Hegde Aswathi R, Rewatkar Prarthana V, Manikkath Jyothsna, Tupally Karnaker, Parekh Harendra S, Mutalik Srinivas
Department of Pharmaceutics, Manipal College of Pharmaceutical Sciences, Manipal University, Manipal 576104, Karnataka State, India.
School of Pharmacy, Pharmacy Australia Centre of Excellence (PACE), The University of Queensland, Brisbane, QLD 4072, Australia.
Eur J Pharm Sci. 2017 May 1;102:237-249. doi: 10.1016/j.ejps.2017.03.009. Epub 2017 Mar 8.
The aim of this study was to evaluate skin delivery of ketoprofen when covalently tethered to mildly cationic (2 or 4) peptide dendrimers prepared wholly by solid phase peptide synthesis. The amino acids glycine, arginine and lysine formed the dendrimer with ketoprofen tethered either to the lysine side-arm (N) or periphery of dendrimeric branches. Passive diffusion, sonophoresis- and iontophoresis-assisted permeation of each peptide dendrimer-drug conjugate (D1-D4) was studied across mouse skin, both in vitro and in vivo. In addition, skin toxicity of dendrimeric conjugates when trialed with iontophoresis or sonophoresis was also evaluated. All dendrimeric conjugates improved aqueous solubility at least 5-fold, compared to ketoprofen alone, while also exhibiting appreciable lipophilicity. In vitro passive diffusion studies revealed that ketoprofen in its native form was delivered to a greater extent, compared with a dendrimer-conjugated form at the end of 24h (Q (μg/cm): ketoprofen (68.06±3.62)>D2 (49.62±2.92)>D4 (19.20±0.89)>D1 (6.45±0.40)>D3 (2.21±0.19). However, sonophoresis substantially increased the skin permeation of ketoprofen-dendrimer conjugates in 30min (Q (μg/cm): D4 (122.19±7.14)>D2 (66.74±3.86)>D1 (52.10±3.22)>D3 (41.66±3.22)) although ketoprofen alone again proved superior (Q: 167.99±9.11μg/cm). Next, application of iontophoresis was trialed and shown to considerably increase permeation of dendrimeric ketoprofen in 6h (Q (μg/cm): D2 (711.49±39.14)>D4 (341.23±16.43)>D3 (89.50±4.99)>D1 (50.91±2.98), with a Q value of 96.60±5.12μg/cm for ketoprofen alone). In vivo studies indicated that therapeutically relevant concentrations of ketoprofen could be delivered transdermally when iontophoresis was paired with D2 (985.49±43.25ng/mL). Further, histopathological analysis showed that the dendrimeric approach was a safe mode as ketoprofen alone. The present study successfully demonstrates that peptide dendrimer conjugates of ketoprofen, when combined with non-invasive modalities, such as iontophoresis can enhance skin permeation with clinically relevant concentrations achieved transdermally.
本研究的目的是评估通过固相肽合成完全制备的轻度阳离子（2或4）肽树枝状大分子共价连接酮洛芬时的皮肤递送情况。氨基酸甘氨酸、精氨酸和赖氨酸形成树枝状大分子，酮洛芬连接在赖氨酸侧链（N）或树枝状分支的外围。研究了每种肽树枝状大分子-药物缀合物（D1-D4）在体外和体内通过小鼠皮肤的被动扩散、超声导入和离子导入辅助渗透。此外，还评估了离子导入或超声导入试验时树枝状缀合物的皮肤毒性。与单独的酮洛芬相比，所有树枝状缀合物的水溶性至少提高了5倍，同时也表现出明显的亲脂性。体外被动扩散研究表明，在24小时结束时，天然形式的酮洛芬比树枝状大分子缀合形式的递送程度更大（Q（μg/cm）：酮洛芬（68.06±3.62）>D2（49.62±2.92）>D4（19.20±0.89）>D1（6.45±0.40）>D3（2.21±0.19））。然而，超声导入在30分钟内显著增加了酮洛芬-树枝状大分子缀合物的皮肤渗透（Q（μg/cm）：D4（122.19±7.14）>D2（66.74±3.86）>D1（52.10±3.22）>D3（41.66±3.22）），尽管单独的酮洛芬再次被证明更优（Q：167.99±9.11μg/cm）。接下来，试验了离子导入的应用，结果表明在6小时内离子导入可显著增加树枝状酮洛芬通过皮肤的渗透（Q（μg/cm）：D2（711.49±39.14）>D4（341.23±16.43）>D3（89.50±4.99）>D1（50.91±2.98），单独的酮洛芬的Q值为96.60±5.12μg/cm）。体内研究表明，当离子导入与D2联合使用时，可经皮递送治疗相关浓度的酮洛芬（985.49±43.25ng/mL）。此外，组织病理学分析表明，树枝状大分子方法与单独使用酮洛芬一样是一种安全的方式。本研究成功证明，酮洛芬的肽树枝状大分子缀合物与离子导入等非侵入性方式联合使用时，可增强皮肤渗透，并经皮达到临床相关浓度。
