Objective To compare the effect of transplant islets between the subcutaneous inguinal white adipose tissues and renal capsule in the treatment of type 1 diabetes mellitus in mouse models.
Methods The mice with type 1 diabetes mellitus undergoing islet transplantation were divided into the white adipose group (n=10) and renal capsule group (n=10). The islets were isolated, purified and transplanted to the subcutaneous white adipose tissues of inguinal region and renal capsule. The random blood glucose level and glucose tolerance function of the recipient mice in two groups were continuously monitored after operation. Islet grafts of the surviving recipient mice were harvested at postoperative 100 d for histopathological examination.
Results In the white adipose group, the blood glucose levels of 6 recipient mice were restored to normal at 1 month after transplantation, whereas the blood glucose levels of the other 4 recipient mice were high, which died before the end of monitoring. In the renal capsule group, the blood glucose levels of 10 recipient mice returned to normal within 10 d after transplantation. Islet grafts of the recipient mice in two groups could lower the blood glucose levels, whereas the islet grafts in the white adipose group required a longer time to exert the effect. The glucose tolerance function of the mice in the renal capsule group was significantly better than that of those in white adipose group (P < 0.05). Histopathological examination demonstrated that the insulin of the islet grafts was normally expressed in two groups.
Conclusions The islets transplanted into the subcutaneous white adipose tissues of inguinal region can play an effective role in regulating the changes of blood glucose level. Although the blood glucose-lowering function is slightly weaker than that of the islets graft in the renal capsule, it has multiple advantages resembling the ideal islet transplantation sites, which is a promising replacement site for islet transplantation.