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Kothekar H, Chaudhary K. Kuru Disease: Bridging the Gap Between Prion Biology and Human Health. Cureus 2024; 16:e51708. [PMID: 38313950 PMCID: PMC10838565 DOI: 10.7759/cureus.51708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2023] [Accepted: 01/05/2024] [Indexed: 02/06/2024] Open
Abstract
This article explores the intriguing case of Kuru disease, a rare and fatal prion disease that once afflicted the Fore people of Papua New Guinea. Scientists are still perplexed as to the origins of Kuru because efforts to discover infectious agents like viruses have been ineffective. Initial research revealed similarities between Kuru and scrapie, a neurological disorder that affects sheep, suggesting potential similarities between the two diseases. In further research, experiments in which chimpanzee brain tissue from Kuru patients was implanted led to the development of Kuru-like symptoms in the animals, suggesting a transmissible component to the condition. Furthermore, data collected from epidemiological studies highlights a drop in Kuru transmission, especially after the Fore people stopped engaging in cannibalism, and the disease showed different incubation times that affected persons within particular age groups. Neuropathological tests in the infected brain tissue have found typical intracellular vacuoles, spongiform alterations, and amyloid plaques. According to studies, Kuru susceptibility has been linked genetically to particular PRNP gene variations. Kuru and other prion disorders have few effective treatments currently, underlining the vital need for early identification. Scientists have created sensitive detection techniques to stop the spread of prion diseases and looked into possible inhibitors. Hypochlorous acid, in particular, has shown potential in cleaning processes. Besides making great progress in understanding Kuru, there are still many unresolved issues surrounding its causes, transmission, and management. The terms "kuru disease," "human prion disease," "transmissible spongiform encephalopathies," and "Creutzfeldt-Jakob syndrome" were used to search the studies; papers unrelated to the review article were removed. Eighty-four articles are included in the review text to fully understand the complexities of this puzzling disease and its consequences for prion biology and human health; additional study is essential.
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Affiliation(s)
- Himanshu Kothekar
- Anatomy, Jawaharlal Nehru Medical College, Datta Meghe Institute of Higher Education and Research, Wardha, IND
| | - Kirti Chaudhary
- Anatomy, Jawaharlal Nehru Medical College, Datta Meghe Institute of Higher Education and Research, Wardha, IND
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2
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Kuru, the First Human Prion Disease. Viruses 2019; 11:v11030232. [PMID: 30866511 PMCID: PMC6466359 DOI: 10.3390/v11030232] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 02/27/2019] [Accepted: 03/01/2019] [Indexed: 12/17/2022] Open
Abstract
Kuru, the first human prion disease was transmitted to chimpanzees by D. Carleton Gajdusek (1923–2008). In this review, we summarize the history of this seminal discovery, its anthropological background, epidemiology, clinical picture, neuropathology, and molecular genetics. We provide descriptions of electron microscopy and confocal microscopy of kuru amyloid plaques retrieved from a paraffin-embedded block of an old kuru case, named Kupenota. The discovery of kuru opened new vistas of human medicine and was pivotal in the subsequent transmission of Creutzfeldt–Jakob disease, as well as the relevance that bovine spongiform encephalopathy had for transmission to humans. The transmission of kuru was one of the greatest contributions to biomedical sciences of the 20th century.
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Milisav I, Šuput D, Ribarič S. Unfolded Protein Response and Macroautophagy in Alzheimer's, Parkinson's and Prion Diseases. Molecules 2015; 20:22718-56. [PMID: 26694349 PMCID: PMC6332363 DOI: 10.3390/molecules201219865] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 11/30/2015] [Accepted: 12/09/2015] [Indexed: 12/13/2022] Open
Abstract
Proteostasis are integrated biological pathways within cells that control synthesis, folding, trafficking and degradation of proteins. The absence of cell division makes brain proteostasis susceptible to age-related changes and neurodegeneration. Two key processes involved in sustaining normal brain proteostasis are the unfolded protein response and autophagy. Alzheimer’s disease (AD), Parkinson’s disease (PD) and prion diseases (PrDs) have different clinical manifestations of neurodegeneration, however, all share an accumulation of misfolded pathological proteins associated with perturbations in unfolded protein response and macroautophagy. While both the unfolded protein response and macroautophagy play an important role in the prevention and attenuation of AD and PD progression, only macroautophagy seems to play an important role in the development of PrDs. Macroautophagy and unfolded protein response can be modulated by pharmacological interventions. However, further research is necessary to better understand the regulatory pathways of both processes in health and neurodegeneration to be able to develop new therapeutic interventions.
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Affiliation(s)
- Irina Milisav
- Institute of Pathophysiology, Faculty of Medicine, Zaloška 4, Ljubljana SI-1000, Slovenia.
- Faculty of Health Sciences, Zdravstvena pot 5, SI-1000 Ljubljana, Slovenija.
| | - Dušan Šuput
- Institute of Pathophysiology, Faculty of Medicine, Zaloška 4, Ljubljana SI-1000, Slovenia.
| | - Samo Ribarič
- Institute of Pathophysiology, Faculty of Medicine, Zaloška 4, Ljubljana SI-1000, Slovenia.
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4
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Liberski PP. Kuru: a journey back in time from papua new Guinea to the neanderthals' extinction. Pathogens 2013; 2:472-505. [PMID: 25437203 PMCID: PMC4235695 DOI: 10.3390/pathogens2030472] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Revised: 07/04/2013] [Accepted: 07/12/2013] [Indexed: 11/30/2022] Open
Abstract
Kuru, the first human transmissible spongiform encephalopathy was transmitted to chimpanzees by D. Carleton Gajdusek (1923-2008). In this review, I briefly summarize the history of this seminal discovery along its epidemiology, clinical picture, neuropathology and molecular genetics. The discovery of kuru opened new windows into the realms of human medicine and was instrumental in the later transmission of Creutzfeldt-Jakob disease and Gerstmann-Sträussler-Scheinker disease as well as the relevance that bovine spongiform encephalopathy had for transmission to humans. The transmission of kuru was one of the greatest contributions to biomedical sciences of the 20th century.
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Affiliation(s)
- Pawel P Liberski
- Department of Molecular Pathology and Neuropathology, Medical University of Lodz, Kosciuszki st. 4, Lodz 90-419, Poland.
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5
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Yao H, Zhao D, Khan SH, Yang L. Role of autophagy in prion protein-induced neurodegenerative diseases. Acta Biochim Biophys Sin (Shanghai) 2013; 45:494-502. [PMID: 23459558 DOI: 10.1093/abbs/gmt022] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Prion diseases, characterized by spongiform degeneration and the accumulation of misfolded and aggregated PrP(Sc) in the central nervous system, are one of fatal neurodegenerative and infectious disorders of humans and animals. In earlier studies, autophagy vacuoles in neurons were frequently observed in neurodegenerative diseases such as Alzheimer's, Parkinson's, and Huntington's diseases as well as prion diseases. Autophagy is a highly conserved homeostatic process by which several cytoplasmic components (proteins or organelles) are sequestered in a double-membrane-bound vesicle termed 'autophagosome' and degraded upon their fusion with lysosome. The pathway of intercellular self-digestion at basal physiological levels is indispensable for maintaining the healthy status of tissues and organs. In case of prion infection, increasing evidence indicates that autophagy has a crucial ability of eliminating pathological PrP(Sc) accumulated within neurons. In contrast, autophagy dysfunction in affected neurons may contribute to the formation of spongiform changes. In this review, we summarized recent findings about the effect of mammalian autophagy in neurodegenerative disorders, particularly in prion diseases. We also summarized the therapeutic potential of some small molecules (such as lithium, rapamycin, Sirtuin 1 and resveratrol) targets to mitigate such diseases on brain function. Furthermore, we discussed the controversial role of autophagy, whether it mediates neuronal toxicity or serves a protective function in neurodegenerative disorders.
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Affiliation(s)
- Hao Yao
- State Key Laboratories for Agrobiotechnology, Key Lab of Animal Epidemiology and Zoonosis, Ministry of Agriculture, National Animal Transmissible Spongiform Encephalopathy Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
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6
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Abstract
Transmissible spongiform encephalopathies (TSEs) or prion diseases are the names given to the group of fatal neurodegenerative disorders that includes kuru, Creutzfeldt-Jakob disease (CJD), Gerstmann-Sträussler-Scheinker disease (GSS), fatal and sporadic familial insomnia and the novel prion disease variable protease-sensitive prionopathy (PSPr) in humans. Kuru was restricted to natives of the Foré linguistic group in Papua New Guinea and spread by ritualistic endocannibalism. CJD appears as sporadic, familial (genetic or hereditary) and infectious (iatrogenic) forms. Variant CJD is a zoonotic CJD type and of major public health importance, which resulted from transmission from bovine spongiform encephalopathy (BSE) through ingestion of contaminated meat products. GSS is a slowly progressive hereditary autosomal dominant disease and the first human TSE in which a mutation in a gene encoding for prion protein (PrP) was discovered. The rarest human prion disease is fatal insomnia, which may occur, in genetic and sporadic form. More recently a novel prion disease variable protease-sensitive prionopathy (PSPr) was described in humans.TSEs are caused by a still incompletely defined infectious agent known as a "prion" which is widely regarded to be an aggregate of a misfolded isoform (PrP(Sc)) of a normal cellular glycoprotein (PrP(c)). The conversion mechanism of PrP(c) into PrP(Sc) is still not certain.
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Affiliation(s)
- Beata Sikorska
- Department of Molecular Pathology and Neuropathology, Chair of Oncology, Medical University of Lodz, Czechoslowacka st. 8/10, 92-216, Lodz, Poland,
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Abstract
Prion diseases are a unique group of neurologic diseases caused by an abnormal protein conformation. Prion diseases encompass genetic, sporadic, iatrogenic, and acquired conditions in humans and other mammals. Although they are relatively rare, they produce a diverse array of symptoms, uniformly are fatal, and provide important information about proteins and degenerative neurobiology in addition to lessons about animal and human food chains.
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Beekes M, McBride PA. The spread of prions through the body in naturally acquired transmissible spongiform encephalopathies. FEBS J 2007; 274:588-605. [PMID: 17288548 DOI: 10.1111/j.1742-4658.2007.05631.x] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Transmissible spongiform encephalopathies are fatal neurodegenerative diseases that are caused by unconventional pathogens and affect the central nervous system of animals and humans. Several different forms of these diseases result from natural infection (i.e. exposure to transmissible spongiform encephalopathy agents or prions, present in the natural environment of the respective host). This holds true also for scrapie in sheep, bovine spongiform encephalopathy in cattle, chronic wasting disease in elk and deer, or variant Creutzfeldt-Jakob disease in humans, all of which are assumed to originate predominantly from peroral prion infection. This article intends to provide an overview of the current state of knowledge on the spread of scrapie, chronic wasting disease, bovine spongiform encephalopathy and variant Creutzfeldt-Jakob disease agents through the body in naturally affected hosts, and in model animals experimentally challenged via the alimentary tract. Special attention is given to the tissue components and spreading pathways involved in the key stages of prion routing through the body, such as intestinal uptake, neuroinvasion of nerves and the central nervous system, and centrifugal spread from the brain and spinal cord to peripheral sites (e.g. sensory ganglia or muscles). The elucidation of the pathways and mechanisms by which prions invade a host and spread through the organism can contribute to efficient infection control strategies and the improvement of transmissible spongiform encephalopathy diagnostics. It may also help to identify prophylactic or therapeutic approaches that would impede naturally acquired transmissible spongiform encephalopathy infections.
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Affiliation(s)
- Michael Beekes
- Robert Koch-Institut (P24 - Transmissible Spongiforme Enzephalopathien), Berlin, Germany.
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Affiliation(s)
- Massimo Palmarini
- Institute of Comparative Medicine, University of Glasgow Veterinary School, Glasgow, Scotland, United Kingdom.
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10
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Abstract
Prion diseases are among the most intriguing illnesses. Despite their rare incidence, they have captured enormous attention from the scientific community and general public. One of the most hotly debated issues in these diseases is the nature of the infectious material. In recent years increasing evidence has emerged supporting the protein-only hypothesis of prion transmission. In this model PrPSc (the pathological isoform of the prion protein, PrPC) represents the sole component of the infectious particle. However, uncertainties about possible additional factors involved in the conversion of PrPC into PrPSc remain despite extensive attempts to isolate and characterize these elusive components. In this article, we review recent developments concerning the protein-only hypothesis as well as the possible involvement of cellular factors in PrPC to PrPSc conformational change and their influence on the pathogenesis of prion diseases.
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Affiliation(s)
- K. Abid
- Protein Misfolding Disorders Lab, George and Cynthia Mitchell Center for Alzheimer’s Disease Research, Departments of Neurology, Neuroscience and Cell Biology and Biochemistry and Molecular Biology, University of Texas Medical Branch, 301 University Blvd, Galveston, Texas 77555 USA
| | - C. Soto
- Protein Misfolding Disorders Lab, George and Cynthia Mitchell Center for Alzheimer’s Disease Research, Departments of Neurology, Neuroscience and Cell Biology and Biochemistry and Molecular Biology, University of Texas Medical Branch, 301 University Blvd, Galveston, Texas 77555 USA
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11
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Liberski PP, Sikorska B, Bratosiewicz-Wasik J, Gajdusek DC, Brown P. Neuronal cell death in transmissible spongiform encephalopathies (prion diseases) revisited: from apoptosis to autophagy. Int J Biochem Cell Biol 2005; 36:2473-90. [PMID: 15325586 DOI: 10.1016/j.biocel.2004.04.016] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Neuronal autophagy, like apoptosis, is one of the mechanisms of the programmed cell death (PCD). In this review, we summarize the presence of autophagic vacuoles in experimentally induced scrapie, Creutzfeldt-Jakob disease and Gerstmann-Sträussler-Scheinker (GSS) syndrome. Initially, a part of the neuronal cytoplasm was sequestrated by concentric arrays of double membranes; the enclosed cytoplasm appeared relatively normal except that its density was often increased. Next, electron density of the central area dramatically increased. The membranes then proliferated within the cytoplasm in a labyrinth-like manner and the area sequestrated by these membranes enlarged into a more complex structure consisting of vacuoles, electron-dense areas and areas of normally-looking cytoplasm connected by convoluted membranes. Of note, autophagic vacuoles form not only in neuronal perikarya but also in neurites and synapses. Finally, a large area of the cytoplasm was transformed into a collection of autophagic vacuoles of different sizes. On a basis of ultrastructural studies, we suggest that autophagy plays a major role in transmissible spongiform encephalopathies (TSEs) and may even participate in a formation of spongiform change.
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Affiliation(s)
- Pawel P Liberski
- Department of Molecular Pathology and Neuropathology, Medical University Lodz, Czechoslowacka Street 8/10; pl 92-216 Lodz, Poland.
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12
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Finch CE, Stanford CB. Meat‐Adaptive Genes and the Evolution of Slower Aging in Humans. QUARTERLY REVIEW OF BIOLOGY 2004; 79:3-50. [PMID: 15101252 DOI: 10.1086/381662] [Citation(s) in RCA: 164] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The chimpanzee life span is shorter than that of humans, which is consistent with a faster schedule of aging. We consider aspects of diet that may have selected for genes that allowed the evolution of longer human life spans with slower aging. Diet has changed remarkably during human evolution. All direct human ancestors are believed to have been largely herbivorous. Chimpanzees eat more meat than other great apes, but in captivity are sensitive to hypercholesterolemia and vascular disease. We argue that this dietary shift to increased regular consumption of fatty animal tissues in the course of hominid evolution was mediated by selection for "meat-adaptive" genes. This selection conferred resistance to disease risks associated with meat eating also increased life expectancy. One candidate gene is apolipoprotein E (apoE), with the E3 allele evolved in the genus Homo that reduces the risks for Alzheimer's and vascular disease, as well as influencing inflammation, infection, and neuronal growth. Other evolved genes mediate lipid metabolism and host defense. The timing of the evolution of apoE and other candidates for meat-adaptive genes is discussed in relation to key events in human evolution.
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Affiliation(s)
- Caleb E Finch
- Andrus Gerontology Center, Department of Biological Sciences, University of Southern California, Los Angeles, California 90089, USA.
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13
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Smith PG, Cousens SN, d' Huillard Aignaux JN, Ward HJT, Will RG. The Epidemiology of Variant Creutzfeldt-Jakob Disease. Curr Top Microbiol Immunol 2004; 284:161-91. [PMID: 15148992 DOI: 10.1007/978-3-662-08441-0_7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
Variant Creutzfeldt-Jakob disease (vCJD) was identified as a new disease in 1996. It was linked to infection with the bovine spongiform encephalopathy (BSE) agent although the epidemiological evidence for this was not strong, but later strain typing studies confirmed the association. The disease has affected predominantly young adults whose dietary and other characteristics are unexceptional compared to control groups, other than that all patients to date have been methoinine homozygous at codon 129 of the prion protein gene and the incidence has been about two times higher in the North of the UK. The number of cases in the 7 years after first identification of the disease has been considerably lower than initially feared, given the likely widespread exposure of the UK population to the BSE agent through contaminated beef products. Predictions of the possible future course of the epidemic have many associated uncertainties, but current mathematical models suggest that more than a few thousand cases is unlikely. Such modelling is limited by the absence of a test for infection with the vCJD agent. The development of a test that could be used on easily accessible tissue to detect infection early in the incubation period would not only advance understanding of the epidemiology of infection with the agent but would also aid the implementation of control measures to prevent potential iatrogenic spread.
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Affiliation(s)
- P G Smith
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK.
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Macalister GO, Buckley RJ. The risk of transmission of variant Creutzfeldt–Jakob disease via contact lenses and ophthalmic devices. Cont Lens Anterior Eye 2002; 25:104-36. [PMID: 16303485 DOI: 10.1016/s1367-0484(02)00008-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
This review collated the available information regarding the risk of transmission of variant Creutzfeldt-Jakob disease (vCJD) via contact lenses and other ophthalmic devices. The topics examined include: the emerging background science of the unconventional infective agent, the prion, particularly those factors affecting transmission; the estimates of the number of undiagnosed infective individuals; and evidence of infectivity in the external eye. Despite many uncertainties in the literature, we conclude that cross-infection is theoretically possible. An assessment of the extensive search for a complete inactivation procedure resulted in the recommendation of the use of sodium hypochlorite (NaOCl), which does not appear to distort rigid lenses. Further tests are required for other devices.
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Affiliation(s)
- Graham O Macalister
- Department of Optometry and Visual Science, City University, Northampton Square, London EC1V OHB, UK
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15
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Abstract
The kuru epidemic lasted almost a century; it started in 1901-1902, reached epidemic proportions in the mid-1950s, and disappeared in the 1990s. Kuru is the prototype member of a group of disorders known as transmissible spongiform encephalopathies (TSEs) or prion diseases. Recent data on the genetics and pathogenesis of TSEs contribute to a better understanding of the documented kuru phenomena, and vice versa, observations made during the kuru epidemic are immensely helpful in understanding the epidemic of variant Creutzfeldt-Jakob disease that is currently developing in Europe. The major goal of this review is to identify and illustrate these points.
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Affiliation(s)
- Lev G Goldfarb
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Room 4B37, Bldg 10, 10 Center Drive, Bethesda, MD 20892-1361, USA.
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16
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Abstract
A change in handedness (chirality) in some amino acids appears to be the basic physical change in degradation-resistant proteins (prions) found in conditions such as Creutzfeldt-Jacob disease (CJD), Alzheimer's disease (AD), bovine spongiform encephalopathy (BSE) and ovine scrapie. The affected structures are primarily innervated by cholinergic nerves. Much evidence suggests that these so-called prions (here named chirons) are harmless, non-infectious products. The importance of the cholinergic system allows a new simplified interpretation of these conditions. The main steps are the acetylcholine-cholinesterase splitting of body water with release of free protons in solution, followed by electron dissipation, dioxygen activation and Ca-fluxes. Abiotic physics conserves parity and symmetry by equal amounts of L- and D-forms of molecules. In contrast, the asymmetric pattern of life must be homochiral. Such biomolecules dissolve in water and are thus able to interact in cholinergic hydrodynamics. It is supposed that the instability of the composite weak force by beta-decay causes changes in chirality. These extremely rare events are not frequent enough to explain disease pathology. Experimental, accidental, surgical and abusive inoculations will propagate chirons according to the physical law of self-replication, which also occurs in test tubes without added biological products. Chirons will not be degraded into amino acids in the alimentary canal and will, because they are indigestible, leave the body with the faeces. Chirons are inert also to the immune system and will be engulfed without reaction by phagocytosing cells. They are then stored away in tissues, where they do no harm (if not detected and suspected to be deleterious, thereby causing pathogenic anxiety). The cholinergic system reacts to all kinds of integrity threats and it is this reaction which I propose causes the so-called prion diseases. This pathology seems generally valid, and is here exemplified in AD, CJD, and Kuru disease. It is the cholinergic reaction and not the agent per se that is pathogenic. This is also true of viral infections where the interaction between viral infection and response may explain the enigmatic epidemiology of many neurodegenerative diseases. Intensity and duration of challenges will determine pathophysiology. The new variant of CJD, vCJD, is assumed to result from mutation of a slow virus agent into a more intense variant, which will give disease in younger patients. The pathology is primary protonic, with overactivity in most sub-systems of either enhancing or inhibiting character, but also functional failure or cell death by membrane damage and acidification, for instance in the CNS. The practical results of this proposal will be alleviation of the current BSE crisis. The important main aspects are: chirons are not infectious proteins but inert physical by-products; they are indigestible and not immunogenic, so beef is safe; properly processed and handled meat and bone-meal are not likely to transmit neurodegenerative diseases; chirons cannot even serve as markers in neurologic diseases.
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Affiliation(s)
- S Axelsson
- Department of Obstetrics and Gynaecology, Swedish University of Agricultural Sciences, Uppsala, Sweden.
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17
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Collins S, McLean CA, Masters CL. Gerstmann-Sträussler-Scheinker syndrome,fatal familial insomnia, and kuru: a review of these less common human transmissible spongiform encephalopathies. J Clin Neurosci 2001; 8:387-97. [PMID: 11535002 DOI: 10.1054/jocn.2001.0919] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Creutzfeldt-Jakob disease (CJD), Gerstmann-Sträussler-Scheinker syndrome (GSS), fatal familial insomnia (FFI) and kuru constitute major human prion disease phenotypes. Each has been successfully transmitted in animal models and all are invariably fatal neurodegenerative disorders, with the brains of affected individuals harbouring variable amounts of an abnormal, protease-resistant form of the prion protein (PrPres), which is inextricably linked to pathogenesis and transmissibility. Classical sporadic CJD is the most common human transmissible spongiform encephalopathy (TSE), but recently the variant form (vCJD), first described in the UK in 1996, has drawn considerable attention. In contrast to sporadic CJD, FFI and GSS are almost invariably genetically determined TSEs, caused by a range of mutations within the open reading frame of the prion protein gene (PRNP) on chromosome 20. By definition, the nosologic term FFI is reserved for patients manifesting prominent insomnia, generally in combination with dysautonomia, myoclonus, and eventual dementia, with the predominant pathologic changes lying within the thalami and a specific underlying mutation in PRNP. GSS, however, encompasses a more diverse clinical spectrum ranging from progressive cerebellar ataxia or spastic paraparesis (both usually in combination with dementia), to isolated cognitive impairment resembling Alzheimer's disease. Additional extra-pyramidal features, which may respond to dopaminergic therapy can also be seen. Neuropathological findings are also relatively diverse, partly overlapping with those found in Alzheimer's disease, especially the presence of neurofibrillary tangles (NFTs). Although GSS and FFI in their classical forms are differentiable clinical profiles, such divisions may have no intrinsic biological validity given the considerable intra-familial clinico-pathological diversity so commonly seen. Kuru constitutes a horizontally transmitted prion disease, which after a lengthy incubation period, presents clinically as a progressive cerebellar ataxia associated with tremors. It has now almost disappeared since the cessation of ritualistic endocannibalism in the late 1950s but was previously exclusively endemic amongst the Fore linguistic group and neighbouring tribes in the Eastern Highlands of New Guinea. Uniform topographical central nervous system histopathology includes spongiform change and neuronal loss, with amyloid (kuru) plaques in approximately 75% of cases.
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Affiliation(s)
- S Collins
- Australian Creutzfeldt-Jakob Disease Registry, The University of Melbourne, Parkville, Victoria, Australia.
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18
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Abstract
The tubulovesicular structures (TVS) are the only structures unique at the level of thin-section electron microscopy for all TSEs so far examined. They were first described in NIH Swiss mice infected intracerebrally with the "Chandler" strain of scrapie by David-Ferreira et al. in 1968 [Proc. Soc. Exp. Biol. Med. 127:313-320]. TVS were described as "particles and rods ranging in diameter from 320 to 360 A(o)." The exact topology of TVS is not entirely clear. In most published electron micrographs, TVS appeared as spheres measuring between 20 and 40 nm in diameter. The number of neuritic processes containing TVS increases through the incubation period and has been shown to correlate with the incubation period and titre of infectivity in three longitudinal disease studies of scrapie and CJD. These studies, therefore, suggest that TVS may represent a primary pathogenetic event rather than a pathological product of disease. The predominant theory of the scrapie agent is now the "prion hypothesis" and its derivatives, which implies that a conformationally altered abnormal isoform (PrP(Sc) or PrP*) of a normal cellular membrane glycoprotein (PrP(c)) is the agent and its accumulation merely mimicks replication. If an abnormal fraction of PrP is indeed the infectious agent, (although it is no longer suggested in some quarters that protease resistant fraction of PrP(Sc) is the agent). The absence of stainable PrP in TVS, however, would indicate that they are not the ultrastructural correlate of the agent. However, TVS appear to be specific and unique to the TSEs, appearing before the earliest pathological changes and increasing in line with incubation period or titre. The very existence of TVS and their correlation with infectivity, therefore, urgently needs an explanation.
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Affiliation(s)
- P P Liberski
- Laboratory of Electron Microscopy and Neuropathology, Department of Molecular Biology, Chair of Oncology, Medical Academy Lódz, Lódz, Poland.
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19
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Lueck CJ, McIlwaine GG, Zeidler M. Creutzfeldt-Jakob disease and the eye. I. Background and patient management. Eye (Lond) 2000; 14 ( Pt 3A):263-90. [PMID: 11026987 DOI: 10.1038/eye.2000.75] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
This article attempts to summarise our current understanding of TSEs as they affect man. Specific aspects relevant to ophthalmological practice, in particular the management of patients in day-to-day clinical practice and with respect to corneal transplantation, have been discussed. In the companion article we discuss the specific ophthalmic and neuro-ophthalmic features of these diseases.
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Affiliation(s)
- C J Lueck
- Department of Clinical Neuroscience, Western General Hospital, Edinburgh, UK.
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20
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Abstract
Creutzfeldt-Jakob disease (CJD), the first transmissible spongiform encephalopathy (TSE) to be described in humans, occurs in a sporadic, familial, or iatrogenic form. Other TSEs in humans, shown to be associated with specific prion protein gene mutations, have been reported in different parts of the world. These TSEs compose a heterogeneous group of familial diseases that traditionally have been classified as familial CJD, Gerstmann-Sträussler-Scheinker syndrome, or fatal familial insomnia. In 1996, a newly recognized variant form of CJD among young patients (median age, 28 years) with unusual clinical features and a unique neuropathologic profile was reported in the United Kingdom. In the absence of known CJD risk factors or prion protein gene abnormalities, the UK government concluded that the clustering of these cases may represent transmission to humans of the agent causing bovine spongiform encephalopathy. Additional epidemiologic and recent laboratory data strongly support the UK government's conclusion.
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Affiliation(s)
- E D Belay
- Division of Viral and Rickettsial Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA.
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