Isoflavones in the Prevention of Photoaging: Antioxidant and Collagen-Regulating Mechanisms—An Integrative Review
TL;DR
The findings showed that isoflavones effectively decreased ROS and MMPs activity, and increased COL1A1 expression in both in vitro and in vivo models, which translated to human-level benefits, as clinical trials showed improved hydration, elasticity, and decreased wrinkles.
Abstract
Skin aging due to ultraviolet (UV) light exposure, known as photoaging, is a form of extrinsic aging characterized by increased oxidative stress, collagen degradation, and structural changes in the dermis. Chronic UV exposure triggers the formation of reactive oxygen species (ROS), activation of matrix metalloproteinases (MMPs), inflammation, and decreased tissue regeneration. Soy isoflavones, as natural phytoestrogens, offer potential as antiphotoaging agents through potent antioxidant mechanisms and stimulation of collagen biosynthesis. This article aims to explore the scientific evidence regarding the potential of soy isoflavones, especially genistein and daidzein, in preventing and repairing skin damage due to photoaging. Although isoflavones are known to be antioxidants, integrative studies comparing their effects based on biological models are limited. A systematic literature search was conducted on three major databases (PubMed, Google Scholar, and Semantic Scholar) using the following keywords: soy isoflavone, photoaging, collagen, and MDA. Selection followed the PRISMA flow, from which eight articles were selected for thematic analysis. The findings showed that isoflavones effectively decreased ROS and MMPs activity, and increased COL1A1 expression in both in vitro and in vivo models. This molecular-level repair translated to human-level benefits, as clinical trials showed improved hydration, elasticity, and decreased wrinkles. Key biomarkers analyzed included ROS, MMP-1, IL-6, TEWL, and COL1A1. Soy isoflavones protect the skin from premature aging by reducing oxidative stress, inhibiting collagen degradation, and stimulating collagen synthesis. This makes isoflavones a promising ingredient in natural antiaging therapies.