title: The angiogenic response to PLL-g-PEG-mediated HIF-1α plasmid DNA delivery in healthy and diabetic rats.
abstract: Impaired angiogenesis is a major clinical problem and affects wound healing especially in diabetic patients. Improving angiogenesis is a reasonable strategy to increase diabetes-impaired wound healing. Recently, our lab described a system of transient gene expression due to pegylated poly-l-lysine (PLL-g-PEG) polymer-mediated plasmid DNA delivery in vitro. Here we synthesized peptide-modified PLL-g-PEG polymers with two functionalities, characterized them in vitro and utilized them in vivo via a fibrin-based delivery matrix to induce dermal wound angiogenesis in diabetic rats. The two peptides were 1) a TG-peptide to covalently bind these nanocondensates to the fibrin matrix (TG-peptide) for a sustained release and 2) a polyR peptide to improve cellular uptake of these nanocondensates. In order to induce angiogenesis in vivo we condensed modified and non-modified polymers with plasmid DNA encoding a truncated form of the therapeutic candidate gene hypoxia-inducible transcription factor 1α (HIF-1α). HIF-1α is the primarily oxygen-dependent regulated subunit of the heterodimeric transcription factor HIF-1, which controls angiogenesis among other physiological pathways. The truncated form of HIF-1α lacks the oxygen-dependent degradation domain (ODD) and therefore escapes degradation under normoxic conditions. PLL-g-PEG polymer-mediated HIF-1α-ΔODD plasmid DNA delivery was found to lead to a transiently induced gene expression of angiogenesis-related genes Acta2 and Pecam1 as well as the HIF-1α target gene Vegf in vivo. Furthermore, HIF-1α gene delivery was shown to enhance the number endothelial cells and smooth muscle cells - precursors for mature blood vessels - during wound healing. We show that - depending on the selection of the therapeutic target gene - PLL-g-PEG nanocondensates are a promising alternative to viral DNA delivery approaches, which might pose a risk to health.
authors: Laboratory for Biologically Oriented Materials, Department of Materials, ETH Zurich, CH-8093, Switzerland; University of Zurich, Institute of Veterinary Physiology, Winterthurerstrasse 260, CH-8057 Zurich, Switzerland. Electronic address: markus.thiersch@uzh.ch.
authors: Markus
authors: M
authors: Thiersch
authors: Laboratory for Biologically Oriented Materials, Department of Materials, ETH Zurich, CH-8093, Switzerland.
authors: Markus
authors: M
authors: Rimann
authors: Laboratory for Biologically Oriented Materials, Department of Materials, ETH Zurich, CH-8093, Switzerland.
authors: Vasiliki
authors: V
authors: Panagiotopoulou
authors: Laboratory for Biologically Oriented Materials, Department of Materials, ETH Zurich, CH-8093, Switzerland.
authors: Ece
authors: E
authors: Öztürk
authors: Tissue Biology Research Unit University Children's Hospital Zurich, CH-8008, Switzerland.
authors: Thomas
authors: T
authors: Biedermann
authors: BioInterface Group, Laboratory for Surface Science and Technology, Department of Materials, ETH Zurich, CH-8093, Switzerland.
authors: Marcus
authors: M
authors: Textor
authors: Laboratory for Biologically Oriented Materials, Department of Materials, ETH Zurich, CH-8093, Switzerland.
authors: Tessa C
authors: TC
authors: Lühmann
authors: Laboratory for Biologically Oriented Materials, Department of Materials, ETH Zurich, CH-8093, Switzerland.
authors: Heike
authors: H
authors: Hall
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D019556:COS Cells; D002196:Capillaries / Q000378:metabolism / Q000473:pathology; D002522:Chlorocebus aethiops; D004247:DNA / Q000378:metabolism*; D003921:Diabetes Mellitus, Experimental / Q000473:pathology / Q000628:therapy*; D003922:Diabetes Mellitus, Type 1 / Q000473:pathology / Q000628:therapy; D005337:Fibrin / Q000378:metabolism; D005786:Gene Expression Regulation; D018014:Gene Transfer Techniques; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000235:genetics* / Q000378:metabolism / Q000627:therapeutic use; D008969:Molecular Sequence Data; D018919:Neovascularization, Physiologic; D010957:Plasmids / Q000378:metabolism*; D011092:Polyethylene Glycols / Q000737:chemistry*; D011107:Polylysine / Q000031:analogs & derivatives* / Q000737:chemistry; D051381:Rats; D017207:Rats, Sprague-Dawley; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism; D014945:Wound Healing
chemical_list: D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D042461:Vascular Endothelial Growth Factor A; C443714:polylysine-graft-(poly(ethylene glycol)); D011107:Polylysine; D011092:Polyethylene Glycols; D005337:Fibrin; D004247:DNA