Project description:Molecular biomarkers for neurodegenerative diseases are critical for advancing diagnosis and therapy. Normal pressure hydrocephalus (NPH) is a neurological disorder characterized by progressive neurodegeneration, gait impairment, urinary incontinence and cognitive decline. In contrast to most other neurodegenerative disorders, NPH symptoms can be improved by the placement of a ventricular shunt that drains excess CSF. A major challenge in NPH management is the identification of patients who benefit from shunt surgery. Here, we perform genome-wide RNA sequencing of extracellular vesicles in CSF of 42 NPH patients, and we identify genes and pathways whose expression levels correlate with gait, urinary or cognitive symptom improvement after shunt surgery. We describe a machine learning algorithm trained on these gene expression profiles to predict shunt surgery response with high accuracy. The transcriptomic signatures we identified may have important implications for improving NPH diagnosis and treatment and for understanding disease aetiology.
Project description:Though congenital hydrocephalus is heritable, it has been linked only to eight genes, one of which is MPDZ. Humans and mice that carry a truncated version of MPDZ incur severe hydrocephalus resulting in acute morbidity and lethality. We show by magnetic resonance imaging that contrast-medium penetrates into the brain ventricles of mice carrying a Mpdz loss-of-function mutation, whereas none is detected in the ventricles of normal mice, implying that the permeability of the choroid plexus epithelial cell monolayer is abnormally high. Comparative proteomic analysis of the cerebrospinal fluid of normal and hydrocephalic mice revealed up to a 53-fold increase in protein concentration, suggesting that transcytosis through the choroid plexus epithelial cells of Mpdz KO mice is substantially higher than in normal mice. These conclusions are supported by ultrastructural evidence, and by immunohistochemistry and cytology data. Our results provide a straightforward and concise explanation for the pathophysiology of Mpdz-linked hydrocephalus.
Project description:Transcriptional profiling of the parietal cortex was performed in postnatal day 22 rats with obstructive hydrocephalus. An intracisternal injection of kaolin was done on postnatal day one, and severe hydrocephalus developed over 3 weeks. Hydrocephalic animals were compared to age-matched saline controls. The goal was to determine the effects of kaolin-induced neonatal hydrocephalus on gene expression. Two-condition experiment: kaolin-induced vs. saline-injected controls. Replicates: 5 treatment samples and 5 saline controls.
Project description:Transcriptional profiling of the parietal cortex was performed in postnatal day 22 rats with obstructive hydrocephalus. An intracisternal injection of kaolin was done on postnatal day one, and severe hydrocephalus developed over 3 weeks. Hydrocephalic animals were compared to age-matched saline controls. The goal was to determine the effects of kaolin-induced neonatal hydrocephalus on gene expression.
Project description:OBJECTIVES: The aim of this study was to determine the prevalence of idiopathic normal-pressure hydrocephalus (iNPH) in elderly persons in a large population-based sample using radiologic and clinical examinations. METHODS: We examined representative elderly populations aged 70 years and older that had undergone neuropsychiatric evaluations and CT of the brain between 1986 and 2000 (n = 1,238). Gait was evaluated by clinical examination and history of walking difficulty. Cognitive function was evaluated with the Mini-Mental State Examination and urinary incontinence by self-report. iNPH was diagnosed in concordance with the American-European iNPH guidelines. Exclusion criteria were history of meningitis, severe head trauma, and subarachnoid hemorrhage. RESULTS: The prevalence of probable iNPH was 0.2% in those aged 70-79 years (n = 2) and 5.9% (n = 24) in those aged 80 years and older, with no difference between men and women. Only 2 of these persons had been treated for iNPH. Hydrocephalic ventricular enlargement, i.e., a CT image consistent with NPH, was found in 56 persons (4.5%). An Evans Index >0.3 was found in 256 (20.7%) and occluded sulci at the high convexity in 67 persons (5.4%). All of these findings were more common in the older age groups. CONCLUSIONS: Many elderly possess clinical and imaging features of iNPH, especially those older than 80 years. The number of persons with iNPH is probably much higher than the number of persons currently treated.
Project description:To explore the genetic cause of a Chinese woman with fetal hydrocephalus X-linked hydrocephalus (XLH), a genetic disorder, has an incidence of 1/30,000 male births. The great proportion of XLH is ascribed to loss of function mutations of L1 cell adhesion molecule gene (L1CAM), but silent mutations in L1CAM with pathogenic potential were rare, and were usually ignored especially in WES detection. In the present study, we describe a novel silent L1CAM mutation in a Chinese pregnant woman reporting continuous five times pregnancies with fetal hydrocephalus. After fetal blood sampling, we found c.453G>T (p.Gly151=) in L1CAM gene of the fetus by whole exome sequencing (WES), RT-PCR of the mRNA from cord blood mononuclear cells and subsequent sequence analysis identified the mutation created a potential 5' splice site consensus sequence, which would result in an in-frame deletion of 72 bp from exon 5 and 24 amino acids of the L1CAM protein. Heterozygous mutations were confirmed in analyzing DNA and mRNA from peripheral blood mononuclear cells of the woman, and, a severe L1 syndrome was confirmed by fetal ultrasound scan and MRI. Our study first indicated c.453G>T (p.Gly151=) in L1CAM could be disease causing for hydrocephalus, which would aid in genetic counseling for the prenatal diagnosis of hydrocephalus. Meanwhile, it suggested some silent mutations detected in WES should not be ignored, splicing predictions of these mutations were necessary.
Project description:Amyloid plaque has been reported in brain biopsies from patients with idiopathic normal-pressure hydrocephalus (iNPH) and proposed as a significant feature of the pathophysiology. Presence of the apolipoprotein E ?4 (APOE ?4) allele is associated with increased risk of Alzheimer's disease (AD).To compare the distribution of APOE genotype in iNPH patients with an age-matched population-based control group and with Alzheimer's disease (AD) patients.APOE genotype frequencies were determined in 77 iNPH patients (50 men and 27 women, mean age 71.7 years) diagnosed with iNPH, a sample of 691 AD patients and 638 age-matched population controls (299 men and 339 women) from the INTERGENE cohort.The APOE distribution did not differ significantly between the iNPH patients and the control population. The per e4-allele odds-ratio (OR) of iNPH was given by OR = 0.90, 95% confidence interval (CI) = (0.50, 1.60) that was considerably smaller than the per-allele OR of AD, OR = 5.34 (4.10, 7.00).The results suggest that the APOE-related risk of AD in patients with iNPH is not higher than in the general population.