Effects of Repeated UVA Irradiation on Human Skin Fibroblasts Embedded in 3D Tense Collagen Matrix

Abstract

Skin photoaging is caused by cumulative UVA exposure that leads to dermal matrix alterations associated with impaired fibroblast functions. In this study, we evaluated the effects of repeated UVA irradiation on mechanically stressed fibroblasts which were embedded in 3D tense collagen matrix. By comparison to 2D monolayer culture, we investigated the expressions of alpha-smooth muscle actin (α-SMA) cytoskeleton and α2 subunit of integrin receptors, as well as the collagen metabolism, focusing to MMP-1 and collagen type-I expressions. We found that UVA exposure reduces collagen levels in both culture conditions. However, concerning integrin α2 and α-SMA expression, UVA irradiation had no effect on 2D culture, whereas in tense 3D culture, it had an inhibitory effect. In UVA-irradiated 3D culture, fibroblasts acquired elongated shape and lost their dynamic interaction with collagen fibers through a decrease in integrin α2 and α-SMA. Fibroblast responses to UVA irradiation were different in 2D versus 3D environment, highlighting the importance of collagen environment in the regulation of mechanical activities. The behavior of fibroblast upon mechanical stimulation closely mimics stressed extracellular environment. The model of UVA-irradiated fibroblasts cultured in tense 3D collagen gel illustrated the in vivo situation of both mechanically stressed and photoaged human skin.

Ceria Nanoparticles Decrease UVA-Induced Fibroblast Death Through Cell Redox Regulation Leading to Cell Survival, Migration and Proliferation

“…Ultraviolet A rays radiation has been associated with most of the dermal changes in photoaged skin resulting in impaired fibroblast functions (e.g., shortening life span, inability to proliferate and senescence) (Naru et al, 2005;Nakyai et al, 2018;Lan et al, 2019). CNP contributes to the healing process by inducing migration and proliferation.…”

A Frog Peptide Ameliorates Skin Photoaging Through Scavenging Reactive Oxygen Species

“…Collagen is derived from HSF cells and plays important role in maintaining the elasticity of skin ( Lee et al, 2012 ). Considering that antioxidin-NV has strong ability to restore the accumulation of a-SMA in hairless mice following UVB irradiation, and a-SMA is also a marker of myofibroblast which has a higher capacity to synthesize collagen ( Nakyai et al, 2018 ). We further investigated whether antioxidin-NV can promote collagen production in UVB-irradiated hairless mice.…”

Collagen and soy peptides attenuate contractile loss from UVA damage and enhance the antioxidant capacity of dermal fibroblasts

“…All data were expressed as the mean ± SD. 31 2.6 | UVA irradiation and human fibroblast treatment 14,15 HDF were seeded at a density of 5x10 4 cells/dish into 60 mm petri dishes and cultured for 24 hours in DMEM supplemented with 10% FBS, which was then followed by a 24 hours in serum-free DMEM containing the test compounds. After that the cells were washed twice with PBS, and covered with a thin layer of PBS.…”

“…After single UVA irradiation, HDF were extracted from the culture plates and embedded in the collagen lattice. [12][13][14][15] Collagen lattices were prepared using rat tail type I collagen (Gibco™, Invitrogen) dispersed in DMEM/10% FBS (pH adjusted to 7.4 with NaOH/ NaCO 3 ) containing pre-irradiated fibroblasts. These mixed solutions were placed into 60 mm culture dishes and then incubated at 37°C.…”

“…This 3D model can measure the effect of UVA on contractility of Human dermal fibroblasts (HDF) in culture. [12][13][14][15] Anti-photoaging substances have been widely used, including bioactive peptides that have been reported to regulate fibroblasts and control the production of ECM. 2 Bioactive peptides are inactive when they are part of the parent protein sequence, but become activated upon release by enzymatic processing, gastrointestinal digestion, food processing, or fermentation.…”