Targeted metabolomics reveals aberrant profiles of serum bile acids in patients with schizophrenia

Association of Blood Metabolomics Biomarkers with Brain Metabolites and Patient-Reported Outcomes as a New Approach in Individualized Diagnosis of Schizophrenia

Given its polygenic nature, there is a need for a personalized approach to schizophrenia. The aim of the study was to select laboratory biomarkers from blood, brain imaging, and clinical assessment, with an emphasis on patients' self-report questionnaires. Metabolomics studies of serum samples from 51 patients and 45 healthy volunteers, based on the liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS/MS), led to the identification of 3 biochemical indicators (cortisol, glutamate, lactate) of schizophrenia. These metabolites were sequentially correlated with laboratory tests results, imaging results, and clinical assessment outcomes, including patient self-report outcomes. The hierarchical cluster analysis on the principal components (HCPC) was performed to identify the most homogeneous clinical groups. Significant correlations were noted between blood lactates and 11 clinical and 10 neuroimaging parameters. The increase in lactate and cortisol were significantly associated with a decrease in immunological parameters, especially with the level of reactive lymphocytes. The strongest correlations with the level of blood lactate and cortisol were demonstrated by brain glutamate, N-acetylaspartate and the concentrations of glutamate and glutamine, creatine and phosphocreatine in the prefrontal cortex. Metabolomics studies and the search for associations with brain parameters and self-reported outcomes may provide new diagnostic evidence to specific schizophrenia phenotypes.

Crohn's Disease-Associated Pathogenic Mutation in the Manganese Transporter ZIP8 Shifts the Ileal and Rectal Mucosal Microbiota Implicating Aberrant Bile Acid Metabolism

BACKGROUND

A pathogenic mutation in the manganese transporter ZIP8 (A391T; rs13107325) increases the risk of Crohn's disease. ZIP8 regulates manganese homeostasis and given the shared need for metals between the host and resident microbes, there has been significant interest in alterations of the microbiome in carriers of ZIP8 A391T. Prior studies have not examined the ileal microbiome despite associations between ileal disease and ZIP8 A391T.

METHODS

Here, we used the Pediatric Risk Stratification Study (RISK)  cohort to perform a secondary analysis of 16S ribosomal RNA gene sequencing data obtained from ileal and rectal mucosa to study associations between ZIP8 A391T carrier status and microbiota composition.

RESULTS

We found sequence variants mapping to Veillonella were decreased in the ileal mucosa of ZIP8 A391T carriers. Prior human studies have demonstrated the sensitivity of Veillonella to bile acid abundance. We therefore hypothesized that bile acid homeostasis is differentially regulated in carriers of ZIP8 A391T. Using a mouse model of ZIP8 A391T, we demonstrate an increase in total bile acids in the liver and stool and decreased fibroblast growth factor 15 (Fgf15) signaling, consistent with our hypothesis. We confirmed dysregulation of FGF19 in the 1000IBD cohort, finding that plasma FGF19 levels are lower in ZIP8 A391T carriers with ileocolonic Crohn's disease.

CONCLUSIONS

In the search for genotype-specific therapeutic paradigms for patients with Crohn's disease, these data suggest targeting the FGF19 pathway in ZIP8 A391T carriers. Aberrant bile acid metabolism may precede development of Crohn's disease and prioritize study of the interactions between manganese homeostasis, bile acid metabolism and signaling, and complicated ileal Crohn's disease.

Deoxycholic acid inhibits Staphylococcus aureus-induced endometritis through regulating TGR5/PKA/NF-κB signaling pathway

Endometritis, a common gynecological disease, is the most common cause of infertility. As a natural metabolite of gut microbiota, deoxycholic acid (DCA) has been reported to have anti-inflammatory function. In the current study, the protective role of DCA on Staphylococcus aureus (S.aureus)-induced endometritis was tested. In vivo, DCA inhibited uterine histological change, MPO activity, endometrial barrier disruption, and inflammatory cytokine production induced by S.aureus. In vitro, DCA suppressed S.aureus-induced TNF-α and IL-1ß production in mouse endometrial epithelial cells (mEECs). Also, DCA markedly suppressed S.aureus-induced NF-κB activation. Takeda G protein-coupled receptor 5 (TGR5)is a critical bile acid membranereceptor that mainly regulated the cyclic AMP (cAMP)/protein kinase A (PKA)signaling pathway to inhibit NF-κB activation. We found DCA significantly increased TGR5 and PKA expression and S.aureus-induced inflammatory cytokine production and NF-κB activation were prevented by TGR5 inhibitor and PKA inhibitor. In conclusion, DCA protected S.aureus-induced endometritis by regulating TGR5/PKA/NF-κB signaling pathway.