Millipore Sigma Vibrant Logo
 

apolipoproetin+c-iii


74 Results Gelişmiş Arama  
Showing
Dokümanlar (70)
Site Content (0)

Sonuçlarınızı Daraltın Use the filters below to refine your search

Aradığınızı Bulamadınız mı?
Müşteri Hizmetleri ile
İletişime Geçin

 
MilliporeSigma Documents

Doküman ararken yardıma ihtiyacınız var mı?

  • Analiz sertifikaları, Kalite Sertifikaları veya Güvenlik Bilgi Formlarını aramak için Doküman Arayıcı’yı kullanmayı deneyin.
     
  • Kullanım Kılavuzlarına erişmek için yardıma ihtiyacınız olur ise Müşteri Hizmetleri ile iletişime geçebilirsiniz.
  • Differential interaction of Apolipoprotein-E isoforms with insulin receptors modulates brain insulin signaling in mutant human amyloid precursor protein transgenic mice. 26346625

    It is unclear how human apolipoprotein E4 (ApoE4) increases the risk for Alzheimer's disease (AD). Although Aβ levels can lead to insulin signaling impairment, these experiments were done in the absence of human ApoE. To examine ApoE role, we crossed the human ApoE-targeted replacement mice with mutant human amyloid precursor protein (APP) mice. In 26 week old mice with lower Aβ levels, the expression and phosphorylation of insulin signaling proteins remained comparable among APP, ApoE3xAPP and ApoE4xAPP mouse brains. When the mice aged to 78 weeks, these proteins were markedly reduced in APP and ApoE4xAPP mouse brains. While Aβ can bind to insulin receptor, how ApoE isoforms modulate this interaction remains unknown. Here, we showed that ApoE3 had greater association with insulin receptor as compared to ApoE4, regardless of Aβ42 concentration. In contrast, ApoE4 bound more Aβ42 with increasing peptide levels. Using primary hippocampal neurons, we showed that ApoE3 and ApoE4 neurons are equally sensitive to physiological levels of insulin. However, in the presence of Aβ42, insulin failed to elicit a downstream response only in ApoE4 hippocampal neurons. Taken together, our data show that ApoE genotypes can modulate this Aβ-mediated insulin signaling impairment.
    Document Type:
    Reference
    Product Catalog Number:
    09-432
    Product Catalog Name:
    Anti-phospho-IRS1 (Tyr608) mouse/ (Tyr612) human Antibody
  • Discrimination of grade 2 and 3 cervical intraepithelial neoplasia by means of analysis of water soluble proteins recovered from cervical biopsies. 21711556

    BACKGROUND:
    Cervical intraepithelial neoplasia (CIN) grades 2 and 3 are usually grouped and treated in the same way as "high grade", in spite of their different risk to cancer progression and spontaneous regression rates. CIN2-3 is usually diagnosed in formaldehyde-fixed paraffin embedded (FFPE) punch biopsies. This procedure virtually eliminates the availability of water-soluble proteins which could have diagnostic and prognostic value.

    AIM:
    To investigate whether a water-soluble protein-saving biopsy processing method followed by a proteomic analysis of supernatant samples using LC-MS/MS (LTQ Orbitrap) can be used to distinguish between CIN2 and CIN3.

    METHODS:
    Fresh cervical punch biopsies from 20 women were incubated in RPMI1640 medium for 24 hours at 4°C for protein extraction and subsequently subjected to standard FFPE processing. P16 and Ki67-supported histologic consensus review CIN grade (CIN2, n = 10, CIN3, n = 10) was assessed by independent gynecological pathologists. The biopsy supernatants were depleted of 7 high abundance proteins prior to uni-dimensional LC-MS/MS analysis for protein identifications.

    RESULTS:
    The age of the patients ranged from 25-40 years (median 29.7), and mean protein concentration was 0.81 mg/ml (range 0.55 - 1.14). After application of multistep identification criteria, 114 proteins were identified, including proteins like vimentin, actin, transthyretin, apolipoprotein A-1, Heat Shock protein beta 1, vitamin D binding protein and different cytokeratins. The identified proteins are annotated to metabolic processes (36%), signal transduction (27%), cell cycle processes (15%) and trafficking/transport (9%). Using binary logistic regression, Cytokeratin 2 was found to have the strongest independent discriminatory power resulting in 90% overall correct classification.

    CONCLUSIONS:
    114 proteins were identified in supernatants from fresh cervical biopsies and many differed between CIN2 and 3. Cytokeratin 2 is the strongest discriminator with 90% overall correct classifications.
    Document Type:
    Reference
    Product Catalog Number:
    07-330
    Product Catalog Name:
    Anti-Partitioning-defective 3 Antibody
  • Overexpression of apolipoprotein A5 in mice is not protective against body weight gain and aberrant glucose homeostasis. 19303979

    Apolipoprotein A5 (APOA5) is expressed primarily in the liver and modulates plasma triglyceride levels in mice and humans. Mice overexpressing APOA5 exhibit reduced plasma triglyceride levels. Because there is a tight association between plasma triglyceride concentration and traits of the metabolic syndrome, we used transgenic mice overexpressing human APOA5 to test the concept that these mice would be protected from diet-induced obesity and insulin resistance. Male and female transgenic and wild-type mice on the FVB/N genetic background were fed standard rodent chow or a diet rich in fat and sucrose for 18 weeks, during which time clinical phenotypes associated with obesity and glucose homeostasis were measured. We found that APOA5 transgenic (A5tg) mice were resistant to diet-induced changes in plasma triglyceride but not total cholesterol levels. Body weights were similar between the genotypes for females and males, although male A5tg mice showed a modest but significant increase in the relative size of inguinal fat pads. Although male A5tg mice showed a significantly increased ratio of plasma glucose to insulin, profiles of glucose clearance as evaluated after injections of glucose or insulin failed to reveal any differences between genotypes. Overall, our data showed that there was no advantage to responses to diet-induced obesity with chronic reduction of plasma triglyceride levels as mediated by overexpression of APOA5.
    Document Type:
    Reference
    Product Catalog Number:
    EZRMI-13K
    Product Catalog Name:
    Rat/Mouse Insulin ELISA
  • Opposite roles of apolipoprotein E in normal brains and in Alzheimer's disease. 9861015

    We have characterized the interaction between apolipoprotein E (apoE) and amyloid beta peptide (Abeta) in the soluble fraction of the cerebral cortex of Alzheimer's disease (AD) and control subjects. Western blot analysis with specific antibodies identified in both groups a complex composed of the full-length apoE and Abeta peptides ending at residues 40 and 42. The apoE-Abeta soluble aggregate is less stable in AD brains than in controls, when treated with the anionic detergent SDS. The complex is present in significantly higher quantity in control than in AD brains, whereas in the insoluble fraction an inverse correlation has previously been reported. Moreover, in the AD subjects the Abeta bound to apoE is more sensitive to protease digestion than is the unbound Abeta. Taken together, our results indicate that in normal brains apoE efficiently binds and sequesters Abeta, preventing its aggregation. In AD, the impaired apoE-Abeta binding leads to the critical accumulation of Abeta, facilitating plaque formation.
    Document Type:
    Reference
    Product Catalog Number:
    AB947
    Product Catalog Name:
    Anti-Apolipoprotein E Antibody
  • Mechanism underlying apolipoprotein E (ApoE) isoform-dependent lipid efflux from neural cells in culture. 19326444

    We determined the molecular mechanisms underlying apolipoprotein E (ApoE)-isoform-dependent lipid efflux from neurons and ApoE-deficient astrocytes in culture. The ability of ApoE3 to induce lipid efflux was 2.5- to 3.9-fold greater than ApoE4. To explore the contributions of the amino- and carboxyl-terminal tertiary structure domains of ApoE to cellular lipid efflux, each domain was studied separately. The amino-terminal fragment of ApoE3 (22-kDa-ApoE3) induced lipid efflux greater than 22-kDa-ApoE4, whereas the common carboxyl-terminal fragment of ApoE induced very low levels of lipid efflux. Addition of segments of the carboxyl-terminal domain to 22-kDa-ApoE3 additively induced lipid efflux in a length-dependent manner; in contrast, this effect did not occur with ApoE4. This observation, coupled with the fact that introduction of the E255A mutation (which disrupts domain-domain interaction) into ApoE4 increases lipid efflux, indicates that interaction between the amino- and carboxyl-terminal domains in ApoE4 reduces the ability of this isoform to mediate lipid efflux from neural cells. Dimeric 22-kDa or intact ApoE3 induced higher lipid efflux than monomeric 22-kDa or intact ApoE3, respectively, indicating that dimerization of ApoE3 enhances the ability to release lipids. The adenosine triphosphate-binding cassette protein A1 (ABCA1) is involved in ApoE-induced lipid efflux. In conclusion, there are two major factors, intramolecular domain interaction and intermolecular dimerization, that cause ApoE-isoform-dependent lipid efflux from neural cells in culture.
    Document Type:
    Reference
    Product Catalog Number:
    AB947
    Product Catalog Name:
    Anti-Apolipoprotein E Antibody
  • Effect of intermittent hypoxia on atherosclerosis in apolipoprotein E-deficient mice. 19897196

    Obstructive sleep apnea causes intermittent hypoxia (IH) and is associated with increased cardiovascular mortality. This increased risk may be attributable to more extensive or unstable atherosclerotic plaques in subjects with OSA. We studied the effect of chronic IH in atherosclerosis-prone mice.Apolipoprotein E-deficient (ApoE(-/-)) mice fed a high cholesterol diet were exposed to 4 or 12 weeks of IH and compared to intermittent air-exposed controls. At 4 weeks, IH increased plaque size in the aortic sinus and the descending aorta. At 12 weeks, atherosclerosis progressed in all groups, but more rapidly in the descending aorta of IH-exposed animals. Plaque composition was similar between IH and controls. Between 4 and 12 weeks, there were progressive increases in blood pressure, with relatively stable increases in serum lipids and arterial stiffness.IH accelerates atherosclerotic plaque growth in ApoE(-/-) mice without affecting plaque composition. The mechanisms may include non-additive increases in serum lipids, and cumulative increases in blood pressure.
    Document Type:
    Reference
    Product Catalog Number:
    AB5411
    Product Catalog Name:
    Anti-Nitrotyrosine Antibody
  • Homocysteine, another risk factor for Alzheimer disease, impairs apolipoprotein E3 function. 20889503

    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.
    Document Type:
    Reference
    Product Catalog Number:
    AB947
    Product Catalog Name:
    Anti-Apolipoprotein E Antibody
  • Partnership of PGC-1alpha and HNF4alpha in the regulation of lipoprotein metabolism. 16574644

    Peroxisome proliferator-activated receptor gamma coactivator-1alpha (PGC-1alpha) is a transcriptional coactivator involved in several aspects of energy metabolism. It is induced or activated under different stimuli in a highly tissue-specific manner and subsequently partners with certain transcription factors in those tissues to execute various biological programs. In the fasted liver, PGC-1alpha is induced and interacts with hepatocyte nuclear factor 4alpha (HNF4alpha) and other transcription factors to activate gluconeogenesis and increase hepatic glucose output. Given the broad spectrum of liver genes responsive to HNF4alpha, we sought to determine those that were specifically targeted by the combination of PGC-1alpha and HNF4alpha. Coexpression of these two molecules in murine stem cells reveals a high induction of mRNA for apolipoproteins A-IV and C-II. Forced expression of PGC-1alpha in mouse and human hepatoma cells increases the mRNA of a subset of apolipoproteins implicated in very low density lipoprotein and triglyceride metabolism, including apolipoproteins A-IV, C-II, and C-III. Coactivation of the apoC-III/A-IV promoter region by PGC-1alpha occurs through a highly conserved HNF4alpha response element, the loss of which completely abolishes activation by PGC-1alpha and HNF4alpha. Adenoviral infusion of PGC-1alpha into live mice increases hepatic expression of apolipoproteins A-IV, C-II, and C-III and increases serum and very low density lipoprotein triglyceride levels. Conversely, knock down of PGC-1alpha in vivo causes a decrease in both apolipoprotein expression and serum triglyceride levels. These data point to a crucial role for the PGC-1alpha/HNF4alpha partnership in hepatic lipoprotein metabolism.
    Document Type:
    Reference
    Product Catalog Number:
    17-371
    Product Catalog Name:
    EZ-ChIP™
  • Lipoprotein profiles in SCID/uPA mice transplanted with human hepatocytes become human-like and correlate with HCV infection success. 20651006

    Although multiple determinants for hepatitis C virus (HCV) infection are known, it remains partly unclear what determines the human specificity of HCV infection. Presumably, the presence of appropriate entry receptors is essential, and this may explain why HCV is unable to infect nonhuman hepatocytes. However, using mice with chimeric human livers, we show in this study that the presence of human hepatocytes, and therefore human entry receptors, is not sufficient for HCV infection. In successfully transplanted SCID/Alb-uPA mice, infection with HCV is reliable only when ∼70-80% of the liver consists of human hepatocytes. We show that chimeric mice, which are hard to infect with HCV, have significant groups of human hepatocytes that are readily infected with hepatitis B virus. Thus it is unlikely that the lack of infection with HCV can simply be attributed to low hepatocyte numbers. We investigated whether the humanization of lipoprotein profiles is positively associated with infection success. We show that the lipoprotein profiles of chimeric mice become more human-like at high levels of engraftment of human hepatocytes. This and expression of markers of human lipoprotein biosynthesis, human apolipoprotein B (ApoB) and cholesterol ester transfer protein (CETP), show a strong positive correlation with successful infection. Association of HCV in the blood of chimeric mice to ApoB-containing lipoproteins is comparable to association of HCV in patient serum and provides further support for a critical role for ApoB-containing lipoproteins in the infectious cycle of HCV. Our data suggest that the weakest link in the HCV infection chain does not appear to be the presence of human hepatocytes per se. We believe that HCV infection also depends on the presence of sufficient levels of human lipoproteins.
    Document Type:
    Reference
    Product Catalog Number:
    AB742
    Product Catalog Name:
    Anti-Apolipoprotein B Antibody