Multiple Triphenylphosphonium Cations as a Platform for the Delivery of a Pro-Apoptotic Peptide

• Published in: Pharmaceutical research 2011-11, Vol.28 (11), p.2780-2789
• Main Authors: Kolevzon, Netanel, Kuflik, Uriel, Shmuel, Miriam, Benhamron, Sandrine, Ringel, Israel, Yavin, Eylon
• Format: Article
• Language: English
• Subjects: Annexin A5 - metabolism; Apoptosis; Apoptosis - drug effects; Apoptosis - physiology; Apoptosis Regulatory Proteins - metabolism; Biochemistry; Biomedical and Life Sciences; Biomedical Engineering and Bioengineering; Biomedicine; Cations - analysis; Cations - chemical synthesis; Cations - pharmacology; Cations - toxicity; Cell Culture Techniques; Drug Compounding - methods; Drug Delivery Systems; Fluorescein-5-isothiocyanate - metabolism; Fluorescein-5-isothiocyanate - pharmacology; Fluorescent Dyes - metabolism; Fluorescent Dyes - pharmacology; HeLa Cells; Humans; Medical Law; Mitochondria; Mitochondria - metabolism; Molecular Targeted Therapy; Organophosphorus Compounds - analysis; Organophosphorus Compounds - chemical synthesis; Organophosphorus Compounds - pharmacology; Organophosphorus Compounds - toxicity; Peptides; Peptides - analysis; Peptides - chemical synthesis; Peptides - metabolism; Peptides - pharmacology; Peptides - toxicity; Pharmacology/Toxicology; Pharmacy; Propidium - metabolism; Research Paper; Toxicity
• ISSN: 0724-8741; 1573-904X
• DOI: 10.1007/s11095-011-0494-6

ABSTRACT Purpose Triphenyl phosphonium cations (TPPs) are delocalized lipophilic cations that accumulate in the mitochondria of cells. We have explore the effect of increasing the number of TPPs on delivery of a cell-impermeable pro-apoptotic peptide to intact cells. Methods The pro-apoptotic peptide D-(KLAKLAK) 2 (KLA) was extended with 0–3 L-Lysines modified at their ε-amine with TPP. Peptides were studied in HeLa cells to determine their cytotoxic activity and cellular uptake. Results In HeLa cells, the increased cytotoxicity correlates with the number of TPPs; the peptide with 3 TPP molecules (3-KLA) exerts the highest cytotoxic activity. This FITC-labeled peptide is found to accumulate in intact HeLa cells, whereas peptides with 0–2 TPPs are not detected at the same peptide concentration. Mitochondria-dependent apoptosis of HeLa cells in the presence of 3-KLA was followed by propidium iodide, Annexin-V and DiOC fluorescence by FACS. Conclusion A facile synthetic methodology has been presented for the delivery of a biologically active peptide into mitochondria of intact cells by attaching multiple TPP moieties to the peptide. This approach was shown to dramatically increase biological activity of the peptide as a pro-apoptotic agent.