Central nervous system
Brian J Pollard, Gareth Kitchen in Handbook of Clinical Anaesthesia, 2017
Although the exact detail is still poorly understood, CJD is caused by accumulation of a highly stable and resistant protein called the prion (PrP). The abnormal form has the designation PrPTSE for Transmissible Spongiform Encephalopathy. PrPTSE accumulates in the brain and initiates an inflammatory cascade which eventually results in the formation of neuronal vacuoles and neuronal cell death. Testing for PrPTSE is unreliable and the absence of the prion does not indicate absence of infectivity. PrPTSE is resistant to standard chemical and physical methods of inactivation and even autoclaving is unreliable in removing all traces of the protein. Only incineration at 850°C or higher can guarantee PrP elimination.
Caenorhabditis elegans Aging is Associated with a Decline in Proteostasis
Shamim I. Ahmad in Aging: Exploring a Complex Phenomenon, 2017
In certain rare instances, neurodegenerative disease can be caused by infectious proteins known as prion proteins (PrP). For example, Creutzfeldt–Jacob disease is a prion disorder also known as a transmissible spongiform encephalopathy (TSE). When PrP adopts an alternative, self-propagating conformation, PrPSc, disease symptoms may eventually appear [58–60]. Interestingly, like the neurodegenerative diseases described above, aging is a significant risk factor for TSEs, meaning that exposure to PrPSc may not lead to symptoms until late in life, usually after 60 years of age. Most cases of TSE are sporadic, meaning that a normal PrP-encoding gene mutates into a form that encodes the PrPSc variant during aging. Other cases are familial, such that a faulty PrPSc gene is inherited. Other cases of TSE in people occur following the ingestion of beef from cattle exposed to bovine spongiform encephalopathy, also known as mad cow disease. Once the PrPSc prion conformation forms, PrPSc itself is able to seed the misfolding of normal PrP protein into the PrPSc conformation and nucleate protein aggregation.
Micronutrients in the Management of Prion Disease
Kedar N. Prasad in Micronutrients in Health and Disease, 2019
Prion diseases are a group of rare, progressive, transmissible, incurable, and fatal neurodegenerative diseases. They are characterized by transmissible spongiform encephalopathy (TSE) and are found in mammals, including humans. In 1730’s, the symptoms of prion disease were known as scrapie in sheep and goat. In 1957, a transmissible neurological disease called Kuru, similar to Creutzfeldt-Jakob disease (CJD), was identified in the Fore tribe of Papua, New Guinea.1 Extracts from the autopsied brain samples of individuals with Kuru when administered into chimpanzees led to similar brain pathology.2 A similar cross-species infectivity was found in the United Kingdom following an outbreak of “mad cow disease.” In 1982, Dr. Stanley Prusiner of the University of California School of Medicine, San Francisco, proposed the term “prion” because pathogenic misfolded normal prion proteins caused this disease. He isolated an infective agent from the brain of sheep with scrapie and bovine spongiform encephalopathy (BSE) in cattle that causes neurodegeneration in sheep and goats.3 A similar infectious agent was isolated from brains of victims of the genetic diseases Creutzfeldt-Jakob disease (CJD) and Gerstmann-Sträussler-Scheinker syndrome (GSS). In 2012, a novel idea suggested that neurodegenerative diseases such as Alzheimer’s disease (AD) and Parkinson’s disease could be considered a prion disease.4 This view was questioned because the similarity between beta-sheet of Aβ peptides of AD and their aggregation characteristics and the characteristics of PrPsc in producing neurodegeneration is not sufficient to support this suggestion.5 Beta-sheet Aβ peptide of AD does not replicate, but PrPsc of prion disease does.
Infection Prevention: 2020 Review and Update for Neurodiagnostic Technologists
Published in The Neurodiagnostic Journal, 2020
Anna M. Bonner, Petra Davidson
One rare disorder frequently requiring successive EEG studies is Creutzfeldt-Jakob Disease. Creutzfeldt-Jakob Disease (CJD) is neither bacterial nor viral; it is a rare, but transmissible spongiform encephalopathy that is prion-based (prion: derived from “protein” and “infectious”) and known to be fatal. CJD affects approximately one person per million annually worldwide, 350 cases of which occur in the US (NIH 2019). There are three modes by which CJD is transmitted: Sporadic CJD is the most common form, accounting for more than 80% of cases, and as the name implies, this form of CJD appears without known cause or risk factors for the disease.Hereditary CJD accounts for approximately 10–15% of cases in the US and transmission is genetically based.Acquired CJD accounts for fewer than 1% of all cases (approximately 250 patients worldwide) and occurs when the disease is transmitted by exposure to the brain or nervous system tissue, such as during a medical procedure or surgery (NIH 2019; CDC 2019a).
Related Knowledge Centers
- Animal
- Cerebral Cortex
- Microscope
- Nervous System
- Prion
- Brain
- Spiroplasma
- Autopsy
- Creutzfeldt–Jakob Disease
- Gerstmann–Sträussler–Scheinker Syndrome