Neuroprotective Effect Of An Antioxidant Lutein In The Diabetic Retina

Abstract

Purpose: : The influence of oxidative stress has been reported in the pathogenesis of diabetic complications. We have proposed the possibility of using an antioxidant, lutein, for preventing diabetic retinal degeneration (M. Sasaki et al. Diabetologia, 2010). In this study, we further investigated the long-term neuroprotective effect of lutein in the diabetic retina.

Methods: : C57BL/6 mice with streptozotocin-induced diabetes were constantly fed either a lutein-supplemented diet or a control diet from the onset of diabetes and their metabolic data were recorded. Visual function was evaluated by electroretinograms. Histological changes were observed in the retinal sections.

Results: : Lutein did not affect the metabolic status of the diabetic mice for 6 months. Although no changes were detected in both a- and b-waves of electroretinograms in the 1-month-diabetic mice, in 6-months-diabetic mice, the amplitudes were decreased and the implicit times were prolonged. However, the constant lutein intake prevented these changes of the b-wave(p<0.01). The thickness of the inner plexiform (IPL) and nuclear (INL) layers, and ganglion cell number were decreased in 6-month-diabetic mice, but all these changes were prevented by the constant lutein intake (IPL ; p<0.01, INL ; p<0.05 ; ganglion cells ; p<0.05).

Conclusions: : Lutein preserved better visual function and avoided histological changes in 6-months diabetes. The antioxidant, lutein may be a potential therapeutic approach to protect visual function in diabetes.

Keywords: neuroprotection • antioxidants • diabetes