Involvement of Endocytosis in the Transdermal Penetration Mechanism of Ketoprofen Nanoparticles

Abstract

We previously designed a novel transdermal formulation containing ketoprofen solid nanoparticles (KET-NPs formulation), and showed that the skin penetration from the KET-NPs formulation was higher than that of a transdermal formulation containing ketoprofen microparticles (KET-MPs formulation). However, the precise mechanism for the skin penetration from the KET-NPs formulation was not clear. In this study we investigated whether energy-dependent endocytosis relates to the transdermal delivery from a 1.5% KET-NPs formulation. Transdermal formulations were prepared by a bead mill method using additives including methylcellulose and carbopol 934. The mean particle size of the ketoprofen nanoparticles was 98.3 nm. Four inhibitors of endocytosis dissolved in 0.5% DMSO (54 μM nystatin, a caveolae-mediated endocytosis inhibitor; 40 μM dynasore, a clathrin-mediated endocytosis inhibitor; 2 μM rottlerin, a macropinocytosis inhibitor; 10 μM cytochalasin D, a phagocytosis inhibitor) were used in this study. In the transdermal penetration study using a Franz diffusion cell, skin penetration through rat skin treated with cytochalasin D was similar to the control (DMSO) group. In contrast to the results for cytochalasin D, skin penetration from the KET-NPs formulation was significantly decreased by treatment with nystatin, dynasore or rottlerin with penetrated ketoprofen concentration-time curves (AUC) values 65%, 69% and 73% of control, respectively. Furthermore, multi-treatment with all three inhibitors (nystatin, dynasore and rottlerin) strongly suppressed the skin penetration from the KET-NPs formulation with an AUC value 13.4% that of the control. In conclusion, we found that caveolae-mediated endocytosis, clathrin-mediated endocytosis and macropinocytosis are all related to the skin penetration from the KET-NPs formulation. These findings provide significant information for the design of nanomedicines in transdermal formulations.

Development of Sustained-Release Ophthalmic Formulation Based on Tranilast Solid Nanoparticles

“…We have also reported the method for preparing solid nanoparticles using bead mill treatment and showed that the addition of HPβCD and MC enhances the dispersion stability and crushing force, respectively [15,[17][18][19]. In addition, our previous studies using indomethacin showed a hydrophilic gel base, such as carbopol, provides for a high drug release of solid nanoparticles from the gel [15,[17][18][19]. Based on these findings, HPβCD, MC and carbopol were selected as components of TL-NPs-Gel in this study.…”

“…Type SM-4 methylcellulose (MC) and 2-hydroxypropyl-β-cyclodextrin (HPβCD) were provided by Shin-Etsu Chemical Co., Ltd. (Tokyo, Japan) and Nihon Shokuhin Kako Co., Ltd. (Tokyo, Japan), respectively. The HPβCD and MC were selected to enhance the dispersion stability and crushing force, respectively [15,[17][18][19]. Mixtures of these reagents (TL powder, MC and HPβCD) were dispersed in distilled water, and zirconia beads (0.1 mm in diameter) were added.…”

“…TL release from the TL formulations was evaluated as in previous studies using a Franz diffusion cell [15,[17][18][19]. Briefly, a 220 nm-pore size MF™-MEMBRANE FILTER (Merck Millipore, Tokyo, Japan) was set into a Franz diffusion cell and 0.3 g of 0.75% TL formulation was applied to the filter.…”

“…With these impediments, it is essential to search for an alternative ophthalmic delivery system while simultaneously improving drug absorption into the ocular tissues. On the other hand, we previously reported that formulations containing solid nanoparticles are safe, since these formulations do not involve toxic solvents in their preparation, such as surface-active agents, and show high penetration into skin tissues [17][18][19]. Therefore, we investigated whether a DDS based on solid nanoparticles can release drugs into the aqueous humor through the eyelid.…”

Stem cell membrane-coated isotretinoin for acne treatment

“…However, the mechanism of transdermal delivery has not been thoroughly investigated [23]. While most transdermal mechanisms focused on keratin, few studies have reported the role of tight junctions [24] and cell endocytosis [25].…”