Evaluation of a Cationic Poly(β-hydroxyalkanoate) as a Plasmid DNA Delivery System

Abstract

Poly(β-hydroxyalkanoates) (PHAs) are biodegradable polymers produced by a wide range of bacteria. The structures of these polymers may be tuned by controlling the available carbon source composition, but the range of functional groups accessible in this manner is limited to those that the organism is able to metabolize. Much effort has been made to chemically modify the side chains of these polymers to achieve new materials with new applications. We have previously reported the synthesis of the first cationic PHA, poly(β-hydroxyoctanoate)-co-(β-hydroxy-11-(bis(2-hydroxyethyl)-amino)-10-hydroxyundecanoate) (PHON). Here, we report the use of this polymer as a plasmid DNA delivery system. PHON was found to bind and condense the DNA into positively charged particles smaller than 200 nm. In this manner, PHON was shown to protect plasmid DNA from nuclease degradation for up to 30 min. In addition, treatment of mammalian cells in vitro with PHON/DNA complexes resulted in luciferase expression as the result of the delivery of the encoded gene.

Recent progress in gene therapy to deliver nucleic acids with multivalent cationic vectors

“…Both properties inform about the electroneutrality ratio in terms of molar charge ratio ( eff = 1) or mass ratio ( / GV NA mm ) between the gene vector (m GV ) and nucleic acid (m NA ) masses. The electrostatic interaction in the complex may be also studied by conductivity [91] or, with less accuracy, by gel electrophoresis [92,93]. Fluorescence intercalation assays with ethidium bromide or GelRed, and circular dichroism have been used for monitoring the DNA compaction process by the gene vector together with the nature of the GV-NA interaction [77,[94][95][96].…”

“…(ii) multivalent cationic lipids [67,78,139,178,181], derivated oligoamines [182] and tripeptide multivalent lipids [122]; (iii) cationic polymers derivatives from PEI [124,127,183,184], PAMAM [132,140], PDMAEMA [123,133,185], PAA [103,131,186,187], chitosan [188], polyphosphoramidates [189], polyhydroxyalkanoate [92], polyamines [107], polyaminoacids [127,190] or diblock copolymers [191]; (iv) polycations from calixarene [40,136,165,192] or cyclodextrin [134,135,142,164,193] derivatives; (v) lipopolymers from lysine derivatives [170]; (vi) pendant polymercationic cyclodextrins [129,130,163]; and (vii) cationic polymer-cyclodextrin polyrotaxanes [89]. The picture that results from these transfection studies is that many of the polyplexes show efficacies comparable to that reported by the Lipo2000 positive control and also by most of the commercial or synthezised univalent CLs, but its efficacy as transfecting agents of DNA is still below than that reported by most of t...…”

“…In those cases, specific studies, such as DNA or RNA protection, degradation [92,124,140,193], internalization [105], DNase digestion [64], intracellular uptake and traffic [97, 105-107, 126, 127, 133, 139, 142, 184, 189-191, 203] localization or colocalization [140,190] and release [145], have been focused mainly in polyplexes (with cationic polymers or macrocyclic polycations) and, scarcely, for lipoplexes containing GCLs [64].…”

“…The results confirm that all these optimized formulations did not report any toxicity to the cell lines studied, the cell viability after transfection being considerably better than the commercial control Lipo2000. The cell viability/cytotoxicity of several complexes between nucleic acids and a wide variety of recent synthesized MVCVs has been analyzed: (i) GCLs as cholesterol-based with alkyl or oligo-oxyethylene spacers [118,119,121,206,207], aromatic-based with alkyl or oligo-oxyethylene spacers [46], ammonium derivatives [54,71,93] imidazolium derivatives [45,75,99] and pyridinium derivatives [57] with alkyl type spacers, aminoacid-based [64,208], SS14 linkers [66], gemini-like amphiphilic peptides [150] or cyclen-based CLs [120,180]; (ii) several MVCLs [67,72,122,181,182]; (iii) cationic polymer-derivatives from PEI [124,127,183,209], PAMAM [140], PDMAEMA [123,133], chitosan [188], polyphosphoramidates [189], polyhydroxyalkanoates [92], polyamines [107,187] or polyaminoacids [127,190]; (iv)…”

Synthesis of a novel 4H-pyran analog as minor groove binder to DNA using ethidium bromide as fluorescence probe

“…It is the carrier of hereditary information and involved in the biological synthesis of enzymes and proteins via transcription and replication [1,2]. DNA is most important cellular target for many natural and synthetic organic molecules, especially, anticancer and antiviral drugs [3][4][5]. Binding of small molecules with DNA is very important for designing low-toxic drugs for clinical use [1] because the binding modes and binding properties during the interaction can help us to understand the functional mechanism of drugs and provide theoretical background for the development of new drugs targeted to DNA [3][4][5].…”