SQSTM1 gene as a potential genetic modifier of CADASIL phenotype.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the most common inherited cerebral small vessel disease and is caused by mutations in the NOTCH3 gene. Interestingly, CADASIL patients present a large phenotypic variability even harboring the same pathogenic variant. We describe two CADASIL siblings with a particularly aggressive clinical phenotype characterized by early-onset stroke, gait disturbances and/or dementia, severe emotional dysregulation, and dysexecutive syndrome together with a severe white matter burden on MRI. The genetic analysis revealed the co-occurrence of NOTCH3 (p.Gly420Cys) and SQSTM1 (p.Ser275Phefs*17) pathogenic variants which might worsen the aggressiveness of disease progression in both siblings. Interestingly, to the best of our knowledge, mutations in SQSTM1 gene have never been described in CADASIL patients before. Curiously, both Notch3 and p62 encoded proteins have a key role in the autophagy-lysosomal pathway which is impaired in CADASIL patients. Thus, the contribution of SQSTM1 gene to the clinical heterogeneity of CADASIL patients, in particular for those who develop cognitive impairment or dementia at an early age, is certainly overlooked. Therefore, we advocate expanding the genetic analysis to other genes associated with the phenotype spectrum of CADASIL patients using NGS-customized gene panel.

STROKE34 Study Protocol: A Randomized Controlled Phase IIa Trial of Intra-Arterial CD34+ Cells in Acute Ischemic Stroke.

RATIONALE/AIM: Despite the increasing efficacy of recanalization therapies for acute ischemic stroke, a large number of patients are left with long-term functional impairment, devoid of efficacious treatments. CD34+ cells comprise a subset of bone marrow-derived mononuclear cells with the capacity to promote angiogenesis in ischemic lesions and have shown promising results in observational and in vitro studies. In this study, we aim to assess the efficacy of an autotransplant of CD34+ cells in acute ischemic stroke. SAMPLE SIZE ESTIMATES: 30 patients will be randomized for a power of 90% and alpha of 0.05 to detect a difference in 3 months infarct volume. METHODS AND DESIGN: We will screen 18-80 years old patients with acute ischemic stroke due to occlusion of a middle cerebral artery (MCA) for randomization. Persistent arterial occlusions, contra-indications to magnetic resonance imaging (MRI), premorbid dependency, or other severe diseases will be excluded. Treatment will involve bone marrow aspiration, selection of CD34+ cells, and their administration intra-arterially in the symptomatic MCA by angiography. Patients will be randomized for treatment at 7 (±2) days, 20 (±5 days) or sham procedure, 10 in each group. STUDY OUTCOMES: The primary outcome will be infarct volume in MRI performed at 3 months. Secondary outcomes will include adverse events and multidimensional functional and neurological measures. DISCUSSION/CONCLUSION: STROKE34 is a PROBE design phase IIa clinical trial to assess the efficacy of intra-arterial administration of CD34+ cells 7 and 20 days after acute ischemic stroke. TRIAL REGISTRATION EU CLINICAL TRIALS REGISTER: 2017-002456-88.

Endothelial Progenitor Cells influence acute and subacute stroke hemodynamics.

BACKGROUND: Endothelial Progenitor Cells (EPCs) are a circulating stem cell population with in vivo capacity of promoting angiogenesis after ischemic events. Despite the promising preclinical data, their potential integration with reperfusion therapies and hemodynamic evolution of stroke patients is still unknown. Our aim was to determine the association of EPCs with acute, subacute and chronic hemodynamic features. METHODS: In this prospective study, we included consecutive patients with ages between 18 and 80years and non-lacunar ischemic stroke within the territory of a middle cerebral artery. All patients were subject to hemodynamic evaluation by ultrasound at baseline, seven days and three months. We quantified cerebral blood flow (CBF) and assessed early recanalization and collateral flow. Hemorrhagic transformation was graded in Magnetic Resonance imaging performed at seven days. EPCs were isolated from peripheral venous blood collected in the first 24h and seven days, counted and submitted to functional in vitro tests. RESULTS: We included 45 patients with a median age of 70±10years. The angiogenic and migratory capacities of EPCs were associated with increased collateral flow in the acute stage and day seven CBF, without statistically significant associations with recanalization nor haemorrhagic transformation. The number of EPCs was not associated with any hemodynamic variable. CONCLUSIONS: The functional properties of EPCs are associated with acute and subacute stroke hemodynamics, with no effect on haemorrhagic transformation.

Endothelial progenitor cells enhance blood-brain barrier permeability in subacute stroke.

OBJECTIVE: To study the association among endothelial progenitor cells (EPCs), subacute blood-brain barrier (BBB) permeability, and clinical outcome after ischemic stroke, determining the micro RNAs of EPCs responsible for good clinical outcome. METHODS: We included consecutive patients with nonlacunar acute ischemic strokes in the territory of a middle cerebral artery and ages between 18 and 80 years. Clinical outcome was defined as modified Rankin Scale score at 3 months. Neuroimaging was performed at day 0 and 7 by MRI, including assessment of BBB permeability by dynamic contrast enhancement. EPCs were isolated from peripheral venous blood, quantified, and submitted to in vitro functional tests, including migratory and angiogenic assays. Stroke hemodynamics were evaluated serially by ultrasound. Statistical significance was set at p < 0.05. RESULTS: We included 45 patients; mean age was 70.0 ± 10.0 years. The in vitro functional properties of EPCs were associated with BBB permeability, particularly at day 7. The number of each EPC subset at both timepoints was not associated with BBB permeability. Permeability of BBB at day 7 was independently associated with improved clinical outcome (odds ratio 0.897; 95% confidence interval 0.816-0.986; p = 0.025). The EPCs (CD34+ cell subset) of patients with good clinical outcome showed 24 differentially expressed miRNAs, with a common effect on adherens junction pathway. CONCLUSIONS: The functional properties of EPCs are associated with enhanced subacute permeability of BBB and improved clinical outcome after acute ischemic stroke.