Systemic inflammatory response syndrome in patients with severe fever with thrombocytopenia syndrome: prevalence, characteristics, and impact on prognosis.

BACKGROUND: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging zoonosis with a high fatality rate in China. Previous studies have reported that dysregulated inflammatory response is associated with disease pathogenesis and mortality in patients with SFTS. This investigation aimed to evaluate the prevalence and characteristics of systemic inflammatory response syndrome (SIRS), and its impact on prognosis. METHODS: Data on demographic characteristics, comorbid conditions, clinical manifestations, laboratory parameters, and survival time of patients with SFTS were collected. Patients were divided into the non-SIRS and SIRS groups according to the presence of SIRS, then their clinical data were compared. RESULTS: A total of 290 patients diagnosed with SFTS were retrospectively enrolled, including 126(43.4%) patients with SIRS. Patients in the non-survivor group had more prevalence of SIRS than patients in the survivor group (P < 0.001), and SIRS (adjusted OR 2.885, 95% CI 1.226-6.786; P = 0.005) was shown as an independent risk factor for prognosis of patients with SFTS. Compared with patients without SIRS, patients with SIRS had lower WBC and neutrophils counts, and fibrinogen levels, but higher AST, LDH, amylase, lipase, CK, CK-MB, troponin I, APTT, thrombin time, D-dimer, CRP, IL-6, SAA levels, and viral load. The cumulative survival rate of patients with SIRS was significantly lower than that of patients without SIRS. Patients with SIRS also showed a higher incidence of bacterial or fungal infections than patients without SIRS. CONCLUSIONS: SIRS is highly frequent in patients with SFTS, and it is associated with high mortality.

SIRT3 inhibitor 3-TYP exacerbates thioacetamide-induced hepatic injury in mice.

The purpose of the study was to explore the effects of SIRT3 inhibitor 3-TYP on acute liver failure (ALF) in mice and its underlying mechanism. The mice were treated with thioacetamide (TAA, 300 mg/kg) for inducing ALF model. 3-TYP (50 mg/kg) was administered 2 h prior to TAA. The liver histological changes were measured by HE staining. Blood samples were collected for analysis of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). MDA and GSH were used to evaluate the oxidative stress of liver. The expression levels of inflammatory cytokines (TNF-α and IL-1ß) were measured by ELISA and Western blotting. The cell type expression of IL-1ß in liver tissue was detected by immunofluorescent staining. The expression of SIRT3, MnSOD, ALDH2, MAPK, NF-κB, Nrf2/HO-1, p-elF2α/CHOP, and cleaved caspase 3 was determined by Western blotting. TUNEL staining was performed to detect the apoptosis cells of liver tissues. 3-TYP exacerbated the liver injury of ALF mice. 3-TYP increased the inflammatory responses and activation of MAPK and NF-κB pathways. In addition, 3-TYP administration enhanced the damage of oxidative stress, endoplasmic reticulum stress, and promoted hepatocyte apoptosis in ALF mice. 3-TYP exacerbates thioacetamide-induced hepatic injury in mice. Activation of SIRT3 could be a promising target for the treatment of ALF.

SIRT6 Activator UBCS039 Inhibits Thioacetamide-Induced Hepatic Injury In Vitro and In Vivo.

SIRT6 has been reported to have multiple functions in inflammation and metabolism. In the present study, we explored the regulatory effects and mechanisms of SIRT6 in thioacetamide (TAA)-induced mice acute liver failure (ALF) models. The SIRT6 activator UBCS039 was used in this animal and cell experiments. We observed that UBCS039 ameliorated liver damage, including inflammatory responses and oxidative stress. Further study of mechanisms showed that the upregulation of SIRT6 inhibited the inflammation reaction by suppressing the nuclear factor-κB (NF-κB) pathway in the TAA-induced ALF mice model and lipopolysaccharide-stimulated macrophages. In addition, the upregulation of SIRT6 alleviated oxidative stress damage in hepatocytes by regulating the Nrf2/HO-1 pathway. These findings demonstrate that pharmacologic activator of SIRT6 could be a promising target for ALF.

Role of SIRT1 in Hepatic Encephalopathy: In Vivo and In Vitro Studies Focusing on the NLRP3 Inflammasome.

Hepatic encephalopathy (HE) is a neuropsychiatric disorder resulting from acute or chronic liver failure. This study is aimed at investigating the therapeutic effects and mechanisms of SIRT1 in thioacetamide- (TAA-) induced rat HE models. A selective activator (CAY10602) and inhibitor (EX527) of SIRT1 were used in this study. All male rats were separated into control, TAA, CAY10602+TAA, and EX527+TAA groups. Histological damage, liver function, serum ammonia, behavioral changes, and brain oxidative stress were measured in each group. Western blotting was used to measure SIRT1, NLRP3, ASC, and IL-1ß protein expression. The results showed that CAY10602 alleviated liver injury, improved neurological decline, reduced microglial activation and brain oxidative stress, and improved the survival rates of HE rats. Moreover, CAY10602 inhibited activation of the NLRP3 inflammasome in microglia of the brain cortex in HE rats. Next, cell experiments confirmed that CAY10602 inhibited activation of the NLRP3 inflammasome in BV2 microglial cells. However, inhibition of SIRT1 by EX527 or lentivirus could enhance activation of the NLRP3 inflammasome in this process. Finally, CAY10602 reduced the neurotoxicity induced by high levels of ammonia in HT22 cells. Taken together, CAY10602 alleviates TAA-induced HE by suppressing microglial activation and the NLRP3 inflammasome and reducing the neurotoxicity of NH4Cl in HT22 cells. A pharmacologic activator of SIRT1 may be a promising approach for the treatment of HE.

Epigenetic Regulation of Hepatic Stellate Cell Activation and Macrophage in Chronic Liver Inflammation.

Chronic liver inflammation is a complex pathological process under different stress conditions, and the roles of stellate cells and macrophages in chronic liver inflammation have been widely reported. Moderate liver inflammation can protect the liver from damage and facilitate the recovery of liver injury. However, an inflammatory response that is too intense can result in massive death of hepatocytes, which leads to irreversible damage to the liver parenchyma. Epigenetic regulation plays a key part in liver inflammation. This study reviews the regulation of epigenetics on stellate cells and macrophages to explore the new mechanisms of epigenetics on liver inflammation and provide new ideas for the treatment of liver disease.

HDAC6 inhibitor ACY1215 inhibits the activation of NLRP3 inflammasome in acute liver failure by regulating the ATM/F-actin signalling pathway.

Acute liver failure (ALF) is a rare and critical medical condition. This study was designed to investigate the protective effects and underlying mechanism of ACY1215 in ALF mice. Our findings suggested that ACY1215 treatment ameliorates the pathological hepatic damage of ALF and decreases the serum levels of ALT and AST. Furthermore, ACY1215 pretreatment increased the level of ATM, γ-H2AX, Chk2, p53, p21, F-actin and vinculin in ALF. Moreover, ACY1215 inhibited the level of NLRP3, ASC, caspase-1, IL-1ß and IL-18 in ALF. The ATM inhibitor KU55933 could decrease the level of ATM, γ-H2AX, Chk2, p53, p21, F-actin and vinculin in ALF with ACY1215 pretreatment. The F-actin inhibitor cytochalasin B decreased the level of F-actin and vinculin in ALF with ACY1215 pretreatment. However, cytochalasin B had no effect on protein levels of ATM, Chk2, p53 and p21 in ALF with ACY1215 pretreatment. Cytochalasin B could dramatically increase the level of NLRP3, ASC, caspase-1, IL-1ß and IL-18 in ALF with ACY1215 pretreatment. These results indicated that ACY1215 exhibited hepatoprotective properties, which was associated with the inhibition of NLRP3 inflammasome, and this effect of ACY1215 was connected with upregulation of the ATM/F-actin mediated signalling pathways.

The relationship between liver pathological inflammation degree and pyroptosis in chronic hepatitis B patients.

The aim of this study is to explore the relationship between liver pathological inflammation degree and pyroptosis in patients with chronic hepatitis B (CHB). One hundred and twenty CHB patients' liver tissue samples, including A0-A3 inflammatory grades, were selected. Six tissue sections were selected for each indicator in each inflammation grade. The results of immunohistochemical analysis on the pyroptosis-related molecules (NLRP3, GSDMD, caspase1, interleukin [IL]-1ß, and IL-18) were determined. The correlation between the pyroptosis-related molecules and liver inflammatory activities was analyzed. The expression of NLRP3, GSDMD, caspase1, IL-18, and IL-1ß was respectively significantly positively correlated with the grade of inflammatory activity (r s = 0.690, p < 0.01; r s = 0.681, p < 0.01; r s = 0.540, p < 0.01; r s = 0.725, p < 0.01; r s = 0.663, p < 0.01) and linear relationship (χ 2 = 56.763, p < 0.01; χ 2 = 55.350, p < 0.01; χ 2 = 34.776, p < 0.01; χ 2 = 62.523, p < 0.01; χ 2 = 52.521, p < 0.01) in liver tissue. The high expression of NLRP3, GSDMD, caspase1, IL-1ß, and IL-18 may be involved in the process of liver tissue inflammation and damage, which is positively correlated with liver tissue inflammation in patients with CHB.

Dihydrotanshinone Inhibits Hepatocellular Carcinoma by Suppressing the JAK2/STAT3 Pathway.

Liver cancer is the sixth most commonly diagnosed cancer and the fourth leading cause of cancer death. Most (75-85%) primary liver cancers occurring worldwide are hepatocellular carcinoma (HCC). The development of resistance and other drug related side effects are the prime reasons for the failure of treatment. Therefore, developing high-efficacy and low-toxicity natural anticancer agents is greatly needed in the treatment of HCC. Dihydrotanshinone (DHTS) is widely used for promoting blood circulation and antitumor. The aim of the present study was to investigate the effect and mechanism of DHTS-induced apoptosis of HCC, both in vitro and in vivo. We found that DHTS inhibited the growth of several HCC cells (HCCLM3, SMMC7721, Hep3B and HepG2). DHTS induced the apoptosis of SMMC7721 cells. Immunofluorescence results have showed that DHTS decreased STAT3 nuclear translocation. Moreover, Western blot results have demonstrated that DHTS suppressed the activation of JAK2/STAT3 signaling pathway. In addition, xenograft results have showed that DHTS suppressed tumor growth of SMMC7721 cells in vivo by inhibiting the p-STAT3. Thus, we demonstrated that DHTS could inhibit HCC by suppressing the JAK2/STAT3 pathway. DHTS has potential to be a chemotherapeutic agent in HCC and merits further clinical investigation.

Histone Deacetylase 6 Regulates the Activation of M1 Macrophages by the Glycolytic Pathway During Acute Liver Failure.

BACKGROUND: The glycolysis pathway of M1 macrophages is a key factor affecting the inflammatory response. The aim of this article is to investigate the role of histone deacetylase 6 (HDAC6) in the M1 macrophage glycolysis pathway during acute liver failure (ALF). METHODOLOGY: Targeted metabolomics for quantitative analysis of energy metabolites technology was used to detect the characteristics of energy metabolism for 8 ALF patients and 8 normal volunteers. The ALF mice model was intervened with HDAC6 inhibitor ACY-1215. iTRAQ/TMT quantitative proteomics was used to detect protein expression in livers in different mice groups. The liver function, energy metabolites, M1 macrophages, cytokines, and pathological structure, DDX3X, NLRP3 and DNMT1 in liver tissue were detected. The changes of the above molecules were verified in cell groups. RESULTS: ALF patients and mice have significant energy metabolism disorders, accompanied by activation of M1 macrophages. After the intervention of ACY-1215, the activated M1 macrophages and cytokines levels in the mouse liver were reduced. The levels of IDH1, MDH1, and ATP were significantly increased. The expression of DDX3X increased, while the expression of NLRP3 and DNMT1 decreased. ACY-1215 could reduce the model cell apoptosis level and inflammatory response, and improve energy metabolism. It could also promote the expression of DDX3X, and inhibit the expression of NLRP3 and DNMT1. CONCLUSION: ACY-1215 could inhibit the activation of M1 macrophages by improving the glycolytic pathway through regulating DNMT1 and DDX3X/NLRP3 signals to alleviate ALF.

Histone deacetylase 2 regulates ULK1 mediated pyroptosis during acute liver failure by the K68 acetylation site.

Pyroptosis is a new necrosis pattern of hepatocyte during liver inflammation in acute liver failure (ALF). Histone deacetylase 2 (HDAC2) is associated with several pathological conditions in the liver system. The aim of this study is to investigate whether knockdown or pharmacological inhibition of HDAC2 could reduce the level of pyroptosis in ALF through ULK1-NLRP3-pyroptosis pathway. The role of HDAC2 on ULK1-NLRP3-pyroptosis pathway during ALF was detected in clinical samples. The mechanism was investigated in transfected cells or in ALF mouse model. The RNA-sequencing results revealed that ULK1 was a negative target regulatory molecule by HDAC2. During the process of pyroptosis, the HDAC2 exerted the antagonistic effect with ULK1 by the K68 acetylation site in L02 cells. Then the role of HDAC2 on ULK1-NLRP3-pyroptosis pathway in ALF mouse model was also detected. Moreover, the related molecules to ULK1-NLRP3-pyroptosis pathway were verified different expression in normal health donors and clinical ALF patients. HDAC2 in hepatocytes plays a pivotal role in an ULK1-NLRP3 pathway driven auto-amplification of pyroptosis in ALF. One of the important mechanisms is that inhibition HDAC2 to reduce pyroptosis may be by modulating the K68 lysine site of ULK1.

Betaine inhibits Toll-like receptor 4 responses and restores intestinal microbiota in acute liver failure mice.

Previous research has revealed that the gut microbiome has a marked impact on acute liver failure (ALF). Here, we evaluated the impact of betaine on the gut microbiota composition in an ALF animal model. The potential protective effect of betaine by regulating Toll-like receptor 4 (TLR4) responses was explored as well. Both mouse and cell experiments included normal, model, and betaine groups. The rat small intestinal cell line IEC-18 was used for in vitro experiments. Betaine ameliorated the small intestine tissue and IEC-18 cell damage in the model group by reducing the high expression of TLR4 and MyD88. Furthermore, the intestinal permeability in the model group was improved by enhancing the expression of the (ZO)-1 and occludin tight junction proteins. There were 509 operational taxonomic units (OTUs) that were identified in mouse fecal samples, including 156 core microbiome taxa. Betaine significantly improved the microbial communities, depleted the gut microbiota constituents Coriobacteriaceae, Lachnospiraceae, Enterorhabdus and Coriobacteriales and markedly enriched the taxa Bacteroidaceae, Bacteroides, Parabacteroides and Prevotella in the model group. Betaine effectively improved intestinal injury in ALF by inhibiting the TLR4/MyD88 signaling pathway, improving the intestinal mucosal barrier and maintaining the gut microbiota composition.

SENP7 knockdown inhibited pyroptosis and NF-κB/NLRP3 inflammasome pathway activation in Raw 264.7 cells.

Pyroptosis is a kind of necrotic and inflammatory programmed cell death induced by inflammatory caspases. SENP7 is a SUMO-specific protease, which mainly acts on deconjugation of SUMOs from substrate proteins. We evaluated the effect of SENP7 knockdown on pyroptosis, NF-κB signaling pathway, and NLRP3 inflammasome in Raw 264.7 cells. The results showed that the GSDMD protein mainly expressed in the cytoplasm nearby nuclei of Raw 264.7 cells. It migrated to cytomembrane with the numbers of Raw 264.7 cell decreased when LPS + ATP were administrated. Which was inhibited by SENP7 knockdown. In addition, not only the pyroptosis of Raw 264.7 cells was inhibited, the activation of NF-κB signaling pathway and NLRP3 inflammasome were also attenuated by SENP7 knockdown. The mechanism may be associated with the over SUMOylation of proteins induced by SENP7 knockdown.

The Beneficial Roles of SIRT1 in Neuroinflammation-Related Diseases.

Sirtuins are the class III of histone deacetylases whose deacetylate of histones is dependent on nicotinamide adenine dinucleotide (NAD+). Among seven sirtuins, SIRT1 plays a critical role in modulating a wide range of physiological processes, including apoptosis, DNA repair, inflammatory response, metabolism, cancer, and stress. Neuroinflammation is associated with many neurological diseases, including ischemic stroke, bacterial infections, traumatic brain injury, Alzheimer's disease (AD), and Parkinson's disease (PD). Recently, numerous studies indicate the protective effects of SIRT1 in neuroinflammation-related diseases. Here, we review the latest progress regarding the anti-inflammatory and neuroprotective effects of SIRT1. First, we introduce the structure, catalytic mechanism, and functions of SIRT1. Next, we discuss the molecular mechanisms of SIRT1 in the regulation of neuroinflammation. Finally, we analyze the mechanisms and effects of SIRT1 in several common neuroinflammation-associated diseases, such as cerebral ischemia, traumatic brain injury, spinal cord injury, AD, and PD. Taken together, this information implies that SIRT1 may serve as a promising therapeutic target for the treatment of neuroinflammation-associated disorders.

Sinomenine Attenuates Acetaminophen-Induced Acute Liver Injury by Decreasing Oxidative Stress and Inflammatory Response via Regulating TGF-ß/Smad Pathway in vitro and in vivo.

INTRODUCTION: Liver disease is common and often life-threatening. Sinomenine (SIN) is an active ingredient extracted from  Sinomenium acutum. This study investigated the protective effect and mechanism of sinomenine (SIN) on acetaminophen (APAP)-induced liver injury from in vitro and in vivo. METHODS: In vivo experiments, mice were randomly divided into six groups (n=10): control group, model group, SIN (25 mg/kg) group, SIN (50 mg/kg) group, SIN (100 mg/kg) group and SIN (100 mg/kg) + SRI-011381 group. Alanine transaminases (ALT), aspartate transaminases (AST) and alkaline phosphatase (ALP) were detected. The pathological lesion was measured by HE staining. Apoptosis was measured by TUNEL staining. In vitro experiments, BRL-3A cells were treated with APAP (7.5 mM) and then subjected to various doses of SIN (10, 50 and 100 µg/mL) at 37°C for 24 h. Inflammatory factors and oxidative stress index were measured by ELISA. The expression of proteins was detected by Western blot. RESULTS: The results showed that compared with the control group, the levels of ALT, AST and ALP in the serum of APAP-induced mice were significantly increased, followed by liver histological damage and hepatocyte apoptosis. Besides, APAP reduced the activity of SOD and GSH-Px, while increasing the content of MDA and LDH. Notably, APAP also promoted the expression of NLRP3, ASC, caspase-1 and IL-1ß. Interestingly, SIN treatment dose-dependently reduced APAP-induced liver injury and oxidative stress, inhibited the activation of NLRP3 inflammasomes, and reduced the levels of inflammatory cytokines. In vitro studies have shown that SIN treatment significantly reduced the viability of BRL-3A cells and oxidative stress and inflammation. In addition, the Western blotting analysis showed that SIN inhibited the activation of TGF-ß/Smad pathway in a dose-dependent manner in vitro and in vivo. These effects were significantly reversed by TGF-ß/Smad activator SRI-011381 or TGF-ß overexpression. DISCUSSION: The study indicates that SIN attenuates APAP-induced acute liver injury by decreasing oxidative stress and inflammatory response via TGF-ß/Smad pathway in vitro and in vivo.

Histone deacetylase 6 inhibitor ACY1215 ameliorates mitochondrial dynamic and function injury in hepatocytes by activating AMPK signaling pathway in acute liver failure mice.

Acute liver failure (ALF) is often accompanied by dynamic and functional disorders of mitochondria in hepatocytes. The histone deacetylase 6 inhibitor Rocilinostat (ACY1215) has a hepatoprotective effect. However, its protective effect on mitochondria of hepatocytes and its related mechanisms in ALF remain unknown. The purpose of the present study was to elucidate the protective effect of ACY1215 on mitochondrial of hepatocytes in ALF by regulating AMPK signaling pathway. LPS and D-Gal were used to induce ALF model in C57BL/6 mice. D-Gal and TNF-α were applied in L02 cells as model group. ACY1215 was administered to the mice or culture cells before the model' s establishment as ACY1215 group. The normal group in mice and L02 cells was not given any drug intervention. ACY1215 improves liver histological and functional changes in ALF model mice. Compared with normal group, the expression of p-AMPK and p-ACC proteins was decreased in model group. ACY1215 activated the AMPK signaling pathway with an increase of p-AMPK and p-ACC proteins level in model group. ACY1215 treatment decreased levels of mitochondrial fission proteins DRP1 and FIS1, and enhanced levels of mitochondrial fusion proteins MFN1, MFN2 and OPA1 in models. MtDNA copies in model group was decreased compared with normal group, but ACY1215 elevated the mtDNA copies in models. Mitochondrial respiratory electron transfer chain Complex I-III and citrate synthase (CS) activities in model group were decreased compared with normal group, but ACY1215 treatment enhanced these activities in model group. ACY1215 protects against dynamic disorders and dysfunction of mitochondria in hepatocytes in ALF by activating AMPK signaling pathway.

Extracellular Histone H3 Induces Pyroptosis During Sepsis and May Act Through NOD2 and VSIG4/NLRP3 Pathways.

Background: Histones could be released from the nucleus when stimulated. Increasing evidence has shown that extracellular histones are associated with a variety of inflammation and diseases. Nucleotide binding oligomerzation domain 2 (NOD2) belongs to the NOD like receptor (NLR) family and is reported to promote apoptosis and aggravate inflammatory response. And V-set and immunoglobulin domain containing 4 (VSIG4), a B7 family-related protein, has been confirmed to mediate transcriptional inhibition of nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3). However, little is known about the impact of extracellular histones on NOD2 or VSIG4 signal transduction. In this study, we aim to explore the effect and mechanism of extracellular histone H3 on pyroptosis. Aim: The purpose of this work was to investigate the mechanism of extracellular histone H3 on pyroptosis in sepsis. Methods: Lipopolysaccharide (LPS) and histone H3 were used to induce sepsis mice model and damage in ANA-1 macrophages. H3 antibody was applied to antagonize the effect of histone H3. NOD2 inhibitor NOD-IN-1 and VSIG4-siRNA were used to investigate the mechanism of histone H3 on pyroptosis. Enzyme linked immune sorbent assay (ELISA) was applied to detect the level of extracellular histone H3. Real-time PCR and Western blotting were employed to detect the key mRNA and protein levels. The pathology of tissues was detected. Results: The level of extracellular histone H3 was increased after LPS stimulation. The mRNA and protein levels of NLRP3, caspase-1, gasdermin D (GSDMD), interleukin (IL)-1ß, IL-18 were increased in LPS group, but suppressed by H3 antibody. And the expression of NOD2, receptor-interacting protein 2 (RIP2) was elevated compared with control group. The expression of VSIG4 was inhibited by LPS and suppression of H3 promoted the protein level of VSIG4. H3 antibody alleviated pathological damages in tissues. Furthermore, the mRNA and protein levels of NOD2 in H3 group was higher compared with control group. The mRNA and protein levels of VSIG4 in H3 group was decreased compared with control group, but up-regulated by NOD-IN-1. Besides, the mRNA and protein levels of VSIG4 in NOD-IN-1 + VSIG4-siRNA group was elevated compared with VSIG4-siRNA group. Conclusions: Extracellular histone H3 induced by LPS could cause pyroptosis during sepsis via NOD2 and VSIG4/NLRP3 pathway.

TNF-α/HMGB1 inflammation signalling pathway regulates pyroptosis during liver failure and acute kidney injury.

OBJECTIVE: Acute kidney injury (AKI) is a common complication of acute liver failure (ALF). Pyroptosis is a necrosis type related to inflammation. This study aimed to investigate the role of TNF-α/HMGB1 pathway in pyroptosis during ALF and AKI. METHODS: An ALF and AKI mouse model was generated using LPS/D-Gal, and a TNF-α inhibitor, CC-5013, was used to treat the mice. THP-1 cells were induced to differentiate into M1 macrophages, then challenged with either CC-5013 or an HMGB1 inhibitor, glycyrrhizin. pLVX-mCMVZsGreen-PGK-Puros plasmids containing TNF-α wild-type (WT), mutation A94T of TNF-α and mutation P84L of TNF-α were transfected into M1 macrophages. RESULTS: Treatment with CC-5013 decreased the activation of TNF-α/HMGB1 pathway and pyroptosis in the treated mice and cells compared with the control mice and cells. CC-5013 also ameliorated liver and kidney pathological changes and improved liver and renal functions in treated mice, and the number of M1 macrophages in the liver and kidney tissues also decreased. The activation of TNF-α/HMGB1 pathway and pyroptosis increased in the M1 macrophage group compared with the normal group. Similarly, the activation of TNF-α/HMGB1 pathway and pyroptosis in the LPS + WT group also increased. By contrast, the activation of the TNF-α/HMGB1 pathway and pyroptosis decreased in the LPS + A94T and LPS + P84L groups. Moreover, glycyrrhizin inhibited pyroptosis. CONCLUSION: The TNF-α/HMGB1 inflammation signalling pathway plays an important role in pyroptosis during ALF and AKI.

AGK2 Alleviates Lipopolysaccharide Induced Neuroinflammation through Regulation of Mitogen-Activated Protein Kinase Phosphatase-1.

Neuroinflammation is associated with the progression of multiple neurological diseases. Many studies show that SIRT2 involves in multiple inflammatory processes. While, the mechanisms remain unclear. The purpose of this study was to explore the effect of SIRT2 inhibitor AGK2 on inflammatory responses and MAPK signaling pathways in LPS activated microglia in vitro and in vivo. The effect of AGK2 on cell viability of BV2 microglial cells was detected by CCK-8 assay. The expression of inflammatory cytokine iNOS was analyzed by western blotting and immunofluorescence. The mRNA expressions of iNOS, TNF-α, and IL-1ß were detected by real-time polymerase chain reaction (RT-PCR). The SIRT2, phospho-P38, P38, phospho-JNK, JNK, phospho-ERK, ERK, α-tubulin, and acetyl-α-tubulin were analyzed by western blotting respectively. The interaction between SIRT2 and MKP-1 was measured by Co-immunoprecipitation (Co-IP) assay. Double immunofluorescent staining was performed to detect the expressions of CD11b and iNOS or SIRT2 in brain tissues. We found that AGK2 could suppress LPS-induced inflammatory cytokines (iNOS, TNF-α, and IL-1ß) expression levels in BV2 microglial cells. Moreover, it could effectively reduce the expression of SIRT2 and increase the acetylation of α-tubulin in LPS activated BV2 microglial cells and LPS induced mice neuroinflammation. In addition, our results showed that AGK2 could reduce the increase of phosphorylation p38, JNK, and ERK after LPS challenge. Co-IP results showed that there was no direct interaction between MKP-1 and SIRT2. However, AGK2 by inhibition of SIRT2 could increase the expression of MKP-1. Furthermore, AGK2 could inhibit the activation of BV2 microglia and expression of iNOS and SIRT2 in LPS treated mice brain tissue. Taken together, our results suggested that AGK2 might alleviate lipopolysaccharide induced neuroinflammation through regulation of mitogen-activated protein kinase phosphatase-1. Graphical abstract.

Histone deacetylase 6 inhibitor ACY1215 offers a protective effect through the autophagy pathway in acute liver failure.

AIM: The purpose of the present study was to elucidate the protective effect of histone deacetylase 6 inhibitor ACY1215 on autophagy pathway in acute liver failure (ALF). MAIN METHODS: Lipopolysaccharide (LPS) and d-galactosamine (D-Gal) were used to induce ALF model in C57BL/6 mice. D-Gal and tumor necrosis factor alpha (TNF-α) were applied in L02 cell. Autophagy inhibitor 3-MA and ACY1215 were conducted to induce 3-MA group, ACY1215 group and ACY1215+3-MA group. RESULTS: ACY1215 improved liver histological and functional changes in ALF mice model, whereas the autophagy inhibitor 3-MA aggravated liver tissue pathological and functional damage in ALF mice model group. The apoptotic levels (including apoptotic index/rate and apoptotic proteins) in ALF mice and L02 cell were ameliorated with treatment ACY1215. 3-MA accentuated the apoptotic levels in ACY1215 group. D-Gal/TNF-α could reduce L02 cell mitochondrial membrane potential (ΔΨm) in control group. ACY1215 increased the ΔΨm in ALF model. 3-MA also further reduced the ΔΨm in ACY1215 group. ACY1215 could induce autophagy in ALF mice and cell model group accompanied with an increase in expression of LC3-II and beclin-1 proteins and down-regulation of p62 protein. Moreover, the expression of LC3-II and beclin1 proteins were greatly reduced and the expression of p62 protein was ascended after intervention with 3-MA in ACY1215 group. SIGNIFICANCE: Histone deacetylase 6 inhibitor ACY1215 could protect acute liver failure mice and L02 cell by inhibiting apoptosis pathway through enhancing autophagy way.

Mechanism of glycyrrhizin on ferroptosis during acute liver failure by inhibiting oxidative stress.

The present study aimed to investigate the anti­ferroptosis effects of the HMGB1 inhibitor glycyrrhizin (GLY). The present study used a cell and animal model of acute liver failure (ALF), induced using tumor necrosis factor­α, lipopolysaccharide and D­galactosamine, to investigate the effects of GLY. The expression of glutathione peroxidase 4 (GPX4) and high mobility group protein B1 (HMGB1), heme oxygenase­1 (HO­1) and nuclear factor erythroid 2­related factor 2 (Nrf2) were detected were detected by western blotting in L02 hepatocytes and mouse liver. The expression of GPX4 and HMGB1 in L02 hepatocytes and mouse liver was detected by immunofluorescence. The pathological changes to liver tissues were determined by hematoxylin and eosin staining. The levels of lactate dehydrogenase (LDH), Fe2+, reactive oxygen species (ROS) and glutathione (GSH) were tested using kits. Compared with the normal group, the degree of liver damage and liver function in the model animal group was severe. The protein levels of HMGB1 in L02 cells and liver tissues were significantly increased. The expression of NRF2, HO­1 and GPX4 was significantly decreased. The levels of LDH, Fe2+, malondialdehyde (MDA) and ROS were increased, whereas the level of GSH was decreased. Treatment with GLY reduced the degree of liver damage, the expression of HMGB1 was decreased, and the levels of Nrf2, HO­1 and GPX4 were increased. The levels of LDH, Fe2+, MDA, ROS were decreased, while the level of GSH was increased by GLY treatment. The results of the present study indicated that HMGB1 is involved in the process of ferroptosis. The HMGB1 inhibitor GLY significantly reduced the degree of ferroptosis during ALF by inhibiting oxidative stress.