Khan, Z. A. | bioRxiv Science

bioRxiv2024

Genderized Gut and Oral Microbiome Shifts: Uncovering Sex-Specific Dysbiosis in Pancreatic Cancer

BackgroundPancreatic ductal adenocarcinoma (PDAC) is one of the deadliest cancers, responsible for approximately 466,000 deaths globally in 2020. Its incidence increases by about 1% annually, with a higher occurrence in males than females. While differences in immune responses and tumor biology between sexes have been explored, the role of the microbiome in gender-specific PDAC progression is still unclear. Investigating these differences could offer crucial insights for personalized treatment strategies for males and females. MethodsThis study reanalyzed oral and gut microbiome data from BioProject: PRJNA832909, comprising 191 samples from PDAC patients and healthy controls. Using shotgun metagenomic sequencing, we examined gender-specific bacterial signatures. Alpha diversity (richness) and beta diversity (community composition) were analyzed. Differentially abundant bacterial taxa were identified via LEfSe, and gender-specific bacterial panels were validated using CombiROC. ResultsAlpha diversity analysis revealed significant differences in microbial richness, particularly between male and female PDAC patients and their healthy controls. Beta diversity demonstrated distinct microbial shifts between the PDAC and control groups across genders. LEfSe identified several pathogenic bacteria contributing to gender-specific dysbiosis, including Streptococcus, Fusobacterium, and Prevotella. Shared and sex-specific bacterial species in PDAC were highlighted through Venn diagram analysis. CombiROC validated the predictive ability of these bacterial markers, with AUC values exceeding 0.90 for both sexes. ConclusionThis study uncovered gender-specific microbial patterns in PDAC patients, potentially influenced by sex-specific immune responses. These findings provide important insights into the progression of PDAC and support sex-targeted diagnostic and therapeutic interventions. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=77 SRC="FIGDIR/small/616338v1_ufig1.gif" ALT="Figure 1"> View larger version (41K): org.highwire.dtl.DTLVardef@4b1d97org.highwire.dtl.DTLVardef@183c267org.highwire.dtl.DTLVardef@1500547org.highwire.dtl.DTLVardef@8a854c_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

bioRxiv2021

Symptomatic and Disease-Modifying Effects of GABAA Receptor Positive Allosteric Modulation in a Mouse Model of Chronic Stress

Chronic stress is a risk factor for Major depressive disorder (MDD), and in rodents, it recapitulates human behavioral, cellular and molecular changes. In MDD and after chronic stress, neuronal dysfunctions and deficits in GABAergic signaling are observed and responsible for symptom severity. GABA signals predominantly through GABAA receptors (GABAA-R) composed of various subunit types that relate to downstream outcomes. Activity at 2-GABAA-Rs contributes to anxiolytic properties, 5-GABAA-Rs to cognitive functions, and 1-GABAA-Rs to sedation. Therefore, a therapy aiming at increasing 2- and 5-GABAA-Rs activity, but devoid of 1-GABAA-R activity, has potential to address several symptomologies of depression while avoiding side effects. This study investigated the activity profiles and behavioral efficacy of two molecules enantiomers of each other (GL-II-73 and GL-I-54), separately and as a racemic mixture (GL-RM), and potential disease-modifying effects on neuronal morphology. Results confirm GL-I-54 and GL-II-73 exert positive allosteric modulation at the 2-, 3-, 5-GABAA-Rs and 5-containing GABAA-Rs, respectively, and have anti-depressant and pro-cognitive effects independently. Using unpredictable chronic mild stress (UCMS) in male and female mice (n=12/group), we show that acute and chronic administration of GL-RM combined the anti-depressant and pro-cognitive effects of each enantiomer, although at lower doses avoiding sedation. Morphology studies showed reversal of spine density loss caused by UCMS after chronic GL-RM treatment at apical and basal dendrites of the PFC and CA1. Together, these results support using a racemic mixture with combined 2-, 3-, 5-GABAA-R profile to reverse chronic stress-induced mood symptoms, cognitive deficits, and with anti-stress neurotrophic effects.

neuroscience↗