Characterizing Senescent Cell Burden in Skin
Researchers are delving into a more refined understanding of the burden of senescent cells in aging skin. Senescent cells accumulate in skin tissue as we grow older, due to a decrease in immune system efficiency and increased cellular stress. These lingering senescent cells emit pro-inflammatory signals, contributing to systemic inflammation associated with aging. Skin, being a significant organ, plays a crucial role in this age-related chronic inflammation.
Cutting-edge single-cell RNA sequencing and spatial transcriptomics techniques are shedding light on the cellular and molecular processes involved in skin aging and repair. Senescent cells, which cease to divide, can build up in skin over time due to various stress factors. Through detailed analysis, researchers have identified epidermal and dermal senescence, focusing on melanocytes and fibroblasts. Photoaging from UV exposure has been linked to higher levels of senescent cells, indicating accelerated biological aging compared to chronological aging.
A specific gene set called SenSkin, related to skin cellular senescence, has been identified as elevated in photoaging, chronological aging, and non-replicating CDKN1A+ cells. Senescent melanocytes in the epidermis show increased melanin production, potentially leading to irregular pigmentation. In the dermis, senescent fibroblasts are associated with reduced collagen and elastic fiber synthesis. Spatial analysis reveals clustering of senescent cells, especially in photoaged skin. This research offers insights into age-related skin issues through the lens of cellular senescence, highlighting the roles of senescent epidermal cells (melanocytes) and dermal cells (fibroblasts) in skin aging.
Link: https://doi.org/10.1111/acel.14358
