Mutations upregulating COL4A1 expression lead to PADMAL, a severe early onset ischemic cSVD, distinct from the various phenotypes associated with COL4A1 missense glycine mutations. Ann Neurol 2016;80:741-753.

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Introduction: With an estimated prevalence of up to five percent in the general population, fetal alcohol spectrum disorders (FASD) are the most common neurodevelopmental disorder and more prevalent than autism. Early identification and subsequent early intervention have the potential to improve developmental trajectory of children with FASD. In addition, new research suggests supplementation with choline may ameliorate the developmental impairments associated with prenatal alcohol exposure. Availability of a screening tool with acceptable epidemiologic performance criteria may be clinical useful in identification of young children at increased risk for FASD. In this paper we describe the Early Fetal Alcohol Spectrum Disorder Screening Test (E-FAST) to identify young children at increased risk for an FASD.Methods: We developed the E-FAST dataset from previously published studies, comprised of 281 children under 5 years of age, 180 (64.1%) were diagnosed with FASD and 101 (35.9%) were non-FASD.Analysis: The analysis identified seven useful variables (prenatal alcohol exposure, ADHD (Attention Deficit Hyperactivity Disorder), foster care or adopted, small OFC (occipital frontal circumference), communication impairments, impaired social skills, and cognitive deficits. All variables were categorized as yes/no for ease of use in a screening tool. Risk ratios for each of the seven indicators were estimated using two-way table analyses. Weights for each variable were estimated based on the relative strength of their odds ratios.Results: The average age was 2.7 years of age (S.D. 1.29) and ranged from infant (6.4%) to 4 years old (35.9%). Maternal alcohol use alone had a sensitivity of 0.97, specificity 0.65, and accuracy 0.86. For the combined seven variables, sensitivity was 0.94, specificity 0.74, and accuracy 0.87. Thus, the seven-item E-FAST screen had acceptable epidemiologic screening characteristics.Discussion: In the United States, up to 547 infants with FASD are born each day which far exceeds the capacity of multidisciplinary diagnostic clinics. During routine clinical management of infants and young children the use of an evidence-based screening tool provides a time efficient means to exclude large numbers of young children from further follow-up for FASD. Conversely, a positive screen identifies a smaller number of children at increased risk for FASD requiring more intensive evaluation and follow-up.

Cerebral small vessel disease (SVD) affects the small vessels in the brain and is a leading cause of stroke and dementia. Emerging evidence supports a role of the extracellular matrix (ECM), at the interface between blood and brain, in the progression of SVD pathology but this remains poorly characterized. To address ECM role in SVD, we developed a co-culture model of mural and endothelial cells using human induced pluripotent stem cells from patients with COL4A1/A2 SVD-related mutations. This model revealed that these mutations induce apoptosis, migration defects, ECM remodelling and transcriptome changes in mural cells. Importantly, these mural cell defects exert a detrimental effect on endothelial cells tight junctions through paracrine actions. COL4A1/A2 models also express high levels of matrix metalloproteinases (MMP) and inhibiting MMP activity partially rescues the ECM abnormalities and mural cell phenotypic changes. These data provide a basis for targeting MMP as a therapeutic opportunity in SVD.

AbstractBasement membranes (BMs) provide structural support to tissues and influence cell signaling. Mutations in COL4A1/COL4A2, a major BM component, cause eye, kidney and cerebrovascular disease, including stroke. Common variants in these genes are risk factors for intracerebral hemorrhage in the general population. However, the contribution of the matrix to the disease mechanism(s) and its effects on the biology of cells harboring a collagen IV mutation remain poorly understood. To shed light on this, we engineered controlled microenvironments using polymer biointerfaces coated with ECM proteins laminin or fibronectin (FN), to investigate the cellular phenotype of primary fibroblasts harboring a COL4A2+/G702D mutation. FN nanonetworks assembled on poly(ethyl acrylate) (PEA) induced increased deposition and assembly of collagen IV in COL4A2+/G702D cells, which was associated with reduced ER size and enhanced levels of protein chaperones such as BIP, suggesting increased protein folding capacity of cells. FN nanonetworks on PEA also partially rescued the reduced stiffness of the deposited matrix and cells, and enhanced cell adhesion through β1-mediated signaling and actin-myosin contractility, effectively rescuing some of the cellular phenotypes associated with COL4A1/4A2 mutations. Collectively, these results suggest that biomaterials are able to shape the matrix and cellular phenotype of the COL4A2+/G702D mutation in patient-derived cells.