Modulation of subventricular zone oligodendrogenesis: a role for hemopressin?

Neural stem cells (NSCs) from the subventricular zone (SVZ) have been indicated as a source of new oligodendrocytes to use in regenerative medicine for myelin pathologies. Indeed, NSCs are multipotent cells that can self-renew and differentiate into all neural cell types of the central nervous system. In normal conditions, SVZ cells are poorly oligodendrogenic, nevertheless their oligodendrogenic potential is boosted following demyelination. Importantly, progressive restriction into the oligodendrocyte fate is specified by extrinsic and intrinsic factors, endocannabinoids being one of these factors. Although a role for endocannabinoids in oligodendrogenesis has already been foreseen, selective agonists and antagonists of cannabinoids receptors produce severe adverse side effects. Herein, we show that hemopressin (Hp),a modulator of CB1 receptors, increased oligodendroglial differentiation in SVZ neural stem/progenitor cell cultures derived from neonatal mice. The original results presented in this work suggest that Hp and derivates may be of potential interest for the development of future strategies to treat demyelinating diseases

Human cerebral organoids and fetal brain tissue share proteomic similarities

The limited access to functional human brain tissue has led to the development of stem cell-based alternative models. The differentiation of human pluripotent stem cells into cerebral organoids with self-organized architecture has created novel opportunities to study the early stages of the human cerebral formation. Here we applied state-of-the-art label-free shotgun proteomics to compare the proteome of stem cell-derived cerebral organoids to the human fetal brain. We identified 3,073 proteins associated with different developmental stages, from neural progenitors to neurons, astrocytes, or oligodendrocytes. The major protein groups are associated with neurogenesis, axon guidance, synaptogenesis, and cortical brain development. Glial cell proteins related to cell growth and maintenance, energy metabolism, cell communication, and signaling were also described. Our data support the variety of cells and neural network functional pathways observed within cell-derived cerebral organoids, confirming their usefulness as an alternative model. The characterization of brain organoid proteome is key to explore, in a dish, atypical and disrupted processes during brain development or neurodevelopmental, neurodegenerative, and neuropsychiatric diseases7CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFINANCIADORA DE ESTUDOS E PROJETOS - FINEPFUNDAÇÃO CARLOS CHAGAS FILHO DE AMPARO À PESQUISA DO ESTADO DO RIO DE JANEIRO - FAPERJFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPNão temNão temNão temNão tem14/21035-0; 16/07332-7; 13/08711-3; 14/10068-4JN, VS-C, and DM-D-S are supported by the São Paulo Research Foundation (FAPESP) grants 14/21035-0, 16/07332-7, 13/08711-3, and 14/10068-4. CS was recipient of a CAPES-FAPERJ Postdoc fellowship. Other funds are provided by the National Council for Scientific and Technological Development (CNPq), the Instituto Nacional de Ciência e Tecnologia de Neurociência Translacional (INCT-INNT), Foundation for Research Support in the State of Rio de Janeiro (FAPERJ), Coordination for the Improvement of Higher Education Personnel (CAPES), Brazilian Funding Authority for Studies and Projects (FINEP), and Brazilian Development Bank (BNDES

Activation of Type 1 Cannabinoid Receptor (CB1R) promotes neurogenesis in murine subventricular zone cell cultures

The endocannabinoid system has been implicated in the modulation of adult neurogenesis. Here, we describe the effect of type 1 cannabinoid receptor (CB1R) activation on self-renewal, proliferation and neuronal differentiation in mouse neonatal subventricular zone (SVZ) stem/progenitor cell cultures. Expression of CB1R was detected in SVZ-derived immature cells (Nestin-positive), neurons and astrocytes. Stimulation of the CB1R by (R)-(+)-Methanandamide (R-m-AEA) increased self-renewal of SVZ cells, as assessed by counting the number of secondary neurospheres and the number of Sox2+/+ cell pairs, an effect blocked by Notch pathway inhibition. Moreover, R-m-AEA treatment for 48 h, increased proliferation as assessed by BrdU incorporation assay, an effect mediated by activation of MAPK-ERK and AKT pathways. Surprisingly, stimulation of CB1R by R-m-AEA also promoted neuronal differentiation (without affecting glial differentiation), at 7 days, as shown by counting the number of NeuN-positive neurons in the cultures. Moreover, by monitoring intracellular calcium concentrations ([Ca2+](i)) in single cells following KCl and histamine stimuli, a method that allows the functional evaluation of neuronal differentiation, we observed an increase in neuronal-like cells. This proneurogenic effect was blocked when SVZ cells were co-incubated with R-m-AEA and the CB1R antagonist AM 251, for 7 days, thus indicating that this effect involves CB1R activation. In accordance with an effect on neuronal differentiation and maturation, R-m-AEA also increased neurite growth, as evaluated by quantifying and measuring the number of MAP2-positive processes. Taken together, these results demonstrate that CB1R activation induces proliferation, self-renewal and neuronal differentiation from mouse neonatal SVZ cell cultures.Fundacao para a Ciencia e a Tecnologia - Portugal [POCTI/SAU-NEU/68465/2006, PTDC/SAU-NEU/104415/2008, PTDC/SAU-NEU/101783/2008, POCTI/SAU-NEU/110838/2009]; Fundacao Calouste Gulbenkian [96542]; Fundacao para a Ciencia e Tecnologiainfo:eu-repo/semantics/publishedVersio

Pharmacological Potential of Flavonoids against Neurotropic Viruses

Flavonoids are a group of natural compounds that have been described in the literature as having anti-inflammatory, antioxidant, and neuroprotective compounds. Although they are considered versatile molecules, little has been discussed about their antiviral activities for neurotropic viruses. Hence, the present study aimed to investigate the pharmacological potential of flavonoids in the face of viruses that can affect the central nervous system (CNS). We carried out research from 2011 to 2021 using the Pubmed platform. The following were excluded: articles not in the English language, letters to editors, review articles and papers that did not include any experimental or clinical tests, and papers that showed antiviral activities against viruses that do not infect human beings. The inclusion criteria were in silico predictions and preclinical pharmacological studies, in vitro, in vivo and ex vivo, and clinical studies with flavonoids, flavonoid fractions and extracts that were active against neurotropic viruses. The search resulted in 205 articles that were sorted per virus type and discussed, considering the most cited antiviral activities. Our investigation shows the latest relevant data about flavonoids that have presented a wide range of actions against viruses that affect the CNS, mainly influenza, hepatitis C and others, such as the coronavirus, enterovirus, and arbovirus. Considering that these molecules present well-known anti-inflammatory and neuroprotective activities, using flavonoids that have demonstrated both neuroprotective and antiviral effects could be viewed as an alternative for therapy in the course of CNS infections

(R)-(+)-Methanandamide promotes the expression of the proneurogenic genes <i>Ngn1</i>.

<p><b>A:</b> Scheme of the protocol. <b>B:</b> Bar graph depicts the fold increase of H3K36m3 recruitment in the promoter region of <i>Ngn1</i> gene quantified by qChIP analysis. <b>C</b>: Bar graph depicts the fold increase of mRNA expression for Ngn1 protein evaluated by qRT-PCR analysis. Data are expressed as mean ± SEM. N = 4–7. *P<0.05, using Dunnett’s test for comparison with control (set to 1). H3K36m3: Histone H3 trimethylated on lysine 36; Ngn1: Neurogenin 1; qChIP: quantitative chromatin immunoprecipitation; qRT-PCR: quantitative real time polymerase chain reaction.</p

(R)-(+)-Methanandamide does not induce glial differentiation in SVZ cultures through CB1R activation.

<p><b>A:</b> Protocol used for studying glial differentiation. <b>B:</b> Western blot analysis of GFAP and Olig2 protein levels in SVZ. Data are expressed as mean ± SEM. N = 4. <b>C:</b> Bar graph depicts the number of GFAP and Olig2-positive cells, expressed as the percentage of total cells <i>per</i> culture. Data are expressed as mean ± SEM. N = 3. <b>D:</b> Representative fluorescent digital images of GFAP-positive cells (green), Olig2-positive cells (red) and Hoechst staining (blue nuclei). Scale bar = 50 µm.</p

(R)-(+)-Methanandamide induces the differentiation of GABAergic neurons and neuritogenesis.

<p><b>A:</b> Schematic representation of the protocol. <b>B:</b> Bar graph depicts the numbers of either VGAT- or TH/βIII tubulin-positive cells, expressed as percentage of total cells. The data are expressed as percentage ± SEM. N = 3. *<i>P</i><0.05 using unpaired Student’s t test for comparison with control. <b>C:</b> Schematic representation of the protocol used for studying neuritogenesis. <b>D:</b> Representative confocal digital images of the GFP (green), MAP2 (red), Hoechst staining (blue), in control cultures and in cultures exposed to R-m-AEA. Scale bar = 20 µm. <b>E:</b> Bar graphs depict (from left to right): total length (µm), number of primary and number of secondary ramifications of MAP2 neurites per cell. N = 3. **P<0.01 using unpaired student’s t test for comparison with control. MAP2: Microtubule-associated protein 2; TH: tyrosine hydroxylase; βIII tubulin: Neuron-specific class III beta-tubulin; VGAT: vesicular GABA transporter.</p

Primary antibodies used for immunocytochemistry.

<p>Primary antibodies used for immunocytochemistry.</p

(R)-(+)-Methanandamide promotes self-renewal.

<p><b>A:</b> Experimental protocol. <b>B:</b> Bar graphs represent the number of primary and secondary neurospheres. Data are expressed as mean ± SEM. N = 6. *P<0.05, **P<0.01 and ***<i>P</i><0.001 using Dunnett’s multiple comparison test, for comparison with control; ^###P<0.001 using Dunnett’s multiple comparison test, for comparison with R-m-AEA. <b>C:</b> Protocol used for studying cell-fate. <b>D:</b> Confocal digital images of cell pairs obtained following (a) the symmetrical division of a SVZ cell into two Sox2+ cells (Sox2+/+), (b) the asymmetrical division into a Sox2+ and a Sox2- progenitor (Sox2+/−) and (c) the symmetrical terminal division into two Sox2- progenitors (Sox2−/−). Scale bars 20 µm. <b>E:</b> Bar graph illustrates the number of each type of cell divisions counted. Data are expressed as the percentage of total cell pairs and are represented as the mean ± SEM. N = 5. *P<0.05 and ***P<0.001 using Bonferroni’s multiple comparison test, for comparison with the respective controls; ^###P<0.001 using Bonferroni’s multiple comparison test, for comparison with the respective R-m-AEA. SOX2: sex determining region Y-box 2.</p