Project description:HYlight is a genetically encoded fluorescent biosensor that ratiometrically monitors fructose 1,6-bisphosphate (FBP), a key glycolytic metabolite. Given the role of glucose in liver cancer metabolism, we expressed HYlight in human liver cancer cells and primary mouse hepatocytes. Through in vitro, in silico, and in cellulo experiments, we showed HYlight's ability to monitor FBP changes linked to glycolysis, not gluconeogenesis. HYlight's affinity for FBP was ~1 µM and stable within physiological pH range. HYlight demonstrated weak binding to dihydroxyacetone phosphate, and its ratiometric response was influenced by both ionic strength and phosphate. Therefore, simulating cytosolic conditions in vitro was necessary to establish a reliable correlation between HYlight’s cellular responses and FBP concentrations. They were found to be in the lower micromolar range, far lower than previous millimolar estimates. Altogether, this biosensor approach offers real-time monitoring of FBP concentrations at single-cell resolution, potentially revolutionizing our understanding of cancer metabolism.
Project description:Non-alcoholic fatty liver disease (NAFLD) influence one of third population around the world. Until now, no effective treatments have been established due to the improper in vitro assays and experimental animal models. By co-culturing human gut and liver cell lines (CaCO2 and HepG2 cells, respectively) interconnected via the microfluidic closed medium circulation loop, we created a gut-liver-on-a-chip (iGLC) platform as an in vitro human model of the gut-liver axis (GLA) in initiation and progression of NAFLD.
Project description:Non-alcoholic fatty liver disease (NAFLD) influence one of third population around the world. Until now, no effective treatments have been established due to the improper in vitro assays and experimental animal models. By co-culturing human gut and liver cell lines (CaCO2 and HepG2 cells, respectively) interconnected via the microfluidic closed medium circulation loop, we created a gut-liver-on-a-chip (iGLC) platform as an in vitro human model of the gut-liver axis (GLA) in initiation and progression of NAFLD.
Project description:BACKGROUND & AIMS: There is mounting evidence that microbes resident in the human intestine contribute to diverse alcohol-associated liver diseases (ALD) including the most deadly form known as alcoholic hepatitis (AH). However, mechanisms by which gut microbiota synergize with excessive alcohol intake to promote liver injury are poorly understood. Furthermore, whether drugs that selectively target gut microbial metabolism can improve ALD has never been tested. METHODS: We used liquid chromatography tandem mass spectrometry to quantify the levels of microbe and host choline co-metabolites in healthy controls and AH patients, and identified the metabolite trimethylamine (TMA) as a gut microbe-derived biomarker of AH. In subsequent studies, we treated mice with non-lethal mechanism-based bacterial choline TMA lyase inhibitors to blunt gut microbe-dependent production of TMA in the context of chronic ethanol administration. Indices of liver injury were quantified by complementary RNA sequencing, biochemical, and histological approaches. In addition, we examined the impact of ethanol consumption and TMA lyase inhibition on gut microbiome structure via 16S rRNA sequencing. RESULTS: We show the gut microbial choline metabolite trimethylamine (TMA) is elevated in AH patients, which is correlated with reduced hepatic expression of the TMA oxygenase flavin-containing monooxygenase 3 (FMO3). Provocatively, we find that small molecule inhibition of gut microbial choline TMA lyase activity protects mice from ethanol-induced liver injury. TMA lyase inhibitor-driven improvement in ethanol-induced liver injury is associated with distinct reorganization of the gut microbiome community and host liver transcriptome. CONCLUSIONS: The microbial metabolite TMA is a biomarker of AH, and blocking TMA production from gut microbes can blunt ALD in mice.
Project description:In this study we tested the ability to predict liver injury from in vitro human pooled hepatocyte data after exposure to thioacetamide (24 hour). We selected thioacetamide, a compound extensively used in various studies for its ability to cause liver injury.