Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0004153 (atherosclerosis)
 77,401 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Recent evidence from a double-blind, randomized study showed that treatment with apolipoprotein A-I Milano (ApoA-I Milano) in a complex with phospholipids produced significant regression of the coronary atheroma burden in patients with acute coronary syndromes. We previously showed similar regression of atherosclerosis in an animal model. Here, we examined a viral vector-based gene delivery system as a basis for ApoA-I Milano gene therapy. Comparing levels of expression using combinations of the cytomegalovirus (CMV) promoter in a recombinant serotype 2 adeno-associated virus (rAAV2) linked to ApoA-I Milano or the enhanced green fluorescent protein (EGFP) genes, we found that a promoter construct of two CMV core promoters sharing a CMV enhancer was more active than other combinations or a single CMV promoter. In vivo assessment of this optimal CMV construct using rAAV2 virus particles for intravenous (IV) or intramuscular (IM) routes of delivery produced high circulating levels of ApoA-I Milano protein for extended periods (up to 220 ng/ml at 22 weeks p.i.) by IV delivery while the IM route resulted in a relatively short period of very low-level ApoA-I Milano expression. Since there was no difference in the immune response between the two routes of delivery, we reasoned that tissue tropism might be responsible for this differential gene expression. To explore this possibility, we investigated the effect of different AAV serotypes on ApoA-I Milano gene expression in vivo. It found that rAAV1-mediated expression of ApoA-I Milano was approximately 15- and 9-fold higher than rAAV2 and rAAV5, respectively when IM injection routes were compared while all three AAV serotypes produced substantial levels of ApoA-I Milano expression from IV injection. These studies demonstrate that by modifying the promoter and serotype, increases in the efficiency of AAV-directed transgene expression could be achieved and support the potential of AAV-mediated gene therapy.
Atherosclerosis 2005 Aug
PMID:AAV serotype-dependent apolipoprotein A-I Milano gene expression. 1603 79

The prevention of atherosclerosis depends on the high-density lipoprotein (HDL) capacity to stimulate the efflux of unesterified cholesterol (UC). We tested here the effects of 2 HDL apolipoproteins, apo A-I and the 7-kd anionic peptide factor (APF), on the UC efflux by human endothelial ECV 304 cells in culture. Apolipoprotein A-I (10 micromol/L) or APF (3.5 micromol/L) in lipid-free forms or small particles (13 nm with apo A-I or 19 nm with APF) were incubated in the presence of [4-14C]UC. The phosphatidylcholines (PCs) were present either at a low level (0.35 mmol/L with apo A-I or 0.20 mmol/L with APF) or at a high level (1 mmol/L with apo A-I). We also tested either large 53-nm bile lipoprotein complex-like particles (3.5 micromol/L APF [13 microg/500 microL]) with a high PC level (0.65 mmol/L) or a 9-residue synthetic peptide (13 microg/500 microL), derived from the NH2-terminal domain of HDL3-APF, in a lipid-free or low-lipidated (0.20 mmol/L PCs) form. A control was developed in absence of the added compounds. A rapid [4-14C]UC efflux mediated by APF added in free form or in 19-nm complexes was 2.2- to 2.3-fold higher than that mediated by apo A-I in free form or in 13-nm particles (P < .05). The level of this high APF-related efflux was comparable with that obtained with the 12-nm native HDLs (10 micromol/L apo A-I) or free PCs (1 mmol/L). The increase in the UC efflux was much more limited (1.4-fold) in the presence of the 53-nm APF/high-PC particles, but it was higher than that mediated by apo A-I. In addition, the efflux mediated by the synthetic peptide, in lipid-free or low-lipidated form, constituted the major part of that related to the full-length APF. Thus, all these particles are very active HDL components, able to act as cholesterol acceptors. Interestingly, we further showed a new anti-atherogenic property of APF as well as its metabolic importance and clinical relevance. By its involvement in the first step of the reverse cholesterol transport, APF could reduce the risk of cardiovascular disease.
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PMID:The endothelial cholesterol efflux is promoted by the high-density lipoprotein anionic peptide factor. 1609 60

Apolipoprotein A-I-Milano(AIM), a natural variant, not only inhibits the initiation and progression of atherosclerosis, but also makes the preexisting atherosclerotic lesions regress. AIM gene, at which N-terminal codens were optimized, was subcloned into the expression vector of pET22b. Recombiant plasmids were transformed into E. coli strain BL21 (DE3) and induced with IPTG. The expressed apoliprotein A-I-Milano was soluble in E. coli and was about 38% of total cell lysate. Purified by Butyl Sepharose 4F. F hydrophobic chromatography and Q Sepharose H.P. anion exchange chromatography, followed by ultrafiltration with Vivaspin 20 (30 000MW), AIM monomer was obtained in a purity of more than 95%. Activity assay of binding of AIM monomer to lipid indicates that association of AIM monomer with DMPC is slower than normal apoA-I but DMPC number associated by AIM monomer is more than by apoA-I. This results will be important for studying structure, function of AIM, specially clinical application.
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PMID:[Soluble expression of recombinant human apoliprotein A-I-Milano in Escherichia coli]. 1610 55

To test the hypothesis that apolipoprotein A-I (apoA-I) functions specifically to inhibit atherosclerosis independent of the level of high-density lipoprotein cholesterol (HDL-C) by promoting both reverse cholesterol transport and HDL antiinflammatory function in vivo, we established a murine atherosclerosis model of apoA-I deficiency in which the level of HDL-C is well maintained. ApoA-I-/- mice were crossed with atherosclerosis susceptible low-density lipoprotein receptor-/-/apobec-/- (LA) mice to generate LA mice with apoA-I+/+, apoA-I+/-, and apoA-I-/- genotypes. There were no major differences in the amounts of non-HDL-C and HDL-C in the plasma between different apoA-I genotypes. A significant inverse relationship was observed, however, between apoA-I gene dose and atherosclerosis in both female and male mice. Compared with LA-apoA-I+/+ mice, serum from LA-apoA-I-/- mice had a significantly reduced capacity to function as an acceptor of ABCA1- and SR-BI-mediated cellular cholesterol efflux, and also had markedly reduced lecithin cholesterol acyltransferase activity. In addition, LA-apoA-I-/- mice had significantly reduced macrophage-derived cholesterol esterification and reverse cholesterol transport in vivo. There was significantly reduced plasma paraoxonase (PON-1) activity, impaired HDL vascular antiinflammatory function, and increased basal levels of monocyte chemotactic protein-1 in the plasma of LA-apoA-I-/- mice compared with LA-apoA-I+/+ mice. In LA-apoA-I-/- mice, there was also greater induction of some, but not all, inflammatory cytokines and chemokines in response to intraperitoneal injection of lipopolysaccharide than in LA-apoA-I+/+ mice. We conclude that apoA-I inhibits atherosclerosis by promoting both macrophage reverse cholesterol transport and HDL antiinflammatory function, and that these anti-atherogenic functions of apoA-I are largely independent of the plasma level of HDL-C in this mouse model.
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PMID:Increased atherosclerosis in mice lacking apolipoprotein A-I attributable to both impaired reverse cholesterol transport and increased inflammation. 1615 Oct 25

Apolipoprotein A-I (apoA-I), the major protein component of serum high-density lipoprotein, exhibits anti-inflammatory activity in atherosclerosis. In this study, we demonstrate that apoA-I inhibits DC differentiation and maturation. DC differentiated from monocytes in the presence of apoA-I showed a decreased expression of surface molecules such as CD1a, CD80, CD86, and HLA-DR. In addition, these DC exhibited decreased endocytic activity and weakened allogeneic T-cell activation. During DC differentiation in the presence of apoA-I, PGE(2) and IL-10, which are known to be DC differentiation inhibitors and/or modulators of DC function, were produced at remarkable rates, whereas IL-12 production in the cells after stimulation with CD40 mAb and IFN-gamma was significantly decreased in comparison with the control DC. T cells stimulated by apoA-I-pretreated DC produced significantly low levels of IFN-gamma, and apoA-I inhibited cross-talk between DC and NK cells, in terms of IL-12 and IFN-gamma production. Therefore, apoA-I appears to play an important role in modulating both innate immune response and inflammatory response. The novel inhibitory function of apoA-I on DC differentiation and function may facilitate the development of new therapeutic interventions in inflammatory diseases.
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PMID:Apolipoprotein A-I induces IL-10 and PGE2 production in human monocytes and inhibits dendritic cell differentiation and maturation. 1625 56

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. Amphipathic peptides with either a class A amphipathic helix (D-4F) or a class G* amphipathic helix (D-[113-122]apoJ), or even those that are too small to form a helix (KRES and FREL) have some similar characteristics. Their interaction with lipids leads to a reduction in lipoprotein-lipid hydroperoxides that releases HDL-associated antioxidant enzymes, such as paraoxonase, therefore providing antiatherosclerosis and anti-inflammatory activity. In addition, the peptide D-4F stimulates the formation and cycling of pre-beta HDL. These amphipathic peptides appear to have therapeutic potential as oral agents.
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PMID:Oral amphipathic peptides as therapeutic agents. 1637 Sep 30

Hyperhomocysteinemia, a risk factor for cardiovascular disease, is caused by nutritional or genetic disturbances in homocysteine metabolism. A polymorphism in methylenetetrahydrofolate reductase (MTHFR) is the most common genetic cause of mild hyperhomocysteinemia. To examine mechanisms by which an elevation in plasma homocysteine leads to vascular disease, we first performed microarray analyses in livers of Mthfr-deficient mice and identified differentially expressed genes that are involved in lipid and cholesterol metabolism. Microarrays and RT-PCR showed decreased mRNA for apolipoprotein A (ApoA)-IV and for ApoA-I and increased mRNA for cholesterol 7alpha hydroxylase (Cyp7A1) in Mthfr(+/-) mice compared with Mthfr(+/+) mice. Western blotting revealed that ApoA-I protein levels in liver and plasma of Mthfr(+/-) mice were 52% and 62% of levels in the respective tissues of Mthfr(+/+) mice. We also performed Western analysis for plasma ApoA-I protein levels in 60 males with coronary artery disease and identified a significant (P<0.01) negative correlation (-0.33) between ApoA-I and plasma homocysteine levels. This cohort also displayed a negative correlation (-0.24, P=0.06) between high-density lipoprotein cholesterol and plasma homocysteine. Treatment of HepG2 cells with supraphysiological levels of 5 mmol/L homocysteine reduced peroxisome proliferator-activated receptor (PPAR) alpha and ApoA-I protein levels and decreased ApoA-I promoter activity. Transfection with a PPARalpha construct upregulated ApoA-I and MTHFR. Our results suggest that hyperhomocysteinemia may increase risk of atherosclerosis by decreasing expression of ApoA-I and increasing expression of CYP7A1.
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PMID:Elevated homocysteine reduces apolipoprotein A-I expression in hyperhomocysteinemic mice and in males with coronary artery disease. 1651 70

Apolipoprotein A-I(Milano) (apoA-I(M)) is a natural variant of apoA-I characterized by a cysteine for arginine substitution at position 173 of the primary sequence. ApoA-I(M) carriers have much less atherosclerosis than expected from their very low plasma high-density lipoprotein (HDL) cholesterol levels, suggesting that the variant might be protective. Synthetic HDL (sHDL) made with a recombinant form of the dimeric A-I(M) (A-I(M)/A-I(M)) and phospholipids given in single or multiple injections is effective in inducing the regression of atherosclerotic plaques, preventing arterial restenosis, and limiting cardiac dysfunction after ischemia/reperfusion injury. In a phase II trial in patients with acute coronary syndromes, a short-term treatment with A-I(M)/A-I(M) sHDL caused a remarkable reduction of atheroma burden. Although at early stages of drug development, A-I(M)/A-I(M) sHDL holds vast promise for the treatment of a variety of cardiovascular diseases in humans.
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PMID:Recombinant apolipoprotein A-IMilano for the treatment of cardiovascular diseases. 1651 51

Epidemiological data suggest a link between chronic inflammation condition and atherosclerosis. Infection and inflammation can also impair lipoprotein metabolism and produce a wide variety of changes in plasma concentrations of lipids and lipoproteins. Twenty-one patients with inflammatory bowel diseases (IBDs) and 28 healthy subjects were recruited. Serum concentrations of lipids, lipoproteins, apolipoproteins, leptin, ghrelin, and inflammation markers (C-reactive protein and serum amyloid A) were measured, and subjects' lipoproteins were characterized. The ability of patients with serum IBD to efflux free cell cholesterol was measured. Serum cholesterol, high-density lipoprotein cholesterol, apolipoprotein (apo) A-I, apoC-II, apoC-III bound to apoB, phospholipid, and phospholipids not bound to apoB levels were significantly lower, whereas serum triglyceride, serum amyloid A, and C-reactive protein levels were significantly higher in patients with active IBD. Apolipoprotein A-I immunoreactivity (pre-beta small particles and small alpha-high-density lipoprotein particles) is decreased in patients with IBD. In contrast, apoE immunoreactivity (slow/small apoE containing lipoprotein particles [LpE particle]) increased in these patients. The efflux capacity of serum from patients with IBD using [(3)H]-cholesterol-labeled Fu5AH cells was reduced (P < .005). Our results demonstrate that, in subjects with active IBD, inflammation leads to alterations in lipid, apolipoprotein, and lipoprotein profiles and reduced cholesterol efflux. These changes are similar to those proposed to promote atherogenesis and may contribute to the development of cardiovascular events.
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PMID:Altered lipid, apolipoprotein, and lipoprotein profiles in inflammatory bowel disease: consequences on the cholesterol efflux capacity of serum using Fu5AH cell system. 1678 73

We previously reported that hyperhomocysteinemia (HHcy), an independent risk factor of coronary artery disease (CAD), is associated with increased atherosclerosis and decreased plasma high-density lipoprotein cholesterol (HDL-C) in cystathionine beta-synthase-/apolipoprotein E-deficient (CBS(-/-)/apoE(-/-)) mice. We observed that plasma homocysteine (Hcy) concentrations are negatively correlated with HDL-C and apolipoprotein A1 (apoA-I) in patients with CAD. We found the loss of large HDL particles, increased HDL-free cholesterol, and decreased HDL protein in CBS(-/-)/apoE(-/-) mice, and attenuated cholesterol efflux from cholesterol-loaded macrophages to plasma in CBS(-/-)/apoE(-/-) mice. ApoA-I protein was reduced in the plasma and liver, but hepatic apoA-I mRNA was unchanged in CBS(-/-)/apoE(-/-) mice. Moreover, Hcy (0.5 to 2 mmol/L) reduced the levels of apoA-I protein but not mRNA and inhibited apoA-1 protein synthesis in mouse primary hepatocytes. Further, plasma lecithin:cholesterol acyltransferase (LCAT) substrate reactivity was decreased, LCAT specific activity increased, and plasma LCAT protein levels unchanged in apoE(-/-)/CBS(-/-) mice. Finally, the clearance of plasma HDL cholesteryl ester, but not HDL protein, was faster in CBS(-/-)/apoE(-/-) mice, correlated with increased scavenger receptor B1, and unchanged ATP-binding cassette transporter A1 protein expression in the liver. These findings indicate that HHcy inhibits reverse cholesterol transport by reducing circulating HDL via inhibiting apoA-I protein synthesis and enhancing HDL-C clearance.
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PMID:Hyperhomocysteinemia decreases circulating high-density lipoprotein by inhibiting apolipoprotein A-I Protein synthesis and enhancing HDL cholesterol clearance. 1697 11


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