Alzheimer's Disease

by:

Michael

Sang

Alzheimer's Disease

Introduction to Alzheimer's

       Alzheimer's disease is a progressive degenerative disease of

the brain. It is first described by the German neuropathologist Alois

Alzheimer (1864-1915) in 1905.  This disease worsens with advancing age,

although there is no evidence that it is cause by the aging process.

The average life expectancy of a person with the disease is between

five and ten years, but some patients today can live up to 15 years due to

improvements in care and medical treatments. The cause of Alzheimer's

has not been discovered yet and it cannot be possible to confirm a person

has Alzheimer's until their autopsy following death.

How does Alzheimer's develop

What causes Alzheimer's? Well no one know exactly the

development

of this debilitating disease. But recent advances has produced several clues

as to how it is born. Initially when we study the brain of a Alzheimer's

victim, we focus on two specific areas. One is the cortex of the frontal and

cerebral lobes1. The second is the hippocampus (meaning seahorses in

Greek which it resembles2) which is located below the cerebral cortex and

responsible for short-term memory. If we study samples of these two

section, we would find three irregularities which are not found in normal

brain matter. These three are called neurofibrillary tangles, neuritic plagues

and granulovacuolar degeneration3.

A nerve cell has numerous axons and dendrites coming out of it. A

neurofibrillary tangle is when the neuron changes. A number of dendrites

are missing and the nucleus is filled with protein filaments resembling steel

wool4.

Although all elderly people has a few of these helix shaped bundles in their

brain for they are normal indicators of aging, Alzheimer's patients has more

than usual. Their presence usually in the frontal and temporal lobes is a

indication of AD.

Senile neuritic plagues are small round objects. They are masses of

amyloid protein material composed of residue left over from healthy nerve

endings that were broken off and decayed. Their presence near the cell

further indicates something gone wrong. Neuritic plaques is the best

evidence for diagnostics to make the determination of AD.

A third sign of neuron deterioration is granulovacuolar degeneration.

This is when fluid-filled vacuoles are seen crowding inside the nerve cell,

specifically in the triangular shaped cells of the hippocampus. This

condition can only be observed in carefully sliced, stain and analyzed brain

tissue.

The cell having lost all it's dendrites and nucleus soon disintegrates

entirely, vanishing into the body's waste disposal system. With the

depletion of enough nerve material the brain actually shrinks, sometimes by

as much as ten percent5. The more cells the AD sufferer loses, the more

mental functions he loses. Soon the person will have limited motor skills.

People who were once witty and quick on their feet were reduced to the

mental status of small children.

Diagnosis of Alzheimer's

How would you now if a person you knew has Alzheimer's? There

are certain telltale signs that point to it. There was one patient6 that was

convinced she was suffering from AD. As proof of her condition, she

bought the a meeting several recent newspaper clippings, which she began

to quote from memory. Obviously this person did not have the disease,

she wouldn't have memorized complex and lengthy information. But

forgetting on a regular basis doesn't indicate Alzheimer's either.

Stages of AD

In the initial stage, there is no clear evidence of memory trouble and

deterioration in brain functions. The individual performs well on exams that

test mental abilities (psychometric tests7) similar to those given to measure

IQ.

In the second stage, the patient shows very mild memory problems

with difficulty in remembering names of friends. The changes at this point

is still very small. Occasionally, the patient might make a surprising

statement such as inquiring about the health of a friend who everyone

knows, died years ago. Only extensive psychometric testing can determine

if the person's mental ability changed. A close family member like a

husband or wife might suspect something is wrong.

By the third stage, there is definite evidence of memory loss, which

might interfere with job performance, The person might have difficulty

competing a job that use to be routine. The person may avoid social

situations because he or she realizes there's a problem

In stage four there is clinical evidence of memory impairment when

the mental status is tested by doctors. The disease has now become

obvious to the family. A sign of this stage is when the patient keeps asking

the same question which has already been answered, this make daily

companionship difficult because his friends and family are frustrated.

By stage 5, the patient show problems with both recent and past

memories, they even forget events that are important like Christmas,

birthdays, friendships and interests. Judgment is failing, the individual is no

longer able to select clothes for a particular weather of season and cannot

match items by color. Eventually, the victim of AD may leave the water

running, the stove on, or the front door open. At this point wandering

becomes a major problem.

In stage six, understanding of languages diminishes and simple

commands aren't understood. Victims may go back to their first language

if they have one. Eventually languages disappear entirely.

In stage seven or the terminal stage, the victim becomes bedridden

and totally dependent for all functions. He cannot speak coherently and

can't eat unassisted. Death usually occurs at this stage form aspiration

pneumonia8,  pneumonia caused by breathing in food or other objects

because the victim doesn't remember how to swallow food safely, or from

urinary infections.

                                                                                                               

Recent Research on Alzheimer's

Some progress has been made in understanding the nature of the

Alzheimer's disease. Scientists has recently found medicine that can slow

down the progress of AD. The average survival period from the time of

diagnosis to death in 1985 is 10 years. Today the rate has increase a third

to 15 years9.

A recent media release stated the discovery of a mutant gene called

"triplet repeat" disease genes10. These genes produce proteins that may

block from properly functioning key enzymes that are important to the

production of energy in the brain. This gene was found in several diseases

like AD, Huntingtons, and Haw River Syndrome as well as three other  rare

neurological disorders.

Another press release from the Alzheimer's Association is one

concerning the new study of an important advance toward early detection

of AD11. "Through investigations such as these, in addition to those

involving apolipoprotien E (APOE), positron emission tomography (PET),

and other approaches, we will improve our ability for accurate detection of

individual at risks for the disease"12 said Zaven Khachaturian Ph.D.,

director of the Alzheimer's Association's Ronald and Nancy Reagan

Research Institute.

Among the drugs being tested to treat AD are

-Cholinergic agents: choline, lecithin, and the agonist (RS 86, arecholine,

and bethanechol)

-Peptides: vasopressin, ACTH 4-10, naloxone

-Nootropic agents: pramiracetem, CI 911, Praxilene, Oxiratem

-other general drugs: chelating agents, Nimodipine, Vinpocetine13

most of these are still in experimental stages. Some has proved to work

slightly but is generally unsafe, others has tested safe but not beneficial, but

none has been both. People who offer "cures" to Alzheimer's are either

frauds or ignorant14.

When people realizes that AD is a serious disease, perhaps as much

as HIV, then maybe they will pay attention. The reason why there hasn't

been a cure is because scientists tries to attract grants by working on a

problem that people think is serious and controversial. If there was as

much attention that was paid to AIDS as there was in AD, then maybe

there will be an answer.