脂肪干细胞在糖尿病大鼠急性放射性皮肤损伤治疗中的作用

Adipose-Derived Stem Cells Alleviate Acute Radiation-induced Skin Injury in Diabetic Rats

目的研究脂肪干细胞(ADSCs)对糖尿病大鼠急性放射性皮肤损伤的治疗作用。方法采用高脂饲料喂养联合低剂量链脲佐菌素注射的方法,构建2型糖尿病大鼠模型;后续采用单次90 Gy放射线照射糖尿病大鼠腹股沟区皮肤,构建糖尿病大鼠放射性皮肤损伤模型。从雄性SD大鼠腹股沟区脂肪组织中分离、提取、鉴定、扩增脂肪干细胞,并将放射性皮肤损伤的糖尿病大鼠随机分为对照组(n=6)与实验组(ADSCs组,n=6)。实验组给予ADSCs移植,对照组仅给予PBS注射。于放射线造模后第3周,分别采用皮肤损伤反应评分、苏木精-伊红染色、免疫荧光染色、酶联免疫吸附测定(ELISA)、TUNEL染色等方法评价ADSCs对糖尿病大鼠放射性皮肤损伤模型的治疗效果。结果两组糖尿病大鼠随机血糖均≥16.70 mmol/L、胰岛数量显著减少。ADSCs组大鼠皮肤损伤反应评分在放射后第2周和第3周分别为(3.41±0.27)和(3.25±0.11),显著低于对照组(4.66±0.10)和(5.25±0.11)(均P<0.01);ADSCs组皮肤厚度为(526.54±67.92)μm,显著低于对照组[(1029.69±196.03)μm,P<0.05];ADSCs组在400倍镜视野下淋巴细胞数量为(126.52±13.77)个,显著低于对照组[(243.56±48.16)个,P<0.05];ADSCs组血清中TNF-α、IL-4的含量分别为(2.38±0.008)ng/L、(7.67±0.63)ng/L,显著低于对照组[(3.68±0.42)ng/L、(11.71±0.51)ng/L,均P<0.01],ADSCs组血清中IL-13的含量为(18.42±2.77)ng/L,与对照组(21.52±2.94)ng/L相近,差异没有统计学意义(P>0.05);ADSCs组TUNEL阳性细胞比例为(17.96±2.29)%,显著低于对照组[(30.87±3.41)%,P<0.05]。结论ADSCs通过降低皮肤损伤反应评分、抑制炎症细胞浸润和炎症因子释放以及抑制细胞凋亡等减轻糖尿病大鼠急性放射性皮肤损伤。

Objective To investigate the therapeutic effect of adipose stem cells(ADSCs)on acute radiation-induced skin injury in diabetic rats.Methods Type 2diabetic rat model was constructed by high-fat diet combined with low-dose streptozotocin injection.Single 90Gy irradiation was performed on the inguinal region skin of diabetic rats to construct a radiation-induced skin injury model on diabetic rat.The therapeutic effect of adipose stem cells was investigated on this model.ADSCs were isolated,extracted,identified and amplified from the adipose tissue of the male SD rats inguinal region,and the diabetic rats with radioactive skin injury were randomly divided into control group(n=6)and experimental group(also called ADSCs group,n=6).The therapeutic effects of ADSCs on the diabetic rat model of radioactive skin injury were evaluated by skin injury response score,HE staining,immunofluorescence staining,enzyme-linked immunosorbent assay(ELISA),and TUNEL staining,at the 3 rd week after radiographic modeling.Results Random blood glucose of diabetic rats in both groups was≥16.70mmol/L,and the number of islets was significantly reduced.The skin injury response scores of ADSCs group were(3.41±0.27)and(3.25±0.11)at week 2and week 3after radiation,which were significantly lower than those of control group(4.66±0.10)and(5.25±0.11)(P<0.01).The skin thickness of ADSCs group was(526.54±67.92)μm,which was significantly lower than that of control group(1029.69±196.03)μm(P<0.05).The number of lymphocytes in ADSCs group was(126.52±13.77),significantly lower than that in control group(243.56±48.16)(P<0.05).The contents of TNF-αand IL-4in serum of ADSCs group were(2.38±0.008)ng/L and(7.67±0.63)ng/L,respectively,which were significantly lower than those of control group(3.68±0.42)ng/L and(11.71±0.51)ng/L(both P<0.01).The content of IL-13in serum of ADSCs group was(18.42±2.77)ng/L,which was similar to that of control group(21.52±2.94)ng/L,with no statistical significance(P>0.05).The proportion of TUNEL positive cells in ADSCs group was(17.96±2.29)%,which was significantly lower than that in control group(30.87±3.41)%(P<0.05).Conclusion ADSCs can reduce skin injury response score,inhibit inflammatory cell infiltration and inflammatory factor release,and inhibit cell apoptosis in the treatment of acute radioactive skin injury in diabetic rats.