Background: Growing evidence suggests that bioactive compounds in berry fruits may mitigate inflammation in patients with chronic kidney disease (CKD). 

Objectives: To evaluate cranberry (Vaccinium macrocarpon) supplementation effects on modulation of transcription factors involved in inflammation and oxidative stress in nondialysis (stages 3 and 4) patients with CKD. 

Design/Participants: A randomized, double-blind, placebo-controlled study was performed with 30 patients to receive capsules containing cranberry extract (1000 mg/day) or placebo (1000 mg/day of corn starch) for two months. 

Measurements: The mRNA expression of nuclear factor-erythroid 2-related factor-2 (Nrf2) and nuclear factor-kB (NF-kB) was evaluated in peripheral blood mononuclear cells (PBMCs) by quantitative real-time polymerase chain reaction. Thiobarbituric acid reactive substances (TBARS) were measured in the plasma to assess oxidative stress. Interleukin-6 (IL-6) plasma levels were assessed by enzyme-linked immunosorbent assay and C-reactive protein (CRP) by immunoturbidimetric method. 

Results: Twenty-five patients completed the study: 12 in the cranberry group (56.7 +/- 7.5 years and body mass index (BMI) of 29.6 +/- 5.5 kg/m(2)) and 13 in the placebo group (58.8 +/- 5.1 years and BMI 29.8 +/- 5.4 kg/m(2)). There were no differences in NF-kB or Nrf2 mRNA expressions ( p = 0.99 and p = 0.89 ) or TBARS, CRP, and IL-6 plasma levels after cranberry supplementation. 

Conclusions: The cranberry extract administration (1000 mg/day) did not affect Nrf2 and NF-kB mRNA expression, oxidative stress, or inflammatory markers levels in nondialysis CKD patients. This trial is registered with NCT04377919.