Brazilian propolis mitigates impaired glucose and lipid metabolism in experimental periodontitis in mice. Issue 1 (December 2016)

• Record Type: Journal Article
• Authors: Nakajima, Mayuka; Arimatsu, Kei; Minagawa, Takayoshi; Matsuda, Yumi; Sato, Keisuke; Takahashi, Naoki; Nakajima, Takako; Yamazaki, Kazuhisa
• Is Part Of: BMC complementary and alternative medicine. Volume 16:Issue 1(2016)
• Page Start: 1
• Page End: 9
• Publication Date: 2016-12
• Subjects: Periodontitis -- Propolis -- Porphyromonas gingivalis -- Liver -- Adipose tissue -- Endotoxemia; Alternative medicine -- Periodicals; Complementary Therapies -- Periodicals; 615.505
• DOI: 10.1186/s12906-016-1305-8
• Languages: English
• ISSNs: 1472-6882

Abstract

Abstract Background Periodontitis has been implicated as a risk factor for metabolic disorders associated with insulin resistance. Recently, we have demonstrated that orally administeredPorphyromonas gingivalis, a representative periodontopathic bacterium, induces endotoxemia via reduced gut barrier function coupled with changes in gut microbiota composition, resulting in systemic inflammation and insulin resistance. Propolis, a resinous substance collected by honeybees from leaf buds and cracks in the bark of various plants, can positively affect metabolic disorders in various experimental models. In this study, we thus aimed to clarify the effect of propolis on impaired glucose and lipid metabolism induced byP. gingivalis administration. Methods Eight-week-old male C57BL/6 mice were orally administeredP. gingivalis strain W83, propolis ethanol extract powder withP. gingivalis, or vehicle. We then analyzed the expression profile of glucose and lipid metabolism-related genes in the liver and adipose tissues. Serum endotoxin levels were also evaluated by a limulus amebocyte lysate test. In addition, we performed histological analysis of the liver and quantified alveolar bone loss by measuring the root surface area on the lower first molar. Results Oral administration ofP. gingivalis induced downregulation of genes that improve insulin sensitivity in adipose tissue (C1qtnf9, Irs1, andSirt1 ), but upregulation of genes associated with lipid droplet formation and gluconeogenesis (Plin2, Acox, andG6pc ). However, concomitant administration of propolis abrogated these adverse effects ofP. gingivalis . Consistent with gene expression, histological analysis showed that administered propolis suppressed hepatic steatosis induced byP. gingivalis . Furthermore, propolis inhibited the elevation of serum endotoxin levels induced byP. gingivalis administration. Contrary to the systemic effects, propolis had no beneficial effect on alveolar bone loss. Conclusion These results suggest that administration of propolis may be effective in suppressing periodontopathic bacteria-induced metabolic changes that increase the risk of various systemic diseases.