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Cell Stem Cell Jul 2018Chronic liver injury can cause cirrhosis and impaired liver regeneration, impairing organ function. Adult livers can regenerate in response to parenchymal insults, and...
Chronic liver injury can cause cirrhosis and impaired liver regeneration, impairing organ function. Adult livers can regenerate in response to parenchymal insults, and multiple cellular sources have been reported to contribute to this response. In this study, we modeled human chronic liver injuries, in which such responses are blunted, without genetic manipulations, and assessed potential contributions of non-parenchymal cells (NPCs) to hepatocyte regeneration. We show that NPC-derived hepatocytes replenish a large fraction of the liver parenchyma following severe injuries induced by long-term thioacetamide (TAA) or 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) treatment. Through lineage tracing of biliary epithelial cells (BECs), we show that BECs are a source of new hepatocytes and gain an Hnf4αCK19 bi-phenotypic state in periportal regions and fibrotic septa. Bi-phenotypic cells were also detected in cirrhotic human livers. Together, these data provide further support for hepatocyte regeneration from BECs without genetic interventions and show their cellular plasticity during severe liver injury.
Topics: Animals; Chronic Disease; Epithelial Cells; Hepatocytes; Humans; Liver Cirrhosis; Mice; Mice, Inbred Strains; Thioacetamide
PubMed: 29937200
DOI: 10.1016/j.stem.2018.05.022 -
Free Radical Biology & Medicine Jan 2021Liver fibrosis is a reversible wound-healing response to acute or chronic liver injury that can progress to cirrhosis and liver cancer. Finding new strategies for...
Liver fibrosis is a reversible wound-healing response to acute or chronic liver injury that can progress to cirrhosis and liver cancer. Finding new strategies for prevention and management of liver fibrosis is urgently needed. It is known that hepatic stellate cell (HSC) is the primary source of extracellular matrix that drives liver fibrosis progression. Herein, we carried out a comprehensive secretome profiling to identify NMN-induced changes in secretory proteins and found that NMN suppressed the secretion of profibrotic protein and oxidoreductase in activated HSC (LX-2) cells, while real-time quantitative PCR analysis revealed that NMN downregulated profibrotic gene expression, resulting in HSC inactivation. Next, we demonstrated that nicotinamide mononucleotide (NMN) reduced the accumulation of liver extracellular matrix in thioacetamide (TAA) and carbon tetrachloride (CCl) induced mouse models for liver fibrosis. Furthermore, we determined that NMN inhibited oxidation-mediated 15-PGDH degradation to promote prostaglandin E degradation and suppress HSC activation. In summary, our results propose that NMN supplementation is a new therapeutic approach for liver fibrosis prevention.
Topics: Animals; Dinoprostone; Hepatic Stellate Cells; Liver; Liver Cirrhosis; Mice; Nicotinamide Mononucleotide; Thioacetamide
PubMed: 33220424
DOI: 10.1016/j.freeradbiomed.2020.11.014 -
Nature Communications Jul 2023Oxidative stress plays a crucial role in the pathogenesis of hepatic encephalopathy (HE), but the mechanism remains unclear. GABAergic neurons in substantia nigra pars...
Oxidative stress plays a crucial role in the pathogenesis of hepatic encephalopathy (HE), but the mechanism remains unclear. GABAergic neurons in substantia nigra pars reticulata (SNr) contribute to the motor deficit of HE. The present study aims to investigate the effects of oxidative stress on HE in male mice. The results validate the existence of oxidative stress in both liver and SNr across two murine models of HE induced by thioacetamide (TAA) and bile duct ligation (BDL). Systemic mitochondria-targeted antioxidative drug mitoquinone (Mito-Q) rescues mitochondrial dysfunction and oxidative injury in SNr, so as to restore the locomotor impairment in TAA and BDL mice. Furthermore, the GAD2-expressing SNr population (SNr) is activated by HE. Both overexpression of mitochondrial uncoupling protein 2 (UCP2) targeted to SNr and SNr-targeted chemogenetic inhibition targeted to SNr rescue mitochondrial dysfunction in TAA-induced HE. These results define the key role of oxidative stress in the pathogenesis of HE.
Topics: Male; Animals; Mice; Hepatic Encephalopathy; Oxidative Stress; Antioxidants; Bile Ducts; Thioacetamide
PubMed: 37488119
DOI: 10.1038/s41467-023-40081-8 -
Cell Stem Cell Jul 2018The development of complex in vitro hepatic systems and artificial liver devices has been hampered by the lack of reliable sources for relevant cell types, such as...
The development of complex in vitro hepatic systems and artificial liver devices has been hampered by the lack of reliable sources for relevant cell types, such as hepatic stellate cells (HSCs). Here we report efficient differentiation of human pluripotent stem cells into HSC-like cells (iPSC-HSCs). iPSC-HSCs closely resemble primary human HSCs at the transcriptional, cellular, and functional levels and possess a gene expression profile intermediate between that of quiescent and activated HSCs. Functional analyses revealed that iPSC-HSCs accumulate retinyl esters in lipid droplets and are activated in response to mediators of wound healing, similar to their in vivo counterparts. When maintained as 3D spheroids with HepaRG hepatocytes, iPSC-HSCs exhibit a quiescent phenotype but mount a fibrogenic response and secrete pro-collagen in response to known stimuli and hepatocyte toxicity. Thus, this protocol provides a robust in vitro system for studying HSC development, modeling liver fibrosis, and drug toxicity screening.
Topics: Cell Differentiation; Cells, Cultured; Coculture Techniques; Female; Hepatic Stellate Cells; Humans; Infant, Newborn; Liver Cirrhosis; Male; Models, Biological; Pluripotent Stem Cells; Thioacetamide; Wound Healing
PubMed: 30049452
DOI: 10.1016/j.stem.2018.05.027 -
Nature Communications May 2020Due to their bacterial ancestry, many components of mitochondria share structural similarities with bacteria. Release of molecular danger signals from injured cell...
Due to their bacterial ancestry, many components of mitochondria share structural similarities with bacteria. Release of molecular danger signals from injured cell mitochondria (mitochondria-derived damage-associated molecular patterns, mito-DAMPs) triggers a potent inflammatory response, but their role in fibrosis is unknown. Using liver fibrosis resistant/susceptible mouse strain system, we demonstrate that mito-DAMPs released from injured hepatocyte mitochondria (with mtDNA as major active component) directly activate hepatic stellate cells, the fibrogenic cell in the liver, and drive liver scarring. The release of mito-DAMPs is controlled by efferocytosis of dying hepatocytes by phagocytic resident liver macrophages and infiltrating Gr-1(+) myeloid cells. Circulating mito-DAMPs are markedly increased in human patients with non-alcoholic steatohepatitis (NASH) and significant liver fibrosis. Our study identifies specific pathway driving liver fibrosis, with important diagnostic and therapeutic implications. Targeting mito-DAMP release from hepatocytes and/or modulating the phagocytic function of macrophages represents a promising antifibrotic strategy.
Topics: Adult; Aged; Aged, 80 and over; Alarmins; Animals; Apoptosis; Disease Models, Animal; Disease Progression; Female; Hepatic Stellate Cells; Hepatocytes; Humans; Liver; Liver Cirrhosis; Macrophages; Male; Mice; Middle Aged; Mitochondria; Non-alcoholic Fatty Liver Disease; Phagocytosis; Thioacetamide; Young Adult
PubMed: 32398673
DOI: 10.1038/s41467-020-16092-0 -
Calcified Tissue International Jun 2023Osteoporosis, an age-related metabolic bone disease, is mainly caused by an imbalance between osteoblast-mediated bone formation and osteoclast-mediated bone resorption....
Osteoporosis, an age-related metabolic bone disease, is mainly caused by an imbalance between osteoblast-mediated bone formation and osteoclast-mediated bone resorption. At present, there are many osteoporosis drugs that can promote bone formation or inhibit bone resorption. However, there were few therapeutic drugs that can simultaneously promote bone formation and inhibit bone resorption. Oridonin (ORI), a tetracyclic diterpenoid compound isolated from Rabdosia rubescens, has been proved to have anti-inflammatory, anti-tumor effects. However, little is known about the osteoprotective effect of oridonin. Thioacetamide (TAA) is a common organic compound with significant hepatotoxicity. Recent studies have found that there was a certain association between TAA and bone injury. In this work, we investigated the effect and mechanism of ORI on TAA-induced osteoclastogenesis and inhibition of osteoblast differentiation. The results showed that TAA could promote the osteoclastogenesis of RAW264.7 by promoting the MAPK/NF-κB pathway, and also promoted p65 nuclear translocation and activated intracellular ROS generation, and ORI can inhibit these effects to inhibit TAA-induced osteoclastogenesis. Moreover, ORI can also promote the osteogenic differentiation pathway and inhibit adipogenic differentiation of BMSCs to promote bone formation. In conclusion, our results revealed that ORI, as a potential therapeutic drug for osteoporosis, could protect against TAA-induced bone loss and TAA-inhibited bone formation.
Topics: Humans; Osteogenesis; NF-kappa B; Thioacetamide; Core Binding Factor Alpha 1 Subunit; Osteoclasts; Bone Resorption; Osteoporosis; Cell Differentiation; RANK Ligand
PubMed: 37032340
DOI: 10.1007/s00223-023-01080-5 -
Molecules (Basel, Switzerland) Feb 2022Infections due to Gram-negative bacteria are increasingly dangerous due to the spread of multi-drug resistant strains, emphasizing the urgent need for new antibiotics...
Infections due to Gram-negative bacteria are increasingly dangerous due to the spread of multi-drug resistant strains, emphasizing the urgent need for new antibiotics with alternative modes of action. We have previously identified a novel class of antibacterial agents, thioacetamide-triazoles, using an antifolate targeted screen and determined their mode of action which is dependent on activation by cysteine synthase A. Herein, we report a detailed examination of the anti- structure-activity relationship of the thioacetamide-triazoles. Analogs of the initial hit compounds were synthesized to study the contribution of the aryl, thioacetamide, and triazole sections. A clear structure-activity relationship was observed generating compounds with excellent inhibition values. Substitutions to the aryl ring were generally best tolerated, including the introduction of thiazole and pyridine heteroaryl systems. Substitutions to the central thioacetamide linker section were more nuanced; the introduction of a methyl branch to the thioacetamide linker substantially decreased antibacterial activity, but the isomeric propionamide and -benzamide systems retained activity. Changes to the triazole portion of the molecule dramatically decreased the antibacterial activity, further indicating that 1,2,3-triazole is critical for potency. From these studies, we have identified new lead compounds with desirable in-vitro ADME properties and in-vivo pharmacokinetic properties.
Topics: Anti-Bacterial Agents; Escherichia coli; Gram-Negative Bacteria; Microbial Sensitivity Tests; Molecular Structure; Structure-Activity Relationship; Thioacetamide; Triazoles
PubMed: 35268619
DOI: 10.3390/molecules27051518 -
Microbiology Spectrum Dec 2021Recently, probiotics have been widely used as an adjuvant therapy to cure, prevent, or improve certain diseases. However, no research has been carried out into the dose...
Recently, probiotics have been widely used as an adjuvant therapy to cure, prevent, or improve certain diseases. However, no research has been carried out into the dose of probiotics, especially the maximum dose. Therefore, the effective and safe dosage of probiotics needs to be studied. Recently, L. Yang, X. Bian, W. Wu, L. Lv, et al. (Microb Biotechnol 13:1860-1876, 2020, https://doi.org/10.1111/1751-7915.13629) discovered that Lactobacillus salivarius Li01 had a protective effect on thioacetamide-induced acute liver injury and hyperammonemia, and a fixed concentration (3 × 10 CFU/mL) of Li01 was applied in their study. However, the most effective treatment concentration of Li01 remains unknown. Therefore, four concentration gradients of Li01 suspension were prepared for groups of mice to have different levels of bacterial colonization by gavage. Then, acute liver injury and hyperammonemia were induced via thioacetamide administration. By observation and detection, an inverted U-shaped protective effect from Li01 existed in thioacetamide-induced acute liver injury and hyperammonemia. Of note, significant deterioration was confirmed within the group that was orally administered with an excessive concentration of Li01 suspension, and this was attributed to endotoxemia that resulted from compromised immunity, a damaged intestinal barrier, and bacterial translocation. This research investigated the relationship between the concentration of Lactobacillus salivarius Li01 and its impact on mice that had a thioacetamide-induced acute liver injury and hyperammonemia. These findings could provide new insights into the effective, proper, and safe use of probiotics.
Topics: Acute Disease; Animals; Disease Models, Animal; Dose-Response Relationship, Drug; Humans; Hyperammonemia; Ligilactobacillus salivarius; Liver Diseases; Male; Mice; Mice, Inbred C57BL; Probiotics; Thioacetamide
PubMed: 34937168
DOI: 10.1128/spectrum.01847-21 -
Stem Cell Reports Nov 2022The detailed understanding of fibrogenesis has been hampered by a lack of important functional quiescence characteristics and an in vitro model to recapitulate hepatic...
The detailed understanding of fibrogenesis has been hampered by a lack of important functional quiescence characteristics and an in vitro model to recapitulate hepatic stellate cell (HSC) activation. In our study, we establish robust endoderm- and mesoderm-sourced quiescent-like induced HSCs (iHSCs) derived from human pluripotent stem cells. Notably, iHSCs present features of mature HSCs, including accumulation of vitamin A in the lipid droplets and maintained quiescent features. In addition, iHSCs display a fibrogenic response and secrete collagen I in response to hepatoxicity caused by thioacetamide, acetaminophen, and hepatitis B and C virus infection. Antiviral therapy attenuated virally induced iHSC activation. Interestingly, endoderm- and mesoderm-derived iHSCs showed similar iHSC phenotypes. Therefore, we provide a novel and robust method to efficiently generate functional iHSCs from hESC and iPSC differentiation, which could be used as a model for hepatocyte toxicity prediction, anti-liver-fibrosis drug screening, and viral hepatitis-induced liver fibrosis.
Topics: Humans; Hepatic Stellate Cells; Liver Cirrhosis; Thioacetamide; Hepatocytes; Pluripotent Stem Cells
PubMed: 36270282
DOI: 10.1016/j.stemcr.2022.09.010 -
Toxicology and Applied Pharmacology Nov 2021To study the complex processes involved in liver injuries, researchers rely on animal investigations, using chemically or surgically induced liver injuries, to... (Comparative Study)
Comparative Study
To study the complex processes involved in liver injuries, researchers rely on animal investigations, using chemically or surgically induced liver injuries, to extrapolate findings and infer human health risks. However, this presents obvious challenges in performing a detailed comparison and validation between the highly controlled animal models and development of liver injuries in humans. Furthermore, it is not clear whether there are species-dependent and -independent molecular initiating events or processes that cause liver injury before they eventually lead to end-stage liver disease. Here, we present a side-by-side study of rats and guinea pigs using thioacetamide to examine the similarities between early molecular initiating events during an acute-phase liver injury. We exposed Sprague Dawley rats and Hartley guinea pigs to a single dose of 25 or 100 mg/kg thioacetamide and collected blood plasma for metabolomic analysis and liver tissue for RNA-sequencing. The subsequent toxicogenomic analysis identified consistent liver injury trends in both genomic and metabolomic data within 24 and 33 h after thioacetamide exposure in rats and guinea pigs, respectively. In particular, we found species similarities in the key injury phenotypes of inflammation and fibrogenesis in our gene module analysis for liver injury phenotypes. We identified expression of several common genes (e.g., SPP1, TNSF18, SERPINE1, CLDN4, TIMP1, CD44, and LGALS3), activation of injury-specific KEGG pathways, and alteration of plasma metabolites involved in amino acid and bile acid metabolism as some of the key molecular processes that changed early upon thioacetamide exposure and could play a major role in the initiation of acute liver injury.
Topics: Animals; Biomarkers; Chemical and Drug Induced Liver Injury; Disease Models, Animal; Gene Expression Profiling; Gene Regulatory Networks; Guinea Pigs; Liver; Male; Metabolome; Metabolomics; Rats, Sprague-Dawley; Species Specificity; Thioacetamide; Time Factors; Transcriptome; Rats
PubMed: 34492290
DOI: 10.1016/j.taap.2021.115713