What this means
BACKGROUND AND Mitochondrial dysfunction in macrophages drives pro-inflammatory M1 polarization in ulcerative colitis (UC). We developed a colon-targeted, mitochondria-directed nanoplatform (KSF@SS31@S100Ns) to restore mitochondrial fitness and alleviate UC.
A plain-English summary is on its way. Until then, this is the start of the authors' own summary.
- Who it was tested in
- Animals or cells
- Kind of research
- Research in animals or cells
The science
- Original title
- Oral Colon- and Mitochondria-Targeted Nanoparticles Alleviate Ulcerative Colitis by Reeducating Macrophage Polarization via SIRT3/FOXO3a-Mediated Mitochondrial Restoration.
- Authors
- Mei R, Zhang R, Li Z et al.
- Journal
- Journal of gastroenterology and hepatology
- Published
- Aug 25, 2026
- Study type
- Lab or animal study · indexed as animal research
- PMID
- 42638278 ↗
Abstract
Background
Mitochondrial dysfunction in macrophages drives pro-inflammatory M1 polarization in ulcerative colitis (UC). We developed a colon-targeted, mitochondria-directed nanoplatform (KSF@SS31@S100Ns) to restore mitochondrial fitness and alleviate UC.
What they did
Kaempferol-loaded silk fibroin (SF) nanoparticles were conjugated with SS-31 peptide and coated with pH-sensitive Eudragit S100. Physicochemical properties, release profile, and uptake were characterized. Mitochondrial function, macrophage polarization, and SIRT3/FOXO3a signaling were assessed in LPS-stimulated RAW264.7 cells. Efficacy and mechanisms were evaluated in a DSS-induced colitis mouse model.
What they found
Nanoparticles showed uniform size (~307 nm), high stability, and pH-dependent release. SS-31 enhanced macrophage uptake and mitochondrial localization. In vitro, KSF@SS31Ns restored mitochondrial membrane potential and ATP, reduced ROS, promoted mitophagy, and shifted macrophages toward the M2 phenotype via SIRT3/FOXO3a activation. In vivo, oral KSF@SS31@S100Ns accumulated in inflamed colons, reduced disease severity, suppressed pro-inflammatory cytokines, elevated IL-10, restored tight-junction proteins, and increased M2 macrophages. KSF@SS31@S100Ns effectively treats experimental colitis by restoring mitochondrial homeostasis, reprogramming macrophage polarization, and repairing the intestinal barrier, offering a translational nanotherapeutic strategy for UC.
The authors' abstract, grouped under plain headings from its own section labels.
Mei R, Zhang R, Li Z et al. Oral Colon- and Mitochondria-Targeted Nanoparticles Alleviate Ulcerative Colitis by Reeducating Macrophage Polarization via SIRT3/FOXO3a-Mediated Mitochondrial Restoration. Journal of gastroenterology and hepatology. 2026. doi:10.1111/jgh.70668. PMID: 42638278. https://pubmed.ncbi.nlm.nih.gov/42638278/
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