Twenty-four weeks of consuming 320 milligrams per day of anthocyanins were associated with reductions in inflammatory compounds like C-reactive protein (CRP) and soluble vascular cell adhesion molecule-1 (sVCAM-1) of 22% and 12%, respectively.
“This is the first report that long-term supplementation with purified anthocyanins can inhibit the inflammatory response in hypercholesterolemic subjects,” wrote researchers from Sun Yat-Sen University and Shaoguan University.
Results published in Nutrition, Metabolism and Cardiovascular Diseases also indicated that the anthocyanins had additive or synergistic effects, meaning that the sum of the effects was greater than the effects of the individual anthocyanins.
“Hence, incorporating plant-based foods rich in different anthocyanin compounds in the diet is likely to be more beneficial than consuming a single anthocyanin supplement,” they added.
Chronic inflammation is brought about by an over-expression or lack of control of the normal protective mechanisms.
In a review in Nutrition, Metabolism & Cardiovascular Diseases (2004, Vol. 14, pp. 228-232), Italian scientists noted that “obesity, insulin resistance, and diabetes are associated with a pro-inflammatory state, which in turn is associated with increased cardiovascular risk”.
Chronic inflammation has also been linked to a range of conditions linked to heart disease, osteoporosis, cognitive decline and Alzheimer's, type-2 diabetes, and arthritis.
Nutrients that exert an anti-inflammatory response are the subject of increasing interest from the interest, and from consumers, and some dietary supplements are already marketed by the ability to ‘balance’ the inflammatory response.
For the new study, the Chinese researchers recruited 150 people with high cholesterol levels to participate in their randomized, double-blind trial. Subjects were randomly assigned to receive either 320 milligrams per day of a purified anthocyanin mixture (Polyphenols AS, Norway) or placebo for 24 weeks.
Results showed that anthocyanin supplementation was associated with a 22% reduction in CRP levels, compared to only 2.5% in the placebo group. In addition, the anthocyanins were linked to a 12.3% reduction in sVCAM-1 levels, compared to 0.4% in the placebo group.
Levels of interleukin-1beta (IL-1beta) also decreased in the anthocyanin group by 12.8%, compared to only 1.3% in the placebo group.
Cholesterol improvements were also observed for participants of the anthocyanin group, with LDL levels falling by 10%, and HDL levels increasing by 14%, compared with an LDL increase of 0.3% and a decrease in HDL of 0.9% in the placebo group.
A cell study with individual anthocyanins revealed that the improvements in the inflammatory markers were greater for the anthocyanin mixture than for individual compounds.
“This suggests that the various anthocyanins in the mixture may synergistically operate to inhibit the inflammatory response,” wrote the researchers.
“Further, these in vitro findings support our observations in human subjects that anthocyanins can remarkably regulate the levels of inflammatory cytokines in hypercholesterolemic subjects.”
Source: Nutrition, Metabolism and Cardiovascular Diseases
Published online ahead of print, doi: 10.1016/j.numecd.2012.06.005
“Anti-inflammatory effect of purified dietary anthocyanin in adults with hypercholesterolemia: A randomized controlled trial”
Authors: Y. Zhu, W. Ling, H. Guo, F. Song, Q. Ye, T. Zou, D. Li, Y. Zhang, G. Li, Y. Xiao, F. Liu, Z. Li, Z. Shi, Y. Yang