微针对5- 氨基酮戊酸经皮渗透的作用研究

Effect of microneedle on transdermal permeation of 5-aminolevulinic acid

摘要:

目的 研究微针作用于鲜红斑痣鸡冠模型后，5- 氨基酮戊酸（5-ALA）代谢产生的原卟啉IX（PpIX）在鸡冠组织中含量变化，观察是否可增强5-ALA 渗透。方法 以鸡冠为模型，分为5-ALA 组和微针联合5-ALA 组，5-ALA 组鸡冠直接涂抹5-ALA，微针联合ALA 组用皮肤滚针滚磨鸡冠后涂抹5-ALA，均以未处理侧为自身对照，荧光分光光度计测定5-ALA 在鸡冠组织中合成PpIX 的情况，倒置荧光相差显微镜观察PpIX 在鸡冠组织中的分布。结果 在鸡冠组织内，5-ALA 吸收后产生的PpIX 量随时间逐渐增加，3 h出现明显聚集，4 h 达到高峰，6 h 后明显减少，微针联合5-ALA 组PpIX 含量高于单纯5-ALA 组，且荧光强度下降更慢，差异有统计学意义（P <0.05）。冷冻切片显示PpIX 弥漫性分布于表皮层和真皮血管组织中，微针联合5-ALA 组荧光强度高于5-ALA 组。结论 微针作用可促进5-ALA 渗透，为临床更好的使用光敏剂5-ALA 提供了实验依据。

Abstract:

Objective To determine the content of protoporphyrin IX (PpIX) in chicken comb tissues after using microneedles and topical application of 5-aminolevulinic acid (5-ALA), so as to observe whether microneedles can help 5-ALA permeate through epidermis of the comb. Methods Using chicken comb as the animal modle of port wine stain, the chickens were divided into ALA group and microneedle combined with ALA group. In the ALA group, 5-ALA was applied only; in the microneedle combined with ALA group, the chicken comb was applied with 5-ALA after grinding with microneedles; both groups used untreated side as self-control. The localization of PpIX was observed under inverted fluorescence phase contrast microscope, and the fluorescence intensity of PpIX was calculated by fluorospectrophotometer. Results In the comb, PpIX content increased gradually after applying ALA and reached the peak level at 4 hours in the two groups, and obviously decreased after 6 hours, but the PpIX level in the microneedle combined with ALA group was significantly higher than that in the ALA group (P < 0.05). Inverted fluorescence phase contrast microscopy showed that PpIX distributed evenly in the vascular tissue of epidermis and dermis, and the fluorescent intensity in the microneedle combined with ALA group was stronger than that in the ALA group. Conclusions Microneedles can help 5-ALA better permeate through epidermis. This experiment also provides reference base for optimizing 5-ALA usage in clinic.