Topical delivery of DNA oligonucleotide to induce p53 generation in the skin via thymidine dinucleotide (pTT)-encapsulated liposomal carrier

Abstract

Introduction Transcription factor p53 has a powerful tumor suppressing function that is associated with many cancers. Since the molecular weight of p53 is 53 kDa, it is difficult to transport across cell membranes. Thymidine dinucleotide (pTT) is an oligonucleotide that can activate the p53 transcription factor and trigger the signal transduction cascade. However, the negative charge and high water solubility of pTT limit its transport through cellular membranes, thereby preventing it from reaching its target in the nucleus. A suitable delivery carrier for pTT is currently not available. Objective The purpose of this study was to employ a nanoscale liposomal carrier to resolve the delivery problem, and increase the bioavailability and efficiency of pTT. Methodology The approach was to employ liposomes to deliver pTT and then evaluate the particle size and zeta potential by laser light scattering (LLS), and permeation properties of pTT in vitro in a Franz diffusion assembly, and in vivo in a murine model using confocal laser scanning microscopy (CLSM). Results We found that dioleoylphosphatidylethanolamine (DOPE) combined with cholesterol 3 sulfate (C3S) were the best ingredients to achieve an average desired vehicle size of 133.6 ± 2.8 nm, a polydispersity index (PDI, representing the distribution of particle sizes) of 0.437, and a zeta potential of −93.3 ± 1.88. An in vitro penetration study showed that the liposomal carrier was superior to the free form of pTT at 2–24 hours. CLSM study observed that the penetration depth of pTT reached the upper epidermis and potential of penetration maintained up to 24 hours. Conclusion These preliminary data demonstrate that nanosized DOPE/C3S liposomes can be exploited as a potential carrier of drugs for topical use in treating skin diseases.

Andrographolide Loaded Topical Nanocarriers for Management of Psoriasis: A Safe and Effective Approach

“…The prepared liposomes were stable and delivered both the drugs at a predetermined rate which showed the effectiveness of the liposomal delivery system for the treatment of skin conditions (Kochar et al, 2020). Various studies have reported effective skin permeability using liposomal nanocarrriers (Fang et al, 2011;Amer et al, 2019;Vyas et al, 2013). Formulation with higher lipid (Guggu lipid) concentration showed good drug retention after 24 h. The formulation was stable at higher temperature for longer duration.…”