Development of a novel in vitro strategy to understand the impact of shaving on skin health: combining tape strip exfoliation and human skin equivalent technology

Introduction: The removal of unwanted hair is a widespread grooming practice adopted by both males and females. Although many depilatory techniques are now available, shaving remains the most common, despite its propensity to irritate skin. Current techniques to investigate the impact of shaving regimes on skin health rely on costly and lengthy clinical trials, which hinge on recruitment of human volunteers and can require invasive biopsies to elucidate cellular and molecular-level changes. Methods: Well-characterised human skin equivalent technology was combined with a commonplace dermatological technique of tape stripping, to remove cellular material from the uppermost layer of the skin (stratum corneum). This method of exfoliation recapitulated aspects of razor-based shaving in vitro, offering a robust and standardised in vitro method to study inflammatory processes such as those invoked by grooming practices. Results: Tape strip insult induced inflammatory changes in the skin equivalent such as: increased epidermal proliferation, epidermal thickening, increased cytokine production and impaired barrier function. These changes paralleled effects seen with a single dry razor pass, correlated with the number of tape strips removed, and were attenuated by pre-application of shaving foam, or post-application of moisturisation. Discussion: Tape strip removal is a common dermatological technique, in this study we demonstrate a novel application of tape stripping, to mimic barrier damage and inflammation associated with a dry shave. We validate this method, comparing it to razor-based shaving in vitro and demonstrate the propensity of suitable shave- and skin-care formulations to mitigate damage. This provides a novel methodology to examine grooming associated damage and a platform for screening potential skin care formulations

Cell Senescence-Independent Changes of Human Skin Fibroblasts with Age

Skin ageing is defined, in part, by collagen depletion and fragmentation that leads to a loss of mechanical tension. This is currently believed to reflect, in part, the accumulation of senescent cells. We compared the expression of genes and proteins for components of the extracellular matrix (ECM) as well as their regulators and found that in vitro senescent cells produced more matrix metalloproteinases (MMPs) than proliferating cells from adult and neonatal donors. This was consistent with previous reports of senescent cells contributing to increased matrix degradation with age; however, cells from adult donors proved significantly less capable of producing new collagen than neonatal or senescent cells, and they showed significantly lower myofibroblast activation as determined by the marker α-SMA. Functionally, adult cells also showed slower migration than neonatal cells. We concluded that the increased collagen degradation of aged fibroblasts might reflect senescence, the reduced collagen production likely reflects senescence-independent processes

'Holding on' and 'letting go': a thematic analysis of Australian parent's styles of coping with their adult child's methamphetamine use

Background: Although it is well established that parents can be negatively impacted by their child’s methamphetamine use, there is little research on how parents cope. This study aimed to explore the coping styles of Australian parents contacting an online counselling service concerned about their adult child’s methamphetamine use. Method: A thematic analysis of online counselling transcripts was used to examine key coping styles employed by parents (n = 26) who were seeking support in relation to their adult child’s methamphetamine use. Results: Two primary coping styles were identified. Parents were ‘holding on’ by trying to control and change their adult child’s methamphetamine use in order to improve the adult child’s circumstances and their own; or they were ‘letting go’ by releasing control to their adult child in the hope that over time they would reduce their drug consumption or seek help. While ‘holding on’ had benefits in terms of parents feeling as though they had some power to change their adult child’s situation, it also involved considerable ongoing stress and strain. ‘Letting go’ was often a source of grief, but for some parents, it enabled them to focus on self-care and their own wellbeing. Conclusion: This study highlights the potential value of treatment services tailoring the support they provide based on parents coping styles and preferences

The vitamin A ester retinyl propionate has a unique metabolic profile and higher retinoid‐related bioactivity over retinol and retinyl palmitate in human skin models

Human skin is exposed daily to environmental stressors, which cause acute damage and inflammation. Over time this leads to morphological and visual appearance changes associated with premature aging. Topical vitamin A derivatives such as retinol (ROL), retinyl palmitate (RPalm), and retinyl propionate (RP) have been used to reverse these changes and improve the appearance of skin. This study investigated a stoichiometric comparison of these retinoids using in vitro and ex vivo skin models. Skin biopsies were treated topically to compare skin penetration and metabolism. Treated keratinocytes were evaluated for transcriptomics profiling and hyaluronic acid (HA) synthesis and treated 3D epidermal skin equivalents were stained for epidermal thickness, Ki67, and filaggrin. A retinoic acid receptor‐alpha (RARα) reporter cell line was used to compare retinoid activation levels. Results from ex vivo skin found that RP and ROL have higher penetration levels compared to RPalm. RP is metabolized primarily into ROL in the viable epidermis and dermis whereas ROL is esterified into RPalm and metabolized into the inactive retinoid 14‐hydroxy‐4,14‐retro‐retinol (14‐HRR). RP treatment yielded higher RARα activation and HA synthesis levels than ROL whereas RPalm had a null effect. In keratinocytes, RP and ROL stimulated similar gene expression patterns and pathway theme profiles. In conclusion, RP and ROL show a similar response directionality whereas RPalm response was inconsistent. Additionally, RP has a consistently higher magnitude of response compared with ROL or RPalm