Hsiao-Pei Tu1, Chan-Yen Kuo2, Martin Ming-Jen Fu3, Yu-Tang Chin4, Cheng-Yang Chiang3, Hsien-Chung Chiu3, Yi-Jan Hsia5, Earl Fu6. 1. Department of Oral Hygiene, Hsin-Sheng Junior College of Medical Care and Management, Taoyuan City, Taiwan. 2. Department of Research, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City, Taiwan. 3. School of Dentistry, National Defense Medical, Center and Tri-Service General Hospital, Taipei, Taiwan. 4. School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei, Taiwan; Center for Teeth Bank and Dental Stem Cell Technology, Taipei Medical University, Taipei, Taiwan. 5. School of Dentistry, National Defense Medical, Center and Tri-Service General Hospital, Taipei, Taiwan; Department of Dentistry, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City, Taiwan. 6. Department of Dentistry, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City, Taiwan. Electronic address: fuearl@gmail.com.
Abstract
OBJECTIVE: Cyanidin-3-O-glucoside (C3G), a dietary anthocyanin, possesses various biological properties, including alleviating endoplasmic reticulum (ER) stress. This study examined the effect of C3G on periodontitis via ER stress in rats. DESIGN: Periodontitis was induced by placing silk sutures around maxillary second molars. C3G (0, 3, or 9 mg/kg) was fed on the day before ligation (10 rats/group). Further, 10 non-ligation control rats received deionized water. On day 8, gingivae were obtained to determine CCAAT/enhancer-binding protein homologous protein (CHOP), c-Jun N-terminal kinase (JNK), phospho-JNK (p-JNK), and nuclear factor-κB (NF-κB) by immunoblotting. Periodontal destruction was evaluated using micro-computed tomography (μCT) and histology. RESULTS: Gingival expression of CHOP, p-JNK/JNK, and NF-κB significantly increased in ligation rats (0 mg/kg C3G) than that in controls. However, protein expression in ligation groups presented a negative association with C3G concentration. By μCT, the distance of cemento-enamel junction to bone significantly increased in ligation groups; however, distances showed a negative association with C3G concentration. In the region of interest, bone volume and trabecular thickness and number significantly decreased in ligation groups but they were positively associated with C3G concentration. In terms of trabecular separation, opposite results were found. Histologically, infiltrated connective tissue (ICT) and periodontal destructions increased in ligation groups; however, they were negatively associated with C3G concentration. Moreover, ICT area is positively correlated with μCT- and histologically measured destructions and protein expression of CHOP, p-JNK/JNK, or NF-κB. CONCLUSION: C3G promotes favorable modulation of ER stress and alleviates destruction of periodontitis, which may imply a new strategy.
OBJECTIVE: Cyanidin-3-O-glucoside (C3G), a dietary anthocyanin, possesses various biological properties, including alleviating endoplasmic reticulum (ER) stress. This study examined the effect of C3G on periodontitis via ER stress in rats. DESIGN: Periodontitis was induced by placing silk sutures around maxillary second molars. C3G (0, 3, or 9 mg/kg) was fed on the day before ligation (10 rats/group). Further, 10 non-ligation control rats received deionized water. On day 8, gingivae were obtained to determine CCAAT/enhancer-binding protein homologous protein (CHOP), c-Jun N-terminal kinase (JNK), phospho-JNK (p-JNK), and nuclear factor-κB (NF-κB) by immunoblotting. Periodontal destruction was evaluated using micro-computed tomography (μCT) and histology. RESULTS: Gingival expression of CHOP, p-JNK/JNK, and NF-κB significantly increased in ligation rats (0 mg/kg C3G) than that in controls. However, protein expression in ligation groups presented a negative association with C3G concentration. By μCT, the distance of cemento-enamel junction to bone significantly increased in ligation groups; however, distances showed a negative association with C3G concentration. In the region of interest, bone volume and trabecular thickness and number significantly decreased in ligation groups but they were positively associated with C3G concentration. In terms of trabecular separation, opposite results were found. Histologically, infiltrated connective tissue (ICT) and periodontal destructions increased in ligation groups; however, they were negatively associated with C3G concentration. Moreover, ICT area is positively correlated with μCT- and histologically measured destructions and protein expression of CHOP, p-JNK/JNK, or NF-κB. CONCLUSION: C3G promotes favorable modulation of ER stress and alleviates destruction of periodontitis, which may imply a new strategy.