Li A.,MassGeneral Institute for Neurodegenerative Diseases |
Ahsen O.O.,Massachusetts Institute of Technology |
Liu J.J.,Massachusetts Institute of Technology |
Du C.,Tufts University |
And 9 more authors.
Human Molecular Genetics | Year: 2013
The SRY-relatedHMG-box 5 (SOX5) gene encodes amember of theSOXfamily of transcription factors. Recently, genome-wide association studies have implicated SOX5 as a candidate gene for susceptibility to four cardiacrelated endophenotypes: higher resting heart rate (HR), the electrocardiographic PR interval, atrial fibrillation and left ventricular mass. We have determined that human SOX5 has a highly conserved Drosophila ortholog, Sox102F, and have employed transgenic Drosophila models to quantitatively measure cardiac function in adult flies. For this purpose, we have developed a high-speed and ultrahigh-resolution optical coherence tomography imaging system, which enables rapid cross-sectional imaging of the heart tube over various cardiac cycles for the measurement of cardiac structural and dynamical parameters such as HR, dimensions and areas of heart chambers, cardiac wall thickness and wall velocities. We have found that the silencing of Sox102Fresulted in a significant decrease inHR, heartchambersizeandcardiac wall velocities, anda significant increase in cardiac wall thickness that was accompanied by disrupted myofibril structure in adult flies. In addition, the silencing of Sox102F in the wing led to increased L2, L3 and wing marginal veins and increased and disorganized expression of wingless, the central component of the Wnt signaling pathway. Collectively, the silencing of Sox102F resulted in severe cardiac dysfunction and structural defects with disrupted Wnt signaling transduction in flies. This implicates an important functional role for SOX5 in heart and suggests that the alterations in SOX5 levels may contribute to the pathogenesis of multiple cardiac diseases or traits. © The Author 2013. Published by Oxford University Press. All rights reserved.
Serrano-Pozo A.,Massachusetts General Hospital |
Qian J.,Harvard University |
Qian J.,University of Massachusetts Amherst |
Monsell S.E.,University of Washington |
And 4 more authors.
Journal of Neuropathology and Experimental Neurology | Year: 2013
To test the hypothesis that Alzheimer disease (AD) is a clinical and pathologic continuum between normal aging and end-stage dementia, we selected a convenience sample of subjects from the National Alzheimer Coordinating Center 2005 to 2012 autopsy cohort (n = 2,083) with the last clinical evaluation within 2 years before autopsy and no other primary neuropathologic diagnosis. Demographic and neuropathologic characteristics were correlated with the Clinical Dementia Rating-Sum of Boxes in the 835 subjects meeting these criteria. Both neuritic plaques and neurofibrillary tangles independently predicted Clinical Dementia Rating-Sum of Boxes. Severe small-vessel disease, severe amyloid angiopathy, and hippocampal sclerosis were also independently associated with the degree of cognitive impairment. By contrast, education was a strong independent protective factor against cognitive deficits. The cause of mild to moderate dementia remained uncertain in 14% of the patients. Inverse probability weighting suggests the generalizability of these results to nonautopsied cohorts. These data indicate that plaques and tangles independently contribute to cognitive impairment, that concurrent vascular disease strongly correlates with cognitive dysfunction even in a sample selected to represent the AD pathologic continuum, and that education further modifies clinical expression. Thus, multiple concomitant etiologies of brain damage and premorbid characteristics contribute to the uncertainty of AD clinicopathologic correlations based only on tangles and plaques. Copyright © 2013 by the American Association of Neuropathologists, Inc.