In Vitro Cellular Delivery of Peptide Nucleic Acid (PNA)

One of the major challenges facing modern biochemical and biomedical technologies are finding molecular tools for diagnosis and detection of genetic diseases. In this connection, several classes of oligonucleotides have been developed that can recognize and bind to DNA and RNA with high affinity and sequence selectivity and withstand enzymatic degradation by proteases and nucleases; however, few can traverse the cell membrane on their own. One such promising class of nucleic acid mimics developed in the last two decades which showed good results in vitro, are the peptide nucleic acids (PNAs). New chiral α- and γ-peptide Nucleic Acid (PNA) submonomer with methyl substituents in pseudopeptide backbone were synthesized via Mitsunobu reaction. The α-(R)-/γ-(S)-configuration of the chiral centres will ensure the preorganization of the PNA oligomer into a right-handed helix. The results obtained showed that Boc/Fmoc-submonomer compatible with Boc-protocol PNAs solid-phase synthesis on an MBHA resin. We synthesized simple and efficient α-R-, γ-S-disubstituted PNA submonomer based on L-Ala and D-Ala with the construction of the intermediate pseudopeptide moiety by Mitsunobu reaction for subsequent use in the Boc-Protocol of solid phase PNA synthesis.

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Orexigenic and cytoprotective effects of a novel adenosine-enriched peptide nucleic acid compound: Implications for clinical application

Journal of Clinical Oncology ◽

10.1200/jco.2007.25.18_suppl.14154 ◽

2007 ◽

Vol 25 (18_suppl) ◽

pp. 14154-14154 ◽

Cited By ~ 1

Author(s):

J. T. D’Olimpio ◽

S. Elliston ◽

M. Dediego ◽

R. Sodum

Keyword(s):

Wound Healing ◽

Nucleic Acid ◽

Cell Lines ◽

Receptor Binding ◽

Adenosine Receptors ◽

Peptide Nucleic Acid ◽

Hek293 Cell ◽

Smooth Muscle Relaxation ◽

A2 Receptors

14154 Background: There is a major unmet need for new non-toxic orexigenic and cytoprotective agents that can ameliorate intractable symptoms in cancer such as anorexia, poor wound healing/ulcerations and poor QoL. Underlying causes of these clinical problems include excessive inflammatory/cytokine responses to either treatment related or tumor related processes, or to both at once. AVR118, a novel remarkably non-toxic peptide/nucleic acid formulation has been shown in many anecdotal reports and in small clinical trials, to stimulate appetite, improve fatigue, and assist in more rapidly reversing toxic side effects of chemotherapy, radiation and interferon therapy. It has now been re-characterized to better explain these multiple effects. It binds to adenosine receptors in vitro and increases cAMP release in HEK293 cell lines expressing A2 receptors, mechanistically involving targeted receptor binding, most likely in the gut and in the functional pathway of orexin A. Methodologies: HPLC, co-chromatography with standards, UV and mass spectrometry. Receptor binding/functional assays in vitro, animal models for anti-inflammatory and wound healing studies. Results: AVR 118 consists of a mix of 14 nucleoside derivatives, including available adenosine at a concentration of 2.1mM in stable solution. Also present is a complex aggregate of peptides showing high proline and tyrosine content. AVR 118 binds to adenosine receptors in vitro and increases cAMP release in HEK293 cell lines containing A2 receptors and enhances smooth muscle relaxation mediated by A2 and others such as NK2 and NTS1 in vitro. AVR 118 shows 20% enhancement of epithelialization when compared to saline controls in a controlled porcine wound healing model. Conclusions: AVR 118 may prove to play a major role in palliation of anorexia symptoms associated with serious debilitating diseases such as cancer or AIDS and as adjunctive therapy for these patients. [Table: see text] No significant financial relationships to disclose.

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