EGCG and Baicalin Inhibit M1 Polarization of Macrophages in Mice Periodontitis through mTOR Synergistically

doi:10.13701/j.cnki.kqyxyj.2021.07.010

Abstract

Abstract: Objective: To explore whether Epigallocatechin Gallate (EGCG) and baicalin have synergistic effects in the treatment of mice periodontitis and potential mechanisms. Methods: C57/BL6 mice were randomly divided into blank control group, periodontitis group, EGCG group, EGCG+ baicalin group. The changes of periodontal histology and alveolar bone absorption were observed by HE staining. TRAP staining was used to observe the number of osteoclasts. Immunohistochemistry was used to observe the number of macrophages in all subtypes and the expression of mTOR. Results: Experimental periodontitis was successfully induced by ligation of silk thread combined with local inoculation of Porphyromonas gingivalis. The use of EGCG alone or baicalin in combination reduced periodontal inflammation and alveolar bone absorption, reduce the number of osteoclasts, M1 macrophages, and the ratio of M1 and M2, inhibited the expression of mTOR in periodontal tissues, and the combined use of EGCG and baicalin was more effective than the use of EGCG alone. Conclusion: EGCG and baicalin can synergistically treat periodontitis, which may be related to the down-regulation of mTOR signaling pathway and the reduction of macrophage polarization toward M1.

Key words: epigallocatechin gallate, baicalin, periodontitis, macrophage, mTOR

ZHOU Yi, CHEN Zhen, LIU Yangruoxuan, HU Liqun, YUAN Minyan, YAN Lu, HUANG Shengfu, LI Yuhong. EGCG and Baicalin Inhibit M1 Polarization of Macrophages in Mice Periodontitis through mTOR Synergistically[J]. Journal of Oral Science Research, 2021, 37(7): 622-627.

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