Irritable bowel syndrome (IBS) is the most common functional gastrointestinal disorder yet it still lacks effective prevention therapies. The aim of this study is to determine whether a novel prebiotic blend (PB) composed of fructo-oligosaccharide (FOS), galactooligosaccharide (GOS), inulin and anthocyanins could be effective in preventing the development of IBS. We explored the possible mechanisms both in animal and in cells. Post-infectious IBS models in C57BL/6 mice were established and were pretreated with the PB, PB and probiotic strains 8 weeks in advance of infection. Eight weeks after infection, intestinal tissues were collected for assessing histomorphology, visceral sensitivity, barrier function, pro-inflammatory cytokines expression and proteomics analysis. Fecal samples were also collected for microbiota analysis. The pro-inflammatory cytokines expression in Caco-2 cells were evaluated after co-incubation with PB and Salmonella typhimurium 14028. The results showed that PB significantly decreased the pro-inflammatory cytokines both in infected Caco-2 cells and PI-IBS models. The loss of body weight, decreased expression of tight junction protein Occludin (OCLN), and changes of the microbiota composition induced by infections could be greatly improved by PB intervention (p < 0.05). The proteomics analysis revealed that this function was associated with Peroxisome proliferator-activated receptor (PPAR)γ pathway.

Summary. (E)-4-Hydroxy-2-nonenal (HNE), a cytotoxic end-product of lipid peroxidation, is present in significant amounts in human semen (0·902 ± 0·190μm; mean ± s.e.; n = 18). The addition of the divalent cation ionophore A23187 to suspensions of human spermatozoa resulted in increased production of HNE. Exogenous HNE was powerfully spermicidal and as little as 50μm caused an irreversible loss of motility of human spermatozoa within minutes. The addition of human seminal plasma protected spermatozoa from the toxic effects of HNE. Keywords: (E)-4-Hydroxy-2-nonenal; lipid peroxidation; cytotoxicity; human seminal plasma

(E)-4-Hydroxy-2-nonenal (HNE), a cytotoxic propagation product of lipid peroxidation, is present in the synovial fluid (0.54 (0.19) mumol/l; mean (SE), n = 9) and plasma (0.34 (0.09) mumol/l, n = 9) of patients with rheumatoid arthritis. This compound was also found in the synovial fluid (0.24 (0.19) mumol/l, n = 9) and plasma (0.09 (0.03) mumol/l, n = 9) of patients with osteoarthritis. The concentration of HNE in the plasma of patients with rheumatoid arthritis was significantly greater than in patients with osteoarthritis.