Stem cell numbers and function naturally decline with time, leading to organismal aging. Can regenerative stem cell therapies promote Longevity?
Aging is a complex process impacting, among other things, the organism’s ability to maintain homeostasis and regulate body functions. Thus, aging is associated with several age-related disorders, including diabetes, cancer, osteoporosis, arthritis, and several heart and neurodegenerative diseases. Efforts have been made to identify cell types involved in the process of aging; stem cells have undoubtedly been at the forefront of this research [1].
Stem cells are undifferentiated cells that can give rise to all specialised cell types of our bodies. They were first described in the early 1960s, and considering their self-renewal and regenerative properties, it did not take long to realise the important role of them in aging:
Cancer and aging appear to represent the failure or success, respectively, of vital tumour-suppressor mechanisms that rely on the activities of telomere shortening and the activation of the cyclin-dependent kinase inhibitor p16 and the tumour suppressor p53. Evidence suggests that these tumour-suppressor molecules exert pro-aging and anti-cancer functions in discrete compartments of self-renewing cells (tissue-specific stem cells) that are present in adult mammalian tissues.[2].
Stem cells act as a “cell backup system” for the living organisms to replace damaged or old cells, thereby enhancing their restorative potential. Different organisms have different regenerative power, and this can relate to the different numbers of stem cells in their bodies [3].
A widely believed theory describes aging to be a result of the disruption in the balance between the breaking down of tissue and tissue rebuilding. Stem cells promote life extension by replacing the damaged and old cells, and have, therefore, emerged as a powerful tool in the fight against aging. However, as the years go by, the quantity and function decline, until eventually, the old or damaged cells cannot be replaced, leading to aging. The use of regenerative therapies to reverse aging lies in the development of interventions that minimise the gradual decline in stem cell quantity and function, replace them, or boost the function of the remaining ones [3]. Proof-of-concept studies in mice involving the replacement of stem cells in the brain provided evidence of functional improvement of the aging brain [4, 5].
We recently covered AgeX Therapeutics and Lineage Cell Therapeutics being awarded a US patent for ‘Method of Generating Induced Pluripotent Stem Cells’. “This patent broadly describes multiple techniques for reprogramming cells of the body back to the all-powerful stem cell state,” said Dr Michael D West, CEO of AgeX and first inventor on the patent.
Regenerative medicine and stem cells have been the main focus of biomedical research in recent years and provided hope for the treatment of numerous human diseases. This is reflected in the fact that the market is expected to reach $297 billion in the next two years.
Despite the enormous potential of stem cells in fighting age-related disorders and promoting Longevity, further research is needed to fully understand the mechanisms underlying stem cell biology and how the regenerative capacity of them can be enhanced to promote a healthy and longer life before regenerative therapies can enter the Longevity marketplace.
[1] https://dev.biologists.org/content/143/1/3
[2] https://www.nature.com/articles/nrm2241
[3] https://stemcellres.biomedcentral.com/articles/10.1186/s13287-017-0746-4
[4] https://bit.ly/2Rp7NIy
[5] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5999038/
