Author
Jacob Raber
Other affiliations: Scripps Health, University of California, San Francisco, Oregon National Primate Research Center
Bio: Jacob Raber is an academic researcher from Oregon Health & Science University. The author has contributed to research in topics: Apolipoprotein E & Water maze. The author has an hindex of 53, co-authored 230 publications receiving 11862 citations. Previous affiliations of Jacob Raber include Scripps Health & University of California, San Francisco.
Papers published on a yearly basis
Papers
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TL;DR: It is shown that Dgat-deficient (Dgat−/−) mice are viable and can still synthesize triglycerides, and these mice are lean and resistant to diet-induced obesity.
Abstract: Triglycerides (or triacylglycerols) represent the major form of stored energy in eukaryotes Triglyceride synthesis has been assumed to occur primarily through acyl CoA:diacylglycerol transferase (Dgat), a microsomal enzyme that catalyses the final and only committed step in the glycerol phosphate pathway Therefore, Dgat has been considered necessary for adipose tissue formation and essential for survival Here we show that Dgat-deficient (Dgat-/-) mice are viable and can still synthesize triglycerides Moreover, these mice are lean and resistant to diet-induced obesity The obesity resistance involves increased energy expenditure and increased activity Dgat deficiency also alters triglyceride metabolism in other tissues, including the mammary gland, where lactation is defective in Dgat-/- females Our findings indicate that multiple mechanisms exist for triglyceride synthesis and suggest that the selective inhibition of Dgat-mediated triglyceride synthesis may be useful for treating obesity
918 citations
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TL;DR: Evidence is provided that irradiation of young animals induces a long-term impairment of dentate subgranular zone neurogenesis that is associated with hippocampal-dependent memory deficits.
668 citations
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TL;DR: It is shown that the Barnes maze is particularly sensitive for the detection of radiation-induced cognitive deficits in young adult mice and the significant loss of proliferating SGZ cells and their progeny suggests a contributory role of reduced neurogenesis in the pathogenesis of radiation -induced cognitive impairments.
Abstract: During treatment of brain tumors, some head and neck tumors, and other diseases, like arteriovenous malformations, the normal brain is exposed to ionizing radiation. While high radiation doses can cause severe tissue destruction, lower doses can induce cognitive impairments without signs of overt tissue damage. The underlying pathogenesis of these impairments is not well understood but may involve the neural precursor cells in the dentate gyrus of the hippocampus. To assess the effects of radiation on cognitive function, 2-month-old mice received either sham treatment (controls) or localized X irradiation (10 Gy) to the hippocampus/cortex and were tested behaviorally 3 months later. Compared to controls, X-irradiated mice showed hippocampal-dependent spatial learning and memory impairments in the Barnes maze but not the Morris water maze. No nonspatial learning and memory impairments were detected. The cognitive impairments were associated with reductions in proliferating Ki-67-positive cells and Doublecortin-positive immature neurons in the subgranular zone (SGZ) of the dentate gyrus. This study shows significant cognitive impairments after a modest dose of radiation and demonstrates that the Barnes maze is particularly sensitive for the detection of radiation-induced cognitive deficits in young adult mice. The significant loss of proliferating SGZ cells and their progeny suggests a contributory role of reduced neurogenesis in the pathogenesis of radiation-induced cognitive impairments.
642 citations
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TL;DR: Evidence is provided that apolipoprotein E (apoE) genotype accounts for the majority of Alzheimer's disease (AD) risk and pathology.
555 citations
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TL;DR: It is shown that glia, like neurons, are integral components of the neuropathology of RTT, and supports the targeting of glia as a strategy for improving the associated symptoms.
Abstract: Rett's syndrome (RTT) is an X-chromosome-linked autism spectrum disorder caused by loss of function of the transcription factor methyl-CpG-binding protein 2 (MeCP2). Although MeCP2 is expressed in most tissues, loss of MeCP2 expression results primarily in neurological symptoms. Earlier studies suggested the idea that RTT is due exclusively to loss of MeCP2 function in neurons. Although defective neurons clearly underlie the aberrant behaviours, we and others showed recently that the loss of MECP2 from glia negatively influences neurons in a non-cell-autonomous fashion. Here we show that in globally MeCP2-deficient mice, re-expression of Mecp2 preferentially in astrocytes significantly improved locomotion and anxiety levels, restored respiratory abnormalities to a normal pattern, and greatly prolonged lifespan compared to globally null mice. Furthermore, restoration of MeCP2 in the mutant astrocytes exerted a non-cell-autonomous positive effect on mutant neurons in vivo, restoring normal dendritic morphology and increasing levels of the excitatory glutamate transporter VGLUT1. Our study shows that glia, like neurons, are integral components of the neuropathology of RTT, and supports the targeting of glia as a strategy for improving the associated symptoms.
455 citations
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TL;DR: Recent studies have begun to shed light on the physiological functions of MAPK cascades in the control of gene expression, cell proliferation and programmed cell death.
Abstract: Mitogen-activated protein kinases (MAPKs) are important signal transducing enzymes, unique to eukaryotes, that are involved in many facets of cellular regulation. Initial research concentrated on defining the components and organization of MAPK signalling cascades, but recent studies have begun to shed light on the physiological functions of these cascades in the control of gene expression, cell proliferation and programmed cell death.
4,973 citations
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TL;DR: The authors' data provide clues as to how neurons and astrocytes differ in their ability to dynamically regulate glycolytic flux and lactate generation attributable to unique splicing of PKM2, the gene encoding the glycoleytic enzyme pyruvate kinase.
Abstract: The major cell classes of the brain differ in their developmental processes, metabolism, signaling, and function To better understand the functions and interactions of the cell types that comprise these classes, we acutely purified representative populations of neurons, astrocytes, oligodendrocyte precursor cells, newly formed oligodendrocytes, myelinating oligodendrocytes, microglia, endothelial cells, and pericytes from mouse cerebral cortex We generated a transcriptome database for these eight cell types by RNA sequencing and used a sensitive algorithm to detect alternative splicing events in each cell type Bioinformatic analyses identified thousands of new cell type-enriched genes and splicing isoforms that will provide novel markers for cell identification, tools for genetic manipulation, and insights into the biology of the brain For example, our data provide clues as to how neurons and astrocytes differ in their ability to dynamically regulate glycolytic flux and lactate generation attributable to unique splicing of PKM2, the gene encoding the glycolytic enzyme pyruvate kinase This dataset will provide a powerful new resource for understanding the development and function of the brain To ensure the widespread distribution of these datasets, we have created a user-friendly website (http://webstanfordedu/group/barres_lab/brain_rnaseqhtml) that provides a platform for analyzing and comparing transciption and alternative splicing profiles for various cell classes in the brain
3,891 citations
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TL;DR: This report provides information to increase understanding of the public health impact of Alzheimer's disease (AD), including incidence and prevalence, mortality rates, health expenditures and costs of care, and effect on caregivers and society in general.
Abstract: This report provides information to increase understanding of the public health impact of Alzheimer's disease (AD), including incidence and prevalence, mortality rates, health expenditures and costs of care, and effect on caregivers and society in general. It also explores the roles and unique challenges of long‐distance caregivers, as well as interventions that target those challenges. An estimated 5.2 million Americans have AD. Approximately 200,000 people younger than 65 years with AD comprise the younger onset AD population; 5 million comprise the older onset AD population. Throughout the coming decades, the baby boom generation is projected to add about 10 million to the total number of people in the United States with AD. Today, someone in America develops AD every 68 seconds. By 2050, one new case of AD is expected to develop every 33 seconds, or nearly a million new cases per year, and the total estimated prevalence is expected to be 13.8 million. AD is the sixth leading cause of death in the United States and the fifth leading cause of death in Americans age 65 years or older. Between 2000 and 2010, the proportion of deaths resulting from heart disease, stroke, and prostate cancer decreased 16%, 23%, and 8%, respectively, whereas the proportion resulting from AD increased 68%. The number of deaths from AD as determined by official death certificates (83,494 in 2010) likely underrepresents the number of AD‐related deaths in the United States. A projected 450,000 older Americans with AD will die in 2013, and a large proportion will die as a result of complications of AD. In 2012, more than 15 million family members and other unpaid caregivers provided an estimated 17.5 billion hours of care to people with AD and other dementias, a contribution valued at more than $216 billion. Medicare payments for services to beneficiaries age 65 years and older with AD and other dementias are three times as great as payments for beneficiaries without these conditions, and Medicaid payments are 19 times as great. Total payments in 2013 for health care, long‐term care, and hospice services for people age 65 years and older with dementia are expected to be $203 billion (not including the contributions of unpaid caregivers). An estimated 2.3 million caregivers of people with AD and other dementias live at least 1 hour away from the care recipient. These “long‐distance caregivers” face unique challenges, including difficulty in assessing the care recipient's true health condition and needs, high rates of family disagreement regarding caregiving decisions, and high out‐of‐pocket expenses for costs related to caregiving. Out‐of‐pocket costs for long‐distance caregivers are almost twice as high as for local caregivers.
2,988 citations
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TL;DR: The factors that regulate proliferation and fate determination of adult neural stem cells are discussed and the potential significance of adult neurogenesis in memory, depression, and neurodegenerative disorders such as Alzheimer's and Parkinson's disease is addressed.
2,911 citations