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Objective: A large number of studies have highlighted the important role of the gut microbiota in the pathophysiology of neurological disorders, suggesting that its manipulation might serve as a treatment strategy. We hypothesized that the gut microbiota participates in absence seizure development and maintenance in the WAG/Rij rat model and tested this hypothesis by evaluating potential gut microbiota and intestinal alterations in the model, as well as measuring the impact of microbiota manipulation using fecal microbiota transplantation (FMT). Methods: Initially, gut microbiota composition and intestinal histology of WAG/Rij rats (a well‐recognized genetic model of absence epilepsy) were studied at 1, 4, and 8 months of age in comparison to nonepileptic Wistar rats. Subsequently, in a second set of experiments, at 6 months of age, untreated Wistar or WAG/Rij rats treated with ethosuximide (ETH) were used as gut microbiota donors for FMT in WAG/Rij rats, and electroencephalographic (EEG) recordings were obtained over 4 weeks. At the end of FMT, stool and gut samples were collected, absence seizures were measured on EEG recordings, and microbiota analysis and histopathological examinations were performed. Results: Gut microbiota analysis showed differences in beta diversity and specific phylotypes at all ages considered and significant variances in the Bacteroidetes/Firmicutes ratio between Wistar and WAG/Rij rats. FMT, from both Wistar and ETH‐treated WAG/Rij donors to WAG/Rij rats, significantly decreased the number and duration of seizures. Histological results indicated that WAG/Rij rats were characterized by intestinal villi disruption and inflammatory infiltrates already at 1 month of age, before seizure occurrence; FMT partially restored intestinal morphology while also significantly modifying gut microbiota and concomitantly reducing absence seizures. Significance: Our results demonstrate for the first time that the gut microbiota is modified and contributes to seizure occurrence in a genetic animal model of absence epilepsy and that its manipulation may be a suitable therapeutic target for absence seizure management. [ABSTRACT FROM AUTHOR]

Background Helicobacter pylori infection causes chronic oxidative stress on gastric mucosa, thereby causing mucosal damage and increasing the risk of gastric adenocarcinoma. Nrf2 is an important transcription factor, regulating the antioxidant response in the cells. Nrf2 signaling is repressed by Keap1 at basal condition and induced by oxidative stress. The aim of our study was to analyze whether the H. pylori proteins interfered in the Nrf2/ Keap1 pathway. Material and Methods Gene expression in AGS cells transiently and stably transfected was analyzed by real-time PCR. Immunoprecipitation and immunofluorescence assays were performed to investigate the ability of H. pylori proteins to interfere with the Nrf2 pathway. Results We demonstrated that the H. pylori Hsp B protein interferes with Nrf2/ Keap1 pathway. When HspB was transiently transfected in AGS cells, a significant increase in Keap1 gene expression was induced. The same result was observed when AGS cells were Hsp B stably transfected. In this case, the increase in Keap1 was associated with reduced gene expression of Nrf2, and of the antioxidant enzymes superoxide dismutase, hemeoxygenase-1, and phase II detoxifying enzyme NAD(P)H:quinone oxidoreductase-1. Immunoprecipitation and immunofluorescence assays confirmed the ability of Hsp B protein to interfere with the Nrf2 pathway. Lastly, in HspB-transfected AGS cells, sustained activation of IL-8, COX2, MMP3, and MMP7 was demonstrated. Conclusion The results here reported suggest that inhibited nuclear translocation of Nrf2, associated with induced inflammation and increased production of MMPs, might represent a condition enhancing the risk of gastric adenocarcinoma. [ABSTRACT FROM AUTHOR]

AV119 is a patented blend of two sugars from avocado that can induce human β-defensin-2 production by normal human keratinocytes. In this study, we analysed the effect of AV119 on growth and invasiveness of Malassezia furfur, a dimorphic, lipid-dependent yeast that is part of the normal human cutaneous commensal flora. The ability to modulate the expression of the proinflammatory and immunomodulatory cytokines in normal human keratinocytes was also investigated. Microbiological assay demonstrated that this sugar induced the aggregation of yeast cells and inhibited the invasiveness of M. furfur, without affecting its growth. Real-time PCR analysis demonstrated that AV119 was able to modulate the HBD-2 response in treated keratinocytes, reaching a maximum after 48-h treatment, and to induce the recovery of a satisfactory proinflammatory response in human keratinocytes. As AV119 can induce aggregation of yeast cells, thus inhibiting their penetration into the keratinocytes, the sugar could be used in the preparation of cosmetics or pharmacological drugs to inhibit colonization of the skin by pathogenic strains of M. furfur. [ABSTRACT FROM AUTHOR]

Serum deprivation induced in human lymphoblastoid Raji cells oxidative stress-associated apoptotic death and G0/G1 cell cycle arrest. Addition into culture medium of the immunomodulatory protein Seminal vesicle protein 4 (SV-IV) protected these cells against apoptosis but not against cycle arrest. The antiapoptotic activity was related to: (1) decrease of endocellular reactive Oxygen species (ROS) (2) increase of mRNAs encoding anti-oxidant enzymes (catalase, G6PD) and antiapoptotic proteins (survivin, cox-1, Hsp70, c-Fos); (3) decrease of mRNAs encoding proapoptotic proteins (c-myc, Bax, caspase-3, Apaf-1). The biochemical changes underlaying these effects were probably induced by a protein tyrosine kinase (PTK) activity triggered by the binding of SV-IV to its putative plasma membrane receptors. The ineffectiveness of SV-IV to abrogate the cycle arrest was accounted for by its downregulating effects on D1,3/E G1-cyclins and CdK2/4 gene expression, ppRb/pRb ratio, and intracellular ROS concentration. In conclusion, these experiments: (1) prove that SV-IV acts as a cell survival factor; (2) suggest the involvement of a PTK in SV-IV signaling; (3) point to cell cycle-linked enzyme inhibition as responsible for cycle arrest; (4) provide a model to dissect the cycle arrest and apoptosis induced by serum withdrawal; (5) imply a possible role of SV-IV in the survival of hemiallogenic implanting embryos. J. Cell. Physiol. 212:610–625, 2007. © 2007 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Donnarumma G, Paoletti I, Buommino E, Tufano MA, Baroni A.α-MSH reduces the internalization ofStaphylococcus aureusand down-regulates HSP 70, integrins and cytokine expression in human keratinocyte cell lines.α-melanocyte-stimulating hormone (α-MSH) is a neuropeptide predominantly produced by the pituitary gland, but it is also generated by many extra-pituitary cells including keratinocytes of the skin. This neuropeptide has anti-inflammatory and antimicrobial effects and probably contributes in innate immunity.Staphylococcus aureusis the aetiological agent of a wide range of infections in humans. Colonization of human skin byS.aureusis a characteristic feature of several skin diseases and is often followed by tissue invasion and severe cell damage. The aim of our study was to detect a possible role ofα-MSH during the early infection stages in the adhesion and penetration of keratinocytes before cell damage. Our data demonstrated thatα-MSH precociously down-regulates the production of integrins such asβ1 and heat shock surface protein 70, essential molecules for the entry ofS.aureus. Moreover, in our experimental model,α-MSH induces the down-regulation of the pro-inflammatory cytokine expression and of the adhesion molecules in keratinocytes activated byS.aureus. Our data suggest thatα-MSH plays a protective role in the skin by reducing infection and the inflammatory process. [ABSTRACT FROM AUTHOR]