The Role of Stem Cells in Anti-Ageing
Stem Cells are the essential building blocks from which all tissues and organs of the human body are derived. They have the unique ability to regenerate and rejuvenate by replacing damaged cells.
Stem cells are found primarily in organs where cells are lost and replaced at high rates, such as the blood-forming bone marrow, gut, and skin/hair, all organs contain these organ-specific cells, even the brain.
Most stem cells are dormant. When damage occurs, cytokines and micro-vesicles released by damaged tissues can trigger them into action.
Mesenchymal Stem Cells
Mesenchymal Stem Cells (MSCs) are a particular type of adult stem cells that are easy to harvest from the subcutaneous fat or bone marrow. They are less controversial than embryonic stem cells. MSCs are currently seen as a useful therapeutic source for many pathological conditions and disorders. These cells are a core bio-factor in skin regeneration, muscle, cartilage, and bone regeneration.
The restorative, anti-inflammatory, and immunomodulatory qualities of stem cells have been shown effective for the treatment of a wide range of pathological conditions, including cardiovascular and neurologic diseases, such as stroke, spinal cord injuries, and Parkinson’s disease; autoimmune diseases such as multiple sclerosis and systemic lupus erythematosus as well as the healing of wounds and the repair of cartilage defects in osteoarthritis.
Over the past few years, particular focus was put on using stem cell-based therapies in urology, especially for treating erectile dysfunction. Many preclinical studies have explored the utility of Bone Marrow Stem Cells (BMSC) and Adipose-Derived Stem Cells (ADSCs), in particular, for treating ED in animal models.
Mesenchymal Stem Cells Slow Ageing by Reducing Inflammation
“Inflame-ageing” describes pro-inflammatory processes that promote ageing. There is evidence that high levels of circulating pro-inflammatory cytokines, such as TNF-α, interleukin-6 (IL-6), and C-reactive protein (CRP), even in “healthy” elderly individuals, are independent predictors of mortality.
High TNF-α, IL-6, and CRP levels correlate with decreased mobility, reduced muscle mass and strength, a weaker immune system, and impaired cardiovascular, pulmonary, and neurologic function. Elevated levels of these cytokines thus correlate strongly with early mortality and various causes of death.
Inflammation and Ageing
An increase in systemic inflammation illustrates a fundamental aspect of the ageing process. It is known that MSCs reduce the expression of pro-inflammatory cytokines, including TNF-α, interleukin (IL)-1 α, IL-6, and CRP. The paracrine effects of MSCs are produced in response to either secretion of a wide array of individual factors, such as growth factors and cytokines, or via exosomes, small extracellular vesicles that contain peptides, proteins, and microRNAs (miRNAs).
Factors secreted by MSCs include transforming growth factor (TGF)-α, hepatocyte growth factor (HGF), and interleukins, among many others. Many of these factors interact to produce an immunomodulatory effect78. MSCs also affect the immune system by releasing exosomes, which are 40–100 nm extracellular vesicles. Ex vivo studies have demonstrated that MSC-derived exosomes reduce the secretion of pro-inflammatory cytokines (IL-1ß, TNF-α) and increase the production of TGF-ß by PBMCs, but do not affect peripheral blood mononuclear cell proliferation.
Administration of MSCs or MSC-derived exosomes reduces the immune response in two mouse models of autoimmune disease, Type 1 diabetes mellitus and uveoretinitis.