Tobacco induces abnormal metabolism of tryptophan via the kynurenine pathway

Objectives: This study aims to investigate the effect of smoking on the metabolism of kynurenine and thus contribute to the elucidation of the potential mechanism of cigarette smoking. Methods: The study included 82 smokers and 63 nonsmokers who applied to the Family Medicine Polyclinic for routine check-ups. Sociodemographic data, routine laboratory results, Framingham risk scores (FRS), and Fagerström Nicotine Dependence Test (FTND) were recorded. Serum tryptophan, kynurenine, kynurenic acid, 3-hydroxyanthranilic acid, 3-hydroxykynurenine, and quinolinic acid concentrations were measured with tandem mass spectrometry. Results: Serum tryptophan levels (p=0.040) were statistically significantly lower in smokers, and the kynurenine/tryptophan ratio and serum kynurenine, kynurenic acid, quinolinic acid, 3-hydroxyanthranilic acid levels were higher (p<0.001). The correlation analysis in the smoker group showed a positive correlation between serum kynurenic acid levels and FTDN. The serum kynurenine levels were positively correlated with the levels of total cholesterol, triglyceride, low-density lipoprotein cholesterol, and FRS. There was a positive correlation between serum quinolinic acid levels and participants’ systolic and diastolic blood pressures. Conclusions: Our findings showed that tryptophan metabolism via the kynurenine pathway was induced in smokers.

Object Details

• Location: Deutsche Nationalbibliothek Frankfurt am Main
• Extent: Online-Ressource
• Language: Englisch

References and Relationships

• Bibliographic citation: Tobacco induces abnormal metabolism of tryptophan via the kynurenine pathway ; volume:50 ; number:1 ; year:2025 ; pages:152-159 ; extent:08 ; Turkish journal of biochemistry ; 50, Heft 1 (2025), 152-159 (gesamt 08)

Contributors, Places and Time

• Creator: Onmaz, Mustafa ; Eryavuz Onmaz, Duygu ; Demirbas, Nur ; Kutlu, Ruhusen ; Unlu, Ali ; Hatir, Ahmet Emre

Further information

• DOI: 10.1515/tjb-2024-0286
• URN: urn:nbn:de:101:1-2502280604507.707002873343
• Rights: Open Access; Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Last update: 15.08.2025, 7:28 AM CEST