Development of an Aged Full-Thickness Skin Model Using Flexible Skin-on-a-Chip Subjected to Mechanical Stimulus Reflecting the Circadian Rhythm

• Published in: International journal of molecular sciences Vol. 22; no. 23; p. 12788
• Main Authors: Jeong, Subin, Kim, Jisue, Jeon, Hye Mi, Kim, Kyunghee, Sung, Gun Yong
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 26-11-2021; MDPI
• Subjects: Aging; Bans; Biomarkers; Cells, Cultured; Circadian Rhythm; Circadian rhythms; Collagen; Compressive properties; Cosmetics; Drug development; Experimentation; Fibroblasts; Fibroblasts - cytology; Fibroblasts - physiology; flexible skin-on-a-chip; Galactosidase; Gene expression; Growth factors; Humans; Keratinocytes; Keratinocytes - cytology; Keratinocytes - physiology; Kinases; Lab-On-A-Chip Devices - statistics & numerical data; Mechanical stimuli; Metabolism; periodic compressive stress; Proteins; Secretion; Skin; Skin - cytology; Skin - metabolism; Skin Aging - pathology; Skin diseases; Thickness; Transcription factors; β-Galactosidase; flexible skin-on-a-chip; periodic compressive stress; circadian rhythm
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms222312788

The skin is subject to both intrinsic aging caused by metabolic processes in the body and extrinsic aging caused by exposure to environmental factors. Intrinsic aging is an important obstacle to in vitro experimentation as its long-term progression is difficult to replicate. Here, we accelerated aging of a full-thickness skin equivalent by applying periodic mechanical stimulation, replicating the circadian rhythm for 28 days. This aging skin model was developed by culturing a full-thickness, three-dimensional skin equivalent with human fibroblasts and keratinocytes to produce flexible skin-on-a-chip. Accelerated aging associated with periodic compressive stress was evidenced by reductions in the epidermal layer thickness, contraction rate, and secretion of Myb. Increases in β-galactosidase gene expression and secretion of reactive oxygen species and transforming growth factor-β1 were also observed. This in vitro aging skin model is expected to greatly accelerate drug development for skin diseases and cosmetics that cannot be tested on animals.