Journal: Bioactive Materials

Article Title: Metformin alleviates aging-associated periodontitis via NRF2-mediated restoration of the IRE1α dependent unfolded protein response

doi: 10.1016/j.bioactmat.2026.03.060

Figure Lengend Snippet: Senescence-targeted, antibacterial, and hemostatic properties of composite hydrogels. (A) Fluorescence images of young and senescent PDLSCs (D-gal and LPS pretreated) incubated with Nile red (NR)-loaded Gal-MPDA for the indicated time periods. (B) Confocal fluorescence images showing the subcellular localization of GM@Nir in D-gal and LPS-induced senescent PDLSCs and cross-sectional analysis. Lysosome, Lyso tracker; Nuclei, Hoechst. (C) Live-dead staining for PDLSCs cells on day 1,3,5. (D) The viability of PDLSCs cells assessed by CCK-8 assay cocultured with composite hydrogels on day 1,3,5. (E) Representative optical images of the Hemolytic test after treating mouse blood with TA, TAM-GM, or TAM-GM@Met, followed by quantification analysis. (F) Live/dead staining of E. coli, S. aureus and P. gingivalis . ns, not significant. Data are presented as means ± SEM (n = 3 per subgroup). ∗∗∗P < 0.001.

Article Snippet: For fluorescence labeling, Nile red (HY-D0718, MCE) was added to 1 mg/mL MPDA nanoparticles and stirred at room temperature in the dark for 12 h. Then, galactan was added at a ratio of 1:2 with MPDA and stirred for another 12 h in the dark at room temperature.

Techniques: Fluorescence, Incubation, Staining, CCK-8 Assay

Journal: Bioactive Materials

Article Title: Metformin alleviates aging-associated periodontitis via NRF2-mediated restoration of the IRE1α dependent unfolded protein response

doi: 10.1016/j.bioactmat.2026.03.060

Figure Lengend Snippet: In vivo therapeutic effect of the TAM-GM@Met on mice with an aging-associated periodontitis model. (A) Schematic illustration of the therapeutic process on the D-gal induced aging mice periodontitis model. (B) Micro-CT reconstructions and buccal-palatal sectional views of maxillary molars and evaluation of the distance from the CEJ to the ABC. (C, D) Mice periodontal tissue sections prepared for H&E staining (C) and Masson's trichrome staining (D). (E) Schematic of TAM-GM@Met preparation. TAM hydrogel incorporates galactose-coated MPDA nanoparticles (GM) to target senescent cells for metformin delivery. Metformin activates NRF2, leading to transcriptional upregulation of IRE1α, restoration of the UPR, and suppression of SASP in PDLSCs. ns, not significant; TAM, tannic acid and Ag-MOFs based hydrogel; MPDA, mesoporous polydopamine; UPR, unfolded protein response. Data are presented as means ± SEM (n = 5 per subgroup). ∗∗∗P < 0.001.

Article Snippet: For fluorescence labeling, Nile red (HY-D0718, MCE) was added to 1 mg/mL MPDA nanoparticles and stirred at room temperature in the dark for 12 h. Then, galactan was added at a ratio of 1:2 with MPDA and stirred for another 12 h in the dark at room temperature.

Techniques: In Vivo, Micro-CT, Staining