Novel Short Peptides Enhance the Intestinal Barrier to Promote Nutrient Absorption via the JAK-STAT Pathway Based on Transcriptomics and AlphaFold3

Short peptides are emerging as promising bioactive agents for improving gut health, but their mechanistic roles remain incompletely understood. In this study, novel short peptides derived from enzymatically hydrolyzed chicken proteins were investigated for their ability to enhance the intestinal barrier and subsequently promote nutrient absorption. Circular dichroism spectroscopy revealed stable secondary structures including α-helices and β-sheets, while <i>in vitro</i> digestion assays confirmed high gastrointestinal stability. <i>In vivo</i> studies showed that peptide administration maintained body weight and had no hepatotoxic effects. Immunofluorescence and RT-PCR analysis demonstrated increased expression of tight junction protein ZO-1 and Occludin gene, indicating reinforced epithelial barrier function. This enhanced barrier integrity was associated with the upregulation of nutrient absorption-related genes such as Mme and Cyp3a11, as revealed by transcriptomic analysis. Furthermore, activation of the JAK-STAT signaling pathway suggested a key role in mediating these effects. Molecular simulations via AlphaFold3 showed strong binding affinities of peptides GPEGPPGFP and VPPPFNP to their respective targets MME and CYP3A11. Collectively, these findings support a mechanistic model wherein short peptides improved the intestinal barrier, which in turn facilitates promoted nutrient uptake─highlighting their potential application in functional foods targeting gut health.