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Apical radial glia comprise the pseudostratified neuroepithelium lining the embryonic lateral ventricles and give rise to the extensive repertoire of pyramidal neuronal subtypes of the neocortex. The establishment of a highly apicobasally polarized radial glial morphology is a mandatory prerequisite for cortical development as it governs neurogenesis, neural migration and the integrity of the ventricular wall. As in all epithelia, cadherin-based adherens junctions (AJs) play an obligate role in the maintenance of radial glial apicobasal polarity and neuroepithelial cohesion. In addition, the assembly of resilient AJs is critical to the integrity of the neuroepithelium which must resist the tensile forces arising from increasing CSF volume and other mechanical stresses associated with the expansion of the ventricles in the embryo and neonate. Junctional instability leads to the collapse of radial glial morphology, disruption of the ventricular surface and cortical lamination defects due to failed neuronal migration. The fidelity of cortical development is therefore dependent on AJ assembly and stability. Mutations in genes known to control radial glial junction formation are causative for a subset of inherited cortical malformations (neuronal heterotopias) as well as perinatal hydrocephalus, reinforcing the concept that radial glial junctions are pivotal determinants of successful corticogenesis. In this review we explore the key animal studies that have revealed important insights into the role of AJs in maintaining apical radial glial morphology and function, and as such, have provided a deeper understanding of the aberrant molecular and cellular processes contributing to debilitating cortical malformations. We highlight the reciprocal interactions between AJs and the epithelial polarity complexes that impose radial glial apicobasal polarity. We also discuss the critical molecular networks promoting AJ assembly in apical radial glia and emphasize the role of the actin cytoskeleton in the stabilization of cadherin adhesion – a crucial factor in buffering the mechanical forces exerted as a consequence of cortical expansion.

Abstract Following our recent discovery of a new scaffold exhibiting significant neurotrophic and neurogenic activities, a structurally tweaked analogue, embodying a 2-oxa-spiro [5.4]decane framework, has been conceptualised and found to be more potent and versatile. It exhibits enhanced neurotrophic and neurogenic action in in vitro, ex vivo and in vivo models and also shows robust neuroprotection in mouse acute cerebral stroke model. The observed attributes are traceable to the predominant activation of the TrkB-PI3K-AKT-CREB pathway. In addition, it also exhibits remarkable anti-neuroinflammatory activity by concurrently down-regulating pro-inflammatory cytokines IL-1α and IL-6, thereby providing a unique molecule with a trinity of neuroactivities, i.e. neurotrophic, neurogenic and anti-inflammatory. The new chemical entity disclosed here has the potential to be advanced as a versatile therapeutic molecule to treat stroke, depression, and possibly other neuropsychiatric disorders associated with attenuated neurotrophic/ neurogenic activity, together with heightened neuroinflammation.

Background: Anti-phospholipid syndrome is a thrombogenic and systemic autoimmune disorder that influences fetal life throughout gestation period. Over expression of tissue factor on the surface of monocyte(s) is reported to be a major causative agent in inducing anti-phospholipid antibody-mediated placental thrombosis and fetal loss in pregnant women. The over expression of tissue factor is proposed to be due to high levels of blood cholesterol and oxidized lipoproteins. Objective: In this study, we report the lipid-lowering property and anti-tissue factor activity of one of the naturally occurring coumarin derivates 6,7-dimethoxycoumarin, found aplenty in Chinese medicinal plant Artemisia scoparia, and its effect on tissue factor mRNA expression in experimental anti-phospholipid syndrome. Materials and Methods: Adult female mice were immunized with cardiolipin and beta-2-glycoprotein-1 to induce experimental anti-phospholipid syndrome. Female mice with high titer of aCL were allowed to mate with male, and the female mice were treated with 6,7-dimethoxycoumarin on a daily dose of 5 mg/kg body weight from day 3 to day 15 of gestation. On day 18 of pregnancy, all the animals were dissected to measure biochemical parameters in blood, and TF mRNA expression levels were measured in placenta. Results: Treatment with 6,7-dimethoxycoumarin significantly reduced the levels of cholesterol and plasma lipids by its potent hypolipidemic property, which eventually reduced the over-expression tissue factor at mRNA levels in placenta. We believe that further studies in animal model would reveal the potential therapeutic properties of 6,7-dimethoxycoumarin against anti-phospholipid syndrome. Conclusion: The 6,7-dimethoxycoumarin is capable to reduce the expression of TF in placenta at the mRNA level and thrombus generation indirectly by its potent anti-TF and anti-oxidant activities. [ABSTRACT FROM AUTHOR]