1
|
Serrano GE, Walker J, Nelson C, Glass M, Arce R, Intorcia A, Cline MP, Nabaty N, Acuña A, Huppert Steed A, Sue LI, Belden C, Choudhury P, Reiman E, Atri A, Beach TG. Correlation of Presynaptic and Postsynaptic Proteins with Pathology in Alzheimer's Disease. Int J Mol Sci 2024; 25:3130. [PMID: 38542104 PMCID: PMC10970005 DOI: 10.3390/ijms25063130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 02/29/2024] [Accepted: 03/01/2024] [Indexed: 04/28/2024] Open
Abstract
Synaptic transmission is essential for nervous system function and the loss of synapses is a known major contributor to dementia. Alzheimer's disease dementia (ADD) is characterized by synaptic loss in the mesial temporal lobe and cerebral neocortex, both of which are brain areas associated with memory and cognition. The association of synaptic loss and ADD was established in the late 1980s, and it has been estimated that 30-50% of neocortical synaptic protein is lost in ADD, but there has not yet been a quantitative profiling of different synaptic proteins in different brain regions in ADD from the same individuals. Very recently, positron emission tomography (PET) imaging of synapses is being developed, accelerating the focus on the role of synaptic loss in ADD and other conditions. In this study, we quantified the densities of two synaptic proteins, the presynaptic protein Synaptosome Associated Protein 25 (SNAP25) and the postsynaptic protein postsynaptic density protein 95 (PSD95) in the human brain, using enzyme-linked immunosorbent assays (ELISA). Protein was extracted from the cingulate gyrus, hippocampus, frontal, primary visual, and entorhinal cortex from cognitively unimpaired controls, subjects with mild cognitive impairment (MCI), and subjects with dementia that have different levels of Alzheimer's pathology. SNAP25 is significantly reduced in ADD when compared to controls in the frontal cortex, visual cortex, and cingulate, while the hippocampus showed a smaller, non-significant reduction, and entorhinal cortex concentrations were not different. In contrast, all brain areas showed lower PSD95 concentrations in ADD when compared to controls without dementia, although in the hippocampus, this failed to reach significance. Interestingly, cognitively unimpaired cases with high levels of AD pathology had higher levels of both synaptic proteins in all brain regions. SNAP25 and PSD95 concentrations significantly correlated with densities of neurofibrillary tangles, amyloid plaques, and Mini Mental State Examination (MMSE) scores. Our results suggest that synaptic transmission is affected by ADD in multiple brain regions. The differences were less marked in the entorhinal cortex and the hippocampus, most likely due to a ceiling effect imposed by the very early development of neurofibrillary tangles in older people in these brain regions.
Collapse
Affiliation(s)
- Geidy E. Serrano
- Civin Laboratory for Neuropathology, Banner Sun Health Research Institute, Sun City, AZ 85351, USA; (J.W.); (R.A.); (A.I.); (M.P.C.); (N.N.); (A.A.); (A.H.S.)
| | - Jessica Walker
- Civin Laboratory for Neuropathology, Banner Sun Health Research Institute, Sun City, AZ 85351, USA; (J.W.); (R.A.); (A.I.); (M.P.C.); (N.N.); (A.A.); (A.H.S.)
| | - Courtney Nelson
- Civin Laboratory for Neuropathology, Banner Sun Health Research Institute, Sun City, AZ 85351, USA; (J.W.); (R.A.); (A.I.); (M.P.C.); (N.N.); (A.A.); (A.H.S.)
| | - Michael Glass
- Civin Laboratory for Neuropathology, Banner Sun Health Research Institute, Sun City, AZ 85351, USA; (J.W.); (R.A.); (A.I.); (M.P.C.); (N.N.); (A.A.); (A.H.S.)
| | - Richard Arce
- Civin Laboratory for Neuropathology, Banner Sun Health Research Institute, Sun City, AZ 85351, USA; (J.W.); (R.A.); (A.I.); (M.P.C.); (N.N.); (A.A.); (A.H.S.)
| | - Anthony Intorcia
- Civin Laboratory for Neuropathology, Banner Sun Health Research Institute, Sun City, AZ 85351, USA; (J.W.); (R.A.); (A.I.); (M.P.C.); (N.N.); (A.A.); (A.H.S.)
| | - Madison P. Cline
- Civin Laboratory for Neuropathology, Banner Sun Health Research Institute, Sun City, AZ 85351, USA; (J.W.); (R.A.); (A.I.); (M.P.C.); (N.N.); (A.A.); (A.H.S.)
| | - Natalie Nabaty
- Civin Laboratory for Neuropathology, Banner Sun Health Research Institute, Sun City, AZ 85351, USA; (J.W.); (R.A.); (A.I.); (M.P.C.); (N.N.); (A.A.); (A.H.S.)
| | - Amanda Acuña
- Civin Laboratory for Neuropathology, Banner Sun Health Research Institute, Sun City, AZ 85351, USA; (J.W.); (R.A.); (A.I.); (M.P.C.); (N.N.); (A.A.); (A.H.S.)
| | - Ashton Huppert Steed
- Civin Laboratory for Neuropathology, Banner Sun Health Research Institute, Sun City, AZ 85351, USA; (J.W.); (R.A.); (A.I.); (M.P.C.); (N.N.); (A.A.); (A.H.S.)
| | - Lucia I. Sue
- Civin Laboratory for Neuropathology, Banner Sun Health Research Institute, Sun City, AZ 85351, USA; (J.W.); (R.A.); (A.I.); (M.P.C.); (N.N.); (A.A.); (A.H.S.)
| | - Christine Belden
- Cleo Roberts Center, Banner Sun Health Research Institute, Sun City, AZ 85351, USA (P.C.)
| | - Parichita Choudhury
- Cleo Roberts Center, Banner Sun Health Research Institute, Sun City, AZ 85351, USA (P.C.)
| | - Eric Reiman
- The Banner Alzheimer’s Institute, Phoenix, AZ 85006, USA
| | - Alireza Atri
- Cleo Roberts Center, Banner Sun Health Research Institute, Sun City, AZ 85351, USA (P.C.)
| | - Thomas G. Beach
- Civin Laboratory for Neuropathology, Banner Sun Health Research Institute, Sun City, AZ 85351, USA; (J.W.); (R.A.); (A.I.); (M.P.C.); (N.N.); (A.A.); (A.H.S.)
| |
Collapse
|
2
|
Immunoproteomics of cow's milk allergy in Mexican pediatric patients. J Proteomics 2023; 273:104809. [PMID: 36587729 DOI: 10.1016/j.jprot.2022.104809] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 12/24/2022] [Accepted: 12/25/2022] [Indexed: 12/31/2022]
Abstract
Immunological mechanisms of non-IgE-mediated cow's milk protein allergy (CMPA) are not well understood. Such a circumstance requires attention with the aim of discovering new biomarkers that could lead to better diagnostic assays for early treatment. Here, we sought both to investigate the mechanism that underlies non-IgE-mediated CMPA and to identify cow's milk immunoreactive proteins in a Mexican pediatric patient group (n = 34). Hence, we determined the IgE and IgG1-4 subclass antibody levels against cow's milk proteins (CMP) by ELISA. Then, we performed 2D-Immunoblots using as first antibody immunoglobulins in the patients'serum that bound specifically against CMP together with CMP enrichment by ion-exchange chromatography. Immunoreactive proteins were identified by mass spectrometry-based proteomics. The serological test confirmed absence of specific IgE in the CMPA patients but showed significant increase in antigen-specific IgG1. Additionally, we identified 11 proteins that specifically bound to IgG1. We conclude that the detection of specific IgG1 together with an immunoproteomics approach is highly relevant to the understanding of CMPA's physiopathology and as a possible aid in making a prognosis since current evidence indicates IgG1 occurrence as an early signal of potential risk toward development of IgE-mediated food allergy. SIGNIFICANCE: Allergies are one of the most studied topics in the field of public health and novel protein allergens are found each year. Discovery of new principal and regional allergens has remarkable repercussions in precise molecular diagnostics, prognostics, and more specific immunotherapies. In this context, specific IgE is widely known to mediate physiopathology; however, allergies whose mechanism does not involve this immunoglobulin are poorly understood although their incidence has increased. Therefore, accurate diagnosis and adequate treatment are delayed with significant consequences on the health of pediatric patients. The study of type and subtypes of immunoglobulins associated with the immunoreactivity of cow's milk proteins together with an immunoproteomics approach allows better comprehension of physiopathology, brings the opportunity to discover new potential cow's milk protein allergens and may help in prognosis prediction (IgG1 occurrence as an early signal of possible risk toward development of IgE-mediated food allergy).
Collapse
|
3
|
Tu H, Zhang ZW, Qiu L, Lin Y, Jiang M, Chia SY, Wei Y, Ng ASL, Reynolds R, Tan EK, Zeng L. Increased expression of pathological markers in Parkinson's disease dementia post-mortem brains compared to dementia with Lewy bodies. BMC Neurosci 2022; 23:3. [PMID: 34983390 PMCID: PMC8725407 DOI: 10.1186/s12868-021-00687-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 12/22/2021] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Parkinson's disease (PD) and dementia with Lewy bodies (DLB) are common age-related neurodegenerative diseases comprising Lewy body spectrum disorders associated with cortical and subcortical Lewy body pathology. Over 30% of PD patients develop PD dementia (PDD), which describes dementia arising in the context of established idiopathic PD. Furthermore, Lewy bodies frequently accompany the amyloid plaque and neurofibrillary tangle pathology of Alzheimer's disease (AD), where they are observed in the amygdala of approximately 60% of sporadic and familial AD. While PDD and DLB share similar pathological substrates, they differ in the temporal onset of motor and cognitive symptoms; however, protein markers to distinguish them are still lacking. METHODS Here, we systematically studied a series of AD and PD pathogenesis markers, as well as mitochondria, mitophagy, and neuroinflammation-related indicators, in the substantia nigra (SN), temporal cortex (TC), and caudate and putamen (CP) regions of human post-mortem brain samples from individuals with PDD and DLB and condition-matched controls. RESULTS We found that p-APPT668 (TC), α-synuclein (CP), and LC3II (CP) are all increased while the tyrosine hydroxylase (TH) (CP) is decreased in both PDD and DLB compared to control. Also, the levels of Aβ42 and DD2R, IBA1, and p-LRRK2S935 are all elevated in PDD compared to control. Interestingly, protein levels of p-TauS199/202 in CP and DD2R, DRP1, and VPS35 in TC are all increased in PDD compared to DLB. CONCLUSIONS Together, our comprehensive and systematic study identified a set of signature proteins that will help to understand the pathology and etiology of PDD and DLB at the molecular level.
Collapse
Affiliation(s)
- Haitao Tu
- Neural Stem Cell Research Lab, Research Department, National Neuroscience Institute, Singapore, 308433, Singapore
| | - Zhi Wei Zhang
- Neural Stem Cell Research Lab, Research Department, National Neuroscience Institute, Singapore, 308433, Singapore
| | - Lifeng Qiu
- Neural Stem Cell Research Lab, Research Department, National Neuroscience Institute, Singapore, 308433, Singapore
| | - Yuning Lin
- Guangxi University of Chinese Medicine, 179 Mingxiu Dong Rd., Nanning, 530001, Guangxi, China
| | - Mei Jiang
- Neural Stem Cell Research Lab, Research Department, National Neuroscience Institute, Singapore, 308433, Singapore
- Department of Anatomy and Neurobiology, Zhongshan School of Medicine, Sun Yat-Sen University, #74, Zhongshan No. 2 Road, Guangzhou, 510080, China
- Department of Human Anatomy, Institute of Stem Cell and Regenerative Medicine, Dongguan Campus, Guangdong Medical University, Dongguan, China
| | - Sook-Yoong Chia
- Neural Stem Cell Research Lab, Research Department, National Neuroscience Institute, Singapore, 308433, Singapore
| | - Yanfei Wei
- Guangxi University of Chinese Medicine, 179 Mingxiu Dong Rd., Nanning, 530001, Guangxi, China
| | - Adeline S L Ng
- Department of Neurology, National Neuroscience Institute, Singapore, 308433, Singapore
- DUKE-NUS Graduate Medical School, Neuroscience & Behavioral Disorders Program, Singapore, 169857, Singapore
| | - Richard Reynolds
- Division of Neuroscience, Imperial College London, Hammersmith Hospital, London, W12 0NN, UK
- Centre for Molecular Neuropathology, Lee Kong Chian School of Medicine, Nanyang Technological University, Novena Campus, 11 Mandalay Road, Singapore, 308232, Singapore
| | - Eng-King Tan
- Department of Neurology, National Neuroscience Institute, Singapore, 308433, Singapore
- DUKE-NUS Graduate Medical School, Neuroscience & Behavioral Disorders Program, Singapore, 169857, Singapore
| | - Li Zeng
- Neural Stem Cell Research Lab, Research Department, National Neuroscience Institute, Singapore, 308433, Singapore.
- DUKE-NUS Graduate Medical School, Neuroscience & Behavioral Disorders Program, Singapore, 169857, Singapore.
- Centre for Molecular Neuropathology, Lee Kong Chian School of Medicine, Nanyang Technological University, Novena Campus, 11 Mandalay Road, Singapore, 308232, Singapore.
| |
Collapse
|
4
|
Lai C, Chen Q, Ding Y, Liu H, Tang Z. Emodin protected against synaptic impairment and oxidative stress induced by fluoride in SH-SY5Y cells by modulating ERK1/2/Nrf2/HO-1 pathway. ENVIRONMENTAL TOXICOLOGY 2020; 35:922-929. [PMID: 32293791 DOI: 10.1002/tox.22928] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 03/09/2020] [Accepted: 03/20/2020] [Indexed: 06/11/2023]
Abstract
Excessive fluoride exposure contributes to neurotoxic effects. Emodin exhibits antioxidative functions in the central nervous system (CNS); however, its neuroprotective mechanism against fluoride remains to be elucidated. Our aim was to explore the neuroprotective efficacy and the possible mechanisms of emodin. In our study, synaptic proteins and oxidative stress damage were examined after human neuroblastoma SH-SY5Y cells were treated with high doses of NaF for 24 hours. Moreover, pretreatment with emodin was used to shed light on the neuroprotective effects in NaF-induced toxicity in SH-SY5Y cells. We found that NaF significantly lowered the protein expressions of SNAP 25, synaptophysin and PSD 95 in SH-SY5Y cells. In addition, NaF exposure increased the protein expression of p-ERK1/2 and decreased the protein expressions of Nrf2 and HO-1, as well as facilitated increasing ROS, 4-hydroxynonenal (4-HNE), and 8-Hydroxy-2'-deoxyguanosine (8-OHdG). Pretreatment with emodin significantly recovered these alterations caused by NaF. These data implied that the neuroprotective effects of emodin and pointed to the promising utilization for protecting against neurotoxicity induced by fluoride.
Collapse
Affiliation(s)
- Chencen Lai
- Clinical Research Center, The First Affliated Hospital of Guizhou University of Traditional Chinese Medicine, Guiyang, Guizhou, China
| | - Qian Chen
- Clinical Research Center, The First Affliated Hospital of Guizhou University of Traditional Chinese Medicine, Guiyang, Guizhou, China
| | - Yuanting Ding
- Clinical Research Center, The First Affliated Hospital of Guizhou University of Traditional Chinese Medicine, Guiyang, Guizhou, China
| | - Heng Liu
- Department of Anesthesiology, Tongren Municipal People's Hospital, Tongren, Guizhou, China
| | - Zhi Tang
- Clinical Research Center, The First Affliated Hospital of Guizhou University of Traditional Chinese Medicine, Guiyang, Guizhou, China
| |
Collapse
|
5
|
The functional microscopic neuroanatomy of the human subthalamic nucleus. Brain Struct Funct 2019; 224:3213-3227. [PMID: 31562531 PMCID: PMC6875153 DOI: 10.1007/s00429-019-01960-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 09/14/2019] [Indexed: 01/19/2023]
Abstract
The subthalamic nucleus (STN) is successfully used as a surgical target for deep brain stimulation in the treatment of movement disorders. Interestingly, the internal structure of the STN is still incompletely understood. The objective of the present study was to investigate three-dimensional (3D) immunoreactivity patterns for 12 individual protein markers for GABA-ergic, serotonergic, dopaminergic as well as glutamatergic signaling. We analyzed the immunoreactivity using optical densities and created a 3D reconstruction of seven postmortem human STNs. Quantitative modeling of the reconstructed 3D immunoreactivity patterns revealed that the applied protein markers show a gradient distribution in the STN. These gradients were predominantly organized along the ventromedial to dorsolateral axis of the STN. The results are of particular interest in view of the theoretical underpinning for surgical targeting, which is based on a tripartite distribution of cognitive, limbic and motor function in the STN.
Collapse
|
6
|
VGF Peptides in Cerebrospinal Fluid of Patients with Dementia with Lewy Bodies. Int J Mol Sci 2019; 20:ijms20194674. [PMID: 31547145 PMCID: PMC6801397 DOI: 10.3390/ijms20194674] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 09/10/2019] [Accepted: 09/16/2019] [Indexed: 12/13/2022] Open
Abstract
In a previous proteomic study, we identified the neurosecretory protein VGF (VGF) as a potential biomarker for dementia with Lewy bodies (DLB). Here, we extended the study of VGF by comparing levels in cerebrospinal fluid (CSF) from 44 DLB patients, 20 Alzheimer’s disease (AD) patients, and 22 cognitively normal controls selected from the Amsterdam Dementia Cohort. CSF was analyzed using two orthogonal analytical methods: (1) In-house-developed quantitative ELISA and (2) selected reaction monitoring (SRM). We further addressed associations of VGF with other CSF biomarkers and cognition. VGF levels were lower in CSF from patients with DLB compared to either AD patients or controls. VGF was positively correlated with CSF tau and α-synuclein (0.55 < r < 0.75), but not with Aβ1-42. In DLB patients, low VGF levels were related to a more advanced cognitive decline at time of first presentation, whereas high levels of VGF were associated with steeper subsequent longitudinal cognitive decline. Hence, CSF VGF levels were lower in DLB compared to both AD and controls across different analytical methods. The strong associations with cognitive decline further points out VGF as a possible disease stage or prognostic marker for DLB.
Collapse
|
7
|
Bereczki E, Branca RM, Francis PT, Pereira JB, Baek JH, Hortobágyi T, Winblad B, Ballard C, Lehtiö J, Aarsland D. Synaptic markers of cognitive decline in neurodegenerative diseases: a proteomic approach. Brain 2019; 141:582-595. [PMID: 29324989 DOI: 10.1093/brain/awx352] [Citation(s) in RCA: 143] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 10/30/2017] [Indexed: 01/12/2023] Open
Abstract
See Attems and Jellinger (doi:10.1093/brain/awx360) for a scientific commentary on this article.Cognitive changes occurring throughout the pathogenesis of neurodegenerative diseases are directly linked to synaptic loss. We used in-depth proteomics to compare 32 post-mortem human brains in the prefrontal cortex of prospectively followed patients with Alzheimer's disease, Parkinson's disease with dementia, dementia with Lewy bodies and older adults without dementia. In total, we identified 10 325 proteins, 851 of which were synaptic proteins. Levels of 25 synaptic proteins were significantly altered in the various dementia groups. Significant loss of SNAP47, GAP43, SYBU (syntabulin), LRFN2, SV2C, SYT2 (synaptotagmin 2), GRIA3 and GRIA4 were further validated on a larger cohort comprised of 92 brain samples using ELISA or western blot. Cognitive impairment before death and rate of cognitive decline significantly correlated with loss of SNAP47, SYBU, LRFN2, SV2C and GRIA3 proteins. Besides differentiating Parkinson's disease dementia, dementia with Lewy bodies, and Alzheimer's disease from controls with high sensitivity and specificity, synaptic proteins also reliably discriminated Parkinson's disease dementia from Alzheimer's disease patients. Our results suggest that these particular synaptic proteins have an important predictive and discriminative molecular fingerprint in neurodegenerative diseases and could be a potential target for early disease intervention.
Collapse
Affiliation(s)
- Erika Bereczki
- Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Division of Neurogeriatrics, Karolinska Institutet, Novum, Stockholm, Sweden
| | - Rui M Branca
- Department of Oncology-Pathology, Science for Life Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Paul T Francis
- King's College London, Wolfson Centre for Age-Related Diseases, London SE1 1UL, UK
| | - Joana B Pereira
- Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Division of Clinical Geriatrics, Karolinska Institutet, Novum, 14186 Stockholm, Sweden
| | - Jean-Ha Baek
- Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Division of Neurogeriatrics, Karolinska Institutet, Novum, Stockholm, Sweden
| | - Tibor Hortobágyi
- MTA-DE Cerebrovascular and Neurodegenerative Research Group, University of Debrecen, Debrecen, Hungary.,Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Bengt Winblad
- Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Division of Neurogeriatrics, Karolinska Institutet, Novum, Stockholm, Sweden
| | - Clive Ballard
- Department of Oncology-Pathology, Science for Life Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Janne Lehtiö
- Department of Oncology-Pathology, Science for Life Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Dag Aarsland
- Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Division of Neurogeriatrics, Karolinska Institutet, Novum, Stockholm, Sweden.,Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| |
Collapse
|
8
|
Synaptic loss in schizophrenia: a meta-analysis and systematic review of synaptic protein and mRNA measures. Mol Psychiatry 2019; 24:549-561. [PMID: 29511299 PMCID: PMC6004314 DOI: 10.1038/s41380-018-0041-5] [Citation(s) in RCA: 145] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 01/05/2018] [Accepted: 01/31/2018] [Indexed: 02/06/2023]
Abstract
Although synaptic loss is thought to be core to the pathophysiology of schizophrenia, the nature, consistency and magnitude of synaptic protein and mRNA changes has not been systematically appraised. Our objective was thus to systematically review and meta-analyse findings. The entire PubMed database was searched for studies from inception date to the 1st of July 2017. We selected case-control postmortem studies in schizophrenia quantifying synaptic protein or mRNA levels in brain tissue. The difference in protein and mRNA levels between cases and controls was extracted and meta-analysis conducted. Among the results, we found a significant reduction in synaptophysin in schizophrenia in the hippocampus (effect size: -0.65, p < 0.01), frontal (effect size: -0.36, p = 0.04), and cingulate cortices (effect size: -0.54, p = 0.02), but no significant changes for synaptophysin in occipital and temporal cortices, and no changes for SNAP-25, PSD-95, VAMP, and syntaxin in frontal cortex. There were insufficient studies for meta-analysis of complexins, synapsins, rab3A and synaptotagmin and mRNA measures. Findings are summarised for these, which generally show reductions in SNAP-25, PSD-95, synapsin and rab3A protein levels in the hippocampus but inconsistency in other regions. Our findings of moderate-large reductions in synaptophysin in hippocampus and frontal cortical regions, and a tendency for reductions in other pre- and postsynaptic proteins in the hippocampus are consistent with models that implicate synaptic loss in schizophrenia. However, they also identify potential differences between regions and proteins, suggesting synaptic loss is not uniform in nature or extent.
Collapse
|
9
|
Abidin İ, Aydin-Abidin S, Bodur A, İnce İ, Alver A. Brain-derived neurotropic factor (BDNF) heterozygous mice are more susceptible to synaptic protein loss in cerebral cortex during high fat diet. Arch Physiol Biochem 2018; 124:442-447. [PMID: 29277119 DOI: 10.1080/13813455.2017.1420666] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In this study we aimed to investigate whether reduced BDNF levels aggravate the susceptibility of the brain to hazardous effects of high fat diet. For this purpose, we fed BDNF heterozygous mice and wild type littermates with normal and high fat diet for 16 weeks. Concentrations of two synaptic proteins (SNAP-25 and PSD-95) and oxidative stress parameters (MDA, SOD, CAT) were evaluated in the cortex after diet period. Interestingly, body weights of BDNF heterozygous groups fed with control diet were higher than their littermates and heterozygous mice fed with HFD were the heaviest in all experimental groups. MDA levels were significantly elevated in both HFD groups (wild type and BDNF(+/-)). Synaptic markers PSD-95 and SNAP-25 markedly decreased in BDNF(+/-) group fed with HFD compared to other groups. In conclusion, we suggest that endogenous BDNF has an important and possibly protective role in diet-induced changes in the cortex.
Collapse
Affiliation(s)
- İsmail Abidin
- a Department of Biophysics, Faculty of Medicine , Karadeniz Technical University , Trabzon , Turkey
| | - Selcen Aydin-Abidin
- a Department of Biophysics, Faculty of Medicine , Karadeniz Technical University , Trabzon , Turkey
| | - Akin Bodur
- b Department of Medical Biochemistry, Faculty of Medicine , Karadeniz Technical University , Trabzon , Turkey
| | - İmran İnce
- b Department of Medical Biochemistry, Faculty of Medicine , Karadeniz Technical University , Trabzon , Turkey
| | - Ahmet Alver
- b Department of Medical Biochemistry, Faculty of Medicine , Karadeniz Technical University , Trabzon , Turkey
| |
Collapse
|
10
|
Hou HT, Wang J, Zhang X, Wang ZQ, Chen TN, Zhang JL, Yang Q, He GW. Endothelial nitric oxide synthase enhancer AVE3085 reverses endothelial dysfunction induced by homocysteine in human internal mammary arteries. Nitric Oxide 2018; 81:21-27. [PMID: 30300735 DOI: 10.1016/j.niox.2018.10.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 09/07/2018] [Accepted: 10/04/2018] [Indexed: 12/23/2022]
Abstract
Homocysteine (Hcy) is an independent risk factor for endothelial dysfunction in cardiovascular diseases. We hypothesized that the eNOS transcription enhancer AVE3085 may protect the endothelial function damaged by Hcy in the human internal mammary artery (IMA). Cumulative concentration-relaxation curves to acetylcholine (-10 to -4.5 log mol/L) or sodium nitroprusside were established in IMA from patients undergoing coronary artery surgery precontracted by U46619 (-8 log mol/L) in the absence/presence of Hcy (100 μmol/L) with/without AVE3085 (30 μmol/L) in vitro in a myograph. RT-qPCR and ELISA were used to quantify the mRNA and protein levels of eNOS. Colorimetric assay method was used to detect the production of nitric oxide (NO). Maximal relaxation was significantly attenuated by Hcy in human IMA. Co-incubation with AVE3085 protected endothelium from the impairment by Hcy and increased the production of NO. Exposure to Hcy for 24 h downregulated eNOS protein expression (P < 0.05) whereas it upregulated the expression of eNOS at mRNA levels (P < 0.05). The presence of AVE3085 in addition to Hcy significantly increased the eNOS protein (P < 0.05) and slightly decreased the mRNA level. The study for the first time revealed that in the human blood vessels (IMA) the clinically-relevant high concentration of Hcy directly causes endothelial dysfunction by downregulating eNOS protein that may be reversed by AVE3085. These findings not only provide new direction for protecting endothelium during coronary artery bypass grafting and improving long-term patency of the grafts, but also provide evidence to the use of eNOS enhancer in the patients with endothelial dysfunction in various pathological conditions.
Collapse
Affiliation(s)
- Hai-Tao Hou
- Department of Cardiovascular Surgery & Center for Basic Medical Research, TEDA International Cardiovascular Hospital, Chinese Academy of Medical Sciences, Tianjin, China; The Affiliated Hospital of Hangzhou Normal University& Zhejiang University, Hangzhou, China
| | - Jun Wang
- Department of Cardiovascular Surgery & Center for Basic Medical Research, TEDA International Cardiovascular Hospital, Chinese Academy of Medical Sciences, Tianjin, China
| | - Xi Zhang
- Department of Cardiovascular Surgery & Center for Basic Medical Research, TEDA International Cardiovascular Hospital, Chinese Academy of Medical Sciences, Tianjin, China
| | - Zheng-Qing Wang
- Department of Cardiovascular Surgery & Center for Basic Medical Research, TEDA International Cardiovascular Hospital, Chinese Academy of Medical Sciences, Tianjin, China
| | - Tie-Nan Chen
- Department of Cardiovascular Surgery & Center for Basic Medical Research, TEDA International Cardiovascular Hospital, Chinese Academy of Medical Sciences, Tianjin, China
| | - Jian-Liang Zhang
- Department of Cardiovascular Surgery & Center for Basic Medical Research, TEDA International Cardiovascular Hospital, Chinese Academy of Medical Sciences, Tianjin, China
| | - Qin Yang
- Department of Cardiovascular Surgery & Center for Basic Medical Research, TEDA International Cardiovascular Hospital, Chinese Academy of Medical Sciences, Tianjin, China
| | - Guo-Wei He
- Department of Cardiovascular Surgery & Center for Basic Medical Research, TEDA International Cardiovascular Hospital, Chinese Academy of Medical Sciences, Tianjin, China; The Affiliated Hospital of Hangzhou Normal University& Zhejiang University, Hangzhou, China; Department of Surgery, Oregon Health and Science University, Portland, OR, USA.
| |
Collapse
|
11
|
Ghumatkar P, Peshattiwar V, Patil S, Muke S, Whitfield D, Howlett D, Francis P, Sathaye S. The effect of phloretin on synaptic proteins and adult hippocampal neurogenesis in Aβ (1-42)-injected male Wistar rats. J Pharm Pharmacol 2018; 70:1022-1030. [DOI: 10.1111/jphp.12925] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 03/24/2018] [Indexed: 12/21/2022]
Abstract
Abstract
Objectives
Considering the deleterious effect of Aβ1-42, a study was designed to evaluate the effect of phloretin on altered synaptic proteins and adult hippocampal neurogenesis in Aβ1-42-injected Wistar rats.
Methods
The rats were pretreated with 5 mg/kg p.o dose of phloretin and donepezil (positive control) for 28 days, followed by intrahippocampal injections of aggregated Aβ1-42. After termination, perfused brains were isolated and subjected to Western blot and immunohistochemistry (IHC) analysis.
Key findings
The Western blot revealed that Aβ1-42-injected rats had significantly low levels of synaptophysin as compared to sham control. Phloretin pretreatment significantly protected the presynaptic protein synaptophysin against the effects of Aβ1-42. There were no significant changes in the levels of PSD95 between different groups. The IHC findings showed that Aβ1-42 significantly reduced the Ki67 and DCX in the dentate gyrus as compared to sham control. However, phloretin significantly improved the number of Ki67- and DCX-positive neurons in the dentate gyrus region as compared to Aβ1-42 group.
Conclusions
This study demonstrated the protective effect of phloretin on synaptophysin and adult neuronal proliferating cells in Aβ1-42-injected rats. The encouraging findings highlight the potential of phloretin as a dietary supplement targeting key therapeutic mechanisms in neurodegenerative disorders such as AD.
Collapse
Affiliation(s)
- Priya Ghumatkar
- Pharmacology Research Laboratory-II, Department of Pharmaceutical Sciences and Technology, Institute of Chemical Technology (University under Section 3 of UGC Act-1956, Elite Status & Centre of Excellence – Govt. of Maharashtra, TEQIP Phase II Funded), Mumbai, India
| | - Vaibhavi Peshattiwar
- Pharmacology Research Laboratory-II, Department of Pharmaceutical Sciences and Technology, Institute of Chemical Technology (University under Section 3 of UGC Act-1956, Elite Status & Centre of Excellence – Govt. of Maharashtra, TEQIP Phase II Funded), Mumbai, India
| | - Sachin Patil
- Pharmacology Research Laboratory-II, Department of Pharmaceutical Sciences and Technology, Institute of Chemical Technology (University under Section 3 of UGC Act-1956, Elite Status & Centre of Excellence – Govt. of Maharashtra, TEQIP Phase II Funded), Mumbai, India
| | - Suraj Muke
- Pharmacology Research Laboratory-II, Department of Pharmaceutical Sciences and Technology, Institute of Chemical Technology (University under Section 3 of UGC Act-1956, Elite Status & Centre of Excellence – Govt. of Maharashtra, TEQIP Phase II Funded), Mumbai, India
| | - David Whitfield
- Wolfson Centre for Age-Related Diseases, King's College London, London, UK
| | - David Howlett
- Wolfson Centre for Age-Related Diseases, King's College London, London, UK
| | - Paul Francis
- Wolfson Centre for Age-Related Diseases, King's College London, London, UK
| | - Sadhana Sathaye
- Pharmacology Research Laboratory-II, Department of Pharmaceutical Sciences and Technology, Institute of Chemical Technology (University under Section 3 of UGC Act-1956, Elite Status & Centre of Excellence – Govt. of Maharashtra, TEQIP Phase II Funded), Mumbai, India
| |
Collapse
|
12
|
A Presynaptic Group III mGluR Recruits Gβγ/SNARE Interactions to Inhibit Synaptic Transmission by Cone Photoreceptors in the Vertebrate Retina. J Neurosci 2017; 37:4618-4634. [PMID: 28363980 DOI: 10.1523/jneurosci.2948-16.2017] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 03/27/2017] [Accepted: 03/28/2017] [Indexed: 11/21/2022] Open
Abstract
G-protein βγ subunits (Gβγ) interact with presynaptic proteins and regulate neurotransmitter release downstream of Ca2+ influx. To accomplish their roles in sensory signaling, photoreceptor synapses use specialized presynaptic proteins that support neurotransmission at active zone structures known as ribbons. While several G-protein coupled receptors (GPCRs) influence synaptic transmission at ribbon synapses of cones and other retinal neurons, it is unknown whether Gβγ contributes to these effects. We tested whether activation of one particular GPCR, a metabotropic glutamate receptor (mGluR), can reduce cone synaptic transmission via Gβγ in tiger salamander retinas. In recordings from horizontal cells, we found that an mGluR agonist (L-AP4) reduced cone-driven light responses and mEPSC frequency. In paired recordings of cones and horizontal cells, L-AP4 slightly reduced cone ICa (∼10%) and caused a larger reduction in cone-driven EPSCs (∼30%). Proximity ligation assay revealed direct interactions between SNAP-25 and Gβγ subunits in retinal synaptic layers. Pretreatment with the SNAP-25 cleaving protease BoNT/A inhibited L-AP4 effects on synaptic transmission, as did introduction of a peptide derived from the SNAP-25 C terminus. Introducing Gβγ subunits directly into cones reduced EPSC amplitude. This effect was inhibited by BoNT/A, supporting a role for Gβγ/SNAP-25 interactions. However, the mGluR-dependent reduction in ICa was not mimicked by Gβγ, indicating that this effect was independent of Gβγ. The finding that synaptic transmission at cone ribbon synapses is regulated by Gβγ/SNAP-25 interactions indicates that these mechanisms are shared by conventional and ribbon-type synapses. Gβγ liberated from other photoreceptor GPCRs is also likely to regulate synaptic transmission.SIGNIFICANCE STATEMENT Dynamic regulation of synaptic transmission by presynaptic G-protein coupled receptors shapes information flow through neural circuits. At the first synapse in the visual system, presynaptic metabotropic glutamate receptors (mGluRs) regulate cone photoreceptor synaptic transmission, although the mechanisms and functional impact of this are unclear. We show that mGluRs regulate light response encoding across the cone synapse, accomplished in part by triggering G-protein βγ subunits (Gβγ) interactions with SNAP-25, a core component of the synaptic vesicle fusion machinery. In addition to revealing a role in visual processing, this provides the first demonstration that Gβγ/SNAP-25 interactions regulate synaptic function at a ribbon-type synapse, contributing to an emerging picture of the ubiquity of Gβγ/SNARE interactions in regulating synaptic transmission throughout the nervous system.
Collapse
|
13
|
Synaptic proteins predict cognitive decline in Alzheimer's disease and Lewy body dementia. Alzheimers Dement 2016; 12:1149-1158. [DOI: 10.1016/j.jalz.2016.04.005] [Citation(s) in RCA: 100] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2015] [Revised: 04/01/2016] [Accepted: 04/13/2016] [Indexed: 11/21/2022]
|
14
|
Hou HT, Wang J, Wang ZQ, Liu XC, Marinko M, Novakovic A, Yang Q, He GW. Effect of Benidipine in Human Internal Mammary Artery and Clinical Implications. Ann Thorac Surg 2016; 101:1789-95. [DOI: 10.1016/j.athoracsur.2015.10.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 09/08/2015] [Accepted: 10/12/2015] [Indexed: 01/18/2023]
|
15
|
Tratnjek L, Glavan G, Višnjar T, Živin M. Upregulation and axonal transport of synaptotagmin-IV in the direct-pathway medium spiny neurons in hemi-parkinsonian rats induced by dopamine D1 receptor stimulation. Eur J Neurosci 2016; 43:885-98. [PMID: 26750488 DOI: 10.1111/ejn.13161] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 12/05/2015] [Accepted: 12/26/2015] [Indexed: 01/06/2023]
Abstract
Synaptotagmin-IV (Syt-IV) may function as a regulator of Ca(2+) -dependent synaptic transmission. In the hemi-parkinsonian rats with unilateral lesions of dopaminergic nigrostriatal neurons Syt-IV and substance-P (SP) mRNAs could be upregulated within the dopaminergically hypersensitive striatum of the lesioned brain hemisphere via the stimulation of striatal dopamine D1 (D1-R), but not D2 receptors. The hypersensitive D1-R-mediated transmission may be the culprit for the undesired expression of levodopa-induced dyskinesia, implying the involvement of Syt-IV and SP in the process. First, striatal cellular phenotypes expressing Syt-IV were determined. It was found to be expressed in all striatal neurons and a small population of astrocytes. Then it was examined, if the D1-R-mediated upregulation of Syt-IV mRNA may result in the upregulation of the translated protein. It was found that, after acute stimulation with a selective D1 agonist, (±)-6-chloro-7,8-dihydroxy-3-allyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine hydrobromide (SKF-82958), Syt-IV was elevated within the SP-expressing striatal neurons of the lesioned side. This was followed by the upregulation of Syt-IV, but not of its mRNA, within the ipsilateral target nuclei of the direct-pathway medium spiny neurons, indicating axonal transport of de novo synthesized protein to their SP-positive synaptic terminals. However, despite the striatal upregulation of SP and Syt-IV following a similar time-course, their subcellular co-localization within the axonal terminals was not found. It was therefore suggested that Syt-IV may regulate the hypersensitive striatal synaptic transmission, although via a SP-independent mechanism.
Collapse
Affiliation(s)
- Larisa Tratnjek
- Brain Research Laboratory, Medical Faculty, Institute of Pathophysiology, University of Ljubljana, Zaloška 4, 1000, Ljubljana, Slovenia
| | - Gordana Glavan
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Tanja Višnjar
- Institute of Cell Biology, Medical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Marko Živin
- Brain Research Laboratory, Medical Faculty, Institute of Pathophysiology, University of Ljubljana, Zaloška 4, 1000, Ljubljana, Slovenia
| |
Collapse
|
16
|
Experience Modulates the Effects of Histone Deacetylase Inhibitors on Gene and Protein Expression in the Hippocampus: Impaired Plasticity in Aging. J Neurosci 2015; 35:11729-42. [PMID: 26290249 DOI: 10.1523/jneurosci.4339-14.2015] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
UNLABELLED The therapeutic potential of histone deacetylase inhibitor (HDACi) treatment has attracted considerable attention in the emerging area of cognitive neuroepigenetics. The possibility that ongoing cognitive experience importantly regulates the cell biological effects of HDACi administration, however, has not been systematically examined. In an initial experiment addressing this issue, we tested whether water maze training influences the gene expression response to acute systemic HDACi administration in the young adult rat hippocampus. Training powerfully modulated the response to HDACi treatment, increasing the total number of genes regulated to nearly 3000, including many not typically linked to neural plasticity, compared with <300 following HDACi administration alone. Although water maze training itself also regulated nearly 1800 genes, the specific mRNAs, gene networks, and biological pathways involved were largely distinct when the same experience was provided together with HDACi administration. Next, we tested whether the synaptic protein response to HDACi treatment is similarly dependent on recent cognitive experience, and whether this plasticity is altered in aged rats with memory impairment. Whereas synaptic protein labeling in the young hippocampus was selectively increased when HDACi administration was provided in conjunction with water maze training, combined treatment had no effect on synaptic proteins in the aged hippocampus. Our findings indicate that ongoing experience potently regulates the molecular consequences of HDACi treatment and that the interaction of recent cognitive experience with histone acetylation dynamics is disrupted in the aged hippocampus. SIGNIFICANCE STATEMENT The possibility that interventions targeting epigenetic regulation could be effective in treating a range of neurodegenerative disorders has attracted considerable interest. Here we demonstrate in the rat hippocampus that ongoing experience powerfully modifies the molecular response to one such intervention, histone deacetylase inhibitor (HDACi) administration. A single learning episode dramatically shifts the gene expression profile induced by acute HDACi treatment, yielding a qualitatively distinct hippocampal transcriptome compared with the influence of behavioral training alone. The downstream synaptic protein response to HDACi administration is similarly experience-dependent, and we report that this plasticity is disrupted in the aged hippocampus. The findings highlight that accommodating the modulatory influence of ongoing experience represents a challenge for therapeutic development in the area of cognitive neuroepigenetics.
Collapse
|
17
|
Lee I, Eriksson P, Fredriksson A, Buratovic S, Viberg H. Developmental neurotoxic effects of two pesticides: Behavior and neuroprotein studies on endosulfan and cypermethrin. Toxicology 2015; 335:1-10. [DOI: 10.1016/j.tox.2015.06.010] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 06/25/2015] [Accepted: 06/29/2015] [Indexed: 01/27/2023]
|
18
|
Gottschall PE, Howell MD. ADAMTS expression and function in central nervous system injury and disorders. Matrix Biol 2015; 44-46:70-6. [PMID: 25622912 PMCID: PMC5068130 DOI: 10.1016/j.matbio.2015.01.014] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Revised: 01/19/2015] [Accepted: 01/19/2015] [Indexed: 11/21/2022]
Abstract
The components of the adult extracellular matrix in the central nervous system form a lattice-like structure that is deposited as perineuronal nets, around axon initial segments and as synapse-associated matrix. An abundant component of this matrix is the lecticans, chondroitin sulfate-bearing proteoglycans that are the major substrate for several members of the ADAMTSs (a disintegrin and metalloproteinase with thrombospondin motifs) family. Since lecticans are key regulators of neural plasticity, ADAMTS cleavage of lecticans would likely also contribute to neuroplasticity. Indeed, many studies have examined the neuroplastic contribution of the ADAMTSs to damage and recovery after injury and in central nervous system disease. Much of this data supports a role for the ADAMTSs in recovery and repair following spinal cord injury by stimulating axonal outgrowth after degradation of a glial scar and improving synaptic plasticity following seizure-induced neural damage in the brain. The action of the ADAMTSs in chronic diseases of the central nervous system appears to be more complex and less well-defined. Increasing evidence indicates that lecticans participate in synaptic plasticity in neurodegenerative disease states. It will be interesting to examine how ADAMTS expression and action would affect the progression of these diseases.
Collapse
Affiliation(s)
- Paul E Gottschall
- Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States.
| | - Matthew D Howell
- Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, United States
| |
Collapse
|
19
|
Harrill JA, Chen H, Streifel KM, Yang D, Mundy WR, Lein PJ. Ontogeny of biochemical, morphological and functional parameters of synaptogenesis in primary cultures of rat hippocampal and cortical neurons. Mol Brain 2015; 8:10. [PMID: 25757474 PMCID: PMC4339650 DOI: 10.1186/s13041-015-0099-9] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 01/30/2015] [Indexed: 11/23/2022] Open
Abstract
Background Synaptogenesis is a critical neurodevelopmental process whereby pre- and postsynaptic neurons form apposed sites of contact specialized for chemical neurotransmission. Many neurodevelopmental disorders are thought to reflect altered patterns of synaptic connectivity, including imbalances between excitatory and inhibitory synapses. Developing rapid throughput approaches for assessing synaptogenesis will facilitate toxicologic and drug screening studies of neurodevelopmental disorders. The current study describes the use of high-content imaging to quantify the ontogeny of excitatory and inhibitory synapses using in vitro models of neurodevelopment. These data are compared to biochemical and functional measures of synaptogenesis. Results The ontogenetic patterns of synapse formation were compared between primary rodent hippocampal and cortical neurons over 28 days in vitro (DIV). As determined by ELISA, the increase in synaptophysin expression levels as cultures matured was similar between hippocampal and cortical cultures. High-content imaging of immunoreactivity of excitatory and inhibitory synaptic biomarkers demonstrated an overall greater number of synapses in hippocampal relative to cortical neurons with marked differences in the pattern of inhibitory synapse development between these two neuronal cell types. Functional assays revealed that both the mean firing rates and mean bursting rates were significantly increased in cortical cultures relative to hippocampal cultures. This difference may reflect decreased inhibitory synaptic tone in cortical versus hippocampal cultures. Conclusions These data demonstrate differences and similarities in the ontogeny of synaptogenesis between hippocampal and cortical neurons, depending on the biological level examined. Assessment of synaptophysin protein levels by ELISA showed a general increase in synapse formation in both cell types with increasing time in culture, while high-content imaging was able to delineate cell type-dependent differences in formation of excitatory versus inhibitory synapses. The functional significance of differences in the balance of excitatory to inhibitory synapses was confirmed by the assessment of network activity using microelectrode arrays. These results suggest that high-content imaging and microelectrode arrays provide complementary approaches for quantitative assessment of synaptogenesis, which should provide a robust readout of toxicologic and pharmacologic effects on this critical neurodevelopmental event.
Collapse
|
20
|
Howell MD, Torres-Collado AX, Iruela-Arispe ML, Gottschall PE. Selective decline of synaptic protein levels in the frontal cortex of female mice deficient in the extracellular metalloproteinase ADAMTS1. PLoS One 2012; 7:e47226. [PMID: 23071766 PMCID: PMC3469530 DOI: 10.1371/journal.pone.0047226] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Accepted: 09/12/2012] [Indexed: 11/24/2022] Open
Abstract
The chondroitin sulfate-bearing proteoglycans, also known as lecticans, are a major component of the extracellular matrix (ECM) in the central nervous system and regulate neural plasticity. Growing evidence indicates that endogenous, extracellular metalloproteinases that cleave lecticans mediate neural plasticity by altering the structure of ECM aggregates. The bulk of this in vivo data examined the matrix metalloproteinases, but another metalloproteinase family that cleaves lecticans, a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS), modulates structural plasticity in vitro, although few in vivo studies have tested this concept. Thus, the purpose of this study was to examine the neurological phenotype of a mouse deficient in ADAMTS1. Adamts1 mRNA was absent in the ADAMTS1 null mouse frontal cortex, but there was no change in the abundance or proteolytic processing of the prominent lecticans brevican and versican V2. However, there was a marked increase in the perinatal lectican neurocan in juvenile ADAMTS1 null female frontal cortex. More prominently, there were declines in synaptic protein levels in the ADAMTS1 null female, but not male, frontal cortex beginning at postnatal day 28. These synaptic marker declines did not affect learning or memory in the adult female ADAMTS1 null mice when tested with the radial-arm water maze. These results indicate that in vivo Adamts1 knockout leads to sexual dimorphism in frontal cortex synaptic protein levels. Since changes in lectican abundance and proteolytic processing did not accompany the synaptic protein declines, ADAMTS1 may play a nonproteolytic role in regulating neural plasticity.
Collapse
Affiliation(s)
- Matthew D. Howell
- University of Arkansas for Medical Sciences, Department of Pharmacology and Toxicology, Little Rock, Arkansas, United States of America
| | - Antoni X. Torres-Collado
- University of California, Los Angeles, Department of Molecular, Cell, and Developmental Biology, Los Angeles, California, United States of America
| | - M. Luisa Iruela-Arispe
- University of California, Los Angeles, Department of Molecular, Cell, and Developmental Biology, Los Angeles, California, United States of America
| | - Paul E. Gottschall
- University of Arkansas for Medical Sciences, Department of Pharmacology and Toxicology, Little Rock, Arkansas, United States of America
- * E-mail:
| |
Collapse
|
21
|
Altered synaptic marker abundance in the hippocampal stratum oriens of Ts65Dn mice is associated with exuberant expression of versican. ASN Neuro 2012; 4:AN20110037. [PMID: 22225533 PMCID: PMC3275338 DOI: 10.1042/an20110037] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
DS (Down syndrome), resulting from trisomy of chromosome 21, is the most common cause of genetic mental retardation; however, the molecular mechanisms underlying the cognitive deficits are poorly understood. Growing data indicate that changes in abundance or type of CSPGs (chondroitin sulfate proteoglycans) in the ECM (extracellular matrix) can influence synaptic structure and plasticity. The purpose of this study was to identify changes in synaptic structure in the hippocampus in a model of DS, the Ts65Dn mouse, and to determine the relationship to proteoglycan abundance and/or cleavage and cognitive disability. We measured synaptic proteins by ELISA and changes in lectican expression and processing in the hippocampus of young and old Ts65Dn mice and LMCs (littermate controls). In young (5 months old) Ts65Dn hippocampal extracts, we found a significant increase in the postsynaptic protein PSD-95 (postsynaptic density 95) compared with LMCs. In aged (20 months old) Ts65Dn hippocampus, this increase was localized to hippocampal stratum oriens extracts compared with LMCs. Aged Ts65Dn mice exhibited impaired hippocampal-dependent spatial learning and memory in the RAWM (radial-arm water maze) and a marked increase in levels of the lectican versican V2 in stratum oriens that correlated with the number of errors made in the final RAWM block. Ts65Dn stratum oriens PNNs (perineuronal nets), an extension of the ECM enveloping mostly inhibitory interneurons, were dispersed over a larger area compared with LMC mice. Taken together, these data suggest a possible association with alterations in the ECM and inhibitory neurotransmission in the Ts65Dn hippocampus which could contribute to cognitive deficits.
Collapse
|
22
|
Hyperinsulinemia increases placenta endothelin-converting enzyme-1 expression in trophoblasts. Am J Hypertens 2012; 25:109-14. [PMID: 21918573 DOI: 10.1038/ajh.2011.164] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Exogenous hyperisulinemia causes pregnancy, induced hypertension and intrauterine growth restriction (IUGR) in pregnant rats. Hyperinsulinemia may increase production of endothelin-1 (ET-1), produced by sequential proteolysis of the big endothelin by the endothelin-converting enzyme (ECE)-1, the expression of which is examined here in the placenta, kidney, heart, and liver. METHODS Rats were rendered hyperinsulinemic by subcutaneous insulin pellet, mated and followed to the twenty-first day of pregnancy. They were then killed, and their fetuses and placentas were examined. RESULTS Hyperinsulinemic dams (HD) had higher blood pressure (BP) (130 ± 17 mm Hg in HD vs. 115 ± 16 mm Hg in normal pregnant dams (NPD), P < 0.05), lower placenta weight (0.44 ± 0.08 g in HD vs. 0.47 ± 0.08 NPD, P < 0.05) and lower fetus weight: males 4.9 ± 0.4 g in HD vs. 5.5 ± 0.4 g in NPD, P < 0.0001; females 4.7 ± 0.4 g in HD vs. 5.2 ± 0.4 g in NPD (P < 0.0001). ECE-1 expression as determined by western blot was significantly increased in the placenta and its implantation site, i.e., the mesometrial triangle (MT) of HD by 46 and 48%, respectively. In the kidney and heart of HD ECE-1, protein expression was increased by 230 and 220%, respectively, but its level in the liver was similar in both groups. Immunohistochemical staining revealed ECE-1 expression in endothelial cells and trophoblastic cells of the placenta and MT. Endothelin receptor A (ET-A), a mediator of vasoconstriction by ET-1, was also expressed in the endothelium and in trophoblasts of the placenta and MT. The expression of both ECE-1 and ET-A, as measured by automated image analysis, was generally stronger in placentas of HD. CONCLUSIONS ECE-1 and ET-A are expressed in the trophoblastic cells of the placenta and MT. This may affect local endothelin levels, BP and IUGR.
Collapse
|