High Systolic Blood Pressure Induces Cerebral Microvascular Endothelial Dysfunction, Neurovascular Unit Damage, and Cognitive Decline in Mice

A chronic and gradual increase in pulse pressure (PP) is associated with cognitive decline and dementia in older individuals, but the mechanisms remain ill-defined. We hypothesized that a chronic elevation of PP would cause brain microvascular endothelial mechanical stress, damage the neurovascular unit, and ultimately induce cognitive impairment in mice, potentially contributing to the progression of vascular dementia and Alzheimer disease. To test our hypothesis, male control wild-type mice and Alzheimer disease model APP/PS1 (amyloid precursor protein/presenilin 1) mice were exposed to a transverse aortic constriction for 6 weeks, creating a PP overload in the right carotid (ipsilateral). We show that the transverse aortic constriction procedure associated with high PP induces a cascade of vascular damages in the ipsilateral parenchymal microcirculation: in wild-type mice, it impairs endothelial dilatory and blood brain barrier functions and causes microbleeds, a reduction in microvascular density, microvascular cell death by apoptosis, leading to severe hypoperfusion and parenchymal cell senescence. These damages were associated with brain inflammation and a significant reduction in learning and spatial memories. In APP/PS1 mice, that endogenously display severe cerebral vascular dysfunctions, microbleeds, parenchymal inflammation and cognitive dysfunction, transverse aortic constriction–induced high PP further aggravates cerebrovascular damage, Aβ (beta-amyloid) accumulation, and prevents learning. Our study, therefore, demonstrates that brain microvessels are vulnerable to a high PP and mechanical stress associated with transverse aortic constriction, promoting severe vascular dysfunction, disruption of the neurovascular unit, and cognitive decline. Hence, chronic elevated amplitude of the PP could contribute to the development and progression of vascular dementia including Alzheimer disease.

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Transcriptome Analysis of Hypertrophic Heart Tissues from Murine Transverse Aortic Constriction and Human Aortic Stenosis Reveals Key Genes and Transcription Factors Involved in Cardiac Remodeling Induced by Mechanical Stress

Disease Markers ◽

10.1155/2019/5058313 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10

Author(s):

Peng Yu ◽

Baoli Zhang ◽

Ming Liu ◽

Ying Yu ◽

Ji Zhao ◽

...

Keyword(s):

Gene Expression ◽

Transcription Factors ◽

Aortic Stenosis ◽

Mechanical Stress ◽

Cardiac Remodeling ◽

Interaction Network ◽

Cytokine Signaling ◽

Transverse Aortic Constriction ◽

Aortic Constriction ◽

Genomic Changes

Background. Mechanical stress-induced cardiac remodeling that results in heart failure is characterized by transcriptional reprogramming of gene expression. However, a systematic study of genomic changes involved in this process has not been performed to date. To investigate the genomic changes and underlying mechanism of cardiac remodeling, we collected and analyzed DNA microarray data for murine transverse aortic constriction (TAC) and human aortic stenosis (AS) from the Gene Expression Omnibus database and the European Bioinformatics Institute. Methods and Results. The differential expression genes (DEGs) across the datasets were merged. The Venn diagrams showed that the number of intersections for early and late cardiac remodeling was 74 and 16, respectively. Gene ontology and protein–protein interaction network analysis showed that metabolic changes, cell differentiation and growth, cell cycling, and collagen fibril organization accounted for a great portion of the DEGs in the TAC model, while in AS patients’ immune system signaling and cytokine signaling displayed the most significant changes. The intersections between the TAC model and AS patients were few. Nevertheless, the DEGs of the two species shared some common regulatory transcription factors (TFs), including SP1, CEBPB, PPARG, and NFKB1, when the heart was challenged by applied mechanical stress. Conclusions. This study unravels the complex transcriptome profiles of the heart tissues and highlighting the candidate genes involved in cardiac remodeling induced by mechanical stress may usher in a new era of precision diagnostics and treatment in patients with cardiac remodeling.

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Cardiac Microvascular Endothelial Cells in Pressure Overload–Induced Heart Disease

Circulation Heart Failure ◽

10.1161/circheartfailure.120.006979 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Sander Trenson ◽

Hadewich Hermans ◽

Sander Craps ◽

Peter Pokreisz ◽

Pauline de Zeeuw ◽

...

Keyword(s):

Endothelial Cells ◽

Left Ventricle ◽

Functional Status ◽

Right Atrium ◽

Pressure Overload ◽

Outflow Tract ◽

Microvascular Endothelial Cells ◽

Transverse Aortic Constriction ◽

Aortic Constriction ◽

Microvascular Endothelial

Background: Chronic pressure overload predisposes to heart failure, but the pathogenic role of microvascular endothelial cells (MiVEC) remains unknown. We characterized transcriptional, metabolic, and functional adaptation of cardiac MiVEC to pressure overload in mice and patients with aortic stenosis (AS). Methods: In Tie2-Gfp mice subjected to transverse aortic constriction or sham surgery, we performed RNA sequencing of isolated cardiac Gfp + -MiVEC and validated the signature in freshly isolated MiVEC from left ventricle outflow tract and right atrium of patients with AS. We next compared their angiogenic and metabolic profiles and finally correlated molecular and pathological signatures with clinical phenotypes of 42 patients with AS (50% women). Results: In mice, transverse aortic constriction induced progressive systolic dysfunction, fibrosis, and reduced microvascular density. After 10 weeks, 25 genes predominantly involved in matrix-regulation were >2-fold upregulated in isolated MiVEC. Increased transcript levels of Cartilage Intermediate Layer Protein ( Cilp ), Thrombospondin-4 , Adamtsl-2 , and Collagen1a1 were confirmed by quantitative reverse transcription polymerase chain reaction and recapitulated in left ventricle outflow tract-derived MiVEC of AS ( P <0.05 versus right atrium-MiVEC). Fatty acid oxidation increased >2-fold in left ventricle outflow tract-MiVEC, proline content by 130% (median, IQR, 58%–474%; P =0.008) and procollagen secretion by 85% (mean [95% CI, 16%–154%]; P <0.05 versus right atrium-MiVEC for all). The altered transcriptome in left ventricle outflow tract-MiVEC was associated with impaired 2-dimensional-vascular network formation and 3-dimensional-spheroid sprouting ( P <0.05 versus right atrium-MiVEC), profibrotic ultrastructural changes, and impaired diastolic left ventricle function, capillary density and functional status, especially in female AS. Conclusions: Pressure overload induces major transcriptional and metabolic adaptations in cardiac MiVEC resulting in excess interstitial fibrosis and impaired angiogenesis. Molecular rewiring of MiVEC is worse in women, compromises functional status, and identifies novel targets for intervention.

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Pre-symptomatic Caspase-1 inhibitor delays cognitive decline in a mouse model of Alzheimer disease and aging

Nature Communications ◽

10.1038/s41467-020-18405-9 ◽

2020 ◽

Vol 11 (1) ◽

Author(s):

Joseph Flores ◽

Anastasia Noël ◽

Bénédicte Foveau ◽

Olivier Beauchet ◽

Andréa C. LeBlanc

Keyword(s):

Alzheimer Disease ◽

Cognitive Deficits ◽

Microglial Activation ◽

Symptomatic Treatment ◽

Memory Deficits ◽

Brain Inflammation ◽

Therapeutic Interventions ◽

Wild Type ◽

Caspase 1 ◽

Beta Peptide

Abstract Early therapeutic interventions are essential to prevent Alzheimer Disease (AD). The association of several inflammation-related genetic markers with AD and the early activation of pro-inflammatory pathways in AD suggest inflammation as a plausible therapeutic target. Inflammatory Caspase-1 has a significant impact on AD-like pathophysiology and Caspase-1 inhibitor, VX-765, reverses cognitive deficits in AD mouse models. Here, a one-month pre-symptomatic treatment of Swedish/Indiana mutant amyloid precursor protein (APPSw/Ind) J20 and wild-type mice with VX-765 delays both APPSw/Ind- and age-induced episodic and spatial memory deficits. VX-765 delays inflammation without considerably affecting soluble and aggregated amyloid beta peptide (Aβ) levels. Episodic memory scores correlate negatively with microglial activation. These results suggest that Caspase-1-mediated inflammation occurs early in the disease and raise hope that VX-765, a previously Food and Drug Administration-approved drug for human CNS clinical trials, may be a useful drug to prevent the onset of cognitive deficits and brain inflammation in AD.

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Abstract 200: Beta-Myosin Heavy Chain Induction after Pressure Overload Is in a Minor Sub-population of Myocytes and Requires the Alpha-1A-Adrenergic Receptor

Circulation ◽

10.1161/circ.116.suppl_16.ii_19 ◽

2007 ◽

Vol 116 (suppl_16) ◽

Author(s):

Javier E Lopez ◽

Bat-Erdene Myagmar ◽

Philip Swigart ◽

Marty Bigos ◽

Manoj Rodrigo ◽

...

Keyword(s):

Myosin Heavy Chain ◽

Heavy Chain ◽

Adrenergic Receptor ◽

Pressure Overload ◽

Transverse Aortic Constriction ◽

Wild Type ◽

Rt Pcr ◽

Aortic Constriction ◽

Double Knockout ◽

A Minor

Background: Induction of the fetal hypertrophic gene beta-myosin heavy chain (MHC) is a signature feature of pressure overload, and is thought to occur in most hypertrophied myocytes. Beta-MHC mRNA is not induced after transverse aortic constriction (TAC) in a double knockout (KO) model of the alpha-1A and alpha-1B-adrenergic receptor (AR) subtypes, but it is unknown whether the A or B or both are required. Hypothesis: We tested the hypothesis that native beta-MHC protein induction is in a sub-population of myocytes and requires only a single alpha-1 subtype. Methods: TAC was done in wild type (WT) and alpha-1 KO male mice ages 12–14 weeks. Beta-MHC protein was measured in isolated adult myocytes by a novel flow cytometry approach, with antibodies validated for beta-MHC and total sarcomeric MHC. Results: In WT mice, the fraction of myocytes expressing beta-MHC was 3% in shams (SE =1, n =4 hearts), and increased to 26% of myocytes at 1–3 weeks after TAC (SE =4, n =8, p< 0.01 vs. sham). Myocytes expressing beta-MHC were predominantly large cells (see Figure ). In alpha-1A KO mice (AKO), beta-MHC was induced in only 6% of myocytes (SE =2, n =3, p<0.05 vs. WT TAC, p =NS vs. sham), or in only 15% as many myocytes as in WT hearts. Western blotting and quantitative RT-PCR confirmed reduced beta-MHC induction in alpha-1A KO myocytes. Conclusion: Beta-MHC induction after pressure overload is in only a minor sub-population of cardiac myocytes, contrary to common models of fetal hypertrophic gene induction. Furthermore, beta-MHC induction requires a single alpha-1-AR subtype, the alpha-1A, which cannot be compensated by other hypertrophic receptors.

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A disintegrin and metalloproteinase 12 prevents heart failure by regulating cardiac hypertrophy and fibrosis

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00496.2019 ◽

2020 ◽

Vol 318 (2) ◽

pp. H238-H251 ◽

Cited By ~ 2

Author(s):

Yuto Nakamura ◽

Shunbun Kita ◽

Yoshimitsu Tanaka ◽

Shiro Fukuda ◽

Yoshinari Obata ◽

...

Keyword(s):

Cardiac Hypertrophy ◽

Cardiac Function ◽

Focal Adhesion ◽

Cardiac Dysfunction ◽

Transverse Aortic Constriction ◽

Wild Type ◽

Aortic Constriction ◽

A Disintegrin And Metalloproteinase ◽

Adam 12

A disintegrin and metalloproteinase (ADAM)12 is considered to promote cardiac dysfunction based on the finding that a small-molecule ADAM12 inhibitor, KB-R7785, ameliorated cardiac function in a transverse aortic constriction (TAC) model by inhibiting the proteolytic activation of heparin-binding-EGF signaling. However, this compound has poor selectivity for ADAM12, and the role of ADAM12 in cardiac dysfunction has not yet been investigated using genetic loss-of-function mice. We revealed that ADAM12 knockout mice showed significantly more advanced cardiac hypertrophy and higher mortality rates than wild-type mice 4 wk after TAC surgery. An ADAM12 deficiency resulted in significantly more expanded cardiac fibrosis accompanied by increased collagen-related gene expression in failing hearts. The results of a genome-wide transcriptional analysis suggested a strongly enhanced focal adhesion- and fibrosis-related signaling pathway in ADAM12 knockout hearts. The loss of ADAM12 increased the abundance of the integrinβ1 subunit and transforming growth factor (TGF)-β receptor types I and III, and this was followed by the phosphorylation of focal adhesion kinase, Akt, mammalian target of rapamycin, ERK, and Smad2/3 in the heart, which resulted in cardiac dysfunction. The present results revealed that the loss of ADAM12 enhanced focal adhesion and canonical TGF-β signaling by regulating the abundance of the integrinβ1 and TGF-β receptors. NEW & NOTEWORTHY In contrast to a long-believed cardio-damaging role of a disintegrin and metalloproteinase (ADAM)12, cardiac hypertrophy was more severe, cardiac function was lower, and mortality was higher in ADAM12 knockout mice than in wild-type mice after transverse aortic constriction surgery. The loss of ADAM12 enhanced focal adhesion- and fibrosis-related signaling pathways in the heart, which may compromise cardiac function. These results provide insights for the development of novel therapeutics that target ADAM12 to treat heart failure.

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Innate Immune Nod1/RIP2 Signaling Is Essential for Cardiac Hypertrophy but Requires Mitochondrial Antiviral Signaling Protein for Signal Transductions and Energy Balance

Circulation ◽

10.1161/circulationaha.119.041213 ◽

2020 ◽

Vol 142 (23) ◽

pp. 2240-2258 ◽

Cited By ~ 1

Author(s):

Han-Bin Lin ◽

Kotaro Naito ◽

Yena Oh ◽

Gedaliah Farber ◽

Georges Kanaan ◽

...

Keyword(s):

Heart Failure ◽

Cardiac Hypertrophy ◽

Cardiac Remodeling ◽

Innate Immune ◽

Transverse Aortic Constriction ◽

Wild Type ◽

Aortic Constriction ◽

Antiviral Signaling ◽

Mitochondrial Antiviral Signaling ◽

Mitochondrial Antiviral Signaling Protein

Background: Cardiac hypertrophy is a key biological response to injurious stresses such as pressure overload and, when excessive, can lead to heart failure. Innate immune activation by danger signals, through intracellular pattern recognition receptors such as nucleotide-binding oligomerization domain 1 (Nod1) and its adaptor receptor-interacting protein 2 (RIP2), might play a major role in cardiac remodeling and progression to heart failure. We hypothesize that Nod1/RIP2 are major contributors to cardiac hypertrophy, but may not be sufficient to fully express the phenotype alone. Methods: To elucidate the contribution of Nod1/RIP2 signaling to cardiac hypertrophy, we randomized Nod1 –/– , RIP2 –/– , or wild-type mice to transverse aortic constriction or sham operations. Cardiac hypertrophy, fibrosis, and cardiac function were examined in these mice. Results: Nod1 and RIP2 proteins were upregulated in the heart after transverse aortic constriction, and this was paralleled by increased expression of mitochondrial proteins, including mitochondrial antiviral signaling protein (MAVS). Nod1 –/– and RIP2 –/– mice subjected to transverse aortic constriction exhibited better survival, improved cardiac function, and decreased cardiac hypertrophy. Downstream signal transduction pathways that regulate inflammation and fibrosis, including NF (nuclear factor) κB and MAPK (mitogen-activated protein kinase)-GATA4/p300, were reduced in both Nod1 –/– and RIP2 –/– mice after transverse aortic constriction compared with wild-type mice. Coimmunoprecipitation of extracted cardiac proteins and confocal immunofluorescence microscopy showed that Nod1/RIP2 interaction was robust and that this complex also included MAVS as an essential component. Suppression of MAVS expression attenuated the complex formation, NF κB signaling, and myocyte hypertrophy. Interrogation of mitochondrial function compared in the presence or ablation of MAVS revealed that MAVS serves to suppress mitochondrial energy output and mediate fission/fusion related dynamic changes. The latter is possibly linked to mitophagy during cardiomyocytes stress, which may provide an intriguing link between innate immune activation and mitochondrial energy balance under stress or injury conditions. Conclusions: We have identified that innate immune Nod1/RIP2 signaling is a major contributor to cardiac remodeling after stress. This process is critically joined by and regulated through the mitochondrial danger signal adapter MAVS. This novel complex coordinates remodeling, inflammatory response, and mitochondrial energy metabolism in stressed cardiomyocytes. Thus, Nod1/RIP2/MAVS signaling complex may represent an attractive new therapeutic approach toward heart failure.

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Resveratrol Reduces Matrix Metalloproteinase-2 Activity Induced by Oxygen-Glucose Deprivation and Reoxygenation in Human Cerebral Microvascular Endothelial Cells

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000119 ◽

2012 ◽

Vol 82 (4) ◽

pp. 267-274 ◽

Cited By ~ 5

Author(s):

Zahide Cavdar ◽

Mehtap Y. Egrilmez ◽

Zekiye S. Altun ◽

Nur Arslan ◽

Nilgun Yener ◽

...

Keyword(s):

Endothelial Cells ◽

Neuroprotective Effect ◽

Ischemia Reperfusion ◽

Neurovascular Unit ◽

Glucose Deprivation ◽

Matrix Metalloproteinase 2 ◽

Microvascular Endothelial Cells ◽

Oxygen Glucose Deprivation ◽

Microvascular Endothelial

The main pathophysiology in cerebral ischemia is the structural alteration in the neurovascular unit, coinciding with neurovascular matrix degradation. Among the human matrix metalloproteinases (MMPs), MMP-2 and -9, known as gelatinases, are the key enzymes for degrading type IV collagen, which is the major component of the basal membrane that surrounds the cerebral blood vessel. In the present study, we investigated the effects of resveratrol on cytotoxicity, reactive oxygen species (ROS), and gelatinases (MMP-2 and -9) in human cerebral microvascular endothelial cells exposed to 6 hours of oxygen-glucose deprivation and a subsequent 24 hours of reoxygenation with glucose (OGD/R), to mimic ischemia/reperfusion in vivo. Lactate dehydrogenase increased significantly, in comparison to that in the normoxia group. ROS was markedly increased in the OGD/R group, compared to normoxia. Correspondingly, ROS was significantly reduced with 50 μM of resveratrol. The proMMP-2 activity in the OGD/R group showed a statistically significant increase from the control cells. Resveratrol preconditioning decreased significantly the proMMP-2 in the cells exposed to OGD/R in comparison to that in the OGD/R group. Our results indicate that resveratrol regulates MMP-2 activity induced by OGD/R via its antioxidant effect, implying a possible mechanism related to the neuroprotective effect of resveratrol.

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The Spectrum of Cerebrovascular Disease and Associated Cognitive Decline

The Oxford Handbook of Adult Cognitive Disorders ◽

10.1093/oxfordhb/9780190664121.013.27 ◽

2019 ◽

pp. 574-599

Author(s):

Victoria J. Williams ◽

Steven E. Arnold ◽

David H. Salat

Keyword(s):

Risk Factors ◽

Cognitive Impairment ◽

Cerebrovascular Disease ◽

Cognitive Decline ◽

Vascular Dementia ◽

Structure And Function ◽

Vascular Risk Factors ◽

Vascular Health ◽

Vascular Risk ◽

And Function

Throughout the lifespan, common variations in systemic health and illness contribute to alterations in vasculature structure and function throughout the body, significantly increasing risk for cardiovascular and cerebrovascular disease (CVD). CVD is a prevalent cause of mortality in late life; it also promotes brain alterations, contributing to cognitive decline and, when severe, vascular dementia. Even prior to diseased states, individual variation in CVD risk is associated with structural and functional brain alterations. Yet, how cumulative asymptomatic alterations in vessel structure and function contribute to more subtle changes in brain tissue integrity and function that emerge in late life is unclear. Finally, vascular risk factors are associated with the clinical progression of neurodegenerative diseases such as Alzheimer’s disease (AD); however, recent theory posits that vascular degeneration may serve a contributory role in these conditions. This chapter reviews how lifespan changes in vascular health contribute to degenerative changes in neural tissue and the subsequent development of cognitive impairment and/or vascular dementia. It first discusses associations between vascular risk factors and cognition and also how declining vascular health may lead to cognitive impairment and dementia. Next, it identifies basic aspects of cerebrovascular anatomy and physiology sustaining tissue health and discusses how vulnerabilities of this system contribute to neurodegenerative changes. Finally, it reviews evidence of vascular contributions to AD and presents ideas for future research to better understand the full spectrum of cerebrovascular contributions to brain aging, cognitive decline, and dementia.

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