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An injection model of preclinical stages of Alzheimer's disease has been reproduced in rats. It was accompanied by the decrease in the latent period of conditioned reflex avoidance, increasing levels of endogenous b-amyloid peptide 1-40 and activation of inflammatory cytokines (IL-1b, TNF-a, IL-6, IL-10) in the cerebral cortex, hippocampus and blood serum of experimental animals. We belive that changes identified at the biochemical level are prerequisite to modulate neuronal functions in rats induced by Ab40_Human administration. The toxic effect of exogenous b-amyloid 1-40 homoaggregates caused intense response of the cytokine system, while its liposomal form caused the soft information signal to the activation of innate immunity.

Recently the studies of Alzheimer's disease have become particularly actual and have attracted scientists from all over the world to this problem as a result of dissemination of this dangerous disorder. The reason for such pathogenesis is not known, but the final image, for the first time obtained on microscopic brain sections from patients with this disease more than a hundred years ago, is well known to clinicists. This is the deposition of Abeta amyloid in the brain tissue of senile plaques and fibrils. Many authors suppose that the deposition of beta-amyloid provokes secondary neuronal changes which are the reason of neuron death. Other authors associate the death of neurons with hyperphosphorylation oftau-proteins which form neurofibrillar coils inside nerve cells and lead to their death. For creation of methods of preclinical diagnostics and effective treatment of Alzheimer's disease novel knowledge is required on the nature of triggering factors of sporadic isoforms of Alzheimer's disease, on cause-effect relationships of phosphorylation of amyloid precursor protein with formation of pathogenic beta-amyloids, on the relationship with these factors of hyperphosphorylation of tau-protein and neuron death. In this review we analyze the papers describing the increasing of intensity of biosynthesis in neurons in normal conditions and under the stress, the possibility of development of energetic unbalanced neurons and activation of their protective systems. Phosphorylation and hyperphosphorylation of tau-proteins is also tightly connected with protective mechanisms of cells and with processes of evacuation of phosphates, adenosine mono-phosphates and pyrophosphates from the region of protein synthesis. Upon long and high intensity of protein synthesis the protective mechanisms are overloaded and the complementarity of metabolitic processes is disturbed. This results in dysfunction of neurons, transport collapse, and neuron death.

The apoA- and apoB-containing lipoprotein (LP) fractions, activity of free and linked forms of lipoprotein lipases (LPL) of liver and extrahepatic tissues, and also activity of lecithin:cholesterol acyltransferase (LCAT) were examined in the blood serum of patients with arterial hypertension, type II diabetes mellitus (DM-II), and metabolic syndrome (MS). Patients with DM-II had the most pronounced changes of all investigated LP fractions compared with healthy persons and patients of other groups examined. Decrease of LCAT activity corresponded to declining level of apoA-containing LP in DM-II and MS. Based on these data obtained we suppose, that one of peculiarities of LP metabolic disorders in the patients is a releasing of a part of lipolitic enzymes, located on the capillary endothelium, into blood flow. Heparin may have an important role in LPL redistribution, as its concentration in blood cells was declined in all the patients.

Contents of lipoproteins (LP), activity of lipoprotein lipase (LP-lipase) and cholesterol esterification activity of blood serum were examined in patients with alcoholism at the periods of intoxication, alcohol abstinence and under conditions of prolonged remission. During remission a general pattern of apoB-containing LP was similar to the period of intoxication. Processes of transformation of this class LP significantly delayed in isolated blood serum in vitro. The magnitude of these changes almost corresponded to the period of intoxication. However activity of free and membrane-bound forms of LP-lipase. A high level of LPHD2a was characteristic for the conditions of intoxication and alcohol abstinence. In the remission the level of all the apoA-containing LP fractions was significantly lower than in the control. Besides, processes of their transformations in vitro were slowed down. Intensity of these changes resembled the period of intoxication. Thus, disorders of LP metabolism pointed out during the period of intoxication and alcohol abstinence do not recovered under conditions of a prolonged remission.

Esterase (LCAT) and lipoprotein lipase (LPL) activities of blood serum, and a range of blood serum lipoproteins (LP) in acute and chronic ethanol intoxication were examined in healthy persons and patients with alcohol abuse. Ethanol inhibited LCAT and LPL activities, and increased apoA-containing LP in blood serum. These changes are considered as a basis for depression of a direct and reverse transportation of cholesterol in blood circulation under the action of ethanol.