What is Amyotrophic Lateral Sclerosis?
Sometimes referred to as Lou Gehrig's disease, ALS is a terminal and rapidly progressive neurological disease that attacks the nervous system.
Neurons responsible for voluntary muscle movement deteriorate resulting in progressive weakness of the muscles and eventually paralysis.
On a Microscopic Level
In the normal functioning human body, motor signals originate in the brain and are delivered from motor neurons to a muscle via neuromuscular junctions.
The motor neurons and neuromuscular junctions within a person affected by ALS are broken down and therefore muscles are not stimulated.
Normal Neuromuscular Junction vs ALS Neuromuscular Junction
How It Happens
The enzyme, copper-zinc superoxide dismutase (SOD1), plays a crucial role in the cause of ALS.
SOD1's job is to protect cells from toxic metabolic waster by converting it into a nontoxic substance. It turns reactive oxygen into harmless water.
Research has linked a mutation of the SOD1 enzyme many cases of inherited ALS. Scientists have found that ALS is not developed due to a complete lack of the SOD1 in the body. Instead, the mutated enzyme gain a toxic property that is harmful to motor neuron cells.
Symptoms that are usually noticed first include:
- difficulty grasping/holding objects
- change in pitch of voice
- slurred speech
- occasional muscle twitches
Long Term Effects on the Body
Due to the crippling of motor neurons and neuromuscular junctions, the muscles of patients with ALS receive no stimulation. Muscles steadily weaken and the patient will no longer be able to move their voluntary muscles at all.
Normal Bicep Muscles vs ALS Affected Bicep Muscle
Familial or Sporadic?
Roughly 90% of patients with Lou Gehrig's disease are the only member of their family with it. Therefore, ALS is rarely a cause of genetics.
In cases of familial ALS, a parent with a mutated gene linked to ALS has a 50% chance of passing it down to their children.
Treatment Options - Medication
Medication given to ALS patients cannot reverse any damage but can slow progression of weakening muscles and making everyday life more comfortable.
Rilutek is the only medication available to ALS patients and is thought to work by decreasing levels of the chemical messenger, glutamate, that is present in the brain in high levels in ALS patients.
Treatment Options - Physical Therapy
Physical therapy for ALS patients consists of low-impact exercises of affected muscles in order to maintain strength for as long as possible.
ALS Patient Undergoing Physical Therapy
Along with physical therapy, patents may utilize braces or devices such as ventilators in order to maintain mobility and independence for the patient.
Outlook for Patients with ALS
A patient newly diagnosed with ALS are expected to live for 3-5 years following the diagnosis. However, it is not common for patients to exceed to 5 years and to live for even 10 years after diagnosis.
Death in ALS patients is almost always caused by respiratory failure and most patients die peacefully in their sleep.
"What Is ALS?" Emory ALS Center. Emory University, n.d. Web.
"How Do SOD1 Mutations Cause ALS?" CureFFI.org, n.d. Web.
"Symptoms and Diagnosis" About ALS. ALS Association, n.d. Web.
"Treatment" Amyotrophic Lateral Sclerosis. Mayo Clinic, n.d. Web.