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Recent evidence highlights Parkinson's disease (PD) initiation in the gut as the prodromal phase of neurodegeneration. Gut impairment due to microbial dysbiosis could affect PD pathogenesis and progression. Here, we propose a two-hit model of PD through ceftriaxone (CFX)-induced dysbiosis and gut inflammation before the 6-hydroxydopamine (6-OHDA) intrastriatal injection to mimic dysfunctional gut-associated mechanisms preceding PD onset. Therefore, we showed that dysbiosis and gut damage amplified PD progression, worsening motor deficits induced by 6-OHDA up to 14 days post intrastriatal injection. This effect was accompanied by a significant increase in neuronal dopaminergic loss (reduced tyrosine hydroxylase expression and increased Bcl-2/Bax ratio). Notably, CFX pretreatment also enhanced systemic and colon inflammation of dual-hit subjected mice. The exacerbated inflammatory response ran in tandem with a worsening of colonic architecture and gut microbiota perturbation. Finally, we demonstrated the beneficial effect of post-biotic sodium butyrate in limiting at once motor deficits, neuroinflammation, and colon damage and re-shaping microbiota composition in this novel dual-hit model of PD. Taken together, the bidirectional communication of the microbiota-gut-brain axis and the recapitulation of PD prodromal/pathogenic features make this new paradigm a useful tool for testing or repurposing new multi-target compounds in the treatment of PD.

The spatio-temporal regulation of genes involved in the synthesis and degradation of D-serine and D-aspartate such as serine racemase (SR), D-amino acid oxidase (DAO), G72 and D-aspartate oxidase (DDO), play pivotal roles in determining the correct levels of these D-amino acids in the human brain. Here we provide a comprehensive analysis of mRNA expression and DNA methylation status of these genes in post-mortem samples from hippocampus, dorsolateral prefrontal cortex, and cerebellum from patients with schizophrenia and non-psychiatric controls. DNA methylation analysis was performed at an ultradeep level, measuring individual epialleles frequency by single molecule approach. Differential CpG methylation and expression was detected across different brain regions, although no significant correlations were found with diagnosis. G72 showed the highest CpG and non-CpG methylation degree, which may explain the repression of G72 transcription in the brain regions considered here. Conversely, in line with the sustained SR mRNA expression in the analyzed areas, very low methylation levels were detected at this gene's regulatory regions. Furthermore, for DAO and DDO, our single-molecule methylation approach demonstrated that analysis of epiallele distribution was able to detect differences in DNA methylation representing area-specific methylation signatures, which are likely not detectable with targeted or genome-wide classic methylation analyses.

Figure S2. Regression analysis associating the degree of methylation with mRNA expression levels of the Ddo gene. Regression analysis associating DNA methylation and mRNA expression of Ddo gene is shown in each analyzed brain area during development. Ddo mRNA expression is normalized to the mean values for two housekeeping genes and expressed as 2–∆Ct values. The three mice for each time point (P1 = red; P15 = blue; P30 = yellow; P60 = green) are indicated. Statistical analyses were performed using Pearson correlation. * p ≤ 0.05 (PDF 86 kb)

Urinary tract infections (UTIs) and catheter-associated UTIs (CAUTIs) are the principal hospital-acquired infections. Proteus mirabilis is characterized by several virulence factors able to promote adhesion and biofilm formation and ameliorate the colonization of urinary tract and the formation of crystalline biofilms on the abiotic surface of the urinary catheters. Since, to date, the role of P. mirabilis in the etiopathogenesis of different types of urinary tract infections is not well established, in this study we sought to characterize two different clinically isolated strains of P. mirabilis (PM1 and PM2) with distinctive phenotypes and analyzed various virulence factors possibly implicated in the ability to induce UTIs and CAUTIs. In particular, we analyzed motility, biofilm formation both on abiotic and biotic surfaces of PM1 and PM2 and paralleled these parameters with the ability to induce an inflammatory response in an epithelial cell model. Results showed that PM1 displayed major motility and a capacity to form biofilm and was associated with an anti-inflammatory response of host cells. Conversely, PM2 exhibited lack motility and a had slower organization in biofilm but promoted an increase of proinflammatory cytokine expression in infected epithelial cells. Our study provides data useful to start uncovering the pathologic basis of P. mirabilis-associated urinary infections. The evidence of different virulence factors expressed by PM1 and PM2 highlights the possibility to use precise and personalized therapies targeting specific virulence pathways.

Insects could be potential nutritional sources both for humans and animals. Among these, Hermetia illucens, with good amount of chitin and proteins, represents a suitable diet replacement for laying hens. Little is known about insect diet effects on the microbial ecology of the gastrointestinal tract and bacterial metabolites production. In this study we investigated the effect of H. illucens larvae meal administration on cecal microbiota and short chain fatty acids (SCFAs) production in laying hens. 16S rDNA sequencing showed strong differences between cecal microbiota of soybean (SD) and insect diet (ID) groups both in type and relative abundance (unweighted and weighted beta diversity) of microbial species. In particular, Bacteroides plebeius, Elusimicrobium minutum, Alkaliphilus transvaalensis, Christensenella minuta, Vallitalea guaymasensis and Flavonifractor plautii represented the principal contributors of changes in gut microbiota composition of ID group (FDR p-values

Crohn’s disease (CD) is a chronic inflammation of the intestinal mucosa, characterized by periods of acute recurrence and remission. Depending on the specific region affected, CD is classified as ileal CD or colonic CD. It is largely accepted that the intestinal microbiota is involved in the onset of the pathology. Indeed, a reduced immune tolerance to components of the intestinal commensal microbiota and inflammation of the intestinal barrier typifies patients with CD. Several studies have shown defective expression of intestinal antimicrobial peptides (AMPs) in patients with CD compared to controls, particularly defensins. A reduction in α-defensins is observed in ileal CD, while β-defensins are increased in colonic CD. In addition to an immunological basis, the disease is frequently associated with genetic alterations including mutations of NOD2 gene. Several therapeutic strategies to circumvent the dysfunction observed in CD are currently under investigation. These include the use of delivery systems to administer endogenous AMPs and the engineering of peptidomimetics that could ameliorate the severity of CD. In this review, the role defensins play in CD and the strategies aimed at overcoming bacterial resistance will be discussed.

Introduction: LPS induces the release of COX-2 by intestinal mucosal cells, because it is now emerging that bacteria may induce alteration of epigenetic patterns in host cells, we have investigated whether LPS induced COX-2 activation in human intestinal epithelial cells (HT-29) involves changes of histone modifications and/or DNA methylation at COX-2 gene regulatory region. We hypothesized that LPS infection may have a direct impact on the epigenetic status of COX-2 gene in HT-29 cells and that LPS-induced COX-2 activation may be mediated by rapid changes at COX-2 gene regulatory regions. LPS induces epigenetic events that include both chromatin and DNA methylation modifications after COX-2 activation in HT-29 cells. Material e Methods: HT-29 treated with LPS and not were used for Relative Quantitative expression analysis in real time PCR. Quantitative ChIP analysis was performed on COX-2 promoter for histone modifications analysis. Gene silencing by RNA interference were used for determine the epigenetic mechanism of COX-2 activation LPS-dependent. DNA methylation analysis of COX-2 promoter was performed by MALDI-TOF. Results: We described the chromatin and DNA methylation changes occurring at the COX-2 gene in HT-29 cells as direct consequences of LPS exposure. LPS infection is followed by several expression, chromatin and DNA modifica- tion events including: activation of the COX-2 gene; transient gradual increase of H3K4 dimethylation and decrease of H3K9 dimethylation and H3K27 trimethylation in correspondence of the later 2h peak of COX-2 mRNA expression; rapid cyclical DNA methylation/demethylation events at specific CpG sites at COX-2 gene-regulatory region mainly in concomitance with the early expression gene. Discussion e Conclusion: We have investigated the epigenetic changes occurring at the COX-2 locus during the first 24 h after exposure of human HT29 to LPS and, thus directly attributable to host-parasite interaction. 2h of LPS exposure of HT29 cells induces the JMJD3 binding to COX-2 promoter region and following removing of H3K27me3 associated to expression of COX-2. Most of chromatin marks are then restored in a short time after LPS infection with the exception of LSD1 that no longer bind to COX-2 promoter, possibly responsible of not H3K9me2 demethylation underlying a more condensed chromatin state at the COX-2 gene. In addiction, a cyclic DNA methylation/demethilation of COX-2 promoter, observed in LPS-HT29 cells treatment, can to be associated at stable expression of gene. It will be very important to investigate whether the observed decrease of JMJD3 levels at COX-2 in response to long treatment with LPS may occur in intestinal mucosa and may represent a stable epigenetic mark during long exposition to microorganisms.