Abnormal Retinal Structure and Function of Mother Wistar Rats Supplemented Aspartame, Glutamate and Galactose

Abstract

Three dietary supplements are investigated in the present study. Aspartame is a low calorie sweetener utilized instead of sugar for diabetic patients. Monosodium Glutamate (MSG) is used in varieties of food stuffs to enhance food flavor. Meanwhile galactose is presents in many of food items such as milk, dairy products, fruits and vegetables and overloads enhanced aging like process and altered body function. The present work aimed to illustrate the effect of dietary supplements of aspartame, glutamate and galactose in retina of mother Wistar rats. Virgin Wistar rats were mated with fertile male and zero date of pregnancy was determined. Pregnant rats were orally administered aspartame (100 mg/kg), monosodium glutamate (500 mg/kg) and galactose (1 g/kg body weight) from 6th day of gestation until parturition and 21 days post-partum. Four main groups of pregnant rats were used; control, aspartame, glutamate and galactose treatment. Each animal group was composed of ten individuals. Mother rats were sacrificed at 21 days post-partum and their retinas were dissected and processed for histological, and transmission electron microscopic investigation. Biochemical assessments of vascular endothelial growth factor (VEGF), endothelin-1 (ET-1), adhesion molecules (ICAM-1 & VCAM-1), 8-hydroxy-deoxyguanosine (8-hdG), iron, and zinc content were done. The present findings revealed that the used dietary supplements induced retinal damage assessed by degeneration of ganglion cells, inner and outer nuclear layer and widespread necrotic patches of photoreceptor outer segment. A striking missing of outer nuclear and photoreceptor outer segments was detected post-glutamate treatment. Glutamate and galactose treatment showed apparent increase of pleomorphic and pyknotic nuclei of inner and outer nuclear cells. The retinal thickness was markedly decreased in experimental groups especially in those of glutamate treatment. Retinal serotonin, dopamine and zinc and iron contents were markedly depleted, however, VEGF and ICAM-1& VCAM-1 and 8-hydroxy-guanosine were overexpressed in experimentally-treated groups compared to the control. It can be concluded that the applied dietary supplements affected the retinal structure and function of mother rats.

Investigation of the Effects of Monosodium Glutamate on the Embryonic Development of the Eye in Chickens

“…It has also been reported to lead to degeneration of neurons in retinal layers, the arcuate nucleus, and various other brain regions, delaying the emergence of certain reflexes during neurobehavioral development and leading to temporary changes in reflex performance and motor coordination [ 59 , 60 ]. El-Sayyad et al [ 61 ] found that MSG given orally to pregnant rats significantly reduced total retinal thickness, outer and inner nuclear layers, and photoreceptor layer thickness. It has also been reported that mother rats have retinal ganglion degeneration, loss of pigment epithelium, and vacuolization in the plexiform inner layer.…”