Periodontitis is a common oral bacterial infection characterized by inflammatory responses. Its high prevalence lowers the quality of life for individuals and increases the global economic and disease burden. As microorganisms in dental plaque are responsible for this oral disease, antibacterial drug treatments are effective strategies for preventing and treating periodontitis. In this study, we investigated the inhibitory effect of nicotinamide (NAM), a vitamin B₃ derivative, on the growth and virulence of Porphyromonas gingivalis, a key member of the red complex. Our findings revealed that NAM inhibited bacterial growth and gingipain activities, which played a dominant role in protein hydrolysis and heme acquisition. NAM decreased hemagglutination and hemolysis abilities and changed hemin and hemoglobin binding capacities, controlling bacterial infection through a starvation strategy by blocking access to growth-essential nutrients from the outside and reducing bacterial virulence. Several experiments in an animal model showed the effectiveness of NAM in preventing alveolar bone loss and reducing inflammatory cell infiltration, shedding light on its potential therapeutic applicability.

中文翻译：

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烟酰胺通过抑制血红素摄取系统和牙龈蛋白酶活性，采用饥饿策略来对抗牙龈卟啉单胞菌毒力

牙周炎是一种常见的口腔细菌感染，以炎症反应为特征。其高患病率降低了个人的生活质量，并增加了全球经济和疾病负担。由于牙菌斑中的微生物是造成这种口腔疾病的原因，抗菌药物治疗是预防和治疗牙周炎的有效策略。_{在这项研究中，我们研究了烟酰胺 (NAM)（一种维生素 B 3衍生物）对}牙龈卟啉单胞菌（红色复合物的关键成员）的生长和毒力的抑制作用。我们的研究结果表明，NAM 抑制细菌生长和牙龈蛋白酶活性，这在蛋白质水解和血红素获取中起主导作用。NAM 降低了血凝和溶血能力，改变了血红素和血红蛋白的结合能力，通过阻断从外部获取生长必需营养物质并降低细菌毒力，通过饥饿策略控制细菌感染。多项动物模型实验表明，NAM 在预防牙槽骨流失和减少炎症细胞浸润方面具有有效性，揭示了其潜在的治疗适用性。