central

    Umemura, Mariko; Ogura, Tae; Matsuzaki, Ayako; Nakano, Haruo; Takao, Keizo; Miyakawa, Tsuyoshi; Takahashi, Yuji

    2017-01-01

    Activating transcription factor 5 (ATF5) is a member of the CREB/ATF family of basic leucine zipper transcription factors. We previously reported that ATF5-deficient (ATF5-/-) mice demonstrated abnormal olfactory bulb development due to impaired interneuron supply. Furthermore, ATF5-/- mice were less aggressive than ATF5+/+ mice. Although ATF5 is widely expressed in the brain, and involved in the regulation of proliferation and development of neurons, the physiological role of ATF5 in the higher brain remains unknown. Our objective was to investigate the physiological role of ATF5 in the higher brain. We performed a comprehensive behavioral analysis using ATF5-/- mice and wild type littermates. ATF5-/- mice exhibited abnormal locomotor activity in the open field test. They also exhibited abnormal anxiety-like behavior in the light/dark transition test and open field test. Furthermore, ATF5-/- mice displayed reduced social interaction in the Crawley’s social interaction test and increased pain sensitivity in the hot plate test compared with wild type. Finally, behavioral flexibility was reduced in the T-maze test in ATF5-/- mice compared with wild type. In addition, we demonstrated that ATF5-/- mice display disturbances of monoamine neurotransmitter levels in several brain regions. These results indicate that ATF5 deficiency elicits abnormal behaviors and the disturbance of monoamine neurotransmitter levels in the brain. The behavioral abnormalities of ATF5-/- mice may be due to the disturbance of monoamine levels. Taken together, these findings suggest that ATF5-/- mice may be a unique animal model of some psychiatric disorders. PMID:28744205

  4. Does estrogen deficiency cause lacrimal gland inflammation and aqueous-deficient dry eye in mice?

    PubMed

    Rahimi Darabad, Raheleh; Suzuki, Tomo; Richards, Stephen M; Jakobiec, Frederick A; Zakka, Fouad R; Barabino, Stefano; Sullivan, David A

    2014-10-01

    Researchers have proposed that estrogen deficiency will lead to a Sjögren's syndrome (SjS)-like lacrimal gland inflammation, aqueous tear deficiency and dry eye. The purpose of this study was to determine whether this proposal is correct. Lacrimal glands were obtained from adult, age-matched wild type (WT) and aromatase knockout (ArKO) mice, in which estrogen synthesis is completely eliminated. Tissues were also obtained from autoimmune MRL/Mp-lpr/lpr (MRL/lpr) mice as inflammation controls. Tear volumes in WT and ArKO mice were measured and glands were processed for molecular biological and histological evaluation. Our results demonstrate that estrogen absence does not lead to a SjS-like inflammation in lacrimal tissue or to an aqueous-deficient dry eye. There was no upregulation of genes associated with inflammatory pathways in lacrimal glands of male or female ArKO mice. Such inflammatory activity was prominent in autoimmune MRL/lpr tissues. We also found no evidence of inflammation in lacrimal gland tissue sections of estrogen-deficient mice, and tear volumes of ArKO males were actually increased as compared to those WT controls. Interestingly, our study did show that estrogen absence influences the expression of thousands of lacrimal gland genes, and that this impact is sex- and genotype-specific. Our findings demonstrate that estrogen absence is not a risk factor for the development of SjS-like lacrimal gland inflammation or for aqueous-deficient dry eye in mice. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Does estrogen deficiency cause lacrimal gland inflammation and aqueous-deficient dry eye in mice?

    PubMed Central

    Darabad, Raheleh Rahimi; Suzuki, Tomo; Richards, Stephen M.; Jakobiec, Frederick A.; Zakka, Fouad R.; Barabino, Stefano; Sullivan, David A.

    2014-01-01

    Researchers have proposed that estrogen deficiency will lead to a Sjögren's syndrome (SjS)-like lacrimal gland inflammation, aqueous tear deficiency and dry eye. The purpose of this study was to determine whether this proposal is correct. Lacrimal glands were obtained from adult, age-matched wild type (WT) and aromatase knockout (ArKO) mice, in which estrogen synthesis is completely eliminated. Tissues were also obtained from autoimmune MRL/Mp-lpr/lpr (MRL/lpr) mice as inflammation controls. Tear volumes in WT and ArKO mice were measured and glands were processed for molecular biological and histological evaluation. Our results demonstrate that estrogen absence does not lead to a SjS-like inflammation in lacrimal tissue or to an aqueous-deficient dry eye. There was no upregulation of genes associated with inflammatory pathways in lacrimal glands of male or female ArKO mice. Such inflammatory activity was prominent in autoimmune MRL/lpr tissues. We also found no evidence of inflammation in lacrimal gland tissue sections of estrogen-deficient mice, and tear volumes of ArKO males were actually increased as compared to those WT controls. Interestingly, our study did show that estrogen absence influences the expression of thousands of lacrimal gland genes, and that this impact is sex- and genotype-specific. Our findings demonstrate that estrogen absence is not a risk factor for the development of SjS-like lacrimal gland inflammation or for aqueous-deficient dry eye in mice. PMID:25084452

  6. Liver X receptor agonist treatment significantly affects phenotype and transcriptome of APOE3 and APOE4 Abca1 haplo-deficient mice

    PubMed Central

    Fitz, Nicholas F.; Mounier, Anais; Wolfe, Cody M.; Nam, Kyong Nyon; Reeves, Valerie L.; Kamboh, Hafsa; Koldamova, Radosveta

    2017-01-01

    ATP-binding cassette transporter A1 (ABCA1) controls cholesterol and phospholipid efflux to lipid-poor apolipoprotein E (APOE) and is transcriptionally controlled by Liver X receptors (LXRs) and Retinoic X Receptors (RXRs). In APP transgenic mice, lack of Abca1 increased Aβ deposition and cognitive deficits. Abca1 haplo-deficiency in mice expressing human APOE isoforms, increased level of Aβ oligomers and worsened memory deficits, preferentially in APOE4 mice. In contrast upregulation of Abca1 by LXR/RXR agonists significantly ameliorated pathological phenotype of those mice. The goal of this study was to examine the effect of LXR agonist T0901317 (T0) on the phenotype and brain transcriptome of APP/E3 and APP/E4 Abca1 haplo-deficient (APP/E3/Abca1+/- and APP/E4/Abca1+/-) mice. Our data demonstrate that activated LXRs/RXR ameliorated APOE4-driven pathological phenotype and significantly affected brain transcriptome. We show that in mice expressing either APOE isoform, T0 treatment increased mRNA level of genes known to affect brain APOE lipidation such as Abca1 and Abcg1. In both APP/E3/Abca1+/- and APP/E4/Abca1+/- mice, the application of LXR agonist significantly increased ABCA1 protein level accompanied by an increased APOE lipidation, and was associated with restoration of APOE4 cognitive deficits, reduced levels of Aβ oligomers, but unchanged amyloid load. Finally, using Gene set enrichment analysis we show a significant APOE isoform specific response to LXR agonist treatment: Gene Ontology categories “Microtubule Based Process” and “Synapse Organization” were differentially affected in T0-treated APP/E4/Abca1+/- mice. Altogether, the results are suggesting that treatment of APP/E4/Abca1+/- mice with LXR agonist T0 ameliorates APOE4-induced AD-like pathology and therefore targeting the LXR-ABCA1-APOE regulatory axis could be effective as a potential therapeutic approach in AD patients, carriers of APOEε4. PMID:28241068

  7. AMPD3-deficient mice exhibit increased erythrocyte ATP levels but anemia not improved due to PK deficiency.

    PubMed

    Cheng, Jidong; Morisaki, Hiroko; Toyama, Keiko; Ikawa, Masahito; Okabe, Masaru; Morisaki, Takayuki

    2012-11-01

    AMP deaminase (AMPD) catalyzes AMP to IMP and plays an important role in energy charge and nucleotide metabolism. Human AMPD3 deficiency is a type of erythrocyte-specific enzyme deficiency found in individuals without clinical symptoms, although an increased level of ATP in erythrocytes has been reported. To better understand the physiological and pathological roles of AMPD3 deficiency, we established a line of AMPD3-deficient [A3(-/-)] mice. No AMPD activity and a high level of ATP were observed in erythrocytes of these mice, similar to human RBC-AMPD3 deficiency, while other characteristics were unremarkable. Next, we created AMPD3 and pyruvate kinase (PK) double-deficient [PKA(-/-,-/-)] mice by mating A3(-/-) mice with CBA-Pk-1slc/Pk-1slc mice [PK(-/-)], a spontaneous PK-deficient strain showing hemolytic anemia. In PKA(-/-,-/-) mice, the level of ATP in red blood cells was increased 1.5 times as compared to PK(-/-) mice, although hemolytic anemia in those animals was not improved. In addition, we observed osmotic fragility of erythrocytes in A3(-/-) mice under fasting conditions. In contrast, the ATP level in erythrocytes was elevated in A3(-/-) mice as compared to the control. In conclusion, AMPD3 deficiency increases the level of ATP in erythrocytes, but does not improve anemia due to PK deficiency and leads to erythrocyte dysfunction.

  8. Inflammation imaging of atherosclerosis in Apo-E-deficient mice using a (99m)Tc-labeled dual-domain cytokine ligand.

    PubMed

    Liu, Zhonglin; Lerman, Lilach O; Tang, Hui; Barber, Christy; Wan, Li; Hui, Mizhou M; Furenlid, Lars R; Woolfenden, James M

    2014-01-01

    Interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) play a critical role in initiating and accelerating atherosclerosis. This study evaluated the imaging properties of (99m)Tc-TNFR2-Fc-IL-1RA ((99m)Tc-TFI), a dual-domain cytokine radioligand that targets TNF-α and IL-1β pathways, in assessing atherosclerosis development in apolipoprotein-E-deficient (ApoE(-)(/)(-)) mice. The feasibility and specificity of detecting atherosclerosis with (99m)Tc-TFI SPECT imaging were investigated in ApoE(-)(/)(-) and ApoE(+)(/)(+) mice. Fifty-four ApoE(-)(/)(-) mice were fed either an atherogenic diet (AGD) or a normal diet (ND) beginning at 5 weeks of age. Eighteen Apo-E wild-type (ApoE(+)(/)(+)) mice were fed an ND. Two groups of ApoE(-)(/)(-) mice (n=12 each group) on AGD and ND were imaged three times with (99m)Tc-TFI and a high-resolution SPECT system at 20-25, 30-40, and 48-52 weeks to study the evolution of atherosclerotic plaque. Focal radioactive accumulations in the aortic arch region were observed in the ApoE(-)(/)(-) mice (n=12) on AGD but not in the ApoE(+)(/)(+) mice on ND (n=10). Apo-E(-)(/)(-) mice on ND (n=11) exhibited lower radioactive uptake than ApoE(-)(/)(-) mice on AGD (P<0.05). Co-injection of an excess of cold ligand with (99m)Tc-TFI resulted in significant reduction of (99m)Tc-TFI uptake in the ApoE(-)(/)(-) mice on AGD. Longitudinal studies showed that (99m)Tc-TFI uptake in the aortas of ApoE(-)(/)(-) mice progressively increased from 20 to 48 weeks. Real-time PCR assays demonstrated that atherosclerotic aortas expressed significantly higher IL-1β and TNF-α than the aortas from wild-type controls. Atherosclerotic plaques were detected by (99m)Tc-TFI imaging in ApoE(-)(/)(-) mice. (99m)Tc-TFI is promising for specific detection of inflammatory response in atherosclerotic plaques. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. OxLDL-targeted iron oxide nanoparticles for in vivo MRI detection of perivascular carotid collar induced atherosclerotic lesions in ApoE-deficient mice

    PubMed Central

    Wen, Song; Liu, Dong-Fang; Liu, Zhen; Harris, Steven; Yao, Yu-Yu; Ding, Qi; Nie, Fang; Lu, Tong; Chen, Hua-Jun; An, Yan-Li; Zang, Feng-Chao; Teng, Gao-Jun

    2012-01-01

    Atherosclerotic disease is a leading cause of morbidity and mortality in developed countries, and oxidized LDL (OxLDL) plays a key role in the formation, rupture, and subsequent thrombus formation in atherosclerotic plaques. In the current study, anti-mouse OxLDL polyclonal antibody and nonspecific IgG antibody were conjugated to polyethylene glycol-coated ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles, and a carotid perivascular collar model in apolipoprotein E-deficient mice was imaged at 7.0 Tesla MRI before contrast administration and at 8 h and 24 h after injection of 30 mg Fe/kg. The results showed MRI signal loss in the carotid atherosclerotic lesions after administration of targeted anti-OxLDL-USPIO at 8 h and 24 h, which is consistent with the presence of the nanoparticles in the lesions. Immunohistochemistry confirmed the colocalization of the OxLDL/macrophages and iron oxide nanoparticles. The nonspecific IgG-USPIO, unconjugated USPIO nanoparticles, and competitive inhibition groups had limited signal changes (p < 0.05). This report shows that anti-OxLDL-USPIO nanoparticles can be used to directly detect OxLDL and image atherosclerotic lesions within 24 h of nanoparticle administration and suggests a strategy for the therapeutic evaluation of atherosclerotic plaques in vivo. PMID:22393161

  10. Maladaptive defensive behaviours in monoamine oxidase A-deficient mice

    PubMed Central

    Godar, Sean C.; Bortolato, Marco; Frau, Roberto; Dousti, Mona; Chen, Kevin; Shih, Jean C.

    2012-01-01

    Rich evidence indicates that monoamine oxidase (MAO) A, the major enzyme catalysing the degradation of monoamine neurotransmitters, plays a key role in emotional regulation. Although MAOA deficiency is associated with reactive aggression in humans and mice, the involvement of this enzyme in defensive behaviour remains controversial and poorly understood. To address this issue, we tested MAOA knockout (KO) mice in a spectrum of paradigms and settings associated with variable degrees of threat. The presentation of novel inanimate objects induced a significant reduction in exploratory approaches and increase in defensive behaviours, such as tail-rattling, biting and digging. These neophobic responses were context-dependent and particularly marked in the home cage. In the elevated plus- and T-mazes, MAOA KO mice and wild-type (WT) littermates displayed equivalent locomotor activity and time in closed and open arms; however, MAOA KO mice featured significant reductions in risk assessment, as well as unconditioned avoidance and escape. No differences between genotypes were observed in the defensive withdrawal and emergence test. Conversely, MAOA KO mice exhibited a dramatic reduction of defensive and fear-related behaviours in the presence of predator-related cues, such as predator urine or an anaesthetized rat, in comparison with those observed in their WT littermates. The behavioural abnormalities in MAOA KO mice were not paralleled by overt alterations in sensory and microvibrissal functions. Collectively, these results suggest that MAOA deficiency leads to a general inability to appropriately assess contextual risk and attune defensive and emotional responses to environmental cues. PMID:21156093

  11. Vitamin A Deficiency Impairs Induction of Oral Tolerance in Mice.

    PubMed

    Nakamoto, Akiko; Shuto, Emi; Tsutsumi, Rie; Nakamoto, Mariko; Nii, Yoshitaka; Sakai, Tohru

    2015-01-01

    Oral tolerance is a phenomenon of induction of systemic unresponsiveness to antigens ingested by the oral route and loss of immune response. Studies have shown the importance of vitamin A in oral tolerance in vitro but not in an in vivo experimental model. Therefore, we carried out experiments to determine how vitamin A deficiency affects tolerance induction and the ability of mesenteric lymph node (MLN) CD11c(+) cells to induce regulatory T cells (Tregs). Immunological tolerance was induced by oral ovalbumin (OVA) administration in vitamin A-sufficient mice. OVA-specific antibody and cytokine production were significantly reduced. On the other hand, in vitamin A-deficient mice, both OVA-specific antibody and cytokine production were not suppressed by oral OVA administration. Regarding induction of Tregs, the conversion rate of Foxp3(+) cells from naïve CD4(+) cell by CD11c(+) cells was decreased in vitamin A-deficient mice. Our study indicates that vitamin A deficiency causes the breakdown of oral tolerance in vivo.

  12. SAP deficiency mitigated atherosclerotic lesions in ApoE(-/-) mice.

    PubMed

    Zheng, Lingyun; Wu, Teng; Zeng, Cuiling; Li, Xiangli; Li, Xiaoqiang; Wen, Dingwen; Ji, Tianxing; Lan, Tian; Xing, Liying; Li, Jiangchao; He, Xiaodong; Wang, Lijing

    2016-01-01

    Serum amyloid P conpoent (SAP), a member of the pentraxin family, interact with pathogens and cell debris to promote their removal by macrophages and neutrophils and is co-localized with atherosclerotic plaques in patients. However, the exact mechanism of SAP in atherogenesis is still unclear. We investigated whether SAP influence macrophage recruitment and foam cell formation and ultimately affect atherosclerotic progression. we generated apoE(-/-); SAP(-/-) (DKO) mice and fed them western diet for 4 and 8 weeks to characterize atherosclerosis development. SAP deficiency effectively reduced plaque size both in the aorta (p = 0.0006 for 4 wks; p = 0.0001 for 8 wks) and the aortic root (p = 0.0061 for 4 wks; p = 0.0079 for 8wks) compared with apoE(-/-) mice. Meanwhile, SAP deficiency inhibited oxLDL-induced foam cell formation (p = 0.0004) compared with apoE(-/-) mice and SAP treatment increases oxLDL-induced foam cell formation (p = 0.002) in RAW cells. Besides, SAP deficiency reduced macrophages recruitment (p = 0.035) in vivo and in vitro (p = 0.026). Furthermore, SAP treatment enhanced CD36 (p = 0.007) and FcγRI (p = 0.031) expression induced by oxLDL through upregulating JNK and p38 MAPK phosphorylation whereas specific JNK1/2 inhibitor reduced CD36 (p = 0.0005) and FcγRI (P = 0.0007) expression in RAW cell. SAP deficiency also significantly decreased the expression of M1 and M2 macrophage markers and inflammatory cytokines in oxLDL-induced macrophages. SAP deficiency mitigated foam cell formation and atherosclerotic development in apoE(-/-) mice, due to reduction in macrophages recruitment, polarization and pro-inflammatory cytokines and inhibition the CD36/FcγR-dependent signaling pathway. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  13. Developmental window of sensorineural deafness in biotinidase-deficient mice.

    PubMed

    Maheras, Kathleen June; Pindolia, Kirit; Wolf, Barry; Gow, Alexander

    2017-05-17

    Biotinidase deficiency is an autosomal recessively inherited disorder that results in the inability to recycle the vitamin, biotin. If untreated, the disorder can result in a range of neurological and cutaneous symptoms, including sensorineural deficits and deafness. To understand early mechanistic abnormalities that may precede more generalized and nonspecific effects of metabolic deficits such as weight loss and acidosis, we have analyzed auditory brainstem responses (ABRs) in biotinidase-deficient knockout (Btd (-/-) ) mice in the periweaning period with or without dietary biotin supplementation. We find significant increases in the latency of wave V of the ABR elicited by pure tone stimuli at one octave intervals, which precede substantial increases in ABR thresholds. Finer interpeak latency analyses of these changes indicate they are confined to the latter ABR waves associated with the CNS and likely reflect slowed brainstem transmission time. In contrast, peripheral nervous system conduction velocity appears normal. Further, we find that biotin-supplementation after the onset of symptoms reverses the latency shifts, which has significant relevance for early treatment in patients. Finally, ABR latencies in Btd (-/-) mice fed a biotin-supplemented diet for the first month of life appear refractory to transmission time slowing during a subsequent bout of biotin deficiency. These data suggest a transient vulnerability window for biotin deficiency in the auditory brainstem. Finally, we also observe a developmental vulnerability window involving follicular melanosome production or melanocyte survival. Sensorineural deafness precedes peripheral hearing loss in developmental biotinidase deficiency and is transient if rescued by dietary biotin within a short developmental window.

  14. Distinct Hepatic Receptors for Low Density Lipoprotein and Apolipoprotein E in Humans

    NASA Astrophysics Data System (ADS)

    Hoeg, Jeffrey M.; Demosky, Stephen J.; Gregg, Richard E.; Schaefer, Ernst J.; Brewer, H. Bryan

    1985-02-01

    Since the liver is a central organ for lipid and lipoprotein synthesis and catabolism, hepatic receptors for specific apolipoproteins on plasma lipoproteins would be expected to modulate lipid and lipoprotein metabolism. The role of hepatic receptors for low density lipoproteins and apolipoprotein E-containing lipoproteins was evaluated in patients with complementary disorders in lipoprotein metabolism: abetalipoproteinemia and homozygous familial hypercholesterolemia. In addition, hepatic membranes from a patient with familial hypercholesterolemia were studied and compared before and after portacaval shunt surgery. The results establish that the human liver has receptors for apolipoproteins B and E. Furthermore, in the human, hepatic receptors for low density lipoproteins and apolipoprotein E are genetically distinct and can undergo independent control.

  15. Anemia and splenomegaly in cGKI-deficient mice

    PubMed Central

    Föller, Michael; Feil, Susanne; Ghoreschi, Kamran; Koka, Saisudha; Gerling, Andrea; Thunemann, Martin; Hofmann, Franz; Schuler, Beat; Vogel, Johannes; Pichler, Bernd; Kasinathan, Ravi S.; Nicolay, Jan P.; Huber, Stephan M.; Lang, Florian; Feil, Robert

    2008-01-01

    To explore the functional significance of cGMP-dependent protein kinase type I (cGKI) in the regulation of erythrocyte survival, gene-targeted mice lacking cGKI were compared with their control littermates. By the age of 10 weeks, cGKI-deficient mice exhibited pronounced anemia and splenomegaly. Compared with control mice, the cGKI mutants had significantly lower red blood cell count, packed cell volume, and hemoglobin concentration. Anemia was associated with a higher reticulocyte number and an increase of plasma erythropoietin concentration. The spleens of cGKI mutant mice were massively enlarged and contained a higher fraction of Ter119+ erythroid cells, whereas the relative proportion of leukocyte subpopulations was not changed. The Ter119+ cGKI-deficient splenocytes showed a marked increase in annexin V binding, pointing to phosphatidylserine (PS) exposure at the outer membrane leaflet, a hallmark of suicidal erythrocyte death or eryptosis. Compared with control erythrocytes, cGKI-deficient erythrocytes exhibited in vitro a higher cytosolic Ca2+ concentration, a known trigger of eryptosis, and showed increased PS exposure, which was paralleled by a faster clearance in vivo. Together, these results identify a role of cGKI as mediator of erythrocyte survival and extend the emerging concept that cGMP/cGKI signaling has an antiapoptotic/prosurvival function in a number of cell types in vivo. PMID:18443297

  16. Behavioral analysis of narcoleptic episodes in orexin-deficient mice.

    PubMed

    Leibiger, Judith; Fendt, Markus

    2014-03-01

    Orexin-deficient mice express narcoleptic episodes which mirror some of the main symptoms of human narcolepsy. Therefore, they are often used in narcolepsy research. However, little is known about some behavioral characteristics of narcoleptic episodes, e.g. about episode types, duration, and variability. In the present study, 351 narcoleptic episodes of orexin-deficient mice were behaviorally characterized. Based on this data, we describe different onset and progression episodes types. These episode types affected episode duration, i.e. abrupt onsets and 'shaking'-like movements increased episode duration. Our data suggests that promoting motor activity enhances the frequency of narcoleptic episode. Inter-individual variability of episode frequency and duration was large; however, the intra-individual frequency was relatively stable. Based on these findings we suggest the following to increase the statistical power of experiments in orexin-deficient mice: Using a pre-screen and selecting the mice with decent episode frequency, using an enriched environment as well as using repeated-measure designs.

  17. Osteopontin Deficiency Suppresses Intestinal Tumor Development in Apc-Deficient Min Mice.

    PubMed

    Ishigamori, Rikako; Komiya, Masami; Takasu, Shinji; Mutoh, Michihiro; Imai, Toshio; Takahashi, Mami

    2017-05-14

    Osteopontin (OPN) is a secreted phosphoglycoprotein, and is a transcriptional target of aberrant Wnt signaling. OPN is upregulated in human colon cancers, and is suggested to enhance cancer progression. In this study, the effect of deficiency of OPN on intestinal tumor development in Apc-deficient Min mice was investigated. At 16 weeks of age, the number of small intestinal polyps in Min/OPN(+/-) and Min/OPN(-/-) mice was lower than that of Min/OPN(+/+) mice. Colorectal tumor incidences and multiplicities in Min/OPN(+/-) and Min/OPN(-/-) mice were significantly lower than those in Min/OPN(+/+) mice, being 48% and 0.6 ± 0.8, 50% and 0.8 ± 0.9 vs. 80% and 1.6 ± 1.7, respectively. OPN expression in colorectal tumors was strongly upregulated in Min/OPN(+/+) compared to adjacent non-tumor parts, but was decreased in Min/OPN(+/-) and not detected in Min/OPN(-/-). Targets of OPN, matrix metalloproteinases (MMPs)-3, -9, and -13 were lowered by OPN deficiency. Macrophage marker F4/80 in colorectal tumors was also lowered by OPN deficiency. MMP-9 expression was observed in tumor cells and tumor-infiltrating neutrophils. These results indicate that induction of OPN by aberrant Wnt signaling could enhance colorectal tumor development in part by upregulation of MMP-3, -9, and -13 and infiltration of macrophage and neutrophils. Suppression of OPN expression could contribute to tumor prevention, but complete deficiency of OPN may cause some adverse effects.

  18. Photic Resetting and Entrainment in CLOCK-Deficient Mice

    PubMed Central

    Dallmann, Robert; DeBruyne, Jason P.; Weaver, David R.

    2012-01-01

    Mice lacking CLOCK protein have a relatively subtle circadian phenotype, including a slightly shorter period in constant darkness, differences in phase resetting after 4-hr light pulses in the early and late night, and a variably advanced phase angle of entrainment in a light-dark (LD) cycle (DeBruyne et al., Neuron 50:465–477, 2006). The present series of experiments was conducted to more fully characterize the circadian phenotype of Clock−/− mice under various lighting conditions. A phase-response curve (PRC) to 4-hour light pulses in free-running mice was conducted; the results confirm that Clock−/− mice exhibit very large phase advances after 4 hrs light pulses in the late subjective night, but have relatively normal responses to light at other phases. The abnormal shape of the PRC to light may explain the tendency of CLOCK-deficient mice to begin activity before lights-out when housed in a 12 hrs light: 12 hrs dark lighting schedule. To assess this relationship further, Clock−/− and wild-type control mice were entrained to skeleton lighting cycles (1L:23D, and 1L:10D:1L:12D). Comparing entrainment under the two types of skeleton photoperiods revealed that exposure to 1 hr light in the morning leads to a phase advance of activity onset (expressed the following afternoon) in Clock−/− mice, but not in the controls. Constant light typically causes an intensity-dependent increase in circadian period in mice, but this did not occur in CLOCK-deficient mice. The failure of Clock−/− mice to respond to the period-lengthening effect of constant light likely results from the increased functional impact of light falling in the phase advance zone of the PRC. Collectively, these experiments reveal that alterations in the response of CLOCK-deficient mice to light in several paradigms are likely due to an imbalance in the shape of the PRC to light. PMID:21921293

  19. Association of apolipoprotein E allele {epsilon}4 with late-onset sporadic Alzheimer`s disease

    SciTech Connect

    Lucotte, G.; David, F.; Berriche, S.

    1994-09-15

    Apolipoprotein E, type {epsilon}4 allele (ApoE {epsilon}4), is associated with late-onset sporadic Alzheimer`s disease (AD) in French patients. The association is highly significant (0.45 AD versus 0.12 controls for {epsilon}4 allele frequencies). These data support the involvement of ApoE {epsilon}4 allele as a very important risk factor for the clinical expression of AD. 22 refs., 1 fig., 3 tabs.

  20. Dopamine D(3) receptor deficiency sensitizes mice to iron deficiency-related deficits in motor learning.

    PubMed

    Klinker, F; Hasan, K; Dowling, P; Paulus, W; Liebetanz, D

    2011-07-07

    Iron deficiency is a widespread form of malnutrition and is known to interfere with cognitive performance and development. To elucidate the role of dopamine D3 and iron deficiency (ID) in inducing cognitive deficits, we studied wildtype and D3 knockout mice on normal or iron-deficient diets subjected to a running wheel-based motor skill sequence. Surprisingly, ID alone had no effect on motor learning in this study, whereas combined ID and dopamine D(3) receptor (D3R)-deficiency significantly interfered with the acquisition of motor skills. Reduced D3R function may serve as a predisposing factor towards ID-related effects on motor learning. Copyright © 2011 Elsevier B.V. All rights reserved.

  1. Aged PROP1 Deficient Dwarf Mice Maintain ACTH Production

    PubMed Central

    Bavers, David L.; Beuschlein, Felix; Mortensen, Amanda H.; Keegan, Catherine E.; Hammer, Gary D.; Camper, Sally A.

    2011-01-01

    Humans with PROP1 mutations have multiple pituitary hormone deficiencies (MPHD) that typically advance from growth insufficiency diagnosed in infancy to include more severe growth hormone (GH) deficiency and progressive reduction in other anterior pituitary hormones, eventually including adrenocorticotropic hormone (ACTH) deficiency and hypocortisolism. Congenital deficiencies of GH, prolactin, and thyroid stimulating hormone have been reported in the Prop1null (Prop1-/-) and the Ames dwarf (Prop1df/df) mouse models, but corticotroph and pituitary adrenal axis function have not been thoroughly investigated. Here we report that the C57BL6 background sensitizes mutants to a wasting phenotype that causes approximately one third to die precipitously between weaning and adulthood, while remaining homozygotes live with no signs of illness. The wasting phenotype is associated with severe hypoglycemia. Circulating ACTH and corticosterone levels are elevated in juvenile and aged Prop1 mutants, indicating activation of the pituitary-adrenal axis. Despite this, young adult Prop1 deficient mice are capable of responding to restraint stress with further elevation of ACTH and corticosterone. Low blood glucose, an expected side effect of GH deficiency, is likely responsible for the elevated corticosterone level. These studies suggest that the mouse model differs from the human patients who display progressive hormone loss and hypocortisolism. PMID:22145038

  2. Dietary protein deficiency in pregnant mice and offspring.

    PubMed

    Millis, Richard M; Offiah, Godwin U

    2007-03-06

    Previous studies suggest an association between dermal contact hypersensitivity and preterm delivery. We hypothesized that dietary protein deficiency produces cell-mediated immune hypersensitivity in pregnant animals and their offspring akin to those known to produce tissue damage. We compared the effects of feeding a 20% protein diet (controls) to those of feeding a 10% protein (deficient) diet ad libitum to pregnant BALB/c mice. We measured dermal contact sensitivity to 2,4-dinitrofluorobenzene (DNFB) by the increment in ear skin thickness (swelling) 72 h after immunization and parity by the number of viable pups delivered. Dams fed the protein-deficient diet ingested less food, gained less weight and delivered fewer viable pups than the dams fed the control diet. Greater DNFB-stimulated increment in ear skin thickness was found in the protein-deficient mothers and in their offspring than in the control mothers and their offspring. We conclude that dietary protein deficiency limits parity and induces immune hypersensitivity. These findings suggest the potential for dietary protein deficiency to activate a T-cell-mediated branch of the immune response that may put pregnant animals at risk for preterm delivery.

  3. CCK Response Deficiency in Synphilin-1 Transgenic Mice.

    PubMed

    Smith, Wanli W; Smith, Megan; Yang, Dejun; Choi, Pique P; Moghadam, Alexander; Li, Tianxia; Moran, Timothy H

    2015-01-01

    Previously, we have identified a novel role for the cytoplasmic protein, synphilin-1(SP1), in the controls of food intake and body weight in both mice and Drosophila. Ubiquitous overexpression of human SP1 in brain neurons in transgenic mice results in hyperphagia expressed as an increase in meal size. However, the mechanisms underlying this action of SP1 remain to be determined. Here we investigate a potential role for altered gut feedback signaling in the effects of SP1 on food intake. We examined responses to peripheral administration of cholecytokinin (CCK), amylin, and the glucagon like peptide-1 (GLP-1) receptor agonist, exendin-4. Intraperitoneal administration of CCK at doses ranging from 1-10 nmol/kg significantly reduced glucose intake in wild type (WT) mice, but failed to affect intake in SP1 transgenic mice. Moreover, there was a significant attenuation of CCK-induced c-Fos expression in the dorsal vagal complex in SP1 transgenic mice. In contrast, WT and SP1 transgenic mice were similarly responsive to both amylin and exendin-4 treatment. These studies demonstrate that SP1 results in a CCK response deficiency that may contribute to the increased meal size and overall hyperphagia in synphillin-1 transgenic mice.

  4. Estrogen deficiency heterogeneously affects tissue specific stem cells in mice

    PubMed Central

    Kitajima, Yuriko; Doi, Hanako; Ono, Yusuke; Urata, Yoshishige; Goto, Shinji; Kitajima, Michio; Miura, Kiyonori; Li, Tao-Sheng; Masuzaki, Hideaki

    2015-01-01

    Postmenopausal disorders are frequently observed in various organs, but their relationship with estrogen deficiency and mechanisms remain unclear. As tissue-specific stem cells have been found to express estrogen receptors, we examined the hypothesis that estrogen deficiency impairs stem cells, which consequently contributes to postmenopausal disorders. Six-week-old C57BL/6 female mice were ovariectomized, following which they received 17β-estradiol replacement or vehicle (control). Sham-operated mice were used as healthy controls. All mice were killed for evaluation 2 months after treatments. Compared with the healthy control, ovariectomy significantly decreased uterine weight, which was partially recovered by 17β-estradiol replacement. Ovariectomy significantly increased the numbers of c-kit-positive hematopoietic stem/progenitor cells in bone marrow, but impaired their capacity to grow mixed cell-type colonies in vitro. Estrogen replacement further increased the numbers of c-kit-positive hematopoietic stem/progenitor cells in bone marrow, without significantly affecting colony growth in vitro. The number of CD105-positive mesenchymal stem cells in bone marrow also significantly decreased after ovariectomy, but completely recovered following estrogen replacement. Otherwise, neither ovariectomy nor estrogen replacement changed the number of Pax7-positive satellite cells, which are a skeletal muscle-type stem cell. Estrogen deficiency heterogeneously affected tissue-specific stem cells, suggesting a likely and direct relationship with postmenopausal disorders. PMID:26245252

  5. Hippocampus-dependent learning in SKAP-HOM deficient mice.

    PubMed

    Fiedler, Anna; Grecksch, Gisela; Reinhold, Annegret; Schraven, Burkhart; Becker, Axel

    2014-08-15

    SKAP-HOM is an adapter protein which regulates the cross-talk between immunoreceptors and integrins and is involved in signal transduction. It is present in murine brain structures such as the hippocampus, frontal cortex, and cerebellum. In the present study we investigated types of hippocampus-dependent learning (fear conditioning, social memory, and the Morris Water Maze) and locomotor sensitization to amphetamine in transgenic SKAP-HOM deficient mice (-/-) in comparison with respective controls (+/+). Animals from both groups showed comparable fear conditioning, and the extinction of conditioned fear was accelerated in -/-. In terms of sociability, there were no differences between the animals, but in -/- mice social memory was impaired. There was no difference between the two groups of mice in spatial learning and memory measured in the Morris Water Maze. Wild-type and deficient animals exhibited similar sensitization to amphetamine. In reaction to amphetamine challenge, the response in +/+ was enhanced. It was hypothesized that SKAP-HOM deficiency does not affect hippocampus-dependent learning in general, but that its effects on cognitive tasks seem to be dependent on the nature of the cognitive task, i.e. spatial vs. non-spatial.

  6. Lack of global epigenetic methylation defects in CBS deficient mice.

    PubMed

    Lee, Hyung-Ok; Wang, Liqun; Kuo, Yin-Ming; Gupta, Sapna; Slifker, Michael J; Li, Yue-Sheng; Andrews, Andrew J; Kruger, Warren D

    2017-01-01

    Cystathionine β-synthase (CBS) deficiency is a recessive inborn error of metabolism in which patients have extremely elevated plasma total homocysteine and have clinical manifestations in the vascular, visual, skeletal, and nervous systems. Homocysteine is an intermediary metabolite produced from the hydrolysis of S-adenosylhomocysteine (SAH), which is a by-product of methylation reactions involving the methyl-donor S-adenosylmethionine (SAM). Here, we have measured SAM, SAH, DNA and histone methylation status in an inducible mouse model of CBS deficiency to test the hypothesis that homocysteine-related phenotypes are caused by inhibition of methylation due to elevated SAH and reduced SAM/SAH ratio. We found that mice lacking CBS have elevated cellular SAH and reduced SAM/SAH ratios in both liver and kidney, but this was not associated with alterations in the level of 5-methylcytosine or various histone modifications. Using methylated DNA immunoprecipitation in combination with microarray, we found that of the 241 most differentially methylated promoter probes, 89 % were actually hypermethylated in CBS deficient mice. In addition, we did not find that changes in DNA methylation correlated well with changes in RNA expression in the livers of induced and uninduced CBS mice. Our data indicates that reduction in the SAM/SAH ratio, due to loss of CBS activity, does not result in overall hypomethylation of either DNA or histones.

  7. Lessons learned from mice deficient in lectin complement pathway molecules.

    PubMed

    Genster, Ninette; Takahashi, Minoru; Sekine, Hideharu; Endo, Yuichi; Garred, Peter; Fujita, Teizo

    2014-10-01

    The lectin pathway of the complement system is initiated when the pattern-recognition molecules, mannose-binding lectin (MBL), ficolins or collectin-11, bind to invading pathogens or damaged host cells. This leads to activation of MBL/ficolin/collectin-11 associated serine proteases (MASPs), which in turn activate downstream complement components, ultimately leading to elimination of the pathogen. Mice deficient in the key molecules of lectin pathway of complement have been generated in order to build knowledge of the molecular mechanisms of the lectin pathway in health and disease. Despite differences in the genetic arrangements of murine and human orthologues of lectin pathway molecules, the knockout mice have proven to be valuable models to explore the effect of deficiency states in humans. In addition, new insight and unexpected findings on the diverse roles of lectin pathway molecules in complement activation, pathogen infection, coagulation, host tissue injury and developmental biology have been revealed by in vivo investigations. This review provides an overview of the mice deficient in lectin pathway molecules and highlights some of the most important findings that have resulted from studies of these. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Ferroportin deficiency impairs manganese metabolism in flatiron mice

    PubMed Central

    Seo, Young Ah; Wessling-Resnick, Marianne

    2015-01-01

    We examined the physiologic role of ferroportin (Fpn) in manganese (Mn) export using flatiron (ffe/+) mice, a genetic model of Fpn deficiency. Blood (0.0123 vs. 0.0107 mg/kg; P = 0.0003), hepatic (1.06 vs. 0.96 mg/kg; P = 0.0125), and bile Mn levels (79 vs. 38 mg/kg; P = 0.0204) were reduced in ffe/+ mice compared to +/+ controls. Erythrocyte Mn–superoxide dismutase was also reduced at 6 (0.154 vs. 0.096, P = 0.0101), 9 (0.131 vs. 0.089, P = 0.0162), and 16 weeks of age (0.170 vs. 0.090 units/mg protein/min; P < 0.0001). 54Mn uptake after intragastric gavage was markedly reduced in ffe/+ mice (0.0187 vs. 0.0066% dose; P = 0.0243), while clearance of injected isotope was similar in ffe/+ and +/+ mice. These values were compared to intestinal absorption of 59Fe, which was significantly reduced in ffe/+ mice (8.751 vs. 3.978% dose; P = 0.0458). The influence of the ffe mutation was examined in dopaminergic SH-SY5Y cells and human embryonic HEK293T cells. While expression of wild-type Fpn reversed Mn-induced cytotoxicity, ffe mutant H32R failed to confer protection. These combined results demonstrate that Fpn plays a central role in Mn transport and that flatiron mice provide an excellent genetic model to explore the role of this exporter in Mn homeostasis.—Seo, Y. A., Wessling-Resnick, M. Ferroportin deficiency impairs manganese metabolism in flatiron mice. PMID:25782988

  9. Wfs1-deficient mice display impaired behavioural adaptation in stressful environment.

    PubMed

    Luuk, Hendrik; Plaas, Mario; Raud, Sirli; Innos, Jürgen; Sütt, Silva; Lasner, Helena; Abramov, Urho; Kurrikoff, Kaido; Kõks, Sulev; Vasar, Eero

    2009-03-17

    Wfs1-deficient mice were generated by disrupting the 8th exon of Wfs1 gene. Reproduction rates of homozygous Wfs1-deficient mice were slightly below the expected values, they displayed intolerance to glucose and overall lower body weight. The present behavioural study was performed in female Wfs1-deficient mice due to their milder metabolic disturbances. Non-fasting blood glucose levels did not differ between homozygous Wfs1-deficient mice and wild-type littermates. While there was no difference in baseline plasma corticosterone, exposure to stress induced a nearly three-fold elevation of corticosterone in Wfs1-deficient mice in relation to wild-type littermates. Wfs1-deficient mice did not display obvious shortcomings in sensory and motor functioning as exemplified by intact responses in conditioned learning paradigms and rota-rod test. Locomotor activity of Wfs1-deficient mice was significantly lower only in brightly lit environment. Short-term isolation had a significant anxiogenic-like effect on the behaviour of Wfs1-deficient mice in dark/light exploration test. Lower exploratory activity of Wfs1-deficient mice in the plus-maze was antagonised by pre-treatment with diazepam (1 mg/kg), a GABA(A) receptor agonist. Wfs1-deficient mice displayed increased anxiety-like behaviour in hyponeophagia test. The locomotor stimulatory effects of amphetamine (2.5-7.5 mg/kg) and apomorphine (3 mg/kg) were significantly attenuated and facilitated, respectively, in Wfs1-deficient mice. There were no differences between Wfs1-deficient mice and wild-types in forced swimming behaviour and conditioned fear responses. Subtle impairments in reversal learning were apparent in Wfs1-deficient mice in the Morris water maze. Altogether, the present study demonstrates impaired behavioural adaptation of Wfs1-deficient mice in stress-inducing situations. It is likely that Wfs1 protein plays a major role in the behavioural adaptation mechanisms to novel and stressful environments.

  10. Immune-mediated experimental arthritis in IL-33 deficient mice.

    PubMed

    Talabot-Ayer, Dominique; Martin, Praxedis; Seemayer, Christian Alexander; Vigne, Solenne; Lamacchia, Céline; Finckh, Axel; Saiji, Essia; Gabay, Cem; Palmer, Gaby

    2014-09-01

    Previous work suggested implication of the interleukin (IL)-1 family cytokine IL-33, signaling through its receptor ST2, in the pathogenesis of human and mouse arthritis. In this study, we directly investigated the role of endogenous IL-33 in antigen-induced arthritis (AIA) and collagen-induced arthritis (CIA) using IL-33 KO mice. AIA was induced by injection of methylated bovine serum albumin (mBSA) into knee joints of previously immunized mice. CIA was induced by immunization with bovine type II collagen. Disease severity was evaluated by clinical and histological scoring and cellular immune responses were assessed in cultured draining lymph node cells. Our results indicate that the development of AIA or CIA, as assessed by clinical or histological evaluation, is not impaired in IL-33 deficient mice. We did not observe any consistent modifications in humoral or cellular immune responses in IL-33 KO mice, although IL-33 deficiency enhanced antigen-specific IFN-γ production, proliferation or IgG2a titers in some experiments, suggesting that endogenous IL-33 may contribute to shaping the adaptive immune response. In conclusion, our data suggest that IL-33 plays a modifying rather than a pivotal role in disease development in two models of immune-mediated arthritis. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Vitamin D deficiency decreases survival of bacterial meningoencephalitis in mice.

    PubMed

    Djukic, Marija; Sostmann, Nadine; Bertsch, Thomas; Mecke, Marianne; Nessler, Stefan; Manig, Anja; Hanisch, Uwe-Karsten; Triebel, Jakob; Bollheimer, L Cornelius; Sieber, Cornel; Nau, Roland

    2015-01-07

    Meningoencephalitis caused by Escherichia coli is associated with high rates of mortality and risk of neurological sequelae in newborns and infants and in older or immunocompromised adults. A high prevalence of neurological disorders has been observed in geriatric populations at risk of hypovitaminosis D. In vivo, we studied the effects of vitamin D3 on survival and the host's immune response in experimental bacterial meningoencephalitis in mice after intracerebral E. coli infection. To produce different systemic vitamin D3 concentrations, mice received a low, standard, or high dietary vitamin D3 supplementation. Bacterial titers in blood, spleen, and brain homogenates were determined. Leukocyte infiltration was assessed by histological scores, and tissue cytokine or chemokine concentrations were measured. Mice fed a diet with low vitamin D3 concentration died earlier than control animals after intracerebral infection. Vitamin D deficiency did not inhibit leukocyte recruitment into the subarachnoid space and did not lead to an increased density of bacteria in blood, spleen, or brain homogenates. The release of proinflammatory interleukin (IL)-6 was decreased and the release of anti-inflammatory IL-10 was increased in mice fed a diet with high vitamin D3 supplementation. Our observations suggest a detrimental role of vitamin D deficiency in bacterial central nervous system infections. Vitamin D may exert immune regulatory functions.

  12. Apolipoprotein E Genotype-Dependent Paradoxical Short-Term Effects of {sup 56}Fe Irradiation on the Brain

    SciTech Connect

    Haley, Gwendolen E.; Villasana, Laura; Dayger, Catherine; Davis, Matthew J.; Raber, Jacob

    2012-11-01

    Purpose: In humans, apolipoprotein E (apoE) is encoded by three major alleles ({epsilon}2, {epsilon}3, and {epsilon}4) and, compared to apoE3, apoE4 increases the risk of developing Alzheimer disease and cognitive impairments following various environmental challenges. Exposure to irradiation, including that of {sup 56}Fe, during space missions poses a significant risk to the central nervous system, and apoE isoform might modulate this risk. Methods and Materials: We investigated whether apoE isoform modulates hippocampus-dependent cognitive performance starting 2 weeks after {sup 56}Fe irradiation. Changes in reactive oxygen species (ROS) can affect cognition and are induced by irradiation. Therefore, after cognitive testing, we assessed hippocampal ROS levels in ex vivo brain slices, using the ROS-sensitive fluorescent probe, dihydroethidium (DHE). Brain levels of 3-nitrotyrosine (3-NT), CuZn superoxide dismutase (CuZnSOD), extracellular SOD, and apoE were assessed using Western blotting analysis. Results: In the water maze, spatial memory retention was impaired by irradiation in apoE2 and apoE4 mice but enhanced by irradiation in apoE3 mice. Irradiation reduced DHE-oxidation levels in the enclosed blade of the dentate gyrus and levels of 3-NT and CuZnSOD in apoE2 but not apoE3 or apoE4 mice. Finally, irradiation increased apoE levels in apoE3 but not apoE2 or apoE4 mice. Conclusions: The short-term effects of {sup 56}Fe irradiation on hippocampal ROS levels and hippocampus-dependent spatial memory retention are apoE isoform-dependent.

  13. Nrf2 deficiency impairs fracture healing in mice.

    PubMed

    Lippross, Sebastian; Beckmann, Rainer; Streubesand, Nadine; Ayub, Ferda; Tohidnezhad, Mersedeh; Campbell, Graeme; Kan, Yuet Wai; Horst, Fischer; Sönmez, Tolga Taha; Varoga, Deike; Lichte, Philipp; Jahr, Holger; Pufe, Thomas; Wruck, Christoph Jan

    2014-10-01

    Oxidative stress plays an important role in wound healing but data relating oxidative stress to fracture healing are scarce. Nuclear factor erythroid 2-related factor 2 (Nrf2) is the major transcription factor that controls the cellular defence essential to combat oxidative stress by regulating the expression of antioxidative enzymes. This study examined the impact of Nrf2 on fracture healing using a standard closed femoral shaft fracture model in wild-type (WT) and Nrf2-knockout (Nrf2-KO)-mice. Healing was evaluated by histology, real-time RT-PCR, µCT and biomechanical measurements. We showed that Nrf2 expression is activated during fracture healing. Bone healing and remodelling were retarded in the Nrf2-KO compared to the WT-mice. Nrf2-KO-mice developed significantly less callus tissue compared to WT-mice. In addition, biomechanical testing demonstrated lower strength against shear stress in the Nrf2-KO-group compared to WT. The expression of vascular endothelial growth factor (VEGF) and osteocalcin is reduced during fracture healing in Nrf2-KO-mice. Taken together, our results demonstrate that Nrf2 deficiency in mice results in impaired fracture healing suggesting that Nrf2 plays an essential role in bone regeneration. Pharmacological activation of Nrf2 may have therapeutic potential for the enhancement of fracture healing.

  14. Matrine ameliorates spontaneously developed colitis in interleukin-10-deficient mice.

    PubMed

    Wu, Cong; Xu, Zheng; Gai, Renhua; Huang, Kehe

    2016-07-01

    Interleukin-10 (IL-10)-deficient mice spontaneously develop T cell-mediated colitis. Previous reports have shown that Matrine may reduce the symptoms of acute colitis induced by trinitrobenzene sulfonic acid (TNBS). However, whether Matrine impacts chronic colitis remains unknown. In this study, we investigated whether Matrine could limit the symptoms of spontaneously developed colitis and its potential molecular mechanisms. IL-10 deficient mice were given Matrine or a PBS control by oral gavage daily for 4weeks and were euthanized at week 2 or week 4. We measured body weight, colon length and weight, and histological scores. We also evaluated the spontaneous secretion of IL-12/23p40, IFN-γ and IL-17 in colon explant cultures as well as IFN-γ and IL-17 secretion in unseparated mesenteric lymph node (MLN) cells, and assessed IFN-γ, IL-17, IL-1β and IL-6 mRNA expression in colon tissue. In addition, we analyzed the proportions of CD4-positive and CD8-positive cells in unseparated MLN cells. Our results show that Matrine-treated mice exhibited better body weight recovery than controls and that histological scores and spontaneously secreted IL-12/23p40, IFN-γ and IL-17 in colon tissue were significantly decreased in treated mice compared with controls. The proportion of CD4-positive cells of MLNs in treated mice was significantly smaller than that in controls at week 4. Both cytokine production and mRNA expression of IFN-γ and IL-17 were significantly reduced in treated mice compared with controls. Taken together, our results indicate that Matrine may ameliorate spontaneously developed chronic colitis and could be considered as a therapeutic alternative for chronic colitis.

  15. Arginase-II Deficiency Extends Lifespan in Mice.

    PubMed

    Xiong, Yuyan; Yepuri, Gautham; Montani, Jean-Pierre; Ming, Xiu-Fen; Yang, Zhihong

    2017-01-01

    The mitochondrial arginase type II (Arg-II) has been shown to interact with ribosomal protein S6 kinase 1 (S6K1) and mitochondrial p66(Shc) and to promote cell senescence, apoptosis and inflammation under pathological conditions. However, the impact of Arg-II on organismal lifespan is not known. In this study, we demonstrate a significant lifespan extension in mice with Arg-II gene deficiency (Arg-II(-/-)) as compared to wild type (WT) control animals. This effect is more pronounced in the females than in the males. The gender difference is associated with higher Arg-II expression levels in the females than in the males in skin and heart at both young and old age. Ablation of Arg-II gene significantly reduces the aging marker p16(INK4a) levels in these tissues of old female mice, whereas in the male mice this effect of Arg-II deficiency is weaker. In line with this observation, age-associated increases in S6K1 signaling and p66(Shc) levels in heart are significantly attenuated in the female Arg-II(-/-) mice. In the male mice, only p66(Shc) but not S6K1 signaling is reduced. In summary, our study demonstrates that Arg-II may play an important role in the acceleration of aging in mice. Genetic disruption of Arg-II in mouse extends lifespan predominantly in females, which relates to inhibition of S6K1, p66(Shc), and p16(INK4a). Thus, Arg-II may represent a promising target to decelerate aging process and extend lifespan as well as to treat age-related diseases.

  16. Accelerated pericyte degeneration and blood–brain barrier breakdown in apolipoprotein E4 carriers with Alzheimer’s disease

    PubMed Central

    Halliday, Matthew R; Rege, Sanket V; Ma, Qingyi; Zhao, Zhen; Miller, Carol A; Winkler, Ethan A

    2016-01-01

    The blood–brain barrier (BBB) limits the entry of neurotoxic blood-derived products and cells into the brain that is required for normal neuronal functioning and information processing. Pericytes maintain the integrity of the BBB and degenerate in Alzheimer’s disease (AD). The BBB is damaged in AD, particularly in individuals carrying apolipoprotein E4 (APOE4) gene, which is a major genetic risk factor for late-onset AD. The mechanisms underlying the BBB breakdown in AD remain, however, elusive. Here, we show accelerated pericyte degeneration in AD APOE4 carriers >AD APOE3 carriers >non-AD controls, which correlates with the magnitude of BBB breakdown to immunoglobulin G and fibrin. We also show accumulation of the proinflammatory cytokine cyclophilin A (CypA) and matrix metalloproteinase-9 (MMP-9) in pericytes and endothelial cells in AD (APOE4 >APOE3), previously shown to lead to BBB breakdown in transgenic APOE4 mice. The levels of the apoE lipoprotein receptor, low-density lipoprotein receptor-related protein-1 (LRP1), were similarly reduced in AD APOE4 and APOE3 carriers. Our data suggest that APOE4 leads to accelerated pericyte loss and enhanced activation of LRP1-dependent CypA–MMP-9 BBB-degrading pathway in pericytes and endothelial cells, which can mediate a greater BBB damage in AD APOE4 compared with AD APOE3 carriers. PMID:25757756

  17. Dynamic imaging of allogeneic adipose-derived regenerative cells transplanted in ischemic hind limb of apolipoprotein E mouse model

    PubMed Central

    Zheng, Yi; Qin, Jinbao; Wang, Xin; Peng, Zhiyou; Hou, Peiyong; Lu, Xinwu

    2017-01-01

    Background Transplantation of allogeneic adipose-derived regenerative cells (ADRCs) is a promising treatment modality for severe ischemic diseases. However, minimal information is available on the in vivo effects, fate, and migration of ADRCs, as well as the mechanisms of their therapeutic angiogenesis. Materials and methods In this study, green fluorescent protein-expressing ADRCs (GFP-ADRCs) were obtained, labeled with acetylated 3-aminopropyltrimethoxysilane (APTS)-coated iron oxide nanoparticles (APTS NPs), and injected into an old apolipoprotein E knockout (ApoE-KO) mouse model with hind limb ischemia. Then, 3.0 T magnetic resonance imaging (MRI) was performed to dynamically trace the role of ADRCs targeting hind limb ischemia in the ApoE-KO mice model. Results Labeled cells were visualized as large hypointense spots in ischemic muscles by serial 3.0 T MRI scans during a 4-week follow-up. The presence of labeled GFP-ADRCs was confirmed by Prussian blue staining and fluorescence microscopy on postmortem specimens. Conclusion This study showed that allogeneic ADRCs offer great potential application for therapeutic angiogenesis in severe ischemic disease based on the efficacy and feasibility of ADRC transplantation and on the available amounts of tissue. PMID:28053524

  18. Oxytocin hypersensitivity in pregnant P-LAP deficient mice.

    PubMed

    Ishii, Masakazu; Naruse, Katsuhiko; Hattori, Akira; Tsujimoto, Masafumi; Ishiura, Shoichi; Numaguchi, Yasushi; Murohara, Toyoaki; Kobayashi, Hiroshi; Mizutani, Shigehiko

    2009-05-08

    Oxytocin (OT) is the strongest uterotonic substance and has been used widely to induce labor. The physiological importance of OT in modulating the initiation and progression of labor remains unclear. In this study, we showed the roles of OT with onset of labor and also the arginine vasopressin (AVP) effect on urine volume in vivo using both wild type (WT) and placental leucine aminopeptidase (P-LAP)-deficient (KO) mice. OT (1, 2, 2.5 U/day) or recombinant P-LAP (0.01 U/day) was continuously infused from gestation day 15.5 in WT and P-LAP KO mice. Duration until onset of labor was observed. Before and after administration of AVP (1 U/day) in WT and P-LAP KO mice, urine volume was measured. A significant shortening of pregnancy term was observed in P-LAP KO mice. Continuous infusion of OT (1 U/day) revealed that P-LAP KO mice resulted in premature delivery (OT hypersensitivity). We could observe a significant decrease of urine volume in P-LAP KO mice by administration of AVP. Administration of recombinant P-LAP in WT mice resulted in the delay of the onset of labor about 1.5 days compared with control mice. Our present study shows that the regulation of the onset of labor mainly depends on OT and its degradation by P-LAP and also the possible role of P-LAP in the regulation of urine output. P-LAP might be involved in the increased OT sensitivity just prior to onset of labor and also in the onset of labor by degradation of OT.

  19. Crybb2 deficiency impairs fertility in female mice

    SciTech Connect

    Gao, Qian; Sun, Li-Li; Xiang, Fen-Fen; Gao, Li; Jia, Yin; Zhang, Jian-Rong; Tao, Hai-Bo; Zhang, Jun-Jie; Li, Wen-Jie

    2014-10-10

    Highlights: • Crybb2 deletion impaired female fertility. • Crybb2 deletion dramatically affected the production of reproduction-related hormones and hormone response. • Crybb2 deletion impaired follicular development and inhibited the proliferation of granulosa cells. • Crybb2 deletion promoted follicular atresia and apoptosis in granulosa cells. - Abstract: Beta-B2-crystallin (CRYBB2), encoded by Crybb2 gene, is a major protein in the mammalian eye lens that plays an important role in maintaining the transparency of the ocular lens. However, CRYBB2 also plays important roles in many extra-lenticular tissues and organs such as the retina, brain and testis. Our previous studies demonstrated that male Crybb2 deficient (Crybb2{sup −/−}) mice have reduced fertility compared with wild-type (WT) mice, while female Crybb2{sup −/−} mice exhibited reduced ovary weights and shorter estrous cycle percentages. Here we specifically investigated the role of CRYBB2 in the female reproductive system. Our studies revealed that ovaries from female Crybb2{sup −/−} mice exhibited significantly reduced numbers of primordial, secondary and pre-ovulatory follicles when compared with WT mice, while the rate of atretic follicles was also increased. Additionally, fewer eggs were collected from the oviduct of Crybb2{sup −/−} female mice after superovulation. Estrogen levels were higher in the metestrus and diestrus cycles of female Crybb2{sup −/−} mice, while progesterone levels were lower in diestrus cycles. Furthermore, the expression of survival and cell cycle genes, Bcl-2, Cdk4 and Ccnd2, were significantly decreased in granulosa cells isolated from female Crybb2{sup −/−} mice, consistent with the predominant expression of CRYBB2 in ovarian granulosa cells. Our results reveal a critical role for CRYBB2 in female fertility and specific effects on the proliferation and survival status of ovarian granulosa cells.

  20. Adaptation of Enterovirus 71 to Adult Interferon Deficient Mice

    PubMed Central

    Caine, Elizabeth A.; Partidos, Charalambos D.; Santangelo, Joseph D.; Osorio, Jorge E.

    2013-01-01

    Non-polio enteroviruses, including enterovirus 71 (EV71), have caused severe and fatal cases of hand, foot and mouth disease (HFMD) in the Asia-Pacific region. The development of a vaccine or antiviral against these pathogens has been hampered by the lack of a reliable small animal model. In this study, a mouse adapted EV71 strain was produced by conducting serial passages through A129 (α/β interferon (IFN) receptor deficient) and AG129 (α/β, γ IFN receptor deficient) mice. A B2 sub genotype of EV71 was inoculated intraperitoneally (i.p.) into neonatal AG129 mice and brain-harvested virus was subsequently passaged through 12 and 15 day-old A129 mice. When tested in 10 week-old AG129 mice, this adapted strain produced 100% lethality with clinical signs including limb paralysis, eye irritation, loss of balance, and death. This virus caused only 17% mortality in same age A129 mice, confirming that in the absence of a functional IFN response, adult AG129 mice are susceptible to infection by adapted EV71 isolates. Subsequent studies in adult AG129 and young A129 mice with the adapted EV71 virus examined the efficacy of an inactivated EV71 candidate vaccine and determined the role of humoral immunity in protection. Passive transfer of rabbit immune sera raised against the EV71 vaccine provided protection in a dose dependent manner in 15 day-old A129 mice. Intramuscular injections (i.m.) in five week-old AG129 mice with the alum adjuvanted vaccine also provided protection against the mouse adapted homologous strain. No clinical signs of disease or mortality were observed in vaccinated animals, which received a prime-and-boost, whereas 71% of control animals were euthanized after exhibiting systemic clinical signs (P<0.05). The development of this animal model will facilitate studies on EV71 pathogenesis, antiviral testing, the evaluation of immunogenicity and efficacy of vaccine candidates, and has the potential to establish correlates of protection studies. PMID

  1. Altered histamine neurotransmission in HPRT-deficient mice.

    PubMed

    Tschirner, Sarah K; Gutzki, Frank; Kaever, Volkhard; Seifert, Roland; Schneider, Erich H

    2015-11-16

    Lesch-Nyhan syndrome (LNS) is an X-chromosomal disorder with congenital deficiency of the purine salvage enzyme hypoxanthine-guanine phosphoribosyltransferase (HPRT) as underlying defect. We determined the concentrations of dopamine, histamine and their metabolites in brains of HPRT knockout mice, which serve as an animal model for LNS, and compared the results to those obtained from wild-type controls. Analyses were performed by high performance liquid chromatography (HPLC)-coupled tandem mass spectrometry (MS/MS). Besides a decrease of dopamine and 3-methoxytyramine (3-MT) concentrations in the cerebral hemisphere, HPRT-deficient mice also exhibited significantly reduced 1-methylhistamine (1-MH) and 1-methylimidazole-4-acetic acid (1-MI4AA) concentrations in the brain hemisphere and medulla. Moreover, the amount of 1-MI4AA was significantly decreased in the cerebellum. Our findings show that neuronal perturbations caused by HPRT deficiency are not restricted to the dopamine system but also affect histaminergic neurotransmission. These new insights into the brain metabolism of an LNS mouse model may help to find new therapeutic strategies to improve the quality of life of LNS patients.

  2. Otoconia-Deficient Mice Show Selective Spatial Deficits

    PubMed Central

    Yoder, Ryan M.; Kirby, Seth L.

    2014-01-01

    Damage or inactivation of the vestibular system impairs performance on various spatial memory tasks, but few studies have attempted to disambiguate the roles of the semicircular canals and otolith organs in this performance. The present study tested the otolithic contribution to spatial working and reference memory by evaluating the performance of otoconia-deficient tilted mice on a radial arm maze and a Barnes maze. One radial arm maze task provided both intramaze and extramaze cues, whereas the other task provided only extramaze cues. The Barnes maze task provided only extramaze cues. On the radial arm maze, tilted mice performed similar to control mice when intramaze cues were available, but made more working and reference memory errors than control mice when only extramaze cues were available. On the Barnes maze task, control and tilted mice showed similar latency, distance, and errors during acquisition training. On the subsequent probe trial, both groups spent the greatest percentage of time in the goal quadrant, indicating they were able to use extramaze cues to guide their search. Overall, these results suggest signals originating in the otolith organs contribute to spatial memory, but are not necessary for all aspects of spatial performance. PMID:24802640

  3. Histidine Decarboxylase Deficiency Prevents Autoimmune Diabetes in NOD Mice

    PubMed Central

    Alkan, Manal; Machavoine, François; Rignault, Rachel; Dam, Julie; Dy, Michel; Thieblemont, Nathalie

    2015-01-01

    Recent evidence has highlighted the role of histamine in inflammation. Since this monoamine has also been strongly implicated in the pathogenesis of type-1 diabetes, we assessed its effect in the nonobese diabetic (NOD) mouse model. To this end, we used mice (inactivated) knocked out for the gene encoding histidine decarboxylase, the unique histamine-forming enzyme, backcrossed on a NOD genetic background. We found that the lack of endogenous histamine in NOD HDC−/− mice decreased the incidence of diabetes in relation to their wild-type counterpart. Whereas the proportion of regulatory T and myeloid-derived suppressive cells was similar in both strains, histamine deficiency was associated with increased levels of immature macrophages, as compared with wild-type NOD mice. Concerning the cytokine pattern, we found a decrease in circulating IL-12 and IFN-γ in HDC−/− mice, while IL-6 or leptin remained unchanged, suggesting that histamine primarily modulates the inflammatory environment. Paradoxically, exogenous histamine given to NOD HDC−/− mice provided also protection against T1D. Our study supports the notion that histamine is involved in the pathogenesis of diabetes, thus providing additional evidence for its role in the regulation of the immune response. PMID:26090474

  4. Runx3 deficiency results in myeloproliferative disorder in aged mice.

    PubMed

    Wang, Chelsia Qiuxia; Motoda, Lena; Satake, Masanobu; Ito, Yoshiaki; Taniuchi, Ichiro; Tergaonkar, Vinay; Osato, Motomi

    2013-07-25

    The RUNX family genes encode transcription factors that are involved in development and human diseases. RUNX1 is one of the most frequently mutated genes in human hematological malignancies and is a critical factor for the generation and maintenance of hematopoietic stem cells. Another Runx family gene, Runx3, is known to be expressed in hematopoietic cells. However, its involvement in hematopoiesis remains unclear. Here we show the hematopoietic phenotypes in Runx3 conditional knockout (KO) mice (Runx3(fl/fl);Mx1-Cre(+)): whereas young Runx3 KO mice did not exhibit any significant hematopoietic defects, aged Runx3 KO mice developed a myeloproliferative disorder characterized by myeloid-dominant leukocytosis, splenomegaly, and an increase of hematopoietic stem/progenitor cells (HSPCs). Notably, Runx3-deficient cells showed hypersensitivity to granulocyte-colony stimulating factor, suggesting enhanced proliferative and mobilization capability of Runx3-deficient HSPCs when stimulated. These results suggest that, besides Runx1, Runx3 also plays a role in hematopoiesis.

  5. Danger-free autoimmune disease in Aire-deficient mice.

    PubMed

    Gray, Daniel H D; Gavanescu, Irina; Benoist, Christophe; Mathis, Diane

    2007-11-13

    The danger theory of immune tolerance asserts that environmental factors hold primacy over lymphocyte autoreactivity in initiating autoimmune disease. We sought to test this contention using the Aire-deficient mouse model of the human disease, autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy, a multiorgan autoimmune disorder rooted in a lesion in thymic tolerance. Compound screens stimulating a broad range of innate immune system pathways failed to show any modulation of disease characteristics in Aire(-/-) mice on either the C57BL/6 or NOD genetic backgrounds. Furthermore, deficiency in the Toll-like receptor adaptor Myd88 increased the lifespan of NOD.aire(-/-) mice but did not prevent the initiation of autoimmunity. Finally, germ-free NOD.aire(-/-) mice exhibited autoimmunity in all organs normally targeted in this model, indicating that microbial conditioning is not required for activation of autoreactive T cells relevant to this disease. Together, these data suggest that the stochastic genesis of dangerous T cell clones can initiate autoimmune disease without the need for environmental stimulation, underlining the importance of Aire-dependent thymic deletion.

  6. Neuropsychiatric symptoms and Apolipoprotein E: Associations with eventual Alzheimer's disease development.

    PubMed

    Burke, Shanna L; Maramaldi, Peter; Cadet, Tamara; Kukull, Walter

    2016-01-01

    Alzheimer's disease (AD) is the result of neurodegeneration, which manifests clinically as deficits in memory, thinking, and behavior. It was hypothesized that neuropsychiatric symptoms and the apolipoprotein E genotype increase the likelihood of Alzheimer's disease development. Utilizing data from the National Alzheimer's Coordinating Center, information from evaluations of 11,453 cognitively intact participants was analyzed. Survival analysis was used to explore relationships between individual neuropsychiatric symptoms as determined by the Neuropsychiatric Inventory Questionnaire, apolipoprotein E, and eventual AD diagnosis. Cox proportional hazard models were utilized to explore the main effects and synergistic (additive and multiplicative) interactions. This study provided evidence for an increased hazard of developing AD among participants with any of the symptoms assessed by the NPI-Q. The hazard of developing AD was almost thirteen times higher for ε4 carriers with delusions and eleven times greater for those with apathy and disinhibition. Statistically significant hazards (p>0.001) were also realized by ε4 carriers with hallucinations; agitation; depression; anxiety; elation; apathy; irritability; and motor, sleep, and appetite disturbances. Findings suggest that neuropsychiatric symptoms are associated with eventual AD diagnosis among a group of cognitively asymptomatic participants at baseline. Many studies begin with a group of participants already impacted by AD diagnosis. The longitudinal analysis of a group of participants who, at baseline, demonstrated no observable signs of AD was a strength of this study. This investigation contributes to the literature exploring an increased hazard of AD due to potential modifiable risk factors and genetic biomarkers such as apolipoprotein E. Copyright © 2016. Published by Elsevier Ireland Ltd.

  7. Neuropsychiatric symptoms and Apolipoprotein E: Associations with eventual Alzheimer’s disease development

    PubMed Central

    Maramaldi, Peter; Cadet, Tamara; Kukull, Walter

    2016-01-01

    Objective Alzheimer’s disease (AD) is the result of neurodegeneration, which manifests clinically as deficits in memory, thinking, and behavior. It was hypothesized that neuropsychiatric symptoms and the apolipoprotein E genotype increase the likelihood of Alzheimer’s disease development. Methods Utilizing data from the National Alzheimer’s Coordinating Center, information from evaluations of 11,453 cognitively intact participants was analyzed. Survival analysis was used to explore relationships between individual neuropsychiatric symptoms as determined by the Neuropsychiatric Inventory Questionnaire, apolipoprotein E, and eventual AD diagnosis. Cox proportional hazard models were utilized to explore the main effects and synergistic (additive and multiplicative) interactions. Results This study provided evidence for an increased hazard of developing AD among participants with any of the symptoms assessed by the NPI-Q. The hazard of developing AD was almost thirteen times higher for ε4 carriers with delusions and eleven times greater for those with apathy and disinhibition. Statistically significant hazards (p > 0.001) were also realized by ε4 carriers with hallucinations; agitation; depression; anxiety; elation; apathy; irritability; and motor, sleep, and appetite disturbances. Conclusions Findings suggest that neuropsychiatric symptoms are associated with eventual AD diagnosis among a group of cognitively asymptomatic participants at baseline. Many studies begin with a group of participants already impacted by AD diagnosis. The longitudinal analysis of a group of participants who, at baseline, demonstrated no observable signs of AD was a strength of this study. This investigation contributes to the literature exploring an increased hazard of AD due to potential modifiable risk factors and genetic biomarkers such as apolipoprotein E. PMID:27111252

  8. Analysis of cell surface alterations in Legionella pneumophila cells treated with human apolipoprotein E.

    PubMed

    Palusinska-Szysz, Marta; Zdybicka-Barabas, Agnieszka; Cytryńska, Małgorzata; Wdowiak-Wróbel, Sylwia; Chmiel, Elżbieta; Gruszecki, Wiesław I

    2015-03-01

    Binding of human apolipoprotein E (apoE) to Legionella pneumophila lipopolysaccharide was analysed at the molecular level by Fourier-transform infrared spectroscopy, thereby providing biophysical evidence for apoE-L. pneumophila lipopolysaccharide interaction. Atomic force microscopy imaging of apoE-exposed L. pneumophila cells revealed alterations in the bacterial cell surface topography and nanomechanical properties in comparison with control bacteria. The changes induced by apoE binding to lipopolysaccharide on the surface of L. pneumophila cells may participate in: (1) impeding the penetration of host cells by the bacteria; (2) suppression of pathogen intracellular growth and eventually; and (3) inhibition of the development of infection.

  9. Application of denaturing gradient gel electrophoresis to detect DNA sequence differences encoding apolipoprotein E isoforms

    SciTech Connect

    Parker, S.; Angelico, M.C.; Laffel, L.; Krolewski, A.S. Harvard Medical School, Boston, MA )

    1993-04-01

    Apolipoprotein E (apoE) plays an important role in plasma lipid metabolism. Three common isoforms of this protein have been identified by the isoelectric focusing method. In this report the authors describe a new method for distinguishing these isoforms. Their method employs PCR amplification of the DNA sequence of exon 4 in the apoE gene followed by denaturing gradient gel electrophoresis (DGGE) to distinguish its different melting characteristics. Identification of the ApoE isoforms through DNA melting behavior rather than protein charge differences eliminates the problems associated with isoelectric focusing and facilitates screening for additional mutations at the apoE locus. 12 refs., 2 figs.

  10. Evidence of Adrenal Failure in Aging Dax1-Deficient Mice

    PubMed Central

    Scheys, Joshua O.; Heaton, Joanne H.

    2011-01-01

    Dosage-sensitive sex reversal, adrenal hypoplasia congenita (AHC) critical region on the X chromosome, gene 1 (Dax1) is an orphan nuclear receptor essential for development and function of the mammalian adrenal cortex and gonads. DAX1 was cloned as the gene responsible for X-linked AHC, which is characterized by adrenocortical failure necessitating glucocorticoid replacement. Contrary to these human data, young mice with genetic Dax1 knockout (Dax1−/Y) exhibit adrenocortical hyperfunction, consistent with the historic description of Dax1 as a transcriptional repressor that inhibits steroidogenic factor 1-dependent steroidogenesis. This paradox of molecular function and two apparently opposite phenotypes associated with Dax1 deficiency in mice and humans is compounded by the recent observations that under certain circumstances, Dax1 can serve as a transcriptional activator of steroidogenic factor 1. The recently revealed role of Dax1 in embryonic stem cell pluripotency, together with the observation that its expression in the adult adrenal is restricted to the subcapsular cortex, where presumptive undifferentiated progenitor cells reside, has led us to reexamine the phenotype of Dax1−/Y mice in order to reconcile the conflicting mouse and human data. In this report, we demonstrate that although young Dax1−/Y mice have enhanced steroidogenesis and subcapsular adrenocortical proliferation, as these mice age, they exhibit declining adrenal growth, decreasing adrenal steroidogenic capacity, and a reversal of their initial enhanced hormonal sensitivity. Together with a marked adrenal dysplasia in aging mice, these data reveal that both Dax1−/Y mice and patients with X-linked AHC exhibit adrenal failure that is consistent with adrenocortical subcapsular progenitor cell depletion and argue for a significant role of Dax1 in maintenance of these cells. PMID:21733829

  11. Bilberry anthocyanin-rich extract alters expression of genes related to atherosclerosis development in aorta of apo E-deficient mice.

    PubMed

    Mauray, A; Felgines, C; Morand, C; Mazur, A; Scalbert, A; Milenkovic, D

    2012-01-01

    Intake of anthocyanin-rich foods has been associated with a reduced risk of cardiovascular diseases. We recently reported that a nutritional supplementation with a bilberry anthocyanin-rich extract (BE) attenuates atherosclerotic lesion development in apolipoprotein E-deficient (apoE⁻/⁻) mice. However, the mechanism(s) of their preventive action are not completely understood. Anthocyanins may alter mRNA levels of genes related to atherosclerosis in cultured macrophages and endothelial cells, but in vivo studies remain scarce. The aim of the present study was to explore the in vivo mechanisms of action of the same bilberry extract, administered by supplementation at a nutritional level, in the aorta of apo E⁻/⁻ mice using a global transcriptomic approach. This study focused on the early stage of atherosclerosis development for better assessment of BE action on initiation mechanisms of this pathology. After a two week period, plasma lipid and antioxidant capacity were evaluated and the global genomic analysis was carried out using pangenomic microarrays. BE supplementation significantly improved hypercholesterolemia whereas the plasmatic antioxidant status remained unchanged. Nutrigenomic analysis identified 1261 genes which expression was modulated by BE in the aorta. Bioinformatic analysis revealed that these genes are implicated in different cellular processes such as oxidative stress, inflammation, transendothelial migration and angiogenesis, processes associated with atherosclerosis development/protection. Some of the most significantly down-regulated genes included genes coding for AOX1, CYP2E1 or TXNIP implicated in the regulation of oxidative stress, JAM-A coding for adhesion molecules or VEGFR2 implicate in regulation of angiogenesis. Other genes were up-regulated, such as CRB3, CLDN14 or CDH4 potentially associated with increased cell-cell adhesion and decreased paracellular permeability. These results provide a global integrated view of the

  12. Clostridium difficile infection aggravates colitis in interleukin 10-deficient mice

    PubMed Central

    Kim, Mi Na; Koh, Seong-Joon; Kim, Jung Mogg; Im, Jong Pil; Jung, Hyun Chae; Kim, Joo Sung

    2014-01-01

    AIM: To investigate the effect of Clostridium difficile (C. difficile) infection in an interleukin 10-deficient (IL-10-/-) mouse model of inflammatory bowel disease. METHODS: Bone marrow-derived dendritic cells isolated from wild type (WT) and IL-10-/-mice were stimulated for 4 h with C. difficile toxin A (200 μg/mL), and gene expression of interferon (IFN)-γ, IL-12 and IL-23 was determined by real-time reverse transcription polymerase chain reaction. WT and IL-10-/- mice (n = 20 each) were exposed to an antibiotic cocktail for three days and then were injected with clindamycin (i.p.). Mice (n = 10 WT, 10 IL-10-/-) were then challenged with oral administration of C. difficile (1 × 105 colony forming units of strain VPI 10463). Animals were monitored daily for 7 d for signs of colitis. Colonic tissue samples were evaluated for cytokine gene expression and histopathologic analysis. RESULTS: C. difficile toxin A treatment induced IFN-γ gene expression to a level that was significantly higher in BDMCs from IL-10-/- compared to those from WT mice (P < 0.05). However, expression of IL-12 and IL-23 was not different among the groups. Following C. difficile administration, mice developed diarrhea and lost weight within 2-3 d. Weight loss was significantly greater in IL-10-/- compared to WT mice (P < 0.05). C. difficile infection induced histopathologic features typical of colitis in both IL-10-/- and WT mice. The histopathologic severity score was significantly higher in the IL-10-/- than in WT mice (mean ± standard error; 5.50 ± 0.53 vs 2.44 ± 0.46; P < 0.05). This was accompanied by a significantly greater increase in IFN-γ gene expression in colonic tissues from IL-10-/- than from WT mice challenged with C. difficile (P < 0.05). CONCLUSION: These results indicate that colitis is more severe after C. difficile infection in IL-10-/-mice, and that IFN-γ expression is involved in this process. PMID:25493020

  13. Heterozygote Wdr36-deficient mice do not develop glaucoma.

    PubMed

    Gallenberger, Martin; Kroeber, Markus; März, Loreen; Koch, Marcus; Fuchshofer, Rudolf; Braunger, Barbara M; Iwata, Takeshi; Tamm, Ernst R

    2014-11-01

    There is an ongoing controversy regarding the role of WDR36 sequence variants in the pathogenesis of primary open-angle glaucoma (POAG). WDR36 is a nucleolar protein involved in the maturation of 18S rRNA. The function of WDR36 is essential as homozygous Wdr36-deficient mouse embryos die before reaching the blastocyst stage. Here we provide a detailed analysis of the phenotype of heterozygous Wdr36-deficient mice. Loss of one Wdr36 allele causes a substantial reduction in the expression of Wdr36 mRNA. In the eyes of Wdr36(+/-) animals, the structure of the tissues involved in aqueous humor circulation and of the optic nerve head are not different from that of control littermates. In addition, one-year-old Wdr36(+/-) animals do not differ from wild-type animals with regards to intraocular pressure and number of optic nerve axons. The susceptibility of retinal ganglion cells to excitotoxic damage induced by NMDA is similar in Wdr36(+/-) and wild-type animals. Moreover, the amount of optic nerve axonal damage induced by high IOP is not different between Wdr36(+/-) and wild-type mice. Transgenic overexpression of mutated Del605-607 Wdr36 in Wdr36(+/-) animals does not cause changes in the number of optic nerve axons or susceptibility to excitotoxic damage. In addition, analysis of 18S rRNA maturation in Del605-607 Wdr36(+/-) or Wdr36(+/-) mice does not show obvious differences in rRNA processing or in the amounts of precursor forms when compared to wild-type animals. Our data obtained in Wdr36(+/-) mice do not support the assumption of a causative role for WDR36 in the pathogenesis of POAG. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Pineal melatonin synthesis is altered in Period1 deficient mice.

    PubMed

    Christ, E; Pfeffer, M; Korf, H W; von Gall, C

    2010-12-01

    Melatonin is an important endocrine signal for darkness in mammals. Transcriptional activation of the arylalkylamine-N-acetyltransferase gene encoding for the penultimate enzyme in melatonin synthesis drives the daily rhythm of the hormone in the pineal gland of rodents. Rhythmic arylalkylamine-N-acetyltransferase expression is controlled by the cAMP-signal transduction pathway and involves the activation of β-adrenergic receptors and the inducible cAMP early repressor. In addition, the rat arylalkylamine-N-acetyltransferase promoter contains an E-box element which can interact with clock proteins. Moreover, the pineal gland of mice shows a circadian rhythm in clock proteins such as the transcriptional repressor Period1, which has been shown to control rhythmic gene expression in a variety of tissues. However, the role of Period1 in the regulation of pineal melatonin synthesis is still unknown. Therefore, circadian rhythms in arylalkylamine-N-acetyltransferase, β-adrenergic receptor, and inducible cAMP early repressor mRNA levels (real time PCR), arylalkylamine-N-acetyltransferase enzyme activity (radiometric assay) and melatonin concentration radio immuno assay (RIA) were analyzed in the pineal gland of mice with a targeted deletion of the Period1 gene (Per1-/-) and the corresponding wildtype. In Per1-/- the amplitude in arylalkylamine-N-acetyltransferase expression was significantly elevated as compared to wildtype. In contrast, β-adrenergic receptor and inducible cAMP early repressor mRNA levels were not affected by the Period1-deficiency. This indicates that the molecular clockwork alters the amplitude of arylalkylamine-N-acetyltransferase expression. In vitro, pineal glands of Per1-/- mice showed a day night difference in arylalkylamine-N-acetyltransferase expression with high levels at night. This suggests that a deficient in Period1 elicits similar effects as the activation of the cAMP-signal transduction pathway in wildtype mice.

  15. COMPOSITION OF MINERALIZING INCISOR ENAMEL IN CFTR-DEFICIENT MICE

    PubMed Central

    Bronckers, ALJJ; Lyaruu, DM; Guo, J; Bijvelds, MJC; Bervoets, TJM; Zandieh-Doulabi, B; Medina, JF; Li, Z; Zhang, Y; DenBesten, PK

    2014-01-01

    Formation of crystals in the enamel space releases protons that need to be buffered to sustain mineral accretion. We hypothesized that apical Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) in maturation ameloblasts transduces chloride into forming enamel as critical step to secrete bicarbonates. We tested this by determining the calcium, chloride and fluoride levels of developing enamel of Cftr-null mice by quantitative electron probe microanalysis. Maturation stage Cftr–null enamel contained less chloride and calcium than wild-type enamel, was more acidic when stained with pH dyes ex vivo and formed no fluorescent modulation bands after in vivo injection of the mice with calcein. To further acidify the enamel we exposed Cftr-null mice to fluoride in drinking water to stimulate proton release during formation of hypermineralized lines. In enamel of Cftr-deficient mice fluoride further lowered enamel calcium without further reducing chloride levels. The data support the view that apical Cftr in maturation ameloblasts transduces chloride into developing enamel as part of the machinery to buffer protons released during mineral accretion. PMID:25557910

  16. Enhanced cartilage regeneration in MIA/CD-RAP deficient mice.

    PubMed

    Schmid, R; Schiffner, S; Opolka, A; Grässel, S; Schubert, T; Moser, M; Bosserhoff, A-K

    2010-11-11

    Melanoma inhibitory activity/cartilage-derived retinoic acid-sensitive protein (MIA/CD-RAP) is a small soluble protein secreted from chondrocytes. It was identified as the prototype of a family of extracellular proteins adopting an SH3 domain-like fold. In order to study the consequences of MIA/CD-RAP deficiency in detail we used mice with a targeted gene disruption of MIA/CD-RAP (MIA-/-) and analyzed cartilage organisation and differentiation in in vivo and in vitro models. Cartilage formation and regeneration was determined in models for osteoarthritis and fracture healing in vivo, in addition to in vitro studies using mesenchymal stem cells of MIA-/- mice. Interestingly, our data suggest enhanced chondrocytic regeneration in the MIA-/- mice, modulated by enhanced proliferation and delayed differentiation. Expression analysis of cartilage tissue derived from MIA-/- mice revealed strong downregulation of nuclear RNA-binding protein 54-kDa (p54(nrb)), a recently described modulator of Sox9 activity. In this study, we present p54(nrb) as a mediator of MIA/CD-RAP to promote chondrogenesis. Taken together, our data indicate that MIA/CD-RAP is required for differentiation in cartilage potentially by regulating signaling processes during differentiation.

  17. Enhanced cartilage regeneration in MIA/CD-RAP deficient mice

    PubMed Central

    Schmid, R; Schiffner, S; Opolka, A; Grässel, S; Schubert, T; Moser, M; Bosserhoff, A-K

    2010-01-01

    Melanoma inhibitory activity/cartilage-derived retinoic acid-sensitive protein (MIA/CD-RAP) is a small soluble protein secreted from chondrocytes. It was identified as the prototype of a family of extracellular proteins adopting an SH3 domain-like fold. In order to study the consequences of MIA/CD-RAP deficiency in detail we used mice with a targeted gene disruption of MIA/CD-RAP (MIA−/−) and analyzed cartilage organisation and differentiation in in vivo and in vitro models. Cartilage formation and regeneration was determined in models for osteoarthritis and fracture healing in vivo, in addition to in vitro studies using mesenchymal stem cells of MIA−/− mice. Interestingly, our data suggest enhanced chondrocytic regeneration in the MIA−/− mice, modulated by enhanced proliferation and delayed differentiation. Expression analysis of cartilage tissue derived from MIA−/− mice revealed strong downregulation of nuclear RNA-binding protein 54-kDa (p54nrb), a recently described modulator of Sox9 activity. In this study, we present p54nrb as a mediator of MIA/CD-RAP to promote chondrogenesis. Taken together, our data indicate that MIA/CD-RAP is required for differentiation in cartilage potentially by regulating signaling processes during differentiation. PMID:21368873

  18. Morphological study of tooth development in podoplanin-deficient mice

    PubMed Central

    Takara, Kenyo; Maruo, Naoki; Oka, Kyoko; Kaji, Chiaki; Hatakeyama, Yuji; Sawa, Naruhiko; Kato, Yukinari; Yamashita, Junro; Kojima, Hiroshi; Sawa, Yoshihiko

    2017-01-01

    Podoplanin is a mucin-type highly O-glycosylated glycoprotein identified in several somatyic cells: podocytes, alveolar epithelial cells, lymphatic endothelial cells, lymph node stromal fibroblastic reticular cells, osteocytes, odontoblasts, mesothelial cells, glia cells, and others. It has been reported that podoplanin-RhoA interaction induces cytoskeleton relaxation and cell process stretching in fibroblastic cells and osteocytes, and that podoplanin plays a critical role in type I alveolar cell differentiation. It appears that podoplanin plays a number of different roles in contributing to cell functioning and growth by signaling. However, little is known about the functions of podoplanin in the somatic cells of the adult organism because an absence of podoplanin is lethal at birth by the respiratory failure. In this report, we investigated the tooth germ development in podoplanin-knockout mice, and the dentin formation in podoplanin-conditional knockout mice having neural crest-derived cells with deficiency in podoplanin by the Wnt1 promoter and enhancer-driven Cre recombinase: Wnt1-Cre;PdpnΔ/Δmice. In the Wnt1-Cre;PdpnΔ/Δmice, the tooth and alveolar bone showed no morphological abnormalities and grow normally, indicating that podoplanin is not critical in the development of the tooth and bone. PMID:28222099

  19. Iron overload diminishes atherosclerosis in apoE-deficient mice

    PubMed Central

    Kirk, Elizabeth A.; Heinecke, Jay W.; LeBoeuf, Renée C.

    2001-01-01

    It has been proposed that elevated levels of tissue iron increase the risk for atherosclerosis, perhaps by favoring the formation of pro-atherogenic oxidized LDL. Working with apoE-deficient (apoE–/–) mice, which do not require a high-fat diet to develop atherosclerosis, we compared the effects of standard diet (0.02% iron) or a 2% carbonyl iron diet. After 24 weeks, mice fed the 2% carbonyl iron diet had twice as much iron in their plasma, a ninefold increase in bleomycin-detectable free iron in their plasma, and ten times as much iron in their livers as control mice. Dietary iron overload caused a modest (30%) rise in plasma triglyceride and cholesterol. Nevertheless, this regimen did not exacerbate, but rather reduced the severity of atherosclerosis by 50%, and it failed to elevate hepatic levels of heme oxygenase mRNA, which is induced by many different oxidative insults in vitro. Moreover, hepatic levels of protein-bound dityrosine and ortho-tyrosine, two markers of metal-catalyzed oxidative damage in vitro, failed to rise in iron-overloaded animals. Our observations suggest that elevated serum and tissue levels of iron are not atherogenic in apoE–/– mice. Moreover, they call into question the hypothesis that elevated levels of tissue iron promote LDL oxidation and oxidative stress in vivo. PMID:11413162

  20. Morphological study of tooth development in podoplanin-deficient mice.

    PubMed

    Takara, Kenyo; Maruo, Naoki; Oka, Kyoko; Kaji, Chiaki; Hatakeyama, Yuji; Sawa, Naruhiko; Kato, Yukinari; Yamashita, Junro; Kojima, Hiroshi; Sawa, Yoshihiko

    2017-01-01

    Podoplanin is a mucin-type highly O-glycosylated glycoprotein identified in several somatyic cells: podocytes, alveolar epithelial cells, lymphatic endothelial cells, lymph node stromal fibroblastic reticular cells, osteocytes, odontoblasts, mesothelial cells, glia cells, and others. It has been reported that podoplanin-RhoA interaction induces cytoskeleton relaxation and cell process stretching in fibroblastic cells and osteocytes, and that podoplanin plays a critical role in type I alveolar cell differentiation. It appears that podoplanin plays a number of different roles in contributing to cell functioning and growth by signaling. However, little is known about the functions of podoplanin in the somatic cells of the adult organism because an absence of podoplanin is lethal at birth by the respiratory failure. In this report, we investigated the tooth germ development in podoplanin-knockout mice, and the dentin formation in podoplanin-conditional knockout mice having neural crest-derived cells with deficiency in podoplanin by the Wnt1 promoter and enhancer-driven Cre recombinase: Wnt1-Cre;PdpnΔ/Δmice. In the Wnt1-Cre;PdpnΔ/Δmice, the tooth and alveolar bone showed no morphological abnormalities and grow normally, indicating that podoplanin is not critical in the development of the tooth and bone.

  1. Impaired theta-gamma coupling in APP-deficient mice

    PubMed Central

    Zhang, Xiaomin; Zhong, Wewei; Brankačk, Jurij; Weyer, Sascha W.; Müller, Ulrike C.; Tort, Adriano B. L.; Draguhn, Andreas

    2016-01-01

    Amyloid precursor protein (APP) is critically involved in the pathophysiology of Alzheimer’s disease, but its physiological functions remain elusive. Importantly, APP knockout (APP-KO) mice exhibit cognitive deficits, suggesting that APP plays a role at the neuronal network level. To investigate this possibility, we recorded local field potentials (LFPs) from the posterior parietal cortex, dorsal hippocampus and lateral prefrontal cortex of freely moving APP-KO mice. Spectral analyses showed that network oscillations within the theta- and gamma-frequency bands were not different between APP-KO and wild-type mice. Surprisingly, however, while gamma amplitude coupled to theta phase in all recorded regions of wild-type animals, in APP-KO mice theta-gamma coupling was strongly diminished in recordings from the parietal cortex and hippocampus, but not in LFPs recorded from the prefrontal cortex. Thus, lack of APP reduces oscillatory coupling in LFP recordings from specific brain regions, despite not affecting the amplitude of the oscillations. Together, our findings reveal reduced cross-frequency coupling as a functional marker of APP deficiency at the network level. PMID:26905287

  2. Helicobacter cinaedi induced typhlocolitis in Rag-2-deficient mice.

    PubMed

    Shen, Zeli; Feng, Yan; Rickman, Barry; Fox, James G

    2015-04-01

    Helicobacter cinaedi, an enterohepatic helicobacter species (EHS), is an important human pathogen and is associated with a wide range of diseases, especially in immunocompromised patients. It has been convincingly demonstrated that innate immune response to certain pathogenic enteric bacteria is sufficient to initiate colitis and colon carcinogenesis in recombinase-activating gene (Rag)-2-deficient mice model. To better understand the mechanisms of human IBD and its association with development of colon cancer, we investigated whether H. cinaedi could induce pathological changes noted with murine enterohepatic helicobacter infections in the Rag2(-/-) mouse model. Sixty 129SvEv Rag2(-/-) mice mouse were experimentally or sham infected orally with H. cinaedi strain CCUG 18818. Gastrointestinal pathology and immune responses in infected and control mice were analyzed at 3, 6 and 9 months postinfection (MPI). H. cinaedi colonized the cecum, colon, and stomach in infected mice. H. cinaedi induced typhlocolitis in Rag2(-/-) mice by 3 MPI and intestinal lesions