INVESTIGADORES
DORFMAN Damian
congresos y reuniones científicas
Título:
THERAPEUTIC EFFICACY OF MELATONIN IN REDUCING RETINAL DAMAGE IN AN EXPERIMENTAL MODEL OF EARLY TYPE 2 DIABETES IN RATS
Autor/es:
ROSENSTEIN RE; BORDONE M; CHIANELLI MS; KELLER SARMIENTO MI; DORFMAN D; MIRANDA M; SALIDO EM
Lugar:
Seattle
Reunión:
Congreso; The Association For Research In Vision And Ophthalmology (Arvo); 2013
Institución organizadora:
ARVO
Resumen:
Invest Ophthalmol Vis Sci 2013;54: E-Abstract 291.© 2013 ARVO
291?D0240
THERAPEUTIC EFFICACY OF
MELATONIN IN REDUCING RETINAL DAMAGE IN AN EXPERIMENTAL MODEL OF EARLY TYPE 2
DIABETES IN RATS
Ruth
Rosenstein1, Melina Bordone1, Monica Chianelli1,
María Keller Sarmiento1, Damian Dorfman1, Magdalena
Miranda1 and Ezequiel Salido1
1 Dept Human
Biochem-Sch Med, University of Buenos Aires, Buenos Aires, Argentina
Commercial Relationships: Ruth Rosenstein, None; Melina
Bordone, None; Monica Chianelli, None; María Keller
Sarmiento, None; Damian Dorfman, None; Magdalena Miranda,
None; Ezequiel Salido, None
Support: None
Abstract
Purpose:Diabetic retinopathy is a leading
cause of acquired blindness in adults, mostly affected by type 2 diabetes
mellitus (T2DM). We have developed an experimental model of early T2DM in adult
rats by combining diet-induced insulin resistance and a slight β-cell secretory impairment, which
mimics some features of human T2DM at its initial stages, and provokes
significant retinal alterations. The aim of the present work was to analyze the
effect of melatonin on retinal changes induced by a moderate metabolic
derangement.
Methods:Adult male Wistar rats received a
control diet or 30% sucrose in the drinking water ad libitum. Three weeks after
this treatment, animals were injected with vehicle or streptozotocin (STZ, 25
mg/kg). One day after vehicle or STZ injection, animals were subcutaneously
implanted with a pellet of melatonin, which was replaced every 15 days. At 12
weeks of treatment, fasting and postprandial glycemia, and glucose and insulin
tolerance tests were analyzed. Retinal function (scotopic elctroretinograms),
retinal lipid peroxidation (thiobarbituric acid reactive substance levels), NOS
activity (using 3H-arginine), TNFα (enzyme-linked immunosorbent assay), retinal morphology (optical
microscopy), and Müller cells glial fibrillary acidic protein (GFAP) and
vascular endothelial growth factor levels (VEGF) (immunohistochemistry) were
evaluated.
Results:Animals which received a
sucrose-enriched diet and STZ showed significant differences in metabolic
tests, as compared with control groups. Melatonin, which did not affect glucose
metabolism in control or diabetic rats, prevented the decrease in the
electroretinogram a-and b-wave, and oscillatory potential amplitude, and the
increase in retinal lipid peroxidation, NOS activity, TNFα and Müller cell GFAP and VEGF
levels.
Conclusions:These results indicate that
melatonin protected the retina from the alterations observed in an experimental
model of diabetic retinopathy associated with type 2 diabetes.
Keywords: 590 melatonin ? 499 diabetic
retinopathy ? 637 pathology: experimental