Dissection of the multiple mechanisms of TNF-alpha-induced apoptosis in liver injury

Protective effect of Macleaya cordata isoquinoline alkaloids on lipopolysaccharide-induced liver injury in broilers

OBJECTIVE

This experiment aimed to explore the protective action of dietary supplementation with isoquinoline alkaloids (IA) from Macleaya cordata on lipopolysaccharide (LPS)-induced liver injury in broilers.

METHODS

Total 216 healthy broilers were selected in a 21-d trial and assigned randomly to the following 3 treatments: control (CON) group, LPS group, and LPS+IA group. The CON and LPS groups were provided with a basal diet, whereas the LPS+IA group received the basal diet supplemented with 0.6 mg/kg Macleaya cordata IA. Broilers in LPS and LPS+IA groups were intraperitoneally injected with LPS (1 mg/kg body weight) at 17, 19, and 21 days of age, while those in CON group were injected with equivalent amount of saline solution.

RESULTS

Results showed LPS injection caused systemic and liver inflammation in broilers, inhibited immune function, and ultimately lead to liver injury. By contrast, supplementation of IA ameliorated LPS-induced adverse change in serum parameters, boosted immunity in LPS+IA group. Furthermore, IA suppressed the elevation of hepatic inflammatory cytokines and caspases levels induced by LPS, as well as the expressions of genes related to the tolllike receptor 4 (TLR4)/myeloid differentiation primary response 88 (MyD88)/nuclear factorkappa B (NF-κB) pathway.

CONCLUSION

Dietary inclusion of 0.6 mg/kg Macleaya cordata IA could enhance immune function of body and inhibit liver damage via inactivating TLR4/MyD88/NF-κB signaling pathway in broilers.

Pasteurella multocida causes liver injury in ducks by mediating inflammatory, apoptotic and autophagic pathways

Pasteurella multocida.(PM) infection is a major cause of avian cholera, but the pathogenesis of the disease is unknown. The purpose of this study was to further understand the host response to infection by using a duck model of PM, 20 female ducks were divided into two groups (n = 10). One group was infected with PM, while the other served as an uninfected control group. The ducks were observed after infection and samples were collected for testing. In this study, we report the mechanism of PM-induced inflammation to further mediate apoptosis and autophagic signaling pathways in liver cells. Our results demonstrated that PM infection initially induces hemorrhagic and necrotic lesions in the liver tissue of duck, promoting inflammasome assembly and release, triggering inflammation. The TLR4/NF-κB axis activated and interacted with multiple inflammation-related proteins, including TNF-α and IL-1β, which affected apoptosis and autophagy. Tumor necrosis factor induced hepatocyte apoptosis was implicated in a wide range of liver diseases; the release of TNF-α and activation with NF-κB further incite apoptotic pathways,such as Bax/BCL2/caspase to promote apoptotic genes APAF1, Bax, Caspase3, BCL-2, p53, and Cytc expression. Finally, PM-induced autophagy suppressed liver injury by promoting the Beclin-1, LC3B, p62, and mTOR. Thus, liver injury caused by PM via promoting autophagy was induced. In conclusion, we analyzed the liver injury of ducks infected with PM, and confirmed that inflammation appeared in the liver; this was followed by the intricate interplay between inflammation, apoptosis, and autophagy signaling pathways. The observed results provided a reference basis for studying pathogenic mechanisms of PM-host interactions.

Garlic-derived exosome-like nanovesicles as a hepatoprotective agent alleviating acute liver failure by inhibiting CCR2/CCR5 signaling and inflammation

Acute liver failure (ALF) is a life-threatening clinical syndrome mostly induced by viral infections or drug abuse. As a novel therapeutic adjuvant or delivery vehicle, plant-derived exosome-like nanovesicles (PELNVs) have been extensively studied in recent years. This study aimed to develop garlic-derived exosome-like nanovesicles (GaELNVs) in order to ameliorate liver injury induced by LPS/D-GalN in mice, inhibit inflammatory eruption and reduce inflammatory cells infiltration. The results showed that treatment with GaELNVs improved liver pathology and reduced the levels of soluble inflammatory mediators IL-6, IL-1β and TNF-α in the serum of ALF mice. GaELNVs reversed the upregulation of Cleaved Caspase-9, Cleaved Caspase-3, p53 and Bax expression and decreased Bcl2 activation caused by D-GalN/LPS, and inhibited NF-κB p65 expression and translocation to the nucleus. Meanwhile, treatment with GaELNVs resulted significant reduction in NLRP3 activation and Caspase-1 maturation, as well as decrease in the release of the inflammatory mediator IL-18. Additionally, an upregulation of the expression of proteins related to energy metabolism and autophagy occurrence including Foxo3a, Sirt1, and LC3-II was detected in the liver. Oral administration of GaELNVs also led to significant alteration in the expression of F4/80 and CD11b in the liver. Furthermore, the detection of chemokines in mouse liver tissue revealed that GaELNVs exhibited minimal reduction in the expression of CCL2, CCL3, CCL5 and CCL8. The decreased expression of CCR2 and CCR5 in the liver suggests that GaELNVs have the ability to decrease the recruitment of monocytes from the circulation to the liver. A reduction in the infiltration of F4/80loCD11bhi monocyte-derived macrophages into the liver was also observed. This study provides novel evidence that GaELNVs can ameliorate inflammatory eruptions and hinder the migration of circulating monocytes to the liver, as well as decrease macrophage infiltration by inhibiting CCR2/CCR5 signaling. Consequently, GaELNVs hold promise as a novel therapeutic agent for clinical management of liver disease.

Anti-inflammatory and antinociceptive effects, and safety toxicological profile of a new paracetamol analog, LQFM291

In the scope of a research program with the goal of developing treatments for inflammatory diseases, the pharmacological evaluation of LQFM291, designed by molecular hybridization from butylated hydroxytoluene and paracetamol, was described. The antioxidant profile of LQFM291 was evaluated by electrochemical measurement. Also, acute or repeated treatments with equimolar doses to paracetamol were used to evaluate the antinociceptive and/or anti-inflammatory activities of LQFM291 in animal models. The toxicologic potential of LQFM291 was also evaluated and compared to paracetamol through biochemical and histopathological analysis after the repeated treatment schedule. As a result of the acute treatment, paracetamol showed a similar antinociceptive effect in formalin test compared to LQFM291. Whereas, after the repeated treatment, when carrageenan-induced hyperalgesia and edema tests were performed, paracetamol showed a delayed antinociceptive and anti-inflammatory effect compared to LQFM291. Furthermore, as other advantages the LQFM291 showed a high redox capacity, a gastroprotective activity and a safety pharmacological profile without any liver or kidney damage. These effects can be related to the prevention of oxidative stress by reduction of protein and lipid peroxidation in gastric tissue, maintenance of glutathione levels in hepatic homogenate, and a systemic reduction of pro-inflammatory cytokine levels, which may characterize the LQFM291 as a more viable and effective alternative to relief pain and inflammatory signs in patients with chronic disorders.

Bioinformatic and systems biology approach revealing the shared genes and molecular mechanisms between COVID-19 and non-alcoholic hepatitis

Introduction: Coronavirus disease 2019 (COVID-19) has become a global pandemic and poses a serious threat to human health. Many studies have shown that pre-existing nonalcoholic steatohepatitis (NASH) can worsen the clinical symptoms in patients suffering from COVID-19. However, the potential molecular mechanisms between NASH and COVID-19 remain unclear. To this end, key molecules and pathways between COVID-19 and NASH were herein explored by bioinformatic analysis. Methods: The common differentially expressed genes (DEGs) between NASH and COVID-19 were obtained by differential gene analysis. Enrichment analysis and protein-protein interaction (PPI) network analysis were carried out using the obtained common DEGs. The key modules and hub genes in PPI network were obtained by using the plug-in of Cytoscape software. Subsequently, the hub genes were verified using datasets of NASH (GSE180882) and COVID-19 (GSE150316), and further evaluated by principal component analysis (PCA) and receiver operating characteristic (ROC). Finally, the verified hub genes were analyzed by single-sample gene set enrichment analysis (ssGSEA) and NetworkAnalyst was used for the analysis of transcription factor (TF)-gene interactions, TF-microRNAs (miRNA) coregulatory network, and Protein-chemical Interactions. Results: A total of 120 DEGs between NASH and COVID-19 datasets were obtained, and the PPI network was constructed. Two key modules were obtained via the PPI network, and enrichment analysis of the key modules revealed the common association between NASH and COVID-19. In total, 16 hub genes were obtained by five algorithms, and six of them, namely, Kruppel-like factor 6 (KLF6), early growth response 1 (EGR1), growth arrest and DNA-damage-inducible 45 beta (GADD45B), JUNB, FOS, and FOS-like antigen 1 (FOSL1) were confirmed to be closely related to NASH and COVID-19. Finally, the relationship between hub genes and related pathways was analyzed, and the interaction network of six hub genes was constructed with TFs, miRNAs, and compounds. Conclusion: This study identified six hub genes related to COVID-19 and NASH, providing a new perspective for disease diagnosis and drug development.

Kindlin-2 inhibits TNF/NF-κB-Caspase 8 pathway in hepatocytes to maintain liver development and function

Inflammatory liver diseases are a major cause of morbidity and mortality worldwide; however, underlying mechanisms are incompletely understood. Here we show that deleting the focal adhesion protein Kindlin-2 expression in hepatocytes using the Alb-Cre transgenic mice causes a severe inflammation, resulting in premature death. Kindlin-2 loss accelerates hepatocyte apoptosis with subsequent compensatory cell proliferation and accumulation of the collagenous extracellular matrix, leading to massive liver fibrosis and dysfunction. Mechanistically, Kindlin-2 loss abnormally activates the tumor necrosis factor (TNF) pathway. Blocking activation of the TNF signaling pathway by deleting TNF receptor or deletion of Caspase 8 expression in hepatocytes essentially restores liver function and prevents premature death caused by Kindlin-2 loss. Finally, of translational significance, adeno-associated virus mediated overexpression of Kindlin-2 in hepatocytes attenuates the D-galactosamine and lipopolysaccharide-induced liver injury and death in mice. Collectively, we establish that Kindlin-2 acts as a novel intrinsic inhibitor of the TNF pathway to maintain liver homeostasis and may define a useful therapeutic target for liver diseases.

Histopathological, ultrastructural, and biochemical traits of apoptosis induced by peroxisomicine A1 (toxin T-514) from Karwinskia parvifolia in kidney and lung

Peroxisomicine A1 (PA1) is a toxin isolated from the Karwinskia genus plants whose target organs are the liver, kidney, and lung. In vitro studies demonstrated the induction of apoptosis by PA1 in cancer cell lines, and in vivo in the liver. Apoptosis has a wide range of morphological features such as cell shrinkage, plasma membrane blistering, loss of microvilli, cytoplasm, and chromatin condensation, internucleosomal DNA fragmentation, and formation of apoptotic bodies that are phagocytized by resident macrophages or nearby cells. Early stages of apoptosis can be detected by mitochondrial alterations. We investigated the presence of apoptosis in vivo at the morphological, ultrastructural, and biochemical levels in two target organs of PA1: kidney and lung. Sixty CD-1 mice were divided into three groups (n = 20): untreated control (ST), vehicle control (VH), and PA1 intoxicated group (2LD50). Five animals of each group were sacrificed at 4, 8, 12, and 24 h post-intoxication. Kidney and lung were examined by morphometry, histopathology, ultrastructural, and DNA fragmentation analysis. Pre-apoptotic mitochondrial alterations were present at 4 h. Apoptotic bodies were observed at 8 h and increased over time. TUNEL positive cells were detected as early as 4 h, and the DNA ladder pattern was observed at 12 h and 24 h. The liver showed the highest value of fragmented DNA, followed by the kidney and the lung. We demonstrated the induction of apoptosis by a toxic dose of PA1 in the kidney and lung in vivo. These results could be useful in understanding the mechanism of action of this compound at toxic doses in vivo.

To discuss the mechanism of colchicine in the treatment of acute cerebral infarction based on network pharmacology

To explore the mechanism of action of colchicine in the treatment of acute cerebral infarction (ACI) based on network pharmacology. The Swiss Target Prediction Database and CTD database were used to predict the target information of colchicine. ACI-related targets were retrieved using the GeneCards database, and the target protein interaction network (PPI) and active ingredient-target network were obtained by combining Cytoscape 3.7.1 software and R language. Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis and gene function analysis (GO) enrichment analysis were performed using R language to preliminarily explore the multiple pharmacological mechanisms of action of colchicine. There were 200 targets identified by network parameter analysis; 958 ACI targets were identified. Overlapping comparisons allowed the extraction of 143 overlapping targets, and the top 30 targets were screened according to the topological isomerization parameters. Component-target networks were constructed. A PPI of overlapping targets was established to identify key targets. In addition, Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis and GO functional enrichment analysis were performed to explore the multiple mechanisms of action of colchicine in the treatment of ACI. Colchicine treatment of ACI is characterized by multi-component, multi-target and multi-pathway, and can exert complex network regulation through the interaction between different targets, providing a new idea and new basis for further exploration of the mechanism of action of colchicine in the treatment of ACI.

Hepatoprotective effect of Physalis divaricata in paracetamol induced hepatotoxicity: In vitro, in silico and in vivo analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Physalis divaricata D. Don. is an erect weed of family Solanaceae. The root extract of this plant is used by the indigenous communities of Sub-Himalayan region of Uttarakhand, India for the treatment of liver disorders.

AIM OF THE STUDY

To evaluate hepatoprotective potential of P. divaricata in paracetamol (PCM) induced hepatotoxicity in rats.

MATERIALS AND METHODS

The dried roots of P. divaricata were subjected to extraction using different solvents. The chloroform extract, methanol extract and bioactive aqueous fraction of methanol extract were evaluated for hepatoprotective effect. After initial in vitro screening, all extracts were screened for hepatoprotective potential in PCM (3 g/kg p.o) induced hepatotoxicity. Following PCM administration, extracts were administered orally for 7 days in increasing dose concentrations. All the animals were euthanized on eighth day, serum and liver tissues were collected and subjected to various biochemical and histopathological analysis. Aqueous fraction of methanol extract was further analyzed using LC- MS analysis.

RESULTS

Methanol extract and its bioactive aqueous fraction exhibited significant and better in vitro antioxidant and antiproliferative activity as compared to chloroform extract. PCM treatment caused hepatotoxicity as assessed by altered levels of various hepatic biomarkers (increase in the levels of ALT, AST, ALP, albumin, triglycerides, cholesterol, TBARS, and AOPPs as well as decrease in GSH and TrxR levels) along with histopathological changes (portal to portal bridging, necrosis, and inflammation). Methanolic extract (200, 400 and 800 mg/kg) and its aqueous fraction treatment (25, 50 and 100 mg/kg) significantly restored elevated hepatic biomarkers, oxidative stress, and protected normal hepato-architecture. LC-MS analysis of aqueous fraction showed presence of rutin and kaempferol. In silico analysis further showed the capability of rutin to make complex with TNF-α and block its interaction with the target site.

CONCLUSION

Aqueous fraction showed maximum hepatoprotective potential as conceived through in vitro and in vivo studies. Presence of rutin may explain hepatoprotective potential of P. divaricata.

Characterization and Roles of Membrane Lipids in Fatty Liver Disease

Obesity has reached global epidemic proportions and it affects the development of insulin resistance, type 2 diabetes, fatty liver disease and other metabolic diseases. Membrane lipids are important structural and signaling components of the cell membrane. Recent studies highlight their importance in lipid homeostasis and are implicated in the pathogenesis of fatty liver disease. Here, we discuss the numerous membrane lipid species and their metabolites including, phospholipids, sphingolipids and cholesterol, and how dysregulation of their composition and physiology contribute to the development of fatty liver disease. The development of new genetic and pharmacological mouse models has shed light on the role of lipid species on various mechanisms/pathways; these lipids impact many aspects of the pathophysiology of fatty liver disease and could potentially be targeted for the treatment of fatty liver disease.

DHEA Protects Human Cholangiocytes and Hepatocytes against Apoptosis and Oxidative Stress

Primary biliary cholangitis (PBC) is a rare chronic cholestatic and immune-mediated liver disease of unknown aetiology that targets intrahepatic bile duct cells (cholangiocytes) and primarily affects postmenopausal women, when their estrogen levels sharply decrease. An impaired cholangiocyte response to estrogen characterizes the terminal stage of the disease, as this is when an inefficiency of cholangiocyte proliferation, in balancing the loss of intrahepatic bile ducts, is observed. Here, we report that the estrogen precursor dehydroepiandrosterone (DHEA) and its sulfate metabolites, DHEA-S and 17 β-estradiol, enhance the proliferation of cholangiocytes and hepatocytes in vitro. Flow cytometry analysis showed that DHEA and DHEA-S decreased glyco-chenodeoxycholic acid (GCDC)-driven apoptosis in cholangiocytes. Cell viability assay (MTT) indicated that ER-α, -β, and the G-protein-coupled estrogen receptor, are involved in the protection of DHEA against oxidative stress in cholangiocytes. Finally, immunoblot analysis showed an elevated level of steroid sulfatase and a reduced level of sulfotransferase 1E1 enzymes, involved in the desulfation/sulfation process of estrogens in cirrhotic PBC, and primary sclerosis cholangitis (PSC) liver tissues, another type of chronic cholestatic and immune-mediated liver disease. Taken together, these results suggest that DHEA can prevent the deleterious effects of certain potentially toxic bile acids and reactive oxygen species, delaying the onset of liver disease.

Sox2 overexpression alleviates noise-induced hearing loss by inhibiting inflammation-related hair cell apoptosis

Background

The transcription factor Sox2 plays important roles in the developmental processes of multiple organs and tissues. However, whether Sox2 can protect mature or terminally differentiated cells against injury is still unknown.

Methods

We investigated the roles of Sox2 in cochlear hair cells, which are terminally differentiated cells, using conditional transgenic mice and several hearing loss models.

Results

Sox2 overexpression dramatically mitigated the degree of cochlear hair cell loss when exposed to ototoxic drugs. Noise-induced apoptosis of cochlear hair cells and hearing loss were also significantly alleviated by Sox2 overexpression. Notably, noise-induced upregulation of pro-inflammatory factors such as TNF-α and IL6 was inhibited by Sox2 overexpression. Then we used lipopolysaccharide to clarify the effect of Sox2 on cochlear inflammation, and Sox2 overexpression significantly inhibited lipopolysaccharide-induced upregulation of pro-inflammatory factors and alleviated inflammation-related cochlear hair cell death.

Conclusions

These results demonstrate a novel protective role of Sox2 in mature and terminally differentiated cochlear hair cells by inhibiting inflammation.

The dynamics of cell death patterns and regeneration during acute liver injury in mice

Acute liver injury is a serious clinical syndrome with multiple causes and unclear pathological process. Here, CCl₄‐ and D‐galactosamine/lipopolysaccharide (D‐gal/LPS)‐induced acute liver injury was established to explore the cell death patterns and determine whether or not liver regeneration occurred. In CCl₄‐induced hepatic injury, three phases, including the early, progressive, and recovery phase, were considered based on alterations of serum transaminases and liver morphology. Moreover, in this model, cytokines exhibited double‐peak fluctuations; apoptosis and pyroptosis persisted throughout all phases; autophagy occurred in the early and the progressive phases; and sufficient and timely hepatocyte regeneration was observed only during the recovery phase. All of these phenomena contribute to mild liver injury and subsequent regeneration. Strikingly, only the early and progressive phases were observed in the D‐gal/LPS model. Slight pyroptosis occurred in the early phase but diminished in the progressive phase, while apoptosis, reduced autophagy, and slight but subsequently diminished regeneration occurred only during the progressive phase, accompanied by a strong cytokine storm, resulting in severe liver injury with high mortality. Taken together, our work reveals variable modes and dynamics of cell death and regeneration, which lead to different consequences for mild and severe acute liver injury, providing a helpful reference for clinical therapy and prognosis.

New phthalimide analog ameliorates CCl4 induced hepatic injury in mice via reducing ROS formation, inflammation, and apoptosis

The present study aimed, for the first time, to examine the biochemical effects of new phthalimide analog, 2-[2-(2-Bromo-1-ethyl-1H-indol-3-yl) ethyl]-1H-isoindole-1,3(2H)-dione, compared to thalidomide drug against liver injury induced in mice. Carbon tetrachloride was intraperitoneal injected in mice for 6 consecutive weeks at a dose of 0.4 mL/kg twice a week for liver injury induction. Histopathological examination, levels of malondialdehyde, nitric oxide, and antioxidant enzymes were determined. Additionally, the protein levels of vascular endothelial growth factor, proliferating cell nuclear protein, tumor necrosis factor-alfa, nuclear factor kappa B-p65, B-cell lymphoma-2, and cysteine-aspartic acid protease-3 were determined. Results revealed that the treatment with phthalimide analog improved the detected liver damage and presented an obvious antioxidant activity through decreasing malondialdehyde and nitric oxide levels accompanied by increasing the levels of the antioxidant enzymes. Furthermore, the analog exhibited an effective inhibitory activity towards the studied protein expressions in liver tissues. Moreover, the B-cell lymphoma-2 protein level was increased while the cysteine-aspartic acid protease-3 level was suppressed after the treatment with phthalimide analog. Together, these results propose that phthalimide analog can ameliorate carbon tetrachloride-induced liver injury in mice through its potent inhibition mediating effect in oxidative stress, inflammation, and apoptosis mechanisms.

Lysimachiae Herba Inhibits Inflammatory Reactions and Improves Lipopolysaccharide/D-Galactosamine-Induced Hepatic Injury

This study aimed to determine the anti-inflammatory and hepatoprotective effects of Lysimachiae Herba ethanolic extract (LHE) in lipopolysaccharide (LPS)-stimulated macrophages and in a LPS/D-galactosamine (GalN)-induced acute hepatitis mouse model. Then, the production of inflammatory mediators and the activation of related pathways in macrophages were explored. Finally, we assessed the serum aminotransferase levels and the expression of inflammatory/antioxidant molecules in liver tissues in mice. Results revealed that LHE treatment significantly inhibited the production of inflammatory mediators in LPS-stimulated RAW 264.7 macrophages. Molecular data showed that LHE remarkably increased the activities of the antioxidant pathway and inhibited the phosphorylation of mitogen-activated protein kinase as well as the transcriptional activity of nuclear factor-κB induced by LPS. Furthermore, it prevented acute liver damage caused by LPS/D-GalN-induced hepatitis by inhibiting aminotransferase levels and histopathological changes in mice. Moreover, treatment with LHE significantly inhibited the activation of inflammatory pathways and increased the expression of antioxidant molecules including heme oxygenase-1/Nuclear factor erythroid 2-related factor 2. In conclusion, LHE has potent anti-inflammatory and hepatoprotective effects in LPS-stimulated macrophages and the LPS/D-GalN-induced acute hepatitis mouse model. Thus, it can be a treatment option for inflammation, hepatitis, and liver injury.

Betaine downregulates microRNA 34a expression via a p53-dependent manner in cisplatin-induced nephrotoxicity in rats

Cisplatin-induced nephrotoxicity limits its wide application as a chemotherapeutic drug. Betaine is a natural trimethylglycine compound involved in several biological reactions. In this study, the protective effect of betaine against cisplatin-induced nephrotoxicity through modulating the expression of microRNA 34a (miRNA 34a), p53, apoptosis, and inflammation was investigated. Adult Wistar rats were divided into normal group (received vehicle); betaine group (received 250 mg betaine/kg BW/day via oral gavage from Day 1 to Day 25); cisplatin group (received a single intraperitoneal dose of cisplatin at 5 mg/kg BW on Day 21) and betaine + cisplatin group (received the same doses of betaine and cisplatin). The results demonstrated that the cisplatin group exhibited severe kidney tissue damage and an increase in blood creatinine and urea levels. Furthermore, the cisplatin group showed a significant upregulation of miRNA 34a and higher levels of phospho-p53, caspase 3, cytochrome c, NF_k B, and IL-1β compared to the normal group. Remarkably, the betaine + cisplatin group showed significantly decreased blood creatinine and urea concentrations, decreased levels of miRNA 34a, phospho-p53, caspase 3, cytochrome c, NF_k B, and IL-1β as well as improved kidney tissue integrity compared to the cisplatin group. In conclusion, cisplatin-induced nephrotoxicity in rats was associated with upregulation of miRNA 34a expression, apoptosis, and inflammation in p53-dependent manner. These effects were reversed by betaine administration that ultimately improved the kidney function and tissue integrity.

Hepatoprotective Effects of Polydatin-Loaded Chitosan Nanoparticles in Diabetic Rats: Modulation of Glucose Metabolism, Oxidative Stress, and Inflammation Biomarkers

Polydatin (PD) has a broad range of pharmacological activities; however, its effects on diabetic liver damage are poorly studies. This work is aimed to explore possible protective effects of polydatin-loaded chitosan nanoparticles (PD-CSNPs) or PD against liver damage associated with diabetes. Diabetes was induced in rats using nicotinamide/streptozotocin treatment. Diabetic rats were then divided into six groups: normal control rats, diabetic control rats, and rats orally treated with PD, PD-CSNPs, equivalent unloaded CSNPs, or metformin daily for 4 weeks. Treatment with PD and PD-CSNPs significantly reduced the blood glucose content, lipid peroxidation in the liver, and activities of serum transaminases and carbohydrate metabolism enzymes (including succinate dehydrogenase and pyruvate kinase); by contrast, liver glycogen content, glutathione concentration, and activities of the antioxidant enzymes (superoxide dismutase, glutathione peroxidase, catalase, and glucose-6-phosphate dehydrogenase) were markedly increased compared with the control diabetic rats. Furthermore, expression of the tumor necrosis factor α and interleukin-1β mRNAs was significantly downregulated, while expression of glucose transporter 2 and glucokinase mRNAs was strongly upregulated vs. control diabetic rats. We concluded that PD-CSNPs and PD ameliorate diabetic liver damage by modulating glucose transporter 2 expression, affecting the activity of carbohydrate metabolism enzymes, and suppressing oxidative stress and inflammation, PD-CSNPs being more efficient than PD, probably due to higher bioavailability and prolonged release.

The Ameliorative Effects of Fucoidan in Thioacetaide-Induced Liver Injury in Mice

Liver disorders have been recognized as one major health concern. Fucoidan, a sulfated polysaccharide extracted from the brown seaweed Fucus serratus, has previously been reported as an anti-inflammatory and antioxidant. However, the discovery and validation of its hepatoprotective properties and elucidation of its mechanisms of action are still unknown. The objective of the current study was to investigate the effect and possible modes of action of a treatment of fucoidan against thioacetamide (TAA)-induced liver injury in male C57BL/6 mice by serum biochemical and histological analyses. The mouse model for liver damage was developed by the administration of TAA thrice a week for six weeks. The mice with TAA-induced liver injury were orally administered fucoidan once a day for 42 days. The treated mice showed significantly higher body weights; food intakes; hepatic antioxidative enzymes (catalase, glutathione peroxidase (GPx), and superoxide dismutase (SOD)); and a lower serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and C-reactive protein (CRP) levels. Additionally, a reduced hepatic IL-6 level and a decreased expression of inflammatory-related genes, such as cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) mRNA was observed. These results demonstrated that fucoidan had a hepatoprotective effect on liver injury through the suppression of the inflammatory responses and acting as an antioxidant. In addition, here, we validated the use of fucoidan against liver disorders with supporting molecular data.

Association of Adipose Tissue and Adipokines with Development of Obesity-Induced Liver Cancer

Obesity is rapidly dispersing all around the world and is closely associated with a high risk of metabolic diseases such as insulin resistance, dyslipidemia, and nonalcoholic fatty liver disease (NAFLD), leading to carcinogenesis, especially hepatocellular carcinoma (HCC). It results from an imbalance between food intake and energy expenditure, leading to an excessive accumulation of adipose tissue (AT). Adipocytes play a substantial role in the tumor microenvironment through the secretion of several adipokines, affecting cancer progression, metastasis, and chemoresistance via diverse signaling pathways. AT is considered an endocrine organ owing to its ability to secrete adipokines, such as leptin, adiponectin, resistin, and a plethora of inflammatory cytokines, which modulate insulin sensitivity and trigger chronic low-grade inflammation in different organs. Even though the precise mechanisms are still unfolding, it is now established that the dysregulated secretion of adipokines by AT contributes to the development of obesity-related metabolic disorders. This review focuses on several obesity-associated adipokines and their impact on obesity-related metabolic diseases, subsequent metabolic complications, and progression to HCC, as well as their role as potential therapeutic targets. The field is rapidly developing, and further research is still required to fully understand the underlying mechanisms for the metabolic actions of adipokines and their role in obesity-associated HCC.

Roles of Ceramides in Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease is one of the most common chronic liver diseases, ranging from simple steatosis to steatohepatitis, fibrosis, and cirrhosis. Its prevalence is rapidly increasing and presently affects around 25% of the general population of Western countries, due to the obesity epidemic. Liver fat accumulation induces the synthesis of specific lipid species and particularly ceramides, a sphingolipid. In turn, ceramides have deleterious effects on hepatic metabolism, a phenomenon called lipotoxicity. We review here the evidence showing the role of ceramides in non-alcoholic fatty liver disease and the mechanisms underlying their effects.

Withaferin A alleviates fulminant hepatitis by targeting macrophage and NLRP3

Fulminant hepatitis (FH) is an incurable clinical syndrome where novel therapeutics are warranted. Withaferin A (WA), isolated from herb Withania Somnifera, is a hepatoprotective agent. Whether and how WA improves D-galactosamine (GalN)/lipopolysaccharide (LPS)-induced FH is unknown. This study was to evaluate the hepatoprotective role and mechanism of WA in GalN/LPS-induced FH. To determine the preventive and therapeutic effects of WA, wild-type mice were dosed with WA 0.5 h before or 2 h after GalN treatment, followed by LPS 30 min later, and then killed 6 h after LPS treatment. To explore the mechanism of the protective effect, the macrophage scavenger clodronate, autophagy inhibitor 3-methyladenine, or gene knockout mouse lines NLR family pyrin domain containing 3 (Nlrp3)-null, nuclear factor-erythroid 2-related factor 2 (Nrf2)-null, liver-specific AMP-activated protein kinase (Ampk)a1 knockout (Ampka1ΔHep) and liver-specific inhibitor of KB kinase β (Ikkb) knockout (IkkbΔHep) mice were subjected to GalN/LPS-induced FH. In wild-type mice, WA potently prevented GalN/LPS-induced FH and inhibited hepatic NLRP3 inflammasome activation, and upregulated NRF2 and autophagy signaling. Studies with Nrf2-null, Ampka1ΔHep, and IkkbΔHep mice demonstrated that the hepatoprotective effect was independent of NRF2, hepatic AMPKα1, and IκκB. Similarly, 3-methyladenine cotreatment failed to abolish the hepatoprotective effect of WA. The hepatoprotective effect of WA against GalN/LPS-induced FH was abolished after macrophage depletion, and partially reduced in Nlrp3-null mice. Consistently, WA alleviated LPS-induced inflammation partially dependent on the presence of NLRP3 in primary macrophage in vitro. Notably, WA potently and therapeutically attenuated GalN/LPS-induced hepatotoxicity. In conclusion, WA improves GalN/LPS-induced hepatotoxicity by targeting macrophage partially dependent on NLRP3 antagonism, while largely independent of NRF2 signaling, autophagy induction, and hepatic AMPKα1 and IκκB. These results support the concept of treating FH by pharmacologically targeting macrophage and suggest that WA has the potential to be repurposed for clinically treating FH as an immunoregulator.

Protective effects of mild hypothermia against hepatic injury in rats with acute liver failure

INTRODUCTION AND OBJECTIVES

Acute liver failure (ALF) is a severe disease which is associated with a high mortality rate. As mild hypothermia has been shown to have protective effects on the brain, this study aimed to determine whether it also provides protection to the liver in rats with ALF and to explore its underlying mechanism.

MATERIALS AND METHODS

In total, 72 rats were divided into 3 groups: control group (CG, treated with normal saline), normothermia group (NG, treated with d-galactosamine and lipopolysaccharide; d-GalN/LPS), and mild hypothermia group (MHG, treated with d-GalN/LPS and kept in a state of mild hypothermia, defined as an anal temperature of 32-35°C). The rats were examined at 4, 8, and 12h after treatment.

RESULTS

Mild hypothermia treatment significantly reduced serum alanine transaminase and aspartate transaminase levels and improved the liver condition of rats with d-GalN/LPS-induced ALF at 12h. Serum tumor necrosis factor-alpha levels were significantly lower in the MHG than in the NG at 4h, but no significant differences were observed in the interleukin-10 levels between the NG and MHG at any time. The serum and hepatic levels of high mobility group box 1 were significantly lower in the MHG than in the NG at 8 and 12h. The protein expression levels of cytochrome C and cleaved-caspase 3 in hepatic tissues were significantly lower in the MHG than in the NG at 8h.

CONCLUSION

Mild hypothermia improved the liver conditions of rats with ALF via its anti-inflammatory and anti-apoptotic effects.

The improvement effect of gastrodin on LPS/GalN-induced fulminant hepatitis via inhibiting inflammation and apoptosis and restoring autophagy

Fulminant hepatitis (FH), characterized by overwhelmed inflammation and massive hepatocyte apoptosis, is a life-threatening and high mortality rate. Gastrodin (GTD), a phenolic glucoside extracted from Gastrodiaelata Blume, exerts anti-apoptosis, and anti-inflammatory activities. In the present study, we aimed to evaluate whether GTD treatment could alleviate lipopolysaccharide and d-galactosamine (LPS/GalN)-induced FH in mice and its potential mechanisms. These data suggested that GTD treatment remarkably protected against LPS/GalN-induced FH by enhancing the survival rate of mice, reducing ALT and AST levels, attenuating histopathological changes, and suppressing interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α secretion. In addition, GTD treatment relieved hepatic apoptosis by the regulation of peroxisome proliferator-activated receptors (PPARs), P53 and caspase-3/9. Furthermore, GTD treatment could significantly inhibit inflammation-related signaling pathways activated by LPS/GalN, including the suppression of nucleotide-binding domain (NOD)-like receptor protein 3 (NLRP3) and nuclear factor-kappa B (NF-κB) activation. Importantly, GTD treatment effectively restored but not induced LPS/GalN-reduced the expression of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) phosphorylation, as well as the level of pro-autophagy proteins. Taken together, our investigation indicated that GTD played an essential role in liver protection by relieving hepatocyte apoptosis and inflammation reaction, which may be closely involved in the inhibition of NLRP3 inflammasome and NF-κB activation, regulation of apoptosis-related proteins expression, and the recovery of AMPK/ACC/autophagy.

Can hypothyroidism be a protective factor for hepatocellular carcinoma in cirrhosis?

Despite many studies, the molecular mechanisms of hepatocellular carcinoma (HCC) development remain unclear. Thyroid hormone (TH) levels may vary in many chronic diseases including cirrhosis. The aim of this study was to evaluate TH status in patients with cirrhosis and HCC and to investigate the relationship between THs and HCC development.Five hundred seventy-seven patients with cirrhosis who applied to Demiroğlu Bilim University, Faculty of Medicine, Gastroenterology Department between 2004 and 2019 were included the study. Three hundred sixty-seven patients who applied to Internal Medicine Unit for general health check-up were included in the study as healthy control group. Demographic, laboratory, and imaging findings of study groups were retrospectively reviewed and recorded from hospital information system.In the cirrhosis group, 252 patients had HCC (43.67%), and 325 patients had non-HCC cirrhosis (56.33%). Free thyroxine (FT4) levels were higher in the control group than in the cirrhotic group but there was no significant difference (P = .501). Thyroid-stimulating hormone (TSH) and FT4 levels were similar between groups, while free triiodothyronine (FT3) levels were significantly different between HCC group, non-HCC cirrhosis group, and control group (P = .299 for TSH, P = .263 for FT4, P < .001 for FT3). FT3 levels were significantly higher in HCC group than non-HCC cirrhosis group, but significantly lower than control group (P < .05).Our study confirmed the presence of hypothyroidism in cirrhosis patients and clearly demonstrated a strong relationship between FT3 levels and HCC development.

Protective effects of a novel water-soluble biphenyl compound WLP-S-14 against acute-on-chronic liver failure in rats

This study investigated the therapeutic effects of a water-soluble biphenyl compound, WLP-S-14, in acute-on-chronic liver failure (ACLF). Wistar rats were injected intraperitoneally with porcine serum twice a week for 8 weeks prior to administration of 600 mg/kg D-galactosamine and 50 μg/kg lipopolysaccharide to induce ACLF. Study groups were treated intravenously with saline or with 100 or 200 mg/kg WLP-S-14. WLP-S-14 ameliorated ACLF with significant reductions in the mortality rate and transaminase levels, indicating improved liver function. The mechanism underlying these effects may involve decreased levels of tumor necrosis factor-α and interleukin-6, with associated inhibition of apoptotic pathways.

Engeletin inhibits Lipopolysaccharide/d-galactosamine-induced liver injury in mice through activating PPAR-γ

Liver injury is a serious clinical syndrome that characterized by inflammatory response. Engeletin is known to have anti-inflammatory activity. However, the effects of engeletin on liver injury remain unclear. We aimed to assess the protective effect of engeletin on Lipopolysaccharide (LPS)/d-galactosamine (D-gal)-induced liver injury in mice. Engeletin was administered intraperitoneally 1 h before and 12 h after LPS/D-gal treatment. The results showed that engeletin treatment on LPS/D-gal-induced liver injury in mice have a significant protective effect, as confirmed by the attenuation of liver histopathologic changes, MPO activity, and serum AST and ALT levels. At the meanwhile, it also showed that engeletin inhibited the levels of IL-β and TNF-α in serum and liver tissues. Besides, engeletin blocked the activation of NF-κB induced by LPS/D-gal and induced the expression of PPAR-γ in a dose-dependently manner. These findings suggested that engeletin may have a protective effect against liver injury.

The Effects of Urtica dioica and Lamium album Extracts on the Expression Level of Cyclooxygenase-2 and Caspase-3 in the Liver and Kidney of Streptozotocin-Induced Diabetic Rats

Background: Diabetes seems to be associated with increased inflammation and induced apoptosis in several tissues. Urtica dioica and Lamium album have shown to possess a variety of beneficial properties like anti-inflammatory effects. In this experimental study, we tried to evaluate the effects of U. dioica and L. album extracts on the expression level of cyclooxygenase-2 (COX-2; as an inflammation marker) and caspase-3 (CASP-3; as an apoptotic marker) in the liver and kidney tissues of diabetic rats. Methods: Thirty-two male Wistar rats were randomly allocated to four groups: normal control, diabetic control, diabetic treated with U. dioica (100 mg/kg/daily), and diabetic treated with L. album (100 mg/kg/daily) for 28 days. At the end of the study, liver and kidney tissues were harvested and mRNA expression level of COX-2 and CASP-3 was determined by real-time PCR technique. Also, serum glucose was measured. Results: Liver COX-2 mRNA in diabetic rats was significantly higher than normal control rats (P=0.02). However, U. dioica and L. album caused significant decrease in mRNA expression of liver COX-2 in diabetic rats (P=0.015 and P=0.03, respectively). Also, in diabetic rats treated with both extracts, serum glucose was remarkably lower than diabetic control rats (P<0.0001 and P<0.01, respectively). Conclusion: It appears that U. dioica and L. album might decrease liver damage by decreasing the inflammatory effects of COX-2 in streptozocin-induced diabetic rats. Since these plant extracts may influence diabetes by several mechanisms, further research in this field is warranted.

Inflammation and pancreatic cancer: An updated review

Pancreatic cancer is a devastating disease with poor prognosis in the modern era. Inflammatory processes have emerged as key mediators of pancreatic cancer development and progression. Recently, studies have been carried out to investigate the underlying mechanisms that contribute to tumorigenesis induced by inflammation. In this review, the role of inflammation in the initiation and progression of pancreatic cancer is discussed.

TNF-α-TNFR signal pathway inhibits autophagy and promotes apoptosis of alveolar macrophages in coal worker's pneumoconiosis

OBJECTIVE

Exposure to coal dust causes the development of coal worker's pneumoconiosis (CWP), which is associated with accumulating macrophages in the lower respiratory tract. This study was performed to investigate the effect of tumor necrosis factor-α (TNF-α)-tumor necrosis factor receptor (TNFR) signal pathway on autophagy and apoptosis of alveolar macrophages (AMs) in CWP.

METHODS

AMs from controls exposed to coal dust and CWP patients were collected, in which expressions of TNF-α and TNFR1 were determined. Autophagy was observed by transmission electron microscopy, and apoptosis by light microscope and using terminal deoxynucleotidyl transferase dUTP nick-end labeling staining. AMs in CWP patients were treated with TNF-α or anti-TNF-α antibody. Besides, expressions of autophagy marker proteins, apoptosis-related factors, FAS, caspase-8, and receptor-interacting serine-threonine-protein kinase 3 (RIPK3) were determined by western Blot. Activities of caspase-3 and caspase-8 were determined by a fluorescence kit. Flow cytometry was applied to measure the expression of TNFR1 on the surface of the AM.

RESULTS

TNF-α expression and TNFR1 expression on the surface of AM, as well as autophagy and apoptotic index were significantly increased in AMs of CWP patients. In response to the treatment of TNF-α, TNF-α expression and TNFR1 expression on the surface of AM as well as LC3I expression were increased, autophagy was decreased, and LC3, LC3II, Beclin1 and B-cell lymphoma 2 expressions decreased, whereas FAS expression and activity and expression of caspase-3 and caspase-8 increased, and apoptotic index increased. Moreover, the situations were reversed with the treatment of anti-TNF-α antibody.

CONCLUSION

TNF-α-TNFR signal pathway was involved in the occurrence and development of CWP by activating FAS-caspase-8 and thus inhibiting autophagy while promoting apoptosis of AM.

Cerebellar Upregulation of Cell Surface Death Receptor-Mediated Apoptotic Factors in Harmaline-Induced Tremor: An Immunohistochemistry Study

Active caspase-3-mediated apoptosis has been implicated in the pathogenesis of harmaline-induced tremor. The aim of this study is to illustrate the impact of tremor induction on the expression of factors mediating the cell surface death receptor–dependent apoptosis. A total of 20 normal Wistar rats were randomly selected and equally divided into control and experimental groups. Tremor was induced in the experimental group by injecting the rats with a single dose of harmaline (50 mg/kg). After that, cerebellar tissues were evaluated by immunohistochemistry to examine the expression of tumor necrosis factor α (TNF-α) and active caspase-8 in the 2 groups of animals. TNF-α and active caspase-8 expression was significantly higher in cerebella from experimental rats compared with that in those from the control rats (P value < .01). Thus, our present data suggest the association of tremor induction with the cerebellar overexpression of TNF-α and active caspase-8, correlative with Purkinje cell (PC) loss indicated by loss of calbindin immunoreactivity, indicating the induction of the cell surface death receptor–mediated apoptosis.

Selenium deficiency impaired structural integrity of the head kidney, spleen and skin in young grass carp (Ctenopharyngodon idella)

This study focused on the effects of dietary selenium deficiency on structural integrity of the head kidney, spleen and skin in young grass carp (Ctenopharyngodon idella). A total of 540 healthy grass carp (mean weight 226.48 ± 0.68 g) were randomly divided into six groups and fed six separate diets with graded dietary levels of selenium (0.025-1.049 mg/kg diet) for 80 days. Results showed that selenium deficiency (1) caused oxidative damage in part by reducing the activities of antioxidant enzymes (such as SOD, CAT, GPx, GST and GR) and glutathione (GSH) content, down-regulating the transcript abundances of antioxidant enzymes (except GSTp1) partly related to Kelch-like-ECH-associated protein 1a (Keap1a)/NF-E2-related factor 2 (Nrf2) signalling; (2) aggravated apoptosis in part by up-regulating the mRNA levels of caspase-2, -3, -7, -8 and -9, which were partially related to p38MAPK/FasL/caspase-8 signalling and JNK/(BAX, Bcl-2, Mcl-1b, IAP)/(Apaf1, caspase-9) signalling; (3) damaged the tight junctions in part by down-regulating the mRNA levels of ZO-1 (except spleen), ZO-2 (except spleen), claudin-c, -f, -7, -11 and claudin-15, and up-regulating the mRNA levels of claudin-12, which were partially related to myosin light chain kinase (MLCK) signalling. Interesting, selenium deficiency failed to affect the expression of GSTp1, Keap1a, occludin, claudin-b, claudin-3c, ZO-1 (spleen only) and ZO-2 (spleen only) in the head kidney, spleen and skin of grass carp. Finally, based on the activities of glutathione peroxidase (GPx) and reactive oxygen species (ROS) content in the head kidney, spleen and skin, the dietary selenium requirements for young grass carp were estimated to be 0.558-0.588 mg/kg diet.

Galactosylated chitosan triptolide nanoparticles for overcoming hepatocellular carcinoma: Enhanced therapeutic efficacy, low toxicity, and validated network regulatory mechanisms

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related deaths worldwide. Current therapies present significant limitations. Triptolide (TP) is highly effective against multiple cancers including HCC. However, high toxicity, low water solubility, and unknown therapeutic targets limit its clinical application. Herein, we designed galactosylated-chitosan-TP-nanoparticles (GC-TP-NPs) with high drug loading capacities for targeted delivery to HCC. In addition to a sustained release pattern, an efficient asialoglycoprotein receptor mediated cellular uptake in vitro, and high liver tumor accumulation in vivo, GC-TP-NPs showed lower systemic and male reproductive toxicities than free TP. Importantly, GC-TP-NPs retained the anti-cancer activities of the free TP, exerting the same pro-apoptotic and anti-proliferative effects on HCC cells in vitro, and displayed higher efficacies in reducing tumor sizes in vivo. Further investigation revealed that GC-TP-NPs induced cancer cell apoptosis via blocking TNF/NF-κB/BCL2 signaling. Collectively, GC-TP-NP represents a promising candidate in halting liver cancer progression while minimizing systemic toxicity.

Loss of PDK4 switches the hepatic NF-κB/TNF pathway from pro-survival to pro-apoptosis

It has been established that nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) members promote survival by upregulating antiapoptotic genes and that genetic and pharmacological inhibition of NF-κB is required for tumor necrosis factor (TNF)-induced hepatocyte apoptosis. In this study, we demonstrate that this pro-survival pathway is switched to pro-apoptosis under pyruvate dehydrogenase kinase 4 (PDK4)-deficient conditions. PDK4-deficiency triggered hepatic apoptosis concomitantly with increased numbers of aberrant mitochondria, reactive oxygen species (ROS) production, sustained c-Jun N-terminal Kinase (JNK) activation, and reduction of glutathione (GSH). Interestingly, PDK4 retained p65 in cytoplasm via a direct protein-protein interaction. Disruption of PDK4-p65 association promoted p65 nuclear translocation. This, in turn, facilitated p65 binding to the TNF promoter to activate TNF-TNFR1 apoptotic pathway. Pdk4^-/- livers were sensitized to Jo2 and D-(+)-Galactosamine /Lipopolysaccharide (GalN/LPS)-mediated apoptotic injury which was prevented by the inhibition of p65 or TNFR1. The pro-survival activity of TNF was shifted, which was switched to a pro-apoptotic activity in Pdk4^-/- hepatocytes as a result of impaired activation of pro-survival NF-κB targets. Conclusion: PDK4 is indispensable to dictate the fate of TNF/NF-κB-mediated hepatocyte apoptosis. (Hepatology 2018).

Dopamine alleviated acute liver injury induced by lipopolysaccharide/d-galactosamine in mice

Dopamine (DA), a crucial neurotransmitter, not only functions in the central nervous system but also plays important roles in the modulation of inflammation. Several studies suggest that DA might suppress the inflammatory response both in vitro and in vivo. In the present study, the potential effects of DA in a mouse model with lipopolysaccharide (LPS)/d-galactosamine (D-Gal)-induced acute liver injury were investigated. The results show that DA-treated LPS/D-Gal-exposed mice had reduced incidence of histologic lesions, lower plasma aminotransferases and improved the survival rates compared to LPS/D-Gal-exposed mice. Treatment with DA also suppressed LPS/D-Gal-induced production of TNF-α, phosphorylation of c-jun-N-terminal kinase (JNK), cleavage of caspase-3, up-regulation of hepatic caspase-3, caspase-8, and caspase-9 activities and reduced the count of TUNEL-positive hepatocytes. These data indicate that DA attenuated LPS/D-Gal-induced fulminant liver injury in mice, which implies that DA might have value for the prevention of inflammatory liver disease.

Maslinic acid protects against lipopolysaccharide/d-galactosamine-induced acute liver injury in mice

Acute liver injury is a life-threatening syndrome that often caused by hepatocyte damage. In this study, we investigated the protective effects of maslinic acid (MA) on lipopolysaccharide (LPS)/d-galactosamine (D-gal)-induced acute liver injury and clarified its mechanism. Mice acute liver injury model was induced by given LPS and D-gal and MA was given intraperitoneally 1 h before LPS and D-gal. Our results showed that MA protected against liver injury by attenuating liver histopathologic changes, serum AST and ALT levels. The increased inflammatory cytokines TNF-α and IL-6 in serum and liver tissues were also inhibited by MA. The level of MDA and the activity of MPO in liver tissues were up-regulated by LPS/D-gal and dose-dependently inhibited by MA. Furthermore, MA attenuated hepatic NF-κB protein expression and increased hepatic Nrf2 and HO-1 protein expression. Taken together, MA offers a protective role against LPS/D-gal-induced liver injury through suppressing NF-κB and activating Nrf2 signaling pathways.

Isovitexin alleviates liver injury induced by lipopolysaccharide/d-galactosamine by activating Nrf2 and inhibiting NF-κB activation

The aim of this study was to investigate the protective effects and mechanism of isovitexin, a glycosylflavonoid isolated from rice hulls of Oryza sativa, on Lipopolysaccharide (LPS)/d-galactosamine (D-Gal)-induced acute liver injury. The mice were randomly divided into five groups: control group, LPS/D-Gal group, and LPS/D-Gal + isovitexin groups. The mice of LPS/D-Gal group were received of LPS (50 μg/kg) and D-gal (800 mg/kg) intraperitoneal. The mice of LPS/D-Gal + isovitexin groups were received isovitexin (25, 50, 100 mg/kg) 1 h before LPS/D-Gal treatment. The results showed that the severity of liver injury was attenuated by treatment of isovitexin, as confirmed by the decreased liver histopathologic changes, as well as serum AST and ALT levels. Furthermore, the levels of TNF-α in serum and liver tissues, MPO activity and MDA content were significantly inhibited by isovitexin. In addition, isovitexin significantly attenuated NF-κB phosphorylation induced by LPS/D-Gal. The expression of Nrf2 and HO-1 were significantly up-regulated by isovitexin. In conclusion, isovitexin could protect against LPS/D-Gal-induced liver injury by inhibiting inflammatory and oxidative responses. Isovitexin also had protective effects against carbon tetrachloride (CCl₄)-induced liver injury. Isovitexin may used as a potential agent for the treatment of liver injury.

Protective effects and immunomodulation on piglets infected with rotavirus following resveratrol supplementation

Rotavirus (RV), belonging to Reoviridae family, is the leading cause of acute severe viral diarrhea in children (under 5 years old) and infant animals worldwide. Although vaccines are commonly used to prevent infection, episodes of diarrhea caused by RV frequently occur. Thus, this study was conducted to determine whether resveratrol had protective effects against RV infection in piglets. Following pretreatment with resveratrol dry suspension through adding into the basal diet for 3 weeks, the piglets were orally challenged with RV. We found that resveratrol could alleviate diarrhea induced by RV infection. Resveratrol-treatment inhibited the TNF-α production, indicating that the anti-RV activity of resveratrol may be achieved by reducing the inflammatory response. The IFN-γ level was elevated in 10mg/kg/d resveratrol-treated group and 30mg/kg/d resveratrol-treated group after RV infection. The ratios of CD4+/CD8+ in resveratrol-treated groups were the same as that in mock infected group, suggesting that resveratrol could maintain the immune function in RV-infected piglets. It was found that resveratrol could alleviate diarrhea induced by RV infection. These results revealed that resveratrol dry suspension could be a new control measure for RV infection.

The Receptor Interacting Protein Kinases in the Liver

The receptor interacting serine/threonine kinase1 and 3 (RIPK1, RIPK3) are regulators of cell death and survival. RIPK1 kinase activity is required for necroptosis and apoptosis, while its scaffolding function is necessary for survival. Although both proteins can mediate apoptosis, RIPK1 and RIPK3 are most well-known for their role in the execution of necroptosis via the mixed lineage domain like pseudokinase. Necroptosis is a caspase-independent regulated cell death program which was first described in cultured cells with unknown physiologic relevance in the liver. Many recent reports have suggested that RIPK1 and/or RIPK3 participate in liver disease pathogenesis and cell death. Notably, both proteins have been shown to mediate inflammation independent of cell death. Whether necroptosis occurs in hepatocytes, and how it is executed in the presence of an intact caspase machinery is controversial. In spite of this controversy, it is evident that RIPK1 and RIPK3 participate in many experimental liver disease models. Therefore, in addition to cell death signaling, their necroptosis-independent role warrants further examination.

Hepatic neuregulin 4 signaling defines an endocrine checkpoint for steatosis-to-NASH progression

Nonalcoholic steatohepatitis (NASH) is characterized by progressive liver injury, inflammation, and fibrosis; however, the mechanisms that govern the transition from hepatic steatosis, which is relatively benign, to NASH remain poorly defined. Neuregulin 4 (Nrg4) is an adipose tissue-enriched endocrine factor that elicits beneficial metabolic effects in obesity. Here, we show that Nrg4 is a key component of an endocrine checkpoint that preserves hepatocyte health and counters diet-induced NASH in mice. Nrg4 deficiency accelerated liver injury, fibrosis, inflammation, and cell death in a mouse model of NASH. In contrast, transgenic expression of Nrg4 in adipose tissue alleviated diet-induced NASH. Nrg4 attenuated hepatocyte death in a cell-autonomous manner by blocking ubiquitination and proteasomal degradation of c-FLIPL, a negative regulator of cell death. Adeno-associated virus-mediated (AAV-mediated) rescue of hepatic c-FLIPL expression in Nrg4-deficent mice functionally restored the brake for steatosis to NASH transition. Thus, hepatic Nrg4 signaling serves as an endocrine checkpoint for steatosis-to-NASH progression by activating a cytoprotective pathway to counter stress-induced liver injury.

HIMH0021 attenuates ethanol-induced liver injury and steatosis in mice

Chronic alcohol consumption causes alcohol-induced lipogenesis and promotes hepatic injury by preventing the oxidation of hepatocellular fatty acids through the suppression of the activation of AMP-activated protein kinase (AMPK). HIMH0021, an active flavonoid compound, which is a component of the Acer tegmentosum extract, has been shown to protect against liver damage caused by alcohol consumption. Therefore, in this study, we aimed to determine whether HIMH0021 could regulate alcoholic fatty liver and liver injury in mice. Oral administration of 10 days of Lieber-DeCarli ethanol plus a single binge of 30% ethanol (chronic-plus-binge model) induced steatosis and liver injury and inflammation in mice, which appears similar to the condition observed in human patients with alcohol-related diseases. HIMH0021, which was isolated from the active methanol extract of A. tegmentosum, inhibited alcohol-induced steatosis and attenuated the serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) during hepatocellular alcohol metabolism, both of which promote lipogenesis as well as liver inflammation. Treatment with HIMH0021 conferred protection against lipogenesis and liver injury, inhibited the expression of cytochrome P4502E1, and increased serum adiponectin levels in the mice subjected to chronic-plus-binge feeding. Furthermore, in hepatocytes, HIMH0021 activated fatty acid oxidation by activating pAMPK, which comprises pACC and CPT1a. These findings suggested that HIMH0021 could be used to target a TNFα-related pathway for treating patients with alcoholic hepatitis.

Oridonin ameliorates lipopolysaccharide/D-galactosamine-induced acute liver injury in mice via inhibition of apoptosis

We investigated the protective effects exerted by oridonin, the main active constituent of the Chinese medicinal herb Rabdosiarubescens, against lipopolysaccharide (LPS)/D-galactosamine (D-Gal)-induced acute liver injury (ALI). An ALI model was induced in mice using LPS (40 μg/0.5 ml) and D-Gal (5 mg/0.5 ml). The mice were randomly divided into the following five groups of six mice each: one control group (a), one ALI group (b), two oridonin treatment groups (c and d), and one oridonin control group (e). Oridonin (0.2 mg/0.5 ml) was administered once 1 h prior to the LPS/D-Gal challenge in group c and a total of three times over a period of four days, with the last dose given at 1 h before the LPS/D-Gal challenge, in group d. Pretreatment with oridonin improved the survival rate, alleviated histopathological abnormalities, and suppressed plasma aminotransferases in the LPS/D-Gal-challenged mice. Importantly, oridonin attenuated LPS/D-Gal-induced apoptosis in hepatocytes by reducing pro-apoptotic signals (P<0.05), such as tumor necrosis factor-α (TNF-α) and c-Jun N-terminal kinases (JNK). Furthermore, JNK-associated mitochondrial pro-apoptotic proteins were also suppressed by pretreatment with oridonin. Taken together, these data show that oridonin exerts protective effects against LPS/D-Gal-induced ALI in mice via a mechanism that may involve the suppression of the pro-apoptotic cytokine TNF-α and JNK-associated pro-apoptotic signaling.