A team of researchers from the Biomedical Research Institute (IRB Barcelona) and the National Center for Genome Analysis (CNAG) has made an exciting breakthrough in understanding the mechanisms of skin aging. Researchers Guiomar Solanas, Dr. Salvador Aznar Benitah and Dr. Holger Heyn discovered the key role of the IL-17 protein in the skin aging process, revealing the IL-17-mediated aging pathway and highlighting it. its relation to the inflammatory state [1].
Longevity.Technology: Aging skin undergoes a series of gradual structural and functional changes that contribute to its deterioration and fragility. As we age, the skin’s ability to regenerate decreases, the ability to heal wounds weakens, and the skin’s barrier function weakens. Understanding the cellular and molecular processes underlying these changes is critical to developing effective strategies to reduce the adverse effects of aging on the skin.
The findings of this study, published in the journal Aging of Nature, provide insights into the structural and functional changes that occur in aging skin and identify how some skin immune cells express high levels of IL-17, insights that may open new avenues for therapeutic interventions.
“Our results show that IL-17 is involved in various functions related to aging,” explains Dr. Aznar Benitah, ICREA researcher and head of the IRB Barcelona Stem Cell and Cancer Laboratory. “We found that blocking the function of this protein slows down the appearance of various defects associated with skin aging.” This discovery opens up new possibilities for treating some symptoms or facilitating skin recovery after surgery, for example [2].
“Single cell sequencing allowed us to dive deep into the complexity of the cell types and states that make up the skin and how they change throughout life,” says Holger Heyn, Head of the CNAG Single Cell Genomics Laboratory. “We found not only differences in the composition of aging skin but also changes in cellular activity states. Immune cells, in particular, showed specific age-related profiles that we were able to pinpoint by analyzing thousands of individual cells one by one. [2].
In addition to various types of epithelial cells and hair follicle cells, the skin also contains immune cells that play a vital role in preventing infection and protecting against damage. The study describes how, during aging, some of these immune cells, namely gamma delta T cells, innate lymphoid cells, and CD4+ T cells, increase dramatically in the skin, and these cells also begin to express very high levels of the pro-inflammatory cytokine IL-17.
Dr. Paloma Solá, the first author of this article, along with Dr. Elisabetta Mereu, is now a researcher at the Josep Carreras Leukemia Research Institute. She explains: “Aging is associated with mild but persistent inflammation, and in the skin, this is characterized by a large increase in IL-17, which contributes to skin deterioration. [2].
Previous studies have linked IL-17 to autoimmune skin diseases such as psoriasis, and treatments that block this protein already exist. In this study, researchers investigated the effects of blocking IL-17 activity on several aspects of skin aging, including hair follicle growth, transepidermal water loss, wound healing, and genetic markers of aging. Blocking IL-17 improved all four parameters, significantly delaying the onset of signs of aging. [1].
Dr. Guiomar Solan, associate researcher at IRB Barcelona, ​​points out: “The IL-17 protein is essential for vital body functions such as defense against microbes and wound healing, so it would not be possible to block it permanently. We have observed that its temporary inhibition confers benefits that may be interesting at a therapeutic level [2].
The researchers’ future studies will focus on the elimination of aging processes associated with skin inflammatory conditions and how they are related to IL-17. In addition, they aim to investigate whether IL-17 is involved in the aging and deterioration of other tissues and organs. These efforts will provide deeper insights into the complex interplay between IL-17, inflammation, and the aging process, potentially leading to new avenues for therapeutic interventions.