zeolites and Alzheimer-Disease

Topics: Aluminum; Aluminum Silicates; Alzheimer Disease; Brain; Down Syndrome; Humans; Renal Dialysis; Silicon

Topics: Aluminum Silicates; Alzheimer Disease; Amyloid beta-Peptides; Humans; Kaolin; Models, Neurological; Plaque, Amyloid

Topics: Aluminum Silicates; Alzheimer Disease; Amyloid beta-Peptides; Humans; In Vitro Techniques; Microscopy, Electron; Tachykinins

A precipitation experiment was performed with human serum to model aluminosilicate formation in brains of patients with Alzheimer disease. Aluminum and (or) silicate ions were added to serum in a 1:2 molar ratio at pH 7.4. Precipitates formed immediately and were left for 24 h at 37 degrees C before filtration. Silicate and aluminosilicate formed precipitates with human serum proteins albumin, transferrin, and IgG. In untreated samples, the IgG/albumin ratio increased slightly compared with the ratio in dried serum. Diethylbarbiturate-washed precipitates had a significantly lower protein content than did untreated ones. The IgG/albumin ratio increased considerably in the sample containing aluminosilicate. We conclude that IgG is the sodium dodecyl sulfate-soluble human protein most firmly bound to the aluminosilicate matrix. From 27Al magic-angle-spinning nuclear magnetic resonance (MAS NMR), a pronounced peak was found at 52.79 ppm and a minor peak at 0.53 ppm, suggesting that 4-coordinated aluminum predominates and that 6-coordinated aluminum is present in a smaller proportion. The 29Si MAS NMR spectrum shows a poorly ordered structure. The aluminosilicate formed also contains the cations Na+ > K+ > Ca2+ > Mg2+ and anions Cl- > PO4(3-). Rather than looking for aluminum toxicity to explain the effects of Alzheimer disease, one should consider that by precipitating such a composite phase, the balance of cations, anions, and proteins in human serum is changing.

Topics: Aluminum; Aluminum Chloride; Aluminum Compounds; Aluminum Silicates; Alzheimer Disease; Anions; Blood Proteins; Brain; Cations; Chemical Precipitation; Chlorides; Electrophoresis, Polyacrylamide Gel; Humans; Immunoglobulin G; Magnetic Resonance Spectroscopy; Serum Albumin; Silicates; Silicic Acid; Spectrophotometry, Infrared; Transferrin; X-Ray Diffraction

By analogy to the etiology of the pneumoconioses, exogenous dust-induced diseases of the lung, and endogenous crystal-induced arthropathies such as gout, it is proposed that Alzheimer's dementia and allied disorders are causally related to the accumulation of fibriform inorganic deposits within the brain. Hence the neonosological term 'Cephaloconiosis'. It is proposed that: 1) either by the extrinsic migration or intrinsic formation and deposition of insoluble and persistent inorganic reactive nidi, the particle-induced generation of tissue-damaging free-radical oxygen metabolites by stimulated brain glial macrophage-type and allied phagocytic cells, provides a rationale for the etiopathogenesis of neurodegenerative processes; 2) the modulation of the injurious oxidative metabolic reaction by micronutrient and pharmacological antioxidant agents is a rational and potentially feasible strategy for future therapeutic clinical investigations.

Topics: Aluminum Silicates; Alzheimer Disease; Antioxidants; Calcium; Free Radicals; Humans; Iron; Models, Biological; Oxidation-Reduction; Vitamins

The occurrence of aluminosilicate deposits within the cerebral plaques in Alzheimer's senile dementia sufferers has prompted further consideration of the possible role of such materials in the aetiology and pathogenesis of the disease. We have monitored the ability of various natural and synthetic model aluminosilicate particulates of differing morphological and chemical composition to stimulate the generation of phagocyte-derived free radical reactive oxygen metabolites (ROM) using an in vitro chemiluminescent technique on purified human blood-derived polymorphonuclear leukocytes (PMN). The results indicate that an enhanced chemiluminescent response is produced by calcium-bearing fibriform particulates. It is proposed that an analogous in vivo particle-induced and phagocyte-mediated oxidative stress could provide a potential pathogenic mechanism in the development of Alzheimer's disease.

Topics: Aluminum Silicates; Alzheimer Disease; Free Radicals; Humans; Kinetics; Luminescent Measurements; Neutrophils; Phagocytosis; Zeolites