Department of Periodontology, Faculty of Dentistry, Ankara University, Ankara, Turkey.
Department of Periodontology, Faculty of Dentistry, Medipol University, İstanbul, Turkey.
J Periodontal Res. 2023 Oct;58(5):1041-1051. doi: 10.1111/jre.13166. Epub 2023 Aug 1.
The aim of this study was to identify the effects of smoking and periodontal inflammation on tryptophan-kynurenine metabolism as well as the correlation between these findings and clinical periodontal parameters.
It has been shown that the tryptophan amino acid's primary catabolic pathway, the kynurenine pathway (KP), may serve as a key biomarker for periodontal disease. Although there are studies investigating the effect of smoking on KYN-TRP metabolism, the effect of smoking on periodontal disease through KP has not been revealed so far.
The salivary and serum samples were gathered from 24 nonsmoker (NS-P) stage III, grade B generalized periodontitis and 22 smoker (S-P) stage III, grade C generalized periodontitis patients, in addition to 24 nonsmoker (NS-C) and 24 smoker (S-C) periodontally healthy control individuals. Saliva and serum IL-6, kynurenine (KYN), and tryptophan (TRP) values, and KYN/TRP ratio were analyzed by liquid chromatography-mass spectrometry. Clinical periodontal measurements were recorded.
Salivary TRP values were significantly higher in both periodontitis groups than control groups (p < .05). Salivary KYN values were highest in NS-P group (p < .05). Salivary KYN values did not differ significantly between periodontitis groups (p = .84). Salivary KYN/TRP ratio was significantly lower in NS-P group compared to other groups (p < .001). Serum TRP value is higher in S-P group than other groups; however, significant difference was found in S-C group (p < .05). Serum KYN values were significantly lower in smokers than nonsmokers. Serum KYN/TRP ratio is higher in NS-P group. NS-P group has the highest salivary IL-6 levels, NS-C group has the lowest values (p < .05).
Our results point out that smoking exacerbates inflammation in the periodontium and increases TRP destruction and decreases IDO activity by suppressing KP in serum. As a result, kynurenine and its metabolites may be significant biomarkers in the link between smoking and periodontal disease.
本研究旨在确定吸烟和牙周炎对色氨酸-犬尿氨酸代谢的影响，以及这些发现与临床牙周参数之间的相关性。
已表明，色氨酸氨基酸的主要分解代谢途径，犬尿氨酸途径（KP），可能作为牙周病的关键生物标志物。尽管有研究调查吸烟对 KYN-TRP 代谢的影响，但迄今为止，吸烟对 KP 下牙周病的影响尚未揭示。
采集了 24 名非吸烟者（NS-P）III 期 B 级广泛性牙周炎和 22 名吸烟者（S-P）III 期 C 级广泛性牙周炎患者、24 名非吸烟者（NS-C）和 24 名吸烟者（S-C）牙周健康对照者的唾液和血清样本。通过液相色谱-质谱法分析唾液和血清中 IL-6、犬尿氨酸（KYN）和色氨酸（TRP）值以及 KYN/TRP 比值。记录临床牙周测量值。
两组牙周炎患者的唾液 TRP 值均明显高于对照组（p<.05）。NS-P 组唾液 KYN 值最高（p<.05）。牙周炎组之间的唾液 KYN 值无显著差异（p=.84）。NS-P 组唾液 KYN/TRP 比值明显低于其他组（p<.001）。S-P 组血清 TRP 值高于其他组，但 S-C 组差异有统计学意义（p<.05）。吸烟者血清 KYN 值低于非吸烟者。血清 KYN/TRP 比值在 NS-P 组较高。NS-P 组唾液 IL-6 水平最高，NS-C 组最低（p<.05）。
我们的研究结果表明，吸烟通过抑制血清中的 KP，加重牙周组织炎症，增加 TRP 破坏，降低 IDO 活性。因此，犬尿氨酸及其代谢物可能是吸烟与牙周病之间关联的重要生物标志物。
