Alopecia areata is a systemic hair loss disorder, which affects roughly around 4.7 million people in the United States alone. [NAAF]. It is characterized as an autoimmune disease that leads to either localized or complete hair loss. The disease is independent of race, gender or age specifications, and hence affected people represent a diverse group. The effects of the disease may either be permanent or reversible depending on the nature and extent of damage to the hair follicles. It is believed that both genetic as well as environmental factors have an influence in the onset of the condition. However, the pathology of the disease is yet to be ascertained concretely. Though there is no physical distress accompanying the disease the psychological devastation suffered by the affected person is debilitating. Let us have a brief overview of the different types of alopecia before we discuss in detail the possible pathophysiology and the treatment options for the disease.
Alopecia (Different Types)
Alopecia is a disease triggered by the immune response of the body, which attacks and alters the normal development cycle of the hair follicles. Normally each hair follicle is in any one of the following three stages of life cycle namely anagen (growth phase), catagen (regression phase) and telogen (resting phase). Alopecia areata refers to the significant hair loss observed due to the immune response against the hair follicles in the anagen stage, resulting in severe reduction or complete stoppage of the hair growth phase. When the hair loss is observed throughout the body it is called as alopecia universalis. When complete hair loss is confined to the head, the condition is referred to as Alopecia totalis while hair loss that is localized and observed as patchy bald regions is known as Alopecia areata. [Ralph Paus]
Hair Follicles (Complex Morphognesis)
It is important to understand that the morphogenesis of a hair follicle is a quite complex process involving multiple genes and growth responsive factors. The complex interaction that starts with the first triggering signal from the dermis to the epithelium is followed by placode formation, which is controlled by fibroblast growth factor (FGH), ( catenin and WNT genes among other growth factors. Recent research has emphasized the important role of ( catenin in stem cell differentiation. [Huelsken, J ] The development of dermal papilla in itself is controlled by growth factors like PDGF -- A and SSH. So there are complex interactions of genes, receptors and growth factors at every level of the hair follicle formation and its life cycle. [George Cotsarelis]
Androgenic Alopecia
Androgenic alopecia is an important and most commonly observed type of the disease, which as the name suggests is triggered by the levels of the male sex hormone androgen. It is really a puzzling mystery that the very androgens, which stimulate hair growth in certain parts of the body, contribute to hair loss in some regions. This is a genetically inherited disease, which involves the miniaturization of hair follicles in certain regions of the scalp resulting in a particularly regionalized bald formation in men and women. There is a gradual shortening of the anagen phase of the hair follicles resulting in a condition called telogen effivium. (Profuse shedding of the hair shaft) Androgenic alopecia is considered as a potentially reversible condition as the hair follicles are still maintained though the growth phase is severely limited. The condition is incident in both women and men with different patterns of hair loss. While in men the hair loss is visible in the frontal regions in women it is predominant in the vertex. The androgen dihydrotestosterone (DHT) is thought to be responsible for the shrinkage of the hair follicles leading to baldy patches. It is to be noted that such structural changes in hair follicles even under normal circulation levels of androgen are manifest only in genetically predisposed individuals. [Roberts Janet] To have a better understanding of the anomaly it is essential to have a brief outlook into the changes that happen at the Molecular level.
Molecular Pathology of AGA
Research into the pathophysiology of AGA though still inconclusive, has offered enough insight and has identified the important role of androgens in the progressive miniaturization of the hair follicles leading to baldness. Testosterone and its metabolite dihydrotestosterone (DHT) in particular have been directly related as causative factors. The presence of the enzyme 5[Alpha]-reductase is essential for the catalytic reduction of testosterone into the more potent form of DHT. Chromosome 2p has the gene necessary for encoding 5[Alpha]-reductase. Extensive studies conducted on people suffering from AGA have revealed an excess of 5[Alpha]-reductase,...
RESULTS The first noticeable result was at first disappointing but turned around later in the trail. At first the rsaL mutation did not have any effect on the production of 30C12-HSL nor on lasl transcription, but it began to appear later in the logarithmic phase of propagation at which time the 30C12-HSL production along with Plasl activity reached homoeostasis in the wild strain while continuing to increase rsaL in the mutant
Molecular Basis Glanzmann Thrombasthenia An investigation of the molecular basis of Glanzmann Thrombasthenia using Polymerase Chain Reaction (PCR) The objective of this project is to investigate the molecular basis of Glanzmann Thrombasthenia (GT) using polymerase chain reaction. There have been many mutations discovered in GT patients over the years in many studies. Thus using PCR to genotype patients is one of the most effective ways of discerning the genetic basis of the
Expression Profiling of a Novel Protein A new transcription unit was discovered while working with transfected murine BAC clones, because a novel spot appeared on a 2-dimensional protein gel. Through a process of expression subcloning from the BAC clone, the transcription unit that generated the novel peptide was located. This finding was back validated by sequencing the protein contained in the 2-D gel piece using N-terminal Edman degradation and mass spectroscopy
Nanomachines The Science of molecular size machines and its engineering designs and constructions until late 1980s were not considered practicable. Nanotechnology, according to the leading exponents of that time were neither feasible nor viable, due to the fact of total structural difference of the constituent of nano-molecular device i.e. Atoms from the mechanical objects of every day life. The essential components of engineering mechanics i.e. cogwheels, gears or motors could not
laboratory-based practical work undertaken in this module was in relation to a case study of Systemic Lupus Erythematosus, SLE. SLE is a connective tissue disorder, which is autoimmune in nature. This disease affects multiple organs and its clinical manifestation is based on its severity and the organ involved. The pathogenesis of this disease is based on antigen-antibody complexes that circulate in the blood and deposit in the smaller blood
The failure of human hamster fusion in the presence of anti-human izumo antibody clearly showed that Human izumo protein is essential for fertilization. This study however has raised some new questions. The difference in fertilization capacities between wild type and Izumo +/- type was not clearly discussed. Also, the fact that ICSI of izumo -/- produces twice as many litters as did the izumo +/- type implicates the possible role
Our semester plans gives you unlimited, unrestricted access to our entire library of resources —writing tools, guides, example essays, tutorials, class notes, and more.
Get Started Now