Research Paper Volume 11, Issue 6 pp 1619—1632
Cellular retinoic acid binding protein-II expression and its potential role in skin aging
- 1 Anatomic Pathology, Department of Biomedicine and Prevention, Tor Vergata University, Rome, Italy
- 2 Dermatology, Department of Internal Medicine, Tor Vergata University, Rome, Italy
- 3 Department of Clinical Science and Translational Medicine, Tor Vergata University, Rome, Italy
- 4 Department of Biomedical Sciences, Catholic University Our Lady of Good Counsel, Tirana, Albania
received: September 19, 2018 ; accepted: February 1, 2019 ; published: March 18, 2019 ;https://doi.org/10.18632/aging.101813
How to Cite
Copyright: Bielli et al. This is an open‐access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Skin aging is an intricate biological process consisting of intrinsic and extrinsic alterations of epidermal and dermal structures. Retinoids play an important role in epidermal cell growth and differentiation and are beneficial to counteract skin aging. Cellular retinoic acid binding protein-II (CRABP-II) selectively binds all trans-retinoic acid, the most active retinoid metabolite, contributing to regulate intracytoplasmic retinoid trafficking and keratinocyte differentiation. Immunohistochemistry revealed a reduced epidermal and dermal CRABP-II expression in aged human and mouse skin. To better clarify the role of CRABP-II, we investigated age-related skin changes in CRABP-II knock-out mice. We documented an early reduction of keratinocyte layers, proliferation and differentiation rate, dermal and hypodermal thickness, pilosebaceous units and dermal vascularity in CRABP-II knock-out compared with wild-type mice. Ultrastructural investigation documented reduced number and secretion of epidermal lamellar bodies in CRABP-II knock-out compared with wild-type mice. Cultured CRABP-II knock-out-derived dermal fibroblasts proliferated less and showed reduced levels of TGF-β signal-related genes, Col1A1, Col1A2, and increased MMP2 transcripts compared with those from wild-type. Our data strongly support the hypothesis that a reduction of CRABP-II expression accelerates and promotes skin aging, and suggest CRABP-II as a novel target to improve the efficacy of retinoid-mediated anti-aging therapies.