Tea polyphenols show antiglycation promise for diabetics
Polyphenols such as the catechin EGCG are understood to make up around 30 per cent of the dry leaf weight for green team; EGCG is thought to be one of the most beneficial catechins. Recent research on its benefits has looked as such diverse indications as arthritis, mental distress, oral health and weight loss.
A body of research has already investigated a possible link between green tea consumption and diabetes risk, and tea-drinking may bring modest benefits for glucose homeostasis and help keep the cardiovascular system healthy.
For a new study in the journal Food Chemistry, researchers from Taiwan set out to determine the anti-oxidant and antiglycation effects of EGCG under high glucose conditions that diabetes.
To mimic the in vivo situation, the human plasma was preincubated with EGCG. The LDL was then isolated and its resistance to oxidation was challenged.
The researchers observed an effective increase in LDL resistance to oxidation; a dose-dependent inhibition of HG-mediated long-term glycation of LDL to oxidation was also observed in the LDL-bound ECGC.
“This study suggests that loading plasma with EGCG is an efficient way to increase the content of this phytochemical in LDL, which may imply favourable in vivo activity of EGCG in diabetes,” they wrote in Food Chemistry.
They observed a different mechanism at work from conventional biological activities shown by polyphenols (free radical scavenging and chelating action for metal ions). It seemed to possess a “rather specific and somewhat different degree of antiglycative action and lipoprotein binding activity.”
They believe more investigation is required, and the next stage would be in vivo experiments in an animal model.
Source:
Food Chemistry
DOI: 10.1016/j.foodchem.2010.02.008
Epigallocatechin gallate (EGCG) binds to low-density lipoproteins (LDL) and protects them from oxidation and glycation under high-glucose conditions mimicking diabetes
Authors: Chi-Hao Wu, Chi-Tai Yey, Gow-Chin Yen
