Early iron deficiency produces persistent damage to visual tracts in Wistar rats

Abstract

In this study, morphological changes in the optic nerve were determined by light microscopy in Wistar rats on an iron-deficient diet for 32 days or for 21 days followed by 10 days on an iron-recovery diet. The morphometric findings showed significantly fewer blood vessels and oligodendrocytes in the iron-deficient rats and iron-recovery rats than in the control group, as well as more astrocytes in the iron-recovery rats. Serum iron levels of the iron-deficient rats were significantly lower than those of the controls. On the other hand, iron-recovery rats had normal serum iron levels, but no change in the abnormal morphology of the myelinated axons and morphometric parameters. Our data indicate that iron is necessary for maintenance of the optic nerve cell structure, and morphological damage from iron-deficiency is not easily reverted by iron reposition.

Assessing the critical period for Rho kinase activity during Drosophila ventral furrow formation

“…In embryos that are mutant for fog, T48, or dia (Diaphanous, a formin), myosin II fails to accumulate (Dawes-Hoang et al, 2005; Developmental Dynamics Kolsch et al, 2007;DeMaman et al, 2008). In fog and T48 mutants, Rho-GEF2, which activates Rok, is not recruited efficiently to the apical surface.…”

Effectiveness of iron repletion in the diet for the optic nerve development of anaemic rats

“…56,65 The densities of oligodendrocytes, astrocytes, blood vessels, and damaged myelinated fibres of the rat ON were influenced by iron deficiency during the first few weeks of life. 37 The percentage of myelin occupancy for axons of methamphetamine-treated animals was significantly affected, and the average myelin area was reduced. 31 Further investigations are needed to explain the detailed role of iron to the visual system.…”

“…The experimental design effectively produced maternal iron-deficient anaemia, which indicated low iron status of their offspring. 37 A similar experimental regime has been used elsewhere. 9,55,56 Dietary iron deficiency results in a wide variety of structural and physiological defects 22,56,57 and a decrease in lipids and proteins on myelin.…”

“…27,28 The visual pathways are vulnerable structures to insults such as deficiency diet, drugs of abuse, and alcohol. [29][30][31][32][33][34][35][36][37] In this study, we examined the effect of iron repletion administrated after weaning on the ON development of rats fed with an iron-deficient diet since birth until the postnatal day (PND 21). The quantitative changes analysed in the ON of iron-deficient rats and after iron repletion provides a baseline pattern to the ON damage, which will lead to a better understanding of the ophthalmologic alterations found in children breastfed from anaemic women.…”

Estudo estrutural e quantitativo do nervo óptico de ratos Wistar com anemia ferropriva submetidos à estimulação tátil e recuperados nutricionalmente

“…Estudos recentes mostram que a ingestão de dieta com níveis inadequados de ferro pode causar alterações em parâmetros morfológicos e morfométricos, revelando atrasos no desenvolvimento de animais deficientes neste microelemento (De Maman, Homem & Lachat, 2008;De Maman, Melo, Homem, Tavares & Lachat, 2010) e que um período curto de severa carência de ferro na dieta em animais jovens resulta em prejuízos ao sistema nervoso que não foram corrigidos após suplementação com ferro, mesmo que outros sinais da deficiência tenham sido revertidos (Feelt & Lozoff, 1996;De Maman et al, 2010).…”