Oxidative stress-related molecules and liver fibrosis

Antifibrotic Effect of Smad Decoy Oligodeoxynucleotide in a CCl₄-Induced Hepatic Fibrosis Animal Model

Hepatic fibrosis is the wound-healing process of chronic hepatic disease that leads to the end-stage of hepatocellular carcinoma and demolition of hepatic structures. Epithelial–mesenchymal transition (EMT) has been identified to phenotypic conversion of the epithelium to mesenchymal phenotype that occurred during fibrosis. Smad decoy oligodeoxynucleotide (ODN) is a synthetic DNA fragment containing a complementary sequence of Smad transcription factor. Thus, this study evaluated the antifibrotic effects of Smad decoy ODN on carbon tetrachloride (CCl₄)-induced hepatic fibrosis in mice. As shown in histological results, CCl₄ treatment triggered hepatic fibrosis and increased Smad expression. On the contrary, Smad decoy ODN administration suppressed fibrogenesis and EMT process. The expression of Smad signaling and EMT-associated protein was markedly decreased in Smad decoy ODN-treated mice compared with CCl₄-injured mice. In conclusion, these data indicate the practicability of Smad decoy ODN administration for preventing hepatic fibrosis and EMT processes.

Growth Factors, Oxidative Damage, and Inflammation in Exfoliation Syndrome

Exfoliation syndrome (XFS) produces deleterious ocular aging and has protean systemic manifestations. Local ocular production of TGFβ1 is of central importance in XFS. TGFβ1 appears to induce the expression of LOXL1 and the production of other extracellular matrix components which are known to be present in exfoliation material. Furthermore, results from several studies find that the aqueous humor of exfoliation glaucoma patients exhibits a decreased antioxidant defense and increased oxidative stress systems. Finally, studies show that the levels of interleukin-6 and interleukin-8 in the aqueous humor of XFS patients were 3-fold higher than in controls. Overall TGFβ1, as well as a prooxidative and proinflammatory environment seems to play an important role in XFS.

Pomegranate action in curbing the incidence of liver injury triggered by Diethylnitrosamine by declining oxidative stress via Nrf2 and NFκB regulation

Unearthing and employment of healthy substitutes is now in demand to tackle a number of diseases due to the excessive repercussions of synthetic drugs. In this frame of reference pomegranate juice (PGJ) is a boon comprising of anthocyanins and hydrolysable tannins, known for its anti-oxidant and anti-inflammatory properties. Despite various documented roles of PGJ, there are no studies on antifibrotic potential in NDEA-induced mammalian liver fibrotic model. Hepatic fibrosis in rats was induced by the intra-peritoneal injection of NDEA (10 mlkg-1b.wt. of 1% NDEA) in two weeks. Biochemical, histopathological and ultra-structural studies were carried out on control, fibrotic and treated rats. The liver function indices and LPO were increased significantly by intoxication of NDEA. The antioxidant status was disturbed with the decrease in SOD, GST and catalase in the liver and membrane-ATPases as well. Histopathological observations by H&E, M&T, picro-sirius and ultra-structural scrutiny by SEM and TEM indicated liver damage and increase in COX2 and α-SMA by NDEA which was successfully rectified by the supplementation of PGJ. PGJ abrogates liver fibrosis instigated by NDEA in Wistar rats by declining oxidative stress via regulation of Nrf2 and NFκB. These findings point towards pomegranate as a potential and efficacious therapeutic agent against liver fibrosis.

Oxidative stress is bane in chronic liver diseases: Clinical and experimental perspective

Oxidative stress plays an important role in the pathogenesis of various chronic liver diseases (CLD) and increasing evidence have confirmed the contributory role of oxidative stress in the pathogenesis of drugs and chemical-induced CLD. Chronic liver injury is manifested as necrosis, cholestasis, fibrosis, and cirrhosis. Chronic administration of anti-tubercular, anti-retroviral, immunosuppressive drugs is reported to induce free radical generation during their biotransformation in the liver. Further, these reactive intermediates are said to induce profibrogenic cytokines, several inflammatory markers, collagen synthesis during the progression of hepatic fibrosis. Oxidative stress and free radicals are reported to induce activation and proliferation of hepatic stellate cells in the injured liver leading to the progression of CLD. Hence, to counteract or to scavenge these reactive intermediates, several plant-derived antioxidant principles have been effectively employed against oxidative stress and came out with promising results in human and experimental models of CLD. This review summarizes the relationships between oxidative stress and different liver pathogenesis induced by drugs and xenobiotics, focusing upon different chronic liver injury induced by alcohol, antitubercular drugs and hyperactivity of antiretroviral drugs in HIV patients, viral hepatitis infection induced oxidative stress.

Possible Synergistic Effects of Glutathione and C-Reactive Protein in the Progression of Liver Cirrhosis

Liver cirrhosis is often associated with increased inflammatory responses and changes of glutathione (GSH) status. The possible interactions between these two factors in mediating damages of liver function remain unclear. Here, we measured the inflammatory responses and GSH status in liver cirrhotic patients and compared them with healthy subjects. In addition, we assessed the relationship of the GSH status and levels of inflammatory markers with the severity of the disease. This was a cross-sectional study. In total, we recruited 63 liver cirrhotic patients with Child⁻Turcotte⁻Pugh class A scores, and 12 patients with class B⁻C scores, together with 110 healthy subjects. Patients with class B⁻C scores showed the highest level of high-sensitivity C-reactive protein (hs-CRP) when compared with class A patients or healthy subjects. Patients in class A group had significantly higher GSH levels when compared with class B⁻C group or healthy subjects. After adjusting for potential confounders and each other, serum hs-CRP levels showed positive association with the Child⁻Turcotte⁻Pugh scores, while GSH levels showed negative association with Child⁻Turcotte⁻Pugh scores. Interactions were found between levels of plasma GSH and serum hs-CRP (β = 0.004, p = 0.016). CRP and GSH levels, which had showed interactions, were associated with the severity of liver cirrhosis.

Combination effects of airborne particulate matter exposure and high-fat diet on hepatic fibrosis through regulating the ROS-endoplasmic reticulum stress-TGFβ/SMADs axis in mice

BACKGROUND

Hepatic fibrosis, characterized by an excessive accumulation of extracellular matrix, is associated with toxic substance exposure, chronic infections, mechanical injury, airborne fine particulate matter (PM_2.5) exposure and metabolic disease. This study aimed to investigate the effect and mechanism of long-term, real-world airborne particulate matter (PM) exposure on hepatic fibrosis and further explored whether combination treatment of PM exposure and high-fat diet (HFD) aggravate the adverse effects in mice.

METHODS AND RESULTS

Six-week-old male C57BL/6J mice fed with either a standard chow diet (STD) or an HFD were treated with either filtered air (FA) or PM for 18 weeks. Metabolic parameters, histological examination, gene expression analysis, and Western blot analysis were utilized to measure the effect and mechanism of PM exposure on hepatic fibrosis and to further analyze the synergistic effect of HFD. Subchronic airborne PM exposure induces hepatic fibrosis in mice, and combination treatment of PM exposure and HFD accelerate the adverse effect. Meanwhile, subchronic exposure to real-world PM increased the level of hepatic ROS, and the expression of endoplasmic reticulum (ER) stress markers (GRP78 and CHOP), p-SMAD2 and p-SMAD3, as well as up-regulated TGFβ and collagen 1 in liver tissues. Furthermore, PM exposure and HFD displayed the synergistic effects on these changes in liver.

CONCLUSION

Our findings indicate that airborne PM exposure aggravates HFD -induced hepatic fibrosis. The ROS-ER stress-TGFβ/SMADs regulatory axis mediates the effects of airborne PM exposure on accelerating hepatic fibrosis.

Hepaprotective Effect of Standardized Ecklonia stolonifera Formulation on CCl4-Induced Liver Injury in Sprague-Dawley Rats

The liver is an essential organ for the detoxification of exogenous xenobiotics, drugs and toxic substances. The incidence rate of non-alcoholic liver injury increases due to dietary habit change and drug use increase. Our previous study demonstrated that Ecklonia stolonifera (ES) formulation has hepatoprotective effect against alcohol-induced liver injury in rat and tacrine-induced hepatotoxicity in HepG2 cells. This present study was designated to elucidate hepatoprotective effects of ES formulation against carbon tetrachloride (CCl₄)-induced liver injury in Sprague Dawley rat. Sixty rats were randomly divided into six groups. The rats were treated orally with ES formulation and silymarin (served as positive control, only 100 mg/kg/day) at a dose of 50, 100, or 200 mg/kg/day for 21 days. Seven days after treatment, liver injury was induced by intraperitoneal injection of CCl₄ (1.5 ml/kg, twice a week for 14 days). The administration of CCl₄ exhibited significant elevation of hepatic enzymes (like AST and ALT), and decrease of antioxidant related enzymes (superoxide dismutase, glutathione peroxidase and catalase) and glutathione. Then, it leaded to DNA damages (8-oxo-2′-deoxyguanosine) and lipid peroxidation (malondialdehyde). Administration of ES formulation inhibited imbalance of above factors compared to CCl₄ induced rat in a dose dependent manner. Real time PCR analysis indicates that CYP2E1 was upregulated in CCl₄ induced rat. However, increased gene expression was compromised by ES formulation treatment. These findings suggests that ES formulation could protect hepatotoxicity caused by CCl₄ via two pathways: elevation of antioxidant enzymes and normalization of CYP2E1 enzyme.

Anti-oxidative and anti-inflammatory effects of Rosa Mosqueta oil supplementation in rat liver ischemia-reperfusion

Ischemia-reperfusion (IR) is a deleterious condition associated with liver transplantation or resection that involves pro-oxidant and pro-inflammatory mechanisms.

Biogenic selenium and its hepatoprotective activity

Elemental selenium nanoparticles (SeNPs) have multiple biological activities. In this study, we investigated the protective effects of biogenic SeNPs (BioSeNPs) on CCl₄-induced liver damage in mice. The results showed that: (i) when compared to sodium selenite (SS), BioSeNPs has a similar tissue distribution after intragastrical administration to mice; (ii) BioSeNPs and SS showed comparable efficacy in increasing the activities of glutathione peroxidase and thioredoxin reductase in liver cell lines, mice blood and liver; (iii) pretreatment with BioSeNPs inhibiting the elevation of activities of various enzymes significantly which included aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, lactate dehydrogenase and liver lipid peroxide (p < 0.05 or p < 0.01) in CCl₄-treated mice; (iv) activities of antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase) were significantly increased (p < 0.05 or p < 0.01) after a pretreatment with BioSeNPs in CCl₄-treated mice; (v) histopathological damages in the liver from CCl₄-treated mice were ameliorated by a pretreatment with BioSeNPs. In conclusion, these results have shown that BioSeNPs is able to protect the liver from CCl₄-induced hepatic damage via increasing the antioxidant capacity and inhibiting oxidative damage. BioSeNPs may have the potential to be used as a trace element food supplement inducing antioxidant bioactivities.

SIRT3 protects hepatocytes from oxidative injury by enhancing ROS scavenging and mitochondrial integrity

Evidences of oxidative stress and mitochondrial dysfunction have been recognized in most of clinical and experimental liver diseases. SIRT3, a member of NAD⁺-dependent deacetylases, is mainly localized in mitochondria. So far, the role of SIRT3 in protecting hepatocytes against oxidative stress remains elusive. Herein, we found SIRT3 protein expression is decreased in tert-butyl hydroperoxide (t-BHP)-treated AML12 cells in vitro and primary hepatocytes from CCl₄-injured mice in vivo. To further verify the role of SIRT3 in protecting hepatocytes from t-BHP-induced injury, SIRT3 overexpressed AML12 cell line and primary hepatocytes were generated. SIRT3 overexpressed hepatocytes showed improved cell viability upon t-BHP challenge, with less intracellular reactive oxygen species (ROS) accumulation. SIRT3 overexpression reduced superoxide dismutase 2 acetylation level and stimulated nuclear factor erythroid 2-related factor 2 nuclear translocation to enhance anti-oxidative capacity. Moreover, SIRT3 deacetylated peroxisome proliferator-activated receptor γ coactivator 1α to promote mitochondrial biogenesis, and 8-oxoguanine DNA glycosylase 1 to orchestrate DNA repair, resulting in improved mitochondrial function. Through deacetylating Ku70, SIRT3 also abated mitochondrial translocation of dynamin-related protein 1, to attenuate mitochondrial fragmentation in t-BHP-injured hepatocytes. These results suggested that SIRT3 protected hepatocytes against oxidative stress by enhancing ROS scavenging and maintaining mitochondrial integrity.

The protective effect of vitamin D against carbon tetrachloride damage to the rat liver

We investigated the protective effect of vitamin D against liver damage caused by carbon tetrachloride (CCl₄). Twenty-four male rats were divided into four equal groups: G1, untreated controls; G2, administered CCl₄; G3, administered both CCl₄ and vitamin D for 10 weeks; G4, administered CCl₄ for 10 weeks and vitamin D for 12 weeks. At the end of experiment, intracardiac blood samples were taken and liver samples were removed. Hepatic damage due to CCl₄ was assessed using biochemistry and histopathology. Glutathione (GSH) levels decreased, while malondialdehyde (MDA) levels increased in liver tissues of G2. Alanine transaminase (ALT), alkaline phosphatase (ALP), and gamma-glutamyl-transaminase (GGT) levels increased, while albumin (ALB) levels decreased. Hepatocyte degeneration, lobular disorder, sinusoid dilation, focal necrotic areas, hyperemia, and glycogen loss were observed. Hepatic fibrosis was observed around portal areas and central veins. Bridging fibrous septa were formed between portal veins. By immunohistochemistry, both matrix metalloproteinase-9 (MMP-9) and desmin reactivity were increased. All aspects of liver damage were at least partially prevented in rats treated with vitamin D. Vitamin D appears to act as an antioxidant and anti-fibrotic to protect the rat liver against damage.

Quercetin reverses experimental cirrhosis by immunomodulation of the proinflammatory and profibrotic processes

The ability of quercetin to reverse an established cirrhosis has not yet been investigated. Therefore, the aim of this study was to examine the efficacy of this flavonoid in reversing experimental cirrhosis. Cirrhosis was induced by intraperitoneal administration of TAA (200 mg/kg of body weight) three times per week for 8 weeks or by intraperitoneal petrolatum-CCl₄ (400 mg/kg of body weight) administration three times per week for 8 weeks. To determine the capacity of quercetin to prevent liver fibrosis, the flavonoid (50 mg/kg of body weight, p.o.) was administered daily to rats during the CCl₄ or TAA treatment. To evaluate the ability of quercetin to reverse the previously induced cirrhosis, we first treated rats with CCl₄ for 8 weeks, as previously described and then the flavonoid was administered for four more weeks. We found that the liver anti-inflammatory and antinecrotic effects of quercetin are associated with its antioxidant properties, to the ability of the flavonoid to block NF-κB activation and in consequence to reduce cytokine IL-1. The ability of quercetin to reverse fibrosis may be associated with the capacity of the flavonoid to decrease TGF-β levels, hepatic stellate cell activation, and to promote degradation of the ECM by increasing metalloproteinases. The main conclusion is that quercetin, in addition to its liver protective activity against TAA chronic intoxication, is also capable of reversing a well-stablished cirrhosis by blocking the prooxidant processes and by downregulating the inflammatory and profibrotic responses.

Evaluation of Rumex hastatus leaves against hepatic fibrosis: a rat model

BACKGROUND

Rumex hastatus leaves have been widely used as food additive and for the treatment of various liver ailments. According to our previous studies, ethyle acetate (ERL) and methanolic (MRL) fractions of R. hastatus leaves are an accessible source of natural antioxidants. In the present research work we arranged to investigate the R. hastatus leaves as hepaptoprotective agent verse hepatic damages caused by CCl4.

METHODS

During this project we divided 48 rats into eight groups randomly. CCl4-induced damages were assessed through liver function markers viz.; alkaline phosphatase (ALP), alanine transaminase (ALT), aspartate transaminase (AST), γ-glutamyltransferase (γ-GT) and lactate dehydrogenase (LDH). Changes in lipid profile were checked by measuring serum total cholesterol (TC), triglycerides (Tg), high density lipoproteins (HDL) and low density lipoproteins (LDL). Antioxidant status was checked by the activities of antioxidant enzymes, DNA damages and cellular abnormalities at histo level.

RESULTS

Administration of CCl4 in rats caused significant increase in liver function and lipid profile indicating hepatic damages which were restored by co-administration of R. hastatus extracts. Cellular and DNA damages in hepatic tissues were caused by CCl4 which shown clear hepatic fibrosis in addition to disturb antioxidant enzyme level. Co-treatment with various fractions of R. hastatus leaves regulated these markers of oxidative dysfunctions.

CONCLUSION

From the present report it was inferred that R. hastatus leaves have the ability to reverse CCl4 - induced hepatic damages.

Schisandrin B attenuates CCl4-induced liver fibrosis in rats by regulation of Nrf2-ARE and TGF-β/Smad signaling pathways

Liver fibrosis is a major pathological feature of chronic liver diseases and there is no effective therapy program at present. Schisandrin B (Sch B) is the major bioactive ingredient of Schisandra chinensis, with antioxidative, anti-inflammatory, antitumor, and hepatoprotective properties. This study aimed to investigate the protective effect and related molecular mechanism of Sch B against carbon tetrachloride (CCl₄)-induced liver fibrosis in rats. The in vivo therapeutic effect of Sch B on liver fibrosis induced by CCl₄ was examined in rats. In vitro, rat hepatic stellate cells (HSC-T6) were used to assess the effect of Sch B on the activation of HSCs. Sch B effectively attenuated liver damage and progression of liver fibrosis in rats, as evidenced by improved liver function and decreased collagen deposition. The effects of Sch B were associated with attenuating oxidative stress by activating nuclear factor-erythroid 2-related factor 2 (Nrf2)-mediated antioxidant signaling and suppressing HSC activation by inhibiting the transforming growth factor-β (TGF-β)/Smad signaling pathway. In an in vitro study, it was shown that Sch B inhibited TGF-β-induced HSC activation. Finally, Sch B significantly inhibited TGF-β1-stimulated phosphorylation of Smad and signaling of mitogen-activated protein kinases. This study demonstrates that Sch B prevents the progression of liver fibrosis by the regulation of Nrf2-ARE and TGF-β/Smad signaling pathways, and indicates that Sch B can be used for the treatment of liver fibrosis.

Protective effect and mechanism of ginsenoside Rg1 on carbon tetrachloride‑induced acute liver injury

Liver injury is a common pathological state in various types of liver disease; severe or persistent liver damage is the basis of hepatic failure. Ginsenoside Rg1 (Rg1), one of the primary active ingredients of ginseng, has been reported to reduce concanalin A‑induced hepatitis and protect against lipopolysaccharide‑ and galactosamine‑induced liver injury. However, the underlying protective mechanism of Rg1 in acute liver injury remains unclear. In the present study, a carbon tetrachloride (CCl4)‑induced acute liver injury model was established, and the protective effect of Rg1 on CCl4‑induced acute liver injury was demonstrated in cell culture and animal experimental systems. Further investigation of the mechanisms demonstrated that pretreatment with Rg1 reduced elevated levels of alanine aminotransferase and aspartate aminotransferase, enhanced the antioxidant activity of superoxide dismutase (SOD) and decreased malondialdehyde (MDA) content. Experiments in vitro demonstrated that Rg1 decreased p65 expression and inhibited nuclear factor (NF)‑κB activity. In addition to the effect of Rg1, an NF‑κB inhibitor promoted cell survival, enhanced SOD activity and reduced MDA level. It was observed through in vivo experiments that pretreatment with Rg1 inhibited NF‑κB expression and activity in Kupffer cells and reduced the serum levels of tumor necrosis factor‑α and interleukin‑6. In conclusion, the results of the present study indicated that pretreatment with Rg1 may rescue CCl4‑induced acute liver injury in vivo and in vitro through inhibition of NF‑κB activity, to restore the anti‑oxidative defense system and down‑regulate pro‑inflammatory signaling pathways. The present observations provide a theoretical foundation for the clinical application of Rg1 therapy in acute liver injury.

Modulatory influence of Acacia hydaspica R. Parker ethyl acetate extract against cisplatin inveigled hepatic injury and dyslipidemia in rats

BACKGROUND

Cisplatin (CP) is recommended as a first-line chemotherapeutic agent for solid tumors, however its usage outcomes in severe adverse effects. Acacia hydaspica possesses various phytochemicals and pharmacological activities. The current study aimed to investigate the protective effect of A. hydaspica ethyl acetate extract (AHE) against CP induced aberrations in lipid profile and hepatotoxicity.

METHODS

Rats were randomly separated into six groups (n = 6). Group 1 (control) received distilled water orally for 21 days. Groups 2 (CP control) received a single dose of CP (7.5 mg/kg bw, i.p) on day 16, group 3 (Plant control) received AHE (400 mg/kg b.w, oral) for 21 days, group 4 (post treated group); CP received on day 16 and AHE (400 mg/kg b.w/day, p.o.) was administered after CP till day 21, Group 5 (pretreated group) received AHE (400 mg/kg b.w/day, p.o.) for 21 days and CP (7.5 mg/kg b.w., i.p.) on day 16, group 6 (Silymarin + CP) received 100 mg/kg b.w., p.o. (11 doses/21 days) and CP (7.5 mg/kg b.w., i.p.) on day 16. Lipid profile, liver functional tests, oxidative stress markers, antioxidant enzymes status and histopathological changes were examined.

RESULTS

The present study revealed that CP caused body weights loss and increase liver index. CP significantly increased serum total lipid, triglycerides and LDL-cholesterol levels. Conversely, it significantly decreased serum HDL-cholesterol level. CP induced marked deteriorations in serum liver function biomarkers, reduced antioxidant enzymes in tissue, while elevated tissue oxidative stress markers along with morphological injuries compared to control rats. Treatment with AHE ameliorated CP induced alterations in lipid profile, serum ALT, AST, ALP and total bilirubin levels and liver weight. Furthermore AHE treatment improved the total protein and antioxidant enzymes levels while decreased the level of MDA, H2O2, and NO. The altered parameters were returned to the control level with AHE pretreatment. Histopathological analysis also supported the biochemical findings. Pretreatment seems to be more effective compared to post treatment indicating protective effect.

CONCLUSION

These results reveal that treatment of AHE may be useful in the prevention of CP induced hepatotoxicity due to its antioxidant potential and polyphenolic constituents.

酒精性肝病研究进展

酒精性肝病(alcoholic liver disease, ALD)是一种慢性肝脏疾病, 包括肝脂肪变性、酒精性脂肪性肝炎、肝硬化、肝细胞癌和肝衰竭. 许多因素被认为能促进ALD的发展, 特别是氧化应激, 在酒精代谢期间活性氧物质的产生, 来自内脏脂肪组织的脂肪因子和来自肠道的内毒素等. 目前, ALD的发病机制已被广泛研究, 精确的机制尚待阐明. 在我国随着人类生活水平提高和生活方式的改变, 人群中的嗜酒者的比率逐年上升, 乙醇也已成为导致肝脏损害的第二大原因. 因此, ALD相关治疗也受到人们的广泛关注. 在本文中, 我们就ALD的发病机制、治疗等方面的最新研究进展作一综述.

Euphorbia dracunculoides L. abrogates carbon tetrachloride induced liver and DNA damage in rats

BACKGROUND

Evaluation of Euphorbia dracunculoides of family Euphorbiaceae during previous studies had established the in vitro antioxidant and in vivo anti-inflammatory activities. The plant is used by the local communities of Pakistan for various disorders including rheumatism and edema. In this investigation we have evaluated the hepatoprotective effects against CCl4 induced toxicity in rat.

METHODS

Dry powder of the aerial parts of E. dracunculoides was extracted with 95% methanol to get the extract (EDME). To investigate the hepatoprotective effects of EDME the Sprague-Dawley male rats were divided in to 8 groups with 6 rats in each. Group I and II were the normal and vehicle treated while the Groups III-VI were injected intraperitoneally with 1 ml of CCl4 (30% in olive oil). Rats of Group IV were orally administered with silymarin (50 mg/kg) while the Group V and VI with 200 mg/kg and 400 mg/kg of EDME, respectively. Animals of Group VII (200 mg/kg) and VIII (400 mg/kg) were treated with EDME alone. The treatments were given thrice a week for 4 weeks. Effects of EDME were evaluated for the protective effects against oxidative stress and genotoxicity induced with CCl4 in liver of rat.

RESULTS

Analysis of serum indicated significant (p < 0.05) rise in the level of aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP) and globulin whereas decrease was recorded for the total protein and albumin in CCl4 treated rats. In liver tissues the activity level of catalase (CAT), peroxidase (POD), superoxide dismutase (SOD), glutathione-S-transferase (GST), glutathione (GSH) was decreased while the level of lipid peroxides; thiobarbituric acid reactant substances (TBARS), nitrite and hydrogen peroxide increased in CCl4 treated rats as compared to the control group. Histopathological injuries and DNA damages were recorded in liver of rat with CCl4 treatment. However, co-administration of EDME, dose dependently, ameliorated the CCl4-induced hepatic toxicity in these parameters.

CONCLUSIONS

These results suggested that the phyto-constituents of EDME were able to ameliorate the oxidative stress induced with CCl4 and can be a useful therapeutic agent for oxidative stress related disorders.

Methanol extract of Nymphaea lotus ameliorates carbon tetrachloride-induced chronic liver injury in rats via inhibition of oxidative stress

BACKGROUND

Nymphaea lotus (NL) is an aquatic perennial plant used traditionally in the management of various liver diseases. In this study, the protective effect of methanol extract of NL against carbon tetrachloride (CCl4)-induced chronic hepatotoxicity in rats was investigated.

METHODS

Male Wistar rats were assigned into six groups of five rats each. Group I received corn oil (0.5 mL p.o.) and served as control, group II received CCl4 (1 mL/kg i.p., 1:3 in corn oil), group III received NL (200 mg/kg), and groups IV, V, and VI received CCl4+NL (50, 100, and 200 mg/kg, respectively) for 6 weeks. Twenty-four hours after the last exposure, rats were bled and killed.

RESULTS

The activities of alanine aminotransaminase (ALT), aspartate aminotransferase (AST), and levels of total bilirubin (TB) in the serum, thiobarbituric acid reactive substances (TBARS), superoxide dismutase, catalase, glutathione peroxidase (GPx) and glutathione (GSH) in the liver, and histopathology of the liver were determined using standard procedures. NL significantly (p<0.05) lowered the levels of ALT, AST, and TB and exhibited antioxidant potentials in rats exposed to CCl4 relative to the control values. Specifically, NL at 100 and 200 mg/kg significantly (p<0.05) increased CCl4-induced decrease in hepatic GSH and GPx and also decreased the level of hepatic TBARS in CCl4-intoxicated rats. Histopathological findings revealed cellular infiltration and fibrosis in rats that received CCl4 only, which were ameliorated in rats that received NL+CCl4.

CONCLUSIONS

The data suggest that NL exhibited hepatoprotective effects in CCl4-intoxicated rats via antioxidative mechanism.

Protective Effects of Ethyl Acetate Soluble Fraction of Limonium tetragonum on Diethylnitrosamine-Induced Liver Fibrosis in Rats

Diethylnitrosamine (DEN) is a potent toxic material that can cause necrosis and subsequent fibrosis in the liver. Based on the previously reported hepatoprotective effect of Limonium tetragonum against the proliferation of hepatic stellate cells, we tested the EtOAc soluble fraction of L. tetragonum extract (EALT) in a DEN-induced hepatotoxic rat model. The development of hepatotoxicity including mononuclear cell infiltration and fibrosis induced by intraperitoneal injections of DEN (70 mg/2 mL/kg body weight (b.w.) per week) was observed at 4, 6 and 8 weeks after the first DEN treatment. Administration of EALT (200 mg/kg body weight, per os (p.o.)) induced significant reductions in serum alanine transaminase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), and triglycerides (TG) in DEN-injected rats. Increased oxidative stress in DEN-induced liver fibrosis rats was diminished by EALT treatment through a decrease in malondialdehyde (MDA) and increase in superoxide dismutase (SOD). Histologic findings that included markedly attenuated mononuclear cell infiltration and fibrosis could be observed in liver samples from the EALT-treated groups. An extract of Hovenia dulcis fruit and Sylimarin were used as positive controls. The present study provides direct experimental evidence for EALT attenuated hepatic injury and fibrosis in DEN-treated mice. The L. tetragonum EtOAc fraction might be useful in treating fibrotic liver diseases.

Insights into the Role and Interdependence of Oxidative Stress and Inflammation in Liver Diseases

The crucial roles of oxidative stress and inflammation in the development of hepatic diseases have been unraveled and emphasized for decades. From steatosis to fibrosis, cirrhosis and liver cancer, hepatic oxidative stress, and inflammation are sustained and participated in this pathological progressive process. Notably, increasing evidences showed that oxidative stress and inflammation are tightly related, which are regarded as essential partners that present simultaneously and interact with each other in various pathological conditions, creating a vicious cycle to aggravate the hepatic diseases. Clarifying the interaction of oxidative stress and inflammation is of great importance to provide new directions and targets for developing therapeutic intervention. Herein, this review is concerned with the regulation and interdependence of oxidative stress and inflammation in a variety of liver diseases. In addition to classical mediators and signaling, particular emphasis is placed upon immune suppression, a potential linkage of oxidative stress and inflammation, to provide new inspiration for the treatment of liver diseases. Furthermore, since antioxidation and anti-inflammation have been extensively attempted as the strategies for treatment of liver diseases, the application of herbal medicines and their derived compounds that protect liver from injury via regulating oxidative stress and inflammation collectively were reviewed and discussed.

Ceratonia siliqua pod extract ameliorates Schistosoma mansoni-induced liver fibrosis and oxidative stress

Background

Schistosomiasis is a prevalent parasitic disease found predominantly in tropical and sub-tropical areas of the developing world, with the second highest socioeconomic and public health burden despite strenuous control efforts. In the present study, we aimed to investigate the ameliorative effects of Ceratonia siliqua pod extract (CPE) on liver fibrosis and oxidative stress in mice infected with Schistosoma mansoni.

Methods

The schistosomal hepatopathologic mouse model was established by tail immersion with schistosomal cercaria. The extract was given daily for 10 days beginning 42 days post-infection. Liver samples were obtained from mice sacrificed 9 weeks after infection. Liver histopathological changes were observed with hematoxylin-eosin and Masson trichrome staining.

Results

Typical schistosomal hepatopathologic changes were induced in the untreated mice. However, the oral administration of CPE was effective in reducing worm number and the egg load in the liver. This treatment also decreased granuloma size and collagen deposition by inhibiting tissue inhibitor of metalloproteinases-2 (TIMP-2) expression. Schistosomal infection induced oxidative stress by increasing lipid peroxidation (LPO) and nitrite/nitrate (nitric oxide; NO) production along with concomitant decreases in glutathione (GSH) and various antioxidant enzymes, including superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase. However, treatment of mice with CPE at 300 or 600 mg/kg inhibited LPO and NO production, increased GSH content, and restored the activities of the antioxidant enzymes compared with untreated infected mice. Furthermore, treatment with CPE inhibited apoptosis, as indicated by the reduced Bax expression in hepatic tissue.

Conclusion

These data indicated that extracts from Ceratonia siliqua pods may play an important role in combating schistosomal hepatopathology and may inhibit granuloma formation and liver fibrosis through down-regulation of TIMP-2 expression.

Electronic supplementary material

The online version of this article (doi:10.1186/s12906-016-1389-1) contains supplementary material, which is available to authorized users.

Forskolin, a hedgehog signalling inhibitor, attenuates carbon tetrachloride-induced liver fibrosis in rats

BACKGROUND AND PURPOSE

Liver fibrosis is one of the leading causes of morbidity and mortality worldwide with very limited therapeutic options. Given the pivotal role of activated hepatic stellate cells in liver fibrosis, attention has been directed towards the signalling pathways underlying their activation and fibrogenic functions. Recently, the hedgehog (Hh) signalling pathway has been identified as a potentially important therapeutic target in liver fibrosis. The present study was designed to explore the antifibrotic effects of the potent Hh signalling inhibitor, forskolin, and the possible molecular mechanisms underlying these effects.

EXPERIMENTAL APPROACH

Male Sprague-Dawley rats were treated with either CCl₄ and/or forskolin for 6 consecutive weeks. Serum hepatotoxicity markers were determined, and histopathological evaluation was performed. Hepatic fibrosis was assessed by measuring α-SMA expression and collagen deposition by Masson's trichrome staining and hydroxyproline content. The effects of forskolin on oxidative stress markers (GSH, GPx, lipid peroxides), inflammatory markers (NF-κB, TNF-α, COX-2, IL-1β), TGF-β1 and Hh signalling markers (Ptch-1, Smo, Gli-2) were also assessed.

KEY RESULTS

Hepatic fibrosis induced by CCl₄ was significantly reduced by forskolin, as indicated by decreased α-SMA expression and collagen deposition. Forskolin co-treatment significantly attenuated oxidative stress and inflammation, reduced TGF-β1 levels and down-regulated mRNA expression of Ptch-1, Smo and Gli-2 through cAMP-dependent PKA activation.

CONCLUSION AND IMPLICATIONS

In our model, forskolin exerted promising antifibrotic effects which could be partly attributed to its antioxidant and anti-inflammatory effects, as well as to its inhibition of Hh signalling, mediated by cAMP-dependent activation of PKA.

Redox Status in Patients with Femoral Neck Fractures

The femur transfers the body weight from the pelvic bone to the shinbone. Femur fractures are a significant cause of morbidity and mortality among the group of locomotor apparatus injuries, especially in the elderly population. Considering that oxidative stress occurs as a result of increased production of free radicals that damage cell function and cause numerous pathological conditions and diseases, the aim of this study was to investigate oxidative stress parameters in older patients with femoral neck fractures. This clinical study included 70 patients, of which 35 had femoral neck fractures (26 males and 9 females), while the other half of the patients formed the matched control group. Markers of oxidative stress (NO2 −, TBARS, H2O2 and O2 -) and anti-oxidative enzymes (SOD, CAT, and GSH) were measured. Results showed that the levels of O2 - increased, while levels of NO2 -, H2O2 and all the antioxidative enzymes decreased in patients with femoral neck fractures. These findings indicate that fractures cause oxidative stress, probably because of the reduced activity of osteoblasts and the increased activity of osteoclasts.

Turmeric extract and its active compound, curcumin, protect against chronic CCl4-induced liver damage by enhancing antioxidation

Background

Curcumin, a major active component of turmeric, has previously been reported to alleviate liver damage. Here, we investigated the mechanism by which turmeric and curcumin protect the liver against carbon tetrachloride (CCl₄)-induced injury in rats. We hypothesized that turmeric extract and curcumin protect the liver from CCl₄-induced liver injury by reducing oxidative stress, inhibiting lipid peroxidation, and increasing glutathione peroxidase activation.

Methods

Chronic hepatic stress was induced by a single intraperitoneal injection of CCl₄ (0.1 ml/kg body weight) into rats. Turmeric extracts and curcumin were administered once a day for 4 weeks at three dose levels (100, 200, and 300 mg/kg/day). We performed ALT and AST also measured of total lipid, triglyceride, cholesterol levels, and lipid peroxidation.

Result

We found that turmeric extract and curcumin significantly protect against liver injury by decreasing the activities of serum aspartate aminotransferase and alanine aminotransferase and by improving the hepatic glutathione content, leading to a reduced level of lipid peroxidase.

Conclusions

Our data suggest that turmeric extract and curcumin protect the liver from chronic CCl₄-induced injury in rats by suppressing hepatic oxidative stress. Therefore, turmeric extract and curcumin are potential therapeutic antioxidant agents for the treatment of hepatic disease.

Electronic supplementary material

The online version of this article (doi:10.1186/s12906-016-1307-6) contains supplementary material, which is available to authorized users.

Adverse outcome pathway development from protein alkylation to liver fibrosis

In modern toxicology, substantial efforts are undertaken to develop alternative solutions for in vivo toxicity testing. The adverse outcome pathway (AOP) concept could facilitate knowledge-based safety assessment of chemicals that does not rely exclusively on in vivo toxicity testing. The construction of an AOP is based on understanding toxicological processes at different levels of biological organisation. Here, we present the developed AOP for liver fibrosis and demonstrate a linkage between hepatic injury caused by chemical protein alkylation and the formation of liver fibrosis, supported by coherent and consistent scientific data. This long-term process, in which inflammation, tissue destruction, and repair occur simultaneously, results from the complex interplay between various hepatic cell types, receptors, and signalling pathways. Due to the complexity of the process, an adequate liver fibrosis cell model for in vitro evaluation of a chemical's fibrogenic potential is not yet available. Liver fibrosis poses an important human health issue that is also relevant for regulatory purposes. An AOP described with enough mechanistic detail might support chemical risk assessment by indicating early markers for downstream events and thus facilitating the development of an in vitro testing strategy. With this work, we demonstrate how the AOP framework can support the assembly and coherent display of distributed mechanistic information from the literature to support the use of alternative approaches for prediction of toxicity. This AOP was developed according to the guidance document on developing and assessing AOPs and its supplement, the users' handbook, issued by the Organisation for Economic Co-operation and Development.

Indigofera oblongifolia Prevents Lead Acetate-Induced Hepatotoxicity, Oxidative Stress, Fibrosis and Apoptosis in Rats

The current study was aimed to evaluate the preventive effects of Indigofera oblongifolia leaf extract (IOLE) on lead acetate (PbAc)-induced hepatotoxicity in adult male Wistar rats. PbAc was intraperitoneally injected at a dose of 20 mg/kg body weight for 5 days alone or in combination with the IOLE (100 mg/kg). Liver lead concentration and oxidative stress markers such as lipid peroxidation, hydrogen peroxide, nitric oxide, and glutathione content were investigated in addition to the enzymatic antioxidant activities. PbAc injection caused a significant elevation in the liver function parameters, lead level, lipid peroxidation, hydrogen peroxide, and nitric oxide, with a concomitant decline in the glutathione content compared with the control, accompanied by a significant inhibition of antioxidant enzyme activities. The induction of oxidative stress, lead accumulation, and histological alterations in the liver were successfully minimized by pre-administration of IOLE. In addition, the PbAc group showed increase in the levels of Bax, caspase-3, and matrix metalloproteinase-9 proteins, while the expression of Bcl-2 protein was decreased. Prior administration of IOLE significantly mitigated apoptosis and fibrosis in the liver. Finally, the major components in I. oblongifolia extract were identified as polyphenols, flavonoids, and organic acids using liquid chromatography coupled mass spectroscopy. Thus, the findings of the current study revealed that I. oblongifolia had protective, anti-fibrotic, antioxidant, and anti-apoptotic activities on PbAc-induced hepatotoxicity. The beneficial effects of I. oblongifolia were in part mediated by Nrf2/HO-1 pathway.

Rice Germosprout Extract Protects Erythrocytes from Hemolysis and the Aorta, Brain, Heart, and Liver Tissues from Oxidative Stress In Vitro

Identifying dietary alternatives for artificial antioxidants capable of boosting antihemolytic and antioxidative defense has been an important endeavor in improving human health. In the present study, we studied antihemolytic and antioxidative effects of germosprout (i.e., the germ part along with sprouted stems plus roots) extract prepared from the pregerminated rice. The extract contained considerable amounts of antioxidant β-carotene (414 ± 12 ng/g of extract) and phytochemicals such as total polyphenols (12.0 ± 1.1 mg gallic acid equivalent/g of extract) and flavonoids (11.0 ± 1.4 mg catechin equivalent/g of extract). The antioxidant potential of the extract was assessed by its DPPH- (2,2-diphenyl-1-picrylhydrazyl-) free radical scavenging activity where we observed that germosprout extract had considerable antioxidative potentials. To evaluate antihemolytic effect of the extract, freshly prepared erythrocytes were incubated with either peroxynitrite or Fenton's reagent in the absence or presence of the extract. We observed that erythrocytes pretreated with the extract exhibited reduced degree of in vitro hemolysis. To support the proposition that germosprout extract could act as a good antioxidative agent, we also induced in vitro oxidative stress in erythrocyte membranes and in the aorta, brain, heart, and liver tissue homogenates in the presence of the extract. As expected, germosprout extract decreased oxidative stress almost to the same extent as that of vitamin E, as measured by lipid peroxide levels, in all the mentioned tissues. We conclude that rice germosprout extract could be a good natural source of antioxidants to reduce oxidative stress-induced hemolysis and damage of blood vessels and other tissues.

Amomum cardamomum L. ethyl acetate fraction protects against carbon tetrachloride-induced liver injury via an antioxidant mechanism in rats

Background

Medicinal herb-derived drug development has become important in the relief of liver pathology. Amomun cardamomum is traditionally used therapeutically in Korea to treat various human ailments including dyspepsia, hiccupping, and vomiting. We investigated to assess the protective effect of A. cardamomum on carbon tetrachloride (CCl₄)-induced liver damage through antioxidant activity in hepatic tissues of Sprague–Dawley rats.

Methods

Antioxidant properties of different fractions from A. cardamomum from ethanol extracts were evaluated by an in vitro free radical scavenging systems. The protective effect of the ethyl acetate fraction from A. cardamomum (EAAC) against CCl₄-induced cytotoxicity was determined by a cell viability assay using HepG2 hepatocarcinoma cells. In vivo study, the influence of EAAC concentrations of 100 and 200 mg/kg following CCl₄-induced hepatic injury was assessed. Serum levels of glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), and alkaline phosphatase (ALP) were determined, as was lipid peroxidation (malondialdehyde, MDA). Effect of EAAC on liver detoxification enzymes including superoxide dismutase (SOD), total glutathione (GSH), and glutathione S-transferase (GST) activity was measured in rat liver homogenates. Liver cytochrome P450 (CYP2E1) expression level was determined by quantification of mRNA.

Results

Phytochemical analysis of A. cardamomum indicated that EAAC was enriched in total polyphenol and total flavonoid. Most of the tannins were confined to the hexane fraction. Hepatoprotective properties of EAAC were evident, with significantly reduced serum levels of GOT, GPT, and ALP compared with the control group. Improved hepatic antioxidant status was evident by increased SOD, GSH, and GST enzymes in rat liver tissue. Liver lipid peroxidation induced by CCl₄ was apparent by increased intracellular MDA level. EAAC suppressed lipid peroxidation as evidenced by the significant decrease in MDA production. Expression of CYP2E1 was also significantly decreased at the higher concentration of EAAC, indicating the hepatoprotective efficacy of EAAC on acute liver damage.

Conclusion

These results indicated that EAAC has a significant hepatoprotective activity on CCl₄-induced acute hepatic injury in rats, which might be derived from its antioxidant properties and CYP2E1 downregulation.

Carnosic acid nanoparticles suppress liver ischemia/reperfusion injury by inhibition of ROS, Caspases and NF-κB signaling pathway in mice

Living donor liver transplantation (LDLT) requires ischemia/reperfusion (I/R), which can lead to early graft injury. However, the detailed molecular mechanism of I/R injury remains unclear. Carnosic acid, as a phenolic diterpene with function of anti-inflammation, anti-cancer, anti-bacterial, anti-diabetic, as well as neuroprotective properties, is produced by many species from Lamiaceae family. Nanoparticulate drug delivery systems have been known to better the bioavailability of drugs on intranasal administration compared with only drug solutions. Administration of carnosic acid nanoparticles was thought to be sufficient to lead to considerable inhibition of liver injury progression induced by ischemia/reperfusion. In our study, liver ischemia/reperfusion injury was established successfully with C57BL/6 animal model. 10 and 20mg/kg carnosic acid nanoparticles were injected to mice for five days prior to ischemia. After liver ischemia/reperfusion, the levels of serum AST, ALT and APL were increased, which was attenuated by pre-treatment with carnosic acid nanoparticles. In addition, carnosic acid nanoparticles inhibited ROS production via its related signals regulation. And carnosic acid nanoparticles also suppressed the ischemia/reperfusion-induced up-regulation in the pro-apoptotic protein and mRNA levels of Bax, Cyto-c, Apaf-1 and Caspase-9/3 while increased ischemia/reperfusion-induced decrease of anti-apoptotic factor of Bcl-2. Further, ischemia/reperfusion-induced inflammation was also inhibited for carnosic acid nanoparticles administration via inactivating NF-κB signaling pathway, leading to down-regulation of pro-inflammatory cytokines releasing. In conclusion, our study suggested that carnosic acid nanoparticles protected against liver ischemia/reperfusion injury via its role of anti-oxidative, anti-apoptotic and anti-inflammatory bioactivity.

Comparative study of antifibrotic activity of some magnesium-containing supplements on experimental liver toxicity. Molecular study

INTRODUCTION

Liver fibrosis is the excessive accumulation of extracellular matrix (ECM) proteins including collagen that occurs in most types of chronic liver diseases. This study aimed to investigate and compare the therapeutic efficacy of different magnesium (Mg)-containing supplements (formulations A, B, and C) on carbon tetrachloride (CCl₄)-induced liver fibrosis in rats.

METHODS

Liver fibrosis was induced by intraperitoneal injection of rats with CCl₄ (1:1 in olive oil, 2 mL/kg, three times/week) for 4 weeks, and then rats were orally treated with different Mg-containing supplements (formulations A, B, and C) once daily for another one month. Liver fibrosis was quantified by evaluation of expressions of Collagen I, transforming growth factor β-1 (TGFβ1), platelet-derived growth factor-C (PDGF-C), nuclear factor kappa-β (NF-κβ), and measurement of hepatic collagen (hydroxyproline) level. Also, malondialdehyde (MDA), nitric oxide (NO), glutathione (GSH) level, superoxide dismutase (SOD), and glutathione-S-transferase (GST) activities were estimated.

RESULTS

CCl₄ administration significantly elevated expressions of the studied genes, hepatic hydroxyproline, MDA, and NO levels and caused depletion of GSH level, decreased SOD, and GST activities when compared with those of their corresponding control, p < 0.05. All magnesium supplements significantly inhibited expressions of the studied genes and attenuated the hepatic hydroxyproline level as compared with those of CCl₄-treated group_; p < 0.05; for NF-κβ, the highest inhibition was by formulations B and C. Regarding Collagen I, TGFβ1, and hepatic hydroxyproline content, the highest inhibition was by Formulation C, and Formulation A revealed highest inhibition for PDGF-C. All magnesium supplements revealed normalization of oxidant and antioxidants parameters. Histopathological examination supports the biochemical and molecular findings.

CONCLUSION

Mg supplements were effective in the treatment of hepatic CCl₄-induced fibrosis-rat model.

Correlation between vitamin D levels and apoptosis in geriatric patients infected with hepatitis C virus genotype 4

Background

Vitamin D levels play a pivotal role in most biological processes and differ according to age. A deficiency of vitamin D in chronic hepatitis C (CHC) patients has been shown to be linked with the severity of liver fibrosis, but little is known about the mechanism of this association.

Objective

In this study, we evaluate the potential interrelation between vitamin D levels, oxidative stress, and apoptosis, based on liver fibrosis in geriatric patients infected with hepatitis C virus (HCV) genotype 4.

Subjects and methods

A total of 120 adult individuals aged 30–68 years were recruited in this study. Of these, 20 healthy subjects (15 men and five women) with a mean age of 48.3±6.1 years were selected as controls, and 100 patients with a mean age of 47.8±4.9 years with chronic HCV (CHC) who had undergone liver biopsy (80 men and 20 women) were included in this study. Based on liver radiographic (computed tomography, magnetic resonance imaging) and histological Metavir system analyses, the CHC patients were classified into three groups: asymptomatic CHC carriers (n=30), fibrosis (n=25), and cirrhosis (n=45). HCV RNA, HCV genotypes, inflammatory cytokines AFP and TNFα, 25-hydroxyvitamin D (25[OH]D) levels, apoptotic markers single-stranded DNA (ssDNA) and soluble Fas (sFas), and oxidative stress markers nitric oxide (NO) and total antioxidant capacity (TAC) were estimated by using molecular, immunoassay, and colorimetric techniques.

Results

Approximately 30% of the study population (n=30) were diagnosed as asymptomatic CHC carriers, and 70% of the study population (n=70) had severe fibrosis; these were classified into fibrosis and cirrhosis. There was a significant reduction in 25(OH)D levels and TAC activity, along with an increase in levels of NO, AFP, TNFα, ssDNA, and sFas in fibrosis and cirrhosis subjects compared with those of asymptomatic CHC carriers and health controls. The deficiency in 25(OH)D levels correlated positively with sFas, ssDNA, AFP, TNFα, NO, and TAC, and negatively with age, sex, liver function, body mass index, homeostatic model assessment – insulin resistance, HCV RNA, and viral load. Significant intercorrelation was reported between serum 25(OH)D concentrations and apoptotic and oxidative markers, which suggested progression of liver pathogenesis and fibrogenesis via oxidative and apoptotic mechanisms.

Conclusion

The data showed that vitamin D status was significantly correlated with pathogenesis and fibrogenesis of the liver in geriatric patients infected with HCV genotype 4. The deficiency in 25(OH)D levels was shown to have a pivotal role in the pathogenesis of liver via apoptotic, oxidative stress, and inflammatory mechanistic pathways. The data point to adequate vitamin D levels being recommended for a good response to treatment strategies, especially in older CHC patients.

Procoagulant changes in fibrin clot structure in patients with cirrhosis are associated with oxidative modifications of fibrinogen

Essentials Patients with cirrhosis have hemostatic changes, which may contribute to a risk of thrombosis. This in vitro study compares clot formation and structure between patients and healthy subjects. Clot formation is delayed in patients; ultimately, however, clot permeability is decreased. The thrombogenic structure of fibrin clots may contribute to the thrombotic risk in cirrhosis.

ABSTRACT

Background and Objectives Patients with cirrhosis can be at risk of thrombotic complications due to an imbalance between hemostatic components. However, little is known on how the disease affects clot generation or how alterations in the structure of fibrin clots may affect the hemostatic function of these patients. Methods We investigated the formation and structure of clots generated with plasma and purified fibrinogen of 42 patients with cirrhosis. Clots generated with plasma and fibrinogen of 29 healthy volunteers were studied for comparison. Clot formation and structure were assessed by turbidity, permeation studies, confocal laser and scanning electron microscopy (SEM). The extent of fibrinogen oxidation was assessed by measuring the carbonyl content of purified fibrinogen samples. Results Tissue factor and thrombin-induced clotting of plasma was delayed in patients. The clotting rate was also decreased, but change in turbidity, fibrin density and fiber thickness were largely comparable to healthy volunteers. Conversely, clot permeability was significantly decreased in patients. When clots were generated with purified fibrinogen, differences in clot formation and structure similar to those in plasma were found. The carbonyl content was increased in patient fibrinogen and correlated with disease severity and clot permeability. Conclusions Delayed clot formation in cirrhosis ultimately results in decreased clot permeability. Similar alterations in clots generated with purified fibrinogen suggest that modifications of the molecule are (partly) responsible. Taken together, these findings are indicative of hypercoagulable features of clots of patients with cirrhosis, which may explain the increased risk of thrombosis associated with this condition.

Novel roles for AhR and ARNT in the regulation of alcohol dehydrogenases in human hepatic cells

The mechanisms by which pollutants participate in the development of diverse pathologies are not completely understood. The pollutant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) activates the AhR (aryl hydrocarbon receptor) signaling pathway. We previously showed that TCDD (25 nM, 30 h) decreased the expression of several alcohol metabolism enzymes (cytochrome P450 2E1, alcohol dehydrogenases ADH1, 4 and 6) in differentiated human hepatic cells (HepaRG). Here, we show that, as rapidly as 8 h after treatment (25 nM TCDD) ADH expression decreased 40 % (p < 0.05). ADH1 and 4 protein levels decreased 40 and 27 %, respectively (p < 0.05), after 72 h (25 nM TCDD). The protein half-lives were not modified by TCDD which suggests transcriptional regulation of expression. The AhR antagonist CH-223191 or AhR siRNA reduced the inhibitory effect of 25 nM TCDD on ADH1A, 4 and 6 expression 50-100 % (p < 0.05). The genomic pathway (via the AhR/ARNT complex) and not the non-genomic pathway involving c-SRC mediated these effects. Other AhR ligands (3-methylcholanthrene and PCB 126) decreased ADH1B, 4 and 6 mRNAs by more than 78 and 55 %, respectively (p < 0.01). TCDD also regulated the expression of ADH4 in the HepG2 human hepatic cell line, in primary human hepatocytes and in C57BL/6J mouse liver. In conclusion, activation of the AhR/ARNT signaling pathway by AhR ligands represents a novel mechanism for regulating the expression of ADHs. These effects may be implicated in the toxicity of AhR ligands as well as in the alteration of ethanol or retinol metabolism and may be associated further with higher risk of liver diseases or/and alcohol abuse disorders.

Liver Disease in Pediatric Patients With Ataxia Telangiectasia: A Novel Report

OBJECTIVE

Ataxia telangiectasia (A-T) is a rare genetic multiorgan disease. Although gastrointestinal involvement is known, hepatic involvement in A-T has not been investigated. We aimed to study the hepatic involvement in a large cohort of patients with A-T.

METHODS

A retrospective review of patients, studied from January 1986 to January 2015 at a National A-T Center. Clinical data including demographic, genetic, laboratory, nutritional, radiographic, and histological data were retrieved.

RESULTS

Fifty-three patients, 27 (49%) boys, age 14.6 ± 5.2 years (range 5.9-26.1 years), were included. Twenty-three patients (43.4%), age 9.9 ± 5.1 years, had consistently abnormal liver enzymes. The mean enzyme levels were alanine aminotransferase 76.8 ± 73.8 IU/L, aspartate aminotransferase 70 ± 50 IU/L, alkaline phosphatase 331 ± 134 IU/L, and gamma glutamyl transferase 114.7 ± 8 IU/L. Evaluation of other etiology of liver disease was negative. Ultrasonography revealed fatty liver in 9 of them (39%). Liver biopsy was performed in 2 patients, revealing mild-to-moderate steatosis in both, and fibrosis in 1 patient. Progression to advanced liver disease occurred in 2 of 23 (9%) patients within 2 to 5 years. Dyslipidemia was significantly associated with abnormal liver enzymes: 3 of 30 (10%) patients without abnormal liver enzymes versus 10 of 23 (45.5%) patients with abnormal liver enzymes, respectively (P < 0.05, Fisher exact test). No correlation was found between hepatic involvement and HbA1C, sex, presence of malignancy, or type of mutation.

CONCLUSIONS

Abnormal liver enzymes and fatty liver are common in patients with A-T and may progress to advanced liver disease at a young age. These findings are novel and implicate that patients with A-T with abnormal liver enzymes should be evaluated for the presence of liver disease.

Dietary Flavonoid Hyperoside Induces Apoptosis of Activated Human LX-2 Hepatic Stellate Cell by Suppressing Canonical NF-κB Signaling

Hyperoside, an active compound found in plants of the genera Hypericum and Crataegus, is reported to exhibit antioxidant, anticancer, and anti-inflammatory activities. Induction of hepatic stellate cell (HSC) apoptosis is recognized as a promising strategy for attenuation of hepatic fibrosis. In this study, we investigated whether hyperoside treatment can exert antifibrotic effects in human LX-2 hepatic stellate cells. We found that hyperoside induced apoptosis in LX-2 cells and decreased levels of α-smooth muscle actin (α-SMA), type I collagen, and intracellular reactive oxygen species (ROS). Remarkably, hyperoside also inhibited the DNA-binding activity of the transcription factor NF-κB and altered expression levels of NF-κB-regulated genes related to apoptosis, including proapoptotic genes Bcl-Xs, DR4, Fas, and FasL and anti-apoptotic genes A20, c-IAP1, Bcl-X_L, and RIP1. Our results suggest that hyperoside may have potential as a therapeutic agent for the treatment of liver fibrosis.