ABSTRACT
According to the oxidative stress theory iron may play an important role in the pathogenesis of neurodegenerative diseases, as e.g. Parkinson's disease (PD). This review presents the results of studies, obtained by various methods, of iron in substantia nigra (SN)--a cerebral structure which degenerates in PD--and shows controversies concerning the amount of iron, its redox state, and the iron binding compounds. Taking into account all published experimental results, the increase in the concentration of iron in parkinsonian SN vs. control may be estimated as (3 +/- 5)%. The presence of large amounts of divalent iron in post mortem SN can be unequivocally negated. It is, however, still possible that iron is involved in the pathogenesis of PD, as even minor changes in the amount and form of iron may initiate processes leading to cells death.
Subject(s)
Iron/metabolism , Parkinson Disease/metabolism , Parkinson Disease/physiopathology , Substantia Nigra/metabolism , Substantia Nigra/physiopathology , HumansABSTRACT
We used Mössbauer spectroscopy to study the iron content, the redox state, and the binding site of iron in substantia nigra (SN) from parkinsonian (PD) and control brains. Measurements performed on fresh-frozen, formalin-fixed, and lyophilized samples demonstrated the presence of ferric (Fe3+) iron only, both in PD and control SN. Ferrous iron, if present at all, may represent at most 5% of the total iron. We found no difference in the total amount of iron in SN between PD and control brains. The Mössbauer spectra observed at 4.1 K in fresh (frozen or lyophilized) samples were different from those obtained in formalin-fixed (frozen or lyophilized) samples. In the fresh samples, only ferritin-like iron was observed, whereas in the samples frozen or lyophilized from formalin, non-ferritin iron was detected.
Subject(s)
Iron/analysis , Parkinson Disease/pathology , Substantia Nigra/pathology , Aged , Aged, 80 and over , Female , Ferric Compounds/analysis , Ferritins/analysis , Ferrous Compounds/analysis , Humans , Male , Middle Aged , Reference Values , Spectroscopy, MossbauerABSTRACT
Mössbauer spectroscopy was used to study iron content, its redox state and binding sites in substantia nigra from parkinsonian and control brains. Measurements performed on fresh frozen samples demonstrated the presence of ferric iron only, both in disease and control. We found no difference in the total amount of iron in substantia nigra between the disease and control. Mössbauer spectra observed at 4.1 K in fresh frozen samples were different from those obtained in formalin fixed samples. In the fresh frozen samples only ferritin like iron was observed, whereas in the formalin fixed samples also non-ferritin iron was detected. It seems that in formalin fixed brains, during years, iron is released from ferritin and bound to an iron chelator or formalin.
