RAS inhibition modulates kynurenine levels in a CKD population with and without type 2 diabetes mellitus

Kynurenine pathway of tryptophan metabolism is involved in the pathophysiology of chronic kidney disease (CKD) and diabetes mellitus, mainly through the inflammation-induced activity of indoleamine 2,3-dioxygenase (IDO), and few studies have investigated its potential link with proteinuria. Renin-angiotensin system inhibitors (RASis) are recommended in these patients to decrease proteinuria, slow CKD progression and reduce cardiovascular risk, but whether these drugs influence kynurenine levels in humans is unknown. We evaluated serum tryptophan and kynurenine in patients suffering from CKD with or without type 2 diabetes mellitus, their correlations with markers of reduced kidney function, and their relationship with RAS-inhibiting therapy. Of 72 adult patients enrolled, 55 were receiving RASis, whereas 17 were not. Tryptophan was assessed by HPLC (high-performance liquid chromatography); kynurenine was measured using an enzyme-linked immunosorbent assay kit; IDO activity (%) was calculated with the formula (kynurenine/tryptophan) × 100. Kynurenine levels were significantly lower in the group under RASis compared to the untreated group (1.56 ± 0.79 vs 2.16 ± 1.51 µmol/l; P = 0.0378). In patients not receiving RASis, kynurenine was inversely related to estimated glomerular filtration rate (eGFR) (r = - 0.4862; P = 0.0478) and directly related to both proteinuria (ρ = 0.493; P = 0.0444) and albuminuria (ρ = 0.542; P = 0.0247). IDO activity was higher in patients with history of cardiovascular disease compared to patients with no such history, and it negatively correlated with eGFR (ρ = - 0.554; P = 0.0210) in the same group. These findings may contribute to explain the well-known beneficial effects of RAS inhibition in CKD population, especially considering that kynurenine is emerging as a potential new biomarker of CKD.

Medienart:

E-Artikel

Erscheinungsjahr:

2020

Erschienen:

2020

Enthalten in:

Zur Gesamtaufnahme - volume:52

Enthalten in:

International urology and nephrology - 52(2020), 6 vom: 20. Juni, Seite 1125-1133

Sprache:

Englisch

Beteiligte Personen:

Cernaro, Valeria [VerfasserIn]
Loddo, Saverio [VerfasserIn]
Macaione, Vincenzo [VerfasserIn]
Ferlazzo, Valentina Teresa [VerfasserIn]
Cigala, Rosalia Maria [VerfasserIn]
Crea, Francesco [VerfasserIn]
De Stefano, Concetta [VerfasserIn]
Genovese, Antonina Rita Rosalia [VerfasserIn]
Gembillo, Guido [VerfasserIn]
Bolignano, Davide [VerfasserIn]
Santoro, Domenico [VerfasserIn]
Vita, Roberto [VerfasserIn]
Buemi, Michele [VerfasserIn]
Benvenga, Salvatore [VerfasserIn]

Links:

Volltext

Themen:

343-65-7
8DUH1N11BX
Albuminuria
Angiotensins
EC 3.4.23.15
IDO activity
Journal Article
Kynurenine
Observational Study
Proteinuria
Renin
Renin–angiotensin system inhibitors (RASis)
Tryptophan

Anmerkungen:

Date Completed 26.02.2021

Date Revised 26.02.2021

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1007/s11255-020-02469-z

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM308986342