Molecular mechanisms of liver injury and hepatocarcinogenesis: focusing on the role of stress-activated MAPK

LCZ696 attenuates sepsis-induced liver dysfunction in rats; the role of oxidative stress, apoptosis, and JNK1/2-P38 signaling pathways

AIM

Sepsis is a serious inflammatory response to infection with an annual incidence rate of >48 million cases and 11 million fatalities worldwide. Furthermore, sepsis remains the world's fifth-greatest cause of death. For the first time, the current study aims to evaluate the possible hepatoprotective benefits of LCZ696, a combination of an angiotensin receptor blocker (valsartan) and a neprilysin inhibitor prodrug (sacubitril), on cecal ligation and puncture (CLP)-induced sepsis in rats.

MAIN METHODS

CLP was employed to induce sepsis. Hepatic malondialdehyde (MDA), reduced glutathione (GSH), superoxide dismutase (SOD), interleukin-6 (IL-6), IL-1β, tumor necrosis factor-alpha (TNF-α), and caspase 3 were assessed using ELISA. Serum alanine transaminase (ALT) and aspartate transaminase (AST) were also measured. Western blot assay was used to determine the expression of JNK1/2 and P38 proteins. The histology of liver tissues was also examined.

KEY FINDINGS

CLP resulted in significant elevation of AST, ALT, MDA, IL-6, IL-1β, TNF-α, and caspase 3 levels, and up-regulation of p/t JNK1/2, and p/t P38 proteins, as compared to the sham group. However, level of GSH, and SOD activity were reduced in CLP group. LCZ696 significantly improved all the previously mentioned biochemical and histological abnormalities better than using valsartan alone.

SIGNIFICANCE

LCZ696 substantially ameliorated CLP-induced liver damage, compared to valsartan, by reducing proinflammatory mediators, inhibiting the JNK1/2 and P38 signaling pathway, and attenuating apoptosis.

Hepatoprotective effects of Niudali (Callerya speciosa) root aqueous extracts against tetrachloromethane-induced acute liver injury and inflammation

Niudali (Callerya speciosa) is commonly grown in southeastern regions of China and consumed as a food ingredient. Although Niudali root extracts showed various biological activities, the hepatoprotective effects of Niudali root phytochemicals are not fully studied. Herein, we prepared two Niudali root aqueous extracts, namely, c and Niudali polysaccharides-enriched extract (NPE), and identified an alkaloid, (hypaphorine) in NEW. The hepatoprotective effects of NWE, NPE, and hypaphorine were evaluated in an acute liver injury model induced by carbon tetrachloride (CCl4) in mice. Pathohistological examination and blood chemistry assays showed that treatment of NWE, NPE, and hypaphorine alleviated CCl4-induced liver damage by lowering the liver injury score (by 75.51%, 80.01%, and 41.22%) and serum aspartate and alanine transaminases level (by 63.24%, 85.22%, and 49.74% and by 78.73%, 80.08%, and 81.70%), respectively. NWE, NPE, and hypaphorine also reduced CCl4-induced hepatic oxidative stresses in the liver tissue by decreasing the levels of malondialdehyde (by 40.00%, 51.25%, and 28.75%) and reactive oxygen species (by 30.22%, 36.14%, and 33.54%) while increasing the levels of antioxidant enzymes including superoxide dismutase (by 21.36%, 21.64%, and 8.90%), catalase (by 22.13%, 33.33%, and 5.39%), and glutathione (by 84.87%, 90.65%, and 80.53%), respectively. Mechanistic assays showed that NWE, NPE, and hypaphorine alleviated liver damage by mediating inflammatory biomarkers (e.g., pro-inflammatory cytokines) via the signaling pathways of mitogen-activated protein kinases and nuclear factor-κB. Findings from our study extend the understanding of Niudali's hepatoprotective effects, which is useful for its development as a dietary intervention for liver inflammation.

Pathophysiology of diabetic hepatopathy and molecular mechanisms underlying the hepatoprotective effects of phytochemicals

Patients with diabetes are at risk for liver disorders including glycogen hepatopathy, non-alcoholic fatty liver disease, cirrhosis, and hepatic fibrosis. The pathophysiological mechanisms behind diabetic hepatopathy are complex, some of them include fatty acid accumulation, increased reactive oxygen species, increased advanced glycation end-products, hyperactivity of polyol pathways, increased apoptosis and necrosis, and promotion of fibrosis. A growing number of studies have shown that herbal extracts and their active phytochemicals have antihyperglycemic properties and beneficial effects on diabetic complications. The current review, for the first time, focused on herbal agents that showed beneficial effects on diabetic hepatopathy. For example, animal studies have shown that Moringa oleifera and Morus alba improve liver function in both type-1 and type-2 diabetes. Also, evidence from clinical trials suggests that Boswellia serrata, Juglans regia, Melissa officinalis, Portulaca oleracea, Silybum marianum, Talapotaka Churna, and Urtica dioica reduce serum liver enzymes in diabetic patients. The main active ingredient of these plants to protect the liver seems to be phenolic compounds such as niazirin, chlorogenic acid, resveratrol, etc. Mechanisms responsible for the hepatoprotective activity of herbal agents include improving glucose metabolism, restoring adipokines levels, antioxidant defense, and anti-inflammatory activity. Several signaling pathways are involved in hepatoprotective effects of herbal agents in diabetes, such as phosphoinositide 3-kinase, adenosine monophosphate-activated protein kinase, mitogen-activated protein kinase, and c-Jun NH2-terminal kinase.

The mitigative effect of lotus root (Nelumbo nucifera Gaertn) extract on acute alcoholism through activation of alcohol catabolic enzyme, reduction of oxidative stress, and protection of liver function

Objectives

Lotus root (Nelumbo nucifera Gaertn) is a common medicinal-food dual-use vegetable. In this study, the effects of lotus root extract on acute alcoholism were investigated.

Methods

The Walle-Hoch method was used to determine the ADH activity of lotus root extracts in vitro. Lotus root methanol extract were identified by UPLC-QTOF-MS/MS based metabolomics analysis. Then 109 active ingredients with achievable oral doses and drug-like properties were explored using the TCMSP platform. SwissTargetPrediction Database to predict lotus root treatment targets for acute alcoholismSTRING database (https://www.string-db.org/) was used to construct protein-protein interaction network graphs. Gene ontology (GO) functional, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of genes common to lotus root and alcoholism by Metascap database. Molecular docking simulations were performed using AutoDock 1.5.6 software. Animal experiments verified the relieving effect of lotus root extract on acute alcoholism after intervention.

Results

Results indicated the methanol extract of lotus root showed the highest activation rate of ethanol dehydrogenase in vitro (18.87%). The 433 compounds of lotus root methanol extract were identified by UPLC-QTOF-MS/MS based metabolomics analysis. Bioinformatics analysis indicate that there were 224 intersectioning targets between lotus root extract and acute alcoholism. KEGG enrichment analysised shows that lotus root extract may play a role in treating acute alcoholism by intervening with the neuroactive ligand-receptor interaction pathway. The protein-protein interaction network (PPI) analysis found that HSP90AA1, MAPK1 and STAT3 played a key role in lotus root extract-modulated PPI networks. Molecular docking showed that (7R, 8S)-dihydrodihydrodipine cypressol had the best binding ability with MAPK1. Experiments in mice indicate that lotus root extract improved the activity of liver alcohol dehydrogenase (ADH), acetaldehyde dehydrogenase (ALDH), catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX), increase glutathione (GSH) and reduce malondialdehyde (MDA) levels, decrease glutamate transaminase (AST), alanine transaminase (ALT) and alkaline phosphatase (AKP) in the serum of mice with acute alcoholism, and accelerate the metabolic rate of alcohol after drinking. This study reveals the mechanism of lotus root to alleviate acute alcoholism, which provides a basis for further research on functional foods using lotus root and offers new possibilities for the treatment of acute alcoholism.

Conclusions

The results of the current study showed that the methanolic extract of lotus root had the highest activation rate of ethanol dehydrogenase. Network pharmacology results suggest that lotus root extract may play a role in the treatment of alcoholism by regulating signaling pathways, such as neuroactive ligand-receptor interactions, as well as biological processes, such as regulation of secretion, regulation of ion transport, response to lipopolysaccharides, and response to alcohol. Animal experiments confirmed the therapeutic effect of lotus root on acute alcoholism mechanistically through activation of alcohol catabolic enzyme, reduction of oxidative stress and protection of liver function.

Chemical component and in vitro protective effects of Matricaria chamomilla (L.) against lipopolysaccharide insult

ETHNOPHARMACOLOGICAL RELEVANCE

Chamomile (Matricaria chamomilla L.) is a popular herbal tea for the treatment of hepatitis and cholecystitis in traditional Uygur medicines.

AIM OF THE STUDY

To investigate the anti-inflammatory activity and chemical composition of M. chamomilla, and clarify its molecular mechanism.

MATERIALS AND METHODS

M. chamomilla was extracted with 75% ethanol and then extracted with different solvents to obtain five fractions, namely petroleum ether fraction (EOPE), dichloromethane fraction (EOD), ethyl acetate fraction (EOEA), n-butanol fraction (EOB), and water fraction (EOW). Cytotoxicity and the effect on the nitric oxide (NO) production of RAW264.7 cells induced by LPS of the five fractions were screened, and the most active one (EOD) was selected for further investigations. The components of EOD were identified by LC-MS/MS analysis in combination with comparison of retention time and UV absorption with authentic compounds by HPLC. In addition, five most abundant compounds of EOD were isolation by column chromatography and semi-preparative HPLC and their structures were further confirmed by HRMS and NMR data analysis and comparison with data in literatures. Then the underlying anti-inflammatory mechanism of EOD were predicted through Network pharmacology using the identified compounds from EOD, and further verified by Western Blot and ELISA experiments.

RESULTS

EOD showed the most significant inhibition ratio against NO in RAW264.7 cells without toxicity among the tested five fractions. Thirty-seven compounds including flavonoid-O-glycoside, flavonoid aglycone, methylated flavonoid aglycone, phenolic acid, coumarin, sesquiterpene, and triterpene were identified from EOD by LC-MS/MS and comparison with authentic compounds. The five most abundant compounds in EOD were isolated and determined to be axillarin (26), tricin (30), chrysoeriol (31), centaureidin (33) and chrysosplenetin (35). IL-6, NF-κB, ERK1 and ERK2 cascade, TNF were the most important anti-inflammatory targets of EOD predicted by Network pharmacology. Western Blot and ELISA experiments revealed that EOD significantly decreased the protein expression levels of inflammatory factors (PGE₂, MCP-1, IL-6, TNF-α), iNOS, COX-2, NF-κB (p-P65 and p-IκBα), MAPKs (p-p38, p-ERK and p-JNK), and increased the protein expression levels of Nrf2, HO-1 and CYP2E1. In addition, EOD blocked the p65 protein into the nucleus and promoted the nuclear translocation of Nrf2 in RAW264.7 cells induced by LPS.

CONCLUSION

M. chamomilla exerted anti-inflammatory effect via NF-κB, MAPK and Nrf2/HO-1 pathways. It could be further applied as a safe anti-inflammatory agent from natural source.

HIV-1 Tat Protein-Mediated Inflammatory Response Inhibits the Erythroid Hematopoietic Support Function of Bone Marrow Mesenchymal Stem Cells

Although combination antiretroviral therapy is widely used to treat HIV-1 infection, anemia affects the health and quality of life in a large number of these patients. The proliferation and differentiation of bone marrow mesenchymal stem cells (BMSCs), as important support cells in the hematopoietic microenvironment, can be affected by HIV-1 Tat protein. In this study, we explored the mechanism underlying the effect of Tat protein on the hematopoietic support function of BMSCs in erythroid commitment. BMSCs were treated with Tat protein or transfected with Tat mRNA and cocultured with hematopoietic stem cells (HSCs) to detect the number of erythroid colony-forming units (CFUs) and the proportion of mature red blood cells from HSCs. Subsequently, the expression level of a series of erythroid hematopoietic support factors and inflammatory factors in BMSCs after Tat treatment were analyzed. Then, the activation effect of Tat on the mitogen-activated protein kinase/nuclear factor kappa-B (MAPK/NF-κB) pathway, which is an important inflammatory response signaling pathway, was evaluated. The results showed that the number of erythroid CFUs and the production of mature red blood cells supported by BMSCs treated with Tat protein were significantly reduced and the expression of a series of erythroid supporting factors of BMSCs were significantly decreased by Tat protein. Tat-treated BMSCs highly express a variety of inflammatory mediators. Moreover, the expression of P38, p-p38, ERK1/2, p-ERK1/2, JNK1/2, p-JNK1/2, NF-κB, and p-NF-κB was significantly upregulated by Tat protein. In conclusion, Tat protein induces the inflammatory response of BMSCs by activating the MAPK/NF-κB pathway to inhibit the erythroid hematopoietic support function of BMSCs.

Lycopene in Combination With Sorafenib Additively Inhibits Tumor Metastasis in Mice Xenografted With Lewis Lung Carcinoma Cells

Cancer metastasis is the leading cause of death in cancer patients. However, it is unclear whether lycopene can act as an adjuvant to increase the anti-metastatic activity of anticancer drugs. Here, we examined the anti-lung-metastatic effects and the mechanism of lycopene in combination with sorafenib in C57BL/6 mice xenografted with Lewis lung carcinoma (LLC) cells. The mice were divided into five groups: (1) tumor control; (2) lycopene (5 mg/kg); (3) sorafenib (30 mg/kg); (4) lycopene (2 mg/kg) + sorafenib (30 mg/kg); (5) lycopene (5 mg/kg) + sorafenib (30 mg/kg). The results showed that lycopene reduced the number of metastatic tumors in the lungs, which was further suppressed by the combined treatment with sorafenib. The activities of matrix metalloproteinase (MMP)-2 and−9 were further inhibited and TIMP-1 and−2, and NM23-H1, the MMPs negative modulators, were further activated in the combined treatment. Mechanistically, we found that lycopene and sorafenib could additively inhibit the mitogen-activated protein kinase (MAPK) pathways, as shown by the protein phosphorylation of ERK1/2, JNK1/2 and p38 were reduced additively. Overall, the present study demonstrates that lycopene in combination with sorafenib additively inhibits the lung metastasis of tumor, indicating lycopene has potential as an adjuvant for sorafenib in cancer treatment.

Transcriptome analysis method based on differential distribution evaluation

Identifying differential genes over conditions provides insights into the mechanisms of biological processes and disease progression. Here we present an approach, the Kullback-Leibler divergence-based differential distribution (klDD), which provides a flexible framework for quantifying changes in higher-order statistical information of genes including mean and variance/covariation. The method can well detect subtle differences in gene expression distributions in contrast to mean or variance shifts of the existing methods. In addition to effectively identifying informational genes in terms of differential distribution, klDD can be directly applied to cancer subtyping, single-cell clustering and disease early-warning detection, which were all validated by various benchmark datasets.

Role of Mitochondrial Cytochrome P450 2E1 in Healthy and Diseased Liver

Cytochrome P450 2E1 (CYP2E1) is pivotal in hepatotoxicity induced by alcohol abuse and different xenobiotics. In this setting, CYP2E1 generates reactive metabolites inducing oxidative stress, mitochondrial dysfunction and cell death. In addition, this enzyme appears to play a role in the progression of obesity-related fatty liver to nonalcoholic steatohepatitis. Indeed, increased CYP2E1 activity in nonalcoholic fatty liver disease (NAFLD) is deemed to induce reactive oxygen species overproduction, which in turn triggers oxidative stress, necroinflammation and fibrosis. In 1997, Avadhani’s group reported for the first time the presence of CYP2E1 in rat liver mitochondria, and subsequent investigations by other groups confirmed that mitochondrial CYP2E1 (mtCYP2E1) could be found in different experimental models. In this review, we first recall the main features of CYP2E1 including its role in the biotransformation of endogenous and exogenous molecules, the regulation of its expression and activity and its involvement in different liver diseases. Then, we present the current knowledge on the physiological role of mtCYP2E1, its contribution to xenobiotic biotransformation as well as the mechanism and regulation of CYP2E1 targeting to mitochondria. Finally, we discuss experimental investigations suggesting that mtCYP2E1 could have a role in alcohol-associated liver disease, xenobiotic-induced hepatotoxicity and NAFLD.

Pathological predictive factors for late recurrence of hepatocellular carcinoma in chronic liver disease

BACKGROUND & AIMS

Late recurrence of hepatocellular carcinoma (HCC) is regarded as de novo HCC from chronic hepatitis. This study investigated clinicopathological and molecular factors to develop a nomogram for predicting late HCC recurrence (>2 years after curative resection).

METHODS

The training and validation cohorts included HCC patients with a major aetiology of hepatitis B who underwent curative resection. Clinicopathological features including lobular and porto-periportal inflammatory activity, fibrosis and liver cell change were evaluated. Proteins encoded by genes related to late recurrence were identified using a reverse phase protein array of 95 non-tumourous liver tissues. Immunoexpression of phosphorylated signal transducer and activator of transcription 3 (pSTAT3), plasminogen activator inhibitor-1, phosphorylated extracellular signal-regulated kinase 1/2 (pERK1/2) and spleen tyrosine kinase (SYK) was measured.

RESULTS

Late recurrence occurred in 74/402 (18%) and 47/243 (19%) in the training and validation cohorts respectively. Cirrhosis, moderate/severe lobular inflammatory activity, and expression of pSTAT3, pERK1/2, and SYK proteins correlated to the gene signature of hepatocyte injury and regeneration were independently associated with late recurrence, with odds ratios (95% confidence intervals) of 2.0 (1.2-3.3), 21.1 (4.3-102.7) and 6.0 (2.1-17.7) respectively (P < .05 for all). A nomogram based on these variables (histological parameters and immunohistochemical marker combinations) showed high reliability in both the training and validation cohorts (Harrell's C index: 0.701 and 0.716; 95% confidence intervals: 0.64-0.76 and 0.64-0.79 respectively).

CONCLUSIONS

The combination of pSTAT3, pERK1/2 and SYK immunoexpression with high lobular inflammatory activity and cirrhosis (fibrosis) predicts late HCC recurrence.

The expression and clinical significance of TPM4 in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is known as the fifth most common cancer in the world for its poor prognosis. New diagnostic markers and treatments are urgent to discover. To evaluate the protein expression of Tropomyosin4 (TPM4) and investigate its prognostic value in HCC, we collected 110 patients with different degrees of HCC and 10 patients with normal hepatic tissues and performed immunohistochemistry. Western bot was used to evaluate the expression of TPM4 in three HCC cell lines (HepG2, Huh7, SMMC-7721) and normal liver cell line LO2, as well as 7 HCC tissues and 7 normal hepatic tissues. The results of TPM4 staining revealed that TPM4 expression in HCC was higher than that in normal hepatic tissues, which was positive in 51.8% (n=57) and negative in 48.2% (n=53) while in normal hepatic tissues positive staining was in 10% (n=1) and negative staining was in 90% (n=9) (P=0.011). And the expression of TPM4 was related to pT status, grade and stage (P<0.001, P=0.015 and P<0.001, respectively). Western blot results indicated that TPM4 was high expressed in HCC cell line and HCC tissues. In conclusion, we believe that TPM4 can be applied as a diagnostic and prognostic marker to assist the management of HCC.

Comprehensive analysis of transcriptomics and metabolomics to understand triptolide-induced liver injury in mice

Triptolide, a major active component of Triptergium wilfordii Hook. f, is used in the treatment of autoimmune disease. However, triptolide is associated with severe adverse reactions, especially hepatotoxicity, which limits its clinical application. To examine the underlying mechanism of triptolide-induced liver injury, a combination of dose- and time-dependent toxic effects, RNA-seq and metabolomics were employed. Triptolide-induced toxicity occurred in a dose- and time-dependent manners and was characterized by apoptosis and not necroptosis. Transcriptomics profiles of the dose-dependent response to triptolide suggested that PI3K/AKT, MAPK, TNFα and p53 signaling pathways were the vital steps in triptolide-induced hepatocyte apoptosis. Metabolomics further revealed that glycerophospholipid, fatty acid, leukotriene, purine and pyrimidine metabolism were the major metabolic alterations after triptolide exposure. Finally, acylcarnitines were identified as potential biomarkers for the early detection of triptolide-induced liver injury.

An adverse outcome pathway for immune-mediated and allergic hepatitis: a case study with the NSAID diclofenac

Many drugs have the potential to cause drug-induced liver injury (DILI); however, underlying mechanisms are diverse. The concept of adverse outcome pathways (AOPs) has become instrumental for risk assessment of drug class effects. We report AOPs specific for immune-mediated and drug hypersensitivity/allergic hepatitis by considering genomic, histo- and clinical pathology data of mice and dogs treated with diclofenac. The findings are relevant for other NSAIDs and drugs undergoing iminoquinone and quinone reactive metabolite formation. We define reactive metabolites catalyzed by CYP monooxygenase and myeloperoxidases of neutrophils and Kupffer cells as well as acyl glucuronides produced by uridine diphosphoglucuronosyl transferase as molecular initiating events (MIE). The reactive metabolites bind to proteins and act as neo-antigen and involve antigen-presenting cells to elicit B- and T-cell responses. Given the diverse immune systems between mice and dogs, six different key events (KEs) at the cellular and up to four KEs at the organ level are defined with mechanistic plausibility for the onset and progression of liver inflammation. With mice, cellular stress response, interferon gamma-, adipocytokine- and chemokine signaling provided a rationale for the AOP of immune-mediated hepatitis. With dogs, an erroneous programming of the innate and adaptive immune response resulted in mast cell activation; their infiltration into liver parenchyma and the shift to M2-polarized Kupffer cells signify allergic hepatitis and the occurrence of granulomas of the liver. Taken together, diclofenac induces divergent immune responses among two important preclinical animal species, and the injury pattern seen among clinical cases confirms the relevance of the developed AOP for immune-mediated hepatitis.

The Protective Effect of the Polysaccharide Precursor, D-Isofloridoside, from Laurencia undulata on Alcohol-Induced Hepatotoxicity in HepG2 Cells

Alcoholic liver disease (ALD) threatens human health, so it is imperative that we find ways to prevent or treat it. In recent years, the study of polysaccharides has shown that they have different kinds of bioactivities. Among them are many biological effects that have been attributed to polysaccharide precursors. D-Isofloridoside (DIF) is one of the polysaccharide precursors from the marine red alga Laurencia undulata. This study evaluated the effect of DIF on alcohol-induced oxidative stress in human hepatoma cells (HepG2). As a result, DIF attenuated alcohol-induced cytotoxicity, reduced the amount of intracellular reactive oxygen species (ROS), and effectively reduced alcohol-induced DNA damage in HepG2 cells. In addition, a western blot showed that, after DIF treatment, the expression levels of glutathione (GSH), superoxide dismutase (SOD), and B-cell lymphoma-2 (bcl-2) increased, while the expression levels of γ-glutamyl transferase (GGT), BCL2-associated X (bax), cleaved caspase-3, and mitogen-activated protein kinase (p38 and c-Jun N-terminal kinase) signal transduction proteins reduced. This showed that DIF may protect cells by reducing the amount of intracellular ROS and inhibiting intracellular oxidative stress and apoptotic processes. Finally, molecular docking demonstrated that DIF can bind to SOD, GGT, B-cell lymphoma-2, and bax proteins. These results indicated that DIF can protect HepG2 cells from alcohol-induced oxidative stress damage, making it an effective potential ingredient in functional foods.

Mechanistic study of interaction between IL-22 and HCV core protein in the development of hepatocellular carcinoma among liver transplant recipients

BACKGROUND

Hepatitis C virus (HCV) infects more than 170 million people worldwide that represents a major threat to global public health. Several viruses including HCV have developed mechanisms against the cellular responses essentially "hijacking" the antiviral responses generated against it. Interleukin 22 activated JAK-STAT pathways are responsible for several functions including liver regeneration, antiviral responses and cell cycle regulation.

OBJECTIVES

Present study aims to un-reveal the speculated role of HCV core protein in perturbing IL-22 mediated JAK-STAT pathway. Principally investigating through interaction with IL-22 and SOCS-3 proteins.

PATIENTS AND METHODOLOGY

Total 36 liver transplant patients were enrolled in the study. Out of which 24 were found HCV + ve. Immunohistochemistry (IHC) based qualitative expression analysis of IL-22, SOCS-3 and HCV core protein was carried out. Microscopy was performed for detection and visualization of immunostained liver tissues and biopsies.

RESULTS

Hepatic expression of IL-22, HCV core protein and SOCS-3 showed that SOCS-3 expression levels were considerably high compared to HCV core and IL-22 protein. IL-22's moderate to high expression was found in 70% of the liver transplant patient sample. Total 87% patients showed moderate to high SOCS-3 expression. However, the overall expression of HCV core was stronger in 87% of cirrhotic patients and 14% in HCC patients. Suggesting the presence of HCV core protein clearly impacted the IL-22 mediated cellular signaling (JAK-STAT pathway leading towards hepatocarcinogenesis.

CONCLUSION

HCV core and IL-22 and SOCS-3 molecules are found to be correlated statistically under this study. Concluded from this study that HCV core protein plays a potential role in diverging the hepatocytes from normal to carcinogenic. One cell signaling path cannot decide, the direct role of a single viral protein in developing viral induced hepatocarcinogenesis. Interpreting the complex network of cell signaling involved in HCC development is impractical to study under single study. That is why step by step unmasking the interactive role of few molecules under single study is the ideal way to resolve the impact of viral proteins on cell signaling. SOCS-3 is mediator for dysregulating IL-22 mediated liver regenerative pathway. Moreover, SOCS-3 and STAT-3 molecules are proposed to be a potential therapeutic target for managing HCC progression.

Smad Phospho-Isoforms for Hepatocellular Carcinoma Risk Assessment in Patients with Nonalcoholic Steatohepatitis

Nonalcoholic steatohepatitis (NASH)-related hepatocellular carcinoma (HCC) sometimes occurs in mildly fibrotic livers, while HCC incidence in NASH-related cirrhosis is lower than and less predictable than in hepatitis C virus (HCV)-related cirrhosis. Transforming growth factor (TGF)-β signaling in hepatocytic nuclei is implicated in fibrosis and carcinogenesis. TGF-βtype I receptor (TβRI) and c-Jun N-terminal kinase (JNK) differentially phosphorylate the mediator Smad3, resulting in 2 distinct phospho-isoforms: C-terminally phosphorylated Smad3 (pSmad3C) and linker-phosphorylated Smad3 (pSmad3L). In mature hepatocytes, oncogenic signaling via the JNK/pSmad3L pathway antagonizes signaling via the tumor-suppressive TβRI/pSmad3C pathway. We immunohistochemically examined domain-specific Smad3 phosphorylation in liver biopsy specimens from 30 NASH patients representing different fibrotic stages and 20 chronically infected hepatitis C patients as controls, correlating Smad3 phosphorylation with clinical course. HCC occurred during follow-up in 11 of 12 NASH patients with abundant pSmad3L and limited pSmad3C but in only 2 of 18 with limited pSmad3L. In contrast, HCC developed in 12 of 15 NASH patients with limited pSmad3C but only 1 of 15 with abundant pSmad3C. Two of fourteen NASH patients with mild fibrosis developed HCC, their hepatocytic nuclei showed abundant pSmad3L and limited pSmad3C. Five of sixteen patients with severe fibrosis did not develop HCC, their hepatocytic nuclei showed limited pSmad3L and abundant pSmad3C. Smad phospho-isoforms may represent important biomarkers predicting HCC in NASH and potential therapeutic targets for preventing NASH-related HCC.

Crosstalk between NLRP12 and JNK during Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC), a leading cause of cancer-related death, is initiated and promoted by chronic inflammation. Inflammatory mediators are transcriptionally regulated by several inflammatory signaling pathways, including nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK). cJun N-terminal kinase (JNK), a member of the MAPK family, plays a central role in HCC pathogenesis. Pathogen-associated molecular patterns (PAMPs) activate JNK and other MAPK upon recognition by toll-like receptors (TLRs). Apart from TLRs, PAMPs are sensed by several other pattern recognition receptors, including cytosolic NOD-like receptors (NLRs). In a recent study, we demonstrated that the NLR member NLRP12 plays a critical role in suppressing HCC via negative regulation of the JNK pathway. This article briefly reviews the crosstalk between NLRP12 and JNK that occurs during HCC.

Anti-inflammatory effect of Vaccinium oldhamii stems through inhibition of NF-κB and MAPK/ATF2 signaling activation in LPS-stimulated RAW264.7 cells

Background

Vaccinium oldhamii (V. oldhamii) has been reported to exert a variety of the pharmacological properties such as anti-oxidant activity, anti-cancer activity, and inhibitory activity of α-amylase and acetylcholinesterase. However, the anti-inflammatory activity of V. oldhamii has not been studied. In this study, we aimed to investigate anti-inflammatory activity of the stem extracts from V. oldhamii, and to elucidate the potential mechanisms in LPS-stimulated RAW264.7 cells.

Methods

Cell viability was evaluated by MTT assay. The determination of NO and PGE2 production was performed using Griess reagent and Prostaglandin E₂ ELISA Kit, respectively. The change of mRNA or protein level was evaluated by RT-PCR and Western blot.

Results

Among VOS, VOL and VOF, the inhibitory effect of NO and PGE₂ production induced by LPS was highest in VOS treatment. Thus, VOS was selected for the further study. VOS dose-dependently blocked LPS-induced NO and PGE₂ production by inhibiting iNOS and COX-2 expression, respectively. VOS inhibited the expression of pro-inflammatory cytokines such as IL-1β, IL-6 and TNF-α. In addition, VOS suppressed TRAP activity and attenuated the expression of the osteoclast-specific genes such as NFATc1, c-FOS, TRAP, MMP-9, cathepsin K, CA2, OSCAR and ATPv06d2. VOS inhibited LPS-induced NF-κB signaling activation through blocking IκB-α degradation and p65 nuclear accumulation. VOS inhibited MAPK signaling activation by attenuating the phosphorylation of ERK1/2, p38 and JNK. Furthermore, VOS inhibited ATF2 phosphorylation and blocked ATF2 nuclear accumulation.

Conclusions

These results indicate that VOS may exert anti-inflammatory activity by inhibiting NF-κB and MAPK/ATF2 signaling. From these findings, VOS has potential to be a candidate for the development of chemopreventive or therapeutic agents for the inflammatory diseases.

Preactivated and disaggregated shape-changed platelets protect kidney against from ischemia-reperfusion injury in rat through attenuating inflammation reaction

This study tested the hypothesis that preactivated and disaggregated shape-changed platelet (PreD-SCP) therapy significantly protected rat kidney from ischemia-reperfusion (IR) injury. Adult-male Sprague-Dawley rats (n = 24) were equally categorized into Groups 1 (sham-operated control [SC]), 2 (SC + PreD-SCP), 3 (IR only), and 4 (IR + PreD-SCP). By 72 hr after IR procedure, the circulatory levels of creatinine, blood urine nitrogen and inflammatory biomarkers (interleukin [IL]-6/tumor necrosis factor [TNF]-α), and ratio of urine protein to urine creatinine were significantly higher in Group 3 than in other groups and significantly higher in Group 4 than in Groups 1 and 2, but they showed no different between Groups 1 and 2 (all p < .001). The microscopic findings showed that the expressions of kidney injury score, cellular inflammation (MMP-9/CD14//F4/80), and fibrotic area were identical to the circulatory inflammation, whereas the integrity of podocyte components (ZO-1/synaptopodin/podocin) exhibited an opposite to circulatory inflammation among the four groups (all p < .0001). The protein expressions of inflammatory (TNF-α/IL-1ß/NF-κB/iNOS/TRAF6/MyD88/TLR-4), apoptotic/cell death (mitochondrial Bax/cleaved caspase-3/p-53), oxidized protein, mitogen-activated protein kinase family (p-38/p-JNK/p-c-JUN), and mitochondrial-damaged biomarkers displayed a similar pattern, whereas the antiapoptotic (Bcl-2/Bcl-XL) and integrity of mitochondrial biomarkers followed an opposite trend to circulatory inflammation among the four groups (all p < .001). PreD-SCP therapy effectively protected the kidney against IR injury.

MicroRNA profiling of mouse liver in response to DENV-1 infection by deep sequencing

BACKGROUND

Dengue caused by dengue virus (DENV) serotypes -1 to -4 is the most important mosquito-borne viral disease in the tropical and sub-tropical countries worldwide. Yet many of the pathophysiological mechanisms of host responses during DENV infection remain largely unknown and incompletely understood.

METHODS

Using a mouse model, the miRNA expressions in liver during DENV-1 infection was investigated using high throughput miRNA sequencing. The differential expressions of miRNAs were then validated by qPCR, followed by target genes prediction. The identified miRNA targets were subjected to gene ontology (GO) annotation and pathway enrichment analysis to elucidate the potential biological pathways and molecular mechanisms associated with DENV-1 infection.

RESULTS

A total of 224 and 372 miRNAs out of 433 known mouse miRNAs were detected in the livers of DENV-1-infected and uninfected mice, respectively; of these, 207 miRNAs were present in both libraries. The miR-148a-3p and miR-122-5p were the two most abundant miRNAs in both groups. Thirty-one miRNAs were found to have at least 2-fold change in upregulation or downregulation, in which seven miRNAs were upregulated and 24 miRNAs were downregulated in the DENV-1-infected mouse livers. The miR-1a-3p was found to be the most downregulated miRNA in the DENV-1-infected mouse livers, with a significant fold change of 0.10. To validate the miRNA sequencing result, the expression pattern of 12 miRNAs, which were highly differentially expressed or most abundant, were assessed by qPCR and nine of them correlated positively with the one observed in deep sequencing. In silico functional analysis revealed that the adaptive immune responses involving TGF-beta, MAPK, PI3K-Akt, Rap1, Wnt and Ras signalling pathways were modulated collectively by 23 highly differentially expressed miRNAs during DENV-1 infection.

CONCLUSION

This study provides the first insight into the global miRNA expressions of mouse livers in response to DENV-1 infection in vivo and the possible roles of miRNAs in modulating the adaptive immune responses during DENV-1 infection.

Biosafety evaluation of Janus Fe3O4-TiO2 nanoparticles in Sprague Dawley rats after intravenous injection

Introduction

Newly synthesized Janus-structured Fe₃O₄-TiO₂ nanoparticles (NPs) appear to be a promising candidate for the diagnosis and therapy of cancer. Although the toxicity of individual Fe₃O₄ or TiO₂ NPs has been studied extensively, the toxicity of Janus Fe₃O₄-TiO₂ NPs is not clear.

Methods

In this study, the biosafety of both Janus Fe₃O₄-TiO₂ NPs (20–25 nm) and the maternal material TiO₂ NPs (7–10 nm) were evaluated in Sprague Dawley rats after one intravenous injection into the tail vein. Healthy rats were randomly divided into one control group and six experimental groups. Thirty days after treatment, rats were killed, then blood and tissue samples were collected for hematological, biochemical, element-content, histopathological, and Western blot analysis.

Results

The results show that only a slight Ti element accumulation in the heart, spleen, and liver could be found in the Janus Fe₃O₄-TiO₂ NP groups (P>0.05 compared with control). However, significant Ti element accumulation in the spleen, lungs, and liver was found in the TiO₂ NP-treated rats. Both Fe₃O₄-TiO₂ NPs and TiO₂ NPs could induce certain histopathological abnormalities. Western blot analysis showed that both NPs could induce certain apoptotic or inflammatory-related molecular protein upregulation in rat livers. A certain degree of alterations in liver function and electrolyte and lipid parameters was also observed in rats treated with both materials. However, compared to Janus structure Fe₃O₄-TiO₂ NP-treated groups, TiO₂ NPs at 30 mg/kg showed more severe adverse effects.

Conclusion

Our results showed that under a low dose (5 mg/kg), both NP types had no significant toxicity in rats. Janus NPs certainly seem less toxic than TiO₂ NPs in rats at 30 mg/kg. To ensure safe use of these newly developed Janus NPs in cancer diagnosis and therapy, further animal studies are needed to evaluate long-term bioeffects.

HBx-induced S100A9 in NF-κB dependent manner promotes growth and metastasis of hepatocellular carcinoma cells

Hepatocellular carcinoma (HCC) is associated with hepatitis B virus (HBV) infection. Myeloid-specific S100 proteins (S100s), namely, S100A8, S100A9 and S100A12, have been recently recognized as newly discovered damage-associated molecular patterns (DAMPs) that are correlated with progression in pathogen of infectious diseases. However, whether S100s are regulated by HBV and involved in HBV-related hepatocarcinogenesis are still unclear. Here, we found that all expression levels of myeloid-specific S100s (S100A8, S100A9 and S10012) were elevated in serum and tissue samples from HCC patients. Expression of S100A9 but not S100A8 and S10012 were also higher in blood serum and tissue samples from HBV-positive HCC patients than that in HBV-negative HCC patients. High levels of intracellular and extracellular S100A9 were also confirmed in HepG2 cells expressing 1.3-fold HBV genome or HBV-encoded X protein (HBx) as well as in a stable HBV-producing cell line HepG2.2.15. HBx was shown to facilitate translocation of NF-κB from the cytoplasm to the nucleus, and NF-κB bound to the promoter of S100A9 to enhance its transcription. Silencing S100A9 expression partially blocked HBx-induced growth and metastasis of HepG2 cells both in vitro and in vivo. Further, serum S100A9 levels were found to correlate with TNM stage, extrahepatic metastasis status and HBV DNA load in HBV-related HCC and also had a better diagnostic value for identifying extrahepatic metastasis. Our these data demonstrate that S100A9 plays a pivotal role in HBx-induced growth and metastasis of HCC and may serve as a potential diagnostic marker for extrahepatic metastasis.

Wood-cultivated ginseng exerts anti-inflammatory effect in LPS-stimulated RAW264.7 cells

Ginseng (Panax ginseng) has been reported to exert an anti-inflammatory activity in a variety of inflammatory condition. However, inflammation-regulatory activity of wood-cultivated ginseng has not been thoroughly evaluated. In this study, we evaluated the anti-inflammatory effect of wood-cultivated ginseng (WCG) and elucidated the potential mechanisms in LPS-stimulated RAW264.7 cells. WCG-O dose-dependently suppressed NO and PGE₂ production in LPS-stimulated RAW264.7 cells. In addition, WCG-O attenuated LPS-mediated overexpression of iNOS and COX-2. In addition, WCG-O blocked the expression of TNF-α and IL-1β. WCG-O inhibited the activation of IκK-α/β, the phosphorylation of IκB-α, and degradation of IκB-α, which results in the inhibition of p65 nuclear accumulation and NF-κB activation. In addition, WCG-O suppressed the activation of ERK1/2, p38 and JNK, which results in the inhibition of ATF2 nuclear accumulation. These results indicate that WCG-O may exert anti-inflammatory activity by inhibiting NF-κB and MAPK signaling. From these findings, WCG-O has potential to be a candidate for the development of chemopreventive or therapeutic agents for the inflammatory diseases.

The pathogenesis of diclofenac induced immunoallergic hepatitis in a canine model of liver injury

Hypersensitivity to non-steroidal anti-inflammatory drugs is a common adverse drug reaction and may result in serious inflammatory reactions of the liver. To investigate mechanism of immunoallergic hepatitis beagle dogs were given 1 or 3 mg/kg/day (HD) oral diclofenac for 28 days. HD diclofenac treatment caused liver function test abnormalities, reduced haematocrit and haemoglobin but induced reticulocyte, WBC, platelet, neutrophil and eosinophil counts. Histopathology evidenced hepatic steatosis and glycogen depletion, apoptosis, acute lobular hepatitis, granulomas and mastocytosis. Whole genome scans revealed 663 significantly regulated genes of which 82, 47 and 25 code for stress, immune response and inflammation. Immunopathology confirmed strong induction of IgM, the complement factors C3&B, SAA, SERPING1 and others of the classical and alternate pathway. Alike, marked expression of CD205 and CD74 in Kupffer cells and lymphocytes facilitate antigen presentation and B-cell differentiation. The highly induced HIF1A and KLF6 protein expression in mast cells and macrophages sustain inflammation. Furthermore, immunogenomics discovered 24, 17, 6 and 11 significantly regulated marker genes to hallmark M1/M2 polarized macrophages, lymphocytic and granulocytic infiltrates; note, the latter was confirmed by CAE staining. Other highly regulated genes included alpha-2-macroglobulin, CRP, hepcidin, IL1R1, S100A8 and CCL20. Diclofenac treatment caused unprecedented induction of myeloperoxidase in macrophages and oxidative stress as shown by SOD1/SOD2 immunohistochemistry. Lastly, bioinformatics defined molecular circuits of inflammation and consisted of 161 regulated genes.

Altogether, the mechanism of diclofenac induced liver hypersensitivity reactions involved oxidative stress, macrophage polarization, mastocytosis, complement activation and an erroneous programming of the innate and adaptive immune system.

[Inhibitory effect of giganteaside D on hepatocellular carcinoma Hep 3b cells and the underlying mechanisms]

OBJECTIVE

To investigate the inhibitory effect of giganteaside D (GD) on hepatocellular carcinoma and its molecular mechanisms.

METHODS

The inhibitory effects of GD on Hep 3b cells were determined using MTT assay and colony formation assay. The morphological changes of Hep 3b cells after GD treatment were observed by electron microscopy, and the cell cycle changes was analyzed using flow cytometry. The cell apoptosis and mitochondrial potential collapse in the treated cells were tested with Hoechst staining assay and flow cytometry. The expression levels of Bcl-2, PARP and key proteins in MAPK pathway were detected using Western blotting.

RESULTS

GD showed a significant inhibitory effect on Hep 3b cells with an IC₅₀ value of 16.08 µmol/L at 72 h. Flow cytometric analysis demonstrated that the phases of cell cycle remained unchanged and a sub-G1 peak (from 3.3% to 33.6%) appeared as GD concentration increased. GD-induced apoptosis was further conformed by Hoechst staining assay, and flow cytometry showed increased mitochondrial potential collapse in the cells. Western blotting demonstrated the cleavage of PARP, decrease of Bcl-2 and p-Erk1/2 (Thr202/Tyr204), and activation of p-p38 (Thr180/Tyr182) and p-JNK (Thr183/Tyr185) in GD-treated cells.

CONCLUSIONS

GD has significant inhibitory effect against hepatocellular carcinoma cells in vitro by inducing apoptosis possibly in association with the MAPK signaling pathway.

[Inhibitory effect of giganteaside D on hepatocellular carcinoma Hep 3b cells and the underlying mechanisms]

OBJECTIVE

To investigate the inhibitory effect of giganteaside D (GD) on hepatocellular carcinoma and its molecular mechanisms.

METHODS

The inhibitory effects of GD on Hep 3b cells were determined using MTT assay and colony formation assay. The morphological changes of Hep 3b cells after GD treatment were observed by electron microscopy, and the cell cycle changes was analyzed using flow cytometry. The cell apoptosis and mitochondrial potential collapse in the treated cells were tested with Hoechst staining assay and flow cytometry. The expression levels of Bcl-2, PARP and key proteins in MAPK pathway were detected using Western blotting.

RESULTS

GD showed a significant inhibitory effect on Hep 3b cells with an IC50 value of 16.08 µmol/L at 72 h. Flow cytometric analysis demonstrated that the phases of cell cycle remained unchanged and a sub-G1 peak (from 3.3% to 33.6%) appeared as GD concentration increased. GD-induced apoptosis was further conformed by Hoechst staining assay, and flow cytometry showed increased mitochondrial potential collapse in the cells. Western blotting demonstrated the cleavage of PARP, decrease of Bcl-2 and p-Erk1/2 (Thr202/Tyr204), and activation of p-p38 (Thr180/Tyr182) and p-JNK (Thr183/Tyr185) in GD-treated cells.

CONCLUSIONS

GD has significant inhibitory effect against hepatocellular carcinoma cells in vitro by inducing apoptosis possibly in association with the MAPK signaling pathway.

Salidroside pretreatment attenuates apoptosis and autophagy during hepatic ischemia-reperfusion injury by inhibiting the mitogen-activated protein kinase pathway in mice

Ischemia–reperfusion injury (IRI) contributes to liver damage in many clinical situations, such as liver resection and liver transplantation. In the present study, we investigated the effects of the antioxidant, anti-inflammatory, and anticancer agent salidroside (Sal) on hepatic IRI in mice. The mice were randomly divided into six groups: normal control, Sham, Sal (20 mg/kg), IRI, IRI + Sal (10 mg/kg), and IRI + Sal (20 mg/kg). We measured liver enzymes, proinflammatory cytokines, TNF-α and interleukin-6, and apoptosis- and autophagy-related marker proteins at 2, 8, and 24 hours after reperfusion. Components of mitogen-activated protein kinase (MAPK) signaling, including P-38, jun N-terminal kinase (JNK), and extracellular signal-regulated kinase (ERK), were also measured using an MAPK activator anisomycin to deduce their roles in hepatic IRI. Our results show that Sal safely protects hepatocytes from IRI by reducing levels of liver enzymes in the serum. These findings were confirmed by histopathology. We concluded that Sal protects hepatocytes from IRI partly by inhibiting the activation of MAPK signaling, including the phosphorylation of P38, JNK, and ERK. This ameliorates inflammatory reactions, apoptosis, and autophagy in the mouse liver.

Anti-Inflammatory, Antiapoptotic and Proproliferative Effects of Vitis vinifera Seed Ethanolic Extract in the Liver of Streptozotocin-Nicotinamide-Induced Type 2 Diabetes in Male Rats

OBJECTIVES

Consumption of Vitis vinifera seed has been reported to ameliorate liver pathology in diabetes mellitus; however, the mechanisms underlying its effects remain unknown. In this study, the anti-inflammatory, anti-apoptotic and pro-proliferative effects of the ethanolic seed extract of V. vinifera (VVSEE) in the liver in cases of diabetes were identified.

METHODS

Adult male rats with streptozotocin-nicotinamide-induced diabetes were given 50, 100 or 200 mg/kg body weight VVSEE orally for 28 days. At the end of the treatment, body weights were determined, and the blood was collected for analyses of fasting blood glucose, insulin and liver enzyme levels. Following sacrifice, livers were harvested and their wet weights and glycogen contents were measured. Histologic appearances of the livers were observed under light microscopy, and the expression and distribution of inflammatory, apoptosis and proliferative markers in the livers were identified by molecular biologic techniques.

RESULTS

Treatment of rats with diabetes by VVSEE attenuates decreased body weight, liver weight and liver glycogen content. Additionally, increases in fasting blood glucose levels and liver enzyme levels and decreases in serum insulin levels were ameliorated. Lesser histopathologic changes were also observed: decreased inflammation and apoptosis, as indicated by decreased levels of inflammatory markers (TNF-α, NF-Kβ, IKK-β, IL-6, IL-1β) and apoptosis markers (caspase-3, caspase-9 and Bax). VVSEE treatment induces increase in hepatocyte regeneration, as indicated by increased PCNA and Ki-67 distribution in the livers of rats with diabetes. Several molecules identified in VVSEE via gas chromatography mass spectrometry might contribute to these effects.

CONCLUSIONS

The anti-inflammatory, anti-apoptotic and pro-proliferative effects of VVSEE could account for its hepatoprotective actions in diabetes.

Activation of hepatic stellate cells by the ubiquitin C-terminal hydrolase 1 protein secreted from hepatitis C virus-infected hepatocytes

Hepatitis C virus (HCV) infection of hepatocytes promotes liver fibrosis by activation of hepatic stellate cells (HSCs) and excessive deposition of extracellular matrix in liver tissue. Whether or not host factors released from the HCV-infected hepatocytes play role in HSCs activation is unclear. In this study, HSCs were activated by the conditioned medium derived from HCV replicon cells. Secretomic profiling of HCV replicon cells and the parental Huh7 cells revealed ubiquitin carboxy-terminal hydrolase L1 (UCHL1) as a novel secreted protein from HCV-infected hepatocytes. UCHL1 expression in hepatocytes was induced by HCV infection. UCHL1 was expressed in the liver and found in the plasma of patients with chronic hepatitis C. Molecular analysis by use of the anti-UCHL1 neutralization antibody and purified UCHL1 protein showed that secreted UCHL1 protein was bound to the cell surface of HSCs and activated JNK signaling leading to overexpression of alpha-smooth muscle actin and the activation of HSCs. These results provide further for understanding the underlying mechanism in HCV-mediated hepatic fibrogenesis.

Involvement of Nrf2-mediated heme oxygenase-1 expression in anti-inflammatory action of chitosan oligosaccharides through MAPK activation in murine macrophages

Chitosan and its derivatives have been reported to have anti-inflammatory effects in vitro and in vivo. It is also suggested that chitosan and its derivatives could be up-regulating heme oxygenase-1 (HO-1) in different models. However, the up-regulation of HO-1 by chitosan oligosaccharides (COS) remains unexplored in regard to anti-inflammatory action in lipopolysaccharide (LPS)-stimulated murine macrophages (RAW264.7 cells). Treatment with COS induced HO-1 expression in LPS-stimulated RAW264.7 cells, whereas the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) was decreased. Pretreatment with ZnPP, a HO-1 inhibitor, reduced the COS-mediated anti-inflammatory action. HO-1 induction is mediated by activating the nuclear translocation of NF-E2-related factor 2 (Nrf2) using COS. Moreover, COS increased the phosphorylation of extracellular signal regulated kinase (ERK1/2), c-Jun N-terminal kinase/stress-activated protein kinase (JNK), and p38 MAPK. However, specific inhibitors of ERK, JNK, and p38 reduced COS-mediated nuclear translocation of Nrf2. Therefore, HO-1 induction also decreased in RAW264.7 cells. Collectively, COS exert an anti-inflammatory effect through Nrf2/MAPK-mediated HO-1 induction.

Induction of Nrf2-mediated phase II detoxifying/antioxidant enzymes in vitro by chitosan-caffeic acid against hydrogen peroxide-induced hepatotoxicity through JNK/ERK pathway

Chemical modification of chitosan is a promising method for the improvement of biological activity. In this study, chitosan-caffeic acid (CCA) was prepared and its in vitro hepatoprotective ability against hydrogen peroxide-induced hepatic damage in liver cells was evaluated. Treatment with CCA (50-400 µg/mL) did not show cytotoxicity and also significantly (p < 0.05) recovered cell viability against 650 µM hydrogen peroxide-induced hepatotoxicity. CCA treatment attenuated reactive oxygen species generation and lipid peroxidation in addition to increasing cellular glutathione level in cultured hepatocytes. To validate the underlying mechanism, antioxidant and phase II detoxifying enzyme expressions, which are mediated by NF-E2-related factor 2 (Nrf2) activation, were analyzed and CCA treatment was found to increase the expression of superoxide dismutase-1 (SOD-1), glutathione reductase (GR), heme oxygenase-1 (HO-1), and NAD(P)H:quinine oxidoreductase 1 (NQO1). CCA treatment resulted in increased Nrf2 nuclear translocation. The phosphorylation of extracellular regulated kinase (ERK), c-Jun NH₂-terminal kinase (JNK), and p38 mitogen-activated protein kinase (MAPK) by CCA treatment contributed to Nrf2 activation. Pharmacological blockade of ERK, JNK, and p38 MAPK revealed that SP600125 (JNK inhibitor) and PD98059 (ERK inhibitor) treatment reduced Nrf2 translocation into the nucleus while SB203580 (p38 inhibitor) exhibited weak inhibition. Collectively, CCA protects liver cells against hydrogen peroxide-induced injury and this ability is attributed to the induction of antioxidants and phase II detoxifying enzymes that are mediated by Nrf2 translocation via JNK/ERK signaling.

Hepatic B cell leukemia-3 suppresses chemically-induced hepatocarcinogenesis in mice through altered MAPK and NF-κB activation

The transcriptional nuclear factor kappa B (NF-κB)-coactivator B cell leukemia-3 (Bcl-3) is a molecular regulator of cell death and proliferation. Bcl-3 has been shown to be widely expressed in different cancer types including hepatocellular carcinoma (HCC). Its influence on hepatocarcinogenesis is still undetermined. To examine the role of Bcl-3 in hepatocarcinogenesis mice with hepatocyte-specific overexpression of Bcl-3 (Bcl-3^Hep) were exposed to diethylnitrosamine (DEN) and phenobarbital (PB). Hepatic Bcl-3 overexpression attenuated DEN/PB-induced hepatocarcinogenesis. Bcl-3^Hep mice exhibited a lower number and smaller tumor nodules in response to DEN/PB at 40 weeks of age. Reduced HCC formation was accompanied by a lower rate of cell proliferation and a distinct expression pattern of growth and differentiation-related genes. Activation of c-Jun N-terminal kinase (JNK) and especially extracellular-signal regulated kinase (ERK) was reduced in tumor and tumor-surrounding liver tissue of Bcl-3^Hep mice, while p38 and NF-κB p65 were phosphorylated to a higher extent compared to the wild type. In parallel, the absolute number of intrahepatic macrophages, CD8⁺ T cells and activated B cells was reduced in DEN/PB-treated Bcl-3^Hep mice mirroring a reduction of tumor-associated inflammation. Interestingly, at the early time point of 7 weeks following tumor initiation, a higher rate of apoptotic cell death was observed in Bcl-3^Hep mice. In summary, hepatocyte-restricted Bcl-3 overexpression reduced hepatocarcinogenesis related to prolonged liver injury early after tumor initiation likely due to decreased survival of DEN/PB-damaged, premalignant cells. Therefore, Bcl-3 could become a novel player in the development of therapeutic and diagnostic tools for HCC.

Hepatoprotective effects of lactic acid-fermented garlic extract against acetaminophen-induced acute liver injury in rats

The aim of the present study was to investigate the protective effect of fermented garlic extract by lactic acid bacteria (LAFGE) against acetaminophen (AAP)-induced acute liver injury in rats. Here we demonstrated that rats treated with LAFGE exhibit resistance to AAP-induced liver injury accompanied by lowered plasma alanine amino transferase levels and decreased proinflammatory responses. This function of LAFGE is linked to its capacity of suppressing AAP-induced apoptosis in the liver, partly via the inhibition of MAPK phosphorylation as well as down-regulation of p53. Our findings reveal that LAFGE modulates the signaling pathways involved in hepatic apoptosis through cellular redox control, as indicated by the inhibition of lipid peroxidation, glutathione and ATP depletion, and the elevation of antioxidant enzyme activities. Taken together, these findings indicate that LAFGE ameliorates AAP-induced liver injury by preventing oxidative stress-mediated apoptosis, thereby establishing LAFGE as a potential supplement in the treatment of AAP-induced liver injury.

Mechanisms of Diabetes-Induced Liver Damage: The role of oxidative stress and inflammation

Diabetes mellitus is a non-communicable disease that occurs in both developed and developing countries. This metabolic disease affects all systems in the body, including the liver. Hyperglycaemia, mainly caused by insulin resistance, affects the metabolism of lipids, carbohydrates and proteins and can lead to non-alcoholic fatty liver disease, which can further progress to non-alcoholic steatohepatitis, cirrhosis and, finally, hepatocellular carcinomas. The underlying mechanism of diabetes that contributes to liver damage is the combination of increased oxidative stress and an aberrant inflammatory response; this activates the transcription of pro-apoptotic genes and damages hepatocytes. Significant involvement of pro-inflammatory cytokines-including interleukin (IL)-1β, IL-6 and tumour necrosis factor-α-exacerbates the accumulation of oxidative damage products in the liver, such as malondialdehyde, fluorescent pigments and conjugated dienes. This review summarises the biochemical, histological and macromolecular changes that contribute to oxidative liver damage among diabetic individuals.

Tangeretin Alleviates Cisplatin-Induced Acute Hepatic Injury in Rats: Targeting MAPKs and Apoptosis

Despite its broad applications, cisplatin affords considerable nephro- and hepatotoxicity through triggering inflammatory and oxidative stress cascades. The aim of the current investigation was to study the possible protective effects of tangeretin on cisplatin-induced hepatotoxicity. The impact of tangeretin on cisplatin-evoked hepatic dysfunction and histopathologic changes along with oxidative stress, inflammatory and apoptotic biomarkers were investigated compared to silymarin. Tangeretin pre-treatment significantly improved liver function tests (ALT and AST), inhibited cisplatin-induced lipid profile aberrations (total cholesterol and triglycerides) and diminished histopathologic structural damage in liver tissues. Tangeretin also attenuated cisplatin-induced hepatic inflammatory events as indicated by suppression of tumor necrosis factor-α (TNF-α) and enhancement of interleukin-10 (IL-10). Meanwhile, it lowered malondialdehyde (MDA), nitric oxide (NO) and nuclear factor erythroid 2-related factor 2 (NRF-2) levels with restoration of glutathione (GSH), and glutathione peroxidase (GPx). Regarding mitogen-activated protein kinase (MAPK) pathway, tangeretin attenuated cisplatin-induced increase in phospho-p38, phospho-c-Jun N-terminal kinase (p-JNK) and phospho-extracellular signal-regulated kinase (p-ERK1/2) in liver tissues. In addition, tangeretin downregulated Bax expression with augmentation of Bcl-2 promoting liver cell survival. Our results highlight the protective effects of tangeretin against cisplatin-induced acute hepatic injury via the concerted modulation of inflammation, oxidative stress, MAPKs and apoptotic pathways.

Activation of c-Jun predicts a poor response to sorafenib in hepatocellular carcinoma: Preliminary Clinical Evidence

We determined the mitogen-activated protein kinase (MAPK) gene expression profile of acquired resistance in sorafenib-sensitive hepatocellular carcinoma (HCC) cells and aimed to identify c-Jun as an important molecule mediating the efficacy of sorafenib. Differences in gene expression of the MAPK signaling between untreated and sorafenib-treated HCC cell lines were investigated using real-time polymerase chain reaction array. Western blot and real-time PCR further evaluated the expression of c-Jun. Pathological specimens from 50 patients with advanced HCC were collected to measure p-c-Jun expression. Sorafenib-resistant HCC cells demonstrated greater levels of basal c-Jun mRNA and protein compared with sorafenib-sensitive HCC cells. Sorafenib activated p-c-Jun in a dose- and time-dependent manner in PLC/PRF/5 and MHCC97H cell lines. Decreased expression levels of 6 genes after sorafenib treatment suggested a robust inhibitory impact of sorafenib on MAPK signaling in HCC cells. c-Jun and p-c-Jun expression levels were inversely correlated with the efficacy of sorafenib; a high expression level of p-c-Jun was associated with resistance to sorafenib and poor overall survival in patients with clinical HCC. p-c-Jun may act as a biomarker for predicting responses of sorafenib treatment, thus advocating targeting of JNK/c-Jun signaling as an optimal therapeutic strategy in a subset of HCC.

Protection against acetaminophen-induced acute liver failure by omentum adipose tissue derived stem cells through the mediation of Nrf2 and cytochrome P450 expression

Background

Acetaminophen (APAP) overdose causes acute liver failure (ALF) in animals and humans via the rapid depletion of intracellular glutathione (GSH) and the generation of excess reactive oxygen species (ROS) that damage hepatocytes. Stem cell therapy is a potential treatment strategy for ALF.

Methods

We isolated mesenchymal stem cells (MSCs) from mice omentum adipose tissue-derived stem cells (ASCs) and transplanted them into a mouse model of APAP-induced ALF to explore their therapeutic potential. In addition, we performed in vitro co-culture studies with omentum-derived ASCs and primary isolated hepatocytes to demonstrate the hepatoprotective effect of omentum-derived ASCs on hepatocytes that were subjected to APAP-induced damage.

Result

ASC transplantation significantly improved the survival rate of mice with ALF and attenuated the severity of APAP-induced liver damage by suppressing cytochrome P450 activity to reduce the accumulation of toxic nitrotyrosine and the upregulation of NF-E2-related factor 2 (Nrf2) expression, resulting in an increase in the subsequent antioxidant activity. These effects protected the hepatocytes from APAP-induced damage through the suppression of downstream MAPK signal activation and inflammatory cytokine production.

Conclusions

our results demonstrate that omentum-derived ASCs are an alternative source of ASCs that regulate the antioxidant response and may represent a beneficial therapeutic strategy for ALF.

Protein-protein interaction network analysis of cirrhosis liver disease

AIM

Evaluation of biological characteristics of 13 identified proteins of patients with cirrhotic liver disease is the main aim of this research.

BACKGROUND

In clinical usage, liver biopsy remains the gold standard for diagnosis of hepatic fibrosis. Evaluation and confirmation of liver fibrosis stages and severity of chronic diseases require a precise and noninvasive biomarkers. Since the early detection of cirrhosis is a clinical problem, achieving a sensitive, specific and predictive novel method based on biomarkers is an important task.

METHODS

Essential analysis, such as gene ontology (GO) enrichment and protein-protein interactions (PPI) was undergone EXPASy, STRING Database and DAVID Bioinformatics Resources query.

RESULTS

Based on GO analysis, most of proteins are located in the endoplasmic reticulum lumen, intracellular organelle lumen, membrane-enclosed lumen, and extracellular region. The relevant molecular functions are actin binding, metal ion binding, cation binding and ion binding. Cell adhesion, biological adhesion, cellular amino acid derivative, metabolic process and homeostatic process are the related processes. Protein-protein interaction network analysis introduced five proteins (fibroblast growth factor receptor 4, tropomyosin 4, tropomyosin 2 (beta), lectin, Lectin galactoside-binding soluble 3 binding protein and apolipoprotein A-I) as hub and bottleneck proteins.

CONCLUSION

Our result indicates that regulation of lipid metabolism and cell survival are important biological processes involved in cirrhosis disease. More investigation of above mentioned proteins will provide a better understanding of cirrhosis disease.

Targeted deletion of ER chaperone GRP94 in the liver results in injury, repopulation of GRP94-positive hepatocytes, and spontaneous hepatocellular carcinoma development in aged mice

Hepatocellular carcinoma (HCC) often results from chronic liver injury and severe fibrosis or cirrhosis, but the underlying molecular pathogenesis is unclear. We previously reported that deletion of glucose regulated protein 94 (GRP94), a major endoplasmic reticulum chaperone, in the bone marrow and liver leads to progenitor/stem cell expansion. Since liver progenitor cell (LPC) proliferation can contribute to liver tumor formation, here we examined the effect of GRP94 deficiency on spontaneous liver tumorigenesis. Utilizing liver-specific Grp94 knockout mice driven by Albumin-Cre (cGrp94(f/f)), we discovered that while wild-type livers are tumor free up to 24 months, cGrp94(f/f) livers showed abnormal small nodules at 15 months and developed HCC and ductular reactions (DRs) by 21 months of age, associating with increased liver injury, apoptosis and fibrosis. cGrp94(f/f) livers were progressively repopulated by GRP94-positive hepatocytes. At 15 months, we observed expansion of LPCs and mild DRs, as well as increase in cell proliferation. In examining the underlying mechanisms for HCC development in cGrp94(f/f) livers, we detected increase in TGF-β1, activation of SMAD2/3, ERK, and JNK, and cyclin D1 upregulation at the premalignant stage. While epithelial-mesenchymal transition (EMT) was not evident, E-cadherin expression was elevated. Correlating with the recurrence of GRP94 positive-hepatocytes, the HCC was found to be GRP94-positive, whereas the expanded LPCs and DRs remained GRP94-negative. Collectively, this study uncovers that GRP94 deficiency in the liver led to injury, LPC expansion, increased proliferation, activation of oncogenic signaling, progressive repopulation of GRP94-positive hepatocytes and HCC development in aged mice.

Astaxanthin Pretreatment Attenuates Hepatic Ischemia Reperfusion-Induced Apoptosis and Autophagy via the ROS/MAPK Pathway in Mice

Background: Hepatic ischemia reperfusion (IR) is an important issue in complex liver resection and liver transplantation. The aim of the present study was to determine the protective effect of astaxanthin (ASX), an antioxidant, on hepatic IR injury via the reactive oxygen species/mitogen-activated protein kinase (ROS/MAPK) pathway. Methods: Mice were randomized into a sham, IR, ASX or IR + ASX group. The mice received ASX at different doses (30 mg/kg or 60 mg/kg) for 14 days. Serum and tissue samples at 2 h, 8 h and 24 h after abdominal surgery were collected to assess alanine aminotransferase (ALT), aspartate aminotransferase (AST), inflammation factors, ROS, and key proteins in the MAPK family. Results: ASX reduced the release of ROS and cytokines leading to inhibition of apoptosis and autophagy via down-regulation of the activated phosphorylation of related proteins in the MAPK family, such as P38 MAPK, JNK and ERK in this model of hepatic IR injury. Conclusion: Apoptosis and autophagy caused by hepatic IR injury were inhibited by ASX following a reduction in the release of ROS and inflammatory cytokines, and the relationship between the two may be associated with the inactivation of the MAPK family.

High Concentrations of Atmospheric Ammonia Induce Alterations in the Hepatic Proteome of Broilers (Gallus gallus): An iTRAQ-Based Quantitative Proteomic Analysis

With the development of the poultry industry, ammonia, as a main contaminant in the air, is causing increasing problems with broiler health. To date, most studies of ammonia toxicity have focused on the nervous system and the gastrointestinal tract in mammals. However, few detailed studies have been conducted on the hepatic response to ammonia toxicity in poultry. The molecular mechanisms that underlie these effects remain unclear. In the present study, our group applied isobaric tags for relative and absolute quantitation (iTRAQ)-based quantitative proteomic analysis to investigate changes in the protein profile change in hepatic tissue of broilers exposed to high concentrations of atmospheric ammonia, with the goal of characterizing the molecular mechanisms of chronic liver injury from exposure to high ambient levels of ammonia. Overall, 30 differentially expressed proteins that are involved in nutrient metabolism (energy, lipid, and amino acid), immune response, transcriptional and translational regulation, stress response, and detoxification were identified. In particular, two of these proteins, beta-1 galactosidase (GLB1) and a kinase (PRKA) anchor protein 8-like (AKAP8 L), were previously suggested to be potential biomarkers of chronic liver injury. In addition to the changes in the protein profile, serum parameters and histochemical analyses of hepatic tissue also showed extensive hepatic damage in ammonia-exposed broilers. Altogether, these findings suggest that longtime exposure to high concentrations of atmospheric ammonia can trigger chronic hepatic injury in broilers via different mechanisms, providing new information that can be used for intervention using nutritional strategies in the future.

S100A9 promotes human hepatocellular carcinoma cell growth and invasion through RAGE-mediated ERK1/2 and p38 MAPK pathways

S100A9 belongs to the S100 family of calcium-binding proteins and is over-expressed in many human tumors including hepatocellular carcinoma (HCC). Recent study demonstrated that S100A9 is significantly elevated and is associated with tumor differentiation and vascular invasion in HCC. The functional role of S100A9 is, however, poorly understood. Here, we demonstrated that S100A9 treatment increased viability, invasiveness and clone formation in three HCC cell lines (HepG2, SMMC-7721 and Huh7). S100A9 also promoted tumor growth in vivo by a xenograft mouse model. In addition, we observed a co-localization of S100A9 with receptor for advanced glycation end products (RAGE) in human HCC intratumoral tissues and an interaction of S100A9 with RAGE in vitro. Treatment with RAGE blocking antibody blocked the enhanced viability, invasion, clone formation and tumor growth in vivo resulted by S100A9, suggesting that these effects were mediated via RAGE ligation. In order to investigate the signaling pathways, mitogen-activated protein kinase (MAPK) phosphorylation was characterized. S100A9 caused a significant increase in p-p38 and p-ERK1/2 levels, and inhibition of which blocked enhanced invasion and viability resulted by S100A9, respectively. Furthermore, treatment with RAGE blocking antibodies also abrogated the S100A9-induced p38 and ERK1/2 activation, suggesting that S100A9-induced MAPK activation is mediated via RAGE ligation. Our data demonstrate that S100A9 binds to RAGE and stimulates RAGE-dependent MAPK signaling cascades, promoting cell growth and invasion in HCC.

KEAP the balance between life and death

Hepatocyte apoptosis in association with oxidative stress represent key pathogenic factors involved in tumor development in patients with non-alcoholic fatty liver disease (NAFLD). In our recent study, we established that cellular degradation of Kelch-like ECH-associated protein 1 (KEAP1) through sequestrosome (SQSTM)1/p62-dependent autophagy activates c-Jun NH2 terminal kinase (JNK), upregulates expression of Bcl-2-interacting mediator (BIM) and p53 upregulated modulator of apoptosis (PUMA), and contributes to hepatocyte apoptosis induced by saturated free fatty acids. These findings raise the possibility that dysregulation of KEAP1 may contribute to liver cell death and tumorigenesis during chronic inflammatory liver disease.

Development of a novel azaspirane that targets the Janus kinase-signal transducer and activator of transcription (STAT) pathway in hepatocellular carcinoma in vitro and in vivo

Signal transducer and activator of transcription 3 (STAT3) is a transcription factor that regulates genes involved in cell growth, proliferation, and survival, and given its association with many types of cancers, it has recently emerged as a promising target for therapy. In this work, we present the synthesis of N-substituted azaspirane derivatives and their biological evaluation against hepatocellular carcinoma (HCC) cells (IC50 = 7.3 μm), thereby identifying 2-(1-(4-(2-cyanophenyl)1-benzyl-1H-indol-3-yl)-5-(4-methoxy-phenyl)-1-oxa-3-azaspiro(5,5) undecane (CIMO) as a potent inhibitor of the JAK-STAT pathway with selectivity over normal LO2 cells (IC50 > 100 μm). The lead compound, CIMO, suppresses proliferation of HCC cells and achieves this effect by reducing both constitutive and inducible phosphorylation of JAK1, JAK2, and STAT3. Interestingly, CIMO displayed inhibition of Tyr-705 phosphorylation, which is required for nuclear translocation of STAT3, but it has no effect on Ser-727 phosphorylation. CIMO accumulates cancer cells in the sub-G1 phase and decreases STAT3 in the nucleus and thereby causes down-regulation of genes regulated via STAT3. Suppression of STAT3 phosphorylation by CIMO and knockdown of STAT3 mRNA using siRNA transfection displayed a similar effect on the viability of HCC cells. Furthermore, CIMO significantly decreased the tumor development in an orthotopic HCC mouse model through the modulation of phospho-STAT3, Ki-67, and cleaved caspase-3 in tumor tissues. Thus, CIMO represents a chemically novel and biologically in vitro and in vivo validated compound, which targets the JAK-STAT pathway as a potential cancer treatment.

LPS promotes epithelial-mesenchymal transition and activation of TLR4/JNK signaling

The endotoxin level in the portal and peripheral veins of hepatocellular carcinoma (HCC) patients is higher and lipopolysaccharide (LPS), has been reported to inhibit tumor growth. However, in this study, we found that LPS-induced Toll-like receptor 4 (TLR4) signaling was involved in tumor invasion and the molecular mechanism was investigated. The HCC cells were used to study the invasion ability of LPS-induced HCC cells and the epithelial-mesenchymal transition (EMT) in vitro. The in vitro experiments demonstrated that LPS could significantly enhance the invasive potential and induce EMT in HCC cells with TLR4 dependent. Further studies showed that LPS could directly activate JNK/MAPK signaling through TLR4 in HCC cells. Interestingly, blocking JNK/MAPK signaling significantly inhibited EMT occurrence. Our results indicate that TLR4/JNK/MAPK signaling is required for LPS-induced EMT, tumor cell invasion and metastasis, which provide molecular insights for LPS-related pathogenesis and a basis for developing new strategies against metastasis in HCC.