A 3D bioprinted in vitro full-thickness skin aging model

Area of Science:

• Biotechnology
• Tissue Engineering
• Dermatology

Background:

• Skin aging is a complex physiological process involving cumulative changes affecting skin function.
• Developing accurate in vitro aging skin models is challenging due to skin's multi-cellular nature and the cumulative aspect of aging.
• Existing models often fail to fully recapitulate the intricate dermal-epidermal junction of aged skin.

Purpose of the Study:

• To develop a novel 3D bioprinted skin aging model.
• To replicate key features of aged skin, including the dermal-epidermal junction.
• To validate the model's efficacy in recapitulating extrinsic aging and explore methods for inducing senescence.

Main Methods:

• Utilized a silk fibroin-gelatin bioink for 3D bioprinting a dual-layered skin model (epidermis and dermis).
• Employed senescent/late-passage fibroblasts and keratinocytes in co-culture, compared to early-passage cells.
• Induced aging conditions using oxidative stress (H2O2) and elevated glucose.

Main Results:

• The model successfully recapitulated aged skin attributes, showing reduced fibronectin and collagen I, II, and IV expression.
• Senescent cells in co-culture effectively mimicked aged skin characteristics compared to proliferative cells.
• High glucose exposure demonstrated greater potency in inducing aging phenotypes than H2O2.

Conclusions:

• The developed 3D bioprinted skin model accurately mimics key features of in vitro aged skin.
• This model serves as a valuable tool for aging research, disease modeling, and pharmaceutical screening.
• Elevated glucose is a potent inducer of aging phenotypes in this skin model, offering an alternative to traditional senescence induction methods.