Journal: Bioactive Materials

Article Title: Glycosaminoglycan-functionalized hydrogels for sustained delivery of tissue inhibitor of metalloproteinase-3 mediating matrix metalloprotease inhibition and extracellular matrix stabilization

doi: 10.1016/j.bioactmat.2026.02.010

Figure Lengend Snippet: Biocompatibility of hydrogels. (A-C) Hydrogels were incubated in the respective cell culture media for 72 h, and the obtained extracts were used to assess their effects on the metabolic activity of huMECs (A), vSMCs (B), and NHDFs (C) after 48 h of culture. (D, E) Hydrogel extracts were added to primary human monocytes obtained from five independent donors. The differentiation efficiency of these immune cells into M1 (D) or M2 (E) macrophages was analyzed by flow cytometry using specific markers. (F) Anti-factor Xa activity of HA c and sHA c was determined in comparison with Hep using a chromogenic assay. (A-F) One-way ANOVA: ∗p < 0.05, ∗∗p < 0.01, ∗∗∗p < 0.001. (G) In-vivo assessment of GelMA and GelMA/sHA c hydrogels loaded with TIMP-3. Experimental overview: TIMP-3-loaded GelMA and GelMA/sHA c hydrogels were implanted subcutaneously into BALB/c mice for 14 days. (H) Representative histological images of explanted gels stained for MPO (neutrophils), CD68 (macrophages), CD31 (microvessels), and Sirius red (collagen deposition). The granulation tissue between the muscle tissue and the implant is highlighted by dotted yellow lines. (I-L) Quantification of MPO + and CD68 + cells, CD31 + events, and Sirius red intensity (three ROIs per sample). Statistical analysis was performed using an unpaired t -test with Welch's correction: ∗p < 0.05, ∗∗p < 0.01.

Article Snippet: Normal human dermal fibroblasts (NHDFs) (PromoCell GmbH, Heidelberg, Germany), were cultured in Dulbecco's modified eagle medium (DMEM) with 10 % fetal calf serum (FCS) and 1 % streptomycin and penicillin at 37 °C at 80 % confluency in 175 cm 2 flasks.

Techniques: Incubation, Cell Culture, Activity Assay, Flow Cytometry, Comparison, Chromogenic Assay, In Vivo, Staining

Journal: Bioactive Materials

Article Title: Glycosaminoglycan-functionalized hydrogels for sustained delivery of tissue inhibitor of metalloproteinase-3 mediating matrix metalloprotease inhibition and extracellular matrix stabilization

doi: 10.1016/j.bioactmat.2026.02.010

Figure Lengend Snippet: TIMP-3 maintains protease inhibitory activity in the presence of sHA c and hydrogels release bioactive TIMP-3. (A-D) Influence of soluble GAGs and hydrogel extracts on TIMP-3-mediated inhibition of protease activity in TNF-α-stimulated NHDFs. (A) Schematic of the experimental design. Inflammation was modeled by stimulating NHDFs with TNF-α, inducing increased protease secretion. Gelatinase/collagenase activity in supernatants was quantified using the EnzChek assay with a fluorogenic gelatin substrate in the presence or absence of soluble TIMP-3, soluble GAGs or hydrogel extracts. (B) Protease activity in the supernatants after TNF-α treatment relative to unstimulated controls. (C) Protease activity of TNF-α-stimulated supernatants incubated with soluble GAGs (HA c , sHA c ) with or without TIMP-3. (D) Protease activity of TNF-α-stimulated supernatants incubated with hydrogel extracts (prepared by 72 h hydrogel incubation in medium) in the absence or presence of TIMP-3. One-way ANOVA: ∗p < 0.05, ∗∗p < 0.01, ∗∗∗p < 0.001. Only significant differences relative to the Ctrl without TIMP-3 or relative to TIMP-3 alone are shown in C/D. (E) The inhibitory potential of TIMP-3 released from the hydrogels was measured using a MMP-9 activity assay. (F) The ratio of bioactive TIMP-3 to the total amount of released TIMP-3 was calculated and expressed as a fold change relative to GelMA hydrogels without GAGs. (G) Collagen-based ECMs were incubated with collagenase (CHC) for 20 or 60 min with TIMP-3 released from the hydrogels after 24 or 168 h. The remaining collagen was detected after Sirius red staining and elution. Two-way ANOVA for A, B: ∗p < 0.05, ∗∗p < 0.01, ∗∗∗p < 0.001. One-way ANOVA for C: ∗p < 0.05. (H) Molecular rationale for the regulatory role of sHA c on TIMP-3-mediated protease inhibition. The MD-refined complex of TIMP-3 (in grey) with HA6_3AC1 (atom-colored brown sticks, color gradient as in D) is shown superimposed with the TIMP-3/ADAM complex (PDB ID 3CKI ). ADAM is shown in green, and the corresponding TIMP-3 structure has been omitted for clarity.

Article Snippet: Normal human dermal fibroblasts (NHDFs) (PromoCell GmbH, Heidelberg, Germany), were cultured in Dulbecco's modified eagle medium (DMEM) with 10 % fetal calf serum (FCS) and 1 % streptomycin and penicillin at 37 °C at 80 % confluency in 175 cm 2 flasks.

Techniques: Activity Assay, Inhibition, Incubation, Staining