A peptide derived from rice inhibits alveolar bone resorption via suppression of inflammatory cytokine production

Abstract

Background Periodontitis is an inflammatory disease that results in alveolar bone resorption due to inflammatory cytokine production induced by bacterial antigens such as lipopolysaccharides (LPS). Here, the preventive effect of the Amyl‐1‐18 peptide derived from rice in an experimental model of periodontitis and the effect on the anti‐inflammatory response were assessed. Methods Alveolar bone resorption, gene transcription of proinflammatory cytokines in the gingiva, and the endotoxin level in the oral cavity were evaluated after oral administration of the Amyl‐1‐18 peptide for 14 days using a ligature‐induced periodontitis model in mice. Additionally, murine macrophages were incubated with LPS of Escherichia coli or Porphyromonas gingivalis in the presence of Amyl‐1‐18 to analyze the suppressive effects of Amyl‐1‐18 on the cell signaling pathways associated with proinflammatory cytokine production, including inflammasome activities. Results Oral administration of Amyl‐1‐18 suppressed alveolar bone resorption and gene transcription of interleukin (il)6 in the gingiva of the periodontitis model, and decreased endotoxin levels in the oral cavity, suggesting modulation of periodontal inflammation by inhibition of endotoxin activities in vivo. Also, Amyl‐1‐18 suppressed IL‐6 production induced by LPS and recombinant IL‐1β in macrophages in vitro but had no effect on inflammasome activity. Conclusions The Amyl‐1‐18 peptide from rice inhibited alveolar bone destruction in mouse periodontitis model via suppressing inflammatory cytokine production induced by LPS. It was suggested that Amyl‐1‐18 peptide has anti‐inflammatory property against LPS, not only by neutralization of LPS and subsequent inhibition of nuclear factor‐κB signaling but also by inhibition of the IL‐1R‐related signaling cascade.

Application of Ligature-Induced Periodontitis in Mice to Explore the Molecular Mechanism of Periodontal Disease

“…Another peptide from rice, Amyl-1-18, also significantly prevented alveolar bone destruction in mice with ligature-induced periodontitis via suppression of LPS-induced inflammatory cytokine production. These results suggested that the Amyl-1-18 peptide has anti-inflammatory properties against LPS [218].…”

“…Food-derived peptides have been reported to have a wide range of activities, including antibacterial effects, blood-pressure-lowering effects, antioxidant activities, and cytoprotective or immunomodulatory effects [215,216]; however, little is known about their effects on inflammation and bone resorption in periodontitis. Several researchers have investigated the effects of bioactive peptides derived from foods on periodontitis [217,218]. Local treatment with rice endosperm protein (REP) 9 and 11 significantly inhibited the activity of inflammatory and osteoclast-related molecules and significantly decreased bone resorption in a ligature-induced periodontitis mouse model [217].…”

Semaphorin 3A protects against alveolar bone loss during orthodontic tooth movement in mice with periodontitis

“…In experiments in germ‐free animals, the placement of ligatures did not induce significant gingival inflammation or bone loss, 35 which indicates that bacteria are involved in periodontal tissue destruction in ligature models. In addition, it has been reported that bacterial growth and increasing LPS in periodontal tissues in ligature models correlate with increased proinflammatory cytokine production and bone loss, and blocking LPS signaling inhibits bone loss 36,37 . Previous studies have shown that LPS may be involved in gingival inflammation and bone loss in the ligation model 38 .…”

“…In addition, it has been reported that bacterial growth and increasing LPS in periodontal tissues in ligature models correlate with increased proinflammatory cytokine production and bone loss, and blocking LPS signaling inhibits bone loss. 36,37 Previous studies have shown that LPS may be involved in gingival inflammation and bone loss in the ligation model. 38 PDL is one of the tissues that responds to mechanical stimulation caused by orthodontic force.…”

Effect of environmental tobacco smoke on COX‐2 and SHP‐2 expression in a periodontitis rat model

“…Inflammation in the periodontal tissue and bone loss are the main characteristics of periodontitis (Offenbacher, 1996). Periodontal diseases are mediated by the host inflammatory response against bacteria in the periodontal tissue during the process of bone loss (Aoki‐Nonaka et al., 2019). Complex inflammatory signals and molecules, including MMP, RANKL, IL‐1β, IL‐6, TNF‐α, and PGE2, regulate osteoclastogenesis (Araújo et al., 2013).…”