ABSTRACT
OBJECTIVE To investigate the effects and mechanism of atractylodin on inflammatory injury of periodontal tissue and alveolar bone loss in periodontitis rats. METHODS A total of 144 SD rats were divided into control group （intragastric and intraperitoneal injection of normal saline）， model group （intragastric and intraperitoneal injection of normal saline）， atractylodin low-dose， medium-dose and high-dose groups （intraperitoneal injection of 6.665， 13.33， and 26.66 mg/kg atractylodin）， metronidazole group （positive control group， intragastric injection of 0.05 g/kg metronidazole， intraperitoneal injection of normal saline）， AMD3100 [stromal cell-derived factor-1 （SDF-1）/CXC chemokine receptor-4 （CXCR4） pathway inhibitor] group （intragastric injection of 1 mg/kg AMD3100， intraperitoneal injection of normal saline）， atractylodin high-dose+AMD 3100 group （intraperitoneal injection of 26.66 mg/kg atractylodin， intragastric injection of 1 mg/kg AMD3100）， with 18 rats in each group. Except for the control group， all other groups of rats were inoculated with Porphyromonas gingivalis to construct a periodontitis model. After successful modeling， they were given relevant medicine or normal saline， once a day， for 4 consecutive weeks. The gingival index of rats was detected； the levels of interleukin-6 （IL-6） and tumor necrosis factor α （TNF-α） in rat serum were also determined； alveolar bone resorption， periodontal histopathologic changes and the number of osteoclasts were detected by methylene blue staining， HE staining and TRAP staining， respectively. The expressions of osteoprotegerin （OPG）， receptor activator of NF-κB ligand （RANKL）， SDF-1 and CXCR4 proteins were determined. RESULTS Compared with the control group， serious pathological injury of periodontal tissue was found in the model group， the gingival index， the levels of IL-6 and TNF- α， alveolar bone absorption value， the number of osteoclasts， and the expression of RANKL protein were all increased significantly （P＜0.05）， while the expressions of OPG， SDF-1 and CXCR4 proteins were decreased significantly （P＜0.05）. Compared with the model group， pathological injury of periodontal tissue in rats was reduced； the gingival index， the levels of IL-6 and TNF-α， alveolar bone resorption value， osteoclast number and RANKL protein expression were decreased significantly， while protein expressions of OPG， SDF-1 and CXCR4 were increased significantly in atractylodin low-dose， medium-dose and high-dose groups and metronidazole group （P＜0.05）. The change trend of corresponding indexes in the AMD3100 group was opposite to the above （P＜0.05）. AMD3100 attenuated the inhibitory effect of high-dose atractylodin on inflammatory response and alveolar bone loss in rats with periodontitis （P＜0.05）. CONCLUSIONS Atractylodin may improve the inflammatory response and alveolar bone loss in periodontitis rats by activating the SDF-1/CXCR4 signaling pathway.