Morphological changes induced in the brain of rats exposed prenatally to iron and the possible protective role of folic acid

ABSTRACT

Iron supplementation is recommended during pregnancy to meet the demands of both the mother and rapidly growing fetus. However, newborns and particularly preterm infants are highly susceptible to free radical oxidative damage resulting from iron. Folic acid supplementation is needed during pregnancy and it has been shown to reduce the tissue damage resulting from iron induced oxidative stress. Thirty pregnant female albino rats were used in this experiment and divided into three groups [A, B, C]. Group [A] Was kept as control. Group [B] Treated with iron gluconate orally in a dose of 50 mg/kg for eleven days [from day 6-16] of gestation. Group [C] Treated with the same dose of iron glunonate concomitantly with folic acid in a dose of 5mg/kg for the same previous duration. Samples from the brain striatum of newborns were taken and processed for light and electron microscopic investigation. The light microscopic examination of striatal area of group [B] showed necrotic changes appeared in some neurons in the form of shrinkage and condensation in their nuclei, others appeared degenerated with irregular nuclear outline and multiple vacuoles in their cytoplasm. Aggregated glial cells were observed around the blood capillary and mitotic division could be detected in some of them. Enhanced level of glial fibrillary acidic protein [GFAP] was observed in comparison to control group. Multiple iron deposits in the cytoplasm of neurons and glial cells were observed in group [B] animals. Marked improvement was observed in both neurons and glial cells of group [C]. Electron microscopy revealed apoptotic changes affecting mainly glial cells and some neurons in group [B] associated with swelling of Golgi cisternae and vacuolated mitochondria. Marked improvement was observed in both neurons and glial cells of group [C]. These results indicate that folic acid appears to reduce the iron induced neuronal damage in the brain of newly born rats exposed prenatally to iron