Immunological Liver Injury In Mice Research Articles

Jian Gan powder ameliorates immunological liver injury in mice by modulating the gut microbiota and metabolic profiles

BackgroundImmunological liver injury (ILI) is a common liver disease associated with the microbiota-gut-liver axis. Jian Gan powder (JGP) exhibits both protective and therapeutic effects on hepatitis virus-induced ILI in the clinic. However, the underlying mechanisms remain elusive. The aim of this study is to investigate the hepatoprotective effects and associated mechanisms of JGP in the context of gut microbiota, utilizing a mouse model of ILI.MethodsThe mouse model was established employing Bacillus Calmette-Guérin (BCG) plus lipopolysaccharide (LPS). Following treatment with JGP (7.5, 15, or 30 g/kg), serum, liver, and fresh fecal samples were analyzed. 16S rRNA gene sequencing and untargeted metabolomics profiling were performed to assess the role of JGP on the gut microbiota and its metabolites.ResultsJGP treatment markedly reduced serum IFN-γ, IL-6, IL-22, and hepatic p-STAT3 (phosphorylated transducer and activator of transcription-3) expression. In contrast, JGP increased the percentage of proliferating cell nuclear antigen-positive liver cells in treated mice. Fecal 16S rRNA gene sequencing revealed that JGP treatment restored the levels of Alloprevotella, Burkholderia-Caballeronia-Paraburkholderia, Muribaculum, Streptococcus, and Stenotrophomonas. Additionally, metabolomics analysis of fecal samples showed that JGP restored the levels of allylestrenol, eplerenone, phosphatidylethanolamine (PE) (P-20:0/0:0), sphingomyelin (SM) d27:1, soyasapogenol C, chrysin, and soyasaponin I.ConclusionsJGP intervention improves ILI by restoring gut microbiota and modifying its metabolic profiles. These results provide a novel insight into the mechanism of JGP in treating ILI and the scientific basis to support its clinical application.

Monocyte-derived macrophages contribute to the deterioration of immunological liver injury in mice

Background & aimsAutoimmune hepatitis (AIH) is characterized by hepatocyte destruction, leading to lymphocyte and macrophage accumulation in the liver. However, the specific mechanisms of how macrophages participate in the occurrence and development of AIH are still unclear. In this study, we investigated the effect of monocyte-derived macrophages on Con A-induced immunological liver injury in mice and we hypothesized that inhibition of CCR2 with the dual CCR2/5 inhibitor, cenicriviroc (CVC), would attenuate Con A-induced hepatitis in mice by reducing the recruitment of monocytes into the liver. MethodsMurine experimental AIH was established by concanavalin A (Con A) injection intravenously. Macrophages were depleted by injection of clodronate liposomes in Con A-treated mice. Moreover, inhibition of the CCR2/5 signaling pathway in Con A mice is achieved by CVC. Liver injury and infiltration of monocyte-derived macrophages were assessed by serum transaminase levels, histopathology, immunohistochemistry, flow cytometry, RT–qPCR, ELISA, TUNEL assay and dihydroethidium staining. ResultsThe number of macrophages in the mouse livers increased in the Con A-induced hepatitis mouse model, and flow cytometry showed a significant increase in the proportion of F4/80loCD11bhi monocyte-derived macrophages, while there was no significant change in the proportion of F4/80hiCD11blo Kupffer cells. After the depletion of liver macrophages by clodronate liposomes, the levels of serum ALT and AST, and the degree of liver tissue damage were alleviated in Con A-treated mice. Furthermore, Con A leaded an increase in the expression of a group of CC chemokines in mouse livers, and the elevation of CCL2 was prevented with the depletion of macrophages. Additionally, CVC reduced macrophage infiltration in the liver and ameliorated Con A-induced liver injury. Meanwhile, CVC reduced the apoptosis and oxidative damage of hepatocytes caused by Con A. ConclusionsOur research demonstrates that there is an increase in monocyte-derived macrophages in the livers due to the monocyte infiltration resulted from the activation of the CCL2-CCR2 axis in Con A-induced liver injury mouse model. Pharmacological inhibition of CCR2 monocyte recruitment by CVC efficiently ameliorates the hepatic inflammation, indicating the therapeutic potential of CVC in patients with AIH.

Ethyl Acetate Extract from Artemisia argyi Prevents Liver Damage in ConA-Induced Immunological Liver Injury Mice via Bax/Bcl-2 and TLR4/MyD88/NF-κB Signaling Pathways.

Immunological liver injury (ILI) is a common liver disease and lacks potent drugs for treatment. Artemisia argyi Lévl. et Vant. (A. argyi), a medicinal and edible homologous plant usually used in diet therapy to cure various liver diseases, provides a great option for the prevention of ILI. To investigate the effect that ethyl acetate extract of A. argyi (AaEA) on Concanavalin A (ConA)-induced ILI and the mechanism of regulating Bax/Bcl-2 and TLR4/MyD88/NF-κB signaling pathways. The chemical components of AaEA were studied by LC-MS. In animal experiments, the positive control group was administrated diammonium glycyrrhizinate (DIG, 100 mg/kg), while different doses of AaEA groups (AaEA-H, AaEA-M, AaEA-L) were pretreated with AaEA 2.00, 1.00, and 0.50 g/kg, respectively, by intragastric for seven days, once every day. Then, ConA (12.00 mg/kg) was used through tail intravenous injection to establish the ILI model. The blood samples and livers were collected to test the degree of liver dysfunction, inflammation, oxidative stress, histopathological changes, and cell apoptosis. Real-time PCR and Western blotting analysis were used to explain the mechanism of regulating Bax/Bcl-2 and TLR4/MyD88/NF-κB signaling pathways. The way in which AaEA prevents liver damage in immunological liver injury (ILI) mice caused by ConA was investigated for the first time. Pretreatment with AaEA reduced the expression of ALT, AST, and inflammatory factors (TNF-α and IFN-γ). Meanwhile, AaEA also reduced MDA levels but upregulated the contents of IL-4, SOD, and GSH-px, alleviating oxidative stress induced by ILI. Western blotting and real-time PCR analysis demonstrated that AaEA could regulate the expression level and relative mRNA expression of key proteins on Bax/Bcl-2 and TLR4/MyD88/NF-κB signaling pathways. Finally, 504 components from AaEA were identified by LC-MS analysis, mainly including flavones, phenolic acids, and terpenoids with anti-inflammatory and liver protective activities, which highlights the potential of AaEA for diet treatment of ILI. AaEA can work against ConA-induced ILI in mice by regulating Bax/Bcl-2 and TLR4/MyD88/NF-κB signaling pathways, which has the potential to be a great strategy for the prevention of ILI.

S-Propargyl-cysteine prevents concanavalin A-induced immunological liver injury in mice

Context S-Propargyl-cysteine (SPRC), an endogenous H2S modulator, exerts anti-inflammatory effects on cardiovascular and neurodegenerative disease, but it remains unknown whether SPRC can prevent autoimmune hepatitis. Objective To evaluate the preventive effect of SPRC on concanavalin A (Con A)-induced liver injury and uncover the underlying mechanisms. Materials and methods Mice were randomly divided into five groups: control, Con A, SPRC (5 and 10 mg/kg injected intravenously once a day for 7 days), and propargylglycine (PAG; 50 mg/kg injected intraperitoneally 0.5 h before SPRC for 7 days). All mice except the controls were intravenously injected with Con A (20 mg/kg) on day 7. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were evaluated using kits. Inflammatory cytokines (TNF-α and IFN-γ) in the blood and in the liver were detected by ELISA Kit and real-time PCR, respectively. The expression of mitogen-activated protein kinase (MAPK) pathway proteins (p-JNK and p-Akt) and apoptosis proteins (Bax and Bcl-2) was detected using western blotting. Results SPRC reduced the levels of AST (p < 0.05) and ALT (p < 0.01) and decreased the release of the inflammatory cytokines. Mechanistically, SPRC increased H2S level (p < 0.05) and promoted cystathionine γ-lyase (CSE) expression (p < 0.05). SPRC inhibited the MAPK pathway activation and the apoptosis pathway. All the effects of SPRC were blocked by the CSE inhibitor PAG. Conclusions SPRC prevents Con A-induced liver injury in mice by promoting CSE expression and producing endogenous H2S. The mechanisms include reducing the release of inflammatory cytokines, attenuating MAPK pathway activation, and alleviating apoptosis.

Metabolomics study on the therapeutic mechanism of Schisandra chinensis polysaccharides on concanavalin A-induced immunological liver injury in mice

Background: Schisandra chinensis is a traditional Chinese herbal medicine which protects hepatic function. Its primary component is polysaccharides which is used in the treatment of hepatic injury, but the mechanism of action of S. chinensis polysaccharides (SCP) in immunological liver injury induced by concavalin A (Con A) is still not clear. Aim: In this study, we aimed to evaluate the hepatoprotective mechanism of SCP in immunological liver injury. Subjects and Methods: In this study, we performed rapid-resolution liquid chromatography coupled with quadruple-time-of-flight mass spectrometry-based serum metabolomics approach to investigate the hepatoprotective effects of SCP against Con A-induced immunological liver injury in mice. Results: According to our results, SCP significantly increased the activity of superoxide dismutase in the liver; decreased the level of serum aspartate aminotransaminase (AST), serum alanine aminotransaminase (ALT), tumor necrosis factor-α, interferon-γ, interleukin (IL)-1 β, and IL-6 in the serum, and decreased the level of malondialdehyde and nitric oxide in the liver of mice with immunological liver injury induced by Con A. In this study, we identified 17 biomarkers through metabolomic analysis, and after the administration of SCP, 16 of them were found to return to the normal levels. Our analysis suggested that some metabolic pathways are involved in the mechanisms of action of SCP for the treatment of the immunological liver injury, including energy metabolism, amino acid metabolism, taurine metabolism, amino saccharide and nucleotide metabolism, arachidonic acid metabolism, and lipid metabolism. Conclusion: SCP could alleviate the oxidative stress and inflammatory reaction in the immunological liver injury and recover the metabolic dysfunction caused by Con A.

Magnesium isoglycyrrhizinate ameliorates concanavalin A-induced liver injury via the p38 and JNK MAPK pathway

Context Acute liver failure is a serious disease caused by a variety of factors, and immunological injury is an important pathological process. Comprehensive liver treatment efficacy is poor, and the mortality rate is high. Magnesium isoglycyrrhizinate (MgIG) is a new glycyrrhizin drug extracted from the traditional Chinese medicine licorice. The mechanism by which MgIG regulates ConcanavalinA (ConA)-induced immunological liver injury in mice is not completely clear. Materials and methods Immunological liver injury was induced in mice by ConA injection, and the inflammatory macrophages model was induced by lipopolysaccharide (LPS). MgIG was administered 30 min prior to ConA and LPS treatment. The mice in the different groups were sacrificed 12 h after treatment, and macrophages were measured at 30 min, 1 h, and 2 h after induction. Macrophages, liver, and blood samples were then collected for analysis. Results After drug administration, the MgIG group showed a marked decrease in serum transaminase levels, reduced apoptosis and hepatic inflammatory responses compared to the ConA group. Furthermore, there was a significant reduction in inflammatory cytokine levels in the serum and liver tissue. In vitro, the expression of inflammatory cytokines was distinctly reduced after MgIG administration. In addition, MgIG pretreatment reduced the expression of inflammatory cytokines and regulated the phosphorylation of p38 and JNK proteins in the MAPK pathway. Conclusion These findings demonstrated that MgIG protects against ConA-induced immunological liver injury by markedly alleviating liver inflammation, and this provides guidance for the clinical amelioration of liver inflammation induced by immunological factors.

Glycyrrhizic acid ammonium salt alleviates Concanavalin A-induced immunological liver injury in mice through the regulation of the balance of immune cells and the inhibition of hepatocyte apoptosis

Glycyrrhizic acid ammonium salt (GAAS) is derived from glycyrrhizic acid, which is an active compound extracted from the Chinese traditional medicine licorice. GAAS is clinically applied to treat immune-mediated liver injury, but its mechanism remains elusive. Therefore, this study aimed to investigate the mechanism in which GAAS alleviates immune-mediated liver injury induced by Concanavalin A (ConA). After ten days of intragastric administration of GAAS, 20 mg/kg ConA was injected via tail vein to establish the immune-mediated liver injury model of BALB/C mice. Then, the concentrations of ALT, AST, and TBIL in the serum of mice were determined. H&E staining was performed to observe the pathological changes in the liver, and the expression of liver cytokines was detected by qPCR. Immunohistochemistry and Western blot analysis was employed to detect the expression of liver-related proteins. The apoptosis in liver tissue was detected by TUNEL. Our results suggest that GAAS demonstrated excellent protective effects in the liver. We found that GAAS down-regulated the mRNA expression of IL-1β, IL-6, TNF-α, IFN-γ, and IL-17A, and it up-regulated the mRNA expression of IL-4 and TGF-β. Additionally, GAAS may modulate the balance of four immune cells (Th1, Th2, Th17, and Treg) by regulating the expression of T-bet, GATA3, RORγt, and Foxp3 to alleviate liver injury in mice. Furthermore, GAAS decreased hepatocyte apoptosis by blocking the JAK1/STAT1/IRF1 pathway, suppressing oxidative stress, decreasing p-JNK expression, and regulating the expression of apoptosis-related proteins. In summary, the mechanism of GAAS in liver injury alleviation acts to regulate the balance of Th cells in the liver to inhibit hepatocyte apoptosis. This study may provide a new strategy for the treatment of immune-mediated liver injury.

Magnesium isoglycyrrhizinate protects against concanavalin A-induced immunological liver injury in a mouse model

Abstract Background: To evaluate the protective effects of magnesium isoglycyrrhizinate on a mouse model of concanavalin A (ConA)-induced immunological liver injury. Materials and Methods: Forty-eight mice were randomly divided into a normal control group, a model group, three dose groups of magnesium isoglycyrrhizinate (12.5, 25, 50 mg/kg) and a dexamethasone group (2.5 mg/kg). Magnesium isoglycyrrhizinate was intraperitoneally injected for 5 consecutive days, and the model of immunological liver injury was established on the fifth day after caudal vein injection of ConA (20 mg/kg). Blood was collected to detect the activities of alanine transaminase (ALT) and aspartate transaminase (AST) as well as the levels of tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ). The levels of neopterin (NP) and malondialdehyde (MDA) and the activities of myeloperoxidase (MPO) and superoxide dismutase (SOD) in liver tissues were measured, and histopathological changes were observed. Results: The serum levels of ALT and AST in the model group increased. Hepatic lobules had necrotic foci and inflammatory cell infiltration. The plasma levels of TNF-α and IFN-γ increased. In liver tissues, the levels of NP, MDA and MPO rose, but that of SOD decreased. Magnesium isoglycyrrhizinate significantly attenuated the activities of ALT and AST (P&lt;0.05). Histopathological staining showed that inflammation of the liver was relieved significantly. Magnesium isoglycyrrhizinate also decreased the levels of NP, MDA and MPO in liver tissues (P&lt;0.05), raised that of SOD and reduced the plasma levels of TNF-α and IFN-γ (P&lt;0.05). Conclusion: Magnesium isoglycyrrhizinate protected against ConA-induced immunological liver injury in mice, probably through immune regulation and antioxidation.

Hepatoprotective effect of apple polyphenols against concanavalin A-induced immunological liver injury in mice

Apple polyphenols (AP), a polyphenol extracted from the unripe apple, has been reported to improve acute hepatotoxicity induced by CCl4 in mice due to its significant antioxidant activity. In this study, the hepatoprotective effect of AP against concanavalin A (Con A)-induced immunological liver injury in mice was investigated. Mice were treated with AP daily for seven days prior to a single intravenous administration of Con A. The serum levels of AST, ALT, TP, Alb and histopathological changes were determined and the A/G ratio was calculated. Potential mechanisms were further explored by measuring TNF-α and IFN-γ levels, NO content as well as changes in the levels of endogenous oxidants and antioxidants. AP significantly improved the abnormal levels of ALT, AST, TP and Alb, and the A/G ratio. AP was also associated with improvement of liver histopathological changes after Con A-induced liver injury. Moreover, AP reduced serum levels of TNF-α and IFN-γ, decreased serum NO content, inhibited oxidative DNA single-strand breaks, and improved the abnormalities of MDA content, SOD activity and GSH level. These results suggest that AP exerts a protective effect against Con A-induced immunological liver injury through suppressing pro-inflammatory cytokines and activating the antioxidant system.

Inhibition of Sophocarpine on Poly I: C/D-GalN-Induced Immunological Liver Injury in Mice

Increasing evidence has suggested that natural killer (NK) cells contribute to the pathogenesis of human immunological liver injury (ILI). Previous studies have demonstrated that Sophocarpine exerts activity in immune modulation. It also has a therapeutic effect on liver protection in that it can alleviate liver fibrosis by suppressing both the activation of hepatic stellate cells and the proliferation of the activated hepatic stellate cells. However, whether Sophocarpine protects the liver by regulating NK cell activity remains unclear. In this study, the modulating effect of Sophocarpine on NK cells in the liver was investigated. The results showed that Sophocarpine dramatically decreased the production of pro-inflammatory cytokines and attenuated the liver injury induced by Poly I: C/D-GalN in C57BL/6- mice. More importantly, Sophocarpine pre-treatment significantly suppressed NK cell activation and downregulated the expression of NKG2D, a receptor responsible for NK cell activation. Moreover, the protein levels of DAP12, ZAP76 and Syk decreased, as did their corresponding mRNA levels. Overall, our study demonstrates that Sophocarpine inhibits NK cell activity, thus making it a promising therapy for ILI.

Hepatoprotective activities of a sesquiterpene-rich fraction from the aerial part of Cichorium glandulosum

BackgroundCichorium glandulosum Boiss. et Huet is used for treatment of liver disorders, and its effects are attributed to sesquiterpenes. This study aims to investigate the hepatoprotective effects of a sesquiterpene-rich fraction (SRF) from the aerial part of C. glandulosum on carbon tetrachloride (CCl4)-induced acute hepatotoxicity in mice, and on priming with Bacillus Calmette–Guerin (BCG) followed by lipopolysaccharide (LPS)-induced immunological liver injury in mice.MethodsSRF was suspended in water and administered to mice at 0.05, 0.10 and 0.20 g/kg body weight for 7 consecutive days. An active control drug (bifendate pills) was suspended in distilled water and administered to mice at 0.40 g/kg body weight for 7 consecutive days. Hepatotoxicity was induced by intraperitoneal injection of 0.1% CCl4 (0.2 mL/mouse) at 13 h before the last drug administration, or by tail intravenous injection of BCG (0.2 mL/mouse) before the first drug administration and LPS (0.2 mL/mouse; 8 μg) at 15 h before the last drug administration. Blood samples and the livers were collected for evaluation of the biochemical parameters of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and total bilirubin (TBIL).ResultsSRF significantly reduced the impact of CCl4 toxicity. The highest dose of SRF (0.20 g/kg) was the most effective, reflected by significant reductions in the levels of AST (P = 0.001), ALT (P = 0.000) and TBIL (P = 0.009). The serum enzymatic levels induced by BCG and subsequent LPS injection were significantly and dose-dependently restored by SRF, reflected by significant reductions in the levels of AST (P = 0.003), ALT (P = 0.003) and TBIL (P = 0.007) for the highest dose of SRF (0.20 g/kg).ConclusionSRF is hepatoprotective in animal models of chemical and immunological acute liver injury.

Protective effect of atractylenolide I on immunological liver injury

To study the protective effect of atractylenolide I on immunological liver injury induced by BCG and LPS. Kunming mice were randomly divided into 6 groups: the normal group, the model group, positive control biphenyl group, the atractylenolide I high does group, the atractylenolide I middle dose group and the atractylenolide I low dose group (60, 120, 240 mg x kg(-1)), with 12 mice in each group. Immunological liver injury in mice was induced by BCG and LPS to compared liver index and spleen index and detect content of serum ALT, AST, MDA and GSH-px in serum and NO, iNOS, TNF-alpha in serum and liver homogenate. Liver pathological changes were observed by HE staining. Both of atractylenolide I and biphenyl remarkably decrease the increased live index and spleen index (P < 0.05), improve the histopathological changes in liver and pathological grades of liver tissues and relieve the inflammatory reaction induced by BCG and LPS. They showed a notable effect in improving MDA and GSH-px in serum. Atractylenolide I can obviously protect immunological injury liver a dose-dependent manner within the range of test doses. Its mechanism may be related to release or over expression of inhibitory inflammatory medium such as NO, iNOS and TNF-alpha.

Hepatoprotective Effects of Total Triterpenoids and Total Flavonoids from Vitis vinifera L against Immunological Liver Injury in Mice.

Suosuo grape (the fruits of Vitis vinifera L) has been used for prevention and treatment of liver diseases in Uighur folk medicine in China besides its edible value. In this study, the hepatoprotective effects of total triterpenoids (VTT) and total flavonoids (VTF) from Suosuo grape were evaluated in Bacille-Calmette-Guerin- (BCG-) plus-lipopolysaccharide- (LPS-) induced immunological liver injury (ILI) in mice. Various dose groups (50, 150, and 300 mg/kg) of VTT and VTF alleviated the degree of liver injury of ILI mice, effectively reduced the BCG/LPS-induced elevated liver index and spleen index, hepatic nitric oxide (NO), and malondialdehyde (MDA) content, increased liver homogenate alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, and restored hepatic superoxide dismutase (SOD) activity in ILI mice. VTT and VTF also significantly inhibited intrahepatic expression of Th1 cytokines (IFN-γ and IL-2) in ILI mice and increased intrahepatic expression of Th2 cytokines (IL-4 and IL-10). Moreover, the increased Bax/Bcl-2 ratio was significantly downregulated by VTT and VTF in liver tissue of ILI mice. These results are comparable to those of biphenyl dicarboxylate (DDB, the reference hepatoprotective agent) and suggest that VTT and VTF play a protective role against immunological liver injury, which may have important implications for our understanding of the immunoregulatory mechanisms of this plant.

Protective effects of IL-4 on Bacillus Calmette-Guerin and lipopolysaccharide induced immunological liver injury in mice

Mice injected with Bacillus Calmette-Guérin (BCG) were challenged with lipopolysaccharide (LPS) to induce inflammatory liver injury. This study was performed to explore the protective effects of interleukin (IL)-4 against liver injury induced by BCG and LPS in mice. Mice injected with BCG (125mg/kg) were challenged with LPS (10μg/kg) to induce the model of inflammatory liver injury. Half an hour after injection of LPS, mice were subcutaneously administered rmIL-4 at 5 and 0.5μg/kg, respectively. Liver injury was evaluated by serum transaminase assay and H & E staining. Liver cytokine concentrations were determined by enzyme-linked immunosorbent assay, and intrahepatic cytokine and iNOS mRNA levels by reverse transcriptase polymerase chain reaction. Intrahepatic apoptosis was evaluated by terminal deoxynucleotidyl transferase mediated nick end labeling. NF-κB p65 and ERK signal pathway was detected by Western-blotting. NF-κB signal pathway was also detected by electrophoretic mobility shift assay. IL-4 reduced the serum ALT, AST and LDH, alleviated the inflammatory cells infiltration, down regulated the expression of TNF-α, IL-1β, IFN-γ, IL-6 and iNOS mRNA in liver, and alleviated hepatic glutathione depletion (GSH). In addition, IL-4 displayed inhibition of extracellular signal-regulated kinase phosphorylation and NF-κB activation. IL-4 may protect mice against BCG/LPS-induced immune liver injury, besides ERK and NF-κB signal pathways were involved in the effects.

Paeoniflorin improves survival in LPS-challenged mice through the suppression of TNF-α and IL-1β release and augmentation of IL-10 production

Lipopolysaccharide (LPS) plays an important role in Gram-negative bacteria-induced sepsis and multiple organ dysfunction syndrome, which are still the leading cause of high mortality in intensive care units. Although paeoniflorin (Pae) has reportedly exhibited anti-inflammatory effect and protection against immunological liver injury in mice, it is not known whether Pae improve survival in endotoxemic mice. The purpose of this study was to determine the effect of Pae on the mortality, multiple organ dysfunction and cytokine production in lipopolysaccharide (LPS)-treated mice. We found that pretreatment with Pae decreased mortality, reduced lung and kidney injury, decreased serum creatinine level and improve systolic function of heart in mice challenged with LPS. Further experiments showed that Pae inhibited LPS-stimulated tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) release and promoted LPS-induced interleukin-10 (IL-10) production. Our results indicate that Pae protects mice against lethal LPS challenge, at least in part, through inhibiting TNF-α and IL-1β production and accelerating IL-10 expression.

Effect of magnesium isoglycyrrhizinate on concanavalin A (Con A)-induced immunological liver injury in mice

异甘草酸镁是第四代甘草酸制剂,其有效成分是一种高纯度单-18-α异构体甘草酸,临床主要用于治疗肝炎.通过抗炎、保护肝细胞膜及改善肝功能的药理作用,对四氯化碳、D-氨基半乳糖等引起的化学性肝损伤模型发挥保护效应[1-2].但目的鲜见对免疫性肝损伤作用的报道,因此,本实验通过建立刀豆蛋白A(ConA)诱导的小鼠免疫性肝损伤模型,进一步探讨异甘草酸镁的疗效及部分作用机制。

Protective Effect of Extract from Paeonia lactiflora and Astragalus membranaceus against Liver Injury Induced by Bacillus Calmette‐Guérin and Lipopolysaccharide in Mice

Paeonia lactiflora and Astragalus membranaceus are two popular traditional Chinese medicines, commonly used in Chinese herb prescription to treat liver disease. The extract from the roots of P. lactiflora and A. membranaceus demonstrated better hepatoprotective activity than the herbs used individually as shown in our previous studies. The present study was carried out to investigate the effects of P. lactiflora and A. membranaceus extract on immunological liver injury in mice induced by Bacillus Calmette-Guérin and lipopolysaccharide (BCG/LPS) and to explore a possible mechanism. After administration of P. lactiflora and A. membranaceus (60, 120 and 240 mg/kg, intragastrically) daily for 10 days, the extract significantly reduced the degree of liver damage in BCG/LPS-induced liver injury, as well as the elevation of serum transaminase activities and level of nitric oxide in live injury mice. The extract also restored the decrease in superoxide dismutase and glutathione peroxidase activities and inhibited the formation of lipid peroxidative products. Moreover, P. lactiflora and A. membranaceus (60, 120 and 240 mg/kg, intragastrically) repressed high levels of tumour necrosis factor-alpha (TNF-alpha) and interleukin-1 (IL-1) from peritoneal macrophages. In the primary cultured Kupffer cells, P. lactiflora and A. membranaceus also significantly decreased the production of TNF-alpha and IL-1 in cells stimulated with LPS (5 microg/ml). These results suggest that P. lactiflora and A. membranaceus have a protective effect on BCG/LPS-induced liver injury mice, which might be associated with the antioxidant properties, ability to reduce nitric oxide production and suppression of Kupffer cell activity and pro-inflammatory mediator and cytokines production.

Protection of a polysaccharide from Salvia miltiorrhiza, a Chinese medicinal herb, against immunological liver injury in mice

This study was designed to evaluate the hepatoprotective effects of S. miltiorrhiza polysaccharides (SMPS) in immunological liver injury induced by Bacille–Calmette–Guerin (BCG) and lipopolysaccharide (LPS) in mice. SMPS effectively improved the liver index, spleen index and thymus index, reduced the serum levels of alanine aminotransferase, aspartate aminotransferase and nitric oxide, and restored liver homogenate contents of tumor necrosis factor-α and interleukin-1β. The histopathological analysis suggested that SMPS reduced the degree of liver injury. The results suggest that SMPS play a protective role against immunological liver injury, which may have important implications for our understanding on the immunoregulatory mechanisms of polysaccharides.

PROTECTIVE EFFECT OF PAEONIFLORIN ON IMMUNOLOGICAL LIVER INJURY INDUCED BY BACILLUS CALMETTE‐GUERIN PLUS LIPOPOLYSACCHARIDE: MODULATION OF TUMOUR NECROSIS FACTOR‐α AND INTERLEUKIN‐6 mRNA

1. Paeoniflorin is one of the main effective components of the total glucosides of paeony (TGP) extracted from the root of Paeonia lactiflora which has been used for gynaecological problems and for cramp, pain and giddiness for over 1,500 years in Chinese medicine. Anti-inflammatory, antioxidative, antihepatic injury and immunoregulatory activities of TGP have been extensively proved in our laboratory for many years. Our present study investigates the effects and mechanisms of paeoniflorin on immunological liver injury in mice. 2. A model of immunological liver injury was induced by tail vein injection of bacillus Calmette-Guérin (BCG) and lipopolysaccharide (LPS) in mice. Activities of serum alanine aminotransferase (ALT) were measured by biochemical methods. Hepatic tissue sections were stained with haematoxylin and eosin and examined under a light microscope. Tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, lipopolysaccharide binding protein (LBP) and CD14 mRNA (messenger ribonucleic acid) expression in mouse liver were determined by semiquantitative reverse transcription polymerase chain reaction (RT-PCR) analysis. 3. Immunological liver injury induced by BCG plus LPS was successfully duplicated. Serum ALT activities were significantly decreased by paeoniflorin. (25, 50, 100 mg/kg). Histological examination demonstrated that paeoniflorin could attenuate the area and extent of necrosis and reduce the immigration of inflammatory cells. The increase in TNF-alpha, LBP and CD14 mRNA expression in mouse liver after BCG and LPS injection was significantly decreased by paeoniflorin (100 mg/kg) and was changed by paeoniflorin (25, 50 mg/kg) at different time-point. The augmentation of IL-6 mRNA in mouse liver was markedly increased by paeoniflorin at 1 h and 3 h after LPS injection. 4. Paeoniflorin could significantly protect against immunological liver injury in mice. TNF-alpha, IL-6, LBP and CD14 mRNA expression in mouse liver may be involved in BCG plus LPS induced liver injury. The protective mechanism of paeoniflorin might be partially related to modulation of TNF-alpha, IL-6, LBP and CD14 mRNA expressions in mouse liver.

A novel model of acute liver injury in mice induced by T cell-mediated immune response to lactosylated bovine serum albumin

The present study aimed to establish a murine liver injury model with T cell-mediated immune response to mimic the cellular immunological pathogenesis of hepatitis. Bovine serum albumin was conjugated with lactose by redox to prepare lactosylated bovine serum albumin (LacBSA). The liver injury was induced in C57BL/6 mice by a T cell-mediated immune response to LacBSA. After a systemic injection of LacBSA, which elicited immune response in mice sensitized twice with LacBSA, liver injury was observed with obvious increase of aminotransferase levels in serum and hepatocelluar damage in liver histology. However, the splenectomy before the elicitation significantly alleviated the liver injury. Direct contact between spleen T cells/nonparenchymal cells and hepatocytes was proved to be essential to induce the release of alanine aminotransferase in the culture supernatant. In addition, both levels of Fas mRNA in liver tissues and Fas Ligand in spleen cells were up-regulated at 6 h after the elicitation. The Fas mRNA expression was maintained in a relatively high level at 18 h while Fas Ligand began to decrease after 12 h. These results demonstrated that the T cell immune response to LacBSA could be successfully localized in the liver to induce an immunological liver injury in mice. The pathogenesis of the liver injury might involve the interaction between the liver-infiltrating lymphocytes and hepatocytes through Fas/FasL pathway.