Effect of orange juice and beverage with phytosterols on cytokines and PAI-1 activity

Abstract

Background & aims: Inflammation is pivotal in all phases of atherosclerosis. Dietary options which lower inflammatory biomarkers would be an attractive strategy to reduce risk from cardiovascular diseases and cancer. Indeed, fruit and vegetable intake or fruit juice consumption is associated with health and wellness. However, there is a paucity of data examining the effect of orange juice on biomarkers of inflammation in healthy volunteers. We have previously conducted the first placebo-controlled randomized studies examining the effect of sterol fortified orange juice or sterol fortified reduced calorie orange juice beverage supplementation (2 g sterols/day) compared to Placebo OJ or Placebo OJBev, and showed significant benefits on the lipid profile as well as significant reduction in hsCRP, the prototypic marker of inflammation and a cardiovascular risk marker. The aim of this study was to examine the effect of orange juice (OJ) or OJ beverage (Bev) alone and fortified with plant sterols (1g/240 ml juice or beverage twice a day) on pro-inflammatory cytokines and PAI-1, a marker of impaired fibrinolysis in healthy human volunteers.

Methods: In the first study, 72 healthy human volunteers received Placebo OJ or Sterol OJ and in the second study, 72 volunteers received OJBev or Sterol OJBev for 8 weeks and blood was drawn at baseline and following supplementation for 8 weeks. Biomarkers of Inflammation (IL-1b, IL-6, TNF, IL-8, IL-10) were assessed in serum using the BD Human Inflammatory Cytokine Cytometric Bead Array and PAI-1 activity was assessed in citrated plasma.

Results: OJ or OJBev alone failed to result in any significant effects on circulating cytokine levels or PAI-1 activity. There was a significant reduction in IL-1b with sterol fortified OJ (p < 0.05) compared to baseline. In addition, both sterol fortified OJ as well as sterol fortified OJBev resulted in significant reductions in serum IL-6 levels (p < 0.01).

Conclusion: Thus, sterol fortified OJ and OJ Beverage are able to effectively lower biomarkers of inflammation in healthy human volunteers in addition to providing lipid profile benefits and may thus contribute to decreasing cardiovascular risk.