Subfractionation of Sf 4–105, Sf 4–20 and high density lipoproteins

Lindgren, Frank T.; Jensen, L. C.; Wills, R. D.; Stevens, G. R.

doi:10.1007/bf02533063

Cited by 34 publications

(6 citation statements)

References 22 publications

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“…Conditioned medium was concentrated 100-fold using a Minitan ultrafiltration system (Millipore Corp., Bedford, MA) fitted with a 10 000 MW cutoff cellulose membrane. Lipoprotein fractions, d < 1.063 g/mL and 1.063-1.21 g/mL ("nascent HDL"), were isolated from conditioned medium by sequential ultracentrifugation (16). Samples were dialyzed against saline/EDTA (0.15 mM NaCl, 2.7 mM EDTA), pH 7.4, for further analyses.…”

Section: Methodsmentioning

confidence: 99%

Deletion of Amino Acids Glu146→Arg160 in Human Apolipoprotein A-I (ApoA-I_Seattle) Alters Lecithin:Cholesterol Acyltransferase Activity and Recruitment of Cell Phospholipid

et al. 1998

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Human apolipoprotein A-I (apoA-I) has an important role in the efflux of cholesterol from peripheral cells, the first step in reverse cholesterol transport. Deletion of amino acids Glu146-->Arg160 in apoA-I (apoA-ISeattle) removes a large section of a lipid binding helix and is associated in vivo with an atherogenic lipoprotein profile characterized by a deficiency in high-density lipoproteins (HDL). In the present study, we asked whether apoA-ISeattle had normal ability to recruit lipids from cells and to form nascent high-density lipoprotein (HDL) particles and whether the altered secondary structure affected lecithin:cholesterol acyltransferase (LCAT) activity. Wild-type apoA-I and apoA-ISeattle expressed in transfected Chinese hamster ovary cells formed nascent HDL particles with similar density distribution and protein-to-lipid ratio. Phospholipid subclass distribution of apoA-ISeattle nascent HDL demonstrated a significant increase in sphingomyelin and phosphatidylethanolamine compared to wild type. ApoA-ISeattle nascent HDL had a unique size distribution compared to wild-type nascent HDL; large (9-20 nm) particles predominated while there were virtually no small (7.5 nm) particles. LCAT reactivity was impaired by apoA-ISeattle nascent HDL where cholesterol esterification was only half that of wild-type complexes. The apoA-ISeattle conformation on nascent HDL was studied with a panel of monoclonal antibodies (Mabs) specific for apoA-I. Mabs that recognize the putative LCAT activation site, residues 95-122, had normal reactivity. As expected, the Mabs that recognized residues 141-164 were unreactive because of the 146-160 deletion; in addition, there was low reactivity with a Mab that recognizes residues 220-242. The data suggest that apoA-I residues 146-160 and/or 220-242 partake in normal LCAT activation and that cooperative interactions between helices may be important for maximal cholesterol esterification.

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Section: Methodsmentioning

confidence: 99%

Deletion of Amino Acids Glu146→Arg160 in Human Apolipoprotein A-I (ApoA-I_Seattle) Alters Lecithin:Cholesterol Acyltransferase Activity and Recruitment of Cell Phospholipid

et al. 1998

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“…Currently, the separation of intestinal CMs and VLDLs is based on operational criteria. Lipoproteins that have a Svedberg flotation (S f ) rate exceeding 400 are classified as CMs; those with a S f rate of 20-400 are defined as VLDLs [63]. Numerous studies support the idea that intestinal CMs and VLDLs represent lipoprotein produced by two separate pathways.…”

Section: Formation Of Intestinal Chylomicrons and Very Low-density LImentioning

confidence: 99%

Cholesterol: from feeding to gene regulation

Martini

Pallottini

2007

Genes Nutr

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We present here a brief description of the path that cholesterol covers from its intestinal absorption to its effects exerted on gene regulation. In particular, the relationship between cholesterol and the protein complexes involved in the intricate gene regulation mechanism implicated in cholesterol homeostasis will be discussed. In addition, a new target role for the pharmacological interventions of one of these factors, the insulin-induced gene (Insig) protein, will be introduced.

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“…In addition we re-analyzed samples from a previous study of ANGPTL4 in patients on chronic hemodialysis (CHD) [25]. Pooled normal human serum was used for isolation of very low density lipoproteins (VLDL) by ultracentrifugation [26]. …”

Section: Methodsmentioning

confidence: 99%

High Concentrations of Angiopoietin-Like Protein 4 Detected in Serum from Patients with Rheumatoid Arthritis Can Be Explained by Non-Specific Antibody Reactivity

et al. 2017

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Angiopoietin-like protein 4 (ANGPTL4) is suggested to be a master regulator of plasma triglyceride metabolism. Our aim was to study whether the previously reported high levels of ANGPTL4 detected in serum from patients with rheumatoid arthritis (RA) by ELISA was due to any specific molecular form of this protein (oligomers, monomers or fragments). ANGPTL4 levels were first determined in serum from 68 RA patients and 43 age and sex matched control subjects and the mean values differed by a factor of 5.0. Then, ANGPTL4 was analyzed after size exclusion chromatography (SEC) of serum samples. With serum from one of the RA patients with high levels of ANGPTL4, the dominant reactivity was found in fractions corresponding to high-molecular weight proteins. In addition, a minor peak of reactivity eluting late from the column was found both in the patient and in controls. By the use of HeteroBlock®, and by careful selection of antibodies, we documented non-specific reactions for ANGPTL4 in 39% of samples from the RA patients, most likely due to cross-reactivity of the antibodies with rheumatoid factor (RF). The corresponding figure for control subjects was 6.3%. After corrections for non-specific reactions, the mean level of ANGPTL4 in serum from RA patients was still significantly higher than in control individuals (mean levels were 101±62 and 67±39 ng/ml respectively, P = 0.02). We re-analyzed samples from our previously published studies on ANGPL4 levels in patients on hemodialysis and patients with diabetes type 2. These samples did not show false positive reactions. The levels of ANGPTL4 were comparable to those detected previously.

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Subfractionation of S_f 4–10⁵, S_f 4–20 and high density lipoproteins

Cited by 34 publications

References 22 publications

Deletion of Amino Acids Glu146→Arg160 in Human Apolipoprotein A-I (ApoA-I_Seattle) Alters Lecithin:Cholesterol Acyltransferase Activity and Recruitment of Cell Phospholipid

Deletion of Amino Acids Glu146→Arg160 in Human Apolipoprotein A-I (ApoA-I_Seattle) Alters Lecithin:Cholesterol Acyltransferase Activity and Recruitment of Cell Phospholipid

Cholesterol: from feeding to gene regulation

High Concentrations of Angiopoietin-Like Protein 4 Detected in Serum from Patients with Rheumatoid Arthritis Can Be Explained by Non-Specific Antibody Reactivity

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Subfractionation of Sf 4–105, Sf 4–20 and high density lipoproteins

Cited by 34 publications

References 22 publications

Deletion of Amino Acids Glu146→Arg160 in Human Apolipoprotein A-I (ApoA-ISeattle) Alters Lecithin:Cholesterol Acyltransferase Activity and Recruitment of Cell Phospholipid

Deletion of Amino Acids Glu146→Arg160 in Human Apolipoprotein A-I (ApoA-ISeattle) Alters Lecithin:Cholesterol Acyltransferase Activity and Recruitment of Cell Phospholipid

Cholesterol: from feeding to gene regulation

High Concentrations of Angiopoietin-Like Protein 4 Detected in Serum from Patients with Rheumatoid Arthritis Can Be Explained by Non-Specific Antibody Reactivity

Contact Info

Product

Resources

About

Subfractionation of S_f 4–10⁵, S_f 4–20 and high density lipoproteins

Deletion of Amino Acids Glu146→Arg160 in Human Apolipoprotein A-I (ApoA-I_Seattle) Alters Lecithin:Cholesterol Acyltransferase Activity and Recruitment of Cell Phospholipid

Deletion of Amino Acids Glu146→Arg160 in Human Apolipoprotein A-I (ApoA-I_Seattle) Alters Lecithin:Cholesterol Acyltransferase Activity and Recruitment of Cell Phospholipid