Injection Of Carbon Tetrachloride Research Articles

Multiscale X-ray phase-contrast CT uncovers adaptive changes and compensatory mechanisms of circulatory pathways during acute liver injury

Intrahepatic circulation is essential for the repair of acute liver injury (ALI); however, very limited information is available concerning changes in the circulatory pathways during ALI. Therefore, multi-scale X-ray phase-contrast CT combined with three-dimensional (3D) visualization is used to quantitatively analyze the intrahepatic circulation pathway (including the hepatic vein, portal vein and hepatic sinusoid) in the mouse model via the intraperitoneal injection of carbon tetrachloride (CCl4) from acute injury to recovery. The results demonstrate that the liver still preserves some vessel-like channels accessed to the central vein when the injury causes the severe collapse of the hepatic sinusoids that cannot be observed in two-dimensional pathologic slices. Moreover, angiogenesis is observed in the terminal branches of the hepatic vein and portal vein. Additionally, we extend the two-dimensional primary lobule to a 3D model and find that the sinusoids in zone III have the most severe injury. The sinusoids in different zones also show changes in parameters such as density and mean diameter during the ALI. In conclusion, phase-contrast CT can reveal the intact vascular system within the liver lobes, thus providing critical information for studying the mechanisms involved in the evolution of circulatory structures from damage to repair.

Decompensated MASH-Cirrhosis Model by Acute and Toxic Effects of Phenobarbital.

Metabolic dysfunction-associated Steatohepatitis (MASH), is a prominent cause for liver cirrhosis. MASH-cirrhosis is responsible for liver complications and there is no specific treatment. To develop new therapeutic approaches, animal models are needed. The aim of this study was to develop a fast animal model of MASH-cirrhosis in rats reflecting the human disease. Carbon tetrachloride (CCl4) injections in combination with a high-fat Western diet (WD) were used to induce MASH-cirrhosis. To accelerate liver injury, animals received phenobarbital (PB) in their drinking water using two different regimens. Rats developed advanced MASH-cirrhosis characterized by portal hypertension, blood biochemistry, hepatic ballooning, steatosis, inflammation and fibrosis. Importantly, rats receiving low-dose PB for the long term (LT) showed ascites after 6 weeks, whereas rats with high-dose short-term (ST) PB developed ascites after 8 weeks. ST- and LT-treated rats showed increased portal pressure (PP) and decreased mean arterial pressure (MAP). Of note, hepatocyte ballooning was only observed in the LT group. The LT administration of low-dose PB with CCl4 intoxication and WD represents a fast and reproducible rat model mimicking decompensated MASH-cirrhosis in humans. Thus, CCl4 + WD with LT low-dose phenobarbital treatment might be the preferred rat animal model for drug development in MASH-cirrhosis.

Cycloastragenol Suppresses Hepatic Stellate Cells Activation to Alleviate Liver Fibrosis Through the PI3K/Akt/mTOR Signaling Pathway and Autophagy

Liver fibrosis is a pathological process of various liver diseases, and a large number of studies have shown that liver fibrosis is reversible. Natural products are one of the important sources of drugs for treating liver fibrosis. The present study evaluated the protective effect of cycloastragenol (CAG) on liver fibrosis and the underlying mechanism. The mouse model of liver fibrosis was established by intraperitoneal injection of carbon tetrachloride (CCl4) and olive oil. Subsequently, CAG was administrated orally at different doses(2.5 mg/kg/d, 5 mg/kg/d, 10mg/kg/d), and the degree of liver fibrosis was assessed using hematoxylin-eosin, Van Gieson, and Sirius Red staining. Alanine aminotransferase, aspartate aminotransferase, hyaluronic acid, and hydroxyproline levels were detected using biochemical analyses. The mRNA and protein expression levels of α-SMA, LC3, P62, PI3K, Akt, and mTOR in the liver tissue were assessed by reverse-transcription polymerase chain reaction and western blot, respectively. The expression of fibrogenesis-related marker α-SMA in the liver tissue was assessed using immunofluorescence. As expected, CAG alleviated liver fibrosis and suppressed hepatic stellate cell activation. And then, CAG inhibited autophagy and activated the PI3K/Akt/mTOR signaling pathway. Thus, CAG attenuated CCI4-induced liver fibrosis in mice by inhibiting autophagy and by activating the PI3K/Akt/mTOR signaling pathway.

AHCCⓇ inhibited Hepatic Stellate Cells Activation by Regulation of Cytoglobin induction via TLR2-SAPK/JNK pathway and Collagen Production via TLR4-NFκB pathway.

[Introduction] Cirrhosis, which represents the end stage of liver fibrosis, remains a life-threatening condition without effective treatment. Therefore, prevention of the progression of liver fibrosis through lifestyle habits such as diet and exercise is crucial. The functional food AHCCⓇ has been reported to be effective in improving the pathophysiology of various liver diseases. In this study, the aim was to analyze the influence of AHCCⓇ on hepatic stellate cells, which are responsible for liver fibrosis. [Materials and Methods] Eight-week-old male C57BL6/j mice were induced liver fibrosis by intraperitoneal injection of carbon tetrachloride. Simultaneously, they were orally administered 3% AHCCⓇto investigate its impact on the progression of liver fibrosis. Using the human hepatic stellate cell line HHSteC, we analyzed the influence of AHCCⓇ on the expression of molecules related to hepatic stellate cell activation. [Results] The administration of AHCCⓇ resulted in reduced expression of collagen1a, alpha smooth muscle actin (αSMA), and Heat shock protein 47 in the liver. Furthermore, the expression of cytoglobin, a marker for quiescent hepatic stellate cells, was enhanced. In vitro study, it was confirmed that AHCCⓇ inhibited αSMA by induction of cytoglobin via upregulating the SAPK/JNK pathway through toll-like receptor (TLR) 2. In addition, AHCCⓇ suppressed collagen1a production by hepatic stellate cells through TLR4-NFκβ pathway. [Conclusion] AHCCⓇ was suggested to suppress hepatic fibrosis by inhibition of hepatic stellate cells activation. Daily intake of AHCCⓇ from mild fibrotic stages may have the potential to prevent the progression of liver fibrosis.

Naringenin ameliorates MASH fibrosis via regulating TAK1/MAPK/FoxO3a-mediated apoptosis in the activated hepatic stellate cells

This study aims to explore the regulating effect and mechanism of naringenin (NGN) on the hepatic stellate cells (HSCs) apoptosis and its preventive effects on MASH fibrosis. C57BL/6 mice were subjected to either high-fat diet (HFD) plus carbon tetrachloride (CCl4) injection (HFD + CCl4) for 8 weeks to induce a MASH fibrosis model or bile duct ligation (BDL) to establish a liver fibrosis model, NGN was administered by gavage. LX2 cells were stimulated by oleic acid (OA) and lipopolysaccharide (LPS) (OA + LPS) to study the effects of NGN on activated hepatic stellate cell (HSC). Additionally, LO2 cells stimulated with OA + LPS were used to assess the protective effects of NGN on lipotoxicity of hepatocytes. Our in vivo results showed that NGN administration effectively inhibited mouse liver fibrosis in both of the MASH model and BDL model. The in vitro results indicate that NGN directly inhibited HSCs activation and promoted apoptosis of the activated HSCs, while it suppressed the apoptosis of LO2 cells induced by OA + LPS. The underlying mechanisms were mainly elucidated through the reduction of TAK1 phosphorylation, leading to the downregulation of p-JNK and p-ERK expression. This in turn, inhibited the phosphorylation of FoxO3a and promoted the nuclear localization of FoxO3a. Consequently, this may enhance the transcription of apoptosis-related genes, resulting in the apoptosis of activated HSCs. In conclusion, NGN ameliorates MASH fibrosis by enhancing apoptosis of the activated HSCs. The inhibitory effects of NGN on the TAK1/MAPK/FoxO3a pathway were demonstrated as its preventive mechanisms against MASH fibrosis.

Identify liver fibrosis associated hub genes using integrated bioinformatics analysis

BackgroundCirrhosis is defined as diffuse liver fibrosis (LF) caused by various chronic liver diseases and characterized by excessive deposition of extracellular matrix in liver tissue. However, the molecular mechanism of cirrhosis has not been well understood. This study aimed to identify significant gene expression profiles that participate in cirrhosis pathogenesis using bioinformatics and to discover novel biomarkers. MethodsTwo LF datasets (GSE14323 and GSE139602), both consisted of cirrhosis patients and healthy individuals, were obtained from the Gene Expression Omnibus (GEO) database and used for further analysis. Firstly, differential expression analyses were conducted to discover overlapping differentially expressed genes (DEGs) using the limma package. Next, the clusterProfiler function was adopted to carry out the Gene Ontology (GO) and Kyoto Encyclopedia of Genes as well as Genomes (KEGG) enrichment analyses. Furthermore, protein-protein interaction (PPI) network of the DEGs was constructed in the STRING database. In addition, hub genes were extracted through the cytoHubba plug-in. To verify the results we observed from the bioinformatics analysis, mouse models were established by receiving Carbon tetrachloride (CCl4) injections or 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) diet. ResultsA total of 81 upregulated and 21 downregulated overlapping DEGs were identified in cirrhosis tissues compared to healthy controls. 9 hub genes included SPP1, SOX9, THBS2, LUM, LAMA2, PECAM1, VIM, COL1A2, and COL3A1 were identified by the PPI analysis from the 81 upregulated overlapping DEGs. RT-PCR of the fibrotic liver tissues from the mouse model showed that the mRNA levels of Spp1, Sox9, Col1a2 and Col3a1 were up-regulated in mice treated with CCl4, while Spp1, Thbs2, Lum, Pecam1, Vim, Col1a2, and Col3a1 were up-regulated in mice treated with DDC. Predictive analyses provided drug compounds that are associated with LF. ConclusionThe present study identified hub genes that were associated with the occurrence of LF may provide reference for future studies to better explore the pathogenesis of cirrhosis, and play a possible role for developing drugs for LF.

Spatial Transcriptomics Reveals the Transcriptomic Signatures in a Mouse Model of Pediatric Metabolic Dysfunction–Associated Steatohepatitis

Metabolic dysfunction-associated steatohepatitis (MASH) is considered the progressive form of metabolic dysfunction-associated steatotic liver disease (MASLD), which is the leading cause of chronic liver disease in children. However, the pathogenesis of pediatric MASH remains poorly understood due to the lack of animal models. In this study, we developed a mouse model of pediatric MASH and characterized the hepatic transcriptomic profile using spatial transcriptomics (ST) technology. C57BL/6J mice were fed a western diet (WD) along with weekly injections of carbon tetrachloride (CCl4) from 3 weeks old to 8 weeks old. After 5 weeks of feeding, WD+CCl4-treated mice showed significant liver injury without the development of insulin resistance. Histologically, WD+CCl4 induced key features of type 2 MASH, the most common type observed in children, characterized by liver steatosis, portal inflammation, and portal fibrosis. Through ST analysis of liver tissues, we identified that cluster 0 in the mouse from the WD+CCl4 group was enriched in pathways associated with lipid metabolism. Further investigation revealed that cytochrome p450 2E1 (CYP2E1) was the top marker gene of cluster 0, and its expression was increased in the periportal area of mice from the WD+CCl4 group. These findings suggest that our mouse model of pediatric MASH mirrors the histological features of human MASH, and the upregulation of CYP2E1 may be linked to the disease pathogenesis.

Protective Effects of Hepatocyte Stress Defenders, Nrf1 and Nrf2, against MASLD Progression.

Progression of metabolic dysfunction-associated steatites liver disease (MASLD) to steatohepatitis (MASH) is driven by stress-inducing lipids that promote liver inflammation and fibrosis, and MASH can lead to cirrhosis and hepatocellular carcinoma. Previously, we showed coordinated defenses regulated by transcription factors, nuclear factor erythroid 2-related factor-1 (Nrf1) and -2 (Nrf2), protect against hepatic lipid stress. Here, we investigated protective effects of hepatocyte Nrf1 and Nrf2 against MASH-linked liver fibrosis and tumorigenesis. Male and female mice with flox alleles for genes encoding Nrf1 (Nfe2l1), Nrf2 (Nfe2l2), or both were fed a MASH-inducing diet enriched with high fat, fructose, and cholesterol (HFFC) or a control diet for 24-52 weeks. During this period, hepatocyte Nrf1, Nrf2, or combined deficiency for ~7 days, ~7 weeks, and ~35 weeks was induced by administering mice hepatocyte-targeting adeno-associated virus (AAV) expressing Cre recombinase. The effects on MASH, markers of liver fibrosis and proliferation, and liver tumorigenesis were compared to control mice receiving AAV-expressing green fluorescent protein. Also, to assess the impact of Nrf1 and Nrf2 induction on liver fibrosis, HFFC diet-fed C57bl/6J mice received weekly injections of carbon tetrachloride, and from week 16 to 24, mice were treated with the Nrf2-activating drug bardoxolone, hepatocyte overexpression of human NRF1 (hNRF1), or both, and these groups were compared to control. Compared to the control diet, 24-week feeding with the HFFC diet increased bodyweight as well as liver weight, steatosis, and inflammation. It also increased hepatocyte proliferation and a marker of liver damage, p62. Hepatocyte Nrf1 and combined deficiency increased liver steatosis in control diet-fed but not HFFC diet-fed mice, and increased liver inflammation under both diet conditions. Hepatocyte Nrf1 deficiency also increased hepatocyte proliferation, whereas combined deficiency did not, and this also occurred for p62 level in control diet-fed conditions. In 52-week HFFC diet-fed mice, 35 weeks of hepatocyte Nrf1 deficiency, but not combined deficiency, resulted in more liver tumors in male mice, but not in female mice. In contrast, hepatocyte Nrf2 deficiency had no effect on any of these parameters. However, in the 15-week CCL4-exposed and 24-week HFFC diet-fed mice, Nrf2 induction with bardoxolone reduced liver steatosis, inflammation, fibrosis, and proliferation. Induction of hepatic Nrf1 activity with hNRF1 enhanced the effect of bardoxolone on steatosis and may have stimulated liver progenitor cells. Physiologic Nrf1 delays MASLD progression, Nrf2 induction alleviates MASH, and combined enhancement synergistically protects against steatosis and may facilitate liver repair.

Efficacy and mechanism of action of Yanxiao Di'naer formula for non-alcoholic steatohepatitis treatment based on metabolomics and RNA sequencing

Ethnopharmacological relevanceNonalcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease worldwide. Nonalcoholic steatohepatitis (NASH) is a crucial component of this disease spectrum. The Yanxiao Di'naer formula (YXDNE) is an Uyghur medical extract that has been used in folk medicine to treat hepatitis for a long time. However, the role and mechanism of action of YXDNE in NASH treatment remains unclear. ObjectiveThe objective of this study was to assess the effectiveness of YXDNE in treating NASH induced by injections of carbon tetrachloride combined with a high-fat high-cholesterol diet (HFHCD), and to clarify the underlying mechanisms. MethodsThe compounds in the YXDNE extract were analysed for classification and proportions using ultra-performance liquid chromatography-mass spectrometry. The efficacy of YXDNE in treating abnormal lipid metabolism was evaluated in L02 cells in vitro. In addition, a C57BL/6 mouse model of NASH was established to evaluate the therapeutic efficacy of YXDNE in vivo. Metabolomics and RNA sequencing were used to analyse the therapeutic effects of YXDNE on the liver. The corresponding signalling pathways were found to target AMPKα1, PPARα, and NF-κB. The efficacy of YXDNE was validated using inhibitors or silencing RNA (siRNA) against AMPKα1 and PPARα. ResultsThis study confirmed that YXDNE treatment ameliorated NASH in a murine model of this disease. Metabolomics analysis suggested that YXDNE efficacy was associated with fatty acid catabolism and AMPK signalling pathways. RNA sequencing results showed that YXDNE efficacy in treating NASH was highly correlated with the AMPK, PPARα and NF-κB pathways. Both in vitro and in vivo experimental data demonstrated that YXDNE affected the expression of p-AMPKα1, PPARα, p–NF–κB, IκB, and p-IκB. The efficacy of YXDNE in treating NASH in vitro was cancelled when AMPK was inhibited with Compound C or PPARα was modulated via siRNA. ConclusionsYXDNE may have a therapeutic effect on abnormal lipid metabolism in L02 cells and in a murine model of NASH by affecting the AMPKα1/PPARα/NF-κB signalling pathway. Therefore, YXDNE has the potential for clinical application in the prevention and treatment of NASH.

H3K18 lactylation accelerates liver fibrosis progression through facilitating SOX9 transcription

Liver fibrosis is a significant health concern globally due to its association with severe liver conditions like cirrhosis and liver cancer. Histone lactylation has been implicated in the progression of hepatic fibrosis, but its specific role in liver fibrosis, particularly regarding H3K18 lactylation, remained unclear. To investigate this, we established in vivo and in vitro models of liver fibrosis using carbon tetrachloride (CCl4) injection in rats and stimulation of hepatic stellate cells (HSCs) with TGF-β1, respectively. We found that histone lactylation, particularly H3K18 lactylation, was upregulated in both CCl4-induced rats and TGF-β1-activated HSCs, indicating its potential involvement in liver fibrosis. Further experiments revealed that lactate dehydrogenase A (LDHA) knockdown inhibited H3K18 lactylation and had a beneficial effect on liver fibrosis by suppressing HSC proliferation, migration, and extracellular matrix (ECM) deposition. This suggests that H3K18 lactylation promotes liver fibrosis progression. Chromatin immunoprecipitation (ChIP) and luciferase reporter assays demonstrated that H3K18 lactylation facilitated the transcription of SOX9, a transcription factor associated with fibrosis. Importantly, overexpression of SOX9 counteracted the effects of LDHA silencing on activated HSCs, indicating that SOX9 is downstream of H3K18 lactylation in promoting liver fibrosis. In summary, this study uncovers a novel mechanism by which H3K18 lactylation contributes to liver fibrosis by activating SOX9 transcription. This finding opens avenues for exploring new therapeutic strategies for hepatic fibrosis targeting histone lactylation pathways.

Therapeutic Targeting of PKM2 Ameliorates NASH Fibrosis Progression in a Macrophage-Specific and Liver-Specific Manner

Nonalcoholic steatohepatitis (NASH) may soon become the leading cause of end-stage liver disease worldwide with limited treatment options. Liver fibrosis, which is driven by chronic inflammation and hepatic stellate cell (HSC) activation, critically determines morbidity and mortality in patients with NASH. Pyruvate kinase M2 (PKM2) is involved in immune activation and inflammatory liver diseases; however, its role and therapeutic potential in NASH-related fibrosis remain largely unexplored. Bioinformatics screening and analysis of human and murine NASH livers indicated that PKM2 was upregulated in nonparenchymal cells (NPCs), especially macrophages, in the livers of patients with fibrotic NASH. Macrophage-specific PKM2 knockout (PKM2FL/FLLysM-Cre) significantly ameliorated hepatic inflammation and fibrosis severity in three distinct NASH models induced by a methionine- and choline-deficient (MCD) diet, a high-fat high-cholesterol (HFHC) diet, and a western diet plus weekly carbon tetrachloride injection (WD/CCl4). Single-cell transcriptomic analysis indicated that deletion of PKM2 in macrophages reduced profibrotic Ly6Chigh macrophage infiltration. Mechanistically, PKM2-dependent glycolysis promoted NLR family pyrin domain containing 3 (NLRP3) activation in proinflammatory macrophages, which induced HSC activation and fibrogenesis. A pharmacological PKM2 agonist efficiently attenuated the profibrotic crosstalk between macrophages and HSCs in vitro and in vivo. Translationally, ablation of PKM2 in NPCs by cholesterol-conjugated heteroduplex oligonucleotides, a novel oligonucleotide drug that preferentially accumulates in the liver, dose-dependently reversed NASH-related fibrosis without causing observable hepatotoxicity. The present study highlights the pivotal role of macrophage PKM2 in advancing NASH fibrogenesis. Thus, therapeutic modulation of PKM2 in a macrophage-specific or liver-specific manner may serve as a novel strategy to combat NASH-related fibrosis.

Gadolinium deposition in the liver and brain in a rat model with liver fibrosis after intravenous administration of gadoxetate disodium

ObjectivesTo investigate gadolinium deposition in the liver and brain in a rat model with liver fibrosis (LF) after intravenous administration of gadoxetate disodium (GD) and the histological effects of gadolinium deposition in the liver and brain. MethodsAdult male Sprague–Dawley rats were randomly assigned to one of the three groups: 1) LF group received intraperitoneal injection of carbon tetrachloride (CCl4) for 9 weeks alone; 2) LF&GD group received CCl4 and intravenous administration of GD (for 5 consecutive days); 3) GD group received olive oil and GD. Seven days after the final injection of GD, the deep cerebellar nuclei (DCN) and liver were excised to determine gadolinium concentrations via inductively coupled plasma mass spectrometry, and histologic staining was performed. Bonferroni's post-hoc test and Wilcoxon rank sum test were used to compare the differences between the three groups. ResultsThe concentrations of retained gadolinium in the liver in the LF&GD group (2.18 ± 0.44 μg/g) were significantly greater compared to the LF group (0.02 ± 0.01 μg/g, P < 0.001) and GD group (0.37 ± 0.11 μg/g, P < 0.001). Also, the concentrations of retained gadolinium in DCN were increased in the LF&GD group (0.13 ± 0.06 μg/g) compared to the LF group (0.01 ± 0.00 μg/g, P < 0.001) and GD group (0.06 ± 0.02 μg/g, P = 0.019). No histopathological alterations were detected in the liver and DCN between LF&GD group and LF group. ConclusionsLF aggravated gadolinium deposition in the liver and DCN after administration of GD. However, no significant acute histological alterations were observed due to gadolinium deposition.

Evaluation of Kidney Injury Using Arterial Spin Labeling and Blood Oxygen Level-Dependent MRI: An Experimental Study in Rats With Carbon Tetrachloride-Induced Liver Cirrhosis.

Serum creatinine (Scr) may be not suited to timely and accurately reflect kidney injury related to chronic liver disease. Currently, the ability of arterial spin labeling (ASL) and blood oxygen level-dependent (BOLD) sequences to evaluate renal blood flow (RBF) and blood oxygen in chronic liver disease remains to be verified. To investigate the value of ASL and BOLD imaging in evaluating hemodynamics and oxygenation changes during kidney injury in an animal model of chronic liver disease. Prospective. Chronic liver disease model was established by subcutaneous injection of carbon tetrachloride. Forty-three male Sprague-Dawley rats (8 weeks) were divided into a pathological group (0, 2, 4, 6, 8, 12 weeks, each group: N = 6) and a continuous-scanning group (N = 7). 3-T, ASL, BOLD, and T2W. Regions of interest in the cortex (CO), outer stripe of the outer medulla (OSOM), and inner stripe of the outer medulla (ISOM) are manually delineated. The RBF and T2* values at each time point (0, 2, 4, 6, 8, 12 weeks) are measured and compared. Hematoxylin-eosin score (HE Score, damage area scoring method), alpha-smooth muscle actin (α-SMA), hypoxia-inducible factor-1alpha (HIF-1α), peritubular capillar (PTC) density, Scr, and neutrophil gelatinase-associated lipocalin were harvested. Analysis of variance, Spearman correlation analysis, Kruskal-Wallis tests, and receiver operating characteristic analysis with the area under the curve (AUC). A P-value <0.05 was considered statistically significant. Renal RBF and T2* values of CO, OSOM, and ISOM were significantly different from baseline. Both RBF and T2* were significantly correlated with HE Score, α-SMA, HIF-1α, and PTC density (|r| = 0.406-0.853). RBF demonstrated superior diagnostic capability in identifying severe kidney injury in this model of chronic liver disease (AUC = 0.964). Imaging by ASL and BOLD may detect renal hemodynamics and oxygenation changes related to chronic liver disease early. 5 TECHNICAL EFFICACY: Stage 2.

Endothelial anthrax toxin receptor 2 plays a protective role in liver fibrosis.

Hepatocellular carcinoma is one of the leading cancers worldwide and is a potential consequence of fibrosis. Therefore, the identification of key cellular and molecular mechanisms involved in liver fibrosis is an important goal for the development of new strategies to control liver-related diseases. Here, single-cell RNA sequencing data (GSE136103 and GES181483) of clinical liver non-parenchymal cells were analyzed to identify cellular and molecular mechanisms of liver fibrosis. The proportion of endothelial subpopulations in cirrhotic livers was significantly higher than that in healthy livers. Gene ontology and gene set enrichment analysis of differentially expressed genes in the endothelial subgroups revealed that extracellular matrix (ECM)-related pathways were significantly enriched. Since anthrax toxin receptor 2 (ANTXR2) interacts with the ECM, the expression of ANTXR2 in the liver endothelium was analyzed. ANTXR2 expression in the liver endothelium of wild-type (WT) mice significantly decreased after a 4-time sequential injection of carbon tetrachloride (CCl4) to induce liver fibrosis. Next, conditional knockout mice selectively lacking Antxr2 in endothelial cells were generated. After endothelial-specific Antxr2 knockout mice were subjected to the CCl4 model, the degree of liver fibrosis in the knockout group was significantly more severe than that in the control group. In addition, ANTXR2 in human umbilical vein endothelial cells promoted matrix metalloproteinase 2 (MMP2) activation to degrade the ECM in vitro. Finally, endothelial-specific overexpression of Antxr2 alleviated the development of liver fibrosis following adeno-associated virus treatment. Collectively, these results suggested that endothelial ANTXR2 plays a protective role in liver fibrosis. This function of ANTXR2 may be achieved by promoting MMP2 activation to degrade the ECM.

The Chemoprevention of Arthrospira platensis against Diethyl nitrosamine induced Hepatocellular Carcinoma via Amelioration of Oxidative Stress in Mice

Considering that natural antioxidant products do not have any negative side effects; they are an important component in the treatment and prevention of cancer. The purpose of the research was to explore whether Arthrospira platensis (SP) has hepatoprotective characteristics against hepatocellular carcinoma (HCC) in mice under the experimental conditions. The research was carried out with a group of fifty male Balb/c mice, they were then divided into five unique groups. Following is a list of the groups: (I) Group1: the normal control group, (II) Group 2: Hepatocellular carcinoma (HCC) group that was induced by a single injection of Diethyl nitrosamine (DEN) at a dosage of 100 mg/kg intraperitoneally (I. P). This was followed by injections of carbon tetrachloride (CCl4) twice a week 0.5 mg/kg body weight intraperitonially for a total of 22 weeks, beginning 14 days after the initial injection. (III) Group 3: Oral administration of SP at a dose of 250 mg/kg was given to the HCC group. (IV) Group 4, an oral dosage of SP containing 500 mg/kg was given to the animals, whereas (V) Group 5, an oral dose of 250 mg/kg of SP was given and considered as treatment control. The data revealed that the treatment of spirulina resulted in a significant decrease in the activity of glutamate oxaloacetate transaminase (GOT) also known to be AST, glutamate pyruvate transaminase (GPT) also known to be ALT, gamma-glutamate transaminase, and malondialdehyde (MDA). In addition, there was a notable increase in the total protein level, as well as in the activity of superoxide dismutase (SOD) and catalase (CAT), which were both much higher than normal levels. Spirulina has been shown to exhibit chemoprotective qualities, which may be linked to its antioxidant activity and its capacity to reduce lipid peroxidation has been demonstrated in every single study that has been conducted. In addition to this, it has been shown that spirulina can enhance the levels of pro-inflammatory cytokines, which in turn can significantly reduce inflammation.

Effectiveness of human adipose tissue-derived mesenchymal stem cells expressing alpha-1 antitrypsin gene in liver fibrosis: a study in mice.

The present study examined the protective potential of human adipose tissue-derived mesenchymal stem cells (hASCs) modified to overexpress alpha-1 antitrypsin (AAT), in a mouse model of the liver fibrosis. For the treatment of end-stage liver diseases, cell therapy has emerged as a promising noninvasive alternative to liver transplantation. Mesenchymal stem cells (MSCs) are being evaluated due to their dual capabilities of promoting liver regeneration and modulating the pathogenic inflammation of the immune system. Liver fibrosis was induced in mice via the intraperitoneal injection of carbon tetrachloride (CCl4). MSCs were extracted from the human adipose tissue. After stemness confirmation, the cells were transduced with the lentiviruses containing the AAT gene, and then injected into the mice's tail vein. Fourteen days' post-transplantation, mice were sacrificed, and blood and tissue samples were collected for analysis. Important liver enzymes, including alanine transaminase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), albumin, and total bilirubin (TB), were measured. Histological studies were carried out using the hematoxylin and eosin (H&E), as well as Masson's trichrome (MT) staining. Compared to hASCs, treatment with AAT-hASCs resulted in greater reductions in ALT, AST, ALP, and TB, as well as normalized albumin levels. AAT-hASCs promoted enhanced liver regeneration histologically, likely attributable to anti-inflammatory and anti-proteolytic properties of AAT. These findings indicate AAT-engineered hASCs as a promising cell-gene therapy candidate for further study in liver cirrhosis models.

A Mouse Model of Non-Alcoholic Steatohepatitis and Hepatocellular Carcinoma Induced by Western Diet and Carbon Tetrachloride.

Non-alcoholic steatohepatitis (NASH) is a severe form of non-alcoholic fatty liver disease (NAFLD). Obesity is a known risk factor of NASH, which, in turn, increases the risk of developing cirrhosis (liver scarring) and hepatocellular carcinoma (HCC). In addition to being a potentially life-threatening condition, public health concerns surrounding NASH are amplified by the lack of FDA-approved treatments. Although various preclinical models reflecting both the histopathology and the pathophysiological progression of human NASH exist, most of these models are diet-based and require 6-13months for NASH symptom manifestation. Here, we describe a simple and rapid-progression model of NASH and NASH-driven HCC in mice. Mice received a western diet equivalent (WD; i.e., a high-fat, high-fructose, and high-cholesterol diet), high-sugar water (23.1g/L fructose and 18.9g/L glucose), and weekly intraperitoneal injections of carbon tetrachloride (CCl4) at a dose of 0.2μL/g of body weight. The resulting phenotype, consisting in liver fibrosis and HCC, appeared within 24weeks of diet/treatment initiation and presented similar histological and transcriptomic features as human NASH and NASH-driven HCC, thereby supporting the adequacy of this preclinical model for the development and evaluation of drugs that can prevent or reverse these diseases.

Unacylated ghrelin attenuates acute liver injury and hyperlipidemia via its anti-inflammatory and anti-oxidative activities.

Liver injury and hyperlipidemia are major issues that have drawn more and more attention in recent years. The present study aimed to investigate the effects of unacylated ghrelin (UAG) on acute liver injury and hyperlipidemia in mice. UAG was injected intraperitoneally once a day for three days. Three hours after the last administration, acute liver injury was induced by intraperitoneal injection of carbon tetrachloride (CCl4), and acute hyperlipidemia was induced by intraperitoneal injection of poloxamer 407, respectively. Twenty-four hours later, samples were collected for serum biochemistry analysis, histopathological examination, and Western blotting. In acute liver injury mice, UAG significantly decreased liver index, serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α), reduced malondialdehyde (MDA) concentration and increased superoxide dismutase(SOD) in liver tissue. NF-kappa B (NF-κB) protein expression in the liver was down-regulated. In acute hyperlipidemia mice, UAG significantly decreased serum total cholesterol (TC), triglyceride (TG), ALT, and AST, as well as hepatic TG levels. Meanwhile, hepatic MDA decreased and SOD increased significantly. Moreover, UAG improved the pathological damage in the liver induced by CCl4 and poloxamer 407, respectively. Intraperitoneal injection of UAG exhibited hepatoprotective and lipid-lowering effects on acute liver injury and hyperlipidemia, which is attributed to its anti-inflammatory and anti-oxidant activities.

Ablation of DGKα facilitates α-smooth muscle actin expression via the Smad and PKCδ signaling pathways during the acute phase of CCl4 -induced hepatic injury.

Expression of α-smooth muscle actin (αSMA) is constitutive in vascular smooth muscle cells, but is induced in nonmuscle cells such as hepatic stellate cells (HSCs). HSCs play important roles in both physiological homeostasis and pathological response. HSC activation is characterized by αSMA expression, which is regulated by the TGFβ-induced Smad pathway. Recently, protein kinase C (PKC) was identified to regulate αSMA expression. Diacylglycerol kinase (DGK) metabolizes a second-messenger DG, thereby controlling components of DG-mediated signaling, such as PKC. In the present study we aimed to investigate the putative role of DGKα in αSMA expression. Use of a cellular model indicated that the DGK inhibitor R59949 promotes αSMA expression and PKCδ phosphorylation. It also facilitates Smad2 phosphorylation after 30 min of TGFβ stimulation. Furthermore, immunocytochemical analysis revealed that DGK inhibitor pretreatment without TGFβ stimulation engenders αSMA expression in a granular pattern, whereas DGK inhibitor pretreatment plus TGFβ stimulation significantly induces αSMA incorporation in stress fibers. Through animal model experiments, we observed that DGKα-knockout mice exhibit increased expression of αSMA in the liver after 48 h of carbon tetrachloride injection, together with enhanced phosphorylation levels of Smad2 and PKCδ. Together, these findings suggest that DGKα negatively regulates αSMA expression by acting on the Smad and PKCδ signaling pathways, which differentially regulate stress fiber incorporation and protein expression of αSMA, respectively.

Evaluation of The Effects of Dexmedetomidine against Carbontetracloride-Induced Nephrotoxicity via Oxidative Stress and Apoptosis

Objective: The objective of this work is to investigate the histological and biochemical consequences of administering Dexmedetomidine (DEX), an alpha-2 adrenergic receptor agonist with notable sedative qualities as well as antioxidant and anti-inflammatory characteristics, in the context of Carbon tetrachloride (CCl4)-induced kidney injury. Materials and Methods: The experimental design involved the random allocation of 30 Sprague-Dawley rats into three distinct groups. The experimental group designated as Group 1 received a single intraperitoneal administration of 1ml of saline solution containing 0.09% NaCl. Group 2 received an intraperitoneal injection of carbon tetrachloride (CCl4) at a dosage of 2 milliliters per kilogram. Group 3, referred to as the CCl4+Dexmedetomidine group, received a solitary intraperitoneal (i.p.) dosage of 100 µg/kg dexmedetomidine one hour before the intraperitoneal administration of 2mL/kg CCl4. Results: Extensive necrosis and debris accumulation were observed in the tubules, particularly in the proximal tubules, within the CCl4-applied group. An elevation in malondialdehyde (MDA) concentrations and terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) positivity, along with a reduction in glutathione (GSH) levels, was found in the renal tissues of the CCl4 experimental group as compared to the control group. In contrast, the CCl4+DEX group exhibited a reduction in the quantity of necrotic tubular cells, levels of MDA, and TUNEL positive. Additionally, there was an elevation in GSH levels compared to the group treated with CCl4 alone. Conclusions: The administration of dexmedetomidine has been observed to potentially provide a protective effect against renal damage induced by CCl4. This phenomenon could potentially be linked to the modulation of tissue oxidative stress markers and the attenuation of apoptotic rate. The findings of our investigation provide evidence in favour of the utilization of dexmedetomidine as a promising therapeutic drug for mitigating renal injury.