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Reductive metabolism of carbon tetrachloride (CCl4) is thought to cause lipid peroxidation which results in hepatic injury. Heme oxygenase-1 (HO-1) (EC 1.14.99.3), the rate-limiting enzyme in heme catabolism, is known to be induced by oxidative stress and to confer protection against oxidative tissue injuries. In this study, we examined the role of HO-1 induction in a rat model of CCl4-induced acute liver injury. CCl4 treatment (1 mL/kg, intraperitoneally) produced severe hepatic injury in rats as revealed by significant increases in serum alanine transaminase (ALT) (EC 2.6.1.2) activity and hepatic malondialdehyde (MDA) content, severe liver cell injury, and increases in hepatic tumor necrosis factor-α (TNF-α) mRNA expression and DNA binding activity of nuclear factor-κB (NF-κB). Following CCl4 treatment, hepatic HO-1 expression was markedly increased both at transcriptional and protein levels in hepatocytes, especially around the central vein. HO-1 induction was mediated in part through a rapid increase in microsomal free heme concentration presumably derived from hepatic cytochrome P450. Inhibition of HO activity by tin-mesoporphyrin (Sn-MP), which resulted in a sustained increase in microsomal free heme concentration, exacerbated liver injury, as judged by the sustained increase in serum ALT activity, extensive hepatocytes injuries, a more pronounced expression of hepatic TNF-α mRNA and an enhanced NF-κB activation. These findings indicate that induction of HO-1 is an adaptive response to CCl4 treatment, and it may be critical in the recovery of hepatocytes from injury. Our findings also suggest that HO-1 induction may play an important role in conferring protection on hepatocytes from oxidative damage caused by free heme. [Copyright &y& Elsevier]

Gallium-67 (67Ga) has been used as tumor or inflammation-imaging agent in nuclear medicine for decades. Although many hypotheses concerning the mechanism of uptake of 67Ga into tumors and inflammation have been proposed, consensus has not been reached. If the mechanism of 67Ga uptake is clarified, we can improve the sensitivity of diagnostic imaging with 67Ga. We attempted to clarify the mechanism of 67Ga uptake by the liver of carbon tetrachloride (CCl4)-treated rats. First, we investigated whether or not transferrin (Tf) is involved in 67Ga uptake by the liver tissue of CCl4-treated rats. It is well known that Fe3+ can inhibit the binding of 67Ga to Tf. The administration of FeCl3 5 min before the injection of 67Ga slightly enhanced the uptake of 67Ga by the liver tissue of CCl4-treated rats. The entering of 67Ga into hepatocytes of CCl4-treated rats was similar to the uptake by the liver tissue. In addition, the administration of FeCl3 slightly increased the entering of 67Ga to hepatocytes. These results suggest that free 67Ga enters into hepatocytes from the liver of CCl4-treated rats. [Copyright &y& Elsevier]

Background/aims: Liver regeneration after partial hepatectomy is thought to be regulated by various molecules including the components of the plasminogen activator (PA)-plasmin system. We have examined the role of fibrinolytic factors, i.e., tissue-type plasminogen activator (tPA) and urokinase-type plasminogen activator (uPA), and their substrate, plasminogen, in the proliferation of hepatocytes in primary culture. Methods: Hepatocyte and nonparenchymal liver cells were isolated from Wistar strain rat by a method perfusing the liver with collagenase. DNA synthesis was assessed by measuring the incorporation of [3H]-thymidine into cellular DNA fraction. tPA, uPA and type-1 plasminogen activator inhibitor (PAI-1) gene expressions were measured by Northern blotting. PA activity was measured by fibrin/agarose plate method. Results: Cellular density-dependent DNA synthesis was observed in the primary cultured hepatocytes; DNA synthesis was lower at high cell density (1.0×105 cells/cm2) than that at low cell density (0.2×105 cells/cm2). DNA synthesis in the hepatocytes cultured at a low cell density was increased by co-culture with nonparenchymal liver cells. Under these growth-stimulated culture conditions, tPA and uPA mRNAs were induced and up-regulated. On the contrary, the PAI-1 mRNA level was decreased under these conditions, and total PA activity was augmented accordingly. The synthetic plasmin inhibitor tranexamic acid, a competitive inhibitor for the plasmin molecule, and PASI-535, a plasmin active center-directed inhibitor, both suppressed hepatocyte proliferation in a dose-dependent fashion. Anti-plasmin antibody also suppressed hepatocyte proliferation. Conclusions: The up-regulation of PA activity for ensuring plasmin activity should be an important mechanism in the proliferation of hepatocytes. [Copyright &y& Elsevier]

Tumor necrosis factor receptor knockout (TNFR KO) mice were used to examine the role of tumor necrosis factor-α (TNFα) signaling during acute hepatotoxicant exposure. Mice were exposed intraperitoneally (ip) to either vehicle, phosphate-buffered saline (PBS), or dimethylnitrosamine (DMN, 100 mg/kg) for 24 h. Histological evaluation showed that DMN-treated TNFR-2 KO mice had increased liver damage compared to wild type (WT), TNFR-1 KO, or TNFR double KO (DKO) mice. Also, 3 of 8 TNFR-2 KO mice died following DMN treatment, suggesting that hepatic TNFR-2 signaling produces protective responses that counteract TNFR-1-mediated damage. DMN-induced cellular infiltration was absent in TNFR-1-deficient mice, indicating that infiltrating cells do not exacerbate acute hepatotoxic events. In separate experiments, mice were exposed ip to either DMN (5.0 or 100 mg/kg), carbon tetrachloride (CCl4, 0.3 or 1.0 ml/kg), or corresponding PBS/corn oil controls for 6 or 24 h to compare the hepatic mRNA expression of cytokine- and apoptotic-associated genes. Following 24 h of DMN (100 mg/kg) or 6–24 h of CCl4 treatment, hepatic transcripts for TNFα, interferon (IFN)-γ, IL (interleukin)-1RI, and transforming growth factor (TGF)-βRII were induced. Hepatotoxicant-treated WT and TNFR DKO mice induced liver transcripts for the pro- and anti-apoptotic genes, Bax and Bcl-XL, respectively, indicating TNF-independent gene activation. The anti-apoptotic gene, Bfl-1, was highly expressed in CCl4-treated, TNFR-positive strains, but minimally expressed in TNFR DKO mice, suggesting that hepatic Bfl-1 is TNF-regulated. Taken together, these data show that acute hepatotoxicant exposure is followed by upregulation of liver cytokine, cytokine receptor, and apoptotic transcripts, and that TNFα regulates various aspects of liver inflammation and injury in a TNFR-specific fashion. [ABSTRACT FROM PUBLISHER]

• A new mechanism of carbon tetrachloride pyrolysis inside an argon bubble is proposed. • The chemical bubble yield increases proportionally with the increase of CCl 4 mole fraction. • CCl 4 pyrolysis enhanced the formation reactive chlorine species (RCS) and OH radicals. • The contribution of RCS and OH depends on acoustic intensity. • For 1.5 W/cm2 and %CCl 4 < 0.007, the amounts of RCS and OH radicals are similar. • For %CCl 4 > 0.007, the production of RCS becomes dominant. In spite of the great number of experimental works conducted on CCl 4 sono-degradation, several controversies are observed, these including the main species generated upon CCl 4 decomposition and the mechanism by which CCl 4 accelerated the sonolytic removal of nonvolatile contaminants. In this paper, a new mechanism of carbon tetrachloride pyrolysis inside an argon bubble is proposed. In this model, the effects of heat exchange, mass transport and the chemical reactions heat on the bubble dynamics are taken into account. This model was used to explain the formation of the different species created by the pyrolytic decomposition of CCl 4 inside the bubble at 355 kHz for various acoustic intensities (In = 0.7, 1 and 1.5 W/cm2), where the whole range of CCl 4 concentration in the bulk solution is covered (from 0 to 5.2 × 10−3 mol/L, at 20 °C). It has been found that the increase of CCl 4 mole fraction inside the bubble decreases its maximal temperature. However, the chemical bubble yield increases proportionally with the increase of CCl 4 mole fraction. It has been demonstrated that CCl 4 enhances the sonolytic degradation of nonvolatile contaminants through the formation of reactive chlorine species (RCS: CCl 3 , :CCl 2 and Cl and HOCl) coupled with an increase of OH radicals yield when sonolysis is performed in the presence of CCl 4. Besides, the contributing effect of OH radicals and HOCl is lower than that of the other RCS. For the acoustic intensity of 1.5 W/cm2 and CCl 4 mole fractions within the bubble lower than ~0.007 (CCl 4 concentration ≤10−4 mol/L in the bulk solution), the amounts of RCS and OH radicals are approximately in the same range. However, for higher CCl 4 mole fractions (>0.007), the production of RCS becomes dominant. On the other hand, for the acoustic intensity of 1 W/cm2, the yield of RCS is dominant whatever the initial mole fraction of CCl 4 inside the bubble. It was found that the decrease of the solution pH is due to HCl and HOCl formation inside the bubble, where hydrochloric acid is produced in important quantity compared to hypochlorous acid for both cases 1 and 1.5 W/cm2. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the phytochemical constituents of Pandanus amaryllifolius as well as to evaluate its ability to protect against acute hepatic damage caused by carbon tetrachloride (CCl 4) in rats. In animals pre-treated with P.amaryllifolius and intoxicated with CCl 4 , biochemical parameters such as aspartate aminotransferase (AST), alanine aminotransferase (ALT), glutathione (GSH), catalase (CAT) and malondialdehyde (MDA) were used to assess hepatic damages. Histopathological assessment was also done to evaluate the CCl 4 mediated hepatic injury in rats. P.amaryllifolius antioxidant activity was measured using free radical scavenging DPPH (1,1-diphenyl-2-picrylhydrazyl) method. The stable DPPH level was lowered by P. amaryllifolius extract. The value of the half-maximum inhibitory level (IC 50) was 46.8 μg/ml. Phytochemical screening of P. amaryllifolius extract showed the presence of tannins, alkaloids, saponins, terpenoids and flavonoids except pholabatannins and cardiac glycosides. The total phenolic content (TPC) was 35.99 ± 0.04 mg GAE/g and total flavonoid content (TFC) was 59.96 ± 0.013 mg CAE/g of extract. P.amaryllifolius pre-treated groups displayed significantly increased catalase antioxidant enzyme activity relative to the CCl 4 treated group (57–82%, P < 0.05). P.amaryllifolius was found to moderately reduce serum ALT and AST levels (4–34%, P < 0.05). The formation of MDA due to lipid peroxidation was greatly reduced (29–70%, P < 0.05) when compared to the CCl 4 treated group, while GSH was raised in a dosage dependent way (94–100%, P < 0.05). Reduced histological changes in the liver were clear evidence of P. amaryllifolius protective effect. According to the research findings, the antioxidant and free radical scavenging properties of P. amaryllifolius may be responsible for its hepatoprotective benefits. [ABSTRACT FROM AUTHOR]

Non-alcoholic fatty liver disease (NAFLD) is a silent pandemic associated with obesity and the metabolic syndrome, and also increases cardiovascular- and cirrhosis-related morbidity and mortality. A complete understanding of adaptive compensatory metabolic programmes that modulate non-alcoholic steatohepatitis (NASH) progression is lacking. Transcriptomic analysis of liver biopsies in patients with NASH revealed that NASH progression is associated with rewiring of metabolic pathways, including upregulation of de novo lipid/cholesterol synthesis and fatty acid remodelling. The modulation of these metabolic programmes was achieved by activating sterol regulatory element-binding protein (SREBP) transcriptional networks; however, it is still debated whether, in the context of NASH, activation of SREBPs acts as a pathogenic driver of lipotoxicity, or rather promotes the biosynthesis of protective lipids that buffer excessive lipid accumulation, preventing inflammation and fibrosis. To elucidate the pathophysiological role of SCAP/SREBP in NASH and wound-healing response, we used an Insig1 deficient (with hyper-efficient SREBPs) murine model challenged with a NASH-inducing diet. Despite enhanced lipid and cholesterol biosynthesis, Insig1 KO mice had similar systemic metabolism and insulin sensitivity to Het/WT littermates. Moreover, activating SREBPs resulted in remodelling the lipidome, decreased hepatocellular damage, and improved wound-healing responses. Our study provides actionable knowledge about the pathways and mechanisms involved in NAFLD pathogenesis, which may prove useful for developing new therapeutic strategies. Our results also suggest that the SCAP/SREBP/INSIG1 trio governs transcriptional programmes aimed at protecting the liver from lipotoxic insults in NASH. • Human NASH biopsies' transcriptomics analysis features metabolic pathway rewiring. • SCAP/SREBP/INSIG1 modulation promotes lipid/cholesterol synthesis/remodelling in NASH. • Loss of Insig1 promotes lipid remodelling, preventing hepatic lipotoxicity in NASH. • Loss of Insig1 improves liver damage and wound healing and restrains NASH progression. [ABSTRACT FROM AUTHOR]

Summary: The phenotype and function of liver dendritic cells (LDCs) are poorly understood. This Snapshot summarizes our current knowledge on LDCs in the healthy and injured liver, and their role in fibrosis progression and reversal. It also draws attention to various pitfalls in the current experimental design and conclusions based on available data. [Copyright &y& Elsevier]

3,3′-Diindolylmethane (DIM), a metabolic product of indole-3-carbinol extracted from cruciferous vegetables exhibits anti-inflammatory and anti-cancer properties. Earlier, the product has been demonstrated to possess anti-fibrotic properties; however, its protective effects on liver injury have not been clearly elucidated. In this study, we postulated the effects and molecular mechanisms of action of DIM on carbon tetrachloride (CCl4)-induced liver injury in mice. Acute liver injury was induced by a single intraperitoneal administration of CCl4 (1 ml/kg) into mice. DIM was injected via subcutaneous route for three days at various doses (2.5, 5 and 10 mg/kg) before CCl4 injection. Mice were sacrificed and serum was collected for quantification of serum transaminases. The liver was collected and weighed. Treatment with DIM significantly reduced serum transaminases levels (AST and ALT), tumor necrosis factor-α (TNF-α) and reactive oxygen species (ROS). CCl4- induced apoptosis was inhibited by DIM treatment by the reduction in the levels of cleaved caspase-3 and Bcl2 associated X protein (Bax). DIM treated mice significantly restored Cytochrome P450 2E1, nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) expression in CCl4 treated mice. In addition, DIM downregulated overexpression of hepatic nuclear factor kappa B (NF-κB) and inhibited CCl4 mediated apoptosis. Our results suggest that the protective effects of DIM against CCl4- induced liver injury are due to the inhibition of ROS, reduction of pro-inflammatory mediators and apoptosis. [ABSTRACT FROM AUTHOR]

Autophagy is a lysosomal-dependent degradation pathway in eukaryotic cells. Recent studies have reported that autophagy can facilitate the activation of hepatic stellate cells (HSCs) and fibrogenesis of the liver during long-term carbon tetrachloride (CCl 4 ) exposure. However, little is known about the role of autophagy in CCl 4 -induced acute hepatic failure (AHF). This study aimed to identify whether modulation of autophagy can affect CCl 4 -induced AHF and evaluate the upstream signaling pathways mediated by CCl 4 -induced autophagy in rats. The accumulation of specific punctate distribution of endogenous LC3-II, increased expression of LC3-II, Atg5, and Atg7 genes/proteins, and decreased expression of p62 gene were observed after acute liver injury was induced by CCl 4 in rats, indicating that CCl 4 resulted in a high level of autophagy. Moreover, loss of autophagic function by using chloroquine (CQ, an autophagic inhibitor) aggravated liver function, leading to increased expression of p21 (a cyclin-dependent kinase inhibitor) in CCl 4 -treated rats. Furthermore, the AMPK-mTORC1-ULK1 axis was found to serve a function in CCl 4 -induced autophagy. These results reveal that AMPK-mTORC1-ULK1 signaling-induced autophagy has a protective role in CCl 4 -induced hepatotoxicity by inhibiting the p21 pathway. This study suggests a useful strategy aimed at ameliorating CCl 4 -induced acute hepatotoxicity by autophagy., (©2021 The Japanese Society of Toxicologic Pathology.)

Recent findings have revealed that extracellular vesicles (EVs) are secreted from cells and circulate in the blood. EVs are classified as exosomes (40-100 nm), microvesicles (50-1,000 nm) or apoptotic bodies (500-2,000 nm). EVs contain mRNAs, microRNAs, and DNAs and have the ability to transfer them from cell to cell. Recently, especially in humans, the diagnostic accuracy of tumor cell type-specific EV-associated miRNAs as biomarkers has been found to be more than 90 %. In addition, microRNAs contained in EVs in blood are being identified as specific biomarkers of chemical-induced inflammation and organ damage. Therefore, microRNAs contained in the EVs released into the blood from tissues and organs in response to adverse events such as exposure to chemical substances and drugs are expected to be useful as novel biomarkers for toxicity assessment. In this study, C57BL/6 J male mice orally dosed with carbon tetrachloride (CCl4) were used as a hepatotoxicity animal model. Here, we report that not only the known hepatotoxicity biomarkers miR-122 and miR-192 but also 42 novel EV-associated biomarkers were upregulated in mice dosed with CCl4. Some of these novel biomarkers may be expected to be able to use for better understanding the mechanism of toxicity. These results suggest that our newly developed protocol using EV-associated miRNAs as a biomarker would accelerate the rapid evaluation of toxicity caused by chemical substances and/or drugs., Competing Interests: The authors declare no competing interests., (© 2020 The Authors.)

Sirtuin3 (SIRT3) plays an important role in maintaining normal mitochondrial function and alleviating oxidative stress. After carbon tetrachloride (CCl4) administration, the expression of SIRT3 decreased in the liver of mice, which indicated that the SIRT3 might play a crucial role during chemical‐induced acute hepatic injury. To verify the hypothesis, CCl 4 was given to induce acute hepatic injury in SIRT3 knockout (KO) mice and wild‐type (WT) mice. CCl 4‐induced liver injury was more severe in SIRT3 KO mice compared with the WT mice. In addition, the oxidative stress induced by CCl 4 was enhanced in the SIRT3 KO mice. Furthermore, the increased expression of dynamin‐related protein 1 was also aggravated in SIRT3 KO mice after CCl 4 administration. In conclusion, our study demonstrated that SIRT3 deficiency exacerbated CCl 4‐induced impairment of the liver in mice, and the mechanism might be related to enhanced oxidative stress. [ABSTRACT FROM AUTHOR]

Sirtuin3 (SIRT3) plays an important role in maintaining normal mitochondrial function and alleviating oxidative stress. After carbon tetrachloride (CCl 4 ) administration, the expression of SIRT3 decreased in the liver of mice, which indicated that the SIRT3 might play a crucial role during chemical-induced acute hepatic injury. To verify the hypothesis, CCl 4 was given to induce acute hepatic injury in SIRT3 knockout (KO) mice and wild-type (WT) mice. CCl 4 -induced liver injury was more severe in SIRT3 KO mice compared with the WT mice. In addition, the oxidative stress induced by CCl 4 was enhanced in the SIRT3 KO mice. Furthermore, the increased expression of dynamin-related protein 1 was also aggravated in SIRT3 KO mice after CCl 4 administration. In conclusion, our study demonstrated that SIRT3 deficiency exacerbated CCl 4 -induced impairment of the liver in mice, and the mechanism might be related to enhanced oxidative stress., (© 2018 Wiley Periodicals, Inc.)

Natural killer (NK) cells are known for their ability to kill activated hepatic stellate cells (HSCs), which has been confirmed both in patients and animal models. But the killing function is depressed in period of advanced liver injury. Salvia Miltiorrhiza (SM), a Chinese herbal medicine for invigorating blood circulation and eliminating stasis, is widely used to treat liver fibrosis in clinic. Nevertheless, the immunological mechanism remains unclearly. Here, we put forward the hypothesis that the anti-fibrotic effect of SM is concerned with boosting the activation of hepatic NK cells. Liver fibrosis was induced with carbon tetrachloride (CCl 4 ) and effects of SM on NK cells and HSC (JS-1 cell line, HSC) were investigated in vivo and in vitr o. Hepatic NK cells were isolated from C57BL/6 mice, and pre-incubated with SM before they were co-cultured with HSCs. We found that SM increased frequency of NK cells, enhanced activities of NKG2D and Nkp46 on NK cells and inhibited activation of HSCs in vivo and in vitro . SM could promote the activities of NK cells by increasing the expressions of NKG2D and IFN-γ before or after co-cultured with HSCs in vitro . Besides, SM could partially antagonize ASGM-1-induced NK cell depletion and enhance the cell activities to inhibit HSCs activation in vitro . Therefore, our work provided a new insight into the anti-fibrotic mechanism that SM could enhance the activities of NK cell to reduce liver fibrosis in vivo and in vitro .

The present work was conducted to evaluate the genotoxic effect of carbon tetrachloride (CCl 4 ) in mouse bone marrow and male germ cells. The safety and the modulating activity of sage (Salvia officinalis L.) essential oil (SEO) against the possible genotoxic effect of CCl 4 were also evaluated. A combination of in vivo mutagenic endpoints was included: micronucleus (MN), apoptosis using dual acridine orange/ethidium bromide (AO/EB) staining, comet assay, chromosomal aberrations (CAs), and sperm abnormalities. Histological examination of testis tissues was also studied. The extracted SEO was subjected to gas chromatography-mass spectrometry (GC-MS) for identifying its chemical constituents. Safety/genotoxicity of SEO was determined after two consecutive weeks (5 days/week) from oral treatment with different concentrations (0.1, 0.2, and 0.4 mL/kg). For assessing genotoxicity of CCl 4 , both acute (once) and subacute i.p. treatment for 2 weeks (3 days/week) with the concentrations 1.2 mL/kg (for acute) and 0.8 mL/kg (for subacute) were performed. For evaluating the protective role of SEO, simultaneous treatment with SEO plus CCl 4 was examined. In sperm abnormalities, mice were treated with the subject materials for five successive days and the samples were collected after 35 days from the beginning of treatment. Based on GC-MS findings, 22 components were identified in the chromatogram of SEO. The results demonstrated that the three concentrations of SEO were safe and non-genotoxic in all the tested endpoints. Negative results were also observed in bone marrow after acute and subacute treatment with CCl 4. In contrast, CCl 4 induced testicular DNA damage as evidenced by a significant increase of CAs in primary spermatocytes, sperm abnormalities, and histological distortion of testis. A remarkable reduction in these cells was observed in groups treated with SEO plus CCl 4 especially with the two higher concentrations of SEO. In conclusion, SEO is safe and non-genotoxic under the tested conditions and can modulate genetic damage and histological alteration induced by CCl 4 in the testes.

Background: This study was carried out to evaluate the antioxidant and hepatoprotective effects of Vaccinium arctostaphylos (V.a) methanolic extract on carbon tetrachloride (CCl4)-induced acute liver injury in Wistar rats., Methods: Total phenolic and total flavonoid contents as well as antioxidant activity of V.a were determined. Extracts of V.a at doses of 200 and 400 mg/kg were administered by oral gavage to rats once per day for 7 days and then were given an intraperitoneal injection of 1 mL/kg CCl4 (1:1 in olive oil) for 3 consecutive days. Serum biochemical markers of liver injury, oxidative markers, as well as hydroxyproline (HP) content and histopathology of liver were evaluated., Results: The obtained results showed that V.a had strong antioxidant activity. Treatment of rats with V.a blocked the CCl4-induced elevation of serum markers of liver function and enhanced albumin and total protein levels. The level of hepatic HP content was also reduced by the administration of V.a treatment. Histological examination of the liver section revealed that V.a prevented the occurrence of pathological changes in CCl4-treated rats., Conclusions: These findings suggested that V.a may be useful in the treatment and prevention of hepatic injury induced by CCl4.

Ciliary neurotrophic factor (CNTF) and CNTF analogs were reported to have hepatoprotective effect and ameliorate hepatic steatosis in db/db or high-fat-diet-fed mice. Because hepatic steatosis and injury are also commonly induced by hepatotoxin, the aim of the present study is to clarify whether CNTF could alleviate hepatic steatosis and injury induced by carbon tetrachloride (CCl 4 ). Unexpectedly, when combined with CCl 4 , CNTF aggravated hepatic steatosis and liver injury. The mechanism is associated with effects of CNTF that inhibited lipoprotein secretion and drastically impaired the ability of lipoproteins to act as transport vehicles for lipids from the liver to the circulation. While injected after CCl 4 cessation, CNTF could improve liver function. These data suggest that CNTF could be a potential hepatoprotective agent against CCl 4 -induced hepatic injury after the cessation of CCl 4 exposure. However, it is forbidden to combine recombinant mutant of human CNTF treatment with CCl 4 .

Fibrosis is the excessive accumulation of extracellular matrix components due to chronic injury, with collagens as predominant structural components. Liver fibrosis can progress to cirrhosis, which is characterized by a severe distortion of the delicate hepatic vascular architecture, the shunting of the blood supply away from hepatocytes and the resultant functional liver failure. Cirrhosis is associated with a highly increased morbidity and mortality and represents the major hard endpoint in clinical studies of chronic liver diseases. Moreover, cirrhosis is a strong cofactor of primary liver cancer. In vivo models are indispensable tools to study the cellular and molecular mechanisms of liver fibrosis and to develop specific antifibrotic therapies towards clinical translation. Here, we provide a detailed description of select optimized mouse models of liver fibrosis and state-of-the-art fibrosis readouts.

Background: Preventing liver damage that might lead to cirrhosis is very important in the early stages of injury to that organ. The role of mast cells (MCs) in liver injuries has been long debated, and vitamin E is a well-known antioxidant used to treat those injuries. This study aimed to determine the protective role of vitamin E on MCs in injury to the liver that is triggered by carbon tetrachloride (CCl4). There is a correlation between MC deposits and improvement in fibrosis tissues., Methods: To further examine this, 68 male Albino Wistar rats were divided randomly into five groups: the control group, the vitamin E group, the CCl4 group, the CCl4 + vitamin E group, and the vitamin E + CCl4 group. Malondialdehyde (MDA) analysis, MC counts, histopathological investigation, and statistical analyses were used to evaluate the findings., Results: The administration of CCl4 resulted in an increase in the accumulation of MCs, degenerative parenchyma cells, MDA level, steatosis and inflammation. Additionally, proliferation of the bile ducts in the portal area and porto-portal and porto-central fibrosis were observed in the CCl4 group. In contrast, in the vitamin E group and in the groups administered a combination of vitamin E and CCl4, vitamin E prevented these increases., Conclusion: It was concluded that the significant decrease in the MC counts, in the level of MDA and the number of degenerative cells, as well as a decrease in the steatosis and inflammation scores showed that vitamin E could prevent liver injuries by protecting the organ's histological architecture. Finally, the results indicate that vitamin E has positive effects on liver injuries., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Background & Aims: Vascular endothelial growth factor (VEGF)−induced angiogenesis is implicated in fibrogenesis and portal hypertension. However, the function of VEGF in fibrosis resolution has not been explored. Methods: We developed a cholecystojejunostomy procedure to reconstruct biliary flow after bile duct ligation in C57BL/6 mice to generate a model of fibrosis resolution. These mice were then given injections of VEGF-neutralizing (mcr84) or control antibodies, and other mice received an adenovirus that expressed mouse VEGF or a control vector. The procedure was also performed on macrophage fas-induced apoptosis mice, in which macrophages can be selectively depleted. Liver and blood samples were collected and analyzed in immunohistochemical, morphometric, vascular permeability, real-time polymerase chain reaction, and flow cytometry assays. Results: VEGF-neutralizing antibodies prevented development of fibrosis but also disrupted hepatic tissue repair and fibrosis resolution. During fibrosis resolution, VEGF inhibition impaired liver sinusoidal permeability, which was associated with reduced monocyte migration, adhesion, and infiltration of fibrotic liver. Scar-associated macrophages contributed to this process by producing the chemokine (C-X-C motif) ligand 9 (CXCL9) and matrix metalloproteinase 13. Resolution of fibrosis was impaired in macrophage fas-induced apoptosis mice but increased after overexpression of CXCL9. Conclusions: In a mouse model of liver fibrosis resolution, VEGF promoted fibrogenesis, but was also required for hepatic tissue repair and fibrosis resolution. We observed that VEGF regulates vascular permeability, monocyte infiltration, and scar-associated macrophages function. [Copyright &y& Elsevier]

Background & Aims: Splanchnic vascular hypocontractility with subsequent increased portal venous inflow leads to portal hypertension. Although the renin−angiotensin system contributes to fibrogenesis and increased hepatic resistance in patients with cirrhosis, little is known about its effects in the splanchnic vasculature, particularly those of the alternate system in which angiotensin (Ang) II is cleaved by the Ang-converting enzyme-2 (ACE2) to Ang-(1−7), which activates the G-protein−coupled Mas receptor (MasR). We investigated whether this system contributes to splanchnic vasodilatation and portal hypertension in cirrhosis. Methods: We measured levels of renin−angiotensin system messenger RNA and proteins in splanchnic vessels from patients and rats with cirrhosis. Production of Ang-(1–7) and splanchnic vascular reactivity to Ang-(1–7) was measured in perfused mesenteric vascular beds from rats after bile-duct ligation. Ang-(1–7) and MasR were blocked in rats with cirrhosis to examine splanchnic vascular hemodynamics and portal pressure response. Results: Levels of ACE2 and MasR were increased in splanchnic vessels from cirrhotic patients and rats compared with healthy controls. We also observed an ACE2-dependent increase in Ang-(1–7) production. Ang-(1–7) mediated splanchnic vascular hypocontractility in ex vivo splanchnic vessels from rats with cirrhosis (but not control rats) via MasR stimulation. Identical effects were observed in the splanchnic circulation in vivo. MasR blockade reduced portal pressure, indicating that activation of this receptor in splanchnic vasculature promotes portal inflow to contribute to development of portal hypertension. In addition, the splanchnic effects of MasR required nitric oxide. Interestingly, Ang-(1–7) also decreased hepatic resistance. Conclusions: In the splanchnic vessels of patients and rats with cirrhosis, increased levels of ACE2 appear to increase production of Ang-(1–7), which leads to activation of MasR and splanchnic vasodilatation in rats. This mechanism could cause vascular hypocontractility in patients with cirrhosis, and might be a therapeutic target for portal hypertension. [Copyright &y& Elsevier]

Introduction: CCN4, also termed WNT-inducible signaling pathway protein-1 (WISP-1), has important roles in inflammation and tissue injury. This study aimed to investigate the effect of CCN4 inhibition using monoclonal anti-CCN4 antibody (CCN4mAb) on the liver injury and fibrosis in a mouse model of liver fibrosis., Material and Methods: The mouse liver fibrosis model was induced by carbon tetrachloride (CCl4). Mice received vehicle (saline/olive oil) by subcutaneous injection, CCl4 by subcutaneous injection or CCl4 (subcutaneous) plus CCN4mAb by subcutaneous injection. The pro-inflammatory and pro-fibrotic factors were determined by Western blot. The biochemistry and histopathology, collagen deposition and nuclear factor (NF)-κB activity were also assessed., Results: Chronic CCl4 treatment caused liver injury and collagen accumulation. The expression levels of CCN4, pro-inflammatory and pro-fibrotic mediators as well as the activity of NF-κB were markedly increased. Treatment with CCN4mAb significantly inhibited CCl4-induced CCN4 expression, leading to attenuated CCl4-induced liver injury and the inflammatory response. CCN4 blockade also significantly reduced the formation of collagen in the liver and the expression of α-smooth muscle actin and transforming growth factor β1., Conclusions: CCN4 inhibition by CCN4mAb in vivo significantly attenuated the CCl4-induced liver injury and the progression of liver fibrosis. CCN4 may represent a novel therapeutic target for liver injury and fibrosis.

Acute hepatic injury causes high morbidity and mortality world-wide. Management of severe acute hepatic failure continues to be one of the most challenging problems in clinical medicine. In present study, carbon tetrachloride (CCl4) was used to induce acute liver damage in mice and the protective effects of ethanol extract of Portulaca Oleracea L. (PO) were examined. The aminotransferase activities were biochemical estimated and the liver damage was tested by morphological histological analysis and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. The role of PO on the activity of NF-κB was determined by luciferase reporter gene assay and immunohistochemistry. The level of p-p65 was tested by western blot. Our results showed that PO administration on mice would decrease the serum aminotransferase level and reduced the liver histological damage. We also found that nuclear translocation of p65 was enhanced in liver tissues of mice treated with PO compared with control animals. In addition, in cultured hepatic cells, PO increased the NF-κB luciferase reporter gene activity and upregulated the level of phosphorylation of p65, but had no effects on mice liver SOD activity and MDA level. Collectively, PO attenuated CCl4 induced mice liver damage by enhancement of NF-κB activity.

Background: Herbal medicines played a major role in the treatment of hepatic disorders, and a number of medicinal plants and their compounds were widely used for the treatment of these disorders, and oxidant stress injury was one of the mechanism of liver injury., Materials and Methods: Antioxidant activity of Nelumbo nucifera leaves (NU) extracts was assayed by the methods of scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzo-thiazoline-6-sulfonicacid) (ABTS) radical and ferric reducing antioxidant power (FRAP) in vitro. By intraperitoneal injection carbon tetrachloride (CCl4) to establish acute liver injury model in mice, the levels of Glutamic-pyruvic transaminase (GPT), glutamic-oxaloacetic transaminase (GOT), superoxide dismutase (SOD) and the content of and maleicdialdehyde (MDA) were detected to evaluate hepatoprotective effect of NU using corresponding test kit., Results: EtOAC (NUEA) and n-BuOH extracts (NUBU) of N. nucifera leaves had good scavenging DPPH and ABTS radical activity and ferric reducing antioxidant power in vitro. DPPH radical scavenging activity and ferric reducing antioxidant power of NUEA (IC50= 6.68±0.29 µg/mL, RACT50=1749.82±67.03 µmol/g) and NUBU (IC50= 4.61±0.01 µg/mL, RACT50=1995.27±135.71 µmol/g ) were higher than that of BHT (IC50=8.76±0.20 µg/mL, RACT50=1581.68±97.41 µmol/g) and Dangfeiliganning (IC50=28.06±0.17 µg/mL, RACT50=1028.55±3.28 µmol/g). ABTS radical scavenging activity of NUEA (IC50= 5.32±0.12 µg/mL) and NUBU (IC50= 8.16±0.27 µg/mL) were higher than that of Dangfeiliganning (IC50= 9.76±0.16 µg/mL). Thus, hepatoprotective effect of NUEA and NUBU was evaluated on CCl4-induced acute liver injury mice. The results showed that the levels of GOT and GPT in each treatment group significantly decreased (p<0.001 and p<0.01, p<0.05, respectively) except for the group of NUEA (130.8 mg/kg) (p>0.05). The contents of malondialdehyde (MDA) in liver in groups of NUEA (523 mg/kg), NUBU (840.5 and 420.5 mg/kg, repectively) had significant decrease (p<0.001 and p<0.05, respectively), and the level of SOD in liver for each treatment group could significantly decrease (p<0.001, p<0.05, respectively)., Conclusion: NUEA and NUBU had significantly hepatoprotective effect for Calcium tetrachloride CCl4-induced liver injury, which might be attributable to its antioxidant activity.

The effects of a fermentation filtrate of Ganoderma lucidum (FGL) on carbon tetrachloride (CCl(4))-induced hepatic fibrosis were investigated in rats. Male Sprague-Dawley rats were orally administered with FGL (20 or 100 mg/kg) for 33 days, and orally administered with CCl(4) (1.0 mL/kg; 2 mL/kg of 50% in corn oil) at 3-day intervals 1 h after FGL treatment. Body and liver weights, blood and histopathological findings in accordance with hydroxyproline concentrations were analyzed. Chronic exposure to CCl(4) reduced the body weight gain, but increased liver weights and fibrosis, resulting in 3.35-fold increase in hydroxyproline level. Although FGL did not significantly reduce the CCl(4)-induced body and liver weight changes, it attenuated the increases in the hepatic fibrosis and hydroxyproline contents. Taken together, it is suggested that FGL might prevent hepatic fibrosis, and that FGL or its ingredient could be a potential candidate for the prevention of chronic hepatic disorders.