ABSTRACT
Cholestasis is a hepatobiliary disorder characterized by the excessive accumulation of toxic bile acids in hepatocytes, leading to cholestatic liver injury (CLI) through multiple pathogenic inflammatory pathways. Currently, there are limited therapeutic options for the management of cholestasis and associated CLI; therefore, new options are urgently needed. Pirfenidone (PF), an oral bioavailable pyridone analog, is used for the treatment of idiopathic pulmonary fibrosis. PF has recently demonstrated diverse potential therapeutic activities against different pathologies. Accordingly, the present study adopted the α-naphthyl isothiocyanate (ANIT)-induced CLI model in mice to explore the potential protective impact of PF and investigate the underlying mechanisms of action. PF intervention markedly reduced the serum levels of ALT, AST, LDH, total bilirubin, and total bile acids, which was accompanied by a remarkable amelioration of histopathological lesions induced by ANIT. PF also protected the mice against ANIT-induced redox imbalance in the liver, represented by reduced MDA levels and elevated GSH and SOD activities. Mechanistically, PF inhibited ANIT-induced downregulated expressions of the farnesoid X receptor (FXR), as well as the bile salt export pump (BSEP) and the multidrug resistance-associated protein 2 (MRP2) bile acid efflux channels. PF further repressed ANIT-induced NF-κB activation and TNF-α and IL-6 production. These beneficial effects were associated with its ability to dose-dependently inhibit Wnt/GSK-3ß/ß-catenin/cyclin D1 signaling. Collectively, PF protects against ANIT-induced CLI in mice, demonstrating powerful antioxidant and anti-inflammatory activities as well as an ability to oppose BA homeostasis disorder. These protective effects are primarily mediated by modulating the interplay between FXR, NF-κB/TNF-α/IL-6, and Wnt/ß-catenin signaling pathways.
Subject(s)
1-Naphthylisothiocyanate , Cholestasis , Glycogen Synthase Kinase 3 beta , NF-kappa B , Pyridones , Receptors, Cytoplasmic and Nuclear , Tumor Necrosis Factor-alpha , Wnt Signaling Pathway , Animals , Pyridones/pharmacology , NF-kappa B/metabolism , Wnt Signaling Pathway/drug effects , Male , 1-Naphthylisothiocyanate/toxicity , Mice , Receptors, Cytoplasmic and Nuclear/metabolism , Tumor Necrosis Factor-alpha/metabolism , Cholestasis/chemically induced , Cholestasis/metabolism , Cholestasis/drug therapy , Cholestasis/pathology , Glycogen Synthase Kinase 3 beta/metabolism , Chemical and Drug Induced Liver Injury/drug therapy , Chemical and Drug Induced Liver Injury/metabolism , Chemical and Drug Induced Liver Injury/pathology , Chemical and Drug Induced Liver Injury/prevention & control , Mice, Inbred C57BL , beta Catenin/metabolism , Liver/drug effects , Liver/metabolism , Liver/pathologyABSTRACT
A bidirectional relationship exists between atrial fibrillation (AF) and kidney function. Uncontrolled AF may lead to kidney injury, whereas renal dysfunction may contribute to AF initiation and maintenance. This study aimed to investigate the protective effect of the sodium glucose cotransporter-2 inhibitor empagliflozin (EMPA) on acute kidney injury (AKI) associated with AF induced by acetylcholine and calcium chloride (ACh/CaCl2) in rats and elucidate the potential underlying mechanism. Rats were randomly divided as follows: control (CTRL) group: administered vehicles only; AF group: intravenously injected 1â¯ml/kg of an ACh/CaCl2 mixture for seven days to induce AF; EMPA group: orally administered EMPA (30â¯mg/kg) for seven days; AF+EMPA10 and AF+EMPA30 groups: co-administered the induction mixture and EMPA (10 and 30â¯mg/kg, respectively) for seven days. Our results showed that EMPA (10 and 30â¯mg/kg) effectively maintained kidney function and demonstrated a significant antioxidant potential. EMPA also suppressed AF-induced renal tubulointerstitial injury and fibrotic changes concurrently with reducing renal levels of the pro-inflammatory cytokines tumour necrosis factor-α (TNF-α) and interleukin-6, as well as the pro-fibrotic marker transforming growth factor beta-1 and collagen type I. Mechanistically, EMPA boosted nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) renal tissue expression while repressing nuclear factor kappa B (NF-κB) activation. In addition, these beneficial effects of EMPA on kidneys were concurrent with its ability to effectively inhibit AF-related electrocardiographic changes, reduce incidence and duration of AF episodes, and markedly suppress serum B-type natriuretic peptide and C-reactive protein levels. In conclusion, EMPA protected against AKI associated with AF induced by ACh/CaCl2 in rats through simultaneous modulation of the Nrf2/HO-1 and the NF-κB/TNF-α signaling pathways, exerting antioxidant, anti-inflammatory, and anti-fibrotic effects.
Subject(s)
Acute Kidney Injury , Atrial Fibrillation , Benzhydryl Compounds , Glucosides , NF-E2-Related Factor 2 , NF-kappa B , Signal Transduction , Sodium-Glucose Transporter 2 Inhibitors , Tumor Necrosis Factor-alpha , Animals , Glucosides/pharmacology , Glucosides/therapeutic use , NF-E2-Related Factor 2/metabolism , Acute Kidney Injury/prevention & control , Acute Kidney Injury/metabolism , Acute Kidney Injury/etiology , NF-kappa B/metabolism , Benzhydryl Compounds/pharmacology , Male , Signal Transduction/drug effects , Tumor Necrosis Factor-alpha/metabolism , Atrial Fibrillation/prevention & control , Atrial Fibrillation/drug therapy , Atrial Fibrillation/etiology , Sodium-Glucose Transporter 2 Inhibitors/pharmacology , Rats , Rats, Sprague-Dawley , Heme Oxygenase (Decyclizing)/metabolism , Kidney/drug effects , Kidney/metabolism , Kidney/pathologyABSTRACT
Intrahepatic cholestasis is a common clinical form of hepatobiliary injury characterized by the intrahepatic accumulation of toxic bile acids. Besides its antidiabetic activity, the dipeptidyl peptidase IV inhibitor sitagliptin (SG) has been recently assigned diverse pharmacological activities and therapeutic potential against different disorders owing to its emerging antioxidant and anti-inflammatory properties. The current study explored the potential hepatoprotective effect of SG on α-naphthyl isothiocyanate (ANIT)-induced cholestatic liver injury (CLI) in mice and investigate its possible targeted signaling pathways. Mice received SG (10 and 20â¯mg/kg) for four consecutive days, two days before and after a single oral administration of ANIT (75â¯mg/kg). Our results revealed that SG administration remarkably prevented ANIT-induced histopathological lesions in the liver and maintained hepatic functions and oxidative/antioxidant balance. Ultimately, SG counteracted the inflammatory response in the liver, as indicated by the marked suppression of hepatic expression of NF-κB, TNF-α, and IL-6. Moreover, it inhibited the endoplasmic reticulum (ER) stress response in the liver. These beneï¬cial effects of SG were accompanied by upregulation of SIRT1, p-AMPK, and Nrf2 expressions while downregulating keap1 expression in the liver. In conclusion, this study is the first to demonstrate the ability of SG to protect against ANIT-induced CLI through modulating multiple signaling cascades, including SIRT1/AMPK, Nrf2/keap1, and NF-кB, which resulted in enhanced antioxidant capacity and repressed inflammatory and ER stress responses in the liver.
ABSTRACT
Diclofenac (DF)-induced acute kidney injury (AKI) is characterized by glomerular dysfunction and acute tubular necrosis. Due to limited treatment approaches, effective and safe drug therapy to protect against such AKI is still needed. Diacetylrhein (DAR), an anthraquinone derivative, has different antioxidant and anti-inflammatory properties. Therefore, the aim of the current study was to investigate the renoprotective effect of DAR on DF-induced AKI while elucidating the potential underlying mechanism. Our results showed that DAR (50 and 100 mg/kg) markedly abrogated DF-induced kidney dysfunction decreasing SCr, BUN, serum NGAL, and serum KIM1 levels. Moreover, DAR treatment remarkably maintained renal redox balance and reduced the levels of pro-inflammatory biomarkers in the kidney. Mechanistically, DAR boosted Nrf2/HO-1 antioxidant and anti-inflammatory response in the kidney while suppressing renal TLR4/NF-κB and NLRP3/caspase-1 inflammatory signaling pathways. In addition, DAR markedly inhibited renal pyroptosis via targeting of GSDMD activation. Collectively, this study confirmed that the interplay between Nrf2/HO-1 and TLR4/NF-κB/NLRP3/Caspase-1 signaling pathways and pyroptotic cell death mediates DF-induced AKI and reported that DAR has a dose-dependent renoprotective effect on DF-induced AKI in rats. This effect is due to powerful antioxidant, anti-inflammatory, and anti-pyroptotic activities that could provide a promising treatment approach to protect against DF-induced AKI.
Subject(s)
Acute Kidney Injury , NF-kappa B , Rats , Animals , NF-kappa B/metabolism , Diclofenac/toxicity , NF-E2-Related Factor 2/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Antioxidants/metabolism , Toll-Like Receptor 4/metabolism , Signal Transduction , Acute Kidney Injury/chemically induced , Acute Kidney Injury/prevention & control , Acute Kidney Injury/drug therapy , Kidney , Anti-Inflammatory Agents/therapeutic use , Caspases/metabolismABSTRACT
The aim of this study is to explore the potential of repurposing the antiarthritic drug diacerein (DCN) against diclofenac (DCF)-induced acute nephrotoxicity in rats. Rats were divided into four groups: Group I (CTRL) served as the negative control; Group II (DCF) served as the positive control and was injected with DCF (50 mg/kg/day) for three consecutive days (fourth-sixth) while being deprived of water starting on day 5; Group III (DCF + DCN50) and Group IV (DCF + DCN100) were orally administered DCN (50 and 100 mg/kg/day, respectively) for six days and injected with DCF, while being deprived of water as described above. Changes in kidney function biomarkers were assessed. Levels of MDA and GSH along with NO content in kidney tissues were measured as indicators of oxidative stress status. Histopathological changes of the renal cortex and medulla were evaluated. Changes in renal NF-κB and SIRT-1 levels were immunohistochemically addressed. Western blotting was used to estimate the relative expressions of HIF-1α, p53, and active caspase-3. Our results showed that DCN inhibited kidney dysfunction and suppressed oxidative stress, which were reflected in improved kidney architecture, including less tubular degeneration and necrosis in the cortex and medulla. Interestingly, DCN reduced renal HIF-1α, p53, and active caspase-3 expression and NF-κB activation while increasing renal SIRT1 expression. In conclusion, for the first time, DCN counteracts acute kidney injury induced by DCF in rats by its anti-oxidative, anti-inflammatory, antinecrotic, and anti-apoptotic effects in a dose-dependent manner, which are mainly via targeting SIRT1/HIF-1α/NF-κB and SIRT1/p53 regulatory axes.
Subject(s)
Diclofenac , NF-kappa B , Rats , Animals , NF-kappa B/metabolism , Diclofenac/therapeutic use , Caspase 3/metabolism , Tumor Suppressor Protein p53/metabolism , Sirtuin 1/metabolism , Apoptosis , Kidney , Oxidative Stress , Water/metabolism , Water/pharmacologyABSTRACT
Fulminant hepatic failure (FHF) is the terminal phase of acute liver injury, which is characterized by massive hepatocyte necrosis and rapid hepatic dysfunction in patients without preexisting liver disease. There are currently no therapeutic options for such a life-threatening hepatic failure except liver transplantation; therefore, the terminal phase of the underlying acute liver injury should be avoided. Tomatidine (TOM), asteroidal alkaloid, may have different biological activities, including antioxidant and anti-inflammatory effects. Herein, the lipopolysaccharide (LPS)/D-galactosamine (D-GalN)-induced FHF mouse model was established to explore the protective potential of TOM and the underlying mechanisms of action. TOM pretreatment significantly inhibited hepatocyte necrosis and decreased serum aminotransferase activities in LPS/D-GalN-stimulated mice. TOM further increased the level of different antioxidant enzymes while reducing lipid peroxidation biomarkers in the liver. These beneficial effects of TOM were shown to be associated with targeting of NF-κB signaling pathways, where TOM repressed NF-κB activation and decreased LPS/D-GalN-induced TNF-α, IL-6, IL-1ß, and iNOS production. Moreover, TOM prevented LPS/D-GalN-induced upregulation of Keap1 expression and downregulation of Nrf2 and HO-1 expression, leading to increased Nrf2-binding activity and HO-1 levels. Besides, TOM pretreatment repressed LPS/D-GalN-induced upregulation of proliferating cell nuclear antigen (PCNA) expression, which spared the hepatocytes from damage and subsequent repair following the LPS/D-GalN challenge. Collectively, our findings revealed that TOM has a protective effect on LPS/D-GalN-induced FHF in mice, showing powerful antioxidant and anti-inflammatory effects, primarily mediated via modulating Keap1/Nrf2/HO-1 and NF-κB/TNF-α/IL-6/IL-1ß/iNOS signaling pathways.
Subject(s)
Liver Failure, Acute , NF-kappa B , Tomatine/analogs & derivatives , Humans , Mice , Animals , NF-kappa B/metabolism , Antioxidants/pharmacology , Liver Failure, Acute/chemically induced , Liver Failure, Acute/drug therapy , Liver Failure, Acute/metabolism , NF-E2-Related Factor 2/metabolism , Lipopolysaccharides/pharmacology , Tumor Necrosis Factor-alpha/metabolism , Interleukin-6/metabolism , Kelch-Like ECH-Associated Protein 1/metabolism , Signal Transduction , Liver , Oxidative Stress , Inflammation/drug therapy , Inflammation/metabolism , Anti-Inflammatory Agents/pharmacology , Necrosis/metabolism , Galactosamine/pharmacologyABSTRACT
A novel series of 12 antipyrine derivatives containing 1,3,4-oxadiazoles (4a-d), 1,3,4-thiadiazoles (6a-d), and pyrimidines (8a-d), was preparedand assessed for its potential in vitro COX-2 inhibitors. Compared to Celecoxib, compounds 4b-d and 8d were the most potent derivatives c with a half-maximal inhibitory concentration range of 53-69 nM. Considering COX-2 selectivity index, compounds 4 b and 4c were chosen among these most potent derivatives for further investigation. The in vivo ability of compounds 4 b and 4c to counteract carrageenan-induced paw edoema has been assessed and their potential underlying mechanisms have been elucidated and the results have been further validated using molecular docking simulations.
Subject(s)
Anti-Inflammatory Agents , Antipyrine , Humans , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Antipyrine/pharmacology , Celecoxib/pharmacology , Cyclooxygenase 2/metabolism , Cyclooxygenase 2 Inhibitors/pharmacology , Drug Design , Edema/drug therapy , Molecular Docking Simulation , Structure-Activity RelationshipABSTRACT
PURPOSE: Mitochondrial dysfunction is central to breaking the barrier integrity of retinal endothelial cells (RECs) in various blinding eye diseases such as diabetic retinopathy and retinopathy of prematurity. Therefore, we aimed to investigate the role of different mitochondrial constituents, specifically those of oxidative phosphorylation (OxPhos), in maintaining the barrier function of RECs. METHODS: Electric cell-substrate impedance sensing (ECIS) technology was used to assess in real time the role of different mitochondrial components in the total impedance (Z) of human RECs (HRECs) and its components: capacitance (C) and the total resistance (R). HRECs were treated with specific mitochondrial inhibitors that target different steps in OxPhos: rotenone for complex I, oligomycin for complex V (ATP synthase), and FCCP for uncoupling OxPhos. Furthermore, data were modeled to investigate the effects of these inhibitors on the three parameters that govern the total resistance of cells: Cell-cell interactions (Rb), cell-matrix interactions (α), and cell membrane permeability (Cm). RESULTS: Rotenone (1 µM) produced the greatest reduction in Z, followed by FCCP (1 µM), whereas no reduction in Z was observed after oligomycin (1 µM) treatment. We then further deconvoluted the effects of these inhibitors on the Rb, α, and Cm parameters. Rotenone (1 µM) completely abolished the resistance contribution of Rb, as the Rb became zero immediately after the treatment. Secondly, FCCP (1 µM) eliminated the resistance contribution of Rb only after 2.5 h and increased Cm without a significant effect on α. Lastly, of all the inhibitors used, oligomycin had the lowest impact on Rb, as evidenced by the fact that this value became similar to that of the control group at the end of the experiment without noticeable effects on Cm or α. CONCLUSION: Our study demonstrates the differential roles of complex I, complex V, and OxPhos coupling in maintaining the barrier functionality of HRECs. We specifically showed that complex I is the most important component in regulating HREC barrier integrity. These observed differences are significant since they could serve as the basis for future pharmacological and gene expression studies aiming to improve the activity of complex I and thereby provide avenues for therapeutic modalities in endothelial-associated retinal diseases.
Subject(s)
Diabetic Retinopathy , Oxidative Phosphorylation , Infant, Newborn , Humans , Rotenone/pharmacology , Endothelial Cells/metabolism , Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone/metabolism , Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone/pharmacology , Mitochondria/metabolism , Diabetic Retinopathy/metabolism , Oligomycins/pharmacologyABSTRACT
The current study aims to investigate the possible protective effect of escin, the active constituent of a natural mixture of triterpene saponin glycoside, against immune-mediated hepatitis driven by concanavalin A (Con A) and to elucidate its possible underlying mechanisms. Adult male mice were administered Con A (15 mg/kg, intravenously) for 8 h. In the treated groups, mice were pretreated with escin daily (10 mg/kg in CMC, orally) for 4 days before Con A intoxication. In addition, escin was administered in a group to examine its effect on normal mice. Our results showed that escin inhibited Con A-induced elevation in liver enzymes (ALT, AST, and LDH) and curbed the Con A-induced hepatocyte necrosis and apoptosis together with abrogating the death pathway, JNK. Coincidentally, escin has shown a reduction in neutrophil, CD4+ T cell, and monocyte infiltration into the liver. In addition, escin modulated the cellular oxidant status by compensating for the Con A-depleted expression of the transcription factor Nrf2 and the stress protein hemeoxygenase-1. These effects were in good agreement with the restraining effect of escin on Con A-instigated overexpression of NF-κB and the pro-inflammatory cytokines TNF-α and IL-17A. Interestingly, Con A provoked the cellular protective pathway IL-22/STAT3, which was revoked by the escin pretreatment. In conclusion, escin shows extended antioxidant, anti-inflammatory, antinecrotic, and anti-apoptotic effects against Con A-induced immune-mediated hepatitis. These effects may collectively be via suppressing immune cell infiltration into the liver and selective modulation of Nrf2/HO-1, TNF-α/NF-κB, TNF-α/JNK, and IL-22/STAT3 signaling pathways.
Subject(s)
Escin , Hepatitis, Autoimmune , Animals , Male , Mice , Concanavalin A , Cytokines/metabolism , Escin/pharmacology , Hepatitis, Autoimmune/drug therapy , Liver , NF-E2-Related Factor 2/metabolism , NF-kappa B/metabolism , Signal Transduction , Tumor Necrosis Factor-alpha/metabolism , Interleukin-22ABSTRACT
The current study aims at repurposing the anti-arthritic drug diacerein (DCN) for the treatment of acetaminophen hepatotoxicity and investigating the potential underlying mechanisms. Mice were randomly divided into six groups receiving either no treatment (control group), 20 mg/kg DCN i.p, 400 mg/kg acetaminophen i.p, DCN 4 h before acetaminophen, DCN 2 h after acetaminophen, or 400 mg/kg N-acetylcysteine (NAC) i.p, 2 h after acetaminophen. Biomarkers of liver dysfunction, oxidative stress, and apoptosis were assessed. Hepatic necroinflammatory changes were evaluated along with hepatic expression of NF-κB and caspase-1. The levels of NLRP3, IL-1ß, IL-4, MCP-1, and TNF-α in the liver, as well as CYP2E1 mRNA expression, were measured. Diacerein significantly reduced biomarkers of liver dysfunction, oxidative stress, hepatocyte necrosis, and infiltration of neutrophils and macrophages whether administered 4 h before or 2 h after acetaminophen. Further, the effects were comparable to those of NAC. Diacerein also counteracted acetaminophen-induced hepatocellular apoptosis by increasing Bcl-2 and decreasing Bax and caspase-3 expression levels. Moreover, DCN normalized hepatic TNF-α and significantly decreased NF-κB p65 expression. Accordingly, DCN can prevent or reverse acetaminophen hepatotoxicity in mice, suggesting potential utility as a repurposed drug for clinical treatment.
Subject(s)
Acetaminophen , Chemical and Drug Induced Liver Injury , Acetaminophen/metabolism , Acetaminophen/toxicity , Animals , Anthraquinones , Caspase 1/metabolism , Chemical and Drug Induced Liver Injury/metabolism , Chemical and Drug Induced Liver Injury/prevention & control , Interleukin-4/metabolism , Liver/metabolism , Mice , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Oxidative Stress , Signal TransductionABSTRACT
BACKGROUND: Ulcerative colitis (UC) is a chronic colon inflammation that is linked to exposure to environmental factors leading to improper immune responses to enteric microbes in genetically susceptible individuals. This study was designed to explore the possible protective impact of Empagliflozin (EMPA), an anti-diabetic sodium-glucose cotransporter-2 (SGLT2) inhibitor, on acetic acid (AA)-induced UC in rats. METHOD: Intrarectal instillation of AA (2 ml, 3% v/v) was used to induce UC. EMPA (10 & 30 mg/kg) was administered orally for 11 days. RESULTS: EMPA successfully counteracted AA-induced UC that was manifested by improving colonic histopathological architecture concomitant with a marked decrease in disease activity index (DAI), colon weight, weight/length ratio, serum lactate dehydrogenase (LDH) activity, and C-reactive protein (CRP) level. Additionally, EMPA successfully restored the disrupted oxidant/antioxidants balance induced by AA. Moreover, EMPA significantly induced silent information regulator-1(SIRT-1) expression along with a significant reduction in phosphatidylinositol-3-Kinase (PI3K), Protein Kinase B (AKT), nuclear factor kappa B (NF-κB), tumor necrosis factor (TNF)-α and interleukins (IL-1ß and IL-6) expression in colonic tissues. Furthermore, EMPA successfully improved the colonic barrier that was appeared from the marked induction of tight junction proteins level (occludin and claudin-1). CONCLUSION: EMPA successfully counteracted AA-induced UC in rats via the modulation of SIRT1/PI3K/AKT/NF-κB inflammatory pathway, normalizing oxidant/antioxidants balance, and improving the integrity of colon barrier.
Subject(s)
Colitis, Ulcerative , Sirtuins , Acetic Acid , Animals , Benzhydryl Compounds , Colitis, Ulcerative/chemically induced , Colitis, Ulcerative/drug therapy , Colitis, Ulcerative/prevention & control , Colon/metabolism , Dextran Sulfate/adverse effects , Dextran Sulfate/metabolism , Disease Models, Animal , Glucosides , NF-kappa B/metabolism , Phosphatidylinositol 3-Kinase/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Rats , Sirtuins/metabolismABSTRACT
AIMS: The current study aims to investigate the role of the key effector cytokines produced by CD4+T cells in the pathogenesis of Con A-induced liver injury in mice and testing whether etanercept can be repurposed to differentially regulate these cytokines. MAIN METHODS: Four groups of mice were used: group I: control group, group II: mice received 15 mg/kg Con A i.v, group III: mice received 15 mg/kg etanercept i.p, group IV: mice received both Con A and etanercept as described. Hepatic injury and necroinflammation were assessed. Infiltration of CD4+ T cells and neutrophils were evaluated. Hepatic levels of TNF-α, IL-4, IL-10, and MDA were assigned and expression of NF-κB as well. KEY FINDINGS: A significant decrease in ALT, AST, and LDH levels occurred when etanercept was injected before Con A. Hepatic necrosis and infiltration of CD4+ T cells and neutrophils were reduced by etanercept. Levels of TNF-α, IL-4, and MDA were significantly decreased in group IV compared to group II while that of IL-10 was increased. Also, number of NF-κB positive cells was significantly low in group IV. SIGNIFICANCE: The study elucidates an interplay between the two effector cytokines of CD4+ T cells, TNF-α and IL-4, and their key role in Con A-induced liver injury. Additionally, our results showed that etanercept could be repurposed to differentially regulate effector cytokines produced by CD4+ T cells. Not only TNF-α, but also IL-4 signaling pathways, through which it exerts immunomodulatory, anti-inflammatory, and anti-oxidant effects leading to attenuation of Con A-induced liver injury.
Subject(s)
CD4-Positive T-Lymphocytes/immunology , Chemical and Drug Induced Liver Injury/drug therapy , Concanavalin A/toxicity , Cytokines/metabolism , Etanercept/pharmacology , Hepatitis/drug therapy , Immunosuppressive Agents/pharmacology , Animals , Anti-Inflammatory Agents/pharmacology , Chemical and Drug Induced Liver Injury/etiology , Chemical and Drug Induced Liver Injury/pathology , Hepatitis/etiology , Hepatitis/pathology , Male , Mice , Mice, Inbred BALB C , Mitogens/toxicity , Signal TransductionABSTRACT
AIMS: Immune mediated liver injury includes activation of different immune pathways that requires various modalities to control their consequences. The current study involves evaluation of retinoic acid (RA) modulatory effects on immune responses induced in concanavalin A (ConA) model of acute hepatitis. MAIN METHODS: Mice were divided as follows: Control group; RA group: received 35â¯mg/kg RA; ConA group: received 15â¯mg/kg ConA; ConAâ¯+â¯RA group: received ConA and RA as described. Liver function biomarkers were measured in addition to malondialdehyde as lipid peroxidation biomarker. Liver tissue sections were scored for necro-inflammation, neutrophils infiltration, CD4+ T cells infiltration and NF-κb positive cells. Effect on hepatic levels of TNF-α, IL-4, IL-10 and MCP-1 was evaluated as well. KEY FINDINGS: Injection of RA before ConA significantly (pâ¯<â¯0.001) decreased ALT, AST and LDH levels compared to their levels in ConA group. Hepatic infiltration of neutrophils and CD4+ T cells was markedly (pâ¯<â¯0.001) reduced by RA. Hepatic injury, necrosis and expression of NF-κb were significantly decreased by RA when injected before ConA challenge. A significant decrease in the measured cytokines TNF-α and IL-4 was observed in ConAâ¯+â¯RA group in addition to a decrease in MCP-1 level. On the other hand, IL-10 was significantly increased in the latter group compared to ConA group. SIGNIFICANCE: RA can protect against ConA-induced hepatitis through: interrupting early inflammatory response as neutrophils, monocytes and CD4+ T cells infiltration, modulating IL-4 level and subsequent production of TNF-α and NF-κb activation, mitigating second inflammatory responses through increasing IL-10 liver production.
Subject(s)
Anti-Inflammatory Agents/pharmacology , CD4-Positive T-Lymphocytes/drug effects , Chemical and Drug Induced Liver Injury/immunology , Cytokines/immunology , Hepatitis/immunology , Tretinoin/pharmacology , Animals , CD4-Positive T-Lymphocytes/immunology , Chemical and Drug Induced Liver Injury/pathology , Concanavalin A , Hepatitis/pathology , Liver/drug effects , Liver/immunology , Liver/pathology , Male , Mice, Inbred BALB C , NF-kappa B/immunology , Neutrophils/drug effects , Neutrophils/immunology , Signal Transduction/drug effectsABSTRACT
Tyrosine kinase inhibitors have been emerged recently as an effective therapy against liver fibrosis. The current study was designed to test a potential anti-fibrotic effect of the multi-targeted receptor tyrosine kinase inhibitor pazopanib. Carbon tetrachloride (CCl4; 1 mL/kg) was injected intraperitoneally (i.p.) twice/week for 8 weeks. Pazopanib (10 and 30 mg/kg, i.p.) was administered three times/week at the beginning of week 5. Levels of liver function biomarkers (alanine aminotransferase (ALT), aspartate aminotransferase (AST), albumin, and total bilirubin), malondialdehyde, transforming growth factor-ß1 (TGF-ß1), caspase-3, factor-related apoptosis (FAS), vascular endothelial growth factor (VEGF) receptor-1, and pigment endothelial derived factor (PEDF) were measured. The tissue level of the inflammatory cytokines IL-6 and tumor necrosis factor-α (TNF-α) were assigned. Fibrotic area was measured by morphometry and expression of alpha-smooth muscle actin (α-SMA), caspase-3, platelet-derived growth factor (PDGF) receptor-ß, and matrix metalloproteinase-2 (MMP-2) was scored immunohistochemically. Hepatic expression of collagen-1-alpha-1 (Col1A1) and tissue inhibitor metalloproteinase-1 (TIMP-1) mRNA were assigned by RT-qPCR. Injection of CCl4 resulted in marked collagen deposition, necroinflammation, and fibrosis (2.67%). Pazopanib in a dose of 30 mg/kg improved liver function, reduced fibrosis (1.48%), and decreased significantly (P < 0.01) liver expression of malondialdehyde, TGF-ß1, IL-6, TNF-α, Col1A1, TIMP-1, α-SMA, MMP-2, PDGF receptor-ß, and VEGF receptor-1. Additionally, the apoptotic markers (caspase-3, FAS) and the anti-angiogenic factor PEDF were upregulated significantly (P < 0.05). Pazopanib at a certain dose level can halt liver fibrosis progression through modulating inflammatory cytokines, suppressing stellate cell activity, inducing apoptosis, and potentially regulating angiogenesis.