OBJECTIVES: To explore the protective effect of vitexin-4 ″-O-glucoside (VOG) against acetaminophen-induced acute liver injury in mice and its underlying mechanism. METHODS: C57BL/6 mice were randomly divided into 4 groups: normal control group, model control group, low-dose group of VOG (30 mg/kg), and high-dose group of VOG (60 mg/kg). Acute liver injury was induced by intraperitoneal injection of acetaminophen (500 mg/kg). VOG was administrated by gavage 2 h before acetaminophen treatment in VOG groups. The protective effect of VOG against acute liver injury was evaluated by detecting alanine transaminase (ALT), aspartate transaminase (AST) levels and hematoxylin and eosin staining. The malondialdehyde (MDA) content, superoxide dismutase (SOD) and catalase (CAT) activity in liver were detected to evaluate the hepatic oxidative stress. The expression levels of tumor necrosis factor (TNF)-α, Il-1β, and Il-6 in liver were detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR). The expression levels of phosphorylated c-jun N-terminal kinase (JNK)/JNK, phosphorylated p38/p38, inositol-requiring enzyme 1 alpha (IRE-1α), X-box binding protein 1s (XBP1s), and glucose-regulated protein 78 (GRP78) in liver were detected by Western blotting. An endoplasmic reticulum stress model was established in AML-12 cells using tunicamycin. Cell viability was assessed using the CCK-8 assay, and the degree of cell damage was detected by lactate dehydrogenase (LDH) assay. The gene expression levels of Ire-1α, Xbp1s, and Grp78 in the cells were detected using qRT-PCR. RESULTS: In the animal experiments, compared with the model control group, VOG significantly improved plasma ALT and AST levels, liver MDA content, as well as SOD and CAT activities. VOG also reduced the expression levels of Tnf-α, Il-1β, and Il-6 in the liver, and improved protein phosphorylation levels of JNK and p38, as well as the protein expression levels of IRE-1α, XBP1s, and GRP78. In cell experiments, VOG pretreatment enhanced cell viability, reduced LDH release and decreased the mRNA expression of Ire-1α, Xbp1s, and Grp78. CONCLUSIONS VOG can suppress inflammation and oxidative stress, and alleviate acetaminophen-induced acute liver injury in mice by suppressing endoplasmic reticulum stress and modulating the MAPK signaling pathway.
Animals ; Endoplasmic Reticulum Chaperone BiP ; Mice ; Acetaminophen/adverse effects* ; Mice, Inbred C57BL ; Chemical and Drug Induced Liver Injury/prevention & control* ; Glucosides/therapeutic use* ; Oxidative Stress/drug effects* ; Male ; Apigenin/therapeutic use* ; Liver/drug effects* ; Tumor Necrosis Factor-alpha/metabolism* ; Endoplasmic Reticulum Stress/drug effects* ; X-Box Binding Protein 1 ; Endoribonucleases/metabolism* ; Interleukin-1beta/metabolism* ; Interleukin-6/metabolism* ; Protein Serine-Threonine Kinases

Acetaminophen (APAP) is the most common antipyretic, analgesic and anti-inflammatory drug, but its overdose often leads to acute liver injury, even acute liver failure, and death in some severe cases. At present, there is still a lack of specific treatments. The c-Jun N-terminal kinase (JNK) signal pathway is one of the potential therapeutic targets identified in recent years in overdose APAP-induced acute liver injury. This article reviews the JNK signaling pathway of APAP in liver metabolism, the activation of JNK signaling pathway and the amplification of oxidative stress, other pathways or cellular processes related to JNK signaling pathway, and the possible challenges of drugs targeting JNK, so as to provide direction and feasibility analysis for further research and clinical application of JNK signaling pathway targets in APAP hepatotoxicity, and to provide reference for searching for other targets.
Animals ; Mice ; Acetaminophen/adverse effects* ; Chemical and Drug Induced Liver Injury ; Chemical and Drug Induced Liver Injury, Chronic/metabolism* ; JNK Mitogen-Activated Protein Kinases/metabolism* ; Liver ; Mice, Inbred C57BL ; Signal Transduction

This study explored the protective effect of atractylenolide Ⅰ(AO-Ⅰ) against acetaminophen(APAP)-induced acute liver injury(ALI) in mice and its underlying mechanism. C57 BL/6 J mice were randomly divided into a control group, an APAP group(500 mg·kg~(-1)), a low-dose combination group(500 mg·kg~(-1) APAP + 60 mg·kg~(-1) AO-Ⅰ), and a high-dose combination group(500 mg·kg~(-1) APAP + 120 mg·kg~(-1) AO-Ⅰ). ALI was induced by intraperitoneal injection of APAP(500 mg·kg~(-1)). AO-Ⅰ by intragastric administration was performed 2 hours before APAP treatment, and the control group received the same dose of solvent by intragastric administration or intraperitoneal injection. The protective effect of AO-Ⅰ against APAP-induced ALI was evaluated by detecting alanine aminotransferase(ALT) and aspartate aminotransferase(AST) levels in the plasma and H&E staining in liver tissues of mice. The malondialdehyde(MDA) and glutathione(GSH) content and catalase(CAT) activity in mouse liver tissues were detected to evaluate the effect of AO-Ⅰ on APAP-induced oxidative stress in the liver. The proteins in the liver p38 mitogen-activated protein kinase(p38 MAPK), c-jun N-terminal kinase(JNK), and nuclear factor kappa-B p65(NF-κB p65) signaling pathways were measured by Western blot, and the liver inflammatory cytokines interleukin-1β(IL-1β) and interleukin-6(IL-6) were detected by real-time PCR. Compared with the APAP group, the combination groups showed reduced APAP-induced ALT level and liver MDA content, potentiated liver CAT activity, and elevated GSH content. Mechanistically, AO-Ⅰ treatment significantly inhibited APAP-up-regulated MAPK phosphorylation and NF-κB p65, and significantly reduced the transcriptional activities of IL-1β and IL-6, downstream targets of NF-κB p65. AO-Ⅰ can improve APAP-induced ALI and the underlying mechanism is related to the inhibition of the MAPK/NF-κB p65 signaling pathway in APAP-challenged mice.
Acetaminophen/adverse effects* ; Animals ; Chemical and Drug Induced Liver Injury/drug therapy* ; Lactones ; Mice ; NF-kappa B/metabolism* ; Sesquiterpenes ; Signal Transduction

The present study investigated the mechanism of the Tibetan medicine Ershiwuwei Songshi Pills(ESP) against the liver injury induced by acetaminophen(APAP) in mice based on the kelch-like ECH-associated protein 1(Keap1)/nuclear transcription factor E2 related factor 2(Nrf2) and Toll-like receptor 4(TLR4)/nuclear factor-kappa B(NF-κB) p65 signaling pathways. Kunming mice were randomly divided into a blank control group, a model group, an N-acetyl-L-cysteine(NAC) group, and high-(400 mg·kg~(-1)), medium-(200 mg·kg~(-1)), and low-dose(100 mg·kg~(-1)) ESP groups. After 14 days of continuous administration, except for those in the control group, the mice were intraperitoneally injected with 200 mg·kg~(-1) APAP. After 12 h, the serum and liver tissues of mice were collected. Hematoxylin-eosin(HE) staining was performed on pathological sections of the liver, and the levels of aspartate aminotransferase(AST) and alanine aminotransferase(ALT) in the serum and the levels of glutathione(GSH), malondialdehyde(MDA), superoxide dismutase(SOD), catalase(CAT), myeloperoxidase(MPO), and total antioxidant capacity(T-AOC) in liver tissue homogenate were detected to observe and analyze the protective effect of ESP on APAP-induced liver injury in mice. The serum levels of tumor necrosis factor-alpha(TNF-α), interleukin-1 beta(IL-1β), and interleukin-6(IL-6) were determined by enzyme-linked immunosorbent assay(ELISA). The protein expression of Nrf2, Keap1, TLR4, and NF-κB p65 in the liver was determined by Western blot. Quantitative real-time was used to determine the mRNA expression of glutamate-cysteine ligase catalytic subunit(GCLC), glutamate-cysteine ligase regulatory subunit(GCLM), heme oxygenase-1(HO-1), and NAD(P)H dehydrogenase quinone 1(NQO-1) in the liver to explore the mechanism of ESP in improving APAP-induced liver damage in mice. As revealed by results, compared with the model group, the ESP groups showed improved liver pathological damage, decreased ALT and AST levels in the serum and MDA and MPO content in the liver, increased GSH, SOD, CAT, and T-AOC in the liver, reduced TNF-α and IL-6 levels in the serum, down-regulated expression of Keap1 in the liver cytoplasm and NF-κB p65 in the liver nucleus, up-regulated expression of Nrf2 in the liver nucleus, insignificant change in TLR4 expression, and elevated relative mRNA expression levels of antioxidant genes GCLC, GCLM, HO-1, and NQO-1. ESP can reduce the oxidative damage and inflammation caused by APAP, and the mechanism may be related to the Keap1/Nrf2 signaling pathway and the signal transduction factors on the TLR4/NF-κB p65 pathway.
Acetaminophen/toxicity* ; Animals ; Antioxidants/pharmacology* ; Glutamate-Cysteine Ligase/pharmacology* ; Glutathione ; Interleukin-6/metabolism* ; Kelch-Like ECH-Associated Protein 1/metabolism* ; Liver ; Medicine, Tibetan Traditional ; Mice ; NF-E2-Related Factor 2/metabolism* ; NF-kappa B/metabolism* ; RNA, Messenger/metabolism* ; Signal Transduction ; Superoxide Dismutase/metabolism* ; Toll-Like Receptor 4/metabolism* ; Tumor Necrosis Factor-alpha/metabolism*

Acetaminophen, also known as N-acetyl-p-aminophenol (APAP), is commonly used as an antipyretic and analgesic agent. APAP overdose can induce hepatic toxicity, known as acetaminophen-induced liver injury (AILI). However, therapeutic doses of APAP can also induce AILI in patients with excessive alcohol intake or who are fasting. Hence, there is a need to understand the potential pathological mechanisms underlying AILI. In this review, we summarize three main mechanisms involved in the pathogenesis of AILI: hepatocyte necrosis, sterile inflammation, and hepatocyte regeneration. The relevant factors are elucidated and discussed. For instance, N-acetyl-p-benzoquinone imine (NAPQI) protein adducts trigger mitochondrial oxidative/nitrosative stress during hepatocyte necrosis, danger-associated molecular patterns (DAMPs) are released to elicit sterile inflammation, and certain growth factors contribute to liver regeneration. Finally, we describe the current potential treatment options for AILI patients and promising novel strategies available to researchers and pharmacists. This review provides a clearer understanding of AILI-related mechanisms to guide drug screening and selection for the clinical treatment of AILI patients in the future.
Acetaminophen/toxicity* ; Analgesics, Non-Narcotic/toxicity* ; Animals ; Chemical and Drug Induced Liver Injury/pathology* ; Chemical and Drug Induced Liver Injury, Chronic/pathology* ; Humans ; Inflammation/metabolism* ; Liver/pathology* ; Mice ; Mice, Inbred C57BL ; Necrosis/pathology*

Salvianolic acid B(Sal B), tanshinone Ⅱ_A(TSN Ⅱ_A), and glycyrrhetinic acid(GA) lipid emulsion(GTS-LE) was prepared by the high-speed dispersion method combined with ultrasonic emulsification.The preparation process of the emulsion was optimized by single-factor method and D-optimal method with appearance, centrifugal stability, and particle size of the emulsion as evalua-tion indexes, followed by verification.In vitro release of Sal B, TSN Ⅱ_A, and GA in GTS-LE was performed by reverse dialysis.In vivo pharmacokinetic evaluation was carried out in mice.The acute liver injury model was induced by acetaminophen.The effect of oral GTS-LE on the acute liver injury was investigated by serum liver function indexes and pathological changes in liver tissues of mice.The results showed that under the optimal preparation process, the average particle size of GTS-LE was(145.4±9.25) nm and the Zeta potential was(-33.6±1.45) mV.The drug-loading efficiencies of Sal B, TSN Ⅱ_A, and GA in GTS-LE were above 95%, and the drug release in vitro conformed to the Higuchi equation.The pharmacokinetic results showed that the C_(max) of Sal B, TSN Ⅱ_A, and GA in GTS-LE was 3.128, 2.7, and 2.85 times that of the GTS-S group, and AUC_(0-t) of Sal B, TSN Ⅱ_A, and GA in GTS-LE was 3.09, 2.23, and 1.9 times that of the GTS-S group.After intragastric administration of GTS-LE, the activities of alanine aminotransferase and aspartate aminotransferase were significantly inhibited, the content of malondialdehyde was reduced, and the structure of hepatocytes recovered to normal.In conclusion, GTS-LE can delay the release of Sal B and promote the release of TSN Ⅱ_A and GA.The encapsulation of three drug components in the emulsion can improve the oral bioavailability to varying degrees and can effectively prevent the acute liver injury caused by acetaminophen.
Abietanes/therapeutic use* ; Acetaminophen/therapeutic use* ; Alanine Transaminase/metabolism* ; Animals ; Antipyretics/therapeutic use* ; Aspartate Aminotransferases/metabolism* ; Benzofurans/therapeutic use* ; Chemical and Drug Induced Liver Injury/prevention & control* ; Depsides/therapeutic use* ; Emulsions ; Glycyrrhetinic Acid/therapeutic use* ; Liver/drug effects* ; Malondialdehyde ; Mice

Excess acetaminophen(APAP) can be converted by the cytochrome P450 system to the toxic metabolite N-acetyl-p-benzoquinoneimine(NAPQI), which consumes glutathione(GSH). When GSH is depleted, NAPQI covalently binds with proteins, inducing mitochondrial dysfunction and oxidative stress and thereby leading to hepatotoxicity. Schisandrin C(SinC) is a dibenzocyclooctadiene derivative isolated from Schisandra chinensis. Although there is some evidence showing that SinC has hepatoprotective activity, its protective effect and mechanism on APAP-induced liver injury remain unclear. In this paper, an acute liver injury mouse model was established by intraperitoneal injection of APAP at a dose of 400 mg·kg~(-1) to evaluate the effect of SinC administration on the APAP-induced liver injury and its mechanism through an animal experiment. At the same time, a potential candidate drug was provi-ded for traditional Chinese medicine(TCM) prevention and treatment of overdose APAP-induced liver injury. In the APAP-induced liver injury mouse model, we found that SinC can relieve hepatic histopathological lesions and significantly reduce the activities of alanine aminotransferase(ALT), aspartate aminotransferase(AST) and alkaline phosphatase(ALP). It was also capable of increasing the content of GSH and superoxide dismutase(SOD) and decreasing the levels of total bilirubin(TBIL), direct bilirubin(DBIL), malondialdehyde(MDA), interleukin-6(IL-6) and tumor necrosis factor-α(TNF-α). Further analysis showed that SinC decreased the content of CYP2 E1 in liver tissues at protein and mRNA levels and increased nuclear factor erythroid 2-related factor 2(Nrf2) and the expression of its downstream targets(including HO-1, NQO1 and GCLC). Taken together, the above results indicate that SinC can alleviate APAP-induced liver injury by reducing the expression of CYP2 E1, suppressing apoptosis, improving inflammatory response and activating the Nrf2 signaling pathway to inhibit oxidative stress.
Mice ; Animals ; Acetaminophen/toxicity* ; NF-E2-Related Factor 2/metabolism* ; Chemical and Drug Induced Liver Injury/pathology* ; Chemical and Drug Induced Liver Injury, Chronic/pathology* ; Liver ; Signal Transduction ; Oxidative Stress ; Bilirubin/metabolism*

OBJECITVIE: To compare the liver protective activity of fresh/dried dandelion extracts against acetaminophen (APAP)-induced hepatotoxicity. METHODS: Totally 90 Kunming mice were randomly divided into 10 groups according to body weight (9 mice for each group). The mice in the normal control and model (vehicle control) groups were administered sodium carboxymethyl cellulose (CMC-Na, 0.5%) only. Administration groups were pretreated with high and low-dose dry dandelion extract (1,000 or 500 g fresh herb dried and then decocted into 120 mL solution, DDE-H and DDE-L); low-, medium- and high-dose dandelion juice (250, 500, 1,000 g/120 mL, DJ-L, DJ-M, and DJ-H); fresh dandelions evaporation juice water (120 mL, DEJW); dry dandelion extract dissolved by pure water (1 kg/120 mL, DDED-PW); dry dandelion extract dissolved by DEJW (120 g/120 mL, DDED-DEJW) by oral gavage for 7 days at the dosage of 0.5 mL solution/10 g body weight; after that, except normal control group, all other groups were intraperitonealy injected with 350 mg/kg APAP to induce liver injury. Twenty hours after APAP administration, serum and liver tissue were collected and serum alanine aminotransferase (AST), aspartate transaminase (ALT), alkaline phosphatase (AKP), malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD) activities were quantified by biochemical kits; tumor necrosis factor (TNF-α), interleukin (IL)-2, and IL-1 β contents in liver tissue were determined by enzyme linked immunosorbent assay kits. Histopathological changes in liver tissues were observed by hematoxylin and eosin staining; TUNEL Assay and Hoechst 33258 staining were applied for cell apoptosis evaluation. The expressions of heme oxygenase-1 (HO-1), nuclear factor erythroid-2-related factor 2 (Nrf-2), caspase-9, B-cell leukemia/lymphoma 2 (Bcl-2), Bax and p-JNK were determined by Western blot analysis. RESULTS: Pretreatment with fresh dandelion juice (FDJ, including DJ-L, DJ-M, DJ-H, DEJW and DDED-DEJW) significantly decreased the levels of serum ALT, AST, AKP, TNF-α and IL-1β compared with vehicle control group (P<0.05 or P<0.01). Additionally, compared with the vehicle control group, FDJ decreased the levels of hepatic MDA and restored GSH levels and SOD activity in livers (P<0.05 or P<0.01). FDJ inhibited the overexpression of pro-inflammatory factors including cyclooxygenase-2 and inducible nitric oxide synthase in the liver tissues (P<0.05 or P<0.01). Furthermore, Western blot analysis revealed that FDJ pretreatment inhibited activation of apoptotic signaling pathways via decreasing of Bax, and caspase-9 and JNK protein expression, and inhibited activation of JNK pathway (P<0.05 or P<0.01). Liver histopathological observation provided further evidence that FDJ pretreatment significantly inhibited APAP-induced hepatocyte necrosis, inflammatory cell infiltration and congestion. CONCLUSIONS FDJ pretreatment protects against APAP-induced hepatic injury by activating the Nrf-2/HO-1 pathway and inhibition of the intrinsic apoptosis pathway, and the effect of fresh dandelion extracts was superior to dried dandelion extracts in APAP hepatotoxicity model mice.
Acetaminophen/toxicity* ; Alanine Transaminase ; Animals ; Apoptosis ; Body Weight ; Caspase 9/metabolism* ; Chemical and Drug Induced Liver Injury/prevention & control* ; Dichlorodiphenyl Dichloroethylene/pharmacology* ; Glutathione/metabolism* ; Liver ; Mice ; Oxidative Stress ; Plant Extracts/therapeutic use* ; Superoxide Dismutase/metabolism* ; Taraxacum/metabolism* ; Tumor Necrosis Factor-alpha/metabolism* ; Water/metabolism* ; bcl-2-Associated X Protein/metabolism*

The aim of this study was to observe the protective effect of water extract from Sabia parviflora on mice with acute liver injury induced by acetaminophen, and investigate its possible mechanism. Fifty-eight Kunming mice were divided into 6 groups, 8 in the normal group, 10 in the model group, 10 in the biphenyl diester group, and 10 each in the low, medium and high dose groups. After adaptive feeding for one week, the mice in normal group were intragastrically administered with an equal volume of 0.5% sodium carboxymethylcellulose sodium(CMC-Na), and the mice in other groups were intragastrically administered with corresponding drugs at 20 mL·kg~(-1) once a day. Then acetaminophen(200 mg·kg~(-1)) was administered after the above drug administration except the normal group. The behavior and signs of the experimental animals were observed every day and the samples were taken for experiments on the next day of the final administration. The liver mass and mass index were calculated. The blood was collected from the abdominal aorta and centrifuged to obtain the serum for detecting aspartate aminotransferase(AST) activity and alanine aminotransferase(ALT) activity. The liver tissue homogenate was used to detect superoxide dismutase(SOD) activity, glutathione(glutathione, r-glutamyl cysteingl+glycine, GSH) activity and malondialdehyde(MDA) content. Liver tissue was analyzed for histological analysis. The results showed that S. parviflora could alleviate the lipid peroxidation damage in the liver caused by acetaminophen, reduce the ALT and AST activities in serum, increase the levels of SOD and GSH in liver tissue, decrease the content of MDA in liver tissue, and inhibit the apoptosis. S. parviflora could also improve the live histopathological profile, protect liver cells and restore liver function. Among them, the high dose had the most significant effect and showed dose-effect relationship. This study indicated that S. parviflora had a significant protective effect on acetaminophen-induced liver injury in mice, and its mechanism may be related to its anti-oxidation effect and inhi-bitory effect on apoptosis.
Acetaminophen/toxicity* ; Alanine Transaminase/metabolism* ; Animals ; Aspartate Aminotransferases/metabolism* ; Chemical and Drug Induced Liver Injury/drug therapy* ; Liver/enzymology* ; Malondialdehyde/analysis* ; Mice ; Oxidative Stress ; Plant Extracts/pharmacology* ; Superoxide Dismutase/metabolism*

The present study was designed to evaluate protective activity of an ethanol extract of the stems of Schisandra chinensis (SCE) and explore its possible molecular mechanisms on acetaminophen (APAP) induced hepatotoxicity in a mouse model. The results of HPLC analysis showed that the main components of SCE included schisandrol A, schisandrol B, deoxyschisandrin, schisandrin B, and schisandrin C and their contents were 5.83, 7.11, 2.13, 4.86, 0.42 mg·g, respectively. SCE extract was given for 7 consecutive days before a single hepatotoxic dose of APAP (250 mg·kg) was injected to mice. Our results showed that SCE pretreatment ameliorated liver dysfunction and oxidative stress, which was evidenced by significant decreases in aspartate transaminase (AST), alanine aminotransferase (ALT), malondialdehyde (MDA) contents and elevations in reduced glutathione (GSH) and superoxide dismutase (SOD) levels. These findings were associated with the result that the SCE pretreatment significantly decreased expression levels of 4-hydroxynonenal (4-HNE) and 3-nitrotyrosine (3-NT). SCE also significantly decreased the expression levels of Bax, mitogen- activated protein kinase (MAPK), and cleaved caspase-3 by APAP exposure. Furthermore, supplementation with SCE suppressed the expression levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), suggesting alleviation of inflammatory response. In summary, these findings from the present study clearly demonstrated that SCE exerted significant alleviation in APAP-induced oxidative stress, inflammation and apoptosis mainly via regulating MAPK and caspase-3 signaling pathways.
Acetaminophen ; adverse effects ; Alanine Transaminase ; metabolism ; Animals ; Apoptosis ; drug effects ; Aspartate Aminotransferases ; metabolism ; Caspase 3 ; genetics ; metabolism ; Chemical and Drug Induced Liver Injury ; genetics ; metabolism ; physiopathology ; prevention & control ; Drugs, Chinese Herbal ; administration & dosage ; chemistry ; Glutathione ; metabolism ; Humans ; Liver ; drug effects ; metabolism ; Male ; Malondialdehyde ; metabolism ; Mice ; Mice, Inbred ICR ; Mitogen-Activated Protein Kinases ; chemistry ; genetics ; metabolism ; Oxidative Stress ; drug effects ; Schisandra ; chemistry ; Signal Transduction ; drug effects