Human umbilical cord mesenchymal stem cell-derived exosomes alleviate experimental colitis by maintaining the intestinal barrier and remodeling macrophage polarization

Figure 2 Human umbilical cord mesenchymal stem cell-derived exosomes attenuate dextran sulfate sodium-induced colitis in mice. A: Daily body weight changes in each group (dextran sulfate sodium vs human umbilical cord mesenchymal stem cell-derived exosomes); B: Disease activity index (DAI) scores in each group; C: Gross appearance of representative colons from mice in each group; D: Colon lengths of mice in each group; E: Macroscopic appearance of spleens from mice in each group; F: Spleen index of mice in each group; G: Representative histopathological changes in colon tissues assessed by hematoxylin and eosin staining (20 ×, scale bar = 200 μm; 40 ×, scale bar = 100 μm); H: Histological score of colons in each group; I: Colonic myeloperoxidase activity in each group; J-M: Messenger RNA expression levels of the inflammatory cytokines IL-12, IL-18, TGF-β, and IL-4. Data are presented as the mean ± SD. ^aP < 0.05. ^bP < 0.01. ^cP < 0.001. ^dP < 0.0001. Each experiment was repeated three times independently (n = 8 mice per group). NC: Negative control; DSS: Dextran sulfate sodium; MPO: Myeloperoxidase; IL: Interleukin; mRNA: Messenger RNA; TGF: Transforming growth factor; hucMSC-Ex: Human umbilical cord mesenchymal stem cell-derived exosomes.