Intake of butter naturally enriched with cis9,trans11 conjugated linoleic acid reduces systemic inflammatory mediators in healthy young adults

A conjugated linoleic acid (CLA) depletion-repletion study was carried out to investigate the effects of dietary c9,t11 CLA on C-reactive protein, transcription factor NF kappa B, metalloproteinases 2 and 9, inflammatory mediators (adiponectin, TNF alpha, IL-2, IL-4, IL-8, IL-10), body composition, and erythrocyte membrane composition in healthy normal-weight human adults. CIA depletion was achieved through an 8-week period of restricted dairy fat intake (depletion phase; CIA intake was 5.2 +/- 5.8 mg/day), followed by an 8-week period in which individuals consumed 20 g/day of butter naturally enriched with c9,t11 CIA (repletion phase; CIA intake of 1020 +/- 167 mg/day). The participants were 29 healthy adult volunteers (19 women and 10 men, aged 22 to 36 years), with body mass index between 18.0 and 29.9 kg m(-2). Blood samples were collected at baseline and at the end of both depletion and repletion phases. The content of CLA in erythrocytes decreased during CIA-depletion and increased during CIA-repletion. Intake of CIA-enriched butter increased the serum levels of anti-inflammatory IL-10 but reduced transcription factor NF kappa B in blood and serum levels of TNF alpha, IL-2, IL-8 and inactive metalloproteinase-9. Moreover, reduced activity of metalloproteinases 2 and 9 in serum was observed during the CIA-repletion period. In contrast, intake of CIA-enriched butter had no effects on body composition (DXA analysis) as well as on serum levels of adiponectin, C-reactive protein, and IL-4. Taken together, our results indicate that the intake of a c9,t11 CLA-enriched butter by normal-weight subjects induces beneficial changes in immune modulators associated with sub-clinical inflammation in overweight individuals. (C) 2013 Elsevier Inc. All rights reserved.