Guest Columnist: Christopher Cali
Last week, in response to the popular “ALS Challenge,” “Health & Exercise Forum” featured the four most common neurodegenerative diseases; amyotrophic lateral sclerosis (ALS), Alzheimer’s,(the most common form of dementia), Parkinson's and Huntington’s in an effort to raise the level of awareness and educate the public. This week in Part II, I invited Christopher Cali, who is currently pursuing his PhD in Genetics at the University of Pennsylvania, to discuss updates on these diseases as it relates to his research.
Neurodegenerative diseases, including; ALS, Alzheimer’s disease, (and various other forms of dementia), Parkinson’s and Huntington’s can take a devastating toll on patients and families. This broad category of diseases is characterized by the destruction of neurons that are important for memory and muscle function. It’s estimated that up to 50 million Americans currently suffer from a neurodegenerative disease, and this number is expected to grow as the Baby Boomer generation ages. The financial burden on society is huge as well. Dementia care alone is estimated to cost $250 billion dollars each year in the US. With the enormous mental, physical and societal burden of these diseases, scientists have made understanding neurodegenerative diseases a major priority.
As a graduate student at the University of Pennsylvania, I am working to understand the genetic basis of neurodegenerative diseases. My current work focuses on ALS (Amyotrophic lateral sclerosis, also called Lou Gehrig's disease) and a type of dementia called Frontal Temporal Dementia (FTD). ALS is a truly devastating disease that affects at least 30,000 Americans. It normally strikes otherwise healthy individuals between the ages of 30-70. The first symptoms are usually mild and arise as muscle weakness and/or stiffness. Symptoms become noticeable after frequent stumbles and difficulty lifting normal household objects. Slurred speech is also a common early symptom. The pace of this disease is relentless. Neurons that control every muscle in the patient’s body deteriorate over a few years, leaving patients unable to move anything except their eyes. Most patients live only 3-5 years after diagnosis. However, some patients do live for decades after diagnosis.
There is currently no effective treatment for this terrible disease. The medication riluzole is the only approved ALS medication, and it only extends life by an average of 3 months. As for prevention, some studies have suggested that diet and exercise can delay the onset of ALS symptoms or lessen the severity of symptoms in ALS patients. For instance, one study from the Harvard School of Public Health found that people with increased dietary intake of carotenoids (found in tomatoes, carrots and squash) had a slightly lower risk of developing ALS. It’s still debated whether regular exercise can reduce the risk of developing ALS. Some studies show that exercise is not a risk factor for developing ALS. Interestingly, a few studies report that ALS is more common among athletes and those with physically demanding jobs. While the role of exercise in prevention of ALS is unclear, it is certain that regular exercise and physical therapy after diagnosis can delay the decline of ALS patients.
Frontal temporal dementia is the second most common form of dementia behind Alzheimer’s. Like ALS, it typically occurs in middle aged people. It is characterized by drastic changes in behavior, inability to recognize objects or people, loss of organizational and planning skills and various speech problems. There is also no cure for FTD. So how are FTD and ALS connected?
In 2011, two research groups published the finding that a mutation in a single gene was responsible for both ALS and FTD in a subset of patients. This finding led to a wave of new research on these two diseases. Interestingly, this same mutation was found in small numbers of people with other neurodegenerative diseases, including Alzheimer’s. Scientists are now realizing that these diseases often overlap with each other, and it’s possible for one patient to have symptoms from several different neurodegenerative diseases. The recently discovered mutation lies in a gene that hasn’t been well studied at all. In fact, this gene is so new that it does not even have a name (it’s referred to as C9orf72).
Scientists are now beginning to understand how this newly identified mutation causes the disease and have already designed drugs that turn off the mutant gene. These drugs, called Antisense Oligonucleotides, are made up of short pieces of DNA that are injected into the patient and block the mutated gene. Since most ALS patients with the C9orf72 mutation have one mutated gene and one normal gene, shutting off the mutated gene should be enough to halt the disease. These drugs are currently being tested in mice with promising results.
Another promising piece of new technology that has been used to study ALS and FTD are cells called Induced Pluripotent Stem cells. Induced pluripotent stem cells are derived from adult skin cells and can be changed into any cell type in the body. For instance, the skin cell can be changed to a stem cell, and then to a nerve cell. This technology was developed by Shinya Yamanaka, who was awarded the 2012 Nobel Prize. The new procedure side steps the ethical issue of destroying a human embryo to obtain stem cells. It also allows scientists to grow personalized cells from patients that they can study in a dish and test new medications on. One day, scientists hope to be able to correct any genetic mutations in a patient’s cells and then inject the stem cells back into the patient’s spinal cord. In the right environment, they will change back into neurons and replace the diseased neurons.
There is still much to be done to fully understand ALS and FTD. The mutation in C9orf72 accounts for only a small percentage of all ALS patients. This means that there are numerous other genes that contribute to ALS that have not yet been identified. With today’s technology, however, it’s possible to go from an unnamed gene to a viable treatment in only three years. This should give those currently affected by ALS, FTD or any other neurodegenerative disease immense hope, as a cure may just be right around the corner.
Visit your doctor regularly and listen to your body.
Christopher Cali, received his BS in biology from Villanova University and is currently pursuing a PhD in Genetics from the University of Pennsylvania. To find out more about his work or donate directly to ALS research in his lab, visit: www.med.upen.edu/tnr
Chris, has strong local roots as a 2009 graduate of Scranton Prep and is the son of Dr. Gregory and Celeste Cali of Dalton.
NEXT MONDAY – Read Dr. Paul J. Mackarey “Health & Exercise Forum” in the Scranton Times-Tribune.
This article is not intended as a substitute for medical treatment. If you have questions related to your medical condition, please contact your family physician. For further inquires related to this topic email: email@example.com
Paul J. Mackarey PT, DHSc, OCS is a Doctor in Health Sciences specializing in orthopaedic and sports physical therapy. Dr. Mackarey is in private practice and is an associate professor of clinical medicine at The Commonwealth Medical College.