Blood plasma proteins reduce beneficial effects of dietary polyphenols

Scientists in China have discovered that blood plasma proteins reduce beneficial effects of dietary polyphenols in type II diabetes patients.

New research has found that raised glucose levels in the blood of diabetes patients have a significant effect on the structure of plasma proteins. This prevents proteins from carrying healthy antioxidants to cells and tissues. This reduces the effects of dietary polyphenols, which are commonly found in chocolate and red wine.

The team, led by Jianbo Xiao of Shanghai Normal University, found that type II diabetes plasma proteins have an affinity one to ten times lower for polyphenols than healthy proteins. Mr Xiao said: "The non-covalent interactions between polyphenols and plasma proteins are usually caused by four major forces: hydrogen bonding, van der Waals forces, hydrophobic interactions and electrostatic interactions."

Future research could extend these results to work with smaller molecules using methods such as fluorescence spectroscopy to analyse the interactions. The next step for Mr Xiao's team is to investigate why hydrophobic polyphenols cause a larger difference between the binding affinities of healthy and type II diabetes plasma proteins.