Astaxanthin may protect cells exposed to high-glucose levels, as occurs with diabetes, from the oxidative stress associated with abnormally high blood sugar levels, according to findings published in the Journal of Agricultural and Food Chemistry. Such high blood sugar levels and the oxidative stress that goes along with it are linked to many diabetic complications including kidney disease.
“On the basis of all the evidence, we propose that the modulation of oxidative stress, inflammation, and apoptosis is the likely mechanism underlying the beneficial role of astaxanthin on diabetic nephropathy [kidney disease] in high-glucose-treated [cells],” wrote the researchers from Busan Women’s College (Korea) and University of Toyama (Japan).
“Consequently, we conclude from these studies that astaxanthin could be an effective, functional supplement as an anti-diabetic phytochemical,” they added.
A rosy future for the pink pigment?
The global astaxanthin market is estimated at about €190m globally, most of which is used as a pigment to enhance the pink coloration of fish such as salmon. The human uses market is growing and estimated at about €20-€30m.
Its main health benefits are eye and skin health although it has also been linked to joint health and central nervous system health and is said to have an antioxidant payload 500 times that of vitamin E.
Most astaxanthin is derived from the algae, Haematococcus pluvialis, which is commonly consumed by fish and crustaceans and is responsible for their pink coloration.
The Korean and Japanese researchers investigated if the pigment could protect against the deleterious effects of oxidative stress associated with elevated blood glucose levels.
“Under diabetic conditions, many damaged molecules including DNA, lipid peroxidation products, and advanced glycation end products (AGEs) eventually lead to pathological diabetic complications including nephropathy,” they explained.
Cells were treated in a high-glucose mix, and then exposed to astaxanthin. According to the findings, the antioxidant effectively suppressed lipid peroxidation, total reactive species, superoxide, and nitric oxide levels. Markers of inflammation, including inducible nitric oxide synthase (iNOS) and cyclooxygeanase-2 (COX-2) were also suppressed.
“Considering the beneficial actions of astaxanthin are intracellular events, it would be interesting and important to discuss something about the permeability of this lipophilic astaxanthin,” wrote the researchers.
“Although we have no quantitative information on the intracellular astaxanthin level in the present study, based on [other] work, we expect that sufficient amounts of astaxanthin were intracellularly localized to exert its protection against oxidative stress, inflammation, and apoptosis,” they added.
“We believe we show, for the first time, that astaxanthin ameliorated oxidative stress, inflammation, and apoptosis in these cells,” concluded the researchers.
Source: Journal of Agricultural and Food Chemistry
Published online ahead of print, Article ASAP, doi: 10.1021/jf9019745
“Protection against Oxidative Stress, Inflammation, and Apoptosis of High-Glucose-Exposed Proximal Tubular Epithelial Cells by Astaxanthin”
Authors: Y.J. Kim, Y.A. Kim, T. Yokozawa