Over the last decade fundamentally new features have been revealed for the participation of glutathione and glutathione-dependent enzymes (glutathione transferase and glutaredoxin) in cell...

S-glutathionylation and S-nitrosylation are reversible post-translational modifications on the cysteine thiol groups of proteins, which occur in cells under physiological conditions and oxidative/nitrosative stress both spontaneously and enzymatically. They are important for the regulation of the functional activity of proteins and intracellular processes. Connecting link and “switch” functions between S-glutathionylation and S-nitrosylation may be performed by GSNO, the generation of which depends on the GSH content, the GSH/GSSG ratio, and the cellular redox state. An important role in the regulation of these processes is played by Trx family enzymes (Trx, Grx, PDI), the activity of which is determined by the cellular redox status and depends on the GSH/GSSG ratio. In this review, we analyze data concerning the role of GSH/GSSG in the modulation of S-glutathionylation and S-nitrosylation and their relationship for the maintenance of cell viability.

We report that the results of our study indicate that Lactobacillus brevis 47 f strain isolated from the faeces of a healthy individual prevents the manifestations of experimental mucositis induced by treatment of Balb/c mice with the anticancer drug 5-fluorouracil (5 FU; 100 mg/kg i.p. × 3 days). The presence of damage to the intestine and the colon was determined by a morphometric analysis of specimens including the height of villi, the amount of goblet cells and infiltrating mononuclear cells, and the expression of the proliferative Ki-67 antigen. Changes in the lipid peroxidation in the blood and the intestine were determined by severalfold increase of the concentration of malonic dialdehyde. Oral administration of L. brevis 47 f strain prior to 5 FU decreased the drug-induced morphological and biochemical changes to their respective physiological levels; the ability of intestinal epitheliocytes to express Ki-67 was partially restored. These effects of L. brevis 47 f strain were more pronounced or similar to those of the reference compound Rebamipid, a quinoline derivative known to protect the gut from drug-induced toxicity. Thus, the new lactobacilli strain attenuates the severity of 5 FU-induced enteropathy.