Schwann cells have a limited window of time in which to initiate myelination signaling during early migration in vivo.

The temporal control of mitotic exit of individual Schwann cells (SCs) is essential for radial sorting and peripheral myelination. However, it remains unknown when, during their multiple rounds of division, SCs initiate myelin signaling in vivo. By manipulating SC division during development, we report that when SCs skip their division during migration, but not during radial sorting, they fail to myelinate peripheral axons.

Structural remodeling of the brain cortex and functional recovery following hypoglossal-facial neurorrhaphy in patients with facial paralysis.

Objective: Peripheral nerve injury results in functional alterations of the corresponding active brain areas, which are closely related to functional recovery. Whether such functional plasticity induces relative anatomical structural changes remains to be investigated.

Methods: In this study, we investigated the changes in brain cortical thickness in patients with facial paralysis following neurorrhaphy treatment at different follow-up times.

The walnut tree as a source of progesterone for reproductive control in goats.

Intravaginal sponges impregnated with the progesterone (P4) analogue fluorogestone acetate (FGA) induce synchronous oestrous behaviour and normal ovulatory cycle in goats. To explore alternatives using natural P4 from plants, we developed a method of ethanolic extraction and a specific enzyme immunoassay (EIA) to measure P4 in the different parts of the walnut tree Juglans regia. We found a very high concentration of P4, specifically in the leaves of the three most common French varieties (∼100 mg/kg of DM) but not in flowers, fruits, septa, husk, oil or cake.

The translocator protein 18 kDa (TSPO) ligand etifoxine in an animal model of anxiety: Line- and sex-dependent effects on emotionality, stress reactivity, spine density, oxytocin receptors, steroids, and microbiome composition.

The treatment of stress-related disorders such as anxiety and depression is still challenging. One potential therapeutical option are neurosteroids. Their synthesis is promoted by ligands of the mitochondrial translocator protein 18 kDa (TSPO).

Revisiting the role of sexual hormones in the demyelinated central nervous system.

Sex-related differences characterize multiple sclerosis, an autoimmune, inflammatory and neurodegenerative disease displaying higher incidence in females as well as discrepancies in susceptibility and progression. Besides clinical specificities, molecular and cellular differences related to sex hormones were progressively uncovered improving our understanding of the mechanisms involved in this disabling disease. The most recent findings may give rise to the identification of novel therapeutic perspectives that could meet the urgent need for a treatment preventing the transition from the recurrent- to the progressive form of the disease.

Sonic Hedgehog Is an Early Oligodendrocyte Marker During Remyelination.

Failure of myelin regeneration by oligodendrocytes contributes to progressive decline in many neurological diseases. Here, using in vitro and in vivo rodent models, functional blockade, and mouse brain demyelination, we demonstrate that Sonic hedgehog (Shh) expression in a subset of oligodendrocyte progenitor cells precedes the expression of myelin basic protein (MBP), a major myelin sheath protein. Primary cultures of rodent cortical oligodendrocytes show that Shh mRNA and protein are upregulated during oligodendrocyte maturation before the upregulation of MBP expression.

Tracking myasthenia gravis severity over time: Insights from the French health insurance claims database.

Background And Purpose: Few data are available on the course of myasthenia gravis (MG) regarding disease severity and stability over time in real-world settings. This study used the French National Health Insurance Database (SNDS) to assess markers of disease severity in patients with MG longitudinally.

Methods: All patients with MG-related claims in the SNDS between 2013 and 2020 were identified.

TSPO deficiency promotes the progression of malignant peripheral sheath tumors by regulating the G2/M phase of the cell cycle via CDK1.

Malignant peripheral nerve sheath tumors (MPNSTs) are highly aggressive Schwann cell-derived sarcomas that are sporadic or associated with Neurofibromatosis 1 (NF1) gene mutations. Traditional therapies are usually ineffective for treating MPNSTs, so new targets need to be identified for the treatment of MPNSTs. In the present study, the role of the mitochondrial translocator protein (TSPO) in the regulation of cell proliferation and the cell cycle in MPNSTs was investigated.

Determinants of Timely Access to Recanalization Treatments and Outcomes in Pediatric Ischemic Stroke.

Background: Timely revascularization in acute arterial ischemic stroke (AIS) is paramount for optimal outcomes. However, factors causing treatment delays in pediatric AIS remain understudied. We investigated determinants affecting the time from symptom onset or last-known-well to the start of recanalization treatment in pediatric AIS.

Flow diverter braid deformation following treatment of cerebral aneurysms: incidence, clinical relevance, and potential risk factors.

Background: Although flow diverters (FDs) have benefited from several technical improvements, recently concerns have arisen regarding the braid stability after implantation. Thus, we investigated frequency, predictive factors, and clinical impact of the phenomenon of FD braid deformation (FDBD).

Methods: Consecutive intracranial aneurysms (IAs) treated with various FDs, between January 2018 and July 2023, were reviewed to identify FDBD (defined as the deformation of a FD without any external force applied to it).

A decrease in Fkbp52 alters autophagosome maturation and A152T-tau clearance .

The failure of the autophagy-lysosomal pathway to clear the pathogenic forms of Tau exacerbates the pathogenesis of tauopathies. We have previously shown that the immunophilin FKBP52 interacts both physically and functionally with Tau, and that a decrease in FKBP52 protein levels is associated with Tau deposition in affected human brains. We have also shown that FKBP52 is physiologically present within the lysosomal system in healthy human neurons and that a decrease in FKBP52 expression alters perinuclear lysosomal positioning and Tau clearance during Tau-induced proteotoxic stress .

French National Protocol for diagnosis and care of facioscapulohumeral muscular dystrophy (FSHD).

Facioscapulohumeral muscular dystrophy (FSHD) is one of the most common genetically inherited myopathies in adults. It is characterized by incomplete penetrance and variable expressivity. Typically, FSHD patients display asymmetric weakness of facial, scapular, and humeral muscles that may progress to other muscle groups, particularly the abdominal and lower limb muscles.

Preclinical in vitro and in vivo results of the new silk vista flow diverter with P8RI coating.

Background: Flow diverting stents (FDS) have transformed the treatment of intracranial aneurysms; however, their metallic structure associated with their intra-luminal positioning hamper angiographic and clinical outcomes. Therefore, there is a need to develop FDS with optimized surfaces that reduce thrombogenicity while promoting the healing process and endothelialization.

Methods: P8RI, a peptide mimicking the CD31 protein, was previously developed and grafted onto Silk Vista (SV) FDS.

Creating elastase aneurysms in rabbits: a video primer.

The New Zealand rabbit elastase-induced arterial aneurysm of the right common carotid artery remains a widely used model for assessing the effectiveness and safety of new neuroendovascular devices.1 This model offers a simple and reliable platform for pre-clinical investigations, crucial for comprehending the biological processes underlying aneurysm healing after endovascular treatment.2 Notably, the induced aneurysm exhibits morphological, hemodynamic, and histological characteristics similar to human intracranial aneurysms.

Nestorone (segesterone acetate) effects on neuroregeneration.

Nestorone® (segesterone acetate) is a progestin with a chemical structure closely related to progesterone with high affinity and selectivity for the progesterone receptor without significant interaction with other steroid receptors. It has been developed for female and male contraception and is FDA-approved in a first long-acting contraceptive vaginal system for female contraception. Its safety has been extensively demonstrated in both preclinical and clinical studies for contraceptive indications.

The Smoothened agonist SAG Modulates the Male and Female Peripheral Immune Systems Differently in an Immune Model of Central Nervous System Demyelination.

Both Hedgehog and androgen signaling pathways are known to promote myelin regeneration in the central nervous system. Remarkably, the combined administration of agonists of each pathway revealed their functional cooperation towards higher regeneration in demyelination models in males. Since multiple sclerosis, the most common demyelinating disease, predominates in women, and androgen effects were reported to diverge according to sex, it seemed essential to assess the existence of such cooperation in females.