IL-22 ameliorates LPS-induced acute liver injury by autophagy activation through ATF4-ATG7 signaling

Abstract Uncontrollable inflammatory response acts as a driver of sepsis-associated liver injury (SALI). IL-22 plays an important role in regulating inflammatory responses, but its role in SALI remains unknown. The aim of the study was to assess the association of serum IL-22 with SALI in pediatric patients and to enclose the underlying mechanisms of IL-22 involved in lipopolysaccharide (LPS) - induced acute liver injury (ALI) in mice. Serum IL-22 levels in patients with SALI were significantly lower than in septic patients without liver injury, and the area under receiver operating characteristic (ROC) curve of IL-22 for discriminating SALI was 0.765 (95% CI: 0.593–0.937). Pre-administration of recombinant murine IL-22 alleviated LPS-induced ALI in mice, and serum IL-6 levels and the mRNA levels of TNF-α, IL-1β, and IL-6 in livers were decreased in response to IL-22 pre-treatment in mice. More importantly, IL-22 pre-treatment activated hepatic autophagy mediated by activating transcription factor 4 (ATF4)-autophagy-related gene 7 (ATG7) signaling in vivo and in vitro in response to LPS administration. Moreover, knockdown of ATF4 in mice aggravated LPS-induced ALI, which was associated with suppressed ATG7-related autophagy. In addition, the protective effects of IL-22 on LPS-induced ALI was partially blocked by ATF4 knockdown, which was associated with lower expression of LC3II/I in the livers of ATF4 knockdown (HT or Atf4+/−) mice compared with wild-type mice (WT or Atf4+/+) mice. In conclusion, low serum IL-22 level is associated with SALI occurrence, and IL-22 pre-administration activates autophagy in hepatocytes and protects mice against LPS-induced ALI partially related to ATF4-ATG7 signaling pathway.

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Protective Effect of Eckol against Acute Hepatic Injury Induced by Carbon Tetrachloride in Mice

Marine Drugs ◽

10.3390/md16090300 ◽

2018 ◽

Vol 16 (9) ◽

pp. 300 ◽

Cited By ~ 8

Author(s):

Shulan Li ◽

Juan Liu ◽

Mengya Zhang ◽

Yuan Chen ◽

Tianxing Zhu ◽

...

Keyword(s):

Carbon Tetrachloride ◽

Liver Injury ◽

Protective Effect ◽

Acute Liver Injury ◽

Treated Group ◽

Terminal Deoxynucleotidyl Transferase ◽

Enhanced Expression ◽

Pre Treatment

Several in vitro studies have shown the potential hepatoprotective properties of eckol, a natural phlorotannin derived from the brown alga. However, the in vivo hepatoprotective potential of eckol has not been determined. In this study, we performed an in vivo study to investigate the protective effect of eckol and its possible mechanisms on the carbon tetrachloride (CCl4)-induced acute liver injury model in mice. Results revealed that eckol pre-treatment at the dose of 0.5 and 1.0 mg/kg/day for 7 days significantly suppressed the CCl4-induced increases of alanine transaminase (ALT) and aspartate aminotransferase (AST) levels in serum and meliorated morphological liver injury. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling (TUNEL) analysis showed that the number of positive apoptotic hepatocytes in the eckol-treated group was lower than that in the CCl4 model group. Western blotting analysis also demonstrated the enhanced expression of bcl-2 and suppressed expression of cleaved caspase-3 by eckol. The CCl4-induced oxidative stress in liver was significantly ameliorated by eckol, which was characterized by reduced malondialdehyde (MDA) formations, and enhanced superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) activities and glutathione (GSH) content. Moreover, the CCl4-induced elevations of pro-inflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6 were markedly suppressed in the eckol-treated group. However, eckol enhanced the level of IL-10, a potent anti-inflammatory cytokine, and recruited CD11c+ dendritic cells into the liver tissues of CCl4-treated mice. These results indicated that eckol has the protective effect on CCl4-induced acute liver injury via multiple mechanisms including anti-apoptosis, anti-oxidation, anti-inflammation and immune regulation.

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Evaluation of [18F]F-DPA as a target for TSPO in head and neck cancer under normal conditions and after radiotherapy

European Journal of Nuclear Medicine and Molecular Imaging ◽

10.1007/s00259-020-05115-z ◽

2020 ◽

Author(s):

Sanni Tuominen ◽

Thomas Keller ◽

Nataliia Petruk ◽

Francisco López-Picón ◽

Dominik Eichin ◽

...

Keyword(s):

Head And Neck ◽

Inflammatory Responses ◽

Ex Vivo ◽

Mrna Levels ◽

Malignant Tumours ◽

Pre Treatment ◽

Induced Changes ◽

Tspo Expression

Abstract Background Many malignant tumours have increased TSPO expression, which has been related to a poor prognosis. TSPO-PET tracers have not comprehensively been evaluated in peripherally located tumours. This study aimed to evaluate whether N,N-diethyl-2-(2-(4-([18F]fluoro)phenyl)-5,7-dimethylpyrazolo[1,5-a]pyrimidin-3-yl)acetamide ([18F]F-DPA) can reflect radiotherapy (RT)-induced changes in TSPO activity in head and neck squamous cell carcinoma (HNSCC). Methods RT was used to induce inflammatory responses in HNSCC xenografts and cells. [18F]F-DPA uptake was measured in vivo in non-irradiated and irradiated tumours, followed by ex vivo biodistribution, autoradiography, and radiometabolite analysis. In vitro studies were performed in parental and TSPO-silenced (TSPO siRNA) cells. TSPO protein and mRNA expression, as well as tumour-associated macrophages (TAMs), were also assessed. Results In vivo imaging and ex vivo measurement revealed significantly higher [18F]F-DPA uptake in irradiated, compared to non-irradiated tumours. In vitro labelling studies with cells confirmed this finding, whereas no effect of RT on [18F]F-DPA uptake was detected in TSPO siRNA cells. Radiometabolite analysis showed that the amount of unchanged [18F]F-DPA in tumours was 95%, also after irradiation. PK11195 pre-treatment reduced the tumour-to-blood ratio of [18F]F-DPA by 73% in xenografts and by 88% in cells. TSPO protein and mRNA levels increased after RT, but were highly variable. The proportion of M1/M2 TAMs decreased after RT, whereas the proportion of monocytes and migratory monocytes/macrophages increased. Conclusions [18F]F-DPA can detect changes in TSPO expression levels after RT in HNSCC, which does not seem to reflect inflammation. Further studies are however needed to clarify the physiological mechanisms regulated by TSPO after RT.

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Azithromycin ameliorates sulfur dioxide-induced airway epithelial damage and inflammatory responses

Respiratory Research ◽

10.1186/s12931-020-01489-8 ◽

2020 ◽

Vol 21 (1) ◽

Author(s):

Jon Petur Joelsson ◽

Jennifer A. Kricker ◽

Ari J. Arason ◽

Snaevar Sigurdsson ◽

Bryndis Valdimarsdottir ◽

...

Keyword(s):

Sulfur Dioxide ◽

Airway Epithelium ◽

Inflammatory Responses ◽

Protein Composition ◽

Lavage Fluid ◽

Protective Effects ◽

Barrier Dysfunction ◽

Pre Treatment

Abstract Background The airway epithelium (AE) forms the first line of defence against harmful particles and pathogens. Barrier failure of the airway epithelium contributes to exacerbations of a range of lung diseases that are commonly treated with Azithromycin (AZM). In addition to its anti-bacterial function, AZM has immunomodulatory effects which are proposed to contribute to its clinical effectiveness. In vitro studies have shown the AE barrier-enhancing effects of AZM. The aim of this study was to analyze whether AE damage caused by inhalation of sulfur dioxide (SO2) in a murine model could be reduced by pre-treatment with AZM. Methods The leakiness of the AE barrier was evaluated after SO2 exposure by measuring levels of human serum albumin (HSA) in bronchoalveolar lavage fluid (BALF). Protein composition in BALF was also assessed and lung tissues were evaluated across treatments using histology and gene expression analysis. Results AZM pre-treatment (2 mg/kg p.o. 5 times/week for 2 weeks) resulted in reduced glutathione-S-transferases in BALF of SO2 injured mice compared to control (without AZM treatment). AZM treated mice had increased intracellular vacuolization including lamellar bodies and a reduction in epithelial shedding after injury in addition to a dampened SO2-induced inflammatory response. Conclusions Using a mouse model of AE barrier dysfunction we provide evidence for the protective effects of AZM in vivo, possibly through stabilizing the intracellular microenvironment and reducing inflammatory responses. Our data provide insight into the mechanisms contributing to the efficacy of AZM in the treatment of airway diseases.

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Pterostilbene Reduces Acetaminophen-Induced Liver Injury by Activating the Nrf2 Antioxidative Defense System via the AMPK/Akt/GSK3β Pathway

Cellular Physiology and Biochemistry ◽

10.1159/000493655 ◽

2018 ◽

Vol 49 (5) ◽

pp. 1943-1958 ◽

Cited By ~ 13

Author(s):

Xiaoye Fan ◽

Lidong Wang ◽

Jingbo Huang ◽

Hongming Lv ◽

Xuming Deng ◽

...

Keyword(s):

Liver Injury ◽

Hepg2 Cells ◽

Glycogen Synthase ◽

Heme Oxygenase 1 ◽

Related Factor ◽

Protective Effects ◽

Cytochrome C Release ◽

Underlying Mechanisms

Background/Aims: Pterostilbene (Pts), a natural dimethylated analog of resveratrol from blueberries, exerts antioxidative and anti-apoptotic effects in various diseases. This study aims to investigate the protective effects and mechanism of Pts against acetaminophen (APAP)-induced hepatotoxicity in vivo. Methods: C57BL/6 mice were treated with APAP or APAP+Pts. HepG2 cells were used to further explore the underlying mechanisms in vitro. The effects of Pts on hepatotoxicity were measured by commercial kits, Hematoxylin and Eosin (H&E) straining, TUNEL assay, Western blot analysis, and Flow cytometry assay. Results: In vivo, Pts treatment effectively protected against APAP-induced severe liver injury by decreasing the lethality rate, the serum alanine transaminase (ALT) and aspartate aminotransferase (AST) levels, liver histological injury, liver malondialdehyde (MDA) formation and myeloperoxidase (MPO) levels and by increasing liver glutathione (GSH) and superoxide dismutase (SOD) levels. Moreover, in Pts-treated mice, the nuclear factor-erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway was activated; however, APAP-induced c-Jun NH2-terminal kinase (JNK) activation, mitochondrial Bcl-2 Associated X Protein (Bax) translocation, apoptosis-inducing factor (AIF) levels and cytochrome c release were attenuated. In vitro, Pts was found to reverse hydrogen peroxide (H2O2) -induced cytotoxicity, reactive oxygen species (ROS) production and apoptosis that depended on Nrf2 activation. Moreover, Pts induced a dose-dependent increase in the phosphorylation of AMP-activated protein kinase (AMPK), serine/threonine kinase (Akt), and glycogen synthase kinase 3β (GSK3β) in HepG2 cells. Moreover, Pts protect against APAP or H2O2-induced toxicity were effectively attenuated or abolished in HepG2 Nrf2-/- cells and Nrf2-/- mice. Conclusion: Our data suggest that Pts protects against APAP-induced toxicity by activating Nrf2 via the AMPK/Akt/GSK3β pathway.

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Lemon Balm and Dandelion Leaf Extracts Synergistically Protect against Carbon Tetrachloride-Induced Acute Liver Injury in Mice

Applied Sciences ◽

10.3390/app11010390 ◽

2021 ◽

Vol 11 (1) ◽

pp. 390

Author(s):

Beom-Rak Choi ◽

Il-Je Cho ◽

Su-Jin Jung ◽

Jae-Kwang Kim ◽

Dae-Geon Lee ◽

...

Keyword(s):

Carbon Tetrachloride ◽

Liver Injury ◽

Acute Liver Injury ◽

Antioxidant Activities ◽

Body Weight Gain ◽

Histopathological Analysis ◽

Related Factor ◽

Mrna Levels ◽

Protective Effects ◽

Lemon Balm

Lemon balm and dandelion are commonly used medicinal herbs exhibiting numerous pharmacological activities that are beneficial for human health. In this study, we explored the protective effects of a 2:1 (w/w) mixture of lemon balm and dandelion extracts (MLD) on carbon tetrachloride (CCl4)-induced acute liver injury in mice. CCl4 (0.5 mL/kg; i.p.) injection inhibited body weight gain and increased relative liver weight. Pre-administration of MLD (50–200 mg/kg) for 7 days prevented these CCl4-mediated changes. In addition, histopathological analysis revealed that MLD synergistically alleviated CCl4-mediated hepatocyte degeneration and infiltration of inflammatory cells. MLD decreased serum aspartate aminotransferase and alanine transferase activities and reduced the number of liver cells that stained positive for cleaved caspase-3 and cleaved poly(ADP-ribose) polymerase, suggesting that MLD protects against CCl4-induced hepatic damage via the inhibition of apoptosis. Moreover, MLD attenuated CCl4-mediated lipid peroxidation and protein nitrosylation by restoring impaired hepatic nuclear factor erythroid 2-related factor 2 mRNA levels and its dependent antioxidant activities. Furthermore, MLD synergistically decreased mRNA and protein levels of tumor necrosis factor-α, interleukin-1β, and interleukin-6 in the liver. Together, these results suggest that MLD has potential for preventing acute liver injury by inhibiting apoptosis, oxidative stress, and inflammation.

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5-O-Demethylnobiletin Alleviates CCl4-Induced Acute Liver Injury by Equilibrating ROS-Mediated Apoptosis and Autophagy Induction

International Journal of Molecular Sciences ◽

10.3390/ijms22031083 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1083

Author(s):

Sukkum Ngullie Chang ◽

Se Ho Kim ◽

Debasish Kumar Dey ◽

Seon Min Park ◽

Omaima Nasif ◽

...

Keyword(s):

Liver Injury ◽

Acute Liver Injury ◽

Elevated Serum ◽

In Vitro Study ◽

Biological Properties ◽

Autophagic Flux ◽

Serum Aminotransferase ◽

Ccl4 Treatment

Polymethoxyflavanoids (PMFs) have exhibited a vast array of therapeutic biological properties. 5-O-Demethylnobiletin (5-DN) is one such PMF having anti-inflammatory activity, yet its role in hepatoprotection has not been studied before. Results from in vitro study revealed that 5-DN did not exert a high level of cytotoxicity on HepG2 cells at 40 μM, and it was able to rescue HepG2 cell death induced by carbon tetrachloride (CCl4). Subsequently, we investigated acute liver injury on BALB/c mice induced by CCl4 through the intraperitoneal injection of 1 mL/kg CCl4 and co-administration of 5-DN at (1 and 2 mg/kg) by oral gavage for 15 days. The results illustrated that treatment with 5-DN attenuated CCl4-induced elevated serum aminotransferase (AST)/alanine aminotransferase (ALT) ratio and significantly ameliorated severe hepatic damage such as inflammation and fibrosis evidenced through lesser aberrations in the liver histology of 5-DN dose groups. Additionally, 5-DN efficiently counteracted and equilibrated the production of ROS accelerated by CCl4 and dramatically downregulated the expression of CYP2E1 vitally involved in converting CCl4 to toxic free radicals and also enhanced the antioxidant enzymes. 5-DN treatment also inhibited cell proliferation and inflammatory pathway abnormally regulated by CCl4 treatment. Furthermore, the apoptotic response induced by CCl4 treatment was remarkably reduced by enhanced Bcl-2 expression and noticeable reduction in Bax, Bid, cleaved caspase 3, caspase 9, and apaf-1 expression. 5-DN treatment also induced the conversion of LC3 and promoted the autophagic flux. Conclusively, 5-DN exhibited hepatoprotective effects in vitro and in vivo and prevented liver fibrosis induced by CCl4.

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Mechanism of KLF4 Protection against Acute Liver Injury via Inhibition of Apelin Signaling

Oxidative Medicine and Cellular Longevity ◽

10.1155/2019/6140360 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Weitao Ji ◽

Hongyun Shi ◽

Hailin Shen ◽

Jing Kong ◽

Jiayi Song ◽

...

Keyword(s):

Liver Injury ◽

Signaling Pathway ◽

Acute Liver Injury ◽

Control Group ◽

Necrosis Factor Alpha ◽

Protein Levels ◽

Klf4 Expression ◽

Mrna And Protein Expression

Krüppel-like factor 4 (KLF4) is a key transcription factor that regulates genes involved in the proliferation or differentiation in different tissues. Apelin plays roles in cardiovascular functions, metabolic disease, and homeostatic disorder. However, the biological function of apelin in liver disease is still ongoing. In this study, we investigated the mechanism of KLF4-mediated protection against acute liver injury via the inhibition of the apelin signaling pathway. Mice were intraperitoneally injected with carbon tetrachloride (CCl4; 0.2 mL dissolved in 100 mL olive oil, 10 mL/kg) to establish an acute liver injury model. A KLF4 expression plasmid was injected through the tail vein 48 h before CCl4 treatment. In cultured LX-2 cells, pAd-KLF4 or siRNA KLF4 was overexpressed or knockdown, and the mRNA and protein levels of apelin were determined. The results showed that the apelin serum level in the CCl4-injected group was higher than that of control group, and the expression of apelin in the liver tissues was elevated while KLF4 expression was decreased in the CCl4-injected group compared to the KLF4-plasmid-injected group. HE staining revealed serious hepatocellular steatosis in the CCl4-injected mice, and KLF4 alleviated this steatosis in the mice injected with KLF4 plasmid. In vitro experiments showed that tumor necrosis factor-alpha (TNF-α) could downregulate the transcription and translation levels of apelin in LX-2 cells and also upregulate KLF4 mRNA and protein expression. RT-PCR and Western blotting showed that the overexpression of KLF4 markedly decreased basal apelin expression, but knockdown of KLF4 restored apelin expression in TNF-α-treated LX-2 cells. These in vivo and in vitro experiments suggest that KLF4 plays a key role in inhibiting hepatocellular steatosis in acute liver injury, and that its mechanism might be the inhibition of the apelin signaling pathway.

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Ginsenoside Rb1, A Major Saponin from Panax ginseng, Exerts Protective Effects Against Acetaminophen-Induced Hepatotoxicity in Mice

The American Journal of Chinese Medicine ◽

10.1142/s0192415x19500927 ◽

2019 ◽

Vol 47 (08) ◽

pp. 1815-1831 ◽

Cited By ~ 4

Author(s):

Shen Ren ◽

Jing Leng ◽

Xing-Yue Xu ◽

Shuang Jiang ◽

Ying-Ping Wang ◽

...

Keyword(s):

Liver Injury ◽

Panax Ginseng ◽

Inflammatory Responses ◽

Interleukin 1 ◽

Protective Effects ◽

Ginsenoside Rb1 ◽

Drug Induced ◽

Drug Induced Liver Injury ◽

Oxide Synthase

Acute liver injury (ALI) induced by acetaminophen (APAP) is the main cause of drug-induced liver injury. Previous reports indicated liver failure could be alleviated by saponins (ginsenosides) from Panax ginseng against APAP-induced inflammatory responses in vivo. However, validation towards ginsenoside Rb1 as a major and marker saponin may protect liver from APAP-induced ALI and its mechanisms are poorly elucidated. In this study, the protective effects and the latent mechanisms of Rb1 action against APAP-induced hepatotoxicity were investigated. Rb1 was administered orally with 10[Formula: see text]mg/kg and 20[Formula: see text]mg/kg daily for 1 week before a single injection of APAP (250[Formula: see text]mg/kg, i.p.) 1[Formula: see text]h after the last treatment of Rb1. Serum alanine/aspartate aminotransferases (ALT/AST), liver glutathione (GSH) depletion, as well as the inflammatory cytokines, such as tumor necrosis factor-[Formula: see text] (TNF-[Formula: see text]), interleukin-1[Formula: see text] (IL-1[Formula: see text]), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2), were analyzed to indicate the underlying protective effects of Rb1 against APAP-induced hepatotoxicity with significant inflammatory responses. Histological examination further proved Rb1’s protective effects. Importantly, Rb1 mitigated the changes in the phosphorylation of MAPK and PI3K/Akt, as well as its downstream factor NF-[Formula: see text]B. In conclusion, experimental data clearly demonstrated that Rb1 exhibited a remarkable liver protective effect against APAP-induced ALI, partly through regulating MAPK and PI3K/Akt signaling pathways-mediated inflammatory responses.

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circ-CBFB upregulates p66Shc to perturb mitochondrial dynamics in APAP-induced liver injury

Cell Death and Disease ◽

10.1038/s41419-020-03160-y ◽

2020 ◽

Vol 11 (11) ◽

Author(s):

Zhecheng Wang ◽

Yan Zhao ◽

Ruimin Sun ◽

Yu Sun ◽

Deshun Liu ◽

...

Keyword(s):

Liver Injury ◽

Mitochondrial Dynamics ◽

Circular Rna ◽

Protective Effects ◽

Bioinformatics Analyses ◽

Hepatocyte Injury ◽

Rna Immunoprecipitation ◽

Competitive Endogenous Rna

Abstract p66Shc, a master regulator of mitochondrial reactive oxygen species (mtROS), is a crucial mediator of hepatocyte oxidative stress. However, its functional contribution to acetaminophen (APAP)-induced liver injury and the mechanism by which it is modulated remain unknown. Here, we aimed to assess the effect of p66Shc on APAP-induced liver injury and to evaluate if circular RNA (circRNA) functions as a competitive endogenous RNA (ceRNA) to mediate p66Shc in APAP-induced liver injury. p66Shc-, miR-185-5p-, and circ-CBFB-silenced mice were injected with APAP. AML12 cells were transfected with p66Shc, miR-185-5p, and circ-CBFB silencing or overexpression plasmids or siRNAs prior to APAP stimulation. p66Shc was upregulated in liver tissues in response to APAP, and p66Shc silencing in vivo protected mice from APAP-induced mitochondrial dynamics perturbation and liver injury. p66Shc knockdown in vitro attenuated mitochondrial dynamics and APAP-induced hepatocyte injury. Mechanically, p66Shc perturbs mitochondrial dynamics partially by inhibiting OMA1 ubiquitination. miR-185-5p, which directly suppressed p66Shc translation, was identified by microarray and bioinformatics analyses, and its overexpression attenuated mitochondrial dynamics and hepatocyte injury in vitro. Furthermore, luciferase, pull-down and RNA immunoprecipitation assays demonstrated that circ-CBFB acts as a miRNA sponge of miR-185-5p to mediate p66Shc in APAP-induced liver injury. circ-CBFB knockdown also alleviated APAP-induced mitochondrial dynamics perturbation and hepatocyte injury. More importantly, we found that the protective effects of circ-CBFB knockdown on p66Shc, mitochondrial dynamics and liver injury were abolished by miR-185-5p inhibition both in vivo and in vitro. In conclusion, p66Shc is a key regulator of APAP-induced liver injury that acts by triggering mitochondrial dynamics perturbation. circ-CBFB functions as a ceRNA to regulate p66Shc during APAP-induced liver injury, which may provide a potential therapeutic target.

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