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The contribution of astrocytes and microglia to the regulation of neuroplasticity or neurovascular unit (NVU) is based on the coordinated secretion of gliotransmitters and cytokines and the release and uptake of metabolites. Blood-brain barrier (BBB) integrity and angiogenesis are influenced by perivascular cells contacting with the abluminal side of brain microvessel endothelial cells (pericytes, astrocytes) or by immune cells existing (microglia) or invading the NVU (macrophages) under pathologic conditions. The release of gliotransmitters or cytokines by activated astroglial and microglial cells is provided by distinct mechanisms, affects intercellular communication, and results in the establishment of microenvironment controlling BBB permeability and neuroinflammation. Glial glutamate transporters and connexin and pannexin hemichannels working in the tight functional coupling with the purinergic system serve as promising molecular targets for manipulating the intercellular communications that control BBB permeability in brain pathologies associated with excessive angiogenesis, cerebrovascular remodeling, and BBB-mediated neuroinflammation. Substantial progress in deciphering the molecular mechanisms underlying the (patho)physiology of perivascular glia provides promising approaches to novel clinically relevant therapies for brain disorders. The present review summarizes the current understandings on the secretory machinery expressed in glial cells (glutamate transporters, connexin and pannexin hemichannels, exocytosis mechanisms, membrane-derived microvesicles, and inflammasomes) and the role of secreted gliotransmitters and cytokines in the regulation of NVU and BBB permeability in (patho)physiologic conditions.

Adipose tissue is recognized as an important organ with metabolic, regulatory, and plastic roles. Adipose tissue-derived stem cells (ASCs) with self-renewal properties localize in the stromal vascular fraction (SVF) being present in a vascular niche, thereby, contributing to local regulation of angiogenesis and vessel remodeling. In the past decades, ASCs have attracted much attention from biologists and bioengineers, particularly, because of their multilineage differentiation potential, strong proliferation, and migration abilities in vitro and high resistance to oxidative stress and senescence. Current data suggest that the SVF serves as an important source of endothelial progenitors, endothelial cells, and pericytes, thereby, contributing to vessel remodeling and growth. In addition, ASCs demonstrate intriguing metabolic and interlineage plasticity, which makes them good candidates for creating regenerative therapeutic protocols, in vitro tissue models and microphysiological systems, and tissue-on-chip devices for diagnostic and regeneration-supporting purposes. This review covers recent achievements in understanding the metabolic activity within the SVF niches (lactate and NAD+ metabolism), which is critical for maintaining the pool of ASCs, and discloses their pro-angiogenic potential, particularly, in the complex therapy of cardiovascular and cerebrovascular diseases.

Acute respiratory infections (ARI) still represent a big challenge for paediatricians, especially in those children defined as "ailed" as they are more susceptible to such kinds of disease. In this paediatric population, the immune system is still under-developed with an evident alteration in cytokine levels. A clinical study was carried out in 5 sites in Russia with the intention to enroll children particularly susceptible to contract respiratory infections (defined as "ailing"), assigning them to a treatment group with pidotimod in comparison with a control group, treating them for 30 days and observing the reduction in the number of ARI episodes throughout the follow-up period (6 months). Moreover, changes in serum immunological markers were evaluated at baseline and 30 days after treatment discontinuation. One hundred and fifty-seven ailing children were enrolled and assigned to two arms: a main pidotimod treatment group or a control group. The percentage of incidence of ARIs in the observation period at three different time points was statistically significant (p < 0.05). At the end of the follow-up period (after 6 months), ARIs had developed in 72 children (92.3%) in the main group and in 79 patients (100%) in the control group. Concerning changes of the immunological markers, the treatment group showed a better profile of normalization compared to the control group. The 30-day pidotimod therapy course led to improvement/reduction in the rate of acute respiratory infection recurrence in ailing children within a 3-month period, with a quick elimination of symptoms and signs of infection and, as a result, a faster recovery. The normalisation of the content of the pro-inflammatory cytokine interleukin-8 confirmed the immune-modulatory effect of the investigational drug, underlying its prophylactic effect.

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