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Novel Apo E-Derived ABCA1 Agonist Peptide (CS-6253) Promotes Reverse Cholesterol Transport and Induces Formation of preβ-1 HDL In Vitro.

Hafiane A, Bielicki JK, Johansson JO, Genest J - PLoS ONE (2015)

Bottom Line: We have previously reported the effects of compound ATI-5261 on its ability to replicate many functions of native apo A-I in the process of HDL biogenesis.CS-6253 significantly increases cholesterol efflux in murine macrophages and in human THP-1 macrophage-derived foam cells expressing ABCA1.When incubated with human plasma CS-6253 was also found to bind with HDL and LDL and promoted the transfer of cholesterol from HDL to LDL predominantly.

View Article: PubMed Central - PubMed

Affiliation: Cardiovascular Research Laboratories Laboratory, Research Institute of the McGill University Health Centre, Montréal, Québec H4A 3J1, Canada.

ABSTRACT
Apolipoprotein (apo) mimetic peptides replicate some aspects of HDL function. We have previously reported the effects of compound ATI-5261 on its ability to replicate many functions of native apo A-I in the process of HDL biogenesis. ATI-5261 induced muscle toxicity in wild type C57Bl/6 mice, increased CPK, ALT and AST and increase in triglyceride (Tg) levels. Aromatic phenylalanine residues on the non-polar face of ATI-5261, together with positively charged arginine residues at the lipid-water interface were responsible for these effects. This information was used to create a novel analog (CS-6253) that was non-toxic. We evaluated this peptide designed from the carboxyl terminus of apo E, in its ability to mimic apo A-I functionality. Our data shows that the lipidated particles generated by incubating cells overexpressing ABCA1 with lipid free CS-6253 enhances the rate of ABCA1 lipid efflux with high affinity interactions with native ABCA1 oligomeric forms and plasma membrane micro-domains. Interaction between ABCA1 and lipid free CS-6253 resulted in formation of nascent HDL-CS-6253 particles that are actively remodeled in plasma. Mature HDL-CS-6253 particles deliver cholesterol to liver cells via SR-BI in-vitro. CS-6253 significantly increases cholesterol efflux in murine macrophages and in human THP-1 macrophage-derived foam cells expressing ABCA1. Addition of CS-6253 to plasma dose-dependently displaced apo A-I from α-HDL particles and led to de novo formation of preβ-1 HDL that stimulates ABCA1 dependent cholesterol efflux efficiently. When incubated with human plasma CS-6253 was also found to bind with HDL and LDL and promoted the transfer of cholesterol from HDL to LDL predominantly. Our data shows that CS-6253 mimics apo A-I in its ability to promote ABCA1-mediated formation of nascent HDL particles, and enhances formation of preβ-1 HDL with increase in the cycling of apo A-I between the preβ and α-HDL particles in-vitro. These mechanisms are potentially anti-atherogenic.

No MeSH data available.


Related in: MedlinePlus

Time dependent effects of incubation of lipid free CS-6253 with human plasma, on HDL subparticles.(A, B, C). Radiolabeled Lipid free apoA-I was prepared as indicated in “Material and Methods”. 125I-lipid free apoA-I in incubated with normolipidemic plasma, using molar ratio (10 μg Lipid free apoA-I or peptide: 1 μg plasma apoA-I) at 37°C for increasing time for (5 min, 1h, 2h, and 4h) at 37°C. Samples were separated by 2D-PAGGE, and 125I-apoA-I was detected by autoradiography. Lipid-free 125I-apoA-I (C) incubated in PBS for 4 h at 37°C is shown as controls. Molecular size markers are shown.
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pone.0131997.g009: Time dependent effects of incubation of lipid free CS-6253 with human plasma, on HDL subparticles.(A, B, C). Radiolabeled Lipid free apoA-I was prepared as indicated in “Material and Methods”. 125I-lipid free apoA-I in incubated with normolipidemic plasma, using molar ratio (10 μg Lipid free apoA-I or peptide: 1 μg plasma apoA-I) at 37°C for increasing time for (5 min, 1h, 2h, and 4h) at 37°C. Samples were separated by 2D-PAGGE, and 125I-apoA-I was detected by autoradiography. Lipid-free 125I-apoA-I (C) incubated in PBS for 4 h at 37°C is shown as controls. Molecular size markers are shown.

Mentions: Cholesterol efflux results in Fig 7C showed that PEG precipitated plasma with peptide at (1:1 mole ratio relative to apo A-I) increased preβ-1 HDL 4-fold (±1.12SD), as determined by densitometry analysis, when compared to non-treated plasma (Fig 7D). Having observed efficient increase of ABCA1 mediated cholesterol efflux to CS-6253 in plasma or in plasma molar ratios relative to apo A-I, we investigated the effects of CS-6253 on HDL particles by 2D-PAGGE (Fig 8A, 8B, 8C and 8D). We observed that in a time-course manner the peptide altered the size distribution of the larger HDL-apo A-I species α-1 and α-2 with ratio of (1:10) (Fig 8A, 8B, 8C and 8D) with near-complete conversion of α to preβ-1 HDL achieved at 5 min or 2h. This was associated with dramatic increase in preβ-1 particles, 31-fold after 5min and 26-fold after 2h (Fig 8A and 8C). Interestingly, we found that the CS-6253 peptide itself is unable to associate with preβ-1 HDL, and as it bound only to α–HDL species as judged by 2D-PAGGE and CS-6253 Western blots using CS-6253 specific anti-body (Fig 8E and 8F). CS-6253 or 125I-Lipid free apoA-I (control) were incubated with normolipidemic plasma ratio (10 μg Lipid free apoA-I or peptide: 1 μg plasma apoA-I) at 37°C for increasing time. When 125I-lipid free apoA-I was added to plasma we observed only a 0.23-fold increase in preβ-1 particles after 5min and 0.4-fold increase after 2h (Fig 9B and 9C).


Novel Apo E-Derived ABCA1 Agonist Peptide (CS-6253) Promotes Reverse Cholesterol Transport and Induces Formation of preβ-1 HDL In Vitro.

Hafiane A, Bielicki JK, Johansson JO, Genest J - PLoS ONE (2015)

Time dependent effects of incubation of lipid free CS-6253 with human plasma, on HDL subparticles.(A, B, C). Radiolabeled Lipid free apoA-I was prepared as indicated in “Material and Methods”. 125I-lipid free apoA-I in incubated with normolipidemic plasma, using molar ratio (10 μg Lipid free apoA-I or peptide: 1 μg plasma apoA-I) at 37°C for increasing time for (5 min, 1h, 2h, and 4h) at 37°C. Samples were separated by 2D-PAGGE, and 125I-apoA-I was detected by autoradiography. Lipid-free 125I-apoA-I (C) incubated in PBS for 4 h at 37°C is shown as controls. Molecular size markers are shown.
© Copyright Policy
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC4514675&req=5

pone.0131997.g009: Time dependent effects of incubation of lipid free CS-6253 with human plasma, on HDL subparticles.(A, B, C). Radiolabeled Lipid free apoA-I was prepared as indicated in “Material and Methods”. 125I-lipid free apoA-I in incubated with normolipidemic plasma, using molar ratio (10 μg Lipid free apoA-I or peptide: 1 μg plasma apoA-I) at 37°C for increasing time for (5 min, 1h, 2h, and 4h) at 37°C. Samples were separated by 2D-PAGGE, and 125I-apoA-I was detected by autoradiography. Lipid-free 125I-apoA-I (C) incubated in PBS for 4 h at 37°C is shown as controls. Molecular size markers are shown.
Mentions: Cholesterol efflux results in Fig 7C showed that PEG precipitated plasma with peptide at (1:1 mole ratio relative to apo A-I) increased preβ-1 HDL 4-fold (±1.12SD), as determined by densitometry analysis, when compared to non-treated plasma (Fig 7D). Having observed efficient increase of ABCA1 mediated cholesterol efflux to CS-6253 in plasma or in plasma molar ratios relative to apo A-I, we investigated the effects of CS-6253 on HDL particles by 2D-PAGGE (Fig 8A, 8B, 8C and 8D). We observed that in a time-course manner the peptide altered the size distribution of the larger HDL-apo A-I species α-1 and α-2 with ratio of (1:10) (Fig 8A, 8B, 8C and 8D) with near-complete conversion of α to preβ-1 HDL achieved at 5 min or 2h. This was associated with dramatic increase in preβ-1 particles, 31-fold after 5min and 26-fold after 2h (Fig 8A and 8C). Interestingly, we found that the CS-6253 peptide itself is unable to associate with preβ-1 HDL, and as it bound only to α–HDL species as judged by 2D-PAGGE and CS-6253 Western blots using CS-6253 specific anti-body (Fig 8E and 8F). CS-6253 or 125I-Lipid free apoA-I (control) were incubated with normolipidemic plasma ratio (10 μg Lipid free apoA-I or peptide: 1 μg plasma apoA-I) at 37°C for increasing time. When 125I-lipid free apoA-I was added to plasma we observed only a 0.23-fold increase in preβ-1 particles after 5min and 0.4-fold increase after 2h (Fig 9B and 9C).

Bottom Line: We have previously reported the effects of compound ATI-5261 on its ability to replicate many functions of native apo A-I in the process of HDL biogenesis.CS-6253 significantly increases cholesterol efflux in murine macrophages and in human THP-1 macrophage-derived foam cells expressing ABCA1.When incubated with human plasma CS-6253 was also found to bind with HDL and LDL and promoted the transfer of cholesterol from HDL to LDL predominantly.

View Article: PubMed Central - PubMed

Affiliation: Cardiovascular Research Laboratories Laboratory, Research Institute of the McGill University Health Centre, Montréal, Québec H4A 3J1, Canada.

ABSTRACT
Apolipoprotein (apo) mimetic peptides replicate some aspects of HDL function. We have previously reported the effects of compound ATI-5261 on its ability to replicate many functions of native apo A-I in the process of HDL biogenesis. ATI-5261 induced muscle toxicity in wild type C57Bl/6 mice, increased CPK, ALT and AST and increase in triglyceride (Tg) levels. Aromatic phenylalanine residues on the non-polar face of ATI-5261, together with positively charged arginine residues at the lipid-water interface were responsible for these effects. This information was used to create a novel analog (CS-6253) that was non-toxic. We evaluated this peptide designed from the carboxyl terminus of apo E, in its ability to mimic apo A-I functionality. Our data shows that the lipidated particles generated by incubating cells overexpressing ABCA1 with lipid free CS-6253 enhances the rate of ABCA1 lipid efflux with high affinity interactions with native ABCA1 oligomeric forms and plasma membrane micro-domains. Interaction between ABCA1 and lipid free CS-6253 resulted in formation of nascent HDL-CS-6253 particles that are actively remodeled in plasma. Mature HDL-CS-6253 particles deliver cholesterol to liver cells via SR-BI in-vitro. CS-6253 significantly increases cholesterol efflux in murine macrophages and in human THP-1 macrophage-derived foam cells expressing ABCA1. Addition of CS-6253 to plasma dose-dependently displaced apo A-I from α-HDL particles and led to de novo formation of preβ-1 HDL that stimulates ABCA1 dependent cholesterol efflux efficiently. When incubated with human plasma CS-6253 was also found to bind with HDL and LDL and promoted the transfer of cholesterol from HDL to LDL predominantly. Our data shows that CS-6253 mimics apo A-I in its ability to promote ABCA1-mediated formation of nascent HDL particles, and enhances formation of preβ-1 HDL with increase in the cycling of apo A-I between the preβ and α-HDL particles in-vitro. These mechanisms are potentially anti-atherogenic.

No MeSH data available.


Related in: MedlinePlus