目的:观察人脂肪源性血管基质成分(stromal vascular fractions,SVF)对中波紫外线(ultraviolet B,UVB)诱导的裸大鼠皮肤光老化的影响。方法:6周龄裸大鼠随机分为正常对照组及实验组,实验组持续UVB照射8周建立皮肤光老化模型并随机分为模型组,以及SVF低剂量(low-dose,LD)、中剂量(middle-dose,MD)和高剂量(high-dose,HD)(100μL悬液中的细胞数分别为10~4、10~5和10~6)治疗组;采用酶消化法提取健康女性脂肪组织中的SVF,分别取低、中、高剂量的SVF悬液注射于裸大鼠背部皮下;模型组注射相同剂量的生理盐水,正常对照组不做任何处理;7 d后取材,观察注射部位表皮厚度及结构的改变;28 d后取材观察注射部位真皮厚度及结构的改变。结果:SVF治疗7 d后,中、高剂量治疗组裸大鼠皮肤较实验对照组表皮层厚度减小、角质层比例下降、基底层处于异常增殖状态的细胞核减少(P〈0.05)。治疗28 d后,中剂量及高剂量治疗组Ⅰ型胶原蛋白mRNA相对表达量增加,Ⅲ型胶原蛋白及基质金属蛋白酶-3(matrix metalloproteinases-3,MMP-3)mRNA相对表达量下降(P〈0.05),高剂量治疗组皮肤真皮层厚度增加(P〈0.05)。结论:SVF具有抗皮肤光老化的潜能,有潜在的临床应用价值。
AIM: To investigate the anti-aging effect of the stromal vascular fractions( SVF) injection in photo-aging skin of nude rats. METHODS: Six-week-old nude rats were divided into control group and photoaging group. The nude rats in photoaging group were continuously irradiated with ultraviolet B( UVB) for 8 weeks to build the photoaging skin model,and were randomly divided into placebo group,and low-dose( LD),middle-dose( MD) and high-dose( HD)SVF treatment groups. The human SVF was obtained by trypsin digestion from the adipose tissue in healthy females,and was subcutaneously injected into the back skin of photoaging nude rats in LD,MD and HD SVF treatment groups( 10~4,10~5 and 10~6cells in 100 μL suspension,respectively). The animals in photoaging skin model group were treated with placebo.Control group did not have any intervention. The changes in the thickness of epidermis and histology after 7 d and the thickness of the dermis and histology after 28 d were examined. RESULTS: The thickness of the epidermis was thinner in MD and HD SVF treatment groups than that in photoaging skin model group after 7 d( P〈0. 05). The percentage of stratum corneum and the abnormal proliferation of the epidermal basal cell layer were reduced( P〈0. 05). After 28 d,MD and HD SVF treatment groups showed that the content of collagen Ⅰ was higher than that in photoaging skin model group( P〈0. 05),and the contents of collagen Ⅲ and MMP3 were decreased( P〈0. 05). The dermis in HD group was thicker than that in photoaging skin model group( P〈0. 05). CONCLUSION: SVF may have anti-aging potential in photoaging skin and also has clinical application value.