New Study Discusses the Origin of Amyotrophic Lateral Sclerosis (ALS)

Amyotrophic Lateral Sclerosis (ALS) is a condition wherein there is attack on the nerve cells causing nerve damage.  The exact etiology is unknown, however a recent study shows that this could be due to an error in protein formation.

Amyotrophic Lateral Sclerosis (ALS)

Amyotropic lateral sclerosis, otherwise known as Lou Gehrig’s disease is a progressive neurological disorder in which there is damage to nerve cells or neurons that control voluntary muscles of the body. This medical condition belongs to a group of disorders known as motor neuron disorders which are characterized by the damage and death of neurons.

For us to understand what happens in ALS, let us first recall what motor neuron cells are. Motor neurons are nerve cells that are located in the central nervous system such as the brain, the spinal cord and the brainstem. These cells function as control units which branch out to other parts of the nervous system and the voluntary muscles of the body. What happens in ALS is that the upper motor neurons, that is the motor neurons in the brain, and the lower motor neurons or the neurons found in the spinal cord degenerate or even die, thus failing to send signals to the muscles. What happens is that these muscles weaken and waste away. These muscles may eve twitch or have fasciculations. The brain loses control over voluntary movement as a result.

This further causes weakness and disabilities found in ALS. The voluntary muscles are affected and the body is unable to move arms, legs and other parts of the body. ALS can also affect the muscles of the diaphragm and the chest wall, causing limitation in breathing without ventilator support. Eventually, this can cause deaths due to respiratory failure which may occur within 3 to 5 years from the onset of symptoms. A few patients afflicted with this disorder survive and live for another 10 or more years. Aside from physical disorders, the disease may also affect cognitive function and give rise to problems with memory and decision-making and depression. Though ALS doesn't affect intelligence and senses, some people may need help in their daily activities as their disease progresses.

Not all people can get ALS, those who have risk factors are more likely to acquire the disease. People who are more likely to acquire this condition include those are aged between 40 to 60 years of age, males, and those who have a family history of the disease. Experts say that ALS is due to a genetic defect in the enzyme superoxide dismutase 1 (SOD1) which further leads to motor neuron death. The symptoms of ALS may be vague but may include muscle cramping, twitching, muscle stiffness, muscle weakness, slurred speech and difficulty in chewing or swallowing. The body part affected is dependent on where the muscles of the body are damaged first. Symptoms may initially affect one leg and may affect gait, balance and coordination. If the muscles of the arm are affected, there may be difficulty in the performance of simple tasks such as buttoning a shirt, writing or turning a key in the lock. There may also be speech problems.

After the initial symptoms, muscle weakness and atrophy may spread to other parts of the body as the disease progresses. There may be problems with movement, swallowing, speaking and other problems. Upper motor neuron symptoms include stiffness and tightness of muscles and hypperreflexia. Abnormal reflexes such as the Babinski may be present. Lower motor neuron symptoms, on the other hand, include muscle weakness, muscle atrophy, muscle cramps and muscle twitching.

The Origin of Amyotrophic Lateral Sclerosis (ALS)

A new study has shown that amyotrophic lateral sclerosis may be caused by an error in protein formation. The study, done by researchers from University of Wisconsin-Madison, researchers have pointed out to proteins that build a transport structure inside the motor neurons. This structure, called the neurofilament, can move chemicals and cellular subunits to the far ends of the nerve cell. In ALS, there are tangles in the nerve's projections due to protein deformities that block the passage of signals in the nerve fibers and cause the malfunctioning and death of the neurons.

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