Publications by authors named "Volker Elste"

Establishing intake recommendations for vitamin C remains a challenge, as no suitable functional parameter has yet been agreed upon. In this report, we review the emerging evidence on neutrophil motility as a possible marker of vitamin C requirements and put the results in perspective with other approaches. A recent in vitro study showed that adequate levels of vitamin C were needed for this function to work optimally when measured as chemotaxis and chemokinesis.

View Article and Find Full Text PDF

Ascorbigen (ABG) is a natural compound that represents a breakdown product of the glucosinolates that are present in Brassica vegetables. It is postulated that ABG may have anticarcinogenic activity; however, the underlying molecular and cellular mechanisms are largely unknown. In the present study we investigated the effect of ABG on the mRNA and enzyme activity levels of NADPH-quinone oxidoreductase (NQO1), which is centrally involved in the detoxification of xenobiotics, in cultured liver cells and in rats.

View Article and Find Full Text PDF

Carotenoids are currently investigated regarding their potential to lower the risk of chronic disease and to combat vitamin A deficiency in humans. These plant-derived compounds must be cleaved and metabolically converted by intrinsic carotenoid oxygenases to support the panoply of vitamin A-dependent physiological processes. Two different carotenoid-cleaving enzymes were identified in mammals, the classical carotenoid-15,15'-oxygenase (CMO1) and a putative carotenoid-9',10'-oxygenase (CMO2).

View Article and Find Full Text PDF

Background: This study investigated the antiobesity effects of TEAVIGO, a product providing the most abundant green tea catechin, epigallocatechin gallate (EGCG), in a pure form. Two models of diet-induced obesity and an in vitro adipocyte differentiation assay were employed.

Methods: Prevention and regression of diet-induced obesity by dietary supplementation with EGCG was studied in C57BL/6J mice and Sprague-Dawley rats, respectively.

View Article and Find Full Text PDF

Catechins, compounds derived from green tea, have been shown to reduce plasma cholesterol levels and the rate of cholesterol absorption. We investigated the dose response and the mechanism of action of epigallocatechin gallate (EGCG) on these parameters in rats. Wistar rats were fed a diet high in cholesterol and fat containing either none, 0.

View Article and Find Full Text PDF