It is well known that ultraviolet rays cause photo-aging. Ultraviolet A (UVA) is the most important factor in photo-aging, especially in human dermis. As investigation of photo-aging in vitro, we previously reported that normal human dermal fibroblast (NHDF) was calcified by UVA irradiation. In this study, NHDF was cultured for one day after 0.8 J/cm2 UVA irradiation to investigate the influence of UVA irradiation, which calcifies cells. In addition, physiological and molecular biological changes on UVA irradiated NHDF were investigated. As a result, it was suggested that a significant oxidative stress was given to UVA irradiated NHDF, because accumulation of carbonylated proteins were observed in the cell. Moreover, it was elucidated that the intracellular Ca2+ mobilization indicated that an induction of inflammation was accelerating because of Ca2+ accumulation in the cell. Furthermore, it was suggested that calcification of UVA irradiated NHDF was involved in a decrease in cell survival rate. In molecular biological analysis, gene expression of PiT-1, Runx2, OCN and OPN which were well-known as osteogenesis marker on vascular smooth muscle cell (VSMC), were investigated on UVA irradiated NHDF using molecular biological method. As a result, increasing gene expression of PiT-1 and OPN was observed on UVA irradiated NHDF, although gene expression of Runx2 and OCN was not observed in the cell. From the results in this study, it was elucidated that NHDF calcified by UVA irradiation was involved in some significant damages, oxidation stress, calcium accumulation indicated inflammatory inducement in cells and decreased cell survival rate. On UVA irradiated NHDF, further investigation of physiological, biochemical, and molecular biological approach are required to determine the relationship between these physiological changes and calcification.
Various delivery techniques have been devised to improve the transdermal absorption efficiency of drugs. One of them is the microneedle method. Microneedles are technologies that improve the transdermal delivery efficiency of drugs by creating micropores in the stratum corneum using micrometer-sized needles. This technique is useful not only for drug development but also for cosmetic development. In recent years, development of various microneedles has been developed due to improvements in microfabrication technology. Japan’s R&D technology for microneedles is at a high level. In particular, in 2008, the world’s first microneedle cosmetics originated in Japan have been launched. This article outlines the characteristics of microneedles and introduces their application to cosmetics.
Recently open innovation between universities and industries has become more important system for cosmetic science in Japan. For this open innovation, joint research chairs in universities is available not only for industries but also for universities because of its propulsive force. Therefore, Mandom Corporation and Osaka University established the joint research chair in Osaka University in 2015. So far, we succeeded in isolation of sweat gland stem cells possessing the ability to regenerate sweat gland-like structures in vitro and visualization of the three-dimensional structure of the sweat gland, which regulates body temperature. Through these findings, we also succeeded in establishing an evaluation method for thermoregulatory sweat glands by visualizing and quantifying perspiratory contractions. In addition, quantifying the amount of sebaceous matter produced in human sebaceous gland and establishment of a new evaluation method were succeeded. Through collaboration with the National Institutes of Biomedical Innovation, Health and Nutrition, we confirmed for the first time in Japan that TRPM4, a cell sensor, controls inflammatory reactions in keratinocytes. In this review, brief summary of these research findings and explanation for benefits of join research chair are mentioned.
Although various tactile sensing systems have been developed, it is difficult to evaluate the tactile feel of cosmetics and cosmetic materials. We believe that the nonlinearity of the friction phenomena occurring on the surface of the skin is one of the causes of delicate touch texture. We have developed biomimetic materials that mimic the mechanical, surface properties and shapes of human fingers and skin. Next, we tried to elucidate the physical origin of tactile texture using the human finger model and artificial skin. Recently, a friction evaluation system that imitates the movement when a human touches things has been developed. In this system, nonlinear sinusoidal motion is achieved by the rotation of the motor with an eccentric cam. In addition, an in-situ observation type tactile sensing system is also used to simultaneously evaluate motion and mechanical stimulation when applying cream or touching powder. In this review, we introduce some recent studies on tactile sensing systems.
Regulations in the field of quasi-drugs and cosmetics have followed a completely different process. With the establishment of the Pharmaceutical Affairs Law in 1960, the regulatory system for quasi-drugs and cosmetics was united. Since then, the introduction of all ingredients, new cosmetic standards, etc. has been carried out. Consumer interest in quasi-drugs and cosmetics has become increasingly greater, driven by the recent increase in health awareness. In addition, for quasi-drugs and cosmetics, both inbound and outbound demand in the market is strong, and international distribution is progressing. Under these circumstances, the supply of high-quality and safe products is further demanded. In order to ensure the quality of ingredients blended in quasi-drugs and cosmetics and the safety of products, the Japanese government is reviewing the regulations as needed. This article outlines the transition of regulations in the field of quasi-drugs and cosmetics, with specific examples.
Cosmetic companies assure their cosmetic products based on national regulations and their own internal rules. The safety of cosmetic products consists of raw material safety and practical usage safety. Regarding the safety assessment of raw materials, local and systemic toxicological endpoints are based on market histories and existing data. When existing information is insufficient, safety tests have to be conducted. Many companies have abolished animal testing on cosmetics and raw materials. However, there are significant limitations in non-animal testing alternatives currently. After the safety of a raw material is assured, its safety in product form must also be assessed. When considering safety concerns regarding practical usage, all the influencing factors, such as age, sex, and sensitivity of the target population, have to be taken into account. Likewise, the period, frequency, and topical area of use must be taken into consideration. If the products show any safety concerns, product form tests should be conducted to further ensure their safety. When companies launch their products following safety assurance procedures, they should conduct post market surveys to monitor for any adverse events. If any such events occur, the company should evaluate the contents and take suitable actions. Further to this, in 2014, the Japanese government imposed the rule on companies that they must report each case of any severe adverse events related to cosmetic use. The safety of cosmetics has been well maintained by both the regulatory system and cosmetic company care and due diligence. However, more and more innovative products are being developed, with some causing severe and broad adverse events. Safety assessors should train themselves to keep their skills and knowledge up to date and companies should enhance their survey system to catch safety problems earlier.