人胰岛在分离、纯化过程中的细胞凋亡及氧化损伤

目的 探讨胰岛在获取、分离及纯化等过程中出现细胞凋亡的相关因素及应对策略.方法 经供者腹主动脉灌注4℃的UW液后,切取供者胰腺,并进行胶原酶灌注、消化及梯度离心,分离、提取胰岛.分别于胶原酶灌注前、灌注后、消化后及胰岛分离后等时点,采用原位末端标记法(TUNEL法)检测胰岛细胞凋亡情况,采用比色法检测超氧化物歧化酶(SOD)与丙二醛(MDA)水平,采用HE染色和双硫腙染色观察胰岛的形态学改变.结果 在分离、纯化胰岛的各个过程中,均出现了胰岛细胞凋亡的现象,其中在胶原酶灌注后和消化后最为明显,并伴随MDA的高表达,表达水平分别为(6.18±2.38)nmol/mgprot和(9.21±2.75)nmol/mgprot,均明显高于灌注前的(4.21±1.83)nmol/mgprot(P＜0.05和P＜0.01);而此时SOD水平则显著下降,至胰岛分离后仍处于较低水平,与灌注前相比,差异均有统计学意义(P＜0.05和P＜0.01).胶原酶灌注前,胰岛结构完整;胶原酶灌注后,胰岛周围组织结构膨胀;消化后,胰岛膜性结构被破坏,但能勉强维持岛状结构;胰岛分离后结构基本完整.结论 在提取胰岛的过程中,胶原酶灌注及消化可引起胰岛细胞凋亡,其机制可能与氧化损伤有关,抗氧化措施可作为移植前保护胰岛的手段.

Abstract：

Objective To observe the changes of islet cell apoptosis and oxidation-antioxidation before the transplantation, and to explore the pathways of islet protection. Methods Fifteen human pancreases were perfused with the Hanks solution containing collagenase, then digested and isolated. During the procedure, islet cell apoptosis was detected by TUNEL, SOD and MDA in the pancreas were measured by colorimetric method, and the morphologic changes were observed by H-E staining and dithizone staining. Results In the procedure of human islet isolation, especially in the stage of digestion, the apoptosis of human islet cells occurred. In the stages of perfusion and digestion, the MDA contents reached the high levels (6. 18 ± 2. 38 and 9. 21 ± 2. 75 umol/mg protein respectively),and the structures of the islets and tissues around the islets were damaged. Conclusion In the stages of perfusion and digestion, apoptosis of islet cells can be caused by oxidation. It suggests that antioxidation is a pathway for protection of islets before transplantation.

Apoptosis and oxidative injury of donor islets during isolation and purification

Objective To observe the changes of islet cell apoptosis and oxidation-antioxidation before the transplantation, and to explore the pathways of islet protection. Methods Fifteen human pancreases were perfused with the Hanks solution containing collagenase, then digested and isolated. During the procedure, islet cell apoptosis was detected by TUNEL, SOD and MDA in the pancreas were measured by colorimetric method, and the morphologic changes were observed by H-E staining and dithizone staining. Results In the procedure of human islet isolation, especially in the stage of digestion, the apoptosis of human islet cells occurred. In the stages of perfusion and digestion, the MDA contents reached the high levels (6. 18 ± 2. 38 and 9. 21 ± 2. 75 umol/mg protein respectively),and the structures of the islets and tissues around the islets were damaged. Conclusion In the stages of perfusion and digestion, apoptosis of islet cells can be caused by oxidation. It suggests that antioxidation is a pathway for protection of islets before transplantation.