Treatment of anaemia with iron complexes

The comparison of iron(II) and iron(III) uptake by mammalian intestine has recently been the focus of intense research effort. In a study of 14 different iron preparations in man, Dietzfelbinger [100] showed that the iron(III) preparations, without exception, had a lower bioavailability than iron(II) sulphate and were therefore of dubious therapeutic efficacy. Unfortunately, orally administered iron(II) sulphate generates hydroxyl radicals in the gastrointestinal tract of mammals [101], This property, together with the associated acidity of iron(II) sulphate, may cause irritation and damage to the mucosa. A wide range of side effects have been reported for iron(II) sulphate [102]. Thus, should an efficiently absorbed iron(III) complex be identified, it would be of therapeutic benefit. 

The non-toxic 3-hydroxypyrones (Structure 12) bind iron(III) forming water-soluble complexes [44], In the pH range 4-7, they possess a lower affinity for iron(III) than EDTA, and by virtue of the kinetic lability of such complexes, are able to donate iron to high-affinity binding sites, while minimizing non-selective binding to foodstuffs. Thus, iron presented as a maltol complex is relatively well absorbed [103,104], In contrast, the presence of EDTA reduces iron absorption by the intestine. Ferric maltol is the only simple iron(III) preparation which compares favourably with iron(II) sulphate [105], and in contrast to iron(II) sulphate, there are few, if any, side effects associated with the oral administration of ferric maltol. Consequently, patient compliance is likely to be superior with this iron preparation. 

Free radicals in central nervous system injury 

Central Nervous System Diseases Research, The Upjohn Company, Kalamazoo, MI 49001, USA 

The purpose of this chapter is to present some of the evidence concerning the involvement of free radicals in acute CNS injury and their relationship to specific pathophysiological events. A great deal of this information has been obtained from investigations demonstrating the protective efficacy of lipid antioxidant agents in experimental models of acute spinal cord or head injury. 

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