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Yancey KL, Patro A, Smetak M, Perkins EL, Isaacson B, Bennett ML, O'Malley M, Haynes DS, Hunter JB. Evaluating calcium channel blockers and bisphosphonates as otoprotective agents in cochlear implantation hearing preservation candidates. Cochlear Implants Int 2024; 25:131-139. [PMID: 38738388 DOI: 10.1080/14670100.2024.2338003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2024]
Abstract
OBJECTIVES Evaluate potential effects of calcium channel blockers (CCB) and bisphosphonates (BP) on residual hearing following cochlear implantation. METHODS Medications of 303 adult hearing preservation (HP) candidates (low frequency pure tone average [LFPTA] of 125, 250, and 500 Hz ≤80 dB HL) were reviewed. Postimplantation LFPTA of patients taking CCBs and BPs were compared to controls matched by age and preimplantation LFPTA. RESULTS Twenty-six HP candidates were taking a CCB (N = 14) or bisphosphonate (N = 12) at implantation. Median follow-up was 1.37 years (range 0.22-4.64y). Among subjects with initial HP, 29% (N = 2 of 7) CCB users compared to 50% (N = 2 of 4) controls subsequently lost residual hearing 3-6 months later (OR = 0.40, 95% CI = 0.04-4.32, p = 0.58). None of the four BP patients with initial HP experienced delayed loss compared to 50% (N = 2 of 4) controls with initial HP (OR = 0.00, 95% CI = 0.00-1.95, P = 0.43). Two CCB and one BP patients improved to a LFPTA <80 dB HL following initial unaided thresholds that suggested loss of residual hearing. DISCUSSION There were no significant differences in the odds of delayed loss of residual hearing with CCBs or BPs. CONCLUSION Further investigation into potential otoprotective adjuvants for maintaining residual hearing following initial successful hearing preservation is warranted, with larger cohorts and additional CCB/BP agents.
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Affiliation(s)
- Kristen L Yancey
- Department of Otolaryngology-Head and Neck Surgery, Weill Cornell Medical Center/New York Presbyterian Hospital, New York, NY, USA
| | - Ankita Patro
- Department of Otolaryngology-Head and Neck Surgery, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Miriam Smetak
- Department of Otolaryngology-Head and Neck Surgery, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Elizabeth L Perkins
- Department of Otolaryngology-Head and Neck Surgery, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Brandon Isaacson
- Department of Otolaryngology-Head and Neck Surgery, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Marc L Bennett
- Department of Otolaryngology-Head and Neck Surgery, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Matthew O'Malley
- Department of Otolaryngology-Head and Neck Surgery, Vanderbilt University Medical Center, Nashville, TN, USA
| | - David S Haynes
- Department of Otolaryngology-Head and Neck Surgery, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Jacob B Hunter
- Department of Otolaryngology-Head and Neck Surgery, Thomas Jefferson University Hospital, Philadelphia, PA, USA
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Zhong R, Xu Y, Williams JW, Li L. Loss of TREM2 exacerbates parenchymal amyloid pathology but diminishes CAA in Tg-SwDI mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.04.565659. [PMID: 37961542 PMCID: PMC10635150 DOI: 10.1101/2023.11.04.565659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease, and it is the most common cause of dementia worldwide. Recent genome-wide association studies (GWAS) identified TREM2 (triggering receptor expressed on myeloid cells 2) as one of the major risk factors for AD. TREM2 is a surface receptor expressed on microglia and largely mediates microglial functions and immune homeostasis in the brain. The functions of TREM2 in AD pathogenesis, including in the formation of the key pathology parenchymal amyloid-β (Aβ) plaques, have been investigated by introducing Trem2 deficiency in AD mouse models. However, the role of TREM2 in cerebrovascular amyloidosis, in particular cerebral amyloid angiopathy (CAA) remains unexplored. CAA features Aβ deposition along the cerebral vessels, signifying an intersection between AD and vascular dysfunction. Using a well-characterized CAA-prone, transgenic mouse model of AD, Tg-SwDI (SwDI), we found that loss of TREM2 led to a marked increase in overall Aβ load in the brain, but a dramatic decrease in CAA in microvessel-rich regions, along with reduced microglial association with CAA. Transcriptomic analysis revealed that in the absence of Trem2 , microglia were activated but trapped in transition to the fully reactive state. Like microglia, perivascular macrophages were activated with upregulation of cell junction related pathways in Trem2 -deficient SwDI mice. In addition, vascular mural cells and astrocytes exhibited distinct responses to Trem2 deficiency, contributing to the pathological changes in the brain of Trem2 -null SwDI mice. Our study provides the first evidence that TREM2 differentially modulates parenchymal and vascular Aβ pathologies, which may have significant implications for both TREM2- and Aβ-targeting therapies for AD.
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3
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Jung D, Bachmann HS. Regulation of protein prenylation. Biomed Pharmacother 2023; 164:114915. [PMID: 37236024 DOI: 10.1016/j.biopha.2023.114915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 05/17/2023] [Accepted: 05/18/2023] [Indexed: 05/28/2023] Open
Abstract
Prenyltransferases (PTases) are known to play a role in embryonic development, normal tissue homeostasis and cancer by posttranslationally modifying proteins involved in these processes. They are being discussed as potential drug targets in an increasing number of diseases, ranging from Alzheimer's disease to malaria. Protein prenylation and the development of specific PTase inhibitors (PTIs) have been subject to intense research in recent decades. Recently, the FDA approved lonafarnib, a specific farnesyltransferase inhibitor that acts directly on protein prenylation; and bempedoic acid, an ATP citrate lyase inhibitor that might alter intracellular isoprenoid composition, the relative concentrations of which can exert a decisive influence on protein prenylation. Both drugs represent the first approved agent in their respective substance class. Furthermore, an overwhelming number of processes and proteins that regulate protein prenylation have been identified over the years, many of which have been proposed as molecular targets for pharmacotherapy in their own right. However, certain aspects of protein prenylation, such as the regulation of PTase gene expression or the modulation of PTase activity by phosphorylation, have attracted less attention, despite their reported influence on tumor cell proliferation. Here, we want to summarize the advances regarding our understanding of the regulation of protein prenylation and the potential implications for drug development. Additionally, we want to suggest new lines of investigation that encompass the search for regulatory elements for PTases, especially at the genetic and epigenetic levels.
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Affiliation(s)
- Dominik Jung
- Institute of Pharmacology and Toxicology, Center for Biomedical Education and Research (ZBAF), School of Medicine, Faculty of Health, Witten/Herdecke University, Witten, Germany
| | - Hagen S Bachmann
- Institute of Pharmacology and Toxicology, Center for Biomedical Education and Research (ZBAF), School of Medicine, Faculty of Health, Witten/Herdecke University, Witten, Germany.
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Qu W, Jeong A, Zhong R, Thieschafer JS, Gram A, Li L. Deletion of Small GTPase H-Ras Rescues Memory Deficits and Reduces Amyloid Plaque-Associated Dendritic Spine Loss in Transgenic Alzheimer's Mice. Mol Neurobiol 2023; 60:495-511. [PMID: 36287323 PMCID: PMC10771223 DOI: 10.1007/s12035-022-03082-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 09/27/2022] [Indexed: 01/25/2023]
Abstract
Alzheimer's disease (AD) is a fatal neurodegenerative disorder, affecting millions of lives without a cure. While the molecular mechanism of AD remains obscure, emerging evidence suggests that small GTPases, a group of GTP-binding proteins that regulate a plethora of essential cellular events, modulate the pathogenic process of AD. Among those, the small GTPase H-Ras, extensively studied in cancer, regulates synaptic function, and both upstream and downstream signaling pathways of H-Ras have been implicated in AD. However, the role of H-Ras per se in AD pathogenesis had not been explored previously. In the present study, the impact of Hras deletion on cognitive function and amyloid pathology was investigated in transgenic APP/PS1 mice of AD. Behavioral assessments showed that the absence of Hras rescued spatial memory deficit in APP/PS1 mice at 9 months of age. The pathological evaluation demonstrated that Hras deletion reduced cortical amyloid deposition and astrogliosis. Furthermore, Hras deficiency protected against amyloid plaque-associated loss of dendritic spines in APP/PS1 mice. Intriguingly, canonical signaling pathways downstream of H-Ras were not affected by the absence of Hras in the brain. Unbiased transcriptomic analysis revealed that lack of H-Ras affected the expression of select genes in the brain of AD mice and identified a novel connection between H-Ras and Annexin A4, a calcium-dependent phospholipid-binding protein that has been shown to regulate membrane repair, neuroinflammation, and calcium homeostasis. Taken together, these data indicate that H-Ras modifies the pathogenic process of AD and may serve as a potential therapeutic target for AD.
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Affiliation(s)
- Wenhui Qu
- Graduate Program in Neuroscience, University of Minnesota, Minneapolis, MN, 55455, USA
- Department of Pathology & Cell Biology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, 10032, USA
| | - Angela Jeong
- Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, MN, 55455, USA
- Division of Pharmacotherapy and Experimental Therapeutics, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Rui Zhong
- Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Josslen S Thieschafer
- Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Andrea Gram
- Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Ling Li
- Graduate Program in Neuroscience, University of Minnesota, Minneapolis, MN, 55455, USA.
- Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, MN, 55455, USA.
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Jeong A, Auger SA, Maity S, Fredriksen K, Zhong R, Li L, Distefano MD. In Vivo Prenylomic Profiling in the Brain of a Transgenic Mouse Model of Alzheimer's Disease Reveals Increased Prenylation of a Key Set of Proteins. ACS Chem Biol 2022; 17:2863-2876. [PMID: 36109170 PMCID: PMC9799064 DOI: 10.1021/acschembio.2c00486] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Dysregulation of protein prenylation has been implicated in many diseases, including Alzheimer's disease (AD). Prenylomic analysis, the combination of metabolic incorporation of an isoprenoid analogue (C15AlkOPP) into prenylated proteins with a bottom-up proteomic analysis, has allowed the identification of prenylated proteins in various cellular models. Here, transgenic AD mice were administered with C15AlkOPP through intracerebroventricular (ICV) infusion over 13 days. Using prenylomic analysis, 36 prenylated proteins were enriched in the brains of AD mice. Importantly, the prenylated forms of 15 proteins were consistently upregulated in AD mice compared to nontransgenic wild-type controls. These results highlight the power of this in vivo metabolic labeling approach to identify multiple post-translationally modified proteins that may serve as potential therapeutic targets for a disease that has proved refractory to treatment thus far. Moreover, this method should be applicable to many other types of protein modifications, significantly broadening its scope.
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Affiliation(s)
- Angela Jeong
- University of Minnesota, Minneapolis, MN, 55455 USA
| | | | - Sanjay Maity
- University of Minnesota, Minneapolis, MN, 55455 USA
| | | | - Rui Zhong
- University of Minnesota, Minneapolis, MN, 55455 USA
| | - Ling Li
- University of Minnesota, Minneapolis, MN, 55455 USA
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Rudajev V, Novotny J. Cholesterol as a key player in amyloid β-mediated toxicity in Alzheimer’s disease. Front Mol Neurosci 2022; 15:937056. [PMID: 36090253 PMCID: PMC9453481 DOI: 10.3389/fnmol.2022.937056] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 07/27/2022] [Indexed: 11/13/2022] Open
Abstract
Alzheimer’s disease (AD) is a neurodegenerative disorder that is one of the most devastating and widespread diseases worldwide, mainly affecting the aging population. One of the key factors contributing to AD-related neurotoxicity is the production and aggregation of amyloid β (Aβ). Many studies have shown the ability of Aβ to bind to the cell membrane and disrupt its structure, leading to cell death. Because amyloid damage affects different parts of the brain differently, it seems likely that not only Aβ but also the nature of the membrane interface with which the amyloid interacts, helps determine the final neurotoxic effect. Because cholesterol is the dominant component of the plasma membrane, it plays an important role in Aβ-induced toxicity. Elevated cholesterol levels and their regulation by statins have been shown to be important factors influencing the progression of neurodegeneration. However, data from many studies have shown that cholesterol has both neuroprotective and aggravating effects in relation to the development of AD. In this review, we attempt to summarize recent findings on the role of cholesterol in Aβ toxicity mediated by membrane binding in the pathogenesis of AD and to consider it in the broader context of the lipid composition of cell membranes.
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Cuddy LK, Alia AO, Salvo MA, Chandra S, Grammatopoulos TN, Justman CJ, Lansbury PT, Mazzulli JR, Vassar R. Farnesyltransferase inhibitor LNK-754 attenuates axonal dystrophy and reduces amyloid pathology in mice. Mol Neurodegener 2022; 17:54. [PMID: 35987691 PMCID: PMC9392365 DOI: 10.1186/s13024-022-00561-9] [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: 01/25/2022] [Accepted: 08/11/2022] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Amyloid plaque deposition and axonal degeneration are early events in AD pathogenesis. Aβ disrupts microtubules in presynaptic dystrophic neurites, resulting in the accumulation of impaired endolysosomal and autophagic organelles transporting β-site amyloid precursor protein cleaving enzyme (BACE1). Consequently, dystrophic neurites generate Aβ42 and significantly contribute to plaque deposition. Farnesyltransferase inhibitors (FTIs) have recently been investigated for repositioning toward the treatment of neurodegenerative disorders and block the action of farnesyltransferase (FTase) to catalyze farnesylation, a post-translational modification that regulates proteins involved in lysosome function and microtubule stability. In postmortem AD brains, FTase and its downstream signaling are upregulated. However, the impact of FTIs on amyloid pathology and dystrophic neurites is unknown. METHODS We tested the effects of the FTIs LNK-754 and lonafarnib in the 5XFAD mouse model of amyloid pathology. RESULTS In 2-month-old 5XFAD mice treated chronically for 3 months, LNK-754 reduced amyloid plaque burden, tau hyperphosphorylation, and attenuated the accumulation of BACE1 and LAMP1 in dystrophic neurites. In 5-month-old 5XFAD mice treated acutely for 3 weeks, LNK-754 reduced dystrophic neurite size and LysoTracker-Green accumulation in the absence of effects on Aβ deposits. Acute treatment with LNK-754 improved memory and learning deficits in hAPP/PS1 amyloid mice. In contrast to LNK-754, lonafarnib treatment was less effective at reducing plaques, tau hyperphosphorylation and dystrophic neurites, which could have resulted from reduced potency against FTase compared to LNK-754. We investigated the effects of FTIs on axonal trafficking of endolysosomal organelles and found that lonafarnib and LNK-754 enhanced retrograde axonal transport in primary neurons, indicating FTIs could support the maturation of axonal late endosomes into lysosomes. Furthermore, FTI treatment increased levels of LAMP1 in mouse primary neurons and in the brains of 5XFAD mice, demonstrating that FTIs stimulated the biogenesis of endolysosomal organelles. CONCLUSIONS We show new data to suggest that LNK-754 promoted the axonal trafficking and function of endolysosomal compartments, which we hypothesize decreased axonal dystrophy, reduced BACE1 accumulation and inhibited amyloid deposition in 5XFAD mice. Our results agree with previous work identifying FTase as a therapeutic target for treating proteinopathies and could have important therapeutic implications in treating AD.
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Affiliation(s)
- Leah K. Cuddy
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
| | - Alia O. Alia
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
| | - Miranda A. Salvo
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
| | - Sidhanth Chandra
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
| | | | | | - Peter T. Lansbury
- Bial Biotech, Cambridge, MA 02139 USA
- Department of Neurology, Harvard Medical School, Cambridge, MA 02139 USA
| | - Joseph R. Mazzulli
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
| | - Robert Vassar
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
- Mesulam Center for Cognitive Neurology and Alzheimer’s Disease, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
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8
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Wu M, Zhai Y, Liang X, Chen W, Lin R, Ma L, Huang Y, Zhao D, Liang Y, Zhao W, Fang J, Fang S, Chen Y, Wang Q, Li W. Connecting the Dots Between Hypercholesterolemia and Alzheimer’s Disease: A Potential Mechanism Based on 27-Hydroxycholesterol. Front Neurosci 2022; 16:842814. [PMID: 35464321 PMCID: PMC9021879 DOI: 10.3389/fnins.2022.842814] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Accepted: 03/01/2022] [Indexed: 12/13/2022] Open
Abstract
Alzheimer’s disease (AD), the most common cause of dementia, is a complex and multifactorial disease involving genetic and environmental factors, with hypercholesterolemia considered as one of the risk factors. Numerous epidemiological studies have reported a positive association between AD and serum cholesterol levels, and experimental studies also provide evidence that elevated cholesterol levels accelerate AD pathology. However, the underlying mechanism of hypercholesterolemia accelerating AD pathogenesis is not clear. Here, we review the metabolism of cholesterol in the brain and focus on the role of oxysterols, aiming to reveal the link between hypercholesterolemia and AD. 27-hydroxycholesterol (27-OHC) is the major peripheral oxysterol that flows into the brain, and it affects β-amyloid (Aβ) production and elimination as well as influencing other pathogenic mechanisms of AD. Although the potential link between hypercholesterolemia and AD is well established, cholesterol-lowering drugs show mixed results in improving cognitive function. Nevertheless, drugs that target cholesterol exocytosis and conversion show benefits in improving AD pathology. Herbs and natural compounds with cholesterol-lowering properties also have a potential role in ameliorating cognition. Collectively, hypercholesterolemia is a causative risk factor for AD, and 27-OHC is likely a potential mechanism for hypercholesterolemia to promote AD pathology. Drugs that regulate cholesterol metabolism are probably beneficial for AD, but more research is needed to unravel the mechanisms involved in 27-OHC, which may lead to new therapeutic strategies for AD.
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Affiliation(s)
- Mingan Wu
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yingying Zhai
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Xiaoyi Liang
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Weichun Chen
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Ruiyi Lin
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Linlin Ma
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yi Huang
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Di Zhao
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yong Liang
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Wei Zhao
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Jiansong Fang
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Shuhuan Fang
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yunbo Chen
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Qi Wang
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
- *Correspondence: Qi Wang,
| | - Weirong Li
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
- Weirong Li,
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9
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Weber AJ, Adamson AB, Greathouse KM, Andrade JP, Freeman CD, Seo JV, Rae RJ, Walker CK, Herskowitz JH. Conditional deletion of ROCK2 induces anxiety-like behaviors and alters dendritic spine density and morphology on CA1 pyramidal neurons. Mol Brain 2021; 14:169. [PMID: 34794469 PMCID: PMC8600782 DOI: 10.1186/s13041-021-00878-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 11/04/2021] [Indexed: 12/25/2022] Open
Abstract
Rho-associated kinase isoform 2 (ROCK2) is an attractive drug target for several neurologic disorders. A critical barrier to ROCK2-based research and therapeutics is the lack of a mouse model that enables investigation of ROCK2 with spatial and temporal control of gene expression. To overcome this, we generated ROCK2fl/fl mice. Mice expressing Cre recombinase in forebrain excitatory neurons (CaMKII-Cre) were crossed with ROCK2fl/fl mice (Cre/ROCK2fl/fl), and the contribution of ROCK2 in behavior as well as dendritic spine morphology in the hippocampus, medial prefrontal cortex (mPFC), and basolateral amygdala (BLA) was examined. Cre/ROCK2fl/fl mice spent reduced time in the open arms of the elevated plus maze and increased time in the dark of the light-dark box test compared to littermate controls. These results indicated that Cre/ROCK2fl/fl mice exhibited anxiety-like behaviors. To examine dendritic spine morphology, individual pyramidal neurons in CA1 hippocampus, mPFC, and the BLA were targeted for iontophoretic microinjection of fluorescent dye, followed by high-resolution confocal microscopy and neuronal 3D reconstructions for morphometry analysis. In dorsal CA1, Cre/ROCK2fl/fl mice displayed significantly increased thin spine density on basal dendrites and reduced mean spine head volume across all spine types on apical dendrites. In ventral CA1, Cre/ROCK2fl/fl mice exhibited significantly increased spine length on apical dendrites. Spine density and morphology were comparable in the mPFC and BLA between both genotypes. These findings suggest that neuronal ROCK2 mediates spine density and morphology in a compartmentalized manner among CA1 pyramidal cells, and that in the absence of ROCK2 these mechanisms may contribute to anxiety-like behaviors.
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Affiliation(s)
- Audrey J Weber
- Center for Neurodegeneration and Experimental Therapeutics, Department of Neurology, University of Alabama at Birmingham, 1825 University Blvd, Birmingham, AL, 35294, USA
| | - Ashley B Adamson
- Center for Neurodegeneration and Experimental Therapeutics, Department of Neurology, University of Alabama at Birmingham, 1825 University Blvd, Birmingham, AL, 35294, USA
| | - Kelsey M Greathouse
- Center for Neurodegeneration and Experimental Therapeutics, Department of Neurology, University of Alabama at Birmingham, 1825 University Blvd, Birmingham, AL, 35294, USA
| | - Julia P Andrade
- Center for Neurodegeneration and Experimental Therapeutics, Department of Neurology, University of Alabama at Birmingham, 1825 University Blvd, Birmingham, AL, 35294, USA
| | - Cameron D Freeman
- Center for Neurodegeneration and Experimental Therapeutics, Department of Neurology, University of Alabama at Birmingham, 1825 University Blvd, Birmingham, AL, 35294, USA
| | - Jung Vin Seo
- Center for Neurodegeneration and Experimental Therapeutics, Department of Neurology, University of Alabama at Birmingham, 1825 University Blvd, Birmingham, AL, 35294, USA
| | - Rosaria J Rae
- Center for Neurodegeneration and Experimental Therapeutics, Department of Neurology, University of Alabama at Birmingham, 1825 University Blvd, Birmingham, AL, 35294, USA
| | - Courtney K Walker
- Center for Neurodegeneration and Experimental Therapeutics, Department of Neurology, University of Alabama at Birmingham, 1825 University Blvd, Birmingham, AL, 35294, USA
| | - Jeremy H Herskowitz
- Center for Neurodegeneration and Experimental Therapeutics, Department of Neurology, University of Alabama at Birmingham, 1825 University Blvd, Birmingham, AL, 35294, USA.
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Jeong A, Cheng S, Zhong R, Bennett DA, Bergö MO, Li L. Protein farnesylation is upregulated in Alzheimer's human brains and neuron-specific suppression of farnesyltransferase mitigates pathogenic processes in Alzheimer's model mice. Acta Neuropathol Commun 2021; 9:129. [PMID: 34315531 PMCID: PMC8314463 DOI: 10.1186/s40478-021-01231-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 07/16/2021] [Indexed: 11/10/2022] Open
Abstract
The pathogenic mechanisms underlying the development of Alzheimer's disease (AD) remain elusive and to date there are no effective prevention or treatment for AD. Farnesyltransferase (FT) catalyzes a key posttranslational modification process called farnesylation, in which the isoprenoid farnesyl pyrophosphate is attached to target proteins, facilitating their membrane localization and their interactions with downstream effectors. Farnesylated proteins, including the Ras superfamily of small GTPases, are involved in regulating diverse physiological and pathological processes. Emerging evidence suggests that isoprenoids and farnesylated proteins may play an important role in the pathogenesis of AD. However, the dynamics of FT and protein farnesylation in human brains and the specific role of neuronal FT in the pathogenic progression of AD are not known. Here, using postmortem brain tissue from individuals with no cognitive impairment (NCI), mild cognitive impairment (MCI), or Alzheimer's dementia, we found that the levels of FT and membrane-associated H-Ras, an exclusively farnesylated protein, and its downstream effector ERK were markedly increased in AD and MCI compared with NCI. To elucidate the specific role of neuronal FT in AD pathogenesis, we generated the transgenic AD model APP/PS1 mice with forebrain neuron-specific FT knockout, followed by a battery of behavioral assessments, biochemical assays, and unbiased transcriptomic analysis. Our results showed that the neuronal FT deletion mitigates memory impairment and amyloid neuropathology in APP/PS1 mice through suppressing amyloid generation and reversing the pathogenic hyperactivation of mTORC1 signaling. These findings suggest that aberrant upregulation of protein farnesylation is an early driving force in the pathogenic cascade of AD and that targeting FT or its downstream signaling pathways presents a viable therapeutic strategy against AD.
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11
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Zhao D, Yi Y, He Q, Wang S, Yang K, Ge J. Exploring the regulatory mechanism of Nao Tai Fang on vascular Dementia's biological network based on cheminformatics and transcriptomics strategy. JOURNAL OF ETHNOPHARMACOLOGY 2021; 274:114065. [PMID: 33771644 DOI: 10.1016/j.jep.2021.114065] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 03/16/2021] [Accepted: 03/18/2021] [Indexed: 06/12/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Nao Tai Fang (NTF) is modified from Buyang Huanwu Decoction. Modern pharmacological research showed that NTF has a good anti-cerebral ischemic effect and can improve the learning and memory ability of cerebrovascular disease. AIM The purpose of this study is to explore the regulation mechanism of NTF on the regulation mechanism of vascular dementia (VD)'s biological network based on chemoinformatics and transcriptomics strategies. METHOD First, the bilateral common carotid artery ligation method was used to create a rat VD model. After NTF intervention for 30 days, the treatment effect was evaluated by HE staining and water maze experiment. Then, the Agilent mRNA expression profiling chip was used to obtain mRNA expression data of hippocampal tissues of VD model rats before and after NTF intervention, and microarray analysis was used to screen for genes with significant differential expression. The BATMAN database was utilized to obtain the potential targets of NTF and the Genecards and OMIM were utilized to collect the VD potential genes. The cytoscape was utilized to construct and analyze the networks. RESULT The animal experiments showed that NTF can improve VD. A total of 180 up-regulated proteins and 289 down-regulated proteins were identified. The top 20 up- and down-regulated differentially expressed genes were utilized to construct differentially expressed gene's protein-protein interaction (PPI) network. A total of 677 NTF potential targets and 550 VD genes were obtained and were utilized to construct NTF-VD PPI network. The cheminformatics analysis showed that NTF can regulate a lot of biological processes and signaling pathways (such as inflammation modules, vasodilation and contraction modules, hypoxia modules, angiogenesis, coagulation, neurovascular unit modules, Neuroactive ligand-receptor interaction, Calcium signaling pathway, Serotonergic synapse). CONCLUSION NTF may play a role in the treatment of VD through the targets, signaling pathways and biological processes discovered in this study.
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Affiliation(s)
- Da Zhao
- Hunan University of Chinese Medicine, Hunan, China
| | - Yaqiao Yi
- Hunan University of Chinese Medicine, Hunan, China
| | - Qi He
- Hunan University of Chinese Medicine, Hunan, China
| | | | - Kailin Yang
- Hunan University of Chinese Medicine, Hunan, China; Capital Medical University, Beijing, China.
| | - Jinwen Ge
- Hunan University of Chinese Medicine, Hunan, China; Shaoyang University, Hunan, China.
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12
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Ötzkan S, Muller WE, Gibson Wood W, Eckert GP. Effects of 7,8-Dihydroxyflavone on Lipid Isoprenoid and Rho Protein Levels in Brains of Aged C57BL/6 Mice. Neuromolecular Med 2020; 23:130-139. [PMID: 33377988 PMCID: PMC7929957 DOI: 10.1007/s12017-020-08640-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 11/25/2020] [Indexed: 12/13/2022]
Abstract
Synaptic impairment may be the main cause of cognitive dysfunction in brain aging that is probably due to a reduction in synaptic contact between the axonal buttons and dendritic spines. Rho proteins including the small GTPase Rac1 have become key regulators of neuronal morphogenesis that supports synaptic plasticity. Small Rho- and Ras-GTPases are post-translationally modified by the isoprenoids geranylgeranyl pyrophosphate (GGPP) and farnesyl pyrophosphate (FPP), respectively. For all GTPases, anchoring in the plasma membrane is essential for their activation by guanine nucleotide exchange factors (GEFs). Rac1-specific GEFs include the protein T lymphoma invasion and metastasis 1 (Tiam1). Tiam1 interacts with the TrkB receptor to mediate the brain-derived neurotrophic factor (BDNF)-induced activation of Rac1, resulting in cytoskeletal rearrangement and changes in cellular morphology. The flavonoid 7,8-dihydroxyflavone (7,8-DHF) acts as a highly affine-selective TrkB receptor agonist and causes the dimerization and autophosphorylation of the TrkB receptor and thus the activation of downstream signaling pathways. In the current study, we investigated the effects of 7,8-DHF on cerebral lipid isoprenoid and Rho protein levels in male C57BL/6 mice aged 3 and 23 months. Aged mice were daily treated with 100 mg/kg b.w. 7,8-DHF by oral gavage for 21 days. FPP, GGPP, and cholesterol levels were determined in brain tissue. In the same tissue, the protein content of Tiam1 and TrkB in was measured. The cellular localization of the small Rho-GTPase Rac1 and small Rab-GTPase Rab3A was studied in total brain homogenates and membrane preparations. We report the novel finding that 7,8-DHF restored levels of the Rho proteins Rac1 and Rab3A in membrane preparations isolated from brains of treated aged mice. The selective TrkB agonist 7,8-DHF did not affect BDNF and TrkB levels, but restored Tiam1 levels that were found to be reduced in brains of aged mice. FPP, GGPP, and cholesterol levels were significantly elevated in brains of aged mice but not changed by 7,8-DHF treatment. Hence, 7,8-DHF may be useful as pharmacological tool to treat age-related cognitive dysfunction although the underlying mechanisms need to be elucidated in detail.
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Affiliation(s)
- Sarah Ötzkan
- Department of Pharmacology, Biocenter Niederursel, University of Frankfurt, Goethe-University, Max-von-Laue-St. 9, 60438, Frankfurt, Germany
| | - Walter E Muller
- Department of Pharmacology, Biocenter Niederursel, University of Frankfurt, Goethe-University, Max-von-Laue-St. 9, 60438, Frankfurt, Germany
| | - W Gibson Wood
- Department of Pharmacology, Geriatric Research, Education and Clinical Center, University of Minnesota School of Medicine, VAMC, Minneapolis, MN, 55417, USA
| | - Gunter P Eckert
- Department of Pharmacology, Biocenter Niederursel, University of Frankfurt, Goethe-University, Max-von-Laue-St. 9, 60438, Frankfurt, Germany.
- Institute of Nutritional Sciences, Laboratory for Nutrition in Prevention and Therapy, Justus-Liebig-University of Giessen, Biomedical Research Center Seltersberg (BFS), Schubertstr. 81, 35392, Giessen, Germany.
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Song Z, Li F, He C, Yu J, Li P, Li Z, Yang M, Cheng S. In-depth transcriptomic analyses of LncRNA and mRNA expression in the hippocampus of APP/PS1 mice by Danggui-Shaoyao-San. Aging (Albany NY) 2020; 12:23945-23959. [PMID: 33221745 PMCID: PMC7762474 DOI: 10.18632/aging.104068] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 08/17/2020] [Indexed: 12/21/2022]
Abstract
Alzheimer’s disease (AD) is an age-related neurodegenerative disease with a high incidence worldwide, and with no medications currently able to prevent the progression of AD. Danggui-Shaoyao-San (DSS) is widely used in traditional Chinese medicine (TCM) and has been proven to be effective for memory and cognitive dysfunction, yet its precise mechanism remains to be delineated. The present study was designed to investigate the genome-wide expression profile of long non-coding RNAs (LncRNAs) and messenger RNAs (mRNAs) in the hippocampus of APP/PS1 mice after DSS treatment by RNA sequencing. A total of 285 differentially expressed LncRNAs and 137 differentially expressed mRNAs were identified (fold-change ≥2.0 and P < 0.05). Partial differentially expressed LncRNAs and mRNAs were selected to verify the RNA sequencing results by quantitative polymerase chain reaction (qPCR). A co-expression network was established to analyze co-expressed LncRNAs and genes. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were used to evaluate the biological functions related to the differentially co-expressed LncRNAs, and the results showed that the co-expressed LncRNAs were mainly involved in AD development from distinct origins, such as APP processing, neuron migration, and synaptic transmission. Our research describes the lncRNA and mRNA expression profiles and functional networks involved in the therapeutic effect of DSS in APP/PS1 mice model. The results suggest that the therapeutic effect of DSS on AD involves the expression of LncRNAs. Our findings provide a new perspective for research on the treatment of complex diseases using traditional Chinese medicine prescriptions.
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Affiliation(s)
- Zhenyan Song
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-Cerebral Diseases, Hunan University of Chinese Medicine, Changsha 410208, Hunan, China
| | - Fuzhou Li
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-Cerebral Diseases, Hunan University of Chinese Medicine, Changsha 410208, Hunan, China
| | - Chunxiang He
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-Cerebral Diseases, Hunan University of Chinese Medicine, Changsha 410208, Hunan, China
| | - Jingping Yu
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-Cerebral Diseases, Hunan University of Chinese Medicine, Changsha 410208, Hunan, China
| | - Ping Li
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-Cerebral Diseases, Hunan University of Chinese Medicine, Changsha 410208, Hunan, China
| | - Ze Li
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-Cerebral Diseases, Hunan University of Chinese Medicine, Changsha 410208, Hunan, China
| | - Miao Yang
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-Cerebral Diseases, Hunan University of Chinese Medicine, Changsha 410208, Hunan, China
| | - Shaowu Cheng
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-Cerebral Diseases, Hunan University of Chinese Medicine, Changsha 410208, Hunan, China
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Loss of TREM2 Confers Resilience to Synaptic and Cognitive Impairment in Aged Mice. J Neurosci 2020; 40:9552-9563. [PMID: 33139402 DOI: 10.1523/jneurosci.2193-20.2020] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 10/12/2020] [Accepted: 10/27/2020] [Indexed: 11/21/2022] Open
Abstract
Triggering receptor expressed on myeloid cells 2 (TREM2), a receptor exclusively expressed by microglia in the brain, modulates microglial immune homeostasis. Human genetic studies have shown that the loss-of-function mutations in TREM2 signaling are strongly associated with an elevated risk of age-related neurodegenerative diseases including Alzheimer's disease (AD). Numerous studies have investigated the impact of TREM2 deficiency in the pathogenic process of AD. However, the role of TREM2 in shaping neuronal and cognitive function during normal aging is underexplored. In the present study, we employed behavioral, electrophysiological, and biochemical approaches to assess cognitive and synaptic function in male and female young and aged TREM2-deficient (Trem2-/-) mice compared with age-matched, sex-matched, and genetic background-matched wild-type (WT) C57BL/6J controls. Young Trem2-/- mice exhibited normal cognitive function and synaptic plasticity but had increased dendritic spine density compared with young WT. Unexpectedly, aged Trem2-/- mice showed superior cognitive performance compared with aged WT controls. Consistent with the behavioral data, aged Trem2-/- mice displayed significantly enhanced hippocampal long-term potentiation (LTP) and increased dendritic spine density and synaptic markers compared with aged WT mice. Taken together, these findings suggest that loss of TREM2 affects the neuronal structure and confers resilience to age-related synaptic and cognitive impairment during non-pathogenic aging.SIGNIFICANCE STATEMENT Microglia are innate immune cells of the brain that orchestrates neurodevelopment, synaptic function, and immune response to environmental stimuli. Microglial triggering receptor expressed on myeloid cells 2 (TREM2) signaling plays pivotal roles in regulating these functions and loss of TREM2 signaling leads to increased risk of developing age-related neurologic disorders. However, the neurologic role of TREM2 in normal aging is poorly understood. The results of the present study unveil the positive impacts of TREM2 deficiency on cognitive and synaptic function during aging and suggest that TREM2 may exert detrimental effects on neuronal function. The possibility of age-related negative impacts from TREM2 is critically important since TREM2 has emerged as a major therapeutic target for Alzheimer's dementia.
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15
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Qu W, Suazo KF, Liu W, Cheng S, Jeong A, Hottman D, Yuan LL, Distefano MD, Li L. Neuronal Protein Farnesylation Regulates Hippocampal Synaptic Plasticity and Cognitive Function. Mol Neurobiol 2020; 58:1128-1144. [PMID: 33098528 DOI: 10.1007/s12035-020-02169-w] [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: 07/08/2020] [Accepted: 10/12/2020] [Indexed: 12/30/2022]
Abstract
Protein prenylation is a post-translational lipid modification that governs a variety of important cellular signaling pathways, including those regulating synaptic functions and cognition in the nervous system. Two enzymes, farnesyltransferase (FT) and geranylgeranyltransferase type I (GGT), are essential for the prenylation process. Genetic reduction of FT or GGT ameliorates neuropathology but only FT haplodeficiency rescues cognitive function in transgenic mice of Alzheimer's disease. A follow-up study showed that systemic or forebrain neuron-specific deficiency of GGT leads to synaptic and cognitive deficits under physiological conditions. Whether FT plays different roles in shaping neuronal functions and cognition remains elusive. This study shows that in contrast to the detrimental effects of GGT reduction, systemic haplodeficiency of FT has little to no impact on hippocampal synaptic plasticity and cognition. However, forebrain neuron-specific FT deletion also leads to reduced synaptic plasticity, memory retention, and hippocampal dendritic spine density. Furthermore, a novel prenylomic analysis identifies distinct pools of prenylated proteins that are affected in the brain of forebrain neuron-specific FT and GGT knockout mice, respectively. Taken together, this study uncovers that physiological levels of FT and GGT in neurons are essential for normal synaptic/cognitive functions and that the prenylation status of specific signaling molecules regulates neuronal functions.
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Affiliation(s)
- Wenhui Qu
- Graduate Program in Neuroscience, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Kiall F Suazo
- Department of Chemistry, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Wenfeng Liu
- Department of Experimental and Clinical Pharmacology, University of Minnesota, McGuire Translational Research Facility (MTRF) 4-208, 2001 6th Street SE, Minneapolis, MN, 55455, USA
| | - Shaowu Cheng
- Department of Experimental and Clinical Pharmacology, University of Minnesota, McGuire Translational Research Facility (MTRF) 4-208, 2001 6th Street SE, Minneapolis, MN, 55455, USA
| | - Angela Jeong
- Department of Experimental and Clinical Pharmacology, University of Minnesota, McGuire Translational Research Facility (MTRF) 4-208, 2001 6th Street SE, Minneapolis, MN, 55455, USA
| | - David Hottman
- Department of Experimental and Clinical Pharmacology, University of Minnesota, McGuire Translational Research Facility (MTRF) 4-208, 2001 6th Street SE, Minneapolis, MN, 55455, USA
| | - Li-Lian Yuan
- Department of Physiology and Pharmacology, Des Moines University, Des Moines, IA, 50312, USA
| | - Mark D Distefano
- Department of Chemistry, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Ling Li
- Graduate Program in Neuroscience, University of Minnesota, Minneapolis, MN, 55455, USA. .,Department of Experimental and Clinical Pharmacology, University of Minnesota, McGuire Translational Research Facility (MTRF) 4-208, 2001 6th Street SE, Minneapolis, MN, 55455, USA. .,Graduate Program in Pharmacology, University of Minnesota, Minneapolis, MN, 55455, USA.
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16
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Seist R, Tong M, Landegger LD, Vasilijic S, Hyakusoku H, Katsumi S, McKenna CE, Edge ASB, Stankovic KM. Regeneration of Cochlear Synapses by Systemic Administration of a Bisphosphonate. Front Mol Neurosci 2020; 13:87. [PMID: 32765216 PMCID: PMC7381223 DOI: 10.3389/fnmol.2020.00087] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 04/28/2020] [Indexed: 12/12/2022] Open
Abstract
Sensorineural hearing loss (SNHL) caused by noise exposure and attendant loss of glutamatergic synapses between cochlear spiral ganglion neurons (SGNs) and hair cells is the most common sensory deficit worldwide. We show here that systemic administration of a bisphosphonate to mice 24 h after synaptopathic noise exposure regenerated synapses between inner hair cells and SGNs and restored cochlear function. We further demonstrate that this effect is mediated by inhibition of the mevalonate pathway. These results are highly significant because they suggest that bisphosphonates could reverse cochlear synaptopathy for the treatment of SNHL.
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Affiliation(s)
- Richard Seist
- Eaton-Peabody Laboratories, Department of Otolaryngology – Head and Neck Surgery, Massachusetts Eye and Ear, Boston, MA, United States
- Department of Otolaryngology – Head and Neck Surgery, Harvard Medical School, Boston, MA, United States
- Department of Otorhinolaryngology-Head and Neck Surgery, Paracelsus Medical University, Salzburg, Austria
| | - Mingjie Tong
- Eaton-Peabody Laboratories, Department of Otolaryngology – Head and Neck Surgery, Massachusetts Eye and Ear, Boston, MA, United States
- Department of Otolaryngology – Head and Neck Surgery, Harvard Medical School, Boston, MA, United States
| | - Lukas D. Landegger
- Eaton-Peabody Laboratories, Department of Otolaryngology – Head and Neck Surgery, Massachusetts Eye and Ear, Boston, MA, United States
- Department of Otolaryngology – Head and Neck Surgery, Harvard Medical School, Boston, MA, United States
- Department of Otorhinolaryngology-Head and Neck Surgery, Medical University of Vienna, Vienna, Austria
| | - Sasa Vasilijic
- Eaton-Peabody Laboratories, Department of Otolaryngology – Head and Neck Surgery, Massachusetts Eye and Ear, Boston, MA, United States
- Department of Otolaryngology – Head and Neck Surgery, Harvard Medical School, Boston, MA, United States
| | - Hiroshi Hyakusoku
- Eaton-Peabody Laboratories, Department of Otolaryngology – Head and Neck Surgery, Massachusetts Eye and Ear, Boston, MA, United States
- Department of Otolaryngology – Head and Neck Surgery, Harvard Medical School, Boston, MA, United States
- Department of Otorhinolaryngology, Yokosuka Kyosai Hospital, Kanagawa, Japan
| | - Sachiyo Katsumi
- Eaton-Peabody Laboratories, Department of Otolaryngology – Head and Neck Surgery, Massachusetts Eye and Ear, Boston, MA, United States
- Department of Otolaryngology – Head and Neck Surgery, Harvard Medical School, Boston, MA, United States
| | - Charles E. McKenna
- Department of Chemistry, University of Southern California, Los Angeles, CA, United States
| | - Albert S. B. Edge
- Eaton-Peabody Laboratories, Department of Otolaryngology – Head and Neck Surgery, Massachusetts Eye and Ear, Boston, MA, United States
- Department of Otolaryngology – Head and Neck Surgery, Harvard Medical School, Boston, MA, United States
- Speech and Hearing Bioscience and Technology Program, Harvard Medical School, Boston, MA, United States
- Harvard Stem Cell Institute, Cambridge, MA, United States
| | - Konstantina M. Stankovic
- Eaton-Peabody Laboratories, Department of Otolaryngology – Head and Neck Surgery, Massachusetts Eye and Ear, Boston, MA, United States
- Department of Otolaryngology – Head and Neck Surgery, Harvard Medical School, Boston, MA, United States
- Speech and Hearing Bioscience and Technology Program, Harvard Medical School, Boston, MA, United States
- Harvard Stem Cell Institute, Cambridge, MA, United States
- Program in Therapeutic Science, Harvard Medical School, Boston, MA, United States
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17
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Xu CJ, Wang JL, Jing-Pan, Min-Liao. Tph2 Genetic Ablation Contributes to Senile Plaque Load and Astrogliosis in APP/PS1 Mice. Curr Alzheimer Res 2020; 16:219-232. [PMID: 30827242 DOI: 10.2174/1567205016666190301110110] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 12/20/2018] [Accepted: 01/11/2019] [Indexed: 01/06/2023]
Abstract
BACKGROUND Amyloid-β (Aβ) accumulation plays a critical role in the pathogenesis of Alzheimer's disease (AD) lesions. Deficiency of Serotonin signaling recently has been linked to the increased Aβ level in transgenic mice and humans. In addition, tryptophan hydroxylase-2 (Tph2), a second tryptophan hydroxylase isoform, controls brain serotonin synthesis. However, it remains to be determined that whether Tph2 deficient APP/PS1mice affect the formation of Aβ plaques in vivo. METHODS Both quantitative and qualitative immunochemistry methods, as well as Congo red staining were used to evaluate the Aβ load and astrogliosis in these animals. RESULTS we studied alterations of cortex and hippocampus in astrocytes and senile plaques by Tph2 conditional knockout (Tph2 CKO) AD mice from 6-10 months of age. Using Congo red staining and immunostained with Aβ antibody, we showed that plaques load or plaques numbers significantly increased in Tph2 CKO experimental groups at 8 to 10 months old, compared to wild type (WT) group, respectively. Using GFAP+ astrocytes immunofluorescence method, we found that the density of GFAP+ astrocytes markedly enhanced in Tph2 CKO at 10 months. We showed Aβ plaques co-localized autophagic markers LC3 and p62. Nevertheless, we did not observe any co-localization between GFAP+ astrocytes and autophagic markers, but detected the co-localization between βIII-tubulin+ neurons and autophagic markers. CONCLUSION Overall, our work provides the preliminary evidence in vivo that Tph2 plays a role in amyloid plaques generation.
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Affiliation(s)
- Chao-Jin Xu
- Department of Histology & Embryology, School of Basic Medical Science, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Jun-Ling Wang
- Centre for Reproductive Medicine, Affiliated Hospital 1 of Wenzhou Medical University, Wenzhou, Zhejiang 325000, China
| | - Jing-Pan
- Department of Histology & Embryology, School of Basic Medical Science, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Min-Liao
- Department of Histology & Embryology, School of Basic Medical Science, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
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Ramesh M, Gopinath P, Govindaraju T. Role of Post-translational Modifications in Alzheimer's Disease. Chembiochem 2020; 21:1052-1079. [PMID: 31863723 DOI: 10.1002/cbic.201900573] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 12/19/2019] [Indexed: 12/22/2022]
Abstract
The global burden of Alzheimer's disease (AD) is growing. Valiant efforts to develop clinical candidates for treatment have continuously met with failure. Currently available palliative treatments are temporary and there is a constant need to search for reliable disease pathways, biomarkers and drug targets for developing diagnostic and therapeutic tools to address the unmet medical needs of AD. Challenges in drug-discovery efforts raise further questions about the strategies of current conventional diagnosis; drug design; and understanding of disease pathways, biomarkers and targets. In this context, post-translational modifications (PTMs) regulate protein trafficking, function and degradation, and their in-depth study plays a significant role in the identification of novel biomarkers and drug targets. Aberrant PTMs of disease-relevant proteins could trigger pathological pathways, leading to disease progression. Advancements in proteomics enable the generation of patterns or signatures of such modifications, and thus, provide a versatile platform to develop biomarkers based on PTMs. In addition, understanding and targeting the aberrant PTMs of various proteins provide viable avenues for addressing AD drug-discovery challenges. This review highlights numerous PTMs of proteins relevant to AD and provides an overview of their adverse effects on the protein structure, function and aggregation propensity that contribute to the disease pathology. A critical discussion offers suggestions of methods to develop PTM signatures and interfere with aberrant PTMs to develop viable diagnostic and therapeutic interventions in AD.
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Affiliation(s)
- Madhu Ramesh
- Bioorganic Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur P.O., Bengaluru, 560064, Karnataka, India
| | - Pushparathinam Gopinath
- Department of Chemistry, SRM-Institute of Science and Technology, Kattankulathur, 603203, Chennai, Tamilnadu, India
| | - Thimmaiah Govindaraju
- Bioorganic Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur P.O., Bengaluru, 560064, Karnataka, India
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19
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Reddy JM, Raut NGR, Seifert JL, Hynds DL. Regulation of Small GTPase Prenylation in the Nervous System. Mol Neurobiol 2020; 57:2220-2231. [PMID: 31989383 DOI: 10.1007/s12035-020-01870-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 01/06/2020] [Indexed: 11/26/2022]
Abstract
Mevalonate pathway inhibitors have been extensively studied for their roles in cholesterol depletion and for inhibiting the prenylation and activation of various proteins. Inhibition of protein prenylation has potential therapeutic uses against neurological disorders, like neural cancers, neurodegeneration, and neurotramatic lesions. Protection against neurodegeneration and promotion of neuronal regeneration is regulated in large part by Ras superfamily small guanosine triphosphatases (GTPases), particularly the Ras, Rho, and Rab subfamilies. These proteins are prenylated to target them to cellular membranes. Prenylation can be specifically inhibited through altering the function of enzymes of the mevalonate pathway necessary for isoprenoid production and attachment to target proteins to elicit a variety of effects on neural cells. However, this approach does not address how prenylation affects a specific protein. This review focuses on the regulation of small GTPase prenylation, the different techniques to inhibit prenylation, and how this inhibition has affected neural cell processes.
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Affiliation(s)
| | | | | | - DiAnna L Hynds
- Texas Woman's University, Denton, TX, USA.
- Woodcock Institute for the Advancement of Neurocognitive Research and Applied Practice, Texas Woman's University, PO Box 4525799, Denton, TX, 76204-5799, USA.
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Jeong A, Suazo KF, Wood WG, Distefano MD, Li L. Isoprenoids and protein prenylation: implications in the pathogenesis and therapeutic intervention of Alzheimer's disease. Crit Rev Biochem Mol Biol 2018; 53:279-310. [PMID: 29718780 PMCID: PMC6101676 DOI: 10.1080/10409238.2018.1458070] [Citation(s) in RCA: 90] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The mevalonate-isoprenoid-cholesterol biosynthesis pathway plays a key role in human health and disease. The importance of this pathway is underscored by the discovery that two major isoprenoids, farnesyl and geranylgeranyl pyrophosphate, are required to modify an array of proteins through a process known as protein prenylation, catalyzed by prenyltransferases. The lipophilic prenyl group facilitates the anchoring of proteins in cell membranes, mediating protein-protein interactions and signal transduction. Numerous essential intracellular proteins undergo prenylation, including most members of the small GTPase superfamily as well as heterotrimeric G proteins and nuclear lamins, and are involved in regulating a plethora of cellular processes and functions. Dysregulation of isoprenoids and protein prenylation is implicated in various disorders, including cardiovascular and cerebrovascular diseases, cancers, bone diseases, infectious diseases, progeria, and neurodegenerative diseases including Alzheimer's disease (AD). Therefore, isoprenoids and/or prenyltransferases have emerged as attractive targets for developing therapeutic agents. Here, we provide a general overview of isoprenoid synthesis, the process of protein prenylation and the complexity of prenylated proteins, and pharmacological agents that regulate isoprenoids and protein prenylation. Recent findings that connect isoprenoids/protein prenylation with AD are summarized and potential applications of new prenylomic technologies for uncovering the role of prenylated proteins in the pathogenesis of AD are discussed.
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Affiliation(s)
- Angela Jeong
- Departments of Experimental and Clinical Pharmacolog,University of Minnesota, Minneapolis, MN 55455
| | | | - W. Gibson Wood
- Departments of Pharmacology, University of Minnesota, Minneapolis, MN 55455
| | - Mark D. Distefano
- Departments of Chemistry,University of Minnesota, Minneapolis, MN 55455
| | - Ling Li
- Departments of Experimental and Clinical Pharmacolog,University of Minnesota, Minneapolis, MN 55455
- Departments of Pharmacology, University of Minnesota, Minneapolis, MN 55455
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21
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Hottman D, Cheng S, Gram A, LeBlanc K, Yuan LL, Li L. Systemic or Forebrain Neuron-Specific Deficiency of Geranylgeranyltransferase-1 Impairs Synaptic Plasticity and Reduces Dendritic Spine Density. Neuroscience 2018; 373:207-217. [PMID: 29406266 DOI: 10.1016/j.neuroscience.2018.01.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Revised: 01/03/2018] [Accepted: 01/13/2018] [Indexed: 01/23/2023]
Abstract
Isoprenoids and prenylated proteins regulate a variety of cellular functions, including neurite growth and synaptic plasticity. Importantly, they are implicated in the pathogenesis of several diseases, including Alzheimer's disease (AD). Recently, we have shown that two protein prenyltransferases, farnesyltransferase (FT) and geranylgeranyltransferase-1 (GGT), have differential effects in a mouse model of AD. Haplodeficiency of either FT or GGT attenuates amyloid-β deposition and neuroinflammation but only reduction in FT rescues cognitive function. The current study aimed to elucidate the potential mechanisms that may account for the lack of cognitive benefit in GGT-haplodeficient mice, despite attenuated neuropathology. The results showed that the magnitude of long-term potentiation (LTP) was markedly suppressed in hippocampal slices from GGT-haplodeficient mice. Consistent with the synaptic dysfunction, there was a significant decrease in cortical spine density and cognitive function in GGT-haplodeficient mice. To further study the neuron-specific effects of GGT deficiency, we generated conditional forebrain neuron-specific GGT-knockout (GGTf/fCre+) mice using a Cre/LoxP system under the CAMKIIα promoter. We found that both the magnitude of hippocampal LTP and the dendritic spine density of cortical neurons were decreased in GGTf/fCre+ mice compared with GGTf/fCre- mice. Immunoblot analyses of cerebral lysate showed a significant reduction in cell membrane-associated (geranylgeranylated) Rac1 and RhoA but not (farnesylated) H-Ras, in GGTf/fCre+ mice, suggesting that insufficient geranylgeranylation of the Rho family of small GTPases may underlie the detrimental effects of GGT deficiency. These findings reinforce the critical role of GGT in maintaining spine structure and synaptic/cognitive function in development and in the mature brain.
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Affiliation(s)
- David Hottman
- Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, MN 55455, United States
| | - Shaowu Cheng
- Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, MN 55455, United States; College of Integrated Traditional Chinese and Western Medicine, Hunan University of Chinese Medicine, Yuelu District, Changsha, Hunan 410208, China
| | - Andrea Gram
- Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, MN 55455, United States
| | - Kyle LeBlanc
- Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, MN 55455, United States
| | - Li-Lian Yuan
- Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, United States; Department of Physiology and Pharmacology, Des Moines University, Des Moines, IA 50312, United States
| | - Ling Li
- Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, MN 55455, United States; Department of Pharmacology and Graduate Programs in Neuroscience, University of Minnesota, Minneapolis, MN 55455, United States.
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Wang XF, Lin X, Li DY, Zhou R, Greenbaum J, Chen YC, Zeng CP, Peng LP, Wu KH, Ao ZX, Lu JM, Guo YF, Shen J, Deng HW. Linking Alzheimer's disease and type 2 diabetes: Novel shared susceptibility genes detected by cFDR approach. J Neurol Sci 2017; 380:262-272. [PMID: 28870582 DOI: 10.1016/j.jns.2017.07.044] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 06/29/2017] [Accepted: 07/28/2017] [Indexed: 02/08/2023]
Abstract
BACKGROUND Both type 2 diabetes (T2D) and Alzheimer's disease (AD) occur commonly in the aging populations and T2D has been considered as an important risk factor for AD. The heritability of both diseases is estimated to be over 50%. However, common pleiotropic single-nucleotide polymorphisms (SNPs)/loci have not been well-defined. The aim of this study is to analyze two large public accessible GWAS datasets to identify novel common genetic loci for T2D and/or AD. METHODS AND MATERIALS The recently developed novel conditional false discovery rate (cFDR) approach was used to analyze the summary GWAS datasets from International Genomics of Alzheimer's Project (IGAP) and Diabetes Genetics Replication And Meta-analysis (DIAGRAM) to identify novel susceptibility genes for AD and T2D. RESULTS We identified 78 SNPs (including 58 novel SNPs) that were associated with AD in Europeans conditional on T2D (cFDR<0.05). 66 T2D SNPs (including 40 novel SNPs) were identified by conditioning on SNPs association with AD (cFDR<0.05). A conjunction-cFDR (ccFDR) analysis detected 8 pleiotropic SNPs with a significance threshold of ccFDR<0.05 for both AD and T2D, of which 5 SNPs (rs6982393, rs4734295, rs7812465, rs10510109, rs2421016) were novel findings. Furthermore, among the 8 SNPs annotated at 6 different genes, 3 corresponding genes TP53INP1, TOMM40 and C8orf38 were related to mitochondrial dysfunction, critically involved in oxidative stress, which potentially contribute to the etiology of both AD and T2D. CONCLUSION Our study provided evidence for shared genetic loci between T2D and AD in European subjects by using cFDR and ccFDR analyses. These results may provide novel insight into the etiology and potential therapeutic targets of T2D and/or AD.
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Affiliation(s)
- Xia-Fang Wang
- Department of Endocrinology and Metabolism, The Third Affiliated Hospital of Southern Medical University, Guangzhou 510630, PR China
| | - Xu Lin
- Department of Endocrinology and Metabolism, The Third Affiliated Hospital of Southern Medical University, Guangzhou 510630, PR China
| | - Ding-You Li
- Department of Gastroenterology, Children's Mercy Kansas City, University of Missouri Kansas City School of Medicine, Kansas City MO 64108, USA
| | - Rou Zhou
- Department of Endocrinology and Metabolism, The Third Affiliated Hospital of Southern Medical University, Guangzhou 510630, PR China
| | - Jonathan Greenbaum
- Center for Bioinformatics and Genomics, Department of Global Biostatistics and Data Science, School of Public Health and Tropical Medicine, Tulane University, New Orleans, LA 70112, USA
| | - Yuan-Cheng Chen
- Department of Endocrinology and Metabolism, The Third Affiliated Hospital of Southern Medical University, Guangzhou 510630, PR China
| | - Chun-Ping Zeng
- Department of Endocrinology and Metabolism, The Third Affiliated Hospital of Southern Medical University, Guangzhou 510630, PR China
| | - Lin-Ping Peng
- Department of Endocrinology and Metabolism, The Third Affiliated Hospital of Southern Medical University, Guangzhou 510630, PR China
| | - Ke-Hao Wu
- Center for Bioinformatics and Genomics, Department of Global Biostatistics and Data Science, School of Public Health and Tropical Medicine, Tulane University, New Orleans, LA 70112, USA
| | - Zeng-Xin Ao
- Department of Endocrinology and Metabolism, The Third Affiliated Hospital of Southern Medical University, Guangzhou 510630, PR China
| | - Jun-Min Lu
- Department of Endocrinology and Metabolism, The Third Affiliated Hospital of Southern Medical University, Guangzhou 510630, PR China
| | - Yan-Fang Guo
- Institute of Bioinformatics, School of Basic Medical Science, Southern Medical University, Guangzhou, Guangdong 510515, PR China
| | - Jie Shen
- Department of Endocrinology and Metabolism, The Third Affiliated Hospital of Southern Medical University, Guangzhou 510630, PR China
| | - Hong-Wen Deng
- Department of Endocrinology and Metabolism, The Third Affiliated Hospital of Southern Medical University, Guangzhou 510630, PR China; Center for Bioinformatics and Genomics, Department of Global Biostatistics and Data Science, School of Public Health and Tropical Medicine, Tulane University, New Orleans, LA 70112, USA.
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Cheng S, Wani WY, Hottman DA, Jeong A, Cao D, LeBlanc KJ, Saftig P, Zhang J, Li L. Haplodeficiency of Cathepsin D does not affect cerebral amyloidosis and autophagy in APP/PS1 transgenic mice. J Neurochem 2017; 142:297-304. [PMID: 28429406 DOI: 10.1111/jnc.14048] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Revised: 03/06/2017] [Accepted: 04/07/2017] [Indexed: 01/05/2023]
Abstract
Autophagy and lysosomal function are important for protein homeostasis and their dysfunction have been associated with Alzheimer's disease (AD). Increased immunoreactivities of an important lysosomal protease, cathepsin D (Cat D), are evident in amyloid plaques and neurons in patients with AD. This study tests the hypothesis that deleting one allele of the cathepsin D gene (Ctsd) impacts cerebral β-amyloidosis in amyloid-β precursor protein (APP)sw/PS1dE9 (APP/PS1) double transgenic mice. Despite a significant 38% decrease in Cat D level in APP/PS1/Ctsd+/- compared with APP/PS1/Ctsd+/+ mice, no changes in steady state levels and deposition of Aβ were found in the brain. There were also no differences in APP processing, the levels of two other Aβ-degrading proteases, the levels of autophagy related protein, such as LAMP2, P62, LC3-I, LC3-II, and Beclin-1, or the markers of neuroinflammation, observed between the APP/PS1/Ctsd+/+ and APP/PS1/Ctsd+/- mice. Our findings demonstrate that in wild-type mice, Cat D protein levels are either in excess or redundant with other factors in the brain, and at least one allele of Ctsd is dispensable for cerebral β-amyloidosis and autophagy in APP/PS1 transgenic mice.
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Affiliation(s)
- Shaowu Cheng
- Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, Minnesota, USA.,Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-Cerebral Disease, Hunan University of Chinese Medicine, Changsha, Hunan, China
| | - Willayat Y Wani
- Department of Pathology, Center for Free Radical Research and Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - David A Hottman
- Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Angela Jeong
- Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Dongfeng Cao
- Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Kyle J LeBlanc
- Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Paul Saftig
- Biochemisches Institut, CAU Kiel, Kiel, Germany
| | - Jianhua Zhang
- Department of Pathology, Center for Free Radical Research and Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Ling Li
- Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, Minnesota, USA
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Brioschi M, Martinez Fernandez A, Banfi C. Exploring the biochemistry of the prenylome and its role in disease through proteomics: progress and potential. Expert Rev Proteomics 2017; 14:515-528. [PMID: 28521569 DOI: 10.1080/14789450.2017.1332998] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
INTRODUCTION Protein prenylation is a ubiquitous covalent post-translational modification characterized by the addition of farnesyl or geranylgeranyl isoprenoid groups to a cysteine residue located near the carboxyl terminal of a protein. It is essential for the proper localization and cellular activity of numerous proteins, including Ras family GTPases and G-proteins. In addition to its roles in cellular physiology, the prenylation process has important implications in human diseases and in the recent years, it has become attractive target of inhibitors with therapeutic potential. Areas covered: This review attempts to summarize the basic aspects of prenylation integrating them with biological functions in diseases and giving an account of the current status of prenylation inhibitors as potential therapeutics. We also summarize the methodologies for the characterization of this modification. Expert commentary: The growing body of evidence suggesting an important role of prenylation in diseases and the subsequent development of inhibitors of the enzymes responsible for this modification lead to the urgent need to identify the full spectrum of prenylated proteins that are altered in the disease or affected by drugs. Proteomic tools to analyze prenylated proteins are recently emerging, thanks to the advancement in the field of mass spectrometry coupled to enrichment strategies.
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Wang J, Yao X, Huang J. New tricks for human farnesyltransferase inhibitor: cancer and beyond. MEDCHEMCOMM 2017; 8:841-854. [PMID: 30108801 PMCID: PMC6072492 DOI: 10.1039/c7md00030h] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 02/15/2017] [Indexed: 12/18/2022]
Abstract
Human protein farnesyltransferase (FTase) catalyzes the addition of a C15-farnesyl lipid group to the cysteine residue located in the COOH-terminal tetrapeptide motif of a variety of important substrate proteins, including well-known Ras protein superfamily. The farnesylation of Ras protein is required both for its normal physiological function, and for the transforming capacity of its oncogenic mutants. Over the last several decades, FTase inhibitors (FTIs) were developed to disrupt the farnesylation of oncogenic Ras as anti-cancer agents, and some of them have entered cancer clinical investigation. On the other hand, some substrates of FTase were demonstrated to be related with other human diseases, including Hutchinson-Gilford progeria syndrome, chronic hepatitis D, and cardiovascular diseases. In this review, we summarize the roles of FTase in malignant transformation, proliferation, apoptosis, angiogenesis, and metastasis of tumor cells, and the recently anticancer clinical research advances of FTIs. The therapeutic prospect of FTIs on several other human diseases is also discussed.
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Affiliation(s)
- Jingyuan Wang
- Shanghai Key Laboratory of New Drug Design , School of Pharmacy , East China University of Science and Technology , 130 Mei Long Road , Shanghai 200237 , China . ; Tel: (+86)21 64253681
| | - Xue Yao
- Shanghai Key Laboratory of New Drug Design , School of Pharmacy , East China University of Science and Technology , 130 Mei Long Road , Shanghai 200237 , China . ; Tel: (+86)21 64253681
| | - Jin Huang
- Shanghai Key Laboratory of New Drug Design , School of Pharmacy , East China University of Science and Technology , 130 Mei Long Road , Shanghai 200237 , China . ; Tel: (+86)21 64253681
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Gao S, Mo J, Chen L, Wang Y, Mao X, Shi Y, Zhang X, Yu R, Zhou X. Astrocyte GGTI-mediated Rac1 prenylation upregulates NF-κB expression and promotes neuronal apoptosis following hypoxia/ischemia. Neuropharmacology 2016; 103:44-56. [DOI: 10.1016/j.neuropharm.2015.12.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 11/20/2015] [Accepted: 12/07/2015] [Indexed: 12/14/2022]
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McGinley LM, Sims E, Lunn JS, Kashlan ON, Chen KS, Bruno ES, Pacut CM, Hazel T, Johe K, Sakowski SA, Feldman EL. Human Cortical Neural Stem Cells Expressing Insulin-Like Growth Factor-I: A Novel Cellular Therapy for Alzheimer's Disease. Stem Cells Transl Med 2016; 5:379-91. [PMID: 26744412 PMCID: PMC4807660 DOI: 10.5966/sctm.2015-0103] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 11/19/2015] [Indexed: 01/05/2023] Open
Abstract
Alzheimer's disease (AD) is the most prevalent age-related neurodegenerative disorder and a leading cause of dementia. Current treatment fails to modify underlying disease pathologies and very little progress has been made to develop effective drug treatments. Cellular therapies impact disease by multiple mechanisms, providing increased efficacy compared with traditional single-target approaches. In amyotrophic lateral sclerosis, we have shown that transplanted spinal neural stem cells (NSCs) integrate into the spinal cord, form synapses with the host, improve inflammation, and reduce disease-associated pathologies. Our current goal is to develop a similar "best in class" cellular therapy for AD. Here, we characterize a novel human cortex-derived NSC line modified to express insulin-like growth factor-I (IGF-I), HK532-IGF-I. Because IGF-I promotes neurogenesis and synaptogenesis in vivo, this enhanced NSC line offers additional environmental enrichment, enhanced neuroprotection, and a multifaceted approach to treating complex AD pathologies. We show that autocrine IGF-I production does not impact the cell secretome or normal cellular functions, including proliferation, migration, or maintenance of progenitor status. However, HK532-IGF-I cells preferentially differentiate into gamma-aminobutyric acid-ergic neurons, a subtype dysregulated in AD; produce increased vascular endothelial growth factor levels; and display an increased neuroprotective capacity in vitro. We also demonstrate that HK532-IGF-I cells survive peri-hippocampal transplantation in a murine AD model and exhibit long-term persistence in targeted brain areas. In conclusion, we believe that harnessing the benefits of cellular and IGF-I therapies together will provide the optimal therapeutic benefit to patients, and our findings support further preclinical development of HK532-IGF-I cells into a disease-modifying intervention for AD.
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Affiliation(s)
- Lisa M McGinley
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, USA
| | - Erika Sims
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, USA
| | - J Simon Lunn
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, USA
| | - Osama N Kashlan
- Department of Neurosurgery, University of Michigan, Ann Arbor, Michigan, USA
| | - Kevin S Chen
- Department of Neurosurgery, University of Michigan, Ann Arbor, Michigan, USA
| | - Elizabeth S Bruno
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, USA
| | - Crystal M Pacut
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, USA
| | - Tom Hazel
- Neuralstem, Inc., Germantown, Maryland, USA
| | - Karl Johe
- Neuralstem, Inc., Germantown, Maryland, USA
| | - Stacey A Sakowski
- A. Alfred Taubman Medical Research Institute, University of Michigan, Ann Arbor, Michigan, USA
| | - Eva L Feldman
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, USA A. Alfred Taubman Medical Research Institute, University of Michigan, Ann Arbor, Michigan, USA
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Gao S, Yu R, Zhou X. The Role of Geranylgeranyltransferase I-Mediated Protein Prenylation in the Brain. Mol Neurobiol 2015; 53:6925-6937. [DOI: 10.1007/s12035-015-9594-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 12/01/2015] [Indexed: 10/22/2022]
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Xia W, Mo H. Potential of tocotrienols in the prevention and therapy of Alzheimer's disease. J Nutr Biochem 2015; 31:1-9. [PMID: 27133418 DOI: 10.1016/j.jnutbio.2015.10.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 10/19/2015] [Accepted: 10/23/2015] [Indexed: 02/07/2023]
Abstract
Currently there is no cure for Alzheimer's disease (AD); clinical trials are underway to reduce amyloid generation and deposition, a neuropathological hallmark in brains of AD patients. While genetic factors and neuroinflammation contribute significantly to AD pathogenesis, whether increased cholesterol level is a causative factor or a result of AD is equivocal. Prenylation of proteins regulating neuronal functions requires mevalonate-derived farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP). The observation that the levels of FPP and GGPP, but not that of cholesterol, are elevated in AD patients is consistent with the finding that statins, competitive inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase, reduce FPP and GGPP levels and amyloid β protein production in preclinical studies. Retrospective studies show inverse correlations between incidence of AD and the intake and serum levels of the HMG CoA reductase-suppressive tocotrienols; tocopherols show mixed results. Tocotrienols, but not tocopherols, block the processing and nuclear localization of sterol regulatory element binding protein-2, the transcriptional factor for HMG CoA reductase and FPP synthase, and enhance the degradation of HMG CoA reductase. Consequently, tocotrienols deplete the pool of FPP and GGPP and potentially blunt prenylation-dependent AD pathogenesis. The antiinflammatory activity of tocotrienols further contributes to their protection against AD. The mevalonate- and inflammation-suppressive activities of tocotrienols may represent those of an estimated 23,000 mevalonate-derived plant secondary metabolites called isoprenoids, many of which are neuroprotective. Tocotrienol-containing plant foods and tocotrienol derivatives and formulations with enhanced bioavailability may offer a novel approach in AD prevention and treatment.
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Affiliation(s)
- Weiming Xia
- Geriatric Research Education and Clinical Center, ENR Memorial Veterans Hospital, Bedford, MA.
| | - Huanbiao Mo
- Department of Nutrition, Byrdine F. Lewis School of Nursing and Health Professions, Georgia State University, Atlanta, GA; Center for Obesity Reversal, Georgia State University, Atlanta, GA.
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Cheng S, LeBlanc KJ, Li L. Triptolide preserves cognitive function and reduces neuropathology in a mouse model of Alzheimer's disease. PLoS One 2014; 9:e108845. [PMID: 25275487 PMCID: PMC4183525 DOI: 10.1371/journal.pone.0108845] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Accepted: 09/02/2014] [Indexed: 12/02/2022] Open
Abstract
Triptolide, a major bioactive ingredient of a widely used herbal medicine, has been shown to possess multiple pharmacological functions, including potential neuroprotective effects pertinent to Alzheimer's disease (AD) in vitro. However, the therapeutic potential of triptolide for AD in vivo has not been thoroughly evaluated. In the present study, we investigated the impact of peripherally administered triptolide on AD-related behavior and neuropathology in APPswe/PS1ΔE9 (APP/PS1) mice, an established model of AD. Our results showed that two-month treatment with triptolide rescued cognitive function in APP/PS1 mice. Immunohistochemical analyses indicated that triptolide treatment led to a significant decrease in amyloid-β (Aβ) deposition and neuroinflammation in treated mice. In contrast to previous findings in vitro, biochemical analyses showed that triptolide treatment did not significantly affect the production pathway of Aβ in vivo. Intriguingly, further analyses revealed that triptolide treatment upregulated the level of insulin-degrading enzyme, a major Aβ-degrading enzyme in the brain, indicating that triptolide treatment reduced Aβ pathology by enhancing the proteolytic degradation of Aβ. Our findings demonstrate that triptolide treatment ameliorates key behavioral and neuropathological changes found in AD, suggesting that triptolide may serve as a potential therapeutic agent for AD.
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Affiliation(s)
- Shaowu Cheng
- Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Kyle J. LeBlanc
- Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Ling Li
- Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, Minnesota, United States of America
- * E-mail:
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Afshordel S, Wood WG, Igbavboa U, Muller WE, Eckert GP. Impaired geranylgeranyltransferase-I regulation reduces membrane-associated Rho protein levels in aged mouse brain. J Neurochem 2014; 129:732-42. [PMID: 24428713 PMCID: PMC3999261 DOI: 10.1111/jnc.12654] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Revised: 01/09/2014] [Accepted: 01/10/2014] [Indexed: 12/21/2022]
Abstract
Synaptic impairment rather than neuronal loss may be the leading cause of cognitive dysfunction in brain aging. Certain small Rho-GTPases are involved in synaptic plasticity, and their dysfunction is associated with brain aging and neurodegeneration. Rho-GTPases undergo prenylation by attachment of geranylgeranylpyrophosphate (GGPP) catalyzed by GGTase-I. We examined age-related changes in the abundance of Rho and Rab proteins in membrane and cytosolic fractions as well as of GGTase-I in brain tissue of 3- and 23-month-old C57BL/6 mice. We report a shift in the cellular localization of Rho-GTPases toward reduced levels of membrane-associated and enhanced cytosolic levels of those proteins in aged mouse brain as compared with younger mice. The age-related reduction in membrane-associated Rho proteins was associated with a reduction in GGTase-Iβ levels that regulates binding of GGPP to Rho-GTPases. Proteins prenylated by GGTase-II were not reduced in aged brain indicating a specific targeting of GGTase-I in the aged brain. Inhibition of GGTase-I in vitro modeled the effects of aging we observed in vivo. We demonstrate for the first time a decrease in membrane-associated Rho proteins in aged brain in association with down-regulation of GGTase-Iβ. This down-regulation could be one of the mechanisms causing age-related weakening of synaptic plasticity.
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Affiliation(s)
- Sarah Afshordel
- Department of Pharmacology, Biocenter Niederursel, University of Frankfurt, Max-von-Laue-St. 9, 60438 Frankfurt, Germany
| | - W. Gibson Wood
- Department of Pharmacology, University of Minnesota School of Medicine, Geriatric Research, Education and Clinical Center, VAMC, Minneapolis, MN 55417 USA
| | - Urule Igbavboa
- Department of Pharmacology, University of Minnesota School of Medicine, Geriatric Research, Education and Clinical Center, VAMC, Minneapolis, MN 55417 USA
| | - Walter E. Muller
- Department of Pharmacology, Biocenter Niederursel, University of Frankfurt, Max-von-Laue-St. 9, 60438 Frankfurt, Germany
| | - Gunter P. Eckert
- Department of Pharmacology, Biocenter Niederursel, University of Frankfurt, Max-von-Laue-St. 9, 60438 Frankfurt, Germany
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Parent MALT, Hottman DA, Cheng S, Zhang W, McMahon LL, Yuan LL, Li L. Simvastatin treatment enhances NMDAR-mediated synaptic transmission by upregulating the surface distribution of the GluN2B subunit. Cell Mol Neurobiol 2014; 34:693-705. [PMID: 24687455 DOI: 10.1007/s10571-014-0051-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Accepted: 03/18/2014] [Indexed: 10/25/2022]
Abstract
The ramifications of statins on plasma cholesterol and coronary heart disease have been well documented. However, there is increasing evidence that inhibition of the mevalonate pathway may provide independent neuroprotective and procognitive pleiotropic effects, most likely via inhibition of isoprenoids, mainly farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP). FPP and GGPP are the major donors of prenyl groups for protein prenylation. Modulation of isoprenoid availability impacts a slew of cellular processes including synaptic plasticity in the hippocampus. Our previous work has demonstrated that simvastatin (SV) administration improves hippocampus-dependent spatial memory, rescuing memory deficits in a mouse model of Alzheimer's disease. Treatment of hippocampal slices with SV enhances long-term potentiation (LTP), and this effect is dependent on the activation of Akt (protein kinase B). Further studies showed that SV-induced enhancement of hippocampal LTP is driven by depletion of FPP and inhibition of farnesylation. In the present study, we report the functional consequences of exposure to SV at cellular/synaptic and molecular levels. While application of SV has no effect on intrinsic membrane properties of CA1 pyramidal neurons, including hyperpolarization-activated cyclic-nucleotide channel-mediated sag potentials, the afterhyperpolarization (AHP), and excitability, SV application potentiates the N-methyl D-aspartate receptor (NMDAR)-mediated contribution to synaptic transmission. In mouse hippocampal slices and human neuronal cells, SV treatment increases the surface distribution of the GluN2B subunit of the NMDAR without affecting cellular cholesterol content. We conclude that SV-induced enhancement of synaptic plasticity in the hippocampus is likely mediated by augmentation of synaptic NMDAR components that are largely responsible for driving synaptic plasticity in the CA1 region.
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Affiliation(s)
- Marc-Alexander L T Parent
- Department of Experimental and Clinical Pharmacology, University of Minnesota, McGuire Translational Research Facility, 2001 6th St SE, Minneapolis, MN, 55455, USA
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Inhibiting geranylgeranylation increases neurite branching and differentially activates cofilin in cell bodies and growth cones. Mol Neurobiol 2014; 50:49-59. [PMID: 24515839 DOI: 10.1007/s12035-014-8653-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Accepted: 01/23/2014] [Indexed: 10/25/2022]
Abstract
Inhibitors of the mevalonate pathway, including the highly prescribed statins, reduce the production of cholesterol and isoprenoids such as geranylgeranyl pyrophosphates. The Rho family of small guanine triphosphatases (GTPases) requires isoprenylation, specifically geranylgeranylation, for activation. Because Rho GTPases are primary regulators of actin filament rearrangements required for process extension, neurite arborization, and synaptic plasticity, statins may affect cognition or recovery from nervous system injury. Here, we assessed how manipulating geranylgeranylation affects neurite initiation, elongation, and branching in neuroblastoma growth cones. Treatment with the statin, lovastatin (20 μM), decreased measures of neurite initiation by 17.0 to 19.0 % when a source of cholesterol was present and increased neurite branching by 4.03- to 9.54-fold (regardless of exogenous cholesterol). Neurite elongation was increased by treatment with lovastatin only in cholesterol-free culture conditions. Treatment with lovastatin decreased growth cone actin filament content by up to 24.3 %. In all cases, co-treatment with the prenylation precursor, geranylgeraniol (10 μM), reversed the effect of lovastatin. In a prior work, statin effects on outgrowth were linked to modulating the actin depolymerizing factor, cofilin. In our assays, treatment with lovastatin or geranylgeraniol decreased cofilin phosphorylation in whole cell lysates. However, lovastatin increased cofilin phosphorylation in cell bodies and decreased it in growth cones, indicating differential regulation in specific cell regions. Together, we interpret these data to suggest that protein geranylgeranylation likely regulates growth cone actin filament content and subsequent neurite outgrowth through mechanisms that also affect actin nucleation and polymerization.
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Hottman DA, Li L. Protein prenylation and synaptic plasticity: implications for Alzheimer's disease. Mol Neurobiol 2014; 50:177-85. [PMID: 24390573 DOI: 10.1007/s12035-013-8627-z] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Accepted: 12/20/2013] [Indexed: 12/11/2022]
Abstract
Protein prenylation is an important lipid posttranslational modification of proteins. It includes protein farnesylation and geranylgeranylation, in which the 15-carbon farnesyl pyrophosphate or 20-carbon geranylgeranyl pyrophosphate is attached to the C-terminus of target proteins, catalyzed by farnesyl transferase or geranylgeranyl transferases, respectively. Protein prenylation facilitates the anchoring of proteins into the cell membrane and mediates protein-protein interactions. Among numerous proteins that undergo prenylation, small GTPases represent the largest group of prenylated proteins. Small GTPases are involved in regulating a plethora of cellular functions including synaptic plasticity. The prenylation status of small GTPases determines the subcellular locations and functions of the proteins. Dysregulation or dysfunction of small GTPases leads to the development of different types of disorders. Emerging evidence indicates that prenylated proteins, in particular small GTPases, may play important roles in the pathogenesis of Alzheimer's disease. This review focuses on the prenylation of Ras and Rho subfamilies of small GTPases and its relation to synaptic plasticity and Alzheimer's disease.
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Affiliation(s)
- David A Hottman
- Department of Experimental and Clinical Pharmacology, University of Minnesota, 2001 6th St SE, MTRF 4-208, Minneapolis, MN, 55455, USA
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