Stiffness measurement is a biomarker of skin ageing in vivo

Abstract

Due to the expansion of the ageing population, understanding age-related pathologies remains of great interest. The human skin is particularly affected by environmental stressors and goes through profound alterations that modify its appearance throughout ageing (for review, [1]). These modifications occur in the epidermis that becomes thinner due to reduced capacities in proliferation/differentiation, resulting in reduction of exchange surface. The alterations also arise in the dermis where the number of fibroblasts declines, leading to a decrease in collagen and elastin fibres of the extracellular matrix. This process of reduced proliferation abilities of cells including keratinocytes in the epidermis and fibroblasts in the dermis is mainly due to cellular senescence. These modifications are due to chronologically intrinsic ageing, which can also be amplified by extrinsic factors such as solar UV radiation. Even if the molecular mechanisms underlying human skin ageing are increasingly understood, it remains essential to understand skin homeostasis and its perturbation during ageing process in an integrated view.

The Human Epidermal Basement Membrane: A Shaped and Cell Instructive Platform That Aging Slowly Alters

“…ECM produced by and surrounding papillary dermis fibroblasts undergoes profound alterations during skin aging. The curled, thin, short, and loosely interwoven fibers become thicker and form network aggregates [253][254][255][256], leading to assessable changes in the overall tissue stiffness [257]. These changes are more severe in photo-exposed skin [242,254].…”

More than just bricks and mortar: Fibroblasts and ECM in skin health and disease

“…Depending on its biomechanical properties, ECM can profoundly impact fibroblast survival, proliferation, migration and inflammatory signalling 14 . Thus, approaches that measure biomechanical skin properties across scales ranging from single‐cell to whole‐tissue can educate skin disease diagnosis 15 and serve as a biomarker of skin ageing 16 . Yet, the effects of ECM on fibroblasts are reciprocal, and the latter can significantly alter ECM biomechanics via contractility.…”

Eggshell membrane promotes homeostasis of elastic skin and lung tissue associated with type III collagen and decorin expression and ameliorates pulmonary fibrosis in a bleomycin mouse model

“…In addition, this study showed that human consumption of ESM powder as a dietary supplement can produce ECM effects such as skin elasticity and improved respiratory function. Since skin aging is characterized by structural and functional changes such as wrinkles and loss of elasticity, and skin stiffness reflects reorganization of the ECM in the dermis (Runel et al 2020), mechanical properties and functional changes in the skin and lungs by ESM ingestion may indicate a shift to a younger ECM.…”