Stage-dependent effect of pancreatic transplantation on diabetic ocular complications in the Spontaneously Diabetic Torii rat.
BACKGROUND
In terms of the temporal relationship between pancreas transplantation (PTx) and reversal of diabetic ocular complications, it has been difficult but important to determine a "point of no return." Thus, it is of great clinical interest to evaluate the efficacy of PTx on diabetic ocular complications.


METHODS
A spontaneous type 2 diabetic model of Spontaneously Diabetic Torii (SDT; RT1) rats was used in the present study, and syngeneic PTx was performed.


RESULTS
In the control SDT rats that received no treatment, hyperglycemia (>250 mg/dL) was developed from 25.2+/-3.9 weeks of age. Lens opacity was observed in all rats at 15 weeks after the onset of diabetes. Fluorescein angiography and immunohistochemistry detected the nonperfusion area and neovascularization in the retina at 5 weeks of diabetes. Daily insulin treatment could not prevent or reverse the ocular changes in our experiment. Fluorescein filling defect of the retinal vessels was observed at 10 weeks of diabetes. However, in the PTx rats, normoglycemia was achieved at all experimental time points. Diabetic cataract and retinopathy could have been prevented and improved if PTx had been performed at 5 weeks, but not at 10 weeks after the onset of diabetes. With PTx treatment, an inhibition of angiogenesis in the retina at 5 weeks after the onset of diabetes was demonstrated by immunohistochemistry.


CONCLUSIONS
Our results indicate that the potential use of the SDT rat for diabetes study and the positive effect of PTx performed before the "point of no return" could prevent and cure diabetic ocular complications.
Miao
Gang
G
Department of Surgery, Osaka University Graduate School of Medicine, Japan.
Ito
Toshinori
T
Uchikoshi
Fumihiro
F
Kamei
Motohiro
M
Akamaru
Yusuke
Y
Kiyomoto
Tetsuma
T
Komoda
Hiroshi
H
Nozawa
Masumi
M
Matsuda
Hikaru
H
D000818:Animals; D001786:Blood Glucose; D002386:Cataract / Q000453:epidemiology / Q000473:pathology / Q000517:prevention & control*; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology / Q000473:pathology / Q000601:surgery*; D003930:Diabetic Retinopathy / Q000453:epidemiology / Q000473:pathology / Q000517:prevention & control*; D004195:Disease Models, Animal; D015994:Incidence; D008297:Male; D010179:Pancreas / Q000473:pathology / Q000601:surgery; D016035:Pancreas Transplantation; D051381:Rats; D011922:Rats, Mutant Strains
D001786:Blood Glucose