Ac-hE18A-NH is a dual-domain apoE mimetic peptide that possesses the putative receptor binding domain from apoE (LRKLRKRLLR, denoted hE; residues 141-150) covalently attached to lipid-associating peptide 18A. Like apoE, Ac-hE18A-NH reduces plasma cholesterol in animal models and exhibits anti-inflammatory properties independent of its cholesterol-reducing effect. Ac-hE18A-NH has already undergone phase I clinical trials as a lipid-lowering agent.
View Article and Find Full Text PDFCardiovascular disease, specifically atherosclerosis, is exacerbated by hypercholesterolemia. Current therapies that target lipid lowering, however, are not effective in all patients. Apolipoprotein E (apoE) plays an important role in mediating the clearance of plasma cholesterol and also exerts numerous cytoprotective responses.
View Article and Find Full Text PDFPurpose: Accumulation of lipoprotein-derived lipids including esterified and unesterified cholesterol in Bruch's membrane of human eyes is a major age-related change involved in initiating and sustaining soft drusen in age-related macular degeneration (AMD). The apolipoprotein (apo) A-I mimetic peptide 4F is a small anti-inflammatory and anti-atherogenic agent, and potent modifier of plasma membranes. We evaluated the effect of intravitreally-injected 4F on murine Bruch's membrane.
View Article and Find Full Text PDFApolipoprotein (apo)A-I and apoE are the two protein components that have been extensively investigated for their anti-atherogenic properties. Both apolipoproteins possess amphipathic helical structures, responsible for the solubilization of lipids. While apoA-I possesses class A amphipathic helical structures, apoE possesses a 59 residue long amphipathic helical domain linked to a four helix bundle containing the Arg-rich, 10 residue receptor binding domain.
View Article and Find Full Text PDFReduced levels of HDL cholesterol (HDL-C) are a strong independent predictor of coronary artery disease (CAD) risk. The major anti-atherogenic function of HDL is to mediate reverse cholesterol transport. This response is highly dependent on apoA-I and apoE, protein components of HDL.
View Article and Find Full Text PDFEndotoxemia is a major cause of chronic inflammation, and is an important pathogenic factor in the development of metabolic syndrome and atherosclerosis. Human apolipoprotein E (apoE) and apoA-I are protein components of high-density lipoprotein, which have strong anti-endotoxin activity. Here, we compared anti-endotoxin activity of Ac-hE18A-NH2 and 4F peptides, modified from model amphipathic helical 18A peptide, to mimic, respectively, apoE and apoA-I properties.
View Article and Find Full Text PDFHypercholesterolemia is a risk factor for the development of hypertrophic cardiomyopathy. Nevertheless, there are few studies aimed at determining the effects of dietary compounds on early or mild cardiac hypertrophy associated with dyslipidemia. Here we describe left ventricular (LV) hypertrophy in 12 week-old Apo E(-/-) hypercholesterolemic mice.
View Article and Find Full Text PDFThe cationic single domain peptide mR18L has demonstrated lipid-lowering and anti-atherogenic properties in different dyslipidemic mouse models. Lipopolysaccharide (LPS)-mediated inflammation is considered as one of the potential triggers for atherosclerosis. Here, we evaluated anti-inflammatory effects of mR18L peptide against LPS-mediated inflammation.
View Article and Find Full Text PDFBackground: Apolipoprotein E (ApoE) is the major apolipoprotein present in the high-density lipoprotein-like particles in the central nervous system (CNS). ApoE is involved in various protective functions in CNS including cholesterol transport, anti-inflammatory, and antioxidant effects. An ApoE peptide would be expected to exert protective effects on neuroinflammation.
View Article and Find Full Text PDFObjective: We investigated two apoE mimetic peptides with similar long-term plasma cholesterol reducing abilities for their effects on atherosclerotic lesions in Western diet-fed female LDL-receptor (LDL-R) null mice.
Methods And Results: Single doses of peptides Ac-hE18A-NH(2) and mR18L were administered retro-orbitally to LDL-R null mice on Western diet and plasma cholesterol was measured at 10 min, 4 h, and 24 h post administration. Peptide mR18L and not Ac-hE18A-NH(2) reduced plasma cholesterol levels significantly at 4 h post administration.
Objective: The apolipoprotein E mimetic peptide Ac-hE18A-NH(2), capable of reducing plasma cholesterol and possessing anti-inflammatory properties, was compared with the well-studied anti-atherogenic apoA-I mimetic peptide 4F for reducing lesion formation in female apoE null mice with already existing lesions.
Methods And Results: In initial experiments, Ac-hE18A-NH(2) was administered retro-orbitally two or three times weekly for 6-8 weeks, while peptide 4F was administered intraperitoneally every day for the same period. Age matched controls were injected with saline every day.
To test the hypothesis that sidedness of interfacial arginine (Arg) in apoA-I mimetic peptides, similar to that observed in apoA-I (Bashtovyy, D. et al. 2011.
View Article and Find Full Text PDFApolipoprotein E (apoE) is a ligand for clearance of lipoprotein remnants such as chylomicrons and very low-density lipoproteins. It has anti-atherogenic and anti-inflammatory properties. Therefore, there is extensive ongoing research to create peptides that can mimic properties of apoE.
View Article and Find Full Text PDFObjective: We recently described anti-atherogenic properties of the dual domain peptide Ac-hE18A-NH(2) derived by covalently linking the heparin binding domain 141-150 of apoE to 18A, a class A amphipathic helical peptide. In this paper we have compared the properties of Ac-hE18A-NH(2) with the non-heparin binding 151-160 region of apoE linked to 18A (Ac-nhE18A-NH(2)).
Methods And Results: Both peptides were highly helical in solution and in association with lipids.
We have shown that Ac-hE18A-NH₂, a dual-domain cationic apolipoprotein-mimetic peptide, reduces plasma cholesterol levels in dyslipidemic mice. Two single-domain cationic peptides based on the lytic class L peptide 18L were developed to test the hypothesis that a single-domain cationic amphipathic peptide can reduce atherosclerosis in apolipoprotein (apo)E null mice when orally administered. To incorporate anti-inflammatory properties, aromatic residues were clustered in the nonpolar face similar to peptide 4F, resulting in modified 18L (m18L).
View Article and Find Full Text PDFApoE mimetic peptide possesses the putative receptor binding domain 141-150 (LRKLRKRLLR) of apoE covalently linked to the class A amphipathic helical peptide 18A. It dramatically reduces plasma cholesterol in dyslipidemic mouse and rabbit models. Recycling of apoE mimetic peptide increases the duration of preβ-HDL formation leading to extended anti-inflammatory and atheroprotective properties.
View Article and Find Full Text PDFAnti-atherogenic effects of high density lipoprotein (HDL) and its major protein component apolipoprotein A-I (apoA-I) are principally thought to be due to their ability to mediate reverse cholesterol transport. These agents also possess anti-oxidant properties that prevent the oxidative modification of low density lipoprotein (LDL) and anti-inflammatory properties that include inhibition of endothelial cell adhesion molecule expression. Results of the Framingham study revealed that a reduction in HDL levels is an independent risk factor for coronary artery disease (CAD).
View Article and Find Full Text PDFApolipoprotein E (apoE) exerts prominent anti-inflammatory effects and undergoes recycling by target cells. We previously reported that the peptide Ac-hE18A-NH(2), composed of the receptor binding domain (LRKLRKRLLR) of apoE covalently linked to the Class A amphipathic peptide 18A, dramatically lowers plasma cholesterol and lipid hydroperoxides and enhances paraoxonase activity in dyslipidemic animal models. The objective of this study was to determine whether this peptide, analogous to apoE, exerts anti-inflammatory effects and undergoes recycling under in vitro conditions.
View Article and Find Full Text PDFRecent evidence indicates that inflammation may significantly contribute to the pathogenesis of Alzheimer's disease (AD). Since the apo A-I mimetic peptide D-4F has been shown to inhibit atherosclerotic lesion formation and regress already existing lesions (in the presence of pravastatin) and the peptide also decreases brain arteriole inflammation, we undertook a study to evaluate the efficacy of oral D-4F co-administered with pravastatin on cognitive function and amyloid beta (A beta) burden in the hippocampus of APPSwe-PS1 Delta E9 mice. Three groups of male mice were administered D-4F and pravastatin, Scrambled D-4F (ScD-4F, a control peptide) and pravastatin in drinking water, while drinking water alone served as control.
View Article and Find Full Text PDFCurr Atheroscler Rep
October 2008
3-Hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) are currently the drug of choice for the clinical management of elevated low-density lipoprotein (LDL) cholesterol. Although statin treatment provides an overall improvement in outcomes, clinical trial data reveal a significant number of cardiac events despite reaching targeted LDL levels. A low serum high-density lipoprotein (HDL) cholesterol level is an independent predictor of cardiovascular risk.
View Article and Find Full Text PDFRecently, attention has been focused on pharmacological treatments that increase HDL cholesterol to prevent coronary artery disease. Despite three decades of extensive research of human apolipoprotein A-I (apoA-I), the major protein component of HDL, the molecular basis for its antiatherogenic and anti-inflammatory functions remain elusive. Another protein component of HDL, apoA-II, has structural features similar to those of apoA-I but does not possess atheroprotective properties.
View Article and Find Full Text PDFTwo homologous apoA-I mimetic peptides, 3F-2 and 3F(14), differ in their in vitro antiatherogenic properties (Epand, R. M., Epand, R.
View Article and Find Full Text PDFLevels of high density lipoprotein (HDL) and its major protein component, apolipoprotein (apo) A-I, are strongly inversely correlated to risk of atherosclerosis and other vascular diseases. A number of properties of apo A-I may contribute to this protection, including removal of cholesterol from peripheral tissues to the liver (reverse cholesterol transport), anti-inflammatory and anti-oxidative activities, and modulation of vascular function. Apo A-I has lipid-associating domains that form class A amphipathic helices.
View Article and Find Full Text PDFPurpose Of Review: Recent publications related to the potential use of synthetic peptides for the management of lipid disorders and their vascular complications are reviewed.
Recent Findings: The potential use of synthetic peptides for the management of lipid disorders and their vascular complications has emerged in recent years. These peptides are models of apolipoproteins, but are much smaller in size than the apolipoproteins.
Cholesterol can promote inflammation by its ability to stimulate the production of reactive oxygen species that result in the formation of pro-inflammatory oxidised phospholipids. High-density lipoproteins (HDLs) are part of the innate immune response and can be either pro- or anti-inflammatory independently of plasma HDL-cholesterol levels. During systemic inflammation as occurs with atherosclerosis, Apolipoprotein A-I can be altered, reducing its ability to promote reverse cholesterol transport and HDL can become pro-inflammatory.
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