1
|
Stepanichev MY, Mamedova DI, Gulyaeva NV. Hippocampus under Pressure: Molecular Mechanisms of Development of Cognitive Impairments in SHR Rats. BIOCHEMISTRY. BIOKHIMIIA 2024; 89:711-725. [PMID: 38831507 DOI: 10.1134/s0006297924040102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 11/20/2023] [Accepted: 03/14/2024] [Indexed: 06/05/2024]
Abstract
Data from clinical trials and animal experiments demonstrate relationship between chronic hypertension and development of cognitive impairments. Here, we review structural and biochemical alterations in the hippocampus of SHR rats with genetic hypertension, which are used as a model of essential hypertension and vascular dementia. In addition to hypertension, dysfunction of the hypothalamic-pituitary-adrenal system observed in SHR rats already at an early age may be a key factor of changes in the hippocampus at the structural and molecular levels. Global changes at the body level, such as hypertension and neurohumoral dysfunction, are associated with the development of vascular pathology and impairment of the blood-brain barrier. Changes in multiple biochemical glucocorticoid-dependent processes in the hippocampus, including dysfunction of steroid hormones receptors, impairments of neurotransmitter systems, BDNF deficiency, oxidative stress, and neuroinflammation are accompanied by the structural alterations, such as cellular signs of neuroinflammation micro- and astrogliosis, impairments of neurogenesis in the subgranular neurogenic zone, and neurodegenerative processes at the level of synapses, axons, and dendrites up to the death of neurons. The consequence of this is dysfunction of hippocampus, a key structure of the limbic system necessary for cognitive functions. Taking into account the available results at various levels starting from the body and brain structure (hippocampus) levels to molecular one, we can confirm translational validity of SHR rats for modeling mechanisms of vascular dementia.
Collapse
Affiliation(s)
- Mikhail Yu Stepanichev
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, 117485, Russia.
| | - Diana I Mamedova
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, 117485, Russia
| | - Natalia V Gulyaeva
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, 117485, Russia
| |
Collapse
|
2
|
Berisha DE, Rizvi B, Chappel-Farley MG, Tustison N, Taylor L, Dave A, Sattari NS, Chen IY, Lui KK, Janecek JC, Keator D, Neikrug AB, Benca RM, Yassa MA, Mander BA. Cerebrovascular pathology mediates associations between hypoxemia during rapid eye movement sleep and medial temporal lobe structure and function in older adults. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.28.577469. [PMID: 38328085 PMCID: PMC10849660 DOI: 10.1101/2024.01.28.577469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Obstructive sleep apnea (OSA) is common in older adults and is associated with medial temporal lobe (MTL) degeneration and memory decline in aging and Alzheimer's disease (AD). However, the underlying mechanisms linking OSA to MTL degeneration and impaired memory remains unclear. By combining magnetic resonance imaging (MRI) assessments of cerebrovascular pathology and MTL structure with clinical polysomnography and assessment of overnight emotional memory retention in older adults at risk for AD, cerebrovascular pathology in fronto-parietal brain regions was shown to statistically mediate the relationship between OSA-related hypoxemia, particularly during rapid eye movement (REM) sleep, and entorhinal cortical thickness. Reduced entorhinal cortical thickness was, in turn, associated with impaired overnight retention in mnemonic discrimination ability across emotional valences for high similarity lures. These findings identify cerebrovascular pathology as a contributing mechanism linking hypoxemia to MTL degeneration and impaired sleep-dependent memory in older adults.
Collapse
Affiliation(s)
- Destiny E. Berisha
- Department of Neurobiology and Behavior, University of California Irvine, Irvine CA, 92697, USA
- Center for the Neurobiology of Learning and Memory, University of California Irvine, Irvine CA, 92697, USA
| | - Batool Rizvi
- Department of Neurobiology and Behavior, University of California Irvine, Irvine CA, 92697, USA
- Center for the Neurobiology of Learning and Memory, University of California Irvine, Irvine CA, 92697, USA
| | - Miranda G. Chappel-Farley
- Department of Neurobiology and Behavior, University of California Irvine, Irvine CA, 92697, USA
- Center for the Neurobiology of Learning and Memory, University of California Irvine, Irvine CA, 92697, USA
| | - Nicholas Tustison
- Center for the Neurobiology of Learning and Memory, University of California Irvine, Irvine CA, 92697, USA
| | - Lisa Taylor
- Department of Neurobiology and Behavior, University of California Irvine, Irvine CA, 92697, USA
- Center for the Neurobiology of Learning and Memory, University of California Irvine, Irvine CA, 92697, USA
- Department of Psychiatry and Human Behavior, University of California Irvine, Irvine CA, 92697, USA
| | - Abhishek Dave
- Department of Cognitive Sciences, University of California Irvine, Irvine CA, 92697, USA
| | - Negin S. Sattari
- Department of Psychiatry and Human Behavior, University of California Irvine, Irvine CA, 92697, USA
| | - Ivy Y. Chen
- Department of Psychiatry and Human Behavior, University of California Irvine, Irvine CA, 92697, USA
| | - Kitty K. Lui
- San Diego State University/University of California San Diego, Joint Doctoral Program in Clinical Psychology, San Diego, CA, 92093, USA
| | - John C. Janecek
- Department of Neurobiology and Behavior, University of California Irvine, Irvine CA, 92697, USA
- Center for the Neurobiology of Learning and Memory, University of California Irvine, Irvine CA, 92697, USA
| | - David Keator
- Department of Psychiatry and Human Behavior, University of California Irvine, Irvine CA, 92697, USA
| | - Ariel B. Neikrug
- Department of Psychiatry and Human Behavior, University of California Irvine, Irvine CA, 92697, USA
| | - Ruth M. Benca
- Department of Neurobiology and Behavior, University of California Irvine, Irvine CA, 92697, USA
- Center for the Neurobiology of Learning and Memory, University of California Irvine, Irvine CA, 92697, USA
- Department of Psychiatry and Human Behavior, University of California Irvine, Irvine CA, 92697, USA
- Neuroscience Training Program, University of Wisconsin-Madison, Madison, WI, 53706, USA
- Department of Psychiatry, University of Wisconsin-Madison, Madison, 53706, WI, USA
- Department of Psychiatry and Behavioral Medicine, Wake Forest University, Winston-Salem, NC, 27109, USA
- Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine CA, 92697, USA
| | - Michael A. Yassa
- Department of Neurobiology and Behavior, University of California Irvine, Irvine CA, 92697, USA
- Center for the Neurobiology of Learning and Memory, University of California Irvine, Irvine CA, 92697, USA
- Department of Psychiatry and Human Behavior, University of California Irvine, Irvine CA, 92697, USA
- Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine CA, 92697, USA
- Department of Neurology, University of California Irvine, Irvine CA, 92697, USA
| | - Bryce A. Mander
- Center for the Neurobiology of Learning and Memory, University of California Irvine, Irvine CA, 92697, USA
- Department of Psychiatry and Human Behavior, University of California Irvine, Irvine CA, 92697, USA
- Department of Cognitive Sciences, University of California Irvine, Irvine CA, 92697, USA
- Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine CA, 92697, USA
- Department of Pathology and Laboratory Medicine, University of California Irvine, Irvine CA, 92697, USA
| |
Collapse
|
3
|
Li Y, Chu X, Xie X, Guo J, Meng J, Si Q, Jiang P. Integrating transcriptomics and metabolomics to analyze the mechanism of hypertension-induced hippocampal injury. Front Mol Neurosci 2023; 16:1146525. [PMID: 37089694 PMCID: PMC10115962 DOI: 10.3389/fnmol.2023.1146525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 03/13/2023] [Indexed: 04/08/2023] Open
Abstract
ObjectiveHypertension is a public health challenge worldwide due to its high prevalence and multiple complications. Hypertension-induced damage to the hippocampus leads to behavioral changes and various brain diseases. Despite the multifaceted effects of hypertension on the hippocampus, the mechanisms underlying hippocampal lesions are still unclear.MethodsThe 32-week-old spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats were selected as the study subjects. Behavioral experiments such as an open field test (OFT), an elevated plus maze (EPM) test, and the Morris water maze (MWM) test were performed to show the behavioral characteristics of the rats. A comprehensive transcriptomic and metabolomic analysis was performed to understand the changes in the hippocampus at the metabolic and genetic levels.ResultsBehavioral tests showed that, compared to WKY rats, SHR showed not only reduced memory capacity but more hyperactive and impulsive behavior. In addition, transcriptomic analysis screened for 103 differentially expressed genes. Metabolomic analysis screened 56 metabolites with significant differences, including various amino acids and their related metabolites.ConclusionComprehensive analysis showed that hypertension-induced hippocampal lesions are closely associated with differential metabolites and differential genes detected in this study. The results provide a basis for analyzing the mechanisms of hypertension-induced hippocampal damage.
Collapse
Affiliation(s)
- Yanan Li
- Translational Pharmaceutical Laboratory, Jining First People’s Hospital, Shandong First Medical University, Jining, China
| | - Xue Chu
- Translational Pharmaceutical Laboratory, Jining First People’s Hospital, Shandong First Medical University, Jining, China
| | - Xin Xie
- Translational Pharmaceutical Laboratory, Jining First People’s Hospital, Shandong First Medical University, Jining, China
- School of Pharmaceutical Sciences, Gannan Medical University, Ganzhou, China
| | - Jinxiu Guo
- Translational Pharmaceutical Laboratory, Jining First People’s Hospital, Shandong First Medical University, Jining, China
| | - Junjun Meng
- Translational Pharmaceutical Laboratory, Jining First People’s Hospital, Shandong First Medical University, Jining, China
| | - Qingying Si
- Department of Endocrinology, Tengzhou Central People's Hospital, Tengzhou, China
| | - Pei Jiang
- Translational Pharmaceutical Laboratory, Jining First People’s Hospital, Shandong First Medical University, Jining, China
- Institute of Translational Pharmacy, Jining Medical Research Academy, Jining, China
- *Correspondence: Pei Jiang,
| |
Collapse
|
4
|
Chang YS, Lin CL, Lee CW, Lin HC, Wu YT, Shih YH. Exercise Normalized the Hippocampal Renin-Angiotensin System and Restored Spatial Memory Function, Neurogenesis, and Blood-Brain Barrier Permeability in the 2K1C-Hypertensive Mouse. Int J Mol Sci 2022; 23:ijms23105531. [PMID: 35628344 PMCID: PMC9146761 DOI: 10.3390/ijms23105531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 05/14/2022] [Accepted: 05/14/2022] [Indexed: 02/04/2023] Open
Abstract
Hypertension is associated with blood-brain barrier alteration and brain function decline. Previously, we established the 2-kidney,1-clip (2K1C) hypertensive mice model by renin-angiotensin system (RAS) stimulating. We found that 2K1C-induced hypertension would impair hippocampus-related memory function and decrease adult hippocampal neurogenesis. Even though large studies have investigated the mechanism of hypertension affecting brain function, there remains a lack of efficient ways to halt this vicious effect. The previous study indicated that running exercise ameliorates neurogenesis and spatial memory function in aging mice. Moreover, studies showed that exercise could normalize RAS activity, which might be associated with neurogenesis impairment. Thus, we hypothesize that running exercise could ameliorate neurogenesis and spatial memory function impairment in the 2K1C-hypertension mice. In this study, we performed 2K1C surgery on eight-weeks-old C57BL/6 mice and put them on treadmill exercise one month after the surgery. The results indicate that running exercise improves the spatial memory and neurogenesis impairment of the 2K1C-mice. Moreover, running exercise normalized the activated RAS and blood-brain barrier leakage of the hippocampus, although the blood pressure was not decreased. In conclusion, running exercise could halt hypertension-induced brain impairment through RAS normalization.
Collapse
Affiliation(s)
- Ying-Shuang Chang
- Department of Anatomy, School of Medicine, College of Medicine, Kaohsiung Medical University, 100, Shih-Chuan 1st Road, Sanmin District, Kaohsiung 80708, Taiwan; (Y.-S.C.); (H.-C.L.)
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, 100, Shih-Chuan 1st Road, Sanmin District, Kaohsiung 80708, Taiwan;
| | - Chih-Lung Lin
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, 100, Shih-Chuan 1st Road, Sanmin District, Kaohsiung 80708, Taiwan;
- Department of Neurosurgery, Kaohsiung Medical University Hospital, 100, Tzyou 1st Road, Sanmin District, Kaohsiung 80756, Taiwan
| | - Chu-Wan Lee
- Department of Nursing, National Tainan Junior College of Nursing, 78, Section 2, Minzu Road, West Central District, Tainan 70043, Taiwan;
| | - Han-Chen Lin
- Department of Anatomy, School of Medicine, College of Medicine, Kaohsiung Medical University, 100, Shih-Chuan 1st Road, Sanmin District, Kaohsiung 80708, Taiwan; (Y.-S.C.); (H.-C.L.)
- Department of Medical Research, Kaohsiung Medical University Hospital, 100, Tzyou 1st Road, Sanmin District, Kaohsiung 80756, Taiwan
| | - Yi-Ting Wu
- Department of Nursing, Tzu Hui Institute of Technology, Pingtung County 92641, Taiwan;
| | - Yao-Hsiang Shih
- Department of Anatomy, School of Medicine, College of Medicine, Kaohsiung Medical University, 100, Shih-Chuan 1st Road, Sanmin District, Kaohsiung 80708, Taiwan; (Y.-S.C.); (H.-C.L.)
- Department of Medical Research, Kaohsiung Medical University Hospital, 100, Tzyou 1st Road, Sanmin District, Kaohsiung 80756, Taiwan
- Correspondence: ; Tel.: +886-7-3121101 (ext. 2144)
| |
Collapse
|
5
|
Senko AN, Overall RW, Silhavy J, Mlejnek P, Malínská H, Hüttl M, Marková I, Fabel KS, Lu L, Stuchlik A, Williams RW, Pravenec M, Kempermann G. Systems genetics in the rat HXB/BXH family identifies Tti2 as a pleiotropic quantitative trait gene for adult hippocampal neurogenesis and serum glucose. PLoS Genet 2022; 18:e1009638. [PMID: 35377872 PMCID: PMC9060359 DOI: 10.1371/journal.pgen.1009638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 05/02/2022] [Accepted: 03/07/2022] [Indexed: 11/19/2022] Open
Abstract
Neurogenesis in the adult hippocampus contributes to learning and memory in the healthy brain but is dysregulated in metabolic and neurodegenerative diseases. The molecular relationships between neural stem cell activity, adult neurogenesis, and global metabolism are largely unknown. Here we applied unbiased systems genetics methods to quantify genetic covariation among adult neurogenesis and metabolic phenotypes in peripheral tissues of a genetically diverse family of rat strains, derived from a cross between the spontaneously hypertensive (SHR/OlaIpcv) strain and Brown Norway (BN-Lx/Cub). The HXB/BXH family is a very well established model to dissect genetic variants that modulate metabolic and cardiovascular diseases and we have accumulated deep phenome and transcriptome data in a FAIR-compliant resource for systematic and integrative analyses. Here we measured rates of precursor cell proliferation, survival of new neurons, and gene expression in the hippocampus of the entire HXB/BXH family, including both parents. These data were combined with published metabolic phenotypes to detect a neurometabolic quantitative trait locus (QTL) for serum glucose and neuronal survival on Chromosome 16: 62.1-66.3 Mb. We subsequently fine-mapped the key phenotype to a locus that includes the Telo2-interacting protein 2 gene (Tti2)-a chaperone that modulates the activity and stability of PIKK kinases. To verify the hypothesis that differences in neurogenesis and glucose levels are caused by a polymorphism in Tti2, we generated a targeted frameshift mutation on the SHR/OlaIpcv background. Heterozygous SHR-Tti2+/- mutants had lower rates of hippocampal neurogenesis and hallmarks of dysglycemia compared to wild-type littermates. Our findings highlight Tti2 as a causal genetic link between glucose metabolism and structural brain plasticity. In humans, more than 800 genomic variants are linked to TTI2 expression, seven of which have associations to protein and blood stem cell factor concentrations, blood pressure and frontotemporal dementia.
Collapse
Affiliation(s)
- Anna N. Senko
- German Center for Neurodegenerative Diseases (DZNE) Dresden, Germany
- CRTD–Center for Regenerative Therapies Dresden, Technische Universität Dresden, Germany
| | - Rupert W. Overall
- German Center for Neurodegenerative Diseases (DZNE) Dresden, Germany
- CRTD–Center for Regenerative Therapies Dresden, Technische Universität Dresden, Germany
| | - Jan Silhavy
- Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Petr Mlejnek
- Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Hana Malínská
- Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Martina Hüttl
- Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Irena Marková
- Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Klaus S. Fabel
- German Center for Neurodegenerative Diseases (DZNE) Dresden, Germany
- CRTD–Center for Regenerative Therapies Dresden, Technische Universität Dresden, Germany
| | - Lu Lu
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - Ales Stuchlik
- Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Robert W. Williams
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - Michal Pravenec
- Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Gerd Kempermann
- German Center for Neurodegenerative Diseases (DZNE) Dresden, Germany
- CRTD–Center for Regenerative Therapies Dresden, Technische Universität Dresden, Germany
| |
Collapse
|
6
|
Droguerre M, Vidal B, Valdebenito M, Mouthon F, Zimmer L, Charvériat M. Impaired Local and Long-Range Brain Connectivity and Visual Response in a Genetic Rat Model of Hyperactivity Revealed by Functional Ultrasound. Front Neurosci 2022; 16:865140. [PMID: 35401075 PMCID: PMC8987929 DOI: 10.3389/fnins.2022.865140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 02/21/2022] [Indexed: 11/13/2022] Open
Abstract
Attention-Deficit hyperactivity disorder (ADHD) is a central nervous system (CNS) disorder frequently associated with other psychiatric disorders. Pathophysiology processes at stake in ADHD are still under investigation and interestingly neuroimaging data points to modulated brain connectivity in patients. The genetic spontaneously hypertensive rat (SHR) model has been widely used to study pathophysiological underpinnings of ADHD and resting-state brain connectivity using functional magnetic resonance imaging. Here, functional ultrasound imaging, a new technique enabling fast measurement of cerebral blood volume (CBV), was used to further characterize resting-state functional connectivity – at both local and long-range – and visual response in SHR. We demonstrated that response to visual stimulation was increased in SHR in the visual cortex and the superior colliculus. They displayed altered long-range functional connectivity between spatially distinct regions. SHR also displayed modulated local connectivity, with strong increases of regional homogeneity in parts of the motor and visual cortex, along with decreases in the secondary cingulate cortex, the superior colliculus and the pretectal area. As CBV is intricately coupled to cerebral activity, these results suggest an abnormal neural activity in the SHR animal model, consistent with previous clinical studies and demonstrate the potential of functional ultrasound imaging as a translational tool in ADHD.
Collapse
Affiliation(s)
| | - Benjamin Vidal
- Theranexus, Lyon, France
- CNRS, UMR 5292, INSERM U1028, Lyon Neuroscience Research Center, Université de Lyon, Université Claude Bernard Lyon 1, Lyon, France
- *Correspondence: Benjamin Vidal,
| | | | | | - Luc Zimmer
- CNRS, UMR 5292, INSERM U1028, Lyon Neuroscience Research Center, Université de Lyon, Université Claude Bernard Lyon 1, Lyon, France
- CERMEP-Imaging Platform, Bron, France
- Hospices Civils de Lyon, Lyon, France
| | | |
Collapse
|
7
|
Regan SL, Williams MT, Vorhees CV. Review of rodent models of attention deficit hyperactivity disorder. Neurosci Biobehav Rev 2022; 132:621-637. [PMID: 34848247 PMCID: PMC8816876 DOI: 10.1016/j.neubiorev.2021.11.041] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 11/22/2021] [Accepted: 11/23/2021] [Indexed: 01/03/2023]
Abstract
Attention deficit hyperactivity disorder (ADHD) is a polygenic neurodevelopmental disorder that affects 8-12 % of children and >4 % of adults. Environmental factors are believed to interact with genetic predispositions to increase susceptibility to ADHD. No existing rodent model captures all aspects of ADHD, but several show promise. The main genetic models are the spontaneous hypertensive rat, dopamine transporter knock-out (KO) mice, dopamine receptor subtype KO mice, Snap-25 KO mice, guanylyl cyclase-c KO mice, and latrophilin-3 KO mice and rats. Environmental factors thought to contribute to ADHD include ethanol, nicotine, PCBs, lead (Pb), ionizing irradiation, 6-hydroxydopamine, neonatal hypoxia, some pesticides, and organic pollutants. Model validation criteria are outlined, and current genetic models evaluated against these criteria. Future research should explore induced multiple gene KOs given that ADHD is polygenic and epigenetic contributions. Furthermore, genetic models should be combined with environmental agents to test for interactions.
Collapse
Affiliation(s)
- Samantha L. Regan
- Neuroscience Graduate Program, University of Cincinnati, Cincinnati, OH 45229
| | - Michael T. Williams
- Department of Pediatrics, University of Cincinnati College of Medicine, and Division of Neurology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229
| | - Charles V. Vorhees
- Department of Pediatrics, University of Cincinnati College of Medicine, and Division of Neurology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229,Corresponding author: Charles V. Vorhees, Ph.D., Div. of Neurology, Cincinnati Children’s Hospital Medical Center, 3333 Burnet Ave., Cincinnati, OH 45229, USA:
| |
Collapse
|
8
|
Tran S, Kuruppu S, Rajapakse NW. Chronic Renin-Angiotensin System Activation Induced Neuroinflammation: Common Mechanisms Underlying Hypertension and Dementia? J Alzheimers Dis 2021; 85:943-955. [PMID: 34897090 DOI: 10.3233/jad-215231] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Hypertension is a major risk factor for the pathogenesis of vascular dementia and Alzheimer's disease. Chronic activation of the renin-angiotensin system (RAS) contributes substantially to neuroinflammation. We propose that neuroinflammation arising from chronic RAS activation can initiate and potentiate the onset of hypertension and related dementia. Neuroinflammation induced by chronic activation of the RAS plays a key role in the pathogenesis of dementia. Increased levels of pro-inflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and transforming growth factor (TGF)-β have been reported in brain tissue of vascular dementia patients and animal models of vascular dementia induced by either angiotensin II infusion or transverse aortic coarctation. It is proposed that neuronal cell death and synaptic dysfunction induced by neuroinflammation lead to cognitive impairment in dementia. The neuroprotective RAS pathway, regulated by angiotensin-converting enzyme 2 (ACE2) which converts angiotensin II into angiotensin-(1-7), can attenuate hypertension and dementia. Furthermore, the use of anti-hypertensive medications in preventing dementia or cognitive decline in hypertensive patients and animal models of dementia have mostly been beneficial. Current evidence suggests a strong link between RAS induced neuroinflammation and the onset of hypertension and dementia, which warrants further investigation. Strategies to counteract an overactive RAS and enhance the neuroprotective arm of the RAS may help prevent or improve cognitive impairment associated with hypertension.
Collapse
Affiliation(s)
- Shirley Tran
- School of Biomedical Sciences, University of Queensland, St. Lucia, QLD, Australia
| | - Sanjaya Kuruppu
- School of Biomedical Sciences, University of Queensland, St. Lucia, QLD, Australia.,Department of Biochemistry & Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Niwanthi W Rajapakse
- School of Biomedical Sciences, University of Queensland, St. Lucia, QLD, Australia
| |
Collapse
|
9
|
Lee C, Wu D, Chen S, Lin Y, Lee T. Exercise intensities modulate cognitive function in spontaneously hypertensive rats through oxidative mediated synaptic plasticity in hippocampus. J Cell Mol Med 2021; 25:8546-8557. [PMID: 34328702 PMCID: PMC8419173 DOI: 10.1111/jcmm.16816] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 06/13/2021] [Accepted: 07/15/2021] [Indexed: 12/28/2022] Open
Abstract
Oxidative damage in the brain may lead to cognitive impairments. There was considerable debate regarding the beneficial effects of physical exercise on cognitive functions because exercise protocols have varied widely across studies. We investigated whether different exercise intensities alter performance on cognitive tasks. The experiment was performed on spontaneously hypertensive rats (6 months at the established phase of hypertension) distributed into 3 groups: sedentary, low-intensity exercise and high-intensity exercise. Systolic blood pressure measurements confirmed hypertension in spontaneously hypertensive rats. In comparison to normotensive Wistar-Kyoto rats, sedentary spontaneously hypertensive rats had similar escape latencies and a similar preference for the correct quadrant in the probe trial. Compared to the sedentary group, the low-intensity exercise group had significantly better improvements in spatial memory assessed by Morris water maze. Low-intensity exercise was associated with attenuated reactive oxygen species, as measured by dihydroethidine fluorescence and nitrotyrosine staining in the dentate gyrus of the hippocampus. This was coupled with increased numbers of neurons and dendritic spines as well as a significant upregulation of synaptic density. In contrast, the beneficial effects of low-intensity exercise are abolished in high-intensity exercise as shown by increased free radical levels and an impairment in spatial memory. We concluded that exercise is an effective strategy to improve spatial memory in spontaneously hypertensive rats even at an established phase of hypertension. Low-intensity exercise exhibited better improvement on cognitive deficits than high-intensity exercise by attenuating free radical levels and improving downstream synaptic plasticity.
Collapse
Affiliation(s)
| | - De‐Yu Wu
- Catholic Sheng Kung Girls’ High SchoolTainanTaiwan
| | - Syue‐yi Chen
- Cardiovascular InstituteAn Nan HospitalChina Medical UniversityTainanTaiwan
| | - Yi‐Pin Lin
- Department of NeurologyAn Nan HospitalChina Medical UniversityTainanTaiwan
| | - Tsung‐Ming Lee
- Cardiovascular InstituteAn Nan HospitalChina Medical UniversityTainanTaiwan
- Department of MedicineChina Medical UniversityTaichungTaiwan
| |
Collapse
|
10
|
Moti BS, Oz E, Olga A, Bella G, Shifra S, Eilam P. New Cortical Neurodegenerative Pathways in the Hypertensive Rat Brain. Cereb Cortex 2021; 31:5487-5496. [PMID: 34179944 DOI: 10.1093/cercor/bhab173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 04/20/2021] [Accepted: 05/25/2021] [Indexed: 11/12/2022] Open
Abstract
Hypertension is a risk factor for neurodegenerative diseases. We hypothesized that chronic hypertension underlies neurodegeneration. In this study, we examined the expression of brain cortical proteins involved in homeostasis, apoptosis, and brain functions in Spontaneously Hypertensive Rats (SHR) compared with normotensive Wistar-Kyoto (WKY) rats. We used paraffin-embedded brain sections of 8-month-old SHR and WKY rats, immunohistochemically stained and analyzed by image processing. In SHR, cytochrome c oxidase subunit 7A increased, indicative of hypoxia; heat shock protein 40, the chaperon for refolding proteins, decreased, leading to accumulation of misfolded proteins; the levels of both voltage-gated sodium channels, Na1.2, 1.6, decreased, reflecting attenuation of the action potential, causing axonal injury; autophagy-related protein 4A (Atg4a), an essential protein of autophagy, decreased, reducing the removal of misfolded proteins; demyelination, the hallmark of neurodegeneration, was shown; modulation of both histone deacetylases 2 and histone acetyltransferase 1 was shown, indicative of altered regulation of gene transcription; increased activated (cleaved) caspase-3, indicative of apoptosis. These new findings suggest that chronic hypertension induces hypoxia and oxidative stress, axonal injury, accelerates the accumulation of misfolded proteins and apoptosis, pathways preceding neurodegeneration.
Collapse
Affiliation(s)
- Ben Shabat Moti
- Galilee Medical Center, Research Institute, PO Box 21, Nahariya 22100, Israel.,The Azrieli Faculty of Medicine, Bar-Ilan University, Safed, Israel
| | - Eliya Oz
- Galilee Medical Center, Research Institute, PO Box 21, Nahariya 22100, Israel.,The Azrieli Faculty of Medicine, Bar-Ilan University, Safed, Israel
| | - Azrilin Olga
- Galilee Medical Center, Research Institute, PO Box 21, Nahariya 22100, Israel.,Neurology Department, Galilee Medical Center, Nahariya, Israel
| | - Gross Bella
- Galilee Medical Center, Research Institute, PO Box 21, Nahariya 22100, Israel.,The Azrieli Faculty of Medicine, Bar-Ilan University, Safed, Israel.,Neurology Department, Galilee Medical Center, Nahariya, Israel
| | - Sela Shifra
- Galilee Medical Center, Research Institute, PO Box 21, Nahariya 22100, Israel.,The Azrieli Faculty of Medicine, Bar-Ilan University, Safed, Israel
| | - Palzur Eilam
- Galilee Medical Center, Research Institute, PO Box 21, Nahariya 22100, Israel
| |
Collapse
|
11
|
Activation of the G Protein-Coupled Estrogen Receptor (GPER) Increases Neurogenesis and Ameliorates Neuroinflammation in the Hippocampus of Male Spontaneously Hypertensive Rats. Cell Mol Neurobiol 2019; 40:711-723. [DOI: 10.1007/s10571-019-00766-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 11/22/2019] [Indexed: 01/20/2023]
|
12
|
Hypertension and Its Impact on Stroke Recovery: From a Vascular to a Parenchymal Overview. Neural Plast 2019; 2019:6843895. [PMID: 31737062 PMCID: PMC6815533 DOI: 10.1155/2019/6843895] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 08/30/2019] [Indexed: 12/14/2022] Open
Abstract
Hypertension is the first modifiable vascular risk factor accounting for 10.4 million deaths worldwide; it is strongly and independently associated with the risk of stroke and is related to worse prognosis. In addition, hypertension seems to be a key player in the implementation of vascular cognitive impairment. Long-term hypertension, complicated or not by the occurrence of ischemic stroke, is often reviewed on its vascular side, and parenchymal consequences are put aside. Here, we sought to review the impact of isolated hypertension or hypertension associated to stroke on brain atrophy, neuron connectivity and neurogenesis, and phenotype modification of microglia and astrocytes. Finally, we discuss the impact of antihypertensive therapies on cell responses to hypertension and functional recovery. This attractive topic remains a focus of continued investigation and stresses the relevance of including this vascular risk factor in preclinical investigations of stroke outcome.
Collapse
|
13
|
Impaired Glymphatic Transport in Spontaneously Hypertensive Rats. J Neurosci 2019; 39:6365-6377. [PMID: 31209176 DOI: 10.1523/jneurosci.1974-18.2019] [Citation(s) in RCA: 127] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 03/31/2019] [Accepted: 05/30/2019] [Indexed: 12/21/2022] Open
Abstract
The glymphatic system is a brainwide CSF transport system that uses the perivascular space for fast inflow of CSF. Arterial pulsations are a major driver of glymphatic CSF inflow, and hypertension that causes vascular pathologies, such as arterial stiffening and perivascular alterations, may impede the inflow. We used dynamic contrast-enhanced MRI to assess the effect of hypertension on glymphatic transport kinetics in male young and adult spontaneously hypertensive (SHR) rats compared with age-matched normotensive Wistar-Kyoto rats (WKY). We anesthetized the rats with dexmedetomidine/isoflurane and infused paramagnetic contrast (Gd-DOTA) into the cisterna magna during dynamic contrast-enhanced MRI to quantify glymphatic transport kinetics. Structural MRI analysis showed that cerebroventricular volumes are larger and brain volumes significantly smaller in SHR compared with WKY rats, regardless of age. We observed ventricular reflux of Gd-DOTA in SHR rats only, indicating abnormal CSF flow dynamics secondary to innate hydrocephalus. One-tissue compartment analysis revealed impeded glymphatic transport of Gd-DOTA in SHR compared with WKY rats in both age groups, implying that glymphatic transport, including solute clearance from brain parenchyma, is impaired during evolving hypertension in young SHR, an effect that worsens in states of chronic hypertension. The study demonstrates the suppression of glymphatic clearance in SHR rats and thus offers new insight into the coexistence of hypertension and concomitant vascular pathologies in Alzheimer's disease. The study further highlights the importance of considering the distribution of tracers in the CSF compartment in the analysis of the glymphatic system.SIGNIFICANCE STATEMENT The glymphatic system contributes to the removal of amyloid β from the brain and is disrupted in Alzheimer's disease and aging. Using a rat model of hypertension, we measured gross CSF flow and tracked glymphatic influx and efflux rates with dynamic contrast-enhanced MRI, showing that glymphatic transport is compromised in both early and advanced stages of hypertension. The study provides a new perspective on the importance for brain metabolite and fluid homeostasis of maintaining healthy blood vessels, an increasingly pertinent issue in an aging population that in part may explain the link between vascular pathology and Alzheimer's disease.
Collapse
|
14
|
Raz L, Bhaskar K, Weaver J, Marini S, Zhang Q, Thompson JF, Espinoza C, Iqbal S, Maphis NM, Weston L, Sillerud LO, Caprihan A, Pesko JC, Erhardt EB, Rosenberg GA. Hypoxia promotes tau hyperphosphorylation with associated neuropathology in vascular dysfunction. Neurobiol Dis 2018; 126:124-136. [PMID: 30010004 DOI: 10.1016/j.nbd.2018.07.009] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 06/11/2018] [Accepted: 07/10/2018] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Hypertension-induced microvascular brain injury is a major vascular contributor to cognitive impairment and dementia. We hypothesized that chronic hypoxia promotes the hyperphosphorylation of tau and cell death in an accelerated spontaneously hypertensive stroke prone rat model of vascular cognitive impairment. METHODS Hypertensive male rats (n = 13) were fed a high salt, low protein Japanese permissive diet and were compared to Wistar Kyoto control rats (n = 5). RESULTS Using electron paramagnetic resonance oximetry to measure in vivo tissue oxygen levels and magnetic resonance imaging to assess structural brain damage, we found compromised gray (dorsolateral cortex: p = .018) and white matter (corpus callosum: p = .016; external capsule: p = .049) structural integrity, reduced cerebral blood flow (dorsolateral cortex: p = .005; hippocampus: p < .001; corpus callosum: p = .001; external capsule: p < .001) and a significant drop in cortical oxygen levels (p < .05). Consistently, we found reduced oxygen carrying neuronal neuroglobin (p = .008), suggestive of chronic cerebral hypoperfusion in high salt-fed rats. We also observed a corresponding increase in free radicals (NADPH oxidase: p = .013), p-Tau (pThr231) in dorsolateral cortex (p = .011) and hippocampus (p = .003), active interleukin-1β (p < .001) and neurodegeneration (dorsolateral cortex: p = .043, hippocampus: p = .044). Human patients with subcortical ischemic vascular disease, a type of vascular dementia (n = 38; mean age = 68; male/female ratio = 23/15) showed reduced hippocampal volumes and cortical shrinking (p < .05) consistent with the neuronal cell death observed in our hypertensive rat model as compared to healthy controls (n = 47; mean age = 63; male/female ratio = 18/29). CONCLUSIONS Our data support an association between hypertension-induced vascular dysfunction and the sporadic occurrence of phosphorylated tau and cell death in the rat model, correlating with patient brain atrophy, which is relevant to vascular disease.
Collapse
Affiliation(s)
- Limor Raz
- Department of Neurology, 1 University of New Mexico Health Sciences Center, Albuquerque, NM 87131, United States.
| | - Kiran Bhaskar
- Department of Neurology, 1 University of New Mexico Health Sciences Center, Albuquerque, NM 87131, United States; Department of Molecular Genetics and Microbiology, 1 University of New Mexico Health Sciences Center, Albuquerque, NM 87131, United States.
| | - John Weaver
- BRaIN Imaging Center, 1 University of New Mexico Health Sciences Center, Albuquerque, NM 87131, United States.
| | - Sandro Marini
- Center for Genomic Medicine, Massachusetts General Hospital, 185 Cambridge Street, Boston, MA 02114, United States.
| | - Quanguang Zhang
- Department of Neuroscience and Regenerative Medicine, Department of Neurology, Augusta University, 1120 15th Street, Augusta, GA 30912, United States.
| | - Jeffery F Thompson
- Department of Neurology, 1 University of New Mexico Health Sciences Center, Albuquerque, NM 87131, United States.
| | - Candice Espinoza
- Department of Neurology, 1 University of New Mexico Health Sciences Center, Albuquerque, NM 87131, United States.
| | - Sulaiman Iqbal
- Department of Neurology, 1 University of New Mexico Health Sciences Center, Albuquerque, NM 87131, United States.
| | - Nicole M Maphis
- Department of Molecular Genetics and Microbiology, 1 University of New Mexico Health Sciences Center, Albuquerque, NM 87131, United States.
| | - Lea Weston
- Department of Molecular Genetics and Microbiology, 1 University of New Mexico Health Sciences Center, Albuquerque, NM 87131, United States.
| | - Laurel O Sillerud
- Department of Neurology, 1 University of New Mexico Health Sciences Center, Albuquerque, NM 87131, United States; MIND Research Network, 1 University of New Mexico Health Sciences Center, Albuquerque, NM 87131, United States.
| | - Arvind Caprihan
- MIND Research Network, 1 University of New Mexico Health Sciences Center, Albuquerque, NM 87131, United States.
| | - John C Pesko
- Department of Mathematics and Statistics, 1 University of New Mexico Health Sciences Center, Albuquerque, NM 87131, United States
| | - Erik B Erhardt
- Department of Mathematics and Statistics, 1 University of New Mexico Health Sciences Center, Albuquerque, NM 87131, United States.
| | - Gary A Rosenberg
- Department of Neurology, 1 University of New Mexico Health Sciences Center, Albuquerque, NM 87131, United States.
| |
Collapse
|
15
|
Pistikova A, Brozka H, Bencze M, Radostova D, Vales K, Stuchlik A. The effect of hypertension on adult hippocampal neurogenesis in young adult spontaneously hypertensive rats and Dahl rats. Physiol Res 2017; 66:881-887. [PMID: 28730828 DOI: 10.33549/physiolres.933562] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The dentate gyrus of the hippocampus is one of the few places in the brain where neurogenesis occurs in adulthood. Nowadays, an increasing number of children and young adults are affected by hypertension, one of the factors in the development of cerebrovascular diseases and age-related cognitive deficits. Since these cognitive deficits are often hippocampus-dependent, it is possible that hypertension exerts this effect via decreasing adult neurogenesis which has been shown to be essential for a range of cognitive tasks. We used spontaneously hypertensive rats, which develop hypertension in the first weeks of life. Half of them were treated with the antihypertensive drug captopril. We found that the drug-induced lowering of blood pressure in this period did not affect the rate of adult neurogenesis. In a second experiment, we used another animal model of hypertension - salt-sensitive and salt-resistant strains of Dahl rats. A high-salt diet induces hypertension in the salt-sensitive strain, but not in the salt-resistant strain. The high-salt diet led to salt-induced hypertension, but did not affect the level of adult neurogenesis in the dentate gyrus of the hippocampus. We conclude that hypertension does not significantly affect the rate of hippocampal neurogenesis in young adult rats.
Collapse
Affiliation(s)
- A Pistikova
- Department of Neurophysiology of Memory, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic. or
| | | | | | | | | | | |
Collapse
|
16
|
Ragaeva DS, Tikhonova MA, Petrova OM, Igonina TN, Rozkova IN, Brusentsev EY, Amstislavskaya TG, Amstislavsky SY. Neonatal reflexes and behavior in hypertensive rats of ISIAH strain. Physiol Behav 2017; 175:22-30. [PMID: 28341233 DOI: 10.1016/j.physbeh.2017.03.026] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Revised: 02/10/2017] [Accepted: 03/19/2017] [Indexed: 02/08/2023]
Abstract
Hypertension is one of the most common diseases in humans, and there is a special concern on the consequences of maternal hypertensive conditions for the health of newborns. An inherited stress-induced arterial hypertension (ISIAH) rat strain has been selected but only a few studies have addressed behavior in these rats. Body weight, neurodevelopmental reflexes, and neuronal density in the hippocampus were compared in ISIAH and normotensive WAG rats during their suckling period. Systolic and diastolic blood pressure (SBP, DBP), adult rat performance in the open field (OF), elevated plus maze (EPM), and novel object recognition (NOR) tests were evaluated at the age of 12-14weeks old. Body weight in pups did not differ significantly during the suckling period, while adult ISIAH rats were heavier than age-matched WAG rats and possessed the increased SBP and DBP. ISIAH pups were developmentally more advanced than WAG as indicated by grasp reflex and negative geotaxis reaction scores. This was associated with higher neuronal density in CA1 and CA3 hippocampal areas in ISIAH pups on postnatal day 6 as compared to WAG rats. Adult ISIAH rats demonstrated an increased locomotor and exploratory activity in the OF and EPM tests as well as low levels of anxiety. The NOR test revealed no significant difference in recognition but confirmed higher exploratory activity in ISIAH rats compared to WAG rats. The results indicate that hypertensive ISIAH rats feature accelerated development during their suckling period, and as adults, they are more active and less anxious than normotensive WAG rats.
Collapse
Affiliation(s)
- Diana S Ragaeva
- Federal State Budgetary Scientific Institution "Federal Research Center Institute of Cytology and Genetics", Novosibirsk 630090, Russia
| | - Maria A Tikhonova
- Federal State Budgetary Scientific Institution "Federal Research Center Institute of Cytology and Genetics", Novosibirsk 630090, Russia; Federal State Budgetary Scientific Institution "Scientific Research Institute of Physiology and Basic Medicine", Novosibirsk 630117, Russia; Novosibirsk State University, Novosibirsk 630090, Russia
| | - Olga M Petrova
- Federal State Budgetary Scientific Institution "Federal Research Center Institute of Cytology and Genetics", Novosibirsk 630090, Russia; Novosibirsk State University, Novosibirsk 630090, Russia
| | - Tatjana N Igonina
- Federal State Budgetary Scientific Institution "Federal Research Center Institute of Cytology and Genetics", Novosibirsk 630090, Russia
| | - Irina N Rozkova
- Federal State Budgetary Scientific Institution "Federal Research Center Institute of Cytology and Genetics", Novosibirsk 630090, Russia
| | - Eugeny Yu Brusentsev
- Federal State Budgetary Scientific Institution "Federal Research Center Institute of Cytology and Genetics", Novosibirsk 630090, Russia
| | - Tamara G Amstislavskaya
- Federal State Budgetary Scientific Institution "Federal Research Center Institute of Cytology and Genetics", Novosibirsk 630090, Russia; Federal State Budgetary Scientific Institution "Scientific Research Institute of Physiology and Basic Medicine", Novosibirsk 630117, Russia; Novosibirsk State University, Novosibirsk 630090, Russia
| | - Sergey Ya Amstislavsky
- Federal State Budgetary Scientific Institution "Federal Research Center Institute of Cytology and Genetics", Novosibirsk 630090, Russia.
| |
Collapse
|
17
|
Marins FR, Iddings JA, Fontes MAP, Filosa JA. Evidence that remodeling of insular cortex neurovascular unit contributes to hypertension-related sympathoexcitation. Physiol Rep 2017; 5:e13156. [PMID: 28270592 PMCID: PMC5350170 DOI: 10.14814/phy2.13156] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Accepted: 01/18/2017] [Indexed: 11/24/2022] Open
Abstract
The intermediate region of the posterior insular cortex (intermediate IC) mediates sympathoexcitatory responses to the heart and kidneys. Previous studies support hypertension-evoked changes to the structure and function of neurons, blood vessels, astrocytes and microglia, disrupting the organization of the neurovascular unit (NVU). In this study, we evaluated the functional and anatomical integrity of the NVU at the intermediate IC in the spontaneously hypertensive rat (SHR) and its control the Wistar-Kyoto (WKY). Under urethane anesthesia, NMDA microinjection (0.2 mmol/L/100 nL) was performed at the intermediate IC with simultaneous recording of renal sympathetic nerve activity (RSNA), heart rate (HR) and mean arterial pressure (MAP). Alterations in NVU structure were investigated by immunofluorescence for NMDA receptors (NR1), blood vessels (70 kDa FITC-dextran), astrocytes (GFAP), and microglia (Iba1). Injections of NMDA into intermediate IC of SHR evoked higher amplitude responses of RSNA, MAP, and HR On the other hand, NMDA receptor blockade decreased baseline RSNA, MAP and HR in SHR, with no changes in WKY Immunofluorescence data from SHR intermediate IC showed increased NMDA receptor density, contributing to the SHR enhanced sympathetic responses, and increased in vascular density (increased number of branches and endpoints, reduced average branch length), suggesting angiogenesis. Additionally, IC from SHR presented increased GFAP immunoreactivity and contact between astrocyte processes and blood vessels. In SHR, IC microglia skeleton analysis supports their activation (reduced number of branches, junctions, endpoints and process length), suggesting an inflammatory process in this region. These findings indicate that neurogenic hypertension in SHR is accompanied by marked alterations to the NVU within the IC and enhanced NMDA-mediated sympathoexcitatory responses likely contributors of the maintenance of hypertension.
Collapse
Affiliation(s)
- Fernanda R Marins
- Departamento de Fisiologia e Biofísica, INCT, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | | | - Marco A P Fontes
- Departamento de Fisiologia e Biofísica, INCT, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | | |
Collapse
|
18
|
Lu J, Guo Y, Guo CQ, Shi XM, Du NY, Zhao RL, Du WP, Liang JR, Zhu SP, Chen H. Acupuncture with reinforcing and reducing twirling manipulation inhibits hippocampal neuronal apoptosis in spontaneously hypertensive rats. Neural Regen Res 2017; 12:770-778. [PMID: 28616034 PMCID: PMC5461615 DOI: 10.4103/1673-5374.206648] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
To observe the effects of different acupuncture manipulations on blood pressure and target organ damage in spontaneously hypertensive rats (SHRs), this study used the reinforcing twirling method (1.5–2-mm depth; rotating needle clockwise for 360° and then counter clockwise for 360°, with the thumb moving heavily forward and gently backward, 60 times per minute for 1 minute, and retaining needle for 9 minutes), the reducing twirling method (1.5–2-mm depth; rotating needle counter clockwise for 360° and then clockwise for 360°, with the thumb moving heavily backward and gently forward, 60 times per minute for 1 minute, and retaining needle for 9 minutes), and the needle retaining method (1.5–2-mm depth and retaining the needle for 10 minutes). Bilateral Taichong (LR3) was treated by acupuncture using different manipulations and manual stimulation. Reinforcing twirling, reducing twirling, and needle retaining resulted in a decreased number of apoptotic cells, reduced Bax mRNA and protein expression, and an increased Bcl-2/Bax ratio in the hippocampus compared with the SHR group. Among these groups, the Bcl-2/Bax protein ratio was highest in the reducing twirling group, and the Bcl-2/Bax mRNA ratio was highest in the needle retaining group. These results suggest that reinforcing twirling, reducing twirling, and needle retaining methods all improve blood pressure and prevent target organ damage by increasing the hippocampal Bcl-2/Bax ratio and inhibiting cell apoptosis in the hippocampus in SHR.
Collapse
Affiliation(s)
- Juan Lu
- First Hospital Affiliated to Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Yan Guo
- Collage of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China
| | - Chang-Qing Guo
- First Hospital Affiliated to Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Xue-Min Shi
- Collage of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China
| | - Ning-Yu Du
- First Hospital Affiliated to Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Rui-Li Zhao
- First Hospital Affiliated to Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Wen-Ping Du
- Shijiazhuang Hospital of Traditional Chinese Medicine, Shijiazhuang, Hebei Province, China
| | - Jing-Rong Liang
- First Hospital Affiliated to Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Shi-Peng Zhu
- Second School of Clinical Medicine of Nanjing University of Traditional Chinese Medicine, Nanjing, Jiangsu Province, China
| | - Huan Chen
- Department of Acupuncture and Moxibustion, Jiangsu Province Hospital, Nanjing, Jiangsu Province, China
| |
Collapse
|
19
|
Pietranera L, Correa J, Brocca ME, Roig P, Lima A, Di Giorgio N, Garcia-Segura LM, De Nicola AF. Selective Oestrogen Receptor Agonists Rescued Hippocampus Parameters in Male Spontaneously Hypertensive Rats. J Neuroendocrinol 2016; 28. [PMID: 27517478 DOI: 10.1111/jne.12415] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 08/09/2016] [Accepted: 08/10/2016] [Indexed: 12/21/2022]
Abstract
Spontaneously hypertensive rats (SHR) show pronounced hippocampus alterations, including low brain-derived neurotrophic factor (BDNF) expression, reduced neurogenesis, astrogliosis and increased aromatase expression. These changes are reverted by treatment with 17β-oestradiol. To determine which oestradiol receptor (ER) type is involved in these neuroprotective effects, we used agonists of the ERα [propylpyrazole triol (PPT)] and the ERβ [diarylpropionitrite (DPN)] given over 2 weeks to 4-month-old male SHR. Wistar Kyoto normotensive rats served as controls. Using immunocytochemistry, we determined glial fibrillary protein (GFAP)+ astrocytes in the CA1, CA3 and hilus of the dentate gyrus of the hippocampus, aromatase immunostaining in the hilus, and doublecortin (DCX)+ neuronal progenitors in the inner granular zone of the dentate gyrus. Brain-derived neurotrophic factor mRNA was also measured in the hippocampus by the quantitative polymerase chain reaction. In SHR, PPT had no effect on blood pressure, decreased astrogliosis, slightly increased BDNF mRNA, had no effect on the number of DCX+ progenitors, and increased aromatase staining. Treatment with DPN decreased blood pressure, decreased astrogliosis, increased BDNF mRNA and DCX+ progenitors, and did not modify aromatase staining. We hypothesise that, although both receptor types may participate in the previously reported beneficial effects of 17β-oestradiol in SHR, receptor activation with DPN may preferentially facilitate BDNF mRNA expression and neurogenesis. The results of the present study may help in the design of ER-based neuroprotection for the encephalopathy of hypertension.
Collapse
Affiliation(s)
- L Pietranera
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina
- Department of Human Biochemistry, Faculty of Medicine, University of Buenos Aires, Buenos Aires, Argentina
| | - J Correa
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina
| | - M E Brocca
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina
| | - P Roig
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina
| | - A Lima
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina
| | - N Di Giorgio
- Laboratory of Neuroendocrinology, Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina
| | - L M Garcia-Segura
- Instituto Cajal, Consejo Superior de Investigaciones Cientificas, Madrid, Spain
| | - A F De Nicola
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina.
- Department of Human Biochemistry, Faculty of Medicine, University of Buenos Aires, Buenos Aires, Argentina.
| |
Collapse
|
20
|
Relationships of peripheral IGF-1, VEGF and BDNF levels to exercise-related changes in memory, hippocampal perfusion and volumes in older adults. Neuroimage 2016; 131:142-54. [DOI: 10.1016/j.neuroimage.2015.10.084] [Citation(s) in RCA: 184] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2015] [Revised: 10/25/2015] [Accepted: 10/29/2015] [Indexed: 12/30/2022] Open
|
21
|
Inter-Strain Differences in Default Mode Network: A Resting State fMRI Study on Spontaneously Hypertensive Rat and Wistar Kyoto Rat. Sci Rep 2016; 6:21697. [PMID: 26898170 PMCID: PMC4761976 DOI: 10.1038/srep21697] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 01/28/2016] [Indexed: 01/24/2023] Open
Abstract
Genetic divergences among mammalian strains are presented phenotypically in various aspects of physical appearance such as body shape and facial features. Yet how genetic diversity is expressed in brain function still remains unclear. Functional connectivity has been shown to be a valuable approach in characterizing the relationship between brain functions and behaviors. Alterations in the brain default mode network (DMN) have been found in human neuropsychological disorders. In this study we selected the spontaneously hypertensive rat (SHR) and the Wistar Kyoto rat (WKY), two inbred rat strains with close genetic origins, to investigate variations in the DMN. Our results showed that the major DMN differences are the activities in hippocampal area and caudate putamen region. This may be correlated to the hyperactive behavior of the SHR strain. Advanced animal model studies on variations in the DMN may have potential to shed new light on translational medicine, especially with regard to neuropsychological disorders.
Collapse
|
22
|
Li Y, Liu J, Gao D, Wei J, Yuan H, Niu X, Zhang Q. Age-related changes in hypertensive brain damage in the hippocampi of spontaneously hypertensive rats. Mol Med Rep 2016; 13:2552-60. [PMID: 26846626 PMCID: PMC4768967 DOI: 10.3892/mmr.2016.4853] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 01/06/2016] [Indexed: 02/07/2023] Open
Abstract
The aim of the present study was to investigate the age-related alterations in hypertensive brain damage in the hippocampi of spontaneously hypertensive rats (SHR) and the underlying mechanisms. Aging resulted in a significant increase in the number of activated astrocytes and apoptotic cells in the SHR group, which was accompanied by increased expression of oxidative stress markers (iNOS and gp47phox) and apoptotic regulatory proteins (Bax and caspase-3). In addition, the expression of PPAR-γ and Bcl-2 were progressively reduced with increasing age in the SHR group. The 32 and 64-week-old SHRs exhibited significantly increased numbers of apoptotic cells, oxidative stress markers and pro-apoptotic proteins compared with age-matched WKY rats, which was accompanied by reduced expression of PPAR-γ. Compared with the 16 and 32-week-old WKY group, the 64-week-old WKY rats exhibited increased oxidative stress and pro-apoptotic markers, and increased levels apoptotic cells. In conclusion, the present study indicated that both aging and hypertension enhanced brain damage and oxidative stress injury in the hippocampi of SHRs, indicated by an increased presence of apoptotic cells and astrocytes. In addition, reduced expression of PPAR-γ may contribute to the age-related brain damage in SHRs.
Collapse
Affiliation(s)
- Yali Li
- Department of Rehabilitation, The Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China
| | - Jian Liu
- Department of Physiology, School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
| | - Dengfeng Gao
- Department of Cardiology, The Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China
| | - Jin Wei
- Department of Cardiology, The Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China
| | - Haifeng Yuan
- Department of Rehabilitation, The Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China
| | - Xiaolin Niu
- Department of Cardiology, The Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China
| | - Qiaojun Zhang
- Department of Rehabilitation, The Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China
| |
Collapse
|
23
|
Ueno M, Chiba Y, Matsumoto K, Murakami R, Fujihara R, Kawauchi M, Miyanaka H, Nakagawa T. Blood-brain barrier damage in vascular dementia. Neuropathology 2015; 36:115-24. [DOI: 10.1111/neup.12262] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 09/12/2015] [Accepted: 09/13/2015] [Indexed: 12/13/2022]
Affiliation(s)
- Masaki Ueno
- Department of Pathology and Host Defense, Faculty of Medicine; Kagawa University; Kagawa Japan
| | - Yoichi Chiba
- Department of Pathology and Host Defense, Faculty of Medicine; Kagawa University; Kagawa Japan
| | - Koichi Matsumoto
- Department of Pathology and Host Defense, Faculty of Medicine; Kagawa University; Kagawa Japan
| | - Ryuta Murakami
- Department of Pathology and Host Defense, Faculty of Medicine; Kagawa University; Kagawa Japan
| | - Ryuji Fujihara
- Department of Pathology and Host Defense, Faculty of Medicine; Kagawa University; Kagawa Japan
| | - Machi Kawauchi
- Department of Pathology and Host Defense, Faculty of Medicine; Kagawa University; Kagawa Japan
| | | | | |
Collapse
|
24
|
Kasparek T, Theiner P, Filova A. Neurobiology of ADHD From Childhood to Adulthood: Findings of Imaging Methods. J Atten Disord 2015; 19:931-43. [PMID: 24097847 DOI: 10.1177/1087054713505322] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVE To review the pattern of morphological and functional brain changes in both children and adults with ADHD that emerges from the recent literature. In addition, the task of the present review is to explore how to understand the nature of the brain changes. METHODS Literature review. RESULTS Neuroimaging studies provide a multitude of information that currently allows us to expand the notions of ADHD neurobiology beyond its traditional understanding as a manifestation of frontostriatal dysfunction. They point to disorders of several other areas of the brain, particularly the anterior cingulum, the dorsolateral as well as ventrolateral prefrontal cortex, the orbitofrontal cortex, the superior parietal regions, the caudate nucleus, the thalamus, the amygdala and the cerebellum. Imaging studies point to the persistence of changes in both brain structure and function into adulthood, although there might be a tendency for improvement of caudate nucleus pathology. Changes in neuronal (dendritic) plasticity, which are under the modulatory influence of the dopaminergic system, may be in the background of disorders of brain morphology and anatomical connectivity with subsequent brain dysfunction. Growing evidence suggest that methylphenidate treatment can lead to improvement of brain changes seen in neuroimaging by its positive effect on neuroplasticity. CONCLUSION Changes in neuronal plasticity may be behind persisting brain changes in ADHD. Current treatment approaches seem to improve these neuroplastic processes, and, therefore, may have a positive effect on the neuropathology of ADHD.
Collapse
Affiliation(s)
- Tomas Kasparek
- Masaryk University, Brno, Czech Republic University Hospital Brno, Czech Republic
| | - Pavel Theiner
- Masaryk University, Brno, Czech Republic University Hospital Brno, Czech Republic
| | | |
Collapse
|
25
|
Pietranera L, Brocca ME, Roig P, Lima A, Garcia-Segura LM, De Nicola AF. Estrogens are neuroprotective factors for hypertensive encephalopathy. J Steroid Biochem Mol Biol 2015; 146:15-25. [PMID: 24736028 DOI: 10.1016/j.jsbmb.2014.04.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Revised: 04/04/2014] [Accepted: 04/07/2014] [Indexed: 10/25/2022]
Abstract
Estrogens are neuroprotective factors for brain diseases, including hypertensive encephalopathy. In particular, the hippocampus is highly damaged by high blood pressure, with several hippocampus functions being altered in humans and animal models of hypertension. Working with a genetic model of primary hypertension, the spontaneously hypertensive rat (SHR), we have shown that SHR present decreased dentate gyrus neurogenesis, astrogliosis, low expression of brain derived neurotrophic factor (BDNF), decreased number of neurons in the hilus of the dentate gyrus, increased basal levels of the estrogen-synthesizing enzyme aromatase, and atrophic dendritic arbor with low spine density in the CA1 region compared to normotensive Wistar Kyoto (WKY) ratsl. Changes also occur in the hypothalamus of SHR, with increased expression of the hypertensinogenic peptide arginine vasopressin (AVP) and its V1b receptor. Following chronic estradiol treatment, SHR show decreased blood pressure, enhanced hippocampus neurogenesis, decreased the reactive astrogliosis, increased BDNF mRNA and protein expression in the dentate gyrus, increased neuronal number in the hilus of the dentate gyrus, further increased the hyperexpression of aromatase and replaced spine number with remodeling of the dendritic arbor of the CA1 region. We have detected by qPCR the estradiol receptors ERα and ERβ in hippocampus from both SHR and WKY rats, suggesting direct effects of estradiol on brain cells. We hypothesize that a combination of exogenously given estrogens plus those locally synthesized by estradiol-stimulated aromatase may better alleviate the hippocampal and hypothalamic encephalopathy of SHR. This article is part of a Special Issue entitled "Sex steroids and brain disorders".
Collapse
Affiliation(s)
- Luciana Pietranera
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental, Obligado 2490, 1428 Buenos Aires, Argentina; Department of Human Biochemistry, Faculty of Medicine, University of Buenos Aires, Paraguay 2155, 1425 Buenos Aires, Argentina
| | - Maria Elvira Brocca
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental, Obligado 2490, 1428 Buenos Aires, Argentina
| | - Paulina Roig
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental, Obligado 2490, 1428 Buenos Aires, Argentina
| | - Analia Lima
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental, Obligado 2490, 1428 Buenos Aires, Argentina
| | - Luis Miguel Garcia-Segura
- Instituto Cajal, Consejo Superior de Investigaciones Cientificas, Avenida Doctor Arce 37, E-28002 Madrid, Spain
| | - Alejandro F De Nicola
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental, Obligado 2490, 1428 Buenos Aires, Argentina; Department of Human Biochemistry, Faculty of Medicine, University of Buenos Aires, Paraguay 2155, 1425 Buenos Aires, Argentina.
| |
Collapse
|
26
|
Brocca M, Pietranera L, Roig P, Lima A, De Nicola A. Effects of 17β-estradiol on the cytoarchitecture of pyramidal CA1 neurons in normoglycemic and diabetic male spontaneously hypertensive rats. Neuroscience 2014; 280:243-53. [DOI: 10.1016/j.neuroscience.2014.09.030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Revised: 08/25/2014] [Accepted: 09/11/2014] [Indexed: 12/20/2022]
|
27
|
Pietranera L, Brocca ME, Roig P, Lima A, Garcia-Segura LM, De Nicola AF. 17α-Oestradiol-induced neuroprotection in the brain of spontaneously hypertensive rats. J Neuroendocrinol 2014; 26:310-20. [PMID: 24730417 DOI: 10.1111/jne.12151] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Revised: 02/20/2014] [Accepted: 03/16/2014] [Indexed: 11/27/2022]
Abstract
17β-oestradiol is a powerful neuroprotective factor for the brain abnormalities of spontaneously hypertensive rats (SHR). 17α-Oestradiol, a nonfeminising isomer showing low affinity for oestrogen receptors, is also endowed with neuroprotective effects in vivo and in vitro. We therefore investigated whether treatment with 17α-oestradiol prevented pathological changes of the hippocampus and hypothalamus of SHR. We used 20-week-old male SHR with a blood pressure of approximately 170 mmHg receiving s.c. a single 800 μg pellet of 17α-oestradiol dissolved in cholesterol or vehicle only for 2 weeks Normotensive Wistar-Kyoto (WKY) rats were used as controls. 17α-Oestradiol did not modify blood pressure, serum prolactin, 17β-oestradiol levels or the weight of the testis and pituitary of SHR. In the brain, we analysed steroid effects on hippocampus Ki67+ proliferating cells, doublecortin (DCX) positive neuroblasts, glial fibrillary acidic protein (GFAP)+ astrocyte density, aromatase immunostaining and brain-derived neurotrophic factor (BDNF) mRNA. In the hypothalamus, we determined arginine vasopressin (AVP) mRNA. Treatment of SHR with 17α-oestradiol enhanced the number of Ki67+ in the subgranular zone and DCX+ cells in the inner granule cell layer of the dentate gyrus, increased BDNF mRNA in the CA1 region and gyrus dentatus, decreased GFAP+ astrogliosis in the CA1 subfield, and decreased hypothalamic AVP mRNA. Aromatase expression was unmodified. By contrast to SHR, normotensive WKY rats were unresponsive to 17α-oestradiol. These data indicate a role for 17α-oestradiol as a protective factor for the treatment of hypertensive encephalopathy. Furthermore, 17α-oestradiol is weakly oestrogenic in the periphery and can be used in males.
Collapse
Affiliation(s)
- L Pietranera
- Laboratory of Neuroendocrine Biochemistry, Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina; Department of Human Biochemistry, Faculty of Medicine, University of Buenos Aires, Buenos Aires, Argentina
| | | | | | | | | | | |
Collapse
|
28
|
Neuroprotective activity of thioctic acid in central nervous system lesions consequent to peripheral nerve injury. BIOMED RESEARCH INTERNATIONAL 2013; 2013:985093. [PMID: 24527432 PMCID: PMC3914604 DOI: 10.1155/2013/985093] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 11/25/2013] [Accepted: 11/25/2013] [Indexed: 11/21/2022]
Abstract
Peripheral neuropathies are heterogeneous disorders presenting often with hyperalgesia and allodynia. This study has assessed if chronic constriction injury (CCI) of sciatic nerve is accompanied by increased oxidative stress and central nervous system (CNS) changes and if these changes are sensitive to treatment with thioctic acid. Thioctic acid is a naturally occurring antioxidant existing in two optical isomers (+)- and (−)-thioctic acid and in the racemic form. It has been proposed for treating disorders associated with increased oxidative stress. Sciatic nerve CCI was made in spontaneously hypertensive rats (SHRs) and in normotensive reference cohorts. Rats were untreated or treated intraperitoneally for 14 days with (+/−)-, (+)-, or (−)-thioctic acid. Oxidative stress, astrogliosis, myelin sheets status, and neuronal injury in motor and sensory cerebrocortical areas were assessed. Increase of oxidative stress markers, astrogliosis, and neuronal damage accompanied by a decreased expression of neurofilament were observed in SHR. This phenomenon was more pronounced after CCI. Thioctic acid countered astrogliosis and neuronal damage, (+)-thioctic acid being more active than (+/−)- or (−)-enantiomers. These findings suggest a neuroprotective activity of thioctic acid on CNS lesions consequent to CCI and that the compound may represent a therapeutic option for entrapment neuropathies.
Collapse
|
29
|
Bender AR, Daugherty AM, Raz N. Vascular Risk Moderates Associations between Hippocampal Subfield Volumes and Memory. J Cogn Neurosci 2013; 25:1851-62. [DOI: 10.1162/jocn_a_00435] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Abstract
Advanced age and vascular risk negatively affect episodic memory. The hippocampus (HC) is a complex structure, and little is known about the roles of different HC regions in age-related memory declines. Using data from an ongoing longitudinal study, we investigated whether memory functions are related to volumes of specific HC subregions (CA1-2, CA3-4/dentate gyrus, and subiculum). Furthermore, we inquired if arterial hypertension, a common age-related vascular risk factor, modifies age-related differences in HC regional volumes, concurrent memory performance, and improvement in memory over multiple administrations. Healthy adults (n = 49, 52–82 years old) completed associative recognition and free recall tasks. In grouped path models, covariance structures differed between hypertensive and normotensive participants. Whereas larger CA3-4/dentate gyrus volumes predicted greater improvement in associative memory over repeated tests regardless of vascular risk, CA1-2 volumes were associated with improvement in noun recall only in hypertensive participants. Only among hypertensive participants, CA1-2 volumes negatively related to age and CA3-4/dentate gyrus and CA1-2 volumes were associated with performance at the last measurement occasion. These findings suggest that relatively small regions of the HC may play a role in age-related memory declines and that vascular risk factors associated with advanced age may modify that relationship.
Collapse
|
30
|
Tian GH, Sun K, Huang P, Zhou CM, Yao HJ, Huo ZJ, Hao HF, Yang L, Pan CS, He K, Fan JY, Li ZG, Han JY. Long-Term Stimulation with Electroacupuncture at DU20 and ST36 Rescues Hippocampal Neuron through Attenuating Cerebral Blood Flow in Spontaneously Hypertensive Rats. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE : ECAM 2013; 2013:482947. [PMID: 23662137 PMCID: PMC3626240 DOI: 10.1155/2013/482947] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2013] [Revised: 03/10/2013] [Accepted: 03/14/2013] [Indexed: 01/10/2023]
Abstract
This study was designed to investigate the effect of long-term electroacupuncture at Baihui (DU20) and Zusanli (ST36) on cerebral microvessels and neurons in CA1 region of hippocampus in spontaneously hypertensive rats (SHR). A total of 45 male Wistar rats and 45 SHR were randomly grouped, with or without electroacupuncture (EA) at DU20 and ST36, once every other day for a period of 8 weeks. The mean arterial pressure (MAP) was measured once every 2 weeks. Cerebral blood flow (CBF) and the number of open microvessels in hippocampal CA1 region were detected by Laser Doppler and immunohistochemistry, respectively. Nissl staining and Western blotting were performed, respectively, to determine hippocampus morphology and proteins that were implicated in the concerning signaling pathways. The results showed that the MAP in SHR increased linearly over the observation period and was significantly reduced following electroacupuncture as compared with sham control SHR rats, while no difference was observed in Wistar rats between EA and sham control. The CBF, learning and memory capacity, and capillary rarefaction of SHR were improved by EA. The upregulation of angiotensin II type I receptor (AT1R), endothelin receptor (ETAR), and endothelin-1 (ET-1) in SHR rats was attenuated by electroacupuncture, suggesting an implication of AT1R, ETAR, and ET-1 pathway in the effect of EA.
Collapse
Affiliation(s)
- Gui-Hua Tian
- School of Acupuncture and Moxibustion, Beijing University of Chinese Medicine, Beijing 100029, China
- Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, Beijing 101121, China
- Tasly Microcirculation Research Center, Peking University Health Science Center, Beijing 100191, China
| | - Kai Sun
- Tasly Microcirculation Research Center, Peking University Health Science Center, Beijing 100191, China
- Key Laboratory of Microcirculation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing 100191, China
| | - Ping Huang
- Tasly Microcirculation Research Center, Peking University Health Science Center, Beijing 100191, China
- Key Laboratory of Microcirculation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing 100191, China
| | - Chang-Man Zhou
- Tasly Microcirculation Research Center, Peking University Health Science Center, Beijing 100191, China
- Department of Anatomy, School of Basic Medical Sciences, Peking University, Beijing 100191, China
| | - Hai-Jiang Yao
- School of Acupuncture and Moxibustion, Beijing University of Chinese Medicine, Beijing 100029, China
| | - Ze-Jun Huo
- School of Acupuncture and Moxibustion, Beijing University of Chinese Medicine, Beijing 100029, China
| | - Hui-Feng Hao
- Tasly Microcirculation Research Center, Peking University Health Science Center, Beijing 100191, China
- Key Laboratory of Microcirculation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing 100191, China
- Department of Integration of Chinese and Western Medicine, School of Basic Medical Sciences, Peking University, Beijing 100191, China
| | - Lei Yang
- Department of Anatomy, School of Basic Medical Sciences, Peking University, Beijing 100191, China
| | - Chun-Shui Pan
- Tasly Microcirculation Research Center, Peking University Health Science Center, Beijing 100191, China
- Key Laboratory of Microcirculation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing 100191, China
| | - Ke He
- Tasly Microcirculation Research Center, Peking University Health Science Center, Beijing 100191, China
- Key Laboratory of Microcirculation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing 100191, China
- Department of Integration of Chinese and Western Medicine, School of Basic Medical Sciences, Peking University, Beijing 100191, China
| | - Jing-Yu Fan
- Tasly Microcirculation Research Center, Peking University Health Science Center, Beijing 100191, China
- Key Laboratory of Microcirculation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing 100191, China
| | - Zhi-Gang Li
- School of Acupuncture and Moxibustion, Beijing University of Chinese Medicine, Beijing 100029, China
| | - Jing-Yan Han
- Tasly Microcirculation Research Center, Peking University Health Science Center, Beijing 100191, China
- Key Laboratory of Microcirculation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing 100191, China
- Department of Integration of Chinese and Western Medicine, School of Basic Medical Sciences, Peking University, Beijing 100191, China
| |
Collapse
|
31
|
Brain activity of thioctic Acid enantiomers: in vitro and in vivo studies in an animal model of cerebrovascular injury. Int J Mol Sci 2013; 14:4580-95. [PMID: 23443159 PMCID: PMC3634420 DOI: 10.3390/ijms14034580] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Revised: 02/19/2013] [Accepted: 02/20/2013] [Indexed: 01/27/2023] Open
Abstract
Oxidative stress is an imbalance between the production of free radicals and antioxidant defense mechanisms, potentially leading to tissue damage. Oxidative stress has a key role in the development of cerebrovascular and/or neurodegenerative diseases. This phenomenon is mainly mediated by an enhanced superoxide production by the vascular endothelium with its consequent dysfunction. Thioctic, also known as alpha-lipoic acid (1,2-dithiolane-3-pentanoic acid), is a naturally occurring antioxidant that neutralizes free radicals in the fatty and watery regions of cells. Both the reduced and oxidized forms of the compound possess antioxidant ability. Thioctic acid has two optical isomers designated as (+)- and (−)-thioctic acid. Naturally occurring thioctic acid is the (+)-thioctic acid form, but the synthetic compound largely used in the market for stability reasons is a mixture of (+)- and (−)-thioctic acid. The present study was designed to compare the antioxidant activity of the two enantiomers versus the racemic form of thioctic acid on hydrogen peroxide-induced apoptosis in a rat pheochromocytoma PC12 cell line. Cell viability was evaluated by MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and free oxygen radical species (ROS) production was assessed by flow cytometry. Antioxidant activity of the two enantiomers and the racemic form of thioctic acid was also evaluated in spontaneously hypertensive rats (SHR) used as an in vivo model of increased oxidative stress. A 3-h exposure of PC12 cells to hydrogen peroxide (H2O2) significantly decreased cell viability and increased levels of intracellular ROS production. Pre-treatment with racemic thioctic acid or (+)-enantiomer significantly inhibited H2O2-induced decrease in cell viability from the concentration of 50 μmol/L and 20 μmol/L, respectively. Racemic thioctic acid and (+)-salt decreased levels of intracellular ROS, which were unaffected by (−)-thioctic acid. In the brain of SHR, the occurrence of astrogliosis and neuronal damage, with a decreased expression of neurofilament 200 kDa were observed. Treatment of SHR for 30 days with (+)-thioctic acid reduced the size of astrocytes and increased the neurofilament immunoreaction. The above findings could contribute to clarify the role played by thioctic acid in central nervous system injury related to oxidative stress. The more pronounced effect of (+)-thioctic acid observed in this study may have practical therapeutic implications worthy of being investigated in further preclinical and clinical studies.
Collapse
|
32
|
Pietranera L, Brocca ME, Cymeryng C, Gomez-Sanchez E, Gomez-Sanchez CE, Roig P, Lima A, De Nicola AF. Increased expression of the mineralocorticoid receptor in the brain of spontaneously hypertensive rats. J Neuroendocrinol 2012; 24:1249-58. [PMID: 22564091 DOI: 10.1111/j.1365-2826.2012.02332.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The mineralocorticoid receptor (MR) has been considered as both neuroprotective and damaging to the function of the central nervous system. MR may be also involved in central regulation of blood pressure. In the present study, we compared the expression of MR and the glucocorticoid receptor (GR) in the hippocampus and hypothalamus of 16-week-old spontaneously hypertensive rats (SHR) and normotensive control Wistar Kyoto (WKY) rats. In the hippocampus, MR expression was studied by in situ hybridization (ISH), quantitative polymerase chain reaction (PCR) and immunohistochemistry, whereas GR expression was analysed using the latter two procedures. Hypertensive animals showed an increased expression of MR mRNA in the whole hippocampus according to qPCR data and also in CA3 by ISH. Immunocytochemical staining for MR of the dorsal hippocampus, however, did not reveal differences between SHR and WKY rats. SHR showed elevated hypothalamic MR mRNA by qPCR, as well as an increased number of MR immunopositive cells in the magnocellular paraventricular region, compared to WKY rats. By contrast, expression levels of GR mRNA or protein in the hippocampus and hypothalamus of SHR were similar to those of WKY rats. Furthermore, we investigated the role of MR in the hypertensive rats by i.c.v. injection of the MR antagonist RU-2831. This compound produced a significant drop in blood pressure for SHR. In conclusion, MR expression is increased in the hippocampus and hypothalamus of SHR. We suggest that pathological MR overdrive may take responsibility for up-regulation of blood pressure and the encephalopathy of hypertension.
Collapse
Affiliation(s)
- L Pietranera
- Institute of Biology and Experimental Medicine, CONICET, Obligado, Buenos Aires, Argentina
| | | | | | | | | | | | | | | |
Collapse
|
33
|
Li Y, Duan Z, Gao D, Huang S, Yuan H, Niu X. The new role of LOX-1 in hypertension induced neuronal apoptosis. Biochem Biophys Res Commun 2012; 425:735-40. [PMID: 22885180 DOI: 10.1016/j.bbrc.2012.07.143] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Accepted: 07/26/2012] [Indexed: 02/07/2023]
Abstract
Lectin-like oxidized low-density lipoprotein (oxLDL) receptor-1 (LOX-1) was originally identified as a receptor for oxLDL predominantly expressed in endothelial cells. Recently up-regulation of LOX-1 has been implicated in oxidative stress and cell apoptosis in many cell types. However, LOX-1 expression in neurons or regulation of neuronal apoptosis by LOX-1 has not been reported. To investigate the possible roles of LOX-1 in hypertension induced brain damage, we examined the distribution of LOX-1 in cortex and hippocampus and compared its expression in 32-week-old SHR and WKY rats. Immunofluorescence revealed that LOX-1 positive cells were located principally at the cortex involved in sensory information processing and were mainly expressed in neurons. We also found up-regulated mRNA expression of LOX-1, Bax and caspase-3 and down-regulated mRNA expression of Bcl-2 in SHR group. Compared with WKY group, SHR group showed increased LOX-1 positive cells and TUNEL positive cells. Furthermore, double-labeling method indicated that LOX-1 expression was colocalized with TUNEL positive cells, which means that LOX-1 expression was involved in hypertension related cell apoptosis. These findings indicated that LOX-1 expression was up-regulated in the cortex of SHR and its expression has implication in neuronal apoptosis. Elevated Bax/Bcl-2 ratio may be involved under this event.
Collapse
Affiliation(s)
- Yali Li
- Department of Cardiology, The Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, China
| | | | | | | | | | | |
Collapse
|
34
|
Tayebati SK, Tomassoni D, Amenta F. Spontaneously hypertensive rat as a model of vascular brain disorder: microanatomy, neurochemistry and behavior. J Neurol Sci 2012; 322:241-9. [PMID: 22726353 DOI: 10.1016/j.jns.2012.05.047] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2012] [Accepted: 05/23/2012] [Indexed: 11/28/2022]
Abstract
Arterial hypertension is the main risk factor for stroke and plays a role in the development of vascular cognitive impairment (VCI) and vascular dementia (VaD). An association between hypertension and reduced cerebral blood flow and VCI is documented and arterial hypertension in midlife is associated with a higher probability of cognitive impairment. These findings suggest that arterial hypertension is a main cause of vascular brain disorder (VBD). Spontaneously hypertensive rat (SHR) is the rat strain most extensively investigated and used for assessing hypertensive brain damage and treatment of it. They are normotensive at birth and at 6months they have a sustained hypertension. Time-dependent rise of arterial blood pressure, the occurrence of brain atrophy, loss of nerve cells and glial reaction are phenomena shared to some extent with hypertensive brain damage in humans. SHR present changes of some neurotransmitter systems that may have functional and behavioral relevance. An impaired cholinergic neurotransmission characterizes SHR, similarly as reported in patients affected by VaD. SHR are also characterized by a dopaminergic hypofunction and noradrenergic hyperactivity similarly as occurs in attention-deficit with hyperactivity disorder (ADHD). Microanatomical, neurochemical and behavioral data on SHR are in favor of the hypothesis that this strain is a suitable model of VBD. Changes in catecholaminergic transmission put forward SHR as a possible model of ADHD as well. Hence SHR could represent a multi-faced model of two important groups of pathologies, VBD and ADHD. As for most models, researchers should always consider that SHR offer some similarities with corresponding human pathologies, but they do not suffer from the same disease. This paper reviews the main microanatomical, neurochemical and behavioral characteristics of SHR with particular reference as an animal model of brain vascular injury.
Collapse
Affiliation(s)
- Seyed Khosrow Tayebati
- School of Medicinal Sciences and Health Products, University of Camerino, Camerino, Italy.
| | | | | |
Collapse
|
35
|
Goo MJ, Choi SM, Kim SH, Ahn BO. Protective effects of acetyl-L-carnitine on neurodegenarative changes in chronic cerebral ischemia models and learning-memory impairment in aged rats. Arch Pharm Res 2012; 35:145-54. [PMID: 22297753 DOI: 10.1007/s12272-012-0116-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Revised: 07/14/2011] [Accepted: 07/25/2011] [Indexed: 11/30/2022]
Abstract
This study investigated the effects of acetyl-L-carnitine (ALC) in secondarily-induced cerebral chronic ischemia models using rats with permanent ligation of bilateral common carotid arteries (BCCL) and spontaneously hypertensive rats (SHR). Additionally, we used normal aged rats as a primary dementia model. Chronic ALC administration at 100 mg/kg (p.o.) for 4 weeks significantly attenuated neurodegenerative changes. In groups receiving 50 mg/kg or 100 mg/kg, ALC inhibited the active astrocyte increase in cerebral tissues of both BCCL and SHR models. In BCCL rats, ALC administration (50 mg/kg or 100 mg/kg, p.o.) resulted in significant promotion of glutathione levels in brain tissues. We also confirmed behavioral improvement after ALC treatment (100 mg/kg for 8 weeks, p.o.) on learning-memory function using aged rats (18 months old) in a passive avoidance task and preservation of CA1 pyramidal neurons was coincided on histopathological observation. In conclusion, chronic ALC administration may ameliorate cerebral ischemia progress after a cerebrovascular disorder as well as spontaneous ageing-related cerebral dysfunction via hippocampal protection.
Collapse
Affiliation(s)
- Moon-Jung Goo
- Preclinical Research Laboratories, Dong-A Pharmaceutical Company, Yongin 446-905, Korea.
| | | | | | | |
Collapse
|
36
|
Ueno M, Nakagawa T, Nagai Y, Nishi N, Kusaka T, Kanenishi K, Onodera M, Hosomi N, Huang C, Yokomise H, Tomimoto H, Sakamoto H. The expression of CD36 in vessels with blood-brain barrier impairment in a stroke-prone hypertensive model. Neuropathol Appl Neurobiol 2011; 37:727-37. [DOI: 10.1111/j.1365-2990.2011.01172.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
|
37
|
Russell VA. Overview of animal models of attention deficit hyperactivity disorder (ADHD). ACTA ACUST UNITED AC 2011; Chapter 9:Unit9.35. [PMID: 21207367 DOI: 10.1002/0471142301.ns0935s54] [Citation(s) in RCA: 97] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Attention-deficit/hyperactivity disorder (ADHD) is a heterogeneous, highly heritable, behavioral disorder that affects ∼5% to 10% of children worldwide. Although animal models cannot truly reflect human psychiatric disorders, they can provide insight into the disorder that cannot be obtained from human studies because of the limitations of available techniques. Genetic models include the spontaneously hypertensive rat (SHR), the Naples High Excitability (NHE) rat, poor performers in the 5-choice serial reaction time (5-CSRT) task, the dopamine transporter (DAT) knock-out mouse, the SNAP-25 deficient mutant coloboma mouse, mice expressing a human mutant thyroid hormone receptor, a nicotinic receptor knock-out mouse, and a tachykinin-1 (NK1) receptor knock-out mouse. Chemically induced models of ADHD include prenatal or early postnatal exposure to ethanol, nicotine, polychlorinated biphenyls, or 6-hydroxydopamine (6-OHDA). Environmentally induced models have also been suggested; these include neonatal anoxia and rat pups reared in social isolation. The major insight provided by animal models was the consistency of findings regarding the involvement of dopaminergic, noradrenergic, and sometimes also serotonergic systems, as well as more fundamental defects in neurotransmission.
Collapse
Affiliation(s)
- Vivienne Ann Russell
- Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Observatory, South Africa
| |
Collapse
|
38
|
Bennett M. The prefrontal–limbic network in depression: A core pathology of synapse regression. Prog Neurobiol 2011; 93:457-67. [DOI: 10.1016/j.pneurobio.2011.01.001] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Revised: 12/10/2010] [Accepted: 01/03/2011] [Indexed: 01/06/2023]
|
39
|
Pietranera L, Bellini M, Arévalo M, Goya R, Brocca M, Garcia-Segura L, De Nicola A. Increased aromatase expression in the hippocampus of spontaneously hypertensive rats: effects of estradiol administration. Neuroscience 2011; 174:151-9. [DOI: 10.1016/j.neuroscience.2010.11.044] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2010] [Revised: 11/04/2010] [Accepted: 11/20/2010] [Indexed: 12/26/2022]
|
40
|
Sánchez F, Gómez-Villalobos MDJ, Juarez I, Quevedo L, Flores G. Dendritic morphology of neurons in medial prefrontal cortex, hippocampus, and nucleus accumbens in adult SH rats. Synapse 2010; 65:198-206. [DOI: 10.1002/syn.20837] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
|
41
|
Hsu JW, Lee LC, Chen RF, Yen CT, Chen YS, Tsai ML. Striatal volume changes in a rat model of childhood attention-deficit/hyperactivity disorder. Psychiatry Res 2010; 179:338-41. [PMID: 20493538 DOI: 10.1016/j.psychres.2009.08.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2009] [Revised: 08/20/2009] [Accepted: 08/21/2009] [Indexed: 01/26/2023]
Abstract
Attention-deficit/hyperactivity disorder (ADHD) is one of the most common childhood neuropsychiatric disorders. Based on neuroimaging studies, the striatum is reported to be abnormal in size, but it is still not clear how they change during developmental stages. Spontaneously hypertensive rats (SHRs) are the commonly used animal model for ADHD. We investigated volume differences of the striatum at various ages before puberty in SHRs versus a control strain, Wistar-Kyoto rats (WKYs). Volumes of the bilateral striatum were measured using micrographs of Nissl-stained serial sections in both strains of rats at the ages of 4, 5, 6, 7, 8, 9, and 10weeks (n=4, each strain at each age). The results demonstrated that the age of a significant striatal volume difference between SHRs and WKYs was 5weeks; however, there was no significant difference for the corresponding total brain volume at each matched age. It suggested that the timing for striatal abnormalities in ADHD occurs during an early stage of childhood.
Collapse
Affiliation(s)
- Ju-Wei Hsu
- Department of Psychiatry, Taipei Veterans General Hospital, Taipei, Taiwan
| | | | | | | | | | | |
Collapse
|
42
|
Maller JJ, Réglade-Meslin C, Chan P, Daskalakis ZJ, Thomson RHS, Anstey KJ, Budge M, Sachdev P, Fitzgerald PB. Hippocampal sulcal cavities: prevalence, risk factors and relationship to memory impairment. Brain Res 2010; 1368:222-30. [PMID: 21040716 DOI: 10.1016/j.brainres.2010.10.089] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2010] [Revised: 10/18/2010] [Accepted: 10/24/2010] [Indexed: 02/02/2023]
Abstract
While hippocampal volumes have been extensively examined in neuropsychiatric disorders and ageing, small areas of signal variation within the hippocampus commonly observed on MRI, described as hippocampal sulcal cavities (HSCs), have received less attention. We review the published literature on HSCs to examine their prevalence, putative aetiological factors such as hypertension, and possible cognitive correlates. HSCs were reported in 77% (66% weighted mean) of patients with memory disorders and 48% (47% weighted mean) of controls, and the prevalence increased with age in healthy subjects (r=0.64, p=0.047). A number of studies reported hypertension as a risk factor, and related their presence to poorer memory function. Further work is needed to fully understand the clinical significance of these lesions.
Collapse
Affiliation(s)
- Jerome J Maller
- Monash Alfred Psychiatry Research Centre, The Alfred & Monash University School of Psychology and Psychiatry, Melbourne, Victoria, Australia.
| | | | | | | | | | | | | | | | | |
Collapse
|
43
|
|
44
|
Wells AM, Janes AC, Liu X, Deschepper CF, Kaufman MJ, Kantak KM. Medial temporal lobe functioning and structure in the spontaneously hypertensive rat: comparison with Wistar-Kyoto normotensive and Wistar-Kyoto hypertensive strains. Hippocampus 2010; 20:787-97. [PMID: 19623608 DOI: 10.1002/hipo.20681] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The spontaneously hypertensive rat (SHR) is used as an animal model of attention deficit hyperactivity disorder (ADHD). It displays deficits in frontostriatal functioning, but it is unclear if medial temporal lobe functioning and structure are affected. We used behavioral tasks that evaluate functioning of the amygdala and hippocampus to compare male SHR to male rats from two inbred comparator strains, the normotensive Wistar-Kyoto (WKY) and the hypertensive Wistar-Kyoto (WKHT) rat (n = 8/strain). The three strains showed similar levels of amygdala-related stimulus-reward learning during conditioned cue preference testing. In the ambiguous T-maze task, which dissociates between spatial and habit learning, significantly more WKHT than SHR or WKY used a response (indicative of habit learning) versus a place (indicative of spatial learning) strategy during an early probe test on day 8. During a later probe test on day 24, WKY progressed significantly from using a place strategy to a response strategy. Throughout all probe tests, a place strategy was used predominately by SHR and a response strategy by WKHT. Thus, SHR exhibited deficits in dorsal striatum-related habit learning, whereas WKHT exhibited deficits in hippocampus-related spatial learning. Following behavioral testing, fluid attenuated inversion recovery (FLAIR) magnetic resonance imaging scans were conducted in subgroups of rats from each strain (n = 4/strain). FLAIR imaging detected bilateral hippocampal hyperintensities in three of four WKHT and unilateral hippocampal atrophy in one of four SHR. The association between response strategy use during the initial probe test to forage for food in the ambiguous T-maze task and bilateral hippocampal abnormalities was significant. Collectively, while medial temporal lobe functioning appears to be normal in SHR exhibiting an ADHD-like phenotype, WKHT rats display both hippocampal functioning deficits and signs of bilateral hippocampal cell loss. The latter characteristics might be used to develop a new animal model of age- or disease-related decline in hippocampal functioning.
Collapse
Affiliation(s)
- Audrey M Wells
- Department of Psychology, Program in Neuroscience and CELEST Science of Learning Center, Boston University, Boston, Massachusetts 02215, USA
| | | | | | | | | | | |
Collapse
|
45
|
The expression of LDL receptor in vessels with blood–brain barrier impairment in a stroke-prone hypertensive model. Histochem Cell Biol 2010; 133:669-76. [DOI: 10.1007/s00418-010-0705-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/03/2010] [Indexed: 01/30/2023]
|
46
|
Kelsen J, Larsen MH, Sørensen JC, Møller A, Frøkiaer J, Nielsen S, Nyengaard JR, Mikkelsen JD, Rønn LCB. Neuronal precursor cell proliferation in the hippocampus after transient cerebral ischemia: a comparative study of two rat strains using stereological tools. EXPERIMENTAL & TRANSLATIONAL STROKE MEDICINE 2010; 2:8. [PMID: 20370927 PMCID: PMC2868803 DOI: 10.1186/2040-7378-2-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2009] [Accepted: 04/06/2010] [Indexed: 01/19/2023]
Abstract
Background We are currently investigating microglial activation and neuronal precursor cell (NPC) proliferation after transient middle cerebral artery occlusion (tMCAo) in rats. This study aimed: (1) to investigate differences in hippocampal NPC proliferation in outbred male spontaneously hypertensive rats (SHRs) and Sprague-Dawley rats (SDs) one week after tMCAo; (2) to present the practical use of the optical fractionator and 2D nucleator in stereological brain tissue analyses; and (3) to report our experiences with an intraluminal tMCAo model where the occluding filament is advanced 22 mm beyond the carotid bifurcation and the common carotid artery is clamped during tMCAo. Methods Twenty-three SDs and twenty SHRs were randomized into four groups subjected to 90 minutes tMCAo or sham. BrdU (50 mg/kg) was administered intraperitoneally twice daily on Day 4 to 7 after surgery. On Day 8 all animals were euthanized. NeuN-stained tissue sections were used for brain and infarct volume estimation with the 2D nucleator and Cavalieri principle. Brains were studied for the presence of activated microglia (ED-1) and hippocampal BrdU incorporation using the optical fractionator. Results We found no significant difference or increase in post-ischemic NPC proliferation between the two strains. However, the response to remote ischemia may differ between SDs and SHRs. In three animals increased post-stroke NPC proliferation was associated with hippocampal ischemic injury. The mean infarct volume was 89.2 ± 76.1 mm3 in SHRs and 16.9 ± 22.7 mm3 in SDs (p < 0.005). Eight out of eleven SHRs had ischemic neocortical damage in contrast to only one out of 12 SDs. We observed involvement of the anterior choroidal and hypothalamic arteries in several animals from both strains and the anterior cerebral artery in two SHRs. Conclusions We found no evidence of an early hippocampal NPC proliferation one week after tMCAo in both strains. Infarction within the anterior choroidal artery could induce hippocampal ischemia and increase NPC proliferation profoundly. NPC proliferation was not aggravated by the presence of activated microglia. Intraluminal tMCAo in SHRs gave a more reliable infarct with neocortical involvement, but affected territories supplied by the anterior cerebral, anterior choroidal and hypothalamic arteries.
Collapse
Affiliation(s)
- Jesper Kelsen
- The Water and Salt Research Centre, University of Aarhus, DK-8000 Aarhus C, Denmark.
| | | | | | | | | | | | | | | | | |
Collapse
|
47
|
Expression of aquaporins 1 and 4 in the brain of spontaneously hypertensive rats. Brain Res 2010; 1325:155-63. [PMID: 20156423 DOI: 10.1016/j.brainres.2010.02.023] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Revised: 02/05/2010] [Accepted: 02/06/2010] [Indexed: 11/20/2022]
Abstract
Aquaporins (AQP) 1 and 4 are water channel proteins localized respectively at the level of the blood-cerebrospinal fluids (CSF) and blood brain (BBB) barriers. These barriers represent the sites of exchange between blood and nervous tissue and between blood, choroid plexus and CSF in brain ventricles respectively. Damage of these barriers may alter transfer of substances between blood and nervous tissue. In spontaneously hypertensive rats (SHR) chronic hypertension may induce BBB dysfunction and pronounced defects in the integrity of the blood-CSF barrier. AQP1 is expressed in the apical membrane of choroid plexus epithelium. AQP4 is expressed by astrocyte foot processes near blood vessels. The present study has assessed the expression of AQP1 and AQP4 in the brain of SHR in pre-hypertensive (2 months of age), developing hypertension (4 months of age) and established hypertension (6 months of age) stages. Age-matched Wistar-Kyoto (WKY) rats were used as normotensive reference group. AQP1 expression is increased in choroid plexus epithelium of 6-month-old SHR. An increased expression of AQP4 was found in frontal cortex, striatum, and hippocampus of 4- and 6-month-old SHR compared to younger cohorts and age-matched WKY rats. These findings suggest that the increase in AQP expression may alter fluid exchange in BBB and/or in blood-CSF barrier. This situation in case of an acute or excessively elevated rise of blood pressure can promote BBB changes causing the brain damage occurring in this animal model of hypertension.
Collapse
|
48
|
Neuroprotective effect of treatment with galantamine and choline alphoscerate on brain microanatomy in spontaneously hypertensive rats. J Neurol Sci 2009; 283:187-94. [DOI: 10.1016/j.jns.2009.02.349] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
|
49
|
Ueno M, Nakagawa T, Huang CL, Ueki M, Kusaka T, Hosomi N, Kanenishi K, Onodera M, Wu B, Sakamoto H. The expression of P-glycoprotein is increased in vessels with blood-brain barrier impairment in a stroke-prone hypertensive model. Neuropathol Appl Neurobiol 2009; 35:147-55. [PMID: 19284476 DOI: 10.1111/j.1365-2990.2008.00966.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
AIMS We previously reported that the blood-brain barrier (BBB) function was impaired in vessels in the hippocampus in 3-month-old stroke-prone spontaneously hypertensive rats (SHRSP). In this study, we examined gene and protein expressions of P-glycoprotein, a representative efflux transporter of cerebral vessels, in the BBB-damaged hippocampal vessels of SHRSP and in the vessels of Wistar Kyoto (WKY) rats as controls, to clarify roles of the efflux transporter in the BBB-damaged vessels. METHODS The expression of P-glycoprotein in hippocampal and cortical samples was examined by real-time quantitative reverse transcriptase-polymerase chain reaction (RT-PCR), Western blotting and immunoelectron microscopic techniques. RESULTS Real-time RT-PCR and Western blotting analyses revealed that the gene and protein expressions of P-glycoprotein were increased in the hippocampal samples of 3-month-old SHRSP compared with hippocampal samples of 3-month-old WKY rats or with cortical samples of SHRSP. The gene expression of P-glycoprotein was also increased in the hippocampal samples of 4-week-old SHRSP. Immunoelectron microscopic examination revealed that immunosignals of P-glycoprotein were seen in the luminal and ab-luminal cytoplasmic membranes of endothelial cells and the basal lamina, that the labelling density of P-glycoprotein in the vessel wall was higher in the hippocampus of 3-month-old SHRSP than in other groups and that the immunosignals of P-glycoprotein were occasionally co-located with those of albumin. CONCLUSIONS These findings indicate that the expression of P-glycoprotein is increased in BBB-damaged hippocampal vessels in hypertensive SHRSP compared with those in WKY rats.
Collapse
Affiliation(s)
- M Ueno
- Department of Pathology and Host Defense, Kagawa University, Kagawa, Japan.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
50
|
The expression of matrix metalloproteinase-13 is increased in vessels with blood–brain barrier impairment in a stroke-prone hypertensive model. Hypertens Res 2009; 32:332-8. [DOI: 10.1038/hr.2009.26] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
|