Project description:Essential tremor triggered by reduction of gut bacterial-derived GABA is ameliorated by supplementary of high GABA-producing Lactobacillus plantarum L5
| PRJNA904241 | ENA
Project description:Essential tremor triggered by reduction of gut bacterial-derived GABA is ameliorated by supplementary of high GABA-producing Lactobacillus plantarum L5
Project description:Tertiary lymphoid structures (TLS) correlate with favorable responses to immune checkpoint inhibitors (ICI) in various cancers, yet many patients with TLS-positive tumors are resistant to treatment. Multi-omic profiling of clear cell renal cell carcinoma (ccRCC) and soft tissue sarcoma tumors (STS) reveals an upregulation of gamma-aminobutyric acid (GABA)-related signatures in non-responders to ICI. In ccRCC, TLS from non-responders located near GABA-producing tumor cells, exhibit impaired B cell maturation, reduced IgG production, higher GABA receptor expression and tricarboxylic acid cycle activation. In vitro, exposure of human B cells to GABA reduces HLA-DR expression, proliferation and immunoglobulin secretion by receptor independent and dependent mechanisms. Pharmacological inhibition of GABA-synthesis increases ICI response and immune infiltration, particularly by B cells, in a TLS-positive STS mouse model. Our findings unravel GABA as an immunoregulatory metabolite and provide a rationale for its therapeutic targeting to overcome ICI resistance in patients with TLS-positive tumors.
Project description:Tertiary lymphoid structures (TLS) correlate with favorable responses to immune checkpoint inhibitors (ICI) in various cancers, yet many patients with TLS-positive tumors are resistant to treatment. Multi-omic profiling of clear cell renal cell carcinoma (ccRCC) and soft tissue sarcoma tumors (STS) reveals an upregulation of gamma-aminobutyric acid (GABA)-related signatures in non-responders to ICI. In ccRCC, TLS from non-responders located near GABA-producing tumor cells, exhibit impaired B cell maturation, reduced IgG production, higher GABA receptor expression and tricarboxylic acid cycle activation. In vitro, exposure of human B cells to GABA reduces HLA-DR expression, proliferation and immunoglobulin secretion by receptor independent and dependent mechanisms. Pharmacological inhibition of GABA-synthesis increases ICI response and immune infiltration, particularly by B cells, in a TLS-positive STS mouse model. Our findings unravel GABA as an immunoregulatory metabolite and provide a rationale for its therapeutic targeting to overcome ICI resistance in patients with TLS-positive tumors.
2026-07-08 | GSE273829 | GEO
Project description:Isolation and Characterization of GABA producing Bacteroides strains
Project description:Microbiota-released extracellular vesicles (MEVs) have emerged as a key player in intercellular signaling. However, their involvement in the gut-brain axis has been poorly investigated. In this study, we aimed to investigate the cargo capacity of MEVs for bioactive metabolites and their interactions with the host. Metabolomics analysis identified various neuro-related compounds encapsulated within the 28 MEVs, such as arachidonyl-dopamine, gabapentin, glutamate, and N-acylethanolamines. 29 Metaproteomics unveiled an enrichment of enzymes involved in neuronal metabolism, primarily in the glutamine/glutamate/GABA pathway. The detected neuro-related proteins and metabolites were correlated with Bacteroides spp. A GABA-producing Bacteroides isolate, B. finegoldii, released EVs with a high GABA content (4 µM) as opposed to a low GABA-producing isolate, Phocaeicola massiliensis. MEVs exhibited a dose-dependent paracellular transport and were endocytosed by Caco-2 and hCMEC/D3 cells. RNA-Seq analyses showed that MEVs stimulate several immune pathways while suppressing cell apoptosis process. The in vivo biodistribution confirmed the presence of MEVs in the brain, liver, stomach, and spleen. Overall, our results highlight the ability of MEVs to cross the intestinal and blood-brain barriers to deliver their cargoes to distant organs, including the brain, where it may modulate the organ functionalities. MEVs could be an integral part of microbiome-host communications, with potential implication for the gut-brain axis.
Project description:An aerobic Lactobacillus plantarum culture displayed growth stagnation during early growth. Transcriptome analysis revealed that regain of growth after stagnation correlated with activation of CO2-producing pathways suggesting that limiting CO2-concentration induced stagnation. Analogously providing increased CO2 gas partial pressure during aerobic fermentation prevented the temporal growth stagnation. Keywords: cell type comparison