Effects of O‐methylated (−)‐epigallocatechin gallate (EGCG) on LPS‐induced osteoclastogenesis, bone resorption, and alveolar bone loss in mice

Abstract

(−)‐Epigallocatechin‐3‐ O ‐gallate ( EGCG ), present in green tea, exhibits antioxidant and antiallergy effects. EGCG 3″Me, a 3‐ O ‐methylated derivative of EGCG , has been reported to show similar biological functions; the inhibitory activity of EGCG 3″Me in a mouse allergy model was more potent than that of EGCG , probably due to the efficiency of absorption from the intestine. However, the functional potency of these EGCG s is controversial in each disease model. We previously observed that EGCG suppressed inflammatory bone resorption and prevented alveolar bone loss in a mouse model of periodontosis. In this study, we examined the role of EGCG 3″Me in bone resorption using a mouse model of periodontitis. Lipopolysaccharide ( LPS )‐induced osteoclast formation was suppressed by adding EGCG 3″Me to cocultures of osteoblasts and bone marrow cells, and LPS ‐induced bone resorption was also inhibited by EGCG 3″Me in calvarial organ cultures. EGCG 3″Me acted on osteoblasts and suppressed prostaglandin E ( PGE ) production, which is critical for inflammatory bone resorption, by inhibiting the expression of COX ‐2 and mPGES ‐1, key enzymes for PGE synthesis. In osteoclast precursor macrophages, EGCG 3″Me suppressed RANKL ‐dependent differentiation into mature osteoclasts. In a mouse model of periodontitis, LPS ‐induced bone resorption was suppressed by EGCG 3″Me in organ culture of mouse alveolar bone, and the alveolar bone loss was further attenuated by the treatment of EGCG 3″Me in the lower gingiva in vivo . EGCG 3″Me may be a potential natural compound for the protection of inflammatory bone loss in periodontitis.

Aminothiazoles inhibit osteoclastogenesis and PGE2 production in LPS‐stimulated co‐cultures of periodontal ligament and RAW 264.7 cells, and RANKL‐mediated osteoclastogenesis and bone resorption in PBMCs

“…Furthermore, in human PBMCs, these aminothiazoles, targeting mPGES‐1, reduced the LPS‐induced PGE 2 production as well as inhibited the RANKL‐stimulated osteoclastogenesis and bone resorption in the current study. Another study by Tominari et al showed that osteoclast differentiation from RANKL‐stimulated mouse bone marrow macrophages is suppressed by compounds inhibiting PGE 2 synthesis by targeting both COX‐2 and mPGES‐1. Both RANKL‐RANK and LPS‐TLR4 signalling pathways are mediated via transcription factor NF‐κB.…”

Sinomenine Regulates Inflammatory Response and Oxidative Stress via Nuclear Factor kappa B (NF-κB) and NF-E2-Related Factor 2 (Nrf2) Signaling Pathways in Ankle Fractures in Children

“…Our study shows that inflammatory factors in children with ankle fractures are significantly higher than those in healthy children. It has been reported that BK stimulates bone resorption in mice [ 22 ]. A previous study has reported that SIN reduces osteoclasts activity and bone resorption both in vivo and in vitro via inhibition of inflammation and immune responses [ 23 ].…”

The preventive and therapeutic application of garlic and other plant ingredients in the treatment of periodontal diseases (Review)

“…It has also been shown that ECG inhibits the biofilm formation of periodontal pathogens, such as P. gingivalis and Prevotella intermedia (11). It has been demonstrated that EGCG inhibits the resorption of alveolar bone induced by lipopolysaccharide (LPS) in mice suffering from periodontitis (12). In a preliminary clinical trial, the local application of green tea in the form of mouthwash or dentifrice was shown to produce an improved effect comparable to that of CHX on chronic periodontitis (13,14).…”