脐带干细胞减轻重度烧伤大鼠心脏损伤的研究

Effects of the umbilical cord stem cells on alleviating the cardiac injury in severe burn rats

目的探讨脐带干细胞对重度烧伤大鼠心脏损伤的保护治疗作用。方法将30只SD大鼠随机分为假伤组、烧伤组和干细胞组。烧伤组和干细胞组建立头颈背部35%TBSAⅢ度烧伤大鼠模型,干细胞移植后24 h,采集血液和心脏标本。免疫组化法检测脐带干细胞在心脏中的分布,以及检测中性粒细胞和巨噬细胞的浸润程度。HE染色检测心脏的结构。血生化自动分析仪检测血清肌钙蛋白I、肌酸激酶以及肌酸激酶同工酶的含量。数据行单因素方差分析、LSD-t检验。结果脐带干细胞经静脉血迁移入损伤的心脏,集中分布在心肌的小血管内。脐带干细胞可显著降低重度烧伤大鼠心脏中中性粒细胞和巨噬细胞的浸润程度,以及可显著减轻其心脏结构的损伤。此外,烧伤组中肌钙蛋白I、肌酸激酶、肌酸激酶同工酶含量较假伤组显著升高,而干细胞组三者的含量则显著低于烧伤组,差异具有统计学意义(P<0.05)。结论脐带干细胞迁移归巢重度烧伤大鼠心脏组织后,通过降低炎性细胞的浸润程度而发挥有效保护心脏的作用。

Objective To study the protective effects of umbilical cord stem cells on cardiac injury in severely burned rats. Methods 30 SD rats were randomly divided into sham group, burn group and stem cells treatment group. The severely burned head, neck and back of rat model of 35% TBSA Ⅲ degree was eatabished in burn and stem cells treatment groups. The blood and cardiac tissues were collected at 24 hours after stem cells transplantation. The distribution patterns of umbilical cord stem cells in cardiac tissues, and infiltrations of neutro- phils and macrophages in cardiac tissues were detected by immunohistochemistry staining method. The cardiac structures of rats were evaluated by HE staining. The levels of Troponin I, Creatine Kinase and Creatine Kinase- MB in serum were detected by the blood biochemical automatic analyzer. Results The umbilical cord stem cells migrated into the injured cardiac tissues and mainly concentrated in capillaries of heart. The umbilical cord stem cells significantly decreased neutrophils and macrophages infiltration of the cardiac tissues, and markedly alleviated structure damages of the cardiac tissues in severely burned rats. Furthermore, the levels of Troponin I, Creatine Kinase, Creatine Kinase-MB of burn group were significantly higher than that of sham group, but those of stem cells treatment group were markedly lower than that of burn group （P 〈 0.05）. Conclution The umbilical cord stem cells transplantation could effectively reduce inflammatory cells infiltration of the cardiac tissues, then protected the structure and function of the heart in severely burned rats.