Fig. 5: G3@SeHANs alleviate inflammatory bone loss in ligature-induced periodontitis.

a Schematic of mechanism by which cfDNA promotes bone loss; cfDNA-scavenging nanoparticles may prevent bone loss and alleviate periodontitis. b, c Experimental schedule of in vivo study. PAMAM-G3 (200 µg/mL), G3@SeHANs (1 mg/mL), or PBS (control group) were administered locally by injection with a microsyringe into gingival tissue at 5 µL per site at 6 sites around the ligature: the mesiobuccal gingiva, distobuccal gingiva, mesiopalatal gingiva, distopalatal gingiva, and mesial and distal gingival papilla. Microinjections were performed on days 0, 3, 6, 9, and 12. On experimental days without injections, materials or PBS were noninvasively smeared on the gingiva with disposable microapplicators. Both sides of the mice were treated with the same materials. Levels of (d) saliva cfDNA, (e) saliva TNF-α, (f) serum cfDNA, and (g) serum TNF-α at 15 days post-operation. Data are means ± SEM; n = 3 samples per group; *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001 by one-way ANOVA with Tukey’s multiple comparison test (d, P < 0.0001 between Normal and Untreated, P < 0.0001 between Untreated and G3@SeHANs, P < 0.0001 between PAMAM-G3 and G3@SeHANs; e P = 0.0006 between Normal and Untreated, P = 0.0124 between Untreated and G3@SeHANs; f P = 0.0023 between Normal and Untreated, P = 0.0004 between Untreated and G3@SeHANs, P = 0.0078 between PAMAM-G3 and G3@SeHANs; g P = 0.0009 between Normal and Untreated, P = 0.0035 between Untreated and G3@SeHANs). h, i Changes in cfDNA and TNF-α concentrations in the saliva of mice. Data are means ± SEM; n = 3 samples per group. j Bone loss measured by the vertical distance between the cementoenamel junction (CEJ) and alveolar bone crest (ABC) (CEJ-ABC) and the bone resorption area. Data are means ± SEM; n = 4 for normal group, n = 6 for untreated and PAMAM-G3 groups, n = 13 for G3@SeHANs group; *P < 0.05, **P < 0.01, ****P < 0.0001 by one-way ANOVA with Tukey’s multiple comparison test (Mesial, P < 0.0001 between Normal and Untreated, P = 0.0028 between Untreated and PAMAM-G3, P = 0.0026 between Untreated and G3@SeHANs; Distal, P < 0.0001 between Normal and Untreated, P = 0.0027 between Untreated and G3@SeHANs; Buccal, P < 0.0001 between Normal and Untreated, P = 0.0151 between Untreated and G3@SeHANs; Palatal, P < 0.0001 between Normal and Untreated, P = 0.0399 between Untreated and PAMAM-G3, P = 0.0339 between Untreated and G3@SeHANs). (k) Micro-CT scanning and 3D reconstruction of the bone loss.