Regenerative Skincare

As humans, almost every cell in our body has been replaced countless times over the course of our lives, with a few key exceptions such as brain neuronal cells. The complex process of aging results in the gradual decline of the body’s metabolism and its ability to renew, repair, and regenerate, leading to compromised function which further hampers this capability, until the body is no longer able to sustain life.

The focus of the rapidly evolving field of regenerative medicine is, “to restore the functionality of tissues, organs, or body parts damaged by trauma, disease or aging.” Regenerative aesthetics is an offshoot of regenerative medicine, harnessing that emerging fields’ concepts to aesthetic ends. These fields are intertwined; advances in one have often led to advances in the other. Much of the rapidly proliferating armamentarium is the same

The search for identification of the component(s) in the circulation responsible for the "youthifying" of the older tissues has been active and has focused on stem cells, peptides, growth factors, mRNA, miRNA and other soluble biologically active molecules. There is palpable excitement about the newest component to be identified, exosomes, designated as EVs, that are being categorised and tested in pre-clinical studies as well as early clinical studies.

Twenty years ago, revolutionary skin care was introduced that contained the supernatant of a scaffold of cultured neonatal human fibroblasts, ushering in the “biologics” era in topical aesthetics. Over 110 active growth factors were identified, and the resulting skin care product was heralded as a breakthrough and is still in use today. Many tried to find the one or few growth factors that were the most important, but others argued it was the “physiologic” preparation that was responsible for the effects. But recently, it was found that this same product contained EVs, and that some of the effects seen with the product, which had been ascribed to growth factors, may have been due to EVs.

Multipotent stem cells were discovered by Till and McCulloch in 1961. The adult stem cell plays a key role in the maintenance and restoration of tissue and organs. Stem cells regulate all 4 phases of healing and repair: hemostasis, inflammation, proliferation and re-modelling. But stem cells accumulate DNA damage with aging resulting in impaired protein activity, cell function and normal organ physiology. A hallmark of aging is exhaustion of the endogenous stem cell population, resulting in a lessened ability to repair.

Also, stem cells are not abundant and are difficult grow in culture. They require a hypoxic (no air) environment to stave off differentiation. They must be extracted from tissues and kept frozen. Thus, in addition to the regulatory obstacles involved in their use, populations of stem cells are difficult and costly to obtain and maintain.

Exosomes (EVs) are typically, about 1/200th the size of the average cell, EVs are extracellular vesicles that occur through exocytosis (ie small bits that can escape from cells). Thought to be extracellular garbage at one time and now considered to be our information highway between tissues. Since EVs are used for cell-to-cell communication, it could be proposed that their contents, containing multiple different but physiological building blocks, are instructions to and material for the recipient cell, somewhat akin to a recipe.

Currently, 217 clinical trials related to EVs are listed on ClinicalTrials.gov, with 14 focusing on cutaneous concerns such as wound healing, atopic dermatitis, and melanoma, and only a few addressing aesthetic issues like laser healing, hair loss, and melasma. Despite frequent discussions about EVs in skincare and post-procedure contexts at dermatology conferences, meaningful data from diverse trials is needed for EVs to be fully integrated into aesthetic practices. There is no consensus on purity of preparations, optimal source(s), nor dosage or yield, let alone safety in humans. Although there are exciting possibilities based on preclinical studies and a few clinical studies, we are far from rigorous scientific studies that will reassure the practitioner that preparations with EVs are safe and effective for short or long term usage.

Not my own work. Taken from:

Taub AF. Regenerative topical skincare: stem cells and exosomes. Front Med (Lausanne). 2024 Oct 15;11:1443963. doi: 10.3389/fmed.2024.1443963. PMID: 39473496; PMCID: PMC11518787.