Effects of heme oxygenase-1 transgenic islets on transplantation.

Heme oxygenase-1 (HO-1) has been described as a protein capable of cytoprotection via radical scavenging and apoptosis prevention. The aim of this study was to analyze whether HO-1 overexpression in freshly isolated murine transgenic islets resulted in cell protection and improved in vivo functional performance after transplantation. We produced transgenic mice in which the human HO-1 transgene driven by chicken beta-actin promoter was expressed in the heart, liver, spleen, lung, kidney, muscle, intestine, and pancreas in Balb/c mice. One hundred fifty islets isolated from HO-1 transgenic and control Balb/c mice were syngeneically transplanted under the left kidney capsule of the streptozotocin-diabetic Balb/c mice. The recipients who underwent transplantation with HO-1 transgenic islets showed higher blood glucose than those with control islets at 4 weeks (320 +/- 25 vs 189 +/- 43 mg/dL; P < .05). Body weight was not significantly different between the 2 groups. Our data indicate transgenic islets with high HO-1 expression did not improve transplantation outcome.