Neurodegenerative diseases refer to those conditions in which neurons in the brain, eye, and spinal cord undergo progressive degeneration and eventual death. In addition to immeasurable human suffering and caregiver burden, the economic impact of brain-related illness in the US alone has reached over $1.3 trillion of nondiscretionary healthcare spending. Since brain cells are rarely replaced by the body, sufferers of these diseases must cope with the loss of brain and body function for the rest of their lives. Neurodegenerative diseases, including Multiple Sclerosis (“MS”), Alzheimer’s disease (“AD”), Parkinson’s disease (“PD”), Amyotrophic Lateral Sclerosis (“ALS”), Huntington’s disease (“HD”), and Spinal Muscular Atrophy (“SMA”), target many distinct parts of the nervous system, but have the shared effect of slowly eliminating the ability to function and to care for oneself. The signature of many of these diseases is that their incidence increases with age. Because of this, the epidemic of neurodegenerative disease will continue to increase as life expectancy increases. Unlike many other major disease areas – infectious disease, cancer, cardiovascular disease, and psychiatric disease – the pace of drug development for neurodegenerative disease has been almost stagnant. There are very few approved drugs to treat neurodegeneration, and, in almost all of these cases, the approved treatments mitigate only the symptoms of the disease without addressing its underlying cause. The need for disease modifying therapies in neurodegeneration remains especially high, and it remains almost entirely unmet.
Neurons normally don’t reproduce or replace themselves, so when they become damaged or die they cannot be replaced. Neurodegenerative diseases are incurable and debilitating conditions that result in progressive degeneration and / or death of nerve cells. This causes problems with movement (called ataxias), or mental functioning (called dementias). The neurodegenerative diseases that the LDDN is currently focused on include:
- Amyotrophic Lateral Sclerosis (ALS)
- Alzheimer’s Disease
- Charcot Marie Tooth Disease
- Multiple Sclerosis
- Parkinson’s Disease
- Spinal Muscular Atrophy
Neurodegeneration refers to the malfunctioning or loss of specific cells (neurons) in the brain or spinal cord. When these cells do not function properly, the brain cannot, for example, learn new facts or signal the muscles in the body to move. The most common neurodegenerative diseases are Alzheimer’s, Parkinson’s, multiple sclerosis, amyotrophic later sclerosis (ALS), and Huntington’s. But neurodegeneration also happens as a result of a stroke, a blow to the spinal cord or head, or bleeding in the brain.
More than 100 billion neurons form a sophisticated network that constantly monitors and controls all of our voluntary actions (such as speech and movement) and automatic functions (such as memory, hearing, and breathing). When neurons are damaged, brain function is disrupted. For example, chemicals travel to and from cells acting as signals directing cells how to behave. Too much, too little, or the wrong ratios of these chemicals will damage cells. And when neurons die in large numbers, function is lost. In rare instances, neurodegenerative diseases are inherited, and scientists have identified several of the responsible mutations in various genes. But, in most cases, disease is triggered by a combination of genetic and environmental influences and, as a result, seems to appear randomly in the population. As we learn more about the inherited and environmental risk factors, we will be able to give individuals a better idea of their personal risk profile.