Investigation of elemental models in senile dementia and depressives using neutron activation analysis

CNS-Related Effects Caused by Vanadium at Realistic Exposure Levels in Humans: A Comprehensive Overview Supplemented with Selected Animal Studies

Neurodegenerative disorders, which are currently incurable diseases of the nervous system, are a constantly growing social concern. They are progressive and lead to gradual degeneration and/or death of nerve cells, resulting in cognitive deterioration or impaired motor functions. New therapies that would ensure better treatment results and contribute to a significant slowdown in the progression of neurodegenerative syndromes are constantly being sought. Vanadium (V), which is an element with a wide range of impacts on the mammalian organism, is at the forefront among the different metals studied for their potential therapeutic use. On the other hand, it is a well-known environmental and occupational pollutant and can exert adverse effects on human health. As a strong pro-oxidant, it can generate oxidative stress involved in neurodegeneration. Although the detrimental effects of vanadium on the CNS are relatively well recognized, the role of this metal in the pathophysiology of various neurological disorders, at realistic exposure levels in humans, is not yet well characterized. Hence, the main goal of this review is to summarize data on the neurological side effects/neurobehavioral alterations in humans, in relation to vanadium exposure, with the focus on the levels of this metal in biological fluids/brain tissues of subjects with some neurodegenerative syndromes. Data collected in the present review indicate that vanadium cannot be excluded as a factor playing a pivotal role in the etiopathogenesis of neurodegenerative illnesses, and point to the need for additional extensive epidemiological studies that will provide more evidence supporting the relationship between vanadium exposure and neurodegeneration in humans. Simultaneously, the reviewed data, clearly showing the environmental impact of vanadium on health, suggest that more attention should be paid to chronic diseases related to vanadium and to the assessment of the dose-response relationship.

Metal changes in CSF and peripheral compartments of parkinsonian patients

BACKGROUND

Involvement of metals in the risk of developing Parkinson's disease (PD) has been suggested. In the present study, concentration of metals in cerebrospinal fluid (CSF), blood, serum, urine and hair of 91 PD patients and 18 controls were compared.

METHODS

Blood and hair were microwave digested, while CSF, serum and urine were water-diluted. Elements quantification was achieved by Inductively Coupled Plasma Atomic Emission Spectrometry and Sector Field Inductively Coupled Plasma Mass Spectrometry.

RESULTS

Some metal imbalances in PD were observed: i), in CSF, lower Fe and Si; ii), in blood, higher Ca, Cu, Fe, Mg and Zn; iii), in serum, lower Al and Cu; iv), in urine, lower Al and Mn, higher Ca and Fe; and v), in hair, lower Fe. The ROC analysis suggested that blood Ca, Fe, Mg and Zn were the best discriminators between PD and controls. In addition, hair Ca and Mg were at least 1.5 times higher in females than in males of patients and controls. A decrement with age of patients in hair and urine Ca and, with less extent, in urine Si was observed. Magnesium concentration in CSF decreased with the duration and severity of the disease. Elements were not influenced by the type of antiparkinsonian therapy.

CONCLUSIONS

Variation in elements with the disease do not exclude their involvement in the neurodegeneration of PD.

Calcium, copper, iron, magnesium, silicon and zinc content of hair in Parkinson's disease

The aetiology of Parkinson's disease (PD) is still unknown, but some hypotheses have focused on the imbalances in body levels of metals as co-factors of risk. To assess whether hair could be a reliable marker of possible changes, calcium (Ca), copper (Cu), iron (Fe), magnesium (Mg), silicon (Si) and zinc (Zn) were determined in hair from 81 patients affected by PD and 17 age-matched controls. Care was taken to eliminate external contamination of the hair by thorough washing. Digestion of the matrix was achieved by an acid-assisted microwave procedure. Quantification of the elements was performed by inductively coupled plasma atomic emission spectrometry. Results indicated significantly lower levels of Fe in the hair of patients (p=0.018) compared with controls. Ca and Mg levels were slightly lower while Zn levels were higher in patients, although these differences were not significant; neither were variations in Cu and Si. Ca and Mg were at least 1.5 times higher in females than in males in both controls and patients. In addition, Ca correlated positively with Mg in both groups and in both sexes (p-value always less than 0.03), and negatively with age in patients (p<0.01). Finally, element levels did not correlate with either the duration or the severity of the disease or with anti-Parkinson treatment.

Elemental concentrations in nigerians with affective disorders using proton-induced X-ray emission

The concentrations of a number of elements are determined in the plasma and erythrocytes of 21 Nigerians (11 females, 10 males) with symptomatic affective disorders (11 depressives, 10 manics) and in 40 normal controls using proton-induced X-ray emission (PIXE) analysis. The study shows that there is significant elevation of plasma K and Zn, as well as the erythrocyte S in the patients relative to the controls. The plasma and erythrocyte Cu, and the erythrocyte P, Ca, Fe, and Zn are significantly lower in the patients compared to the controls. However, the plasma levels of Ca, S, Fe, and Br are similar in both the patients and the controls. Similarly, the concentrations of K, Br, and Rb show no significant difference in the erythrocytes of patients and controls.

Laser microprobe analysis of brain aluminum in Alzheimer's disease

Aluminum (Al) levels were measured in the cytoplasm and nucleus of 241 neurofibrillary tangle (NFT)-bearing neurons, in 217 NFT-free neurons and adjacent neuropil from 7 autopsy-confirmed Alzheimer's disease (AD) patients, and in 316 normal neurons from 5 control subjects, by laser microprobe mass spectrometry. Grand mean Al levels (dry weight basis) in AD samples were 2.93 +/- 1.24 micrograms/gm for NFT-bearing neuron cytoplasm, 3.54 +/- 1.39 micrograms/gm for NFT-bearing neuron nuclei, 2.31 +/- 1.09 micrograms/gm for NFT-free neuron cytoplasm, and 3.23 +/- 1.09 micrograms/gm for NFT-free neuron nuclei. Control values were 1.85 +/- 0.78 micrograms/gm for cytoplasm and 2.01 +/- 0.93 micrograms/gm for nuclei. The differences between corresponding regions of AD NFT-bearing, AD NFT-free, and control neurons were not significant (p > 0.05, analysis of variance). Al levels in neuropil were identical for AD and control samples at 2.16 +/- 0.93 micrograms/gm. In contrast to some literature reports, we found very few (< 2.5%) extremely high Al values (> 20 micrograms/gm, dry weight) on a cellular basis in AD samples. AD neurons did exhibit a higher number of Al values (9.6-14.3%) that were > 3 sigma above the corresponding control means, than did control neurons (1.3-1.6%), indicating that small elevations of Al may exist in patients with AD. Our data suggest that any Al accumulation in patients with AD is small and generalized in both NFT-free and NFT-bearing neurons and that analyses of large bulk brain samples are likely to have AD/control differences masked by the large amount of unaffected neuropil sampled.