Hepatic Glutathione Levels Research Articles

Modulation of steroidogenesis by Actaea racemosa and vitamin C combination, in letrozole induced polycystic ovarian syndrome rat model: promising activity without the risk of hepatic adverse effect

BackgroundComplementary remedies such as the Chinese herb ‘Sheng Ma’ (Black cohosh; Actaea racemosa ‘AR’) are being sought to overcome the shortcomings of conventional hormonal and surgical therapies developed for the treatment of polycystic ovary syndrome (PCOS). However, AR-induced hepatotoxicity necessitates a cautionary warning to be labeled on its products as recommended by the United States Pharmacopeia, where four out of seven hepatotoxic cases in Sweden were possibly associated with black cohosh products.MethodsWe investigated the effects, safety, and molecular targets of black cohosh ethanolic extract and/or vitamin C on ovarian functionality and oxidative response in hyperandrogenism-induced PCOS rats. A well-established rat model using oral letrozole, daily, for 21 days was employed. The rats then received the AR extract with and without vitamin C for 28 days. The hormonal evaluation, antioxidant status, histopathological examination, immunohistochemical analysis, cell proliferation, and the expression ratio of the aromatase (Cyp19α1) gene were evaluated. Additionally, holistic profiling of the AR arsenal of secondary metabolites was performed using ultra-high-performance liquid chromatography (UHPLC) coupled with quadrupole high-resolution time of flight mass spectrometry (QTOF-MS).ResultsBeneficial effects were exerted by AR in PCOS rats as antioxidant status, hormonal profile, lipid profile, glucose level, liver functions, and the induced Ki-67 expression in the granulosa, theca cell layers and interstitial stromal cells were all improved. Notably, the combination of AR with vitamin C was not only more effective in reversing the dysregulated levels of testosterone, luteinizing hormone, and mRNA level of Cyp19α1 gene in the PCOS rat, but also safer. The combination regulated both ovarian and hepatic malondialdehyde (MDA) and glutathione (GSH) levels with histological improvement observed in the liver and ovaries. In addition, the untargeted metabolomic profiling enabled the identification of 61 metabolites allocated in five major chemical classes.ConclusionThis study demonstrated the benefit of the combinatorial effects of AR and vitamin C in mitigating the reproductive and metabolic disorders associated with PCOS with the elimination of AR hepatotoxic risk.

Evaluation of the nephroprotective effect of the essential oil of Haloxylon articulatum in Wistar rats intoxicated by Nickel

Nickel compounds are environmental hazards, capable of inducing severe health problems and carcinogenic effects, which can be mitigated by numer-ous antioxidants. Therefore, the aim of this study was to determine the pro-tective effect of Haloxylon articulatum essential oil (HAOA) by intraperitone-al injection of 0.1 ml/kg/day for a period of 21 days, against nickel-induced nephrotoxicity in Wistar rats. The extraction of the essential oil of H. articula-tum allowed us to obtain an EOHA with a yield of 0.11% and the characteri-zation of the plant by GC-MS indicatedthat the major components of this extract are Thymol (14, 19%), Alphaterpinene (11.02), ß -E-Ocimene (9.64), 1,8-Cineole (8.69), Oleuropine (5.17%), Linalol (5.12%), Delta -3- Carene (4.12). The results obtained showed a decrease in corprel weight and kidney weight in nickel poisoned rats. Biochemical biomarkers of renal function fol-lowing nickel exposure were demonstrated by significant increases in serum urea, uric acid and creatinine concentrations. The toxic effect of nickel was also indicated by a significant decrease in the enzymatic activity of catalase (CAT), glutathione peroxidase (GPx) and hepatic glutathione levels (GSH). All these variations in biochemical parameters were confirmed by histopatho-logical observations of the kidneys; glomerular necrosis with degeneration of the Bowman's capsule in comparison with the control rats. In addition, EOHA administration resulted in an increase in body and kidney weight of the rats compared to the poisoned rats. The results of the renal biochemical assays show a correction of the values following the administration of EOHA com-pared to those of the poisoned animals. Analysis of the antioxidant status in the kidney indicates that EOHA has restored the activity of the oxidative sta-tus. In fact, the histological study carried out showed a clear improvement in renal tissue architecture in poisoned rats treated with EOHA, which justifies the great importance of H. articulatum in traditional medicine and its thera-peutic virtues.

GC/MS-Based Metabolomics Profiling Approach and Determination of Ameliorative effect of Chiliadenus montanus extract towards CCl4 induced Hepatotoxicity in Albino Rats

The current study aimed to evaluate the GC/MS profiling of Chiliadenus montanus leaves extract which consists of 48 compounds, nine of them are major and represented 52.55 % from the total peak areas. The ameliorative effect towards the CCl4-induced hepatotoxicity in male Wistar rats through measuring certain biochemical parameters content in the liver were analyzed. CCl4 diluted 1:9 (v/v) in olive oil was injected intraperitoneally followed by oral administration of methanolic plant extract (200 mg/kg body weight). The CCl4-treated rats showed a significant decline in the studied hematological parameters, the serum levels of high-density lipoprotein (HDL), albumin (A) as well as the hepatic levels of glutathione (GSH) and activities of catalase (CAT), superoxide dismutase (SOD) , glutathione reductase (GR), elevation in the levels of total lipids (TL), triglycerides (TG), total cholesterol (TC), low-density lipoproteins (LDL), globulin (G), total bilirubin (TBil) , alanine and aspartate aminotransferase and alkaline phosphatase (ALAT and ASAT, ALP) and the hepatic levels of malondialdehyde (MDA). In contrast, the administration of methanol extract, notably improved all the studied parameters. This study showed that CCl4 administration to Wistar rats, at a high dose level, could induce a hepatic injury in addition to certain hematologic and metabolic alterations. The work was extended to examine tissue histopathology. In conclusion, C. montanus leaves methanol extract, resulted in an attractive candidate for ameliorating of hepatotoxicity induced by CCl4 through scavenging free radicals, improved liver functions, and normalizing the liver histopathological architecture. Yet, the treatment with methanol extract could ameliorate these alterations via their antioxidative effect. Further studies are required in order to identify the molecules responsible of the pharmacological activities.

Kaempferol suppresses acetaminophen-induced liver damage by upregulation/activation of SIRT1

Context Kaempferol, a flavonoid glycoside, has many hepatoprotective effects in several animals due to its antioxidant potential. Objective This study evaluated the hepatoprotective effect of kaempferol against acetaminophen (APAP)-induced liver damage and examined whether the protection involved modulation of silent information regulator 1 (SIRT1) signalling. Materials and methods Adult male Wistar rats were classified into four groups (n = 8) and treated as follows: control + normal saline (vehicle), control + kaempferol (250 mg/kg), APAP (800 mg/kg, a single dose) and APAP + kaempferol. Kaempferol was administered for the first seven days followed by administration of APAP. The study was ended 24 h after APAP administration. Results At the histological level, kaempferol reduced liver damage in APAP-treated rats. It also reduced the hepatic levels of TNF-α (66.3%), IL-6 (38.6%) and protein levels of caspase-3 (88.2%), and attenuated the increase in circulatory serum levels of ALT (47.6%), AST (55.8%) and γ-GT (35.2%) in APAP-treated rats. In both the controls and APAP-treated rats, kaempferol significantly increased the hepatic levels of glutathione (GSH) and superoxide dismutase, suppressed MDA and reactive oxygen species (ROS) levels, increased protein levels of Bcl-2 and downregulated protein levels of Bax and cleaved Bax. Concomitantly, it reduced the expression of CYP2E1, and the activity and protein levels of SIRT1. Consequently, it decreased the acetylation of all SIRT1 targets including PARP1, p53, NF-κB, FOXO-1 and p53 that mediate antioxidant, anti-inflammatory and anti-apoptotic effects. Discussion and conclusions This study encourages the use of kaempferol in further clinical trials to treat APAP-induced hepatotoxicity.

The effects of chitosan-vitamin C nanocomposite supplementation on the growth performance, antioxidant status, immune response, and disease resistance of Nile tilapia (Oreochromis niloticus) fingerlings

This study was performed to investigate the effect of the dietary supplementation of chitosan-vitamin C nanocomposite (CVCN) at four different concentrations (0, 200, 300, 400 mgkg−1 diet) in Nile tilapia (Oreochromis niloticus) fingerlings, for ten weeks feeding period, on the growth performance, antioxidant activity, immune status, histopathology of some organs, and disease resistance against Aeromonas sobria (A. sobria). A total of 180 fingerlings (average initial weight = 14.74 ± 0.016 g) were randomly allotted to four groups. Different concentrations of CVCN significantly increased the final body weight, body weight gain, feed conversion ratio, the protein efficiency ratio, specific growth rate%, and daily weight gain in a dose-dependent manner (P < 0.05). A significant increase (P = 0.03) in the serum vitamin C level was observed at the highest concentration (400 mgkg−1) of CVCN. A significant increase (P = 0.00) in the serum growth hormone level was observed at all concentrations of CVCN in a dose-dependent manner. There was a significant increase (P < 0.05) in the serum and hepatic levels of superoxide dismutase and glutathione, and decrease in serum Malondialdehyde, by increasing the level of vitamin supplementation compared to the zero level. Likewise, there was a significant increase (P < 0.05) in the serum levels of lysozyme, nitric oxide, relative percent survivability, and phagocytic percentage with an increase in the vitamin level, and the best results were observed at 400 mgkg−1CVCN. Histologically, CVCN increased the villus height, goblet cell count, and intra-epithelium lymphocytes of the proximal part of the intestine. Therefore, the dietary supplementation by CVCN improved the fish growth performance, and CVCN at 400 mgkg−1 the best dietary level of for O. niloticus fingerlings that exhibited improve the antioxidant status, intestinal histology, immune response, and disease resistance.

Dietary squalene supplementation alleviates diquat-induced oxidative stress and liver damage of broiler chickens

The aim of this study was to explore the protective effects of squalene supplementation on growth performance, oxidative status, and liver function of diquat-challenged broilers. One hundred forty-four 1-day-old male Ross 308 broiler chicks were allocated to 3 groups, and each group consisted of 6 replicates of 8 birds each. The three groups were as follows: 1) nonchallenged broilers fed with a basal diet (control group), 2) diquat-challenged broilers fed a basal diet, and 3) diquat-challenged broilers fed with a basal diet supplemented with 1.0 g/kg of squalene. Broilers were intraperitoneally injected with 20 mg/mL of diquat solution at a dosage of 1 mL/kg of BW or an equivalent amount of saline at 20 d. Compared with the control group, weight gain and BW change rate during 24 h after injection were decreased by diquat challenge (P < 0.05), and the diquat-induced compromised growth performance was improved by squalene supplementation (P < 0.05). Diquat administration reduced plasma superoxide dismutase activity and increased malondialdehyde accumulation and glutathione peroxidase activity in both plasma and the liver (P < 0.05). In contrast, plasma glutathione peroxidase activity in diquat-challenged broilers was reduced by squalene supplementation (P < 0.05). The hepatic glutathione level was reduced by diquat administration (P < 0.05), whereas its level in plasma and the liver of diquat-challenged broilers was increased by squalene supplementation (P < 0.05). The relative liver weight of broilers was increased by diquat challenge (P < 0.05), with its value being intermediate in the squalene-supplemented group (P > 0.05). The plasma aminotransferase activities and total bilirubin concentration were increased by diquat challenge (P < 0.05), which were reduced by squalene supplementation (P < 0.05). The mRNA abundance of hepatic nuclear factor erythroid 2–related factor 2 (P < 0.05) was upregulated by diquat treatment, regardless of squalene supplementation. The mRNA abundance of hepatic glutathione peroxidase 1 and B-cell lymphoma/leukemia 2–associated X protein was upregulated by diquat challenge (P < 0.05), which was reversed by squalene administration (P < 0.05). Squalene increased NAD(P)H quinone dehydrogenase 1 mRNA abundance and decreased caspase 3 mRNA abundance in the liver of diquat-challenged broilers (P < 0.05). The results suggested that squalene can increase weight gain, improve oxidative status, and alleviate liver injury in diquat-challenged broilers.

The synthetic toxin biliatresone causes biliary atresia in mice

AbstractExposure to environmental toxins may be responsible for biliary atresia. The focus of this study was to investigate the effect of biliatresone on the development of the hepatobiliary system in mice. We successfully synthesized biliatresone with a purity of 98% and confirmed its biliary toxicity. Exposure to high doses of biliatresone caused abortion or death in pregnant mice. Neonatal mice injected with biliatresone developed clinical signs of biliary obstruction, and dysplasia or the absence of extrahepatic biliary tract lumen, which confirmed the occurrence of biliary atresia. In the portal tract of biliary atresia mice, signs of infiltration of inflammatory cells and liver fibrosis were observed. The signature of extrahepatic biliary gene expression in these mice mainly involved the cell adhesion process, and hepatic RNA-seq was highly linked to transcriptional evidence of oxidative stress. When compared with the control group, hepatic glutathione levels were markedly reduced after biliatresone injection. Taken together, these data confirm that biliatresone causes severe developmental abnormalities of the hepatobiliary system in mice. Furthermore, decreased levels of glutathione may play a mechanistic role in the pathogenesis of liver fibrosis in biliatresone-induced experimental biliary atresia.The authors show that exposure of neonatal mice to the toxin biliatresone creates an animal model of biliary atresia. Such mice develop clinical signs of biliary obstruction, inflammatory cell infiltration and liver fibrosis.

Inhibition of γ-glutamyltransferase ameliorates ischaemia-reoxygenation tissue damage in rats with hepatic steatosis.

Hepatic steatosis may be associated with an increased γ-glutamyltransferase (γ-GT) levels. Ischaemia-reoxygenation (IR) injury causes several deleterious effects. We evaluated the protective effects of a selective inhibitor of γ-GT in experimentally induced IR injury in rats with obesity and steatosis. Otsuka Long-Evans Tokushima Fatty (OLETF) rats with hepatic steatosis were used in the current study. The portal vein and hepatic artery of left lateral and median lobes were clamped to induce ischaemia. Before clamping, 1 ml of saline (IR group) or 1-ml saline containing 1 mg·kg-1 body weight of GGsTop (γ-GT inhibitor; IR-GGsTop group) was injected into the liver via the inferior vena cava. Blood flow was restored after at 30 min of the start of ischaemia. Blood was collected before, at 30 min after ischaemia and at 2 h and 6 h after reoxygenation. All the animals were killed at 6 h and the livers were collected. Treatment with GGsTop resulted in significant reduction of serum ALT, AST and γ-GT levels and hepatic γ-GT, malondialdehyde, 4-hydroxy-2-nonenal and HMGB1 at 6 h after reoxygenation. Inhibition of γ-GT retained normal hepatic glutathione levels. There was prominent hepatic necrosis in IR group, which is significantly reduced in IR-GGsTop group. Treatment with GGsTop significantly increased hepatic glutathione content, reduced hepatic MDA, 4-HNE and HMGB1 levels and, remarkably, ameliorated hepatic necrosis after ischaemia-reoxygenation. The results indicated that GGsTop could be an appropriate therapeutic agent to reduce IR-induced liver injury in obesity and steatosis.

Estrogen receptor agonists protect against acetaminophen-induced hepatorenal toxicity in rats

AimsAcetaminophen-induced hepatorenal toxicity varies among sexes with controversial results among species. The aim was to compare the impact of sex and ovarian hormones on hepatorenal toxicity and to elucidate protective effects of estrogen and estrogen receptor (ER) agonists. Main methodsUnder anesthesia, female rats underwent ovariectomy (OVX) or sham-OVX. Starting at postsurgical 40th day, OVX-rats received subcutaneously (each, 1 mg/kg/day) 17β-estradiol (E2), ERβ-agonist (DPN) or ERα-agonist (PPT) for 10 days, while male and sham-OVX rats received vehicle for 10 days. Then, rats received either acetaminophen (3 g/kg) or saline by orogastric gavage and were decapitated at 24th h. Blood samples were obtained to measure serum ALT, AST, BUN, creatinine levels. Liver and kidney samples were obtained for histopathologic examination and for analyzing levels of luminol- and lucigenin-chemiluminescence, glutathione and myeloperoxidase activity. Key findingsCompared to their control groups, levels of AST, ALT, BUN, creatinine, hepatic and renal myeloperoxidase activity and chemiluminescence levels were increased, and hepatic glutathione level was decreased in acetaminophen-administered male groups, while ALT and hepatic chemiluminescence levels were not elevated in sham-OVX-rats. Both ER-agonists and E2 reduced BUN, creatinine and reversed all oxidative parameters in renal tissues of OVX-rats. Additionally, ERα-agonist reversed all hepatic injury parameters, while ERβ-agonist elevated hepatic glutathione level. SignificanceAcetaminophen toxicity in female rats presented with a more preserved hepatic function, while renal toxicity was not influenced by sex or by the lack of ovarian hormones. Pretreatment with estrogen or ER agonists, via their antioxidant actions, provided protective effects on acetaminophen-induced hepatorenal toxicity.

Iron loading exerts synergistic action via a different mechanistic pathway from that of acetaminophen-induced hepatic injury in mice

Acetaminophen (APAP) overdose is a major cause of drug-induced acute liver failure. In such cases, free iron is released from lysosomes and is transported to mitochondria where it plays a pivotal role in APAP-induced liver injury. We previously reported that ascorbic acid (Asc) markedly mitigates APAP-induced hepatic damage in aldehyde reductase (Akr1a)-knockout (KO) mice that produce about 10% Asc as wild-type (WT) mice. However, the issue of the protective mechanism of Asc in association with the status of iron remains ambiguous. To gain additional insights into this issue, we examined effects of APAP (500 mg/kg) on female KO mice under conditions of iron loading. While the KO mice without AsA supplementation were more sensitive to APAP toxicity than the WT mice, FeSO4 loading (25 mg/kg) to WT mice aggravated the hepatic injury, which was a similar extent to that of the KO mice. Supplementation of Asc (1.5 mg/ml in the drinking water) ameliorated KO mice irrespective of iron status but did not change the iron-mediated increase in the lethality in the WT mice. Hepatic cysteine and glutathione levels declined to similar extents in all mouse groups at 3 h irrespective of the iron status and largely recovered at 18 h after the APAP treatment when liver damage was evident. Asc prominently mitigated APAP toxicity in KO mice irrespective of the iron status but had no effect on the synergistic action of iron and APAP in the WT mice, suggesting that the mechanism for the deteriorating action of loaded iron is different from that of APAP toxicity.

Protective effect of metformin on BPA-induced liver toxicity in rats through upregulation of cystathionine β synthase and cystathionine γ lyase expression

Human exposure to bisphenol A (BPA) is unavoidable in daily life. Recently, research has showen that BPA could induce oxidative imbalance, thereby causing reproductive toxicity and liver dysfunction. Accumulated evidence has demonstrated that metformin possesses strong anti-oxidative properties. This study aimed to study the mechanism underlying the hepatic-protective effect of metformin on liver injury induced by BPA in rats via the UPLC-MS/MS metabolomics approach. Forty-two male rats were randomly divided into six groups (n = 7), namely the saline group (control), the corn oil group (vehicle), the metformin group (Met), the bisphenol A group (BPA), the bisphenol A and metformin group (BPA + Met), and the bisphenol A and diammonium glycyrrhizinate (positive control) group (BPA + DG). Serum was collected for biochemical analysis and metabolomics, and liver tissue was collected for histopathology and metabolomics in each group. We found that metformin could significantly reduce the levels of liver function enzymes (ALT, AST and GGT) and ameliorate inflammatory cell infiltration and hepatocyte necrosis induced by BPA. On the other hand, metformin could significantly enhance the total antioxidant capacity in BPA rats. Notably, metabolomics data indicated that the principal altered metabolic pathways based on the 26 differential metabolites in liver tissue, and 21 in serum among vehicle, BPA and BPA + Met groups, respectively, including cysteine and methionine metabolism, glutathione metabolism, and arginine biosynthesis and purine metabolism. Additionally, metformin significantly increased cystathionine β synthase (CBS) and cystathionine γ lyase (CSE), thus reducing serum levels of homocysteine and increasing hepatic levels of cysteine and glutathione in BPA-treated rats. Overall, this study's results provided new insights into the role and mechanism of metformin in BPA-induced liver injury in rats.

Genistein and exercise modulated lipid peroxidation and improved steatohepatitis in ovariectomized rats

BackgroundThe prevalence of nonalcoholic steatohepatitis (NASH) in menopausal women is increasing, but current treatments have not been proven effective. The objective of this study was to investigate the treatment effects of genistein and running exercise in ovariectomized (OVX) rats with NASH.MethodsThirty-six female Sprague-Dawley rats were divided into 6 groups, control; OVX with standard diet; OVX with high fat and high fructose (HFHF) diet for 4 weeks; OVX with HFHF and genistein treatment (16 mg/kg BW/day) for 5 weeks (OVX + HFHF+GEN); OVX with HFHF and moderate intensity exercise for 5 weeks (OVX + HFHF+EX); OVX with HFHF and combined treatments (OVX + HFHF+GEN + EX). Serum interleukin-6 (IL-6) levels, hepatic free fatty acid (FFA), hepatic glutathione (GSH), and hepatic malondialdehyde (MDA) levels were measured. Liver histology was examined to determine NASH severity.ResultsOVX + HFHF group had the highest levels of hepatic FFA compared with OVX and control groups (5.92 ± 0.84 vs. 0.37 ± 0.01 vs. 0.42 ± 0.04 nmol/mg protein, respectively, p < 0.01). Serum IL-6 levels were significantly elevated in both OVX and OVX + HFHF groups as compared with controls (112.13 ± 6.50 vs. 121.47 ± 3.96 vs. 86.13 ± 2.40 pg/mL, respectively, p < 0.01). In OVX + HFHF group, hepatic MDA levels were higher, while GSH levels were lower than in OVX and control groups (MDA; 0.98 ± 0.04 vs. 0.82 ± 0.02 vs. 0.78 ± 0.03 nmol/mg protein, and GSH; 46.01 ± 0.91 vs. 55.21 ± 1.40 vs. 57.94 ± 0.32, respectively; p < 0.01 for both). Comparing with OVX + HFHF group, rats that received genistein, exercise and combined treatments demonstrated an improvement in liver histopathology, decreased levels of hepatic FFA (1.44 ± 0.21 vs. 0.45 ± 0.04 vs. 0.49 ± 0.05 nmol/mg protein, respectively, p < 0.01), serum IL-6 (82.80 ± 2.07 vs. 83.47 ± 2.81 vs. 94.13 ± 1.61 pg/mL, respectively, p < 0.01), and hepatic MDA (0.80 ± 0.03 vs. 0.76 ± 0.02 vs. 0.76 ± 0.03 nmol/mg protein, respectively, p < 0.01).ConclusionsGenistein and moderate intensity exercise were effective in reducing the severity of NASH in OVX rats through the reduction in liver inflammation, oxidative stress and liver fat contents.

In Vivo Antioxidant Activity of Different Fractions of Indigofera Barberi Against Paracetamol-induced Toxicity in Rats.

To evaluate the in vivo antioxidant activity of chloroform extract fractions of Indigofera barberi (whole plant) against paracetamolinduced toxicity in rats. For 7 days, rats were treated with different chloroform extract fractions and toxicity was induced with a single dose of paracetamol by intraperitoneal injection. The group of animals pretreated with 100 mg/kg p.o of fraction D of Indigofera barberi improved significantly in terms of hepatic superoxide dismutase (SOD), catalase and peroxidase activities, and glutathione levels compared to the control group. The hepatic SOD, catalase, peroxidase activities, and glutathione levels in the animal groups treated with paracetamol were 33.6±0.09 μ/mg protein, 5.5±0.23 μ/mg protein, 0.131±0.15 μ/mL, and 46.1±5.81 μM, respectively. Hepatic SOD, catalase, peroxidase, and glutathione in the fraction D treated group were 61.8±0.07 μ/mg protein, 10.6±0.16 μ/mg protein, 0.913±0.23 μ/mL, and 87.6±1.4 micro molar, respectively. Therefore, the present study revealed that fraction D of Indigofera barberi has significant in vivo antioxidant activity and can be used to protect tissue from oxidative stress. From the results, fraction D of Indigofera barberi at a dose of 100 mg/kg, p.o., improved the SOD, catalase and peroxidase activities, and glutathione levels significantly. Based on this study, we can conclude that fraction D of Indigofera barberi possesses in vivo antioxidant activity and can be employed in protecting tissue from oxidative stress.

Weaning Mice and Adult Mice Exhibit Differential Carbon Tetrachloride-Induced Acute Hepatotoxicity.

Age is a risk factor for drug-induced liver injury (DILI). However, there is a limited understanding of pediatric DILI. Here, 2-week-old weaning and 8-week-old adult male ICR mice were intraperitoneally injected with CCl4 (0.1 mmol/kg equal to 15.4 mg/kg) to comparatively evaluate the time-dependent liver damage and cellular events. CCl4 significantly enhanced the serum alanine aminotransferase/aspartate aminotransferase levels and hepatic centrilobular necrosis in the weaning mice, whereas it induced mild liver injury in the adult mice. CCl4-treated weaning mice exhibited higher hepatic levels of pro-apoptotic proteins (Bax, cleaved caspase-3, -7, and -9), activated MAPKs (p-JNK and p-Erk), and endoplasmic reticulum stress indicators (ATF6 and CHOP) and lower hepatic anti-apoptotic Bcl-2 levels than the adult mice. The weaning mice exhibited enhanced basal hepatic glutathione (GSH) levels due to high glutamate cysteine ligase (GCL) and low anti-cysteine dioxygenase (CDO) enzyme levels. However, CCl4 markedly reduced the hepatic GSH levels only in the weaning mice. Furthermore, higher hepatic levels of oxidative stress-induced malondialdehyde, 4-hydroxynonenal, nitrotyrosine-protein adducts, and oxidized proteins were observed in CCl4-treated weaning mice than in CCl4-treated adult mice. The enhanced levels of hepatic cytochrome P450 (CYP) 2E1 and CYP3A, and decreased hepatic GSH S-transferase (GST)-π and GSH reductase (GR) levels in the weaning mice may contribute to their enhanced susceptibility to liver damage.

C-reactive Protein Signaling and Chromosomal Abnormalities in Nanotoxicity Induced via Different Doses of TiO2 (80nm) Boost Liver Function.

The wide application of nanotechnology merits the need to clarify their nanotoxicity. In vivo studies have raised concerns about the toxicity of titanium dioxide nanoparticles (TiO2 NPs), but there are limited data on chromosomal abnormalities induced in hepatic tissue. In this article, the toxicity of three IP doses of TiO2 NPs (80nm) (50, 250, and 500mg/kg) through three time intervals (up to 7, 15, and 45days) on liver tissue was assessed. Hepatic catalase (CAT), glutathione (GSH), nitric oxide (NOx), and malondialdehyde (MDA) levels varied with the administered dose and exposure time of TiO2 NPs. As a result, TiO2 NPs caused a statistically significant decrease in hepatic CAT and GSH activities and a significant alleviation in MDA and NOx levels (p < 0.05), suggesting that the liver exposed to these various doses of TiO2 NPs suffered from severe oxidative stress. The extent of depletion of antioxidant enzymes and the elevation of MDA and NOx in the liver exposed to the highest dose and duration of TiO2 NPs 500mg for 45days was the greatest, suggesting that the toxicity might be dose and time dependent. Further, C-reactive protein (CRP) as an inflammatory marker was also alleviated, in addition to the apparent chromosomal aberration and liver pathologies including necrotic and fibrotic hepatocytes after exposure to 250 and 500mg/kg of TiO2 NPs for 14 and 45days that were deduced. Hence, nanotechnology-based industries are growing rapidly leading to large-scale production of engineered nanoparticles. They contribute to increased chances of human NPs exposure and health risk.

Enhancement of acetaminophen-induced chronic hepatotoxicity in spontaneously diabetic torii (SDT) rats.

Some patients encounter hepatotoxicity after repeated acetaminophen (APAP) dosing even at therapeutic doses. In the present study, we focused on the diabetic state as one of the suggested risk factors of drug-induced liver injury in humans and investigated the contribution of accelerated gluconeogenesis to the susceptibility to APAP-induced hepatotoxicity using an animal model of type 2 diabetes patients. Sprague-Dawley (SD) rats and spontaneously diabetic torii (SDT) rats were each given APAP at 0 mg/kg, 300 and 500 mg/kg for 35 days by oral gavage. Plasma and urinary glutathione-related metabolites, liver function parameters, and hepatic glutathione levels were compared between the non-APAP-treated SDT and SD rats and between the APAP-treated SDT and SD rats. Hepatic function parameters were not increased at either dose level in the APAP-treated SD rats, but were increased at both dose levels in the APAP-treated SDT rats. Increases in hepatic glutathione levels attributable to the treatment of APAP were noted only in the APAP-treated SD rats. There were differences in the profiles of plasma and urinary glutathione-related metabolites between the non-APAP-treated SD and SDT rats and the plasma/urinary endogenous metabolite profile after treatment with APAP in the SDT rats indicated that hepatic glutathione synthesis was decreased due to accelerated gluconeogenesis. In conclusion, SDT rats were more sensitive to APAP-induced chronic hepatotoxicity than SD rats and the high susceptibility of SDT rats was considered to be attributable to lowered hepatic glutathione levels induced by accelerated gluconeogenesis.

Potential Effects of Antioxidant and Serum Cholesterol‐Lowering Effects of Gynura bicolor Water Extracts in Syrian Hamster

Gynura bicolor (Roxb. and Willd.) DC (G. bicolor) is a dietary vegetable in the Far East. The aims of the present study were to investigate the antioxidant effects of the G. bicolor water extract (GBWE) and its ability to regulate the blood lipid and lipoprotein profiles. In this study, the pigment composition and antioxidant ability of the GBWE were analyzed. Syrian hamsters were fed a high‐fat diet (HFD) and the GBWE for 12 weeks, and the blood lipid levels, lipoprotein profiles, and cholesterol metabolism‐related enzyme levels were then examined. The results showed that the GBWE exhibited excellent 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical‐scavenging activity and ferrous‐ion‐chelating ability. The hepatic glutathione levels in the hamsters were increased after the administration of low (0.4 g/kg BW, GBWE‐L) or high (0.8 g/kg BW, GBWE‐H) levels of the GBWE. The GBWE‐H‐treated hamsters exhibited significantly decreased serum levels of total cholesterols (TC) and low‐density lipoprotein‐cholesterol (LDL‐C) and significantly increased levels of lectin‐cholesterol acetyltransferase (LCAT). These results showed that GBWE‐H can reduce the total cholesterol and LDL‐C levels in HFD‐fed hamsters, and this reduction might be involved in the regulation of LCAT expression.

Responsive Trimodal Probes for In Vivo Imaging of Liver Inflammation by Coassembly and GSH-Driven Disassembly

Noninvasive in vivo imaging of hepatic glutathione (GSH) levels is essential to early diagnosis and prognosis of acute hepatitis. Although GSH-responsive fluorescence imaging probes have been reported for evaluation of hepatitis conditions, the low penetration depth of light in liver tissue has impeded reliable GSH visualization in the human liver. We present a liver-targeted and GSH-responsive trimodal probe (GdNPs-Gal) for rapid evaluation of lipopolysaccharide- (LPS-) induced acute liver inflammation via noninvasive, real-time in vivo imaging of hepatic GSH depletion. GdNPs-Gal are formed by molecular coassembly of a GSH-responsive Gd(III)-based MRI probe (1-Gd) and a liver-targeted probe (1-Gal) at a mole ratio of 5/1 (1-Gd/1-Gal), which shows high r1 relaxivity with low fluorescence and fluorine magnetic resonance spectroscopic (19F-MRS) signals. Upon interaction with GSH, 1-Gd and 1-Gal are cleaved and GdNPs-Gal rapidly disassemble into small molecules 2-Gd, 2-Gal, and 3, producing a substantial decline in r1 relaxivity with compensatory enhancements in fluorescence and 19F-MRS. By combining in vivo magnetic resonance imaging (1H-MRI) with ex vivo fluorescence imaging and 19F-MRS analysis, GdNPs-Gal efficiently detect hepatic GSH using three independent modalities. We noninvasively visualized LPS-induced liver inflammation and longitudinally monitored its remediation in mice after treatment with an anti-inflammatory drug, dexamethasone (DEX). Findings highlight the potential of GdNPs-Gal for in vivo imaging of liver inflammation by integrating molecular coassembly with GSH-driven disassembly, which can be applied to other responsive molecular probes for improved in vivo imaging.

Cryptotanshinone from the Salvia miltiorrhiza Bunge Attenuates Ethanol-Induced Liver Injury by Activation of AMPK/SIRT1 and Nrf2 Signaling Pathways.

Cryptotanshinone (CT), a diterpene that is isolated from Salvia miltiorrhiza Bunge, exhibits anti-cancer, anti-oxidative, anti-fibrosis, and anti-inflammatory properties. Here, we examined whether CT administration possess a hepatoprotective effect on chronic ethanol-induced liver injury. We established a chronic alcohol feeding mouse model while using C57BL/6 mice, and examined the liver sections with hematoxylin-eosin (H&E) and Oil Red O (ORO) staining. Further, we analyzed the lipogenesis, fatty acid oxidation, oxidative stress, and inflammation genes by using quantitative polymerase chain reaction (qPCR) and immunoblotting in in vivo, and in vitro while using HepG2 and AML-12 cells. CT treatment significantly ameliorated ethanol-promoted hepatic steatosis, which was consistent with the decreased hepatic triglyceride levels. Interestingly, CT activated the phosphorylation of AMP-activated protein kinase (AMPK), sirtuin 1 (SIRT1), and nuclear factor E2-related factor 2 (Nrf2) proteins. Importantly, compound C (AMPK inhibitor) significantly blocked the CT-mediated reduction in TG accumulation, but not Ex52735 (SIRT1 inhibitor), which suggested that CT countering ethanol-promoted hepatic steatosis is mediated by AMPK activation. Furthermore, CT significantly inhibited cytochrome P450 2E1 (CYP2E1) and enhanced both the expression of antioxidant genes and hepatic glutathione levels. Finally, CT inhibited the ethanol-induced inflammation in ethanol-fed mice and HepG2 cells. Overall, CT exhibits a hepatoprotective effect against ethanol-induced liver injury by the inhibition of lipogenesis, oxidative stress, and inflammation through the activation of AMPK/SIRT1 and Nrf2 and the inhibition of CYP2E1. Therefore, CT could be an effective therapeutic agent for treating ethanol-induced liver injury.

Proteoglycan isolated from Corbicula fluminea exerts hepato-protective effects against alcohol-induced liver injury in mice

Corbicula fluminea (Asian clam), a freshwater bivalve mollusk, has been consumed in China for centuries as a health food and traditional Chinese medicine for treating liver diseases and alcoholism. This study aimed to evaluate the hepato-protective effects and potential mechanisms of a proteoglycan (PSP) from C. fluminea on alcohol-induced liver injury in mice. Results showed that PSP pretreatment significantly antagonized the increases in serum alanine aminotransferase, aspartate aminotransferase, triacylglycerides, and hepatic malondialdehyde levels; elevated the antioxidant enzyme activities and hepatic glutathione levels; and suppressed the levels of hepatic inflammatory cytokines in alcohol-induced liver injury in mice (P < 0.05). Histopathological observation further revealed the potential hepato-protective effect of PSP against alcohol damage. Particularly, PSP pretreatment resulted in significantly decreased expression of cytochrome P450 2e1 (CYP2E1) while significantly upregulating the expression of hemeoxygenase-1 (HO-1) (P < 0.05). These results suggested that PSP could protect the liver from hepatocyte injury induced by alcohol possibly by alleviating hepatic lipid metabolism, elevating antioxidant-enzyme activity, suppressing the immune inflammatory response, and reversing the expression levels of CYP2E1 and HO-1. Therefore, PSP may be developed as a food supplement that can be used to prevent liver diseases.