Gelatin Methacryloyl Hydrogel Encapsulating CiMECs-Derived Extracellular Vesicles Ameliorates Lactation Function via Alleviating Mammary Oxidative Stress [miRNA-Seq]

Methods

We constructed an injectable gelatin methacryloyl (GelMA) hydrogel system to encapsulate chemically induced mammary epithelial cell-derived EVs (CiMECs-EVs), and systematically evaluated their antioxidant and lactogenic activities via multi-omics analysis, cellular functional assays and a bromocriptine-induced murine hypogalactia model. Results: CiMECs- EVs induced a functional mammary epithelial-like phenotype in fibroblasts in a dose-dependent manner, with functional cargo enriched in glutathione metabolism and redox-regulatory miRNAs.

The GelMA matrix protected EV integrity and enabled sustained release, and the composite system significantly ameliorated mammary duct structure and lactation function in vivo with specific mammary tropism and no systemic toxicity, outperforming free EV treatment. Conclusions: This study presents a safe protein biomacromolecule-based antioxidant delivery platform that effectively restores mammary redox balance and antioxidant defenses, providing a promising non-hormonal therapeutic strategy for postpartum hypogalactia.