Perception gap of aged facial appearance; self-perception is younger than actual status due to angle of viewing.

Background: Facial morphology changes with aging, resulting in an aged appearance that is a great matter of concern for people. However, it is not clear whether people perceive their own facial appearance accurately, in part because there are few methods to evaluate this.

Aim: The aim of this study is firstly to establish an evaluation system for the perception gap of aged facial appearance between the self-perceived status and the actual status, and then to use this evaluation system to quantify the perception gap and to clarify the mechanism of this gap METHOD: Thirty-six middle-aged female volunteers were first asked to rate their facial aging-related morphology according to a 6-grade set of photos taken at a 45° angle from the front showing progressive stages of sagging severity, without looking either in a mirror or at photos of themselves (self- or "subjective" perception).

Subcutaneous fat infiltration into the dermal layer induces wrinkle formation.

Background: Wrinkles appear with aging, producing an aged impression, but the mechanism of wrinkle formation has not yet been fully elucidated. We recently reported that subcutaneous fat infiltrates into the dermal layer with aging and impairs skin elasticity, but the contribution of this process to wrinkle formation is still unclear.

Purpose: We aimed to clarify the contribution of dermal fat infiltration to wrinkle formation by analyzing the relationship between them in the forehead of female volunteers.

Vellus hair condition is related to dermal elasticity and facial sagging severity.

Background: Sagging of facial skin is a critical factor associated with an aged appearance. However, the mechanism of sagging has not been fully elucidated. The facial skin contains vellus hair (fine hair), but the contribution of vellus hair to skin condition and facial aging has yet to be studied.

Fat infiltration into dermal layer induces aged facial appearance by decreasing dermal elasticity.

Background: Facial morphology changes with aging, producing an aged appearance, but the mechanisms involved are not fully established. We recently showed that subcutaneous fat infiltrates into the dermal layer with aging, but it is not yet clear whether and how this drastic change of the dermal layer influences facial appearance.

Purpose: We aimed to establish the role of fat infiltration in producing an aged facial appearance and to clarify the mechanism involved.

Quantitative characterization of 3D structure of vellus hair arrector pili muscles by micro CT.

Background: Vellus hair is the fine, wispy hair found over most of the body surface, and the arrector pili muscles (hair muscle) serve to raise these hairs. Hair muscles are also critical for skin regeneration, contributing to the maintenance of stem cells in epidermis and hair follicles. However, little is known about their fundamental properties, especially their structure, because of the limitations of conventional two-dimensional histological analysis.

Infiltration of subcutaneous adipose layer into the dermal layer with aging.

Background: The elasticity of the dermal layer decreases with aging, leading to ulcer formation and wrinkling, but the mechanism of this change is not fully understood, because it is difficult to access the complex three-dimensional (3D) internal structure of the dermis.

Objective: To clarify age-dependent changes in the overall 3D structure of the dermal layer by means of 3D analysis technology.

Methods: We observed sun-protected human skin by means of X-ray micro CT, identified the layers of the skin, and reconstructed the 3D structure on computer.

Aging-related shift of eccrine sweat glands toward the skin surface due to tangling and rotation of the secretory ducts revealed by digital 3D skin reconstruction.

Background: Sweat gland function deteriorates with aging, leading to loss of heat tolerance. However, it is unclear whether and how the structure of sweat glands changes during aging, because the 3D structure is complex and inaccessible.

Methods: To clarify age-dependent changes in sweat glands, we developed a method for 3D structure analysis of sweat glands by means of X-ray micro-CT observation of human skin specimens followed by 3D digital reconstruction on computer (digital 3D skin).

Stanniocalcin-1 mediates negative regulatory action of epidermal layer on expression of matrix-related genes in dermal fibroblasts.

Dermal-epidermal interaction plays a role in many pathophysiological processes, such as tumor invasion and psoriasis, as well as wound healing, and is mediated at least in part by secretory factors. In this study, we investigated the factor(s) involved. We found that stanniocalcin-1 (STC1), a cytokine, is expressed at the basal layer of epidermis.

Senescent dermal fibroblasts negatively influence fibroblast extracellular matrix-related gene expression partly via secretion of complement factor D.

Aging is associated with a decrease of extracellular matrix and an increase of senescent cells in the dermal layer. Here, to examine whether and how senescent cells are involved in aging-related deterioration of the dermal layer, we cocultured dermal young fibroblasts (low-passage number) with senescent cells (high-passage number) in Transwells, in which the two cell types are separated by a semipermeable membrane. Young fibroblasts in coculture showed decreased collagen type I alpha 1 chain and elastin gene expression, and increased matrix metalloproteinase 1 (MMP1) gene expression.

Increment of subcutaneous adipose tissue is associated with decrease of elastic fibres in the dermal layer.

Obesity is a significant risk factor for various skin disorders, including pressure ulcer and delayed wound healing. We previously showed that increment of subcutaneous adipose tissue contributes to poor skin condition by decreasing dermal elasticity. Here, we examined the mechanism involved.

Involvement of upper cheek sagging in nasolabial fold formation.

Background: Nasolabial folds are a well-known feature of aging, but the mechanism of their formation remains unclear.

Objectives: To clarify the mechanism of nasolabial fold formation, we established grading criteria for severity and explored the influence of dermal elasticity and subcutaneous adipose mass. We also investigated the involvement of facial morphological changes, such as wrinkling and sagging.

Negative regulation of dermal fibroblasts by enlarged adipocytes through release of free fatty acids.

Subcutaneous adipose tissue lies just beneath the dermal layer, but the interaction between the two types of tissue remains obscure. Recently, we reported that obesity is associated with decreased dermal elasticity. To investigate the mechanism of the adipose tissue/dermal interaction, fibroblasts were cocultured with small or enlarged adipocytes, using a membrane insert to prevent direct contact.

Comparison of sagging at the cheek and lower eyelid between male and female faces.

Background: Facial sagging is a well-known morphological feature associated with aging and reduced dermal elasticity. Its morphological characteristics and mechanism have been studied in females, but it is unclear whether or not there is a gender difference.

Aims: The aim of this study was to clarify the morphological characteristics of sagging and the mechanism of sagging formation in male faces as compared with female faces, focusing on changes in dermal elasticity.

Rubus suavissimus S. Lee extract increases early adipogenesis in 3T3-L1 preadipocytes.

Leaves of Rubus suavissimus S. Lee (Rosaceae) are used to prepare tiencha or sweet tea, which is helpful for body weight control by restricting calorie intake in obese patients. Obesity is a risk factor for metabolic syndrome, and a possible approach to treatment is to promote early adipogenesis in adipose tissue, thereby leading to replacement of enlarged adipocytes that secrete inflammatory factors with small adipocytes.

Influence of subcutaneous adipose tissue mass on dermal elasticity and sagging severity in lower cheek.

Background: Subcutaneous adipose tissue lies just beneath the dermal layer, but the interaction between the two is not well understood. Recently, we showed that the subcutaneous adipose layer affects dermal properties in an obese rodent model.

Objective: To explore the influence of the subcutaneous adipose layer on dermal properties and morphology in humans.

The severity of wrinkling at the forehead is related to the degree of ptosis of the upper eyelid.

Background: Most studies on wrinkle formation have focused on changes in the dermal condition that promote the fixation of transiently formed wrinkles. Little is known about the age-dependent changes in transient wrinkle formation in response to altered facial expression or the mechanism leading to fixed wrinkle formation.

Objective: To clarify the mechanism of wrinkle formation at the forehead, we investigated the factors that influence the severity of transient wrinkling and the relationship of transient with fixed wrinkles, using a newly established method to evaluate transient wrinkle formation.

Increased subcutaneous adipose tissue impairs dermal function in diet-induced obese mice.

Increment of subcutaneous adipose tissue is a risk factor for facial morphological changes, such as sagging, which may be at least partly because of the increased weight burden of accumulated fat. However, it is not clear how the increase of subcutaneous adipose tissue affects dermal structure and function. We examined this issue in HR-1 hairless mice given a high-fat diet (HFD).

Heat stimulation reduces early adipogenesis in 3T3-L1 preadipocytes.

In this study, we used 3T3-L1 preadipocytes as a model to investigate the effects of heat stimulation on adipogenesis, which is a key process in the development of obesity. Heat stimulation at 43 degrees C for 60 min significantly reduced lipid accumulation, as measured by Oil Red-O assay. In the early phase of adipogenesis, heat stimulation almost completely blocked the increase of CCAAT/enhancer binding protein delta (C/EBPdelta) gene expression and delayed the onset of the increase of C/EBPbeta gene expression.

Adiponectin and leptin up-regulate extracellular matrix production by dermal fibroblasts.

Adipocytes were recently shown to secrete adipocytokines, such as adiponectin and leptin, which may have an endocrine role. Subcutaneous adipose tissue lies just beneath the dermis, and dermal condition is correlated with body mass index (BMI). However, it is not clear whether adipocytokines released by adipocytes in subcutaneous adipose tissue influence the adjacent dermis.