Glucose- and metabolically regulated hepatic insulin gene therapy for diabetes.
OBJECTIVE
The purpose of this study was to examine glucose- and metabolically modulation of insulin secretion by rAAV-mediated gene delivery in vitro and in vivo.


METHODS
A recombinant adeno-associated virus vector (rAAV) containing a furin-mutated human insulin gene, driven by the rat insulin I promoter, was used in this study. Glucose-responsive secretion of human insulin was determined by treating rAAV-transduced Huh7 human hepatoma cells with varying concentrations of glucose, with or without insulin secretagogues. Glucose- and metabolically modulated secretion of human insulin in the streptozotocin (STZ)-induced diabetic mice was assessed by intrahepatic administration of rAAV-polyethylenimine (PEI) complexes, followed by intraperitoneal glucose tolerance test (IPGTT), with or without theophylline.


RESULTS
Glucose- and metabolically controlled human insulin secretion was obtained in the rAAV-transduced Huh7 cells. Treatment of STZ-induced diabetic animals with rAAV-polyethylenimine (rAAV-PEI) complexes resulted in production of human insulin and amelioration of hyperglycemia. Co-administration of glucose and theophylline in these animals augmented the secretion of human insulin, demonstrating metabolic modulation of insulin secretion in vivo. Immunohistochemical examination of the liver sections of rAAV-treated mice confirmed the production of human insulin.


CONCLUSIONS
Glucose- and metabolically controlled hepatic insulin gene therapy was obtained both in vitro and in vivo.
Hsu
Paul Yueh-Jen
PY
School of Pharmacy, College of Medicine, National Taiwan University, Taipei, 100, Taiwan.
Kotin
Robert M
RM
Yang
Ya-Wun
YW
D000818:Animals; D003994:Bucladesine / Q000494:pharmacology; D005576:Colforsin / Q000494:pharmacology; D000229:Dependovirus / Q000235:genetics; D003921:Diabetes Mellitus, Experimental / Q000628:therapy*; D004305:Dose-Response Relationship, Drug; D015316:Genetic Therapy; D005947:Glucose / Q000494:pharmacology*; D007097:Imines / Q000494:pharmacology; D007150:Immunohistochemistry; D007328:Insulin / Q000235:genetics* / Q000378:metabolism; D000078790:Insulin Secretion; D008099:Liver / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D011095:Polyethylenes / Q000494:pharmacology; D013311:Streptozocin; D013806:Theophylline / Q000494:pharmacology
D007097:Imines; D007328:Insulin; D011095:Polyethylenes; C505405:poly(ethylene imine); D005576:Colforsin; D013311:Streptozocin; D003994:Bucladesine; D013806:Theophylline; D005947:Glucose