THE INHIBITORY EFFECT OF SILYBUM MARIANUM (MILK THISTLE) SEEDS EXTRACT ON SERUM ALBUMIN GLYCATION BY GLUCOSE, FRUCTOSE AND GALACTOSE

Abstract

Protein glycation consists of the non-enzymatic attachment of monosaccharides to proteins. This leads to the formation of advanced glycation end products (AGEs) that are held responsible for diabetes complications. There are some drugs that inhibit AGEs, but their usage is limited by side effects. Plant-based therapeutic strategies could be useful in overcoming this limitation. Silybum marianum (Milk thistle), a plant used to treat liver problems, was also proved useful in the treatment of type 2 diabetes. Here we investigated the ability of S. marianum extract to inhibit the in vitro glycation of bovine serum albumin (BSA) by three physiologically relevant monosaccharides, namely glucose, fructose and galactose. BSA was glycated in the absence and in the presence of 0.1 %, 1 % and 5 % S. marianum seeds hydroalcoholic extract. Measurements on fructosamine, AGEs and amyloid cross-β structures formation showed that the plant extract inhibited these processes in the case of the three monosaccharides, especially in the case of glucose and galactose. The inhibition was dose- dependent and time-dependent. Our results demonstrate the ability of the plant extract to inhibit the in vitro glycation of BSA.