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Theiss EL, Griebsch LV, Lauer AA, Janitschke D, Erhardt VKJ, Haas EC, Kuppler KN, Radermacher J, Walzer O, Portius D, Grimm HS, Hartmann T, Grimm MOW. Vitamin B12 Attenuates Changes in Phospholipid Levels Related to Oxidative Stress in SH-SY5Y Cells. Cells 2022; 11:cells11162574. [PMID: 36010649 PMCID: PMC9406929 DOI: 10.3390/cells11162574] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 02/18/2022] [Accepted: 08/15/2022] [Indexed: 01/04/2023] Open
Abstract
Oxidative stress is closely linked to Alzheimer’s disease (AD), and is detected peripherally as well as in AD-vulnerable brain regions. Oxidative stress results from an imbalance between the generation and degradation of reactive oxidative species (ROS), leading to the oxidation of proteins, nucleic acids, and lipids. Extensive lipid changes have been found in post mortem AD brain tissue; these changes include the levels of total phospholipids, sphingomyelin, and ceramide, as well as plasmalogens, which are highly susceptible to oxidation because of their vinyl ether bond at the sn-1 position of the glycerol-backbone. Several lines of evidence indicate that a deficiency in the neurotropic vitamin B12 is linked with AD. In the present study, treatment of the neuroblastoma cell line SH-SY5Y with vitamin B12 resulted in elevated levels of phosphatidylcholine, phosphatidylethanolamine, sphingomyelin, and plasmalogens. Vitamin B12 also protected plasmalogens from hydrogen peroxide (H2O2)-induced oxidative stress due to an elevated expression of the ROS-degrading enzymes superoxide-dismutase (SOD) and catalase (CAT). Furthermore, vitamin B12 elevates plasmalogen synthesis by increasing the expression of alkylglycerone phosphate synthase (AGPS) and choline phosphotransferase 1 (CHPT1) in SH-SY5Y cells exposed to H2O2-induced oxidative stress.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Oliver Walzer
- Experimental Neurology, Saarland University, 66424 Homburg, Germany
| | - Dorothea Portius
- Nutrition Therapy and Counseling, Campus Gera, SRH University of Applied Health Science, 07548 Gera, Germany
| | | | - Tobias Hartmann
- Experimental Neurology, Saarland University, 66424 Homburg, Germany
- Deutsches Institut für DemenzPrävention, Saarland University, 66424 Homburg, Germany
| | - Marcus Otto Walter Grimm
- Experimental Neurology, Saarland University, 66424 Homburg, Germany
- Deutsches Institut für DemenzPrävention, Saarland University, 66424 Homburg, Germany
- Nutrition Therapy and Counseling, Campus Rheinland, SRH University of Applied Health Sciences, 51377 Leverkusen, Germany
- Correspondence: or
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Lauer AA, Grimm HS, Apel B, Golobrodska N, Kruse L, Ratanski E, Schulten N, Schwarze L, Slawik T, Sperlich S, Vohla A, Grimm MOW. Mechanistic Link between Vitamin B12 and Alzheimer's Disease. Biomolecules 2022; 12:129. [PMID: 35053277 PMCID: PMC8774227 DOI: 10.3390/biom12010129] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 01/10/2022] [Accepted: 01/11/2022] [Indexed: 01/27/2023] Open
Abstract
Alzheimer's disease (AD) is the most common form of dementia in the elderly population, affecting over 55 million people worldwide. Histopathological hallmarks of this multifactorial disease are an increased plaque burden and tangles in the brains of affected individuals. Several lines of evidence indicate that B12 hypovitaminosis is linked to AD. In this review, the biochemical pathways involved in AD that are affected by vitamin B12, focusing on APP processing, Aβ fibrillization, Aβ-induced oxidative damage as well as tau hyperphosphorylation and tau aggregation, are summarized. Besides the mechanistic link, an overview of clinical studies utilizing vitamin B supplementation are given, and a potential link between diseases and medication resulting in a reduced vitamin B12 level and AD are discussed. Besides the disease-mediated B12 hypovitaminosis, the reduction in vitamin B12 levels caused by an increasing change in dietary preferences has been gaining in relevance. In particular, vegetarian and vegan diets are associated with vitamin B12 deficiency, and therefore might have potential implications for AD. In conclusion, our review emphasizes the important role of vitamin B12 in AD, which is particularly important, as even in industrialized countries a large proportion of the population might not be sufficiently supplied with vitamin B12.
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Affiliation(s)
- Anna Andrea Lauer
- Experimental Neurology, Saarland University, 66424 Homburg, Germany; (A.A.L.); (H.S.G.)
| | - Heike Sabine Grimm
- Experimental Neurology, Saarland University, 66424 Homburg, Germany; (A.A.L.); (H.S.G.)
| | - Birgit Apel
- Nutrition Therapy and Counseling, Campus Rheinland, SRH University of Applied Health Sciences, 51377 Leverkusen, Germany; (B.A.); (N.G.); (L.K.); (E.R.); (N.S.); (L.S.); (T.S.); (S.S.); (A.V.)
| | - Nataliya Golobrodska
- Nutrition Therapy and Counseling, Campus Rheinland, SRH University of Applied Health Sciences, 51377 Leverkusen, Germany; (B.A.); (N.G.); (L.K.); (E.R.); (N.S.); (L.S.); (T.S.); (S.S.); (A.V.)
| | - Lara Kruse
- Nutrition Therapy and Counseling, Campus Rheinland, SRH University of Applied Health Sciences, 51377 Leverkusen, Germany; (B.A.); (N.G.); (L.K.); (E.R.); (N.S.); (L.S.); (T.S.); (S.S.); (A.V.)
| | - Elina Ratanski
- Nutrition Therapy and Counseling, Campus Rheinland, SRH University of Applied Health Sciences, 51377 Leverkusen, Germany; (B.A.); (N.G.); (L.K.); (E.R.); (N.S.); (L.S.); (T.S.); (S.S.); (A.V.)
| | - Noemi Schulten
- Nutrition Therapy and Counseling, Campus Rheinland, SRH University of Applied Health Sciences, 51377 Leverkusen, Germany; (B.A.); (N.G.); (L.K.); (E.R.); (N.S.); (L.S.); (T.S.); (S.S.); (A.V.)
| | - Laura Schwarze
- Nutrition Therapy and Counseling, Campus Rheinland, SRH University of Applied Health Sciences, 51377 Leverkusen, Germany; (B.A.); (N.G.); (L.K.); (E.R.); (N.S.); (L.S.); (T.S.); (S.S.); (A.V.)
| | - Thomas Slawik
- Nutrition Therapy and Counseling, Campus Rheinland, SRH University of Applied Health Sciences, 51377 Leverkusen, Germany; (B.A.); (N.G.); (L.K.); (E.R.); (N.S.); (L.S.); (T.S.); (S.S.); (A.V.)
| | - Saskia Sperlich
- Nutrition Therapy and Counseling, Campus Rheinland, SRH University of Applied Health Sciences, 51377 Leverkusen, Germany; (B.A.); (N.G.); (L.K.); (E.R.); (N.S.); (L.S.); (T.S.); (S.S.); (A.V.)
| | - Antonia Vohla
- Nutrition Therapy and Counseling, Campus Rheinland, SRH University of Applied Health Sciences, 51377 Leverkusen, Germany; (B.A.); (N.G.); (L.K.); (E.R.); (N.S.); (L.S.); (T.S.); (S.S.); (A.V.)
| | - Marcus Otto Walter Grimm
- Experimental Neurology, Saarland University, 66424 Homburg, Germany; (A.A.L.); (H.S.G.)
- Nutrition Therapy and Counseling, Campus Rheinland, SRH University of Applied Health Sciences, 51377 Leverkusen, Germany; (B.A.); (N.G.); (L.K.); (E.R.); (N.S.); (L.S.); (T.S.); (S.S.); (A.V.)
- Deutsches Institut für DemenzPrävention, Saarland University, 66424 Homburg, Germany
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Kurokin I, Lauer AA, Janitschke D, Winkler J, Theiss EL, Griebsch LV, Pilz SM, Matschke V, van der Laan M, Grimm HS, Hartmann T, Grimm MOW. Targeted Lipidomics of Mitochondria in a Cellular Alzheimer's Disease Model. Biomedicines 2021; 9:1062. [PMID: 34440266 PMCID: PMC8393816 DOI: 10.3390/biomedicines9081062] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/12/2021] [Accepted: 08/17/2021] [Indexed: 01/12/2023] Open
Abstract
Alzheimer's disease (AD) is neuropathologically characterized by the accumulation of Amyloid-β (Aβ) in senile plaques derived from amyloidogenic processing of a precursor protein (APP). Recently, changes in mitochondrial function have become in the focus of the disease. Whereas a link between AD and lipid-homeostasis exists, little is known about potential alterations in the lipid composition of mitochondria. Here, we investigate potential changes in the main mitochondrial phospholipid classes phosphatidylcholine, phosphatidylethanolamine and the corresponding plasmalogens and lyso-phospholipids of a cellular AD-model (SH-SY5Y APPswedish transfected cells), comparing these results with changes in cell-homogenates. Targeted shotgun-lipidomics revealed lipid alterations to be specific for mitochondria and cannot be predicted from total cell analysis. In particular, lipids containing three and four times unsaturated fatty acids (FA X:4), such as arachidonic-acid, are increased, whereas FA X:6 or X:5, such as eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA), are decreased. Additionally, PE plasmalogens are increased in contrast to homogenates. Results were confirmed in another cellular AD model, having a lower affinity to amyloidogenic APP processing. Besides several similarities, differences in particular in PE species exist, demonstrating that differences in APP processing might lead to specific changes in lipid homeostasis in mitochondria. Importantly, the observed lipid alterations are accompanied by changes in the carnitine carrier system, also suggesting an altered mitochondrial functionality.
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Affiliation(s)
- Irina Kurokin
- Experimental Neurology, Saarland University, 66421 Homburg, Germany; (I.K.); (A.A.L.); (D.J.); (J.W.); (E.L.T.); (L.V.G.); (S.M.P.); (H.S.G.)
| | - Anna Andrea Lauer
- Experimental Neurology, Saarland University, 66421 Homburg, Germany; (I.K.); (A.A.L.); (D.J.); (J.W.); (E.L.T.); (L.V.G.); (S.M.P.); (H.S.G.)
| | - Daniel Janitschke
- Experimental Neurology, Saarland University, 66421 Homburg, Germany; (I.K.); (A.A.L.); (D.J.); (J.W.); (E.L.T.); (L.V.G.); (S.M.P.); (H.S.G.)
| | - Jakob Winkler
- Experimental Neurology, Saarland University, 66421 Homburg, Germany; (I.K.); (A.A.L.); (D.J.); (J.W.); (E.L.T.); (L.V.G.); (S.M.P.); (H.S.G.)
| | - Elena Leoni Theiss
- Experimental Neurology, Saarland University, 66421 Homburg, Germany; (I.K.); (A.A.L.); (D.J.); (J.W.); (E.L.T.); (L.V.G.); (S.M.P.); (H.S.G.)
| | - Lea Victoria Griebsch
- Experimental Neurology, Saarland University, 66421 Homburg, Germany; (I.K.); (A.A.L.); (D.J.); (J.W.); (E.L.T.); (L.V.G.); (S.M.P.); (H.S.G.)
| | - Sabrina Melanie Pilz
- Experimental Neurology, Saarland University, 66421 Homburg, Germany; (I.K.); (A.A.L.); (D.J.); (J.W.); (E.L.T.); (L.V.G.); (S.M.P.); (H.S.G.)
| | - Veronika Matschke
- Department of Cytology, Institute of Anatomy, Medical Faculty, Ruhr University Bochum, D-44801 Bochum, Germany;
| | - Martin van der Laan
- Medical Biochemistry & Molecular Biology, Center for Molecular Signaling PZMS, Saarland University Medical School, 66421 Homburg, Germany;
| | - Heike Sabine Grimm
- Experimental Neurology, Saarland University, 66421 Homburg, Germany; (I.K.); (A.A.L.); (D.J.); (J.W.); (E.L.T.); (L.V.G.); (S.M.P.); (H.S.G.)
| | - Tobias Hartmann
- Deutsches Institut für Demenzprävention, Saarland University, 66421 Homburg, Germany;
| | - Marcus Otto Walter Grimm
- Experimental Neurology, Saarland University, 66421 Homburg, Germany; (I.K.); (A.A.L.); (D.J.); (J.W.); (E.L.T.); (L.V.G.); (S.M.P.); (H.S.G.)
- Deutsches Institut für Demenzprävention, Saarland University, 66421 Homburg, Germany;
- Nutrition Therapy and Counseling, Campus Rheinland, SRH University of Applied Health Sciences, 51377 Leverkusen, Germany
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Grimm MOW, Blümel T, Lauer AA, Janitschke D, Stahlmann C, Mett J, Haupenthal VJ, Miederer AM, Niemeyer BA, Grimm HS, Hartmann T. The impact of capsaicinoids on APP processing in Alzheimer's disease in SH-SY5Y cells. Sci Rep 2020; 10:9164. [PMID: 32514053 PMCID: PMC7280252 DOI: 10.1038/s41598-020-66009-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 05/11/2020] [Indexed: 11/08/2022] Open
Abstract
The vanilloid capsaicin is a widely consumed spice, known for its burning and "hot" sensation through activation of TRPV1 ion-channels, but also known to decrease oxidative stress, inflammation and influence tau-pathology. Beside these positive effects, little is known about its effects on amyloid-precursor-protein (APP) processing leading to amyloid-β (Aβ), the major component of senile plaques. Treatment of neuroblastoma cells with capsaicinoids (24 hours, 10 µM) resulted in enhanced Aβ-production and reduced Aβ-degradation, leading to increased Aβ-levels. In detailed analysis of the amyloidogenic-pathway, both BACE1 gene-expression as well as protein-levels were found to be elevated, leading to increased β-secretase-activity. Additionally, γ-secretase gene-expression as well as activity was enhanced, accompanied by a shift of presenilin from non-raft to raft membrane-domains where amyloidogenic processing takes place. Furthermore, impaired Aβ-degradation in presence of capsaicinoids is dependent on the insulin-degrading-enzyme, one of the major Aβ-degrading-enzymes. Regarding Aβ-homeostasis, no differences were found between the major capsaicinoids, capsaicin and dihydrocapsaicin, and a mixture of naturally derived capsaicinoids; effects on Ca2+-homeostasis were ruled out. Our results show that in respect to Alzheimer's disease, besides the known positive effects of capsaicinoids, pro-amyloidogenic properties also exist, enhancing Aβ-levels, likely restricting the potential use of capsaicinoids as therapeutic substances in Alzheimer's disease.
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Affiliation(s)
- Marcus O W Grimm
- Experimental Neurology, Saarland University, Homburg, Saar, Germany.
- Neurodegeneration and Neurobiology, Saarland University, Homburg, Saar, Germany.
| | - Tamara Blümel
- Experimental Neurology, Saarland University, Homburg, Saar, Germany
| | - Anna A Lauer
- Experimental Neurology, Saarland University, Homburg, Saar, Germany
| | | | | | - Janine Mett
- Experimental Neurology, Saarland University, Homburg, Saar, Germany
- Biosciences Zoology/Physiology-Neurobiology, Faculty NT - Natural Science and Technology, Saarland University, Saarbrücken, Germany
| | | | | | - Barbara A Niemeyer
- Molecular Biophysics, CIPMM, Saarland University, Homburg, Saar, Germany
| | - Heike S Grimm
- Experimental Neurology, Saarland University, Homburg, Saar, Germany
| | - Tobias Hartmann
- Experimental Neurology, Saarland University, Homburg, Saar, Germany
- Neurodegeneration and Neurobiology, Saarland University, Homburg, Saar, Germany
- Deutsches Institut für DemenzPrävention (DIDP), Saarland University, Homburg, Saar, Germany
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Mitochondrial dysfunction: different routes to Alzheimer's disease therapy. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2014; 2014:780179. [PMID: 25221640 PMCID: PMC4158152 DOI: 10.1155/2014/780179] [Citation(s) in RCA: 149] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Accepted: 05/29/2014] [Indexed: 01/02/2023]
Abstract
Mitochondria are dynamic ATP-generating organelle which contribute to many cellular functions including bioenergetics processes, intracellular calcium regulation, alteration of reduction-oxidation potential of cells, free radical scavenging, and activation of caspase mediated cell death. Mitochondrial functions can be negatively affected by amyloid β peptide (Aβ), an important component in Alzheimer's disease (AD) pathogenesis, and Aβ can interact with mitochondria and cause mitochondrial dysfunction. One of the most accepted hypotheses for AD onset implicates that mitochondrial dysfunction and oxidative stress are one of the primary events in the insurgence of the pathology. Here, we examine structural and functional mitochondrial changes in presence of Aβ. In particular we review data concerning Aβ import into mitochondrion and its involvement in mitochondrial oxidative stress, bioenergetics, biogenesis, trafficking, mitochondrial permeability transition pore (mPTP) formation, and mitochondrial protein interaction. Moreover, the development of AD therapy targeting mitochondria is also discussed.
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The impact of cholesterol, DHA, and sphingolipids on Alzheimer's disease. BIOMED RESEARCH INTERNATIONAL 2014; 2013:814390. [PMID: 24575399 PMCID: PMC3929518 DOI: 10.1155/2013/814390] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Accepted: 07/13/2013] [Indexed: 12/14/2022]
Abstract
Alzheimer's disease (AD) is a devastating neurodegenerative disorder currently affecting over 35 million people worldwide. Pathological hallmarks of AD are massive amyloidosis, extracellular senile plaques, and intracellular neurofibrillary tangles accompanied by an excessive loss of synapses. Major constituents of senile plaques are 40–42 amino acid long peptides termed β-amyloid (Aβ). Aβ is produced by sequential proteolytic processing of the amyloid precursor protein (APP). APP processing and Aβ production have been one of the central scopes in AD research in the past. In the last years, lipids and lipid-related issues are more frequently discussed to contribute to the AD pathogenesis. This review summarizes lipid alterations found in AD postmortem brains, AD transgenic mouse models, and the current understanding of how lipids influence the molecular mechanisms leading to AD and Aβ generation, focusing especially on cholesterol, docosahexaenoic acid (DHA), and sphingolipids/glycosphingolipids.
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Grimm MOW, Mett J, Stahlmann CP, Haupenthal VJ, Zimmer VC, Hartmann T. Neprilysin and Aβ Clearance: Impact of the APP Intracellular Domain in NEP Regulation and Implications in Alzheimer's Disease. Front Aging Neurosci 2013; 5:98. [PMID: 24391587 PMCID: PMC3870290 DOI: 10.3389/fnagi.2013.00098] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Accepted: 12/09/2013] [Indexed: 12/18/2022] Open
Abstract
One of the characteristic hallmarks of Alzheimer's disease (AD) is an accumulation of amyloid β (Aβ) leading to plaque formation and toxic oligomeric Aβ complexes. Besides the de novo synthesis of Aβ caused by amyloidogenic processing of the amyloid precursor protein (APP), Aβ levels are also highly dependent on Aβ degradation. Several enzymes are described to cleave Aβ. In this review we focus on one of the most prominent Aβ degrading enzymes, the zinc-metalloprotease Neprilysin (NEP). In the first part of the review we discuss beside the general role of NEP in Aβ degradation the alterations of the enzyme observed during normal aging and the progression of AD. In vivo and cell culture experiments reveal that a decreased NEP level results in an increased Aβ level and vice versa. In a pathological situation like AD, it has been reported that NEP levels and activity are decreased and it has been suggested that certain polymorphisms in the NEP gene result in an increased risk for AD. Conversely, increasing NEP activity in AD mouse models revealed an improvement in some behavioral tests. Therefore it has been suggested that increasing NEP might be an interesting potential target to treat or to be protective for AD making it indispensable to understand the regulation of NEP. Interestingly, it is discussed that the APP intracellular domain (AICD), one of the cleavage products of APP processing, which has high similarities to Notch receptor processing, might be involved in the transcriptional regulation of NEP. However, the mechanisms of NEP regulation by AICD, which might be helpful to develop new therapeutic strategies, are up to now controversially discussed and summarized in the second part of this review. In addition, we review the impact of AICD not only in the transcriptional regulation of NEP but also of further genes.
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Affiliation(s)
- Marcus O W Grimm
- Experimental Neurology, Saarland University , Homburg, Saar , Germany ; Neurodegeneration and Neurobiology, Saarland University , Homburg, Saar , Germany ; Deutsches Institut für DemenzPrävention, Saarland University , Homburg, Saar , Germany
| | - Janine Mett
- Experimental Neurology, Saarland University , Homburg, Saar , Germany
| | | | | | - Valerie C Zimmer
- Experimental Neurology, Saarland University , Homburg, Saar , Germany
| | - Tobias Hartmann
- Experimental Neurology, Saarland University , Homburg, Saar , Germany ; Neurodegeneration and Neurobiology, Saarland University , Homburg, Saar , Germany ; Deutsches Institut für DemenzPrävention, Saarland University , Homburg, Saar , Germany
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Zitnik G, Wang L, Martin GM, Hu Q. Localizations of endogenous APP/APP-proteolytic products are consistent with microtubular transport. J Mol Neurosci 2007; 31:59-68. [PMID: 17416970 DOI: 10.1007/bf02686118] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2006] [Revised: 11/30/1999] [Accepted: 06/03/2006] [Indexed: 12/12/2022]
Abstract
Dementia of the Alzheimer type (DAT) is associated with the accumulation of beta-amyloid (A beta) peptides derived from beta-amyloid precursor protein (APP). Goldstein and coworkers have suggested that APP acts as a cargo receptor connecting post-Golgi vesicles and motor proteins. Sisodia and colleagues have suggested that APP is a passive passenger within the vesicles. Both views predict that one should be able to visualize colocalizations of APP with microtubules, the object of the present investigation. To avoid possible artifacts created by APP overexpression, we studied endogenous expression in a human neuroblastoma cell line (SK-N-SH). Using high resolution fluorescence microscopy and antibodies specific for the amino termini of APP and A beta sequences, we found that endogenous APP and A beta peptide immunoreactivities colocalized with microtubules in interphase cells. Disruption of microtubules, followed by fixation at various time points during repolymerization, allowed us to observe the sequence and timing of these colocalizations in interphase cells. In addition, to our surprise, we found that A beta immunoreactivities colocalize with the mitotic spindle, a bundle of specialized microtubules. Because of the condensed cytoplasm found in neurons, we suggest that SK-N-SH cells might be a more convenient experimental system for exploring the mechanisms that underlie these protein localizations and the pathology that might result from altered APP protein structure and function.
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Affiliation(s)
- Galynn Zitnik
- Department of Pathology, University of Washington, Seattle, WA 98195-7470, USA.
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Zinser EG, Hartmann T, Grimm MOW. Amyloid beta-protein and lipid metabolism. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2007; 1768:1991-2001. [PMID: 17418089 DOI: 10.1016/j.bbamem.2007.02.014] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2006] [Revised: 02/14/2007] [Accepted: 02/15/2007] [Indexed: 01/16/2023]
Abstract
Lipids play an important part as risk or protective factors for Alzheimer's disease. This review summarizes the current findings in which lipids influence Alzheimer's disease and introduces the molecular mechanism how these lipids are linked to amyloid production. Besides the pathological impact of amyloid in Alzheimer's disease, amyloid has a physiological function in regulating lipid homeostasis in return. The understanding of the resulting regulatory cycles between amyloid precursor protein processing and lipids provides a platform for the development of new causal therapeutic approaches for Alzheimer's disease.
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Affiliation(s)
- Eva G Zinser
- Universität des Saarlandes, Uniklinikum Homburg, Neurobiologie, Neurologie, Gebäude 90, 66421 Homburg/Saar, Germany
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Teng FYH, Tang BL. Widespread γ-secretase activity in the cell, but do we need it at the mitochondria? Biochem Biophys Res Commun 2005; 328:1-5. [PMID: 15670741 DOI: 10.1016/j.bbrc.2004.12.131] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2004] [Indexed: 12/16/2022]
Abstract
gamma-Secretase cleavage of the amyloid precursor protein already subjected to a prior beta-secretase cleavage generates beta-amyloid (Abeta) peptide fragments, which are major constituents of the amyloid plagues found in Alzheimer's disease brain tissues. gamma-Secretase activity and components of the gamma-secretase complex are found in the endoplasmic reticulum-Golgi intermediate compartment, the Golgi, the trans-Golgi network, the plasma membrane, the endosomal-lysosomal system and recently, the mitochondria. Abeta fragments have been shown to be neurotoxic, leading to mitochondrial dysfunction and enhanced apoptotic cell death. However, if Abeta fragments are indeed detrimental to neurons, the widespread presence of enzymatic activity that would result in their generation in the cell appears to make little sense. The presence of a gamma-secretase complex in the mitochondrion, an organelle that is particularly susceptible to Abeta toxicity, is even more puzzling. Emerging evidence suggests that both secreted and intracellular Abeta fragments have endogenous functions. Also, while the fibrillogenic Abeta1-42 is clearly neurotoxic, the more abundant and soluble Abeta1-40 is an antioxidant and could potentially be neuroprotective in several ways. A "physiological" amount of Abeta1-40 production by cellular gamma-secretase activity may be part of the neuron's natural counter against oxidative damage, in addition to endogenous roles in neuronal survival and modulation of synaptic transmission. In any case, whether Abeta is produced locally in the mitochondria and the function for mitochondrial Abeta, if produced, is yet unclear.
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Affiliation(s)
- Felicia Yu Hsuan Teng
- Department of Biochemistry and Programme in Neurobiology and Aging, National University of Singapore, 8 Medical Drive, Singapore 117597, Singapore
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Wilson CA, Doms RW, Lee VMY. Distinct presenilin-dependent and presenilin-independent ?-secretases are responsible for total cellular A? production. J Neurosci Res 2003; 74:361-9. [PMID: 14598312 DOI: 10.1002/jnr.10776] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
gamma-Secretase is the second of two proteolytic enzymes involved in the liberation of the beta-amyloid peptide (Abeta) from the amyloid precursor protein (APP). gamma-Secretase cleavage occurs at several intracellular sites, including the Golgi network and the endoplasmic reticulum/intermediate compartment (ER/IC) to produce multiple forms of the Abeta peptide that can be either secreted from the cell or remain intracellular. To date, most evidence has suggested that members of the presenilin protein family are required for gamma-secretase activity. Although it seems that presenilins are indeed necessary for the production of most secreted and intracellular Abeta particularly that generated in downstream organelles, it was shown recently that a presenilin-independent gamma-secretase is active in the ER/IC and is responsible for the production of a portion of intracellular Abeta42. We discuss the implications of this finding for the understanding of presenilin biology and speculate on the putative identity of the presenilin-independent cleavage activity.
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Affiliation(s)
- Christina A Wilson
- Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
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