Morris G M, Hopewell J W, Harold M, Ross G A, Nadejina N M, Gusev I, Flockhart I
Research Institute, University of Oxford, Churchill Hospital, UK.
Cell Prolif. 1997 Aug-Sep;30(8-9):311-23. doi: 10.1111/j.1365-2184.1997.tb00944.x.
The daily topical application of two compounds, a cream containing 10% evening primrose oil (EPO) and Lioxasol (a compound used clinically to treat radiation burns), resulted in increased cell proliferative activity in the skin of female Large White pigs. The effect was most pronounced in the case of the EPO based cream, and was comparable in magnitude with that observed in a previous study on pig skin using orally administered EPO. There was an increase in the size of the rete pegs in the epidermis by 6 weeks after the start of application of the EPO cream. However, this did not translate into an increase in the total thickness of the viable epidermis (excluding the stratum corneum) due to a reduction in the density of rete pegs, from 2 weeks after treatment. Lioxasol had no overall effect on the size of the rete pegs. The labelling index (LI) of cells in the basal layer of the epidermis of pigs receiving a daily topical application of EPO increased progressively with time from the start of application. The LI was maximal (17.9 +/- 2.4%) at the end of the observation period (8 weeks) at which time it was a factor of approximately 2 higher than in the basal layer prior to treatment. A considerably less marked increase in the LI of the basal layer was seen after the application of Lioxasol. The overall increase was approximately 20%, relative to the LI in the untreated epidermis. Labelled cell nuclei were also counted in the papillary dermis. After the application of the EPO cream, no significant increase in the number of labelled cells was observed until week 8, at which time values were approximately twice those in untreated skin. In Lioxasol treated skin the effect on the numbers of labelled cells in the papillary dermis was more immediate, with a approximately 60% increase at 2 weeks. This enhanced level of labelling was maintained until the end of the observation period of 10 weeks. Studies on the cell kinetics of the skin using the alcohol component of the Lioxasol preparation suggested that alcohol rather than Lioxasol was the most significant ingredient. It was concluded that the EPO cream merited further evaluation as a potential modulator of skin response to ionizing radiation.
每日局部应用两种化合物，一种是含有10%月见草油（EPO）的乳膏和Lioxasol（一种临床上用于治疗放射性烧伤的化合物），这导致雌性大白猪皮肤中的细胞增殖活性增加。基于EPO的乳膏效果最为显著，其程度与先前一项使用口服EPO的猪皮肤研究中观察到的相当。在开始应用EPO乳膏6周后，表皮中的 rete 钉突大小增加。然而，由于治疗2周后 rete 钉突密度降低，这并未转化为有活力表皮（不包括角质层）总厚度的增加。Lioxasol对 rete 钉突的大小没有总体影响。每日局部应用EPO的猪表皮基底层细胞的标记指数（LI）从应用开始随时间逐渐增加。在观察期结束时（8周）LI最大（17.9 +/- 2.4%），此时它比治疗前基底层中的LI高出约2倍。应用Lioxasol后，基底层LI的增加明显较少。相对于未处理表皮中的LI，总体增加约20%。还对乳头层真皮中的标记细胞核进行了计数。应用EPO乳膏后，直到第8周才观察到标记细胞数量有显著增加，此时的值约为未处理皮肤的两倍。在Lioxasol处理的皮肤中，对乳头层真皮中标记细胞数量的影响更为直接，在2周时增加约60%。这种增强的标记水平一直维持到10周的观察期结束。使用Lioxasol制剂中的酒精成分对皮肤细胞动力学进行的研究表明，酒精而非Lioxasol是最重要的成分。得出的结论是，EPO乳膏作为皮肤对电离辐射反应的潜在调节剂值得进一步评估。
