BACKGROUND
Despite improvement in insulin preparation and delivery, the use of insulin therapy alone to maintain normal glucose concentration and prevent the development of diabetic complication is not easy. Therefore, there has been considerable interest in developing gene therapy to supply insulin. We investigated that the administration of hemagglutinating virus of Japan (HVJ)- liposome complex, containing human insulin construct into the portal vein to control the blood glucose level in murine streptozotocin (STZ)-induced diabetes. METHODS: Human insulin gene was delivered to STZ-induced diabetic rats through the portal vein using HVJ-liposome containing Epstein-Barr virus (EBV) replicon-based plasmid (pEB). Blood glucose and body weight were measured after insulin gene delivery. The animals were sacrificed 28 days later and the livers were collected for immuno-histochemical staining of insulin. In addition plasma insulin and C-peptide levels were measured. RESULTS: Significant decrease in blood glucose levels and an increase in insulin and C-peptide levels were observed in the insulin gene transfection group as compared to the control group. Immunohistochemical staining of insulin also showed significant differences between these two groups. CONCLUSION: This study demonstrated the possibility of insulin gene therapy through the portal vein using pEB and HVJ-liposome method to produce a sustained improvement of diabetic glucose metabolism.