Essay on Prion Diseases

In bovine spongiform encephalopathy (BSE), the disease is caused by the misfolding of proteins that cause proteins and peptides to develop a fibrillary structure. The PrPc is a correctly folded prion and the misfolded form is called PrPSc. BSE occurs when the normal PrPc come into contact with the toxic PrPSc and the normal prion takes on the shape of the PrPSc. The normal chaperones are unable to convert the PrPSc back to the normal form. The PrPSc now takes on the role of chaperone and the conversion of PrPc prions continue over and over. PrPSc, now being hydrophobic avoids the water of the inner cell and begin to accumulate and form plaques along the neuronal cell membranes. The aggregation of the prions on the cell membrane eventually lead to cell death which produces the sponge-like appearance in the brain of cattle infected with BSE (Thompson, 2014).

Classic CJD Creutzfeldt-Jakob disease is a human prion disease. This disease is very progressive and always fatal. Infection with this disease leads to death usually within 1 year of illness. This fatal disorder is believed to be caused by an abnormal isoform of a cellular glycoprotein known as the prion protein. CJD occurs worldwide and the estimated incidence in many countries, including the United States,.CJD is classified as a transmissible spongiform encephalopathy (TSE) along with other Prion diseases that occur in humans and animals. In about 85% of patients, CJD occurs as a Irregular disease with no recognizable pattern of transmission. A smaller part of patients (5 to 15%) develop CJD because of inherited mutations of the prion protein gene. These inherited forms include Gerstmann-Straussler-Scheinker syndrome and fatal insomnia. In most CJD patients, the presence of 14-3-3 protein in the cerebrospinal fluid and/or a typical (EEG) pattern, both of which are believed to be diagnostic for CJD .A conformed diagnosis of CJD requires neuropathology or immunodiagnostic testing of brain tissue obtained either at biopsy or autopsy.

Variant Creutzfeldt-Jakob disease (vCJD) is a rare and fatal human neurodegenerative condition falling under the category of Transmissible Spongiform Encephalopathy (TSE) because of having characteristic of spongy degeneration of the brain that it causes and its ability to be transmitted. First it was described in the United Kingdom in March 1996 and it has been connected with exposure to a TSE of cattle known as Bovine Spongiform Encephalopathy (BSE) sometimes called Classical BSE, having been reported first in 1986 in the United Kingdom.

     Mad Cow Disease, scientifically referred to as (BSE) Bovine Spongiform Encephalopathy, is a disease that affects those humans who eat the meat from infected cows. Mad Cow Disease is one of several fatal brain diseases called (TSE) Transmissible Spongiform Encephalopathy. (USDA) There was evidence of a new illness resembling the sheep disease scrapie. It was technically named BSE but quickly acquired the mad cow tag because of the way infected cattle behave. (CNN) In 1997, there was an award given to Stanley Prusiner, for concluding that a distorted protein called a prion was responsible for Mad Cow Disease, noted the long incubation period made it difficult to distinguish (Bryant).

Humans have to deal with many different diseases and the ones most disliked are the ones with no cures. Like cancer, transmissible spongiform encephalopathies have no cure, but they are more rare. These diseases are prion diseases which cause the brain to deteriorate. Prions are proteins that sometimes behave like viruses, which mean that they should have some form of nucleic acid, but since they don’t, they cause abnormalities. The nervous system contains many normal prions, but when an abnormal prion comes along, it transforms all the normal prions into abnormal ones. Bovine spongiform encephalopathy is found in cattle, but it can be transmitted to humans.

Read the scenario and answer the questions in no less than 200 words each. Support your responses with detail from this week’s assigned video and reading. Include APA-formatted citations and references.

BSE is caused by the misfolded prion protein known as PrPsc which originated from PrPc protein. Prion proteins are formed when PrPc becomes a misfolded polypeptide chain – a change in the shape of the protein. PrPsc influences the folding of PrPc multiple times leading to aggregates to form fibers that

This disease gets its name from the German neurologist Hans Gerhard Creutzfeldt and Alfons Maria Jakob that first identified this disease. (Victor, 2015) VCJD is primarily found in the brain of the cattle. Abnormal proteins called prions have thought to be the cause of this disease in both cattle and in humans. These prions cause tiny holes that look like a sponge under a microscope. (Melissa Conrad Stöppler, 2015) Unlike most viruses and bacteria these prions unfortunately do not die when exposed to heat, ultraviolet light, and radiation. Disinfectants that are usually used to kill viruses and bacteria also do not work to kill prions. Even cooking the meat very well will not lower the risk of prions in the

Proteinaceous Infectious Particles, commonly known as Prions, are extremely rare misfolds of the protein PrPc, which cause fatally neurodegenerative diseases, and are theorized to be infectious only by the protein itself (U.S National Library of Medicine, 1998). This “protein-only theory” is still heavily debated today, as some scientists deny the theory, and there isn’t a significant amount of evidence on each side to qualify the theory or disprove it (Soto, C. 2011). The base “Prion” protein is encoded in the gene PRNP, while being non-infectious. Prions are most commonly found in human prion diseases, but they can also be in other animals in the form of Mad Cow Disease and Chronic Wasting Disease, classified as Bovine Spongiform Encephalopathies

While dysfunction of prion proteins remains the most widely accepted etiology of BSE, the USDA suggests there may be two other possible theories that could better explain the manifestation of BSE: the virino theory and the virus theory. However, both theories pale in comparison to the robust evidence in support of the prions theory. A major argument that works against both the virino theory and virus theory is that throughout several studies, the use of various treatments known to damage or inhibit nucleic acids have had no effect on the transmissibility of BSE. Interestingly, prion proteins lack nucleic acids – making them an excellent candidate as the infectious agent responsible for the development of bovine spongiform encephalopathy.

Creutzfeldt - Jakob disease is a prion disease characterized by the degeneration of the cerebral cortex, basal ganglia, cerebellum, brainstem and spinal cord. CJD is classified into 4 types: sporadic, familial, iatrogenic, and contaminated meat. CJD represents approximately 85% of all human prion diseases . Although it is common in older ages (50-70), both men and women have an equal chance of acquiring the disease. Recently, there has been a new variant CJD that is thought to be from the ingestion of cattle products in Great Britain. The central characteristic that differentiates vCJD and CJD is that it occurs more commonly in younger people and also has different pathogenic findings. The second variant form is the panencephalopathic form, which is found in Japan.

Prions are an incongruous pathogen that is causative of transmissible spongiform encephalopathies (TSE); a group of fatal neurodegenerative diseases found in mammals. This abnormal proteinaceous particle is believed to be a post-translational mutation of a normal cellular protein found in the brain (Emmanuel, 2002). This naturally occurring pathogen acts similarly to a viral infection, however as it lacks nucleic acid it is invulnerable to death via means of antibiotics or sterilisation. PrPc and PrPsc, the known prion proteins indicative of TSE’s, are known to bind to the surface of neurons and fold these proteins into an abstract spongiform structure. Although the process inducing this folding mechanism is unknown, it is

Many scientists hypothesize that protein dysfunction plays a role in the progressive damage and death of nerve cells. The nerve cells may be blocked from communication

PD is increasingly recognized as an extensive multi-system disease with widespread neurological impairment, affecting a variety of brain regions not directly involved in motor control. The extranigral pathology includes the olfactory bulb, the dorsal motor nucleus of the glossopharyngeal and vagal nerves, the intermediate reticular zone, subnuclei of the reticular formation and the raphe system, the locus coeruleus (LC), regions of the basal forebrain, many subnuclei of the thalamus and amygdala, and, in severe cases, the neocortex [64-67]. In 2003, Heiko Braak and colleagues [68] traced the course of the pathology in incidental PD cases and developed a staging procedure based on the location of α-synuclein-containing inclusion bodies, also

A common observation in the brain of people who have died from Alzheimer’s is that plaques and tangles make from protein fragments are present. (A Century of Alzheimer’s Disease)