scholarly journals Astaxanthin Prevents Diet-Induced NASH Progression by Shaping Intrahepatic Immunity

2021 ◽  
Vol 22 (20) ◽  
pp. 11037
Author(s):  
Ming Yang ◽  
Eric T. Kimchi ◽  
Kevin F. Staveley-O’Carroll ◽  
Guangfu Li
Keyword(s):  
Oxidative Stress ◽  
Liver Fibrosis ◽  
Proinflammatory Cytokines ◽  
Molecular Mechanisms ◽  
Therapeutic Agent ◽  
Stellate Cell ◽  
In Vitro Studies ◽  
Alcoholic Fatty Liver ◽  
Duct Ligation

Dietary change leads to a precipitous increase in non-alcoholic fatty liver disease (NAFLD) from simple steatosis to the advanced form of non-alcoholic steatohepatitis (NASH), affecting approximately 25% of the global population. Although significant efforts greatly advance progress in clarifying the pathogenesis of NAFLD and identifying therapeutic targets, no therapeutic agent has been approved. Astaxanthin (ASTN), a natural antioxidant product, exerts an anti-inflammation and anti-fibrotic effect in mice induced with carbon tetrachloride (CCl4) and bile duct ligation (BDL); thus, we proposed to further investigate the potential effect of ASTN on a diet-induced mouse NASH and liver fibrosis, as well as the underlying cellular and molecular mechanisms. By treating pre-development of NASH in mice induced with a choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD), we have demonstrated that oral administration ASTN preventively ameliorated NASH development and liver fibrosis by modulating the hepatic immune response, liver inflammation, and oxidative stress. Specifically, ASTN treatment led to the reduction in liver infiltration of monocyte-derived macrophages, hepatic stellate cell (HSC) activation, oxidative stress response, and hepatocyte death, accompanied by the decreased hepatic gene expression of proinflammatory cytokines such as TNF-α, TGF-β1, and IL-1β. In vitro studies also demonstrated that ASTN significantly inhibited the expression of proinflammatory cytokines and chemokine CCL2 in macrophages in response to lipopolysaccharide (LPS) stimulation. Overall, in vivo and in vitro studies suggest that ASTN functions as a promising therapeutic agent to suppress NASH and liver fibrosis via modulating intrahepatic immunity.

Targeting ER protein TXNDC5 in hepatic stellate cell mitigates liver fibrosis by repressing non-canonical TGFβ signalling

Gut ◽  
2021 ◽  
pp. gutjnl-2021-325065
Author(s):  
Chen-Ting Hung ◽  
Tung-Hung Su ◽  
Yen-Ting Chen ◽  
Yueh-Feng Wu ◽  
You-Tzung Chen ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Liver Fibrosis ◽  
Liver Injury ◽  
Transforming Growth Factor ◽  
Stellate Cell ◽  
Transforming Growth Factor Β1 ◽  
Duct Ligation ◽  
Extracellular Matrix Production ◽  
Matrix Production

Background and objectivesLiver fibrosis (LF) occurs following chronic liver injuries. Currently, there is no effective therapy for LF. Recently, we identified thioredoxin domain containing 5 (TXNDC5), an ER protein disulfide isomerase (PDI), as a critical mediator of cardiac and lung fibrosis. We aimed to determine if TXNDC5 also contributes to LF and its potential as a therapeutic target for LF.DesignHistological and transcriptome analyses on human cirrhotic livers were performed. Col1a1-GFPTg, Alb-Cre;Rosa26-tdTomato and Tie2-Cre/ERT2;Rosa26-tdTomato mice were used to determine the cell type(s) where TXNDC5 was induced following liver injury. In vitro investigations were conducted in human hepatic stellate cells (HSCs). Col1a2-Cre/ERT2;Txndc5fl/fl (Txndc5cKO) and Alb-Cre;Txndc5fl/fl (Txndc5Hep-cKO) mice were generated to delete TXNDC5 in HSCs and hepatocytes, respectively. Carbon tetrachloride treatment and bile duct ligation surgery were employed to induce liver injury/fibrosis in mice. The extent of LF was quantified using histological, imaging and biochemical analyses.ResultsTXNDC5 was upregulated markedly in human and mouse fibrotic livers, particularly in activated HSC at the fibrotic foci. TXNDC5 was induced by transforming growth factor β1 (TGFβ1) in HSCs and it was both required and sufficient for the activation, proliferation, survival and extracellular matrix production of HSC. Mechanistically, TGFβ1 induces TXNDC5 expression through increased ER stress and ATF6-mediated transcriptional regulation. In addition, TXNDC5 promotes LF by redox-dependent JNK and signal transducer and activator of transcription 3 activation in HSCs through its PDI activity, activating HSCs and making them resistant to apoptosis. HSC-specific deletion of Txndc5 reverted established LF in mice.ConclusionsER protein TXNDC5 promotes LF through redox-dependent HSC activation, proliferation and excessive extracellular matrix production. Targeting TXNDC5, therefore, could be a potential novel therapeutic strategy to ameliorate LF.

scholarly journals The miRFIB-Score: A Serological miRNA-Based Scoring Algorithm for the Diagnosis of Significant Liver Fibrosis

Cells ◽  
2019 ◽  
Vol 8 (9) ◽  
pp. 1003 ◽  
Author(s):  
Lambrecht ◽  
Verhulst ◽  
Reynaert ◽  
van Grunsven
Keyword(s):  
Liver Fibrosis ◽  
Stellate Cell ◽  
Early Stage ◽  
Liver Stiffness ◽  
Diagnostic Tools ◽  
Circulating Mirnas ◽  
Alcoholic Fatty Liver ◽  
Chronic Alcohol Abuse ◽  
Significant Liver Fibrosis

Background: The current diagnosis of early-stage liver fibrosis often relies on a serological or imaging-based evaluation of the stage of fibrosis, sometimes followed by an invasive liver biopsy procedure. Novel non-invasive experimental diagnostic tools are often based on markers of hepatocyte damage, or changes in liver stiffness and architecture, which are late-stage characteristics of fibrosis progression, making them unsuitable for the diagnosis of early-stage liver fibrosis. miRNAs control hepatic stellate cell (HSC) activation and are proposed as relevant diagnostic markers. Methods: We investigated the possibility of circulating miRNAs, which we found to be dysregulated upon HSC activation, to mark the presence of significant liver fibrosis (F ≥ 2) in patients with chronic alcohol abuse, chronic viral infection (HBV/HCV), and non-alcoholic fatty liver disease (NAFLD). Results: miRNA-profiling identified miRNA-451a, miRNA-142-5p, Let-7f-5p, and miRNA-378a-3p to be significantly dysregulated upon in vitro HSC activation, and to be highly enriched in their extracellular vesicles, suggesting their potential use as biomarkers. Analysis of the plasma of patients with significant liver fibrosis (F ≥ 2) and no or mild fibrosis (F = 0-1), using miRNA-122-5p and miRNA-29a-3p as positive control, found miRNA-451a, miRNA-142-5p, and Let-7f-5p, but not miRNA-378a-3p, able to distinguish between the two patient populations. Using logistic regression analysis, combining all five dysregulated circulating miRNAs, we created the miRFIB-score with a predictive value superior to the clinical scores Fibrosis-4 (Fib-4), aspartate aminotransferase/alanine aminotransferase (AST/ALT) ratio, and AST to platelet ratio index (APRI). The combination of the miRFIB-score with circulating PDGFRβ-levels further increased the predictive capacity for the diagnosis of significant liver fibrosis. Conclusions: The miRFIB- and miRFIBp-scores are accurate tools for the diagnosis of significant liver fibrosis in a heterogeneous patient population.

scholarly journals A Comprehensive Review of Natural Products against Liver Fibrosis: Flavonoids, Quinones, Lignans, Phenols, and Acids

2020 ◽  
Vol 2020 ◽  
pp. 1-19
Author(s):  
Xiaoqi Pan ◽  
Xiao Ma ◽  
Yinxiao Jiang ◽  
Jianxia Wen ◽  
Lian Yang ◽  
...  
Keyword(s):  
Natural Products ◽  
Liver Fibrosis ◽  
Molecular Mechanisms ◽  
Stellate Cell ◽  
Combined Application ◽  
Heavy Burden ◽  
Ecm Degradation

Liver fibrosis resulting from continuous long-term hepatic damage represents a heavy burden worldwide. Liver fibrosis is recognized as a complicated pathogenic mechanism with extracellular matrix (ECM) accumulation and hepatic stellate cell (HSC) activation. A series of drugs demonstrate significant antifibrotic activity in vitro and in vivo. No specific agents with ideally clinical efficacy for liver fibrosis treatment have been developed. In this review, we summarized the antifibrotic effects and molecular mechanisms of 29 kinds of common natural products. The mechanism of these compounds is correlated with anti-inflammatory, antiapoptotic, and antifibrotic activities. Moreover, parenchymal hepatic cell survival, HSC deactivation, and ECM degradation by interfering with multiple targets and signaling pathways are also involved in the antifibrotic effects of these compounds. However, there remain two bottlenecks for clinical breakthroughs. The low bioavailability of natural products should be improved, and the combined application of two or more compounds should be investigated for more prominent pharmacological effects. In summary, exploration on natural products against liver fibrosis is becoming increasingly extensive. Therefore, natural products are potential resources for the development of agents to treat liver fibrosis.

scholarly journals White Button Mushroom Extracts Modulate Hepatic Fibrosis Progression, Inflammation, and Oxidative Stress In Vitro and in LDLR-/- Mice

Foods ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1788
Author(s):  
Paloma Gallego ◽  
Amparo Luque-Sierra ◽  
Gonzalo Falcon ◽  
Pilar Carbonero ◽  
Lourdes Grande ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Liver Fibrosis ◽  
Mouse Model ◽  
Stellate Cell ◽  
Water Soluble ◽  
Receptor Protein ◽  
Inflammasome Activation ◽  
Fibrosis Progression ◽  
And Oxidative Stress

Liver fibrosis can be caused by non-alcoholic steatohepatitis (NASH), among other conditions. We performed a study to analyze the effects of a nontoxic, water-soluble extract of the edible mushroom Agaricus bisporus (AB) as a potential inhibitor of fibrosis progression in vitro using human hepatic stellate cell (LX2) cultures and in vivo in LDLR-/- mice. Treatment of LX2 cells with the AB extract reduced the levels of fibrotic and oxidative-related markers and increased the levels of GATA4 expression. In LDLR-/- mice with high-fat diet (HFD)-induced liver fibrosis and inflammation, the progression of fibrosis, oxidative stress, inflammation, and apoptosis were prevented by AB extract treatment. Moreover, in the mouse model, AB extract could exert an antiatherogenic effect. These data suggest that AB mushroom extract seems to exert protective effects by alleviating inflammation and oxidative stress during the progression of liver fibrosis, possibly due to a decrease in Toll-like receptor 4 (TLR4) expression and a reduction in Nod-like receptor protein 3 (NLRP3) inflammasome activation. In addition, we observed a potential atheroprotective effect in our mouse model.

scholarly journals Physalin B attenuates liver fibrosis via suppressing LAP2α-HDAC1 mediated deacetylation of GLI1 and hepatic stellate cell activation

2020 ◽  
Author(s):  
Xiaoyun Zhu ◽  
Shengtao Ye ◽  
Jie Li ◽  
Meihui Zhang ◽  
Yanqiu Zhang ◽  
...  
Keyword(s):  
Liver Fibrosis ◽  
Hedgehog Signaling ◽  
Cell Activation ◽  
Stellate Cell ◽  
Histone Deacetylase 1 ◽  
Duct Ligation ◽  
Oncogene Homologue ◽  
Important Therapeutic Target

Background and Purpose: Liver fibrosis is one of the leading causes of morbidity and mortality worldwide of which no acceptable therapy exists. Accumulating evidence supports that glioma-associated oncogene homologue 1(GLI1) is a potentially important therapeutic target for liver fibrosis. This study investigates the antifibrotic activities and potential mechanisms of Physalin B (PB), a natural Solanaceae compound. Experimental Approach: Mice subjected to CCl4 challenge and bile duct ligation were used to study the antifibrotic effects of PB in vivo. Mouse primary hepatic stellate cells (pHSCs) and human HSC line LX‐2 also served as an in vitro liver fibrosis model. Liver fibrogenic genes, GLI1 downstream genes were examined using western blot and real-time PCR analyses. GLI1 acetylation and LAP2α-HDAC1 interaction were analyzed by coimmunoprecipitation. Key Results: In animal models, PB administration attenuated hepatic histopathological injury, collagen accumulation, and reduced the expression of fibrogenic genes. PB dose‐dependently suppressed fibrotic marker expression in LX‐2 cells and mouse pHSCs. Mechanistic studies showed PB inhibited GLI activity in a non-canonical Hedgehog signaling. PB blocked lamina-associated polypeptide 2 α (LAP2α)/ histone deacetylase 1 (HDAC1) complex formation thereby inhibited HDAC1mediated GLI1 deacetylation. PB downregulated the acetylation and expression of GLI1, and subsequently inhibiting HSC activation. Conclusions and Implications: PB exerted potent antifibrotic effects in vitro and in vivo by disrupting the LAP2α/HDAC1 complex, increasing GLI1 acetylation and inactivating GLI1. This indicates that PB may be a potential therapeutic candidate for the treatment of liver fibrosis.

Loss of Gab1 adaptor protein in hepatocytes aggravates experimental liver fibrosis in mice

2015 ◽  
Vol 308 (7) ◽  
pp. G613-G624 ◽  
Author(s):  
Takashi Kizu ◽  
Yuichi Yoshida ◽  
Kunimaro Furuta ◽  
Satoshi Ogura ◽  
Mayumi Egawa ◽  
...  
Keyword(s):  
Liver Fibrosis ◽  
Tyrosine Kinases ◽  
Molecular Mechanisms ◽  
Adaptor Protein ◽  
Conditional Knockout ◽  
Hepatocyte Proliferation ◽  
Duct Ligation ◽  
Liver Fibrogenesis

Grb2-associated binder 1 (Gab1) adaptor protein amplifies signals downstream of a broad range of growth factors/receptor tyrosine kinases. Although these signals are implicated in liver fibrogenesis, the role of Gab1 remains unclear. To elucidate the role of Gab1, liver fibrosis was examined in hepatocyte-specific Gab1-conditional knockout (Gab1CKO) mice upon bile duct ligation (BDL). Gab1CKO mice developed exacerbated liver fibrosis with activation of hepatic myofibroblasts after BDL compared with control mice. The antifibrotic role of hepatocyte Gab1 was further confirmed by another well-established mouse model of liver fibrosis using chronic injections of carbon tetrachloride. After BDL, Gab1CKO mice also displayed exacerbated liver injury, decreased hepatocyte proliferation, and enhanced liver inflammation. Furthermore, cDNA microarray analysis was used to investigate the potential molecular mechanisms of the Gab1-mediated signal in liver fibrosis, and the fibrosis-promoting factor chemokine (C-C motif) ligand 5 ( Ccl5) was identified as upregulated in the livers of Gab1CKO mice following BDL. Interestingly, in vitro studies using primary hepatocytes isolated from control and Gab1CKO mice revealed that the loss of Gab1 resulted in increased hepatocyte CCL5 synthesis upon lipopolysaccharide stimulation. Finally, pharmacological antagonism of CCL5 reduced BDL-induced liver fibrosis in Gab1CKO mice. In conclusion, our results demonstrate that hepatocyte Gab1 is required for liver fibrosis and that hepatocyte CCL5 could be an important contributor to this process. Thus, we present a novel antifibrotic function of hepatocyte Gab1 in liver fibrogenesis.

scholarly journals Baicalin Ameliorates Experimental Liver Cholestasis in Mice by Modulation of Oxidative Stress, Inflammation, and NRF2 Transcription Factor

2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Kezhen Shen ◽  
Xiaowen Feng ◽  
Hao Pan ◽  
Feng Zhang ◽  
Haiyang Xie ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Gene Expression ◽  
Cell Death ◽  
Liver Fibrosis ◽  
Liver Injury ◽  
Cell Activation ◽  
Nuclear Translocation ◽  
Stellate Cell ◽  
Tissue Growth ◽  
Duct Ligation

Experimental cholestatic liver fibrosis was performed by bile duct ligation (BDL) in mice, and significant liver injury was observed in 15 days. Administration of baicalin in mice significantly ameliorates liver fibrosis. Experimental cholestatic liver fibrosis was associated with induced gene expression of fibrotic markers such as collagen I, fibronectin, alpha smooth muscle actin (SMA), and connective tissue growth factor (CTGF); increased inflammatory cytokines (TNFα, MIP1α, IL1β, and MIP2); increased oxidative stress and reactive oxygen species- (ROS-) inducing enzymes (NOX2 and iNOS); dysfunctional mitochondrial electron chain complexes; and apoptotic/necrotic cell death markers (DNA fragmentation, caspase 3 activity, and PARP activity). Baicalin administration on alternate day reduced fibrosis along with profibrotic gene expression, proinflammatory cytokines, oxidative stress, and cell death whereas improving the function of mitochondrial electron transport chain. We observed baicalin enhanced NRF2 activation by nuclear translocation and induced its target genes HO-1 and GCLM, thus enhancing antioxidant defense. Interplay of oxidative stress/inflammation and NRF2 were key players for baicalin-mediated protection. Stellate cell activation is crucial for initiation of fibrosis. Baicalin alleviated stellate cell activation and modulated TIMP1, SMA, collagen 1, and fibronectin in vitro. This study indicates that baicalin might be beneficial for reducing inflammation and fibrosis in liver injury models.

scholarly journals Therapeutic Effects and Molecular Mechanisms of Ginkgo Biloba Extract on Liver Fibrosis in Rats

2006 ◽  
Vol 34 (01) ◽  
pp. 99-114 ◽  
Author(s):  
Shi-Quan Liu ◽  
Jie-Ping Yu ◽  
Hong-Lei Chen ◽  
He-Sheng Luo ◽  
Shi-Ming Chen ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Liver Fibrosis ◽  
Ginkgo Biloba ◽  
Molecular Mechanisms ◽  
Transforming Growth Factor ◽  
Stellate Cell ◽  
Ginkgo Biloba Extract ◽  
Therapeutic Effects ◽  
Dependent Manner ◽  
Mobility Shift

Oxidative stress can be implicated as a cause of liver fibrosis. In this sense, Ginkgo Biloba Extract (EGB), an antioxidant, may be beneficial in restraining liver fibrosis. The aim of this study was to evaluate the effects of EGB on experimental liver fibrosis. Rat liver fibrosis was induced by intraperitoneal injection of carbon tetrachloride ( CCl 4) twice a week for 8 weeks. Three groups of rats received EGB (0.25, 0.5 and 1.0 g/kg, respectively) by stomach everyday. CCl 4 administration induced liver fibrosis, which was inhibited by EGB in a dose-dependent manner. The histopathologic score of fibrosis, liver function and the levels of plasma hyaluronic acid (HA) and laminin (LN) were significantly improved in rats treated with CCl 4 + EGB , compared with those treated with CCl 4 only ( p < 0.01 or p < 0.05). The activities of superoxide dismutase (SOD) and glutathione pero xidase (GSH-Px) were notably elevated, while malondialdehyde (MDA) content was significantly decreased in the rats treated with CCl 4 + EGB ( p < 0.01 or p < 0.05). Inhibition of hepatic stellate cell (HSC) activation and nuclear factor kappaBP65 (NF-κBP65) expression was demonstrated in the livers of EGB-treated rats. The activation of NF-κB was significantly suppressed in EGB-treated rats determined by electrophoretic mobility shift assay (EMSA). Furthermore, EGB reduced expressions of transforming growth factor-β1 (TGF-β1) and collagen I mRNA. In conclusion, EGB is able to ameliorate liver injury and prevent rats from CCl 4-induced liver fibrosis by suppressing oxidative stress. This process may be related to inhibiting the induction of NF-κB on HSC activation and the expression of TGF-β1.

scholarly journals Sex differences in non-alcoholic fatty liver disease: hints for future management of the disease

2020 ◽  
Vol 1 (2) ◽  
pp. 51-74 ◽  
Author(s):  
Noel C. Salvoza ◽  
Pablo J. Giraudi ◽  
Claudio Tiribelli ◽  
Natalia Rosso
Keyword(s):  
Oxidative Stress ◽  
Sex Differences ◽  
Liver Disease ◽  
Fatty Liver ◽  
Fatty Liver Disease ◽  
Molecular Mechanisms ◽  
Protective Effects ◽  
Alcoholic Fatty Liver ◽  
Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) remains a major cause of chronic liver disease worldwide. Despite extensive studies, the heterogeneity of the risk factors as well as different disease mechanisms complicate the goals toward effective diagnosis and management. Recently, it has been shown that sex differences play a role in the prevalence and progression of NAFLD. In vitro, in vivo, and clinical studies revealed that the lower prevalence of NAFLD in premenopausal as compared to postmenopausal women and men is mainly due to the protective effects of estrogen and body fat distribution. It has been also described that males and females present differential pathogenic features in terms of biochemical profiles and histological characteristics. However, the exact molecular mechanisms for the gender differences that exist in the pathogenesis of NAFLD are still elusive. Lipogenesis, oxidative stress, and inflammation play a key role in the progression of NAFLD. For NAFLD, only a few studies characterized these mechanisms at the molecular level. Therefore, we aim to review the reported differential molecular mechanisms that trigger such different pathogenesis in both sexes. Differences in lipid metabolism, glucose homeostasis, oxidative stress, inflammation, and fibrosis were discussed based on the evidence reported in recent publications. In conclusion, with this review, we hope to provide a new perspective for the development of future practice guidelines as well as a new avenue for the management of the disease.

Targeting PPARalpha in Alzheimer's Disease

2018 ◽  
Vol 15 (4) ◽  
pp. 345-354 ◽  
Author(s):  
Barbara D'Orio ◽  
Anna Fracassi ◽  
Maria Paola Cerù ◽  
Sandra Moreno
Keyword(s):  
Oxidative Stress ◽  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Molecular Mechanisms ◽  
Redox Homeostasis ◽  
Antioxidant Response ◽  
Peroxisome Proliferator ◽  
Prevailing Paradigm

Background: The molecular mechanisms underlying Alzheimer's disease (AD) are yet to be fully elucidated. The so-called “amyloid cascade hypothesis” has long been the prevailing paradigm for causation of disease, and is today being revisited in relation to other pathogenic pathways, such as oxidative stress, neuroinflammation and energy dysmetabolism. The peroxisome proliferator-activated receptors (PPARs) are expressed in the central nervous system (CNS) and regulate many physiological processes, such as energy metabolism, neurotransmission, redox homeostasis, autophagy and cell cycle. Among the three isotypes (α, β/δ, γ), PPARγ role is the most extensively studied, while information on α and β/δ are still scanty. However, recent in vitro and in vivo evidence point to PPARα as a promising therapeutic target in AD. Conclusion: This review provides an update on this topic, focussing on the effects of natural or synthetic agonists in modulating pathogenetic mechanisms at AD onset and during its progression. Ligandactivated PPARα inihibits amyloidogenic pathway, Tau hyperphosphorylation and neuroinflammation. Concomitantly, the receptor elicits an enzymatic antioxidant response to oxidative stress, ameliorates glucose and lipid dysmetabolism, and stimulates autophagy.

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