Lactation-stage profiles of rRNA-derived small RNAs in human milk exosome-enriched fractions: Compositional features and relevance to infant nutrition

作者：X Chen, Xiaoyu Liu, Ying Meng, Yutong Hu, Ze Guan, Xiqing Yue, Mei Yang · 发表于：Food Research International · 年份：2026 · DOI：10.1016/j.foodres.2026.119640 · 研究领域：Infant Nutrition and Health、Extracellular vesicles in disease、RNA Research and Splicing

Human milk exosome-enriched fractions contain exosome-like vesicles and bioactive molecules, yet the compositional features of rRNA-derived small RNAs (rsRNAs) and their variation across lactation stages remain unclear. In this study, exosome-enriched fractions were isolated and characterized from human colostrum (HC) and mature milk (HM) collected from healthy lactating mothers, and small RNA sequencing was used to systematically profile the rsRNA landscape, differential patterns, and positional origin distribution in these fractions. The results showed that human milk exosome-enriched fractions contained diverse rsRNAs, mainly derived from 18S, 28S, 5.8S, and 5S rRNAs. Compared with HM, rsRNAs in HC-derived exosome-enriched fractions exhibited marked differences in compositional proportion, length distribution, and abundance, indicating lactation-stage-associated variation. Coverage analysis further showed that most rsRNAs were not evenly distributed across full-length precursor rRNAs but were concentrated in specific regions, which is consistent with non-random enrichment patterns. Target prediction and functional enrichment analyses of representative differential rsRNAs suggested possible associations with pathways related to immune-related signaling, epithelial barrier function, and cell growth; however, these results should be interpreted as hypothesis-generating and require further experimental validation. Collectively, this study reveals the compositional characterist...