Oral administration of grape-derived nanovesicles for protection against LPS/D-GalN-induced acute liver failure.

Although the exploration of the molecular mechanisms of Acute liver failure (ALF) is supported by a growing number of studies, the lack of effective therapeutic agents and measures indicates an urgent clinical need for the development of new drugs and treatment strategies. Herein, we focused on the treatment of ALF with grape-derived nanovesicles (GDNVs), and assessed its protective effects and molecular mechanisms against liver injury. In the mice model of ALF, prophylactic administration for three consecutive days and treatment with GDNVs after successful induction of ALF showed a significant reduction of ALT and AST activity in mouse serum, as well as a blockade of the release of inflammatory cytokines IL6, IL-1ß and TNF-α. Treatment with GDNVs significantly prevented the massive apoptosis of hepatocytes caused by LPS/D-GalN and down-regulated the activation and expression of the mitochondrial apoptosis-related proteins p53, Caspase 9, Caspase 8, Caspase 3 and Bax. GDNVs downregulated the release of chemokines during the inflammatory eruption in mice and inhibited the infiltration of peripheral monocytes into the liver by inhibiting CCR2/CCR5. Moreover, the pro-inflammatory phenotype of macrophages in the liver was reversed by GDNVs. GDNVs further reduced the activation of NLRP3-related pathways, and treatment with GDNVs activated the expression of autophagy-related proteins Foxo3a, Sirt1 and LC3-II in the damaged mouse liver, inducing autophagy to occur. GDNVs could exert hepatoprotective and inflammatory suppressive functions by increasing nuclear translocation of Nrf2 and upregulating HO-1 expression against exogenous toxin-induced oxidative stress in the liver. In conclusion, these results demonstrate that GDNVs alleviate LPS/D-GalN-induced ALF and have the potential to be used as a novel hepatoprotective agent for clinical treatment.

AGK2 pre-treatment protects against thioacetamide-induced acute liver failure via regulating the MFN2-PERK axis and ferroptosis signaling pathway.

BACKGROUND: Acute liver failure (ALF) is an unpredictable and life-threatening critical illness. The pathological characteristic of ALF is massive necrosis of hepatocytes and lots of inflammatory cells infiltration which may lead to multiple organ failure. METHODS: Animals were divided into 3 groups, normal, thioacetamide (TAA, ALF model) and TAA + AGK2. Cultured L02 cells were divided into 5 groups, normal, TAA, TAA + mitofusin 2 (MFN2)-siRNA, TAA + AGK2, and TAA + AGK2 + MFN2-siRNA groups. The liver histology was evaluated with hematoxylin and eosin staining, inositol-requiring enzyme 1 (IRE1), activating transcription factor 6ß (ATF6ß), protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK) and phosphorylated-PERK (p-PERK). C/EBP homologous protein (CHOP), reactive oxygen species (ROS), MFN2 and glutathione peroxidase 4 (GPX4) were measured with Western blotting, and cell viability and liver chemistry were also measured. Mitochondria-associated endoplasmic reticulum membranes (MAMs) were measured by immunofluorescence. RESULTS: The liver tissue in the ALF group had massive inflammatory cell infiltration and hepatocytes necrosis, which were reduced by AGK2 pre-treatment. In comparison to the normal group, apoptosis rate and levels of IRE1, ATF6ß, p-PERK, CHOP, ROS and Fe2+ in the TAA-induced ALF model group were significantly increased, which were decreased by AGK2 pre-treatment. The levels of MFN2 and GPX4 were decreased in TAA-induced mice compared with the normal group, which were enhanced by AGK2 pre-treatment. Compared with the TAA-induced L02 cell, apoptosis rate and levels of IRE1, ATF6ß, p-PERK, CHOP, ROS and Fe2+ were further increased and levels of MFN2 and GPX4 were decreased in the MFN2-siRNA group. AGK2 pre-treatment decreased the apoptosis rate and levels of IRE1, ATF6ß, p-PERK, CHOP, ROS and Fe2+ and enhanced the protein expression of MFN2 and GPX4 in MFN2-siRNA treated L02 cell. Immunofluorescence observation showed that level of MAMs was promoted in the AGK2 pre-treatment group when compared with the TAA-induced group in both mice and L02 cells. CONCLUSIONS: The data suggested that AGK2 pre-treatment had hepatoprotective role in TAA-induced ALF via upregulating the expression of MFN2 and then inhibiting PERK and ferroptosis pathway in ALF.

Artificial cells delivering itaconic acid induce anti-inflammatory memory-like macrophages to reverse acute liver failure and prevent reinjury.

Hepatic macrophages represent a key cellular component of the liver and are essential for the progression of acute liver failure (ALF). We construct artificial apoptotic cells loaded with itaconic acid (AI-Cells), wherein the compositions of the synthetic plasma membrane and surface topology are rationally engineered. AI-Cells are predominantly localized to the liver and further transport to hepatic macrophages. Intravenous administration of AI-Cells modulates macrophage inflammation to protect the liver from acetaminophen-induced ALF. Mechanistically, AI-Cells act on caspase-1 to suppress NLRP3 inflammasome-mediated cleavage of pro-IL-1ß into its active form in macrophages. Notably, AI-Cells specifically induce anti-inflammatory memory-like hepatic macrophages in ALF mice, which prevent constitutive overproduction of IL-1ß when liver reinjury occurs. In light of AI-Cells' precise delivery and training of memory-like hepatic macrophages, they offer promising therapeutic potential in reversing ALF by finely controlling inflammatory responses and orchestrating liver homeostasis, which potentially affect the treatment of various types of liver failure.

Fluorofenidone protects against acute liver failure in mice by regulating MKK4/JNK pathway.

AIMS: Acute liver failure (ALF) is a life-threatening disease characterized by abrupt and extensive hepatic necrosis and apoptosis, resulting in high mortality. The approved drug, N-acetylcysteine (NAC), is only effective for acetaminophen (APAP)-associated ALF at the early stage. Thus, we investigate whether fluorofenidone (AKF-PD), a novel antifibrosis pyridone agent, protects against ALF in mice and explore its underlying mechanisms. METHODS: ALF mouse models were established using APAP or lipopolysaccharide/D-galactosamine (LPS/D-Gal). Anisomycin and SP600125 were used as JNK activator and inhibitor, respectively, and NAC served as a positive control. Mouse hepatic cell line AML12 and primary mouse hepatocytes were used for in vitro studies. RESULTS: AKF-PD pretreatment alleviated APAP-induced ALF with decreased necrosis, apoptosis, reactive oxygen species (ROS) markers, and mitochondrial permeability transition in liver. Additionally, AKF-PD alleviated mitochondrial ROS stimulated by APAP in AML12 cells. RNA-sequencing in the liver and subsequent gene set enrichment analysis showed that AKF-PD significantly impacted MAPK and IL-17 pathway. In vitro and in vivo studies demonstrated that AKF-PD inhibited APAP-induced phosphorylation of MKK4/JNK, while SP600125 only inhibited JNK phosphorylation. The protective effect of AKF-PD was abolished by anisomycin. Similarly, AKF-PD pretreatment abolished hepatotoxicity caused by LPS/D-Gal, decreased ROS levels, and diminished inflammation. Furthermore, unlike NAC, AKF-PD, inhibited the phosphorylation of MKK4 and JNK upon pretreatment, and improved survival in cases of LPS/D-Gal-induced mortality with delayed dosing. CONCLUSIONS: In summary, AKF-PD can protect against ALF caused by APAP or LPS/D-Gal, in part, via regulating MKK4/JNK pathway. AKF-PD might be a novel candidate drug for ALF.

VX-765 inhibits pyroptosis and reduces inflammation to prevent acute liver failure by upregulating PPARα expression.

INTRODUCTION AND OBJECTIVES: As a fatal clinical syndrome, acute liver failure (ALF) is characterized by overwhelming liver inflammation and hepatic cell death. Finding new therapeutic methods has been a challenge in ALF research. VX-765 is a known pyroptosis inhibitor and has been reported to prevent damage in a variety of diseases by reducing inflammation. However, the role of VX-765 in ALF is still unclear. MATERIALS AND METHODS: ALF model mice were treated with D-galactosamine (D-GalN) and lipopolysaccharide (LPS). LO2 cells were stimulated with LPS. Thirty subjects were enrolled in clinical experiments. The levels of inflammatory cytokines, pyroptosis-associated proteins and peroxisome proliferator-activated receptor α (PPARα) were detected using quantitative reverse transcription-polymerase chain reaction (qRT‒PCR), western blotting and immunohistochemistry. An automatic biochemical analyzer was used to determine the serum aminotransferase enzyme levels. Hematoxylin and eosin (HE) staining was used to observe the pathological features of the liver. RESULTS: With the progression of ALF, the expression levels of interleukin (IL) -1ß, IL-18, caspase-1, and serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were increased. VX-765 could reduce the mortality rate of ALF mice, relieve liver pathological damage, and reduce inflammatory responses to protect against ALF. Further experiments showed that VX-765 could protect against ALF through PPARα, and this protective effect against ALF was reduced in the context of PPARα inhibition. CONCLUSIONS: As ALF progresses, inflammatory responses and pyroptosis deteriorate gradually. VX-765 can inhibit pyroptosis and reduce inflammatory responses to protect against ALF by upregulating PPARα expression, thus providing a possible therapeutic strategy for ALF.

Design and synthesis of hederagenin derivatives modulating STING/NF-κB signaling for the relief of acute liver injury in septic mice.

Systemic inflammatory responses often result in sepsis and inhibition of inflammation is one strategy for sepsis treatment. In this study, we designed and synthesized 32 novel hederagenin (HD) derivatives with modifications at the A-ring, C-28, and C-23 positions and screened their anti-inflammatory activities in vitro, finding multiple compounds with potential anti-inflammatory activity. Of these, compound 1 was the most effective and was used for subsequent investigations into its mechanism of action and in vivo activity. In vivo assessments of anti-inflammatory activity showed that compound 1 reduced inflammation in a mouse model of sepsis with acute liver injury caused by lipopolysaccharide (LPS). Compound 1 also inhibited STING, p-IRF3, p-TBK1, p-p65, and p-IκB proteins in cGAS-STING-associated signaling. These findings indicated that compound 1 reduced inflammation through inhibition of STING expression and hence reducing activation of STING and nuclear factor-κB (NF-κB) signaling. Our work demonstrated that compound 1 is a promising lead compound for designing and developing anti-sepsis drugs.

Orientin reverses acetaminophen-induced acute liver failure by inhibiting oxidative stress and mitochondrial dysfunction.

Oxidative stress, as an important pathogenic factor, plays a critical role in acetaminophen (APAP) overdose-induced acute liver failure (ALF). Thus, an antioxidative strategy may be a good way to alleviate APAP-induced liver damage. Previous research has reported that Orientin (Ori) possesses antioxidant, anti-inflammatory and anticancer effects. This study aimed to explore whether Ori can protect against APAP-induced oxidative stress and to elucidate its underlying mechanism. Our results indicated that Ori alleviated APAP-induced hepatic pathological changes by reducing mouse mortality, inhibiting the expression of cytochrome P450 2E1 (CYP2E1), maintaining a normal liver structure, and reducing the levels of serum alanine transaminase (ALT) and serum aspartate aminotransferase (AST). Moreover, Ori protected against APAP-induced oxidative damage by decreasing the formation of malondialdehyde (MDA) and myeloperoxidase (MPO) and increasing the levels of superoxide dismutase (SOD) and the GSH-to-GSSG ratio. Moreover, Ori regulated APAP-induced hepatocyte apoptosis and mitochondrial dysfunction by inhibiting cytochrome c mitochondrial translocation and c-jun N-terminal kinase phosphorylation, promoting Bcl-2 expression and reducing Bax and caspase-3 cleavage. Furthermore, Ori not only obviously promoted Nrf2 nuclear translocation but also activated the antioxidant-related proteins HO-1, GCLC, GCLM and NQO1. Therefore, Ori prevented APAP-induced hepatocyte oxidative damage and mitochondrial dysfunction via Nrf2-mediated and JNK/cytochrome c/caspase-3 signaling pathways.

Amygdalin protects against acetaminophen-induced acute liver failure by reducing inflammatory response and inhibiting hepatocyte death.

Amygdalin is a natural compound from Bitter Apricot Seed which is reported to have anti-inflammatory activity. Acetaminophen (APAP) resulted in drug-induced liver injury is the main cause of acute liver failure (ALI) worldwide and only N-acetylcysteine is the accepted detoxification drug. However, there is no effective medicine to perfect the hepatocyte death and secondary inflammation injury. In this study, we aim to investigate the protective effect of Amygdalin in the APAP-induced acute liver failure mice model. We establish the ALI model via intraperitoneal APAP injection and mice were treated with Amygdalin with intraperitoneal injection. We detected liver enzyme and histological change to evaluate the liver injury. We measured oxidative damage markers and inflammatory cell infiltration of liver tissues. At last, we investigated the mechanism of Amygdalin on protecting hepatocytes. Results showed that Amygdalin reduced ALT/AST level and decreased necrotic area of liver tissue. In addition, Amygdalin reduced the count of MPO+(neutrophils) and F4/80+(macrophages) of the liver and inhibited IL-6, TNF-a, and IL-1b expression. Amygdalin reduced liver SOD and MDA levels and increased Nrf2/NQO1/HO1 protein expression. Moreover, Amygdalin reduced TUNEL+ and P-MLKL + staining cells in liver tissue. Mechanically, Amygdalin promoted phosphorylation of AKT and suppressed JNK/RIP3/MLKL signaling.

Naringenin affords protection against lipopolysaccharide/D-galactosamine-induced acute liver failure: Role of autophagy.

Acute liver failure (ALF) is considered a fatal clinical disorder and novel therapeutic interventions are mandatory. Naringenin is a flavonoid with anti-inflammatory, antioxidant and antiapoptotic effects that have displayed beneficial effects in different animal models of ALF. The current study aimed at investigating the hepatoprotective effect and the possible underlying molecular mechanisms of naringenin in lipopolysaccharide (LPS)/D-galactosamine (D-Gal) mouse model of ALF. Interestingly, naringenin pretreatment substantially alleviated LPS/D-Gal-induced liver injury, enhanced survival, improved liver function and ameliorated histopathological liver changes. Importantly, naringenin potently activated autophagy as evidenced by the increased Beclin-1 expression and LC3 II/LC3 I ratio. Furthermore, results demonstrated that naringenin alleviated oxidative stress by inducing nuclear factor-erythroid 2-related factor 2 (Nrf2) and increasing hepatic SOD activity and GSH level as well as ameliorated endoplasmic reticulum (ER) stress. Likewise, naringenin mitigated LPS/D-Gal-triggered inflammation by suppressing NF-κB and NLRP3 pathways. Accordingly, apoptotic cell death provoked by LPS/D-Gal challenge was markedly attenuated as depicted by the decrease in caspase-3 and p53 in naringenin-treated mice. To investigate the contribution of autophagy to naringenin-conferred hepatoprotection, autophagy was inhibited using 3-methyladenine (3 MA). Strikingly, 3 MA co-treatment abolished the hepatoprotective effect of naringenin, a finding that strongly suggests that naringenin-afforded protection is, at least in part, attributed to autophagy. Taken together, the present study revealed that naringenin exerted a prominent hepatoprotective effect by promoting autophagy with consequent attenuation of inflammatory responses, oxidative stress, ER stress and apoptosis. Our results provide evidence that naringenin use holds a promise as a potential therapeutic agent for ALF management.

Inhibition of p53 Sulfoconjugation Prevents Oxidative Hepatotoxicity and Acute Liver Failure.

BACKGROUND & AIMS: Sulfoconjugation of small molecules or protein peptides is a key mechanism to ensure biochemical and functional homeostasis in mammals. The PAPS synthase 2 (PAPSS2) is the primary enzyme to synthesize the universal sulfonate donor 3'-phosphoadenosine 5'-phosphosulfate (PAPS). Acetaminophen (APAP) overdose is the leading cause of acute liver failure (ALF), in which oxidative stress is a key pathogenic event, whereas sulfation of APAP contributes to its detoxification. The goal of this study was to determine whether and how PAPSS2 plays a role in APAP-induced ALF. METHODS: Gene expression was analyzed in APAP-induced ALF in patients and mice. Liver-specific Papss2-knockout mice using Alb-Cre (Papss2ΔHC) or AAV8-TBG-Cre (Papss2iΔHC) were created and subjected to APAP-induced ALF. Primary human and mouse hepatocytes were used for in vitro mechanistic analysis. RESULTS: The hepatic expression of PAPSS2 was decreased in APAP-induced ALF in patients and mice. Surprisingly, Papss2ΔHC mice were protected from APAP-induced hepatotoxicity despite having a decreased APAP sulfation, which was accompanied by increased hepatic antioxidative capacity through the activation of the p53-p2-Nrf2 axis. Treatment with a sulfation inhibitor also ameliorated APAP-induced hepatotoxicity. Gene knockdown experiments showed that the hepatoprotective effect of Papss2ΔHC was Nrf2, p53, and p21 dependent. Mechanistically, we identified p53 as a novel substrate of sulfation. Papss2 ablation led to p53 protein accumulation by preventing p53 sulfation, which disrupts p53-MDM2 interaction and p53 ubiquitination and increases p53 protein stability. CONCLUSIONS: We have uncovered a previously unrecognized and p53-mediated role of PAPSS2 in controlling oxidative response. Inhibition of p53 sulfation may be explored for the clinical management of APAP overdose.

Recombinant Human HPS Protects Mice and Nonhuman Primates from Acute Liver Injury.

Acute liver injury shares a common feature of hepatocytes death, immune system disorders, and cellular stress. Hepassocin (HPS) is a hepatokine that has ability to promote hepatocytes proliferation and to protect rats from D-galactose (D-Gal)- or carbon tetrachloride (CCl4)-induced liver injury by stimulating hepatocytes proliferation and preventing the high mortality rate, hepatocyte death, and hepatic inflammation. In this paper, we generated a pharmaceutical-grade recombinant human HPS using mammalian cells expression system and evaluated the effects of HPS administration on the pathogenesis of acute liver injury in monkey and mice. In the model mice of D-galactosamine (D-GalN) plus lipopolysaccharide (LPS)-induced liver injury, HPS treatment significantly reduced hepatocyte death and inflammation response, and consequently attenuated the development of acute liver failure. In the model monkey of D-GalN-induced liver injury, HPS administration promoted hepatocytes proliferation, prevented hepatocyte apoptosis and oxidation stress, and resulted in amelioration of liver injury. Furthermore, the primary pharmacokinetic study showed natural HPS possesses favorable pharmacokinetics; the acute toxicity study indicated no significant changes in behavioral, clinical, or histopathological parameters of HPS-treated mice, implying the clinical potential of HPS. Our results suggest that exogenous HPS has protective effects on acute liver injury in both mice and monkeys. HPS or HPS analogues and mimetics may provide novel drugs for the treatment of acute liver injury.

Isoliquiritigenin alleviates LPS/ D-GalN-induced acute liver failure by activating the PGC-1α/ Nrf2 pathway to reduce oxidative stress and inflammatory response.

Acute liver failure (ALF) is a dramatic liver disease characterized by large areas of inflammation. However, there are no available effective targeted drugs for ALF treatment. In the study, serum biochemical index and H&E were used to explore the amelioration of the liver histopathological changes. The oxidative stress kits, quantitative real-time PCR, western blot, immunohistochemistry, immunofluorescence staining, reactive oxygen species (ROS), and siRNA were used to elucidate the mechanisms underlying isoliquiritigenin (ISL) protection. The results showed that ISL significantly improved the liver pathological changes. Furthermore, ISL reduced oxidative stress by altering the expression of PGC-1α, Nrf2, HO-1, NQO1, Keap1, GCLC, and GCLM in damaged hepatocytes. Moreover, the levels of inflammation-related genes including NLRP3 inflammasome, IL-1ß, IL-6, TNF-α, iNOS, and Mip-2 were repressed by ISL. In addition, ISL alleviated LPS/D-GalN-induced hepatocytes apoptosis by increasing the Bcl-2/Bax ratio and suppressing the expression of cleaved caspase-3. Further in vivo and in vitro evidence proved the involvement of the PGC-1α/Nrf2 signaling pathway in ISL protection. In conclusion, ISL improves the ability of anti-oxidative stress, alleviates inflammatory reaction, apoptosis, and inhibits NLRP3 inflammasome to protect lipopolysaccharide/D-galactosamine (LPS/D-GalN)-induced ALF through activating the PGC-1α/Nrf2 pathway, which provides the possibility for the treatment of ALF.

Molecular mechanisms and therapeutic implications of dihydromyricetin in liver disease.

Recent studies demonstrated that dihydromyricetin (DHM) has prominent therapeutic effects on liver injury and liver cancer. By summarizing the current preclinical in vitro and in vivo studies, the present review examines the preventive and therapeutic effects of DHM on liver disorders as well as its potential mechanisms. Briefly, in both chemical- and alcohol-induced liver injury models, DHM ameliorates hepatocyte necrosis and steatosis while promoting liver regeneration. In addition, DHM can alleviate nonalcoholic fatty liver disease (NAFLD) via regulating lipid/glucose metabolism, probably due to its anti-inflammatory or sirtuins-dependent mechanisms. Furthermore, DHM treatment inhibits cell proliferation, induces apoptosis and autophagy and regulates redox balance in liver cancer cells, thus exhibiting remarkable anti-cancer effects. The pharmacological mechanisms of DHM may be associated with its anti-inflammatory, anti-oxidative and apoptosis-regulatory benefits. With the accumulating interests in utilizing natural products to target common diseases, our work aims to improve the understanding of DHM acting as a novel drug candidate for liver diseases and to accelerate its translation from bench to bedside.

DNA-Aptamer Raised against Receptor for Advanced Glycation End Products Improves Survival Rate in Septic Mice.

Despite remarkable scientific advances in the understanding of molecular mechanisms for sepsis, therapeutic options are far from satisfactory. High mobility group box 1 (HMGB1), one of the ligands of receptor for advanced glycation end products (RAGE), is a late mediator of lethality in septic mice. We have recently found that the DNA-aptamer raised against RAGE (RAGE-aptamer) significantly blocks experimental diabetic nephropathy and melanoma growth and metastasis. We examined the effects of RAGE-aptamer on sepsis score, survival rate, and inflammatory and oxidative stress responses in serum, peripheral monocytes, kidneys and livers of lipopolysaccharide- (LPS-) injected mice, and on LPS-exposed THP-1 cells. RAGE-aptamer inhibited the binding of HMGB1 to RAGE in vitro. RAGE-aptamer significantly (P = 0.002) improved sepsis score at 8 hours after LPS injection and survival rate at 24 hours (P < 0.01, 70%) in septic mice compared with LPS+vehicle- or LPS+control-aptamer-treated mice. RAGE-aptamer treatment significantly decreased expression of p-NF-κB p65, an active form of redox-sensitive transcriptional factor, NF-κB and gene or protein expression of TNF-α, IL-1ß, IL-6, and HMGB1 in serum, peripheral monocytes, and kidneys of septic mice in association with the reduction of oxidative stress and improvement of metabolic acidosis, renal and liver damage. LPS-induced oxidative stress, inflammatory reactions, and growth suppression in THP-1 cells were significantly blocked by RAGE-aptamer. Our present study suggests that RAGE-aptamer could attenuate multiple organ damage in LPS-injected septic mice partly by inhibiting the inflammatory reactions via suppression of HMGB1-RAGE interaction.

[Protective effect of vitamin D in mice with acute liver failure].

Objective: To explore the protective effect of vitamin D in acute liver failure through a mouse model. Methods: Acute liver failure was induced by combining D-galactosamine (D-GalN) lipopolysaccharide (LPS) to observe the effect of long-term vitamin D deficiency on liver injury and inflammatory signals in a mouse model. Acute liver failure was induced by thioacetamide (TAA) to observe the effect of vitamin D deficiency on the survival rate, and further high-dose of vitamin D supplementation protective effect was determined in a mouse model. Liver function was evaluated by measuring serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and liver inflammation by hematoxylin-eosin staining. The expressions of tumor necrosis factor (TNF-α), interleukin (IL) -1ß, NOD-like receptor family, pyrin domain containing 3 (NLRP-3), chemokines (CCL2, CXCL1 and CXCL2), etc. in liver tissues were detected by RT-qPCR. The quantitation of macrophages in liver tissue was detected by immunohistochemistry. The comparison between groups were performed by t-test. The survival curve was analyzed by log-rank (Mantel-Cox) test. Results: Long-term vitamin D deficiency had increased acute liver failure sensitivity in mice, which was manifested by increased blood cell extravasation, massive necrosis of parenchymal cells, up-regulation of TNF-α, IL-1ß, and NLRP-3 mRNA expression (P < 0.05), and increased macrophages quantitation (P < 0.05) in liver tissues. At the same time, vitamin D deficiency had increased the mice mortality rate because of liver injury (P < 0.01). On the contrary, pre-administration of high dose of vitamin D (100 IU/g) had significantly reduced liver injury, inhibited ALT and AST rise (P < 0.01), alleviated liver necrosis, and down-regulated the mRNA expression of inflammatory factors in liver tissues (P < 0.05). Conclusion: Mouse model shows that long-term vitamin D deficiency can aggravate drug-induced acute liver failure and reduce survival rates. Furthermore, high-dose of vitamin D has a certain hepatoprotective effect, which can significantly improve liver necrosis condition and inhibit inflammation. Therefore, adequate vitamin D can retain liver physiological balance to resist liver injury.

Niujiaodihuang Detoxify Decoction inhibits ferroptosis by enhancing glutathione synthesis in acute liver failure models.

ETHNOPHARMACOLOGICAL RELEVANCE: Niujiaodihuang Detoxify Decoction (NDD) is an integrated traditional Chinese medicine prescription that has been used as a therapeutic agent for the treatment of acute liver failure (ALF). However, the mechanisms underlying its action remain unclear. AIM OF THE STUDY: To determine the protective effect of NDD on D-galactosamine/lipopolysaccharide (D-GalN/LPS)-induced ALF and explore the underlying mechanisms. MATERIALS AND METHODS: We characterized the NDD fingerprint by HPLC and established D-GalN/LPS-induced ALF models in Sprague-Dawley rats and LO2 cells. Next, we measured the protective and antiferroptotic effects of NDD in vivo and in vitro. To further investigate the molecular mechanisms underlying the effects of NDD, we performed metabolomic analysis of the liver tissue using LC-MS/MS. RESULTS: Results of serum biochemical analysis, liver histopathology, and cell viability showed that NDD effectively relieved the liver injury. It reduced the accumulation of labile iron and alleviated lipid peroxidation by enhancing GPX4 activity. The mitochondrial morphology indicated that NDD exerted its hepatoprotective effect through an antiferroptotic activity. Metabolomic analysis showed that NDD treatment increased the levels of cysteine, decreased those of glutamate, and ameliorated the D-GalN/LPS-induced reduction in the levels of glutathione (GSH). The results for intracellular levels of reduced (GSH) and oxidized (GSSG) glutathione were consistent with those of metabolomic analysis. CONCLUSION: Our findings indicate that NDD exerts hepatoprotective activity by evoking the reprogramming of GSH metabolism, and thereby, inhibiting ferroptosis.

Gensenoside Rg1 protects against lipopolysaccharide- and d-galactose-induced acute liver failure via suppressing HMGB1-mediated TLR4-NF-κB pathway.

AIM: Acute liver failure (ALF) is a life-threatening acute liver injury (ALI) with high mortality. Gensenoside Rg1 (G-Rg1) effects on Lipopolysaccharide- (LPS-) and d-galactose-(D-gal-) induced ALI, but its effects on ALF remained unclear. This paper aimed to validate its possible efficacy on ALF prevention. METHODS: For in vivo studies, histological examination was performed using hematoxylin-eosin (H&E) staining, and alanine aminotransferase (ALT), aspartate aminotransminase (AST), malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione (GSH) contents were measured. Levels of inflammatory cytokines tumor necrosis factor-α (TNF-α) and Interleukin-6 (IL-6) were quantified via enzyme-linked immunosorbent assay (ELISA). Human bronchial epithelial cell line BEAS-2B was used for ALF model in vitro and its viability was measured by MTT assay. Expressions of high mobility group box 1 (HMGB1) and toll-like receptor 4-Nuclear Factor-κB (TLR4-NF-κB) pathway-related proteins were measured by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot as needed. RESULTS: G-Rg1 relieved LPS- and D-gal-induced hepatic injury, and reduced ALT, AST and MDA levels but upregulated SOD and GSH levels, with downregulation on TNF-α and IL-6 levels. Expressions of HMGB1, TLR4 and NF-κB pathway-related proteins were also down-regulated after G-Rg1 treatment both in vivo and in vitro, while BEAS-2B cell viability was increased. However, overexpressed HMGB1 reversed the effects of G-Rg1 treatment in vitro. CONCLUSION: G-Rg1 had a protective effect against LPS- and D-gal-induced ALF both in vitro and in vivo, which might be related to inhibited HMGB1-mediated TLR4-NF-κB Pathway. These discoveries suggested that G-Rg1 could be a potential agent for prevention against ALF.

Complement-5 Inhibition Deters Progression of Fulminant Hepatitis to Acute Liver Failure in Murine Models.

BACKGROUND & AIMS: Acute liver failure (ALF) is a life-threatening condition with limited treatment alternatives. ALF pathogenesis seemingly involves the complement system. However, no complement-targeted intervention has been clinically applied. In this study, we aimed to investigate the potential of Complement-5 (C5)-targeted ALF treatment. METHODS: ALF was induced in C5-knockout (KO, B10D2/oSn) mice and their wild-type (WT) counterparts (B10D2/nSn) through intraperitoneal lipopolysaccharide (LPS) and d-galactosamine (D-GalN) administration. Thereafter, monoclonal anti-C5 antibody (Ab) or control immunoglobulin was administered intravenously. Furthermore, a selective C5a-receptor (C5aR) antagonist was administered to WT mice to compare its efficacy with that of anti-C5-Ab-mediated total C5 inhibition. We clarified the therapeutic effect of delayed anti-C5-Ab administration after LPS/D-GalN challenge. We also assessed the efficacy of anti-C5-Ab in another ALF model, using concanavalin-A. RESULTS: Liver injury was evident 6 hours after LPS/D-GalN administration. C5-KO and anti-C5-Ab treatment significantly improved overall animal survival and significantly reduced serum transaminase and high-mobility group box-1 release with decreased histological tissue damage. This improvement was characterized by significantly reduced CD41+ platelet aggregation, maintained F4/80+ cells, and less infiltration of CD11+/Ly6-G+ cells with lower cytokine/chemokine expression. Furthermore, C5-KO and anti-C5-Ab downregulated tumor necrosis factor-α production by macrophages before inducing marked liver injury. Moreover, single-stranded-DNA cells and caspase activation were reduced, indicating significant attenuation of apoptosis. Anti-C5-Ab treatment protected the liver more effectively than the C5aR antagonist, and its delayed doses were hepatoprotective. In addition, anti-C5-Ab treatment was effective against concanavalin-A-induced ALF. CONCLUSIONS: C5 inhibition effectively suppresses progression to ALF in mice models of fulminant hepatitis, serving as a new potential treatment strategy for ALF.

Remote Ischemic Preconditioning Attenuates Hepatic Ischemia/Reperfusion Injury after Hemorrhagic Shock by Increasing Autophagy.

Fluid resuscitation after hemorrhagic shock is a model of systemic ischemia/reperfusion injury (SI/RI), and the liver is one of the main target organs. Ischemic preconditioning (IPC) can reduce hepatic ischemia-reperfusion injury (I/RI) via autophagy. However, whether remote ischemic preconditioning (RIPC) can alleviate the liver injury that is secondary to hemorrhagic shock and the role of autophagy in this process remain unclear. Thus, we constructed a hemorrhagic shock model in rats with or without RIPC to monitor mean arterial pressure (MAP) and investigate liver secondary injury levels via serum aminotransferase, ultrasound, HE staining and TUNEL fluorescence staining. We also detected levels of serum inflammatory factors including tumor necrosis factor-alpha (TNF-α) and interleukin 1ß (IL-1ß) by enzyme-linked immunosorbent assay (ELLSA), observed autophagosomes by Transmission electron microscopy (TEM), and analyzed LC3, Beclin-1, p62 protein expression levels by immunohistochemical (IHC) and western blot (WB). We found that RIPC increased blood pressure adaptability, decreased lactate (Lac) and aminotransferase levels, and delayed the decrease in liver density. Levels of inflammatory factors TNF-α, IL-1ß and apoptosis were attenuated, autophagosomes was increased in the RIPC group compared with controls. IHC and WB both revealed increased LC3 and Beclin-1 but decreased p62 protein expression levels in the RIPC group. Together, our data suggest that RIPC-activated autophagy could play a protective role against secondary liver injury following hemorrhagic shock.

LncRNA XIST silencing protects against sepsis-induced acute liver injury via inhibition of BRD4 expression.

Sepsis is recognized as the acute systemic inflammatory response to severe infection. It is main cause of multiple organ system dysfunction and even organ failure. Long non-coding RNA X inactivate-specific transcript (XIST) is implicated in multiple inflammatory diseases. The aim of present work was to investigate the precise mechanism of XIST underlying sepsis-induced acute liver injury. Rats were underwent cecal ligation and puncture (CLP) to establish sepsis-induced the animal models of acute liver injury. Hematoxylin and eosin (H&E) staining was performed to observe pathological alterations. Corresponding commercial assay kits were employed to analyze the levels of inflammatory cytokines and oxidative stress. Western blot and reverse transcriptional quantitative PCR (RT-qPCR) were performed to determine the expression of proteins and target genes. Finally, TUNEL and CCK-8 assays were performed to test apoptosis rate and cell viability, respectively. In our study, XIST and BRD4 were highly expressed in serum of patients with sepsis-induced acute liver injury. XIST knockdown ameliorated sepsis-induced acute liver injury and inhibited inflammation, oxidative stress, and cell apoptosis in sepsis-induced acute liver injury rats. Interestingly, XIST knockdown downregulated the expression of BRD4, and BRD4 overexpression abolished the impacts of XIST knockdown on inflammation, oxidative stress, and apoptosis of that LPS-induced Kupffer cells. We conclude that lncRNA XIST silencing protects against sepsis-induced acute liver injury via inhibition of the BRD4 expression. Therefore, XIST may be a biomarker for sepsis diagnosis and treatment.