The potential heart health benefits of polyphenol-rich cocoa powder may be related to a ‘novel mechanism’ of boosting HDL (good) cholesterol, says a new study from Japan.
Researchers from the Food and Health R&D Laboratories at Japanese company Meiji Seika Kaisha report that cocoa’s potential ability to boost HDL levels is related to a proteins which boost levels of a compound called apolipoprotein A1 (Apo-A1), which is required by the body to produce HDL-cholesterol.
“As cholesterol metabolism is known to be regulated by several different mechanisms, it is possible that cacao polyphenols may act on multiple pathways as a regulatory receptor agonist or ligand, similar to other plant polyphenols,” wrote the researchers in the Journal of Agricultural and Food Chemistry.
The health benefits of polyphenols from cocoa have been gathering increasing column inches in the national media. To date studies have reported potential benefits for cardiovascular health, skin health, and even brain health.
The majority of science into the potential benefits of cocoa have revolved around cardiovascular benefits of the flavanols (also known as flavan-3-ols or catechins), and particularly the monomeric flavanol (-)epicatechin.
Recently, however, scientists from the University of Reading in England and Mars reported that cocoa may also affect gut microflora and possess prebiotic potential.
The new study takes us back to the health benefit with the strongest supporting science: Cardiovascular health. While it is known that consumption of cocoa polyphenols may boost HDL cholesterol levels, and decrease LDL cholesterol levels, the Japanese researchers state that “the mechanisms responsible for these effects of cocoa on cholesterol metabolism have yet to be fully elucidated”.
In an attempt to fill this knowledge gap, the Japanese researchers examined the effects of cacao polyphenols such as (−)-epicatechin, (+)-catechin, and procyanidin B2 and C1 in human intestinal cells.
Results showed that the polyphenols increased apo A1 protein levels, while levels of alipoprotein B, the main alipoprotein responsible for carrying LDL cholesterol to cells, decreased.
Digging deeper into the potential mechanism, the researchers add that the cocoa compounds were also associated with an increase in sterol regulatory element binding proteins (SREBPs).
“SREBP is primarily responsible for the regulation of genes involved in cholesterol biosynthesis and metabolism,” explained the researchers. “Therefore, these results suggest that cacao polyphenols participate in cholesterol metabolism.”
“These results elucidate a novel mechanism by which HDL cholesterol levels become elevated with daily cocoa intake,” they concluded.
Source: Journal of Agricultural and Food Chemistry
Published online ahead of print, doi: 10.1021/jf103820b
“Cacao Polyphenols Influence the Regulation of Apolipoprotein in HepG2 and Caco2 Cells.”
Authors: A. Yasuda, M. Natsume, N. Osakabe, K. Kawahata, J. Koga