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A Tripeptide-Stabilized Nanoemulsion of Oleic Acid
Published on: February 27, 2019
Multiple triphenylphosphonium cations as a platform for the delivery of a pro-apoptotic peptide
Netanel Kolevzon1, Uriel Kuflik, Miriam Shmuel
1Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 91120, Israel.
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.
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