Motor Neuron Disease: Early Signs, Types and Stem Cell Treatment
By R3 Stem Cell Pakistan
What are Motor Neuron Diseases?
Motor neuron disease refers to a collection of progressive disorders that affect motor nerves or neurons which control skeletal muscle movement. These diseases cause nerve cells to die, disrupting signal transmission from the brain to the muscle. It impairs the ability to move, speak, eat or even breathe.
Degeneration of motor neurons causes muscle weakness, leading to paralysis over time. Motor neuron disease can cause a considerable reduction in patients’ life expectancy. Motor neuron disorders are untreatable. Nonetheless, some therapies can help lessen the effects it has on a person’s everyday life.
Table of Contents
Types and early signs of Motor Neuron Diseases
The early signs of this degenerative disorder vary affect the individual level or person to person. This also depends on the type of motor neuron disease a patient is dealing with. Symptoms may begin on one side of the body and then extend to the other.
Motor neuron disease is a term that covers various disorders that can be caused by a combination of genetic factors, lifestyle, existing disease, and environment. However, most of these illnesses occur without any identifiable reason.
1. Amyotrophic Lateral Sclerosis (ALS)
Accounting for about 70% of all motor neuron disease cases, amyotrophic lateral sclerosis is the most common form of motor neuron disease. It primarily affects the muscle of the arms and legs. Stiffness, weakness, cramping, or twitching occurs along with other symptoms.
Sometimes physicians refer to ALS as “sporadic” which implies anyone can develop it between the ages of 40 and 60. A significant amount of patients only make up to 5 years of diagnosis. Recently, with the aid of modern treatments some patients are observed to have made significant improvements in life expectancy.
2. Progressive Muscular Atrophy (PMA)
Out of all motor neuron disease patients, about 10% are suffering from progressive muscular atrophy. People with PMA report weakness or sharp twinge of pain in their hands as their earliest symptoms. This is because PMA targets the lower motor neuron.
Mostly affecting women, this kind of motor neuron disease can be sporadic or hereditary. The symptoms still progress over time possibly implicating upper motor neurons. With a better life expectancy, PMA sometimes turns into ALS.
3. Primary Lateral Sclerosis (PLS)
Commonly diagnosed around the ages of 40-50, PLS is a rare variant of MND that accounts for about 1-2 % of all cases. The earliest signs of impairment are observed in the arms and legs including muscle tension, weakness, slow walking, and progressive deterioration in balance coordination.
Though not as morbid as ALS, primary lateral sclerosis has a significant advancement of symptoms affecting even the speech; which becomes slow and distorted. Many times, ALS patients are misdiagnosed with primary lateral sclerosis because of the similarities between both. However, it is uncommon for PLS to progress into ALS after 5 years of diagnosis
4. Progressive Bulbar Palsy (PBP)
Progressive bulbar palsy occurs in about 20% of all cases of motor neuron disease and eventually develops into Amyotrophic lateral sclerosis (ALS). Since most of the damage is caused in the brain stem, located at the base it affects the muscles of the tongue, mouth, and speech organs or bulbar muscles (pharynx and larynx).
Early symptoms include decay, frailty or stiffness of the tongue, difficulty with swallowing, speaking, chewing, and salivary issues. Often starting from bulbar muscles the symptoms progress to legs, hands, and arms
5. Pseudobulbar Palsy
Also known as the involuntary emotional expression disorder pseudobulbar palsy affects the bulbar including muscles of the face, mouth, and throat. Pseudobulbar palsy produces uncontrollable laughter or crying.
6. Progressive Muscular Atrophy
Occurring in about 10% of motor neuron disease patients, the lower motor neurons are primarily affected by progressive muscular atrophy. The primary symptoms usually start showing muscle weakness and spasms in the hands.
However, the progression of the disease can subsequently spread across all different muscles. PMA potentially progresses to amyotrophic lateral sclerosis. Men are more likely than women to be affected.
7. Spinal Muscular Atrophy (SMA)
Spinal Muscular Atrophy is a hereditary type of motor neuron disease. Early symptoms of SMA manifest in arms, upper legs, and torso. Set off by a mutated gene known as SMN1, SMA damages the lower motor neurons.
SMN1 produces a protein to protect motor neurons. Lack of it makes motor neurons vulnerable.
SMA is classified into several categories based on when symptoms initially appear.
Werdnig-Hoffmann disease or Type 1 at the age of 6 months children with spinal muscular atrophy are unable to sit or hold their heads up. Weak muscles, issues with breathing or swallowing, and slow reflexes are some of the primary symptoms.
TYPE 2 Generally occurs between the ages of 6 and 12. This type of SMA hinders the child’s walking and standing, sometimes even the ability to breathe.
Kugelberg-Welander disease or Type 3 begins between the ages of 2-17. It has an impact on a child’s ability to use their lower limbs. The patient may have a bent spine as well as shortened muscles or tendons surrounding their joints. Hindrance in standing up, walking, climbing, or running is often observed.
TYPE 4 After the age of 30, Muscle weakness, shaking, twitching, and breathing issues are all symptoms of this variety. Muscles in the upper arms and legs are particularly affected.
8. Kennedy's Disease
A rare genetic neuromuscular ailment that only affects men. Women can carry this mutated gene, with a 50% chance of transmitting it to offspring. Kennedy’s disease is characterized by gradual muscle weakness and atrophy, mainly in the arms and legs. Symptoms like tremors, twitching, weakness, and cramps in muscles of arms, face, and legs (sometimes throats too)
Can these Types of Motor Neuron Diseases be treated by Regenerative Medicine?
Motor neuron disorders are a set of diverse neurodegenerative diseases that are usually caused by unknown factors. Due to MND’s severity and rapid advancement, many treatments that might work for other diseases do not work for it.
Many clinical trials have proved regenerative medicine as an effective treatment for motor neuron damage. Stem cell therapy is a well-known and promising form of regenerative medicine that has the potential of treating and delaying the progression of MND.
Stem Cell Sources:
Cell-based therapy treats various diseases by injecting cellular material into the patient’s body. This cellular material can be obtained from different sources but the most promising in the case of motor neuron disease are umbilical cord stem cells and amniotic fluid stem cells.
How does Stem Cell Therapy help Neurodegenerative Diseases?
Stem cells are good at detecting damaged and inflamed sites. However, physicians recommend stem cells as a treatment due to their unique properties that can assist in treating different kinds of neurodegenerative diseases.
1. Multilineage Differentiation:
Stem cells can evolve into specialized classes of cells.
This quality alone makes them an excellent treatment. When introduced to a patient with motor neuron disease, stem cells travel to the site of damage and differentiate into cells or tissues that are damaged.
In patients with ALS/ MND, this feature helps in the regeneration of motor neurons and white blood cells. They maintain and repopulate the damaged tissues by integrating with them and enhancing neural repair improving the overall nervous system.
Neural improvement can back and fro messages from the Central nervous system to the rest of the body, leading to healthier and functioning muscles. Continual use of muscle eliminates the symptoms like slurred speech, Cachexia, twitching, and cramping.
Stem Cells are capable of replicating themselves. In the right environment, a small amount of harvested cells can multiply to great numbers.
Umbilical cord stem cells are recognized for rapidly multiplying into new daughter cells that can travel to damaged locations and treat them more effectively.
The motor neuron damage occurs swiftly across the body. This issue is treatable with rapid multiplication and differentiation of stem cells. Nerve cells can be regenerated, restoring the muscle’s ability to move.
Stem cells resist the immune system’s unfavorable responses and adapt to changes in the immune system.
This quality helps the overall environment of the body by improving cell to cell communication, preserving the existing and generating new motor neurons. Merging with the immune system promotes a non-tumorigenic response, which means stem cells regulate adaptive immune cells to prevent tumor growth.
Usually, people with ALS live up to around 3 years after diagnosis. However, stem cell treatment coupled with various rehabilitation practices like physiotherapy and proper diet can prolong life expectancy. Exercise has been observed to enhance cells’ mobilization and recruitment.
Both the clinical and preclinical evidence suggests that stem cell therapy is a verified treatment for ALS or MND. slows down the progression, improves the quality of life, increases survival and overall well-being.
Are there any side effects of Stem Cell Therapy?
Stem cell treatment has two aspects of performance.
– Slowing or stropping the disease progression
– Improving and regenerating the damaged tissues
However, it is also dependent on the environment in which it operates. If the environment is unpleasant, stem cells may not be able to improve the situation, but they stop the progression at all costs. Thus, the treatment might show its effectiveness gradually over the period of 2-6 weeks with no significant negative effects.