Oxytocin Levels Inversely Correlate With Skin Age Score and Solar Damage
December 2020 | Volume 19 | Issue 12 | Original Article | 1146 | Copyright © December 2020
Published online November 25, 2020
Nicole Hayre MD
Cosmetic Dermatology Center, McLean, VA
Studies have shown oxytocin (OT) and its carrier protein neurophysin 1 are found in the epidermis. The oxytocin receptor, which is found on human fibroblasts has been shown, when activated by oxytocin, to inhibit senescence-associated secretory phenotype (SASP). SASP activation induces the release of proinflammatory cytokines which contribute to skin aging. Therefore, its inhibition by oxytocin would constitute a protective mechanism. This pilot study was designed to explore clinical evidence of oxytocin levels correlating to the skin’s appearance in subjects. Methods:
Oxytocin levels, facial photographs, and lifetime sun exposure questionnaires from six female subjects aged 48–61 years old were analyzed. A skin age score (SAS) was determined for each subject and was compared to the expected average SAS for each subject based on their age to determine a percentage in change, if any. A reduction in SAS would indicate more youthful appearing skin than the average person of that age. Results:
All subjects had at least some reduction in SAS score as compared to their expected score. An almost linear relationship of SAS reduction as related to OT levels was found, showing a correlation of more youthful appearing skin with higher OT levels. Conclusions:
This study links previously published evidence of oxytocin’s protective role against inflammatory cytokine release in the skin with clinical evidence of OT levels correlating with SAS scores. Furthermore, it shows OT is likely inducing a protective function in the epidermis in the case of sun exposure and possibly with intrinsic aging. J Drugs Dermatol.
The epidermis has an obvious role of protecting us from the environment, but recent research is revealing some new functions. Keratinocytes have been shown to secrete oxytocin (OT) in response to an ATP analogue in a dose-dependent manner.1 Oxytocin is a neuropeptide which is involved with milk ejection, uterine contractions, behavior, memory, social bonding, and mental state.1,2,3,4 Oxytocin has also been shown to be involved with muscle regeneration, cardiovascular regulation, and osteocyte-adipocyte balance.4 In fact, both OT and its carrier protein neurophysin 1 are synthesized in keratinocytes.1
The oxytocin receptor (OTR) is a seven-membrane spanning receptor that is coupled via various G-protein isoforms to different signaling pathways, allowing it to have various physiologic functions in different cell types.2,5,6 The OTR is expressed on human fibroblasts.2,5 This receptor is internalized after binding with OT and is transported to the cell nucleus.5 Once in the cell nucleus, OT effects gene regulation.
Oxytocin binding to its receptor on fibroblasts has been shown to suppress senescence-associated secretory phenotype (SASP).4 When not suppressed, SASP promotes a low-level chronic inflammatory state by releasing proinflammatory cytokines such as interleukin (IL)-6, IL-1, chemokines, growth factors, and extracellular matrix-remodeling proteases.4 This leads to aging of the skin. Therefore, OT binding would have a protective, anti-inflammatory effect through its suppression of SASP and in turn its prevention of inflammatory cytokine release.4
This study attempts to establish a link between OT levels and clinical evaluation of the skin. Of interest, is whether or not a higher OT level correlates to more youthful appearing skin. Knowing that the appearance of the skin is not only due to intrinsic factors, we also evaluated the amount of lifetime sun exposure for each study subject as an indication of the amount of extrinsic or environmental aging.
A chart review was performed in an IRB-exempt study, revealing six female subjects aged 48–61 years old who qualified to be included. All were average BMI and non-smokers. Fitzpatrick skin types II–IV were included. Exclusionary criteria included any cosmetic procedures such as neurotoxin injections, dermal filler injections, chemical peels, laser treatments, or any other