It has been reported that normal human dermal fibroblasts (NHDF) are calcified by UVA irradiation. In the arterial calcification, it is well-known that the calcification of vascular smooth muscle cells (VSMC) is accompanied by the apoptosis induced by endoplasmic reticulum (ER) stress. From these findings, we considered that calcification by UVA irradiation is more likely to be caused by a similar mechanism to that of arterial calcification. This study aimed to investigate the relationship between the apoptosis induced by ER stress and the calcification caused by UVA irradiation. Molecular biological and cell physiological methods were used to achieve the aim in this study. As a result, the calcification and the activity of caspase-3, a mediator of apoptosis were suppressed by the ER stress inhibitor 4-phenylbutyric acid (4-PBA), in UVA-irradiated NHDF. Furthermore, in UVA-irradiated NHDF, upregulation of the expression of ER stress-induced apoptosis mediators were confirmed. It has also been reported that deep seawater (DSW) suppresses this calcification. Hence, the suppressive mechanism of DSW was investigated through the relationship between the apoptosis induced by ER stress and the calcification caused by UVA irradiation. As a result, DSW suppressed the caspase-3 activity and calcification, similar to 4-PBA. In addition, DSW reduced the expression of genes specific for ER stress-induced apoptotic pathway. To summarize these results, it was suggested as a possibility that the calcification of NHDF caused by UVA irradiation is accompanied by the apoptosis induced by ER stress, and DSW regulates ER stress-induced apoptosis.

Melanogenesis in melanocytes is regulated by various factors from nearby cells. In particular, inflammatory factors derived from epidermal cells have an influence on melanogenesis. Recent studies have shown that melanocytes are not only activated by mediators from epidermal cells but also mediators from dermal cells. Recent research reports show that the expression of HGF (hepatocyte growth factor) secreted from fibroblasts is increased in areas of solar lentigo and aging tissues. Therefore, HGF is thought to have an influence on excessive melanization. Thus, we investigated the influence of HGF secreted from fibroblasts on melanocytes and the inhibitory effect of a perilla extract on excessive melanogenesis caused by HGF in melanocytes. We chose the perilla leaf because it is known to contain polyphenols that show antioxidant activity and anti-inflammatory effects that contribute to a suppressive effect on inflammation. This suggested that a perilla leaf extract might well suppress melanogenesis.

We confirmed that UV-B irradiation increased HGF gene expression in cultured fibroblasts (NB1RGB) and that the perilla leaf extract had an inhibitory effect on HGF gene expression in cultured fibroblasts irradiated with UV-B light.

Furthermore, we investigated the influence on the proliferation of melanocytes and the transcription activity of STAT-3 in cultured human melanocytes (NHEMs) with and without the addition of HGF and perilla leaf extract. We confirmed that the proliferation of melanocytes and transcription activity of STAT-3 were increased when HGF was added to melanocytes. On the other hand, perilla leaf extract inhibited the increase in proliferation of melanocytes and transcription activity of STAT-3 induced by HGF. We also investigated other effects of perilla leaf extract, and we found that it had an inhibitory effect on tyrosinase activity.

In the in vivo study, we prepared a cream containing the perilla leaf extract, and application of the cream inhibited the pigmentation induced by UV-B in human skin.

In addition, we aimed to confirm the safety of perilla leaf extract by checking for toxicity to melanocytes. We applied the cream containing the perilla leaf extract to human skin twice per day for 2 weeks, and then irradiated the site with UV-B to induce pigmentation equivalent to that in the control area. The results showed that the perilla leaf extract did not exhibit toxicity in melanocytes. In conclusion, we developed an original perilla leaf extract as a functional natural material that inhibits the stimulation of melanocytes via fibroblasts.

The presence of skin microbiome on the surface of the skin and their involvement in the host immunological homeostasis and in the pathogenesis of inflammatory skin diseases is becoming elucidated. Staphylococcus aureus (S. aureus) has long been known to colonize the skin of patients with atopic dermatitis (AD), but its involvement in the pathogenesis of the disease was unknown. Recent studies have shown that AD patients experience a disruption of the bacterial balance (dysbiosis), in which the diversity of the microbiome decreases and the number of S. aureus increases during flare, and that this may contribute to the worsening of the dermatitis. Several S. aureus-targeted therapies have been developed and have shown some efficacy on AD.

To examine how the COVID-19 pandemic has transformed consumer awareness, we conducted an analysis of the results of user surveys and reviews on @cosme.

We found that consumers have become more cautious in their consumption and tend to be attracted to product safety and reliability as compared to before the COVID-19 pandemic. Products that have been popular for a long time, such as long-selling products and relaunched products, are favored. Consumers who have become more cautious also have a stronger desire to try products before purchasing them.

In addition, there has also been a trend of consumers using cosmetics to inject a change of pace into their daily life (which has become more restricted), and selecting cosmetics that make them feel more connected to the rest of the world.

It is no exaggeration to say that masks have had the greatest impact on post-COVID beauty trends, and around half of the respondents still express frustration at their makeup not lasting under masks. In view of the fact that many people probably have not found a product that does not adhere to their mask, it is vital for manufacturers to cater to them.

On the other hand, despite their dissatisfaction with masks, half of the respondents indicated that they believe wearing masks improves their appearance and the impression they give and that they are sometimes afraid to remove their mask and show their face.

To brace ourselves for the eventual day when people can remove their mask, there is a greater need than ever moving forward to find ways to make people feel more comfortable with presenting their face without a mask and to achieve a balanced and natural look, as well as a need for makeup techniques and skincare approaches that address the areas of the face that are hidden beneath masks.

With COVID-19 pandemic, video conference systems and SNS have become more widespread. It has become common to communicate with people through digitized faces. On the other hand, we were required to wear a mask when communicating face-to-face. With the spread of new facial styles such as remote faces on displays and real mask faces, make-up has changed significantly. In this paper, we consider the role of makeup in present day, focusing on the effects of new facial styles on makeup. We also consider the issue of face and identity in the modern era of expanding virtual reality.

Fragrances have long been reported to have an effect on psychological stress and fatigue. In recent years, studies that have demonstrated the effects of fragrances by scientific methods have also been reported. On the other hand, research has also been conducted for many years on the question of how to objectively assess fatigue and psychological stress. If fatigue cannot be found and it becomes a serious condition if the individual and those around him or her are unaware of it. It is possible to develop methods to objectively evaluate the amount and degree of fatigue and express it numerically. This paper first describes the evaluation methods of fatigue and psychological stress, and then outlines how the effects of fragrances on fatigue and psychological stress should be evaluated, as well as the problems and future direction of these evaluation methods.

The aim of this lecture series is to provide basic knowledge on skin troubles induced by cosmetics, as well as usefulness of cosmetics on skin disorders. Articles of this series, described by expertized dermatologists and planned for three years, will include various aspects of skin troubles of cosmetics and use of cosmetics by subjects with troubled skin. I hope that this lecture series will be helpful, not only for cosmetic scientists, but also for clinical dermatologists.

For those who deal with cosmetics, it is recommended to know the normal structure and function of the skin to ensure safe and effective use of cosmetics and cosmetological treatments. The skin is not just a membrane that separates the human body from the outside but has various functions for maintaining homeostasis of the human body. In this paper, we have outlined the normal structure of the skin, touching on the pathological structures related to cosmetology.

The skin consists of three layers: epidermis, dermis, and subcutaneous fat. The epidermis contains four layers: horny layer, granular layer, spinous layer, and basal layer. The horny layer plays a major role of barrier function at the forefront. When the stratum corneum is deficient in intercellular lipids, horny cells become compact and their water retention function is reduced, resulting in “asteatotic eczema,” which is a very common pruritic skin lesion in elderly. With aging, elastic fibers are denatured by long-term exposure to ultraviolet rays, and cause solar elastosis resulting in deep wrinkles. As skin appendages of the dermis, there are hair follicles, sebaceous glands, and sweat glands, which are sites of androgenic alopecia, acne, hyperhidrosis, and osmidrosis, respectively, and exhibit morphological and functional changes. All pathological conditions treated cosmetologically are closely associated with changes in skin structure and function.