CysLTR1 Blockage Ameliorates Liver Injury Caused by Aluminum-Overload via PI3K/AKT/mTOR-Mediated Autophagy Activation in Vivo and in Vitro

Fermented Ginsenosides Alleviate Acute Liver Injury Induced by CCl4 in Mice by Regulating the AKT/mTOR Signaling Pathway

This study investigated the alleviating effect of fermented ginsenosides obtained through yeast strain fermentation transformation on acute liver injury (ALI) induced by CCl4. Strains were screened for their ability to produce β-glucosidase, the transformation ability of the strain was verified by high-performance liquid chromatography, and the Saccharomyces cerevisiae strain F6 was obtained by 26S rRNA sequencing. After fermentation by F6 strain, it was found that the content of ginsenosides Re, Rb1, and Rb2 was significantly decreased (P < 0.05), and rare ginsenosides were detected, with the content of Rh4 and Rg5 reaching 2.65 mg·g-1 and 2.56 mg·g-1. We also explored the preventive effect of fermented ginsenoside extract (FGE) on ALI. Mice were evenly divided into 9 groups as follows: control group, ALI model group, positive drug bifendate group, and treatment group, which included 3 ginsenoside extract (GE) groups and 3 FGE groups (dosage of 150, 300, and 450 mg·kg-1 b.w.). The results showed that compared with the ALI model group, FGE significantly increased the levels of glutathione peroxidase, hydroperoxidase, and superoxide dismutase and also decreased the malondialdehyde level. The levels of alanine aminotransferase, aspartate aminotransferase, and total bilirubin markers were significantly reduced, and the levels of inflammatory cytokines TNF-α, IL-6, and IL-1β were significantly decreased. Bioinformatics analysis combined with Western blot validation explored the molecular mechanism of the effect of FGE. It was found that FGE could downregulate the expression of the p-AKT/AKT and the p-mTOR/mTOR ratios. These results suggested that FGE played an alleviative role in ALI by promoting autophagy to inhibit the AKT/mTOR signaling pathway.

Hepatoprotective efficacy and interventional mechanism of JianPi LiShi YangGan formula in acute-on-chronic liver failure

ETHNOPHARMACOLOGICAL RELEVANCE

Acute-on-chronic liver failure (ACLF) progresses rapidly with a high short-term death rate. Although JianPi LiShi YangGan formula (YGF) has been used to treat ACLF by managing inflammatory responses and reducing endotoxemia, hepatocyte injury, and mortality, the underlying mechanisms remain unclear.

AIM OF THE STUDY

This study aims to investigate the potential mechanisms underlying the efficacy and protective benefits of YGF in mice with ACLF.

MATERIALS AND METHODS

YGF composition was determined using high-performance liquid chromatography coupled with mass spectrometry. We constructed a mouse model of ACLF using carbon tetrachloride, lipopolysaccharide (LPS), and D-galactosamine (D-Gal), as well as an in vitro model of D-Gal/LPS-induced hepatocyte injury. The therapeutic effects of YGF in ACLF mice were verified using hematoxylin-eosin, Sirius red, and Masson staining, and by measuring serum alanine transaminase (ALT), aspartate transaminase (AST), and inflammatory cytokine levels. Mitochondrial damage in hepatocytes was evaluated using electron microscopy, while superoxide anion levels in liver tissue were investigated using dihydroethidium. Transcriptome analysis, immunohistochemistry, western blotting, and immunofluorescence assays were performed to explore the mechanisms underlying the ameliorative effects of YGF against ACLF.

RESULTS

In mice with ACLF, YGF therapy partially decreased serum inflammatory cytokine levels, as well as hepatocyte injury and liver fibrosis. The livers of ACLF mice treated with YGF exhibited decreased mitochondrial damage and reactive oxygen species generation, as well as a decreased number of M1 macrophages and increased number of M2 macrophages. Transcriptome analysis revealed that YGF may regulate biological processes such as autophagy, mitophagy, and PI3K/AKT signaling. In ACLF mice, YGF promoted mitophagy and inhibited PI3K/AKT/mTOR pathway activation in hepatocytes. Meanwhile, the autophagy inhibitor 3M-A reduced the capacity of YGF to induce autophagy and protect against hepatocyte injury in vitro. In contrast, the PI3K agonist 740 Y-P suppressed the ability of YGF to control PI3K/AKT/mTOR pathway activation and induce autophagy.

CONCLUSIONS

Together, our findings suggest that YGF mediates autophagy, tight junctions, cytokine generation, and other biological processes. In addition, YGF inhibits hepatic inflammatory responses and ameliorates hepatocyte injury in mice with ACLF. Mechanistically, YGF can promote mitophagy to ameliorate acute-on-chronic liver failure by inhibiting the PI3K/AKT/mTOR pathway.

Inhibition of CysLTR1 reduces the levels of aggregated proteins in retinal pigment epithelial cells

The endosomal-lysosomal system (ELS), which carries out cellular processes such as cellular waste degradation via autophagy, is essential for cell homeostasis. ELS inefficiency leads to augmented levels of damaged organelles and intracellular deposits. Consequently, the modulation of autophagic flux has been recognized as target to remove damaging cell waste. Recently, we showed that cysteinyl leukotriene receptor 1 (CysLTR1) antagonist application increases the autophagic flux in the retinal pigment epithelial cell line ARPE-19. Consequently, we investigated the effect of CysLTR1 inhibition-driven autophagy induction on aggregated proteins in ARPE-19 cells using flow cytometry analysis. A subset of ARPE-19 cells expressed CysLTR1 on the surface (SE+); these cells showed increased levels of autophagosomes, late endosomes/lysosomes, aggregated proteins, and autophagy as well as decreased reactive oxygen species (ROS) formation. Furthermore, CysLTR1 inhibition for 24 h using the antagonist zafirlukast decreased the quantities of autophagosomes, late endosomes/lysosomes, aggregated proteins and ROS in CysLTR1 SE- and SE+ cells. We concluded that high levels of plasma membrane-localized CysLTR1 indicate an increased amount of aggregated protein, which raises the rate of autophagic flux. Furthermore, CysLTR1 antagonist application potentially mimics the physiological conditions observed in CysLTR1 SE+ cells and can be considered as strategy to dampen cellular aging.

Protective role of thymoquinone in hyperlipidemia-induced liver injury in LDL-R-/-mice

BACKGROUND

Hyperlipidemia, a heterogeneous group of disorders characterized by elevated plasma lipids in the blood, causes severe health problems, leading to fatty liver disease and nonalcoholic fatty liver disease. Thymoquinone, the major active chemical component of Nigella sativa, reportedly exerts a vast array of biological effects. Various studies have reported that Thymoquinone protects against liver injury.

AIMS

The aim of this study was to investigate the possible protective effects of Thymoquinone against liver injury in hyperlipidemia-induced LDL-R-/- mice.

METHODS

Eight-week-old male LDL-R-/- mice were randomly divided into three groups: a control group fed a normal diet and two groups fed a high-cholesterol diet or high-cholesterol diet mixed with Thymoquinone. All groups were fed different diets for 8 weeks. Blood samples were obtained from the inferior vena cava and collected in serum tubes. The samples were then stored at - 80 °C until used. Longitudinal sections of liver tissues were fixed in 10% formalin and then embedded in paraffin for histological evaluation. The remainder of the liver tissues were snap-frozen in liquid nitrogen for reverse transcription-polymerase chain reaction or western blotting.

RESULTS

Our results demonstrated that Thymoquinone administration significantly reduced liver histological alterations by hyperlipidemia. Thymoquinone mitigated hyperlipidemia-induced liver injury as indicated by the suppression of metabolic characteristics, liver biochemical parameters, pyroptosis indicators, a macrophage marker, and the phosphatidylinositide 3-kinase signaling pathway.

CONCLUSIONS

Thymoquinone is a potential therapeutic agent for hyperlipidemia-induced liver injury.

Recent insights into autophagy and metals/nanoparticles exposure

Some anthropogenic pollutants, such as heavy metals and nanoparticles (NPs), are widely distributed and a major threat to environmental safety and public health. In particular, lead (Pb), cadmium (Cd), chromium (Cr), arsenic (As), and mercury (Hg) have systemic toxicity even at extremely low concentrations, so they are listed as priority metals in relation to their significant public health burden. Aluminum (Al) is also toxic to multiple organs and is linked to Alzheimer's disease. As the utilization of many metal nanoparticles (MNPs) gradually gain traction in industrial and medical applications, they are increasingly being investigated to address potential toxicity by impairing certain biological barriers. The dominant toxic mechanism of these metals and MNPs is the induction of oxidative stress, which subsequently triggers lipid peroxidation, protein modification, and DNA damage. Notably, a growing body of research has revealed the linkage between dysregulated autophagy and some diseases, including neurodegenerative diseases and cancers. Among them, some metals or metal mixtures can act as environmental stimuli and disturb basal autophagic activity, which has an underlying adverse health effect. Some studies also revealed that specific autophagy inhibitors or activators could modify the abnormal autophagic flux attributed to continuous exposure to metals. In this review, we have gathered recent data about the contribution of the autophagy/mitophagy mediated toxic effects and focused on the involvement of some key regulatory factors of autophagic signaling during exposure to selected metals, metal mixtures, as well as MNPs in the real world. Besides this, we summarized the potential significance of interactions between autophagy and excessive reactive oxygen species (ROS)-mediated oxidative damage in the regulation of cell survival response to metals/NPs. A critical view is given on the application of autophagy activators/inhibitors to modulate the systematic toxicity of various metals/MNPs.

Montelukast prevents mice against carbon tetrachloride- and methionine-choline deficient diet-induced liver fibrosis: Reducing hepatic stellate cell activation and inflammation

AIMS

Montelukast is an antagonist of cysteinyl leukotriene receptor 1 (CysLTR1) that protects against inflammation and oxidative stress. However, the function of montelukast in liver fibrosis remains unknown. In this study, we examined whether the pharmacological inhibition of CysLTR1 could protect mice against hepatic fibrosis.

MATERIALS AND METHODS

Carbon tetrachloride (CCl₄) and methionine-choline deficient (MCD) diet models were used in this study. The expression of CysLTR1 in liver were detected by RT-qPCR and Western blot analysis. Liver hydroxyproline levels, fibrotic genes expression, serum biochemical indexes and inflammatory factors were used to evaluate the effect of montelukast on liver fibrosis, injury, and inflammation. In vitro, we used the RT-qPCR and Western blot analysis to assess CysLTR1 in mouse primary hepatic stellate cell (HSC) and human LX-2 cell line. The role of montelukast on HSC activation and the underlying mechaisms were determined using RT-qPCR analysis, Western blot and immunostaining assays.

KEY FINDINGS

Chronic stimulation from CCl₄ and MCD diet upregulated the mRNA and protein levels of CysLTR1 in the liver. Pharmacological inhibition of CysLTR1 by montelukast ameliorated liver inflammation and fibrosis in both models. Mechanistically, montelukast suppressed HSC activation by targeting the TGFβ/Smad pathway in vitro. The hepatoprotective effect of montelukast was also associated with reduced liver injury and inflammation.

SIGNIFICANCE

Montelukast suppressed CCl₄- and MCD-induced chronic hepatic inflammation and liver fibrosis. CysLTR1 might be a therapeutic target for treating liver fibrosis.

Leukotriene Signaling as a Target in α-Synucleinopathies

Parkinson’s disease (PD) and dementia with Lewy bodies (DLB) are two common types of α-synucleinopathies and represent a high unmet medical need. Despite diverging clinical manifestations, both neurodegenerative diseases share several facets of their complex pathophysiology. Apart from α-synuclein aggregation, an impairment of mitochondrial functions, defective protein clearance systems and excessive inflammatory responses are consistently observed in the brains of PD as well as DLB patients. Leukotrienes are lipid mediators of inflammatory signaling traditionally known for their role in asthma. However, recent research advances highlight a possible contribution of leukotrienes, along with their rate-limiting synthesis enzyme 5-lipoxygenase, in the pathogenesis of central nervous system disorders. This review provides an overview of in vitro as well as in vivo studies, in summary suggesting that dysregulated leukotriene signaling is involved in the pathological processes underlying PD and DLB. In addition, we discuss how the leukotriene signaling pathway could serve as a future drug target for the therapy of PD and DLB.

Design, Synthesis, Biological Evaluation, and Molecular Modeling of 2-Difluoromethylbenzimidazole Derivatives as Potential PI3Kα Inhibitors

PI3Kα is one of the potential targets for novel anticancer drugs. In this study, a series of 2-difluoromethylbenzimidazole derivatives were studied based on the combination of molecular modeling techniques 3D-QSAR, molecular docking, and molecular dynamics. The results showed that the best comparative molecular field analysis (CoMFA) model had q2 = 0.797 and r2 = 0.996 and the best comparative molecular similarity indices analysis (CoMSIA) model had q2 = 0.567 and r2 = 0.960. It was indicated that these 3D-QSAR models have good verification and excellent prediction capabilities. The binding mode of the compound 29 and 4YKN was explored using molecular docking and a molecular dynamics simulation. Ultimately, five new PI3Kα inhibitors were designed and screened by these models. Then, two of them (86, 87) were selected to be synthesized and biologically evaluated, with a satisfying result (22.8 nM for 86 and 33.6 nM for 87).

Unraveling the molecular mechanisms of hyperlipidemia using integrated lncRNA and mRNA microarray data

Long non-coding RNAs (lncRNAs) have key roles in various diseases; however, their functions in hyperlipidemia (HLP) have remained elusive. In the present study, microarray technology was utilized to analyze the differential expression of lncRNAs and mRNAs in liver tissues of apolipoprotein E^-/- mice as a model of HLP compared with control mice. A total of 104 and 96 differentially expressed lncRNAs and mRNAs, respectively, were identified. Differentially expressed genes were significantly enriched in biological processes such as nitric oxide biosynthesis, innate immune response and inflammatory response. Finally, two pairs of target genes and 38 transcription factors with regulatory functions in HLP were predicted based on the lncRNA and mRNA co-expression network. The lncRNA expression profile was significantly altered in liver tissues of the mouse model of HLP and may provide novel targets for research into treatments.

Liquiritigenin protects against arsenic trioxide-induced liver injury by inhibiting oxidative stress and enhancing mTOR-mediated autophagy

Liquiritigenin (LQ) has protective effects against various hepatotoxicities. However, its specific role on arsenic trioxide (ATO)-induced hepatotoxicity and the related biomolecular mechanisms remain unclear. The purpose of this study is to explore the protective actions of LQ on ATO-induced hepatotoxicity and its biomolecular mechanisms in mice. LQ was administered orally at 20 and 40 mg/kg per day for seven consecutive days with an intraperitoneal injection of ATO (5 mg/kg). Liver injury was induced by ATO and was alleviated by treatment with LQ as reflected by reduced histopathological damage of liver and decreased serum ALT, AST, and ALP levels. The generation of intracellular ROS induced by ATO was attenuated after LQ treatment. The levels of SOD, CAT, and GSH were elevated with LQ administration while MDA levels decreased. LQ mitigated elevated TNF-α and IL-6 levels as well as the hepatic mitochondrial damage caused by ATO. Moreover, LQ upregulated the expression of LC3-II and enhanced autophagy in the liver of ATO-induced mice. Further studies indicated that LQ significantly suppressed the expression of p-PI3K, p-AKT, and p-mTOR in ATO-induced mice. In conclusion, our findings show that LQ protects against ATO-induced hepatotoxicity due to its antioxidant and anti-inflammatory activities and enhancement of autophagy mediated by the PI3K/AKT/mTOR signaling pathway in mice.

Modulation of autophagy and transient receptor potential vanilloid 4 channels by montelukast in a rat model of hemorrhagic cystitis

AIMS

Hemorrhagic cystitis (HC) is a major urotoxic complication of cyclophosphamide (CPA) therapy. This study investigated the uroprotective effect of montelukast on CPA-induced HC, compared to the efficacy of 2-mercaptoethane sulfonate sodium (MESNA).

MAIN METHODS

Male albino rats were pretreated with MESNA (40 mg/kg/day, IP) or montelukast (10 mg/kg/day, orally) for three days then received a single dose of CPA (200 mg/kg, IP), 1 h after the last dose, and compared to CPA-treated rats receiving drug vehicle. Age-matched rats were used as controls. Bladders of rats were assessed biochemically, macroscopically and microscopically by light and electron microscope 24 h later.

KEY FINDINGS

CPA injection contributed to increased bladder weight, urothelial ulceration, vascular congestion, hemorrhage, increased collagen deposition and mast cell infiltration, compared to control rats. Montelukast preconditioning suppressed mast cell infiltration and inflammatory mediators to greater extent than MESNA. Also, montelukast enhanced autophagosomes formation in detrusor myocytes and up-regulated the autophagy-related proteins (beclin-1 & LC3-II), likely through inhibition of phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling pathway. Montelukast preconditioning offset the up-regulation of transient receptor potential vanilloid 4 (TRPV4) in urothelial tissue of CPA-treated rats, to greater extent than MESNA.

SIGNIFICANCE

These results demonstrate the uroprotective effect of montelukast on CPA-induced HC, which appears to be more superior to MESNA. These findings suggest that montelukast can emerge as a novel strategy to protect against CPA-induced urotoxicity.

Classification models and SAR analysis on CysLT1 receptor antagonists using machine learning algorithms

Cysteinyl leukotrienes 1 (CysLT1) receptor is a promising drug target for rhinitis or other allergic diseases. In our study, we built classification models to predict bioactivities of CysLT1 receptor antagonists. We built a dataset with 503 CysLT1 receptor antagonists which were divided into two groups: highly active molecules (IC₅₀ < 1000 nM) and weakly active molecules (IC₅₀ ≥ 1000 nM). The molecules were characterized by several descriptors including CORINA descriptors, MACCS fingerprints, Morgan fingerprint and molecular SMILES. For CORINA descriptors and two types of fingerprints, we used the random forests (RF) and deep neural networks (DNN) to build models. For molecular SMILES, we used recurrent neural networks (RNN) with the self-attention to build models. The accuracies of test sets for all models reached 85%, and the accuracy of the best model (Model 2C) was 93%. In addition, we made structure-activity relationship (SAR) analyses on CysLT1 receptor antagonists, which were based on the output from the random forest models and RNN model. It was found that highly active antagonists usually contained the common substructures such as tetrazoles, indoles and quinolines. These substructures may improve the bioactivity of the CysLT1 receptor antagonists.

Zafirlukast prevented ox-LDL-induced formation of foam cells

Atherosclerosis (AS), a common arterial disease, is one of the main pathological roots of cardiovascular disease. The formation and accumulation of foam cells is an important event in early AS. An imbalance between cholesterol uptake and efflux is the primary cause of foam cell formation. Although research has focused on preventing the formation of foam cells, a safe and effective therapy has to be found. Zafirlukast is a widely useful type 1 cysteinyl leukotriene receptor (CysLT1R) antagonist with a good safety profile. Zafirlukast is the most used for the treatment of asthma and allergic rhinitis. However, the effect of zafirlukast on preventing the formation of foam cells has not been determined. The aim of this study was to investigate whether zafirlukast prevented macrophages from transforming into foam cells. Our data show that zafirlukast reduced the expression of CD36 and lipoprotein receptor-1 (LOX-1), which are responsible for lipid uptake. In addition, zafirlukast enhanced the activity of ATP-Binding Cassette A1 (ABCA1) and ATP-binding cassette transporter G1 (ABCG1), leading to the acceleration of cholesterol efflux. Furthermore, zafirlukast influenced the activity of the phosphatidylinositol-3-kinase (PI3K)/Akt signaling pathway, which mediates the expression of ABCA1 and ABCG1. In summary, our data indicate that zafirlukast might be a potential treatment strategy for AS by mediating lipid metabolism and preventing the formation of foam cells.

Cysteinyl leukotriene receptor 1 modulates autophagic activity in retinal pigment epithelial cells

The retinal pigment epithelium (RPE), which is among the tissues in the body that are exposed to the highest levels of phagocytosis and oxidative stress, is dependent on autophagy function. Impaired autophagy and continuous cellular stress are associated with various disorders, such as dry age-related macular degeneration (AMD), a disease for which effective therapies are lacking. Cysteinyl leukotriene receptor (CysLTR) 1 is a potential modulator of autophagy; thus, the aim of this study was to investigate the role of CysLTR1 in autophagy regulation in the RPE cell line ARPE-19. The polarized ARPE-19 monolayer exhibited expression of CysLTR1, which was colocalized with β-tubulin III. In ARPE-19 cells, autophagic activity was rhythmically regulated and was increased upon CysLTR1 inhibition by Zafirlukast (ZK) treatment. H₂O₂ affected the proautophagic regulatory effect of ZK treatment depending on whether it was applied simultaneously with or prior to ZK treatment. Furthermore, mRNA levels of genes related to the leukotriene system, autophagy and the unfolded protein response were positively correlated. As CysLTR1 is involved in autophagy regulation under basal and oxidative stress conditions, a dysfunctional leukotriene system could negatively affect RPE functions. Therefore, CysLTR1 is a potential target for new treatment approaches for neurodegenerative disorders, such as AMD.

Flavonoids ameliorate aluminum chloride-induced learning and memory impairments via suppression of apoptosis and oxidative stress in rats

The study was to investigate the effects of flavonoids (rutin, puerarin, and silymarin) on learning and memory function in rats exposed to aluminum chloride (AlCl₃). Wistar rats were administered flavonoids at a dose of 100 mg/(kg·bw)/day or 200 mg/(kg·bw)/day after exposed to 281.40 mg/(kg·bw)/day AlCl₃·6H₂O. The results of Morris water maze suggested that rutin and puerarin increased the frequency of crossing the platform and swimming time spent in the target quadrant of AlCl₃-induced rats significantly. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay indicated that three flavonoids could alleviate apoptosis of hippocampal neurons induced by AlCl₃. Real time-PCR and western blot suggested that rutin, puerarin and 100 mg/(kg·bw)/day silymarin could decrease the AlCl₃-induced high expression of Bcl-2 associated X protein (Bax) mRNA and protein in hippocampus, but the expression of B cell lymphoma/leukemia-2 (Bcl-2) mRNA and protein was not significantly different among groups. Flavonoids could up regulate the low expression of autophagy related proteins (Beclin 1 (Bcl-2-interacting protein with a coiled-coil domain 1) and LC3 (microtubule-associated protein 1 light chain 3)) caused by AlCl₃ exposure. Flavonoids could also adjust the change in adenosine triphosphatase, superoxide dismutase, glutathione peroxidase and malondialdehyde induced by intake of AlCl₃. The results of inductively coupled plasma atomic emission spectroscopy (ICP-AES) suggested that flavonoids could effectively reduce the high Al level in brain and serum of AlCl₃ exposed rats. In conclusion, three flavonoids may improve learning and memory function by inhibiting excessive apoptosis and oxidative stress in AlCl₃ exposed rats.

The Leukotriene Receptor Antagonist Montelukast Reduces Alpha-Synuclein Load and Restores Memory in an Animal Model of Dementia with Lewy Bodies

Dementia with Lewy bodies (DLB) represents a huge medical need as it accounts for up to 30% of all dementia cases, and there is no cure available. The underyling spectrum of pathology is complex and creates a challenge for targeted molecular therapies. We here tested the hypothesis that leukotrienes are involved in the pathology of DLB and that blocking leukotrienes through Montelukast, a leukotriene receptor antagonist and approved anti-asthmatic drug, might alleviate pathology and restore cognitive functions. Expression of 5-lipoxygenase, the rate-limiting enzyme for leukotriene production, was indeed elevated in brains with DLB. Treatment of cognitively deficient human alpha-synuclein overexpressing transgenic mice with Montelukast restored memory. Montelukast treatment resulted in modulation of beclin-1 expression, a marker for autophagy, and in a reduction in the human alpha-synulcein load in the transgenic mice. Reducing the protein aggregation load in neurodegenerative diseases might be a novel model of action of Montelukast. Moreover, this work presents leukotriene signaling as a potential drug target for DLB and shows that Montelukast might be a promising drug candidate for future DLB therapy development.

Integrating serum exosomal microRNA and liver microRNA profiles disclose the function role of autophagy and mechanisms of Fructus Meliae Toosendan-induced hepatotoxicity in mice

Herb-induced liver injury (HILI) is a growing clinical and economic problem worldwide. However, the underlying mechanism of HILI remains largely unknown, which hinders the prevention and treatment of this disease. Recently evidence supports that microRNAs (miRNAs) in circulating exosomes and cells play an important role in the pathology of liver diseases. Thus, using Fructus Meliae Toosendan (FMT) as an example of hepatoxic herbal medicine, the aim of this study was to reveal the mechanisms of FMT-induced liver injury (FILI) through integrated analysis of serum exosomal miRNAs and liver miRNAs profiles on FMT ethyl acetate extract (FMT for short)-exposed mice. Two dosages of FMT (20 and 40 g/kg) were involved in this study, while only high-dose exposure induced obvious liver injury in mice. Pathway analysis of 209 differentially expressed miRNAs (DEMs) in serum exosomes between high-dose FMT and control groups exhibited that FILI might be regulated by apoptosis-related pathways, such as p53 signaling, PI3K/Akt signaling, and PTEN signaling. Integrated analysis of the mRNA targets of serum exosomal DEMs and liver DEMs of high-dose FMT group showed that autophagy was significantly enriched as one of the top canonical pathways in FILI. Hepatocyte apoptosis was then proved by TUNEL assay in the liver tissue of high-dose FMT-treated mice. Moreover, in vivo validation studies suggested that the protein expression levels of PTEN, p-AKT, p53, and BAX were indeed regulated in the mouse liver after high-dose FMT administration, indicating hepatocyte apoptosis may be mediated by these three pathways mentioned above. Intriguingly, PINK1/Parkin-mediated mitophagy was activated in high-dose FMT-treated mouse liver and the protective effect of autophagy in FILI was validated in vitro with an autophagic flux inhibitor. In addition, serum exosomal miR-222, the most downregulated miRNAs between low- and high-dose FMT treatments, might be an important event in the hepatocyte apoptosis by regulating PTEN and PPP2R2A. In conclusion, integrated analysis of microRNA profiles in mouse serum exosomes and liver cells provides insights into the hepatotoxicity mechanisms of FMT and discloses the protective role of autophagy in FILI, suggesting this method could contribute to deeply understand the mechanism of HILI and activation of autophagy may be a potentially therapeutic strategy for FILI even HILI.

Montelukast Prevents Mice Against Acetaminophen-Induced Liver Injury

Acetaminophen (APAP) is a widely used over-the-counter antipyretic and analgesic drug. Overdose of APAP is the leading cause of hospital admission for acute liver failure. Montelukast is an antagonist of cysteinyl leukotriene receptor 1 (Cysltr1), which protects from inflammation and oxidative stress. However, the function of montelukast in APAP-induced hepatotoxicity remains unknown. In this study, we examined whether pharmacological inhibition of Cystlr1 could protect mice against APAP-induced hepatic damage. We found that APAP treatment upregulated messenger RNA and protein levels of Cysltr1 both in vitro and in vivo. Pharmacological inhibition of Cysltr1 by montelukast ameliorated APAP-induced acute liver failure. The hepatoprotective effect of montelukast was associated with upregulation of hepatic glutathione/glutathione disulfide level, reduction in c-Jun-NH2-terminal kinase activation and oxidative stress. In mouse primary hepatocytes, inhibition of Cysltr1 by montelukast ameliorated the expression of inflammatory-related genes and APAP-induced cytotoxicity. We conclude that montelukast may be used to treat APAP-induced acute hepatic injury.

Protective role of thymoquinone in sepsis-induced liver injury in BALB/c mice

Sepsis increases the risk of developing liver injury. Previous studies have demonstrated that thymoquinone (TQ) exhibits hepatoprotective properties in vivo as well as in vitro. The present study aimed to investigate the underlying mechanisms of the protective effects of TQ against liver injury in septic BALB/c mice. Male BALB/c mice (age, 8 weeks) were randomly divided into four groups, namely, the control, TQ (50 mg/kg/day) treatment, cecal ligation and puncture (CLP), and TQ + CLP groups. CLP was performed following gavage of TQ for 2 weeks. At 48 h post-CLP, the histopathological alterations in the liver tissue (LT) and plasma levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) were assessed. The present study evaluated microtubule-associated protein light chain 3 (LC3), sequestosome-1 (p62) and beclin 1 protein expression by western blotting and immunostaining, as well as interleukin (IL)-6, IL-1β, IL-10, monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-α (TNF-α) mRNA expression by RT-qPCR. The results of the present study indicated that administration of TQ to mice reduced the histological alterations caused by CLP in LT. TQ inhibited the plasma levels of ALT, AST and ALP in the CLP group. TQ significantly inhibited the elevation of p62, IL-1β, IL-6, MCP-1 and TNF-α levels as well as increased the LC3, beclin 1 and IL-10 levels in LT. PI3K expression in the TQ + CLP group was significantly decreased compared with that in the CLP group. TQ treatment effectively modulated the expression levels of p62, LC3, beclin 1, PI3K and proinflammatory cytokines, and may be an important agent for the treatment of sepsis-induced liver injury.

Role of Natural Phenolics in Hepatoprotection: A Mechanistic Review and Analysis of Regulatory Network of Associated Genes

The liver is not only involved in metabolism and detoxification, but also participate in innate immune function and thus exposed to frequent target Thus, they are the frequent target of physical injury. Interestingly, liver has the unique ability to regenerate and completely recoup from most acute, non-iterative situation. However, multiple conditions, including viral hepatitis, non-alcoholic fatty liver disease, long term alcohol abuse and chronic use of medications can cause persistent injury in which regenerative capacity eventually becomes dysfunctional resulting in hepatic scaring and cirrhosis. Despite the recent therapeutic advances and significant development of modern medicine, hepatic diseases remain a health problem worldwide. Thus, the search for the new therapeutic agents to treat liver disease is still in demand. Many synthetic drugs have been demonstrated to be strong radical scavengers, but they are also carcinogenic and cause liver damage. Present day various hepatic problems are encountered with number of synthetic and plant based drugs. Nexavar (sorafenib) is a chemotherapeutic medication used to treat advanced renal cell carcinoma associated with several side effects. There are a few effective varieties of herbal preparation like Liv-52, silymarin and Stronger neomin phages (SNMC) against hepatic complications. Plants are the huge repository of bioactive secondary metabolites viz; phenol, flavonoid, alkaloid etc. In this review we will try to present exclusive study on phenolics with its mode of action mitigating liver associated complications. And also its future prospects as new drug lead.

Benzo[a]pyrene induces pyroptotic and autophagic death through inhibiting PI3K/Akt signaling pathway in HL-7702 human normal liver cells

Benzo(α)pyrene (BaP) possesses a forceful hepatotoxicity, and is ubiquitous in foods and ambient air. Our previous study found that BaP induced pyroptotic and autophagic death in HL-7702 human liver cells; the relevant mechanisms, however, remain unknown. This work was therefore to unravel the effects of the PI3K/Akt signaling pathway on pyroptotic and autophagic death triggered by BaP. Cells were treated with or without LY294002 (PI3K/Akt inhibitor) and IGF-1 (PI3K/Akt activator) before BaP exposure, and the results showed that compared with the control, the protein expression of p-Akt was markedly decreased by BaP (p < 0.05). IGF-1 did not subvert this inhibitive effect of BaP, while LY294002 enhanced it. Furthermore, the protein expression of pyroptosis (Cleaved Caspase-1, NO, IL-1β, IL-18), as well as LDH and the relative electrical conductivity were significantly augmented by BaP. The levels of these indices were increased by LY294002 pretreatment, and decreased by IGF-1. Similarly, LY294002 enhanced BaP-induced increase in the key protein expression of autophagy (Beclin-1 and LC3II), while IGF-1 weakened it. Finally, the phosphorylation of FOXO4 was clearly (p < 0.01) inhibited by BaP, and LY294002 suppressed this inhibitive effect of BaP, while IGF-1 strengthened it. In conclusion, BaP was able to induce pyroptotic and autophagic death via blocking the PI3K/Akt signaling pathway in HL-7702 liver cells.

Effect of Puerarin Regulated mTOR Signaling Pathway in Experimental Liver Injury

It is known that excessive hepatocellular apoptosis is a typical characteristic of hepatic disease, and is regulated by the mammalian target of rapamycin (mTOR) signaling pathway. As the main active component of Kudzu (Pueraria lobata) roots, which is frequently used to treat hepatic diseases, Puerarin (Pue) has been reported to alleviate and protect against hepatic injury. However, it is unclear whether Pue can inhibit mTOR signaling to prevent excessive apoptosis in the treatment of hepatic diseases. In the present study, Pue effectively ameliorated pathological injury of the liver, decreased serum enzyme (ALT, AST, γ-GT, AKP, DBIL, and TBIL) levels, regulated the balance between pro-inflammatory (TNF-α, IL-1β, IL-4, IL-6, and TGF-β1) and anti-inflammatory cytokines (IL-10), restored the cell cycle and inhibited hepatocellular apoptosis and caspase-3 expression in rats with liver injury induced by 2-AAF/PH. Pue inhibited p-mTOR, p-AKT and Raptor activity, and increased Rictor expression in the liver tissues of rats with experimental liver injury. These results indicated that Pue effectively regulated the activation of mTOR signaling pathway in the therapeutic and prophylactic process of Pue on experimental liver injury.