糖尿病真皮组织中细胞的增殖和凋亡状态

目的研究在未受到外源损伤时,糖尿病真皮组织中细胞的行为表现特征。方法以糖尿病患者(糖尿病组)和非糖尿病对照者(对照组)的皮肤组织标本作为研究对象,分别进行组织学观察,免疫组化检测PCNA、cyclin B1的表达,TUNEL法检测凋亡细胞,组织蛋白提取ELISA法测定p53、Bcl-2和Bax表达水平。结果与对照组相比,糖尿病组真皮组织胶原排列松散杂乱,纤细的浅层胶原范围广。两组真皮组织中PCNA、cyclin B1和Bax表达无明显差别;与对照组相比,糖尿病组真皮组织中凋亡细胞表达明显增加(P<0.01),p53水平增高而Bcl-2水平减低(均P<0.05)。结论无外源性损伤时,糖尿病真皮组织已有病理改变。凋亡细胞比例增加,相关的凋亡调控蛋白表达异常。提示糖尿病创面有一个异常的愈合起点。

Cell proliferation and apoptosis in diabetic dermal tissues

Objective To evaluate the cell proliferation and apoptosis in diabetic dermal tissues under intact skin. Methods Skin biopsy specimens from diabetic patients(diabetic group) and non-diabetic patients(control group) were collected.The cutaneous histological characteristics were observed.The PCNA and cyclin B1 expressions were dectected by immunohistochemistry,the apoptotic cells were expressed by TUNEL assay and the content of p53,Bcl-2 and Bax in skin tissue were assayed by ELISA. Results Compared with the control group,the collagen fibrils were shortened,thinned and disorganized in the dermal tissues of the diabetic group.There were no differences in the expressions of PCNA,cyclin B1 and Bax between the two groups.More apoptotic cells,increased level of p53 and decreased level of Bcl-2 were observed in the diabetic skin tissues(both P<0.05). Conclusion Collagen alteration,increased apoptotic cells and abnormal expression of apoptosis-related proteins preexist under intact diabetic skin.This underlying disorder may play an important role in the increased susceptibility to injury and the formation of non-healing wounds in diabetic patients.