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Impact of hydrophobic chain composition on amphiphilic macromolecule antiatherogenic bioactivity.

ABSTRACT: Amphiphilic macromolecules (AMs) composed of sugar backbones modified with branched aliphatic chains and a poly(ethylene glycol) (PEG) tail can inhibit macrophage uptake of oxidized low-density lipoproteins (oxLDL), a major event underlying atherosclerosis development. Previous studies indicate that AM hydrophobic domains influence this bioactivity through interacting with macrophage scavenger receptors, which can contain basic and/or hydrophobic residues within their binding pockets. In this study, we compare two classes of AMs to investigate their ability to promote athero-protective potency via hydrogen-bonding or hydrophobic interactions with scavenger receptors. A series of ether-AMs, containing methoxy-terminated aliphatic arms capable of hydrogen-bonding, was synthesized. Compared to analogous AMs containing no ether moieties (alkyl-AMs), ether-AMs showed improved cytotoxicity profiles. Increasing AM hydrophobicity via incorporation of longer and/or alkyl-terminated hydrophobic chains yielded macromolecules with enhanced oxLDL uptake inhibition. These findings indicate that hydrophobic interactions and the length of AM aliphatic arms more significantly influence AM bioactivity than hydrogen-bonding.

SUBMITTER: Faig A

PROVIDER: S-EPMC4157764 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature

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Impact of hydrophobic chain composition on amphiphilic macromolecule antiatherogenic bioactivity.

Faig Allison A Petersen Latrisha K LK Moghe Prabhas V PV Uhrich Kathryn E KE

Biomacromolecules 20140806 9

Amphiphilic macromolecules (AMs) composed of sugar backbones modified with branched aliphatic chains and a poly(ethylene glycol) (PEG) tail can inhibit macrophage uptake of oxidized low-density lipoproteins (oxLDL), a major event underlying atherosclerosis development. Previous studies indicate that AM hydrophobic domains influence this bioactivity through interacting with macrophage scavenger receptors, which can contain basic and/or hydrophobic residues within their binding pockets. In this st ...[more]

PMID: 25070717

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Impact of hydrophobic chain composition on amphiphilic macromolecule antiatherogenic bioactivity.

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Impact of hydrophobic chain composition on amphiphilic macromolecule antiatherogenic bioactivity.

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