强脉冲光及射频对BALB/c小鼠皮肤胶原的影响

Effects of intense pulsed light and radiofrequency radiation on the content of collagen in BALB/c mouse skin

目的 探讨强脉冲光和射频对BALB/c小鼠皮肤的外观不良反应、组织病理、真皮厚度变化及胶原含量的影响。方法 将BALB/c小鼠随机分为强脉冲光照射组（IPL组）、射频照射组（RF组）、强脉冲光＋射频联合照射组（IPL联合RF组）及正常对照组。以强脉冲光和射频处理BALB/c小鼠皮肤，于各时间点观察各组小鼠皮肤外观局部不良反应发生率，取小鼠皮肤行HE染色 观察各组皮肤组织病理及真皮厚度变化，Masson染色分析各组小鼠皮肤组织胶原纤维的表达。 结果 强脉冲光和射频照射后小鼠皮肤局部无不良反应，处理8周后， IPL组、RF组及IPL联合RF组的真皮层均较正常对照组渐进性增厚趋势，胶原纤维增厚、增加，排列致密，细胞间基质逐渐增加，IPL联合RF组较IPL组、RF组更为明显，差异有统计学意义（P ＜ 0.05）。表皮未见明显增厚。 结论 强脉冲光和射频均可刺激真皮胶原纤维增加，联合强脉冲光和射频技术可以增强对胶原纤维的生物刺激作用。

Objective To investigate the effects of intense pulsed light （IPL） and radiofrequency radiation on the appearance, histopathological manifestation, dermal depth and collagen content in BALB/c mouse skin. Methods The back of BALB/c mice was irradiated with intense pulsed light （IPL group, n = 9）, radiofrequency （RF group, N = 9）, IPL and radiofrequency （IPL＋RF group, n = 9） respectively, for 4 sessions at 1-week intervals followed by 2 sessions at 2-week intervals. Three mice remaining untreated served as the control group. The appearance of skin on the back of mice was observed at different time points after irradiation. Some mice were sacrificed and skin specimens were obtained from the back at week 4, 8 and 12 after the first irradiation. Hematoxylin and eosin staining was performed to observe the histopathological manifestation and measure the dermal depth of mouse skin, and Masson staining to detect the expression of collagen fiber in mouse skin. Results No local adverse effects were observed in the back skin of mice after irradiation with IPL or radiofrequency. Since the 8th week after the first irradiation, the dermal layer had appeared to be thickened, with an increase in the content of collagen fiber and extracellular matrix, in the IPL group, RF group and IPL＋RF group compared with the control group, and the increase was more obvious in the IPL＋RF group than in the IPL group and RF group （all P 〈 0.05）. Increased collagen fiber was densely arranged in irradiated mice. There was no apparent thickening of skin epidermis after irradiation. Conclusions Both IPL and radiofrequency can stimulate an increase in dermal collagen production in mice, and a synergistic effect exists between IPL and radiofrequency in the biostimulation of collagen synthesis.