Alzheimer’s Disease: The Next Target for Umbilical Cord Blood Stem Cell Therapy?
Alzheimer’s disease and other forms of dementia are common afflictions among the elderly. They are known collectively as neurodegenerative diseases because they involve the gradual death of neurons in the brain. Sadly, there still is no effective treatment for Alzheimer’s and related diseases. However, umbilical cord stem cells could soon bring a wave of revolutionary new techniques for managing such degenerative disorders.
Alzheimer’s disease is caused by a loss of brain cells.
Alzheimer’s Disease is the most common cause of dementia in the world.1 Already it affects 5.4 million people in the United States and is the sixth leading cause of death among Americans.2 It is a slow, chronic disease which places an enormous time and financial burden on sufferers and family members who care for them.
The exact molecular causes of Alzheimer ’s disease are not entirely understood yet. What is known, though, is that over time, proteins start becoming formed incorrectly and aggregate in the brain. These aggregates, called plaques, cause inflammation and the death of neurons (brain cells). The death of more and more neurons leads to increasingly-severe symptoms of dementia, including memory loss, cognitive impairment, and emotional imbalance.3 Currently, the best therapies for Alzheimer’s Disease can slow neurodegeneration but cannot cure the disease or replace neurons that have already died.
Umbilical cord blood stem cells can regenerate neurons
Some stem cells, called neural stem cells, do exist in the brain. These are extremely slow to grow and divide, however, and they lose their regenerative capabilities with age. In cases of degenerative diseases, production of new neurons from neural stem cells cannot keep up with the neuron death rate.
This is where younger, healthier stem cells come in. Excitingly, stem cells obtained from umbilical cord blood from healthy newborn infants are capable of turning into neurons. These stem cells can regenerate neurons directly in the brain, and can form new synapses for healthy neural circuitry.4,5 They can also promote lower levels of inflammation, reduce the formation of abnormal proteins, and slow the loss of existing neurons.4,6
Animal models show promise of stem cells for Alzheimer’s disease
Before progressing to human clinical trials, stem cell therapy for neurodegenerative diseases must be extensively tested in animals first. To date, several animal studies have tested the safety and efficacy of injecting umbilical cord stem cells into the brains of mice and rats with neurodegeneration.
Laboratories studying neurodegenerative diseases have raised mice and rats which have a form of Alzheimer’s disease. Stem cells can be injected directly into specific areas of the brain, or into the carotid artery, which supplies blood to the brain and can deliver stem cells indirectly. These stem cells secrete proteins that support healthy synaptic function and reduce inflammation in the brain.7-9 Rodents that have received umbilical cord blood stem cells regain cognitive function, while the plaques in their brains are reduced.10
Early studies show stem cell therapy is safe for Alzheimer’s patients
In very recent years, a few small clinical trials have been conducted on stem cell therapy for human patients with Alzheimer’s disease.11 In one of these, umbilical cord blood stem cells were injected into the brains of nine patients. Over the two years of follow-up, no major adverse effects were reported. The use of these stem cells has been shown to be safe for use in people with Alzheimer’s.12 More extensive trials are planned for the near future to unveil the full potential for these stem cells to aid neuron regeneration and cognitive health.
1. Lane CA, Hardy J, Schott JM. Alzheimer’s disease. European journal of neurology. 2018;25(1):59-70.
2. 2016 Alzheimer’s disease facts and figures. Alzheimer’s & dementia : the journal of the Alzheimer’s Association. 2016;12(4):459-509.
3. Van Bulck M, Sierra-Magro A, Alarcon-Gil J, Perez-Castillo A, Morales-Garcia JA. Novel Approaches for the Treatment of Alzheimer’s and Parkinson’s Disease. International journal of molecular sciences. 2019;20(3).
4. Wang SM, Lee CU, Lim HK. Stem cell therapies for Alzheimer’s disease: is it time? Current opinion in psychiatry. 2019;32(2):105-116.
5. Yang S, Xue DD, Wu B, et al. Pleiotrophin is involved in the amniotic epithelial cell-induced differentiation of human umbilical cord blood-derived mesenchymal stem cells into dopaminergic neuron-like cells. Neuroscience letters. 2013;539:86-91.
6. Son M, Oh S, Park H, et al. Protection against RAGE-mediated neuronal cell death by sRAGE-secreting human mesenchymal stem cells in 5xFAD transgenic mouse model. Brain, behavior, and immunity. 2017;66:347-358.
7. Kim DH, Lee D, Chang EH, et al. GDF-15 secreted from human umbilical cord blood mesenchymal stem cells delivered through the cerebrospinal fluid promotes hippocampal neurogenesis and synaptic activity in an Alzheimer’s disease model. Stem cells and development. 2015;24(20):2378-2390.
8. Kim DH, Lim H, Lee D, et al. Thrombospondin-1 secreted by human umbilical cord blood-derived mesenchymal stem cells rescues neurons from synaptic dysfunction in Alzheimer’s disease model. Scientific reports. 2018;8(1):354.
9. Sanberg PR, Eve DJ, Willing AE, et al. The treatment of neurodegenerative disorders using umbilical cord blood and menstrual blood-derived stem cells. Cell transplantation. 2011;20(1):85-94.
10. Boutajangout A, Noorwali A, Atta H, Wisniewski T. Human Umbilical Cord Stem Cell Xenografts Improve Cognitive Decline and Reduce the Amyloid Burden in a Mouse Model of Alzheimer’s Disease. Current Alzheimer research. 2017;14(1):104-111.
11. Kang JM, Yeon BK, Cho SJ, Suh YH. Stem Cell Therapy for Alzheimer’s Disease: A Review of Recent Clinical Trials. Journal of Alzheimer’s disease : JAD. 2016;54(3):879-889.
12. Kim HJ, Seo SW, Chang JW, et al. Stereotactic brain injection of human umbilical cord blood mesenchymal stem cells in patients with Alzheimer’s disease dementia: A phase 1 clinical trial. Alzheimer’s & dementia (New York, N Y). 2015;1(2):95-102.