CJD: A Prion Disease With Abnormal Isoform Proteins - Essay Sample

Introduction

Creutzfeldt-Jakob disease (CJD) is a human prion disease. It is a condition of the neurodegenerative disorder with the standard features of the clinical and the diagnostic characteristics (Brown, 2008). The disease is primarily believed to be caused by a case of an abnormal isoform of the cellular glycoprotein referred to as the prion protein.

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CJD Pathophysiology (Mechanism)

Concerning the CJD Pathophysiology, the defective proteins can be transmitted through some of the defective proteins and corneal graft, electrode implants as well as human hormone (Lasmezas, 2016). The disease affects some of the parts of the human brain. In the form of familial CJDs, a mutation has occurred in the gene for PrP in that family. The normal protein PrPc is 35 KD membrane glycoprotein, and is normally sensitive to proteinase and also water-soluble (Collinge, 2009). PrPSc or PrPTSE, which is the abnormal protein, arises from folding pattern change of PrPc, making it more resistant to the proteases actions and causes it to come out as the insoluble amyloid precipitate. The conversion leads to neuronal degenerating, as well as the loss by the mechanism, which is unknown (Palmer, 2015). PrPc undergoes encoding by the gene PRNP on chromosome 20 and hence plays a critical role in the cellular functions.

CJD Molecular Anatomy

Self-propagation is the main feature of prion disease. Once the PrPSc is introduced into the body from the environment or generated endogenously, then it converts the normal prions into the abnormal ones. Such conversion starts with the initial production of the small misfolded polymer prions, i.e., less than 28 molecules (Johnson, 2008). This converts the adjacent prions through unknown mechanisms into abnormal ones. With the production of more PrPSc polymers, then there is a continued propagation of the normal to abnormal prion conversion. Therefore, nothing or little is known concerning the molecular state of the proteins causing self-replicating disease material.

CJD Diagnosis

The doctors normally suspect the disease's diagnosis in relation to the typical signs and symptoms as well as the disease's progression. In most of the patients suffering from the condition, the cerebrospinal fluid's protein or even a typical electroencephalogram pattern are both seen as the ways of diagnosing the CJD (Ironside, 2012). However, CJD's confirmatory diagnosis demands immunodiagnostic and neuropathology testing of the tissues of the brain obtained at either autopsy or biopsy. In the iatrogenic cases, person to person transmission of the disease has been associated with the corneal transplant during mater grafts, the peripheral injections of the pooled pituitary gland extracts and the use of the contaminated neurosurgical instruments (Lasmezas, 2016).

How Prions Can Cause CJD

CJDs are mainly caused by prions. The prions are special kinds of proteins occurring within the neurons of the central nervous system. The protein can affect the signaling processes once misfolded, leading to the neuron damages and causing degeneration, which can result in spongiform appearance in the brain parts which are affected (Masters, 2013). For the condition's diagnosis and treatment, there has been no certain cure for the CJD, but some of the symptoms, for instance, twitching, can be managed (Johnson, 2008). The main treatment that can be used is through palliative care. Cases like depression and anxiety can be treated using the antidepressants or the sedatives.

What Exactly Happens To the Brain?

The disease can have an impact to the human brain whereby the condition's symptoms are caused by the progressive failure of the nerve cells in the brain, which are commonly associated with the abnormal prion protein's build-up forming within the brain (Collinge, 2010). In the case of the examination of the brain tissues of the person infected with the CJD using the microscope, some of the tiny holes can be seen where the nerve cells have failed. Some of the brain's parts may resemble a sponge where the prion was infecting the brain's areas (Nitrini, 2013).

In The Familial CJD What Genes Are Involved?

For the familial CJD, it is usually an inherited condition, and some of the common forms of this category are Gerstmann-Straussler-Scheinker disease (GSS) and fatal familial insomnia (FFI) (Mok, 2017). The familial autosomic by a range of the mutations within the open reading frame prion protein gene (PRNP) on chromosome 20. The copies of the PrP-gene are inherited from the mother and the other from the father. The familial forms of the prion disease are inherited through a dominant, autosomal pattern meaning that a copy of the altered PRNP gene in every cell is enough to cause the disorder.

How People Get The Disease And What Gets Affected In The Body

During the period of the incubation as well as the active prion disease clinical phase, PrPTSE might be present (i.e., can result in the transmission of the disease) in all the tissues as well as the body fluids, particularly the brains, skeletal muscles, and nerves. The intracytoplasmic vacuoles appear initially in the neurons. With the progress of the disease, vacuolization will be more prominent, and hence the cortical neutrophil leads to the appearance of the spongiform hence the term spongiform encephalopathy.

References

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