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Zhang W, Zhu F, Zhu J, Liu K. Phospholipase D, a Novel Therapeutic Target Contributes to the Pathogenesis of Neurodegenerative and Neuroimmune Diseases. Anal Cell Pathol (Amst) 2024; 2024:6681911. [PMID: 38487684 PMCID: PMC10940030 DOI: 10.1155/2024/6681911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Revised: 01/10/2024] [Accepted: 02/14/2024] [Indexed: 03/17/2024] Open
Abstract
Phospholipase D (PLD) is an enzyme that consists of six isoforms (PLD1-PLD6) and has been discovered in different organisms including bacteria, viruses, plants, and mammals. PLD is involved in regulating a wide range of nerve cells' physiological processes, such as cytoskeleton modulation, proliferation/growth, vesicle trafficking, morphogenesis, and development. Simultaneously, PLD, which also plays an essential role in the pathogenesis of neurodegenerative and neuroimmune diseases. In this review, family members, characterizations, structure, functions and related signaling pathways, and therapeutic values of PLD was summarized, then five representative diseases including Alzheimer disease (AD), Parkinson's disease (PD), etc. were selected as examples to tell the involvement of PLD in these neurological diseases. Notably, recent advances in the development of tools for studying PLD therapy envisaged novel therapeutic interventions. Furthermore, the limitations of PLD based therapy were also analyzed and discussed. The content of this review provided a thorough and reasonable basis for further studies to exploit the potential of PLD in the treatment of neurodegenerative and neuroimmune diseases.
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Affiliation(s)
- Weiwei Zhang
- Neuroscience Center, Department of Neurology, The First Hospital of Jilin University, Changchun, China
| | - Feiqi Zhu
- Cognitive Impairment Ward of Neurology Department, The Third Affiliated Hospital of Shenzhen University Medical College, Shenzhen, China
| | - Jie Zhu
- Neuroscience Center, Department of Neurology, The First Hospital of Jilin University, Changchun, China
- Department of Neurobiology, Care Sciences and Society, Karolinska Institute, Karolinska University Hospital Solna, Stockholm, Sweden
| | - Kangding Liu
- Neuroscience Center, Department of Neurology, The First Hospital of Jilin University, Changchun, China
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Chum PP, Bishara MA, Solis SR, Behringer EJ. Cerebrovascular miRNAs Track Early Development of Alzheimer's Disease and Target Molecular Markers of Angiogenesis and Blood Flow Regulation. J Alzheimers Dis 2024; 99:S187-S234. [PMID: 37458037 PMCID: PMC10787821 DOI: 10.3233/jad-230300] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/18/2023]
Abstract
Background Alzheimer's disease (AD) is associated with impaired cerebral circulation which underscores diminished delivery of blood oxygen and nutrients to and throughout the brain. In the 3xTg-AD mouse model, we have recently found that > 10 cerebrovascular miRNAs pertaining to vascular permeability, angiogenesis, and inflammation (e.g., let-7d, miR-99a, miR-132, miR-133a, miR-151-5p, and miR-181a) track early development of AD. Further, endothelial-specific miRNAs (miR-126-3p, miR-23a/b, miR-27a) alter with onset of overall AD pathology relative to stability of smooth muscle/pericyte-specific miRNAs (miR-143, miR-145). Objective We tested the hypothesis that cerebrovascular miRNAs indicating AD pathology share mRNA targets that regulate key endothelial cell functions such as angiogenesis, vascular permeability, and blood flow regulation. Methods As detected by NanoString nCounter miRNA Expression panel for 3xTg-AD mice, 61 cerebrovascular miRNAs and respective mRNA targets were examined using Ingenuity Pathway Analysis for canonical Cardiovascular (Cardio) and Nervous System (Neuro) Signaling. Results The number of targets regulated per miRNA were 21±2 and 33±3 for the Cardio and Neuro pathways respectively, whereby 14±2 targets overlap among pathways. Endothelial miRNAs primarily target members of the PDE, PDGF, SMAD, and VEGF families. Individual candidates regulated by≥4 miRNAs that best mark AD pathology presence in 3xTg-AD mice include CFL2, GRIN2B, PDGFB, SLC6A1, SMAD3, SYT3, and TNFRSF11B. Conclusion miRNAs selective for regulation of endothelial function and respective downstream mRNA targets support a molecular basis for dysregulated cerebral blood flow regulation coupled with enhanced cell growth, proliferation, and inflammation.
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Affiliation(s)
- Phoebe P. Chum
- Basic Sciences, Loma Linda University, Loma Linda, CA, USA
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Phospholipase D1 Attenuation Therapeutics Promotes Resilience against Synaptotoxicity in 12-Month-Old 3xTg-AD Mouse Model of Progressive Neurodegeneration. Int J Mol Sci 2023; 24:ijms24043372. [PMID: 36834781 PMCID: PMC9967100 DOI: 10.3390/ijms24043372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 02/02/2023] [Accepted: 02/03/2023] [Indexed: 02/11/2023] Open
Abstract
Abrogating synaptotoxicity in age-related neurodegenerative disorders is an extremely promising area of research with significant neurotherapeutic implications in tauopathies including Alzheimer's disease (AD). Our studies using human clinical samples and mouse models demonstrated that aberrantly elevated phospholipase D1 (PLD1) is associated with amyloid beta (Aβ) and tau-driven synaptic dysfunction and underlying memory deficits. While knocking out the lipolytic PLD1 gene is not detrimental to survival across species, elevated expression is implicated in cancer, cardiovascular conditions and neuropathologies, leading to the successful development of well-tolerated mammalian PLD isoform-specific small molecule inhibitors. Here, we address the importance of PLD1 attenuation, achieved using repeated 1 mg/kg of VU0155069 (VU01) intraperitoneally every alternate day for a month in 3xTg-AD mice beginning only from ~11 months of age (with greater influence of tau-driven insults) compared to age-matched vehicle (0.9% saline)-injected siblings. A multimodal approach involving behavior, electrophysiology and biochemistry corroborate the impact of this pre-clinical therapeutic intervention. VU01 proved efficacious in preventing in later stage AD-like cognitive decline affecting perirhinal cortex-, hippocampal- and amygdala-dependent behaviors. Glutamate-dependent HFS-LTP and LFS-LTD improved. Dendritic spine morphology showed the preservation of mushroom and filamentous spine characteristics. Differential PLD1 immunofluorescence and co-localization with Aβ were noted.
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Jullienne A, Quan R, Szu JI, Trinh MV, Behringer EJ, Obenaus A. Progressive Vascular Abnormalities in the Aging 3xTg-AD Mouse Model of Alzheimer’s Disease. Biomedicines 2022; 10:biomedicines10081967. [PMID: 36009514 PMCID: PMC9405684 DOI: 10.3390/biomedicines10081967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 08/01/2022] [Accepted: 08/08/2022] [Indexed: 11/16/2022] Open
Abstract
Vascular dysfunction and structural abnormalities in Alzheimer’s disease (AD) are known to contribute to the progression of the pathology, and studies have tended to ignore the role of the vasculature in AD progression. We utilized the 3xTg-AD mouse model of AD to examine individual cerebral vessels and the cortical vascular network across the lifespan. Our vessel painting approach was used to label the entire cortical vasculature, followed by epifluorescence microscopy. The middle cerebral artery (MCA) tree was assessed with confocal microscopy, and a new method was developed to assess branching patterns as a measure of aging-related changes. We found that vascular remodeling was profoundly altered at 4–6 months of age, when the 3xTg-AD mouse is known to transition to cognitive impairment and Aβ deposition in both sexes. Analysis of vascular features (density, junctions, length) of the MCA territory highlighted sex-dependent differences across the 3xTg-AD mouse lifespan, with no alterations in branching patterns. Our current cerebrovascular angioarchitectural analyses demonstrate progressive alterations in individual cortical vessels, as well as in the vascular network of the cortex. These new findings advance our understanding of brain anatomy and physiology in the 3xTg-AD mouse, while potentially identifying unique diagnostic signatures of AD progression.
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Affiliation(s)
- Amandine Jullienne
- Department of Pediatrics, University of California, Irvine, CA 92697, USA
| | - Ryan Quan
- Department of Pediatrics, University of California, Irvine, CA 92697, USA
| | - Jenny I. Szu
- Department of Pediatrics, University of California, Irvine, CA 92697, USA
| | - Michelle V. Trinh
- Department of Pediatrics, University of California, Irvine, CA 92697, USA
| | - Erik J. Behringer
- Department of Basic Sciences, Loma Linda University, Loma Linda, CA 92350, USA
| | - Andre Obenaus
- Department of Pediatrics, University of California, Irvine, CA 92697, USA
- Department of Basic Sciences, Loma Linda University, Loma Linda, CA 92350, USA
- Correspondence:
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Barber CN, Goldschmidt HL, Lilley B, Bygrave AM, Johnson RC, Huganir RL, Zack DJ, Raben DM. Differential expression patterns of phospholipase D isoforms 1 and 2 in the mammalian brain and retina. J Lipid Res 2022; 63:100247. [PMID: 35764123 PMCID: PMC9305353 DOI: 10.1016/j.jlr.2022.100247] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 06/10/2022] [Accepted: 06/20/2022] [Indexed: 01/16/2023] Open
Abstract
Phosphatidic acid is a key signaling molecule heavily implicated in exocytosis due to its protein-binding partners and propensity to induce negative membrane curvature. One phosphatidic acid-producing enzyme, phospholipase D (PLD), has also been implicated in neurotransmission. Unfortunately, due to the unreliability of reagents, there has been confusion in the literature regarding the expression of PLD isoforms in the mammalian brain which has hampered our understanding of their functional roles in neurons. To address this, we generated epitope-tagged PLD1 and PLD2 knockin mice using CRISPR/Cas9. Using these mice, we show that PLD1 and PLD2 are both localized at synapses by adulthood, with PLD2 expression being considerably higher in glial cells and PLD1 expression predominating in neurons. Interestingly, we observed that only PLD1 is expressed in the mouse retina, where it is found in the synaptic plexiform layers. These data provide critical information regarding the localization and potential role of PLDs in the central nervous system.
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Affiliation(s)
- Casey N Barber
- Department of Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, MD, USA; Solomon H. Snyder Department of Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Hana L Goldschmidt
- Solomon H. Snyder Department of Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Brendan Lilley
- Department of Ophthalmology, Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Alexei M Bygrave
- Solomon H. Snyder Department of Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Richard C Johnson
- Solomon H. Snyder Department of Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Richard L Huganir
- Solomon H. Snyder Department of Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Donald J Zack
- Department of Ophthalmology, Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Daniel M Raben
- Department of Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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Das D, Podder S. Deregulation of ceRNA Networks in Frontal Cortex and Choroid Plexus of Brain during SARS-CoV-2 Infection Aggravates Neurological Manifestations: An Insight from Bulk and Single-Cell Transcriptomic Analyses. Adv Biol (Weinh) 2022; 6:e2101310. [PMID: 35661455 PMCID: PMC9348399 DOI: 10.1002/adbi.202101310] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 05/20/2022] [Indexed: 01/28/2023]
Abstract
Although transcriptomic studies of SARS-CoV-2-infected brains have depicted variability in gene expression, the landscape of deregulated cell-specific regulatory circuits has not been elucidated yet. Hence, bulk and single-cell RNA-seq data are analyzed to gain detailed insights. Initially, two ceRNA networks with 19 and 3 differentially expressed (DE) hub lncRNAs are reconstructed in SARS-CoV-2 infected Frontal Cortex (FC) and Choroid Plexus (CP), respectively. Functional and pathway enrichment analyses of downstream mRNAs of deregulated ceRNA axes demonstrate impairment of neurological processes. Mapping of hub lncRNA-mRNA pairs from bulk RNA-seq with snRNA-seq data has indicated that NORAD, NEAT1, and STXBP5-AS1 are downregulated across 4, 4, and 2 FC cell types, respectively. At the same time, MIRLET7BHG and MALAT1 are upregulated in excitatory neurons of FC and neurons of CP, respectively. Here, it is hypothesized that downregulation of NORAD, NEAT1, and STXBP5-AS1, and upregulation of MIRLET7BHG and MALAT1 might deregulate respectively 51, 6, and 37, and 31 and 19 mRNAs in cell types of FC and CP. Afterward, 13 therapeutic miRNAs are traced that might safeguard against deregulated lncRNA-mRNA pairs of NORAD, NEAT1, and MIRLET7BHG in FC. This study helps to explain the plausible mechanism of post-COVID neurological manifestation and also to devise therapeutics against it.
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Affiliation(s)
- Deepyaman Das
- Department of MicrobiologyRaiganj UniversityRaiganjUttar DinajpurWest Bengal733134India
| | - Soumita Podder
- Department of MicrobiologyRaiganj UniversityRaiganjUttar DinajpurWest Bengal733134India
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Marcatti M, Fracassi A, Montalbano M, Natarajan C, Krishnan B, Kayed R, Taglialatela G. Aβ/tau oligomer interplay at human synapses supports shifting therapeutic targets for Alzheimer's disease. Cell Mol Life Sci 2022; 79:222. [PMID: 35377002 PMCID: PMC8979934 DOI: 10.1007/s00018-022-04255-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Revised: 03/08/2022] [Accepted: 03/17/2022] [Indexed: 12/14/2022]
Abstract
BACKGROUND Alzheimer's disease (AD) is characterized by progressive cognitive decline due to accumulating synaptic insults by toxic oligomers of amyloid beta (AβO) and tau (TauO). There is growing consensus that preventing these oligomers from interacting with synapses might be an effective approach to treat AD. However, recent clinical trial failures suggest low effectiveness of targeting Aβ in late-stage AD. Researchers have redirected their attention toward TauO as the levels of this species increase later in disease pathogenesis. Here we show that AβO and TauO differentially target synapses and affect each other's binding dynamics. METHODS Binding of labeled, pre-formed Aβ and tau oligomers onto synaptosomes isolated from the hippocampus and frontal cortex of mouse and postmortem cognitively intact elderly human brains was evaluated using flow-cytometry and western blot analyses. Binding of labeled, pre-formed Aβ and tau oligomers onto mouse primary neurons was assessed using immunofluorescence assay. The synaptic dysfunction was measured by fluorescence analysis of single-synapse long-term potentiation (FASS-LTP) assay. RESULTS We demonstrated that higher TauO concentrations effectively outcompete AβO and become the prevailing synaptic-associated species. Conversely, high concentrations of AβO facilitate synaptic TauO recruitment. Immunofluorescence analyses of mouse primary cortical neurons confirmed differential synaptic binding dynamics of AβO and TauO. Moreover, in vivo experiments using old 3xTgAD mice ICV injected with either AβO or TauO fully supported these findings. Consistent with these observations, FASS-LTP analyses demonstrated that TauO-induced suppression of chemical LTP was exacerbated by AβO. Finally, predigestion with proteinase K abolished the ability of TauO to compete off AβO without affecting the ability of high AβO levels to increase synaptic TauO recruitment. Thus, unlike AβO, TauO effects on synaptosomes are hampered by the absence of protein substrate in the membrane. CONCLUSIONS These results introduce the concept that TauO become the main synaptotoxic species at late AD, thus supporting the hypothesis that TauO may be the most effective therapeutic target for clinically manifest AD.
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Affiliation(s)
- Michela Marcatti
- Department of Neurology, Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, TX 77555 USA
| | - Anna Fracassi
- Department of Neurology, Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, TX 77555 USA
| | - Mauro Montalbano
- Department of Neurology, Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, TX 77555 USA
| | - Chandramouli Natarajan
- Department of Neurology, Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, TX 77555 USA
| | - Balaji Krishnan
- Department of Neurology, Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, TX 77555 USA
| | - Rakez Kayed
- Department of Neurology, Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, TX 77555 USA
| | - Giulio Taglialatela
- Department of Neurology, Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, TX 77555 USA
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Chum PP, Hakim MA, Behringer EJ. Cerebrovascular microRNA Expression Profile During Early Development of Alzheimer's Disease in a Mouse Model. J Alzheimers Dis 2021; 85:91-113. [PMID: 34776451 DOI: 10.3233/jad-215223] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Emerging evidence demonstrates association of Alzheimer's disease (AD) with impaired delivery of blood oxygen and nutrients to and throughout the brain. The cerebral circulation plays multiple roles underscoring optimal brain perfusion and cognition entailing moment-to-moment blood flow control, vascular permeability, and angiogenesis. With currently no effective treatment to prevent or delay the progression of AD, cerebrovascular microRNA (miRNA) markers corresponding to post-transcriptional regulation may distinguish phases of AD. OBJECTIVE We tested the hypothesis that cerebrovascular miRNA expression profiles indicate developmental stages of AD pathology. METHODS Total RNA was isolated from total brain vessel segments of male and female 3xTg-AD mice [young, 1-2 mo; cognitive impairment (CI), 4-5 mo; extracellular amyloid-β plaques (Aβ), 6-8 mo; plaques+neurofibrillary tangles (AβT), 12-15 mo]. NanoString technology nCounter miRNA Expression panel for mouse was used to screen for 599 miRNAs. RESULTS Significant (p < 0.05) downregulation of various miRNAs indicated transitions from young to CI (e.g., let-7g & miR-1944, males; miR-133a & miR-2140, females) and CI to Aβ (e.g., miR-99a, males) but not from Aβ to AβT. In addition, altered expression of select miRNAs from overall Pre-AD (young + CI) versus AD (Aβ+ AβT) were detected in both males (let-7d, let-7i, miR-23a, miR-34b-3p, miR-99a, miR-126-3p, miR-132, miR-150, miR-151-5p, miR-181a) and females (miR-150, miR-539). Altogether, at least 20 cerebrovascular miRNAs effectively delineate AD versus Pre-AD pathology. CONCLUSION Using the 3xTg-AD mouse model, these data demonstrate that cerebrovascular miRNAs pertaining to endothelial function, vascular permeability, angiogenesis, inflammation, and Aβ/tau metabolism can track early development of AD.
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Affiliation(s)
- Phoebe P Chum
- Basic Sciences, Loma Linda University, Loma Linda, CA, USA
| | - Md A Hakim
- Basic Sciences, Loma Linda University, Loma Linda, CA, USA
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Singh A, Allen D, Fracassi A, Tumurbaatar B, Natarajan C, Scaduto P, Woltjer R, Kayed R, Limon A, Krishnan B, Taglialatela G. Functional Integrity of Synapses in the Central Nervous System of Cognitively Intact Individuals with High Alzheimer's Disease Neuropathology Is Associated with Absence of Synaptic Tau Oligomers. J Alzheimers Dis 2021; 78:1661-1678. [PMID: 33185603 PMCID: PMC7836055 DOI: 10.3233/jad-200716] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Certain individuals, here referred to as Non-Demented with Alzheimer Neuropathology (NDAN), do not show overt neurodegeneration (N-) and remain cognitively intact despite the presence of plaques (A+) and tangles (T+) that would normally be consistent with fully symptomatic Alzheimer's disease (AD). OBJECTIVE The existence of NDAN (A + T+N-) subjects suggests that the human brain utilizes intrinsic mechanisms that can naturally evade cognitive decline normally associated with the symptomatic stages of AD (A + T+N+). Deciphering the underlying mechanisms would prove relevant to develop complementing therapeutics to prevent progression of AD-related cognitive decline. METHODS Previously, we have reported that NDAN present with preserved neurogenesis and synaptic integrity paralleled by absence of amyloid oligomers at synapses. Using postmortem brain samples from age-matched control subjects, demented AD patients and NDAN individuals, we performed immunofluorescence, western blots, micro transplantation of synaptic membranes in Xenopus oocytes followed by twin electrode voltage clamp electrophysiology and fluorescence assisted single synaptosome-long term potentiation studies. RESULTS We report decreased tau oligomers at synapses in the brains of NDAN subjects. Furthermore, using novel approaches we report, for the first time, that such absence of tau oligomers at synapses is associated with synaptic functional integrity in NDAN subjects as compared to demented AD patients. CONCLUSION Overall, these results give further credence to tau oligomers as primary actors of synaptic destruction underscoring cognitive demise in AD and support their targeting as a viable therapeutic strategy for AD and related tauopathies.
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Affiliation(s)
- Ayush Singh
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, UTMB Galveston, TX, USA
| | - Dyron Allen
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, UTMB Galveston, TX, USA
| | - Anna Fracassi
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, UTMB Galveston, TX, USA
| | - Batbayar Tumurbaatar
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, UTMB Galveston, TX, USA
| | - Chandramouli Natarajan
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, UTMB Galveston, TX, USA
| | - Pietro Scaduto
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, UTMB Galveston, TX, USA
| | - Randy Woltjer
- Department of Pathology, Oregon Health and Science University, Portland, OR, USA
| | - Rakez Kayed
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, UTMB Galveston, TX, USA
| | - Agenor Limon
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, UTMB Galveston, TX, USA
| | - Balaji Krishnan
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, UTMB Galveston, TX, USA,Correspondence to: Giulio Taglialatela, PhD, Mitchell Center for Neurodegenerative Diseases, Department of Neurology, UTMB Galveston, TX, USA. Tel.: +1 409 772 1679; Fax: +1 409 772 0015; E-mail: . and Balaji Krishnan, PhD, Mitchell Center for Neurodegenerative Diseases, Department of Neurology, UTMB Galveston, TX, USA. Tel.: +1 409 772 8069; Fax: +1 409 772 0015; E-mail:
| | - Giulio Taglialatela
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, UTMB Galveston, TX, USA,Correspondence to: Giulio Taglialatela, PhD, Mitchell Center for Neurodegenerative Diseases, Department of Neurology, UTMB Galveston, TX, USA. Tel.: +1 409 772 1679; Fax: +1 409 772 0015; E-mail: . and Balaji Krishnan, PhD, Mitchell Center for Neurodegenerative Diseases, Department of Neurology, UTMB Galveston, TX, USA. Tel.: +1 409 772 8069; Fax: +1 409 772 0015; E-mail:
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Hakim MA, Behringer EJ. Development of Alzheimer's Disease Progressively Alters Sex-Dependent KCa and Sex-Independent KIR Channel Function in Cerebrovascular Endothelium. J Alzheimers Dis 2021; 76:1423-1442. [PMID: 32651315 DOI: 10.3233/jad-200085] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Development of Alzheimer's disease (AD) pathology is associated with impaired blood flow delivery of oxygen and nutrients throughout the brain. Cerebrovascular endothelium regulates vasoreactivity of blood vessel networks for optimal cerebral blood flow. OBJECTIVE We tested the hypothesis that cerebrovascular endothelial Gq-protein-coupled receptor (GPCR; purinergic and muscarinic) and K+ channel [Ca2+-activated (KCa2.3/SK3 and KCa3.1/IK1) and inward-rectifying (KIR2.x)] function declines during progressive AD pathology. METHODS We applied simultaneous measurements of intracellular Ca2+ ([Ca2+]i) and membrane potential (Vm) in freshly isolated endothelium from posterior cerebral arteries of 3×Tg-AD mice [young, no pathology (1- 2 mo), cognitive impairment (CI; 4- 5 mo), extracellular Aβ plaques (Aβ; 6- 8 mo), and Aβ plaques + neurofibrillary tangles (AβT; 12- 15 mo)]. RESULTS The coupling of ΔVm-to-Δ[Ca2+]i during AβT pathology was lowest for both sexes but, overall, ATP-induced purinergic receptor function was stable throughout AD pathology. SKCa/IKCa channel function itself was enhanced by ∼20% during AD (Aβ+ AβT) versus pre-AD (Young + CI) in males while steady in females. Accordingly, hyperpolarization-induced [Ca2+]i increases following SKCa/IKCa channel activation and Δ[Ca2+]i-to-ΔVm coupling was enhanced by ≥two-fold during AD pathology in males but not females. Further, KIR channel function decreased by ∼50% during AD conditions versus young regardless of sex. Finally, other than a ∼40% increase in females versus males during Aβ pathology, [Ca2+]i responses to the mitochondrial uncoupler FCCP were similar among AD versus pre-AD conditions. CONCLUSION Altogether, AD pathology represents a condition of altered KCa and KIR channel function in cerebrovascular endothelium in a sex-dependent and sex-independent manner respectively.
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Affiliation(s)
- Md A Hakim
- Basic Sciences, Loma Linda University, Loma Linda, CA, USA
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11
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Chemical Stimulation of Rodent and Human Cortical Synaptosomes: Implications in Neurodegeneration. Cells 2021; 10:cells10051174. [PMID: 34065927 PMCID: PMC8151714 DOI: 10.3390/cells10051174] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 04/29/2021] [Accepted: 05/09/2021] [Indexed: 12/14/2022] Open
Abstract
Synaptic plasticity events, including long-term potentiation (LTP), are often regarded as correlates of brain functions of memory and cognition. One of the central players in these plasticity-related phenomena is the α-amino-3-hydroxy-5-methylisoxazole-4-propionate receptor (AMPAR). Increased levels of AMPARs on postsynaptic membranes thus constitute a biochemical measure of LTP. Isolated synaptic terminals (synaptosomes) are an excellent ex vivo tool to monitor synaptic physiology in healthy and diseased brains, particularly in human research. We herein describe three protocols for chemically-induced LTP (cLTP) in synaptosomes from both rodent and human brain tissues. Two of these chemical stimulation protocols are described for the first time in synaptosomes. A pharmacological block of synaptosomal actin dynamics confirmed the efficiency of the cLTP protocols. Furthermore, the study prototypically evaluated the deficiency of cLTP in cortical synaptosomes obtained from human cases of early-onset Alzheimer’s disease (EOAD) and frontotemporal lobar degeneration (FLTD), as well as an animal model that mimics FLTD.
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Smith SM, Douaud G, Chen W, Hanayik T, Alfaro-Almagro F, Sharp K, Elliott LT. An expanded set of genome-wide association studies of brain imaging phenotypes in UK Biobank. Nat Neurosci 2021; 24:737-745. [PMID: 33875891 PMCID: PMC7610742 DOI: 10.1038/s41593-021-00826-4] [Citation(s) in RCA: 165] [Impact Index Per Article: 55.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 02/23/2021] [Indexed: 02/01/2023]
Abstract
UK Biobank is a major prospective epidemiological study, including multimodal brain imaging, genetics and ongoing health outcomes. Previously, we published genome-wide associations of 3,144 brain imaging-derived phenotypes, with a discovery sample of 8,428 individuals. Here we present a new open resource of genome-wide association study summary statistics, using the 2020 data release, almost tripling the discovery sample size. We now include the X chromosome and new classes of imaging-derived phenotypes (subcortical volumes and tissue contrast). Previously, we found 148 replicated clusters of associations between genetic variants and imaging phenotypes; in this study, we found 692, including 12 on the X chromosome. We describe some of the newly found associations, focusing on the X chromosome and autosomal associations involving the new classes of imaging-derived phenotypes. Our novel associations implicate, for example, pathways involved in the rare X-linked STAR (syndactyly, telecanthus and anogenital and renal malformations) syndrome, Alzheimer's disease and mitochondrial disorders.
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Affiliation(s)
- Stephen M Smith
- Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), University of Oxford, Oxford, United Kingdom
| | - Gwenaëlle Douaud
- Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), University of Oxford, Oxford, United Kingdom
| | - Winfield Chen
- Department of Statistics and Actuarial Science, Simon Fraser University, Burnaby BC, Canada
| | - Taylor Hanayik
- Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), University of Oxford, Oxford, United Kingdom
| | - Fidel Alfaro-Almagro
- Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), University of Oxford, Oxford, United Kingdom
| | | | - Lloyd T Elliott
- Department of Statistics and Actuarial Science, Simon Fraser University, Burnaby BC, Canada.
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13
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Key Disease Mechanisms Linked to Alzheimer's Disease in the Entorhinal Cortex. Int J Mol Sci 2021; 22:ijms22083915. [PMID: 33920138 PMCID: PMC8069371 DOI: 10.3390/ijms22083915] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 04/05/2021] [Accepted: 04/07/2021] [Indexed: 02/06/2023] Open
Abstract
Alzheimer’s disease (AD) is a chronic, neurodegenerative brain disorder affecting millions of Americans that is expected to increase in incidence with the expanding aging population. Symptomatic AD patients show cognitive decline and often develop neuropsychiatric symptoms due to the accumulation of insoluble proteins that produce plaques and tangles seen in the brain at autopsy. Unexpectedly, some clinically normal individuals also show AD pathology in the brain at autopsy (asymptomatic AD, AsymAD). In this study, SWItchMiner software was used to identify key switch genes in the brain’s entorhinal cortex that lead to the development of AD or disease resilience. Seventy-two switch genes were identified that are differentially expressed in AD patients compared to healthy controls. These genes are involved in inflammation, platelet activation, and phospholipase D and estrogen signaling. Peroxisome proliferator-activated receptor γ (PPARG), zinc-finger transcription factor (YY1), sterol regulatory element-binding transcription factor 2 (SREBF2), and early growth response 1 (EGR1) were identified as transcription factors that potentially regulate switch genes in AD. Comparing AD patients to AsymAD individuals revealed 51 switch genes; PPARG as a potential regulator of these genes, and platelet activation and phospholipase D as critical signaling pathways. Chemical–protein interaction analysis revealed that valproic acid is a therapeutic agent that could prevent AD from progressing.
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14
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Chronic Low Dose Neutron Exposure Results in Altered Neurotransmission Properties of the Hippocampus-Prefrontal Cortex Axis in Both Mice and Rats. Int J Mol Sci 2021; 22:ijms22073668. [PMID: 33915974 PMCID: PMC8036585 DOI: 10.3390/ijms22073668] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 03/29/2021] [Accepted: 03/31/2021] [Indexed: 12/18/2022] Open
Abstract
The proposed deep space exploration to the moon and later to Mars will result in astronauts receiving significant chronic exposures to space radiation (SR). SR exposure results in multiple neurocognitive impairments. Recently, our cross-species (mouse/rat) studies reported impaired associative memory formation in both species following a chronic 6-month low dose exposure to a mixed field of neutrons (1 mGy/day for a total dose pf 18 cGy). In the present study, we report neutron exposure induced synaptic plasticity in the medial prefrontal cortex, accompanied by microglial activation and significant synaptic loss in the hippocampus. In a parallel study, neutron exposure was also found to alter fluorescence assisted single synaptosome LTP (FASS-LTP) in the hippocampus of rats, that may be related to a reduced ability to insert AMPAR into the post-synaptic membrane, which may arise from increased phosphorylation of the serine 845 residue of the GluA1 subunit. Thus, we demonstrate for the first time, that low dose chronic neutron irradiation impacts homeostatic synaptic plasticity in the hippocampal-cortical circuit in two rodent species, and that the ability to successfully encode associative recognition memory is a dynamic, multicircuit process, possibly involving compensatory changes in AMPAR density on the synaptic surface.
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15
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Ahmad F, Liu P. Synaptosome as a tool in Alzheimer's disease research. Brain Res 2020; 1746:147009. [PMID: 32659233 DOI: 10.1016/j.brainres.2020.147009] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 06/21/2020] [Accepted: 07/04/2020] [Indexed: 12/29/2022]
Abstract
Synapse dysfunction is an integral feature of Alzheimer's disease (AD) pathophysiology. In fact, prodromal manifestation of structural and functional deficits in synapses much prior to appearance of overt pathological hallmarks of the disease indicates that AD might be considered as a degenerative disorder of the synapses. Several research instruments and techniques have allowed us to study synaptic function and plasticity and their alterations in pathological conditions, such as AD. One such tool is the biochemically isolated preparations of detached and resealed synaptic terminals, the "synaptosomes". Because of the preservation of many of the physiological processes such as metabolic and enzymatic activities, synaptosomes have proved to be an indispensable ex vivo model system to study synapse physiology both when isolated from fresh or cryopreserved tissues, and from animal or human post-mortem tissues. This model system has been tremendously successful in the case of post-mortem tissues because of their accessibility relative to acute brain slices or cultures. The current review details the use of synaptosomes in AD research and its potential as a valuable tool in furthering our understanding of the pathogenesis and in devising and testing of therapeutic strategies for the disease.
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Affiliation(s)
- Faraz Ahmad
- Department of Anatomy, School of Biomedical Sciences, Brain Research New Zealand, University of Otago, Dunedin, New Zealand.
| | - Ping Liu
- Department of Anatomy, School of Biomedical Sciences, Brain Research New Zealand, University of Otago, Dunedin, New Zealand
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16
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Kao YC, Ho PC, Tu YK, Jou IM, Tsai KJ. Lipids and Alzheimer's Disease. Int J Mol Sci 2020; 21:ijms21041505. [PMID: 32098382 PMCID: PMC7073164 DOI: 10.3390/ijms21041505] [Citation(s) in RCA: 237] [Impact Index Per Article: 59.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 02/14/2020] [Accepted: 02/20/2020] [Indexed: 12/14/2022] Open
Abstract
Lipids, as the basic component of cell membranes, play an important role in human health as well as brain function. The brain is highly enriched in lipids, and disruption of lipid homeostasis is related to neurologic disorders as well as neurodegenerative diseases such as Alzheimer’s disease (AD). Aging is associated with changes in lipid composition. Alterations of fatty acids at the level of lipid rafts and cerebral lipid peroxidation were found in the early stage of AD. Genetic and environmental factors such as apolipoprotein and lipid transporter carrying status and dietary lipid content are associated with AD. Insight into the connection between lipids and AD is crucial to unraveling the metabolic aspects of this puzzling disease. Recent advances in lipid analytical methodology have led us to gain an in-depth understanding on lipids. As a result, lipidomics have becoming a hot topic of investigation in AD, in order to find biomarkers for disease prediction, diagnosis, and prevention, with the ultimate goal of discovering novel therapeutics.
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Affiliation(s)
- Yu-Chia Kao
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan 704, Taiwan; (Y.-C.K.); (P.-C.H.)
- Department of Pediatrics, E-DA Hospital, Kaohsiung 824, Taiwan
| | - Pei-Chuan Ho
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan 704, Taiwan; (Y.-C.K.); (P.-C.H.)
| | - Yuan-Kun Tu
- Department of Orthopedics, E-DA Hospital, Kaohsiung 824, Taiwan; (Y.-K.T.); (I.-M.J.)
| | - I-Ming Jou
- Department of Orthopedics, E-DA Hospital, Kaohsiung 824, Taiwan; (Y.-K.T.); (I.-M.J.)
| | - Kuen-Jer Tsai
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan 704, Taiwan; (Y.-C.K.); (P.-C.H.)
- Research Center of Clinical Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 704, Taiwan
- Correspondence: ; Tel.: +886-6-235-3535-4254; Fax: +886-6-275-8781
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17
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Krishnan B, Sallam HS, Tumurbataar B, Saieva S, Baymon D, Tuvdendorj D, Micci MA, Abate N, Taglialatela G. Amelioration of hippocampal dysfunction by adipose tissue-targeted stem cell transplantation in a mouse model of type 2 diabetes. J Neurochem 2020; 153:51-62. [PMID: 31730234 DOI: 10.1111/jnc.14915] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 11/01/2019] [Accepted: 11/08/2019] [Indexed: 01/01/2023]
Abstract
There is growing evidence that type 2 diabetes or insulin resistance is linked to cognitive impairment. We recently confirmed altered lipid composition, down-regulation of insulin receptor expression and impaired basal synaptic transmission in the hippocampus of our transgenic murine model of adipocyte insulin resistance (AtENPP1-Tg). Here we evaluated whether the correction of adipose tissue dysfunction [via the subcutaneous transplantation of mesenchymal stem cells (MSC)] can improve the hippocampal synaptic transmission in AtENPP1-Tg mice versus their wildtype littermates. Animals were simply randomized to receive MSC, then weighed weekly for 12 weeks. At euthanasia, we assessed leptin in the collected serum and hippocampal synaptic high-frequency stimulation long-term potentiation (HFS-LTP) using brain slices. MSC transplantation normalized AtENPP1-Tg body and epididymal fat weights and was associated with increased leptin levels, a sign of adipocyte maturation. More importantly, transplantation restored the deficiency observed in AtENPP1-Tg HFS-LTP, the cellular readout of memory. Our results further corroborate the role of adipocyte maturation arrest in adipose tissue and highlight a role for the adipose tissue in modulating hippocampal cellular mechanisms. Further studies are warranted to explore the mechanisms for the MSC-induced improvement of hippocampal HFS-LTP.
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Affiliation(s)
- Balaji Krishnan
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, TX, USA
| | - Hanaa S Sallam
- Department of Internal Medicine, Division of Endocrinology, University of Texas Medical Branch, Galveston, TX, USA.,Department of Physiology, Faculty of Medicine, Suez Canal University, Ismailia, Egypt
| | - Batbayar Tumurbataar
- Department of Internal Medicine, Division of Endocrinology, University of Texas Medical Branch, Galveston, TX, USA
| | - Salvatore Saieva
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, TX, USA.,Department of Internal Medicine, Division of Endocrinology, University of Texas Medical Branch, Galveston, TX, USA
| | - Da'Marcus Baymon
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, TX, USA
| | - Demidmaa Tuvdendorj
- Department of Internal Medicine, Division of Endocrinology, University of Texas Medical Branch, Galveston, TX, USA
| | - Maria-Adelaide Micci
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, TX, USA
| | - Nicola Abate
- Department of Internal Medicine, Division of Endocrinology, University of Texas Medical Branch, Galveston, TX, USA
| | - Giulio Taglialatela
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, TX, USA
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18
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Suppressing aberrant phospholipase D1 signaling in 3xTg Alzheimer's disease mouse model promotes synaptic resilience. Sci Rep 2019; 9:18342. [PMID: 31797996 PMCID: PMC6892889 DOI: 10.1038/s41598-019-54974-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 11/21/2019] [Indexed: 02/08/2023] Open
Abstract
Current approaches in treatment of Alzheimer's disease (AD) is focused on early stages of cognitive decline. Identifying therapeutic targets that promote synaptic resilience during early stages may prevent progressive memory deficits by preserving memory mechanisms. We recently reported that the inducible isoform of phospholipase D (PLD1) was significantly increased in synaptosomes from post-mortem AD brains compared to age-matched controls. Using mouse models, we reported that the aberrantly elevated neuronal PLD1 is key for oligomeric amyloid driven synaptic dysfunction and underlying memory deficits. Here, we demonstrate that chronic inhibition using a well-tolerated PLD1 specific small molecule inhibitor is sufficient to prevent the progression of synaptic dysfunction during early stages in the 3xTg-AD mouse model. Firstly, we report prevention of cognitive decline in the inhibitor-treated group using novel object recognition (NOR) and fear conditioning (FC). Secondly, we provide electrophysiological assessment of better synaptic function in the inhibitor-treated group. Lastly, using Golgi staining, we report that preservation of dendritic spine integrity as one of the mechanisms underlying the action of the small molecule inhibitor. Collectively, these studies provide evidence for inhibition of PLD1 as a potential therapeutic strategy in preventing progression of cognitive decline associated with AD and related dementia.
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19
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Li WQ, Luo LD, Hu ZW, Lyu TJ, Cen C, Wang Y. PLD1 promotes dendritic spine morphogenesis via activating PKD1. Mol Cell Neurosci 2019; 99:103394. [PMID: 31356881 DOI: 10.1016/j.mcn.2019.103394] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Revised: 07/24/2019] [Accepted: 07/26/2019] [Indexed: 01/20/2023] Open
Abstract
Dendritic spines on the dendrites of pyramidal neurons are one of the most important components for excitatory synapses, where excitatory information exchanges and integrates. The defects of dendritic spine development have been closely connected with many nervous system diseases including autism, intellectual disability and so forth. Based on our previous studies, we here report a new functional signaling link between phospholipase D1 (PLD1) and protein kinase D1 (PKD1) in dendritic spine morphogenesis. Coimmunoprecipitation assays showed that PLD1 associates with PKD1. A series of knocking down and rescuing experiments demonstrated that PLD1 acts upstream of PKD1 in positively regulating dendritic spine morphogenesis. Using PLD1 inhibitor, we found that PLD1 activates PKD1 to promote dendritic spine morphogenesis. Thus, we further reveal the roles of the two different enzymes in neuronal development.
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Affiliation(s)
- Wen-Qi Li
- Neuroscience Research Institute and Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory for Neuroscience, Ministry of Education, National Health Commission and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100083, China
| | - Li-Da Luo
- Neuroscience Research Institute and Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory for Neuroscience, Ministry of Education, National Health Commission and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100083, China.
| | - Zhi-Wen Hu
- Neuroscience Research Institute and Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory for Neuroscience, Ministry of Education, National Health Commission and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100083, China
| | - Tian-Jie Lyu
- Neuroscience Research Institute and Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory for Neuroscience, Ministry of Education, National Health Commission and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100083, China
| | - Cheng Cen
- Neuroscience Research Institute and Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory for Neuroscience, Ministry of Education, National Health Commission and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100083, China
| | - Yun Wang
- Neuroscience Research Institute and Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory for Neuroscience, Ministry of Education, National Health Commission and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100083, China; PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing 100871, China.
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20
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Marino C, Krishnan B, Cappello F, Taglialatela G. Hsp60 Protects against Amyloid β Oligomer Synaptic Toxicity via Modification of Toxic Oligomer Conformation. ACS Chem Neurosci 2019; 10:2858-2867. [PMID: 31091411 DOI: 10.1021/acschemneuro.9b00086] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Alzheimer's disease (AD) is the leading cause of dementia worldwide. While the etiology of AD remains uncertain, neurotoxic effects of amyloid beta oligomers (Aβo) on synaptic function, a well-established early event in AD, is an attractive area for the development of novel strategies to modify or cease the disease's progression. In this work, we tested the protective action of the mitochondrial chaperone Hsp60 against Aβo neurotoxicity, by determining the direct effect of Hsp60 in changing Aβo toxic conformations and thus reducing their dysfunctional synaptic binding and consequent suppression of long-term potentiation. Our data suggest that Hsp60 has a direct impact on Aβo, resulting in a reduction of cytotoxicity and rescue of Aβo-driven synaptic damage, thus proposing Hsp60 as an attractive therapeutic target candidate.
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Affiliation(s)
- Claudia Marino
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, Texas 77555-1045 United States
- Department of Biomedicine, Neuroscience and Advanced Diagnostics, University of Palermo, 90127 Palermo, Italy
| | - Balaji Krishnan
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, Texas 77555-1045 United States
| | - Francesco Cappello
- Department of Biomedicine, Neuroscience and Advanced Diagnostics, University of Palermo, 90127 Palermo, Italy
| | - Giulio Taglialatela
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, Texas 77555-1045 United States
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21
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Micci MA, Krishnan B, Bishop E, Zhang WR, Guptarak J, Grant A, Zolochevska O, Tumurbaatar B, Franklin W, Marino C, Widen SG, Luthra A, Kernie SG, Taglialatela G. Hippocampal stem cells promotes synaptic resistance to the dysfunctional impact of amyloid beta oligomers via secreted exosomes. Mol Neurodegener 2019; 14:25. [PMID: 31200742 PMCID: PMC6570890 DOI: 10.1186/s13024-019-0322-8] [Citation(s) in RCA: 35] [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: 10/30/2018] [Accepted: 05/03/2019] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Adult hippocampal neurogenesis plays an important role in synaptic plasticity and cogntive function. We reported that higher numbers of neural stem cells (NSC) in the hippocampus of cognitively-intact individuals with high Alzheimer's disease (AD) pathology (plaques and tangles) is associated with decreased synaptic amyloid beta oligomers (Aβο), an event linked to onset of dementia in AD. While these findings suggest a link between NSC and synaptic resistance to Aβο, the involved mechanism remains to be determined. With this goal in mind, here we investigated the ability of exosomes secreted from hippocampal NSC to promote synaptic resilience to Aβo. METHODS Exosomes isolated from media of hippocampus NSC (NSC-exo) or mature hippocampal neuronal (MN-exo) cultures were delivered intracerebroventricularly (ICV) to mice before assessment of Aβο-induced suppression of hippocampal long-term potentiation (LTP) and memory deficits. Aβο binding to synapses was assessed in cultured hippocampal neurons and on synaptosomes isolated from hippocampal slices from wild type mice and from an inducible mouse model of NSC ablation (Nestin-δ-HSV-TK mice) treated with exosomes. Expression of CaMKII and of AMPA and NMDA glutamate receptor subunits in synaptosomes was measured by western blot. Small RNA Deep sequencing was performed to identify microRNAs enriched in NSC-exo as compared to MN-exo. Mimics of select miRNAs were injected ICV. RESULTS NSC-exo, but not MN-exo, abolished Aβo-induced suppression of LTP and subsequent memory deficits. Furthermore, in hippocampal slices and cultured neurons, NSC-exo significantly decreased Aβo binding to the synapse. Similarly, transgenic ablation of endogenous NSC increased synaptic Aβo binding, which was reversed by exogenous NSC-exo. Phosphorylation of synaptic CaMKII was increased by NSC-exo, while AMPA and NMDA receptors were not affected. Lastly, we identified a set of miRNAs enriched in NSC-exo that, when injected ICV, protected the synapses from Aβo-binding and Aβo-induced LTP inhibition. CONCLUSIONS These results identify a novel mechanism linking NSC-exo and synaptic susceptibility to Aβo that may underscore cognitive resilience of certain individuals with increased neurogenesis in spite of AD neuropathology and unmask a novel target for the development of a new treatment concept for AD centered on promoting synaptic resilience to toxic amyloid proteins.
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Affiliation(s)
- Maria-Adelaide Micci
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, TX 77555 USA
| | - Balaji Krishnan
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, TX 77555 USA
| | - Elizabeth Bishop
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, TX 77555 USA
| | - Wen-Ru Zhang
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, TX 77555 USA
| | - Jutatip Guptarak
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, TX 77555 USA
| | - Auston Grant
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, TX 77555 USA
| | - Olga Zolochevska
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, TX 77555 USA
| | - Batbayar Tumurbaatar
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, TX 77555 USA
| | - Whitney Franklin
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, TX 77555 USA
| | - Claudia Marino
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, TX 77555 USA
| | - Steven G. Widen
- Biochemistry & Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555 USA
| | - Arjun Luthra
- Pressent address: The University of Texas at Austin, Austin, TX 78712 USA
| | - Steven G. Kernie
- Department of Pediatrics and Pathology & Cell Biology, Columbia University College of Physicians and Surgeons, New York, NY 10032 USA
| | - Giulio Taglialatela
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, TX 77555 USA
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22
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Franklin W, Krishnan B, Taglialatela G. Chronic synaptic insulin resistance after traumatic brain injury abolishes insulin protection from amyloid beta and tau oligomer-induced synaptic dysfunction. Sci Rep 2019; 9:8228. [PMID: 31160730 PMCID: PMC6546708 DOI: 10.1038/s41598-019-44635-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Accepted: 05/14/2019] [Indexed: 02/07/2023] Open
Abstract
Traumatic brain injury (TBI) is a risk factor for Alzheimer's disease (AD), although the mechanisms contributing to this increased risk are unknown. Insulin resistance is an additional risk factor for AD whereby decreased insulin signaling increases synaptic sensitivity to amyloid beta (Aβ) and tau. Considering this, we used rats that underwent a lateral fluid percussion injury at acute and chronic time-points to investigate whether decreased insulin responsiveness in TBI animals is playing a role in synaptic vulnerability to AD pathology. We detected acute and chronic decreases in insulin responsiveness in isolated hippocampal synaptosomes after TBI. In addition to assessing both Aβ and tau binding on synaptosomes, we performed electrophysiology to assess the dysfunctional impact of Aβ and tau oligomers as well as the protective effect of insulin. While we saw no difference in binding or degree of LTP inhibition by either Aβ or tau oligomers between sham and TBI animals, we found that insulin treatment was able to block oligomer-induced LTP inhibition in sham but not in TBI animals. Since insulin treatment has been discussed as a therapy for AD, this gives valuable insight into therapeutic implications of treating AD patients based on one's history of associated risk factors.
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Affiliation(s)
- Whitney Franklin
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, Texas, 77555, USA
- Department of Neuroscience, Cell Biology & Anatomy, University of Texas Medical Branch, Galveston, Texas, 77555, USA
| | - Balaji Krishnan
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, Texas, 77555, USA
| | - Giulio Taglialatela
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, Texas, 77555, USA.
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23
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Ondrejcak T, Hu NW, Qi Y, Klyubin I, Corbett GT, Fraser G, Perkinton MS, Walsh DM, Billinton A, Rowan MJ. Soluble tau aggregates inhibit synaptic long-term depression and amyloid β-facilitated LTD in vivo. Neurobiol Dis 2019; 127:582-590. [PMID: 30910746 DOI: 10.1016/j.nbd.2019.03.022] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 03/01/2019] [Accepted: 03/21/2019] [Indexed: 01/29/2023] Open
Abstract
Soluble synaptotoxic aggregates of the main pathological proteins of Alzheimer's disease, amyloid β-protein (Aß) and tau, have rapid and potent inhibitory effects on long-term potentiation (LTP). Although the promotion of synaptic weakening mechanisms, including long-term depression (LTD), is posited to mediate LTP inhibition by Aß, little is known regarding the action of exogenous tau on LTD. The present study examined the ability of different assemblies of full-length human tau to affect LTD in the dorsal hippocampus of the anaesthetized rat. Unlike Aß, intracerebroventricular injection of soluble aggregates of tau (SτAs), but not monomers or fibrils, potently increased the threshold for LTD induction in a manner that required cellular prion protein. However, MTEP, an antagonist of the putative prion protein coreceptor metabotropic glutamate receptor 5, did not prevent the disruption of synaptic plasticity by SτAs. In contrast, systemic treatment with Ro 25-6981, a selective antagonist at GluN2B subunit-containing NMDA receptors, reduced SτA-mediated inhibition of LTD, but not LTP. Intriguingly, SτAs completely blocked Aß-facilitated LTD, whereas a subthreshold dose of SτAs facilitated Aß-mediated inhibition of LTP. Overall, these findings support the importance of cellular prion protein in mediating a range of, sometimes opposing, actions of soluble Aß and tau aggregates with different effector mechanisms on synaptic plasticity.
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Affiliation(s)
- Tomas Ondrejcak
- Department of Pharmacology & Therapeutics, Institute of Neuroscience, Trinity College, Dublin 2, Ireland.
| | - Neng-Wei Hu
- Department of Pharmacology & Therapeutics, Institute of Neuroscience, Trinity College, Dublin 2, Ireland; Department of Physiology and Neurobiology, Zhengzhou University School of Medicine, Zhengzhou 450001, China
| | - Yingjie Qi
- Department of Pharmacology & Therapeutics, Institute of Neuroscience, Trinity College, Dublin 2, Ireland
| | - Igor Klyubin
- Department of Pharmacology & Therapeutics, Institute of Neuroscience, Trinity College, Dublin 2, Ireland
| | - Grant T Corbett
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham & Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Graham Fraser
- Neuroscience, IMED Biotech Unit, AstraZeneca, Cambridge CB21 6GH, UK
| | | | - Dominic M Walsh
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham & Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Andrew Billinton
- Neuroscience, IMED Biotech Unit, AstraZeneca, Cambridge CB21 6GH, UK
| | - Michael J Rowan
- Department of Pharmacology & Therapeutics, Institute of Neuroscience, Trinity College, Dublin 2, Ireland.
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Stepler KE, Robinson RAS. The Potential of ‘Omics to Link Lipid Metabolism and Genetic and Comorbidity Risk Factors of Alzheimer’s Disease in African Americans. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1118:1-28. [DOI: 10.1007/978-3-030-05542-4_1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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