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The gut-brain axis involves several bidirectional pathway communications including microbiome, bacterial metabolites, neurotransmitters as well as immune system and is perturbed both in brain and in gastrointestinal disorders. Consistently, microbiota-gut-brain axis has been found altered in autism spectrum disorder (ASD). We reasoned that such alterations occurring in ASD may impact both on methylation signatures of human host fecal DNA (HFD) and possibly on the types of human cells shed in the stools from intestinal tract giving origin to HFD. To test this hypothesis, we have performed whole genome methylation analysis of HFD from an age-restricted cohort of young children with ASD (N = 8) and healthy controls (N = 7). In the same cohort we have previously investigated the fecal microbiota composition and here we refined such analysis and searched for eventual associations with data derived from HFD methylome analysis. Our results showed that specific epigenetic signatures in human fecal DNA, especially at genes related to inflammation, associated with the disease. By applying methylation-based deconvolution algorithm, we found that the HFD derived mainly from immune cells and the relative abundance of those differed between patients and controls. Consistently, most of differentially methylated regions fitted with genes involved in inflammatory response. Interestingly, using Horvath epigenetic clock, we found that ASD affected children showed both epigenetic and microbiota age accelerated. We believe that the present unprecedented approach may be useful for the identification of the ASD associated HFD epigenetic signatures and may be potentially extended to other brain disorders and intestinal inflammatory diseases. [ABSTRACT FROM AUTHOR]

Accumulating evidence suggests that modifications of gut function and microbiota composition might play a pivotal role in the pathophysiology of several cardiovascular diseases, including heart failure (HF). In this study we systematically analysed gut microbiota composition, intestinal barrier integrity, intestinal and serum cytokines and serum endotoxin levels in C57BL/6 mice undergoing pressure overload by transverse aortic constriction (TAC) for 1 and 4 weeks. Compared to sham-operated animals, TAC induced prompt and strong weakening of intestinal barrier integrity, long-lasting decrease of colon anti-inflammatory cytokine levels, significant increases of serum levels of bacterial lipopolysaccharide and proinflammatory cytokines. TAC also exerted effects on microbiota composition, inducing significant differences in bacterial genera inside Actinobacteria, Firmicutes, Proteobacteria and TM7 phyla as shown by 16S rDNA sequencing of fecal samples from TAC or sham mice. These results suggest that gut modifications represent an important element to be considered in the development and progression of cardiac dysfunction in response to TAC and support this animal model as a valuable tool to establish the role and mechanisms of gut-heart crosstalk in HF. Evidence arising in this field might identify new treatment options targeting gut integrity and microbiota components to face adverse cardiac events. [ABSTRACT FROM AUTHOR]

Cannabinoid type 1 Receptor (CB1) belongs to the GPCR family and it has been targeted, so far, for the discovery of drugs aimed at the treatment of neuropathic pain, nausea, vomit, and food intake disorders. Here, we present the development of the first fluorescent assay enabling the measurement of kinetic binding constants for CB1orthosteric ligands. The assay is based on the use of T1117, a fluorescent analogue of AM251. We prove that T1117 binds endogenous and recombinant CB1 receptors with nanomolar affinity. Moreover, T1117 binding to CB1 is sensitive to the allosteric ligand ORG27569 and thus it is applicable to the discovery of new allosteric drugs. The herein presented assay constitutes a sustainable valid alternative to the expensive and environmental impacting radiodisplacement techniques and paves the way for an easy, fast and cheap high-throughput drug screening toward CB1 for identification of new orthosteric and allosteric modulators. [ABSTRACT FROM AUTHOR]

One of the most fascinating aspects of the field of epigenetics is the emerging ability of environmental factors to trigger epigenetic changes in eukaryotic cells, thus contributing to transient or stable, and potentially heritable, changes in gene expression program in the absence of alteration in DNA sequence. Epigenetic response may result in cell adaptation to environmental stimuli or, in some instances, may contribute to generation or progression of different kind of diseases. A paradigmatic case of disease that is accompanied by multiple epigenetic alterations is gastric cancer, among other relevant examples. In turn, Helicobacter pylori ( Hp) infection has been associated as a leading cause of gastric cancer. One possible hypothesis is that Hp-gastric cell interaction initiates an epigenetic reprogramming of host cell genome that may favor tumorigenesis. Accordingly, an abundance of experimental evidence indicates that several epigenetic alterations underlie the gastric cancerogenesis process and that these alterations represent one of the major hallmarks of gastric cancer. However, several critical questions remain unanswered: Does Hp directly provoke epigenetic alterations? Which mechanisms underlie these phenomena? Based on currently available data, it is often arduous to discriminate between the epigenetic modifications directly triggered by Hp-gastric cell interaction and those alterations that are mediated by inflammation process or by many other molecular and genetic events occurring during the gastric cancer progression. We will review our present knowledge of epigenetic modifications and alterations proven to occur in host cells as a direct consequence of Hp infection. [ABSTRACT FROM AUTHOR]

Inducible nitric oxide synthase (iNOS) expression is altered in gastrointestinal diseases. Helicobacter pylori ( Hp) infection may have a critical role in iNOS disregulation. We undertook this study to investigate possible chromatin changes occurring early during iNOS gene activation as a direct consequence of Hp-gastric cells interaction. We show that Hp infection is followed by different expression and chromatin modifications in gastric cells including (1) activation of iNOS gene expression, (2) chromatin changes at iNOS promoter including decreased H3K9 methylation and increased H3 acetylation and H3K4 methylation levels, (3) selective release of methyl-CpG-binding protein 2 from the iNOS promoter. Moreover, we show that Hp-induced activation of iNOS is delayed, but not eliminated, by the treatment with LSD1 inhibitors. Our data suggest a role for specific chromatin-based mechanisms in the control of human iNOS gene expression upon Hp exposure. [ABSTRACT FROM AUTHOR]

The use/misuse of antibiotics leads to pathological features referring to antibiotic-induced intestinal injury (AIJ), a clinical issue that plays a prominent role in the development of severe digestive disturbances. AIJ is characterized by loss of intestinal architecture and function, dysbiosis and bacterial translocation into the liver, triggering hepatic inflammation. This study aimed at determining the beneficial effect of N-(1-carbamoyl-2-phenylethyl) butyramide (FBA), a butyrate releasing compound, in ceftriaxone-induced intestinal injury. To this purpose, mice receiving ceftriaxone (8 g∙kg−1/die, per os) for five days, were treated with FBA (212,5 mg∙kg−1/die, per os) for five or fifteen days. FBA modulated key players of innate immunity in antibiotic-injured gut tissues, reducing inflammatory process and improving the anti-inflammatory and resolving pattern. FBA also improved colonic architecture and intestinal integrity. Interestingly, we also observed a remodeling of gut microbiota composition related to an increase of metabolic pathways related to lactate and butyrate production. At mechanistic level, FBA induced histone acetylation and increased the expression of GPR43 and monocarboxylate transporter 1 in colon. Our data clearly demonstrated that FBA has multiple converging mechanisms in limiting intestinal and hepatic alterations to counteract AIJ. [ABSTRACT FROM AUTHOR]

Alterations of microbiota-gut-brain axis have been invoked in the pathogenesis of autism spectrum disorders (ASD). Mouse models could represent an excellent tool to understand how gut dysbiosis and related alterations may contribute to autistic phenotype. In this study we paralleled gut microbiota (GM) profiles, behavioral characteristics, intestinal integrity and immunological features of colon tissues in BTBR T + tf/J (BTBR) inbred mice, a well established animal model of ASD. Sex differences, up to date poorly investigated in animal models, were specifically addressed. Results showed that BTBR mice of both sexes presented a marked intestinal dysbiosis, alterations of behavior, gut permeability and immunological state with respect to prosocial C57BL/6j (C57) strain. Noticeably, sex-related differences were clearly detected. We identified Bacteroides, Parabacteroides, Sutterella, Dehalobacterium and Oscillospira genera as key drivers of sex-specific gut microbiota profiles associated with selected pathological traits. Taken together, our findings indicate that alteration of GM in BTBR mice shows relevant sex-associated differences and supports the use of BTBR mouse model to dissect autism associated microbiota-gut-brain axis alteration. [ABSTRACT FROM AUTHOR]