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Waigi EW, Pernomian L, Crockett AM, Costa TJ, Townsend P, Webb RC, McQuail JA, McCarthy CG, Hollis F, Wenceslau CF. Vascular dysfunction occurs prior to the onset of amyloid pathology and Aβ plaque deposits colocalize with endothelial cells in the hippocampus of female APPswe/PSEN1dE9 mice. GeroScience 2024:10.1007/s11357-024-01213-0. [PMID: 38862757 DOI: 10.1007/s11357-024-01213-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Accepted: 05/18/2024] [Indexed: 06/13/2024] Open
Abstract
Increasing evidence shows that cardiovascular diseases (CVDs) are associated with an increased risk of cognitive impairment and Alzheimer's diseases (AD). It is unknown whether systemic vascular dysfunction occurs prior to the development of AD, if this occurs in a sex-dependent manner, and whether endothelial cells play a role in the deposition of amyloid beta (Aβ) peptides. We hypothesized that vascular dysfunction occurs prior to the onset of amyloid pathology, thus escalating its progression. Furthermore, endothelial cells from female mice will present with an exacerbated formation of Aβ peptides due to an exacerbated pressure pulsatility. To test this hypothesis, we used a double transgenic mouse model of early-onset AD (APPswe/PSEN1dE9). We evaluated hippocampus-dependent recognition memory and the cardiovascular function by echocardiography and direct measurements of blood pressure through carotid artery catheterization. Vascular function was evaluated in resistance arteries, morphometric parameters in the aortas, and immunofluorescence in the hippocampus and aortas. We observed that endothelial dysfunction occurred prior to the onset of amyloid pathology irrespective of sex. However, during the onset of amyloid pathology, only female APP/PS1 mice had vascular stiffness in the aorta. There was elevated Aβ deposition which colocalized with endothelial cells in the hippocampus from female APP/PS1 mice. Overall, these data showed that vascular abnormalities may be an early marker, and potential mediator of AD, but exacerbated aortic stiffness and pressure pulsatility after the onset of amyloid pathology may be associated with a greater burden of Aβ formation in hippocampal endothelial cells from female but not male APP/PS1 mice.
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Affiliation(s)
- Emily W Waigi
- Cardiovascular Translational Research Center, Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC, USA
| | - Laena Pernomian
- Cardiovascular Translational Research Center, Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC, USA
| | - Alexia M Crockett
- Cardiovascular Translational Research Center, Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC, USA
- Department of Pharmacology, Physiology and Neuroscience, University of South Carolina School of Medicine, Columbia, SC, USA
| | - Tiago J Costa
- Cardiovascular Translational Research Center, Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC, USA
| | - Paul Townsend
- Cardiovascular Translational Research Center, Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC, USA
| | - R Clinton Webb
- Cardiovascular Translational Research Center, Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC, USA
- Department of Biomedical Engineering, College of Engineering and Computing, University of South Carolina, Columbia, SC, USA
| | - Joseph A McQuail
- Department of Pharmacology, Physiology and Neuroscience, University of South Carolina School of Medicine, Columbia, SC, USA
| | - Cameron G McCarthy
- Cardiovascular Translational Research Center, Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC, USA
- Department of Biomedical Engineering, College of Engineering and Computing, University of South Carolina, Columbia, SC, USA
| | - Fiona Hollis
- Department of Pharmacology, Physiology and Neuroscience, University of South Carolina School of Medicine, Columbia, SC, USA
| | - Camilla F Wenceslau
- Cardiovascular Translational Research Center, Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC, USA.
- Department of Biomedical Engineering, College of Engineering and Computing, University of South Carolina, Columbia, SC, USA.
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Maleki B, Modarres P, Salehi P, Vallian S. Identification of ITPR1 gene as a novel target for hsa-miR-34b-5p in non-obstructive azoospermia: a Ca 2+/apoptosis pathway cross-talk. Sci Rep 2023; 13:21873. [PMID: 38072953 PMCID: PMC10710998 DOI: 10.1038/s41598-023-49155-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 12/05/2023] [Indexed: 12/18/2023] Open
Abstract
MiR-34b-5p has been reported as a non-invasive diagnostic biomarker for infertility. However, no gene targets regulating the mechanism of cation of this miRNA are known. In this study, using gene set enrichment analysis the Inositol 1,4,5-Trisphosphate Receptor Type 1 (ITPR1) gene was identified as the sole target for hsa-miR-34b-5p, and found significantly overexpressed in non-obstructive azoospermia (NOA) patients. This finding was confirmed by qRT-PCR on fresh testicular tissues from NOA patients. Then, pathway enrichment analysis as well as the diagnostic value analysis of hsa-miR-34b-5p/ITPR1 indicated ITPR1 as a hub gene in the calcium (Ca2+)-apoptosis pathway, and a valuable predictive biomarker for NOA. Moreover, gene expression and histological assays showed the association of the effects of ITPR1's increased expression on spermatogenesis failure through induction of apoptosis in NOA patients. These data suggested that the hsa-miR-34b-5p/ITPR1 axis could serve as a potential regulatory predictive biomarker for human spermatogenesis through the Ca2+-apoptosis pathway cross-talk.
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Affiliation(s)
- Bahareh Maleki
- Department of Cell and Molecular Biology and Microbiology, Faculty of Biological Science and Technology, University of Isfahan, Isfahan, Islamic Republic of Iran
| | - Parastoo Modarres
- Department of Cell and Molecular Biology and Microbiology, Faculty of Biological Science and Technology, University of Isfahan, Isfahan, Islamic Republic of Iran
| | - Peyman Salehi
- Department of Infertility, Milad Hospital, Isfahan University of Medical Sciences, Isfahan, Islamic Republic of Iran
| | - Sadeq Vallian
- Department of Cell and Molecular Biology and Microbiology, Faculty of Biological Science and Technology, University of Isfahan, Isfahan, Islamic Republic of Iran.
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3
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Waigi EW, Webb RC, Moss MA, Uline MJ, McCarthy CG, Wenceslau CF. Soluble and insoluble protein aggregates, endoplasmic reticulum stress, and vascular dysfunction in Alzheimer's disease and cardiovascular diseases. GeroScience 2023; 45:1411-1438. [PMID: 36823398 PMCID: PMC10400528 DOI: 10.1007/s11357-023-00748-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 01/28/2023] [Indexed: 02/25/2023] Open
Abstract
Dementia refers to a particular group of symptoms characterized by difficulties with memory, language, problem-solving, and other thinking skills that affect a person's ability to perform everyday activities. Alzheimer's disease (AD) is the most common form of dementia, affecting about 6.2 million Americans aged 65 years and older. Likewise, cardiovascular diseases (CVDs) are a major cause of disability and premature death, impacting 126.9 million adults in the USA, a number that increases with age. Consequently, CVDs and cardiovascular risk factors are associated with an increased risk of AD and cognitive impairment. They share important age-related cardiometabolic and lifestyle risk factors, that make them among the leading causes of death. Additionally, there are several premises and hypotheses about the mechanisms underlying the association between AD and CVD. Although AD and CVD may be considered deleterious to health, the study of their combination constitutes a clinical challenge, and investigations to understand the mechanistic pathways for the cause-effect and/or shared pathology between these two disease constellations remains an active area of research. AD pathology is propagated by the amyloid β (Aβ) peptides. These peptides give rise to small, toxic, and soluble Aβ oligomers (SPOs) that are nonfibrillar, and it is their levels that show a robust correlation with the extent of cognitive impairment. This review will elucidate the interplay between the effects of accumulating SPOs in AD and CVDs, the resulting ER stress response, and their role in vascular dysfunction. We will also address the potential underlying mechanisms, including the possibility that SPOs are among the causes of vascular injury in CVD associated with cognitive decline. By revealing common mechanistic underpinnings of AD and CVD, we hope that novel experimental therapeutics can be designed to reduce the burden of these devastating diseases. Graphical abstract Alzheimer's disease (AD) pathology leads to the release of Aβ peptides, and their accumulation in the peripheral organs has varying effects on various components of the cardiovascular system including endoplasmic reticulum (ER) stress and vascular damage. Image created with BioRender.com.
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Affiliation(s)
- Emily W Waigi
- Cardiovascular Translational Research Cententer (CTRC), Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC, USA
| | - R Clinton Webb
- Cardiovascular Translational Research Cententer (CTRC), Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC, USA
- Biomedical Engineering Program, Univeristy of South Carolina, Columbia, SC, USA
| | - Melissa A Moss
- Biomedical Engineering Program, Univeristy of South Carolina, Columbia, SC, USA
- Department of Chemical Engineering, University of South Carolina, Columbia, SC, USA
| | - Mark J Uline
- Biomedical Engineering Program, Univeristy of South Carolina, Columbia, SC, USA
- Department of Chemical Engineering, University of South Carolina, Columbia, SC, USA
| | - Cameron G McCarthy
- Cardiovascular Translational Research Cententer (CTRC), Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC, USA
- Biomedical Engineering Program, Univeristy of South Carolina, Columbia, SC, USA
| | - Camilla Ferreira Wenceslau
- Cardiovascular Translational Research Cententer (CTRC), Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC, USA.
- Biomedical Engineering Program, Univeristy of South Carolina, Columbia, SC, USA.
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4
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Sasahara T, Satomura K, Tada M, Kakita A, Hoshi M. Alzheimer's Aβ assembly binds sodium pump and blocks endothelial NOS activity via ROS-PKC pathway in brain vascular endothelial cells. iScience 2021; 24:102936. [PMID: 34458695 PMCID: PMC8379508 DOI: 10.1016/j.isci.2021.102936] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 06/24/2021] [Accepted: 07/29/2021] [Indexed: 01/12/2023] Open
Abstract
Amyloid β-protein (Aβ) may contribute to worsening of Alzheimer's disease (AD) through vascular dysfunction, but the molecular mechanism involved is unknown. Using ex vivo blood vessels and primary endothelial cells from human brain microvessels, we show that patient-derived Aβ assemblies, termed amylospheroids (ASPD), exist on the microvascular surface in patients' brains and inhibit vasorelaxation through binding to the α3 subunit of sodium, potassium-ATPase (NAKα3) in caveolae on endothelial cells. Interestingly, NAKα3 is also the toxic target of ASPD in neurons. ASPD-NAKα3 interaction elicits neurodegeneration through calcium overload in neurons, while the same interaction suppresses vasorelaxation by increasing the inactive form of endothelial nitric oxide synthase (eNOS) in endothelial cells via mitochondrial ROS and protein kinase C, independently of the physiological relaxation system. Thus, ASPD may contribute to both neuronal and vascular pathologies through binding to NAKα3. Therefore, blocking the ASPD-NAKα3 interaction may be a useful target for AD therapy.
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Affiliation(s)
- Tomoya Sasahara
- Department for Brain and Neurodegenerative Disease Research, Institute of Biomedical Research and Innovation, Foundation for Biomedical Research and Innovation at Kobe, CLIK 6F 6-3-7 Minatojima-Minamimachi, Chuo-ku, Kobe, 650-0047, Japan
- TAO Health Life Pharma Co., Ltd., Med-Pharma Collaboration Bldg, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto, 606-8501, Japan
| | - Kaori Satomura
- Department for Brain and Neurodegenerative Disease Research, Institute of Biomedical Research and Innovation, Foundation for Biomedical Research and Innovation at Kobe, CLIK 6F 6-3-7 Minatojima-Minamimachi, Chuo-ku, Kobe, 650-0047, Japan
- TAO Health Life Pharma Co., Ltd., Med-Pharma Collaboration Bldg, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto, 606-8501, Japan
| | - Mari Tada
- Department of Pathology, Brain Research Institute, Niigata University, Niigata, 951-8585, Japan
| | - Akiyoshi Kakita
- Department of Pathology, Brain Research Institute, Niigata University, Niigata, 951-8585, Japan
| | - Minako Hoshi
- Department for Brain and Neurodegenerative Disease Research, Institute of Biomedical Research and Innovation, Foundation for Biomedical Research and Innovation at Kobe, CLIK 6F 6-3-7 Minatojima-Minamimachi, Chuo-ku, Kobe, 650-0047, Japan
- Department of Anatomy and Developmental Biology, Graduate School of Medicine, Kyoto University, Kyoto, 606-8501, Japan
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5
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Liu D, Ahmet I, Griess B, Tweedie D, Greig NH, Mattson MP. Age-related impairment of cerebral blood flow response to K ATP channel opener in Alzheimer's disease mice with presenilin-1 mutation. J Cereb Blood Flow Metab 2021; 41:1579-1591. [PMID: 33203296 PMCID: PMC8221766 DOI: 10.1177/0271678x20964233] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Local cerebral blood flow (CBF) responses to neuronal activity are essential for cognition and impaired CBF responses occur in Alzheimer's disease (AD). In this study, regional CBF (rCBF) responses to the KATP channel opener diazoxide were investigated in 3xTgAD, WT and mutant Presenilin 1(PS1M146V) mice from three age groups using Laser-Doppler flowmetry. The rCBF response was reduced early in young 3xTgAD mice and almost absent in old 3xTgAD mice, up to 30%-40% reduction with altered CBF velocity and mean arterial pressure versus WT mice. The impaired rCBF response in 3xTgAD mice was associated with progression of AD pathology, characterized by deposition of intracellular and vascular amyloid-β (Aβ) oligomers, senile plaques and tau pathology. The nitric oxide synthase (NOS) inhibitor Nω-nitro-L-arginine abolished rCBF response to diazoxide suggesting NO was involved in the mediation of vasorelaxation. Levels of phosphor-eNOS (Ser1177) diminished in 3xTgAD brains with age, while the rCBF response to the NO donor sodium nitroprusside remained. In PS1M146V mice, the rCBF response to dizoxide reduced and high molecular weight Abeta oligomers were increased indicating PS1M146V contributed to the dysregulation of rCBF response in AD mice. Our study revealed an Aβ oligomer-associated compromise of cerebrovascular function in rCBF response to diazoxide in AD mice with PS1M146V mutation.
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Affiliation(s)
- Dong Liu
- Drug Design & Development Section, Translational Gerontology Branch, National Institute on Aging Intramural Research Program, Baltimore, MD, USA.,Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, MD, USA
| | - Ismayil Ahmet
- Laboratory of Cardiovascular Science, National Institute on Aging Intramural Research Program, Baltimore, MD, USA
| | - Brandon Griess
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, MD, USA
| | - David Tweedie
- Drug Design & Development Section, Translational Gerontology Branch, National Institute on Aging Intramural Research Program, Baltimore, MD, USA
| | - Nigel H Greig
- Drug Design & Development Section, Translational Gerontology Branch, National Institute on Aging Intramural Research Program, Baltimore, MD, USA
| | - Mark P Mattson
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, MD, USA.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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6
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Meakin PJ, Coull BM, Tuharska Z, McCaffery C, Akoumianakis I, Antoniades C, Brown J, Griffin KJ, Platt F, Ozber CH, Yuldasheva NY, Makava N, Skromna A, Prescott A, McNeilly AD, Siddiqui M, Palmer CN, Khan F, Ashford ML. Elevated circulating amyloid concentrations in obesity and diabetes promote vascular dysfunction. J Clin Invest 2021; 130:4104-4117. [PMID: 32407295 PMCID: PMC7410081 DOI: 10.1172/jci122237] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 04/29/2020] [Indexed: 12/11/2022] Open
Abstract
Diabetes, obesity, and Alzheimer’s disease (AD) are associated with vascular complications and impaired nitric oxide (NO) production. Furthermore, increased β-site amyloid precursor protein–cleaving (APP-cleaving) enzyme 1 (BACE1), APP, and β-amyloid (Aβ) are linked with vascular disease development and increased BACE1 and Aβ accompany hyperglycemia and hyperlipidemia. However, the causal relationship between obesity and diabetes, increased Aβ, and vascular dysfunction is unclear. We report that diet-induced obesity (DIO) in mice increased plasma and vascular Aβ42 that correlated with decreased NO bioavailability, endothelial dysfunction, and increased blood pressure. Genetic or pharmacological reduction of BACE1 activity and Aβ42 prevented and reversed, respectively, these outcomes. In contrast, expression of human mutant APP in mice or Aβ42 infusion into control diet–fed mice to mimic obese levels impaired NO production, vascular relaxation, and raised blood pressure. In humans, increased plasma Aβ42 correlated with diabetes and endothelial dysfunction. Mechanistically, higher Aβ42 reduced endothelial NO synthase (eNOS), cyclic GMP (cGMP), and protein kinase G (PKG) activity independently of diet, whereas endothelin-1 was increased by diet and Aβ42. Lowering Aβ42 reversed the DIO deficit in the eNOS/cGMP/PKG pathway and decreased endothelin-1. Our findings suggest that BACE1 inhibitors may have therapeutic value in the treatment of vascular disease associated with diabetes.
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Affiliation(s)
- Paul J Meakin
- Division of Systems Medicine, School of Medicine, Ninewells Hospital and Medical School, Dundee, United Kingdom.,Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, United Kingdom
| | - Bethany M Coull
- Division of Systems Medicine, School of Medicine, Ninewells Hospital and Medical School, Dundee, United Kingdom
| | - Zofia Tuharska
- Division of Systems Medicine, School of Medicine, Ninewells Hospital and Medical School, Dundee, United Kingdom
| | - Christopher McCaffery
- Division of Systems Medicine, School of Medicine, Ninewells Hospital and Medical School, Dundee, United Kingdom
| | - Ioannis Akoumianakis
- Cardiovascular Medicine Division, Level 6 West Wing, John Radcliffe Hospital, Headington, Oxford, United Kingdom
| | - Charalambos Antoniades
- Cardiovascular Medicine Division, Level 6 West Wing, John Radcliffe Hospital, Headington, Oxford, United Kingdom
| | - Jane Brown
- Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, United Kingdom
| | - Kathryn J Griffin
- Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, United Kingdom
| | - Fiona Platt
- Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, United Kingdom
| | - Claire H Ozber
- Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, United Kingdom
| | - Nadira Y Yuldasheva
- Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, United Kingdom
| | - Natallia Makava
- Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, United Kingdom
| | - Anna Skromna
- Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, United Kingdom
| | - Alan Prescott
- School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Alison D McNeilly
- Division of Systems Medicine, School of Medicine, Ninewells Hospital and Medical School, Dundee, United Kingdom
| | - Moneeza Siddiqui
- Division of Population Health & Genomics, School of Medicine, Ninewells Hospital and Medical School, Dundee, United Kingdom
| | - Colin Na Palmer
- Division of Population Health & Genomics, School of Medicine, Ninewells Hospital and Medical School, Dundee, United Kingdom
| | - Faisel Khan
- Division of Systems Medicine, School of Medicine, Ninewells Hospital and Medical School, Dundee, United Kingdom
| | - Michael Lj Ashford
- Division of Systems Medicine, School of Medicine, Ninewells Hospital and Medical School, Dundee, United Kingdom
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7
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Zuccarello E, Acquarone E, Calcagno E, Argyrousi EK, Deng SX, Landry DW, Arancio O, Fiorito J. Development of novel phosphodiesterase 5 inhibitors for the therapy of Alzheimer's disease. Biochem Pharmacol 2020; 176:113818. [PMID: 31978378 DOI: 10.1016/j.bcp.2020.113818] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 01/14/2020] [Indexed: 12/13/2022]
Abstract
Nitric oxide (NO) is a gaseous molecule that plays a multifactorial role in several cellular processes. In the central nervous system, the NO dual nature in neuroprotection and neurotoxicity has been explored to unveil its involvement in Alzheimer's disease (AD). A growing body of research shows that the activation of the NO signaling pathway leading to the phosphorylation of the transcription factor cyclic adenine monophosphate responsive element binding protein (CREB) (so-called NO/cGMP/PKG/CREB signaling pathway) ameliorates altered neuroplasticity and memory deficits in AD animal models. In addition to NO donors, several other pharmacological agents, such as phosphodiesterase 5 (PDE5) inhibitors have been used to activate the pathway and rescue memory disorders. PDE5 inhibitors, including sildenafil, tadalafil and vardenafil, are marketed for the treatment of erectile dysfunction and arterial pulmonary hypertension due to their vasodilatory properties. The ability of PDE5 inhibitors to interfere with the NO/cGMP/PKG/CREB signaling pathway by increasing the levels of cGMP has prompted the hypothesis that PDE5 inhibition might be used as an effective therapeutic strategy for the treatment of AD. To this end, newly designed PDE5 inhibitors belonging to different chemical classes with improved pharmacologic profile (e.g. higher potency, improved selectivity, and blood-brain barrier penetration) have been synthesized and evaluated in several animal models of AD. In addition, recent medicinal chemistry effort has led to the development of agents concurrently acting on the PDE5 enzyme and a second target involved in AD. Both marketed and investigational PDE5 inhibitors have shown to reverse cognitive defects in young and aged wild type mice as well as transgenic mouse models of AD and tauopathy using a variety of behavioral tasks. These studies confirmed the therapeutic potential of PDE5 inhibitors as cognitive enhancers. However, clinical studies assessing cognitive functions using marketed PDE5 inhibitors have not been conclusive. Drug discovery efforts by our group and others are currently directed towards the development of novel PDE5 inhibitors tailored to AD with improved pharmacodynamic and pharmacokinetic properties. In summary, the present perspective reports an overview of the correlation between the NO signaling and AD, as well as an outline of the PDE5 inhibitors used as an alternative approach in altering the NO pathway leading to an improvement of learning and memory. The last two sections describe the preclinical and clinical evaluation of PDE5 inhibitors for the treatment of AD, providing a comprehensive analysis of the current status of the AD drug discovery efforts involving PDE5 as a new therapeutic target.
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Affiliation(s)
- Elisa Zuccarello
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY, United States
| | - Erica Acquarone
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY, United States
| | - Elisa Calcagno
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY, United States
| | - Elentina K Argyrousi
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY, United States
| | - Shi-Xian Deng
- Department of Medicine, Columbia University, New York, NY, United States
| | - Donald W Landry
- Department of Medicine, Columbia University, New York, NY, United States
| | - Ottavio Arancio
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY, United States; Department of Medicine, Columbia University, New York, NY, United States; Department of Pathology and Cell Biology, Columbia University, New York, NY, United States.
| | - Jole Fiorito
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY, United States; Department of Biological and Chemical Sciences, New York Institute of Technology, Old Westbury, NY, United States.
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8
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Abstract
Vascular endothelial growth factor (VEGF) is a potent angiogenic factor. Despite upregulation of VEGF in the brain in Alzheimer's disease (AD), probably in response to amyloid-β, vasoconstriction, and tissue hypoxia, there is no consequent increase in microvessel density. VEGF binds to and activates VEGF receptor 2 (VEGFR2), but also binds to VEGF receptor 1 (VEGFR1), which exists in less-active membrane-bound and inactive soluble (sVEGFR1) forms and inhibits pro-angiogenic signaling. We have investigated whether altered expression of VEGF receptors might account for the lack of angiogenic response to VEGF in AD. We assessed the cellular distribution and protein level of VEGFR1 and VEGFR2 in parietal cortex from 50 AD and 36 age-matched control brains, and related the findings to measurements of VEGF and von Willebrand factor level (a marker of microvessel density) in the same tissue samples. VEGFR2 was expressed by neurons, astrocytes and endothelial cells. VEGFR1 was expressed predominantly neuronally and was significantly reduced in AD (p = 0.02). Western blot analysis on a subset of brains showed reduction in VEGFR1:sVEGFR1 in AD (p = 0.046). The lack of angiogenesis despite cerebral hypoperfusion in AD is not explained by altered expression of VEGFR2 or total VEGFR1; indeed, the downregulation of VEGFR1 may represent a pro-angiogenic response to the hypoperfusion. However, the relative increase in sVEGFR1 would be expected to have an anti-angiogenic effect which may be a factor in AD.
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Affiliation(s)
- Rachel Harris
- Institute of Clinical Neurosciences, University of Bristol, School of Medicine, Level 2 Learning and Research, Southmead Hospital, Bristol, UK
| | - James Scott Miners
- Institute of Clinical Neurosciences, University of Bristol, School of Medicine, Level 2 Learning and Research, Southmead Hospital, Bristol, UK
| | - Shelley Allen
- Institute of Clinical Neurosciences, University of Bristol, School of Medicine, Level 2 Learning and Research, Southmead Hospital, Bristol, UK
| | - Seth Love
- Institute of Clinical Neurosciences, University of Bristol, School of Medicine, Level 2 Learning and Research, Southmead Hospital, Bristol, UK
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9
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Roberts AM, Jagadapillai R, Vaishnav RA, Friedland RP, Drinovac R, Lin X, Gozal E. Increased pulmonary arteriolar tone associated with lung oxidative stress and nitric oxide in a mouse model of Alzheimer's disease. Physiol Rep 2017; 4:4/17/e12953. [PMID: 27604401 PMCID: PMC5027359 DOI: 10.14814/phy2.12953] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 08/07/2016] [Indexed: 12/18/2022] Open
Abstract
Vascular dysfunction and decreased cerebral blood flow are linked to Alzheimer's disease (AD). Loss of endothelial nitric oxide (NO) and oxidative stress in human cerebrovascular endothelium increase expression of amyloid precursor protein (APP) and enhance production of the Aβ peptide, suggesting that loss of endothelial NO contributes to AD pathology. We hypothesize that decreased systemic NO bioavailability in AD may also impact lung microcirculation and induce pulmonary endothelial dysfunction. The acute effect of NO synthase (NOS) inhibition on pulmonary arteriolar tone was assessed in a transgenic mouse model (TgAD) of AD (C57BL/6‐Tg(Thy1‐APPSwDutIowa)BWevn/Mmjax) and age‐matched wild‐type controls (C57BL/6J). Arteriolar diameters were measured before and after the administration of the NOS inhibitor, L‐NAME. Lung superoxide formation (DHE) and formation of nitrotyrosine (3‐NT) were assessed as indicators of oxidative stress, inducible NOS (iNOS) and tumor necrosis factor alpha (TNF‐α) expression as indicators of inflammation. Administration of L‐NAME caused either significant pulmonary arteriolar constriction or no change from baseline tone in wild‐type (WT) mice, and significant arteriolar dilation in TgAD mice. DHE, 3‐NT, TNF‐α, and iNOS expression were higher in TgAD lung tissue, compared to WT mice. These data suggest L‐NAME could induce increased pulmonary arteriolar tone in WT mice from loss of bioavailable NO. In contrast, NOS inhibition with L‐NAME had a vasodilator effect in TgAD mice, potentially caused by decreased reactive nitrogen species formation, while significant oxidative stress and inflammation were present. We conclude that AD may increase pulmonary microvascular tone as a result of loss of bioavailable NO and increased oxidative stress. Our findings suggest that AD may have systemic microvascular implications beyond central neural control mechanisms.
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Affiliation(s)
- Andrew M Roberts
- Department of Physiology, School of Medicine University of Louisville, Louisville, Kentucky, 40202 Department of Pediatrics, School of Medicine University of Louisville, Louisville, Kentucky, 40202
| | - Rekha Jagadapillai
- Department of Pediatrics, School of Medicine University of Louisville, Louisville, Kentucky, 40202
| | - Radhika A Vaishnav
- Department of Physiology, School of Medicine University of Louisville, Louisville, Kentucky, 40202 Department of Neurology, School of Medicine University of Louisville, Louisville, Kentucky, 40202
| | - Robert P Friedland
- Department of Neurology, School of Medicine University of Louisville, Louisville, Kentucky, 40202 Department of Anatomical Sciences and Neurobiology, School of Medicine University of Louisville, Louisville, Kentucky, 40202
| | - Robert Drinovac
- Department of Physiology, School of Medicine University of Louisville, Louisville, Kentucky, 40202
| | - Xingyu Lin
- Department of Pediatrics, School of Medicine University of Louisville, Louisville, Kentucky, 40202 Department of Thoracic Surgery, the First Hospital of Jilin University, Changchun, China
| | - Evelyne Gozal
- Department of Physiology, School of Medicine University of Louisville, Louisville, Kentucky, 40202 Department of Pediatrics, School of Medicine University of Louisville, Louisville, Kentucky, 40202
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10
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d'Uscio LV, He T, Katusic ZS. Expression and Processing of Amyloid Precursor Protein in Vascular Endothelium. Physiology (Bethesda) 2017; 32:20-32. [PMID: 27927802 DOI: 10.1152/physiol.00021.2016] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Amyloid precursor protein (APP) is evolutionary conserved protein expressed in endothelial cells of cerebral and peripheral arteries. In this review, we discuss mechanisms responsible for expression and proteolytic cleavage of APP in endothelial cells. We focus on physiological and pathological implications of APP expression in vascular endothelium.
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Affiliation(s)
- Livius V d'Uscio
- Departments of Anesthesiology and Molecular Pharmacology & Experimental Therapeutics, Mayo Clinic College of Medicine, Rochester, Minnesota
| | - Tongrong He
- Departments of Anesthesiology and Molecular Pharmacology & Experimental Therapeutics, Mayo Clinic College of Medicine, Rochester, Minnesota
| | - Zvonimir S Katusic
- Departments of Anesthesiology and Molecular Pharmacology & Experimental Therapeutics, Mayo Clinic College of Medicine, Rochester, Minnesota
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11
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Lai AY, McLaurin J. Rho-associated protein kinases as therapeutic targets for both vascular and parenchymal pathologies in Alzheimer's disease. J Neurochem 2017; 144:659-668. [PMID: 28722749 DOI: 10.1111/jnc.14130] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Revised: 06/21/2017] [Accepted: 07/14/2017] [Indexed: 12/30/2022]
Abstract
The causes of late-onset Alzheimer's disease are unclear and likely multifactorial. Rho-associated protein kinases (ROCKs) are ubiquitously expressed signaling messengers that mediate a wide array of cellular processes. Interestingly, they play an important role in several vascular and brain pathologies implicated in Alzheimer's etiology, including hypertension, hypercholesterolemia, blood-brain barrier disruption, oxidative stress, deposition of vascular and parenchymal amyloid-beta peptides, tau hyperphosphorylation, and cognitive decline. The current review summarizes the functions of ROCKs with respect to the various risk factors and pathologies on both sides of the blood-brain barrier and present support for targeting ROCK signaling as a multifactorial and multi-effect approach for the prevention and amelioration of late-onset Alzheimer's disease. This article is part of the Special Issue "Vascular Dementia".
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Affiliation(s)
- Aaron Y Lai
- Biological Sciences Platform, Sunnybrook Research Institute, Toronto, Ontario, Canada
| | - JoAnne McLaurin
- Biological Sciences Platform, Sunnybrook Research Institute, Toronto, Ontario, Canada.,Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
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12
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Carelli-Alinovi C, Dinarelli S, Girasole M, Misiti F. Vascular dysfunction-associated with Alzheimer’s disease. Clin Hemorheol Microcirc 2017; 64:679-687. [DOI: 10.3233/ch-168047] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Cristiana Carelli-Alinovi
- Institute of Biochemistry and Clinical Biochemistry, Catholic University, School of Medicine, Rome, Italy
| | - Simone Dinarelli
- Institute for the Structure of the Matter (ISM), National Research Council (CNR), Rome, Italy
| | - Marco Girasole
- Institute for the Structure of the Matter (ISM), National Research Council (CNR), Rome, Italy
| | - Francesco Misiti
- Department of Human Sciences, Society and Health, University of Cassino and Southern Latium, V. S. Angelo Th., Polo Didattico della Folcara, Cassino (FR), Italy
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13
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Gupta V, Gupta VB, Chitranshi N, Gangoda S, Vander Wall R, Abbasi M, Golzan M, Dheer Y, Shah T, Avolio A, Chung R, Martins R, Graham S. One protein, multiple pathologies: multifaceted involvement of amyloid β in neurodegenerative disorders of the brain and retina. Cell Mol Life Sci 2016; 73:4279-4297. [PMID: 27333888 PMCID: PMC11108534 DOI: 10.1007/s00018-016-2295-x] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Revised: 06/14/2016] [Accepted: 06/15/2016] [Indexed: 01/18/2023]
Abstract
Accumulation of amyloid β (Aβ) and its aggregates in the ageing central nervous system is regarded synonymous to Alzheimer's disease (AD) pathology. Despite unquestionable advances in mechanistic and diagnostic aspects of the disease understanding, the primary cause of Aβ accumulation as well as its in vivo roles remains elusive; nonetheless, the majority of the efforts to address pathological mechanisms for therapeutic development are focused towards moderating Aβ accumulation in the brain. More recently, Aβ deposition has been identified in the eye and is linked with distinct age-related diseases including age-related macular degeneration, glaucoma as well as AD. Awareness of the Aβ accumulation in these markedly different degenerative disorders has led to an increasing body of work exploring overlapping mechanisms, a prospective biomarker role for Aβ and the potential to use retina as a model for brain related neurodegenerative disorders. Here, we present an integrated view of current understanding of the retinal Aβ deposition discussing the accumulation mechanisms, anticipated impacts and outlining ameliorative approaches that can be extrapolated to the retina for potential therapeutic benefits. Further longitudinal investigations in humans and animal models will determine retinal Aβ association as a potential pathognomonic, diagnostic or prognostic biomarker.
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Affiliation(s)
- Vivek Gupta
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Veer B Gupta
- School of Medical Sciences, Edith Cowan University, Perth, Australia.
| | - Nitin Chitranshi
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Sumudu Gangoda
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Roshana Vander Wall
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Mojdeh Abbasi
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Mojtaba Golzan
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Yogita Dheer
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Tejal Shah
- School of Medical Sciences, Edith Cowan University, Perth, Australia
| | - Alberto Avolio
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Roger Chung
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Ralph Martins
- School of Medical Sciences, Edith Cowan University, Perth, Australia
| | - Stuart Graham
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
- Save Sight Institute, Sydney University, Sydney, Australia
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14
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Love S, Miners J. Cerebral Hypoperfusion and the Energy Deficit in Alzheimer's Disease. Brain Pathol 2016; 26:607-17. [PMID: 27327656 PMCID: PMC8028913 DOI: 10.1111/bpa.12401] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Revised: 06/21/2016] [Accepted: 05/25/2016] [Indexed: 12/19/2022] Open
Abstract
There is a perfusion deficit in Alzheimer's disease (AD), commencing in the precuneus and spreading to other parts of the cerebral cortex. The deficit anticipates the development of dementia, contributes to brain damage, and is caused by both functional and structural abnormalities of the cerebral vasculature. Most of the abnormalities are probably secondary to the accumulation of Aβ but the consequent hypoperfusion may, in turn, increase Aβ production. In the early stages of disease, abnormalities that cause vasoconstriction predominate. These include cholinergic vascular denervation, inhibition of endothelial nitric oxide synthase, increased production of endothelin-1 production and possibly also of angiotensin II. Patients with AD also have an increased prevalence of structural disease of cerebral microvessels, particularly CAA and capillary damage, and particularly in the later stages of disease these are likely to make an important contribution to the cerebral hypoperfusion. The metabolic abnormalities that cause early vascular dysfunction offer several targets for therapeutic intervention. However, for intervention to be effective it probably needs to be early. Prolonged cerebral hypoperfusion may induce compensatory circulatory changes that are themselves damaging, including hypertension and small vessel disease. This has implications for the use of antihypertensive drugs once there is accumulation of Aβ within the brain.
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Affiliation(s)
- Seth Love
- Dementia Research Group, Institute of Clinical Neurosciences, School of Clinical SciencesUniversity of BristolBristolUnited Kingom
| | - J.Scott Miners
- Dementia Research Group, Institute of Clinical Neurosciences, School of Clinical SciencesUniversity of BristolBristolUnited Kingom
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15
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Administration of tauroursodeoxycholic acid prevents endothelial dysfunction caused by an oral glucose load. Clin Sci (Lond) 2016; 130:1881-8. [PMID: 27503949 DOI: 10.1042/cs20160501] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 08/08/2016] [Indexed: 12/13/2022]
Abstract
Postprandial hyperglycaemia leads to a transient impairment in endothelial function; however, the mechanisms remain largely unknown. Previous work in cell culture models demonstrate that high glucose results in endoplasmic reticulum (ER) stress and, in animal studies, ER stress has been implicated as a cause of endothelial dysfunction. In the present study, we tested the hypothesis that acute oral administration of tauroursodeoxycholic acid (TUDCA, 1500 mg), a chemical chaperone known to alleviate ER stress, would prevent hyperglycaemia-induced endothelial dysfunction. In 12 young healthy subjects (seven men, five women), brachial artery flow-mediated dilation (FMD) was assessed at baseline, and at 60 and 120 min after an oral glucose challenge. Subjects were tested on two separate visits in a single-blind randomized cross-over design: after oral ingestion of TUDCA or placebo capsules. FMD was reduced from baseline during hyperglycaemia under the placebo condition (-32% at 60 min and -28% at 120 min post oral glucose load; P<0.05 from baseline) but not under the TUDCA condition (-4% at 60 min and +0.3% at 120 min post oral glucose load; P>0.05 from baseline). Postprandial plasma glucose and insulin were not altered by TUDCA ingestion. Plasma oxidative stress markers 3-nitrotyrosine and thiobarbituric acid reactive substance (TBARS) remained unaltered throughout the oral glucose challenge in both conditions. These results suggest that hyperglycaemia-induced endothelial dysfunction can be mitigated by oral administration of TUDCA, thus supporting the hypothesis that ER stress may contribute to endothelial dysfunction during postprandial hyperglycaemia.
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16
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Di Marco LY, Farkas E, Martin C, Venneri A, Frangi AF. Is Vasomotion in Cerebral Arteries Impaired in Alzheimer's Disease? J Alzheimers Dis 2016; 46:35-53. [PMID: 25720414 PMCID: PMC4878307 DOI: 10.3233/jad-142976] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
A substantial body of evidence supports the hypothesis of a vascular component in the pathogenesis of Alzheimer’s disease (AD). Cerebral hypoperfusion and blood-brain barrier dysfunction have been indicated as key elements of this pathway. Cerebral amyloid angiopathy (CAA) is a cerebrovascular disorder, frequent in AD, characterized by the accumulation of amyloid-β (Aβ) peptide in cerebral blood vessel walls. CAA is associated with loss of vascular integrity, resulting in impaired regulation of cerebral circulation, and increased susceptibility to cerebral ischemia, microhemorrhages, and white matter damage. Vasomotion— the spontaneous rhythmic modulation of arterial diameter, typically observed in arteries/arterioles in various vascular beds including the brain— is thought to participate in tissue perfusion and oxygen delivery regulation. Vasomotion is impaired in adverse conditions such as hypoperfusion and hypoxia. The perivascular and glymphatic pathways of Aβ clearance are thought to be driven by the systolic pulse. Vasomotion produces diameter changes of comparable amplitude, however at lower rates, and could contribute to these mechanisms of Aβ clearance. In spite of potential clinical interest, studies addressing cerebral vasomotion in the context of AD/CAA are limited. This study reviews the current literature on vasomotion, and hypothesizes potential paths implicating impaired cerebral vasomotion in AD/CAA. Aβ and oxidative stress cause vascular tone dysregulation through direct effects on vascular cells, and indirect effects mediated by impaired neurovascular coupling. Vascular tone dysregulation is further aggravated by cholinergic deficit and results in depressed cerebrovascular reactivity and (possibly) impaired vasomotion, aggravating regional hypoperfusion and promoting further Aβ and oxidative stress accumulation.
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Affiliation(s)
- Luigi Yuri Di Marco
- Centre for Computational Imaging and Simulation Technologies in Biomedicine (CISTIB), Department of Electronic and Electrical Engineering, University of Sheffield, Sheffield, UK
| | - Eszter Farkas
- Department of Medical Physics and Informatics, Faculty of Medicine and Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
| | - Chris Martin
- Department of Psychology, University of Sheffield, Sheffield, UK
| | - Annalena Venneri
- Department of Neuroscience, University of Sheffield, Sheffield, UK.,IRCCS, Fondazione Ospedale S. Camillo, Venice, Italy
| | - Alejandro F Frangi
- Centre for Computational Imaging and Simulation Technologies in Biomedicine (CISTIB), Department of Electronic and Electrical Engineering, University of Sheffield, Sheffield, UK
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17
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Manukhina EB, Downey HF, Shi X, Mallet RT. Intermittent hypoxia training protects cerebrovascular function in Alzheimer's disease. Exp Biol Med (Maywood) 2016; 241:1351-63. [PMID: 27190276 DOI: 10.1177/1535370216649060] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Alzheimer's disease (AD) is a leading cause of death and disability among older adults. Modifiable vascular risk factors for AD (VRF) include obesity, hypertension, type 2 diabetes mellitus, sleep apnea, and metabolic syndrome. Here, interactions between cerebrovascular function and development of AD are reviewed, as are interventions to improve cerebral blood flow and reduce VRF. Atherosclerosis and small vessel cerebral disease impair metabolic regulation of cerebral blood flow and, along with microvascular rarefaction and altered trans-capillary exchange, create conditions favoring AD development. Although currently there are no definitive therapies for treatment or prevention of AD, reduction of VRFs lowers the risk for cognitive decline. There is increasing evidence that brief repeated exposures to moderate hypoxia, i.e. intermittent hypoxic training (IHT), improve cerebral vascular function and reduce VRFs including systemic hypertension, cardiac arrhythmias, and mental stress. In experimental AD, IHT nearly prevented endothelial dysfunction of both cerebral and extra-cerebral blood vessels, rarefaction of the brain vascular network, and the loss of neurons in the brain cortex. Associated with these vasoprotective effects, IHT improved memory and lessened AD pathology. IHT increases endothelial production of nitric oxide (NO), thereby increasing regional cerebral blood flow and augmenting the vaso- and neuroprotective effects of endothelial NO. On the other hand, in AD excessive production of NO in microglia, astrocytes, and cortical neurons generates neurotoxic peroxynitrite. IHT enhances storage of excessive NO in the form of S-nitrosothiols and dinitrosyl iron complexes. Oxidative stress plays a pivotal role in the pathogenesis of AD, and IHT reduces oxidative stress in a number of experimental pathologies. Beneficial effects of IHT in experimental neuropathologies other than AD, including dyscirculatory encephalopathy, ischemic stroke injury, audiogenic epilepsy, spinal cord injury, and alcohol withdrawal stress have also been reported. Further research on the potential benefits of IHT in AD and other brain pathologies is warranted.
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Affiliation(s)
- Eugenia B Manukhina
- University of North Texas Health Science Center, Fort Worth, TX 76107-2699, USA Institute of General Pathology and Pathophysiology, Moscow 125315, Russian Federation
| | - H Fred Downey
- University of North Texas Health Science Center, Fort Worth, TX 76107-2699, USA
| | - Xiangrong Shi
- University of North Texas Health Science Center, Fort Worth, TX 76107-2699, USA
| | - Robert T Mallet
- University of North Texas Health Science Center, Fort Worth, TX 76107-2699, USA
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18
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Love S, Miners JS. Cerebrovascular disease in ageing and Alzheimer's disease. Acta Neuropathol 2016; 131:645-58. [PMID: 26711459 PMCID: PMC4835514 DOI: 10.1007/s00401-015-1522-0] [Citation(s) in RCA: 200] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Revised: 12/03/2015] [Accepted: 12/07/2015] [Indexed: 12/14/2022]
Abstract
Cerebrovascular disease (CVD) and Alzheimer’s disease (AD) have more in common than their association with ageing. They share risk factors and overlap neuropathologically. Most patients with AD have Aβ amyloid angiopathy and degenerative changes affecting capillaries, and many have ischaemic parenchymal abnormalities. Structural vascular disease contributes to the ischaemic abnormalities in some patients with AD. However, the stereotyped progression of hypoperfusion in this disease, affecting first the precuneus and cingulate gyrus, then the frontal and temporal cortex and lastly the occipital cortex, suggests that other factors are more important, particularly in early disease. Whilst demand for oxygen and glucose falls in late disease, functional MRI, near infrared spectroscopy to measure the saturation of haemoglobin by oxygen, and biochemical analysis of myelin proteins with differential susceptibility to reduced oxygenation have all shown that the reduction in blood flow in AD is primarily a problem of inadequate blood supply, not reduced metabolic demand. Increasing evidence points to non-structural vascular dysfunction rather than structural abnormalities of vessel walls as the main cause of cerebral hypoperfusion in AD. Several mediators are probably responsible. One that is emerging as a major contributor is the vasoconstrictor endothelin-1 (EDN1). Whilst there is clearly an additive component to the clinical and pathological effects of hypoperfusion and AD, experimental and clinical observations suggest that the disease processes also interact mechanistically at a cellular level in a manner that exacerbates both. The elucidation of some of the mechanisms responsible for hypoperfusion in AD and for the interactions between CVD and AD has led to the identification of several novel therapeutic approaches that have the potential to ameliorate ischaemic damage and slow the progression of neurodegenerative disease.
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Affiliation(s)
- Seth Love
- Institute of Clinical Neurosciences, School of Clinical Sciences, Learning and Research Level 2, Southmead Hospital, University of Bristol, Bristol, BS10 5NB, UK.
| | - J Scott Miners
- Institute of Clinical Neurosciences, School of Clinical Sciences, Learning and Research Level 2, Southmead Hospital, University of Bristol, Bristol, BS10 5NB, UK
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19
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Salmina AB, Komleva YK, Szijártó IA, Gorina YV, Lopatina OL, Gertsog GE, Filipovic MR, Gollasch M. H2S- and NO-Signaling Pathways in Alzheimer's Amyloid Vasculopathy: Synergism or Antagonism? Front Physiol 2015; 6:361. [PMID: 26696896 PMCID: PMC4675996 DOI: 10.3389/fphys.2015.00361] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Accepted: 11/16/2015] [Indexed: 12/02/2022] Open
Abstract
Alzheimer's type of neurodegeneration dramatically affects H2S and NO synthesis and interactions in the brain, which results in dysregulated vasomotor function, brain tissue hypoperfusion and hypoxia, development of perivascular inflammation, promotion of Aβ deposition, and impairment of neurogenesis/angiogenesis. H2S- and NO-signaling pathways have been described to offer protection against Alzheimer's amyloid vasculopathy and neurodegeneration. This review describes recent developments of the increasing relevance of H2S and NO in Alzheimer's disease (AD). More studies are however needed to fully determine their potential use as therapeutic targets in Alzheimer's and other forms of vascular dementia.
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Affiliation(s)
- Alla B. Salmina
- Department of Biochemistry, Medical, Pharmaceutical and Toxicological Chemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-YasenetskyKrasnoyarsk, Russia
| | - Yulia K. Komleva
- Department of Biochemistry, Medical, Pharmaceutical and Toxicological Chemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-YasenetskyKrasnoyarsk, Russia
| | - István A. Szijártó
- Experimental and Clinical Research Center, Charité - University Medicine Berlin and the Max Delbrück Center for Molecular MedicineBerlin, Germany
| | - Yana V. Gorina
- Department of Biochemistry, Medical, Pharmaceutical and Toxicological Chemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-YasenetskyKrasnoyarsk, Russia
| | - Olga L. Lopatina
- Department of Biochemistry, Medical, Pharmaceutical and Toxicological Chemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-YasenetskyKrasnoyarsk, Russia
| | - Galina E. Gertsog
- Department of Biochemistry, Medical, Pharmaceutical and Toxicological Chemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-YasenetskyKrasnoyarsk, Russia
| | - Milos R. Filipovic
- Department of Chemistry and Pharmacy, Friedrich-Alexander-University of Erlangen-NürnbergErlangen, Germany
| | - Maik Gollasch
- Experimental and Clinical Research Center, Charité - University Medicine Berlin and the Max Delbrück Center for Molecular MedicineBerlin, Germany
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20
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Miners JS, Palmer JC, Love S. Pathophysiology of Hypoperfusion of the Precuneus in Early Alzheimer's Disease. Brain Pathol 2015; 26:533-41. [PMID: 26452729 PMCID: PMC4982069 DOI: 10.1111/bpa.12331] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 10/05/2015] [Indexed: 12/17/2022] Open
Abstract
The earliest decline in cerebral perfusion in Alzheimer's disease (AD) is in the medial parietal cortex (precuneus). We have analyzed precuneus in post‐mortem tissue from 70 AD and 37 control brains to explore the pathophysiology of the hypoperfusion: the contribution of arteriolosclerotic small vessel disease (SVD) and cerebral amyloid angiopathy (CAA), and of the vasoconstrictors endothelin‐1 (EDN1) and angiotensin II (Ang II), and the association with Aβ. The myelin‐associated glycoprotein:proteolipid protein‐1 ratio (MAG:PLP1) was used as an indicator of oxygenation of the precuneus prior to death. MAG:PLP1 was reduced ∼50% in early AD (Braak stage III–IV). Although MAG:PLP1 remained low in advanced AD (stage V–VI), the reduction was less pronounced, possibly reflecting falling oxygen demand. Reduction in cortical MAG:PLP1 correlated with elevation in vascular endothelial growth factor (VEGF), another marker of hypoperfusion. Cortical MAG:PLP1 declined nonsignificantly with increasing SVD and CAA, but significantly with the concentration of EDN1, which was elevated approximately 75% in AD. In contrast, with reduction in cortical MAG:PLP1, Ang II level and angiotensin‐converting enzyme (ACE) activity declined, showing a normal physiological response to hypoperfusion. MAG:PLP1 was reduced in the parietal white matter (WM) in AD but here the decline correlated positively (ie, physiologically) with WM EDN1. However, the decline of MAG:PLP1 in the WM was associated with increasing cortical EDN1 and perhaps reflected vasoconstriction of perforating arterioles, which traverse the cortex to perfuse the WM. EDN1 in the cortex correlated highly significantly with both soluble and insoluble Aβ42, shown previously to upregulate neuronal endothelin‐converting enzyme‐2 (ECE2), but not with Aβ40. Our findings demonstrate reduced oxygenation of the precuneus in early AD and suggest that elevated EDN1, resulting from Aβ42‐mediated upregulation of ECE2, is a contributor.
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Affiliation(s)
- J Scott Miners
- Dementia Research Group, School of Clinical Sciences, Institute of Clinical Neurosciences, University of Bristol, Bristol, UK
| | - Jennifer C Palmer
- Dementia Research Group, School of Clinical Sciences, Institute of Clinical Neurosciences, University of Bristol, Bristol, UK
| | - Seth Love
- Dementia Research Group, School of Clinical Sciences, Institute of Clinical Neurosciences, University of Bristol, Bristol, UK
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21
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Morgese MG, Colaianna M, Mhillaj E, Zotti M, Schiavone S, D'Antonio P, Harkin A, Gigliucci V, Campolongo P, Trezza V, De Stradis A, Tucci P, Cuomo V, Trabace L. Soluble beta amyloid evokes alteration in brain norepinephrine levels: role of nitric oxide and interleukin-1. Front Neurosci 2015; 9:428. [PMID: 26594145 PMCID: PMC4633524 DOI: 10.3389/fnins.2015.00428] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 10/21/2015] [Indexed: 12/31/2022] Open
Abstract
Strong evidence showed neurotoxic properties of beta amyloid (Aβ) and its pivotal role in the Alzheimer's disease (AD) pathogenesis. Beside, experimental data suggest that Aβ may have physiological roles considering that such soluble peptide is produced and secreted during normal cellular activity. There is now suggestive evidence that neurodegenerative conditions, like AD, involve nitric oxide (NO) in their pathogenesis. Nitric oxide also possess potent neuromodulatory actions in brain regions, such as prefrontal cortex (PFC), hippocampus (HIPP), and nucleus accumbens (NAC). In the present study, we evaluated the effect of acute Aβ injection on norepinephrine (NE) content before and after pharmacological manipulations of nitrergic system in above mentioned areas. Moreover, effects of the peptide on NOS activity were evaluated. Our data showed that 2 h after i.c.v. soluble Aβ administration, NE concentrations were significantly increased in the considered areas along with increased iNOS activity. Pre-treatment with NOS inhibitors, 7-Nitroindazole (7-NI), and N6-(1-iminoethyl)-L-lysine-dihydrochloride (L-NIL), reversed Aβ-induced changes. Ultimately, pharmacological block of interleukin1 (IL-1) receptors prevented NE increase in all brain regions. Taken together our findings suggest that NO and IL-1 are critically involved in regional noradrenergic alterations induced by soluble Aβ injection.
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Affiliation(s)
- Maria G Morgese
- Department of Clinical and Experimental Medicine, University of Foggia Foggia, Italy
| | - Marilena Colaianna
- Department of Clinical and Experimental Medicine, University of Foggia Foggia, Italy ; Department of Pathology and Immunology, University of Geneva Geneva, Switzerland
| | - Emanuela Mhillaj
- Department of Clinical and Experimental Medicine, University of Foggia Foggia, Italy ; Department of Physiology and Pharmacology, La Sapienza, University of Rome Rome, Italy
| | - Margherita Zotti
- Department of Clinical and Experimental Medicine, University of Foggia Foggia, Italy
| | - Stefania Schiavone
- Department of Clinical and Experimental Medicine, University of Foggia Foggia, Italy
| | - Palma D'Antonio
- Department of Clinical and Experimental Medicine, University of Foggia Foggia, Italy
| | - Andrew Harkin
- Neuropsychopharmacology Research Group, School of Pharmacy and Pharmaceutical Sciences and Trinity College Institute of Neuroscience, Trinity College Dublin Dublin, Ireland
| | - Valentina Gigliucci
- Neuropsychopharmacology Research Group, School of Pharmacy and Pharmaceutical Sciences and Trinity College Institute of Neuroscience, Trinity College Dublin Dublin, Ireland
| | - Patrizia Campolongo
- Department of Physiology and Pharmacology, La Sapienza, University of Rome Rome, Italy
| | - Viviana Trezza
- Section of Biomedical Sciences and Technologies, Department of Science, University "Roma Tre," Rome, Italy
| | - Angelo De Stradis
- Department of Bio Agro-Food Sciences, The Institute of Sustainable Plant Protection, National Research Council Bari, Italy
| | - Paolo Tucci
- Department of Clinical and Experimental Medicine, University of Foggia Foggia, Italy
| | - Vincenzo Cuomo
- Department of Physiology and Pharmacology, La Sapienza, University of Rome Rome, Italy
| | - Luigia Trabace
- Department of Clinical and Experimental Medicine, University of Foggia Foggia, Italy
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22
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Di Marco LY, Venneri A, Farkas E, Evans PC, Marzo A, Frangi AF. Vascular dysfunction in the pathogenesis of Alzheimer's disease--A review of endothelium-mediated mechanisms and ensuing vicious circles. Neurobiol Dis 2015; 82:593-606. [PMID: 26311408 DOI: 10.1016/j.nbd.2015.08.014] [Citation(s) in RCA: 190] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Revised: 07/23/2015] [Accepted: 08/17/2015] [Indexed: 12/17/2022] Open
Abstract
Late-onset dementia is a major health concern in the ageing population. Alzheimer's disease (AD) accounts for the largest proportion (65-70%) of dementia cases in the older population. Despite considerable research effort, the pathogenesis of late-onset AD remains unclear. Substantial evidence suggests that the neurodegenerative process is initiated by chronic cerebral hypoperfusion (CCH) caused by ageing and cardiovascular conditions. CCH causes reduced oxygen, glucose and other nutrient supply to the brain, with direct damage not only to the parenchymal cells, but also to the blood-brain barrier (BBB), a key mediator of cerebral homeostasis. BBB dysfunction mediates the indirect neurotoxic effects of CCH by promoting oxidative stress, inflammation, paracellular permeability, and dysregulation of nitric oxide, a key regulator of regional blood flow. As such, BBB dysfunction mediates a vicious circle in which cerebral perfusion is reduced further and the neurodegenerative process is accelerated. Endothelial interaction with pericytes and astrocytes could also play a role in the process. Reciprocal interactions between vascular dysfunction and neurodegeneration could further contribute to the development of the disease. A comprehensive overview of the complex scenario of interacting endothelium-mediated processes is currently lacking, and could prospectively contribute to the identification of adequate therapeutic interventions. This study reviews the current literature of in vitro and ex vivo studies on endothelium-mediated mechanisms underlying vascular dysfunction in AD pathogenesis, with the aim of presenting a comprehensive overview of the complex network of causative relationships. Particular emphasis is given to vicious circles which can accelerate the process of neurovascular degeneration.
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Affiliation(s)
- Luigi Yuri Di Marco
- Centre for Computational Imaging and Simulation Technologies in Biomedicine (CISTIB), Department of Electronic and Electrical Engineering, University of Sheffield, Sheffield, UK.
| | - Annalena Venneri
- Department of Neuroscience, Medical School, University of Sheffield, Sheffield, UK; IRCCS San Camillo Foundation Hospital, Venice, Italy
| | - Eszter Farkas
- Department of Medical Physics and Informatics, Faculty of Medicine and Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
| | - Paul C Evans
- Department of Cardiovascular Science, Medical School, University of Sheffield, Sheffield, UK
| | - Alberto Marzo
- Centre for Computational Imaging and Simulation Technologies in Biomedicine (CISTIB), Department of Mechanical Engineering, University of Sheffield, Sheffield, UK
| | - Alejandro F Frangi
- Centre for Computational Imaging and Simulation Technologies in Biomedicine (CISTIB), Department of Electronic and Electrical Engineering, University of Sheffield, Sheffield, UK
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Proteome-wide characterization of signalling interactions in the hippocampal CA4/DG subfield of patients with Alzheimer's disease. Sci Rep 2015; 5:11138. [PMID: 26059363 PMCID: PMC4462342 DOI: 10.1038/srep11138] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 04/27/2015] [Indexed: 12/02/2022] Open
Abstract
Alzheimer’s disease (AD) is the most common form of dementia; however, mechanisms and biomarkers remain unclear. Here, we examined hippocampal CA4 and dentate gyrus subfields, which are less studied in the context of AD pathology, in post-mortem AD and control tissue to identify possible biomarkers. We performed mass spectrometry-based proteomic analysis combined with label-free quantification for identification of differentially expressed proteins. We identified 4,328 proteins, of which 113 showed more than 2-fold higher or lower expression in AD hippocampi than in control tissues. Five proteins were identified as putative AD biomarkers (MDH2, PCLO, TRRAP, YWHAZ, and MUC19 isoform 5) and were cross-validated by immunoblotting, selected reaction monitoring, and MALDI imaging. We also used a bioinformatics approach to examine upstream signalling interactions of the 113 regulated proteins. Five upstream signalling (IGF1, BDNF, ZAP70, MYC, and cyclosporin A) factors showed novel interactions in AD hippocampi. Taken together, these results demonstrate a novel platform that may provide new strategies for the early detection of AD and thus its diagnosis.
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Lamoke F, Mazzone V, Persichini T, Maraschi A, Harris MB, Venema RC, Colasanti M, Gliozzi M, Muscoli C, Bartoli M, Mollace V. Amyloid β peptide-induced inhibition of endothelial nitric oxide production involves oxidative stress-mediated constitutive eNOS/HSP90 interaction and disruption of agonist-mediated Akt activation. J Neuroinflammation 2015; 12:84. [PMID: 25935150 PMCID: PMC4438457 DOI: 10.1186/s12974-015-0304-x] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Accepted: 04/21/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Amyloid β (Aβ)-induced vascular dysfunction significantly contributes to the pathogenesis of Alzheimer's disease (AD). Aβ is known to impair endothelial nitric oxide synthase (eNOS) activity, thus inhibiting endothelial nitric oxide production (NO). METHOD In this study, we investigated Aβ-effects on heat shock protein 90 (HSP90) interaction with eNOS and Akt in cultured vascular endothelial cells and also explored the role of oxidative stress in this process. RESULTS Treatments of endothelial cells (EC) with Aβ promoted the constitutive association of HSP90 with eNOS but abrogated agonist (vascular endothelial growth factor (VEGF))-mediated HSP90 interaction with Akt. This effect resulted in blockade of agonist-mediated phosphorylation of Akt and eNOS at serine 1179. Furthermore, Aβ stimulated the production of reactive oxygen species in endothelial cells and concomitant treatments of the cells with the antioxidant N-acetyl-cysteine (NAC) prevented Aβ effects in promoting HSP90/eNOS interaction and rescued agonist-mediated Akt and eNOS phosphorylation. CONCLUSIONS The obtained data support the hypothesis that oxidative damage caused by Aβ results in altered interaction of HSP90 with Akt and eNOS, therefore promoting vascular dysfunction. This mechanism, by contributing to Aβ-mediated blockade of nitric oxide production, may significantly contribute to the cognitive impairment seen in AD patients.
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Affiliation(s)
- Folami Lamoke
- Department of Ophthalmology, Georgia Regents University, Health Sciences Campus, 1120 15th St., Augusta, GA, 30912, USA.
| | - Valeria Mazzone
- Department of Biology, University of Rome 'Roma Tre', Via Ostiense, 169, Rome, 00154, Italy.
| | - Tiziana Persichini
- Department of Biology, University of Rome 'Roma Tre', Via Ostiense, 169, Rome, 00154, Italy.
| | - Annamaria Maraschi
- Department of Neurology and Laboratory of Neuroscience, IRCCS Istituto Auxologico Italiano, Cusano Milanino 20095, Milan, Italy.
| | - Michael Brennan Harris
- Department of Kinesiology, College of William and Mary, 200 Stadium Dr., Williamsburg, VA, 23186, USA.
| | - Richard C Venema
- Vascular Biology Center, Georgia Regents University, 1120 15th St., Augusta, GA, 30912, USA.
| | - Marco Colasanti
- Department of Biology, University of Rome 'Roma Tre', Via Ostiense, 169, Rome, 00154, Italy.
| | - Micaela Gliozzi
- IRC-FSH, Department of Health Sciences, University of Catanzaro 'Magna Graecia', Catanzaro Complesso 'Ninì Barbieri', Roccelletta di Borgia, 88021, Italy.
| | - Carolina Muscoli
- IRC-FSH, Department of Health Sciences, University of Catanzaro 'Magna Graecia', Catanzaro Complesso 'Ninì Barbieri', Roccelletta di Borgia, 88021, Italy. .,IRCCS San Raffaele Pisana, Via di Val Cannuta, 247, 00166, Rome, Italy.
| | - Manuela Bartoli
- Department of Ophthalmology, Georgia Regents University, Health Sciences Campus, 1120 15th St., Augusta, GA, 30912, USA.
| | - Vincenzo Mollace
- IRC-FSH, Department of Health Sciences, University of Catanzaro 'Magna Graecia', Catanzaro Complesso 'Ninì Barbieri', Roccelletta di Borgia, 88021, Italy. .,IRCCS San Raffaele Pisana, Via di Val Cannuta, 247, 00166, Rome, Italy.
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Diabetes and Alzheimer disease, two overlapping pathologies with the same background: oxidative stress. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2015; 2015:985845. [PMID: 25815110 PMCID: PMC4357132 DOI: 10.1155/2015/985845] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 02/10/2015] [Indexed: 01/06/2023]
Abstract
There are several oxidative stress-related pathways interconnecting Alzheimer's disease and type II diabetes, two public health problems worldwide. Coincidences are so compelling that it is attractive to speculate they are the same disorder. However, some pathological mechanisms as observed in diabetes are not necessarily the same mechanisms related to Alzheimer's or the only ones related to Alzheimer's pathology. Oxidative stress is inherent to Alzheimer's and feeds a vicious cycle with other key pathological features, such as inflammation and Ca2+ dysregulation. Alzheimer's pathology by itself may lead to insulin resistance in brain, insulin resistance being an intervening variable in the neurodegenerative disorder. Hyperglycemia and insulin resistance from diabetes, overlapping with the Alzheimer's pathology, aggravate the progression of the neurodegenerative processes, indeed. But the same pathophysiological background is behind the consequences, oxidative stress. We emphasize oxidative stress and its detrimental role in some key regulatory enzymes.
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Contribution of reactive oxygen species to cerebral amyloid angiopathy, vasomotor dysfunction, and microhemorrhage in aged Tg2576 mice. Proc Natl Acad Sci U S A 2015; 112:E881-90. [PMID: 25675483 DOI: 10.1073/pnas.1414930112] [Citation(s) in RCA: 94] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Cerebral amyloid angiopathy (CAA) is characterized by deposition of amyloid β peptide (Aβ) within walls of cerebral arteries and is an important cause of intracerebral hemorrhage, ischemic stroke, and cognitive dysfunction in elderly patients with and without Alzheimer's Disease (AD). NADPH oxidase-derived oxidative stress plays a key role in soluble Aβ-induced vessel dysfunction, but the mechanisms by which insoluble Aβ in the form of CAA causes cerebrovascular (CV) dysfunction are not clear. Here, we demonstrate evidence that reactive oxygen species (ROS) and, in particular, NADPH oxidase-derived ROS are a key mediator of CAA-induced CV deficits. First, the NADPH oxidase inhibitor, apocynin, and the nonspecific ROS scavenger, tempol, are shown to reduce oxidative stress and improve CV reactivity in aged Tg2576 mice. Second, the observed improvement in CV function is attributed both to a reduction in CAA formation and a decrease in CAA-induced vasomotor impairment. Third, anti-ROS therapy attenuates CAA-related microhemorrhage. A potential mechanism by which ROS contribute to CAA pathogenesis is also identified because apocynin substantially reduces expression levels of ApoE-a factor known to promote CAA formation. In total, these data indicate that ROS are a key contributor to CAA formation, CAA-induced vessel dysfunction, and CAA-related microhemorrhage. Thus, ROS and, in particular, NADPH oxidase-derived ROS are a promising therapeutic target for patients with CAA and AD.
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Lin AJ, Liu G, Castello NA, Yeh JJ, Rahimian R, Lee G, Tsay V, Durkin AJ, Choi B, LaFerla FM, Chen Z, Green KN, Tromberg BJ. Optical imaging in an Alzheimer's mouse model reveals amyloid- β-dependent vascular impairment. NEUROPHOTONICS 2014; 1:011005. [PMID: 25133200 PMCID: PMC4132842 DOI: 10.1117/1.nph.1.1.011005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Alzheimer's disease (AD) and cerebrovascular disease are often comorbid conditions, but the relationship between amyloid-β and in vivo vascular pathophysiology is poorly understood. We utilized a multimodal, multiscale optical imaging approach, including spatial frequency domain imaging, Doppler optical coherence tomography, and confocal microscopy, to quantify AD-dependent changes in a triple transgenic mouse model (3xTg-AD) and age-matched controls. From three months of age (naïve) to 20 months (severe AD), the brain tissue concentration of total and oxy-hemoglobin (Total Hb, ctO2Hb) decreased 50 and 70%, respectively, in 3xTg-AD mice. Compared to age-matched controls, significant differences in brain hemoglobin concentrations occurred as early as eight months (Total Hb: 126 ± 5 μM versus 108 ± 4 μM; ctO2Hb: 86 ± 5 μM versus 70 ± 3 μM; for control and AD, respectively). These changes were linked to a 29% vascular volume fraction decrease and 35% vessel density reduction in the 20-month-old 3xTg-AD versus age-matched controls. Vascular reduction coincided with increased brain concentration of amyloid-β protein, vascular endothelial growth factor (VEGF), and endothelial nitric oxide synthase (eNOS) at eight and 20 months compared to the three-month baseline. Our results suggest that amyloid-β blocks the normally reparative effects of upregulated VEGF and eNOS, and may accelerate in vivo vascular pathophysiology in AD.
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Affiliation(s)
- Alexander J. Lin
- Beckman Laser Institute and Medical Clinic, Laser Microbeam and Medical Program, 1002 Health Sciences Road, Irvine, California 92612
- University of California Irvine, Department of Biomedical Engineering, 3120 Natural Sciences II, Irvine, California 92697-2715
| | - Gangjun Liu
- Beckman Laser Institute and Medical Clinic, Laser Microbeam and Medical Program, 1002 Health Sciences Road, Irvine, California 92612
| | - Nicholas A. Castello
- University of California Irvine, Institute for Memory Impairments and Neurological Disorders, 2642 Biological Sciences III Irvine, California 92697-4545
- University of California Irvine, Department of Neurobiology and Behavior, 2205 McGaugh Hall, Irvine, California 92697-4550
| | - James J. Yeh
- Beckman Laser Institute and Medical Clinic, Laser Microbeam and Medical Program, 1002 Health Sciences Road, Irvine, California 92612
| | - Rombod Rahimian
- Beckman Laser Institute and Medical Clinic, Laser Microbeam and Medical Program, 1002 Health Sciences Road, Irvine, California 92612
| | - Grace Lee
- Beckman Laser Institute and Medical Clinic, Laser Microbeam and Medical Program, 1002 Health Sciences Road, Irvine, California 92612
| | - Victoria Tsay
- Beckman Laser Institute and Medical Clinic, Laser Microbeam and Medical Program, 1002 Health Sciences Road, Irvine, California 92612
| | - Anthony J. Durkin
- Beckman Laser Institute and Medical Clinic, Laser Microbeam and Medical Program, 1002 Health Sciences Road, Irvine, California 92612
| | - Bernard Choi
- Beckman Laser Institute and Medical Clinic, Laser Microbeam and Medical Program, 1002 Health Sciences Road, Irvine, California 92612
- University of California Irvine, Department of Biomedical Engineering, 3120 Natural Sciences II, Irvine, California 92697-2715
| | - Frank M. LaFerla
- University of California Irvine, Institute for Memory Impairments and Neurological Disorders, 2642 Biological Sciences III Irvine, California 92697-4545
- University of California Irvine, Department of Neurobiology and Behavior, 2205 McGaugh Hall, Irvine, California 92697-4550
| | - Zhongping Chen
- Beckman Laser Institute and Medical Clinic, Laser Microbeam and Medical Program, 1002 Health Sciences Road, Irvine, California 92612
- University of California Irvine, Department of Biomedical Engineering, 3120 Natural Sciences II, Irvine, California 92697-2715
| | - Kim N. Green
- University of California Irvine, Institute for Memory Impairments and Neurological Disorders, 2642 Biological Sciences III Irvine, California 92697-4545
- University of California Irvine, Department of Neurobiology and Behavior, 2205 McGaugh Hall, Irvine, California 92697-4550
| | - Bruce J. Tromberg
- Beckman Laser Institute and Medical Clinic, Laser Microbeam and Medical Program, 1002 Health Sciences Road, Irvine, California 92612
- University of California Irvine, Department of Biomedical Engineering, 3120 Natural Sciences II, Irvine, California 92697-2715
- Address all correspondence to: Bruce J. Tromberg, E-mail:
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Cataldi M. The changing landscape of voltage-gated calcium channels in neurovascular disorders and in neurodegenerative diseases. Curr Neuropharmacol 2013; 11:276-97. [PMID: 24179464 PMCID: PMC3648780 DOI: 10.2174/1570159x11311030004] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Revised: 02/02/2013] [Accepted: 02/14/2013] [Indexed: 12/12/2022] Open
Abstract
It is a common belief that voltage-gated calcium channels (VGCC) cannot carry toxic amounts of Ca2+ in neurons. Also, some of them as L-type channels are essential for Ca2+-dependent regulation of prosurvival gene-programs. However, a wealth of data show a beneficial effect of drugs acting on VGCCs in several neurodegenerative and neurovascular diseases. In the present review, we explore several mechanisms by which the “harmless” VGCCs may become “toxic” for neurons. These mechanisms could explain how, though usually required for neuronal survival, VGCCs may take part in neurodegeneration. We will present evidence showing that VGCCs can carry toxic Ca2+ when: a) their density or activity increases because of aging, chronic hypoxia or exposure to β-amyloid peptides or b) Ca2+-dependent action potentials carry high Ca2+ loads in pacemaker neurons. Besides, we will examine conditions in which VGCCs promote neuronal cell death without carrying excess Ca2+. This can happen, for instance, when they carry metal ions into the neuronal cytoplasm or when a pathological decrease in their activity weakens Ca2+-dependent prosurvival gene programs. Finally, we will explore the role of VGCCs in the control of nonneuronal cells that take part to neurodegeneration like those of the neurovascular unit or of microglia.
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Affiliation(s)
- Mauro Cataldi
- Division of Pharmacology, Department of Neuroscience, Reproductive and Odontostomatological Sciences, Federico II University of Naples, Italy
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Fonseca ACRG, Ferreiro E, Oliveira CR, Cardoso SM, Pereira CF. Activation of the endoplasmic reticulum stress response by the amyloid-beta 1-40 peptide in brain endothelial cells. Biochim Biophys Acta Mol Basis Dis 2013; 1832:2191-203. [PMID: 23994613 DOI: 10.1016/j.bbadis.2013.08.007] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Revised: 07/28/2013] [Accepted: 08/20/2013] [Indexed: 01/09/2023]
Abstract
Neurovascular dysfunction arising from endothelial cell damage is an early pathogenic event that contributes to the neurodegenerative process occurring in Alzheimer's disease (AD). Since the mechanisms underlying endothelial dysfunction are not fully elucidated, this study was aimed to explore the hypothesis that brain endothelial cell death is induced upon the sustained activation of the endoplasmic reticulum (ER) stress response by amyloid-beta (Aβ) peptide, which deposits in the cerebral vessels in many AD patients and transgenic mice. Incubation of rat brain endothelial cells (RBE4 cell line) with Aβ1-40 increased the levels of several markers of ER stress-induced unfolded protein response (UPR), in a time-dependent manner, and affected the Ca(2+) homeostasis due to the release of Ca(2+) from this intracellular store. Finally, Aβ1-40 was shown to activate both mitochondria-dependent and -independent apoptotic cell death pathways. Enhanced release of cytochrome c from mitochondria and activation of the downstream caspase-9 were observed in cells treated with Aβ1-40 concomitantly with caspase-12 activation. Furthermore, Aβ1-40 activated the apoptosis effectors' caspase-3 and promoted the translocation of apoptosis-inducing factor (AIF) to the nucleus demonstrating the involvement of caspase-dependent and -independent mechanisms during Aβ-induced endothelial cell death. In conclusion, our data demonstrate that ER stress plays a significant role in Aβ1-40-induced apoptotic cell death in brain endothelial cells suggesting that ER stress-targeted therapeutic strategies might be useful in AD to counteract vascular defects and ultimately neurodegeneration.
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Affiliation(s)
- Ana Catarina R G Fonseca
- Center for Neuroscience and Cell Biology, University of Coimbra, Largo Marquês de Pombal, 3004-517 Coimbra, Portugal; Department of Life Sciences, Faculty of Sciences and Technology, University of Coimbra, Apartado 3046, 3001-401 Coimbra, Portugal
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Carrizzo A, Puca A, Damato A, Marino M, Franco E, Pompeo F, Traficante A, Civitillo F, Santini L, Trimarco V, Vecchione C. Resveratrol improves vascular function in patients with hypertension and dyslipidemia by modulating NO metabolism. Hypertension 2013; 62:359-66. [PMID: 23753407 DOI: 10.1161/hypertensionaha.111.01009] [Citation(s) in RCA: 111] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Epidemiological studies have demonstrated that the Mediterranean diet, which is rich in resveratrol, is associated with a significantly reduced risk of cardiovascular disease. However, the molecular mechanisms that underlie the beneficial effects of resveratrol on cardiovascular function remain incompletely understood. Therefore, we set out to identify the molecular target(s) mediating the protective action of resveratrol on vascular function. To this end, we performed vascular reactivity studies to evaluate the effects of resveratrol on superior thyroid artery obtained from 59 patients with hypertension and dyslipidemia. We found that resveratrol evoked vasorelaxation and reduced endothelial dysfunction through the modulation of NO metabolism via (1) an 5' adenosine monophosphate-activated protein kinase-mediated increase in endothelial NO synthase activity; (2) a rise in tetrahydrobiopterin levels, which also increases endothelial NO synthase activity; and (3) attenuation of vascular oxidative stress, brought about by overexpression of manganese superoxide dismutase via an nuclear factor erythroid-derived 2-like 2-dependent mechanism. The effects of resveratrol on acetylcholine vasorelaxation were also tested in vessels from patients with nonhypertensive nondyslipidemia undergoing thyroid surgery. In this setting, resveratrol failed to exert any effect. Thus, our finding that resveratrol reduces endothelial dysfunction, an early pathophysiological feature and independent predictor of poor prognosis in most forms of cardiovascular disease, supports the concept that the risk of vascular events could be further reduced by adherence to a set of dietary and behavioral guidelines.
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Affiliation(s)
- Albino Carrizzo
- Vascular Physiopathology Unit, University of Naples Federico II, Naples, Italy
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Salvolini E, Vignini A, Nanetti L, Luzzi S, Provinciali L, Di Primio R, Mazzanti L. Effects of Plasma from Patients Affected by Mild Cognitive Impairment and Alzheimer's Disease on Cultured Endothelial Cells. EUR J INFLAMM 2013; 11:469-477. [DOI: 10.1177/1721727x1301100216] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/01/2024] Open
Abstract
There is accumulating evidence that Alzheimer's disease (AD) can have vascular contribution. In particular, endothelial dysfunction may impair nitric oxide (NO) production and cause cerebral hypoperfusion. Blood flow impairment can be provoked also by an increased production of reactive oxygen species (ROS). The present study was performed in order to investigate the effect of plasma from subjects affected by AD and mild cognitive impairment (MCI) on human aortic endothelial cells (HAECs) in vitro, since endothelial dysfunction has been suggested to be an early event in patients affected by AD. Plasma samples were obtained from 27 AD patients, 15 MCI subjects, and 19 age-and sex-matched healthy subjects. After a short incubation period the following parameters were evaluated: NO release, superoxide dismutase (SOD) and Na+/K+-ATPase activities, membrane fluidity, and thiobarbituric acid-reactive substance (TBARS) production. Exposure to MCI plasma provoked a decrease in NO release, more pronounced in the presence of AD plasma. Our data on SOD and Na+/K+-ATPase activities showed a similar trend, since the lowest values were recorded after incubation with AD plasma. Endothelial membrane fluidity was deeply affected by the exposure to MCI plasma, and even more following incubation with AD plasma. Finally, enhanced TBARS production after incubation with MCI and AD plasma was observed. In conclusion, our results showed that MCI and AD plasma affects endothelial cells, thus highlighting the need for early treatment aimed at protecting the endothelium.
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Affiliation(s)
- E. Salvolini
- Dipartimento di Scienze Cliniche e Molecolari - Istologia, Università Politecnica delle Marche, Ancona, Italy
| | - A. Vignini
- Dipartimento di Scienze Cliniche Specialistiche ed Odontostomatologiche - Biochimica, Università Politecnica delle Marche, Ancona, Italy
| | - L. Nanetti
- Dipartimento di Scienze Cliniche Specialistiche ed Odontostomatologiche - Biochimica, Università Politecnica delle Marche, Ancona, Italy
| | - S. Luzzi
- Dipartimento di Medicina Sperimentale e Clinica, Clinica Neurologica, Università Politecnica delle Marche, Ancona, Italy
| | - L. Provinciali
- Dipartimento di Medicina Sperimentale e Clinica, Clinica Neurologica, Università Politecnica delle Marche, Ancona, Italy
| | - R. Di Primio
- Dipartimento di Scienze Cliniche e Molecolari - Istologia, Università Politecnica delle Marche, Ancona, Italy
| | - L. Mazzanti
- Dipartimento di Scienze Cliniche Specialistiche ed Odontostomatologiche - Biochimica, Università Politecnica delle Marche, Ancona, Italy
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Bölükbaşı Hatip FF, Hatip-Al-Khatib I. Effects of β-sheet breaker peptides on altered responses of thoracic aorta in rats' Alzheimer's disease model induced by intraamygdaloid Aβ40. Life Sci 2013; 92:228-36. [DOI: 10.1016/j.lfs.2012.12.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Revised: 11/15/2012] [Accepted: 12/13/2012] [Indexed: 02/04/2023]
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Nguyen H, Chiasson VL, Chatterjee P, Kopriva SE, Young KJ, Mitchell BM. Interleukin-17 causes Rho-kinase-mediated endothelial dysfunction and hypertension. Cardiovasc Res 2012; 97:696-704. [PMID: 23263331 DOI: 10.1093/cvr/cvs422] [Citation(s) in RCA: 194] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
AIMS Elevated levels of pro-inflammatory cytokine interleukin-17A (IL-17) are associated with hypertensive autoimmune diseases; however, the connection between IL-17 and hypertension is unknown. We hypothesized that IL-17 increases blood pressure by decreasing endothelial nitric oxide production. METHODS AND RESULTS Acute treatment of endothelial cells with IL-17 caused a significant increase in phosphorylation of the inhibitory endothelial nitric oxide (NO) synthase residue threonine 495 (eNOS Thr495). Of the kinases known to phosphorylate eNOS Thr495, only inhibition of Rho-kinase prevented the IL-17-induced increase. IL-17 caused a threefold increase in the Rho-kinase activator RhoA, and this was prevented by an IL-17 neutralizing antibody. In isolated mouse aortas, IL-17 significantly increased eNOS Thr495 phosphorylation, induced RhoA expression, and decreased NO-dependent relaxation responses, all of which were prevented by either an IL-17 neutralizing antibody or inhibition of Rho-kinase. In mice, IL-17 treatment for 1 week significantly increased systolic blood pressure and this was associated with decreased aortic NO-dependent relaxation responses, increased eNOS Thr495 phosphorylation, and increased RhoA expression. Inhibition of Rho-kinase prevented the hypertension caused by IL-17. CONCLUSION These data demonstrate that IL-17 activates RhoA/Rho-kinase leading to endothelial dysfunction and hypertension. Inhibitors of IL-17 or Rho-kinase may prove useful as anti-hypertensive drugs in IL-17-associated autoimmune diseases.
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Affiliation(s)
- Hoanglan Nguyen
- Division of Nephrology & Hypertension, Department of Internal Medicine, Texas A&M Health Science Center College of Medicine/Scott & White Memorial Hospital, 702 SW HK Dodgen Loop, Temple, TX 76504, USA
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Villaflores OB, Chen YJ, Chen CP, Yeh JM, Wu TY. Curcuminoids and resveratrol as anti-Alzheimer agents. Taiwan J Obstet Gynecol 2012; 51:515-25. [DOI: 10.1016/j.tjog.2012.09.005] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/20/2012] [Indexed: 12/24/2022] Open
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Pimentel-Coelho PM, Rivest S. The early contribution of cerebrovascular factors to the pathogenesis of Alzheimer’s disease. Eur J Neurosci 2012; 35:1917-37. [DOI: 10.1111/j.1460-9568.2012.08126.x] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Role of Cytosolic Calcium-Dependent Phospholipase A2 in Alzheimer's Disease Pathogenesis. Mol Neurobiol 2012; 45:596-604. [DOI: 10.1007/s12035-012-8279-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Accepted: 05/08/2012] [Indexed: 12/13/2022]
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Krzyzanowska A, Carro E. Pathological alteration in the choroid plexus of Alzheimer's disease: implication for new therapy approaches. Front Pharmacol 2012; 3:75. [PMID: 22563316 PMCID: PMC3342675 DOI: 10.3389/fphar.2012.00075] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Accepted: 04/10/2012] [Indexed: 01/28/2023] Open
Abstract
Morphological alterations of choroid plexus in Alzheimer’s disease (AD) have been extensively investigated. These changes include epithelial atrophy, thickening of the basement membrane, and stroma fibrosis. As a result, synthesis, secretory, and transportation functions are significantly altered resulting in decreased cerebrospinal fluid (CSF) turnover. Recent studies discuss the potential impacts of these changes, including the possibility of reduced resistance to stress insults and slow clearance of toxic compounds from CSF with specific reference to the amyloid peptide. Here, we review new evidences for AD-related changes in the choroid plexus. The data suggest that the significantly altered functions of the choroid plexus contribute to the multiparametric pathogenesis of late-onset AD.
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Affiliation(s)
- Agnieszka Krzyzanowska
- Neuroscience Group, Instituto de Investigacion Hospital 12 de Octubre (i+12) Madrid, Spain
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Misiti F, Carelli-Alinovi C, Sampaolese B, Giardina B. β-amyloid decreases detectable endothelial nitric oxide synthase in human erythrocytes: a role for membrane acetylcholinesterase. Cell Biochem Funct 2012; 30:474-9. [PMID: 22431227 DOI: 10.1002/cbf.2822] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2011] [Revised: 02/17/2012] [Accepted: 02/28/2012] [Indexed: 01/08/2023]
Abstract
Until few years ago, many studies of Alzheimer's disease investigated the effects of this syndrome in the central nervous system. Only recently, the detection of amyloid beta peptide (Aβ) in the blood has evidenced the necessity to extend studies on extraneuronal cells, particularly on erythrocytes. Aβ is also present in brain capillaries, where it interacts with the erythrocytes, inducing several metabolic and functional alterations. Recently, functionally active endothelial type nitric oxide synthase (eNOS) was discovered in human erythrocytes. The goal of the present study was to evidence the effect of Aβ on erythrocyte eNOS. We found that Aβ following to 24-h exposure causes a decrease in the immune staining of erythrocyte eNOS. Concurrently, Aβ alters erythrocyte cell morphology, decreases nitrites and nitrates levels, and affects membrane acetylcholinesterase activity. Propidium, an acetylcholinesterase inhibitor, was able to reverse the effects elicited by Aβ. These events could contribute to the vascular alterations associated with Alzheimer's disease disease.
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Affiliation(s)
- Francesco Misiti
- Department of Human Sciences, Society and Health, University of Cassino and Southern Lazio, Cassino, Italy.
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40
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Age-related changes in endothelial function and blood flow regulation. Pharmacol Ther 2012; 133:159-76. [DOI: 10.1016/j.pharmthera.2011.10.004] [Citation(s) in RCA: 130] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2011] [Accepted: 10/14/2011] [Indexed: 01/12/2023]
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Lee ST, Chu K, Park JE, Jung KH, Jeon D, Lim JY, Lee SK, Kim M, Roh JK. Erythropoietin improves memory function with reducing endothelial dysfunction and amyloid-beta burden in Alzheimer's disease models. J Neurochem 2011; 120:115-24. [PMID: 22004348 DOI: 10.1111/j.1471-4159.2011.07534.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Neurovascular degeneration contributes to the pathogenesis of Alzheimer's disease (AD). Because erythropoietin (EPO) promotes endothelial regeneration, we investigated the therapeutic effects of EPO in animal models of AD. In aged Tg2576 mice, EPO receptors (EPORs) were expressed in the cortex and hippocampus. Tg2576 mice were treated with daily injection of EPO (5000 IU/kg/day) for 5 days. At 14 days, EPO improved contextual memory as measured by fear-conditioning test. EPO enhanced endothelial proliferation and the level of synaptophysin expression in the brain. EPO also increased capillary density, and decreased the level of the receptor for advanced glycation endproducts (RAGE) in the brain, while decreasing in the amount of amyloid plaque and amyloid-β (Aβ). In cultured human endothelial cells, EPO enhanced angiogenesis and suppressed the expression of the RAGE. These results show that EPO improves memory and ameliorates endothelial degeneration induced by Aβ in AD models. This pre-clinical evidence suggests that EPO may be useful for the treatment of AD.
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Affiliation(s)
- Soon-Tae Lee
- Department of Neurology, Seoul National University Hospital, Seoul, South Korea
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42
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Chiasson VL, Quinn MA, Young KJ, Mitchell BM. Protein kinase CbetaII-mediated phosphorylation of endothelial nitric oxide synthase threonine 495 mediates the endothelial dysfunction induced by FK506 (tacrolimus). J Pharmacol Exp Ther 2011; 337:718-23. [PMID: 21383022 DOI: 10.1124/jpet.110.178095] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
FK506 [tacrolimus; hexadecahydro-5,19-dihydroxy-3-[2-(4-hydroxy-3-methoxycyclohexyl)-1-methylethenyl]-14,16-dimethoxy-4,10,12,18-tetramethyl-8-(2-propenyl)-15,19-epoxy-3H-pyrido[2,1-c][1,4]oxa-azacyclotricosine-1,7,20,21(4H,23H)-tetrone] is used clinically to reduce the incidence of allograft rejection; however, chronic administration leads to endothelial dysfunction and hypertension. We have previously shown that FK506 activates Ca(2+)/diacylglycerol-dependent conventional protein kinase C (cPKC), which phosphorylates endothelial nitric oxide synthase (eNOS) at one of its inhibitory sites, Thr495. However, which cPKC isoform is responsible for phosphorylating eNOS Thr495 is unknown. The aim of the current study was to determine the cPKC isoform that is activated by FK506, leading to decreased endothelial function. FK506 reduced endothelium-dependent relaxation responses, yet had no effect on endothelium-independent relaxation responses in aortas from control mice. Of the various cPKC isoforms, only the administration of a PKCβ(II) isoform-specific peptide inhibitor restored aortic relaxation responses to that of controls. In aortic endothelial cells, FK506 significantly increased PKCβ(II) activation compared with vehicle-treated controls, and this was prevented by a PKCβ(II) isoform-specific peptide inhibitor. In addition, a PKCβ(II) isoform-specific peptide inhibitor prevented the increase in eNOS Thr495 phosphorylation induced by FK506. Taken together, our results indicate that β(II) is the cPKC isoform responsible for phosphorylating eNOS at the inhibitory site Thr495 in response to FK506. PKCβ(II) inhibition could prove beneficial in ameliorating the endothelial dysfunction and hypertension in patients treated with FK506.
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Affiliation(s)
- Valorie L Chiasson
- Department of Internal Medicine, Division of Nephrology and Hypertension, Texas A&M Health Science Center, Temple, TX 76504, USA
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43
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Palmer J, Love S. Endothelin receptor antagonists: potential in Alzheimer's disease. Pharmacol Res 2010; 63:525-31. [PMID: 21193044 DOI: 10.1016/j.phrs.2010.12.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2010] [Revised: 12/17/2010] [Accepted: 12/17/2010] [Indexed: 12/20/2022]
Abstract
Alzheimer's disease (AD) is believed to be initiated by the accumulation of neurotoxic forms of Aβ peptide within the brain. AD patients show reduction of cerebral blood flow (CBF), the extent of the reduction correlating with the impairment of cognition. There is evidence that cerebral hypoperfusion precedes and may even trigger the onset of dementia in AD. Cerebral hypoperfusion impairs neuronal function, reduces the clearance of Aβ peptide and other toxic metabolites from the brain, and upregulates Aβ production. Studies in animal models of AD have shown the reduction in CBF to be more than would be expected for the reduction in neuronal metabolic activity. Aβ may contribute to the reduction in CBF in AD, as both Aβ₁₋₄₀ and Aβ₁₋₄₂ induce cerebrovascular dysfunction. Aβ₁₋₄₀ acts directly on cerebral arteries to cause cerebral smooth muscle cell contraction. Aβ₁₋₄₂ causes increased neuronal production and release of endothelin-1 (ET-1), a potent vasoconstrictor, and upregulation of endothelin-converting enzyme-2 (ECE-2), the enzyme which cleaves ET-1 from its inactive precursor. ET-1 and ECE-2 are also elevated in AD, making it likely that upregulation of the ECE-2-ET-1 axis by Aβ₁₋₄₂ contributes to the chronic reduction of CBF in AD. At present, only a few symptomatic treatment options exist for AD. The involvement of ET-1 in the pathogenesis of endothelial dysfunction associated with elevated Aβ indicates the potential for endothelin receptor antagonists in the treatment of AD. It has already been demonstrated that the endothelin receptor antagonist bosentan, preserves aortic and carotid endothelial function in Tg2576 mice, and our findings suggest that endothelin receptor antagonists may be beneficial in maintaining CBF in AD.
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Affiliation(s)
- Jennifer Palmer
- Dementia Research Group, Institute of Clinical Neurosciences, School of Clinical Sciences, University of Bristol, Frenchay Hospital, Bristol BS16 1LE, United Kingdom.
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Bauer EM, Qin Y, Miller TW, Bandle RW, Csanyi G, Pagano PJ, Bauer PM, Schnermann J, Roberts DD, Isenberg JS. Thrombospondin-1 supports blood pressure by limiting eNOS activation and endothelial-dependent vasorelaxation. Cardiovasc Res 2010; 88:471-81. [PMID: 20610415 DOI: 10.1093/cvr/cvq218] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
AIMS Thrombospondin-1 (TSP1), via its necessary receptor CD47, inhibits nitric oxide (NO)-stimulated soluble guanylate cyclase activation in vascular smooth muscle cells, and TSP1-null mice have increased shear-dependent blood flow compared with wild-type mice. Yet, the endothelial basement membrane should in theory function as a barrier to diffusion of soluble TSP1 into the arterial smooth muscle cell layer. These findings suggested that endothelial-dependent differences in blood flow in TSP1-null mice may be the result of direct modulation of endothelial NO synthase (eNOS) activation by circulating TSP1. Here we tested the hypothesis that TSP1 inhibits eNOS activation and endothelial-dependent arterial relaxation. METHODS AND RESULTS Acetylcholine (ACh)-stimulated activation of eNOS and agonist-driven calcium transients in endothelial cells were inhibited by TSP1. TSP1 also inhibited eNOS phosphorylation at serine(1177). TSP1 treatment of the endothelium of wild-type and TSP1-null but not CD47-null arteries inhibited ACh-stimulated relaxation. TSP1-null vessels demonstrated greater endothelial-dependent vasorelaxation compared with the wild type. Conversely, TSP1-null arteries demonstrated less vasoconstriction to phenylephrine compared with the wild type, which was corrected upon inhibition of eNOS. In TSP1-null mice, intravenous TSP1 blocked ACh-stimulated decreases in blood pressure, and both intravenous TSP1 and a CD47 agonist antibody acutely elevated blood pressure in mice. CONCLUSION TSP1, via CD47, inhibits eNOS activation and endothelial-dependent arterial relaxation and limits ACh-driven decreases in blood pressure. Conversely, intravenous TSP1 and a CD47 antibody increase blood pressure. These findings suggest that circulating TSP1, by limiting endogenous NO production, functions as a pressor agent supporting blood pressure.
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Affiliation(s)
- Eileen M Bauer
- Vascular Medicine Institute of University of Pittsburgh, Pittsburgh, PA, USA
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Soluble amyloid-beta, effect on cerebral arteriolar regulation and vascular cells. Mol Neurodegener 2010; 5:15. [PMID: 20388225 PMCID: PMC2873254 DOI: 10.1186/1750-1326-5-15] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2010] [Accepted: 04/13/2010] [Indexed: 12/22/2022] Open
Abstract
Background Evidence indicates that soluble forms of amyloid-β (Aβ) are vasoactive, which may contribute to cerebrovascular dysfunction noted in patients with Alzheimer's Disease and cerebral amyloid angiopathy. The effects of soluble Aβ on penetrating cerebral arterioles - the vessels most responsible for controlling cerebrovascular resistance - have not been studied. Results Freshly dissolved Aβ1-40 and Aβ1-42, but not the reverse peptide Aβ40-1 constricted isolated rat penetrating arterioles and diminished dilation to adenosine tri-phosphate (ATP). Aβ1-42 also enhanced ATP-induced vessel constriction. Aβ1-40 diminished arteriolar myogenic response, and an anti-Aβ antibody reduced Aβ1-40 induced arteriolar constriction. Prolonged Aβ exposure in vessels of Tg2576 mice resulted in a marked age-dependent effect on ATP-induced vascular responses. Vessels from 6 month old Tg2576 mice had reduced vascular responses whereas these were absent from 12 month old animals. Aβ1-40 and Aβ1-42 acutely increased production of reactive oxygen species (ROS) in cultured rat cerebro-microvascular cells. The radical scavenger MnTBAP attenuated this Aβ-induced oxidative stress and Aβ1-40-induced constriction in rat arterioles. Conclusions Our results suggest that soluble Aβ1-40 and Aβ1-42 directly affect the vasomotor regulation of isolated rodent penetrating arterioles, and that ROS partially mediate these effects. Once insoluble Aβ deposits are present, arteriolar reactivity is greatly diminished.
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Palmer JC, Kehoe PG, Love S. Endothelin-converting enzyme-1 in Alzheimer's disease and vascular dementia. Neuropathol Appl Neurobiol 2010; 36:487-97. [DOI: 10.1111/j.1365-2990.2010.01084.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Sadowski MJ. Circulating angiogenic cells and Alzheimer's disease: contribution of the bone marrow to the pathogenesis of the disease. J Alzheimers Dis 2010; 19:1241-3. [PMID: 20308790 PMCID: PMC3713606 DOI: 10.3233/jad-2010-01343] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Martin J Sadowski
- Department of Neurology, New York University School of Medicine, New York, NY 10016, USA.
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Phosphodiesterase 5 inhibition improves synaptic function, memory, and amyloid-beta load in an Alzheimer's disease mouse model. J Neurosci 2009; 29:8075-86. [PMID: 19553447 DOI: 10.1523/jneurosci.0864-09.2009] [Citation(s) in RCA: 224] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Memory loss, synaptic dysfunction, and accumulation of amyloid beta-peptides (A beta) are major hallmarks of Alzheimer's disease (AD). Downregulation of the nitric oxide/cGMP/cGMP-dependent protein kinase/c-AMP responsive element-binding protein (CREB) cascade has been linked to the synaptic deficits after A beta elevation. Here, we report that the phosphodiesterase 5 inhibitor (PDE5) sildenafil (Viagra), a molecule that enhances phosphorylation of CREB, a molecule involved in memory, through elevation of cGMP levels, is beneficial against the AD phenotype in a mouse model of amyloid deposition. We demonstrate that the inhibitor produces an immediate and long-lasting amelioration of synaptic function, CREB phosphorylation, and memory. This effect is also associated with a long-lasting reduction of A beta levels. Given that side effects of PDE5 inhibitors are widely known and do not preclude their administration to a senile population, these drugs have potential for the treatment of AD and other diseases associated with elevated A beta levels.
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Ali AK, Banks WA, Kumar VB, Shah GN, Lynch JL, Farr SA, Fleegal-DeMotta MA, Morley JE. Nitric oxide activity and isoenzyme expression in the senescence-accelerated mouse p8 model of Alzheimer's disease: effects of anti-amyloid antibody and antisense treatments. J Gerontol A Biol Sci Med Sci 2009; 64:1025-30. [PMID: 19531769 DOI: 10.1093/gerona/glp074] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Amyloid beta protein (Abeta) in Alzheimer's disease induces oxidative stress through several mechanisms, including stimulation of nitric oxide synthase (NOS) activity. We examined NOS activity and expression in the senescence-accelerated mouse P8 (SAMP8) line. The SAMP8 strain develops with aging cognitive impairments, increases in Abeta, and oxidative stress, all reversed by amyloid precursor protein antisense or Abeta antibody treatment. We found here that hippocampal NOS activity in 12-month-old SAMP8 mice was nearly double that of 2-month-old SAMP8 or CD-1 mice, but with no change in NOS isoenzyme mRNA and protein levels. Antisense or antibody treatment further increased NOS activity in aged SAMP8 mice. Antisense treatment increased inducible NOS (iNOS) mRNA levels, decreased neuronal NOS mRNA and protein levels, but did not affect endothelial NOS (eNOS) or iNOS protein or eNOS mRNA levels. These results suggest a complex relation between Abeta and NOS in the SAMP8 that is largely mediated through posttranslational mechanisms.
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Affiliation(s)
- Abbas K Ali
- Geriatric Research Education and Clinical Center, Veterans Affairs Medical Center-St Louis, MO 63106, USA
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Role of Nitric Oxide in Prevention of Cognitive Disorders in Neurodegenerative Brain Injuries in Rats. Bull Exp Biol Med 2009; 146:391-5. [DOI: 10.1007/s10517-009-0315-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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