Evaluation of glutathione reductase activity in colon tissue of patients with irritable bowel syndrome

Abstract

Irritable bowel syndrome (IBS) is known as one of the most common irritating gastrointestinal disorders. The mechanism behind IBS is still under investigation and it is thought that it may arose from multi factors among which free radicals have been previously mentioned. Studies have found an association between oxidative stress and IBS; however, little is known about the mechanisms and oxidative stress components status during IBS. One of the key factors playing a central role in oxidative stress network is glutathione reductase (GR). Here we report the GR activity in colon tissue samples during IBS to explore a part of contributing components in IBS pathogenesis. The GR enzyme activity was measured in 15 active IBS colon biopsy samples and was compared to our best available age and sex matched colorectal tissue samples from normal marginal tissue of resected colon cancers (n=15). The enzyme activity in the two groups was determined and compared using a commercial GR Assay Kit (Cayman chemical). A significant decrease in GR activity among IBS tissue samples was observed compared to anatomically normal marginal colon tissue samples (p=0.007). Lower GR activity may increase oxidized glutathione there by in turn could contribute as a main component in oxidative stress network. The lower GR activity results in hampered defense mechanism against produced free radical species. This finding may clarify a part of IBS pathogenesis.