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At least 55 records · Page 3

A Multi-Omics Approach Demonstrates that Spaceflight Leads to Lipid Accumulation in Mouse Livers

Spaceflight has several detrimental effects on the physiology of astronauts, many of which are recapitulated in rodent models. We analyzed liver transcriptomic and proteomic data from three mouse spaceflight experiments flown aboard the International Space Station (Rodent Research-1 NASA (RR-1 NASA), Rodent Research-1 CASIS (RR-1 CASIS), Rodent Research-3 (RR-3)), and one mouse experiment flown on the Space Shuttle (Commercial Biomedical Testing Module-3 (CBTM-3) aboard STS-135). Despite the differences in genetic background and time of exposure to microgravity it was shown through Oil Red staining and histology that increased lipid accumulation was occurring in the liver of all mice flown in space compared to the ground controls. This led to further pursue the existing GeneLab datasets related to liver omics data from these mice. We were able to discover key conserved pathways across all the mice independent of the flight conditions that were related to increased lipid metabolism, fatty acid metabolism, both lipid and fatty acid processing, lipid catabolic processing, and lipid localization. In addition, key upstream regulators were predicted to be commonly regulated across all conditions which include ESR1, GCG, and NR1I2 being inhibited and INS being activated. Interestingly, estrogen receptor alpha (ESR1) expression has been known to be heavily involved with lipoprotein metabolism. In addition, insulin (INS) is the primary driver for fat metabolism and increased INS has been associated with increased fatty acids in the liver. Through additional proteomic analysis we were able to identify the majority of the key proteins related to lipids for both the RR-1 and RR-3 rodents were being up-regulated in the livers when comparing flight to ground controls. This additional confirmation of the lipid associated activity also showed that the lipid related proteins are heavily involved with lipid metabolism, cholesterol binding, and cholesterol metabolism. Lastly, the analysis also revealed that the circadian clock related pathways in the liver are commonly being increased across all space flight conditions which has also been reported in the literature to potentially cause increased liver damage. The combination of the very strong lipid uptake in the liver and the transcriptomic/proteomic signatures (including the circadian clock pathways) following spaceflight are consistent with early onset of liver disease. Taken together, these data indicate that, activation of lipotoxic pathways could persist during longer duration spaceflight which might result in the development of liver disease

Lipids↗

Spontaneous nonalcoholic fatty liver disease and ER stress in Sidt2 deficiency mice

Sidt2 is a newly discovered lysosomal membrane protein that is closely related to glucose metabolism. In the present study, we found that Sidt2 is also closely related to lipid metabolism. Gradual increases in serum triglyceride (TG) and free fatty acid, as well as elevated aspartate transaminase and alanine transaminase levels were observed in Sidt2{sup −/−} mice fed a normal diet from the age of 3 months, suggesting the presence of lipid metabolism disorders and impaired liver function in these mice. In the liver slices of 6-month-old Sidt2{sup −/−} mice, there were obvious fat degeneration and inflammatory changes. Almost all of the liver cells demonstrated different levels of lipid droplet accumulation and cell swelling, and some of the cells demonstrated balloon-like changes. Infiltration of inflammatory cells was observed in the portal area and hepatic lobule. Electron microscopy showed that macrophages tended to be attached to the endothelial cells, and a large number of lipid droplets were present in the liver cells. Oil red O staining showed that there were significantly increased number of deep straining particles in the liver cells of Sidt2{sup −/−} mice, and the TG content in liver tissue was also significantly increased. Detection of key genes and proteins related to fat synthesis showed that mRNA and protein levels of the SREBP1c in the liver of Sidt2{sup −/−} mice were significantly elevated, and the downstream genes acetyl-CoA carboxylase, fatty acid synthase, and mitochondrial glycerol 3-phosphate acyltransferase were significantly upregulated. In addition, there was severe endoplasmic reticulum stress (ERS) in the liver of Sidt2{sup −/−} mice, which had significantly increased levels of markers specific for unfolded protein response activation, Grp78 and CHOP, as well as significant elevation of downstream p-PERK, p-eIF2a, p-IRE1a, along with ER damage. These results suggest that Sidt2{sup −/−} mice had spontaneous nonalcoholic fatty liver disease (NAFLD) accompanied by ERS. In summary, as a lysosomal membrane protein, Sidt2 plays an important role in the pathogenesis of NAFLD, and ERS may mediate the occurrence and development of this disease in Sdit2 deficiency mice.

60 APPLIED LIFE SCIENCES↗

TUG1 is involved in liver fibrosis and activation of HSCs by regulating miR-29b

Highlights: • Tug1 is over-expressed in liver fibrosis and activated HSCs. • Tug1 promotes the expression of pro-fibrogenic genes in HSCs. • Tug1 regulates the expression of target genes through down-regulation of miR-29b. • Elevated TUG1 was expressed in liver cirhhosis patients. TUG1 has been shown to be involved in diverse human diseases by regulating gene expression at transcriptional and post-transcriptional levels via interaction with miRNA or proteins. However, the role of TUG1 in liver fibrosis remains unclear. Here, we found that Tug1 is dysregulated in liver fibrosis according to the microarray analysis. Moreover, we investigated the expression files of Tug1 by using CCl{sub 4}-and BDL-induced liver fibrosis model mice as well as in the primary cells isolated from the mice. We demonstrated that Tug1 is over-expressed in the fibrotic livers and activated HSCs, but not injured hepatocytes. In addition, we assessed the function of Tug1 in HSCs and found that Tug1 promotes the expression of α-SMA, Col1α1, Mmp2/9/10 and Timp1. Mechanically, Tug1 promotes the expression of these pro-fibrogenic genes by down-regulating miR-29b, thus accelerating the progression of liver fibrosis. Further study revealed that TUG1was up-regulated in liver tissues of patients with cirrhosis. All together, our data indicate that TUG1 might be a potential therapy target of liver fibrosis.

60 APPLIED LIFE SCIENCES↗

Dihydroartemisinin protects against alcoholic liver injury through alleviating hepatocyte steatosis in a farnesoid X receptor-dependent manner

Alcoholic liver disease (ALD) is a common etiology of liver diseases, characterized by hepatic steatosis. We previously identified farnesoid X receptor (FXR) as a potential therapeutic target for ALD. Dihydroartemisinin (DHA) has been recently identified to possess potent pharmacological activities on liver diseases. This study was aimed to explore the impact of DHA on ALD and further elaborate the underlying mechanisms. Gain- or loss-of-function analyses of FXR were applied in both in vivo and in vitro studies. Results demonstrated that DHA rescued FXR expression and activity in alcoholic rat livers. DHA also reduced serodiagnostic markers of liver injury, including aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and lactate dehydrogenase. DHA improved alcohol-induced liver histological lesions, expression of inflammation genes, and inflammatory cell infiltration. In addition, DHA not only attenuated hyperlipidemia but also reduced hepatic steatosis through regulating lipogenesis and lipolysis genes. In vitro experiments further consolidated the concept that DHA ameliorated ethanol-caused hepatocyte injury and steatosis. Noteworthily, DHA effects were reinforced by FXR agonist obeticholic acid or FXR expression plasmids but abrogated by FXR antagonist Z-guggulsterone or FXR siRNA. In summary, DHA significantly improved alcoholic liver injury by inhibiting hepatic steatosis, which was dependent on its activation of FXR in hepatocytes. - Highlights: • DHA rescues FXR expression in alcoholic livers. • DHA improves alcoholic liver inflammation and steatosis in a FXR-dependent way. • DHA alleviates ethanol-induced hepatocyte steatosis by activation of FXR.

60 APPLIED LIFE SCIENCES↗

Endogenous glucocorticoids exacerbate cholestasis-associated liver injury and hypercholesterolemia in mice

Cholestatic liver disease is characterized by a disruption of bile flow, bile acid toxicity, liver injury, and hypercholesterolemia. Relatively high secretion of glucocorticoids by the adrenals has been observed under cholestatic conditions. Here we investigated a contribution of the rise in endogenous glucocorticoids to initial stage cholestasis pathology. Adrenalectomized or sham-operated control C57BL/6 mice were given an oral dose of alpha-naphthylisothiocyanate to induce cholestasis. Adrenalectomy effectively lowered plasma corticosterone levels (18 ± 5 ng/ml vs 472 ± 58 ng/ml; P < 0.001) and disrupted the metabolic and anti-inflammatory glucocorticoid function. Adrenal removal did not exacerbate the cholestasis extent. In contrast, the cholestasis-associated liver injury was markedly lower in adrenalectomized mice as compared to controls as evidenced by a 84%–93% decrease in liver necrosis and plasma alanine aminotransferase and bile acid levels (P < 0.001 for all). Gene expression analysis on livers from adrenalectomized mice suggested the absence of bile acid toxicity-associated farnesoid X receptor signaling in the context of a 44% (P < 0.01) and 82% (P < 0.001) reduction in sodium/bile acid cotransporter member 1 transcript level as compared to respectively control and non-diseased mice. Adrenalectomy reduced the expression of the cholesterol synthesis gene HMG-CoA reductase by 70% (P < 0.05), which translated into a 73% lower plasma total cholesterol level (P < 0.05). Treatment of C57BL/6 mice with the glucocorticoid receptor antagonist RU-486 recapitulated the protective effect of adrenalectomy on indices of liver injury and hypercholesterolemia. In conclusion, we have shown that endogenous glucocorticoids exacerbate the liver injury and hypercholesterolemia associated with acute cholestasis in mice. - Highlights: • Cholestasis is associated with increased plasma glucocorticoid levels in mice. • Adrenalectomy lowers cholestasis-associated liver injury and hypercholesterolemia. • GR antagonist RU-486 similarly improves the cholestasis phenotype. • Endogenous glucocorticoids promote re-uptake of circulating bile acids into liver.

60 APPLIED LIFE SCIENCES↗

Role of dietary fatty acids in liver injury caused by vinyl chloride metabolites in mice

Background: Vinyl chloride (VC) causes toxicant-associated steatohepatitis at high exposure levels. Recent work by this group suggests that underlying liver disease may predispose the liver to VC hepatotoxicity at lower exposure levels. The most common form of underlying liver disease in the developed world is non-alcoholic fatty liver disease (NAFLD). It is well-known that the type of dietary fat can play an important role in the pathogenesis of NAFLD. However, whether the combination of dietary fat and VC/metabolites promotes liver injury has not been studied. Methods: Mice were administered chloroethanol (CE - a VC metabolite) or vehicle once, 10 weeks after being fed diets rich in saturated fatty acids (HSFA), rich in poly-unsaturated fatty acids (HPUFA), or the respective low-fat control diets (LSFA; LPUFA). Results: In control mice, chloroethanol caused no detectable liver injury, as determined by plasma transaminases and histologic indices of damage. In HSFA-fed mice, chloroethanol increased HSFA-induced liver damage, steatosis, infiltrating inflammatory cells, hepatic expression of proinflammatory cytokines, and markers of endoplasmic reticulum (ER) stress. Moreover, markers of inflammasome activation were increased, while markers of inflammasome inhibition were downregulated. In mice fed HPUFA all of these effects were significantly attenuated. Conclusions: Chloroethanol promotes inflammatory liver injury caused by dietary fatty acids. This effect is far more exacerbated with saturated fat, versus poly-unsaturated fat; and strongly correlates with a robust activation of the NLRP3 inflammasome in the saturated fed animals only. Taken together these data support the hypothesis that environmental toxicant exposure can exacerbate the severity of NAFLD/NASH. - Highlights: • CE promotes inflammatory liver injury caused by dietary fatty acids. • This effect is stronger with saturated than with unsaturated fatty acids. • Damage caused by saturated fat and CE correlates with inflammasome activation.

60 APPLIED LIFE SCIENCES↗

Fast automatic 3D liver segmentation based on a three-level AdaBoost-guided active shape model

Purpose: A robust, automatic, and rapid method for liver delineation is urgently needed for the diagnosis and treatment of liver disorders. Until now, the high variability in liver shape, local image artifacts, and the presence of tumors have complicated the development of automatic 3D liver segmentation. In this study, an automatic three-level AdaBoost-guided active shape model (ASM) is proposed for the segmentation of the liver based on enhanced computed tomography images in a robust and fast manner, with an emphasis on the detection of tumors. Methods: The AdaBoost voxel classifier and AdaBoost profile classifier were used to automatically guide three-level active shape modeling. In the first level of model initialization, fast automatic liver segmentation by an AdaBoost voxel classifier method is proposed. A shape model is then initialized by registration with the resulting rough segmentation. In the second level of active shape model fitting, a prior model based on the two-class AdaBoost profile classifier is proposed to identify the optimal surface. In the third level, a deformable simplex mesh with profile probability and curvature constraint as the external force is used to refine the shape fitting result. In total, three registration methods—3D similarity registration, probability atlas B-spline, and their proposed deformable closest point registration—are used to establish shape correspondence. Results: The proposed method was evaluated using three public challenge datasets: 3Dircadb1, SLIVER07, and Visceral Anatomy3. The results showed that our approach performs with promising efficiency, with an average of 35 s, and accuracy, with an average Dice similarity coefficient (DSC) of 0.94 ± 0.02, 0.96 ± 0.01, and 0.94 ± 0.02 for the 3Dircadb1, SLIVER07, and Anatomy3 training datasets, respectively. The DSC of the SLIVER07 testing and Anatomy3 unseen testing datasets were 0.964 and 0.933, respectively. Conclusions: The proposed automatic approach achieves robust, accurate, and fast liver segmentation for 3D CTce datasets. The AdaBoost voxel classifier can detect liver area quickly without errors and provides sufficient liver shape information for model initialization. The AdaBoost profile classifier achieves sufficient accuracy and greatly decreases segmentation time. These results show that the proposed segmentation method achieves a level of accuracy comparable to that of state-of-the-art automatic methods based on ASM.

60 APPLIED LIFE SCIENCES↗

Sex and age differences in the expression of liver microRNAs during the life span of F344 rats

Background: Physiological factors such as age and sex have been shown to be risk factors for adverse effects in the liver, including liver diseases and drug-induced liver injury. Previously, we have reported age- and sex-related significant differences in hepatic basal gene expression in rats during the life span that may be related to susceptibility to such adverse effects. However, the underlying mechanisms of the gene expression changes were not fully understood. In recent years, increasing evidence for epigenetic mechanisms of gene regulation has fueled interest in the role of microRNAs (miRNAs) in toxicogenomics and biomarker discovery. We therefore proposed that significant age and sex differences exist in baseline liver miRNA expression, and that comprehensive profiling of miRNAs will provide insights into the epigenetic regulation of gene expression in rat liver. Methods: To address this, liver tissues from male and female F344 rats were examined at 2, 5, 6, 8, 15, 21, 52, 78, and 104 weeks of age for the expression of 677 unique miRNAs. Following data processing, predictive pathway analysis was performed on selected miRNAs that exhibited prominent age and/or sex differences in expression. Results: Of the 314 miRNAs found to be expressed, 214 were differentially expressed; 65 and 212 miRNAs showed significant (false discovery rate (FDR) <5% and ≥1.5-fold change) sex- and age-related differences in expression, respectively. Thirty-eight miRNAs showed 2-week-specific expression, of which 31 miRNAs were found to be encoded within the Dlk1-Dio3 cluster located on chromosome 6. This cluster has been associated with tissue proliferation and differentiation, and liver energy homeostasis in postnatal development. Predictive pathway analysis linked sex-biased miRNA expression with sexually dimorphic molecular functions and toxicological functions that may reflect sex differences in hepatic physiology and disease. The expression of miRNAs (miR-18a, miR-99a, and miR-203, miR-451) was also found to associate with specific sexually dimorphic hepatic histopathology. The expression of miRNAs involved in regulating cell death, cell proliferation, and cell cycle was found to change as the rats matured from adult to old age. Conclusions: Overall, significant age- and sex-related differences in liver miRNA expression were identified and linked to histopathological findings and predicted functional pathways that may underlie susceptibilities to liver toxicity and disease.

59 BASIC BIOLOGICAL SCIENCES↗

Mechanical Response of Porcine Liver Tissue under High Strain Rate Compression

In automobile accidents, abdominal injuries are often life-threatening yet not apparent at the time of initial injury. The liver is the most commonly injured abdominal organ from this type of trauma. In contrast to current safety tests involving crash dummies, a more detailed, efficient approach to predict the risk of human injuries is computational modelling and simulations. Further, the development of accurate computational human models requires knowledge of the mechanical properties of tissues in various stress states, especially in high-impact scenarios. In this study, a polymeric split-Hopkinson pressure bar (PSHPB) was utilized to apply various high strain rates to porcine liver tissue to investigate its material behavior during high strain rate compression. Liver tissues were subjected to high strain rate impacts at 350, 550, 1000, and 1550 s –1 . Tissue directional dependency was also explored by PSHPB testing along three orthogonal directions of liver at a strain rate of 350 s –1 . Histology of samples from each of the three directions was performed to examine the structural properties of porcine liver. Porcine liver tissue showed an inelastic and strain rate-sensitive response at high strain rates. The liver tissue was found lacking directional dependency, which could be explained by the isotropic microstructure observed after staining and imaging. Furthermore, finite element analysis (FEA) of the PSHPB tests revealed the stress profile inside liver tissue and served as a validation of PSHPB methodology. The present findings can assist in the development of more accurate computational models of liver tissue at high-rate impact conditions allowing for understanding of subfailure and failure mechanisms.

60 APPLIED LIFE SCIENCES↗

Obeticholic acid protects against carbon tetrachloride-induced acute liver injury and inflammation

The farnesoid X receptor (FXR) is a ligand-activated transcription factor that plays important roles in regulating bile acid homeostasis. The aim of the present study was to investigate the effects of obeticholic acid (OCA), a novel synthetic FXR agonist, carbon tetrachloride (CCl{sub 4})-induced acute liver injury. Mice were intraperitoneally injected with CCl{sub 4} (0.15 ml/kg). In CCl{sub 4} + OCA group, mice were orally with OCA (5 mg/kg) 48, 24 and 1 h before CCl{sub 4}. As expected, hepatic FXR was activated by OCA. Interestingly, OCA pretreatment alleviated CCl{sub 4}-induced elevation of serum ALT and hepatic necrosis. Moreover, OCA pretreatment inhibited CCl{sub 4}-induced hepatocyte apoptosis. Additional experiment showed that OCA inhibits CCl{sub 4}-induced hepatic chemokine gene Mcp-1, Mip-2 and Kc. Moreover, OCA inhibits CCl{sub 4}-induced hepatic pro-inflammatory gene Tnf-α and Il-1β. By contrast, OCA pretreatment elevated hepatic anti-inflammatory gene Il-4. Further analysis showed that OCA pretreatment inhibited hepatic IκB phosphorylation and blocked nuclear translocation of NF-κB p65 and p50 subunits during CCl{sub 4}-induced acute liver injury. In addition, OCA pretreatment inhibited hepatic Akt, ERK and p38 phosphorylation in CCl{sub 4}-induced acute liver injury. These results suggest that OCA protects against CCl{sub 4}-induced acute liver injury and inflammation. Synthetic FXR agonists may be effective antidotes for hepatic inflammation during acute liver injury. - Highlights: • OCA pretreatment activates hepatic FXR. • FXR activation protects against CCl{sub 4}-induced acute liver injury. • FXR activation inhibits hepatocyte apoptosis during CCl{sub 4}-induced liver injury. • FXR activation differentially regulates hepatic inflammatory genes. • Synthetic FXR agonists are effective antidotes for acute liver injury.

60 APPLIED LIFE SCIENCES↗

Can MR elastography be used to measure liver stiffness in patients with iron overload?

Untreated hepatic iron overload causes hepatic fibrosis and cirrhosis and can predispose to hepatocellular carcinoma. MR elastography (MRE) provides a non-invasive means to measure liver stiffness, which correlates with liver fibrosis but standard gradient recalled echo (GRE)-based MRE techniques fail in patients with high iron due to very low hepatic signal. Short echo time (TE) 2D spin echo echoplanar imaging (SE-EPI)-based MRE may allow measurement of stiffness in the iron loaded liver. The purpose of this study was to describe the use of such an MRE sequence in patients undergoing liver iron quantification by MRI. In our preliminary study of 43 patients with mean LIC of 9.3 mg/g (range 1.8–21.5 mg/g), liver stiffness measurements could be made in 77% (33/43) of patients with a short TE, SE-EPI based MRE sequence. On average, mean LIC in patients with failed MRE was higher than in those with successful MRE (15.9 mg/g dry weight vs. 7.3 mg/g), but a cut-off value for successful MRE could not be established. Seven patients (21% of those with successful MRE) had liver stiffness values suggestive of the presence of significant fibrosis (> 2.49 kPa). A short TE, SE-EPI based MR elastography sequence allows successful measurement of liver stiffness in a majority of patients with liver iron loading, potentially allowing non-invasive screening for fibrosis.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Magnetic resonance elastography SE-EPI vs GRE sequences at 3T in a pediatric population with liver disease

Purpose: The goal of our study is to compare hepatic stiffness measures using gradient-recalled echo (GRE) versus spin-echo echo planar imaging (SE-EPI)-based MR Elastography (MRE) at 3T used to measure hepatic stiffness in a patients with suspected liver diseases. Materials and methods: This retrospective study included 52 patients with liver disease who underwent a 3T MRE exam including both an investigational SE-EPI-based technique and a product GRE-based technique. Regions of interest (ROI) were placed on the elastograms to measure elastography-derived liver stiffness as well as the area included within the ROIs. The mean liver stiffness values and area of ROIs were compared. Results: The mean liver stiffness was 3.72 kilopascal (kPa) ± 1.29 using GRE MRE and 3.78 kPa ± 1.13 using SE-EPI MRE. Measurement of liver stiffness showed excellent agreement between the two pulse sequences with a mean bias of − 0.1 kPa (range − 1.8 to 1.7 kPa) between sequences. The mean measurable ROI area was higher with SE-EPI (313.8 cm{sup 2} ± 213.8) than with the GRE technique (208.6 cm{sup 2} ± 114.8), and the difference was statistically significant (P < 0.05). Conclusions: Our data shows excellent agreement of measured liver stiffness between GRE and SE-EPI-based sequences at 3T. Our results show the advantage of a SE-EPI MRE sequence in terms of image quality, ROI size and acquisition time with equivalent liver stiffness measurements as compared to GRE-MRE sequence.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Agkihpin, a novel SVAE may inhibit the migration and invasion of liver cancer cells associated with the inversion of EMT induced by Wnt/β-catenin signaling inhibition

In our previous work, agkihpin, a snake venom arginine esterase (SVAE), was isolated from the Gloydius halys Pallas, which could attenuate the migration of liver cancer cells. However, the mechanism of the effect of agkihpin on attenuating migration of liver cancer cell is unknown yet. Here, to learn more about agkihpin and explore the possibility of agkihpin as an anti-metastatic drug in the future, a series of experiments about the migration and invasion of liver cancer cells with agkihpin, HepG 2 and SMMC-7721, was conducted. Epithelial-mesenchymal transition (EMT) is an initial step and a major phenotype of cancer metastasis and invasion, while a number of EMT opposite phenomenons were observed, for example, epithelial marker E-cadherin was up-regulated, mesenchymal markers N-cadherin and Vimentin, and transcription regulators Snail and twist were down-regulated after treating with agkihpin in liver cancer cells; canonical Wnt/β-catenin pathway, one of the signals initiated EMT, was inhibited by decreased expressions of FZD7 and β-catenin, phosphorylation of GSK3β (Ser9), and nuclear β-catenin accumulation in agkihpin treated cancer cells. By using bioinformatics analysis and protease activity analysis in vitro we also found that agkihpin might bind and degrade FZD7. As a result, we hypothesized that agkihpin could inhibit the Wnt/β-catenin signaling pathway by cleaving FZD7, leading to the inactivation of the TCF/LEF transcription factor, which contributed to the inversion of EMT, and finally attenuated the migration and invasion of liver cancer cells. Therefore, our findings provided novel mechanistic insights into the role of SVAEs in liver cancer controlling, and raised the possibility that agkihpin may be used therapeutically in liver cancer. - Highlights: • We found for the first time that SVAE may inhibit the migration and invasion of liver cancer cells. • The inhibition of migration and invasion was associated with the inversion of EMT. • The inversion of EMT was induced by Wnt/β-catenin signaling inhibition.

60 APPLIED LIFE SCIENCES↗

Molecular evidence of offspring liver dysfunction after maternal exposure to zinc oxide nanoparticles

Recently, reproductive, embryonic and developmental toxicity have been considered as one important sector of nanoparticle (NP) toxicology, with some studies already suggesting varying levels of toxicity and possible transgenerational toxic effects. Even though many studies have investigated the toxic effects of zinc oxide nanoparticles (ZnO NPs), little is known of their impact on overall reproductive outcome and transgenerational effects. Previously we found ZnO NPs caused liver dysfunction in lipid synthesis. This investigation, for the first time, explored the liver dysfunction at the molecular level of gene and protein expression in offspring after maternal exposure to ZnO NPs. Three pathways were investigated: lipid synthesis, growth related factors and cell toxic biomarkers/apoptosis at 5 different time points from embryonic day-18 to postnatal day-20. It was found that the expression of 15, 16, and 16 genes in lipid synthesis, growth related factors and cell toxic biomarkers/apoptosis signalling pathway respectively in F1 animal liver were altered by ZnO NPs compared to ZnSO{sub 4}. The proteins in these signalling pathways (five in each pathways analyzed) in F1 animal liver were also changed by ZnO NPs compared to ZnSO{sub 4}. The results suggest that ZnO NPs caused maternal liver defects can also be detected in offspring that might result in problems on offspring liver development, mainly on lipid synthesis, growth, and lesions or apoptosis. Along with others, this study suggests that ZnO NPs may pose reproductive, embryonic and developmental toxicity; therefore, precautions should be taken with regard to human exposure during daily life. - Highlights: • Oral ZnO NPs exposure caused abnormal gene and protein expression in offspring liver. • Oral ZnO NPs exposure could induce inheritance impacts on liver development. • Oral ZnO NPs exposure could be considered as developmental hazardous material.

60 APPLIED LIFE SCIENCES↗

NLRP3 inflammasome activation in liver cirrhotic patients

Highlights: • Plasma IL-1β levels were higher in plasma in patients with liver cirrhosis than control. • Plasma IL-18 levels were higher in plasma in patients with liver cirrhosis than control. • Plasma IL-18 were significantly positively associated with Child-Pugh classification. • NLRP3 expression were increased in the livers of patients with cirrhosis. NLRP3 inflammasome activation is involved in the mechanism of liver cirrhosis. In this study, we investigated the levels of plasma IL-1β and IL-18 and their relationship to component traits in patients with liver cirrhosis, and NLRP3 inflammasome expression in liver of patients with liver cirrhosis.

60 APPLIED LIFE SCIENCES↗

Cytokines and {sup 90}Y-Radioembolization: Relation to Liver Function and Overall Survival

BackgroundTo evaluate the course of pro- and anti-inflammatory cytokines after {sup 90}Y-radioembolization (RE) of liver malignancies and to identify prognosticators for liver-related adverse events and survival.MethodsIn 34 consecutive patients with secondary or primary liver tumors scheduled for RE, the following cytokines were measured prior to and 2 h, 3 days, and 6 weeks after RE: interleukin (IL) -1, IL-2, IL-4, IL-6, IL-8, tumor necrosis factor alpha (TNF-α), and interferon-γ. Liver function impairment was defined as an elevation of liver-related laboratory values as graded by CTCAE ≥ 2 and/or serum bilirubin ≥30 µmol/l and/or development of ascites at 6-week follow-up.ResultsSignificant changes over time were seen in IL-1 (increase from 0.4 pg/ml (±0.7) at baseline to 1.1 pg/ml (±1.4) 3 days after RE (p = 0.02)), and in IL-6 (increase from 16.8 pg/ml (±21.8) at baseline to 54.6 pg/ml (±78.2) 3 days after RE (p = 0.003)). Baseline values of IL-6 and IL-8 were independently associated with liver function impairment at follow-up as well as decreased survival with an optimal cutoff at 6.53 and 60.8 pg/ml, respectively.ConclusionExpected changes in pro- and anti-inflammatory cytokines after RE were shown. Furthermore, baseline values of IL-6 and IL-8 were associated with later liver dysfunction and survival. We hypothesize that these biomarkers are potential prognosticators and might help in patient selection for RE.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

FXR blocks the growth of liver cancer cells through inhibiting mTOR-s6K pathway

The nuclear receptor Farnesoid X Receptor (FXR) is likely a tumor suppressor in liver tissue but its molecular mechanism of suppression is not well understood. In this study, the gene expression profile of human liver cancer cells was investigated by microarray. Bioinformatics analysis of these data revealed that FXR might regulate the mTOR/S6K signaling pathway. This was confirmed by altering the expression level of FXR in liver cancer cells. Overexpression of FXR prevented the growth of cells and induced cell cycle arrest, which was enhanced by the mTOR/S6K inhibitor rapamycin. FXR upregulation also intensified the inhibition of cell growth by rapamycin. Downregulation of FXR produced the opposite effect. Finally, we found that ectopic expression of FXR in SK-Hep-1 xenografts inhibits tumor growth and reduces expression of the phosphorylated protein S6K. Taken together, our data provide the first evidence that FXR suppresses proliferation of human liver cancer cells via the inhibition of the mTOR/S6K signaling pathway. FXR expression can be used as a biomarker of personalized mTOR inhibitor treatment assessment for liver cancer patients. -- Highlights: •FXR inhibits the proliferation of liver cancer cells by prolonging G0/G1 phase. •Microarray results indicate that mTOR-S6k signaling is involved in cellular processes in which FXR plays an important role. •FXR blocks the growth of liver cancer cells via the inhibition of the mTOR/S6K signaling pathway in vitro and in vivo.

60 APPLIED LIFE SCIENCES↗

Berberine protects against ischemia/reperfusion injury after orthotopic liver transplantation via activating Sirt1/FoxO3α induced autophagy

The effects and mechanism of berberine (BBR) on hepatic injury after orthotopic liver transplantation (OLT) have not been well characterized. We examined the role of Sirt1/FoxO3α axis in the protective effect of BBR on ischemia/reperfusion injury after OLT. Adult male Wistar rats were randomly allocated into four groups: Sham, OLT, OLT with BBR pretreatment (BBR), OLT with BBR and Sirt1 inhibitor (EX527) pretreatment group (EX527). The liver function and oxidative stress level were measured by biochemical and histopathologic examinations. The formation of autophagosome was observed by transmission electron microscopy. The apoptotic rate was determined by TUNEL analysis and the apoptotic mRNA expression. The expression of Sirt1, FoxO3α, Beclin-1, LC3-II/LC3-I, p62 and the acetylation of FoxO3α were assayed by western blot assay and immunoprecipitation. Compared with the OLT group, BBR dramatically attenuated the histopathologic damage, restored the liver function, and decreased the oxidative stress level. Simultaneously, BBR significantly ameliorated apoptosis by decreasing the apoptotic rate and the expression of apoptotic mRNA in rats subjected to OLT. The level of Beclin-1 and LC3-II/LC3-I were upregulated with the inhibition of p62. The deacetylation of FoxO3α by Sirt1 was enhanced in the nuclear of liver after pretreated with BBR. However, the inhibition of Sirt1 by EX527 counteracted the protective effects of BBR. Thus, BBR preconditioning promotes liver transplant ischemia/reperfusion injury partly via activating Sirt1/FoxO3α mediated autophagy. - Highlights: • Berberine alleviated the histopathologic and functional damage of transplant liver. • Liver transplantation inhibited the acetylation and activation of FoxO3α which was responsible for motivating the autophagic machinery. • Berberine pretreatment reduced apoptotic cell death by enhancing Sirt1/FoxO3α induced autophagy.

60 APPLIED LIFE SCIENCES↗