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The review highlights recent reports of advances in quantitative neuroproteomics that use new methods to analyze brain functions. Functional neuroproteomics provides new insight into the mechanisms of brain function and neurodegenerative diseases by identifying expressed proteins and their interactions. Analysis of the brain’s proteome made it possible to establish the key proteins that underlie synaptic dysfunction in Alzheimer’s disease and to substantiate the important mechanisms for prognostic and diagnostic biomarkers of the disease.

Experimental and clinical studies provided evidence that astrocytes are inherent components of neural networks. Astrocytes can affect synaptic processes by modulating the activity of neuro- and gliotransmitters. The role of the microglia in the organization of network spaces and the formation of neuroastrocytic domains is considered one of the leading mechanisms of memory and cognitive function. A disorder at the level of synaptic transmission results in the impairment of these processes. For the first time, we present the mechanism by which astrocytes, as components of synaptic processes, become involved in neuropsychic diseases.

—The role of astroglia cells is more complex than the idea that they are an elastic frame that provides structural and metabolic support in the brain. The data of cyto-biochemical and physiological analysis demonstrate that astrocytes are integral elements of neural networks. Astrocytes can affect synaptic processes due to release or modulation of the activity of neurotransmitters. Here, we present ideas on an astrocyte hypothesis, which determines the role of astroglia as a specific management service. Due to the interaction of gliotransmitters with neurons, astrocytes affect the formation of neuronal networks and participate in the regulation of memory and complex behavior in the healthy or diseased brain. The role of astrocytes in organization of network spaces and formation of neuron–astrocyte domains is considered to be one of the physiological mechanisms of memory. We demonstrated the mechanism of the participation of astrocytes in synaptic disintegration and psychoneurological pathology for the first time.

The role of astroglial cells is much more complicated than the notion of an “elastic framework,” which provides structural and metabolic support for brain structures. Astrocytes can affect synaptic processes by participating in the transmission of information by releasing or modulating the activity of neurotransmitters. In vitro and in situ studies revealed a large spectrum of molecules secreted by neuroglial cells. Analysis of the patterns that accompany the secretory mission of astrocytes led to the term “gliotransmission,” which gave rise to a new understanding of plastic regulation of the synaptic function and organization of the neural network, memory, and cognitive processes. The concept of the integrating mission of astroglia also opens up new opportunities for understanding the mechanisms of neurodegenerative diseases and identifying new targets for therapy.

Studies of neural stem cells (NSCs) made substantial adjustments to the basic knowledge of brain development and function. Neurons transformed from NSCs are necessary participants in many physiological processes of the adult brain. The level of neurogenesis, its dynamics, and the number of emerging cells increase with memory stimulation, cognitive processes, social adaptation, reproductive function, and protection from stress. The article considers examples of how experience in communication with an environment of enriched informational background stimulates the formation of new neurons. The analysis makes it possible to consider neurogenesis as a new mechanism to maintain the adaptive plasticity of the adult brain.

Vascular dementia is considered a heterogeneous group of brain diseases in which a cognitive deficit appears because of cerebrovascular disorders caused by chronic hypoperfusion. The pathogenesis includes a complex of processes from changes in cerebral hemodynamics to discordance of neural networks and cognitive disorders. The modern concept of vascular dementia discriminates molecular links of disturbed regulatory and signaling pathways in the brain. The prospective therapeutic targets relate to the regulation of metabolism, signaling molecules of extra- and intracellular control, immune response, apoptosis, and longterm memory. The limitations of current therapeutic agents for dementia can be supplemented by data on pharmacological targets and the opportunity for correction of disturbed processes in the brain.

Endogenous neurogenesis results in the formation of new neural structures that are prerequisites for numerous functions of the adult brain. Neurogenesis is promoted by a large number of regulatory processes when structural and functional support is required. Adaptive neurogenesis may be stimulated by influencing separate signaling elements, such as neuromediators and transduction, transcription, and epigenetic factors. Here, we analyze data on targeted influence on neurogenesis as a novel therapeutic approach. Neurogenesis should be considered in general as a systemic target; by influencing it, it is possible to correct functions disturbed in ischemia, stroke, neurodegenerative disorders, traumas, and psychic pathologies or to perform adaptive support and stimulation of normal physiological functions (memory, cognitive processes, social adaptation, etc.).

A half century of studying the neurogenesis of the adult brain has produced much evidence for an endogenous conversion of neural stem cells. Yet the idea receives increasing criticism, in addition to the many positive comments. Does neurogenesis proceed at a rate sufficiently high for its functional significance? Are new cells capable of integrating into proper brain regions in order to perform a reparative role? How long do new neurons persist in the integration sites, and how significant is their role in the neuronal circuit structure? An organizing function is hypothesized for endogenous adult brain neurogenesis on the basis of current information. One of the main arguments for the hypothesis is the multiplicity of key physiological processes functionally associated with the involvement of new neurons and glial cells: learning, memory, adaptive behavior, protective stress responses, reproductive function, changes in the state of mind, injuries, ischemic and neurodegenerative disorders, etc. The adjustable reprogramming of neuronal precursors and the reparative role of new cells are analyzed. The organizing role of neurogenesis is considered a justified complex process that is important for the function of the adult brain.

Studies of the late 20th century have confirmed the idea that long-term changes in the synaptic system of the human brain form the basis for fixing and maintaining external information. Such phenomena as learning and memory are expressions of these changes at the physiological level. As a result of these studies, the “material” base of these processes was determined as a complex of molecular events that start from the neurotransmitter-synapse interaction and ends with activation of the epigenetic structures of neuronal nucleus. The central event is a coordinated system of signaling pathways, including transduction, transcription, and regulatory (neurotrophic) proteins. Consistent temporal and spatial activations of these structures are the biochemical basis for memory formation and cognitive functions. Synaptic plasticity as a primary mechanism of memory and a multilevel system of signal molecule regulation constitute the essence of organizing different types of memory. The disturbance of neurochemical mechanisms is an initial cause of cognitive dysfunction and psychopathology. At the same time, signal molecules can be considered specific targets for the correction of these states.

The dogma that the adult mammalian brain does not generate new neurons has been reconsidered as a result of the discoveries of recent decades. In the adult brain, neurogenesis is determined as a process of the transformation of neural stem cells into mature functional neurons. Adult neurogenesis is a developmental process proceeding within the mature nervous system and represents a striking form of neural plasticity, learning and memory functions in the adult brain. This process is dynamically regulated by both intrinsic cues of state-specific cell differentiation and extrinsic neural niche signals. Adult brain neurogenesis opens possibilities for understanding brain functions (such as memory) and working out novel therapeutic strategies that use neural stem cells to repair injured brain structures.

Studies in the second half of the 20th century accumulated evidence that refuted the dogma that “nervous cells are not restored.” During the entire life of the body, neural stem cells or progenitors are continuously transformed and new structures, such as neurons, astrocytes, and oligodendrocytes, are integrated. Regulation of this process is complex and invariably interrelated with the adaptive capacities of the healthy, aging, and disabled brain. In this review, on the basis of a large body of data, we postulate the hypothesis of the adaptive mission of neurogenesis in the adult brain. We present the data of experimental and clinical studies as a scheme of phase transformation of brain stem cells and their role in adaptive processes. We summarize the data on the role of newborn neurons in the pathology of the ischemic, neurodegenerative, and aging processes. An important role is performed by signaling molecules, which are important integrators of brain adaptive functions. The scheme of the mechanisms of neurogenesis becomes clearer when one takes the large number of various signaling molecules involved in this regulation into account. Several levels of signaling may be noted, such as (a) neurotrophins and growth factors; (b) molecules of the transduction cascade; (c) molecules of transcription of a signal to the replication apparatus of the cell; and (d) epigenetic factors, which govern signaling polyphony. The new and practically important concept that is elaborated here is the thesis that these molecules may be used as “targets” for directed pharmacological therapeutic influence.

The review is devoted to pharmacological effects and clinical effectiveness of one of the "oldest" neurocytoprotective drugs cerebrolysin. Experimental data that have revealed molecular mechanisms of the drug action as well as the results of clinical trials demonstrating the efficacy of cerebrolysin in the treatment of acute and chronic brain ischemia, Alzheimer's disease, moderate and mild cognitive disorders are described in details. It has been concluded that the efficacy o this drug has been supported by fundamental research, using animal models and cell cultures, and multiple clinical trials in patients with different pathologies.

At present, epigenetic regulation is considered as a dynamic mechanism by means of which cells realize adaptive response to signals from both the inner medium and environment. DNA methylation, as bidirectional balance of the activity of histone-acetylation and -deacetylation (HDAC) enzymes, determines the conformation of chromatin thus playing the main role in "appropriate" gene expression. HDACs represent emerging therapeutic targets in the context of treating various forms of neurological and mental illness. A wide range of brain diseases are associated with imbalance between protein acetylation levels and tran- scriptional dysfunctions. Increasing evidence supports the notion that histone hypoacetylation and transcriptional dysfunction are involved in a large number of neurodegenerative conditions in vivo and in vitro. Histone deacetylase inhibitors (HDACIs) that affect the acetylation status of histones and other important cellular proteins--have been recognized as potentially useful therapeutic means for a broad range of human disorders. This review summarizes the current state of development of HDACIs based therapeutics and their application for the treatment of human brain neurodegenerative, ischemic, and cognitive pathologies. Treatment with various HDACIs can correct these deficiencies and has emerged as a promising new strategy for therapeutic intervention based on the experimental search and clinical testing of HDACIs representing compounds of various classes.

Neurotrophins belong to a family of polypeptides that exert control over many aspects of the survival, development, and functioning of structures within the central and peripheral nervous system. Neurotrophins, the nerve growth factor (NGF), the brain derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3), as well as extracellular tyrosine kinase receptors (TrkA, TrkB, and TrkC) are specific targets for therapeutic intervention during different diseases. All these neurotrophins also bind to the p75 receptor, which has many functions depending on the type of cell where it is present. The diversity of neurotrophin effects is determined by ligand-receptor binding and the type of signaling responses that are specific for this interaction. NGF and other neurotrophins are involved in many pathological conditions. It has been shown that an insufficient level of neurotrophins in certain brain structures may be not only an initial cause of Alzheimer’s disease but also may be typical for cerebrovascular dysfunction, brain trauma, cognitive impairments, etc. The therapeutic potential of neurotrophins has been shown in many studies in the last decade but the effectiveness of neurotrophic therapy is limited by the poor diffusion of molecules across the blood-brain barrier and toxic adverse effects. The solution to this problem may be the creation of minipeptides and peptidomimetics that affect the activity of tyrosine-kinase receptors. Some of these structures are combinations of cyclic pentapeptides that facilitate interaction with Trk receptors and exert neuroprotective activity. In this review, we discuss the clinical and experimental data on the results of an alternative strategy that uses these peptidomimetics. These compounds comprise a new group of perspective agents in the therapy of neurodegenerative disorders.

The results of recent publications on a role of stem cells in the processes of neurogenesis, adaptation and neuroplasticity are summarized. An aim of the paper was to present evidence for a possibility of development and regeneration of cellular elements in the adult brain in normality and pathology. The latter was driven by the discussion of the studies on Alzheimer's disease, Parkinson's disease, schizophrenia and affective disorders. Pharmacological effects on the neurogenesis and perspectives of this research are reviewed.

The aim of this study was to investigate how blocking functional endothelin-converting enzyme activity may offer a new approach to inhibition of changes in pulmonary vessels reactivity due to development of hypoxia-induced pulmonary arterial hypertension in rats. This data shows that treatment with endothelin-converting enzyme blocker PP36 significantly reduced pathological changes due to hypoxia-induced pulmonary hypertension. One of the reasons may be the increased production and role of nitric oxide in pulmonary artery tone.

A new endothelin-converting enzyme inhibitor PP-35 including Nα-benzylsuccinyl group and Leu-Trp-OH dipeptide is synthesized. Similarly to phosphoramidon substance PP-35 abolishes elevation of systemic blood pressure and heart rate decrease in normotensive rats in response to bolus injection of big endothelin-1. Hemodynamic responses to endothelin-1 remain unchanged.

Neurotrophic and growth factors are major subgroups of polypeptides that are synthesized naturally and characterized by the following effects: neuronal differentiation, survey of nerve cell functional integrity, protection against degeneration and lesions, which maintain nerve cells alive. Neurotrophic and growth factors increase the resistance of neuronal tissue to the noxious influence such as hypoxia, exitotoxicity, trauma, stress injury, hypoglycemia, etc. Neurotrophic and growth factors are important in the synaptic plastivcity, activity of learning and cognitive proecesses, regulation of depressive and anxiogenic states. Analysis of clinical and experimental data suggested tha main role of neurotrophins and growth factors in the pathogenesis of ischemic and neurodegenerative brain processes. Some factors are considered as specific markers or targets for concrete diseases; but for any other factors the protective function and therapeutically opportunity for treatment of some pathologies have been revealed. There is some evidence for antiapoptic effects of neurotrophic and growth factors as a basic principle for their neuroprotective function.

The paper summarises the comprehensive concept on main groups of chemical substances and on their diverse regulatory function in the brain. Neurotransmitters, neuropeptides, neurotrophic and growth factors, and cytokines are considered as many-storied, integral structure. The proper analysis of ischemic and neurodegenerative brain disturbances evidently demonstrates the active participation of basic families of these chemical regulators at all stages of the pathogenesis. The main theoretical positions involving these regulatory substances in the control of normal and pathological situations include: (a) dogma on the imbalance of chemical regulators, as the initial pathogenetic principle; (b) genetically heterogeneity of brain structures, which demonstrate selective vulnerability or, to the contrary, steadiness for damaging exposure. As a general principle for increasing number of clinical and experimental pathologies, the induction of apoptic cascade processes is postulated; their "normal" biological function in nervous tissues is a key factor for development of majority of brain diseases.

Multiple neurochemical mechanisms (neurotransmitters, regulatory peptides, neurotrophic growth factors, and proteins of the signaling transducer systems) maintain the integrity of nerve cell circuits, facilitate the responses to environmental demands and promote the recovery of a function after injury. The recent application of modern approaches of molecular and cellular biology to the problem of "diseased (bad) brain" reveals a remarkable capacity within brain cells for adaptation to aging and resistance to a disease. The death of neurons in different neurological disorders involves apoptotic biochemical cascades leading to mitochondrial alterations, upstream pro-apoptotic effectors, and caspases activation. At the cellular level, neuronal apoptosis in ischemic and neurodegenerative disorders may be triggered by oxidative stress, mitochondrial compromise and disruption of calcium homeostasis. Both genetic and environmental factors, and the aging process itself, contribute to initiation of such neuronal apoptosis. Neuroprotective (antiapoptotic) signal pathways involving neurotrophic factors, neuropeptides, and mediators able to counteract with effects of aging and genetic predisposition in experimental models and clinical events of neuro-destructive disorders.

Phenomenology of neurodegenerative disorders of any genesis corresponds to modern concepts of apoptosis as a morphobiochemical mechanism for programmed death of certain nervous cell populations. Neuroapoptosis is assumed to be a basic cause of all kind of neuropathology. Neuropeptides synthesized in certain brain regions and neurotrophic growth factors playing an important role in brain function control get involved in neurodestructive process realization as pro- or antiapoptotic components. On the basis of above concepts it is suggested that therapeutic efficacy of cerebrolysin, successfully used for therapy of wide spectrum of ischemic, neurodegenerative and other brain pathologies lies in inhibiting influence on apoptosis-dependent processes in the nervous cell. This medication including a neuropeptide and neurotrophic factors complex has many targets, which may be used for neuroapoptosis correction on different stages of pathological process.

The development of arterial hypertension is accompanied by impairment of the normal ratio of the "ACE-depending" and of the sympathetic nervous system, correlates with the action on the main pharmacological "targets": I-I-imidazoline receptors (moxonidine) or the ACE activity (enalapril). The aim of the present investigation was to determine the hypotensive and metabolic effects of moxonidine and enalapril depending on the basal ACE activity in patients with arterial hypertension, complicated with the metabolic syndrome. Effectiveness of moxonidine and enalapril administration (during 24 weeks) depended on the basal ACE activity in the hypertensive patients: (a) in the group of patients with low basal ACE activity moxonidine very effectively decreased systolic and diastolic blood pressure, compared with the group of patients with high basal ACE activity; (b) influence of enalapril on the level of arterial blood pressure was more pronounced with high basal ACE activity.choosing a hypotensive treatment for patients with the metabolic syndrome, it is advisable to take into account the basal ACE activity levels.

Experiments on chronically instrumented Wistar rats demonstrated that 15 mm microsphere embolization of coronary arteries led to a significant decrease in the systemic (APsyst) and maximal left ventricular systolic pressures (LVSPmax) to 10.1 and 21.1%, respectively (p0.05). To evaluate the role of endothelin in this pathology, the inhibitor of endothelin-converting enzyme (ECE), PP-36, was used. PP-36 abolished hemodynamic changes caused by embolization after 4 days per os treatment (starting 2 days before surgical procedure). Dobutamine test revealed marked decrease of LVSPmax and +dP/dtmax responses in the embolized versus sham operated animals. PP-36 normalized ischemical heart response to beta-adrenergic stimulation. Maximal APsyst and LVSPmax increases were observed in embolized rats. PP-36 abolished this effect and led to parallel rising reaction to aminoguanidin in embolized (APsyst: +12.4 +/- 1.6 vs. +6.8 +/- 2.3 mmHg, p0.05) as well as in sham operated rats (APsyst: +8.5 +/- 1.1 vs. +5.6 +/- 0.7 mmHg, p0.05). Thus, the present research showed the possibility to correct ischemical heart disturbance by using a new ECE inhibitor, PP-36. One possible mechanism of this drugs action may include systemic or myocardial changes in NO contribution to the maintenance of normal arterial pressure.

A rapidly growing body of data support the concept of endothelin as a paracrine acting endothelial regulators. The system of endothelin peptides--their chemical structure, physiological activity and role in cardiovascular pathological processes are reviewed. Molecular specificity, isoforms, and physicochemical parameters of the endothelin-converting enzyme (ECE) characterize this novel metalloproteinase as important regulator, that catalyses final step in the biosynthesis of endothelins. The role of the general endothelial system for various cardiovascular pathological states, including congestive heart failure and myocardial infarction, arterial hypertension, atherosclerotic vascular diseases is discussed. Therapeutic approaches with some endothelin receptor antagonists and ECE inhibitors are discussed, and endothelin system therefore represents a likely target for the development for the novel pharmaceutical agents.

Inhibition of bovine lung and testicular angiotensin-converting enzyme (ACE) by some well-known ACE inhibitors (lisinopril, captopril, enalapril), new substances (Nalpha-carboxyalkyl dipeptides PP-09, PP-35, and PP-36), and phosphoramidon was investigated using Cbz-Phe-His-Leu and FA-Phe-Phe-Arg (C-terminal analogs of angiotensin I and bradykinin, respectively) as the substrates. The somatic (two domains) and testicular (single domain) isoenzymes demonstrated different kinetic parameters for hydrolysis of these substrates. All of the inhibitors were competitive inhibitors of both ACE isoforms, and the Ki values were substrate-independent. The relative potencies of the inhibitors for both enzymes were: lisinoprilcaptoprilPP-09enalaprilPP-36PP-35phosphoramidon. The inhibition efficiency of PP-09 was comparable with those of the well-known ACE inhibitors. Captopril was more effectively bound to the somatic ACE (Ki = 0.5 nM) than to the testicular isoform (Ki = 6.5 nM).

The data obtained suggest a potential mechanism that may account for the selective control of adrenaline and noradrenaline release from adrenal chromaffin cells. Some neuropeptides seem to affect in a different way the release from A- and NA-adrenal cells by means of regulating a set of cytochemical events: specific reception of cholinergic transmitters, expression of the second messenger system including cGMP and changes in Ca channels activity, changes in the catecholamine biosynthesis in adrenal chromaffin cells. Modulating function of substance P, endothelins, PACAP, and ANF, is discussed.

The system of endothelin peptides and their structure, biological activity, and role in physiological and pathological processes are reviewed with emphasis on endothelin-converting enzyme (ECE), which catalyzes the terminal processing of endothelin. Molecular specificity, structure, isoforms, physicochemical characteristics, substrate preference, and tissue localization characterize this enzyme as a novel and highly important metalloendopeptidase. The role of ECE in pathological processes and data on inhibitors of the enzyme which can have medical implication are summarized.

The effect of N(alpha)-carboxyalkylated dipeptides on angiotensin-converting and kinin-degrading activity of angiotensin-converting enzyme (ACE, dipeptidyl carboxypeptidase) was studied. These inhibitors selectively affected ACE-induced hydrolysis of angiotensin I-like and bradykinin-like (hippuryl-His-Leu and hippuryl-Phe-Arg, respectively) substrates in microsomal fractions of rat lungs and kidneys and rat blood serum. The inhibition constants of both types of activity were determined for these enzyme preparations and also for ACE from porcine seminal fluid and highly purified ACE from porcine lung. In all cases high inhibition selectivity of angiotensin-generating and kininase activities of ACE was found.

New fluorogenic substrate of carboxypeptidase H, Cum-Phe-Ala-Arg-OH, is hydrolyzed by this enzyme to give Cum-Phe-Ala-OH, which is completely extracted by chloroform from the reaction mixture and whose fluorescence increases remarkably by the presence of triethylamine. When the hydrolysis of the novel substrate is compared with Dns-Phe-Ala-Arg-OH, the former has Km twice as low (30 microM) and kcat four times as high (5.8 s-1). Activation of the enzyme by Co2+ in reactions with the two substrates was also studied. The novel substrate is useful for the enzyme's assay in homogenates of various animal tissues.

Muricidal and non-muricidal Wistar rats were studied regarding the changes of the body weight, the volume of the liquid intake, the sensitivity threshold to electrical shock, horizontal and vertical locomotor activity during 40-days period of 20% ethanol consumption. The transition to the situation of "choice" (water and/or ethanol) was accompanied by a division of the animals into two groups: "water preferring" and "ethanol-preferring" rats. The angiotensin-converting enzyme and enkephalin-forming carboxypeptidase H activity in different brain regions, hypophysis and peripheral tissues, were defined. The results allow one to conclude that neurochemical mechanisms underlying aggressive behavior (muricidity) and alcohol addiction have originally distinct nature.

Activities of enkephalin- and angiotensin II-forming enzymes (carboxypeptidase H and angiotensin-converting enzyme, ACE) were changed in different brain regions and peripheral tissues of rats with various alcohol motivation. The carboxypeptidase H activity was elevated in midbrain, striatum, hypophysis and adrenal glands, while the ACE activity was increased in hypophysis and striatum. The ACE activity was decreased two-fold in thalamo-hypothalamic region of ethanol-preferring rats.

Consistent study of stages and history of discovery of regulatory peptides (RP) as a new class of multifunctional endogenic regulators puts forward some actual problems. A question what new notions on the manner of control of physiological functions have been introduced by RP investigation is considered. Two historical tendencies in the RP studies are estimated. A conception on peptides as multifunctional and colocated factors of neurohumoral regulation of organism was opposed to the idea of "single" substance--a regulator of "unique" function. In this connection a conception of peptide-regulatory continuum is considered and the author postulated the principle "what--where--when" as the main rule of RP well-regulated action. The statement on tissue (regional) specificity of the biogenesis processes of different RP as molecular basis of their regulatory function is grounded.

The results show that during long-term immunization of rats against conjugates of angiotensin II with bovine serum albumin definite age dynamics of immune response have been observed. It was shown that the changes of physiological readings were correlated with growing of antibodies titer against angiotensin II, accordingly, as the immune response was lower, these readings return to the initial level.

An attempt to treat critically the key methodological positions of modern biochemistry, primarily, the medical biochemistry with reference to the physiologic, pathophysiologic and clinical tasks is made. The author puts forward questions: 1) if it is possible to apply traditional approaches (principles) of biochemical investigation developed on purified systems to the whole organism systems in situ and etc.; 2) if it coincides the methodical approaches of biochemistry on the one hand and physiology (pathophysiology)--on the other one, considering the mechanisms of disease development and correspondingly the assessment and choice of therapeutic methods; 3) if there exists a necessity to create a unite methodology of biochemical and physiologic knowledge as a basis of modern medical science as a whole. Some examples showing the possible ways of new methodic consideration of traditional conceptions of in vitro biochemistry are given.