Department of Pediatric Dentistry, College of Dentistry, University of Illinois at Chicago, IL, USA; Institute of Stomatological Research, Guanghua School of Stomatology, Sun Yat-sen University, 74 Zhong Shan Er Road, Guangzhou, China.
Arch Oral Biol. 2013 Nov;58(11):1686-91. doi: 10.1016/j.archoralbio.2013.08.014. Epub 2013 Sep 6.
Halitosis is a common complaint affecting the majority of the population. Mouthrinses containing cetylpyridinium chloride (CPC) have been used as oral hygiene aids to suppress oral malodor. Although the clinical efficacy of these mouthrinses has been well-documented, the mechanism whereby CPC reduces malodor is less-well-understood. We hypothesized that CPC suppresses expression of the genes (mgl and cdl) and enzymes responsible for methyl mercaptan (CH3SH) and hydrogen sulfide (H2S) production by oral anaerobes associated with halitosis. In this study, the mgl and cdl expression of Porphyromonas gingivalis and Fusobacterium nucleatum in the presence of CPC was investigated.
We used a microdilution method to determine the growth and production of volatile sulfur compounds (VSCs) by P. gingivalis W83 and F. nucleatum ATCC 10953 in respective media containing CPC (0.5 μg/mL to 1.5 μg/mL). For metabolic activity, we used an XTT {2,3-bis(2-methyloxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide} reduction assay. We used real-time RT-PCR and Western blotting to evaluate the effect of CPC at sub-MIC levels on mgl and cdl expression at the transcriptional and enzymatic levels.
CPC inhibited the growth of P. gingivalis and F. nucleatum at MICs of 3 μg/mL and 2 μg/mL, and at MBCs of 6 μg/mL and 3 μg/mL, respectively. Compared with untreated controls, CPC at 1.5 μg/mL suppressed CH3SH production of P. gingivalis by 69.84%±2.88% and H2S production of F. nucleatum by 82.55%±8.36% (p<0.05) without affecting metabolic activity. Inhibition of mgl mRNA (81.58%±20.33%) and protein (39.15%±6.65%) expression in P. gingivalis and inhibition of cdl mRNA (61.76%±13.75%) and protein (64.34%±1.62%) expression in F. nucleatum were also noted (p<0.05).
CPC represents an effective agent for halitosis reduction by inhibiting the growth and suppressing the expression of specific genes related to VSC production in anaerobic periodontal pathogens.
口臭是一种常见的问题，影响着大多数人群。含有氯化十六烷基吡啶（CPC）的漱口液已被用作口腔卫生助剂来抑制口腔异味。尽管这些漱口液的临床疗效已经得到充分证实，但 CPC 减少异味的机制还不太清楚。我们假设 CPC 抑制与口臭相关的口腔厌氧菌产生甲基硫醇（CH3SH）和硫化氢（H2S）的基因（mgl 和 cdl）和酶的表达。在这项研究中，我们研究了 CPC 存在时牙龈卟啉单胞菌和核梭杆菌的 mgl 和 cdl 表达。
我们使用微量稀释法来确定 CPC（0.5μg/mL 至 1.5μg/mL）存在的情况下，牙龈卟啉单胞菌 W83 和核梭杆菌 ATCC 10953 在各自培养基中的挥发性硫化合物（VSCs）的生长和产生。对于代谢活性，我们使用 XTT（2,3-双（2-甲氧基-4-硝基-5-磺苯基）-2H-四唑-5-羧基苯胺）还原测定法。我们使用实时 RT-PCR 和 Western blot 来评估亚 MIC 水平的 CPC 对 mgl 和 cdl 表达在转录和酶水平上的影响。
CPC 在 MIC 为 3μg/mL 和 2μg/mL 时抑制牙龈卟啉单胞菌和核梭杆菌的生长，在 MBC 分别为 6μg/mL 和 3μg/mL 时抑制生长。与未处理的对照组相比，1.5μg/mL 的 CPC 抑制了牙龈卟啉单胞菌 CH3SH 的产生，抑制率为 69.84%±2.88%，核梭杆菌 H2S 的产生，抑制率为 82.55%±8.36%（p<0.05），而不影响代谢活性。牙龈卟啉单胞菌的 mgl mRNA（81.58%±20.33%）和蛋白（39.15%±6.65%）表达以及核梭杆菌的 cdl mRNA（61.76%±13.75%）和蛋白（64.34%±1.62%）表达均受到抑制（p<0.05）。
CPC 通过抑制与厌氧牙周病原体中 VSC 产生相关的特定基因的生长和表达，代表了一种减少口臭的有效制剂。
