For the competing renewal of our R01NS34467-19 project, we propose to continue collaborative studies between the Zlokovic and the Holtzman labs aimed at understanding at the cellular, molecular and systems level, and in allele-specific and gender-specific manner apolipoprotein E (apoE) effects on the cerebrovascular system, specifically, 1) how they contribute to Alzheimer?s disease (AD) neurovascular dysfunction, neurodegenerative, amyloid-? (A?) and tau disorders; and 2) how targeting apoE-low density lipoprotein receptor-related protein 1 (LRP1) interactions on different cerebrovascular cell types can mitigate and/or block cerebrovascular and brain damage causing dementia in AD. We will focus on APOE4, the strongest genetic risk factor for AD, and APOE3 that carries a significantly lower risk for AD. Neurovascular apoE is produced by astrocytes, pericytes, and vascular smooth muscle cells (VSMCs). Based on published and our pilot data, we hypothesize that apoE isoform-specific interactions with LRP1 on brain vascular cells provide a pathogenic link to apoE-related cerebrovascular disorder by controlling in an apoE-isoform-specific manner: 1) cyclophilin A (CypA)-matrix- metalloproteinase 9 (MMP9) pathway which disrupts blood-brain barrier (BBB) and arterial blood vessels; and 2) Ab and tau clearance on capillary and arterial vessels. Specifically, the apoE4 pathophysiological cerebrovascular effects accelerate cerebrovascular, neurodegenerative, Ab and tau disorders, whereas apoE3 has less disruptive effects. ApoE allele-specific effects on BBB integrity, vascular and neuronal function and structure will be studied in new APOE knockinflox/flox E3F and E4F mice with apoE cell-specific deletion from astrocytes, pericytes, or VSMCs (AIM 1); and, in the context of Ab and tau pathology, in APP/PS1-21 mice (AIM 2) and P301S tau mice (AIM 3), respectively, crossed with our new E3F and E4F mice with apoE cell-specific deletion from astrocytes, pericytes, or VSMCs. We will therapeutically target LRP1 and CypA-MMP9 pathway with intravenous cell-specific adeno-associated virus (AAV)-mediated delivery of LRP1 minigene to endothelium and pericytes, and CypA inhibition with Debio 025. Understanding the effects of astrocyte-derived, pericyte- derived and/or VSMC-derived apoE on cerebrovascular and neuronal functions, Ab and tau clearance and pathology, in an allele-specific and gender-specific manner, will advance our understanding of the pathogenesis and treatment of AD neurovascular dysfunction, neurodegeneration, Ab and tau disorders. If successful, this could lead to new therapeutic approaches targeting LRP1 and/or CypA-MMP9 pathway in different brain vascular cells to mitigate and/or block apoE?s cerebrovascular and brain damage causing dementia in AD.

Public Health Relevance

The annual health care costs for neurodegenerative disorders range in excess of a hundred billion dollars. Sadly, we do not have cure yet for any of these diseases. Understanding cellular and molecular mechanisms underlying effects of apolipoprotein E (apoE) on the cerebrovascular system and how these effects may contribute to development of neuronal dysfunction and neurodegeneration, amyloid-beta and tau disorders will have profound implications for our understanding of Alzheimer?s disease pathogenesis and may ultimately guide the development of new therapeutic approaches for this devastating brain disorder.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
5R01NS034467-22
Application #
10092227
Study Section
Brain Injury and Neurovascular Pathologies Study Section (BINP)
Program Officer
Corriveau, Roderick A
Project Start
1995-09-01
Project End
2025-02-28
Budget Start
2021-03-01
Budget End
2022-02-28
Support Year
22
Fiscal Year
2021
Total Cost
Indirect Cost
Name
University of Southern California
Department
Physiology
Type
Schools of Medicine
DUNS #
072933393
City
Los Angeles
State
CA
Country
United States
Zip Code
90089
Shi, Yingxiao; Lin, Shaoyu; Staats, Kim A et al. (2018) Haploinsufficiency leads to neurodegeneration in C9ORF72 ALS/FTD human induced motor neurons. Nat Med 24:313-325
Sweeney, Melanie D; Kisler, Kassandra; Montagne, Axel et al. (2018) The role of brain vasculature in neurodegenerative disorders. Nat Neurosci 21:1318-1331
Montagne, Axel; Nikolakopoulou, Angeliki M; Zhao, Zhen et al. (2018) Pericyte degeneration causes white matter dysfunction in the mouse central nervous system. Nat Med 24:326-337
Sweeney, Melanie D; Zlokovic, Berislav V (2018) A lymphatic waste-disposal system implicated in Alzheimer's disease. Nature 560:172-174
Sweeney, Melanie D; Sagare, Abhay P; Zlokovic, Berislav V (2018) Blood-brain barrier breakdown in Alzheimer disease and other neurodegenerative disorders. Nat Rev Neurol 14:133-150
Kisler, Kassandra; Nelson, Amy R; Montagne, Axel et al. (2017) Cerebral blood flow regulation and neurovascular dysfunction in Alzheimer disease. Nat Rev Neurosci 18:419-434
Huynh, Tien-Phat V; Liao, Fan; Francis, Caroline M et al. (2017) Age-Dependent Effects of apoE Reduction Using Antisense Oligonucleotides in a Model of ?-amyloidosis. Neuron 96:1013-1023.e4
Nelson, Amy R; Sagare, Abhay P; Zlokovic, Berislav V (2017) Role of clusterin in the brain vascular clearance of amyloid-?. Proc Natl Acad Sci U S A 114:8681-8682
Kisler, Kassandra; Nelson, Amy R; Rege, Sanket V et al. (2017) Pericyte degeneration leads to neurovascular uncoupling and limits oxygen supply to brain. Nat Neurosci 20:406-416
Nikolakopoulou, Angeliki Maria; Zhao, Zhen; Montagne, Axel et al. (2017) Regional early and progressive loss of brain pericytes but not vascular smooth muscle cells in adult mice with disrupted platelet-derived growth factor receptor-? signaling. PLoS One 12:e0176225

Showing the most recent 10 out of 76 publications