Multiple sclerosis is a disease that affects the nerves. Nerves are encased by a protective layer called the myelin sheath. In individuals with multiple sclerosis, the body’s immune system mistakenly attacks and damages the myelin sheath, damaging the nerves inside and potentially creating scar tissue.
This damage and scar tissue interrupts the messages sent to and from the brain along the nerves. A variety of symptoms can result from this, such as:
- Muscle weakness or spasms
- Double or blurred vision
- Trouble remembering or focusing
- Trouble walking
There is currently no cure for multiple sclerosis. Today’s treatments focus on symptom management, slowing the disease’s progression, and speeding recovery after attacks. Hundreds of studies are conducted worldwide, funded by tens of millions of dollars, to find better ways to treat multiple sclerosis, perhaps even cure it. Several of the potential treatments being studied focus on utilizing naturally-occurring substances, like stem cells.
Placental stem cells might someday be used to treat multiple sclerosis.
Stem cells are undifferentiated cells that are able to differentiate in to specialized cells, such as skin or bone cells. Stem cells are present in adults, embryos, the umbilical cord, and the placenta. Adult stem cells are thought to be somewhat limited in their ability to differentiate into different cells, and harvesting them from bone marrow requires the use of a large and painful needle. The umbilical cord has a limited number of stem cells. The use of embryonic stem cells, which are harvested from aborted fetuses or discarded test-tube embryos, is highly controversial.
The placenta, however, is a plentiful source of non-controversial stem cells. In a study recently published in the journal Multiple Sclerosis and Related Disorders, researchers used placental stem cells to treat multiple sclerosis. They cultured, or grew, placental stem cells into PDA-001 cells. PDA-001 cells function similarly to the mesenchymal stromal cells, which aid in regulating the immune system.
After one year, magnetic resonance imaging (MRI) scans showed no worsening in the patients involved in the study. Most had either a stable or improved level of disability. Researchers are unsure how exactly the PDA-001 helps. It may become cells that produce the protective myelin sheath damaged by multiple sclerosis, or the PDA-001 cells may enhance the environment around damaged nerves to encourage natural repair.
Another study is looking at the effects of a naturally-occurring growth factor as a multiple sclerosis treatment.
Scientists at the European Molecular Biology Laboratory, located in Monerotondo, Italy, found that insulin-like growth factor-1 (IGF-1) dramatically increased the survival rate of animals with multiple sclerosis. Animals who were left treated had a survival rate of less than 50%, while those treated with IGF-1 had a survival rate of over 80%. The reason for this increased survival rate is the effect of IGF-1 on a group of cells called pro-inflammatory T-effector cells.
In people with autoimmune diseases, T-effector cells mistakenly identify specific bodily cells as foreign and attack them, just as invading bacteria would be attacked. The type of bodily cells attacked determines which type of autoimmune disease an individual has. For example, if the T-effector cells attack the pancreas, the individual will have type 1 diabetes. If the T-effector cells attack the myelin sheath surrounding the nerves, the result is multiple sclerosis.
Another type of cells, called T-regulatory cells, is supposed to control the T-effectors by shutting them down when they’re not needed. Scientists in this study found that mice receiving IGF-1 began to produce more T-regulatory cells. This suppressed the autoimmune disease.
This study is particularly promising because, in a study published earlier this year, the same researchers found that IGF-1 could suppress the inflammatory skin disease called allergic contact dermatitis in mice. The success in the previous study, in addition to the success in the current study, suggest that IGF-1 might be a viable treatment for a host of immune-related diseases. Additionally, IGF-1 is already approved for human use for other reasons, so clinical trials for its use in multiple sclerosis patients should move more quickly than if it was a brand new drug.
A natural molecule called NAD+ might also provide a potential treatment for multiple sclerosis.
NAD+ is found in living cells, plants, and food. Researchers in a new study found that NAD+ can alter the immune system’s response and convert harmful cells into protective cells. Specifically, NAD+ regulates how an immune cell called CD4+T differentiates. In addition to this, NAD+ is thought to activate stem cells that are already present, which could actually reverse or restore some of the damage caused by autoimmune diseases like multiple sclerosis.
Mice with a pre-clinical model of human multiple sclerosis were treated with the immune cell CD4+T when NAD+ was already present. Researchers saw a significantly delayed disease onset, in addition to a less severe form of the disease. Because of this treatment’s success and its ability to restore damaged tissue, the researchers hope that it may be a viable treatment option for many other different autoimmune diseases, in addition to multiple sclerosis. Since NAD+ occurs naturally, it’s hoped that treatments utilizing it will be tolerated well.
Parasitic worms might also hold the key to treating multiple sclerosis.
Helminthic therapy is the deliberate infection of an individual with worms, usually hook worms. This type of therapy is used to treat several autoimmune diseases, such as inflammatory bowel disease (IBD), Crohn’s disease, and multiple sclerosis. It’s thought that the worms lessen or calm the host’s immune system response, as a way of ensuring their own survival. Even if an individual is willing to be infected with parasitic worms, finding a physician to carry out helminthic therapy can be difficult.
Researchers in a study at Monash University identified a peptide called AcK1 from the anterior secretory glands of hook worms. This peptide is thought to be responsible for the suppression of the immune system by the worms. It functions by inhibiting a specific potassium channel. The next step for these researchers will be to find a way to develop a pill, so people with autoimmune diseases like multiple sclerosis can get the benefits of hook worms without actually being infected with them.
The AcK1 peptide from hook worms closely resembles a peptide from sea anemones, called ShK. The peptide from sea anemones has been shown to suppress autoimmune diseases, as well, and is already in clinical trials to treat multiple sclerosis.
Do you or somebody you know suffer from multiple sclerosis?
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