beta-NAD(+) is as abundant as ATP in neuronal cells. beta-NAD(+) functions not only as a coenzyme but also as a substrate. beta-NAD(+)-utilizing enzymes are involved in signal transduction. We focus on ADP-ribosyl cyclase/CD38 which synthesizes cyclic ADP-ribose (cADPR), a universal Ca(2+) mobilizer from intracellular stores, from beta-NAD(+). cADPR acts through activation/modulation of ryanodine receptor Ca(2+) releasing Ca(2+) channels. cADPR synthesis in neuronal cells is stimulated or modulated via different pathways and various factors. Subtype-specific coupling of various neurotransmitter receptors with ADP-ribosyl cyclase confirms the involvement of the enzyme in signal transduction in neurons and glial cells. Moreover, cADPR/CD38 is critical in oxytocin release from the hypothalamic cell dendrites and nerve terminals in the posterior pituitary. Therefore, it is possible that pharmacological manipulation of intracellular cADPR levels through ADP-ribosyl cyclase activity or synthetic cADPR analogues may provide new therapeutic opportunities for treatment of neurodevelopmental disorders.

The excitation/inhibition (E/I) balance controls the synaptic inputs to prevent the inappropriate responses of neurons to input strength, and is required to restore the initial pattern of network activity. Various neurotransmitters affect synaptic plasticity within neural networks via the modulation of neuronal E/I balance in the developing and adult brain. Less is known about the role of E/I balance in the control of the development of the neural stem and progenitor cells in the course of neurogenesis and gliogenesis. Recent findings suggest that neural stem and progenitor cells appear to be the target for the action of GABA within the neurogenic or oligovascular niches. The same might be true for the role of neuropeptides (i.e. oxytocin) in neurogenic niches. This review covers current understanding of the role of E/I balance in the regulation of neuroplasticity associated with social behavior in normal brain, and in neurodevelopmental and neurodegenerative diseases. Further studies are required to decipher the GABA-mediated regulation of postnatal neurogenesis and synaptic integration of newly-born neurons as a potential target for the treatment of brain diseases.

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Blood-brain barrier (BBB) modeling in vitro is a huge area of research covering study of intercellular communications and development of BBB, establishment of specific properties that provide controlled permeability of the barrier. Current approaches in designing new BBB models include development of new (bio) scaffolds supporting barriergenesis/angiogenesis and BBB integrity; use of methods enabling modulation of BBB permeability; application of modern analytical techniques for screening the transfer of metabolites, bio-macromolecules, selected drug candidates and drug delivery systems; establishment of 3D models; application of microfluidic technologies; reconstruction of microphysiological systems with the barrier constituents. Acceptance of idea that BBB in vitro models should resemble real functional activity of the barrier in different periods of ontogenesis and in different (patho) physiological conditions leads to proposal that establishment of BBB in vitro model with alterations specific for aging brain is one of current challenges in neurosciences and bioengineering. Vascular dysfunction in the aging brain often associates with leaky BBB, alterations in perivascular microenvironment, neuroinflammation, perturbed neuronal and astroglial activity within the neurovascular unit, impairments in neurogenic niches where microvascular scaffold plays a key regulatory role. The review article is focused on aging-related alterations in BBB and current approaches to development of “aging” BBB models in vitro.

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NAD + is as abundant as ATP in neuronal cells. NAD + functions not only as a coenzyme but also as a substrate. NAD + metabolism in neuronal cells is tightly controlled under physiological conditions, since NAD + has a great impact on functional activity of neurons upon stimulation. NAD + -utilizing enzymes is involved in signal transduction. We focus on ADP-ribosyl cyclase/CD38 which synthesizes cyclic ADP-ribose (cADPR), a Ca 2+ mobilizing messenger. Structural analysis defined the active site of the enzyme. ADP-ribosyl cyclase associated with CD38 was detected in the central nervous system (CNS) where its activity and expression were developmentally regulated. CD38 has been reported to have different subcellular locations either in neurons or in glial cells, suggesting multiple roles. cADPR, acts as a universal calcium mobilizer from intracellular stores independently from inositol trisphosphate which acts through activation/modulation of ryanodine receptor channels involving FKBP12.6. cADPR was also involved in the regulation of some potassium currents in synaptic activity. cADPR synthesis in neuronal cells is stimulated or modulated via different pathways and various factors. Subtype-specific coupling of various neurotransmitter receptors with ADP-ribosyl cyclase confirms the involvement of the enzyme in signal transduction in neurons and glial cells. Therefore, it is possible that pharmacological manipulation of intracellular cADPR levels through ADP-ribosyl cyclase activity or expression, in the CNS may provide new therapeutic opportunities for treatment of neurological disorders.

We studied the role of disturbances in cell Ca(2+) homeostasis in plasma membrane blebbing and death of thymocytes. Capacitance Ca(2+) channels of the plasma membrane and intracellular Ca(2+) stores are involved in the induction and progression of changes in the membrane and cytoskeleton and apoptosis induced by acrylonitrile.

ATP activity in mouse bone marrow cells was in vitro estimated by expression of phosphatidylserine on the outer membrane surface using FITC-labeled annexin. ATP induced apoptosis in bone marrow cells. Purinergic receptor antagonists PPADS and suramin modulated the apoptotic effect of ATP on hemopoietic cells. Acute and subacute administration of doxorubicin, an inductor of oxidative burst, decreased cell sensitivity to ATP and abolished its apoptotic effect.