Serum levels of trimethylamine N-oxide and kynurenine novel biomarkers are associated with adult metabolic syndrome and its components: a case-control study from the TEC cohort

Atieh Mirzababaei; Maryam Mahmoodi; Abbasali Keshtkar; Haleh Ashraf; Faezeh Abaj; Neda Soveid; Mahya Mehri Hajmir; Mina Radmehr; Pardis Khalili; Khadijeh Mirzaei

doi:10.3389/fnut.2024.1326782

Serum levels of trimethylamine N-oxide and kynurenine novel biomarkers are associated with adult metabolic syndrome and its components: a case-control study from the TEC cohort

Front Nutr. 2024 Jan 23:11:1326782. doi: 10.3389/fnut.2024.1326782. eCollection 2024.

Authors

Affiliations

¹ Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran.
² Department of Cellular and Molecular Nutrition, School of Nutritional Science and Dietetics, Tehran University of Medical Sciences, Tehran, Iran.
³ Department of Disaster and Emergency Health, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
⁴ Cardiac Primary Prevention Research Center, Cardiovascular Diseases Research Institute, Tehran University of Medical Sciences, Tehran, Iran.
⁵ Department of Nutrition, Dietetics and Food, School of Clinical Sciences at Monash Health, Monash University, Clayton, VIC, Australia.
⁶ Department of Nutrition, Science and Research Branch, Islamic Azad University, Tehran, Iran.

Abstract

Background: Epidemiologic research suggests that gut microbiota alteration (dysbiosis) may play a role in the pathogenesis of metabolic syndrome (MetS). Dysbiosis can influence Trimethylamine N-oxide (TMAO) a gut microbiota-derived metabolite, as well as kynurenine pathways (KP), which are known as a new marker for an early predictor of chronic diseases. Hence, the current study aimed to investigate the association between KYN and TMAO with MetS and its components.

Methods: This case-control study was conducted on 250 adults aged 18 years or over of Tehran University of Medical Sciences (TUMS) Employee's Cohort study (TEC) in the baseline phase. Data on the dietary intakes were collected using a validated dish-based food frequency questionnaire (FFQ) and dietary intakes of nitrite and nitrate were estimated using FFQ with 144 items. MetS was defined according to the NCEP ATP criteria. Serum profiles TMAO and KYN were measured by standard protocol.

Result: The mean level of TMAO and KYN in subjects with MetS was 51.49 pg/mL and 417.56 nmol/l. High levels of TMAO (≥30.39 pg/mL) with MetS were directly correlated, after adjusting for confounding factors, the odds of MetS in individuals 2.37 times increased (OR: 2.37, 95% CI: 1.31-4.28, P-value = 0.004), also, high levels of KYN (≥297.18 nmol/L) increased odds of Mets+ 1.48 times, which is statistically significant (OR: 1.48, 95% CI: 0.83-2.63, P-value = 0.04). High levels of TMAO compared with the reference group increased the odds of hypertriglyceridemia and low HDL in crude and adjusted models (P < 0.05). Additionally, there was a statistically significant high level of KYN increased odds of abdominal obesity (P < 0.05).

Conclusion: Our study revealed a positive association between serum TMAO and KYN levels and MetS and some of its components. For underlying mechanisms and possible clinical implications of the differences. Prospective studies in healthy individuals are necessary.

Keywords: dysbiosis 2; gut microbiota metabolites; kynurenine; metabolic syndrome; trimethylamine N-oxide.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This study was supported by the Tehran University of Medical Sciences (Grant No: 1401-2-212-58098).