Guion (2010) defines Amyotrophic lateral sclerosis (ALS) as “a progressive, heterogeneous, and neurodegenerative disease.” The disease is referred to as Motor Neuron Disease as it degenerates motor neurons in the brainstem, the spinal cord, or both (Miller, 2010). It affects the upper motor neurons in the brain and the lower motor neurons that are located in the anterior end of the spinal cord (Guion, 2010). In ALS, neurons degenerate and therefore cannot send messages to muscles. As a result, muscles weaken and twitch leading to failure in the movement of the legs, arms, and body. Eventually, the condition gradually worsens. The muscles in the chest zone fail making it difficult to breathe on oneself (Miller, 2010).
The common neurotransmitter involved in amyotrophic lateral sclerosis is the excitatory amino acid or glutamate (Müller 2008). Higher levels of glutamate have been found in the spinal fluid and serum in the ALS patients (National Institute of Neurological Disorders and Stroke, 2012). Laboratory studies have demonstrated that neurons are destroyed when they are considerably exposed to the glutamate (Müller, 2008). Another neurotransmitter involved in ALS is dopamine (Müller 2008). The number of dopamine neurotransmitters decline with age at varying rates throughout brain regions. The decrease in dopamine activity hinders the motor function and may also affect the performance of the frontal brain related tasks.
According to the National Institute of Neurological Disorders and Stroke (NINDS)(2012), there is no known cure for Amyotrophic lateral sclerosis, but various approaches are administered. One scheme is the use of physiotherapy to avert contraction of muscles and stiffness in joints. It can be done through exercises such as walking, stretching, and swimming. Similarly, devices such as wheelchairs are used to boost movement and independence. Speech therapists train ALS patients who experience speaking difficulties by making their patients try to speak louder. For those patients who cannot get sufficient nourishment from eating, feeding tubes are inserted into their stomach. The ALS patients, whose muscles that aid breathing weaken or fail, are given mechanical ventilator assistance which inflate and deflates the lungs. Finally, drugs such as Riluzole are also used (Mitsumoto, 2009). Riluzole decreases the release of glutamate, thus lessening the damage of the motor neurons (Miller, 2010).
The future direction for treatment of this disorder has been outlined by the National Institute of Neurological Disorders and Stroke (NINDS) (2012). Currently, researchers are studying the mechanisms that lead to the degeneration of motor neurons in order to find appropriate approaches that will stop the cell death. Studies are being conducted on animals to understand the ways in which SOD1 mutations contributes to the death of neurons. The large amount of free radicals that have been linked to ALS is also being researched. Additionally, scientists are studying how the loss of neurotrophic factors is involved in ALS. The discovery will lead to the creation of neuroprotective strategies. Neurotrophic factors play a significant role in the development, specification, maintenance, and protection of neurons in the spinal cord and the brain. Apoptosis is a process that gets rid of the body cells that are no longer useful. Scientists are seeking to understand the role of apoptosis in ALS and factors that trigger it. The findings would lead to the development of medical interventions for ALS. A biochemical abnormality (a biological marker) common to patients with ALS is yet to be discovered. Scientists are researching on it; and if successful, it will enable early detection and diagnosis of ALS. Researchers are also examining families affected with ALS who do not have the SOD1 mutation. The aim is to locate other genes that could be causing the disease. Scientists are optimistic that the above studies will lead to the discovery of drugs that will totally cure amyotrophic lateral sclerosis.