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Abstract
COVID-19 results in increased expression of inflammatory cytokines, but inflammation-targeting clinical trials have yielded poor to mixed results. Our studies of other disorders with an inflammatory component, including Alzheimer's disease, chemobrain, Down syndrome, normal aging, and West Nile Virus infection, showed that treatment with the 'pro-inflammatory' cytokine granulocyte-macrophage colony stimulating factor (GM-CSF) in humans or mouse models alleviated clinical, behavioral, and pathological features. We proposed that human recombinant GM-CSF (sargramostim) be repurposed to promote both the innate and adaptive immune responses in COVID-19 to reduce viral load and mortality1. Here, we report the results of a placebo-controlled study of GM-CSF in human ACE2 transgenic mice inoculated intranasally with SARS-CoV2 virus, a model of COVID-19. Infection resulted in high viral titers in lungs and brains and over 85% mortality. GM-CSF treatment beginning one day after infection increased anti-viral antibody titers, lowered mean lung viral titers proportionately (p=0.0020) and increased the odds of long-term survival by up to 5.8-fold (p=0.0358), compared to placebo. These findings suggest that, as an activator of both the innate and adaptive immune systems, GM-CSF/sargramostim may be an effective COVID-19 therapy with the potential to protect from re-infection more effectively than treatment with antiviral drugs or monoclonal antibodies.
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Feed Restriction Can Alter Gait but Does not Reduce Welfare in Meat Ducks. J APPL POULTRY RES 2019. [DOI: 10.3382/japr/pfz044] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
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Low light intensity in Pekin duck breeder barns has a greater impact on the fertility of drakes than hens. Poult Sci 2018; 97:4262-4271. [DOI: 10.3382/ps/pey289] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 06/18/2018] [Indexed: 11/20/2022] Open
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Immunolesion of melanopsin neurons causes gonadal regression in Pekin drakes (Anas platyrhynchos domesticus). Gen Comp Endocrinol 2018; 256:16-22. [PMID: 28782536 DOI: 10.1016/j.ygcen.2017.08.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 07/10/2017] [Accepted: 08/03/2017] [Indexed: 02/08/2023]
Abstract
Several light sensitive receptors have been described in the avian brain that are thought to regulate the reproductive axis independently from the eyes and pineal gland. Recently, our lab has described the presence of three of these photoneuroendocrine systems in the Pekin duck: opsin, opsin 5, & melanopsin. We set out to test the hypothesis that melanopsin receptive neurons are necessary to maintain seasonal reproductive status along with growth and development in the Pekin drake. To accomplish these goals we first investigated 50-week-old Pekin drakes that were housed in the aviary at Hope College under long day length (18h lights on) conditions in floor pens. To specifically lesion melanopsin-receptive neurons, 3μl of an anti-melanopsin-saporin conjugate (MSAP, 100ng/ul) was injected into the lateral ventricle (n=10). Control drakes were injected with 3μl of equimolar unconjugated anti-melanopsin and saporin (SAP, n=10). Reproductive behaviors were analyzed weekly in a test pen with adult hens and MSAP drakes showed a significant (p<0.01) reduction in reproductive behaviors after week 2. After 5weeks, drakes were euthanized and body weights were measured, and brains, pituitaries, and testes collected and stored for analyses. Mature MSAP-treated drakes had significantly (p<0.001) reduced relative teste weights compared to SAP controls. qRT-PCR analyses of hypothalamus showed a significant reduction (p<0.001) in GnRH and melanopsin mRNA levels, but not opsin 5, vertebrate ancient opsin, or opsin 2 (rhodopsin). Immunocytochemical analyses showed a significant reduction (p<0.01) in tyrosine hydroxylase-immunoreactivity in the PMM. These data suggest that although blue light alone is not able to maintain testicular function, the blue-light sensitive melanopsin activity is critical to maintain gonadal function.
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Association of white matter hyperintensity measurements on brain MR imaging with cognitive status, medial temporal atrophy, and cardiovascular risk factors. AJNR Am J Neuroradiol 2009; 30:1870-6. [PMID: 19643919 DOI: 10.3174/ajnr.a1693] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE White matter hyperintensities (WMHs) are frequently characterized as markers of cerebrovascular disease, whereas medial temporal atrophy (MTA) is a recognized marker of Alzheimer disease (AD). Our purpose was to test the reliability of a visual rating system (VRS) in evaluating WMHs and MTA and in distinguishing healthy from cognitively impaired subjects. MATERIALS AND METHODS Subjects (n = 192) enrolled in the Florida Alzheimer's Disease Research Center were diagnosed with no cognitive impairment, nonamnestic mild cognitive impairment (na-MCI), amnestic MCI (a-MCI), or probable AD. The severity of WMHs was assessed on T2-weighted fluid-attenuated inversion recovery axial MR images, and the severity of MTA was evaluated on 1.5-mm-thick coronal MR images by using a computer-based visual rating system. Cardiovascular risk factor scores were calculated as the sum of 10 independent cardiovascular risk factors. RESULTS WMH and MTA scores were greater in subjects with probable AD, relative to those with no cognitive impairment and na-MCI. MTA scores differentiated subjects with a-MCI from those with no cognitive impairment and na-MCI. The total WMH score was significantly related to MTA (r = 0.39; P < .001) but not to cardiovascular risk factor scores (r = 0.07; P = not significant). The overall correct classification rate of probable AD versus no cognitive impairment by using MTA scores was 81.8%, improving to 86.5% when combined with WMH scores. CONCLUSIONS Both MTA and WMH scores distinguished subjects with no cognitive impairment and probable AD. Combining MTA and WMH scores improved the correct classification rate, whereas WMH scores were significantly related to MTA scores, but not to cardiovascular risk factor scores. This finding suggests that among subjects with a-MCI and probable AD, WMHs on MR images are primarily associated with neurodegenerative disease.
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Abstract
BACKGROUND Despite convenience, accessibility, and strong correlation to severity of Alzheimer disease (AD) pathology, medial temporal lobe atrophy (MTA) has not been used as a criterion in the diagnosis of prodromal and probable AD. METHODS Using a newly validated visual rating system, mean MTA scores of three bilateral medial temporal lobe structures were compared for subjects with no cognitive impairment (NCI) (n = 117), nonamnestic mild cognitive impairment (MCI) (n = 46), amnestic MCI (n = 45), and probable AD (n = 53). Correlations between MTA scores and neuropsychological test scores at baseline, and predictors of change in diagnosis at 1-year follow-up were evaluated. RESULTS With NCI as the reference group, a mean MTA cut score of 1.33 yielded an optimal sensitivity/specificity of 85%/82% for probable AD subjects and 80%/82% for amnestic MCI subjects. MTA and Clinical Dementia Rating Sum of Boxes scores at baseline were independent and additive predictors of diagnosis at baseline, and of transition from NCI to MCI or from MCI to dementia at 1-year follow-up. CONCLUSION Medial temporal lobe atrophy (MTA) scores 1) distinguish probable Alzheimer disease (AD) and amnestic mild cognitive impairment (MCI) subjects from nonamnestic MCI and no cognitive impairment (NCI) subjects, 2) help predict diagnosis at baseline, and 3) predict transition from NCI to MCI and from MCI to probable AD. MTA scores should be used as a criterion in the clinical diagnosis of AD.
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Extracts prepared from primitive plant: common ladyfern (species Athyrium filix-femina) displays potent anti-cancer effects in preclinical assessments of diverse human malignant cell lines. EJC Suppl 2008. [DOI: 10.1016/s1359-6349(08)71885-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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IC‐P3‐174: Plasma Aβ level can be used as marker for AD treatment in PS1/APP Alzheimer's mouse model. Alzheimers Dement 2008. [DOI: 10.1016/j.jalz.2008.05.118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Abstract
Electroporation yields a high frequency of permanent transfectants, has a high efficiency of transient gene expression, and can be easier to carry out than alternative techniques. Electroporation makes use of the fact that the cell membrane acts as an electrical capacitor which is unable (except through ion channels) to pass current. Subjecting membranes to a high-voltage electric field results in their temporary breakdown and the formation of pores that are large enough to allow macromolecules (as well as smaller molecules such as ATP) to enter or leave the cell. The reclosing of the membrane pores is a natural decay process which is delayed at decreased temperatures. This unit presents the procedures which can be used for both transient and stable transfections.
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Abstract
Electroporation--the use of high-voltage electric shocks to introduce DNA into cells--can be used with most cell types,yields a high frequency of both stable transformation and transient gene expression,and,because it requires fewer steps,can be easier than alternate techniques. In this unit,the basic protocol describes the electroporation of mammalian cells and an alternate protocol outlines modifications for preparation and transfection of plant protoplasts.
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A diet high in omega-3 fatty acids does not improve or protect cognitive performance in Alzheimer’s transgenic mice. Neuroscience 2007; 149:286-302. [PMID: 17904756 DOI: 10.1016/j.neuroscience.2007.08.018] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2007] [Revised: 07/17/2007] [Accepted: 08/04/2007] [Indexed: 10/23/2022]
Abstract
Although a number of epidemiologic studies reported that higher intake of omega-3 fatty acids (largely associated with fish consumption) is protective against Alzheimer's disease (AD), other human studies reported no such effect. Because retrospective human studies are problematic and controlled longitudinal studies over decades are impractical, the present study utilized Alzheimer's transgenic mice (Tg) in a highly controlled study to determine whether a diet high in omega-3 fatty acid, equivalent to the 13% omega-3 fatty acid diet of Greenland Eskimos, can improve cognitive performance or protect against cognitive impairment. Amyloid precursor protein (APP)-sw+PS1 double transgenic mice, as well as nontransgenic (NT) normal littermates, were given a high omega-3 supplemented diet or a standard diet from 2 through 9 months of age, with a comprehensive behavioral test battery administered during the final 6 weeks. For both Tg and NT mice, long-term n-3 supplementation resulted in cognitive performance that was no better than that of mice fed a standard diet. In NT mice, the high omega-3 diet increased cortical levels of omega-3 fatty acids while decreasing omega-6 levels. However, the high omega-3 diet had no effect on cortical fatty acid levels in Tg mice. Irrespective of diet, no correlations existed between brain omega-3 levels and cognitive performance for individual NT or Tg mice. In contrast, brain levels of omega-6 fatty acids were strongly correlated with cognitive impairment for both genotypes. Thus, elevated brain levels of omega-3 fatty acids were not relevant to cognitive function, whereas high brain levels of omega-6 were associated with impaired cognitive function. In Tg mice, the omega-3 supplemental diet did not induce significant changes in soluble/insoluble Abeta within the hippocampus, although strong correlations were evident between hippocampal Abeta(1-40) levels and cognitive impairment. While these studies involved a genetically manipulated mouse model of AD, our results suggest that diets high in omega-3 fatty acids, or use of fish oil supplements (DHA+EPA), will not protect against AD, at least in high-risk individuals. However, normal individuals conceivably could derive cognitive benefits from high omega-3 intake if it corrects an elevation in the brain level of n-6 fatty acids as a result. Alternatively, dietary fish may contain nutrients, other than DHA and EPA, that could provide some protection against AD.
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Knowledge and usage of seat belts in an Irish pregnant population. IRISH MEDICAL JOURNAL 2006; 99:156-7. [PMID: 16892925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
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Environmental enrichment improves cognition in aged Alzheimer's transgenic mice despite stable β-amyloid deposition. Neuroreport 2004; 15:1751-4. [PMID: 15257141 DOI: 10.1097/01.wnr.0000137183.68847.4e] [Citation(s) in RCA: 170] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Environmental enrichment (EE) has been shown to improve cognitive performance and brain indices of cognition in normal mice and rats. Because the therapeutic potential of intensive, long-term EE to benefit patients with Alzheimer's disease (AD) has yet to be explored, the present study evaluated the effect of long-term EE on cognition in an animal model of AD, the APPsw transgenic mouse. Beginning at 16 months of age, APPsw mice were put into EE or standard housing for 4 months and then tested in four cognitive-based tasks (Morris maze, circular platform, platform recognition, and radial arm water maze) between 20 and 22 months of age. Our results indicate that long-term EE of aged APPsw mice results in global, overall improvement in cognitive function across these tasks without decreasing brain beta-amyloid (A beta) deposition. The results suggest that long-term EE/cognitive stimulation could provide cognitive stabilization or improvement to AD patients through mechanisms independent of A beta deposition and clearance.
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The Structure of the Metallic Derivatives Which Are Formed by Adding Grignard Reagents to Unsaturated Ketones. J Am Chem Soc 2002. [DOI: 10.1021/ja01315a058] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Effect of cytokines, dexamethasone and the A/T-signal peptide polymorphism on the expression of alpha(1)-antichymotrypsin in astrocytes: significance for Alzheimer's disease. Neurochem Int 2001; 39:361-70. [PMID: 11578771 DOI: 10.1016/s0197-0186(01)00043-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Proinflammatory cytokines and acute phase proteins, such as alpha(1)-antichymotrypsin, are over expressed in microglia and astrocytes in brain regions with abundant mature amyloid plaques, suggesting a glial cell-led brain acute phase response in the Alzheimer neuropathology. In this paper, we show that alpha(1)-antichymotrypsin gene expression in human astrocytes is elevated by interleukin-1 and interleukin-6, and further enhanced by glucocorticoid, while the homologous contrapsin gene in rat astrocytes is unaffected by these cytokines. These distinct gene regulation mechanisms might help to explain the differential susceptibility of humans and rodents to amyloid formation of the Alzheimer's type. In addition, we demonstrate that the alpha(1)-antichymotrypsin A-allele that encodes a different signal peptide and is a suggested risk factor for Alzheimer's disease gives rise to a reduced level of immature alpha(1)-antichymotrypsin in transfected cells. The physiological result would be an enhanced ability of the A-encoded alpha(1)-antichymotrypsin protein to become secreted and promote extracellular amyloid formation. We discuss our findings in terms of a model in which cytokine-induced alpha(1)-antichymotrypsin synthesis in astrocytes constitutes a specific inflammatory pathway that accelerates the development of Alzheimer's disease and could at least partly underlie the regional specificity and species restriction of the neuropathology.
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The inflammation-induced pathological chaperones ACT and apo-E are necessary catalysts of Alzheimer amyloid formation. Neurobiol Aging 2001; 22:923-30. [PMID: 11755000 DOI: 10.1016/s0197-4580(01)00308-6] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Biochemical, genetic, and epidemiological evidence indicates that inflammation is an essential part of the pathogenesis of Alzheimer's disease. Over the last decade, we and others have focused on the mechanism by which specific inflammatory molecules contribute to the Alzheimer pathogenic pathway. In particular, we have learned that several acute phase/inflammatory molecules, specifically alpha(1)-antichymotrypsin (ACT) and apolipoprotein E (apoE) that are overproduced in the AD brain can promote the formation of, and are associated with, the neurotoxic amyloid deposits that are a key pathological hallmark of the disease. Because both of these proteins bind to the Abeta peptide and catalyze its polymerization into amyloid filaments, they have been termed "pathological chaperones".ACT, and, to a lesser extent, apoE are greatly overproduced only in areas of the AD brain that are prone to amyloid formation. This restriction suggests a local inflammatory reaction may underlie the regional specificity of amyloid deposition by inducing the production of pathological chaperones. The data that will be discussed indicate that ACT over-expression is caused by the activation of ACT mRNA synthesis in astrocytes in response to increased production of the inflammatory cytokine IL-1. IL-1 is released from microglia that become activated by pre-amyloid seeds of Abeta. Recently, this inflammatory cascade has been extended to include the amyloid precursor protein (APP), for IL-1 also upregulates the production of APP in astrocytes, but at the translational rather that the transcriptional level. Thus many of the key elements of the Alzheimer's disease pathogenic pathway are products of a local inflammatory reaction in the brain. Further support for a mechanistic role of inflammation in the Alzheimer's disease pathogenic pathway has been provided by genetic studies, which have associated an increased risk of developing AD with specific polymorphisms in the apoE, ACT, and the IL-1 genes. Most recently, transgenic mouse models of AD have demonstrated that ACT and apoE are amyloid promoters/pathological chaperones in vivo whose contribution is necessary for both amyloid formation and for amyloid-associated cognitive decline and memory loss. The importance of these findings is that they help to place inflammation at the center of the pathogenic pathway to Alzheimer's disease and identify specific steps in the pathway that may be amenable to therapeutic intervention.
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Abstract
Forty-seven rotator interval regions from fetuses and 10 fresh-frozen rotator interval regions from adult cadavers were evaluated by gross dissection and light microscopy. Specimens from adults also were evaluated with ultrasound and magnetic resonance imaging. An analysis of 37 fetal specimens (> 14 weeks gestation) revealed two rotator interval types: Type I (9 of 37) was defined by a contiguous bridge of capsule consisting of poorly organized collagen fibers. A Type II rotator interval (28 of 37) had a complete defect covered by only a thin layer of synovium. Similar to the Type II rotator interval in the fetus, a rotator interval defect was present in six of eight specimens from adults. Histologically, the capsular tissue within the rotator interval consisted of poorly organized collagen fibers in specimens from the fetus and adult. Maximal opening of the rotator interval was seen by ultrasound with internal rotation and downward traction of the hyperextended arm in the coronal, oblique, and sagittal planes. Magnetic resonance imaging of the rotator interval region permitted anatomic evaluation. The complete absence of tissue in 28 of 37 fetuses suggests that the rotator interval defect is congenital. The authors recommend that surgeons carefully evaluate the integrity of the tissue within the rotator interval. When rotator interval closure is desired such as in patients with a persistent sulcus sign after arthroscopic stabilization, suturing the edges of more substantial tissue immediately adjacent to the boundaries of the rotator interval region would seem prudent.
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Magnetic resonance venography to evaluate deep venous thrombosis in patients with pelvic and acetabular trauma. THE JOURNAL OF TRAUMA 2001; 51:622. [PMID: 11535923 DOI: 10.1097/00005373-200109000-00040] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Alpha-1-antichymotrypsin promotes beta-sheet amyloid plaque deposition in a transgenic mouse model of Alzheimer's disease. J Neurosci 2001; 21:1444-51. [PMID: 11222634 PMCID: PMC6762932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2000] [Revised: 11/27/2000] [Accepted: 12/15/2000] [Indexed: 02/19/2023] Open
Abstract
Alpha(1)-antichymotrypsin (ACT), an acute-phase inflammatory protein, is an integral component of the amyloid deposits in Alzheimer's disease (AD) and has been shown to catalyze amyloid beta-peptide polymerization in vitro. We have investigated the impact of ACT on amyloid deposition in vivo by generating transgenic GFAP-ACT-expressing mice and crossing them with the PDGF-hAPP/V717F mice, which deposit amyloid in an age-dependent manner. The number of amyloid deposits measured by Congo Red birefringence was increased in the double ACT/amyloid precursor protein (APP) transgenic mice compared with transgenic mice that only expressed APP, particularly in the hippocampus where ACT expression was highest, and the increase was preceded by elevated total amyloid beta-peptide levels at an early age. Our data demonstrate that ACT promotes amyloid deposition and provide a specific mechanism by which inflammation and the subsequent upregulation of astrocytic ACT expression in AD brain contributes to AD pathogenesis.
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MESH Headings
- Alzheimer Disease/etiology
- Alzheimer Disease/metabolism
- Alzheimer Disease/pathology
- Amyloid beta-Protein Precursor/genetics
- Amyloid beta-Protein Precursor/metabolism
- Animals
- Astrocytes/metabolism
- Astrocytes/pathology
- Congo Red
- Crosses, Genetic
- Disease Models, Animal
- Glial Fibrillary Acidic Protein/genetics
- Glial Fibrillary Acidic Protein/metabolism
- Head Injuries, Penetrating/metabolism
- Head Injuries, Penetrating/pathology
- Hippocampus/metabolism
- Hippocampus/pathology
- Humans
- Mice
- Mice, Transgenic
- Organ Specificity
- Plaque, Amyloid/metabolism
- Plaque, Amyloid/pathology
- Platelet-Derived Growth Factor/genetics
- Promoter Regions, Genetic
- Protein Structure, Secondary/drug effects
- Protein Structure, Secondary/physiology
- alpha 1-Antichymotrypsin/genetics
- alpha 1-Antichymotrypsin/metabolism
- alpha 1-Antichymotrypsin/pharmacology
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Ultrastructural observations on sperm storage in the ovary of the platyfish, Xiphophorus maculatus (Teleostei: poeciliidae): the role of the duct epithelium. J Morphol 2000; 245:110-29. [PMID: 10906746 DOI: 10.1002/1097-4687(200008)245:2<110::aid-jmor3>3.0.co;2-#] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Sperm storage is an important phenomenon occurring in viviparous and oviparous teleosts and contributes to the reproductive life history of these forms. There is a paucity of morphological studies on sperm storage in fishes. The majority of these have been confined to the light level of investigation. In this report, we describe, at the ultrastructural level, sperm storage in the viviparous platyfish, Xiphophorus maculatus. Female platyfish, as is typical of the poeciliids, are capable of storing viable sperm for up to several months within the ovary and gonoduct. We observed that sperm stored within inseminated platyfish became associated with specific epithelial cells (SACs) lining the oviduct. Two forms of association were seen: 1) sperm were found within deep surface pits and pockets, and 2) the spermatozoa were taken up and incorporated within the cytoplasm of the SACs. Junctional complexes in the form of tight junctions (zona occludens) and desmosomes at the apico-lateral surfaces of the SACs were prevalent. The junctions could have contributed to allograft survival of the haploid heterogenetic sperm cells within the female's reproductive tract. Our results shed light on the mechanism of sperm storage in the platyfish and could serve as a model for other poeciliid species and teleosts that are capable of storing sperm.
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Immune response to an 18-kilodalton outer membrane antigen identifies lipoprotein 20 as a Helicobacter pylori vaccine candidate. Infect Immun 2000; 68:3337-43. [PMID: 10816482 PMCID: PMC97594 DOI: 10.1128/iai.68.6.3337-3343.2000] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Experiments were performed using the standardized murine model of Helicobacter pylori infection to determine the immunogenicity of H. pylori outer membrane vesicles in immune protection. These vesicles, which are naturally shed from the surface of the bacterium, induce a protective response when administered intragastrically to mice in the presence of cholera holotoxin, despite the absence of the urease enzyme and associated Hsp54 chaperonin. Immunoblotting identified a specific serum immunoglobulin G (IgG) response to an 18-kDa outer membrane protein in a significant number of immunized animals. This commonly expressed, immunodominant protein was subsequently identified as lipoprotein 20 (Lpp20). Hybridoma backpacks secreting an IgG1 subclass monoclonal antibody to Lpp20 were generated in H. pylori-infected mice and were found to significantly reduce bacterial numbers, providing evidence that this surface-exposed antigen is a true vaccine candidate and not merely an antigenic marker for successful, protective immunization.
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Recent advances in venous thromboembolic prophylaxis during and after total hip replacement. J Bone Joint Surg Am 2000; 82:252-70. [PMID: 10682733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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Abstract
A connection between Alzheimer's disease (AD) and Down syndrome (trisomy 21) is indicated by the fact that all Down syndrome individuals develop Alzheimer's disease neuropathology by the 4th decade of life. Previous studies have examined the frequency of aneuploidy and other chromosomal defects in cells from familial Alzheimer's disease (FAD) patients, with varying results. To investigate the possibility that a specific type of aneuploidy--trisomy 21 mosaicism--may contribute to Alzheimer's disease, we used quantitative fluorescence in situ hybridization to measure the number of trisomy 21 cells in primary fibroblast cultures from AD and unaffected subjects. The 27 AD cultures, including 15 that were derived from individuals carrying FAD mutations in presenilin 1 or 2, exhibited a significant approximately twofold increase in the number of trisomy 21 cells compared to 13 control cultures. A small double-hybridization experiment suggested that the aneuploidy in AD cells was not limited to chromosome 21 but extended at least to chromosome 18 as well. In a parallel study, the endogenous presenilin proteins in fibroblasts were localized to the centrosomes, the nuclear envelope, and its associated interphase kinetochores. Together these results indicate that the presenilin proteins may be involved in mitosis and that FAD mutations in the presenilin genes may predispose to chromosome missegregation (nondisjunction). The data reported here also suggest that trisomy 21 mosaicism may contribute to other forms of AD that are not caused by a presenilin mutation.
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Translation of the alzheimer amyloid precursor protein mRNA is up-regulated by interleukin-1 through 5'-untranslated region sequences. J Biol Chem 1999; 274:6421-31. [PMID: 10037734 DOI: 10.1074/jbc.274.10.6421] [Citation(s) in RCA: 202] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The amyloid precursor protein (APP) has been associated with Alzheimer's disease (AD) because APP is processed into the beta-peptide that accumulates in amyloid plaques, and APP gene mutations can cause early onset AD. Inflammation is also associated with AD as exemplified by increased expression of interleukin-1 (IL-1) in microglia in affected areas of the AD brain. Here we demonstrate that IL-1alpha and IL-1beta increase APP synthesis by up to 6-fold in primary human astrocytes and by 15-fold in human astrocytoma cells without changing the steady-state levels of APP mRNA. A 90-nucleotide sequence in the APP gene 5'-untranslated region (5'-UTR) conferred translational regulation by IL-1alpha and IL-1beta to a chloramphenicol acetyltransferase (CAT) reporter gene. Steady-state levels of transfected APP(5'-UTR)/CAT mRNAs were unchanged, whereas both base-line and IL-1-dependent CAT protein synthesis were increased. This APP mRNA translational enhancer maps from +55 to +144 nucleotides from the 5'-cap site and is homologous to related translational control elements in the 5'-UTR of the light and and heavy ferritin genes. Enhanced translation of APP mRNA provides a mechanism by which IL-1 influences the pathogenesis of AD.
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Abstract
Pseudoaneurysm of the dorsalis pedis artery is uncommon and is usually associated with a history of trauma to the vessel. Without such a history, the diagnosis may be challenging, because the mass may be confused with other common soft tissue masses in the foot. This case report describes a 67-year-old man with an idiopathic pseudoaneurysm of the dorsalis pedis artery that mimicked pigmented villonodular synovitis.
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A general RNA-binding protein complex that includes the cytoskeleton-associated protein MAP 1A. Mol Biol Cell 1998; 9:1695-708. [PMID: 9658165 PMCID: PMC25408 DOI: 10.1091/mbc.9.7.1695] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/1997] [Accepted: 04/17/1998] [Indexed: 11/11/2022] Open
Abstract
Association of mRNA with the cytoskeleton represents a fundamental aspect of RNA physiology likely involved in mRNA transport, anchoring, translation, and turnover. We report the initial characterization of a protein complex that binds RNA in a sequence-independent but size-dependent manner in vitro. The complex includes a approximately 160-kDa protein that is bound directly to mRNA and that appears to be either identical or highly related to a approximately 1600-kDa protein that binds directly to mRNA in vivo. In addition, the microtubule-associated protein, MAP 1A, a cytoskeletal associated protein is a component of this complex. We suggest that the general attachment of mRNA to the cytoskeleton may be mediated, in part, through the formation of this ribonucleoprotein complex.
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The essential role of inflammation and induced gene expression in the pathogenic pathway of Alzheimer's disease. FRONTIERS IN BIOSCIENCE : A JOURNAL AND VIRTUAL LIBRARY 1998; 3:d436-46. [PMID: 9545438 DOI: 10.2741/a290] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Alzheimer's disease is among the most common diseases of advanced age affecting almost one out of ten individuals who survive beyond the age of 65 years, and an another 10% for each additional decade of the life-span. The prognosis of the disease is an inexorable decline of mental functions leading to complete dependence on caretakers in the late stages of the disease. Alzheimer's disease will become a steadily increasing financial health-care problem in the industrialized world with the increasing longevity and ageing of the population. To-date there are no effective therapeutics. However, during the last years promising findings suggest that anti-inflammatory treatment strategies might be efficient. Here, we will review the experimental and epidemiological findings which support the idea that inflammatory mechanisms play an important role in Alzheimer's disease pathogenesis. The review of the experimental findings will be focussed on the amyloid-associated proteins, alpha1-antichymotrypsin and apolipoprotein E, as well as the major cytokines. In addition, the epidemiological studies on non-steroidal anti-inflammatory drugs and traumatic head injury will be summarized. We hypothesize a pathogenic model for Alzheimer's disease in which the expression of amyloid-associated proteins/pathological chaperones, induced by inflammatory cytokines, plays an essential role in accelerating the disease progress, and suggest potential targets for drug discovery based on such a model.
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Alzheimer presenilins in the nuclear membrane, interphase kinetochores, and centrosomes suggest a role in chromosome segregation. Cell 1997; 90:917-27. [PMID: 9298903 DOI: 10.1016/s0092-8674(00)80356-6] [Citation(s) in RCA: 171] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Mutations in two related genes, presenilin 1 and 2, account for most early-onset familial Alzheimer's disease. Although structural features indicate that the presenilins are membrane proteins, their function(s) is unknown. We have localized the presenilins to the nuclear membrane, its associated interphase kinetochores, and the centrosomes-all subcellular structures involved in cell cycle regulation and mitosis. The colocalization of the presenilins with kinetochores on the nucleoplasmic surface of the inner nuclear membrane, together with other results, suggests that they may play a role in chromosome organization and segregation, perhaps as kinetochore binding proteins/receptors. We discuss a pathogenic pathway for familial Alzheimer's disease in which defective presenilin function causes chromosome missegregation during mitosis, resulting in apoptosis and/or trisomy 21 mosaicism.
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Abstract
Hyperphosphorylated tau, the major component of the paired helical filaments of Alzheimer's disease, was found to accumulate in the brains of mice in which the calcineurin A alpha gene was disrupted [calcineurin A alpha knockout (CNA alpha -/-)]. The hyperphosphorylation involved several sites on tau, especially the Ser396 and/or Ser404 recognized by the PHF-1 monoclonal antibody. The increase in phosphorylated tau content occurred primarily in the mossy fibers of the CNA alpha -/- hippocampus, which contained the highest level of calcineurin in brains of wild-type mice. The CNA alpha -/- mossy fibers also contained less neurofilament protein than normal, although the overall level of neurofilament phosphorylation was unchanged. In the electron microscope, the mossy fibers of CNA alpha -/- mice exhibited abnormalities in their cytoskeleton and a lower neurofilament/microtubule ratio than those of wild-type animals. These findings indicate that hyperphosphorylated tau can accumulate in vivo as a result of reduced calcineurin activity and is accompanied by cytoskeletal changes that are likely to have functional consequences on the affected neurons. The CNA alpha -/- mice were found in a separate study to have deficits in learning and memory that may result in part from the cytoskeletal changes in the hippocampus.
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On keys and correlations in Alzheimer's disease. Neurobiol Aging 1996; 17:943-4; discussion 945-7. [PMID: 9363810 DOI: 10.1016/s0197-4580(96)00177-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Alzheimer A beta neurotoxicity: promotion by antichymotrypsin, ApoE4; inhibition by A beta-related peptides. Neurobiol Aging 1996; 17:773-80. [PMID: 8892351 DOI: 10.1016/0197-4580(96)00112-1] [Citation(s) in RCA: 82] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Two inflammation-associated proteins found in the Alzheimer amyloid deposits-alpha 1-antichymotrypsin (ACT) and apolipoprotein E4 (apoE4)-have been shown to be genetic risk factors for the development of Alzheimer's disease and to promote the polymerization of the A beta peptide into amyloid filaments in vitro. In the present study, we show that ACT and apoE4 increase the neurotoxicity of the A beta peptide in parallel with their promotion of filament formation. Preincubation of ACT or apoE4 with small A beta-related peptides, or of apoE4 with apoE2, abrogated their subsequent ability to promote both the formation and the neurotoxicity of A beta filaments. These results indicate that ACT and apoE4 may play a stimulatory role in the formation of neurotoxic amyloid in Alzheimer's disease, and that their amyloid promoting activity can be blocked by inhibitory peptides.
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Abstract
Missense mutations in the presenilin-1 (PS-1) and presenilin-2 (PS-2) genes have been shown to be causes of autosomal dominant Alzheimer's disease (the AD3 and AD4 loci, respectively). Alternative splicing has previously been reported in the PS-1 gene. In this study, elucidation of intron/exon boundary sequences revealed that PS-2 is encoded by 10 coding exons. In addition, PS-2 cDNA cloning and RT-PCR using RNA from a variety of normal tissues revealed the presence of alternatively spliced products. These products included species with in frame omissions of exon 8 and simultaneous omissions of exons 3 and 4.
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760 Involvement of ACT, apoE, AD3/PS-1, AD4/PS-2, trisomy 21, and calcineurin in the development of amyloid deposits, neurofibrillary tangles and neurodegeneration in Alzheimer's disease. Neurobiol Aging 1996. [DOI: 10.1016/s0197-4580(96)80762-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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54 Study of the AD3 and AD4 familial Alzheimer's disease genes. Neurobiol Aging 1996. [DOI: 10.1016/s0197-4580(96)80056-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Identification and expression analysis of a potential familial Alzheimer disease gene on chromosome 1 related to AD3. Proc Natl Acad Sci U S A 1995; 92:12180-4. [PMID: 8618867 PMCID: PMC40320 DOI: 10.1073/pnas.92.26.12180] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The inheritance of much early-onset Alzheimer disease (AD) has been linked to a dominant-acting locus on chromosome 14. Recently, the gene likely responsible for this genetic linkage has been identified and termed AD3. Five mutations have been found in AD3 that segregate with the disease phenotype in seven AD families and are not present in unaffected individuals. Here we report the existence of a gene encoding a seven transmembrane domain protein very similar to that encoded by AD3 in structure and sequence. This gene is located on chromosome 1, is expressed in a variety of tissues, including brain, and is predicted to harbor mutations causing nonchromosome 14 familial AD. The presence of several S/TPXX DNA binding motifs in both the AD3 protein and the AD3-like protein /AD4 protein suggests a possible role in intracellular signaling and gene expression or in linking chromatin to the nuclear membrane. Ways in which mutations in either gene could lead to AD are discussed.
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MESH Headings
- Alzheimer Disease/genetics
- Amino Acid Sequence
- Binding Sites
- Blotting, Northern
- Brain/metabolism
- Chromosome Mapping
- Chromosomes, Artificial, Yeast
- Chromosomes, Human, Pair 1
- Cloning, Molecular
- DNA, Complementary
- DNA-Binding Proteins/biosynthesis
- DNA-Binding Proteins/genetics
- Genetic Linkage
- Genetic Markers
- Humans
- Membrane Proteins/biosynthesis
- Membrane Proteins/genetics
- Models, Genetic
- Molecular Sequence Data
- Mutation
- Organ Specificity
- Presenilin-1
- Presenilin-2
- RNA, Messenger/analysis
- RNA, Messenger/biosynthesis
- Sequence Homology, Amino Acid
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Expression of the Alzheimer amyloid-promoting factor antichymotrypsin is induced in human astrocytes by IL-1. Neuron 1995; 14:447-56. [PMID: 7857652 DOI: 10.1016/0896-6273(95)90300-3] [Citation(s) in RCA: 120] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The amyloid deposits of Alzheimer's disease contain, in addition to the beta protein (A beta), lesser amounts of other proteins including the protease inhibitor alpha 1-antichymotrypsin (ACT). We have recently shown that ACT acts as a pathological chaperone, binding to the beta protein and strongly promoting its polymerization into amyloid filaments in vitro. The data of this paper show that ACT synthesis is induced in cultured human astrocytes by IL-1, a lymphokine whose expression is strongly up-regulated in microglial cells in affected areas of Alzheimer's disease brain. Furthermore, unfractionated glial cultures containing both astrocytes and microglia from human cortex (which develops amyloid in Alzheimer's disease) spontaneously express IL-1 and ACT as they reach confluence. In contrast, confluent mixed glial cultures similarly prepared from human cerebellum or brain stem, or from rat brain-tissues not prone to amyloid formation-do not express ACT unless supplemented with exogenous IL-1. The same regional difference in IL-1 expression by microglia is seen in vivo in Alzheimer's disease. These results indicate that the IL-1-induced expression of ACT may help direct the region-specific production of mature amyloid filaments in the Alzheimer brain.
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Abstract
Currently Alzheimer's disease, which affects more than 20 million people worldwide, can only be definitely diagnosed by histological examination of brain tissue obtained at autopsy or biopsy. There is a great need for an early, noninvasive, sensitive, and easily administered diagnostic test of Alzheimer's disease. Here it is reported that patients diagnosed with probable Alzheimer's disease by standard clinical criteria exhibited a marked hypersensitivity in their pupil dilation response to a cholinergic antagonist, tropicamide, placed in their eyes. It was possible to distinguish 18 of 19 individuals (95%) either clinically diagnosed with Alzheimer's disease or classified as suspect Alzheimer's individuals by neuropsychological screening from 30 of 32 normal elderly controls (94%).
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Amyloid-associated proteins alpha 1-antichymotrypsin and apolipoprotein E promote assembly of Alzheimer beta-protein into filaments. Nature 1994; 372:92-4. [PMID: 7969426 DOI: 10.1038/372092a0] [Citation(s) in RCA: 638] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The protease inhibitor alpha 1-antichymotrypsin and the lipid transport protein apolipoprotein E (apoE) are intimately associated with the 42-amino-acid beta-peptide (A beta) in the filamentous amyloid deposits of Alzheimer's disease. We report here that these two amyloid-associated proteins serve a strong stimulatory role in the polymerization of A beta into amyloid filaments. Addition of either alpha 1-anti-chymotrypsin or apoE to the A beta peptide promoted a 10- to 20-fold increase in filament formation, with apoE-4, the isoform recently linked to the development of late-onset Alzheimer's disease, showing the highest catalytic activity. These and other experiments suggest that Alzheimer amyloid deposits arise when A beta is induced to form filaments by amyloid-promoting factors (pathological chaperones) expressed in certain brain regions.
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mRNA at the synapse: analysis of a synaptosomal preparation enriched in hippocampal dendritic spines. J Neurosci 1993; 13:4054-63. [PMID: 8396172 PMCID: PMC6576444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Previous studies have demonstrated that the branched spines of the mossy fiber-CA3 hippocampal synapse contain a particularly large number of polyribosomes (Chicurel and Harris, 1989, 1992). We analyzed a preparation of synaptosomes isolated from this region and have found it to contain a restricted RNA population: certain mRNAs, presumably derived from the dendritic spines and the fine astrocytic processes surrounding the pre- and postsynaptic elements of the synapse, are enriched in the synaptosome preparation as compared to the total hippocampus; other mRNAs are less prevalent or altogether absent. In addition, neural BC1, a small noncoding RNA thought to be involved in pre- or posttranslational regulatory processes in dendrites, is a major RNA component of the dendritic spine. These results support the hypothesis that local translational regulation of gene expression may be important in establishing and modulating synaptic function.
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Identification of a chymotrypsin-like mast cell protease in rat brain capable of generating the N-terminus of the Alzheimer amyloid beta-protein. J Neurochem 1993; 61:567-77. [PMID: 8336143 DOI: 10.1111/j.1471-4159.1993.tb02160.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Cleavage after Met596 of the beta-amyloid precursor protein to generate the N-terminus of beta-protein indicates the activity of a protease having chymotrypsin-like specificity. A chymotrypsin-like protease is further implicated in Alzheimer's disease by the increased synthesis of the protease inhibitor alpha 1-antichymotrypsin in pathologically affected brain regions and by the presence in the amyloid deposits of inactivated forms of alpha 1-antichymotrypsin (indicating irreversible binding to a target chymotrypsin-like protease). In the present report, we have purified from rat brain a chymotrypsin-like protease that (a) binds with high affinity to human alpha 1-antichymotrypsin, (b) proteolytically generates a beta-protein-containing C-terminal fragment from full-length recombinant human beta-amyloid precursor protein, and (c) selectively cleaves methoxysucinyl-Glu-Val-Lys-Met- p-nitroanilide (a substrate modeling the protease recognition domain for the beta-protein N-terminal cleavage site). Amino acid sequences of tryptic fragments of the purified rat brain chymotrypsin-like protease indicate an identity with rat mast cell protease I. Moreover, the ontogeny and compartmentalization of rat brain chymotrypsin-like protease are consistent with those of connective tissue-type mast cells in the meningeal and intracortical perivasculature. Because these areas in human brain form extensive beta-amyloid deposits in Alzheimer's disease, Down's syndrome, and hereditary cerebral hemorrhage with amyloidosis of Dutch origin, the present findings suggest that a brain mast cell chymotrypsin-like protease may participate in generating perivascular beta-protein, which ultimately aggregates into beta-amyloid deposits.
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Nerve growth factor induces neuron-like differentiation of an insulin-secreting pancreatic beta cell line. Proc Natl Acad Sci U S A 1993; 90:5781-5. [PMID: 8516328 PMCID: PMC46806 DOI: 10.1073/pnas.90.12.5781] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Nerve growth factor (NGF) is the best understood of a class of trophic proteins that are important for the survival of neurons and the elaboration of their characteristic processes. Here we demonstrate that RINm5F, a rat insulinoma cell line representing an early stage in pancreatic beta cell differentiation, expresses both the Trk and p75 NGF receptors and responds to NGF by extending neurite-like (neurofilament-containing) processes. NGF treatment of RINm5F cells also induces the expression of genes normally responsive to NGF in neurons, including the NGF-1A gene. Inasmuch as pancreatic beta cells arise from the embryonic endoderm, these results suggest that NGF may play a wider role during development than previously thought-a role not restricted to cells of neuroectodermal origin--and that endocrine and neuronal cells share a developmental pathway. The specific effect of NGF on an early pancreatic beta cell line also suggests that this neurotrophic factor might form the basis of a therapeutic treatment for some types of diabetes by inducing the proliferative differentiation of islet cells.
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