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Sample records for mediated liver regeneration

  1. Liver regeneration

    NARCIS (Netherlands)

    Chamuleau, R. A.; Bosman, D. K.

    1988-01-01

    Despite great advances in analysing hemodynamic, morphological and biochemical changes during the process of liver regeneration, the exact (patho)physiological mechanism is still unknown. A short survey of literature is given of the kinetics of liver regeneration and the significance of different

  2. Two sides of one coin: massive hepatic necrosis and progenitor cell-mediated regeneration in acute liver failure

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    Honglei eWeng

    2015-06-01

    Full Text Available Massive hepatic necrosis is a key event underlying acute liver failure, a serious clinical syndrome with high mortality. Massive hepatic necrosis in acute liver failure has unique pathophysiological characteristics including extremely rapid parenchymal cell death and removal. On the other hand, massive necrosis rapidly induces the activation of liver progenitor cells, the so-called second pathway of liver regeneration. The final clinical outcome of acute liver failure depends on whether liver progenitor cell-mediated regeneration can efficiently restore parenchymal mass and function within a short time. This review summarizes the current knowledge regarding massive hepatic necrosis and liver progenitor cell-mediated regeneration in patients with acute liver failure, the two sides of one coin.

  3. Two sides of one coin: massive hepatic necrosis and progenitor cell-mediated regeneration in acute liver failure.

    Science.gov (United States)

    Weng, Hong-Lei; Cai, Xiaobo; Yuan, Xiaodong; Liebe, Roman; Dooley, Steven; Li, Hai; Wang, Tai-Ling

    2015-01-01

    Massive hepatic necrosis is a key event underlying acute liver failure, a serious clinical syndrome with high mortality. Massive hepatic necrosis in acute liver failure has unique pathophysiological characteristics including extremely rapid parenchymal cell death and removal. On the other hand, massive necrosis rapidly induces the activation of liver progenitor cells, the so-called "second pathway of liver regeneration." The final clinical outcome of acute liver failure depends on whether liver progenitor cell-mediated regeneration can efficiently restore parenchymal mass and function within a short time. This review summarizes the current knowledge regarding massive hepatic necrosis and liver progenitor cell-mediated regeneration in patients with acute liver failure, the two sides of one coin.

  4. Remarkable heterogeneity displayed by oval cells in rat and mouse models of stem cell-mediated liver regeneration

    DEFF Research Database (Denmark)

    Jelnes, Peter; Santoni-Rugiu, Eric; Rasmussen, Morten

    2007-01-01

    The experimental protocols used in the investigation of stem cell-mediated liver regeneration in rodents are characterized by activation of the hepatic stem cell compartment in the canals of Hering followed by transit amplification of oval cells and their subsequent differentiation along hepatic...... the molecular phenotypes of oval cells in several of the most commonly used protocols of stem cell-mediated liver regeneration-namely, treatment with 2-acetylaminofluorene and partial (70%) hepatectomy (AAF/PHx); a choline-deficient, ethionine-supplemented (CDE) diet; a 3,5-diethoxycarbonyl-1,4-dihydro...... remarkable phenotypic discrepancies exhibited by oval cells in stem cell-mediated liver regeneration between rats and mice and underline the importance of careful extrapolation between individual species....

  5. Platelets prime hematopoietic and vascular niche to drive angiocrine-mediated liver regeneration.

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    Shido, Koji; Chavez, Deebly; Cao, Zhongwei; Ko, Jane; Rafii, Shahin; Ding, Bi-Sen

    2017-01-01

    In mammals, the livers regenerate after chemical injury or resection of hepatic lobe by hepatectomy. How liver regeneration is initiated after mass loss remains to be defined. Here, we report that following liver injury, activated platelets deploy SDF-1 and VEGF-A to stimulate CXCR7 + liver sinusoidal endothelial cell (LSEC) and VEGFR1 + myeloid cell, orchestrating hepatic regeneration. After carbon tetrachloride (CCl 4 ) injection or hepatectomy, platelets and CD11b + VEGFR1 + myeloid cells were recruited LSEC, and liver regeneration in both models was impaired in thrombopoietin-deficient ( Thpo -/- ) mice lacking circulating platelets. This impeded regeneration phenotype was recapitulated in mice with either conditional ablation of Cxcr7 in LSEC ( Cxcr7 iΔ/iΔ ) or Vegfr1 in myeloid cell ( Vegfr1 lysM/lysM ). Both Vegfr1 lysM/lysM and Cxcr7 iΔ/iΔ mice exhibited suppressed expression of hepatocyte growth factor and Wnt2, two crucial trophogenic angiocrine factors instigating hepatocyte propagation. Of note, administration of recombinant thrombopoietin restored the prohibited liver regeneration in the tested genetic models. As such, our data suggest that platelets and myeloid cells jointly activate the vascular niche to produce pro-regenerative endothelial paracrine/angiocrine factors. Modulating this "hematopoietic-vascular niche" might help to develop regenerative therapy strategy for hepatic disorders.

  6. Platelets prime hematopoietic–vascular niche to drive angiocrine-mediated liver regeneration

    Science.gov (United States)

    Shido, Koji; Chavez, Deebly; Cao, Zhongwei; Ko, Jane L; Rafii, Shahin; Ding, Bi-Sen

    2017-01-01

    In mammals, the livers regenerate after chemical injury or resection of hepatic lobe by hepatectomy. How liver regeneration is initiated after mass loss remains to be defined. Here we report that following liver injury, activated platelets deploy SDF-1 and VEGF-A to stimulate CXCR7+ liver sinusoidal endothelial cell (LSEC) and VEGFR1+ myeloid cell, orchestrating hepatic regeneration. After carbon tetrachloride injection or hepatectomy, platelets and CD11b+VEGFR1+ myeloid cells were recruited to LSECs, and liver regeneration in both models was impaired in thrombopoietin-deficient (Thpo−/−) mice repressing production of circulating platelets. This impeded regeneration phenotype was recapitulated in mice with either conditional ablation of Cxcr7 in LSEC (Cxcr7iΔ/iΔ) or Vegfr1 in myeloid cell (Vegfr1lysM/lysM). Both Vegfr1lysM/lysM and Cxcr7iΔ/iΔ mice exhibited suppressed expression of hepatocyte growth factor and Wnt2, two crucial trophogenic angiocrine factors instigating hepatocyte propagation. Of note, administration of recombinant thrombopoietin restored the prohibited liver regeneration in the tested genetic models. As such, our data suggest that platelets and myeloid cells jointly activate the vascular niche to produce pro-regenerative endothelial paracrine/angiocrine factors. Modulating this ‘hematopoietic–vascular niche’ might help to develop regenerative therapy strategy for hepatic disorders. PMID:29201496

  7. Hedgehog pathway mediates early acceleration of liver regeneration induced by a novel two-staged hepatectomy in mice.

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    Langiewicz, Magda; Schlegel, Andrea; Saponara, Enrica; Linecker, Michael; Borger, Pieter; Graf, Rolf; Humar, Bostjan; Clavien, Pierre A

    2017-03-01

    ALPPS, a novel two-staged approach for the surgical removal of large/multiple liver tumors, combines portal vein ligation (PVL) with parenchymal transection. This causes acceleration of compensatory liver growth, enabling faster and more extensive tumor removal. We sought to identify the plasma factors thought to mediate the regenerative acceleration following ALPPS. We compared a mouse model of ALPPS against PVL and additional control surgeries (n=6 per group). RNA deep sequencing was performed to identify candidate molecules unique to ALPPS liver (n=3 per group). Recombinant protein and a neutralizing antibody combined with appropriate surgeries were used to explore candidate functions in ALPPS (n=6 per group). Indian hedgehog (IHH/Ihh) levels were assessed in human ALPPS patient plasma (n=6). ALPPS in mouse confirmed significant acceleration of liver regeneration relative to PVL (pIhh mRNA, coding for a secreted ligand inducing hedgehog signaling, was uniquely upregulated in ALPPS liver (pIhh plasma levels rose 4h after surgery (pIhh alone was sufficient to induce ALPPS-like acceleration of liver growth. Conversely, blocking Ihh markedly inhibited the accelerating effects of ALPPS. In the small cohort of ALPPS patients, IHH tended to be elevated early after surgery. Ihh and hedgehog pathway activation provide the first mechanistic insight into the acceleration of liver regeneration triggered by ALPPS surgery. The accelerating potency of recombinant Ihh, and its potential effect in human ALPPS may lead to a clinical role for this protein. ALPPS, a novel two-staged hepatectomy, accelerates liver regeneration, thereby helping to treat patients with otherwise unresectable liver tumors. The molecular mechanisms behind this accelerated regeneration are unknown. Here, we elucidate that Indian hedgehog, a secreted ligand important for fetal development, is a crucial mediator of the regenerative acceleration triggered by ALPPS surgery. Copyright © 2016. Published by

  8. Med1 subunit of the mediator complex in nuclear receptor-regulated energy metabolism, liver regeneration, and hepatocarcinogenesis.

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    Jia, Yuzhi; Viswakarma, Navin; Reddy, Janardan K

    2014-01-01

    Several nuclear receptors regulate diverse metabolic functions that impact on critical biological processes, such as development, differentiation, cellular regeneration, and neoplastic conversion. In the liver, some members of the nuclear receptor family, such as peroxisome proliferator-activated receptors (PPARs), constitutive androstane receptor (CAR), farnesoid X receptor (FXR), liver X receptor (LXR), pregnane X receptor (PXR), glucocorticoid receptor (GR), and others, regulate energy homeostasis, the formation and excretion of bile acids, and detoxification of xenobiotics. Excess energy burning resulting from increases in fatty acid oxidation systems in liver generates reactive oxygen species, and the resulting oxidative damage influences liver regeneration and liver tumor development. These nuclear receptors are important sensors of exogenous activators as well as receptor-specific endogenous ligands. In this regard, gene knockout mouse models revealed that some lipid-metabolizing enzymes generate PPARα-activating ligands, while others such as ACOX1 (fatty acyl-CoA oxidase1) inactivate these endogenous PPARα activators. In the absence of ACOX1, the unmetabolized ACOX1 substrates cause sustained activation of PPARα, and the resulting increase in energy burning leads to hepatocarcinogenesis. Ligand-activated nuclear receptors recruit the multisubunit Mediator complex for RNA polymerase II-dependent gene transcription. Evidence indicates that the Med1 subunit of the Mediator is essential for PPARα, PPARγ, CAR, and GR signaling in liver. Med1 null hepatocytes fail to respond to PPARα activators in that these cells do not show induction of peroxisome proliferation and increases in fatty acid oxidation enzymes. Med1-deficient hepatocytes show no increase in cell proliferation and do not give rise to liver tumors. Identification of nuclear receptor-specific coactivators and Mediator subunits should further our understanding of the complexities of metabolic

  9. Enhancement of liver regeneration and liver surgery

    NARCIS (Netherlands)

    Olthof, P.B.

    2017-01-01

    Liver regeneration allows surgical resection of up to 75% of the liver and enables curative treatment potential for patients with primary or secondary hepatic malignancies. Liver surgery is associated with substantial risks, reflected by considerable morbidity and mortality rates. Optimization of

  10. Role of liver progenitors in liver regeneration.

    Science.gov (United States)

    Best, Jan; Manka, Paul; Syn, Wing-Kin; Dollé, Laurent; van Grunsven, Leo A; Canbay, Ali

    2015-02-01

    During massive liver injury and hepatocyte loss, the intrinsic regenerative capacity of the liver by replication of resident hepatocytes is overwhelmed. Treatment of this condition depends on the cause of liver injury, though in many cases liver transplantation (LT) remains the only curative option. LT for end stage chronic and acute liver diseases is hampered by shortage of donor organs and requires immunosuppression. Hepatocyte transplantation is limited by yet unresolved technical difficulties. Since currently no treatment is available to facilitate liver regeneration directly, therapies involving the use of resident liver stem or progenitor cells (LPCs) or non-liver stem cells are coming to fore. LPCs are quiescent in the healthy liver, but may be activated under conditions where the regenerative capacity of mature hepatocytes is severely impaired. Non-liver stem cells include embryonic stem cells (ES cells) and mesenchymal stem cells (MSCs). In the first section, we aim to provide an overview of the role of putative cytokines, growth factors, mitogens and hormones in regulating LPC response and briefly discuss the prognostic value of the LPC response in clinical practice. In the latter section, we will highlight the role of other (non-liver) stem cells in transplantation and discuss advantages and disadvantages of ES cells, induced pluripotent stem cells (iPS), as well as MSCs.

  11. Serial analysis of gene expression (SAGE) in rat liver regeneration

    International Nuclear Information System (INIS)

    Cimica, Velasco; Batusic, Danko; Haralanova-Ilieva, Borislava; Chen, Yonglong; Hollemann, Thomas; Pieler, Tomas; Ramadori, Giuliano

    2007-01-01

    We have applied serial analysis of gene expression for studying the molecular mechanism of the rat liver regeneration in the model of 70% partial hepatectomy. We generated three SAGE libraries from a normal control liver (NL library: 52,343 tags), from a sham control operated liver (Sham library: 51,028 tags), and from a regenerating liver (PH library: 53,061 tags). By SAGE bioinformatics analysis we identified 40 induced genes and 20 repressed genes during the liver regeneration. We verified temporal expression of such genes by real time PCR during the regeneration process and we characterized 13 induced genes and 3 repressed genes. We found connective tissue growth factor transcript and protein induced very early at 4 h after PH operation before hepatocytes proliferation is triggered. Our study suggests CTGF as a growth factor signaling mediator that could be involved directly in the mechanism of liver regeneration induction

  12. Liver Development, Regeneration, and Carcinogenesis

    Directory of Open Access Journals (Sweden)

    Janet W. C. Kung

    2010-01-01

    Full Text Available The identification of putative liver stem cells has brought closer the previously separate fields of liver development, regeneration, and carcinogenesis. Significant overlaps in the regulation of these processes are now being described. For example, studies in embryonic liver development have already provided the basis for directed differentiation of human embryonic stem cells and induced pluripotent stem cells into hepatocyte-like cells. As a result, the understanding of the cell biology of proliferation and differentiation in the liver has been improved. This knowledge can be used to improve the function of hepatocyte-like cells for drug testing, bioartificial livers, and transplantation. In parallel, the mechanisms regulating cancer cell biology are now clearer, providing fertile soil for novel therapeutic approaches. Recognition of the relationships between development, regeneration, and carcinogenesis, and the increasing evidence for the role of stem cells in all of these areas, has sparked fresh enthusiasm in understanding the underlying molecular mechanisms and has led to new targeted therapies for liver cirrhosis and primary liver cancers.

  13. Silymarin Accelerates Liver Regeneration after Partial Hepatectomy

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    Jia-Ping Wu

    2015-01-01

    Full Text Available Partial hepatectomy (PHx is a liver regeneration physiological response induced to maintain homeostasis. Liver regeneration evolved presumably to protect wild animals from catastrophic liver loss caused by toxins or tissue injury. Silymarin (Sm ability to stimulate liver regeneration has been an object of curiosity for many years. Silymarin has been investigated for use as an antioxidant and anticarcinogen. However, its use as a supportive treatment for liver damage is elusive. In this study, we fed silymarin (Sm, 25 mg/kg to male Sprague-Dawley rats for 7 weeks. Surgical 2/3 PHx was then conducted on the rats at 6 hrs, 24 hrs, and 72 hrs. Western blot and RT-PCR were conducted to detect the cell cycle activities and silymarin effects on hepatic regeneration. The results showed that silymarin enhanced liver regeneration by accelerating the cell cycle in PHx liver. Silymarin led to increased G1 phase (cyclin D1/pRb, S phase (cyclin E/E2F, G2 phase (cyclin B, and M phase (cyclin A protein and mRNA at 6 hrs, 24 hrs, and 72 hrs PHx. HGF, TGFα, and TGFβ1 growth factor expressions were also enhanced. We suggest that silymarin plays a crucial role in accelerated liver regeneration after PHx.

  14. Chronological protein synthesis in regenerating rat liver.

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    He, Jinjun; Hao, Shuai; Zhang, Hao; Guo, Fuzheng; Huang, Lingyun; Xiao, Xueyuan; He, Dacheng

    2015-07-01

    Liver regeneration has been studied for decades; however, its regulation remains unclear. In this study, we report a dynamic tracing of protein synthesis in rat regenerating liver with a new proteomic technique, (35) S in vivo labeling analysis for dynamic proteomics (SiLAD). Conventional proteomic techniques typically measure protein alteration in accumulated amounts. The SiLAD technique specifically detects protein synthesis velocity instead of accumulated amounts of protein through (35) S pulse labeling of newly synthesized proteins, providing a direct way for analyzing protein synthesis variations. Consequently, protein synthesis within short as 30 min was visualized and protein regulations in the first 8 h of regenerating liver were dynamically traced. Further, the 3.5-5 h post partial hepatectomy (PHx) was shown to be an important regulatory turning point by acute regulation of many proteins in the initiation of liver regeneration. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Immune mediated liver failure.

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    Wang, Xiaojing; Ning, Qin

    2014-01-01

    Liver failure is a clinical syndrome of various etiologies, manifesting as jaundice, encephalopathy, coagulopathy and circulatory dysfunction, which result in subsequent multiorgan failure. Clinically, liver failure is classified into four categories: acute, subacute, acute-on-chronic and chronic liver failure. Massive hepatocyte death is considered to be the core event in the development of liver failure, which occurs when the extent of hepatocyte death is beyond the liver regenerative capacity. Direct damage and immune-mediated liver injury are two major factors involved in this process. Increasing evidence has suggested the essential role of immune-mediated liver injury in the pathogenesis of liver failure. Here, we review the evolved concepts concerning the mechanisms of immune-mediated liver injury in liver failure from human and animal studies. Both innate and adaptive immunity, especially the interaction of various immune cells and molecules as well as death receptor signaling system are discussed. In addition, we highlight the concept of "immune coagulation", which has been shown to be related to the disease progression and liver injury exacerbation in HBV related acute-on-chronic liver failure.

  16. Liver regeneration and restoration of liver function after partial hepatectomy in patients with liver tumors

    NARCIS (Netherlands)

    Jansen, P. L.; Chamuleau, R. A.; van Leeuwen, D. J.; Schipper, H. G.; Busemann-Sokole, E.; van der Heyde, M. N.

    1990-01-01

    Liver regeneration and restoration of liver function were studied in six patients who underwent partial hepatectomy with removal of 30-70% of the liver. Liver volume and liver regeneration were studied by single-photon computed tomography (SPECT), using 99mTc-colloid as tracer. The method was

  17. Towards a new therapy protocol for liver metastases. Effect of boron compounds and BNCT on normal liver regeneration

    International Nuclear Information System (INIS)

    Cardoso, Jorge E.; Heber, Elisa M.; Trivillin, Veronica A.

    2006-01-01

    The Taormina project developed a new method for BNCT treatment of multifocal unresectable liver metastases based on whole liver autograft. The Roffo Institute liver surgeons propose a new technique based on partial liver autograft that would pose less risk to the patient but would require significant healthy liver regeneration following BNCT. The aim of the present study was to assess the effect of BPA, GB-10 (Na 2 10 B 10 H 10 ) and (GB-10 + BPA) and of BNCT mediated by these boron compounds on normal liver regeneration in the Wistar rat. Normal liver regeneration, body weight, hemogram, liver and kidney function were assessed following partial hepatectomy post administration of BPA, GB-10 or (GB-10 + BPA) and post in vivo BNCT at the RA-6 Reactor. These end-points were evaluated 9 days following partial hepatectomy, the time at which complete liver regeneration occurs in untreated controls. The corresponding biodistribution studies were conducted to perform dosimetric calculations. BPA, GB-10 and (GB-10 + PBA) and in vivo BNCT mediated by these boron compounds in dose ranges compatible with therapy did not cause alterations in the outcome of normal liver regeneration, and did not induce alterations in body weight, hemogram, liver or kidney function. The experimental data available to date support the development of a new BNCT protocol for the treatment of liver metastases that requires the regeneration of normal liver past-BNCT. (author)

  18. Role of the autonomic nervous system in rat liver regeneration.

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    Xu, Cunshuan; Zhang, Xinsheng; Wang, Gaiping; Chang, Cuifang; Zhang, Lianxing; Cheng, Qiuyan; Lu, Ailing

    2011-05-01

    To study the regulatory role of autonomic nervous system in rat regenerating liver, surgical operations of rat partial hepatectomy (PH) and its operation control (OC), sympathectomy combining partial hepatectomy (SPH), vagotomy combining partial hepatectomy (VPH), and total liver denervation combining partial hepatectomy (TDPH) were performed, then expression profiles of regenerating livers at 2 h after operation were detected using Rat Genome 230 2.0 array. It was shown that the expressions of 97 genes in OC, 230 genes in PH, 253 genes in SPH, 187 genes in VPH, and 177 genes in TDPH were significantly changed in biology. The relevance analysis showed that in SPH, genes involved in stimulus response, immunity response, amino acids and K(+) transport, amino acid catabolism, cell adhesion, cell proliferation mediated by JAK-STAT, Ca(+), and platelet-derived growth factor receptor, cell growth and differentiation through JAK-STAT were up-regulated, while the genes involved in chromatin assembly and disassembly, and cell apoptosis mediated by MAPK were down-regulated. In VPH, the genes associated with chromosome modification-related transcription factor, oxygen transport, and cell apoptosis mediated by MAPK pathway were up-regulated, but the genes associated with amino acid catabolism, histone acetylation-related transcription factor, and cell differentiation mediated by Wnt pathway were down-regulated. In TDPH, the genes related to immunity response, growth and development of regenerating liver, cell growth by MAPK pathway were up-regulated. Our data suggested that splanchnic and vagal nerves could regulate the expressions of liver regeneration-related genes.

  19. Liver regeneration and restoration of liver function after partial hepatectomy in patients with liver tumors

    International Nuclear Information System (INIS)

    Jansen, P.L.M.; Chamuleau, R.A.F.; Leeuwen, D.J. van; Schippor, H.G.; Busemann-Sokole, E.; Heyde, M.N. van der

    1990-01-01

    Liver regeneration and restoration of liver function were studied in six patients who underwent partial hepatectomy with removal of 30-70% of the liver. Liver volume and liver regeneration were studied by single photon computed tomography (SPECT), using 99m Tc-colloid as tracer. The method was assessed in 11 patients by comparing the pre- and post-operative volume measurement with the volume of the resected liver mass. Liver function was determined by measuring the galactose elimination capacity and the caffeine clearance. After a postoperative follow-up period of 50 days, the liver had regenerated maximally to a volume of 75 ± 2% of the preoperative liver mass. Maximal restoration of liver function was achieved 120 days after operation and amounted to 75 ± 10% for the caffeine clearance and to 100 ± 25% for the galactose elimination capacity. This study shows that SPECT is a useful method for assessing liver regeneration in patients after partial hepatectomy. The study furthermore shows that caffeine clearance correlates well with total liver volume, whereas the galactose elimination capacity overestimates total liver volume after partial hepatectomy. 22 refs

  20. Delayed liver regeneration after partial hepatectomy in adiponectin knockout mice

    International Nuclear Information System (INIS)

    Ezaki, Hisao; Yoshida, Yuichi; Saji, Yukiko; Takemura, Takayo; Fukushima, Juichi; Matsumoto, Hitoshi; Kamada, Yoshihiro; Wada, Akira; Igura, Takumi; Kihara, Shinji; Funahashi, Tohru; Shimomura, Iichiro; Tamura, Shinji; Kiso, Shinichi; Hayashi, Norio

    2009-01-01

    We previously demonstrated that adiponectin has anti-fibrogenic and anti-inflammatory effects in the liver of mouse models of various liver diseases. However, its role in liver regeneration remains unclear. The aim of this study was to determine the role of adiponectin in liver regeneration. We assessed liver regeneration after partial hepatectomy in wild-type (WT) and adiponectin knockout (KO) mice. We analyzed DNA replication and various signaling pathways involved in cell proliferation and metabolism. Adiponectin KO mice exhibited delayed DNA replication and increased lipid accumulation in the regenerating liver. The expression levels of peroxisome proliferator-activated receptor (PPAR) α and carnitine palmitoyltransferase-1 (CPT-1), a key enzyme in mitochondrial fatty acid oxidation, were decreased in adiponectin KO mice, suggesting possible contribution of altered fat metabolism to these phenomena. Collectively, the present results highlight a new role for adiponectin in the process of liver regeneration.

  1. Liver regeneration is dependent on the extent of hepatectomy

    DEFF Research Database (Denmark)

    Meier, Michelle; Knudsen, Anders Riegels; Andersen, Kasper Jarlhelt

    of liver tissue and blood for liver specific serology. The change in liver weight after PH was evaluated as liver regeneration rate (RR). Histological analyses of liver cell proliferation and proteomic analyses are in progress. The gain in liver weight as well as RR increased significantly with the size......The upper limit for the size of hepatectomy is approximately 90% in rats. The present research project is designed to investigate the molecular pathways leading to either liver regeneration or liver failure after extended hepatectomy. In this first study we investigated the impact of different size...... of hepatectomy on liver regeneration in a rat model. Male Wistar rats were divided into four groups: 30% (n=24), 70% (n=24) and 90% (n=24) partial hepatectomy (PH) was performed together with a SHAM group (n=24). Euthanization took place at postoperative day (POD) 1 (n=8), 3 (n=8), and 5 (n=8) with harvesting...

  2. Immune mediated liver failure

    OpenAIRE

    Wang, Xiaojing; Ning, Qin

    2014-01-01

    Liver failure is a clinical syndrome of various etiologies, manifesting as jaundice, encephalopathy, coagulopathy and circulatory dysfunction, which result in subsequent multiorgan failure. Clinically, liver failure is classified into four categories: acute, subacute, acute-on-chronic and chronic liver failure. Massive hepatocyte death is considered to be the core event in the development of liver failure, which occurs when the extent of hepatocyte death is beyond the liver regenerative capac...

  3. Understanding Liver Regeneration: From Mechanisms to Regenerative Medicine.

    Science.gov (United States)

    Gilgenkrantz, Hélène; Collin de l'Hortet, Alexandra

    2018-04-16

    Liver regeneration is a complex and unique process. When two-thirds of a mouse liver is removed, the remaining liver recovers its initial weight in approximately 10 days. The understanding of the mechanisms responsible for liver regeneration may help patients needing large liver resections or transplantation and may be applied to the field of regenerative medicine. All differentiated hepatocytes are capable of self-renewal, but different subpopulations of hepatocytes seem to have distinct proliferative abilities. In the setting of chronic liver diseases, a ductular reaction ensues in which liver progenitor cells (LPCs) proliferate in the periportal region. Although these LPCs have the capacity to differentiate into hepatocytes and biliary cells in vitro, their ability to participate in liver regeneration is far from clear. Their expansion has even been associated with increased fibrosis and poorer prognosis in chronic liver diseases. Controversies also remain on their origin: lineage studies in experimental mouse models of chronic injury have recently suggested that these LPCs originate from hepatocyte dedifferentiation, whereas in other situations, they seem to come from cholangiocytes. This review summarizes data published in the past 5 years in the liver regeneration field, discusses the mechanisms leading to regeneration disruption in chronic liver disorders, and addresses the potential use of novel approaches for regenerative medicine. Copyright © 2018 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  4. Hepatic regeneration after sublethal partial liver irradiation in cirrhotic rats

    International Nuclear Information System (INIS)

    Gu Ke; Lai Songtao; Ma Ningyi; Zhao Jiandong; Ren Zhigang; Wang Jian; Liu Jin; Jiang Guoliang

    2011-01-01

    Our previous animal study had demonstrated that partial liver irradiation (IR) could stimulate regeneration in the protected liver, which supported the measurements adopted in radiotherapy planning for hepatocellular carcinoma. The purpose of this present study is to investigate whether cirrhotic liver repopulation could be triggered by partial liver IR. The cirrhosis was induced by thioacetamide (TAA) in rats. After cirrhosis establishment, TAA was withdrawn. In Experiment 1, only right-half liver was irradiated with single doses of 5 Gy, 10 Gy and 15 Gy, respectively. In Experiment 2, right-half liver was irradiated to 15 Gy, and the left-half to 2.5 Gy, 5 Gy and 7.5 Gy, respectively. The regeneration endpoints, including liver index (LI); mitotic index (MI); liver proliferation index (LPI); proliferating cell nuclear antigen-labeling index (PCNA-LI); serum hepatic growth factor (HGF), vascular endothelial growth factor (VEGF), transforming growth factor (TGF)-α and interleukin (IL)-6, were evaluated on 0 day, 30-day, 60-day, 90-day, 120-day and 150-day after IR. Serum and in situ TGF-β1 were also measured. In both experimental groups, the IR injuries were sublethal, inducing no more than 9% animal deaths. Upon TAA withdrawal, hepatic regeneration decelerated in the controls. In Experiment 1 except for LI, all other regeneration parameters were significantly higher than those in controls for both right-half and left-half livers. In Experiment 2 all regeneration parameters were also higher compared with those in controls for both half livers. Serum HGF and VEGF were increased compared with that of controls. Both unirradiated and low dose-irradiated cirrhotic liver were able to regenerate triggered by sublethal partial liver IR and higher doses and IR to both halves liver triggered a more enhanced regeneration. (author)

  5. Anti-inflammatory liposomes have no impact on liver regeneration in rats

    DEFF Research Database (Denmark)

    Jepsen, Betina Norman; Andersen, Kasper Jarlhelt; Knudsen, Anders Riegels

    2015-01-01

    Introduction: Surgical resection is the gold standard in treatment of hepatic malignancies, giving the patient the best chance to be cured. The liver has a unique capacity to regenerate. However, an inflammatory response occurs during resection, in part mediated by Kupffer cells, that influences...... the speed of regeneration. The aim of this study was to investigate the effect of a Kupffer cell targeted anti-inflammatory treatment on liver regeneration in rats. Methods: Two sets of animals, each including four groups of eight rats, were included. Paired groups from each set received treatment......-6. Conclusion: Low dose dexamethasone targeted to Kupffer cells does not affect histological liver cell regeneration after 70% hepatectomy in rats, but reduces the inflammatory response judged by circulating markers of inflammation. (C) 2015 The Authors. Published by Elsevier Ltd on behalf of IJS...

  6. The genetic regulation of the terminating phase of liver regeneration

    DEFF Research Database (Denmark)

    Nygård, Ingvild E.; Mortensen, Kim E.; Hedegaard, Jakob

    2012-01-01

    Background After partial hepatectomy (PHx), the liver regeneration process terminates when the normal liver-mass/body-weight ratio of 2.5% has been re-established. To investigate the genetic regulation of the terminating phase of liver regeneration, we performed a 60% PHx in a porcine model. Liver...... biopsies were taken at the time of resection, after three weeks and upon termination the sixth week. Gene expression profiles were obtained using porcine oligonucleotide microarrays. Our study reveals the interactions between genes regulating the cell cycle, apoptosis and angiogenesis, and the role...... of Transforming Growth Factor-β (TGF-β) signalling towards the end of liver regeneration. Results Microarray analysis revealed a dominance of genes regulating apoptosis towards the end of regeneration. Caspase Recruitment Domain-Containing Protein 11 (CARD11) was up-regulated six weeks after PHx, suggesting...

  7. Impaired lipid accumulation in the liver of Tsc2-heterozygous mice during liver regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Obayashi, Yoko, E-mail: youko_oobayashi@ajinomoto.com [Department of Pathology, University of Washington School of Medicine, Seattle, WA (United States); Campbell, Jean S.; Fausto, Nelson [Department of Pathology, University of Washington School of Medicine, Seattle, WA (United States); Yeung, Raymond S. [Department of Surgery, University of Washington School of Medicine, Seattle, WA (United States)

    2013-07-19

    Highlights: •Tuberin phosphorylation correlated with mTOR activation in early liver regeneration. •Liver regeneration in the Tsc2+/− mice was not enhanced. •The Tsc2+/− livers failed to accumulate lipid bodies during liver regeneration. •Mortality rate increased in Tsc2+/− mice after partial hepatectomy. •Tuberin plays a critical role in hepatic lipid accumulation to support regeneration. -- Abstract: Tuberin is a negative regulator of mTOR pathway. To investigate the function of tuberin during liver regeneration, we performed 70% hepatectomy on wild-type and Tsc2+/− mice. We found the tuberin phosphorylation correlated with mTOR activation during early liver regeneration in wild-type mice. However, liver regeneration in the Tsc2+/− mice was not enhanced. Instead, the Tsc2+/− livers failed to accumulate lipid bodies, and this was accompanied by increased mortality. These findings suggest that tuberin plays a critical role in liver energy balance by regulating hepatocellular lipid accumulation during early liver regeneration. These effects may influence the role of mTORC1 on cell growth and proliferation.

  8. Impact of future remnant liver volume on post-hepatectomy regeneration in non-cirrhotic livers

    Directory of Open Access Journals (Sweden)

    Duilio ePagano

    2014-04-01

    Full Text Available Objective: The purpose of the study is to detect if some parameters can be considered as predictors of liver regeneration in two different patient populations composed of in living donors for adult to adult living donor liver transplant and patients with hepatic malignancies within a single institution.Summary Background Data: Preoperative multi-detector computed tomography volumetry is an essential tool to assess the volume of the remnant liver. Methods: a retrospective analysis from an ongoing clinical study on 100 liver resections, between 2004 and 2010. 70 patients were right lobe living donors for liver transplantation and 30 patients were resected for treatment of tumors. Pre-surgical factors such as age, weight, height, body mass index (BMI, original liver volume, future remnant liver volume (FRLV, spleen volume, liver function tests, creatinine, platelet count, steatosis, portal vein embolization (PVE and number of resected segments were analyzed to evidence potential markers for liver regeneration. Results: Follow-up period did not influence the amount of liver regenerated: the linear regression evidenced that there is no correlation between percentage of liver regeneration and time of follow-up (p=0.88. The pre-surgical variables that resulted markers of liver regeneration include higher preoperative values of BMI (p=0.01, bilirubin(p=0.04, glucose (p=0.05 and GGT (p=0.014; the most important association was revealed regarding the lower FRLV (pConclusions: Liver regeneration follows similar pathway in living donor and in patients resected for cancer. Small FRLV tends to regenerate more and faster, confirming that a larger resections may lead to a greater promotion of liver regeneration in patients with optimal conditions in terms of body habitus, preoperative liver function tests and glucose level.

  9. Chronic stress does not impair liver regeneration in rats

    DEFF Research Database (Denmark)

    Andersen, Kasper J; Knudsen, Anders Riegels; Wiborg, Ove

    2015-01-01

    a 70 % partial hepatectomy (PHx). The animals were evaluated on postoperative day 2 or 4. Blood samples were collected to examine circulating markers of inflammation and liver cell damage. Additionally, liver tissues were sampled to evaluate liver weight and regeneration rate. RESULTS: None......BACKGROUND: Although wound healing is a simple regenerative process that is critical after surgery, it has been shown to be impaired under psychological stress. The liver has a unique capacity to regenerate through highly complex mechanisms. The aim of this study was to investigate the effects...... of chronic stress, which may induce a depression-like state, on the complex process of liver regeneration in rats. METHODS: Twenty rats were included in this study. The animals received either a standard housing protocol or were subjected to a Chronic Mild Stress (CMS) stress paradigm. All rats underwent...

  10. Epidermal growth factor receptor restoration rescues the fatty liver regeneration in mice.

    Science.gov (United States)

    Zimmers, Teresa A; Jin, Xiaoling; Zhang, Zongxiu; Jiang, Yanlin; Koniaris, Leonidas G

    2017-10-01

    Hepatic steatosis is a common histological finding in obese patients. Even mild steatosis is associated with delayed hepatic regeneration and poor outcomes following liver resection or transplantation. We sought to identify and target molecular pathways that mediate this dysfunction. Lean mice and mice made obese through feeding of a high-fat, hypercaloric diet underwent 70 or 80% hepatectomy. After 70% resection, obese mice demonstrated 100% survival but experienced increased liver injury, reduced energy stores, reduced mitoses, increased necroapoptosis, and delayed recovery of liver mass. Increasing liver resection to 80% was associated with mortality of 40% in lean and 80% in obese mice ( P steatosis might promote liver regeneration and survival following hepatic resection or transplantation. Copyright © 2017 the American Physiological Society.

  11. Impact of NKT Cells and LFA-1 on Liver Regeneration under Subseptic Conditions.

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    Ann-Kathrin Jörger

    Full Text Available Activation of the immune system in terms of subseptic conditions during liver regeneration is of paramount clinical importance. However, little is known about molecular mechanisms and their mediators that control hepatocyte proliferation. We sought to determine the functional role of immune cells, especially NKT cells, in response to partial hepatectomy (PH, and to uncover the impact of the integrin lymphocyte function-associated antigen-1 (LFA-1 on liver regeneration in a subseptic setting.Wild-type (WT and LFA-1-/- mice underwent a 2/3 PH and low-dose lipopolysaccharid (LPS application. Hepatocyte proliferation, immune cell infiltration, and cytokine profile in the liver parenchyma were determined.Low-dose LPS application after PH results in a significant delay of liver regeneration between 48h and 72h, which is associated with a reduced number of CD3+ cells within the regenerating liver. In absence of LFA-1, an impaired regenerative capacity was observed under low-dose LPS application. Analysis of different leukocyte subpopulations showed less CD3+NK1.1+ NKT cells in the liver parenchyma of LFA-1-/- mice after PH and LPS application compared to WT controls, while CD3-NK1.1+ NK cells markedly increased. Concordantly with this observation, lower levels of NKT cell related cytokines IL-12 and IL-23 were expressed in the regenerating liver of LFA-1-/- mice, while the expression of NK cell-associated CCL5 and IL-10 was increased compared to WT mice.A subseptic situation negatively alters hepatocyte proliferation. Within this scenario, we suggest an important impact of NKT cells and postulate a critical function for LFA-1 during processes of liver regeneration.

  12. JNK1 induces hedgehog signaling from stellate cells to accelerate liver regeneration in mice.

    Science.gov (United States)

    Langiewicz, Magda; Graf, Rolf; Humar, Bostjan; Clavien, Pierre A

    2018-04-27

    To improve outcomes of two-staged hepatectomies for large/multiple liver tumors, portal vein ligation (PVL) has been combined with parenchymal transection (coined ALPPS; Associated Liver Partition and Portal vein ligation for Staged hepatectomy) to greatly accelerate liver regeneration. In a novel ALPPS mouse model, we have reported paracrine Indian hedgehog (IHH) signaling from stellate cells as an early contributor to augmented regeneration. Here, we sought to identify upstream regulators of IHH. ALPPS in mice was compared against PVL and additional control surgeries. Potential IHH regulators were identified through in silico mining of transcriptomic data. JNK1 activity was reduced through SP600125 to evaluate its effects on IHH signaling. Recombinant IHH was injected after JNK diminution to substantiate their relationship during accelerated liver regeneration. Mining linked Ihh to Mapk8. JNK1 upregulation after ALPPS was validated and preceded the IHH peak. On immunofluorescence, JNK1 and IHH co-localized in ASMA-positive non-parenchymal cells. Inhibition of JNK1 prior to ALPPS surgery reduced liver weight gain to PVL levels and was accompanied by downregulation of hepatocellular proliferation and the IHH-GLI1-CCND1 axis. In JNK1-inhibited mice, recombinant IHH restored ALPPS-like acceleration of regeneration and re-elevated JNK1 activity, suggesting the presence of a positive IHH-JNK1 feedback loop. JNK1-mediated induction of IHH paracrine signaling from HSCs is essential for accelerated regeneration of parenchymal mass. The JNK1-IHH axis is a mechanism unique to ALPPS surgery and may point to therapeutic alternatives for patients with insufficient regenerative capacity. ALPPS, a novel two-staged hepatectomy, induces an unprecedented acceleration of liver regeneration to enable treatment of unresectable liver tumors. Here, we demonstrate JNK1-IHH signaling as a mechanism underlying the regenerative acceleration induced by ALPPS. Copyright © 2018 European

  13. Expression and localization of regenerating gene I in a rat liver regeneration model

    International Nuclear Information System (INIS)

    Wang Jingshu; Koyota, Souichi; Zhou, Xiaoping; Ueno, Yasuharu; Ma Li; Kawagoe, Masami; Koizumi, Yukio; Okamoto, Hiroshi; Sugiyama, Toshihiro

    2009-01-01

    Regenerating gene (Reg) I has been identified as a regenerative/proliferative factor for pancreatic islet cells. We examined Reg I expression in the regenerating liver of a rat model that had been administered 2-acetylaminofluorene and treated with 70% partial hepatectomy (2-AAF/PH model), where hepatocyte and cholangiocyte proliferation was suppressed and the hepatic stem cells and/or hepatic progenitor cells were activated. In a detailed time course study of activation of hepatic stem cells in the 2-AAF/PH model, utilizing immunofluorescence staining with antibodies of Reg I and other cell-type-specific markers, we found that Reg I-expressing cells are present in the bile ductules and increased during regeneration. Reg I-expressing cells were colocalized with CK19, OV6, and AFP. These results demonstrate that Reg I is significantly upregulated in the liver of the 2-AAF/PH rat model, accompanied by the formation of bile ductules during liver regeneration.

  14. Cellular Mechanisms of Liver Regeneration and Cell-Based Therapies of Liver Diseases

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    Irina V. Kholodenko

    2017-01-01

    Full Text Available The emerging field of regenerative medicine offers innovative methods of cell therapy and tissue/organ engineering as a novel approach to liver disease treatment. The ultimate scientific foundation of both cell therapy of liver diseases and liver tissue and organ engineering is delivered by the in-depth studies of the cellular and molecular mechanisms of liver regeneration. The cellular mechanisms of the homeostatic and injury-induced liver regeneration are unique. Restoration of the mass of liver parenchyma is achieved by compensatory hypertrophy and hyperplasia of the differentiated parenchymal cells, hepatocytes, while expansion and differentiation of the resident stem/progenitor cells play a minor or negligible role. Participation of blood-borne cells of the bone marrow origin in liver parenchyma regeneration has been proven but does not exceed 1-2% of newly formed hepatocytes. Liver regeneration is activated spontaneously after injury and can be further stimulated by cell therapy with hepatocytes, hematopoietic stem cells, or mesenchymal stem cells. Further studies aimed at improving the outcomes of cell therapy of liver diseases are underway. In case of liver failure, transplantation of engineered liver can become the best option in the foreseeable future. Engineering of a transplantable liver or its major part is an enormous challenge, but rapid progress in induced pluripotency, tissue engineering, and bioprinting research shows that it may be doable.

  15. CXC chemokines function as a rheostat for hepatocyte proliferation and liver regeneration.

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    Gregory C Wilson

    Full Text Available Our previous in vitro studies have demonstrated dose-dependent effects of CXCR2 ligands on hepatocyte cell death and proliferation. In the current study, we sought to determine if CXCR2 ligand concentration is responsible for the divergent effects of these mediators on liver regeneration after ischemia/reperfusion injury and partial hepatectomy.Murine models of partial ischemia/reperfusion injury and hepatectomy were used to study the effect of CXCR2 ligands on liver regeneration.We found that hepatic expression of the CXCR2 ligands, macrophage inflammatory protein-2 (MIP-2 and keratinocyte-derived chemokine (KC, was significantly increased after both I/R injury and partial hepatectomy. However, expression of these ligands after I/R injury was 30-100-fold greater than after hepatectomy. Interestingly, the same pattern of expression was found in ischemic versus non-ischemic liver lobes following I/R injury with expression significantly greater in the ischemic liver lobes. In both systems, lower ligand expression was associated with increased hepatocyte proliferation and liver regeneration in a CXCR2-dependent fashion. To confirm that these effects were related to ligand concentration, we administered exogenous MIP-2 and KC to mice undergoing partial hepatectomy. Mice received a "high" dose that replicated serum levels found after I/R injury and a "low" dose that was similar to that found after hepatectomy. Mice receiving the "high" dose had reduced levels of hepatocyte proliferation and regeneration whereas the "low" dose promoted hepatocyte proliferation and regeneration.Together, these data demonstrate that concentrations of CXC chemokines regulate the hepatic proliferative response and subsequent liver regeneration.

  16. Sirolimus influence on hepatectomy-induced liver regeneration in rats

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    Edimar Leandro Toderke

    Full Text Available OBJECTIVE: To evaluate the influence of sirolimus on liver regeneration triggered by resection of 70% of the liver of adult rats. METHODS: we used 40 Wistar rats randomly divided into two groups (study and control, each group was divided into two equal subgroups according to the day of death (24 hours and seven days. Sirolimus was administered at a dose of 1mg/kg in the study group and the control group was given 1 ml of saline. The solutions were administered daily since three days before hepatectomy till the rats death to removal of the regenerated liver, conducted in 24 hours or 7 days after hepatectomy. Liver regeneration was measured by the KWON formula, by thenumber of mitotic figures (hematoxylin-eosin staining and by the immunohistochemical markers PCNA and Ki-67. RESULTS: there was a statistically significant difference between the 24h and the 7d groups. When comparing the study and control groups in the same period, there was a statistically significant variation only for Ki-67, in which there were increased numbers of hepatocytes in cell multiplication in the 7d study group compared with the 7d control group (p = 0.04. CONCLUSION: there was no negative influence of sirolimus in liver regeneration and there was a positive partial effect at immunohistochemistry with Ki-67.

  17. Sex Hormone-Related Functions in Regenerating Male Rat Liver

    Science.gov (United States)

    FRANCAVILLA, ANTONIO; EAGON, PATRICIA K.; DiLEO, ALFREDO; POLIMENO, LORENZO; PANELLA, CARMINE; AQUILINO, A. MARIA; INGROSSO, MARCELLO; Van THIEL, DAVID H.; STARZL, THOMAS E.

    2011-01-01

    Sex hormone receptors were quantitated in normal male rat liver and in regenerating liver at several different times after partial (70%) hepatectomy. Both estrogen and androgen receptor content were altered dramatically by partial hepatectomy. Total hepatic content and nuclear retention of estrogen receptors increased, with the zenith evident 2 days after partial hepatectomy, corresponding to the zenith of mitotic index. Serum estradiol increased after 1 day, and reached a maximum at 3 days after surgery. In contrast, total and nuclear androgen receptor content demonstrated a massive decline at 1, 2, and 3 days after resection. Serum testosterone displayed a parallel decline. In addition, hepatic content of two androgen-responsive proteins was reduced to 15% and 13% of normal values during this period. The activity of these various proteins during regeneration of male rat liver is comparable to that observed in the liver of normal female rats. Taken together, these results indicate that partial hepatectomy induces a feminization of certain sexually dimorphic aspects of liver function in male rats. Furthermore, these data provide evidence that estrogens, but not androgens, may have an important role in the process of liver regeneration. PMID:3758617

  18. The combined effect of erythropoietin and granulocyte macrophage colony stimulating factor on liver regeneration after major hepatectomy in rats

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    Frangou Matrona

    2010-07-01

    Full Text Available Abstract Background The liver presents a remarkable capacity for regeneration after hepatectomy but the exact mechanisms and mediators involved are not yet fully clarified. Erythropoietin (EPO and Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF have been shown to promote liver regeneration after major hepatectomy. Aim of this experimental study is to compare the impact of exogenous administration of EPO, GM-CSF, as well as their combination on the promotion of liver regeneration after major hepatectomy. Methods Wistar rats were submitted to 70% major hepatectomy. The animals were assigned to 4 experimental groups: a control group (n = 21 that received normal saline, an EPO group (n = 21, that received EPO 500 IU/kg, a GM-CSF group (n = 21 that received 20 mcg/kg of GM-CSF and a EPO+GMCSF group (n = 21 which received a combination of the above. Seven animals of each group were killed on the 1st, 3rd and 7th postoperative day and their remnant liver was removed to evaluate liver regeneration by immunochemistry for PCNA and Ki 67. Results Our data suggest that EPO and GM-CSF increases liver regeneration following major hepatectomy when administered perioperatively. EPO has a more significant effect than GM-CSF (p Conclusion EPO, GM-CSF and their combination enhance liver regeneration after hepatectomy in rats when administered perioperatively. However their combination has a weaker effect on liver regeneration compared to EPO alone. Further investigation is needed to assess the exact mechanisms that mediate this finding.

  19. Whither prometheus' liver? Greek myth and the science of regeneration.

    Science.gov (United States)

    Power, Carl; Rasko, John E J

    2008-09-16

    Stem-cell biologists and those involved in regenerative medicine are fascinated by the story of Prometheus, the Greek god whose immortal liver was feasted on day after day by Zeus' eagle. This myth invariably provokes the question: Did the ancient Greeks know about the liver's amazing capacity for self-repair? The authors address this question by exploring the origins of Greek myth and medicine, adopting a 2-fold strategy. First, the authors consider what opportunities the ancient Greeks had to learn about the liver's structure and function. This involves a discussion of early battlefield surgery, the beginnings of anatomical research, and the ancient art of liver augury. In addition, the authors consider how the Greeks understood Prometheus' immortal liver. Not only do the authors examine the general theme of regeneration in Greek mythology, they survey several scholarly interpretations of Prometheus' torture.

  20. Effects of Combined Anisodamine and Neostigmine Treatment on the Inflammatory Response and Liver Regeneration of Obstructive Jaundice Rats after Hepatectomy

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    Chong-Hui Li

    2014-01-01

    Full Text Available Background. Cholestasis is associated with high rates of morbidity and mortality in patients undergoing major liver resection. This study aimed to evaluate the effects of a combined anisodamine and neostigmine (Ani+Neo treatment on the inflammatory response and liver regeneration in rats with obstructive jaundice (OJ after partial hepatectomy. Materials and Methods. OJ was induced in the rats by bile duct ligation. After 7 days biliary drainage and partial hepatectomy were performed. These rats were assigned to a saline group or an Ani+Neo treatment group. The expressions of inflammatory mediators, liver regeneration, and liver damage were assessed at 48 h after hepatectomy. Results. The mRNA levels of TNF-α, IL-1β, IL-6, MCP-1, and MIP-1α, in the remnant livers, and the serum levels of TNF-α and IL-1β were substantially reduced in the Ani+Neo group compared with saline group (P<0.05. The Ani+Neo treatment obviously promoted liver regeneration as indicated by the liver weights and Ki-67 labeling index (P<0.05. The serum albumin and γ-GT levels and liver neutrophil infiltration also significantly improved in the Ani+Neo group (P<0.05 compared with the saline group. Conclusions. These results demonstrate that the combined anisodamine and neostigmine treatment is able to improve the liver regeneration in rats with OJ by substantially alleviating the inflammatory response.

  1. LIVER AND BONE MARROW STEM/PROGENITOR CELLS AS REGULATORS OF REPARATIVE REGENERATION OF DAMAGED LIVER

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    А. V. Lundup

    2010-01-01

    Full Text Available In this review the modern information about effectiveness of liver insufficiency treatment by stem/ progenitor cells of liver (oval cells and bone marrow (hemopoietic cells and mesenchymal cells was presented. It is shown that medical action of these cells is referred on normalization of liver cell interaction and reorganization of processes of a reparative regeneration in damaged liver. It is believed that application of mesenchymal stromal cells from an autological bone marrow is the most perspective strategy. However, for definitive judgement about regenerative possibilities of the autological bone marrow cells it is necessary to carry out large-scale double blind clinical researches. 

  2. Augmenter of liver regeneration (ALR) protects human hepatocytes against apoptosis

    International Nuclear Information System (INIS)

    Ilowski, Maren; Kleespies, Axel; Toni, Enrico N. de; Donabauer, Barbara; Jauch, Karl-Walter; Hengstler, Jan G.; Thasler, Wolfgang E.

    2011-01-01

    Research highlights: → ALR decreases cytochrome c release from mitochondria. → ALR protects hepatocytes against apoptosis induction by ethanol, TRAIL, anti-Apo, TGF-β and actinomycin D. → ALR exerts a liver-specific anti-apoptotic effect. → A possible medical usage of ALR regarding protection of liver cells during apoptosis inducing therapies. -- Abstract: Augmenter of liver regeneration (ALR) is known to support liver regeneration and to stimulate proliferation of hepatocytes. However, it is not known if ALR exerts anti-apoptotic effects in human hepatocytes and whether this protective effect is cell type specific. This is relevant, because compounds that protect the liver against apoptosis without undesired effects, such as protection of metastatic tumour cells, would be appreciated in several clinical settings. Primary human hepatocytes (phH) and organotypic cancer cell lines were exposed to different concentrations of apoptosis inducers (ethanol, TRAIL, anti-Apo, TGF-β, actinomycin D) and cultured with or without recombinant human ALR (rhALR). Apoptosis was evaluated by the release of cytochrome c from mitochondria and by FACS with propidium iodide (PI) staining. ALR significantly decreased apoptosis induced by ethanol, TRAIL, anti-Apo, TGF-β and actinomycin D. Further, the anti-apoptotic effect of ALR was observed in primary human hepatocytes and in HepG2 cells but not in bronchial (BC1), colonic (SW480), gastric (GC1) and pancreatic (L3.6PL) cell lines. Therefore, the hepatotrophic growth factor ALR acts in a liver specific manner with regards to both its mitogenic and its anti-apoptotic effect. Unlike the growth factors HGF and EGF, rhALR acts in a liver specific manner. Therefore, ALR is a promising candidate for further evaluation as a possible hepatoprotective factor in clinical settings.

  3. Augmenter of liver regeneration (ALR) protects human hepatocytes against apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Ilowski, Maren [Liver Regeneration Group, Department of Surgery, Grosshadern Hospital, Ludwig Maximilians University, Munich (Germany); Kleespies, Axel [Department of Surgery, Grosshadern Hospital, Ludwig Maximilians University, Munich (Germany); Toni, Enrico N. de [Department of Medicine II, Grosshadern Hospital, Ludwig Maximilians University, Munich (Germany); Donabauer, Barbara [Liver Regeneration Group, Department of Surgery, Grosshadern Hospital, Ludwig Maximilians University, Munich (Germany); Jauch, Karl-Walter [Department of Surgery, Grosshadern Hospital, Ludwig Maximilians University, Munich (Germany); Hengstler, Jan G. [Leibniz Research Centre for Working Environment and Human Factors, Technical University, Dortmund (Germany); Thasler, Wolfgang E., E-mail: wolfgang.thasler@med.uni-muenchen.de [Liver Regeneration Group, Department of Surgery, Grosshadern Hospital, Ludwig Maximilians University, Munich (Germany); Department of Surgery, Grosshadern Hospital, Ludwig Maximilians University, Munich (Germany)

    2011-01-07

    Research highlights: {yields} ALR decreases cytochrome c release from mitochondria. {yields} ALR protects hepatocytes against apoptosis induction by ethanol, TRAIL, anti-Apo, TGF-{beta} and actinomycin D. {yields} ALR exerts a liver-specific anti-apoptotic effect. {yields} A possible medical usage of ALR regarding protection of liver cells during apoptosis inducing therapies. -- Abstract: Augmenter of liver regeneration (ALR) is known to support liver regeneration and to stimulate proliferation of hepatocytes. However, it is not known if ALR exerts anti-apoptotic effects in human hepatocytes and whether this protective effect is cell type specific. This is relevant, because compounds that protect the liver against apoptosis without undesired effects, such as protection of metastatic tumour cells, would be appreciated in several clinical settings. Primary human hepatocytes (phH) and organotypic cancer cell lines were exposed to different concentrations of apoptosis inducers (ethanol, TRAIL, anti-Apo, TGF-{beta}, actinomycin D) and cultured with or without recombinant human ALR (rhALR). Apoptosis was evaluated by the release of cytochrome c from mitochondria and by FACS with propidium iodide (PI) staining. ALR significantly decreased apoptosis induced by ethanol, TRAIL, anti-Apo, TGF-{beta} and actinomycin D. Further, the anti-apoptotic effect of ALR was observed in primary human hepatocytes and in HepG2 cells but not in bronchial (BC1), colonic (SW480), gastric (GC1) and pancreatic (L3.6PL) cell lines. Therefore, the hepatotrophic growth factor ALR acts in a liver specific manner with regards to both its mitogenic and its anti-apoptotic effect. Unlike the growth factors HGF and EGF, rhALR acts in a liver specific manner. Therefore, ALR is a promising candidate for further evaluation as a possible hepatoprotective factor in clinical settings.

  4. Evaluation of regeneration of liver function in pig model of auxiliary partial liver transplantation

    International Nuclear Information System (INIS)

    Li Jiaxin; Chen Xiaopeng; Rui Ging; Shong Qun; Chen Fangman; Lu Meijing; Chen Yongquan

    2010-01-01

    Objective: To establish a pig model of auxiliary partial liver transplantation and observe the liver function regeneration of host liver and graft. Methods: The portal vein providing for the host liver were gradually contracted; the donor hepatic veins were eng-to-side anastomosed to inferior vena cava in host caudal; graft was transplanted into the space under the host liver, part of receivers relieved portal vein angiography and color Doppler flow imaging was performed 3 days after surgery. Liver function of double livers in relievers was checked up, 3 days and 1 week after surgery respectively. Results: After surgery 10 relievers survived over 1 week, blood enzymology from hepatic vein of grafts 1 week after surgery were not ameliorative significantly compared with those 3 days after surgery (P > 0.05). Blood enzymology indexes from hepatic veins of grafts 1 week after surgery were were improved significantly compared with 3 days after surgery (P < 0.05). The graft did not reveal atrophic and gained favorable function. Conclusion: Favorable regeneration in the auxiliary partial liver transplantation model has achieved. Ideal foundation has been established for simulating and investigating human auxiliary liver transplantation. (authors)

  5. Stem cell  mediated liver regeneration:

    DEFF Research Database (Denmark)

    Jelnes, Peter

    udformet en strategi som involverede isolering af HPCr vha. Fluorescent Activated Cell Sorting (FACS). Isolerede celler skulle efterfølgende undersøges ved in vitro studier som implicerede tilsætning af specifikke immunrespons relaterede faktorer. Kun få specifikke overflade HPC markører er blevet...

  6. Changes at transcriptional level during liver regeneration in the rat

    International Nuclear Information System (INIS)

    Subba Rao, M.N.; Netrawali, M.S.; Pradhan, D.S.; Sreenivasan, A.

    1976-01-01

    A great upheaval in RNA synthetic pattern is known to occur during the early periods after partial hepatectomy. Such changes are being studied in regenerating rat liver with a view to understanding regulatory mechanisms of eukaryotic transcription. Follwoing partial hepatectomy, RNA synthesis is rat liver showed graded increase during 4 to 18 hours. At these time intervals, a significant enhancement could be discerned both in template efficiency of chromatin and in RNA polymerase activity in this tissue. Further examination revealed that the activity of RNA polymerase II (extra-nucleolar enzyme) stimulated to a much greater extent as compared to that of RNA polymerase I (nucleolar enzyme). Partial hepatectomy also resulted in significant alterations in turnovers of chromosomal acidic proteins in liver. 32 P-orthophosphate injected intraperitoneally was used in these studies. (author)

  7. Influence of epidermal growth factor on liver regeneration after partial hepatectomy in rats

    DEFF Research Database (Denmark)

    Olsen, Peter Skov; Boesby, S.; Kirkegaard, P.

    2013-01-01

    The role of epidermal growth factor on liver regeneration after partial hepatectomy in rats was investigated. After a 70% hepatectomy in rats, the concentration of epidermal growth factor in portal venous blood was unchanged compared with unoperated controls. However, small amounts of epidermal...... growth factor could be identified in portal venous blood after intestinal instillation of epidermal growth factor. Brunner's glands and the submandibular glands secrete epidermal growth factor. Extirpation of Brunner's glands decreased liver regeneration, whereas removal of the submandibular glands had...... no effect on liver regeneration. Epidermal growth factor antiserum reduced liver regeneration significantly. Oral or s.c. administration of epidermal growth factor had no effect on liver regeneration, whereas epidermal growth factor enhanced the effect of insulin and glucagon on liver regeneration...

  8. Farnesoid X receptor, the bile acid sensing nuclear receptor, in liver regeneration

    Directory of Open Access Journals (Sweden)

    Guodong Li

    2015-03-01

    Full Text Available The liver is unique in regenerative potential, which could recover the lost mass and function after injury from ischemia and resection. The underlying molecular mechanisms of liver regeneration have been extensively studied in the past using the partial hepatectomy (PH model in rodents, where 2/3 PH is carried out by removing two lobes. The whole process of liver regeneration is complicated, orchestrated event involving a network of connected interactions, which still remain fully elusive. Bile acids (BAs are ligands of farnesoid X receptor (FXR, a nuclear receptor of ligand-activated transcription factor. FXR has been shown to be highly involved in liver regeneration. BAs and FXR not only interact with each other but also regulate various downstream targets independently during liver regeneration. Moreover, recent findings suggest that tissue-specific FXR also contributes to liver regeneration significantly. These novel findings suggest that FXR has much broader role than regulating BA, cholesterol, lipid and glucose metabolism. Therefore, these researches highlight FXR as an important pharmaceutical target for potential use of FXR ligands to regulate liver regeneration in clinic. This review focuses on the roles of BAs and FXR in liver regeneration and the current underlying molecular mechanisms which contribute to liver regeneration.

  9. Fcγ receptor-mediated inflammation inhibits axon regeneration.

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    Gang Zhang

    Full Text Available Anti-glycan/ganglioside antibodies are the most common immune effectors found in patients with Guillain-Barré Syndrome, which is a peripheral autoimmune neuropathy. We previously reported that disease-relevant anti-glycan autoantibodies inhibited axon regeneration, which echo the clinical association of these antibodies and poor recovery in Guillain-Barré Syndrome. However, the specific molecular and cellular elements involved in this antibody-mediated inhibition of axon regeneration are not previously defined. This study examined the role of Fcγ receptors and macrophages in the antibody-mediated inhibition of axon regeneration. A well characterized antibody passive transfer sciatic nerve crush and transplant models were used to study the anti-ganglioside antibody-mediated inhibition of axon regeneration in wild type and various mutant and transgenic mice with altered expression of specific Fcγ receptors and macrophage/microglia populations. Outcome measures included behavior, electrophysiology, morphometry, immunocytochemistry, quantitative real-time PCR, and western blotting. We demonstrate that the presence of autoantibodies, directed against neuronal/axonal cell surface gangliosides, in the injured mammalian peripheral nerves switch the proregenerative inflammatory environment to growth inhibitory milieu by engaging specific activating Fcγ receptors on recruited monocyte-derived macrophages to cause severe inhibition of axon regeneration. Our data demonstrate that the antibody orchestrated Fcγ receptor-mediated switch in inflammation is one mechanism underlying inhibition of axon regeneration. These findings have clinical implications for nerve repair and recovery in antibody-mediated immune neuropathies. Our results add to the complexity of axon regeneration in injured peripheral and central nervous systems as adverse effects of B cells and autoantibodies on neural injury and repair are increasingly recognized.

  10. Mesenchymal stem cell-mediated functional tooth regeneration in swine.

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    Wataru Sonoyama

    2006-12-01

    Full Text Available Mesenchymal stem cell-mediated tissue regeneration is a promising approach for regenerative medicine for a wide range of applications. Here we report a new population of stem cells isolated from the root apical papilla of human teeth (SCAP, stem cells from apical papilla. Using a minipig model, we transplanted both human SCAP and periodontal ligament stem cells (PDLSCs to generate a root/periodontal complex capable of supporting a porcelain crown, resulting in normal tooth function. This work integrates a stem cell-mediated tissue regeneration strategy, engineered materials for structure, and current dental crown technologies. This hybridized tissue engineering approach led to recovery of tooth strength and appearance.

  11. Regeneration of the liver at different periods of mononuclear infiltration induced by zymosan granules

    International Nuclear Information System (INIS)

    Shcherbakov, V.I.; Komlyagina, T.G.; Mayanskii, D.N.

    1985-01-01

    The aim of this investigation was to discover how the liver,with areas of mononuclear infiltration, developing in response to activation of Kupffer cells (KC) by zymosan granules (ZG), regenerates. In the experiments, an intraperitoneal injection of 1 microCi of 3 H-thymidine/g body weight was given to the mice 1 h before sacrifice. Proliferation of hepatocytes and regeneration of the liver were intensified most when partial resection of the liver (PRL) was performed at the peak of mononuclear infiltration of the liver, namely five days after injection of ZG. The data indicate that not only activated KC, but also areas of mononuclear infiltration potentiate hepatocyte regeneration

  12. Follistatin allows efficient retroviral-mediated gene transfer into rat liver

    International Nuclear Information System (INIS)

    Borgnon, Josephine; Djamouri, Fatima; Lorand, Isabelle; Rico, Virginie Di; Loux, Nathalie; Pages, Jean-Christophe; Franco, Dominique; Capron, Frederique; Weber, Anne

    2005-01-01

    Retroviral vectors are widely used tools for gene therapy. However, in vivo gene transfer is only effective in dividing cells, which, in liver, requires a regenerative stimulus. Follistatin is effective in promoting liver regeneration after 90% and 70% hepatectomy in rats. We studied its efficacy on liver regeneration and retroviral-mediated gene delivery in 50% hepatectomized rats. When human recombinant follistatin was infused into the portal vein immediately after 50% hepatectomy, hepatocyte proliferation was significantly higher than in control 50% hepatectomized rats. A single injection of virus particles administered 23 h after follistatin infusion resulted in more than 20% gene transduction efficiency in hepatocytes compared to 3% in control rats. It is concluded that a single injection of follistatin induces onset of proliferation in 50% hepatectomized rats and allows efficient retroviral-mediated gene transfer to the liver

  13. Putrescine treatment reverses α-tocopherol-induced desynchronization of polyamine and retinoid metabolism during rat liver regeneration

    Directory of Open Access Journals (Sweden)

    Lourdes Sánchez-Sevilla

    2016-10-01

    Full Text Available Abstract Background The pre-treatment with α-tocopherol inhibits progression of rat liver proliferation induced by partial hepatectomy (PH, by decreasing and/or desynchronizing cyclin D1 expression and activation into the nucleus, activation and nuclear translocation of STAT-1 and -3 proteins and altering retinoid metabolism. Interactions between retinoic acid and polyamines have been reported in the PH-induced rat liver regeneration. Therefore, we evaluated the effect of low dosage of α-tocopherol on PH-induced changes in polyamine metabolism. Methods This study evaluated the participation of polyamine synthesis and metabolism during α-tocopherol-induced inhibition of rat liver regeneration. In PH-rats (Wistar treated with α-tocopherol and putrescine, parameters indicative of cell proliferation, lipid peroxidation, ornithine decarboxylase expression (ODC, and polyamine levels, were determined. Results Pre-treatment with α-tocopherol to PH-animals exerted an antioxidant effect, shifting earlier the increased ODC activity and expression, temporally affecting polyamine synthesis and ornithine metabolism. Whereas administration of putrescine induced minor changes in PH-rats, the concomitant treatment actually counteracted most of adverse actions exerted by α-tocopherol on the remnant liver, restituting its proliferative potential, without changing its antioxidant effect. Putrescine administration to these rats was also associated with lower ODC expression and activity in the proliferating liver, but the temporally shifting in the amount of liver polyamines induced by α-tocopherol, was also “synchronized” by the putrescine administration. The latter is supported by the fact that a close relationship was observed between fluctuations of polyamines and retinoids. Conclusions Putrescine counteracted most adverse actions exerted by α-tocopherol on rat liver regeneration, restoring liver proliferative potential and restituting the decreased

  14. Phosphatase of Regenerating Liver-3 Promotes Motility and Metastasis of Mouse Melanoma Cells

    Science.gov (United States)

    Wu, Xiaopeng; Zeng, Hu; Zhang, Xianming; Zhao, Ying; Sha, Haibo; Ge, Xiaomei; Zhang, Minyue; Gao, Xiang; Xu, Qiang

    2004-01-01

    Recent reports suggested that phosphatase of regenerating liver (PRL)-3 might be involved in colorectal carcinoma metastasis with an unknown mechanism. Here we demonstrated that PRL-3 expression was up-regulated in human liver carcinoma compared with normal liver. PRL-3 was also highly expressed in metastatic melanoma B16-BL6 cells but not in its lowly metastatic parental cell line, B16 cells. B16 cells transfected with PRL-3 cDNA displayed morphological transformation from epithelial-like shape to fibroblast-like shape. PRL-3-overexpressed cells showed much higher migratory ability, which could be reversed by specific anti-sense oligodeoxynucleotide and the phosphatase inhibitors sodium orthovanadate or potassium bisperoxo oxovanadate V. Meanwhile, the expression of the catalytically inactive PRL-3 mutations (D72A or C104S) significantly reduced the cell migratory capability. In addition, PRL-3 transfectants demonstrated altered extracellular matrix adhesive property and up-regulated integrin-mediated cell spreading efficiency. Furthermore, we confirmed that PRL-3 could facilitate lung and liver metastasis of B16 cells in an experimental metastasis model in mice, consistent with accelerated proliferation and growth rate both in vitro and in vivo. Together, these observations provide convincing evidence that PRL-3 truly plays a causal role in tumor metastasis. PMID:15161639

  15. UPF2 is a critical regulator of liver development, function and regeneration

    DEFF Research Database (Denmark)

    Thoren, Lina A; Nørgaard, Gitte A; Weischenfeldt, Joachim

    2010-01-01

    regulatory potential of the NMD pathway in mammals will require the functional assessment of NMD in different tissues. METHODOLOGY/PRINCIPAL FINDINGS: Here we use mouse genetics to address the role of UPF2, a core NMD component, in the development, function and regeneration of the liver. We find that loss....... CONCLUSION/SIGNIFICANCE: Collectively, our data demonstrate the critical role of the NMD pathway in liver development, function and regeneration and highlights the importance of NMD for mammalian biology....... of NMD during fetal liver development is incompatible with postnatal life due to failure of terminal differentiation. Moreover, deletion of Upf2 in the adult liver results in hepatosteatosis and disruption of liver homeostasis. Finally, NMD was found to be absolutely required for liver regeneration...

  16. Expression of isgylation related genes in regenerating rat liver

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    Kuklin A. V.

    2015-10-01

    Full Text Available Our recent studies have revealed the early up-regulated expression of interferon alpha (IFNα in the liver, induced by partial hepatectomy. The role of this cytokine of innate immune response in liver regeneration is still controversial. Aim. To analyze expression of canonical interferon-stimulated genes Ube1l, Ube2l6, Trim25, Usp18 and Isg15 during the liver transition from quiescence to proliferation induced by partial hepatectomy, and acute phase response induced by laparotomy. These genes are responsible for posttranslational modification of proteins by ISGylation. The expression of genes encoding TATA binding protein (TBP and 18S rRNA served as indirect general markers of transcriptional and translational activities. Methods. The abundance of investigated RNAs was assessed in total liver RNA by real time RT–qPCR. Results. Partial hepatecomy induced steady upregulation of the Tbp and 18S rRNA genes expression during 12 hours post-surgery and downregulation or no change in expression of ISGylation-related genes during the first 3 hours followed by slight upregulation at 12 hours. The level of Isg15 transcripts was permanently below that of the control during the prereplicative period. Laparotomy induced a continuous downregulation of Tbp and 18S rRNA expression and early (1–3h upregulation of ISGylation–related transcripts followed by a sharp drop at 6 hours and slight increase/decrease at 12 hours. The changes in the abundance of Ifnα and ISGylation-related mRNAs were oppositely directed at each stage of the response to partial hepatectomy and laparotomy. Conclusion. We suggest that the expression of ISGylation-related genes does not depend on the expression of Ifnα gene after both surgeries. The indirect indices of transcription and translation as well as the expression of ISGylation-relaled genes are principally different in response to partial hepatectomy and laparotomy and argue for the high specificity of innate immune response.

  17. Lung Regeneration: Endogenous and Exogenous Stem Cell Mediated Therapeutic Approaches.

    Science.gov (United States)

    Akram, Khondoker M; Patel, Neil; Spiteri, Monica A; Forsyth, Nicholas R

    2016-01-19

    The tissue turnover of unperturbed adult lung is remarkably slow. However, after injury or insult, a specialised group of facultative lung progenitors become activated to replenish damaged tissue through a reparative process called regeneration. Disruption in this process results in healing by fibrosis causing aberrant lung remodelling and organ dysfunction. Post-insult failure of regeneration leads to various incurable lung diseases including chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis. Therefore, identification of true endogenous lung progenitors/stem cells, and their regenerative pathway are crucial for next-generation therapeutic development. Recent studies provide exciting and novel insights into postnatal lung development and post-injury lung regeneration by native lung progenitors. Furthermore, exogenous application of bone marrow stem cells, embryonic stem cells and inducible pluripotent stem cells (iPSC) show evidences of their regenerative capacity in the repair of injured and diseased lungs. With the advent of modern tissue engineering techniques, whole lung regeneration in the lab using de-cellularised tissue scaffold and stem cells is now becoming reality. In this review, we will highlight the advancement of our understanding in lung regeneration and development of stem cell mediated therapeutic strategies in combating incurable lung diseases.

  18. Anti-inflammatory liposomes have no impact on liver regeneration in rats

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    Betina Norman Jepsen

    2015-12-01

    Conclusion: Low dose dexamethasone targeted to Kupffer cells does not affect histological liver cell regeneration after 70% hepatectomy in rats, but reduces the inflammatory response judged by circulating markers of inflammation.

  19. Shear stress upregulates regeneration-related immediate early genes in liver progenitors in 3D ECM-like microenvironments.

    Science.gov (United States)

    Nishii, Kenichiro; Brodin, Erik; Renshaw, Taylor; Weesner, Rachael; Moran, Emma; Soker, Shay; Sparks, Jessica L

    2018-05-01

    The role of fluid stresses in activating the hepatic stem/progenitor cell regenerative response is not well understood. This study hypothesized that immediate early genes (IEGs) with known links to liver regeneration will be upregulated in liver progenitor cells (LPCs) exposed to in vitro shear stresses on the order of those produced from elevated interstitial flow after partial hepatectomy. The objectives were: (1) to develop a shear flow chamber for application of fluid stress to LPCs in 3D culture; and (2) to determine the effects of fluid stress on IEG expression in LPCs. Two hours of shear stress exposure at ∼4 dyn/cm 2 was applied to LPCs embedded individually or as 3D spheroids within a hyaluronic acid/collagen I hydrogel. Results were compared against static controls. Quantitative reverse transcriptase polymerase chain reaction was used to evaluate the effect of experimental treatments on gene expression. Twenty-nine genes were analyzed, including IEGs and other genes linked to liver regeneration. Four IEGs (CFOS, IP10, MKP1, ALB) and three other regeneration-related genes (WNT, VEGF, EpCAM) were significantly upregulated in LPCs in response to fluid mechanical stress. LPCs maintained an early to intermediate stage of differentiation in spheroid culture in the absence of the hydrogel, and addition of the gel initiated cholangiocyte differentiation programs which were abrogated by the onset of flow. Collectively the flow-upregulated genes fit the pattern of an LPC-mediated proliferative/regenerative response. These results suggest that fluid stresses are potentially important regulators of the LPC-mediated regeneration response in liver. © 2017 Wiley Periodicals, Inc.

  20. Review fantastic medical implications of 3D-printing in liver surgeries, liver regeneration, liver transplantation and drug hepatotoxicity testing: A review.

    Science.gov (United States)

    Wang, Jing-Zhang; Xiong, Nan-Yan; Zhao, Li-Zhen; Hu, Jin-Tian; Kong, De-Cheng; Yuan, Jiang-Yong

    2018-06-07

    The epidemiological trend in liver diseases becomes more serious worldwide. Several recent articles published by International Journal of Surgery in 2018 particularly emphasized the encouraging clinical benefits of hepatectomy, liver regeneration and liver transplantation, however, there are still many technical bottlenecks underlying these therapeutic approaches. Remarkably, a few preliminary studies have shown some clues to the role of three-dimensional (3D) printing in improving traditional therapy for liver diseases. Here, we concisely elucidated the curative applications of 3D-printing (no cells) and 3D Bio-printing (with hepatic cells), such as 3D-printed patient-specific liver models and devices for medical education, surgical simulation, hepatectomy and liver transplantation, 3D Bio-printed hepatic constructs for liver regeneration and artificial liver, 3D-printed liver tissues for evaluating drug's hepatotoxicity, and so on. Briefly, 3D-printed liver models and bioactive tissues may facilitate a lot of key steps to cure liver disorders, predictably bringing promising clinical benefits. This work further provides novel insights into facilitating treatment of hepatic carcinoma, promoting liver regeneration both in vivo and in vitro, expanding transplantable liver resources, maximizing therapeutic efficacy as well as minimizing surgical complications, medical hepatotoxicity, operational time, economic costs, etc. Copyright © 2018. Published by Elsevier Ltd.

  1. HIF-1{alpha} is necessary to support gluconeogenesis during liver regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Tajima, Toshihide [Department of Obstetrics and Gynecology, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Goda, Nobuhito, E-mail: goda@waseda.jp [Department of Life Science and Medical Bio-Science, School of Advanced Science and Engineering, Waseda University, TWIns 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480 (Japan); Fujiki, Natsuko; Hishiki, Takako; Nishiyama, Yasumasa [Department of Biochemistry and Integrative Medical Biology, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Senoo-Matsuda, Nanami [Department of Life Science and Medical Bio-Science, School of Advanced Science and Engineering, Waseda University, TWIns 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480 (Japan); Shimazu, Motohide [Department of Surgery, Tokyo Medical University Hachioji Medical Center, 1163 Tatemachi, Hachioji, Tokyo 193-0998 (Japan); Soga, Tomoyoshi [The Institute for Advanced Biosciences, Keio University, Tsuruoka City, Yamagata 997-0052 (Japan); Yoshimura, Yasunori [Department of Obstetrics and Gynecology, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Johnson, Randall S. [Molecular Biology Section, Division of Biology, University of California, San Diego, La Jolla, CA 92093 (United States); Suematsu, Makoto [Department of Biochemistry and Integrative Medical Biology, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan)

    2009-10-02

    Coordinated recovery of hepatic glucose metabolism is prerequisite for normal liver regeneration. To examine roles of hypoxia inducible factor-1{alpha} (HIF-1{alpha}) for hepatic glucose homeostasis during the reparative process, we inactivated the gene in hepatocytes in vivo. Following partial hepatectomy (PH), recovery of residual liver weight was initially retarded in the mutant mice by down-regulation of hepatocyte proliferation, but occurred comparably between the mutant and control mice at 72 h after PH. At this time point, the mutant mice showed lowered blood glucose levels with enhanced accumulation of glycogen in the liver. The mutant mice exhibited impairment of hepatic gluconeogenesis as assessed by alanine tolerance test. This appeared to result from reduced expression of PGK-1 and PEPCK since 3-PG, PEP and malate were accumulated to greater extents in the regenerated liver. In conclusion, these findings provide evidence for roles of HIF-1{alpha} in the regulation of gluconeogenesis under liver regeneration.

  2. HIF-1α is necessary to support gluconeogenesis during liver regeneration

    International Nuclear Information System (INIS)

    Tajima, Toshihide; Goda, Nobuhito; Fujiki, Natsuko; Hishiki, Takako; Nishiyama, Yasumasa; Senoo-Matsuda, Nanami; Shimazu, Motohide; Soga, Tomoyoshi; Yoshimura, Yasunori; Johnson, Randall S.; Suematsu, Makoto

    2009-01-01

    Coordinated recovery of hepatic glucose metabolism is prerequisite for normal liver regeneration. To examine roles of hypoxia inducible factor-1α (HIF-1α) for hepatic glucose homeostasis during the reparative process, we inactivated the gene in hepatocytes in vivo. Following partial hepatectomy (PH), recovery of residual liver weight was initially retarded in the mutant mice by down-regulation of hepatocyte proliferation, but occurred comparably between the mutant and control mice at 72 h after PH. At this time point, the mutant mice showed lowered blood glucose levels with enhanced accumulation of glycogen in the liver. The mutant mice exhibited impairment of hepatic gluconeogenesis as assessed by alanine tolerance test. This appeared to result from reduced expression of PGK-1 and PEPCK since 3-PG, PEP and malate were accumulated to greater extents in the regenerated liver. In conclusion, these findings provide evidence for roles of HIF-1α in the regulation of gluconeogenesis under liver regeneration.

  3. Metallothionein expression during liver regeneration after partial hepatectomy in cadmium-pretreated rats

    Energy Technology Data Exchange (ETDEWEB)

    Margeli, A.P. (Dept. of Forensic Medicine and Toxicology, School of Medicine, Univ. of Athens (Greece)); Theocharis, S.E. (Dept. of Forensic Medicine and Toxicology, School of Medicine, Univ. of Athens (Greece)); Yannacou, N.N. (Dept. of Forensic Medicine and Toxicology, School of Medicine, Univ. of Athens (Greece)); Spiliopoulou, C. (Dept. of Forensic Medicine and Toxicology, School of Medicine, Univ. of Athens (Greece)); Koutselinis, A. (Dept. of Forensic Medicine and Toxicology, School of Medicine, Univ. of Athens (Greece))

    1994-10-01

    Metallothionein is a low molecular mass protein inducible mainly by heavy metals, having high affinity for binding cadmium, zinc and copper. In the present study we investigated the expression of metallothionein in regenerating liver, at different time intervals, in cadmium pretreated partially hepatectomized rats. Liver metallothionein is highly expressed during regeneration induced by partial hepatectomy in rats, providing zinc within the rapidly growing tissue. Cadmium pretreatment caused inhibition of the first peak of liver regeneration, while metallothionein expression was markedly more prominent in the liver residues of cadmium-pretreated rats. These results demonstrate that although metallothionein able to bind temporarily metal ions as zinc and cadmium has been highly expressed, the liver regenerative process was inhibited possibly due to the effects of cadmium on other pivotal events necessary to the DNA replication. (orig.)

  4. Effect of the Human Amniotic Membrane on Liver Regeneration in Rats

    Directory of Open Access Journals (Sweden)

    Mesut Sipahi

    2015-01-01

    Full Text Available Introduction. Operations are performed for broader liver surgery indications for a better understanding of hepatic anatomy/physiology and developments in operation technology. Surgery can cure some patients with liver metastasis of some tumors. Nevertheless, postoperative liver failure is the most feared complication causing mortality in patients who have undergone excision of a large liver mass. The human amniotic membrane has regenerative effects. Thus, we investigated the effects of the human amniotic membrane on regeneration of the resected liver. Methods. Twenty female Wistar albino rats were divided into control and experimental groups and underwent a 70% hepatectomy. The human amniotic membrane was placed over the residual liver in the experimental group. Relative liver weight, histopathological features, and biochemical parameters were assessed on postoperative day 3. Results. Total protein and albumin levels were significantly lower in the experimental group than in the control group. No difference in relative liver weight was observed between the groups. Hepatocyte mitotic count was significantly higher in the experimental group than in the control group. Hepatic steatosis was detected in the experimental group. Conclusion. Applying the amniotic membrane to residual liver adversely affected liver regeneration. However, mesenchymal stem cell research has the potential to accelerate liver regeneration investigations.

  5. Interleukin-1 inhibition facilitates recovery from liver injury and promotes regeneration of hepatocytes in alcoholic hepatitis in mice.

    Science.gov (United States)

    Iracheta-Vellve, Arvin; Petrasek, Jan; Gyogyosi, Benedek; Bala, Shashi; Csak, Timea; Kodys, Karen; Szabo, Gyongyi

    2017-07-01

    Inflammation and impaired hepatocyte regeneration contribute to liver failure in alcoholic hepatitis (AH). Interleukin (IL)-1 is a key inflammatory cytokine in the pathobiology of AH. The role of IL-1 in liver regeneration in the recovery phase of alcohol-induced liver injury is unknown. In this study, we tested IL-1 receptor antagonist to block IL-1 signalling in a mouse model of acute-on-chronic liver injury on liver inflammation and hepatocyte regeneration in AH. We observed that inhibition of IL-1 signalling decreased liver inflammation and neutrophil infiltration, and resulted in enhanced regeneration of hepatocytes and increased rate of recovery from liver injury in AH. Our novel findings suggest that IL-1 drives sustained liver inflammation and impaired hepatocyte regeneration even after cessation of ethanol exposure. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Mechanism of impaired regeneration of fatty liver in mouse partial hepatectomy model.

    Science.gov (United States)

    Murata, Hiroshi; Yagi, Takahito; Iwagaki, Hiromi; Ogino, Tetsuya; Sadamori, Hiroshi; Matsukawa, Hiroyoshi; Umeda, Yuzoh; Haga, Sanae; Takaka, Noriaki; Ozaki, Michitaka

    2007-12-01

    The mechanism of injury in steatotic liver under pathological conditions been extensively examined. However, the mechanism of an impaired regeneration is still not well understood. The aim of this study was to analyze the mechanism of impaired regeneration of steatotic liver after partial hepatectomy (PH). db/db fatty mice and lean littermates were used for the experiments. Following 70% PH, the survival rate and recovery of liver mass were examined. Liver tissue was histologically examined and analyzed by western blotting and RT-PCR. Of 35 db/db mice, 25 died within 48 h of PH, while all of the control mice survived. Liver regeneration of surviving db/db mice was largely impaired. In db/db mice, mitosis of hepatocytes after PH was disturbed, even though proliferating cell nuclear antigen (PCNA) expression (G1 to S phase marker) in hepatocytes was equally observed in both mice groups. Interestingly, phosphorylation of Cdc2 in db/db mice was suppressed by reduced expression of Wee1 and Myt1, which phosphorylate Cdc2 in S to G2 phase. In steatotic liver, cell-cycle-related proliferative disorders occurred at mid-S phase after PCNA expression. Reduced expression of Wee1 and Myt1 kinases may therefore maintain Cdc2 in an unphosphorylated state and block cell cycle progression in mid-S phase. These kinases may be critical factors involved in the impaired liver regeneration in fatty liver.

  7. Liver regeneration signature in hepatitis B virus (HBV-associated acute liver failure identified by gene expression profiling.

    Directory of Open Access Journals (Sweden)

    Oriel Nissim

    Full Text Available The liver has inherent regenerative capacity via mitotic division of mature hepatocytes or, when the hepatic loss is massive or hepatocyte proliferation is impaired, through activation of hepatic stem/progenitor cells (HSPC. The dramatic clinical course of acute liver failure (ALF has posed major limitations to investigating the molecular mechanisms of liver regeneration and the role of HSPC in this setting. We investigated the molecular mechanisms of liver regeneration in 4 patients who underwent liver transplantation for hepatitis B virus (HBV-associated ALF.Gene expression profiling of 17 liver specimens from the 4 ALF cases and individual specimens from 10 liver donors documented a distinct gene signature for ALF. However, unsupervised multidimensional scaling and hierarchical clustering identified two clusters of ALF that segregated according to histopathological severity massive hepatic necrosis (MHN; 2 patients and submassive hepatic necrosis (SHN; 2 patients. We found that ALF is characterized by a strong HSPC gene signature, along with ductular reaction, both of which are more prominent in MHN. Interestingly, no evidence of further lineage differentiation was seen in MHN, whereas in SHN we detected cells with hepatocyte-like morphology. Strikingly, ALF was associated with a strong tumorigenesis gene signature. MHN had the greatest upregulation of stem cell genes (EpCAM, CK19, CK7, whereas the most up-regulated genes in SHN were related to cellular growth and proliferation. The extent of liver necrosis correlated with an overriding fibrogenesis gene signature, reflecting the wound-healing process.Our data provide evidence for a distinct gene signature in HBV-associated ALF whose intensity is directly correlated with the histopathological severity. HSPC activation and fibrogenesis positively correlated with the extent of liver necrosis. Moreover, we detected a tumorigenesis gene signature in ALF, emphasizing the close relationship between

  8. Monocytes with angiogenic potential are selectively induced by liver resection and accumulate near the site of liver regeneration.

    Science.gov (United States)

    Schauer, Dominic; Starlinger, Patrick; Zajc, Philipp; Alidzanovic, Lejla; Maier, Thomas; Buchberger, Elisabeth; Pop, Lorand; Gruenberger, Birgit; Gruenberger, Thomas; Brostjan, Christine

    2014-10-30

    Monocytes reportedly contribute to liver regeneration. Three subsets have been identified to date: classical, intermediate, non-classical monocytes. The intermediate population and a subtype expressing TIE2 (TEMs) were suggested to promote angiogenesis. In a clinical setting, we investigated which monocyte subsets are regulated after liver resection and correlate with postoperative liver function. In 38 patients monocyte subsets were evaluated in blood and subhepatic wound fluid by flow cytometry before and 1-3 days after resection of colorectal liver metastases. The monocyte-regulating cytokines macrophage colony stimulating factor (M-CSF), transforming growth factor beta 1 (TGFβ1), and angiopoietin 2 (ANG-2) were measured in patient plasma by ELISA. C-reactive protein (CRP) and liver function parameters were retrieved from routine hospital analyses. On post-operative day (POD) 1 blood monocytes shifted to significantly elevated levels of intermediate monocytes. In wound fluid, a delayed surge in intermediate monocytes was detected by POD 3. Furthermore, TEMs were highly enriched in wound fluid as compared to circulation. CRP and M-CSF levels were substantially increased in patient blood after surgery and correlated significantly with the frequency of intermediate monocytes. In addition, liver function parameters showed a significant association with intermediate monocyte levels on POD 3. The reportedly pro-angiogenic subsets of monocytes are selectively increased upon liver resection and accumulate next to the site of liver regeneration. As previously proposed by in vitro experiments, the release of CRP and M-CSF may trigger the induction of intermediate monocytes. The correlation with liver parameters points to a functional involvement of these monocyte populations in liver regeneration which warrants further investigation.

  9. The Effect of Elephantopus scaber L. on Liver Regeneration after Partial Hepatectomy

    Directory of Open Access Journals (Sweden)

    Chin-Chuan Tsai

    2013-01-01

    Full Text Available Liver regeneration after partial hepatectomy (PHx is a physiological response for maintaining homeostasis. The aim of this study is to investigate effects of Elephantopus scaber L.- (ESL- induced liver regeneration on growth factors (HGF and IGF-1, cell cycle regulation, and apoptosis suppressed. In this study, we fed five Chinese medicinal herbs (1 g/kg/day, Codonopsis pilosula (CP, Dangshen, Salvia miltiorrhiza Bunge (SMB, Danshen,, Bupleurum kasi (BK, Chaihu, Elephantopus scaber L. (ESL, Teng-Khia-U, and Silymarin (Sm, 25 mg/kg for 7 days to male Spraue-Dawley rats. Then surgical 2/3 PHx was conducted and liver regeneration mechanisms were estimated on the following 24 hrs and 72 hrs. The activities of growth factors (HGF and IGF-I and cell cycle proteins were measured by Western blot and RT-PCR. Histological analysis and apoptosis were detected by H&E stain and TUNEL. The results showed that extraction of Elephantopus scaber L. (ESL and Silymarin (Sm, positive control were increased protein expression levels of HGF and IGF-1 which leads into cell cycle. These results suggest that the ESL plays a crucial role in cell cycle-induced liver regeneration and apoptosis. These results suggested that the ESL plays a crucial role in cell cycle-induced liver regeneration and suppressed hepatocytes apoptosis.

  10. Mitochondrial DNA Unwinding Enzyme Required for Liver Regeneration | Center for Cancer Research

    Science.gov (United States)

    The liver has an exceptional capacity to proliferate. This ability allows the liver to regenerate its mass after partial surgical removal or injury and is the key to successful partial liver transplants. Liver cells, called hepatocytes, are packed with mitochondria, and regulating mitochondrial DNA (mtDNA) copy number is crucial to mitochondrial function, including energy production, during proliferation. Yves Pommier, M.D., Ph.D., of CCR’s Developmental Therapeutics Branch, and his colleagues recently showed that the vertebrate mitochondrial topoisomerase, Top1mt, was critical in maintaining mitochondrial function in the heart after doxorubicin-induced damage. The group wondered whether Top1mt might play a similar role in liver regeneration.

  11. Thrombospondin-1 is a novel negative regulator of liver regeneration after partial hepatectomy through transforming growth factor-beta1 activation in mice.

    Science.gov (United States)

    Hayashi, Hiromitsu; Sakai, Keiko; Baba, Hideo; Sakai, Takao

    2012-05-01

    The matricellular protein, thrombospondin-1 (TSP-1), is prominently expressed during tissue repair. TSP-1 binds to matrix components, proteases, cytokines, and growth factors and activates intracellular signals through its multiple domains. TSP-1 converts latent transforming growth factor-beta1 (TGF-β1) complexes into their biologically active form. TGF-β plays significant roles in cell-cycle regulation, modulation of differentiation, and induction of apoptosis. Although TGF-β1 is a major inhibitor of proliferation in cultured hepatocytes, the functional requirement of TGF-β1 during liver regeneration remains to be defined in vivo. We generated a TSP-1-deficient mouse model of a partial hepatectomy (PH) and explored TSP-1 induction, progression of liver regeneration, and TGF-β-mediated signaling during the repair process after hepatectomy. We show here that TSP-1-mediated TGF-β1 activation plays an important role in suppressing hepatocyte proliferation. TSP-1 expression was induced in endothelial cells (ECs) as an immediate early gene in response to PH. TSP-1 deficiency resulted in significantly reduced TGF-β/Smad signaling and accelerated hepatocyte proliferation through down-regulation of p21 protein expression. TSP-1 induced in ECs by reactive oxygen species (ROS) modulated TGF-β/Smad signaling and proliferation in hepatocytes in vitro, suggesting that the immediately and transiently produced ROS in the regenerating liver were the responsible factor for TSP-1 induction. We have identified TSP-1 as an inhibitory element in regulating liver regeneration by TGF-β1 activation. Our work defines TSP-1 as a novel immediate early gene that could be a potential therapeutic target to accelerate liver regeneration. Copyright © 2011 American Association for the Study of Liver Diseases.

  12. Mesenchymal Stem Cells Enhance Liver Regeneration via Improving Lipid Accumulation and Hippo Signaling

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    Yang Liu

    2018-01-01

    Full Text Available The liver has the potential to regenerate after injury. It is a challenge to improve liver regeneration (LR after liver resection in clinical practice. Bone morrow-derived mesenchymal stem cells (MSCs have shown to have a role in various liver diseases. To explore the effects of MSCs on LR, we established a model of 70% partial hepatectomy (PHx. Results revealed that infusion of MSCs could improve LR through enhancing cell proliferation and cell growth during the first 2 days after PHx, and MSCs could also restore liver synthesis function. Infusion of MSCs also improved liver lipid accumulation partly via mechanistic target of rapamycin (mTOR signaling and enhanced lipid β-oxidation support energy for LR. Rapamycin-induced inhibition of mTOR decreased liver lipid accumulation at 24 h after PHx, leading to impaired LR. And after infusion of MSCs, a proinflammatory environment formed in the liver, evidenced by increased expression of IL-6 and IL-1β, and thus the STAT3 and Hippo-YAP pathways were activated to improve cell proliferation. Our results demonstrated the function of MSCs on LR after PHx and provided new evidence for stem cell therapy of liver diseases.

  13. Implications of microbiota and bile acid in liver injury and regeneration.

    Science.gov (United States)

    Liu, Hui-Xin; Keane, Ryan; Sheng, Lili; Wan, Yu-Jui Yvonne

    2015-12-01

    Studies examining the mechanisms by which the liver incurs injury and then regenerates usually focus on factors and pathways directly within the liver, neglecting the signaling derived from the gut-liver axis. The intestinal content is rich in microorganisms as well as metabolites generated from both the host and colonizing bacteria. Through the gut-liver axis, this complex "soup" exerts an immense impact on liver integrity and function. This review article summarizes data published in the past 30 years demonstrating the signaling derived from the gut-liver axis in relation to liver injury and regeneration. Due to the intricate networks of implicated pathways as well as scarcity of available mechanistic data, it seems that nutrigenomic, metabolomics, and microbiota profiling approaches are warranted to provide a better understanding regarding the interplay and impact between nutrition, bacteria, and host response in influencing liver function and healing. Therefore elucidating the possible molecular mechanisms that link microbiota alteration to host physiological response and vice versa. Published by Elsevier B.V.

  14. Comparative retention of fission fragment 147Pm in regenerated and fetal liver on induction of chromosome aberrations in these cells

    International Nuclear Information System (INIS)

    Zhu Shoupeng; Zheng Siying; Wang Liuyi; Yang Shujin

    1989-01-01

    The purpose of the present study is to ascertain comparative retention of fission fragment 147 Pm in regenerated and fetal liver on induction of chromosome aberrations in these cells. The results indicated that retention of 147 Pm in regenerated liver was about 700 times than in fetal liver. The cumulative absorption dose in regenerated liver was about 2.87 Gy, while in fetal liver-only 0.004 Gy. Under the same conditions, the incidence rate of chromosome aberrations in regenerated liver cells induced by 147 Pm was 50.2%, and in fetal liver cells-about 28.3%. It should be concluded that the radiosensitivity to 147 Pm was not uniform among the regenerated and fetal liver cells. The study suggested that fetal liver cells show to be more radiosensitive to 147 Pm than regenerated liver cells. Among the type of aberrations in both cells induced by 147 Pm, chromatid breakages were predominant, accompanied with a few chromosome breakages

  15. Hepatocyte-specific deletion of Cdc42 results in delayed liver regeneration after partial hepatectomy in mice

    DEFF Research Database (Denmark)

    Yuan, Haixin; Zhang, Hong; Wu, Xunwei

    2009-01-01

    Cdc42, a member of the Rho guanosine triphosphatase (GTPase) family, plays important roles in the regulation of the cytoskeleton, cell proliferation, cell polarity, and cellular transport, but little is known about its specific function in mammalian liver. We investigated the function of Cdc42...... in regulating liver regeneration. Using a mouse model with liver-specific knockout of Cdc42 (Cdc42LK), we studied liver regeneration after partial hepatectomy. Histological analysis, immunostaining, and western blot analysis were performed to characterize Cdc42LK livers and to explore the role of Cdc42 in liver...... regeneration. In control mouse livers, Cdc42 became activated between 3 and 24 hours after partial hepatectomy. Loss of Cdc42 led to a significant delay of liver recovery after partial hepatectomy, which was associated with reduced and delayed DNA synthesis indicated by 5-bromo-2'-deoxyuridine staining...

  16. Bone morphogenetic protein-2 is a negative regulator of hepatocyte proliferation downregulated in the regenerating liver

    NARCIS (Netherlands)

    Xu, Cui-Ping; Ji, Wen-Min; van den Brink, Gijs R.; Peppelenbosch, Maikel P.

    2006-01-01

    To characterize the expression and dynamic changes of bone morphogenetic protein (BMP)-2 in hepatocytes in the regenerating liver in rats after partial hepatectomy (PH), and examine the effects of BMP-2 on proliferation of human Huh7 hepatoma cells. Fifty-four adult male Wistar rats were randomly

  17. Bone morphogenetic protein-2 is a negative regulator of hepatocyte proliferation downregulated in the regenerating liver

    NARCIS (Netherlands)

    Xu, Cui-Ping; Ji, Wen-Min; van den Brink, Gijs R.; Peppelenbosch, Maikel P.

    2006-01-01

    AIM: To characterize the expression and dynamic changes of bone morphogenetic protein (BMP)-2 in hepatocytes in the regenerating liver in rats after partial hepatectomy (PH), and examine the effects of BMP-2 on proliferation of human Huh7 hepatoma cells. METHODS: Fifty-four adult male Wistar rats

  18. Interleukin-1 receptor antagonist modulates the early phase of liver regeneration after partial hepatectomy in mice.

    Directory of Open Access Journals (Sweden)

    Antonino Sgroi

    Full Text Available BACKGROUND: Cytokine administration is a potential therapy for acute liver failure by reducing inflammatory responses and favour hepatocyte regeneration. The aim of this study was to evaluate the role of interleukin-1 receptor antagonist (IL-1ra during liver regeneration and to study the effect of a recombinant human IL-1ra on liver regeneration. METHODS: We performed 70%-hepatectomy in wild type (WT mice, IL-1ra knock-out (KO mice and in WT mice treated by anakinra. We analyzed liver regeneration at regular intervals by measuring the blood levels of cytokines, the hepatocyte proliferation by bromodeoxyuridin (BrdU incorporation, proliferating cell nuclear antigen (PCNA and Cyclin D1 expression. The effect of anakinra on hepatocyte proliferation was also tested in vitro using human hepatocytes. RESULTS: At 24h and at 48 h after hepatectomy, IL-1ra KO mice had significantly higher levels of pro-inflammatory cytokines (IL-6, IL-1β and MCP-1 and a reduced and delayed hepatocyte proliferation measured by BrdU incorporation, PCNA and Cyclin D1 protein levels, when compared to WT mice. IGFBP-1 and C/EBPβ expression was significantly decreased in IL-1ra KO compared to WT mice. WT mice treated with anakinra showed significantly decreased levels of IL-6 and significantly higher hepatocyte proliferation at 24h compared to untreated WT mice. In vitro, primary human hepatocytes treated with anakinra showed significantly higher proliferation at 24h compared to hepatocytes without treatment. CONCLUSION: IL1ra modulates the early phase of liver regeneration by decreasing the inflammatory stress and accelerating the entry of hepatocytes in proliferation. IL1ra might be a therapeutic target to improve hepatocyte proliferation.

  19. Replicative stress and alterations in cell cycle checkpoint controls following acetaminophen hepatotoxicity restrict liver regeneration.

    Science.gov (United States)

    Viswanathan, Preeti; Sharma, Yogeshwar; Gupta, Priya; Gupta, Sanjeev

    2018-03-05

    Acetaminophen hepatotoxicity is a leading cause of hepatic failure with impairments in liver regeneration producing significant mortality. Multiple intracellular events, including oxidative stress, mitochondrial damage, inflammation, etc., signify acetaminophen toxicity, although how these may alter cell cycle controls has been unknown and was studied for its significance in liver regeneration. Assays were performed in HuH-7 human hepatocellular carcinoma cells, primary human hepatocytes and tissue samples from people with acetaminophen-induced acute liver failure. Cellular oxidative stress, DNA damage and cell proliferation events were investigated by mitochondrial membrane potential assays, flow cytometry, fluorescence staining, comet assays and spotted arrays for protein expression after acetaminophen exposures. In experimental groups with acetaminophen toxicity, impaired mitochondrial viability and substantial DNA damage were observed with rapid loss of cells in S and G2/M and cell cycle restrictions or even exit in the remainder. This resulted from altered expression of the DNA damage regulator, ATM and downstream transducers, which imposed G1/S checkpoint arrest, delayed entry into S and restricted G2 transit. Tissues from people with acute liver failure confirmed hepatic DNA damage and cell cycle-related lesions, including restrictions of hepatocytes in aneuploid states. Remarkably, treatment of cells with a cytoprotective cytokine reversed acetaminophen-induced restrictions to restore cycling. Cell cycle lesions following mitochondrial and DNA damage led to failure of hepatic regeneration in acetaminophen toxicity but their reversibility offers molecular targets for treating acute liver failure. © 2018 John Wiley & Sons Ltd.

  20. The Role of Platelets in Liver Inflammation and Regeneration

    NARCIS (Netherlands)

    Lisman, Ton; Porte, Robert J.

    Platelets play a pivotal role in thrombosis and hemostasis, but an increasing variety of extra-hemostatic functions of platelets are being recognized. This review summarizes recent advances in the understanding of the role of platelets in various pathologies involving the liver. In

  1. The regulation of cytoskeletal and liver-specific gene expression during liver regeneration and primary hepatocyte culture

    International Nuclear Information System (INIS)

    Robinson, G.S.

    1989-01-01

    The focus of this dissertation is to determine what role(s) the extracellular matrix and expression of certain cytoskeletal genes play in the regulation of hepatocyte growth and the maintenance of a differential state. The expression of several cytoskeletal and liver-specific genes was examined during liver regeneration and in hepatocyte cultures maintained in a hormonally-defined, serum-free medium and plated on two different matrices: rat tail collagen and the EHS matrix. During liver regeneration and in hepatocytes cultured on rat tail collagen, there was a dramatic increase in tubulin mRNA levels coincident with but not linked to DNA synthesis. The message levels for other cytoskeletal genes similarly increased, while a decrease was observed in the mRNA levels of the liver-specific genes, serum albumin and alpha 1 inhibitor III. Hepatocytes cultured on the EHS matrix resulted in the maintenance of low levels of cytoskeletal gene expression and high levels of liver-specific gene expression, similar to that observed in the normal liver. Results from subcellar fractionation and two-dimensional gel electrophoresis of 35 S-labelled proteins paralleled the results seen at the mRNA level. Preliminary work suggests that microtubule organization may play a role in the expression of the liver-specific genes which encode secreted proteins. These studies, which compare hepatocytes cultured on collagen or the EHS matrix gel, reveal that both cell-cell and cell-matrix interactions play a major role in the maintenance of the differential phenotype in hepatocytes

  2. Effect of cadmium pretreatment on liver regeneration after partial hepatectomy in rats

    International Nuclear Information System (INIS)

    Margeli, A.; Theocharis, S.; Skaltsas, S.; Skopelitou, A.; Kittas, C.; Mykoniatis, M.; Varonos, D.

    1994-01-01

    In this study we examined the effect of cadmium pretreatment, administered 24 h before partial hepatectomy, on the liver regenerative process in rats, at different time intervals. The rate of 3 H thymidine incorporation into hepatic DNA and the activity of the enzyme thymidine kinase were used as indices of liver proliferative capacity. Thymidine kinase, the rate-determining enzyme of DNA biosynthesis, was suppressed during the first hours following partial hepatectomy in the liver of cadmium pretreated animals. DNA biosynthesis was also strongly decreased in cadmium pretreated animals, by delaying the first peak of liver regeneration, compared with the partially hepatectomized ones. Biochemical parameters, mitotic index and proliferating cell nuclear antigen staining were also coestimated. The above data suggest that cadmium pretreatment suppressed the hepatic regenerative process, probably due to the inhibition of thymidine kinase. (orig./MG)

  3. Impaired liver regeneration is associated with reduced cyclin B1 in natural killer T cell-deficient mice.

    Science.gov (United States)

    Ben Ya'acov, Ami; Meir, Hadar; Zolotaryova, Lydia; Ilan, Yaron; Shteyer, Eyal

    2017-03-23

    It has been shown that the proportion of natural killer T cells is markedly elevated during liver regeneration and their activation under different conditions can modulate this process. As natural killer T cells and liver injury are central in liver regeneration, elucidating their role is important. The aim of the current study is to explore the role of natural killer T cells in impaired liver regeneration. Concanvalin A was injected 4 days before partial hepatectomy to natural killer T cells- deficient mice or to anti CD1d1-treated mice. Ki-67 and proliferating cell nuclear antigen were used to measure hepatocytes proliferation. Expression of hepatic cyclin B1 and proliferating cell nuclear antigen were evaluated by Western Blot and liver injury was assessed by ALT and histology. Natural killer T cells- deficient or mice injected with anti CD1d antibodies exhibited reduced liver regeneration. These mice were considerably resistant to ConA-induced liver injury. In the absence of NKT cells hepatic proliferating cell nuclear antigen and cyclin B1 decreased in mice injected with Concanvalin A before partial hepatectomy. This was accompanied with reduced serum interleukin-6 levels. Natural killer T cells play an important role in liver regeneration, which is associated with cyclin B1 and interleukin-6.

  4. Human Adipose Tissue Derived Stem Cells Promote Liver Regeneration in a Rat Model of Toxic Injury

    Directory of Open Access Journals (Sweden)

    Eva Koellensperger

    2013-01-01

    Full Text Available In the light of the persisting lack of donor organs and the risks of allotransplantations, the possibility of liver regeneration with autologous stem cells from adipose tissue (ADSC is an intriguing alternative. Using a model of a toxic liver damage in Sprague Dawley rats, generated by repetitive intraperitoneal application of retrorsine and allyl alcohol, the ability of human ADSC to support the restoration of liver function was investigated. A two-thirds hepatectomy was performed, and human ADSC were injected into one remaining liver lobe in group 1 (n = 20. Injection of cell culture medium performed in group 2 (n = 20 served as control. Cyclosporine was applied to achieve immunotolerance. Blood samples were drawn weekly after surgery to determine liver-correlated blood values. Six and twelve weeks after surgery, animals were sacrificed and histological sections were analyzed. ADSC significantly raised postoperative albumin (P < 0.017, total protein (P < 0.031, glutamic oxaloacetic transaminase (P < 0.001, and lactate dehydrogenase (P < 0.04 levels compared to injection of cell culture medium alone. Transplanted cells could be found up to twelve weeks after surgery in histological sections. This study points towards ADSC being a promising alternative to hepatocyte or liver organ transplantation in patients with severe liver failure.

  5. Administration of multipotent mesenchymal stromal cells restores liver regeneration and improves liver function in obese mice with hepatic steatosis after partial hepatectomy.

    Science.gov (United States)

    Ezquer, Fernando; Bahamonde, Javiera; Huang, Ya-Lin; Ezquer, Marcelo

    2017-01-28

    The liver has the remarkable capacity to regenerate in order to compensate for lost or damaged hepatic tissue. However, pre-existing pathological abnormalities, such as hepatic steatosis (HS), inhibits the endogenous regenerative process, becoming an obstacle for liver surgery and living donor transplantation. Recent evidence indicates that multipotent mesenchymal stromal cells (MSCs) administration can improve hepatic function and increase the potential for liver regeneration in patients with liver damage. Since HS is the most common form of chronic hepatic illness, in this study we evaluated the role of MSCs in liver regeneration in an animal model of severe HS with impaired liver regeneration. C57BL/6 mice were fed with a regular diet (normal mice) or with a high-fat diet (obese mice) to induce HS. After 30 weeks of diet exposure, 70% hepatectomy (Hpx) was performed and normal and obese mice were divided into two groups that received 5 × 10 5 MSCs or vehicle via the tail vein immediately after Hpx. We confirmed a significant inhibition of hepatic regeneration when liver steatosis was present, while the hepatic regenerative response was promoted by infusion of MSCs. Specifically, MSC administration improved the hepatocyte proliferative response, PCNA-labeling index, DNA synthesis, liver function, and also reduced the number of apoptotic hepatocytes. These effects may be associated to the paracrine secretion of trophic factors by MSCs and the hepatic upregulation of key cytokines and growth factors relevant for cell proliferation, which ultimately improves the survival rate of the mice. MSCs represent a promising therapeutic strategy to improve liver regeneration in patients with HS as well as for increasing the number of donor organs available for transplantation.

  6. Restoration of CpG Methylation in The Egf Promoter Region during Rat Liver Regeneration

    Science.gov (United States)

    Deming, Li; Ziwei, Li; Xueqiang, Guo; Cunshuan, Xu

    2015-01-01

    Epidermal growth factor (EGF) is an important factor for healing after tissue damage in diverse experimental models. It plays an important role in liver regeneration (LR). The objective of this experiment is to investigate the methylation variation of 10 CpG sites in the Egf promoter region and their relevance to Egf expression during rat liver regenera- tion. As a follow up of our previous study, rat liver tissue was collected after rat 2/3 partial hepatectomy (PH) during the re-organization phase (from days 14 to days 28). Liver DNA was extracted and modified by sodium bisulfate. The methylation status of 10 CpG sites in Egf promoter region was determined using bisulfite sequencing polymerase chain reaction (PCR), as BSP method. The results showed that 3 (sites 3, 4 and 9) out of 10 CpG sites have strikingly methylation changes during the re-organization phase compared to the regeneration phase (from 2 hours to 168 hours, P=0.002, 0.048 and 0.018, respectively). Our results showed that methylation modification of CpGs in the Egf promoter region could be restored to the status before PH operation and changes of methylation didn’t affect Egf mRNA expression during the re-organization phase. PMID:26464832

  7. Regeneration

    Science.gov (United States)

    George A. Schier; Wayne D. Shepperd; John R. Jones

    1985-01-01

    There are basically two approaches to regenerating aspen stands-sexual reproduction using seed, or vegetative regeneration by root suckering. In the West, root suckering is the most practical method. The advantage of having an existing, well established root system capable of producing numerous root suckers easily outweighs natural or artificial reforestation in the...

  8. The circadian optimal time for hepatectomy in the study of liver regeneration.

    Science.gov (United States)

    Souto, M; Llanos, J M

    1985-01-01

    Standardized (light from 0600 to 1800) C3HS mice, hepatectomized at different circadian stages, were killed at 1400 (the peak time of mitotic activity in intact mice). The higher values of mitotic index were those of mice operated at 1400, 48 hr before. The curve of mitotic activity of the regenerating liver of mice operated at 1400 and that of mice operated at 0200 (an opposite time in the circadian stage) are, both, grossly in phase with the curves of mitotic index in young and adult mice liver. The amplitude of the first peak of mitotic activity in mice operated at 0200 was dramatically lower than that of animals operated at 1400. The same applies to hepatocytes as well as to the sinusoid litoral population of cells. It is concluded that 1400 hr, as contrast to 0200 hr, is an optimal time for hepatectomy if one wants to obtain the highest mitotic index first peak during regeneration in a normal phase position (the position of the mitotic index peak in the liver of normal young and adult mice).

  9. Nuclear medicine study of regeneration process of the liver after partial hepatectomy in normal rats

    International Nuclear Information System (INIS)

    Nomura, Yasushi

    1990-01-01

    To evaluate regeneration of the liver in rats after partial hepatectomy based on Higgins' and Anderson's method, the present study reports using the morphological and radionuclide technique. The adult Wistar rats over 8 weeks of age were prepared in this study and were injected intravenously with either 99m Tc-N-(2,6 dimethylphenylcarbamoylmethyl) iminodiacetic acid ( 99m Tc-HIDA) or 99m Tc-phytate. Using Fishback equation, the ratio of wet weight liver regeneration was approximately 80% at 14 days after partial hepatectomy. On pathology, the microscopical findings were as follows: congestion and hepatocytes swelling on day 1; diffuse fat deposition and nuclear division on day 2; decreased hepatocytes swelling, fat deposition, and regular alignment of the hepatocytes on day 5; appearance of normal liver on day 7-14. The uptake and excretion ratio of the hepatocytes using 99m Tc-HIDA as a radionuclide technique recovered to the value prior to partial hepatectomy on day 3, and also the hepatic accumulation coefficient of Kupffer cells using 99m Tc-phytate recoverd on day 4. In conclusion, it was found that the functional recovery employed 3-4 days after partial hepatectomy. The present study using two radiopharmaceuticals describes that the radionuclide techniques can facilitate to evaluate the manifest pathological alterations of hepatocytes and Kupffer cells after partial hepatectomy. (author)

  10. Elevated mitochondrial gene expression during rat liver regeneration after portal vein ligation.

    Science.gov (United States)

    Shimizu, Y; Suzuki, H; Nimura, Y; Onoue, S; Nagino, M; Tanaka, M; Ozawa, T

    1995-10-01

    We explored the molecular basis of mitochondrial energy production during rat liver regeneration after portal vein ligation. Ligation of the left branch of the portal vein induces an increase in the weight of the nonligated lobe, counterbalancing the reduced weight of the ligated lobe. Using this model, we investigated changes in mitochondrial DNA-binding proteins, mitochondrial DNA, and mitochondrial messenger RNA (mRNA) in rat hepatocytes of the nonligated lobes. The amount of mitochondrial DNA-binding protein increased maximally (200% to 300% of the preoperative level) at 12 hours after the operation, before an increase (390%) in mitochondrial DNA content at 24 hours, and parallel to an increase (240%) in mitochondrial mRNA levels at 12 hours. These results suggest that the energy supply for liver regeneration is achieved through enhancement of mitochondrial DNA replication as well as transcription, in which the mitochondrial DNA-binding proteins probably play regulatory roles. We also found that in the nonligated lobes, mRNA levels of hepatocyte growth factor increased to a detectable level only 12 hours after the operation. These molecular biochemical data help explain why preoperative portal vein embolization, which is a modification of portal vein branch ligation, is an effective method to prevent posthepatectomy liver failure.

  11. Progenitor cells in liver regeneration: molecular responses controlling their activation and expansion

    DEFF Research Database (Denmark)

    Santoni-Rugiu, Eric; Jelnes, Peter; Thorgeirsson, Snorri S

    2005-01-01

    created in the liver by a certain insult. This review will focus on molecular responses controlling activation and expansion of the hepatic progenitor cell niche, emphasizing similarities and differences in the microenvironments orchestrating regeneration by recruitment of progenitor cell populations...... cells, and recruited inflammatory cells as well as the variety of growth-modulating molecules produced and/or harboured by these elements. The cellular and molecular responses to different regenerative stimuli seem to depend on the injury inflicted and consequently on the molecular microenvironment...

  12. Regeneration and Agrobacterium-mediated transformation of multiple lily cultivars

    NARCIS (Netherlands)

    Wang, Yue; Kronenburg-van de Ven, van B.C.E.; Menzel, T.R.; Maliepaard, C.A.; Shen, X.; Krens, F.A.

    2012-01-01

    To pursue genetic improvement of lily, efficiency of both regeneration and transformation from callus cultures induced from different explants were evaluated in multiple cultivars. Thirty-five callus lines induced from filaments or styles and one control callus line derived from bulb scales of in

  13. Proteome analysis of a hepatocyte-specific BIRC5 (survivin)-knockout mouse model during liver regeneration.

    Science.gov (United States)

    Bracht, Thilo; Hagemann, Sascha; Loscha, Marius; Megger, Dominik A; Padden, Juliet; Eisenacher, Martin; Kuhlmann, Katja; Meyer, Helmut E; Baba, Hideo A; Sitek, Barbara

    2014-06-06

    The Baculoviral IAP repeat-containing protein 5 (BIRC5), also known as inhibitor of apoptosis protein survivin, is a member of the chromosomal passenger complex and a key player in mitosis. To investigate the function of BIRC5 in liver regeneration, we analyzed a hepatocyte-specific BIRC5-knockout mouse model using a quantitative label-free proteomics approach. Here, we present the analyses of the proteome changes in hepatocyte-specific BIRC5-knockout mice compared to wildtype mice, as well as proteome changes during liver regeneration induced by partial hepatectomy in wildtype mice and mice lacking hepatic BIRC5, respectively. The BIRC5-knockout mice showed an extensive overexpression of proteins related to cellular maintenance, organization and protein synthesis. Key regulators of cell growth, transcription and translation MTOR and STAT1/STAT2 were found to be overexpressed. During liver regeneration proteome changes representing a response to the mitotic stimulus were detected in wildtype mice. Mainly proteins corresponding to proliferation, cell cycle and cytokinesis were up-regulated. The hepatocyte-specific BIRC5-knockout mice showed impaired liver regeneration, which had severe consequences on the proteome level. However, several proteins with function in mitosis were found to be up-regulated upon the proliferative stimulus. Our results show that the E3 ubiquitin-protein ligase UHRF1 is strongly up-regulated during liver regeneration independently of BIRC5.

  14. TRANEXAMIC ACID ACTION ON LIVER REGENERATION AFTER PARTIAL HEPATECTOMY: EXPERIMENTAL MODEL IN RATS.

    Science.gov (United States)

    Sobral, Felipe Antonio; Daga, Henrique; Rasera, Henrique Nogueira; Pinheiro, Matheus da Rocha; Cella, Igor Furlan; Morais, Igor Henrique; Marques, Luciana de Oliveira; Collaço, Luiz Martins

    2016-01-01

    Different lesions may affect the liver resulting in harmful stimuli. Some therapeutic procedures to treat those injuries depend on liver regeneration to increase functional capacity of this organ. Evaluate the effects of tranexamic acid on liver regeneration after partial hepatectomy in rats. 40 rats (Rattus norvegicus albinus, Rodentia mammalia) of Wistar-UP lineage were randomly divided into two groups named control (CT) and tranexamic acid (ATX), with 20 rats in each. Both groups were subdivided, according to liver regeneration time of 32 h or seven days after the rats had been operated. The organ regeneration was evaluated through weight and histology, stained with HE and PCNA. The average animal weight of ATX and CT 7 days groups before surgery were 411.2 g and 432.7 g, and 371.3 g and 392.9 g after the regeneration time, respectively. The average number of mitotic cells stained with HE for the ATX and CT 7 days groups were 33.7 and 32.6 mitosis, and 14.5 and 14.9 for the ATX and CT 32 h groups, respectively. When stained with proliferating cell nuclear antigen, the numbers of mitotic cells counted were 849.7 for the ATX 7 days, 301.8 for the CT 7 days groups, 814.2 for the ATX 32 hand 848.1 for the CT 32 h groups. Tranexamic acid was effective in liver regeneration, but in longer period after partial hepatectomy. Muitas são as injúrias que acometem o fígado e levam a estímulo lesivo. Alguns procedimentos terapêuticos para tratamento dessas lesões dependem da regeneração hepática para aumentar a sua capacidade funcional. Avaliar o efeito do ácido tranexâmico na regeneração hepática após hepatectomia parcial em ratos. Foram utilizados 40 ratos (Rattus norvegicus albinus, Rodentia mammalia) convencionais da linhagem Wistar-UP. Foram divididos aleatoriamente em dois grupos de 20: grupo controle (CT) e grupo ácido tranexâmico (ATX). Cada um deles foi divido em dois subgrupos para avaliar a regeneração hepática no tempo de 32 h e 7 dias do p

  15. Effect of obeticholic acid on liver regeneration following portal vein embolization in an experimental model

    NARCIS (Netherlands)

    Olthof, P. B.; Huisman, F.; Schaap, F. G.; van Lienden, K. P.; Bennink, R. J.; van Golen, R. F.; Heger, M.; Verheij, J.; Jansen, P. L.; Olde Damink, S. W.; van Gulik, T. M.

    2017-01-01

    The bile salt-activated transcription factor farnesoid X receptor (FXR) is a key mediator of proliferative bile salt signalling, which is assumed to play a role in the early phase of compensatory liver growth. The aim of this study was to evaluate the effect of a potent FXR agonist (obeticholic

  16. Deletion of the serotonin transporter in rats disturbs serotonin homeostasis without impairing liver regeneration.

    NARCIS (Netherlands)

    Matondo, R.B.; Punt, C.J.A.; Homberg, J.R.; Toussaint, M.J.; Kisjes, R.; Korporaal, S.J.; Akkerman, J.W.; Cuppen, E.; Bruin, A. de

    2009-01-01

    The serotonin transporter is implicated in the uptake of the vasoconstrictor serotonin from the circulation into the platelets, where 95% of all blood serotonin is stored and released in response to vascular injury. In vivo studies indicated that platelet-derived serotonin mediates liver

  17. Deletion of the serotonin transporter in rats disturbs serotonin homeostasis without impairing liver regeneration

    NARCIS (Netherlands)

    Matondo, R.B.; Punt, C.; Homberg, J.R.; Toussaint, M.J.; Kisjes, R.; Korporaal, S.J.; Akkerman, J.W.; Cuppen, E.; de Bruin, A.

    2009-01-01

    The serotonin transporter is implicated in the uptake of the vasoconstrictor serotonin from the circulation into the platelets, where 95% of all blood serotonin is stored and released in response to vascular injury. In vivo studies indicated that platelet-derived serotonin mediates liver

  18. Reference intervals for putative biomarkers of drug-induced liver injury and liver regeneration in healthy human volunteers.

    Science.gov (United States)

    Francis, Ben; Clarke, Joanna I; Walker, Lauren E; Brillant, Nathalie; Jorgensen, Andrea L; Park, B Kevin; Pirmohamed, Munir; Antoine, Daniel J

    2018-05-02

    The potential of mechanistic biomarkers to improve the prediction of drug-induced liver injury (DILI) and hepatic regeneration is widely acknowledged. We sought to determine reference intervals for new biomarkers of DILI and regeneration as well as to characterize their natural variability and impact of diurnal variation. Serum samples from 200 healthy volunteers were recruited as part of a cross sectional study; of these, 50 subjects had weekly serial sampling over 3 weeks, while 24 had intensive blood sampling over a 24h period. Alanine aminotransferase (ALT), MicroRNA-122 (miR-122), high mobility group box-1 (HMGB1), total keratin-18 (FL-K18), caspase cleaved keratin-18 (cc-K18), glutamate dehydrogenase (GLDH) and colony stimulating factor-1 (CSF-1) were assessed by validated assays. Reference intervals were established for each biomarker based on the 97.5% quantile (90% CI) following the assessment of fixed effects in univariate and multivariable models (ALT 50 (41-50) U/l, miR-122 3548 (2912-4321) copies/µl, HMGB1 2.3 (2.2-2.4) ng/ml, FL-K18 475 (456-488) U/l, cc-K18 272 (256-291) U/l, GLDH 27 (26-30) U/l and CSF-1 2.4 (2.3-2.9) ng/ml). There was a small but significant intra-individual time random effect detected but no significant impact of diurnal variation was observed, with the exception of GLDH. Reference intervals for novel DILI biomarkers have been described for the first time. An upper limit of a reference range might represent the most appropriate method to utilize these data. Regulatory authorities have published letters of support encouraging further qualification of leading candidate biomarkers. These data can now be used to interpret data from exploratory clinical DILI studies and to assist their further qualification. Drug-induced liver injury (DILI) has a big impact on patient health and the development of new medicines. Unfortunately, currently used blood-based tests to assess liver injury and recovery suffer from insufficiencies. Newer blood

  19. Influence of matrix nature on the functional efficacy of biomedical cell product for the regeneration of damaged liver (experimental model of acute liver failure

    Directory of Open Access Journals (Sweden)

    S. V. Gautier

    2017-01-01

    Full Text Available Aim. A comparative analysis of the functional efficacy of biomedical cell products (BMCP for the regeneration of damaged liver based on biopolymer scaffolded porous and hydrogel matrices was performed on the experimental model of acute liver failure. Materials and methods. Matrices allowed for clinical use were employed for BMCP in the form of a sponge made from biopolymer nanostructured composite material (BNCM based on a highly purified bacterial copolymers of poly (β-hydroxybutyrate-co-β-oxyvalerate and polyethylene glycol and a hydrogel matrix from biopolymer microheterogeneous collagen-containing hydrogel (BMCH. Cellular component of BMCP was represented by liver cells and multipotent mesenchymal bone marrow stem cells. The functional efficacy of BMCP for the regeneration of damaged liver was evaluated on the experimental model of acute liver failure in Wistar rats (n = 40 via biochemical, morphological, and immunohistochemical methods. Results. When BMCP was implanted to regenerate the damaged liver on the basis of the scaffolded BNCM or hydrogel BMCH matrices, the lethality in rats with acute liver failure was absent; while in control it was 66.6%. Restoration of the activity of cytolytic enzyme levels and protein-synthetic liver function began on day 9 after modeling acute liver failure, in contrast to the control group, where recovery occurred only by days 18–21. Both matrices maintained the viability and functional activity of liver cells up to 90 days with the formation of blood vessels in BMCP. The obtained data confirm that scaffolded BNCM matrix and hydrogel BMCH matrix retain for a long time (up to 90 days the vital activity of the adherent cells in the BMCP composition, which allows using them to correct acute liver failure. At the same time, hydrogel matrix due to the presence of bioactive components contributes to the creation of the best conditions for adhesion and cell activity which accelerate the regeneration processes

  20. Dopamine-Mediated Sclerotization of Regenerated Chitin in Ionic Liquid

    OpenAIRE

    Oh, Dongyeop X.; Shin, Sara; Lim, Chanoong; Hwang, Dong Soo

    2013-01-01

    Chitin is a promising structural material for biomedical applications, due to its many advantageous properties and abundance in nature. However, its usage and development in the biomedical field have been stagnant, because of chitin’s poor mechanical properties in wet conditions and the difficulties in transforming it into an applicable form. To overcome these challenges, we created a novel biomimetic chitin composite. This regenerated chitin, prepared with ionic liquid, showed improved mecha...

  1. Splenectomy after partial hepatectomy accelerates liver regeneration in mice by promoting tight junction formation via polarity protein Par 3-aPKC.

    Science.gov (United States)

    Liu, Guoxing; Xie, Chengzhi; Fang, Yu; Qian, Ke; Liu, Qiang; Liu, Gao; Cao, Zhenyu; Du, Huihui; Fu, Jie; Xu, Xundi

    2018-01-01

    Several experimental studies have demonstrated that removal of the spleen accelerates liver regeneration after partial hepatectomy. While the mechanism of splenectomy promotes liver regeneration by the improvement of the formation of tight junction and the establishment of hepatocyte polarity is still unknown. We analyzed the cytokines, genes and proteins expression between 70% partial hepatectomy mice (PHx) and simultaneous 70% partial hepatectomy and splenectomy mice (PHs) at predetermined timed points. Compared with the PHx group mice, splenectomy accelerated hepatocyte proliferation in PHs group. The expression of Zonula occludens-1 (ZO-1) indicated that splenectomy promotes the formation of tight junction during liver regeneration. TNF-α, IL-6, HGF, TSP-1 and TGF-β1 were essential factors for the formation of tight junction and the establishment of hepatocytes polarity in liver regeneration. After splenectomy, Partitioning defective 3 homolog (Par 3) and atypical protein kinase C (aPKC) regulate hepatocyte localization and junctional structures in regeneration liver. Our data suggest that the time course expression of TNF-α, IL-6, HGF, TSP-1, and TGF-β1 and the change of platelets take part in liver regeneration. Combination with splenectomy accelerates liver regeneration by improvement of the tight junction formation which may help to establish hepatocyte polarity via Par 3-aPKC. This may provide a clue for us that splenectomy could accelerate liver regeneration after partial hepatectomy of hepatocellular carcinoma and living donor liver transplantation. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Dopamine-Mediated Sclerotization of Regenerated Chitin in Ionic Liquid.

    Science.gov (United States)

    Oh, Dongyeop X; Shin, Sara; Lim, Chanoong; Hwang, Dong Soo

    2013-09-06

    Chitin is a promising structural material for biomedical applications, due to its many advantageous properties and abundance in nature. However, its usage and development in the biomedical field have been stagnant, because of chitin's poor mechanical properties in wet conditions and the difficulties in transforming it into an applicable form. To overcome these challenges, we created a novel biomimetic chitin composite. This regenerated chitin, prepared with ionic liquid, showed improved mechanical properties in wet conditions by mimicking insect cuticle and squid beak sclerotization, i.e. , catechol-meditated cross-linking. By ionic liquid-based heat treatment, dopamine oxidation produced melanin-like compounds and dopamine-meditated cross-links without any solvent evaporation and oxidant utilization. The dopamine-meditated sclerotization increased the ultimate tensile strength (UTS) of the regenerated chitin by 2.52-fold, measured after six weeks of phosphate-buffered saline (PBS) submersion. In addition, the linear swelling ratio (LSR) of the chitin film was reduced by about 22%. This strategy raises a possibility of using regenerated chitin as an artificial hard tissue in wet conditions.

  3. Dopamine-Mediated Sclerotization of Regenerated Chitin in Ionic Liquid

    Directory of Open Access Journals (Sweden)

    Dongyeop X. Oh

    2013-09-01

    Full Text Available Chitin is a promising structural material for biomedical applications, due to its many advantageous properties and abundance in nature. However, its usage and development in the biomedical field have been stagnant, because of chitin’s poor mechanical properties in wet conditions and the difficulties in transforming it into an applicable form. To overcome these challenges, we created a novel biomimetic chitin composite. This regenerated chitin, prepared with ionic liquid, showed improved mechanical properties in wet conditions by mimicking insect cuticle and squid beak sclerotization, i.e., catechol-meditated cross-linking. By ionic liquid-based heat treatment, dopamine oxidation produced melanin-like compounds and dopamine-meditated cross-links without any solvent evaporation and oxidant utilization. The dopamine-meditated sclerotization increased the ultimate tensile strength (UTS of the regenerated chitin by 2.52-fold, measured after six weeks of phosphate-buffered saline (PBS submersion. In addition, the linear swelling ratio (LSR of the chitin film was reduced by about 22%. This strategy raises a possibility of using regenerated chitin as an artificial hard tissue in wet conditions.

  4. Attenuated lipotoxicity and apoptosis is linked to exogenous and endogenous augmenter of liver regeneration by different pathways.

    Science.gov (United States)

    Weiss, Thomas S; Lupke, Madeleine; Ibrahim, Sara; Buechler, Christa; Lorenz, Julia; Ruemmele, Petra; Hofmann, Ute; Melter, Michael; Dayoub, Rania

    2017-01-01

    Nonalcoholic fatty liver disease (NAFLD) covers a spectrum from simple steatosis to nonalcoholic steatohepatitis (NASH) and cirrhosis. Free fatty acids (FFA) induce steatosis and lipo-toxicity and correlate with severity of NAFLD. In this study we aimed to investigate the role of exogenous and endogenous ALR (augmenter of liver regeneration) for FFA induced ER (endoplasmatic reticulum) -stress and lipoapoptosis. Primary human hepatocytes or hepatoma cells either treated with recombinant human ALR (rhALR, 15kDa) or expressing short form ALR (sfALR, 15kDa) were incubated with palmitic acid (PA) and analyzed for lipo-toxicity, -apoptosis, activation of ER-stress response pathways, triacylglycerides (TAG), mRNA and protein expression of lipid metabolizing genes. Both, exogenous rhALR and cytosolic sfALR reduced PA induced caspase 3 activity and Bax protein expression and therefore lipotoxicity. Endogenous sfALR but not rhALR treatment lowered TAG levels, diminished activation of ER-stress mediators C-Jun N-terminal kinase (JNK), X-box binding protein-1 (XBP1) and proapoptotic transcription factor C/EBP-homologous protein (CHOP), and reduced death receptor 5 protein expression. Cellular ALR exerts its lipid lowering and anti-apoptotic actions by enhancing FABP1, which binds toxic FFA, increasing mitochondrial β-oxidation by elevating the mitochondrial FFA transporter CPT1α, and decreasing ELOVL6, which delivers toxic FFA metabolites. We found reduced hepatic mRNA levels of ALR in a high fat diet mouse model, and of ALR and FOXA2, a transcription factor inducing ALR expression, in human steatotic as well as NASH liver samples, which may explain increased lipid deposition and reduced β-oxidation in NASH patients. Present study shows that exogenous and endogenous ALR reduce PA induced lipoapoptosis. Furthermore, cytosolic sfALR changes mRNA and protein expression of genes regulating lipid metabolism, reduces ER-stress finally impeding progression of NASH.

  5. Attenuated lipotoxicity and apoptosis is linked to exogenous and endogenous augmenter of liver regeneration by different pathways.

    Directory of Open Access Journals (Sweden)

    Thomas S Weiss

    Full Text Available Nonalcoholic fatty liver disease (NAFLD covers a spectrum from simple steatosis to nonalcoholic steatohepatitis (NASH and cirrhosis. Free fatty acids (FFA induce steatosis and lipo-toxicity and correlate with severity of NAFLD. In this study we aimed to investigate the role of exogenous and endogenous ALR (augmenter of liver regeneration for FFA induced ER (endoplasmatic reticulum -stress and lipoapoptosis. Primary human hepatocytes or hepatoma cells either treated with recombinant human ALR (rhALR, 15kDa or expressing short form ALR (sfALR, 15kDa were incubated with palmitic acid (PA and analyzed for lipo-toxicity, -apoptosis, activation of ER-stress response pathways, triacylglycerides (TAG, mRNA and protein expression of lipid metabolizing genes. Both, exogenous rhALR and cytosolic sfALR reduced PA induced caspase 3 activity and Bax protein expression and therefore lipotoxicity. Endogenous sfALR but not rhALR treatment lowered TAG levels, diminished activation of ER-stress mediators C-Jun N-terminal kinase (JNK, X-box binding protein-1 (XBP1 and proapoptotic transcription factor C/EBP-homologous protein (CHOP, and reduced death receptor 5 protein expression. Cellular ALR exerts its lipid lowering and anti-apoptotic actions by enhancing FABP1, which binds toxic FFA, increasing mitochondrial β-oxidation by elevating the mitochondrial FFA transporter CPT1α, and decreasing ELOVL6, which delivers toxic FFA metabolites. We found reduced hepatic mRNA levels of ALR in a high fat diet mouse model, and of ALR and FOXA2, a transcription factor inducing ALR expression, in human steatotic as well as NASH liver samples, which may explain increased lipid deposition and reduced β-oxidation in NASH patients. Present study shows that exogenous and endogenous ALR reduce PA induced lipoapoptosis. Furthermore, cytosolic sfALR changes mRNA and protein expression of genes regulating lipid metabolism, reduces ER-stress finally impeding progression of NASH.

  6. A20 modulates lipid metabolism and energy production to promote liver regeneration.

    Directory of Open Access Journals (Sweden)

    Scott M Damrauer

    2011-03-01

    Full Text Available Liver regeneration is clinically of major importance in the setting of liver injury, resection or transplantation. We have demonstrated that the NF-κB inhibitory protein A20 significantly improves recovery of liver function and mass following extended liver resection (LR in mice. In this study, we explored the Systems Biology modulated by A20 following extended LR in mice.We performed transcriptional profiling using Affymetrix-Mouse 430.2 arrays on liver mRNA retrieved from recombinant adenovirus A20 (rAd.A20 and rAd.βgalactosidase treated livers, before and 24 hours after 78% LR. A20 overexpression impacted 1595 genes that were enriched for biological processes related to inflammatory and immune responses, cellular proliferation, energy production, oxidoreductase activity, and lipid and fatty acid metabolism. These pathways were modulated by A20 in a manner that favored decreased inflammation, heightened proliferation, and optimized metabolic control and energy production. Promoter analysis identified several transcriptional factors that implemented the effects of A20, including NF-κB, CEBPA, OCT-1, OCT-4 and EGR1. Interactive scale-free network analysis captured the key genes that delivered the specific functions of A20. Most of these genes were affected at basal level and after resection. We validated a number of A20's target genes by real-time PCR, including p21, the mitochondrial solute carriers SLC25a10 and SLC25a13, and the fatty acid metabolism regulator, peroxisome proliferator activated receptor alpha. This resulted in greater energy production in A20-expressing livers following LR, as demonstrated by increased enzymatic activity of cytochrome c oxidase, or mitochondrial complex IV.This Systems Biology-based analysis unravels novel mechanisms supporting the pro-regenerative function of A20 in the liver, by optimizing energy production through improved lipid/fatty acid metabolism, and down-regulated inflammation. These findings

  7. The yield of genome mutations in cells of intact and regenerating rat liver in normal conditions and after γ-irradiation

    International Nuclear Information System (INIS)

    Gil'yano, N.Ya.; Malinovskij, O.V.

    1984-01-01

    A comparative study was made of spontaneus and induced polyploidy in cells of resting and regenerating rat liver. Polyploidy was shown to play a major role in the ontogenesis and during regeneration after partial hepatectomy. An essential difference was revealed in the radiation response of cells of intact and regenerating liver with respect to the yield of polyploid cells. This distinction was referped to different effectiveness of the processes of repair and fixation of radiation damages in the actively proliferating and resting cells

  8. RACK1-mediated translation control promotes liver fibrogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Min; Peng, Peike; Wang, Jiajun [Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai 200032 (China); Wang, Lan; Duan, Fangfang [Institute of Biomedical Science, Fudan University, Shanghai 200032 (China); Jia, Dongwei, E-mail: jiadongwei@fudan.edu.cn [Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai 200032 (China); Ruan, Yuanyuan, E-mail: yuanyuanruan@fudan.edu.cn [Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai 200032 (China); Gu, Jianxin [Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai 200032 (China); Institute of Biomedical Science, Fudan University, Shanghai 200032 (China)

    2015-07-31

    Activation of quiescent hepatic stellate cells (HSCs) is the central event of liver fibrosis. The translational machinery is an optimized molecular network that affects cellular homoeostasis and diseases, whereas the role of protein translation in HSCs activation and liver fibrosis is little defined. Our previous report suggests that up-regulation of receptor for activated C-kinase 1(RACK1) in HSCs is critical for liver fibrogenesis. In this study, we found that RACK1 promoted macrophage conditioned medium (MCM)-induced assembly of eIF4F and phosphorylation of eIF4E in primary HSCs. RACK1 enhanced the translation and expression of pro-fibrogenic factors collagen 1α1, snail and cyclin E1 induced by MCM. Administration of PP242 or knock-down of eIF4E suppressed RACK1-stimulated collagen 1α1 production, proliferation and migration in primary HSCs. In addition, depletion of eIF4E attenuated thioacetamide (TAA)-induced liver fibrosis in vivo. Our data suggest that RACK1-mediated stimulation of cap-dependent translation plays crucial roles in HSCs activation and liver fibrogenesis, and targeting translation initiation could be a promising strategy for the treatment of liver fibrosis. - Highlights: • RACK1 induces the assembly of eIF4F and phosphorylation of eIF4E in primary HSCs. • RACK1 stimulates the translation of collagen 1α1, snail and cyclin E1 in HSCs. • RACK1 promotes HSCs activation via cap-mediated translation. • Depletion of eIF4E suppresses liver fibrogenesis in vivo.

  9. RACK1-mediated translation control promotes liver fibrogenesis

    International Nuclear Information System (INIS)

    Liu, Min; Peng, Peike; Wang, Jiajun; Wang, Lan; Duan, Fangfang; Jia, Dongwei; Ruan, Yuanyuan; Gu, Jianxin

    2015-01-01

    Activation of quiescent hepatic stellate cells (HSCs) is the central event of liver fibrosis. The translational machinery is an optimized molecular network that affects cellular homoeostasis and diseases, whereas the role of protein translation in HSCs activation and liver fibrosis is little defined. Our previous report suggests that up-regulation of receptor for activated C-kinase 1(RACK1) in HSCs is critical for liver fibrogenesis. In this study, we found that RACK1 promoted macrophage conditioned medium (MCM)-induced assembly of eIF4F and phosphorylation of eIF4E in primary HSCs. RACK1 enhanced the translation and expression of pro-fibrogenic factors collagen 1α1, snail and cyclin E1 induced by MCM. Administration of PP242 or knock-down of eIF4E suppressed RACK1-stimulated collagen 1α1 production, proliferation and migration in primary HSCs. In addition, depletion of eIF4E attenuated thioacetamide (TAA)-induced liver fibrosis in vivo. Our data suggest that RACK1-mediated stimulation of cap-dependent translation plays crucial roles in HSCs activation and liver fibrogenesis, and targeting translation initiation could be a promising strategy for the treatment of liver fibrosis. - Highlights: • RACK1 induces the assembly of eIF4F and phosphorylation of eIF4E in primary HSCs. • RACK1 stimulates the translation of collagen 1α1, snail and cyclin E1 in HSCs. • RACK1 promotes HSCs activation via cap-mediated translation. • Depletion of eIF4E suppresses liver fibrogenesis in vivo

  10. Mechanisms of bile acid mediated inflammation in the liver.

    Science.gov (United States)

    Li, Man; Cai, Shi-Ying; Boyer, James L

    2017-08-01

    Bile acids are synthesized in the liver and are the major component in bile. Impaired bile flow leads to cholestasis that is characterized by elevated levels of bile acid in the liver and serum, followed by hepatocyte and biliary injury. Although the causes of cholestasis have been extensively studied, the molecular mechanisms as to how bile acids initiate liver injury remain controversial. In this chapter, we summarize recent advances in the pathogenesis of bile acid induced liver injury. These include bile acid signaling pathways in hepatocytes as well as the response of cholangiocytes and innate immune cells in the liver in both patients with cholestasis and cholestatic animal models. We focus on how bile acids trigger the production of molecular mediators of neutrophil recruitment and the role of the inflammatory response in this pathological process. These advances point to a number of novel targets where drugs might be judged to be effective therapies for cholestatic liver injury. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Liver remnant regeneration in donors after living donor liver transplantation. Long-term follow-up using CT and MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Klink, T. [INSELSPITAL - Bern University Hospital (Switzerland). Diagnostic, Interventional, and Pediatric Radiology; University Medical Center Hamburg-Eppendorf, Hamburg (Germany). Diagnostic and Interventional Radiology; Simon, P. [Merciful Brethren Hospital, Trier (Germany). Dept. of Radiology, Neuroradiology, Sonography and Nuclearmedicine; University Medical Center Hamburg-Eppendorf, Hamburg (Germany). Diagnostic and Interventional Radiology; Knopp, C.; Ittrich, H.; Adam, G.; Koops, A. [University Medical Center Hamburg-Eppendorf, Hamburg (Germany). Diagnostic and Interventional Radiology; Fischer, L. [University Medical Center Hamburg-Eppendorf, Hamburg (Germany). Dept. of Hepatobiliary Surgery and Transplant Surgery

    2014-06-15

    Purpose: To assess liver remnant volume regeneration and maintenance, and complications in the long-time follow-up of donors after living donor liver transplantation using CT and MRI. Materials and Methods: 47 donors with a mean age of 33.5 years who donated liver tissue for transplantation and who were available for follow-up imaging were included in this retrospective study. Contrast-enhanced CT and MR studies were acquired for routine follow-up. Two observers evaluated pre- and postoperative images regarding anatomy and pathological findings. Volumes were manually measured on contrast-enhanced images in the portal venous phase, and potential postoperative complications were documented. Pre- and postoperative liver volumes were compared for evaluating liver remnant regeneration. Results: 47 preoperative and 89 follow-up studies covered a period of 22.4 months (range: 1 - 84). After right liver lobe (RLL) donation, the mean liver remnant volume was 522.0 ml (± 144.0; 36.1%; n = 18), after left lateral section (LLS) donation 1,121.7 ml (± 212.8; 79.9%; n = 24), and after left liver lobe (LLL) donation 1,181.5 ml (± 279.5; 72.0%; n = 5). Twelve months after donation, the liver remnant volume were 87.3% (RLL; ± 11.8; n = 11), 95.0% (LS; ± 11.6; n = 18), and 80.1% (LLL; ± 2.0; n = 2 LLL) of the preoperative total liver volume. Rapid initial regeneration and maintenance at 80% of the preoperative liver volume were observed over the total follow-up period. Minor postoperative complications were found early in 4 patients. No severe or late complications or mortality occurred. Conclusion: Rapid regeneration of liver remnant volumes in all donors and volume maintenance over the long-term follow-up period of up to 84 months without severe or late complications are important observations for assessing the safety of LDLT donors. (orig.)

  12. Liver remnant regeneration in donors after living donor liver transplantation. Long-term follow-up using CT and MR imaging

    International Nuclear Information System (INIS)

    Klink, T.; University Medical Center Hamburg-Eppendorf, Hamburg; Simon, P.; University Medical Center Hamburg-Eppendorf, Hamburg; Knopp, C.; Ittrich, H.; Adam, G.; Koops, A.; Fischer, L.

    2014-01-01

    Purpose: To assess liver remnant volume regeneration and maintenance, and complications in the long-time follow-up of donors after living donor liver transplantation using CT and MRI. Materials and Methods: 47 donors with a mean age of 33.5 years who donated liver tissue for transplantation and who were available for follow-up imaging were included in this retrospective study. Contrast-enhanced CT and MR studies were acquired for routine follow-up. Two observers evaluated pre- and postoperative images regarding anatomy and pathological findings. Volumes were manually measured on contrast-enhanced images in the portal venous phase, and potential postoperative complications were documented. Pre- and postoperative liver volumes were compared for evaluating liver remnant regeneration. Results: 47 preoperative and 89 follow-up studies covered a period of 22.4 months (range: 1 - 84). After right liver lobe (RLL) donation, the mean liver remnant volume was 522.0 ml (± 144.0; 36.1%; n = 18), after left lateral section (LLS) donation 1,121.7 ml (± 212.8; 79.9%; n = 24), and after left liver lobe (LLL) donation 1,181.5 ml (± 279.5; 72.0%; n = 5). Twelve months after donation, the liver remnant volume were 87.3% (RLL; ± 11.8; n = 11), 95.0% (LS; ± 11.6; n = 18), and 80.1% (LLL; ± 2.0; n = 2 LLL) of the preoperative total liver volume. Rapid initial regeneration and maintenance at 80% of the preoperative liver volume were observed over the total follow-up period. Minor postoperative complications were found early in 4 patients. No severe or late complications or mortality occurred. Conclusion: Rapid regeneration of liver remnant volumes in all donors and volume maintenance over the long-term follow-up period of up to 84 months without severe or late complications are important observations for assessing the safety of LDLT donors. (orig.)

  13. Robust regeneration protocol for the Agrobacterium tumefaciens mediated transformation of Solanum tuberosum

    International Nuclear Information System (INIS)

    Abbasi, A.; Bilal, M.; Hussain, J.; Shah, M. M.; Hassan, A.

    2016-01-01

    Plant genetic transformation requires robust regeneration system. Plant growth regulators (PGRs) such as cytokinins (CKs) play a pivotal role in organogenesis; however, CKs are the most expensive PGRs. In the current study, an efficient yet economical protocol for regeneration of potato plant was developed. Stem inter-nodal and leaf explants were cultured on different regeneration media supplemented with varying concentration of different CKs such as kinetin and zeatin. Murashige- Skoog media added with zeatin (1, 1.5 mg/L) was designated as RZ1, RZ1.5, respectively or kinetin (1.5, 2 mg/L) was designated as RK1.5 and RK2, respectively, however, concentrations of other hormones such as NAA (1-Naphthaleneacetic acid) and GA3 (Gibberellic acid A3) were kept same. RZ1 and RZ1.5 gave significantly better Results as compared to RK-type media in all aspects studied such as callus initiation, days to first shoot emergence, number of shoots per explants. RZ1 medium was then selected as regeneration media for Agrobacterium-mediated transformation of potato plants with cyanobacterial phosphoenol pyruvate carboxylase gene, which provided multiple putative transformants on selection media. The transformants were further confirmed through PCR. The current protocol is found to be cost effective and efficient for the regeneration of Solanum tuberosum and can be successfully implied for the Agrobacterium-mediated transformation. (author)

  14. DNA alkylation and tumor induction in regenerating rat liver after cell cycle-related continuous N-nitrosodimethylamine infusion

    Energy Technology Data Exchange (ETDEWEB)

    Rabes, H.M.; Kerler, R.; Wilhelm, R.

    1983-01-01

    Synchronized regenerating rat liver after partial hepatectomy was used to study cell cycle-related DNA base alkylation and liver carcinogenesis. A continuous iv infusion of (/sup 14/C)N-nitrosodimethylamine (DMN) at a dose of 0.5 mg/kg/hour was given to inbred male Wistar Af/Han rats over a period of 8 hours either during the G1 phase, hydroxyurea-synchronized DNA synthesis, or the G2+M-phase of regenerating liver or to untreated rats (G0-phase liver--carcinogen dose, 1.5 mg/kg/hour). Two hours after the end of the infusion, the amount of 7-methylguanine was highest in the G0-phase liver, with a decrease in the G1 phase, the S-phase, and the G2+M-phase. After continuous DMN exposure, the O/sub 6/-methylguanine:7-methylguanine ratio was lower in the S-phase and G2+M-phase livers than in the G0-phase and G1-phase livers, indicating an increased O/sub 6/-methylguanine repair during DNA synthesis and the G2+M-phase. Liver tumors in rats treated by continuous DMN infusion either during the G0 phase or the S-phase developed only after carcinogen exposure during DNA synthesis.

  15. DNMT1 is a Required Genomic Regulator for Murine Liver Histogenesis and Regeneration

    DEFF Research Database (Denmark)

    Kaji, Kosuke; Factor, Valentina M; Andersen, Jesper B

    2016-01-01

    as transcriptome and methylation profiling. Regenerative growth was induced by partial hepatectomy and exposure to CCl4 . The impact of Dnmt1 knockdown was also analyzed in hepatic progenitor cell (HPC) lines; proliferation, apoptosis, DNA damage and sphere formation were assessed. Dnmt1 loss in postnatal...... hepatocytes caused global hypomethylation, enhanced DNA damage response and initiated a senescence state causing a progressive inability to maintain tissue homeostasis and proliferate in response to injury. The liver regenerated via activation and repopulation from progenitors due to lineage......-dependent differences in Alb-Cre expression, providing a basis for selection of less mature and therefore less damaged HPC progeny. Consistently, an efficient knockdown of Dnmt1 in cultured HPCs caused severe DNA damage, cell cycle arrest, senescence and cell death. Mx1-Cre-driven deletion of Dnmt1 in adult quiescent...

  16. Fibroblast growth factor 15/19 (FGF15/19) protects from diet-induced hepatic steatosis: development of an FGF19-based chimeric molecule to promote fatty liver regeneration.

    Science.gov (United States)

    Alvarez-Sola, Gloria; Uriarte, Iker; Latasa, M Ujue; Fernandez-Barrena, Maite G; Urtasun, Raquel; Elizalde, Maria; Barcena-Varela, Marina; Jiménez, Maddalen; Chang, Haisul C; Barbero, Roberto; Catalán, Victoria; Rodríguez, Amaia; Frühbeck, Gema; Gallego-Escuredo, José M; Gavaldà-Navarro, Aleix; Villarroya, Francesc; Rodriguez-Ortigosa, Carlos M; Corrales, Fernando J; Prieto, Jesus; Berraondo, Pedro; Berasain, Carmen; Avila, Matias A

    2017-10-01

    Fibroblast growth factor 15/19 (FGF15/19), an enterokine that regulates synthesis of hepatic bile acids (BA), has been proposed to influence fat metabolism. Without FGF15/19, mouse liver regeneration after partial hepatectomy (PH) is severely impaired. We studied the role of FGF15/19 in response to a high fat diet (HFD) and its regulation by saturated fatty acids. We developed a fusion molecule encompassing FGF19 and apolipoprotein A-I, termed Fibapo, and evaluated its pharmacological properties in fatty liver regeneration. Fgf15 -/- mice were fed a HFD. Liver fat and the expression of fat metabolism and endoplasmic reticulum (ER) stress-related genes were measured. Influence of palmitic acid (PA) on FGF15/19 expression was determined in mice and in human liver cell lines. In vivo half-life and biological activity of Fibapo and FGF19 were compared. Hepatoprotective and proregenerative activities of Fibapo were evaluated in obese db/db mice undergoing PH. Hepatosteatosis and ER stress were exacerbated in HFD-fed Fgf15 -/- mice. Hepatic expression of Pparγ2 was elevated in Fgf15 -/- mice, being reversed by FGF19 treatment. PA induced FGF15/19 expression in mouse ileum and human liver cells, and FGF19 protected from PA-mediated ER stress and cytotoxicity. Fibapo reduced liver BA and lipid accumulation, inhibited ER stress and showed enhanced half-life. Fibapo provided increased db/db mice survival and improved regeneration upon PH. FGF15/19 is essential for hepatic metabolic adaptation to dietary fat being a physiological regulator of Pparγ2 expression . Perioperative administration of Fibapo improves fatty liver regeneration. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  17. Oxaliplatin but Not Irinotecan Impairs Posthepatectomy Liver Regeneration in a Murine Model

    Directory of Open Access Journals (Sweden)

    Perry A. Soriano

    2011-01-01

    Full Text Available Introduction. We examined the murine hepatectomy model of liver regeneration (LR in the setting of neoadjuvant chemotherapy. Methods. C57BL/6 mice were randomized to receive neoadjuvant intraperitoneal (IP injections of a control, oxaliplatin (15 mg/kg, or irinotecan (100 mg/Kg or 250 mg/Kg solution. Hepatectomy (70% was performed 14 days after the final IP treatment. Animals were sacrificed at postoperative day (D 0, 1, 2, 3, and 7. Liver remnants and serum were collected for analysis. -tests for independent samples were used for statistical comparisons. Results. For oxaliplatin, percent LR did not differ at D1 or D2 but was significantly less at D3 (89.0% versus 70.0%, =0.048 with no difference on D7 (=0.21. Irinotecan-treated mice at both dose levels (100 mg/Kg and 250 mg/Kg showed no significant differences in LR. BrdU incorporation was significantly decreased in oxaliplatin-treated animals (D1,2,3. Conclusions. Neoadjuvant oxaliplatin but not irinotecan impairs early LR in a posthepatectomy murine model which correlates with decreased DNA synthesis.

  18. Oxaliplatin but Not Irinotecan Impairs Posthepatectomy Liver Regeneration in a Murine Model

    Science.gov (United States)

    Soriano, Perry A.; Liu, Nian; Castillo, Erick; Foster, Brock; Artinyan, Avo; Kim, Joseph; Huang, Wendong; Wagman, Lawrence D.

    2011-01-01

    Introduction. We examined the murine hepatectomy model of liver regeneration (LR) in the setting of neoadjuvant chemotherapy. Methods. C57BL/6 mice were randomized to receive neoadjuvant intraperitoneal (IP) injections of a control, oxaliplatin (15 mg/kg), or irinotecan (100 mg/Kg or 250 mg/Kg) solution. Hepatectomy (70%) was performed 14 days after the final IP treatment. Animals were sacrificed at postoperative day (D) 0, 1, 2, 3, and 7. Liver remnants and serum were collected for analysis. T-tests for independent samples were used for statistical comparisons. Results. For oxaliplatin, percent LR did not differ at D1 or D2 but was significantly less at D3 (89.0% versus 70.0%, P = 0.048) with no difference on D7 (P = 0.21). Irinotecan-treated mice at both dose levels (100 mg/Kg and 250 mg/Kg) showed no significant differences in LR. BrdU incorporation was significantly decreased in oxaliplatin-treated animals (D1,2,3). Conclusions. Neoadjuvant oxaliplatin but not irinotecan impairs early LR in a posthepatectomy murine model which correlates with decreased DNA synthesis. PMID:22164336

  19. The nuclear pore density in rat liver cells upon regeneration and total body X-ray irradiation

    International Nuclear Information System (INIS)

    Kuz'mina, S.N.; Troitskaya, L.P.; Mirkhamidova, P.A.; Bul'dyaeva, T.V.; Zbarskij, I.B.; Grigor'ev, V.B.; Akademiya Meditsinskikh Nauk SSSR, Moscow. Inst. Virusologii)

    1979-01-01

    The nuclear pore density has been investigated in rat liver cells in the course of regeneration and X-ray irradiation. It has been found that the number of pore complexes (PC) per nuclear shell (NS) unit area in the liver cells is not constant. In an hour following whole-body irradiation of rats with a regenerating liver at the 1200 R dose the number of PC per 1 μm 2 of the nuclear shell area decreases by 5, 8 times as compared with the PC density in the regenerating liver cells of the irradiated rats, the PC degradation and structural rupture being observed. It has been established by means of the freezing-etching method which enables PC surfaces observation as for cytoplasma as well as for nucleoplasma that the PC peripheral granulas and the central granula consist of subparticles being approximately of the same size. The central granula forms a channel through which the material containing RNA passes from the nucleus to the cytoplasma. On the basis of the fact that the treatement by Triton X-100, disarranging the integrity of the NS membranous structure, preserves PC in relation to the fibrous layer as well as on the basis of the unequal nuclear pore state observed on the platinum-carbon replicas from nuclei splits it is supposed that PC can be formed in the nucleus and then in the course of repening ''built in'' PS

  20. Immunohistochemical analyses of cell cycle progression and gene expression of biliary epithelial cells during liver regeneration after partial hepatectomy of the mouse.

    Science.gov (United States)

    Fukuda, Tatsuya; Fukuchi, Tomokazu; Yagi, Shinomi; Shiojiri, Nobuyoshi

    2016-05-20

    The liver has a remarkable regeneration capacity, and, after surgical removal of its mass, the remaining tissue undergoes rapid regeneration through compensatory growth of its constituent cells. Although hepatocytes synchronously proliferate under the control of various signaling molecules from neighboring cells, there have been few detailed analyses on how biliary cells regenerate for their cell population after liver resection. The present study was undertaken to clarify how biliary cells regenerate after partial hepatectomy of mice through extensive analyses of their cell cycle progression and gene expression using immunohistochemical and RT-PCR techniques. When expression of PCNA, Ki67 antigen, topoisomerase IIα and phosphorylated histone H3, which are cell cycle markers, was immunohistochemically examined during liver regeneration, hepatocytes had a peak of the S phase and M phase at 48-72 h after resection. By contrast, biliary epithelial cells had much lower proliferative activity than that of hepatocytes, and their peak of the S phase was delayed. Mitotic figures were rarely detectable in biliary cells. RT-PCR analyses of gene expression of biliary markers such as Spp1 (osteopontin), Epcam and Hnf1b demonstrated that they were upregulated during liver regeneration. Periportal hepatocytes expressed some of biliary markers, including Spp1 mRNA and protein. Some periportal hepatocytes had downregulated expression of HNF4α and HNF1α. Gene expression of Notch signaling molecules responsible for cell fate decision of hepatoblasts to biliary cells during development was upregulated during liver regeneration. Notch signaling may be involved in biliary regeneration.

  1. Liver regeneration after partial hepatectomy in rat is more impaired in a steatotic liver induced by dietary fructose compared to dietary fat

    International Nuclear Information System (INIS)

    Tanoue, Shirou; Uto, Hirofumi; Kumamoto, Ryo; Arima, Shiho; Hashimoto, Shinichi; Nasu, Yuichiro; Takami, Yoichiro; Moriuchi, Akihiro; Sakiyama, Toshio; Oketani, Makoto; Ido, Akio; Tsubouchi, Hirohito

    2011-01-01

    Highlights: → Hepatic steatosis in rats fed a high fructose diet was less severe than that in rats fed a high fat diet. → Liver regeneration was more impaired in rats fed a high fructose diet than in rats fed a high fat diet. → Dysregulation of genes associated with metabolism may contribute to impairment of liver regeneration. → Regulation of the TGF-β1 level after partial hepatectomy may be impaired in rats fed a high fructose diet. -- Abstract: Hepatic steatosis (HS) has a negative effect on liver regeneration, but different pathophysiologies of HS may lead to different outcomes. Male Sprague-Dawley rats were fed a high fructose (66% fructose; H-fruc), high fat (54% fat; H-fat), or control chow diet for 4 weeks. Based on hepatic triglyceride content and oil red O staining, HS developed in the H-fruc group, but was less severe compared to the H-fat group. Hepatic mRNA expression levels of fatty acid synthase and fructokinase were increased and those of carnitine palmitoyltransferase-1 and peroxisome proliferator-activated receptor-α were decreased in the H-fruc group compared to the H-fat group. Liver regeneration after 70% partial hepatectomy (PHx) was evaluated by measuring the increase in postoperative liver mass and PCNA-positive hepatocytes, and was impaired in the H-fruc group compared to the H-fat and control groups on days 3 and 7. Serum levels of tumor necrosis factor-α, interleukin-6 and hepatocyte growth factor did not change significantly after PHx. In contrast, serum TGF-β1 levels were slightly but significantly lower in the control group on day 1 and in the H-fat group on day 3 compared to the level in each group on day 0, and then gradually increased. However, the serum TGF-β1 level did not change after PHx in the H-fruc group. These results indicate that impairment of liver regeneration after PHx in HS is related to the cause, rather than the degree, of steatosis. This difference may result from altered metabolic gene expression

  2. Liver regeneration after partial hepatectomy in rat is more impaired in a steatotic liver induced by dietary fructose compared to dietary fat

    Energy Technology Data Exchange (ETDEWEB)

    Tanoue, Shirou [Department of Digestive and Lifestyle-Related Diseases, Kagoshima University, Graduate School of Medical and Dental Sciences, Kagoshima (Japan); Uto, Hirofumi, E-mail: hirouto@m2.kufm.kagoshima-u.ac.jp [Department of Digestive and Lifestyle-Related Diseases, Kagoshima University, Graduate School of Medical and Dental Sciences, Kagoshima (Japan); Kumamoto, Ryo; Arima, Shiho; Hashimoto, Shinichi; Nasu, Yuichiro; Takami, Yoichiro; Moriuchi, Akihiro; Sakiyama, Toshio; Oketani, Makoto; Ido, Akio; Tsubouchi, Hirohito [Department of Digestive and Lifestyle-Related Diseases, Kagoshima University, Graduate School of Medical and Dental Sciences, Kagoshima (Japan)

    2011-04-01

    Highlights: {yields} Hepatic steatosis in rats fed a high fructose diet was less severe than that in rats fed a high fat diet. {yields} Liver regeneration was more impaired in rats fed a high fructose diet than in rats fed a high fat diet. {yields} Dysregulation of genes associated with metabolism may contribute to impairment of liver regeneration. {yields} Regulation of the TGF-{beta}1 level after partial hepatectomy may be impaired in rats fed a high fructose diet. -- Abstract: Hepatic steatosis (HS) has a negative effect on liver regeneration, but different pathophysiologies of HS may lead to different outcomes. Male Sprague-Dawley rats were fed a high fructose (66% fructose; H-fruc), high fat (54% fat; H-fat), or control chow diet for 4 weeks. Based on hepatic triglyceride content and oil red O staining, HS developed in the H-fruc group, but was less severe compared to the H-fat group. Hepatic mRNA expression levels of fatty acid synthase and fructokinase were increased and those of carnitine palmitoyltransferase-1 and peroxisome proliferator-activated receptor-{alpha} were decreased in the H-fruc group compared to the H-fat group. Liver regeneration after 70% partial hepatectomy (PHx) was evaluated by measuring the increase in postoperative liver mass and PCNA-positive hepatocytes, and was impaired in the H-fruc group compared to the H-fat and control groups on days 3 and 7. Serum levels of tumor necrosis factor-{alpha}, interleukin-6 and hepatocyte growth factor did not change significantly after PHx. In contrast, serum TGF-{beta}1 levels were slightly but significantly lower in the control group on day 1 and in the H-fat group on day 3 compared to the level in each group on day 0, and then gradually increased. However, the serum TGF-{beta}1 level did not change after PHx in the H-fruc group. These results indicate that impairment of liver regeneration after PHx in HS is related to the cause, rather than the degree, of steatosis. This difference may result

  3. The liver taxis of receptor mediated lactosaminated human growth hormone

    International Nuclear Information System (INIS)

    Chen Zelian; Shi Lin; Li Tongling; Pang Qijie; He Juying; Guan Changtian

    2002-01-01

    Radiography imaging is used to assess liver taxis mechanism of anti-dwarfism drug lactosaminated human growth hormone (L-rhGH). Both L-rhGH and rhGH labelled with 131 I are used to study their biodistribution in animals (including rabbits, cocks and rats). The results show that L-rhGH is of specific hepatic targeting property, and the maximum hepatic concentration rate is 76.8%, which is two times of rhGH. Its hepatic binding is receptor mediated

  4. Augmenter of liver regeneration causes different kinetics of ERK1/2 and Akt/PKB phosphorylation than EGF and induces hepatocyte proliferation in an EGF receptor independent and liver specific manner

    Energy Technology Data Exchange (ETDEWEB)

    Ilowski, Maren; Putz, Christine [Department of Surgery, Ludwig-Maximilians-University of Munich Hospital Grosshadern, Munich (Germany); Weiss, Thomas S. [Department of Surgery, University of Regensburg Hospital, Regensburg (Germany); Brand, Stephan [Department of Internal Medicine II, Ludwig-Maximilians-University of Munich Hospital Grosshadern, Munich (Germany); Jauch, Karl-Walter [Department of Surgery, Ludwig-Maximilians-University of Munich Hospital Grosshadern, Munich (Germany); Hengstler, Jan G. [Leibniz Research Centre for Working Environment and Human Factors, TU Dortmund University, Dortmund (Germany); Thasler, Wolfgang Erwin, E-mail: wolfgang.thasler@med.uni-muenchen.de [Department of Surgery, Ludwig-Maximilians-University of Munich Hospital Grosshadern, Munich (Germany)

    2010-04-16

    Background/Aim: Augmenter of liver regeneration (ALR) is a potent growth factor which supports liver regeneration in experimental animals. The aim of this study was to compare proliferation as well as the kinetics of ERK1/2 and Akt/PKB phosphorylation by recombinant human ALR (rhALR) and EGF in human hepatocytes and extrahepatic cells. Methods: Kinetics of ERK1/2 and Akt/PKB phosphorylation were determined in primary human hepatocytes (phh) after stimulation with rhALR and EGF. Induction of proliferation was analyzed in phh and several cell lines of hepatic and extrahepatic origin by the MTT and [{sup 3}H]-thymidine assay. Results: The kinetics of ERK phosphorylation showed clear differences, whereby rhALR caused a transient and EGF a permanent increase during the observation period of 60 min. For both, Akt and ERK phosphorylation, EGF caused a faster effect with maximal levels observed already after 2 min, whereas rhALR caused maximal phosphorylation between 10 and 15 min. Using the EGF receptor inhibitor AG1478 we provide evidence of an EGF receptor independent induction of proliferation by rhALR. Furthermore, rhALR induced proliferation only in phh and the human liver derived cell lines HepG2 and Chang. In contrast, EGF enhanced proliferation in all analyzed cell types including cell lines of colon, bronchial, pancreatic and gastric origin (SW480, BC1, L36PL and GC1). Conclusion: rhALR and EGF induce different kinetics of ERK and Akt phosphorylation in human hepatocytes. The mitogenic effect of rhALR is liver specific and seems to be at least partially independent from EGF receptor mediated signaling.

  5. Effect of Picibanil (OK 432) on the Scavenging Effect of Free Radicals Produced during Liver Regeneration in the Rat

    OpenAIRE

    Okamoto, Ko; Hamazaki, Keisuke; Iwagaki, Hiromi; Orita, Kunzo; Mori, Akitane

    1995-01-01

    We administered a biological response modifier Picibanil (OK-432), attenuated Streptococcus pyogenes, via the dorsal vein of the penis after 70% hepatectomy in rats, and clarified the scavenging effect of Picibanil on free radicals generated in the regenerating liver. A group of 5 rats was intravenously administered with 25 KE/kg of OK-432 after hepatectomy, while the control group was given saline after hepatectomy. Serum levels of aspartate aminotransferase and alanine aminotransferase and ...

  6. HDL activation of endothelial sphingosine-1-phosphate receptor-1 (S1P1) promotes regeneration and suppresses fibrosis in the liver

    DEFF Research Database (Denmark)

    Ding, Bi-Sen; Liu, Catherine H; Sun, Yue

    2016-01-01

    Regeneration of hepatic sinusoidal vasculature is essential for non-fibrotic liver regrowth and restoration of its metabolic capacity. However, little is known about how this specialized vascular niche is regenerated. Here we show that activation of endothelial sphingosine-1-phosphate receptor-1 ...

  7. Bone marrow-derived mesenchymal stem cells effectively regenerate fibrotic liver in bile duct ligation rat model.

    Science.gov (United States)

    Mohamed, Hoda E; Elswefy, Sahar E; Rashed, Laila A; Younis, Nahla N; Shaheen, Mohamed A; Ghanim, Amal M H

    2016-03-01

    Mesenchymal stem cells (MSCs) have attracted lots of attention for the treatment of acute liver failure and end-stage liver diseases. This study aimed at investigating the fundamental mechanism by which bone marrow-derived MSCs (BM-MSCs) induce liver regeneration of fibrotic liver in rats. Rats underwent bile duct ligation (BDL) surgery and four weeks later they were treated with either BM-MSCs (3 × 10(6) cells /rat, once, tail vein injection) or silymarin (100 mg/kg, daily, orally) for four weeks. Liver function tests and hepatic oxidative stress were determined. Hepatic injury and fibrosis were assessed by H and E, Sirus red staining and immunohistochemical expression of α-smooth muscle actin (α-SMA). Hepatocyte growth factor (HGF) and the gene expression of cytokeratin-19 (CK-19) and matrix metalloproteinase-2 (MMP-2) in liver tissue were determined. BDL induced cholestatic liver injury characterized by elevated ALT and AST activities, bilirubin and decreased albumin. The architecture damage was staged as Metavir score: F3, A3. Fibrosis increased around proliferating bile duct as indicated by sirus red staining and α-SMA immunostaining. Fibrogenesis was favored over fibrolysis and confirmed by decreased HGF with increased expression of CK-19, but decreased MMP-2 expression. BM-MSCs treatment restored deteriorated liver functions and restored the histological changes, resolved fibrosis by improving liver regenerative capabilities (P liver regenerative capabilities can be stimulated by BM-MSCs via augmentation of HGF that subsequently up-regulate MMP-2 mRNA while downregulating CK-19 mRNA. © 2016 by the Society for Experimental Biology and Medicine.

  8. Vitamin K2-enhanced liver regeneration is associated with oval cell expansion and up-regulation of matrilin-2 expression in 2-AAF/PH rat model.

    Science.gov (United States)

    Lin, M; Sun, P; Zhang, G; Xu, X; Liu, G; Miao, H; Yang, Y; Xu, H; Zhang, L; Wu, P; Li, M

    2014-03-01

    Normal liver has a great potential of regenerative capacity after partial hepatectomy. In clinic, however, most patients receiving partial hepatectomy are usually suffering from chronic liver diseases with severely damaged hepatocyte population. Under these conditions, activation of hepatic progenitor cell (oval cell in rodents) population might be considered as an alternative mean to enhance liver functional recovery. Vitamin K2 has been shown to promote liver functional recovery in patients with liver cirrhosis. In this study, we explored the possibility of vitamin K2 treatment in activating hepatic oval cell for liver regeneration with the classic 2-acetamido-fluorene/partial hepatectomy (2-AAF/PH) model in Sprague-Dawley rats. In 2-AAF/PH animals, vitamin K2 treatment induced a dose-dependent increase of liver regeneration as assessed by the weight ratio of remnant liver versus whole body and by measuring serum albumin level. In parallel, a drastic expansion of oval cell population as assessed by anti-OV6 and anti-CK19 immunostaining was noticed in the periportal zone of the remnant liver. Since matrilin-2 was linked to oval cell proliferation and liver regeneration after partial hepatectomy, we assessed its expression at both the mRNA and protein levels. The results revealed a significant increase after vitamin K2 treatment in parallel with the expansion of oval cell population. Consistently, knocking down matrilin-2 expression in vivo largely reduced vitamin K2-induced liver regeneration and oval cell proliferation in 2-AAF/PH animals. In conclusion, these data suggest that vitamin K2 treatment enhances liver regeneration after partial hepatectomy, which is associated with oval cell expansion and matrilin-2 up-regulation.

  9. HDL activation of endothelial sphingosine-1-phosphate receptor-1 (S1P1) promotes regeneration and suppresses fibrosis in the liver.

    Science.gov (United States)

    Ding, Bi-Sen; Liu, Catherine H; Sun, Yue; Chen, Yutian; Swendeman, Steven L; Jung, Bongnam; Chavez, Deebly; Cao, Zhongwei; Christoffersen, Christina; Nielsen, Lars Bo; Schwab, Susan R; Rafii, Shahin; Hla, Timothy

    2016-12-22

    Regeneration of hepatic sinusoidal vasculature is essential for non-fibrotic liver regrowth and restoration of its metabolic capacity. However, little is known about how this specialized vascular niche is regenerated. Here we show that activation of endothelial sphingosine-1-phosphate receptor-1 (S1P 1 ) by its natural ligand bound to HDL (HDL-S1P) induces liver regeneration and curtails fibrosis. In mice lacking HDL-S1P, liver regeneration after partial hepatectomy was impeded and associated with aberrant vascular remodeling, thrombosis and peri-sinusoidal fibrosis. Notably, this "maladaptive repair" phenotype was recapitulated in mice that lack S1P 1 in the endothelium. Reciprocally, enhanced plasma levels of HDL-S1P or administration of SEW2871, a pharmacological agonist specific for S1P 1 enhanced regeneration of metabolically functional vasculature and alleviated fibrosis in mouse chronic injury and cholestasis models. This study shows that natural and pharmacological ligands modulate endothelial S1P 1 to stimulate liver regeneration and inhibit fibrosis, suggesting that activation of this pathway may be a novel therapeutic strategy for liver fibrosis.

  10. Hepatic regeneration and functional recovery following partial liver resection in an experimental model of hepatic steatosis treated with omega-3 fatty acids

    NARCIS (Netherlands)

    Marsman, H. A.; de Graaf, W.; Heger, M.; van Golen, R. F.; ten Kate, F. J. W.; Bennink, R.; van Gulik, T. M.

    2013-01-01

    Omega-3 fatty acids (FAs) have been shown to reduce experimental hepatic steatosis and protect the liver from ischaemia-reperfusion injury. The aim of this study was to examine the effects of omega-3 FAs on regeneration of steatotic liver. Steatosis was induced in rats by a 3-week

  11. Expression of phosphatase of regenerating liver-3 is associated with prognosis of Wilms’ tumor

    Directory of Open Access Journals (Sweden)

    Sun F

    2017-01-01

    Full Text Available Fengyin Sun,1 Wenyi Li,2,3 Lie Wang,2 Changfeng Jiao3 1Department of Pediatric Surgery, Qilu Hospital, Shandong University, Jinan, Shandong Province, 2Department of General Surgery, Fuzhou General Hospital of Nanjing Command, PLA, Fuzhou, Fujian Province, 3Department of Vascular Surgery, Xinzhou City People’s Hospital, Xinzhou, Shanxi Province, People’s Republic of China Objective: The current study was undertaken to explore the clinical and prognostic value of phosphatase of regenerating liver-3 (PRL-3 expression in Wilms’ tumor. Methods: Seventy-six patients with Wilms’ tumor in Qilu Hospital from January 2003 to July 2009 were enrolled in the study. Protein expression level of PRL-3 was examined by immunohistochemical staining, and the correlation between PRL-3 expression and histopathological parameters, clinical variables, and outcome of patients with Wilms’ tumor were analyzed. Results: We found that 19% of patients with unfavorable histology had tumor recurrence and 16% of patients died following the operation. PRL-3 was expressed in 15 out of 76 tumors (19% and expressed highly in unfavorable histology Wilms’ tumor (P=0.04. PRL-3 protein expression level was correlated to 2.5-fold increase in recurrence rate of Wilms’ tumor (P=0.06 without any statistically significant difference. However, in favorable histology Wilms’ tumor, PRL-3 expression was correlated to an increase of 3.4-fold in recurrence rate (P=0.03. Conclusion: The expression of PRL-3 protein was correlated with an increased recurrence rate of favorable histology Wilms’ tumor. PRL-3 may serve as a promising biomarker for predicting patients with high risk of Wilms’ tumor. Further investigations are warranted to investigate the clinical function of PRL-3 in Wilms’ tumor. Keywords: Wilms’ tumor, prognosis, tumorigenesis, recurrence

  12. Biphasic activation of liver regeneration-associated signals in an early stage after portal vein branch ligation

    International Nuclear Information System (INIS)

    Yokoyama, Shinya; Yokoyama, Yukihiro; Kawai, Toru; Kobayashi, Satoshi; Nagino, Masato; Oda, Koji; Nimura, Yuji; Sokabe, Masahiro

    2006-01-01

    At an early stage in liver regeneration, a variety of factors including transcriptional factors, proinflammatory cytokines, and proto-oncogenes are activated or expressed. However, these responses are affected by surgical stress in the conventional portal vein branch ligation model (PVL). We sought to determine the net activation of early regeneration-associated signals after PVL using a newly developed non-surgical stress PVL model. Male Wistar rats were assigned into two groups, a stress-PVL (sPVL) model with laparotomy and portal vein branch ligation, and a non-stress-PVL (nsPVL) one subjected to portal vein branch ligation 1 week after laparotomy in which the effects of surgical stress were subsided. The activation of transcriptional factors and expression of immediate early genes were analyzed at an early time point (within 24 h) by Western blotting and RT-PCR, respectively. A monophasic upregulation of nuclear factor-κB (NF-κB) and phosphorylated-signal transducer and activator of transcription 3 (p-STAT3) peaked at 3 h after sPVL was observed. In contrast, the expression pattern of these factors was biphasic (first peak at 0.5-1 h, second peak at 3-6 h) in nsPVL group. The expression pattern of immediate early genes showed a similar trend between sPVL and nsPVL. cDNA array analysis for the non-ligated lobe at 2 h after PVL revealed a much higher gene activation in sPVL than in nsPVL. These results indicate that previously observed activation pattern of regeneration-associated signals after PVL is significantly affected by the effect of laparotomy and our results using nsPVL model may more accurately represent liver regeneration-associated signal pattern

  13. Liver fibrosis and regeneration in dogs and cats: An immunohistochemical approach

    NARCIS (Netherlands)

    IJzer, J.

    2008-01-01

    In this thesis we focus on liver tissue repair processes in canine and feline hepatitis, on formalin fixed paraffin embedded archival liver specimens. Hepatitis was diagnosed using histological standard criteria, and always includes hepatocellular cell death and an inflammatory infiltrate.

  14. Transplantation of Porcine Hepatocytes Cultured with Polylactic Acid-O-Carboxymethylated Chitosan Nanoparticles Promotes Liver Regeneration in Acute Liver Failure Rats

    Directory of Open Access Journals (Sweden)

    Zhong Chen

    2011-01-01

    Full Text Available In this study, free porcine hepatocytes suspension (Group A, porcine hepatocytes embedded in collagen gel (Group B, porcine hepatocytes cultured with PLA-O-CMC nanoparticles and embedded in collagen gel (Group C, and PLA-O-CMC nanoparticles alone (Group D were transplanted into peritoneal cavity of ALF rats, respectively. The result showed that plasma HGF levels were elevated post-transplantation with a peak at 12 hr. The rats in Group C showed highest plasma HGF levels at 2, 6, 12, 24 and 36 hr post-transplantation and lowest HGF level at 48 hr. Plasma VEGF levels were elevated at 48 hr post-transplantation with a peak at 72 hr. The rats in Group C showed highest plasma HGF levels at 48, 72, and 96 hr post-transplantation. The liver functions in Group C were recovered most rapidly. Compared with Group B, Group C had significant high liver Kiel 67 antigen labeling index (Ki-67 LI at day 1 post-HTx (P<.05. Ki-67 LI in groups B and C was higher than that in groups A and D at days 5 and 7 post-HTx. In conclusion, intraperitoneal transplantation of porcine hepatocytes cultured with PLA-O-CMC nanoparticles and embedded in collagen gel can promote significantly liver regeneration in ALF rats.

  15. Modeling Dynamics and Function of Bone Marrow Cells in Mouse Liver Regeneration

    NARCIS (Netherlands)

    Pedone, Elisa; Olteanu, Vlad-Aris; Marucci, Lucia; Muñoz-Martin, Maria Isabel; Youssef, Sameh A; de Bruin, Alain; Cosma, Maria Pia

    2017-01-01

    In rodents and humans, the liver can efficiently restore its mass after hepatectomy. This is largely attributed to the proliferation and cell cycle re-entry of hepatocytes. On the other hand, bone marrow cells (BMCs) migrate into the liver after resection. Here, we find that a block of BMC

  16. Inside out: high-efficiency plant regeneration and Agrobacterium-mediated transformation of upland and lowland switchgrass cultivars.

    Science.gov (United States)

    Liu, Yan-Rong; Cen, Hui-Fang; Yan, Jian-Ping; Zhang, Yun-Wei; Zhang, Wan-Jun

    2015-07-01

    Selection of pre-embryogenic callus from a core structure from mature seed-derived callus is the key for high-efficiency plant regeneration and transformation of switchgrass different cultivars. Switchgrass (Panicum virgatum L.) has been identified as a dedicated biofuel crop. For its trait improvement through biotechnological approaches, we have developed a highly efficient plant regeneration and genetic transformation protocol for both lowland and upland cultivars. We identified and separated a pre-embryogenic "core" structure from the seed-derived callus, which often leads to development of highly regenerative type II calluses. From the type II callus, plant regeneration rate of lowland cultivars Alamo and Performer reaches 95%, and upland cultivars Blackwell and Dacotah, 50 and 76%, respectively. The type II callus was also amenable for Agrobacterium-mediated transformation. Transformation efficiency of 72.8% was achieved for lowland cultivar Alamo, and 8.0% for upland cultivar Dacotah. PCR, Southern blot and GUS staining assays were performed to verify the transgenic events. High regenerative callus lines could be established in 3 months, and transgenic plants could be obtained in 2 months after Agrobacterium infection. To our knowledge, this is the first report on successful plant regeneration and recovery of transgenic plants from upland switchgrass cultivars by Agrobacterium-mediated transformation. The method presented here could be helpful in breaking through the bottleneck of regeneration and transformation of lowland and upland switchgrass cultivars and probably other recalcitrant grass crops.

  17. Agrobacterium-mediated transformation and direct shoot regeneration in Iranian tomato (Solanum lycopersicum L.) cultivar Falat- CH

    International Nuclear Information System (INIS)

    Kauser, N.; Khan, S.

    2016-01-01

    Falat CH is an important commercial tomato cultivar being used in Iran. In this article an optimized protocol with increased transformation and regeneration rate for this tomato variety is reported. Several explants including cotyledon, leaf and hypocotyl were evaluated for direct shoot formation and the effect of various combinations of BAP, Zeatin, IAA and IBA were studied. It is the first report on two cytokinins BAP and Zeatin in various combinations to evaluate the synergetic effect of cytokinins on direct shoot regeneration. The synergetic combination of 1.5mg/l BAP, 0.5 mg/l Zeatin and 0.2 mg/l IAA was considered as the best treatment which resulted in higher plant regeneration rates from all of the explants over previous reported methods. Using the best regeneration treatment obtained, the HBsAg gene was transferred into the tomato explants using Agrobacterium mediated transformation technique Percent of the putative transgenic plants regenerated was 68%. PCR of putative transformed plants showed that 87.1% of regenerated plants amplified nptII and HBsAg gene when specifically designed primers were used giving a final transformation rate of 34.85%. (author)

  18. Liver Regeneration After Portal Vein Embolization Using Absorbable and Permanent Embolization Materials in a Rabbit Model

    NARCIS (Netherlands)

    van den Esschert, Jacomina W.; van Lienden, Krijn P.; Alles, Lindy K.; van Wijk, Albert C.; Heger, Michal; Roelofs, Joris J.; van Gulik, Thomas M.

    2012-01-01

    Objective: To compare the safety and hypertrophy response after portal vein embolization (PVE) using 2 absorbable and 3 permanent embolization materials. Background: Portal vein embolization is used to increase future remnant liver volume preoperatively. Application of temporary, absorbable

  19. EGFR Activation Mediates Inhibition of Axon Regeneration by Myelin and Chondroitin Sulfate Proteoglycans

    Science.gov (United States)

    Koprivica, Vuk; Cho, Kin-Sang; Park, Jong Bae; Yiu, Glenn; Atwal, Jasvinder; Gore, Bryan; Kim, Jieun A.; Lin, Estelle; Tessier-Lavigne, Marc; Chen, Dong Feng; He, Zhigang

    2005-10-01

    Inhibitory molecules associated with myelin and the glial scar limit axon regeneration in the adult central nervous system (CNS), but the underlying signaling mechanisms of regeneration inhibition are not fully understood. Here, we show that suppressing the kinase function of the epidermal growth factor receptor (EGFR) blocks the activities of both myelin inhibitors and chondroitin sulfate proteoglycans in inhibiting neurite outgrowth. In addition, regeneration inhibitors trigger the phosphorylation of EGFR in a calcium-dependent manner. Local administration of EGFR inhibitors promotes significant regeneration of injured optic nerve fibers, pointing to a promising therapeutic avenue for enhancing axon regeneration after CNS injury.

  20. Integrative and comparative genomics analysis of early hepatocellular carcinoma differentiated from liver regeneration in young and old

    Directory of Open Access Journals (Sweden)

    Ozand Pinar T

    2010-06-01

    Full Text Available Abstract Background Hepatocellular carcinoma (HCC is the third-leading cause of cancer-related deaths worldwide. It is often diagnosed at an advanced stage, and hence typically has a poor prognosis. To identify distinct molecular mechanisms for early HCC we developed a rat model of liver regeneration post-hepatectomy, as well as liver cells undergoing malignant transformation and compared them to normal liver using a microarray approach. Subsequently, we performed cross-species comparative analysis coupled with copy number alterations (CNA of independent early human HCC microarray studies to facilitate the identification of critical regulatory modules conserved across species. Results We identified 35 signature genes conserved across species, and shared among different types of early human HCCs. Over 70% of signature genes were cancer-related, and more than 50% of the conserved genes were mapped to human genomic CNA regions. Functional annotation revealed genes already implicated in HCC, as well as novel genes which were not previously reported in liver tumors. A subset of differentially expressed genes was validated using quantitative RT-PCR. Concordance was also confirmed for a significant number of genes and pathways in five independent validation microarray datasets. Our results indicated alterations in a number of cancer related pathways, including p53, p38 MAPK, ERK/MAPK, PI3K/AKT, and TGF-β signaling pathways, and potential critical regulatory role of MYC, ERBB2, HNF4A, and SMAD3 for early HCC transformation. Conclusions The integrative analysis of transcriptional deregulation, genomic CNA and comparative cross species analysis brings new insights into the molecular profile of early hepatoma formation. This approach may lead to robust biomarkers for the detection of early human HCC.

  1. The Role of Innate Lymphoid Cells in Immune-Mediated Liver Diseases

    Science.gov (United States)

    Liu, Meifang; Zhang, Cai

    2017-01-01

    Innate lymphoid cells (ILCs) are a recently identified group of innate immune cells lacking antigen-specific receptors that can mediate immune responses and regulate tissue homeostasis and inflammation. ILCs comprise group 1 ILCs, group 2 ILCs, and group 3 ILCs. These ILCs usually localize at mucosal surfaces and combat pathogens by the rapid release of certain cytokines. However, the uncontrolled activation of ILCs can also lead to damaging inflammation, especially in the gut, lung, and skin. Although the physiological and pathogenic roles of ILCs in liver diseases have been attracting increasing attention recently, there has been no systematic review regarding the roles of ILCs in immune-mediated liver diseases. Here, we review the relationships between the ILC subsets and their functions in immune-mediated liver diseases, and discuss their therapeutic potential based on current knowledge about the functional roles of these cells in liver diseases. PMID:28659927

  2. Cytokines and Liver Diseases

    Directory of Open Access Journals (Sweden)

    Herbert Tilg

    2001-01-01

    Full Text Available Cytokines are pleiotropic peptides produced by virtually every nucleated cell in the body. In most tissues, including the liver, constitutive production of cytokines is absent or minimal. There is increasing evidence that several cytokines mediate hepatic inflammation, apoptosis and necrosis of liver cells, cholestasis and fibrosis. Interestingly, the same mediators also mediate the regeneration of liver tissue after injury. Among the various cytokines, the proinflammatory cytokine tumour necrosis factor-alpha (TNF-a has emerged as a key factor in various aspects of liver disease, such as cachexia and/or cholestasis. Thus, antagonism of TNF-a and other injury-related cytokines in liver diseases merits evaluation as a treatment of these diseases. However, because the same cytokines are also necessary for the regeneration of the tissue after the liver has been injured, inhibition of these mediators might impair hepatic recovery. The near future will bring the exiting clinical challenge of testing new anticytokine strategies in various liver diseases.

  3. Intraperitoneal exposure of whitefish to microcystin-LR induces rapid liver injury followed by regeneration and resilience to subsequent exposures

    International Nuclear Information System (INIS)

    Woźny, Maciej; Lewczuk, Bogdan; Ziółkowska, Natalia; Gomułka, Piotr; Dobosz, Stefan; Łakomiak, Alicja; Florczyk, Maciej; Brzuzan, Paweł

    2016-01-01

    To date, there has been no systematic approach comprehensively describing the sequence of pathological changes in fish during prolonged exposure to microcystin-LR (MC-LR). Towards this aim, juvenile whitefish individuals received an intraperitoneal injection with pure MC-LR, and the injection was repeated every week to maintain continuous exposure for 28 days. During the exposure period, growth and condition of the fish were assessed based on biometric measurements. Additionally, selected biochemical markers were analysed in the fishes' blood, and their livers were carefully examined for morphological, ultrastructural, and molecular changes. The higher dose of MC-LR (100 μg·kg −1 ) caused severe liver injury at the beginning of the exposure period, whereas the lower dose (10 μg·kg −1 ) caused less, probably reversible injury, and its effects began to be observed later in the exposure period. These marked changes were accompanied by substantial MC-LR uptake by the liver. However, starting on the 7th day of exposure, cell debris began to be removed by phagocytes, then by 14th day, proliferation of liver cells had markedly increased, which led to reconstruction of the liver parenchyma at the end of the treatment. Surprisingly, despite weekly-repeated intraperitoneal injections, MC-LR did not accumulate over time of exposure which suggests its limited uptake in the later phase of exposure. In support, mRNA expression of the membrane transport protein oatp1d was decreased at the same time as the regenerative processes were observed. Our study shows that closing of active membrane transport may serve as one defence mechanism against further MC-LR intoxication. - Highlights: • The study presents pathological changes in whitefish during prolonged MC-LR exposure. • After early, severe injury, the damaged liver parenchyma of the fish regenerated. • Endoplasmic reticulum, cytoskeleton, and chromatin were the main targets for MC-LR. • MC-LR did not

  4. Intraperitoneal exposure of whitefish to microcystin-LR induces rapid liver injury followed by regeneration and resilience to subsequent exposures

    Energy Technology Data Exchange (ETDEWEB)

    Woźny, Maciej, E-mail: maciej.wozny@uwm.edu.pl [Department of Environmental Biotechnology, Faculty of Environmental Sciences, University of Warmia and Mazury in Olsztyn, ul. Słoneczna 45G, 10-709 Olsztyn (Poland); Lewczuk, Bogdan; Ziółkowska, Natalia [Department of Histology and Embryology, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, ul. M. Oczapowskiego 13, 10-713 Olsztyn (Poland); Gomułka, Piotr [Department of Ichthyology, Faculty of Environmental Sciences, University of Warmia and Mazury in Olsztyn, ul. M. Oczapowskiego 5, 10-719 Olsztyn (Poland); Dobosz, Stefan [Department of the Salmonid Research in Rutki, Inland Fisheries Institute in Olsztyn, Rutki, 83-330 Żukowo (Poland); Łakomiak, Alicja; Florczyk, Maciej; Brzuzan, Paweł [Department of Environmental Biotechnology, Faculty of Environmental Sciences, University of Warmia and Mazury in Olsztyn, ul. Słoneczna 45G, 10-709 Olsztyn (Poland)

    2016-12-15

    To date, there has been no systematic approach comprehensively describing the sequence of pathological changes in fish during prolonged exposure to microcystin-LR (MC-LR). Towards this aim, juvenile whitefish individuals received an intraperitoneal injection with pure MC-LR, and the injection was repeated every week to maintain continuous exposure for 28 days. During the exposure period, growth and condition of the fish were assessed based on biometric measurements. Additionally, selected biochemical markers were analysed in the fishes' blood, and their livers were carefully examined for morphological, ultrastructural, and molecular changes. The higher dose of MC-LR (100 μg·kg{sup −1}) caused severe liver injury at the beginning of the exposure period, whereas the lower dose (10 μg·kg{sup −1}) caused less, probably reversible injury, and its effects began to be observed later in the exposure period. These marked changes were accompanied by substantial MC-LR uptake by the liver. However, starting on the 7th day of exposure, cell debris began to be removed by phagocytes, then by 14th day, proliferation of liver cells had markedly increased, which led to reconstruction of the liver parenchyma at the end of the treatment. Surprisingly, despite weekly-repeated intraperitoneal injections, MC-LR did not accumulate over time of exposure which suggests its limited uptake in the later phase of exposure. In support, mRNA expression of the membrane transport protein oatp1d was decreased at the same time as the regenerative processes were observed. Our study shows that closing of active membrane transport may serve as one defence mechanism against further MC-LR intoxication. - Highlights: • The study presents pathological changes in whitefish during prolonged MC-LR exposure. • After early, severe injury, the damaged liver parenchyma of the fish regenerated. • Endoplasmic reticulum, cytoskeleton, and chromatin were the main targets for MC-LR. • MC-LR did not

  5. Lentiviral-mediated transfer of CDNF promotes nerve regeneration and functional recovery after sciatic nerve injury in adult rats

    International Nuclear Information System (INIS)

    Cheng, Lei; Liu, Yi; Zhao, Hua; Zhang, Wen; Guo, Ying-Jun; Nie, Lin

    2013-01-01

    Highlights: •CDNF was successfully transfected by a lentiviral vector into the distal sciatic nerve. •CDNF improved S-100, NF200 expression and nerve regeneration after sciatic injury. •CDNF improved the remyelination and thickness of the regenerated sciatic nerve. •CDNF improved gastrocnemius muscle weight and sciatic functional recovery. -- Abstract: Peripheral nerve injury is often followed by incomplete and unsatisfactory functional recovery and may be associated with sensory and motor impairment of the affected limb. Therefore, a novel method is needed to improve the speed of recovery and the final functional outcome after peripheral nerve injuries. This report investigates the effect of lentiviral-mediated transfer of conserved dopamine neurotrophic factor (CDNF) on regeneration of the rat peripheral nerve in a transection model in vivo. We observed notable overexpression of CDNF protein in the distal sciatic nerve after recombinant CDNF lentiviral vector application. We evaluated sciatic nerve regeneration after surgery using light and electron microscopy and the functional recovery using the sciatic functional index and target muscle weight. HE staining revealed better ordered structured in the CDNF-treated group at 8 weeks post-surgery. Quantitative analysis of immunohistochemistry of NF200 and S-100 in the CDNF group revealed significant improvement of axonal and Schwann cell regeneration compared with the control groups at 4 weeks and 8 weeks after injury. The thickness of the myelination around the axons in the CDNF group was significantly higher than in the control groups at 8 weeks post-surgery. The CDNF group displayed higher muscle weights and significantly increased sciatic nerve index values. Our findings suggest that CDNF gene therapy could provide durable and stable CDNF protein concentration and has the potential to enhance peripheral nerve regeneration, morphological and functional recovery following nerve injury, which suggests a

  6. Lentiviral-mediated transfer of CDNF promotes nerve regeneration and functional recovery after sciatic nerve injury in adult rats

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Lei; Liu, Yi; Zhao, Hua; Zhang, Wen; Guo, Ying-Jun; Nie, Lin, E-mail: chengleiyx@126.com

    2013-10-18

    Highlights: •CDNF was successfully transfected by a lentiviral vector into the distal sciatic nerve. •CDNF improved S-100, NF200 expression and nerve regeneration after sciatic injury. •CDNF improved the remyelination and thickness of the regenerated sciatic nerve. •CDNF improved gastrocnemius muscle weight and sciatic functional recovery. -- Abstract: Peripheral nerve injury is often followed by incomplete and unsatisfactory functional recovery and may be associated with sensory and motor impairment of the affected limb. Therefore, a novel method is needed to improve the speed of recovery and the final functional outcome after peripheral nerve injuries. This report investigates the effect of lentiviral-mediated transfer of conserved dopamine neurotrophic factor (CDNF) on regeneration of the rat peripheral nerve in a transection model in vivo. We observed notable overexpression of CDNF protein in the distal sciatic nerve after recombinant CDNF lentiviral vector application. We evaluated sciatic nerve regeneration after surgery using light and electron microscopy and the functional recovery using the sciatic functional index and target muscle weight. HE staining revealed better ordered structured in the CDNF-treated group at 8 weeks post-surgery. Quantitative analysis of immunohistochemistry of NF200 and S-100 in the CDNF group revealed significant improvement of axonal and Schwann cell regeneration compared with the control groups at 4 weeks and 8 weeks after injury. The thickness of the myelination around the axons in the CDNF group was significantly higher than in the control groups at 8 weeks post-surgery. The CDNF group displayed higher muscle weights and significantly increased sciatic nerve index values. Our findings suggest that CDNF gene therapy could provide durable and stable CDNF protein concentration and has the potential to enhance peripheral nerve regeneration, morphological and functional recovery following nerve injury, which suggests a

  7. Ulk1-mediated autophagy plays an essential role in mitochondrial remodeling and functional regeneration of skeletal muscle.

    Science.gov (United States)

    Call, Jarrod A; Wilson, Rebecca J; Laker, Rhianna C; Zhang, Mei; Kundu, Mondira; Yan, Zhen

    2017-06-01

    Autophagy is a conserved cellular process for degrading aggregate proteins and dysfunctional organelle. It is still debatable if autophagy and mitophagy (a specific process of autophagy of mitochondria) play important roles in myogenic differentiation and functional regeneration of skeletal muscle. We tested the hypothesis that autophagy is critical for functional regeneration of skeletal muscle. We first observed time-dependent increases (3- to 6-fold) of autophagy-related proteins (Atgs), including Ulk1, Beclin1, and LC3, along with reduced p62 expression during C2C12 differentiation, suggesting increased autophagy capacity and flux during myogenic differentiation. We then used cardiotoxin (Ctx) or ischemia-reperfusion (I/R) to induce muscle injury and regeneration and observed increases in Atgs between days 2 and 7 in adult skeletal muscle followed by increased autophagy flux after day 7 Since Ulk1 has been shown to be essential for mitophagy, we asked if Ulk1 is critical for functional regeneration in skeletal muscle. We subjected skeletal muscle-specific Ulk1 knockout mice (MKO) to Ctx or I/R. MKO mice had significantly impaired recovery of muscle strength and mitochondrial protein content post-Ctx or I/R. Imaging analysis showed that MKO mice have significantly attenuated recovery of mitochondrial network at 7 and 14 days post-Ctx. These findings suggest that increased autophagy protein and flux occur during muscle regeneration and Ulk1-mediated mitophagy is critical for recovery for the mitochondrial network and hence functional regeneration. Copyright © 2017 the American Physiological Society.

  8. Acute Liver Allograft Antibody-Mediated Rejection: an inter-institutional study of routine histopathological features

    OpenAIRE

    O'Leary, Jacqueline G.; Shiller, S. Michelle; Bellamy, Christopher; Nalesnik, Michael A.; Kaneku, Hugo; Terasaki, Paul I.; Klintmalm, Göran B.; Demetris, Anthony J.

    2014-01-01

    Acute antibody-mediated rejection (AMR) occurs in a minority of sensitized liver transplant recipients. Although histopathologic characteristics have been described, a generalizable scoring system used to trigger a more in-depth analysis is needed to screen for this rare but important finding. Toward this goal, we created a training and validation cohort from 3 high volume liver transplant programs of putative acute AMR and control cases that were evaluated blindly by 4 independent transplant...

  9. Antibody-Mediated Osseous Regeneration for Bone Tissue Engineering in Canine Segmental Defects

    Directory of Open Access Journals (Sweden)

    A. Khojasteh

    2018-01-01

    Full Text Available Among many applications of therapeutic monoclonal antibodies (mAbs, a unique approach for regenerative medicine has entailed antibody-mediated osseous regeneration (AMOR. In an effort to identify a clinically relevant model of craniofacial defect, the present study investigated the efficacy of mAb specific for bone morphogenetic protein- (BMP- 2 to repair canine segmental mandibular continuity defect model. Accordingly, a 15 mm unilateral segmental defect was created in mandible and fixated with a titanium plate. Anorganic bovine bone mineral with 10% collagen (ABBM-C was functionalized with 25 μg/mL of either chimeric anti-BMP-2 mAb or isotype-matched mAb (negative control. Recombinant human (rh BMP-2 served as positive control. Morphometric analyses were performed on computed tomography (CT and histologic images. Bone densities within healed defect sites at 12 weeks after surgery were 1360.81 ± 10.52 Hounsfield Unit (HU, 1044.27 ± 141.16 HU, and 839.45 ± 179.41 HU, in sites with implanted anti-BMP-2 mAb, rhBMP-2, and isotype mAb groups, respectively. Osteoid bone formation in anti-BMP-2 mAb (42.99% ± 8.67 and rhBMP-2 (48.97% ± 2.96 groups was not significantly different but was higher (p<0.05 than in sites with isotype control mAb (26.8% ± 5.35. In view of the long-term objective of translational application of AMOR in humans, the results of the present study demonstrated the feasibility of AMOR in a large clinically relevant animal model.

  10. CD13 Promotes Mesenchymal Stem Cell-mediated regeneration of ischemic muscle

    Directory of Open Access Journals (Sweden)

    M. Mamunur eRahman

    2014-01-01

    Full Text Available Mesenchymal stem cells (MSCs are multipotent, tissue-resident cells that can facilitate tissue regeneration and thus show great promise as potential therapeutic agents. Functional MSCs have been isolated and characterized from a wide array of adult tissues and are universally identified by the shared expression of a core panel of MSCs markers. One of these markers is the multifunctional cell surface peptidase CD13 that has been shown to be expressed on human and murine MSCs from many tissues. To investigate whether this universal expression indicates a functional role for CD13 in MSC biology we isolated, expanded and characterized MSCs from bone marrow of wild type (WT and CD13KO mice. Characterization of these cells demonstrated that both WT and CD13KO MSCs expressed the full complement of MSC markers (CD29, CD44, CD49e, CD105, Sca1, showed comparable proliferation rates and were capable of differentiating toward the adipogenic and osteogenic lineages. However, MSCs lacking CD13 were unable to differentiate into vascular cells, consistent with our previous characterization of CD13 as an angiogenic regulator. Compared to WT MSCs, adhesion and migration on various extracellular matrices of CD13KO MSCs were significantly impaired, which correlated with decreased phospho-FAK levels and cytoskeletal alterations. Crosslinking human MSCs with activating CD13 antibodies increased cell adhesion to endothelial monolayers and induced FAK activation in a time dependent manner. In agreement with these in vitro data, intramuscular injection of CD13KO MSCs in a model of severe ischemic limb injury resulted in significantly poorer perfusion, decreased ambulation, increased necrosis and impaired vascularization compared to those receiving WT MSCs. This study suggests that CD13 regulates FAK activation to promote MSC adhesion and migration, thus contributing to MSC-mediated tissue repair. CD13 may present a viable target to enhance the efficacy of mesenchymal

  11. Advances in ultrasound-targeted microbubble-mediated gene therapy for liver fibrosis.

    Science.gov (United States)

    Huang, Cuiyuan; Zhang, Hong; Bai, Ruidan

    2017-07-01

    Hepatic fibrosis develops as a wound-healing scar in response to acute and chronic liver inflammation and can lead to cirrhosis in patients with chronic hepatitis B and C. The condition arises due to increased synthesis and reduced degradation of extracellular matrix (ECM) and is a common pathological sequela of chronic liver disease. Excessive deposition of ECM in the liver causes liver dysfunction, ascites, and eventually upper gastrointestinal bleeding as well as a series of complications. However, fibrosis can be reversed before developing into cirrhosis and has thus been the subject of extensive researches particularly at the gene level. Currently, therapeutic genes are imported into the damaged liver to delay or prevent the development of liver fibrosis by regulating the expression of exogenous genes. One technique of gene delivery uses ultrasound targeting of microbubbles combined with therapeutic genes where the time and intensity of the ultrasound can control the release process. Ultrasound irradiation of microbubbles in the vicinity of cells changes the permeability of the cell membrane by its cavitation effect and enhances gene transfection. In this paper, recent progress in the field is reviewed with emphasis on the following aspects: the types of ultrasound microbubbles, the construction of an ultrasound-mediated gene delivery system, the mechanism of ultrasound microbubble-mediated gene transfer and the application of ultrasound microbubbles in the treatment of liver fibrosis.

  12. Advances in ultrasound-targeted microbubble-mediated gene therapy for liver fibrosis

    Directory of Open Access Journals (Sweden)

    Cuiyuan Huang

    2017-07-01

    Full Text Available Hepatic fibrosis develops as a wound-healing scar in response to acute and chronic liver inflammation and can lead to cirrhosis in patients with chronic hepatitis B and C. The condition arises due to increased synthesis and reduced degradation of extracellular matrix (ECM and is a common pathological sequela of chronic liver disease. Excessive deposition of ECM in the liver causes liver dysfunction, ascites, and eventually upper gastrointestinal bleeding as well as a series of complications. However, fibrosis can be reversed before developing into cirrhosis and has thus been the subject of extensive researches particularly at the gene level. Currently, therapeutic genes are imported into the damaged liver to delay or prevent the development of liver fibrosis by regulating the expression of exogenous genes. One technique of gene delivery uses ultrasound targeting of microbubbles combined with therapeutic genes where the time and intensity of the ultrasound can control the release process. Ultrasound irradiation of microbubbles in the vicinity of cells changes the permeability of the cell membrane by its cavitation effect and enhances gene transfection. In this paper, recent progress in the field is reviewed with emphasis on the following aspects: the types of ultrasound microbubbles, the construction of an ultrasound-mediated gene delivery system, the mechanism of ultrasound microbubble–mediated gene transfer and the application of ultrasound microbubbles in the treatment of liver fibrosis.

  13. Postnatal liver growth and regeneration are independent of c-myc in a mouse model of conditional hepatic c-myc deletion

    Directory of Open Access Journals (Sweden)

    Sanders Jennifer A

    2012-03-01

    Full Text Available Abstract Background The transcription factor c-myc regulates genes involved in hepatocyte growth, proliferation, metabolism, and differentiation. It has also been assigned roles in liver development and regeneration. In previous studies, we made the unexpected observation that c-Myc protein levels were similar in proliferating fetal liver and quiescent adult liver with c-Myc displaying nucleolar localization in the latter. In order to investigate the functional role of c-Myc in adult liver, we have developed a hepatocyte-specific c-myc knockout mouse, c-mycfl/fl;Alb-Cre. Results Liver weight to body weight ratios were similar in control and c-myc deficient mice. Liver architecture was unaffected. Conditional c-myc deletion did not result in compensatory induction of other myc family members or in c-Myc's binding partner Max. Floxed c-myc did have a negative effect on Alb-Cre expression at 4 weeks of age. To explore this relationship further, we used the Rosa26 reporter line to assay Cre activity in the c-myc floxed mice. No significant difference in Alb-Cre activity was found between control and c-mycfl/fl mice. c-myc deficient mice were studied in a nonproliferative model of liver growth, fasting for 48 hr followed by a 24 hr refeeding period. Fasting resulted in a decrease in liver mass and liver protein, both of which recovered upon 24 h of refeeding in the c-mycfl/fl;Alb-Cre animals. There was also no effect of reducing c-myc on recovery of liver mass following 2/3 partial hepatectomy. Conclusions c-Myc appears to be dispensable for normal liver growth during the postnatal period, restoration of liver mass following partial hepatectomy and recovery from fasting.

  14. Hepatocyte Hypoxia Inducible Factor-1 Mediates the Development of Liver Fibrosis in a Mouse Model of Nonalcoholic Fatty Liver Disease.

    Directory of Open Access Journals (Sweden)

    Omar A Mesarwi

    Full Text Available Obstructive sleep apnea (OSA is associated with the progression of non-alcoholic fatty liver disease (NAFLD to steatohepatitis and fibrosis. This progression correlates with the severity of OSA-associated hypoxia. In mice with diet induced obesity, hepatic steatosis leads to liver tissue hypoxia, which worsens with exposure to intermittent hypoxia. Emerging data has implicated hepatocyte cell signaling as an important factor in hepatic fibrogenesis. We hypothesized that hepatocyte specific knockout of the oxygen sensing α subunit of hypoxia inducible factor-1 (HIF-1, a master regulator of the global response to hypoxia, may be protective against the development of liver fibrosis.Wild-type mice and mice with hepatocyte-specific HIF-1α knockout (Hif1a-/-hep were fed a high trans-fat diet for six months, as a model of NAFLD. Hepatic fibrosis was evaluated by Sirius red stain and hydroxyproline assay. Liver enzymes, fasting insulin, and hepatic triglyceride content were also assessed. Hepatocytes were isolated from Hif1a-/-hep mice and wild-type controls and were exposed to sustained hypoxia (1% O2 or normoxia (16% O2 for 24 hours. The culture media was used to reconstitute type I collagen and the resulting matrices were examined for collagen cross-linking.Wild-type mice on a high trans-fat diet had 80% more hepatic collagen than Hif1a-/-hep mice (2.21 μg collagen/mg liver tissue, versus 1.23 μg collagen/mg liver tissue, p = 0.03, which was confirmed by Sirius red staining. Body weight, liver weight, mean hepatic triglyceride content, and fasting insulin were similar between groups. Culture media from wild-type mouse hepatocytes exposed to hypoxia allowed for avid collagen cross-linking, but very little cross-linking was seen when hepatocytes were exposed to normoxia, or when hepatocytes from Hif1a-/-hep mice were used in hypoxia or normoxia.Hepatocyte HIF-1 mediates an increase in liver fibrosis in a mouse model of NAFLD, perhaps due to liver

  15. ICAM-1 triggers liver regeneration through leukocyte recruitment and Kupffer cell-dependent release of TNF-alpha/IL-6 in mice.

    NARCIS (Netherlands)

    Selzner, N; Selzner, M; Odermatt, B; Tian, Y; Rooijen, van N.; Clavien, PA

    2003-01-01

    AIMS: Tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 mediate hepatocyte proliferation in vivo, suggesting that local and systemic inflammatory reactions may trigger hepatic regeneration after major tissue loss. METHODS: Wild-type, intercellular adhesion molecule (ICAM)-1-/-, and

  16. Kinetics of /sup 3/H-thymidine incorporation into nuclei of cells of the regenerating liver of rats exposed to various doses of x rays

    Energy Technology Data Exchange (ETDEWEB)

    Aksenovich, T I; Polishchuk, A M [AN SSSR, Novosibirsk. Inst. Tsitologii i Genetiki

    1976-01-01

    Action of x radiation on the incorporation of /sup 3/H-thymidine into nuclei of cells of the regenerating liver of rats has been studied. A whole-body exposure of rats to 150 to 300 R has been found to inhibit /sup 3/H-thymidine uptake into DNA of S-cells of the regenerating liver, and this effect can be attributed to the inhibition of DNA synthesis rather than to changes in the concentration of a label in the intracellular pool of DNA precursors. In addition to the DNA synthesis decrease, inhibition of the label uptake into the pool is observed after doses of 600 to 1200 R. On the basis of the data obtained, a hypothesis is proposed that explains the mechanism of inhibition of DNA synthesis under the action of radiation.

  17. Temporal mapping of CEBPA and CEBPB binding during liver regeneration reveals dynamic occupancy and specific regulatory codes for homeostatic and cell cycle gene batteries

    DEFF Research Database (Denmark)

    Jakobsen, Janus Schou; Waage, Johannes; Rapin, Nicolas

    2013-01-01

    quantified the genome-wide binding patterns of two key hepatocyte transcription factors, CEBPA and CEBPB (also known as C/EBPalpha and C/EBPbeta), at multiple time points during the highly dynamic process of liver regeneration elicited by partial hepatectomy in mouse. Combining these profiles with RNA...... polymerase II binding data, we find three temporal classes of transcription factor binding to be associated with distinct sets of regulated genes involved in the acute phase response, metabolic/homeostatic functions, or cell cycle progression. Moreover, we demonstrate a previously unrecognized early phase......IP experiments involving a panel of central transcription factors and/or by comparison to external ChIP-seq data. Our quantitative investigation not only provides in vivo evidence for the involvement of many new factors in liver regeneration but also points to similarities in the circuitries regulating self...

  18. A morphometric study on regeneration of the human liver following hepatectomy by computed tomography

    International Nuclear Information System (INIS)

    Okamoto, Eizo; Yamanaka, Naoki

    1983-01-01

    A morphometric study has been carried out on the restoration of remnant hepatic volume (RHV) after various extent of hepatectomy in humans by serial computed tomography in 15 non-cirrhotics, 14 cirrhotics and 7 hepatic failures. Restoration of RHV has been observed only in patients with more than 10 % hepatectomy. In non-cirrhotics with major hepatectomy (RHV less than 600 cm 3 ), an early rapid increasing phase was followed by a subsequent decreasing phase and then a slow increasing phase. Decreasing phase was absent in most non-cirrhotics with moderate hepatectomy (RHV 600-1000 cm 3 ) and cirrhotics. Daily increase rate of RHV during the first posthepatectomy month was inversely proportional to the RHV at operation restoring invariably to 800-900 cm 3 at the end of this month. Termination of regeneration was within 6 months in non-cirrhotics with moderate hepatectomy and from 6 to 12 months in those with major hepatectomy. It was delayed in cirrhotics. RHV has finally attained to an average of 90 % of preoperative hepatic volume in non-cirrhotics and 81 % in cirrhotics. The restoration of RHV was extremely poor in hepatic failures. (author)

  19. Transcriptional switch from albumin to alpha-fetoprotein and changes in transcription of other genes during carbon tetrachloride induced liver regeneration

    International Nuclear Information System (INIS)

    Panduro, A.; Shalaby, F.; Weiner, F.R.; Biempica, L.; Zern, M.A.; Shafritz, D.A.

    1986-01-01

    During liver regeneration induced by CCl 4 administration to rats, changes in the relative transcription rates of albumin and alpha-fetoprotein genes have been measured in conjunction with other liver-specific and general cellular function genes. Within 24 h following CCl 4 administration, albumin gene transcription decreases by 85%, whereas alpha-fetoprotein transcription increases from undetectable levels to 50% of that observed for albumin. These changes precede maximal [ 3 H]thymidine incorporation into DNA which peaks at 48 h. Other genes related to liver-specific functions, such as ligandin, alpha 1-antitrypsin, and cytochrome P-450's, as well as general cellular genes pro alpha 1- and pro alpha 2-collagen, beta-actin, and alpha-tubulin, respond in kinetic patterns often distinct from each other and from albumin and alpha-fetoprotein. Changes in the steady-state levels of albumin and alpha-fetoprotein mRNA correlate with changes in transcription, but there is a lag in alpha-fetoprotein mRNA accumulation, which peaks at 72 h following CCl 4 administration. These studies indicate that reciprocal changes in albumin and alpha-fetoprotein gene transcription occur during CCl 4 -induced liver regeneration, leading to changes in the level of these specific mRNAs. These changes precede DNA synthesis and would appear to represent an alteration in differentiated function of hepatocytes in conjunction with the liver regenerative process

  20. Disruptive cell cycle regulation involving epigenetic downregulation of Cdkn2a (p16Ink4a) in early-stage liver tumor-promotion facilitating liver cell regeneration in rats

    International Nuclear Information System (INIS)

    Tsuchiya, Takuma; Wang, Liyun; Yafune, Atsunori; Kimura, Masayuki; Ohishi, Takumi; Suzuki, Kazuhiko; Mitsumori, Kunitoshi; Shibutani, Makoto

    2012-01-01

    Cell cycle aberration was immunohistochemically examined in relation to preneoplastic liver cell foci expressing glutathione S-transferase placental form (GST-P) at early stages of tumor-promotion in rats with thioacetamide (TAA), a hepatocarcinogen facilitating liver cell regeneration. Immunoexpression of p16 Ink4a following exposure to other hepatocarcinogens/promoters and its DNA methylation status were also analyzed during early and late tumor-promotion stages. GST-P + liver cell foci increased cell proliferation and decreased apoptosis when compared with surrounding liver cells. In concordance with GST-P + foci, checkpoint proteins at G 1 /S (p21 Cip1 , p27 Kip1 and p16 Ink4a ) and G 2 /M (phospho-checkpoint kinase 1, Cdc25c and phospho-Wee1) were either up- or downregulated. Cellular distribution within GST-P + foci was either increased or decreased with proteins related to G 2 -M phase or DNA damage (topoisomerase IIα, phospho-histone H2AX, phospho-histone H3 and Cdc2). In particular, p16 Ink4a typically downregulated in GST-P + foci and regenerative nodules at early tumor-promotion stage with hepatocarcinogens facilitating liver cell regeneration and in neoplastic lesions at late tumor-promotion stage with hepatocarcinogens/promoters irrespective of regenerating potential. Hypermethylation at exon 2 of Cdkn2a was detected at both early- and late-stages. Thus, diverse disruptive expression of G 1 /S and G 2 /M proteins, which allows for clonal selection of GST-P + foci, results in the acquisition of multiple aberrant phenotypes to disrupt checkpoint function. Moreover, increased DNA-damage responses within GST-P + foci may be the signature of genetic alterations. Intraexonic hypermethylation may be responsible for p16 Ink4a -downregulation, which facilitates cell cycle progression in early preneoplastic lesions produced by repeated cell regeneration and late-stage neoplastic lesions irrespective of the carcinogenic mechanism.

  1. Downregulation of IL6 Targeted MiR-376b May Contribute to a Positive IL6 Feedback Loop During Early Liver Regeneration in Mice

    Directory of Open Access Journals (Sweden)

    Shan Lu

    2015-08-01

    Full Text Available Background/Aims: MicroRNAs (miRNAs are a group of endogenous, small, noncoding RNAs implicated in a variety of biological processes, including cell proliferation, apoptosis, differentiation and metabolism. The present study aims to explore the potential role and molecular mechanism of miR-376b during the early phase of liver regeneration. Methods: MiRNA profiling microarrays were used to assess the changes in miRNA expression. For functional analysis, cell proliferation, apoptosis assays, real time quantitative PCR and westernblot analysis were performed. Results: The comprehensive miRNA expression profiling assays on regenerating liver tissues 4 h after partial hepatectomy (PH showed that three miRNAs (miR-127, miR-376b and miR-494 located in the Dlk1-Gtl2 miRNA cluster were significantly downregulated. In vitro functional studies demonstrated that high-level interleukin 6 (IL6 inhibited the expression of miR-376b, and miR-376b mimics treatment decreased cell proliferation and increased apoptosis. Further target analysis showed that miR-376b reduced the mRNA and protein expression levels of NF-kappa-B inhibitor zeta (NFKBIZ and signal transducers and transcription activators 3 (STAT3. Additionally, IL6-induced miR-376b downregulation would, in turn, increase the expression of IL-6 possibly via a feedback loop involving NFKBIZ or/and STAT3. Conclusion: During the early phase of liver regeneration, miR-376b expression was significantly decreased. Our findings reveal that a regulatory circuitry between miR-376b and IL-6 may exist, which trigger the initiation of liver regeneration.

  2. Transcriptomic and Hormonal Analyses Reveal that YUC-Mediated Auxin Biogenesis Is Involved in Shoot Regeneration from Rhizome in Cymbidium.

    Science.gov (United States)

    Liu, Yang; Zhang, Hai-Liang; Guo, He-Rong; Xie, Li; Zeng, Rui-Zhen; Zhang, Xiang-Qian; Zhang, Zhi-Sheng

    2017-01-01

    Cymbidium , one of the most important orchid genera in horticulture, can be classified into epiphytic and terrestrial species. Generally, epiphytic Cymbidium seedlings can be easily propagated by tissue culture, but terrestrial seedlings are difficult to propagate. To date, the molecular mechanisms underlying the differences in the ease with which terrestrial and epiphytic cymbidiums can be propagated are largely unknown. Using RNA-sequencing, quantitative reverse transcription PCR and enzyme-linked immunosorbent assay, Cymbidium 'Xiaofeng' (CXF), which can be efficiently micropropagated, and terrestrial Cymbidium sinense 'Qijianbaimo' (CSQ), which has a low regeneration ability, were used to explore the molecular mechanisms underlying the micropropagation ability of Cymbidium species. To this end, 447 million clean short reads were generated, and 31,264 annotated unigenes were obtained from 10 cDNA libraries. A total of 1,290 differentially expressed genes (DEGs) were identified between CXF and CSQ during shoot induction. Gene ontology (GO) enrichment analysis indicated that the DEGs were significantly enriched in auxin pathway-related GO terms. Further analysis demonstrated that YUC and GH3 family genes, which play crucial roles in the regulation of auxin/IAA (indole-3-acetic acid) metabolism, acted quickly in response to shoot induction culture in vitro and were closely correlated with variation in shoot regeneration between CXF and CSQ. In addition, the study showed that IAA accumulated rapidly and significantly during shoot induction in CXF compared to that in CSQ; in contrast, no significant changes in other hormones were observed between CXF and CSQ. Furthermore, shoot regeneration in CXF was inhibited by a yucasin-auxin biosynthesis inhibitor, indicating that increased IAA level is required for high-frequency shoot regeneration in CXF. In conclusion, our study revealed that YUC-mediated auxin biogenesis is involved in shoot regeneration from rhizome in

  3. Transcriptomic and Hormonal Analyses Reveal that YUC-Mediated Auxin Biogenesis Is Involved in Shoot Regeneration from Rhizome in Cymbidium

    Directory of Open Access Journals (Sweden)

    Yang Liu

    2017-10-01

    Full Text Available Cymbidium, one of the most important orchid genera in horticulture, can be classified into epiphytic and terrestrial species. Generally, epiphytic Cymbidium seedlings can be easily propagated by tissue culture, but terrestrial seedlings are difficult to propagate. To date, the molecular mechanisms underlying the differences in the ease with which terrestrial and epiphytic cymbidiums can be propagated are largely unknown. Using RNA-sequencing, quantitative reverse transcription PCR and enzyme-linked immunosorbent assay, Cymbidium ‘Xiaofeng’ (CXF, which can be efficiently micropropagated, and terrestrial Cymbidium sinense ‘Qijianbaimo’ (CSQ, which has a low regeneration ability, were used to explore the molecular mechanisms underlying the micropropagation ability of Cymbidium species. To this end, 447 million clean short reads were generated, and 31,264 annotated unigenes were obtained from 10 cDNA libraries. A total of 1,290 differentially expressed genes (DEGs were identified between CXF and CSQ during shoot induction. Gene ontology (GO enrichment analysis indicated that the DEGs were significantly enriched in auxin pathway-related GO terms. Further analysis demonstrated that YUC and GH3 family genes, which play crucial roles in the regulation of auxin/IAA (indole-3-acetic acid metabolism, acted quickly in response to shoot induction culture in vitro and were closely correlated with variation in shoot regeneration between CXF and CSQ. In addition, the study showed that IAA accumulated rapidly and significantly during shoot induction in CXF compared to that in CSQ; in contrast, no significant changes in other hormones were observed between CXF and CSQ. Furthermore, shoot regeneration in CXF was inhibited by a yucasin-auxin biosynthesis inhibitor, indicating that increased IAA level is required for high-frequency shoot regeneration in CXF. In conclusion, our study revealed that YUC-mediated auxin biogenesis is involved in shoot

  4. TIMP3 deficiency exacerbates iron overload-mediated cardiomyopathy and liver disease.

    Science.gov (United States)

    Zhabyeyev, Pavel; Das, Subhash K; Basu, Ratnadeep; Shen, Mengcheng; Patel, Vaibhav B; Kassiri, Zamaneh; Oudit, Gavin Y

    2018-05-01

    Chronic iron overload results in heart and liver diseases and is a common cause of morbidity and mortality in patients with genetic hemochromatosis and secondary iron overload. We investigated the role of tissue inhibitor of metalloproteinase 3 (TIMP3) in iron overload-mediated tissue injury by subjecting male mice lacking Timp3 ( Timp3 -/- ) and wild-type (WT) mice to 12 wk of chronic iron overload. Whereas WT mice with iron overload developed diastolic dysfunction, iron-overloaded Timp3 -/- mice showed worsened cardiac dysfunction coupled with systolic dysfunction. In the heart, loss of Timp3 was associated with increased myocardial fibrosis, greater Timp1, matrix metalloproteinase ( Mmp) 2, and Mmp9 expression, increased active MMP-2 levels, and gelatinase activity. Iron overload in Timp3 -/- mice showed twofold higher iron accumulation in the liver compared with WT mice because of constituently lower levels of ferroportin. Loss of Timp3 enhanced the hepatic inflammatory response to iron overload, leading to greater neutrophil and macrophage infiltration and increased hepatic fibrosis. Expression of inflammation-related MMPs (MMP-12 and MMP-13) and inflammatory cytokines (IL-1β and monocyte chemoattractant protein-1) was elevated to a greater extent in iron-overloaded Timp3 -/- livers. Gelatin zymography demonstrated equivalent increases in MMP-2 and MMP-9 levels in WT and Timp3 -/- iron-overloaded livers. Loss of Timp3 enhanced the susceptibility to iron overload-mediated heart and liver injury, suggesting that Timp3 is a key protective molecule against iron-mediated pathology. NEW & NOTEWORTHY In mice, loss of tissue inhibitor of metalloproteinase 3 ( Timp3) was associated with systolic and diastolic dysfunctions, twofold higher hepatic iron accumulation (attributable to constituently lower levels of ferroportin), and increased hepatic inflammation. Loss of Timp3 enhanced the susceptibility to iron overload-mediated injury, suggesting that Timp3 plays a key

  5. Maresin 1, a Proresolving Lipid Mediator, Mitigates Carbon Tetrachloride-Induced Liver Injury in Mice

    Directory of Open Access Journals (Sweden)

    Ruidong Li

    2016-01-01

    Full Text Available Maresin 1 (MaR 1 was recently reported to have protective properties in several different animal models of acute inflammation by inhibiting inflammatory response. However, its function in acute liver injury is still unknown. To address this question, we induced liver injury in BALB/c mice with intraperitoneal injection of carbon tetrachloride with or without treatment of MaR 1. Our data showed that MaR 1 attenuated hepatic injury, oxidative stress, and lipid peroxidation induced by carbon tetrachloride, as evidenced by increased thiobarbituric acid reactive substances and reactive oxygen species levels were inhibited by treatment of MaR 1. Furthermore, MaR 1 increased activities of antioxidative mediators in carbon tetrachloride-treated mice liver. MaR 1 decreased indices of inflammatory mediators such as tumor necrosis factor-α, interleukin-6, interleukin-1β, monocyte chemotactic protein 1, myeloperoxidase, cyclooxygenase-2, and inducible nitric oxide synthase. Administration of MaR 1 inhibited activation of nuclear factor kappa B (NF-κb and mitogen-activated protein kinases (MAPKs in the liver of CCl4 treated mice. In conclusion, these results suggested the antioxidative, anti-inflammatory properties of MaR 1 in CCl4 induced liver injury. The possible mechanism is partly implicated in its abilities to inhibit ROS generation and activation of NF-κb and MAPK pathway.

  6. Fasting enhances TRAIL-mediated liver natural killer cell activity via HSP70 upregulation.

    Directory of Open Access Journals (Sweden)

    Vu T A Dang

    Full Text Available Acute starvation, which is frequently observed in clinical practice, sometimes augments the cytolytic activity of natural killer cells against neoplastic cells. In this study, we investigated the molecular mechanisms underlying the enhancement of natural killer cell function by fasting in mice. The total number of liver resident natural killer cells in a unit weight of liver tissue obtained from C57BL/6J mice did not change after a 3-day fast, while the proportions of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL+ and CD69+ natural killer cells were significantly elevated (n = 7, p <0.01, as determined by flow cytometric analysis. Furthermore, we found that TRAIL- natural killer cells that were adoptively transferred into Rag-2-/- γ chain-/- mice could convert into TRAIL+ natural killer cells in fasted mice at a higher proportion than in fed mice. Liver natural killer cells also showed high TRAIL-mediated antitumor function in response to 3-day fasting. Since these fasted mice highly expressed heat shock protein 70 (n = 7, p <0.05 in liver tissues, as determined by western blot, the role of this protein in natural killer cell activation was investigated. Treatment of liver lymphocytes with 50 µg/mL of recombinant heat shock protein 70 led to the upregulation of both TRAIL and CD69 in liver natural killer cells (n = 6, p <0.05. In addition, HSP70 neutralization by intraperitoneally injecting an anti- heat shock protein 70 monoclonal antibody into mice prior to fasting led to the downregulation of TRAIL expression (n = 6, p <0.05. These findings indicate that acute fasting enhances TRAIL-mediated liver natural killer cell activity against neoplastic cells through upregulation of heat shock protein 70.

  7. Long-range neural and gap junction protein-mediated cues control polarity during planarian regeneration

    NARCIS (Netherlands)

    Morokuma, Junji; Oviedo, Nestor J.; Walentek, Peter; Kema, Ido P.; Gu, Man Bock; Ahn, Joo-Myung; Hwang, Jung Shan; Gojobori, Takashi; Levin, Michael

    2010-01-01

    Having the ability to coordinate the behavior of stem cells to induce regeneration of specific large-scale structures would have far-reaching consequences in the treatment of degenerative diseases, acute injury, and aging. Thus, identifying and learning to manipulate the sequential steps that

  8. Engraftment and reconstitution of hematopoiesis is dependent on VEGFR2 mediated regeneration of sinusoidal endothelial cells

    Science.gov (United States)

    Hooper, Andrea T.; Butler, Jason M.; Nolan, Daniel J; Kranz, Andrea; Iida, Kaoruko; Kobayashi, Mariko; Kopp, Hans-Georg; Shido, Koji; Petit, Isabelle; Yanger, Kilangsungla; James, Daylon; Witte, Larry; Zhu, Zhenping; Wu, Yan; Pytowski, Bronislaw; Rosenwaks, Zev; Mittal, Vivek; Sato, Thomas N.; Rafii, Shahin

    2011-01-01

    SUMMARY The phenotypic attributes and molecular determinants for the regeneration of bone marrow (BM) sinusoidal endothelial cells (SECs) and their contribution to hematopoiesis are unknown. We show that after myelosuppression VEGFR2 activation promotes reassembly of regressed SECs, reconstituting hematopoietic stem and progenitor cells (HSPCs). VEGFR2 and VEGFR3 expression are restricted to BM vasculature, demarcating a continuous network of VEGFR2+VEGFR3+Sca1− SECs and VEGFR2+VEGFR3−Sca1+ arterioles. While chemotherapy (5FU) and sublethal irradiation (650 rad) induce minor SEC regression, lethal irradiation (950 rad) induces severe regression of SECs requiring BM transplantation (BMT) for regeneration. Conditional deletion of VEGFR2 in adult mice blocks regeneration of SECs in sublethally irradiated animals, preventing hematopoietic reconstitution. Inhibition of VEGFR2 signaling in lethally irradiated wild type mice rescued with BMT severely impairs SEC reconstruction, preventing engraftment and reconstitution of HSPCs. Therefore, activation of VEGFR2 is critical for regeneration of VEGFR3+Sca1− SECs that are essential for engraftment and restoration of HSPCs and hematopoiesis. PMID:19265665

  9. Adenovirus-mediated transfer of hepatocyte growth factor gene to human dental pulp stem cells under good manufacturing practice improves their potential for periodontal regeneration in swine.

    Science.gov (United States)

    Cao, Yu; Liu, Zhenhai; Xie, Yilin; Hu, Jingchao; Wang, Hua; Fan, Zhipeng; Zhang, Chunmei; Wang, Jingsong; Wu, Chu-Tse; Wang, Songlin

    2015-12-15

    Periodontitis is one of the most widespread infectious diseases in humans. We previously promoted significant periodontal tissue regeneration in swine models with the transplantation of autologous periodontal ligament stem cells (PDLSCs) and PDLSC sheet. We also promoted periodontal tissue regeneration in a rat model with a local injection of allogeneic bone marrow mesenchymal stem cells. The purpose of the present study is to investigate the roles of the hepatocyte growth factor (HGF) and human dental pulp stem cells (DPSCs) in periodontal tissue regeneration in swine. In the present study, we transferred an adenovirus that carried HGF gene into human DPSCs (HGF-hDPSCs) under good manufacturing practice (GMP) conditions. These cells were then transplanted into a swine model for periodontal regeneration. Twenty miniature pigs were used to generate periodontitis with bone defect of 5 mm in width, 7 mm in length, and 3 mm in depth. After 12 weeks, clinical, radiological, quantitative and histological assessment of regenerated periodontal tissues was performed to compare periodontal regeneration in swine treated with cell implantation. Our study showed that injecting HGF-hDPSCs into this large animal model could significantly improve periodontal bone regeneration and soft tissue healing. A hDPSC or HGF-hDPSC sheet showed superior periodontal tissue regeneration compared to the injection of dissociated cells. However, the sheets required surgical placement; thus, they were suitable for surgically-managed periodontitis treatments. The adenovirus-mediated transfer of the HGF gene markedly decreased hDPSC apoptosis in a hypoxic environment or in serum-free medium, and it increased blood vessel regeneration. This study indicated that HGF-hDPSCs produced under GMP conditions significantly improved periodontal bone regeneration in swine; thus, this method represents a potential clinical application for periodontal regeneration.

  10. Regeneration of hyaline cartilage by cell-mediated gene therapy using transforming growth factor beta 1-producing fibroblasts.

    Science.gov (United States)

    Lee, K H; Song, S U; Hwang, T S; Yi, Y; Oh, I S; Lee, J Y; Choi, K B; Choi, M S; Kim, S J

    2001-09-20

    Transforming growth factor beta (TGF-beta) has been considered as a candidate for gene therapy of orthopedic diseases. The possible application of cell-mediated TGF-beta gene therapy as a new treatment regimen for degenerative arthritis was investigated. In this study, fibroblasts expressing active TGF-beta 1 were injected into the knee joints of rabbits with artificially made cartilage defects to evaluate the feasibility of this therapy for orthopedic diseases. Two to 3 weeks after the injection there was evidence of cartilage regeneration, and at 4 to 6 weeks the cartilage defect was completely filled with newly grown hyaline cartilage. Histological analyses of the regenerated cartilage suggested that it was well integrated with the adjacent normal cartilage at the sides of the defect and that the newly formed tissue was indeed hyaline cartilage. Our findings suggest that cell-mediated TGF-beta 1 gene therapy may be a novel treatment for orthopedic diseases in which hyaline cartilage damage has occurred.

  11. Cutting Edge: Eosinophils Undergo Caspase-1-Mediated Pyroptosis in Response to Necrotic Liver Cells.

    Science.gov (United States)

    Palacios-Macapagal, Daphne; Connor, Jane; Mustelin, Tomas; Ramalingam, Thirumalai R; Wynn, Thomas A; Davidson, Todd S

    2017-08-01

    Many chronic liver disorders are characterized by dysregulated immune responses and hepatocyte death. We used an in vivo model to study the immune response to necrotic liver injury and found that necrotic liver cells induced eosinophil recruitment. Necrotic liver induced eosinophil IL-1β and IL-18 secretion, degranulation, and cell death. Caspase-1 inhibitors blocked all of these responses. Caspase-1-mediated cell death with accompanying cytokine release is the hallmark of a novel form of cell death termed pyroptosis. To confirm this response in a disease model, we isolated eosinophils from the livers of Schistosoma mansoni -infected mice. S. mansoni eggs lodge in the hepatic sinusoids of infected mice, resulting in hepatocyte death, inflammation, and progressive liver fibrosis. This response is typified by massive eosinophilia, and we were able to confirm pyroptosis in the infiltrating eosinophils. This demonstrated that pyroptosis is a cellular pathway used by eosinophils in response to large-scale hepatic cell death. Copyright © 2017 by The American Association of Immunologists, Inc.

  12. Suppression of immune-mediated liver injury after vaccination with attenuated pathogenic cells.

    Science.gov (United States)

    Mei, Yunhua; Wang, Ying; Xu, Lingyun

    2007-05-15

    Cell vaccination via immunization with attenuated pathogenic cells is an effective preventive method that has been successfully applied in several animal models of inflammatory or autoimmune diseases. Concanavalin A (Con A)-induced hepatitis (CIH) is a commonly used experimental model to study immune-mediated liver injury. Multiple cell types including T lymphocytes, macrophages and neutrophils have been found to be involved in the pathogenesis of CIH. In this study, we used attenuated spleen lymphocytes or peripheral blood lymphocytes as vaccines to investigate whether they could induce protective immune responses to prevent mice from developing CIH. We found that mice receiving such vaccination before CIH induction developed much milder diseases, exhibited a lower level of alanine aminotransferase (ALT) released into their plasma and had less inflammatory lesions in their livers. Such CIH-suppression is dose- and frequency-dependent. The suppressive effect was associated with inhibition of several major inflammatory mediators, pro-inflammatory cytokines and chemokines.

  13. SET mediates TCE-induced liver cell apoptosis through dephosphorylation and upregulation of nucleolin.

    Science.gov (United States)

    Ren, Xiaohu; Huang, Xinfeng; Yang, Xifei; Liu, Yungang; Liu, Wei; Huang, Haiyan; Wu, Desheng; Zou, Fei; Liu, Jianjun

    2017-06-20

    Trichloroethylene (TCE) is an occupational and environmental chemical that can cause severe hepatotoxicity. While our previous studies showed that the phosphatase inhibitor SET is a key mediator of TCE-induced liver cell apoptosis, the molecular mechanisms remain elusive. Using quantitative phosphoproteomic analysis, we report here that nucleolin is a SET-regulated phosphoprotein in human liver HL-7702 cells. Functional analysis suggested that SET promoted dephosphorylation of nucleolin, decreased its binding to its transcriptional activator, c-myc, and upregulated nucleolin expression in TCE-treated cells. Importantly, TCE-induced hepatocyte apoptosis was significantly attenuated when nucleolin was downregulated with specific siRNAs. These findings indicate that TCE may induce hepatocyte apoptosis via SET-mediated dephosphorylation and overexpression of nucleolin.

  14. Asynchronous Inflammation and Myogenic Cell Migration Limit Muscle Tissue Regeneration Mediated by a Cellular Scaffolds

    Science.gov (United States)

    2015-02-11

    such as duchenne muscular dystrophy ) results in impaired regeneration, increased atrophy and fibrosis of skeletal muscle [24-27]. It has also been...2005; 122:289-301. 24. Cohn RDCampbell KP. Molecular basis of muscular dystrophies . Muscle Nerve 2000; 23:1456-1471. 25. Morgan JEZammit PS. Direct...et al. Early onset of inflammation and later involvement of TGFbeta in Duchenne muscular dystrophy . Neurology 2005; 65:826-834. 28. Lepper C

  15. Biomimetic extracellular matrix mediated somatic stem cell differentiation: applications in dental pulp tissue regeneration

    Science.gov (United States)

    Ravindran, Sriram; George, Anne

    2015-01-01

    Dental caries is one of the most widely prevalent infectious diseases in the world. It affects more than half of the world's population. The current treatment for necrotic dental pulp tissue arising from dental caries is root canal therapy. This treatment results in loss of tooth sensitivity and vitality making it prone for secondary infections. Over the past decade, several tissue-engineering approaches have attempted regeneration of the dental pulp tissue. Although several studies have highlighted the potential of dental stem cells, none have transitioned into a clinical setting owing to limited availability of dental stem cells and the need for growth factor delivery systems. Our strategy is to utilize the intact ECM of pulp cells to drive lineage specific differentiation of bone marrow derived mesenchymal stem cells. From a clinical perspective, pulp ECM scaffolds can be generated using cell lines and patient specific somatic stem cells can be used for regeneration. Our published results have shown the feasibility of using pulp ECM scaffolds for odontogenic differentiation of non-dental mesenchymal cells. This focused review discusses the issues surrounding dental pulp tissue regeneration and the potential of our strategy to overcome these issues. PMID:25954205

  16. Development of biomaterial scaffold for nerve tissue engineering: Biomaterial mediated neural regeneration

    Directory of Open Access Journals (Sweden)

    Sethuraman Swaminathan

    2009-11-01

    Full Text Available Abstract Neural tissue repair and regeneration strategies have received a great deal of attention because it directly affects the quality of the patient's life. There are many scientific challenges to regenerate nerve while using conventional autologous nerve grafts and from the newly developed therapeutic strategies for the reconstruction of damaged nerves. Recent advancements in nerve regeneration have involved the application of tissue engineering principles and this has evolved a new perspective to neural therapy. The success of neural tissue engineering is mainly based on the regulation of cell behavior and tissue progression through the development of a synthetic scaffold that is analogous to the natural extracellular matrix and can support three-dimensional cell cultures. As the natural extracellular matrix provides an ideal environment for topographical, electrical and chemical cues to the adhesion and proliferation of neural cells, there exists a need to develop a synthetic scaffold that would be biocompatible, immunologically inert, conducting, biodegradable, and infection-resistant biomaterial to support neurite outgrowth. This review outlines the rationale for effective neural tissue engineering through the use of suitable biomaterials and scaffolding techniques for fabrication of a construct that would allow the neurons to adhere, proliferate and eventually form nerves.

  17. Development of biomaterial scaffold for nerve tissue engineering: Biomaterial mediated neural regeneration

    Science.gov (United States)

    2009-01-01

    Neural tissue repair and regeneration strategies have received a great deal of attention because it directly affects the quality of the patient's life. There are many scientific challenges to regenerate nerve while using conventional autologous nerve grafts and from the newly developed therapeutic strategies for the reconstruction of damaged nerves. Recent advancements in nerve regeneration have involved the application of tissue engineering principles and this has evolved a new perspective to neural therapy. The success of neural tissue engineering is mainly based on the regulation of cell behavior and tissue progression through the development of a synthetic scaffold that is analogous to the natural extracellular matrix and can support three-dimensional cell cultures. As the natural extracellular matrix provides an ideal environment for topographical, electrical and chemical cues to the adhesion and proliferation of neural cells, there exists a need to develop a synthetic scaffold that would be biocompatible, immunologically inert, conducting, biodegradable, and infection-resistant biomaterial to support neurite outgrowth. This review outlines the rationale for effective neural tissue engineering through the use of suitable biomaterials and scaffolding techniques for fabrication of a construct that would allow the neurons to adhere, proliferate and eventually form nerves. PMID:19939265

  18. mTOR signaling promotes stem cell activation via counterbalancing BMP-mediated suppression during hair regeneration.

    Science.gov (United States)

    Deng, Zhili; Lei, Xiaohua; Zhang, Xudong; Zhang, Huishan; Liu, Shuang; Chen, Qi; Hu, Huimin; Wang, Xinyue; Ning, Lina; Cao, Yujing; Zhao, Tongbiao; Zhou, Jiaxi; Chen, Ting; Duan, Enkui

    2015-02-01

    Hair follicles (HFs) undergo cycles of degeneration (catagen), rest (telogen), and regeneration (anagen) phases. Anagen begins when the hair follicle stem cells (HFSCs) obtain sufficient activation cues to overcome suppressive signals, mainly the BMP pathway, from their niche cells. Here, we unveil that mTOR complex 1 (mTORC1) signaling is activated in HFSCs, which coincides with the HFSC activation at the telogen-to-anagen transition. By using both an inducible conditional gene targeting strategy and a pharmacological inhibition method to ablate or inhibit mTOR signaling in adult skin epithelium before anagen initiation, we demonstrate that HFs that cannot respond to mTOR signaling display significantly delayed HFSC activation and extended telogen. Unexpectedly, BMP signaling activity is dramatically prolonged in mTOR signaling-deficient HFs. Through both gain- and loss-of-function studies in vitro, we show that mTORC1 signaling negatively affects BMP signaling, which serves as a main mechanism whereby mTORC1 signaling facilitates HFSC activation. Indeed, in vivo suppression of BMP by its antagonist Noggin rescues the HFSC activation defect in mTORC1-null skin. Our findings reveal a critical role for mTOR signaling in regulating stem cell activation through counterbalancing BMP-mediated repression during hair regeneration. © The Author (2015). Published by Oxford University Press on behalf of Journal of Molecular Cell Biology, IBCB, SIBS, CAS. All rights reserved.

  19. Optimization of in vitro regeneration and Agrobacterium tumefaciens-mediated transformation with heat-resistant cDNA in Brassica oleracea subsp. italica cv. Green Marvel.

    Science.gov (United States)

    Ravanfar, Seyed Ali; Aziz, Maheran Abdul; Saud, Halimi Mohd; Abdullah, Janna Ong

    2015-11-01

    An efficient system for shoot regeneration and Agrobacterium tumefaciens-mediated transformation of Brassica oleracea cv. Green Marvel cultivar is described. This study focuses on developing shoot regeneration from hypocotyl explants of broccoli cv. Green Marvel using thidiazuron (TDZ), zeatin, and kinetin, the optimization of factors affecting Agrobacterium-mediated transformation of the hypocotyl explants with heat-resistant cDNA, followed by the confirmation of transgenicity of the regenerants. High shoot regeneration was observed in 0.05-0.1 mg dm(-3) TDZ. TDZ at 0.1 mg dm(-3) produced among the highest percentage of shoot regeneration (96.67 %) and mean number of shoot formation (6.17). The highest percentage (13.33 %) and mean number (0.17) of putative transformant production were on hypocotyl explants subjected to preculture on shoot regeneration medium (SRM) with 200 µM acetosyringone. On optimization of bacterial density and inoculation time, the highest percentage and mean number of putative transformant production were on hypocotyl explants inoculated with a bacterial dilution of 1:5 for 30 min. Polymerase chain reaction (PCR) assay indicated a transformation efficiency of 8.33 %. The luciferase assay showed stable integration of the Arabidopsis thaliana HSP101 (AtHSP101) cDNA in the transgenic broccoli regenerants. Three out of five transgenic lines confirmed through PCR showed positive hybridization bands of the AtHSP101 cDNA through Southern blot analysis. The presence of AtHSP101 transcripts in the three transgenic broccoli lines indicated by reverse transcription-PCR (RT-PCR) confirmed the expression of the gene. In conclusion, an improved regeneration system has been established from hypocotyl explants of broccoli followed by successful transformation with AtHSP101 for resistance to high temperature.

  20. Transection of the hepatic parenchyma associated or not with the contralateral portal vein branch ligature and its effect in liver regeneration.

    Science.gov (United States)

    Wiederkehr, Henrique de Aguiar; Wiederkehr, Julio Cesar; Collaço, Luiz Martins; Sousa, Eros Luiz de; Salvalaggio, Paolo; Carvalho, Caroline Aragão de; Wiederkehr, Barbara de Aguiar; Marques, Camila Aparecida Moraes; Rosa, Francielle França da; Nanni, Felipe de Negreiros; Fuchs, Taíse

    2017-01-01

    To analyze the influence of portal vein ligation in hepatic regeneration by immunohistochemical criteria. Ten pigs divided into two groups of five animals underwent hepatectomy in two stages, and the groups were differentiated by ligation or not of the left portal vein tributary, which is responsible for vascularization of the left lateral and medial lobes of the pig liver. Five days after the procedure, the animals underwent liver biopsies for further analysis of histological and immunohistochemical with marker Ki67. The group submitted to hepatectomy with vascular ligation showed an increase of approximately 4% of hepatocytes in regeneration status, as well as a greater presence of Kupffer and inflammatory cells as compared to control. As a result of positive cell replication observed through the Ki67 marker, we can suspect that the ligation of a tributary of the portal vein associated with liver resection promoted a greater stimulus of liver regeneration when compared to liver resection alone. Analisar a influência da ligadura da tributária da veia porta no estímulo regenerativo hepático por meio de critérios imuno-histoquímicos. Dez suínos, divididos em dois grupos de cinco animais, foram submetidos à hepatectomia em dois estágios, sendo que os grupos foram diferenciados pela ligadura ou não da tributária da veia porta, responsável pela vascularização dos lobos lateral e medial esquerdos do fígado do suíno. Cinco dias após o procedimento, os animais foram reabordados para retirada de amostras hepáticas para posterior análise de histológica e imunoistoquímica com o marcador Ki67. O grupo submetido à hepatectomia com ligadura vascular apresentou incremento de 4% aproximadamente de hepatócitos em processo de regeneração, bem como grande número de células de Kupffer e células inflamatórias, quando comparado ao controle. Em virtude da análise positiva da replicação celular observada por meio do marcador Ki67, pode-se observar que a

  1. Mechanisms mediating the trophic effect of nerves during vertebrate limb regeneration

    International Nuclear Information System (INIS)

    Munaim, S.I.

    1986-01-01

    Salamanders regenerate their appendages after amputation and nerves are required for this process. Experiments were designed to test the idea that one way nerves could affect blastema cell proliferation is by influencing the metabolism of extracellular matrix (ECM) components and to identify neurotrophic factors which promote blastema cell mitosis. Temporal and spatial differences of glycosaminoglycans (GAGs) synthesis is innervated and denervated limbs were examined. Hyaluronic acid (HA) was found to be the major GAG produced during the proliferative period and chondroitin sulfate during differentiation. Denervation reduced synthesis of both these components by half. Dorsal root ganglia and fibroblast growth factor (FGF), a brain-derived mitogen, similarly doubled GAG synthesis in cultured blastemas, the FGF-effect being primarily on HA production. Histochemical and autoradiographical results confirmed the biochemical data. Autoradiography of the limb tissue showed heaviest labeling of the ECM with 3 H-acetate in areas which also stained most intensely with the dye, carbocyanine DBTC. Denervation reduced the staining and the radioactive labeling. These data indicate that nerves affect synthesis and accumulation of GAGs in the regenerating limb, which may be one way blastema cell proliferation is promoted

  2. Methylation of Septin9 mediated by DNMT3a enhances hepatic stellate cells activation and liver fibrogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Yuting, E-mail: wuyuting1302@sina.com; Bu, Fangtian; Yu, Haixia; Li, Wanxia; Huang, Cheng; Meng, Xiaoming; Zhang, Lei; Ma, Taotao; Li, Jun, E-mail: lj@ahmu.edu.cn

    2017-01-15

    Liver fibrosis, resulting from chronic and persistent injury to the liver, is a worldwide health problem. Advanced liver fibrosis results in cirrhosis, liver failure and even hepatocellular cancer (HCC), often eventually requiring liver transplantation, poses a huge health burden on the global community. However, the specific pathogenesis of liver fibrosis remains not fully understood. Numerous basic and clinical studies have provided evidence that epigenetic modifications, especially DNA methylation, might contribute to the activation of hepatic stellate cells (HSCs), the pivotal cell type responsible for the fibrous scar in liver. Here, reduced representation bisulfite sequencing (RRBS) and bisulfite pyrosequencing PCR (BSP) analysis identified hypermethylation status of Septin9 (Sept9) gene in liver fibrogenesis. Sept9 protein was dramatically decreased in livers of CCl4-treated mice and immortalized HSC-T6 cells exposed to TGF-β1. Nevertheless, the suppression of Sept9 could be blocked by DNMT3a-siRNA and DNA methyltransferase inhibitor, 5-aza-2′-deoxycytidine (5-azadC). Overexpressed Sept9 attenuated TGF-β1-induced expression of myofibroblast markers α-SMA and Col1a1, accompanied by up-regulation of cell apoptosis-related proteins. Conversely, RNAi-mediated silencing of Sept9 enhanced accumulation of extracellular matrix. These observations suggested that Sept9 contributed to alleviate liver fibrosis might partially through promoting activated HSCs apoptosis and this anti-fibrogenesis effect might be blocked by DNMT-3a mediated methylation of Sept9. Therefore, pharmacological agents that inhibit Sept9 methylation and increase its expression could be considered as valuable treatments for liver fibrosis. - Highlights: • This is the first report of Sept9 methylation and function in liver fibrosis. • Ectopic expression of Sept9 could block the liver fibrogenesis. • DNMT3a might be responsible for the suppression of Sept9 in liver fibrosis.

  3. Methylation of Septin9 mediated by DNMT3a enhances hepatic stellate cells activation and liver fibrogenesis

    International Nuclear Information System (INIS)

    Wu, Yuting; Bu, Fangtian; Yu, Haixia; Li, Wanxia; Huang, Cheng; Meng, Xiaoming; Zhang, Lei; Ma, Taotao; Li, Jun

    2017-01-01

    Liver fibrosis, resulting from chronic and persistent injury to the liver, is a worldwide health problem. Advanced liver fibrosis results in cirrhosis, liver failure and even hepatocellular cancer (HCC), often eventually requiring liver transplantation, poses a huge health burden on the global community. However, the specific pathogenesis of liver fibrosis remains not fully understood. Numerous basic and clinical studies have provided evidence that epigenetic modifications, especially DNA methylation, might contribute to the activation of hepatic stellate cells (HSCs), the pivotal cell type responsible for the fibrous scar in liver. Here, reduced representation bisulfite sequencing (RRBS) and bisulfite pyrosequencing PCR (BSP) analysis identified hypermethylation status of Septin9 (Sept9) gene in liver fibrogenesis. Sept9 protein was dramatically decreased in livers of CCl4-treated mice and immortalized HSC-T6 cells exposed to TGF-β1. Nevertheless, the suppression of Sept9 could be blocked by DNMT3a-siRNA and DNA methyltransferase inhibitor, 5-aza-2′-deoxycytidine (5-azadC). Overexpressed Sept9 attenuated TGF-β1-induced expression of myofibroblast markers α-SMA and Col1a1, accompanied by up-regulation of cell apoptosis-related proteins. Conversely, RNAi-mediated silencing of Sept9 enhanced accumulation of extracellular matrix. These observations suggested that Sept9 contributed to alleviate liver fibrosis might partially through promoting activated HSCs apoptosis and this anti-fibrogenesis effect might be blocked by DNMT-3a mediated methylation of Sept9. Therefore, pharmacological agents that inhibit Sept9 methylation and increase its expression could be considered as valuable treatments for liver fibrosis. - Highlights: • This is the first report of Sept9 methylation and function in liver fibrosis. • Ectopic expression of Sept9 could block the liver fibrogenesis. • DNMT3a might be responsible for the suppression of Sept9 in liver fibrosis.

  4. A Switch in the Dynamics of Intra-Platelet VEGF-A from Cancer to the Later Phase of Liver Regeneration after Partial Hepatectomy in Humans.

    Directory of Open Access Journals (Sweden)

    Bibek Aryal

    Full Text Available Liver regeneration (LR involves an early inductive phase characterized by the proliferation of hepatocytes, and a delayed angiogenic phase distinguished by the expansion of non-parenchymal compartment. The interest in understanding the mechanism of LR has lately shifted from the proliferation and growth of parenchymal cells to vascular remodeling during LR. Angiogenesis accompanied by LR exerts a pivotal role to accomplish the process. Vascular endothelial growth factor (VEGF has been elucidated as the most dynamic regulator of angiogenesis. From this perspective, platelet derived/Intra-platelet (IP VEGF-A should be associated with LR.Thirty-seven patients diagnosed with hepatocellular carcinoma and undergoing partial hepatectomy (PH were enrolled in the study. Serum and IP VEGF-A was monitored preoperatively and at four weeks of PH. Liver volumetry was determined on computer models derived from computed tomography (CT scan.Serum and IP VEGF-A was significantly elevated at four weeks of PH. Preoperative IP VEGF-A was higher in patients with advanced cancer and vascular invasion. Postoperative IP VEGF-A was higher after major liver resection. There was a statistically significant correlation between postoperative IP VEGF-A and the future remnant liver volume. Moreover, the soluble vascular endothelial growth factor receptor-1 (sVEGFR1 was distinctly down-regulated suggesting a fine-tuned angiogenesis at the later phase of LR.IP VEGF-A is overexpressed during later phase of LR suggesting its implications in inducing angiogenesis during LR.

  5. Comparative Study of Compensatory Liver Regeneration in a Rat Model: Portal Vein Ligation Only versus Sequential Ligation of the Portal Vein and Hepatic Artery

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Soo Young [Dept. of Pathology, Dongnam Institute of Radiological and Medical Sciences, Busan (Korea, Republic of); Jeon, Gyeong Sik [Dept. of Radiology, CHA Bundang Medical Center, College of Medicine, CHA University, Seongnam (Korea, Republic of); Lee, Byung Mo [Dept. of Surgery, Seoul Paik Hospital, Inje University College of Medicine, Seoul (Korea, Republic of)

    2013-04-15

    To compare the volume change and the regenerative capacity between portal vein ligation (embolization) (PVL) and heterochronous PVL with hepatic artery ligation (HAL) in a rodent model. The animals were separated into three groups: group I, ligation of the left lateral and median portal vein branches; group II, completion of PVL, followed by ligation of the same branches of the hepatic artery after 48 h; control group, laparotomy without ligation was performed. Five rats from each group were sacrificed on 1, 3, 5, and 7 days after the operation. Volume change measurement, liver function tests and immunohistochemical analysis were performed. The volume of the nonligated lobe between groups I and II was not significantly different by day 5 and day 7. Mean alanine aminotransferase and total bilirubin levels were significantly higher in group II, while the albumin level was higher in group I. Both c-kit- and MIB-5-positive cells used in the activity detection of regeneration were more prevalent in group I on day 1, 3, and 5, with statistical significance. There was no operation related mortality. PVL alone is safe and effective in compensatory liver regeneration. Performing both PVL and HAL does not confer any additional benefits.

  6. The value of the indirect immunoradiometric assay of serum alpha - fetoprotein in detecting liver regeneration and neoplastic transformation in chronic liver disease. Part of a coordinated programme on in vitro assay techniques

    International Nuclear Information System (INIS)

    Voiculetz, N.

    1979-07-01

    To investigate the concentration of alphafetoprotein AFP in different liver diseases and above all in liver cancer the immunoradiometric assay was utilized. The results of AFP studies were compared with regeneration index, blastic T lymphocytes transformation as well as other morphological and biochemical data. The results of the investigations indicated that: 38% of chronic benign hepatopathies displayed the values of serum AFP in normal ranges, 54% were in the range of 41 - 200ng/ml, and 8% showed 200 and more ng/ml. The most important conclusion from the work performed was that the elevation of serum AFP level in the evaluation of chronic hepatopathies, especially in cirrhoses, appears as an index of malignancy

  7. Acute liver allograft antibody-mediated rejection: an inter-institutional study of significant histopathological features.

    Science.gov (United States)

    O'Leary, Jacqueline G; Michelle Shiller, S; Bellamy, Christopher; Nalesnik, Michael A; Kaneku, Hugo; Jennings, Linda W; Isse, Kumiko; Terasaki, Paul I; Klintmalm, Göran B; Demetris, Anthony J

    2014-10-01

    Acute antibody-mediated rejection (AMR) occurs in a small minority of sensitized liver transplant recipients. Although histopathological characteristics have been described, specific features that could be used (1) to make a generalizable scoring system and (2) to trigger a more in-depth analysis are needed to screen for this rare but important finding. Toward this goal, we created training and validation cohorts of putative acute AMR and control cases from 3 high-volume liver transplant programs; these cases were evaluated blindly by 4 independent transplant pathologists. Evaluations of hematoxylin and eosin (H&E) sections were performed alone without knowledge of either serum donor-specific human leukocyte antigen alloantibody (DSA) results or complement component 4d (C4d) stains. Routine histopathological features that strongly correlated with severe acute AMR included portal eosinophilia, portal vein endothelial cell hypertrophy, eosinophilic central venulitis, central venulitis severity, and cholestasis. Acute AMR inversely correlated with lymphocytic venulitis and lymphocytic portal inflammation. These and other characteristics were incorporated into models created from the training cohort alone. The final acute antibody-mediated rejection score (aAMR score)--the sum of portal vein endothelial cell hypertrophy, portal eosinophilia, and eosinophilic venulitis divided by the sum of lymphocytic portal inflammation and lymphocytic venulitis--exhibited a strong correlation with severe acute AMR in the training cohort [odds ratio (OR) = 2.86, P  1.75 (sensitivity = 34%, specificity = 86%) and another that optimized sensitivity at a score > 1.0 (sensitivity = 81%, specificity = 71%). In conclusion, the routine histopathological features of the aAMR score can be used to screen patients for acute AMR via routine H&E staining of indication liver transplant biopsy samples; however, a definitive diagnosis requires substantiation by DSA testing

  8. Agrobacterium-mediated genetic transformation and plant regeneration of the hardwood tree species Fraxinus profunda

    Science.gov (United States)

    Micah E. Stevens; Paula M. Pijut

    2014-01-01

    Using mature hypocotyls as the initial explants, an Agrobacterium tumefaciens-mediated genetic transformation system was successfully developed for pumpkin ash (Fraxinus profunda). This transformation protocol is an invaluable tool to combat the highly aggressive, non-native emerald ash borer (EAB), which has the potential to...

  9. Concomitant apoptosis and regeneration of liver cells as a mechanism of liver-tumor promotion by β-naphthoflavone involving TNFα-signaling due to oxidative cellular stress in rats

    International Nuclear Information System (INIS)

    Kuwata, Kazunori; Shibutani, Makoto; Hayashi, Hitomi; Shimamoto, Keisuke; Hayashi, Shim-Mo; Suzuki, Kazuhiko; Mitsumori, Kunitoshi

    2011-01-01

    β-Naphthoflavone (BNF) is a strong inducer of cytochrome P450 1A enzymes, and exerts liver tumor-promoting activity through enhancement of oxidative stress responses in rats. This study investigated the role of the tissue environment surrounding hepatocellular preneoplastic lesions in the early tumor-promotion stage by BNF, using enzymatically modified isoquercitrin (EMIQ) as an anti-oxidative chemopreventive agent. Male F344 rats were fed a diet containing BNF (0.5%) for 6 weeks, with or without EMIQ (0.2%) in the drinking water, 2 weeks after initiation with N-diethylnitrosamine, and were subjected to two-thirds partial hepatectomy 1 week after starting BNF-promotion. BNF-treatment increased concentrations of liver thiobarbituric acid-reactive substances, single liver cells expressing glutathione S-transferase placental form or heme oxygenase (HO)-1, and concomitant apoptosis and proliferation of liver cells. Transcript upregulation of anti-oxidative enzymes (Aldh1a1 and Nqo1), cell cycle-related molecules (Cdc20 and Cdkn2b) and inflammation-related molecules including proinflammatory cytokines (Ccl2, Col1a1, Il6, Nos2 and Serpine1) was also evident. Furthermore, BNF increased HO-1-expressing Kupffer cells and liver cells expressing tumor necrosis factor receptor 1 (TNFR1) and the TNFR1-associated death domain. Most of these BNF-induced fluctuations disappeared or were suppressed by EMIQ in conjunction with suppression of tumor-promotion. Tnf transcript levels with BNF were also suppressed by EMIQ. These results suggest that BNF-induced oxidative stress causes single liver cell toxicity, allowing subsequent concomitant apoptosis and regeneration involving inflammatory responses including TNFα-signaling, contributing to tumor promotion. Kupffer cells may act to protect against inflammatory stimuli induced as a result of oxidative cellular stress by BNF, causing proinflammatory cytokine level fluctuations.

  10. Adult Lung Spheroid Cells Contain Progenitor Cells and Mediate Regeneration in Rodents With Bleomycin-Induced Pulmonary Fibrosis.

    Science.gov (United States)

    Henry, Eric; Cores, Jhon; Hensley, M Taylor; Anthony, Shirena; Vandergriff, Adam; de Andrade, James B M; Allen, Tyler; Caranasos, Thomas G; Lobo, Leonard J; Cheng, Ke

    2015-11-01

    Lung diseases are devastating conditions and ranked as one of the top five causes of mortality worldwide according to the World Health Organization. Stem cell therapy is a promising strategy for lung regeneration. Previous animal and clinical studies have focused on the use of mesenchymal stem cells (from other parts of the body) for lung regenerative therapies. We report a rapid and robust method to generate therapeutic resident lung progenitors from adult lung tissues. Outgrowth cells from healthy lung tissue explants are self-aggregated into three-dimensional lung spheroids in a suspension culture. Without antigenic sorting, the lung spheroids recapitulate the stem cell niche and contain a natural mixture of lung stem cells and supporting cells. In vitro, lung spheroid cells can be expanded to a large quantity and can form alveoli-like structures and acquire mature lung epithelial phenotypes. In severe combined immunodeficiency mice with bleomycin-induced pulmonary fibrosis, intravenous injection of human lung spheroid cells inhibited apoptosis, fibrosis, and infiltration but promoted angiogenesis. In a syngeneic rat model of pulmonary fibrosis, lung spheroid cells outperformed adipose-derived mesenchymal stem cells in reducing fibrotic thickening and infiltration. Previously, lung spheroid cells (the spheroid model) had only been used to study lung cancer cells. Our data suggest that lung spheroids and lung spheroid cells from healthy lung tissues are excellent sources of regenerative lung cells for therapeutic lung regeneration. The results from the present study will lead to future human clinical trials using lung stem cell therapies to treat various incurable lung diseases, including pulmonary fibrosis. The data presented here also provide fundamental knowledge regarding how injected stem cells mediate lung repair in pulmonary fibrosis. ©AlphaMed Press.

  11. Features of the postirradiation regeneration of liver mitochondria of gamma-irradiated mice treated with the Testudo horsfieldi spleen extract

    Energy Technology Data Exchange (ETDEWEB)

    Turdyev, A.A.; Ivanov, V.I.; Trifonov, Yu.A.; Abbasova, I.A.; Usmanov, R.B.

    A study was made of the effect of a drug prepared from a spleen extract of Testudo horsfieldi on energy metabolism and lipid composition of liver mitochondria of irradiated mice (2.06 x 10/sup -1/ C/kg). It was shown that the decompensated low-energy state of liver mitochondria of the exposed mice was changed into the state of the compensated low-energy shift: the physicochemical properties of lipid microenvironment of mitochondria proteins were partially restored.

  12. Resveratrol Promotes Nerve Regeneration via Activation of p300 Acetyltransferase-Mediated VEGF Signaling in a Rat Model of Sciatic Nerve Crush Injury.

    Science.gov (United States)

    Ding, Zhuofeng; Cao, Jiawei; Shen, Yu; Zou, Yu; Yang, Xin; Zhou, Wen; Guo, Qulian; Huang, Changsheng

    2018-01-01

    Peripheral nerve injuries are generally associated with incomplete restoration of motor function. The slow rate of nerve regeneration after injury may account for this. Although many benefits of resveratrol have been shown in the nervous system, it is not clear whether resveratrol could promote fast nerve regeneration and motor repair after peripheral nerve injury. This study showed that the motor deficits caused by sciatic nerve crush injury were alleviated by daily systematic resveratrol treatment within 10 days. Resveratrol increased the number of axons in the distal part of the injured nerve, indicating enhanced nerve regeneration. In the affected ventral spinal cord, resveratrol enhanced the expression of several vascular endothelial growth factor family proteins (VEGFs) and increased the phosphorylation of p300 through Akt signaling, indicating activation of p300 acetyltransferase. Inactivation of p300 acetyltransferase reversed the resveratrol-induced expression of VEGFs and motor repair in rats that had undergone sciatic nerve crush injury. The above results indicated that daily systematic resveratrol treatment promoted nerve regeneration and led to rapid motor repair. Resveratrol activated p300 acetyltransferase-mediated VEGF signaling in the affected ventral spinal cord, which may have thus contributed to the acceleration of nerve regeneration and motor repair.

  13. Site-Specific Bioconjugation of an Organometallic Electron Mediator to an Enzyme with Retained Photocatalytic Cofactor Regenerating Capacity and Enzymatic Activity

    Directory of Open Access Journals (Sweden)

    Sung In Lim

    2015-04-01

    Full Text Available Photosynthesis consists of a series of reactions catalyzed by redox enzymes to synthesize carbohydrates using solar energy. In order to take the advantage of solar energy, many researchers have investigated artificial photosynthesis systems mimicking the natural photosynthetic enzymatic redox reactions. These redox reactions usually require cofactors, which due to their high cost become a key issue when constructing an artificial photosynthesis system. Combining a photosensitizer and an Rh-based electron mediator (RhM has been shown to photocatalytically regenerate cofactors. However, maintaining the high concentration of cofactors available for efficient enzymatic reactions requires a high concentration of the expensive RhM; making this process cost prohibitive. We hypothesized that conjugation of an electron mediator to a redox enzyme will reduce the amount of electron mediators necessary for efficient enzymatic reactions. This is due to photocatalytically regenerated NAD(PH being readily available to a redox enzyme, when the local NAD(PH concentration near the enzyme becomes higher. However, conventional random conjugation of RhM to a redox enzyme will likely lead to a substantial loss of cofactor regenerating capacity and enzymatic activity. In order to avoid this issue, we investigated whether bioconjugation of RhM to a permissive site of a redox enzyme retains cofactor regenerating capacity and enzymatic activity. As a model system, a RhM was conjugated to a redox enzyme, formate dehydrogenase obtained from Thiobacillus sp. KNK65MA (TsFDH. A RhM-containing azide group was site-specifically conjugated to p-azidophenylalanine introduced to a permissive site of TsFDH via a bioorthogonal strain-promoted azide-alkyne cycloaddition and an appropriate linker. The TsFDH-RhM conjugate exhibited retained cofactor regenerating capacity and enzymatic activity.

  14. Carbamazepine suppresses calpain-mediated autophagy impairment after ischemia/reperfusion in mouse livers

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae-Sung, E-mail: Jae.Kim@surgery.ufl.edu; Wang, Jin-Hee, E-mail: jin-hee.wang@surgery.ufl.edu; Biel, Thomas G., E-mail: Thomas.Biel@surgery.ufl.edu; Kim, Do-Sung, E-mail: do-sung.kim@surgery.med.ufl.edu; Flores-Toro, Joseph A., E-mail: Joseph.Flores-Toro@surgery.ufl.edu; Vijayvargiya, Richa, E-mail: rvijayvargiya@ufl.edu; Zendejas, Ivan, E-mail: ivan.zendejas@surgery.ufl.edu; Behrns, Kevin E., E-mail: Kevin.Behrns@surgery.ufl.edu

    2013-12-15

    Onset of the mitochondrial permeability transition (MPT) plays a causative role in ischemia/reperfusion (I/R) injury. Current therapeutic strategies for reducing reperfusion injury remain disappointing. Autophagy is a lysosome-mediated, catabolic process that timely eliminates abnormal or damaged cellular constituents and organelles such as dysfunctional mitochondria. I/R induces calcium overloading and calpain activation, leading to degradation of key autophagy-related proteins (Atg). Carbamazepine (CBZ), an FDA-approved anticonvulsant drug, has recently been reported to increase autophagy. We investigated the effects of CBZ on hepatic I/R injury. Hepatocytes and livers from male C57BL/6 mice were subjected to simulated in vitro, as well as in vivo I/R, respectively. Cell death, intracellular calcium, calpain activity, changes in autophagy-related proteins (Atg), autophagic flux, MPT and mitochondrial membrane potential after I/R were analyzed in the presence and absence of 20 μM CBZ. CBZ significantly increased hepatocyte viability after reperfusion. Confocal microscopy revealed that CBZ prevented calcium overloading, the onset of the MPT and mitochondrial depolarization. Immunoblotting and fluorometric analysis showed that CBZ blocked calpain activation, depletion of Atg7 and Beclin-1 and loss of autophagic flux after reperfusion. Intravital multiphoton imaging of anesthetized mice demonstrated that CBZ substantially reversed autophagic defects and mitochondrial dysfunction after I/R in vivo. In conclusion, CBZ prevents calcium overloading and calpain activation, which, in turn, suppresses Atg7 and Beclin-1 depletion, defective autophagy, onset of the MPT and cell death after I/R. - Highlights: • A mechanism of carbamazepine (CBZ)-induced cytoprotection in livers is proposed. • Impaired autophagy is a key event contributing to lethal reperfusion injury. • The importance of autophagy is extended and confirmed in an in vivo model. • CBZ is a potential

  15. Vismodegib suppresses TRAIL-mediated liver injury in a mouse model of nonalcoholic steatohepatitis.

    Directory of Open Access Journals (Sweden)

    Petra Hirsova

    Full Text Available Hedgehog signaling pathway activation has been implicated in the pathogenesis of NASH. Despite this concept, hedgehog pathway inhibitors have not been explored. Thus, we examined the effect of vismodegib, a hedgehog signaling pathway inhibitor, in a diet-induced model of NASH. C57BL/6 mice were placed on 3-month chow or FFC (high saturated fats, fructose, and cholesterol diet. One week prior to sacrifice, mice were treated with vismodegib or vehicle. Mice fed the FFC diet developed significant steatosis, which was unchanged by vismodegib therapy. In contrast, vismodegib significantly attenuated FFC-induced liver injury as manifested by reduced serum ALT and hepatic TUNEL-positive cells. In line with the decreased apoptosis, vismodegib prevented FFC-induced strong upregulation of death receptor DR5 and its ligand TRAIL. In addition, FFC-fed mice, but not chow-fed animals, underwent significant liver injury and apoptosis following treatment with a DR5 agonist; however, this injury was prevented by pre-treatment with vismodegib. Consistent with a reduction in liver injury, vismodegib normalized FFC-induced markers of inflammation including mRNA for TNF-α, IL-1β, IL-6, monocyte chemotactic protein-1 and a variety of macrophage markers. Furthermore, vismodegib in FFC-fed mice abrogated indices of hepatic fibrogenesis. In conclusion, inhibition of hedgehog signaling with vismodegib appears to reduce TRAIL-mediated liver injury in a nutrient excess model of NASH, thereby attenuating hepatic inflammation and fibrosis. We speculate that hedgehog signaling inhibition may be salutary in human NASH.

  16. Agrobacterium-mediated genetic transformation and regeneration of transgenic plants using leaf midribs as explants in ramie [Boehmeria nivea (L.) Gaud].

    Science.gov (United States)

    An, Xia; Wang, Bo; Liu, Lijun; Jiang, Hui; Chen, Jie; Ye, Shengtuo; Chen, Leiyu; Guo, Pingan; Huang, Xing; Peng, Dingxiang

    2014-05-01

    In this study, leaf midribs, the elite explants, were used for the first time to develop an efficient regeneration and transformation protocol for ramie [Boehmeria nivea (L.) Gaud.] via Agrobacterium-mediated genetic transformation. Sensitivity of leaf midribs regeneration to kanamycin was evaluated, which showed that 40 mg l(-1) was the optimal concentration needed to create the necessary selection pressure. Factors affecting the ramie transformation efficiency were evaluated, including leaf age, Agrobacterium concentration, length of infection time for the Agrobacterium solution, acetosyringone concentration in the co-cultivation medium, and the co-cultivation period. The midrib explants from 40-day-old in vitro shoots, an Agrobacterium concentration at OD600 of 0.6, 10-min immersion in the bacteria solution, an acetosyringone concentration of 50 mg l(-1) in the co-cultivation medium and a 3-day co-cultivation period produced the highest efficiencies of regeneration and transformation. In this study, the average transformation rate was 23.25%. Polymerase chain reactions using GUS and NPTII gene-specific primers, Southern blot and histochemical GUS staining analyses further confirmed that the transgene was integrated into the ramie genome and expressed in the transgenic ramie. The establishment of this system of Agrobacterium-mediated genetic transformation and regeneration of transgenic plants will be used not only to introduce genes of interest into the ramie genome for the purpose of trait improvement, but also as a common means of testing gene function by enhancing or inhibiting the expression of target genes.

  17. Acute liver allograft antibody-mediated rejection:an inter-institutional study of significant histopathological features

    OpenAIRE

    O'Leary, Jacqueline G; Shiller, S Michelle; Bellamy, Christopher; Nalesnik, Michael A; Kaneku, Hugo; Jennings, Linda W; Isse, Kumiko; Terasaki, Paul I; Klintmalm, Göran B; Demetris, Anthony J

    2014-01-01

    Acute antibody-mediated rejection (AMR) occurs in a small minority of sensitized liver transplant recipients. Although histopathologic characteristics have been described, specific features that could be used: a) for a generalizable scoring system; and b) to trigger a more in-depth analysis are needed to screen for this rare but important finding. Toward this goal, we created a training and validation cohort from 3 high volume liver transplant programs of putative acute AMR and control cases ...

  18. CAR-mediated repression of Foxo1 transcriptional activity regulates the cell cycle inhibitor p21 in mouse livers

    International Nuclear Information System (INIS)

    Kazantseva, Yuliya A.; Yarushkin, Andrei A.; Pustylnyak, Vladimir O.

    2014-01-01

    Highlights: • CAR activation decreased the level of Foxo1 in mouse livers. • CAR activation decreased the level of p21 in mouse livers. • CAR activation inhibited Foxo1 transcriptional activity in mouse livers. - Abstract: 1,4-Bis[2-(3,5-dichloropyridyloxy)]benzene (TCPOBOP), an agonist of constitutive androstane receptor (CAR), is a well-known strong primary chemical mitogen for the mouse liver. Despite extensive investigation of the role of CAR in the regulation of cell proliferation, our knowledge of the intricate mediating mechanism is incomplete. In this study, we demonstrated that long-term CAR activation by TCPOBOP increased liver-to-body weight ratio and decreased tumour suppressor Foxo1 expression and transcriptional activity, which were correlated with reduced expression of genes regulated by Foxo1, including the cell-cycle inhibitor Cdkn1a(p21), and upregulation of the cell-cycle regulator Cyclin D1. Moreover, we demonstrated the negative regulatory effect of TCPOBOP-activated CAR on the association of Foxo1 with the target Foxo1 itself and Cdkn1a(p21) promoters. Thus, we identified CAR-mediated repression of cell cycle inhibitor p21, as mediated by repression of FOXO1 expression and transcriptional activity. CAR-FOXO1 cross-talk may provide new opportunities for understanding liver diseases and developing more effective therapeutic approaches to better drug treatments

  19. Elevated phosphatase of regenerating liver 3 (PRL-3) promotes cytoskeleton reorganization, cell migration and invasion in endometrial stromal cells from endometrioma.

    Science.gov (United States)

    Zhan, Hong; Ma, Junyan; Ruan, Fei; Bedaiwy, Mohamed A; Peng, Bo; Wu, Ruijin; Lin, Jun

    2016-04-01

    Is phosphatase of regenerating liver-3 (PRL-3) associated with increased motility of endometriotic cells from endometrioma? Elevated PRL-3 promotes cytoskeleton reorganization, cell migration and invasion of endometrial stromal cells (ESCs) from endometrioma. Overexpression of PRL-3 is associated with cancer cell migration, invasion and metastatic phenotype. Primary human ESCs were isolated from eutopic endometrium of women without endometriosis (EuCo, n = 10), with histologically proven endometrioma (EuEM, n = 19) and from the cyst wall of ovarian endometriosis (OvEM, n = 26). The expression of PRL-3 in ESCs derived from EuCo, EuEM and OvEM at different phases of menstrual cycle were compared. The protein and mRNA levels of PRL-3 were examined by western blot and RT-qPCR, respectively. ESCs from OvEM were transfected with/without short hairpin RNA (shRNA) or small interfering RNA (siRNA). Additionally, a plasmid-mediated delivery system was used to achieve PRL-3 overexpression in ESCs from EuEM. The cellular distribution of F-actin and α-tubulin were examined by immunocytochemistry. Cell motility was evaluated by a transwell migration/invasion assay. The protein and mRNA levels of PRL-3 are significantly elevated in ESCs from OvEM compared with EuCo and EuEM. The expression of PRL-3 was not altered between proliferative phase and secretory phase in ESCs from all groups. Knockdown of PRL-3 significantly modified the distribution of F-actin and α-tubulin cytoskeleton, inhibited cell migration and invasion. Endogenous inhibition of PRL-3 attenuated the expression of Ras homolog gene family members A and C (RhoA, RhoC), Rho-associated coiled-coil-containing protein kinase 1 (ROCK1) and matrix metalloproteinase (MMP) 9, but not MMP2 in ESCs from OvEM. Additionally, overexpression of PRL-3 in ESCs from EuEM up-regulates cell migration and invasion, and increases the expression of RhoA, RhoC, ROCK1 and MMP9. Lack of in vivo animal studies is the major limitation of our

  20. Catheter-directed Intraportal Delivery of Endothelial Cell Therapy for Liver Regeneration: A Feasibility Study in a Large-Animal Model of Cirrhosis.

    Science.gov (United States)

    Lee, Kyungmouk Steve; Santagostino, Sara F; Li, David; Ramjit, Amit; Serrano, Kenneth; Ginsberg, Michael D; Ding, Bi-Sen; Rafii, Shahin; Madoff, David C

    2017-10-01

    Purpose To demonstrate the feasibility of imaging-guided catheter-directed delivery of endothelial cell therapy in a porcine model of cirrhosis for liver regeneration. Materials and Methods After approval from the institutional animal care and use committee, autologous liver endothelial cells were grown from core hepatic specimens from swine. Cirrhosis was induced in swine by means of transcatheter infusion of ethanol and iodized oil into the hepatic artery. Three weeks after induction of cirrhosis, the swine were randomly assigned to receive autologous cell therapy (endothelial cells, n = 4) or control treatment (phosphate-buffered saline, n = 4) by means of imaging-guided transhepatic intraportal catheterization. Fluorescence-activated cell sorting analysis was performed on biopsy samples 1 hour after therapy. Three weeks after intraportal delivery of endothelial cells, the swine were euthanized and the explanted liver underwent quantitative pathologic examination. Statistical analysis was performed with an unpaired t test by using unequal variance. Results Liver endothelial cells were successfully isolated, cultured, and expanded from eight 20-mm, 18-gauge hepatic core samples to 50 × 10 6 autologous cells per pig. Intraportal delivery of endothelial cell therapy or saline was technically successful in all eight swine, with no complications. Endothelial cells were present in the liver for a minimum of 1 hour after intraportal infusion. Swine treated with endothelial cell therapy showed mean levels of surrogate markers of hepatobiliary injury that were consistent with decreases in hepatic fibrosis and biliary ductal damage relative to the control animals, although statistical significance was not met in this pilot study: The mean percentage of positive pixels at Masson trichrome staining was 7.28% vs 5.57%, respectively (P = .20), the mean proliferation index with cytokeratin wide-spectrum was 2.55 vs 1.13 (P = .06), and the mean proliferation index with Ki67

  1. Liver

    International Nuclear Information System (INIS)

    Bernardino, M.E.; Sones, P.J. Jr.; Barton Price, R.; Berkman, W.A.

    1984-01-01

    Evaluation of the liver for focal lesions is extremely important because the liver is one of the most common sites for metastatic disease. Most patients with metastatic deposits to the liver have a survival rate of about 6 months. Thus, metastatic disease to the liver has an extremely grave prognosis. In the past patients with hepatic lesions had no therapeutic recourse. However, with recent aggressive surgical advances (such as partial hepatectomies) and hepatic artery embolization, survival of patients with hepatic metastases has increased. Thus it is important for noninvasive imaging not only to detect lesions early in their course, but also to give their true hepatic involvement and the extent of the neoplastic process elsewhere in the body. Recent advances in imaging have been rapidly changing over the past 5 years. These changes have been more rapid in computed tomography (CT) and ultrasound than in radionuclide imaging. Thus, the question addressed in this chapter is: What is the relationship of hepatic ultrasound to the other current diagnostic modalities in detecting metastatic liver disease and other focal liver lesions? Also, what is its possible future relationship to nuclear magnetic resonance?

  2. Bile duct regeneration and immune response by passenger lymphocytes signals biliary recovery versus complications after liver transplantation.

    Science.gov (United States)

    Junger, Henrik H; Schlitt, Hans J; Geissler, Edward K; Fichtner-Feigl, Stefan; Brunner, Stefan M

    2017-11-01

    This study aimed to elucidate the impact of epithelial regenerative responses and immune cell infiltration on biliary complications after liver transplantation. Bile duct (BD) damage after cold storage was quantified by a BD damage score and correlated with patient outcome in 41 patients. Bacterial infiltration was determined by fluorescence in situ hybridization (FISH). BD samples were analyzed by immunohistochemistry for E-cadherin, cytokeratin, CD56, CD14, CD4, CD8, and double-immunofluorescence for cytokine production and by messenger RNA (mRNA) microarray. Increased mRNA levels of adherens junctions (P Liver Transplantation 23 1422-1432 2017 AASLD. © 2017 by the American Association for the Study of Liver Diseases.

  3. Liver-Enriched Gene 1, a Glycosylated Secretory Protein, Binds to FGFR and Mediates an Anti-stress Pathway to Protect Liver Development in Zebrafish.

    Directory of Open Access Journals (Sweden)

    Minjie Hu

    2016-02-01

    Full Text Available Unlike mammals and birds, teleost fish undergo external embryogenesis, and therefore their embryos are constantly challenged by stresses from their living environment. These stresses, when becoming too harsh, will cause arrest of cell proliferation, abnormal cell death or senescence. Such organisms have to evolve a sophisticated anti-stress mechanism to protect the process of embryogenesis/organogenesis. However, very few signaling molecule(s mediating such activity have been identified. liver-enriched gene 1 (leg1 is an uncharacterized gene that encodes a novel secretory protein containing a single domain DUF781 (domain of unknown function 781 that is well conserved in vertebrates. In the zebrafish genome, there are two copies of leg1, namely leg1a and leg1b. leg1a and leg1b are closely linked on chromosome 20 and share high homology, but are differentially expressed. In this report, we generated two leg1a mutant alleles using the TALEN technique, then characterized liver development in the mutants. We show that a leg1a mutant exhibits a stress-dependent small liver phenotype that can be prevented by chemicals blocking the production of reactive oxygen species. Further studies reveal that Leg1a binds to FGFR3 and mediates a novel anti-stress pathway to protect liver development through enhancing Erk activity. More importantly, we show that the binding of Leg1a to FGFR relies on the glycosylation at the 70th asparagine (Asn(70 or N(70, and mutating the Asn(70 to Ala(70 compromised Leg1's function in liver development. Therefore, Leg1 plays a unique role in protecting liver development under different stress conditions by serving as a secreted signaling molecule/modulator.

  4. Death receptor and mitochondria-mediated hepatocyte apoptosis underlies liver dysfunction in rats exposed to organic pollutants from drinking water

    Science.gov (United States)

    Yang, Guanghong; Zhou, Zhiwei; Cen, Yanli; Gui, Xiaolin; Zeng, Qibing; Ao, Yunxia; Li, Qian; Wang, Shiran; Li, Jun; Zhang, Aihua

    2015-01-01

    Persistent organic pollutants in drinking water impose a substantial risk to the health of human beings, but the evidence for liver toxic effect and the underlying mechanism is scarce. This study aimed to examine the liver toxicity and elucidate the molecular mechanism of organic pollutants in drinking water in normal human liver cell line L02 cells and rats. The data showed that organic extraction from drinking water remarkably impaired rat liver function, evident from the increase in the serum level of alanine aminotransferase, aspartate aminotransferase, and cholinesterase, and decrease in the serum level of total protein and albumin. Organic extraction dose-dependently induced apoptotic cell death in rat liver and L02 cells. Administration of rats with organic extraction promoted death receptor signaling pathway through the increase in gene and protein expression level of Fas and FasL. Treatment of rats with organic extraction also induced mitochondria-mediated apoptosis via increasing the expression level of proapoptotic protein, Bax, but decreasing the expression level of antiapoptotic protein, Bcl-2, resulting in an upregulation of cytochrome c and activation of caspase cascade at both transcriptional and post-transcriptional levels. Moreover, organic extraction enhanced rat liver glutathione S-transferases activity and reactive oxygen species generation, and upregulated aryl hydrocarbon receptor and glutathione S-transferase A1 at both transcriptional and translational levels. Collectively, the results indicate that organic extraction from drinking water impairs liver function, with the involvement of death receptor and mitochondria-mediated apoptosis in rats. The results provide evidence and molecular mechanisms for organic pollutants in drinking water-induced liver dysfunction, which may help prevent and treat organic extraction-induced liver injury. PMID:26316710

  5. Death receptor and mitochondria-mediated hepatocyte apoptosis underlies liver dysfunction in rats exposed to organic pollutants from drinking water.

    Science.gov (United States)

    Yang, Guanghong; Zhou, Zhiwei; Cen, Yanli; Gui, Xiaolin; Zeng, Qibing; Ao, Yunxia; Li, Qian; Wang, Shiran; Li, Jun; Zhang, Aihua

    2015-01-01

    Persistent organic pollutants in drinking water impose a substantial risk to the health of human beings, but the evidence for liver toxic effect and the underlying mechanism is scarce. This study aimed to examine the liver toxicity and elucidate the molecular mechanism of organic pollutants in drinking water in normal human liver cell line L02 cells and rats. The data showed that organic extraction from drinking water remarkably impaired rat liver function, evident from the increase in the serum level of alanine aminotransferase, aspartate aminotransferase, and cholinesterase, and decrease in the serum level of total protein and albumin. Organic extraction dose-dependently induced apoptotic cell death in rat liver and L02 cells. Administration of rats with organic extraction promoted death receptor signaling pathway through the increase in gene and protein expression level of Fas and FasL. Treatment of rats with organic extraction also induced mitochondria-mediated apoptosis via increasing the expression level of proapoptotic protein, Bax, but decreasing the expression level of antiapoptotic protein, Bcl-2, resulting in an upregulation of cytochrome c and activation of caspase cascade at both transcriptional and post-transcriptional levels. Moreover, organic extraction enhanced rat liver glutathione S-transferases activity and reactive oxygen species generation, and upregulated aryl hydrocarbon receptor and glutathione S-transferase A1 at both transcriptional and translational levels. Collectively, the results indicate that organic extraction from drinking water impairs liver function, with the involvement of death receptor and mitochondria-mediated apoptosis in rats. The results provide evidence and molecular mechanisms for organic pollutants in drinking water-induced liver dysfunction, which may help prevent and treat organic extraction-induced liver injury.

  6. Dysregulation of protein degradation pathways may mediate the liver injury and phospholipidosis associated with a cationic amphiphilic antibiotic drug

    International Nuclear Information System (INIS)

    Mosedale, Merrie; Wu, Hong; Kurtz, C. Lisa; Schmidt, Stephen P.; Adkins, Karissa; Harrill, Alison H.

    2014-01-01

    A large number of antibiotics are known to cause drug-induced liver injury in the clinic; however, interpreting clinical risk is not straightforward owing to a lack of predictivity of the toxicity by standard preclinical species and a poor understanding of the mechanisms of toxicity. An example is PF-04287881, a novel ketolide antibiotic that caused elevations in liver function tests in Phase I clinical studies. In this study, a mouse diversity panel (MDP), comprised of 34 genetically diverse, inbred mouse strains, was utilized to model the toxicity observed with PF-04287881 treatment and investigate potential mechanisms that may mediate the liver response. Significant elevations in serum alanine aminotransferase (ALT) levels in PF-04287881-treated animals relative to vehicle-treated controls were observed in the majority (88%) of strains tested following a seven day exposure. The average fold elevation in ALT varied by genetic background and correlated with microscopic findings of hepatocellular hypertrophy, hepatocellular single cell necrosis, and Kupffer cell vacuolation (confirmed as phospholipidosis) in the liver. Global liver mRNA expression was evaluated in a subset of four strains to identify transcript and pathway differences that distinguish susceptible mice from resistant mice in the context of PF-04287881 treatment. The protein ubiquitination pathway was highly enriched among genes associated with PF-04287881-induced hepatocellular necrosis. Expression changes associated with PF-04287881-induced phospholipidosis included genes involved in drug transport, phospholipid metabolism, and lysosomal function. The findings suggest that perturbations in genes involved in protein degradation leading to accumulation of oxidized proteins may mediate the liver injury induced by this drug. - Highlights: • Identified susceptible and resistant mouse strains to liver injury induced by a CAD • Liver injury characterized by single cell necrosis, and phospholipidosis

  7. Dysregulation of protein degradation pathways may mediate the liver injury and phospholipidosis associated with a cationic amphiphilic antibiotic drug

    Energy Technology Data Exchange (ETDEWEB)

    Mosedale, Merrie [Hamner-University of North Carolina Institute for Drug Safety Sciences, The Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709 (United States); Wu, Hong [Drug Safety Research and Development, Pfizer Global Research and Development, Groton, CT06340 (United States); Kurtz, C. Lisa [Hamner-University of North Carolina Institute for Drug Safety Sciences, The Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709 (United States); Schmidt, Stephen P. [Drug Safety Research and Development, Pfizer Global Research and Development, Groton, CT06340 (United States); Adkins, Karissa, E-mail: Karissa.Adkins@pfizer.com [Drug Safety Research and Development, Pfizer Global Research and Development, Groton, CT06340 (United States); Harrill, Alison H. [Hamner-University of North Carolina Institute for Drug Safety Sciences, The Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709 (United States); University of Arkansas for Medical Sciences, Little Rock, AR72205 (United States)

    2014-10-01

    A large number of antibiotics are known to cause drug-induced liver injury in the clinic; however, interpreting clinical risk is not straightforward owing to a lack of predictivity of the toxicity by standard preclinical species and a poor understanding of the mechanisms of toxicity. An example is PF-04287881, a novel ketolide antibiotic that caused elevations in liver function tests in Phase I clinical studies. In this study, a mouse diversity panel (MDP), comprised of 34 genetically diverse, inbred mouse strains, was utilized to model the toxicity observed with PF-04287881 treatment and investigate potential mechanisms that may mediate the liver response. Significant elevations in serum alanine aminotransferase (ALT) levels in PF-04287881-treated animals relative to vehicle-treated controls were observed in the majority (88%) of strains tested following a seven day exposure. The average fold elevation in ALT varied by genetic background and correlated with microscopic findings of hepatocellular hypertrophy, hepatocellular single cell necrosis, and Kupffer cell vacuolation (confirmed as phospholipidosis) in the liver. Global liver mRNA expression was evaluated in a subset of four strains to identify transcript and pathway differences that distinguish susceptible mice from resistant mice in the context of PF-04287881 treatment. The protein ubiquitination pathway was highly enriched among genes associated with PF-04287881-induced hepatocellular necrosis. Expression changes associated with PF-04287881-induced phospholipidosis included genes involved in drug transport, phospholipid metabolism, and lysosomal function. The findings suggest that perturbations in genes involved in protein degradation leading to accumulation of oxidized proteins may mediate the liver injury induced by this drug. - Highlights: • Identified susceptible and resistant mouse strains to liver injury induced by a CAD • Liver injury characterized by single cell necrosis, and phospholipidosis

  8. Free radical-mediated stimulation of tyrosine-specific protein kinase in rat liver plasma membrane

    International Nuclear Information System (INIS)

    Chan, T.M.; Tatoyan, A.; Cheng, E.; Shargill, N.S.; Pleta, M.

    1986-01-01

    Incorporation of 32 P from (γ- 32 P)-ATP into endogenous proteins of plasma membranes isolated from rat liver was significantly increased by several naphthoquinones including menadione. This apparent stimulation of membrane-associated protein kinase activity by these compounds was most striking (up to 6-7 fold) when the synthetic copolymers containing glutamate and tyrosine residues (4:1) was used as substrate. Since tyrosine residues are the only possible phosphate acceptor in the copolymers, the quinone-stimulated liver membrane protein kinase is most likely tyrosine specific. Although not required for protein kinase activity, dithiothreitol (DTT) was necessary for its stimulation by these quinonoid compounds. Hydrolysis of ATP was not significantly affected by quinones under the experimental conditions. Both menadione and vitamin k 5 increased phosphorylation of plasma membrane proteins of molecular weight 45 and 60 kd. The stimulatory effect of menadione on protein phosphorylation was prevented by the addition of superoxide dismutase. Dihydroxyfumerate, which spontaneously produces various radical species, and H 2 O 2 , also stimulated tyrosine-specific protein phosphorylation. DTT was also required for their full effect. It, therefore, appears that quinonone stimulation of tyrosine-specific protein phosphorylation is mediated by oxygen radicals

  9. DDB1-Mediated CRY1 Degradation Promotes FOXO1-Driven Gluconeogenesis in Liver.

    Science.gov (United States)

    Tong, Xin; Zhang, Deqiang; Charney, Nicholas; Jin, Ethan; VanDommelen, Kyle; Stamper, Kenneth; Gupta, Neil; Saldate, Johnny; Yin, Lei

    2017-10-01

    Targeted protein degradation through ubiquitination is an important step in the regulation of glucose metabolism. Here, we present evidence that the DDB1-CUL4A ubiquitin E3 ligase functions as a novel metabolic regulator that promotes FOXO1-driven hepatic gluconeogenesis. In vivo, hepatocyte-specific Ddb1 deletion leads to impaired hepatic gluconeogenesis in the mouse liver but protects mice from high-fat diet-induced hyperglycemia. Lack of Ddb1 downregulates FOXO1 protein expression and impairs FOXO1-driven gluconeogenic response. Mechanistically, we discovered that DDB1 enhances FOXO1 protein stability via degrading the circadian protein cryptochrome 1 (CRY1), a known target of DDB1 E3 ligase. In the Cry1 depletion condition, insulin fails to reduce the nuclear FOXO1 abundance and suppress gluconeogenic gene expression. Chronic depletion of Cry1 in the mouse liver not only increases FOXO1 protein but also enhances hepatic gluconeogenesis. Thus, we have identified the DDB1-mediated CRY1 degradation as an important target of insulin action on glucose homeostasis. © 2017 by the American Diabetes Association.

  10. Oxidative stress-mediated mouse liver lesions caused by Clonorchis sinensis infection.

    Science.gov (United States)

    Maeng, Sejung; Lee, Hye Won; Bashir, Qudsia; Kim, Tae Im; Hong, Sung-Jong; Lee, Tae Jin; Sohn, Woon-Mok; Na, Byoung-Kuk; Kim, Tong-Soo; Pak, Jhang Ho

    2016-03-01

    Clonorchis sinensis is a high-risk pathogenic helminth that strongly provokes inflammation, epithelial hyperplasia, periductal fibrosis, and even cholangiocarcinoma in chronically infected individuals. Chronic inflammation is associated with an increased risk of various cancers due to the disruption of redox homeostasis. Accordingly, the present study was conducted to examine the time course relationship between histopathological changes and the appearance of oxidative stress markers, including lipid peroxidation, enzymes involved in lipid peroxidation, and mutagenic DNA adducts in the livers of mice infected with C. sinensis, as well as proinflammatory cytokines in infected mouse sera. Histopathological phenotypes such as bile duct epithelial hyperplasia, periductal fibrosis, edema and inflammatory infiltration increased in infected livers in a time-dependent manner. Intense immunoreactivity of lipid peroxidation products (4-hydroxy-2-nonenal; malondialdehyde), cyclooxygenase-2, 5-lipoxygenase and 8-oxo-7,8-dihydro-2'-deoxyguanosine were concomitantly observed in these injured regions. We also found elevated expressions of cyclooxygenase-2 and 5-lipoxygenase in C. sinensis excretory-secretory product-treated cholangiocarcinoma cells. Moreover, the levels of proinflammatory cytokines such as TNF-α, ILβ-1 and IL-6 were differentially upregulated in infected sera. With regard to oxidative stress-mediated carcinogenesis, our findings suggest that C. sinensis infestation may disrupt host redox homeostasis, creating a damaging environment that favors the development of advanced hepatobiliary diseases such as clonorchiasis-associated cholangiocarcinoma. Copyright © 2015 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

  11. Adenovirus-mediated IL-12 gene therapy in combination with radiotherapy for murine liver cancer

    International Nuclear Information System (INIS)

    Wei Daoyan; Dai Bingbing; Wang Zhonghe; Chen Shishu

    2001-01-01

    Objective: To investigate the synergistic antitumor effects of adenovirus-mediated IL-12 gene therapy in combination with radiotherapy in mice bearing liver cancer. Methods: Balb/c mice bearing liver cancer received the treatment at day 1 with tumor local irradiation (TLI) of 20 Gy or mask irradiation when tumor size reached 0.6-1.0 cm. Within 1 hour after irradiation, adenovirus containing IL-12 gene or PBS was intra-tumor injected once a week. Forty-eight hours after the second injection, IFN-γ levels in sera and the supernatant of cultured spleen cells were assayed by ELISA, CTL activity of spleen cells was measured by 3 H-TdR release assay, and phenotypes of tumor-infiltrating lymphocytes were analysed by immunohistochemical staining. Results: The growth of tumors in animals treated with a combination of IL-12 gene therapy and TLI was inhibited more significantly than those with either single treatment (P + and CD8 + lymphocyte infiltration and tumor-specific cytolytic activities, and the levels of IFN-γ in sera were higher in IL-12 gene therapy and IL-12 gene therapy combined with TLI groups. Conclusion: These results suggest that IL-12 gene therapy combined with radiotherapy is more effective than both single treatment modalities and can induce specific antitumor immuno-response greatly

  12. Gut Microbiota Promotes Obesity-Associated Liver Cancer through PGE2-Mediated Suppression of Antitumor Immunity.

    Science.gov (United States)

    Loo, Tze Mun; Kamachi, Fumitaka; Watanabe, Yoshihiro; Yoshimoto, Shin; Kanda, Hiroaki; Arai, Yuriko; Nakajima-Takagi, Yaeko; Iwama, Atsushi; Koga, Tomoaki; Sugimoto, Yukihiko; Ozawa, Takayuki; Nakamura, Masaru; Kumagai, Miho; Watashi, Koichi; Taketo, Makoto M; Aoki, Tomohiro; Narumiya, Shuh; Oshima, Masanobu; Arita, Makoto; Hara, Eiji; Ohtani, Naoko

    2017-05-01

    Obesity increases the risk of cancers, including hepatocellular carcinomas (HCC). However, the precise molecular mechanisms through which obesity promotes HCC development are still unclear. Recent studies have shown that gut microbiota may influence liver diseases by transferring its metabolites and components. Here, we show that the hepatic translocation of obesity-induced lipoteichoic acid (LTA), a Gram-positive gut microbial component, promotes HCC development by creating a tumor-promoting microenvironment. LTA enhances the senescence-associated secretory phenotype (SASP) of hepatic stellate cells (HSC) collaboratively with an obesity-induced gut microbial metabolite, deoxycholic acid, to upregulate the expression of SASP factors and COX2 through Toll-like receptor 2. Interestingly, COX2-mediated prostaglandin E 2 (PGE 2 ) production suppresses the antitumor immunity through a PTGER4 receptor, thereby contributing to HCC progression. Moreover, COX2 overexpression and excess PGE 2 production were detected in HSCs in human HCCs with noncirrhotic, nonalcoholic steatohepatitis (NASH), indicating that a similar mechanism could function in humans. Significance: We showed the importance of the gut-liver axis in obesity-associated HCC. The gut microbiota-driven COX2 pathway produced the lipid mediator PGE 2 in senescent HSCs in the tumor microenvironment, which plays a pivotal role in suppressing antitumor immunity, suggesting that PGE 2 and its receptor may be novel therapeutic targets for noncirrhotic NASH-associated HCC. Cancer Discov; 7(5); 522-38. ©2017 AACR. This article is highlighted in the In This Issue feature, p. 443 . ©2017 American Association for Cancer Research.

  13. Adrenalectomy mediated alterations in adrenergic activation of adenylate cyclase in rat liver

    International Nuclear Information System (INIS)

    El-Refai, M.; Chan, T.

    1986-01-01

    Adrenalectomy caused a large increase in the number of β-adrenergic binding sites on liver plasma membranes as measured by 125 I-iodocyanopindolol (22 and 102 fmol/mg protein for control and adrenalectomized (ADX) rats). Concomitantly an increase in the number of binding sites for 3 H-yohimbine was also observed (104 and 175 fmol/mg protein for control and adx membranes). Epinephrine-stimulated increase in cyclic AMP accumulation in isolated hepatocytes were greater in cells from ADX rats. This increase in β-adrenergic mediated action was much less than what may be expected as a result of the increase in the β-adrenergic binding in ADX membranes. In addition phenoxybenzamine (10 μM) further augmented this action of epinephrine in both control and ADX cells. To test the hypothesis that the increase in the number of the inhibitory α 2 -adrenergic receptors in adrenalectomy is responsible for the muted β-adrenergic response, the authors injected rats with pertussis toxin (PT). This treatment may cause the in vivo ribosylation of the inhibitory binding protein (Ni). Adenylate cyclase (AC) activity in liver plasma membranes prepared from treated and untreated animals was measured. In contrast with control rats, treatment of ADX rats with PT resulted in a significant increase in the basal activity of AC (5.5 and 7.7 pmol/mg protein/min for untreated and treated rats respectively). Isoproterenol (10 μM), caused AC activity to increase to 6.5 and 8.4 pmol/mg protein/min for membranes obtained from ADX untreated and ADX treated rats respectively. The α-adrenergic antagonists had no significant effect on the β-adrenergic-mediated activation of AC in liver plasma membranes from PT treated control and ADX rats. The authors conclude that the β-adrenergic activation of AC is attenuated by Ni protein both directly and as a result of activation of α-adrenergic receptors

  14. Effects of o-aminoazotoluene on liver regeneration and p53 activation in mice susceptible and resistant to hepatocarcinogenesis

    International Nuclear Information System (INIS)

    Timofeeva, Olga A.; Eremeev, Artem V.; Goloshchapov, Andrey; Kalashnikova, Eugenia; Ilnitskaya, Svetlana; Setkov, Nikolai A.; Kobzev, Victor; Buzard, Gregory S.; Filipenko, Maxim L.; Kaledin, Vasily I.; Merkulova, Tatyana I.

    2008-01-01

    The susceptibility to hepatocellular carcinoma (HCC) varies greatly within human populations in response to environmental risk agents. The mechanisms underlying differential susceptibility are still largely unknown and need to be clarified to improve HCC chemoprevention and therapeutic treatment. Inbred rodent strains with established predispositions for hepatocarcinogenesis offer the opportunity to identify intrinsic susceptibility and resistance factors. Previously, we have characterized mouse strains showing differential susceptibility to o-aminoazotoluene (OAT) and established that susceptibility does not result from OAT metabolism or genotoxicity in the livers of resistant and susceptible mice. In this study we have found that OAT differently affects hepatocyte proliferation in mice after partial hepatectomy (PH). OAT inhibited hepatocyte proliferation by 60-80% in the livers of susceptible mice, whereas resistant mice showed less than 15% inhibition. The inhibition resulted in significant delay of hepatic mass recovery in susceptible mice. OAT induced p53 stabilization and transcriptional activation in response to carcinogen treatment to the same degree in both, susceptible and resistant mice. Taken together, our data support inhibition of hepatocyte proliferation as a major cause for increased mouse susceptibility to hepatocarcinogenesis, and acceleration of functional liver recovery may offer a way to increase resistance to hepatic neoplasms. These results may have relevance to clinical observations of HCCs and implications for HCC chemoprevention and treatment

  15. Fibronectin Extra Domain A Promotes Liver Sinusoid Repair following Hepatectomy.

    Directory of Open Access Journals (Sweden)

    Bridget Sackey-Aboagye

    Full Text Available Liver sinusoidal endothelial cells (LSECs are the main endothelial cells in the liver and are important for maintaining liver homeostasis as well as responding to injury. LSECs express cellular fibronectin containing the alternatively spliced extra domain A (EIIIA-cFN and increase expression of this isoform after liver injury, although its function is not well understood. Here, we examined the role of EIIIA-cFN in liver regeneration following partial hepatectomy. We carried out two-thirds partial hepatectomies in mice lacking EIIIA-cFN and in their wild type littermates, studied liver endothelial cell adhesion on decellularized, EIIIA-cFN-containing matrices and investigated the role of cellular fibronectins in liver endothelial cell tubulogenesis. We found that liver weight recovery following hepatectomy was significantly delayed and that sinusoidal repair was impaired in EIIIA-cFN null mice, especially females, as was the lipid accumulation typical of the post-hepatectomy liver. In vitro, we found that liver endothelial cells were more adhesive to cell-deposited matrices containing the EIIIA domain and that cellular fibronectin enhanced tubulogenesis and vascular cord formation. The integrin α9β1, which specifically binds EIIIA-cFN, promoted tubulogenesis and adhesion of liver endothelial cells to EIIIA-cFN. Our findings identify a role for EIIIA-cFN in liver regeneration and tubulogenesis. We suggest that sinusoidal repair is enhanced by increased LSEC adhesion, which is mediated by EIIIA-cFN.

  16. Augmenter of liver regeneration inhibits TGF-β1-induced renal tubular epithelial-to-mesenchymal transition via suppressing TβR II expression in vitro

    International Nuclear Information System (INIS)

    Liao, Xiao-hui; Zhang, Ling; Chen, Guo-tao; Yan, Ru-yu; Sun, Hang; Guo, Hui; Liu, Qi

    2014-01-01

    Tubular epithelial-to-mesenchymal transition (EMT) plays a crucial role in the progression of renal tubular interstitial fibrosis (TIF), which subsequently leads to chronic kidney disease (CKD) and eventually, end-stage renal disease (ESRD). We propose that augmenter of liver regeneration (ALR), a member of the newly discovered ALR/Erv1 protein family shown to ameliorate hepatic fibrosis, plays a similar protective role in renal tubular cells and has potential as a new treatment option for CKD. Here, we showed that recombinant human ALR (rhALR) inhibits EMT in renal tubular cells by antagonizing activation of the transforming growth factor-β1 (TGF-β1) signaling pathway. Further investigation revealed that rhALR suppresses the expression of TGF-β receptor type II (TβR II) and significantly alleviates TGF-β1-induced phosphorylation of Smad2 and nuclear factor-κB (NF-κB). No apparent adverse effects were observed upon the addition of rhALR alone to cells. These findings collectively suggest that ALR plays a role in inhibiting progression of renal tubular EMT, supporting its potential utility as an effective antifibrotic strategy to reverse TIF in CKD. - Highlights: • ALR is involved in the pathological progression of renal EMT in NRK-52E cells. • ALR suppresses the expression of TβRII and the phosphorylation of Smad2 and NF-κB. • ALR plays a role in inhibiting progression of renal tubular EMT

  17. Augmenter of liver regeneration inhibits TGF-β1-induced renal tubular epithelial-to-mesenchymal transition via suppressing TβR II expression in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Liao, Xiao-hui [Department of Nephrology, The Second Affiliated Hospital, Chongqing Medical University, Chongqing 400010 (China); Zhang, Ling, E-mail: lindazhang8508@hotmail.com [Department of Nephrology, The Second Affiliated Hospital, Chongqing Medical University, Chongqing 400010 (China); Chen, Guo-tao; Yan, Ru-yu [Department of Nephrology, The Second Affiliated Hospital, Chongqing Medical University, Chongqing 400010 (China); Sun, Hang; Guo, Hui [Institute for Viral Hepatitis, Key Laboratory of Molecular Biology for Infectious Diseases, The Second Affiliated Hospital, Chongqing Medical University, Chongqing 400010 (China); Liu, Qi, E-mail: txzzliuqi@163.com [Institute for Viral Hepatitis, Key Laboratory of Molecular Biology for Infectious Diseases, The Second Affiliated Hospital, Chongqing Medical University, Chongqing 400010 (China)

    2014-10-01

    Tubular epithelial-to-mesenchymal transition (EMT) plays a crucial role in the progression of renal tubular interstitial fibrosis (TIF), which subsequently leads to chronic kidney disease (CKD) and eventually, end-stage renal disease (ESRD). We propose that augmenter of liver regeneration (ALR), a member of the newly discovered ALR/Erv1 protein family shown to ameliorate hepatic fibrosis, plays a similar protective role in renal tubular cells and has potential as a new treatment option for CKD. Here, we showed that recombinant human ALR (rhALR) inhibits EMT in renal tubular cells by antagonizing activation of the transforming growth factor-β1 (TGF-β1) signaling pathway. Further investigation revealed that rhALR suppresses the expression of TGF-β receptor type II (TβR II) and significantly alleviates TGF-β1-induced phosphorylation of Smad2 and nuclear factor-κB (NF-κB). No apparent adverse effects were observed upon the addition of rhALR alone to cells. These findings collectively suggest that ALR plays a role in inhibiting progression of renal tubular EMT, supporting its potential utility as an effective antifibrotic strategy to reverse TIF in CKD. - Highlights: • ALR is involved in the pathological progression of renal EMT in NRK-52E cells. • ALR suppresses the expression of TβRII and the phosphorylation of Smad2 and NF-κB. • ALR plays a role in inhibiting progression of renal tubular EMT.

  18. Potential for drug interactions mediated by polymorphic flavin-containing monooxygenase 3 in human livers.

    Science.gov (United States)

    Shimizu, Makiko; Shiraishi, Arisa; Sato, Ayumi; Nagashima, Satomi; Yamazaki, Hiroshi

    2015-02-01

    Human flavin-containing monooxygenase 3 (FMO3) in the liver catalyzes a variety of oxygenations of nitrogen- and sulfur-containing medicines and xenobiotic substances. Because of growing interest in drug interactions mediated by polymorphic FMO3, benzydamine N-oxygenation by human FMO3 was investigated as a model reaction. Among the 41 compounds tested, trimethylamine, methimazole, itopride, and tozasertib (50 μM) suppressed benzydamine N-oxygenation at a substrate concentration of 50 μM by approximately 50% after co-incubation. Suppression of N-oxygenation of benzydamine, trimethylamine, itopride, and tozasertib and S-oxygenation of methimazole and sulindac sulfide after co-incubation with the other five of these six substrates was compared using FMO3 proteins recombinantly expressed in bacterial membranes. Apparent competitive inhibition by methimazole (0-50 μM) of sulindac sulfide S-oxygenation was observed with FMO3 proteins. Sulindac sulfide S-oxygenation activity of Arg205Cys variant FMO3 protein was likely to be suppressed more by methimazole than wild-type or Val257Met variant FMO3 protein was. These results suggest that genetic polymorphism in the human FMO3 gene may lead to changes of drug interactions for N- or S-oxygenations of xenobiotics and endogenous substances and that a probe battery system of benzydamine N-oxygenation and sulindac sulfide S-oxygenation activities is recommended to clarify the drug interactions mediated by FMO3. Copyright © 2014 The Japanese Society for the Study of Xenobiotics. Published by Elsevier Ltd. All rights reserved.

  19. Advances in ultrasound-targeted microbubble–mediated gene therapy for liver fibrosis

    OpenAIRE

    Huang, Cuiyuan; Zhang, Hong; Bai, Ruidan

    2017-01-01

    Hepatic fibrosis develops as a wound-healing scar in response to acute and chronic liver inflammation and can lead to cirrhosis in patients with chronic hepatitis B and C. The condition arises due to increased synthesis and reduced degradation of extracellular matrix (ECM) and is a common pathological sequela of chronic liver disease. Excessive deposition of ECM in the liver causes liver dysfunction, ascites, and eventually upper gastrointestinal bleeding as well as a series of complications....

  20. microRNA 21-mediated suppression of Sprouty1 by Pokemon affects liver cancer cell growth and proliferation.

    Science.gov (United States)

    Jin, Xiu-Li; Sun, Qin-Sheng; Liu, Feng; Yang, Hong-Wei; Liu, Min; Liu, Hong-Xia; Xu, Wei; Jiang, Yu-Yang

    2013-07-01

    Transcriptional repressor Pokemon is a critical factor in embryogenesis, development, cell proliferation, differentiation, and oncogenesis, thus behaving as an oncogene. Oncomine database suggests a potential correlation between the expressions of Pokemon and Sprouty1. This study investigated the regulatory role of Pokemon in Sprouty1 expression and the effect on liver cancer cell growth and proliferation, revealing a novel miR-21-mediated regulatory circuit. In normal (HL-7702) and cancer (QGY-7703) liver cell lines, Sprouty1 expression is inversely correlated with Pokemon levels. Targeted expression or siRNA-mediated silencing showed that Pokemon is a repressor of Sprouty1 expression at both mRNA and protein levels, but Pokemon cannot affect the promoter activity of Sprouty1. Sprouty1 is a target of miR-21 and interestingly, we found that miR-21 is up-regulated by Pokemon in liver cancer cells. Luciferase reporter assays showed that Pokemon up-regulated miR-21 transcription in a dose-dependent manner, and ChIP assay exhibited a direct binding of Pokemon to the miR-21 promoter at -747 to -399 bp. Site-directed mutagenesis of the GC boxes at -684 to -679 bp and -652 to -647 bp of miR-21 promoter abolished the regulatory activity by Pokemon. Furthermore, we found that the modulation of Pokemon and miR-21 expression affected the growth and proliferation of liver cancer cells QGY-7703. In summary, our findings demonstrate that Pokemon suppresses Sprouty1 expression through a miR-21-mediated mechanism, affecting the growth and proliferation of liver cancer cells. This study recognized miR-21 and Sprouty1 as novel targets of the Pokemon regulatory network. Copyright © 2013 Wiley Periodicals, Inc.

  1. Circulating histones are major mediators of systemic inflammation and cellular injury in patients with acute liver failure.

    Science.gov (United States)

    Wen, Zongmei; Lei, Zhen; Yao, Lu; Jiang, Ping; Gu, Tao; Ren, Feng; Liu, Yan; Gou, Chunyan; Li, Xiuhui; Wen, Tao

    2016-09-29

    Acute liver failure (ALF) is a life-threatening systemic disorder. Here we investigated the impact of circulating histones, recently identified inflammatory mediators, on systemic inflammation and liver injury in murine models and patients with ALF. We analyzed histone levels in blood samples from 62 patients with ALF, 60 patients with chronic liver disease, and 30 healthy volunteers. We incubated patients' sera with human L02 hepatocytes and monocytic U937 cells to assess cellular damage and cytokine production. d-galactosamine plus lipopolysaccharide (GalN/LPS), concanavalin A (ConA), and acetaminophen (APAP) were given to C57BL/6N mice to induce liver injury, respectively, and the pathogenic role of circulating histones was studied. Besides, the protective effect of nonanticoagulant heparin, which can bind histones, was evaluated with in vivo and ex vivo investigations. We observed that circulating histones were significantly increased in patients with ALF, and correlated with disease severity and mortality. Significant systemic inflammation was also pronounced in ALF patients, which were associated with histone levels. ALF patients' sera induced significant L02 cell death and stimulated U937 cells to produce cytokines, which were abrogated by nonanticoagulant heparin. Furthermore, circulating histones were all released remarkably in GalN/LPS, ConA, and APAP-treated mice, and associated with high levels of inflammatory cytokines. Heparin reduced systemic inflammation and liver damage in mice, suggesting that it could interfere with histone-associated liver injury. Collectively, these findings demonstrate that circulating histones are critical mediators of systemic inflammation and cellular damage in ALF, which may be potentially translatable for clinical use.

  2. Suppression of Oncolytic Adenovirus-Mediated Hepatotoxicity by Liver-Specific Inhibition of NF-κB

    Directory of Open Access Journals (Sweden)

    Mitsuhiro Machitani

    2017-12-01

    Full Text Available Telomerase-specific replication-competent adenoviruses (Ads, i.e., TRADs, which possess an E1 gene expression cassette driven by the human telomerase reverse transcriptase promoter, are promising agents for cancer treatment. However, even though oncolytic Ads, including TRAD, are intratumorally administered, they are disseminated from the tumor to systemic circulation, causing concern about oncolytic Ad-mediated hepatotoxicity (due mainly to leaky expression of Ad genes in liver. We reported that inhibition of nuclear factor-κB (NF-κB leads to the suppression of replication-incompetent Ad vector-mediated hepatotoxicity via reduction of the leaky expression of Ad genes in liver. Here, to develop a TRAD with an improved safety profile, we designed a TRAD that carries a liver-specific promoter-driven dominant-negative IκBα (DNIκBα expression cassette (TRAD-DNIκBα. Compared with a conventional TRAD, TRAD-DNIκBα showed hepatocyte-specific inhibition of NF-κB signaling and significantly reduced Ad gene expression and replication in the normal human hepatocyte cell line. TRAD-induced hepatotoxicity was largely suppressed in mice following intravenous administration of TRAD-DNIκBα. However, the replication profiles and oncolytic activities of TRAD-DNIκBα were comparable with those of the conventional TRAD in human non-hepatic tumor cells. These results indicate that oncolytic Ads containing the liver-specific DNIκBα expression cassette have improved safety profiles without inhibiting oncolytic activities.

  3. Atorvastatin reduces lipid accumulation in the liver by activating protein kinase A-mediated phosphorylation of perilipin 5.

    Science.gov (United States)

    Gao, Xing; Nan, Yang; Zhao, Yuanlin; Yuan, Yuan; Ren, Bincheng; Sun, Chao; Cao, Kaiyu; Yu, Ming; Feng, Xuyang; Ye, Jing

    2017-12-01

    Statins have been proven to be effective in treating non-alcoholic fatty liver disease (NAFLD). Recently, it was reported that statins decreased the hepatic expression of perilipin 5 (Plin5), a lipid droplet (LD)-associated protein, which plays critical roles in regulating lipid accumulation and lipolysis in liver. However, the function and regulation mechanism of Plin5 have not yet been well-established in NAFLD treatment with statins. In this study, we observed that atorvastatin moderately reduced the expression of Plin5 in livers without changing the protein level of Plin5 in the hepatic LD fraction of mice fed with high-fat diet (HFD). Intriguingly, atorvastatin stimulated the PKA-mediated phosphorylation of Plin5 and reduced the triglyceride (TG) accumulation in hepatocytes with overexpression of wide type (Plin5-WT) compared to serine-155 mutant Plin5 (Plin5-S155A). Moreover, PKA-stimulated FA release of purified LDs carrying Plin5-WT but not Plin5-S155A. Glucagon, a PKA activator, stimulated the phosphorylation of Plin5-WT and inhibited its interaction with CGI-58. The results indicated that atorvastatin promoted lipolysis and reduced TG accumulation in the liver by increasing PKA-mediated phosphorylation of Plin5. This new mechanism of lipid-lowering effects of atorvastatin might provide a new strategy for NAFLD treatment. Copyright © 2017. Published by Elsevier B.V.

  4. Improved axonal regeneration of transected spinal cord mediated by multichannel collagen conduits functionalized with neurotrophin-3 gene.

    Science.gov (United States)

    Yao, L; Daly, W; Newland, B; Yao, S; Wang, W; Chen, B K K; Madigan, N; Windebank, A; Pandit, A

    2013-12-01

    Functionalized biomaterial scaffolds targeted at improving axonal regeneration by enhancing guided axonal growth provide a promising approach for the repair of spinal cord injury. Collagen neural conduits provide structural guidance for neural tissue regeneration, and in this study it is shown that these conduits can also act as a reservoir for sustained gene delivery. Either a G-luciferase marker gene or a neurotrophin-3-encoding gene, complexed to a non-viral, cyclized, PEGylated transfection vector, was loaded within a multichannel collagen conduit. The complexed genes were then released in a controlled fashion using a dual release system both in vitro and in vivo. For evaluation of their biological performance, the loaded conduits were implanted into the completely transected rat thoracic spinal cord (T8-T10). Aligned axon regeneration through the channels of conduits was observed one month post-surgery. The conduits delivering neurotrophin-3 polyplexes resulted in significantly increased neurotrophin-3 levels in the surrounding tissue and a statistically higher number of regenerated axons versus the control conduits (P<0.05). This study suggests that collagen neural conduits delivering a highly effective non-viral therapeutic gene may hold promise for repair of the injured spinal cord.

  5. Retinoic Acid Signaling Mediates Hair Cell Regeneration by Repressing p27kip and sox2 in Supporting Cells.

    Science.gov (United States)

    Rubbini, Davide; Robert-Moreno, Àlex; Hoijman, Esteban; Alsina, Berta

    2015-11-25

    During development, otic sensory progenitors give rise to hair cells and supporting cells. In mammalian adults, differentiated and quiescent sensory cells are unable to generate new hair cells when these are lost due to various insults, leading to irreversible hearing loss. Retinoic acid (RA) has strong regenerative capacity in several organs, but its role in hair cell regeneration is unknown. Here, we use genetic and pharmacological inhibition to show that the RA pathway is required for hair cell regeneration in zebrafish. When regeneration is induced by laser ablation in the inner ear or by neomycin treatment in the lateral line, we observe rapid activation of several components of the RA pathway, with dynamics that position RA signaling upstream of other signaling pathways. We demonstrate that blockade of the RA pathway impairs cell proliferation of supporting cells in the inner ear and lateral line. Moreover, in neuromast, RA pathway regulates the transcription of p27(kip) and sox2 in supporting cells but not fgf3. Finally, genetic cell-lineage tracing using Kaede photoconversion demonstrates that de novo hair cells derive from FGF-active supporting cells. Our findings reveal that RA has a pivotal role in zebrafish hair cell regeneration by inducing supporting cell proliferation, and shed light on the underlying transcriptional mechanisms involved. This signaling pathway might be a promising approach for hearing recovery. Hair cells are the specialized mechanosensory cells of the inner ear that capture auditory and balance sensory input. Hair cells die after acoustic trauma, ototoxic drugs or aging diseases, leading to progressive hearing loss. Mammals, in contrast to zebrafish, lack the ability to regenerate hair cells. Here, we find that retinoic acid (RA) pathway is required for hair cell regeneration in vivo in the zebrafish inner ear and lateral line. RA pathway is activated very early upon hair cell loss, promotes cell proliferation of progenitor cells

  6. Sutureless liver repair and hemorrhage control using laser-mediated fusion of human albumin as a solder.

    Science.gov (United States)

    Wadia, Y; Xie, H; Kajitani, M

    2001-07-01

    Major liver trauma has a high mortality because of immediate exsanguination and a delayed morbidity from septicemia, peritonitis, biliary fistulae, and delayed secondary hemorrhage. We evaluated laser soldering using liquid albumin for welding liver injuries. Fourteen lacerations (6 x 2 cm) and 13 nonanatomic resection injuries (raw surface, 8 x 2 cm) were repaired. An 805-nm laser was used to weld 53% liquid albumin-indocyanine green solder to the liver surface, reinforcing it by welding a free autologous omental scaffold. The animals were heparinized and hepatic inflow occlusion was used for vascular control. For both laceration and resection injuries, 16 soldering repairs were evaluated acutely at 3 hours. Eleven animals were evaluated chronically, two at 2 weeks and nine at 4 weeks. All 27 laser mediated-liver repairs had minimal blood loss compared with the suture controls. No dehiscence, hemorrhage, or bile leakage was seen in any of the laser repairs after 3 hours. All 11 chronic repairs healed without complication. This modality effectively seals the liver surface, joins lacerations with minimal thermal injury, and works independently of the patient's coagulation status.

  7. Effect of baicalin on toll-like receptor 4-mediated ischemia/reperfusion inflammatory responses in alcoholic fatty liver condition

    International Nuclear Information System (INIS)

    Kim, Seok-Joo; Lee, Sun-Mee

    2012-01-01

    Alcoholic fatty liver is susceptible to secondary stresses such as ischemia/reperfusion (I/R). Baicalin is an active component extracted from Scutellaria baicalensis, which is widely used in herbal preparations for treatment of hepatic diseases and inflammatory disorders. This study evaluated the potential beneficial effect of baicalin on I/R injury in alcoholic fatty liver. Rats were fed an alcohol liquid diet or a control isocaloric diet for 5 weeks, and then subjected to 60 min of hepatic ischemia and 5 h of reperfusion. Baicalin (200 mg/kg) was intraperitoneally administered 24 and 1 h before ischemia. After reperfusion, baicalin attenuated the increases in serum alanine aminotransferase activity, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) levels in alcoholic fatty liver. The increased levels of TNF-α and IL-6 mRNA expression and inducible nitric oxide synthase and cyclooxygenase-2 protein and mRNA expressions increased after reperfusion, which were higher in ethanol-fed animals, were attenuated by baicalin. In ethanol-fed animals, baicalin attenuated the increases in toll-like receptor 4 (TLR4) and myeloid differentiation factor 88 protein expressions and the nuclear translocation of NF-κB after reperfusion. In conclusion, our findings suggest that baicalin ameliorates I/R-induced hepatocellular damage by suppressing TLR4-mediated inflammatory responses in alcoholic fatty liver. -- Highlights: ► Baicalin attenuates hepatic I/R-induced inflammation in alcoholic fatty liver. ► Baicalin downregulates TLR4, MyD88 expression during I/R in alcoholic fatty liver. ► Baicalin attenuates NF-κB nuclear translocation during I/R in alcoholic fatty liver.

  8. Enhanced antioxidant capacity of dental pulp-derived iPSC-differentiated hepatocytes and liver regeneration by injectable HGF-releasing hydrogel in fulminant hepatic failure.

    Science.gov (United States)

    Chiang, Chih-Hung; Wu, Wai-Wah; Li, Hsin-Yang; Chien, Yueh; Sun, Cho-Chin; Peng, Chi-Hsien; Lin, Alex Tong-Long; Huang, Chi-Shuan; Lai, Ying-Hsiu; Chiou, Shih-Hwa; Hung, Shuen-Iu; Chang, Yuh-Lih; Lan, Yuan-Tzu; Liu, Dean-Mo; Chien, Chian-Shiu; Huo, Teh-Ia; Lee, Shou-Dong; Wang, Chien-Ying

    2015-01-01

    Acute hepatic failure (AHF) is a severe liver injury leading to sustained damage and complications. Induced pluripotent stem cells (iPSCs) may be an alternative option for the treatment of AHF. In this study, we reprogrammed human dental pulp-derived fibroblasts into iPSCs, which exhibited pluripotency and the capacity to differentiate into tridermal lineages, including hepatocyte-like cells (iPSC-Heps). These iPSC-Heps resembled human embryonic stem cell-derived hepatocyte-like cells in gene signature and hepatic markers/functions. To improve iPSC-Heps engraftment, we next developed an injectable carboxymethyl-hexanoyl chitosan hydrogel (CHC) with sustained hepatocyte growth factor (HGF) release (HGF-CHC) and investigated the hepatoprotective activity of HGF-CHC-delivered iPSC-Heps in vitro and in an immunocompromised AHF mouse model induced by thioacetamide (TAA). Intrahepatic delivery of HGF-CHC-iPSC-Heps reduced the TAA-induced hepatic necrotic area and rescued liver function and recipient viability. Compared with PBS-delivered iPSC-Heps, the HGF-CHC-delivered iPSC-Heps exhibited higher antioxidant and antiapoptotic activities that reduced hepatic necrotic area. Importantly, these HGF-CHC-mediated responses could be abolished by administering anti-HGF neutralizing antibodies. In conclusion, our findings demonstrated that HGF mediated the enhancement of iPSC-Hep antioxidant/antiapoptotic capacities and hepatoprotection and that HGF-CHC is as an excellent vehicle for iPSC-Hep engraftment in iPSC-based therapy against AHF.

  9. 2,3,7,8-TCDD enhances the sensitivity of mice to concanavalin A immune-mediated liver injury

    Energy Technology Data Exchange (ETDEWEB)

    Fullerton, Aaron M., E-mail: fuller22@msu.edu [Department of Pharmacology and Toxicology, Center for Integrative Toxicology, Michigan State University, 1129 Farm Lane, Room 215, East Lansing, MI 48824 (United States); Roth, Robert A., E-mail: rothr@msu.edu [Department of Pharmacology and Toxicology, Center for Integrative Toxicology, Michigan State University, Food Safety and Toxicology Building, 1129 Farm Lane, Room 221, East Lansing, MI 48824 (United States); Ganey, Patricia E., E-mail: ganey@msu.edu [Department of Pharmacology and Toxicology, Center for Integrative Toxicology, Michigan State University, Food Safety and Toxicology Building, 1129 Farm Lane, Room 214, East Lansing, MI 48824 (United States)

    2013-01-15

    Inflammation plays a major role in immune-mediated liver injury, and exposure to environmental pollutants such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has been reported to alter the inflammatory response as well as affect immune cell activity. In this study, we tested the hypothesis that TCDD pretreatment exacerbates hepatotoxicity in a murine model of immune-mediated liver injury induced by concanavalin A (Con A) administration. Mice were pretreated with 30 μg/kg TCDD or vehicle control on day zero and then given either Con A or saline intravenously on day four. Mice treated with TCDD did not develop liver injury; however, TCDD pretreatment increased liver injury resulting from moderate doses of Con A (4–10 mg/kg). TCDD-pretreated mice had altered plasma concentrations of inflammatory cytokines, including interferon gamma (IFNγ), and TCDD/Con A-induced hepatotoxicity was attenuated in IFNγ knockout mice. At various times after treatment, intrahepatic immune cells were isolated, and expression of cell activation markers as well as cytolytic proteins was determined. TCDD pretreatment increased the proportion of activated natural killer T (NKT) cells and the percent of cells expressing Fas ligand (FasL) after Con A administration. In addition FasL knockout mice and mice treated with CD18 antiserum were both protected from TCDD/Con A-induced hepatotoxicity, suggesting a requirement for direct cell–cell interaction between effector immune cells and parenchymal cell targets in the development of liver injury from TCDD/Con A treatment. In summary, exposure to TCDD increased NKT cell activation and exacerbated immune-mediated liver injury induced by Con A through a mechanism involving IFNγ and FasL expression. -- Highlights: ► TCDD pretreatment sensitizes mice to Con A-induced hepatotoxicity. ► TCDD pretreatment increased concentration of IFNγ in plasma after Con A. ► Con A-induced activation of NKT cells was increased by TCDD pretreatment. ► Fas

  10. 2,3,7,8-TCDD enhances the sensitivity of mice to concanavalin A immune-mediated liver injury

    International Nuclear Information System (INIS)

    Fullerton, Aaron M.; Roth, Robert A.; Ganey, Patricia E.

    2013-01-01

    Inflammation plays a major role in immune-mediated liver injury, and exposure to environmental pollutants such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has been reported to alter the inflammatory response as well as affect immune cell activity. In this study, we tested the hypothesis that TCDD pretreatment exacerbates hepatotoxicity in a murine model of immune-mediated liver injury induced by concanavalin A (Con A) administration. Mice were pretreated with 30 μg/kg TCDD or vehicle control on day zero and then given either Con A or saline intravenously on day four. Mice treated with TCDD did not develop liver injury; however, TCDD pretreatment increased liver injury resulting from moderate doses of Con A (4–10 mg/kg). TCDD-pretreated mice had altered plasma concentrations of inflammatory cytokines, including interferon gamma (IFNγ), and TCDD/Con A-induced hepatotoxicity was attenuated in IFNγ knockout mice. At various times after treatment, intrahepatic immune cells were isolated, and expression of cell activation markers as well as cytolytic proteins was determined. TCDD pretreatment increased the proportion of activated natural killer T (NKT) cells and the percent of cells expressing Fas ligand (FasL) after Con A administration. In addition FasL knockout mice and mice treated with CD18 antiserum were both protected from TCDD/Con A-induced hepatotoxicity, suggesting a requirement for direct cell–cell interaction between effector immune cells and parenchymal cell targets in the development of liver injury from TCDD/Con A treatment. In summary, exposure to TCDD increased NKT cell activation and exacerbated immune-mediated liver injury induced by Con A through a mechanism involving IFNγ and FasL expression. -- Highlights: ► TCDD pretreatment sensitizes mice to Con A-induced hepatotoxicity. ► TCDD pretreatment increased concentration of IFNγ in plasma after Con A. ► Con A-induced activation of NKT cells was increased by TCDD pretreatment. ► Fas

  11. Oval cell response is attenuated by depletion of liver resident macrophages in the 2-AAF/partial hepatectomy rat.

    Directory of Open Access Journals (Sweden)

    Shuai Xiang

    Full Text Available BACKGROUND/AIMS: Macrophages are known to play an important role in hepatocyte mediated liver regeneration by secreting inflammatory mediators. However, there is little information available on the role of resident macrophages in oval cell mediated liver regeneration. In the present study we aimed to investigate the role of macrophages in oval cell expansion induced by 2-acetylaminofluorene/partial hepatectomy (2-AAF/PH in rats. METHODOLOGY/PRINCIPAL FINDINGS: We depleted macrophages in the liver of 2-AAF/PH treated rats by injecting liposome encapsulated clodronate 48 hours before PH. Regeneration of remnant liver mass, as well as proliferation and differentiation of oval cells were measured. We found that macrophage-depleted rats suffered higher mortality and liver transaminase levels. We also showed that depletion of macrophages yielded a significant decrease of EPCAM and PCK positive oval cells in immunohistochemical stained liver sections 9 days after PH. Meanwhile, oval cell differentiation was also attenuated as a result of macrophage depletion, as large foci of small basophilic hepatocytes were observed by day 9 following hepatectomy in control rats whereas they were almost absent in macrophage depleted rats. Accordingly, real-time polymerase chain reaction analysis showed lower expression of albumin mRNA in macrophage depleted livers. Then we assessed whether macrophage depletion may affect hepatic production of stimulating cytokines for liver regeneration. We showed that macrophage-depletion significantly inhibited hepatic expression of tumor necrosis factor-α and interleukin-6, along with a lack of signal transducer and activator of transcription 3 phosphorylation during the early period following hepatectomy. CONCLUSIONS: These data indicate that macrophages play an important role in oval cell mediated liver regeneration in the 2-AAF/PH model.

  12. Targeting CCl4 -induced liver fibrosis by RNA interference-mediated inhibition of cyclin E1 in mice.

    Science.gov (United States)

    Bangen, Jörg-Martin; Hammerich, Linda; Sonntag, Roland; Baues, Maike; Haas, Ute; Lambertz, Daniela; Longerich, Thomas; Lammers, Twan; Tacke, Frank; Trautwein, Christian; Liedtke, Christian

    2017-10-01

    Initiation and progression of liver fibrosis requires proliferation and activation of resting hepatic stellate cells (HSCs). Cyclin E1 (CcnE1) is the regulatory subunit of the cyclin-dependent kinase 2 (Cdk2) and controls cell cycle re-entry. We have recently shown that genetic inactivation of CcnE1 prevents activation, proliferation, and survival of HSCs and protects from liver fibrogenesis. The aim of the present study was to translate these findings into preclinical applications using an RNA interference (RNAi)-based approach. CcnE1-siRNA (small interfering RNA) efficiently inhibited CcnE1 gene expression in murine and human HSC cell lines and in primary HSCs, resulting in diminished proliferation and increased cell death. In C57BL/6 wild-type (WT) mice, delivery of stabilized siRNA using a liposome-based carrier targeted approximately 95% of HSCs, 70% of hepatocytes, and 40% of CD45 + cells after single injection. Acute CCl 4 -mediated liver injury in WT mice induced endogenous CcnE1 expression and proliferation of surviving hepatocytes and nonparenchymal cells, including CD45 + leukocytes. Pretreatment with CcnE1-siRNA reverted CcnE1 induction to baseline levels of healthy mice, which was associated with reduced liver injury, diminished proliferation of hepatocytes and leukocytes, and attenuated overall inflammatory response. For induction of liver fibrosis, WT mice were challenged with CCl 4 for 4-6 weeks. Co-treatment with CcnE1-siRNA once a week was sufficient to continuously block CcnE1 expression and cell-cycle activity of hepatocytes and nonparenchymal cells, resulting in significantly ameliorated liver fibrosis and inflammation. Importantly, CcnE1-siRNA also prevented progression of liver fibrosis if applied after onset of chronic liver injury. Therapeutic targeting of CcnE1 in vivo using RNAi is feasible and has high antifibrotic activity. (Hepatology 2017;66:1242-1257). © 2017 by the American Association for the Study of Liver Diseases.

  13. Possible role of Arthrospira platensis in reversing oxidative stress-mediated liver damage in rats exposed to lead.

    Science.gov (United States)

    Khalil, Samah R; Elhady, Walaa M; Elewa, Yaser H A; Abd El-Hameed, Noura E; Ali, Sozan A

    2018-01-01

    Environmental pollutants, particularly metallic elements, mobilized and released into the environment, eventually accumulate in the food chain and thus pose a serious threat to human and animal health. In the present study, the role of Arthrospira (Spirulina platensis; SP) as a protector against oxidative stress-mediated liver damage induced by an exposure to lead acetate (LA; as a metallic pollutant) was assessed. To achieve this aim, rats were orally administered with 300 mg/kg bw SP for 15 days, before and concurrently with an intraperitoneal injection of 50 mg/kg bw LA (6 injections throughout 15 days). As a result, co-administration of SP with LA reduced the amount of lead that accumulated in both blood and liver tissue of the exposed rats and minimized the increased levels of lipid peroxidation, protein oxidation, DNA oxidative damage, and liver enzyme endpoints. In addition, because of SP administration, the levels of depleted biomarkers of antioxidant status and total antioxidant capacity in LA-exposed rats improved. Moreover, SP protected the liver tissue against the changes caused by LA exposure and also decreased the reactivity of HSP70 in the cytoplasm of hepatocytes. Collectively, our data suggest that SP has a potential use as a food supplement in the regions highly polluted with heavy metals such as lead. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  14. Hepatic FGF21 mediates sex differences in high-fat high-fructose diet-induced fatty liver.

    Science.gov (United States)

    Chukijrungroat, Natsasi; Khamphaya, Tanaporn; Weerachayaphorn, Jittima; Songserm, Thaweesak; Saengsirisuwan, Vitoon

    2017-08-01

    The role of gender in the progression of fatty liver due to chronic high-fat high-fructose diet (HFFD) has not been studied. The present investigation assessed whether HFFD induced hepatic perturbations differently between the sexes and examined the potential mechanisms. Male, female, and ovariectomized (OVX) Sprague-Dawley rats were fed either a control diet or HFFD for 12 wk. Indexes of liver damage and hepatic steatosis were analyzed biochemically and histologically together with monitoring changes in hepatic gene and protein expression. HFFD induced a higher degree of hepatic steatosis in females, with significant increases in proteins involved in hepatic lipogenesis, whereas HFFD significantly induced liver injury, inflammation, and oxidative stress only in males. Interestingly, a significant increase in hepatic fibroblast growth factor 21 (FGF21) protein expression was observed in HFFD-fed males but not in HFFD-fed females. Ovarian hormone deprivation by itself led to a significant reduction in FGF21 with hepatic steatosis, and HFFD further aggravated hepatic fat accumulation in OVX rats. Importantly, estrogen replacement restored hepatic FGF21 levels and reduced hepatic steatosis in HFFD-fed OVX rats. Collectively, our results indicate that male rats are more susceptible to HFFD-induced hepatic inflammation and that the mechanism underlying this sex dimorphism is mediated through hepatic FGF21 expression. Our findings reveal sex differences in the development of HFFD-induced fatty liver and indicate the protective role of estrogen against HFFD-induced hepatic steatosis. Copyright © 2017 the American Physiological Society.

  15. Interferon-Mediated Innate Immune Responses against Malaria Parasite Liver Stages

    Directory of Open Access Journals (Sweden)

    Jessica L. Miller

    2014-04-01

    Full Text Available Mosquito-transmitted malaria parasites infect hepatocytes and asymptomatically replicate as liver stages. Using RNA sequencing, we show that a rodent malaria liver-stage infection stimulates a robust innate immune response including type I interferon (IFN and IFNγ pathways. Liver-stage infection is suppressed by these infection-engendered innate responses. This suppression was abrogated in mice deficient in IFNγ, the type I IFN α/β receptor (IFNAR, and interferon regulatory factor 3. Natural killer and CD49b+CD3+ natural killer T (NKT cells increased in the liver after a primary infection, and CD1d-restricted NKT cells, which secrete IFNγ, were critical in reducing liver-stage burden of a secondary infection. Lack of IFNAR signaling abrogated the increase in NKT cell numbers in the liver, showing a link between type I IFN signaling, cell recruitment, and subsequent parasite elimination. Our findings demonstrate innate immune sensing of malaria parasite liver-stage infection and that the ensuing innate responses can eliminate the parasite.

  16. The antiviral drug tenofovir, an inhibitor of Pannexin-1-mediated ATP release, prevents liver and skin fibrosis by downregulating adenosine levels in the liver and skin.

    Directory of Open Access Journals (Sweden)

    Jessica L Feig

    Full Text Available Fibrosing diseases are a leading cause of morbidity and mortality worldwide and, therefore, there is a need for safe and effective antifibrotic therapies. Adenosine, generated extracellularly by the dephosphorylation of adenine nucleotides, ligates specific receptors which play a critical role in development of hepatic and dermal fibrosis. Results of recent clinical trials indicate that tenofovir, a widely used antiviral agent, reverses hepatic fibrosis/cirrhosis in patients with chronic hepatitis B infection. Belonging to the class of acyclic nucleoside phosphonates, tenofovir is an analogue of AMP. We tested the hypothesis that tenofovir has direct antifibrotic effects in vivo by interfering with adenosine pathways of fibrosis using two distinct models of adenosine and A2AR-mediated fibrosis.Thioacetamide (100mg/kg IP-treated mice were treated with vehicle, or tenofovir (75mg/kg, SubQ (n = 5-10. Bleomycin (0.25U, SubQ-treated mice were treated with vehicle or tenofovir (75mg/kg, IP (n = 5-10. Adenosine levels were determined by HPLC, and ATP release was quantitated as luciferase-dependent bioluminescence. Skin breaking strength was analysed and H&E and picrosirus red-stained slides were imaged. Pannexin-1expression was knocked down following retroviral-mediated expression of of Pannexin-1-specific or scrambled siRNA.Treatment of mice with tenofovir diminished adenosine release from the skin of bleomycin-treated mice and the liver of thioacetamide-treated mice, models of diffuse skin fibrosis and hepatic cirrhosis, respectively. More importantly, tenofovir treatment diminished skin and liver fibrosis in these models. Tenofovir diminished extracellular adenosine concentrations by inhibiting, in a dose-dependent fashion, cellular ATP release but not in cells lacking Pannexin-1.These studies suggest that tenofovir, a widely used antiviral agent, could be useful in the treatment of fibrosing diseases.

  17. FGF21 Mediates Endocrine Control of Simple Sugar Intake and Sweet Taste Preference by the Liver

    DEFF Research Database (Denmark)

    von Holstein-Rathlou, Stephanie; BonDurant, Lucas D; Peltekian, Lila

    2016-01-01

    The liver is an important integrator of nutrient metabolism, yet no liver-derived factors regulating nutrient preference or carbohydrate appetite have been identified. Here we show that the liver regulates carbohydrate intake through production of the hepatokine fibroblast growth factor 21 (FGF21......), which markedly suppresses consumption of simple sugars, but not complex carbohydrates, proteins, or lipids. Genetic loss of FGF21 in mice increases sucrose consumption, whereas acute administration or overexpression of FGF21 suppresses the intake of both sugar and non-caloric sweeteners. FGF21 does...... not affect chorda tympani nerve responses to sweet tastants, instead reducing sweet-seeking behavior and meal size via neurons in the hypothalamus. This liver-to-brain hormonal axis likely represents a negative feedback loop as hepatic FGF21 production is elevated by sucrose ingestion. We conclude...

  18. SREBP-1c overactivates ROS-mediated hepatic NF-κB inflammatory pathway in dairy cows with fatty liver.

    Science.gov (United States)

    Li, Xinwei; Huang, Weikun; Gu, Jingmin; Du, Xiliang; Lei, Lin; Yuan, Xue; Sun, Guoquan; Wang, Zhe; Li, Xiaobing; Liu, Guowen

    2015-10-01

    Dairy cows with fatty liver are characterized by hepatic lipid accumulation and a severe inflammatory response. Sterol receptor element binding protein-1c (SREBP-1c) and nuclear factor κB (NF-κB) are components of the main pathways for controlling triglyceride (TG) accumulation and inflammatory levels, respectively. A previous study demonstrated that hepatic inflammatory levels are positively correlated with hepatic TG content. We therefore speculated that SREBP-1c might play an important role in the overactivation of the hepatic NF-κB inflammatory pathway in cows with fatty liver. Compared with healthy cows, cows with fatty liver exhibited severe hepatic injury and high blood concentrations of the inflammatory cytokines TNF-α, IL-6 and IL-1β. Hepatic SREBP-1c-mediated lipid synthesis and the NF-κB inflammatory pathway were both overinduced in cows with fatty liver. In vitro, treatment with non-esterified fatty acids (NEFA) further increased SREBP-1c expression and NF-κB pathway activation, which then promoted TG and inflammatory cytokine synthesis. SREBP-1c overexpression overactivated the NF-κB inflammatory pathway in hepatocytes by increasing ROS content and not through TLR4. Furthermore, SREBP-1c silencing decreased ROS content and further attenuated the activation of the NEFA-induced NF-κB pathway, thereby decreasing TNF-α, IL-6 and IL-1β synthesis. SREBP-1c-overexpressing mice exhibited hepatic steatosis and an overinduced hepatic NF-κB pathway. Taken together, these results indicate that SREBP-1c enhances the NEFA-induced overactivation of the NF-κB inflammatory pathway by increasing ROS in cow hepatocytes, thereby further increasing hepatic inflammatory injury in cows with fatty liver. Copyright © 2015. Published by Elsevier Inc.

  19. Cryogenic regenerators

    International Nuclear Information System (INIS)

    Kush, P.; Joshi, S.C.; Thirumaleshwar, M.

    1986-01-01

    Importance of regenerators in cryogenic refrigerators is highlighted. Design aspects of regenerator are reviewed and the factors involved in the selection of regenerator material are enumerated. Various methods used to calculate the heat transfer coefficient and regenerator effectiveness are mentioned. Variation of effectiveness with various parameters is calculated by a computer programme using the ideal, Ackermann and Tipler formulae. Results are presented in graphical form. Listing of the computer programme is given in the Appendix. (author)

  20. Bone morphogenetic protein 9 as a key regulator of liver progenitor cells in DDC-induced cholestatic liver injury.

    Science.gov (United States)

    Addante, Annalisa; Roncero, Cesáreo; Almalé, Laura; Lazcanoiturburu, Nerea; García-Álvaro, María; Fernández, Margarita; Sanz, Julián; Hammad, Seddik; Nwosu, Zeribe C; Lee, Se-Jin; Fabregat, Isabel; Dooley, Steven; Ten Dijke, Peter; Herrera, Blanca; Sánchez, Aránzazu

    2018-05-11

    Bone morphogenetic protein 9 (BMP9) interferes with liver regeneration upon acute injury, while promoting fibrosis upon carbon tetrachloride-induced chronic injury. We have now addressed the role of BMP9 in 3,5 diethoxicarbonyl-1,4 dihydrocollidine (DDC)-induced cholestatic liver injury, a model of liver regeneration mediated by hepatic progenitor cell (known as oval cell), exemplified as ductular reaction and oval cell expansion. WT and BMP9KO mice were submitted to DDC diet. Livers were examined for liver injury, fibrosis, inflammation and oval cell expansion by serum biochemistry, histology, RT-qPCR and western blot. BMP9 signalling and effects in oval cells were studied in vitro using western blot and transcriptional assays, plus functional assays of DNA synthesis, cell viability and apoptosis. Crosslinking assays and short hairpin RNA approaches were used to identify the receptors mediating BMP9 effects. Deletion of BMP9 reduces liver damage and fibrosis, but enhances inflammation upon DDC feeding. Molecularly, absence of BMP9 results in overactivation of PI3K/AKT, ERK-MAPKs and c-Met signalling pathways, which together with an enhanced ductular reaction and oval cell expansion evidence an improved regenerative response and decreased damage in response to DDC feeding. Importantly, BMP9 directly targets oval cells, it activates SMAD1,5,8, decreases cell growth and promotes apoptosis, effects that are mediated by Activin Receptor-Like Kinase 2 (ALK2) type I receptor. We identify BMP9 as a negative regulator of oval cell expansion in cholestatic injury, its deletion enhancing liver regeneration. Likewise, our work further supports BMP9 as an attractive therapeutic target for chronic liver diseases. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Liver Immunology

    Science.gov (United States)

    Bogdanos, Dimitrios P.; Gao, Bin; Gershwin, M. Eric

    2014-01-01

    The liver is the largest organ in the body and is generally regarded by non-immunologists as not having lymphoid function. However, such is far from accurate. This review highlights the importance of the liver as a lymphoid organ. Firstly, we discuss experimental data surrounding the role of liver as a lymphoid organ. The liver facilitates a tolerance rather than immunoreactivity, which protects the host from antigenic overload of dietary components and drugs derived from the gut and is also instrumental to fetal immune tolerance. Loss of liver tolerance leads to autoaggressive phenomena which if are not controlled by regulatory lymphoid populations may lead to the induction of autoimmune liver diseases. Liver-related lymphoid subpopulations also act as critical antigen-presenting cells. The study of the immunological properties of liver and delineation of the microenvironment of the intrahepatic milieu in normal and diseased livers provides a platform to understand the hierarchy of a series of detrimental events which lead to immune-mediated destruction of the liver and the rejection of liver allografts. The majority of emphasis within this review will be on the normal mononuclear cell composition of the liver. However, within this context, we will discus select, but not all, immune mediated liver disease and attempt to place these data in the context of human autoimmunity. PMID:23720323

  2. MicroRNA-mediated suppression of oncolytic adenovirus replication in human liver.

    Directory of Open Access Journals (Sweden)

    Erkko Ylösmäki

    Full Text Available MicroRNAs (miRNAs are important and ubiquitous regulators of gene expression that can suppress their target genes by translational inhibition as well as mRNA destruction. Cell type-specific miRNA expression patterns have been successfully exploited for targeting the expression of experimental and therapeutic gene constructs, for example to reduce pathogenic effects of cancer virotherapy in normal tissues. In order to avoid liver damage associated with systemic or intrahepatic delivery of oncolytic adenoviruses we have introduced the concept of suppressing adenovirus replication in hepatic cells by inserting target elements for the liver-specific miR122 into the viral genome. Here we show using ex vivo cultured tissue specimens that six perfectly complementary miR122 target sites in the 3' untranslated region of the viral E1A gene are sufficient in the absence of any other genetic modifications to prevent productive replication of serotype 5 adenovirus (Ad5 in normal human liver. This modification did not compromise the replicative capacity of the modified virus in cancer tissue derived from a colon carcinoma liver metastasis or its oncolytic potency in a human lung cancer xenograft mouse model. Unlike wild-type Ad5, the modified virus did not result in increased serum levels of liver enzymes in infected mice. These results provide a strong preclinical proof of concept for the use of miR122 target sites for reducing the risk of liver damage caused by oncolytic adenoviruses, and suggest that ectopic miR122 target elements should be considered as an additional safety measure included in any therapeutic virus or viral vector posing potential hazard to the liver.

  3. Tendon tissue engineering: adipose-derived stem cell and GDF-5 mediated regeneration using electrospun matrix systems

    International Nuclear Information System (INIS)

    James, R; Kumbar, S G; Laurencin, C T; Balian, G; Chhabra, A B

    2011-01-01

    Tendon tissue engineering with a biomaterial scaffold that mimics the tendon extracellular matrix (ECM) and is biomechanically suitable, and when combined with readily available autologous cells, may provide successful regeneration of defects in tendon. Current repair strategies using suitable autografts and freeze-dried allografts lead to a slow repair process that is sub-optimal and fails to restore function, particularly in difficult clinical situations such as zone II flexor tendon injuries of the hand. We have investigated the effect of GDF-5 on cell proliferation and gene expression by primary rat adipose-derived stem cells (ADSCs) that were cultured on a poly(dl-lactide-co-glycolide) PLAGA fiber scaffold and compared to a PLAGA 2D film scaffold. The electrospun scaffold mimics the collagen fiber bundles present in native tendon tissue, and supports the adhesion and proliferation of multipotent ADSCs. Gene expression of scleraxis, the neotendon marker, was upregulated seven- to eightfold at 1 week with GDF-5 treatment when cultured on a 3D electrospun scaffold, and was significantly higher at 2 weeks compared to 2D films with or without GDF-5 treatment. Expression of the genes that encode the major tendon ECM protein, collagen type I, was increased by fourfold starting at 1 week on treatment with 100 ng mL -1 GDF-5, and at all time points the expression was significantly higher compared to 2D films irrespective of GDF-5 treatment. Thus stimulation with GDF-5 can modulate primary ADSCs on a PLAGA fiber scaffold to produce a soft, collagenous musculoskeletal tissue that fulfills the need for tendon regeneration.

  4. Tendon tissue engineering: adipose-derived stem cell and GDF-5 mediated regeneration using electrospun matrix systems.

    Science.gov (United States)

    James, R; Kumbar, S G; Laurencin, C T; Balian, G; Chhabra, A B

    2011-04-01

    Tendon tissue engineering with a biomaterial scaffold that mimics the tendon extracellular matrix (ECM) and is biomechanically suitable, and when combined with readily available autologous cells, may provide successful regeneration of defects in tendon. Current repair strategies using suitable autografts and freeze-dried allografts lead to a slow repair process that is sub-optimal and fails to restore function, particularly in difficult clinical situations such as zone II flexor tendon injuries of the hand. We have investigated the effect of GDF-5 on cell proliferation and gene expression by primary rat adipose-derived stem cells (ADSCs) that were cultured on a poly(DL-lactide-co-glycolide) PLAGA fiber scaffold and compared to a PLAGA 2D film scaffold. The electrospun scaffold mimics the collagen fiber bundles present in native tendon tissue, and supports the adhesion and proliferation of multipotent ADSCs. Gene expression of scleraxis, the neotendon marker, was upregulated seven- to eightfold at 1 week with GDF-5 treatment when cultured on a 3D electrospun scaffold, and was significantly higher at 2 weeks compared to 2D films with or without GDF-5 treatment. Expression of the genes that encode the major tendon ECM protein, collagen type I, was increased by fourfold starting at 1 week on treatment with 100 ng mL(-1) GDF-5, and at all time points the expression was significantly higher compared to 2D films irrespective of GDF-5 treatment. Thus stimulation with GDF-5 can modulate primary ADSCs on a PLAGA fiber scaffold to produce a soft, collagenous musculoskeletal tissue that fulfills the need for tendon regeneration.

  5. Tendon tissue engineering: Adipose 1 derived stem cell and GDF-5 mediated regeneration using electrospun matrix systems

    Science.gov (United States)

    James, R; Kumbar, S G; Laurencin, C T; Balian, G; Chhabra, A B

    2011-01-01

    Tendon tissue engineering with a biomaterial scaffold that mimics the tendon extracellular matrix (ECM) and is biomechanically suitable when combined with readily available autologous cells may provide successful regeneration of defects in tendon. Current repair strategies using suitable autografts and freeze-dried allografts lead to a slow repair process that is sub-optimal and fails to restore function, particularly in difficult clinical situations such as zone II flexor tendon injuries of the hand. We have investigated the effect of GDF-5 on cell proliferation and gene expression by primary rat adipose-derived stromal cells (ADSCs) that were cultured on poly(DL-lactide-co-glycolide) PLAGA fiber scaffold and compared to PLAGA 2D film scaffold. The electrospun scaffold mimics the collagen fiber bundles present in native tendon tissue, and supports the adhesion and proliferation of multipotent ADSCs. Gene expression of scleraxis, the neotendon marker was upregulated 7 – 8 fold at 1 week with GDF-5 treatment when cultured on 3D electrospun scaffold, and was significantly higher at 2 weeks compared to 2D films with or without GDF-5 treatment. Expression of the genes that encode the major tendon ECM protein, collagen type I, was increased by 4 fold starting at 1 week on treatment with 100ng/mL GDF-5, and at all time points the expression was significantly higher compared to 2D films irrespective of GDF-5 treatment. Thus stimulation with GDF-5 can modulate primary ADSCs on PLAGA fiber scaffold to produce a soft, collagenous musculoskeletal tissue that fulfills the need for tendon regeneration. PMID:21436509

  6. Tendon tissue engineering: adipose-derived stem cell and GDF-5 mediated regeneration using electrospun matrix systems

    Energy Technology Data Exchange (ETDEWEB)

    James, R [Department of Biomedical Engineering, University of Virginia, Charlottesville, VA 22908 (United States); Kumbar, S G; Laurencin, C T [Department of Orthopaedic Surgery, University of Connecticut Health Center, Farmington, CT 06030 (United States); Balian, G; Chhabra, A B, E-mail: ac2h@hscmail.mcc.virginia.edu [Department of Orthopaedic Surgery, University of Virginia, Charlottesville, VA 22908 (United States)

    2011-04-15

    Tendon tissue engineering with a biomaterial scaffold that mimics the tendon extracellular matrix (ECM) and is biomechanically suitable, and when combined with readily available autologous cells, may provide successful regeneration of defects in tendon. Current repair strategies using suitable autografts and freeze-dried allografts lead to a slow repair process that is sub-optimal and fails to restore function, particularly in difficult clinical situations such as zone II flexor tendon injuries of the hand. We have investigated the effect of GDF-5 on cell proliferation and gene expression by primary rat adipose-derived stem cells (ADSCs) that were cultured on a poly(dl-lactide-co-glycolide) PLAGA fiber scaffold and compared to a PLAGA 2D film scaffold. The electrospun scaffold mimics the collagen fiber bundles present in native tendon tissue, and supports the adhesion and proliferation of multipotent ADSCs. Gene expression of scleraxis, the neotendon marker, was upregulated seven- to eightfold at 1 week with GDF-5 treatment when cultured on a 3D electrospun scaffold, and was significantly higher at 2 weeks compared to 2D films with or without GDF-5 treatment. Expression of the genes that encode the major tendon ECM protein, collagen type I, was increased by fourfold starting at 1 week on treatment with 100 ng mL{sup -1} GDF-5, and at all time points the expression was significantly higher compared to 2D films irrespective of GDF-5 treatment. Thus stimulation with GDF-5 can modulate primary ADSCs on a PLAGA fiber scaffold to produce a soft, collagenous musculoskeletal tissue that fulfills the need for tendon regeneration.

  7. Arg354 in the catalytic centre of bovine liver catalase is protected from methylglyoxal-mediated glycation.

    Science.gov (United States)

    Scheckhuber, Christian Q

    2015-12-30

    In addition to controlled post-translational modifications proteins can be modified with highly reactive compounds. Usually this leads to a compromised functionality of the protein. Methylglyoxal is one of the most common agents that attack arginine residues. Methylglyoxal is also regarded as a pro-oxidant that affects cellular redox homeostasis by contributing to the formation of reactive oxygen species. Antioxidant enzymes like catalase are required to protect the cell from oxidative damage. These enzymes are also targets for methylglyoxal-mediated modification which could severely affect their catalytic activity in breaking down reactive oxygen species to less reactive or inert compounds. Here, bovine liver catalase was incubated with high levels of methylglyoxal to induce its glycation. This treatment did not lead to a pronounced reduction of enzymatic activity. Subsequently methylglyoxal-mediated arginine modifications (hydroimidazolone and dihydroxyimidazolidine) were quantitatively analysed by sensitive nano high performance liquid chromatography/electron spray ionisation/tandem mass spectrometry. Whereas several arginine residues displayed low to moderate levels of glycation (e.g., Arg93, Arg365, Arg444) Arg354 in the active centre of catalase was never found to be modified. Bovine liver catalase is able to tolerate very high levels of the modifying α-oxoaldehyde methylglyoxal so that its essential enzymatic function is not impaired.

  8. MicroRNA-mediated regulation of glutathione and methionine metabolism and its relevance for liver disease.

    Science.gov (United States)

    Lu, Shelly C; Mato, José M; Espinosa-Diez, Cristina; Lamas, Santiago

    2016-11-01

    The discovery of the microRNA (miRNA) family of small RNAs as fundamental regulators of post-transcriptional gene expression has fostered research on their importance in every area of biology and clinical medicine. In the particular area of liver metabolism and disease, miRNAs are gaining increasing importance. By focusing on two fundamental hepatic biosynthetic pathways, glutathione and methionine, we review recent advances on the comprehension of the role of miRNAs in liver pathophysiology and more specifically of models of hepatic cholestasis/fibrosis and hepatocellular carcinoma. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Human parvovirus B19 VP1u Protein as inflammatory mediators induces liver injury in naïve mice.

    Science.gov (United States)

    Hsu, Tsai-Ching; Chiu, Chun-Ching; Chang, Shun-Chih; Chan, Hsu-Chin; Shi, Ya-Fang; Chen, Tzy-Yen; Tzang, Bor-Show

    2016-01-01

    Human parvovirus B19 (B19V) is a human pathogen known to be associated with many non-erythroid diseases, including hepatitis. Although B19V VP1-unique region (B19-VP1u) has crucial roles in the pathogenesis of B19V infection, the influence of B19-VP1u proteins on hepatic injury is still obscure. This study investigated the effect and possible inflammatory signaling of B19-VP1u in livers from BALB/c mice that were subcutaneously inoculated with VP1u-expressing COS-7 cells. The in vivo effects of B19-VP1u were analyzed by using live animal imaging system (IVIS), Haematoxylin-Eosin staining, gel zymography, and immunoblotting after inoculation. Markedly hepatocyte disarray and lymphocyte infiltration, enhanced matrix metalloproteinase (MMP)-9 activity and increased phosphorylation of p38, ERK, IKK-α, IκB and NF-κB (p-p65) proteins were observed in livers from BALB/c mice receiving COS-7 cells expressing B19-VP1u as well as the significantly increased CRP, IL-1β and IL-6. Notably, IFN-γ and phosphorylated STAT1, but not STAT3, were also significantly increased in the livers of BALB/c mice that were subcutaneously inoculated with VP1u-expressing COS-7 cells. These findings revealed the effects of B19-VP1u on liver injury and suggested that B19-VP1u may have a role as mediators of inflammation in B19V infection.

  10. Interleukin-15-mediated inflammation promotes non-alcoholic fatty liver disease

    NARCIS (Netherlands)

    Cepero-Donates, Yuneivy; Lacraz, Grégory; Ghobadi, Farnaz; Rakotoarivelo, Volatiana; Orkhis, Sakina; Mayhue, Marian; Chen, Yi Guang; Rola-Pleszczynski, Marek; Menendez, Alfredo; Ilangumaran, Subburaj; Ramanathan, Sheela

    2016-01-01

    Interleukin-15 (IL-15) is essential for the homeostasis of lymphoid cells particularly memory CD8+ T cells and NK cells. These cells are abundant in the liver, and are implicated in obesity-associated pathogenic processes. Here we characterized obesity-associated metabolic and cellular changes in

  11. MicroRNA-mediated Th2 bias in methimazole-induced acute liver injury in mice

    International Nuclear Information System (INIS)

    Uematsu, Yasuaki; Akai, Sho; Tochitani, Tomoaki; Oda, Shingo; Yamada, Toru; Yokoi, Tsuyoshi

    2016-01-01

    MicroRNA (miRNA) is a class of small non-coding RNAs containing approximately 20 nucleotides that negatively regulate target gene expression. Little is known about the role of individual miRNAs and their targets in immune- and inflammation-related responses in drug-induced liver injury. In the present study, involvement of miRNAs in the T helper (Th) 2-type immune response was investigated using a methimazole (MTZ)-induced liver injury mouse model. Co-administration of L-buthionine-S,R-sulfoximine and MTZ induced acute hepatocellular necrosis and elevated plasma levels of alanine aminotransferase (ALT) from 4 h onward in female Balb/c mice. The hepatic mRNA expression of Th2 promotive factors was significantly increased concomitantly with plasma ALT levels. In contrast, the hepatic mRNA expression of Th2 suppressive factors was significantly decreased during the early phase of liver injury. Comprehensive profiling of hepatic miRNA expression was analyzed before the onset of MTZ-induced liver injury. Using in silico prediction of miRNAs that possibly regulate Th2-related genes and subsequent quantification, we identified up-regulation of expression of miR-29b-1-5p and miR-449a-5p. Among targets of these miRNAs, down-regulation of Th2 suppressive transcription factors, such as SRY-related HMG-box 4 (SOX4) and lymphoid enhancer factor-1 (LEF1), were observed from the early phase of liver injury. In conclusion, negative regulation of the expression of SOX4 by miR-29b-1-5p and that of LEF1 by miR-449a-5p is suggested to play an important role in the development of Th2 bias in MTZ-induced liver injury. - Highlights: • Methimazole induced hepatic Th2 bias in the pathogenesis of liver injury in mice. • Rapid down-regulation of SOX4 and LEF1 may initiate and/or maintain hepatic Th2 bias. • Negative regulation of SOX4 by miR-29b-1-5p and LEF1 by miR-449a-5p was suggested.

  12. MicroRNA-mediated Th2 bias in methimazole-induced acute liver injury in mice

    Energy Technology Data Exchange (ETDEWEB)

    Uematsu, Yasuaki, E-mail: yasuaki-uematsu@ds-pharma.co.jp [Department of Drug Safety Sciences, Division of Clinical Pharmacology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan); Preclinical Research Laboratories, Sumitomo Dainippon Pharma Co., Ltd., 1-98 Kasugade-naka, 3-chome, Konohana-ku, Osaka (Japan); Akai, Sho [Department of Drug Safety Sciences, Division of Clinical Pharmacology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan); Tochitani, Tomoaki [Preclinical Research Laboratories, Sumitomo Dainippon Pharma Co., Ltd., 1-98 Kasugade-naka, 3-chome, Konohana-ku, Osaka (Japan); Oda, Shingo [Department of Drug Safety Sciences, Division of Clinical Pharmacology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan); Yamada, Toru [Preclinical Research Laboratories, Sumitomo Dainippon Pharma Co., Ltd., 1-98 Kasugade-naka, 3-chome, Konohana-ku, Osaka (Japan); Yokoi, Tsuyoshi [Department of Drug Safety Sciences, Division of Clinical Pharmacology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan)

    2016-09-15

    MicroRNA (miRNA) is a class of small non-coding RNAs containing approximately 20 nucleotides that negatively regulate target gene expression. Little is known about the role of individual miRNAs and their targets in immune- and inflammation-related responses in drug-induced liver injury. In the present study, involvement of miRNAs in the T helper (Th) 2-type immune response was investigated using a methimazole (MTZ)-induced liver injury mouse model. Co-administration of L-buthionine-S,R-sulfoximine and MTZ induced acute hepatocellular necrosis and elevated plasma levels of alanine aminotransferase (ALT) from 4 h onward in female Balb/c mice. The hepatic mRNA expression of Th2 promotive factors was significantly increased concomitantly with plasma ALT levels. In contrast, the hepatic mRNA expression of Th2 suppressive factors was significantly decreased during the early phase of liver injury. Comprehensive profiling of hepatic miRNA expression was analyzed before the onset of MTZ-induced liver injury. Using in silico prediction of miRNAs that possibly regulate Th2-related genes and subsequent quantification, we identified up-regulation of expression of miR-29b-1-5p and miR-449a-5p. Among targets of these miRNAs, down-regulation of Th2 suppressive transcription factors, such as SRY-related HMG-box 4 (SOX4) and lymphoid enhancer factor-1 (LEF1), were observed from the early phase of liver injury. In conclusion, negative regulation of the expression of SOX4 by miR-29b-1-5p and that of LEF1 by miR-449a-5p is suggested to play an important role in the development of Th2 bias in MTZ-induced liver injury. - Highlights: • Methimazole induced hepatic Th2 bias in the pathogenesis of liver injury in mice. • Rapid down-regulation of SOX4 and LEF1 may initiate and/or maintain hepatic Th2 bias. • Negative regulation of SOX4 by miR-29b-1-5p and LEF1 by miR-449a-5p was suggested.

  13. MET Signaling Mediates Intestinal Crypt-Villus Development, Regeneration, and Adenoma Formation and Is Promoted by Stem Cell CD44 Isoforms.

    Science.gov (United States)

    Joosten, Sander P J; Zeilstra, Jurrit; van Andel, Harmen; Mijnals, R Clinton; Zaunbrecher, Joost; Duivenvoorden, Annet A M; van de Wetering, Marc; Clevers, Hans; Spaargaren, Marcel; Pals, Steven T

    2017-10-01

    /Met fl/fl /LacZ mice. Lgr5 Creert2 /Met fl/fl /LacZ mice had impaired regeneration of MET-deficient ISCs. Adenoma organoids stimulated with EGF or HGF expanded to almost twice the size of nonstimulated organoids. MET-deficient adenoma organoids did not respond to HGF stimulation, but did respond to EGF. ISC-specific disruption of Met (Lgr5 Creert2 /Met fl/fl /Apc fl/fl mice) caused a twofold increase in apoptosis in microadenomas, resulting in an approximately 50% reduction of microadenoma numbers and significantly reduced average adenoma size. Total epithelial disruption of Met (Ah Cre /Met fl/fl /Apc fl/+ mice) resulted in an approximate 50% reduction in (micro)adenoma numbers. Intestinal crypts from Cd44 -/- mice did not expand to the same extent as crypts from Cd44 +/+ mice on stimulation with HGF, but had the same response to EGF. The negative effect on HGF-mediated growth was overcome by expression of CD44v4-10, but not by CD44s. Similarly, HGF-mediated expansion of adenoma organoids required CD44v4-10. In studies of intestinal organoid cultures and mice with inducible deletion of MET, we found HGF receptor signaling to regulate intestinal homeostasis and regeneration, as well as adenoma formation. These activities of MET are promoted by the stem cell CD44 isoform CD44v4-10. Our findings provide rationale for targeting signaling via MET and CD44 during anti-EGF receptor therapy of patients with colorectal cancer or in patients resistant to EGF receptor inhibitors. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

  14. PEPCK-M expression in mouse liver potentiates, not replaces, PEPCK-C mediated gluconeogenesis

    Science.gov (United States)

    Méndez-Lucas, Andrés; Duarte, João; Sunny, Nishanth E.; Satapati, Santhosh; He, TianTeng; Fu, Xiaorong; Bermúdez, Jordi; Burgess, Shawn C.; Perales, Jose C.

    2013-01-01

    Background & Aims Hepatic gluconeogenesis helps maintain systemic energy homeostasis by compensating for discontinuities in nutrient supply. Liver specific deletion of cytosolic phosphoenolpyruvate carboxykinase (PEPCK-C) abolishes gluconeogenesis from mitochondrial substrates, deregulates lipid metabolism and affects TCA cycle. While, mouse liver almost exclusively expresses PEPCK-C, humans equally present a mitochondrial isozyme (PEPCK-M). Despite clear relevance to human physiology, the role of PEPCK-M and its gluconeogenic potential remain unknown. Here, we test the significance of PEPCK-M in gluconeogenesis and TCA cycle function in liver-specific PEPCK-C knockout and WT mice. Methods The effects of the overexpression of PEPCK-M were examined by a combination of tracer studies and molecular biology techniques. Partial PEPCK-C re-expression was used as a positive control. Metabolic fluxes were evaluated in isolated livers by NMR using 2H and 13C tracers. Gluconeogenic potential, together with metabolic profiling, were investigated in vivo and in primary hepatocytes. Results PEPCK-M expression partially rescued defects in lipid metabolism, gluconeogenesis and TCA cycle function impaired by PEPCK-C deletion, while ~10% re-expression of PEPCK-C normalized most parameters. When PEPCK-M was expressed in the presence of PEPCK-C, the mitochondrial isozyme amplified total gluconeogenic capacity, suggesting autonomous regulation of oxaloacetate to phosphoenolpyruvate fluxes by the individual isoforms. Conclusions We conclude that PEPCK-M has gluconeogenic potential per se, and cooperates with PEPCK-C to adjust gluconeogenic/TCA flux to changes in substrate or energy availability, hinting at a role in the regulation of glucose and lipid metabolism in human liver. PMID:23466304

  15. Experimental data suggesting that inflammation mediated rat liver mitochondrial dysfunction results from secondary hypoxia rather than from direct effects of inflammatory mediators

    Directory of Open Access Journals (Sweden)

    Adelheid eWeidinger

    2013-06-01

    Full Text Available Systemic inflammatory response (SIR comprises direct effects of inflammatory mediators (IM and indirect effects, such as secondary circulatory failure which results in tissue hypoxia (HOX. These two key components, SIR and HOX, cause multiple organ failure (MOF. Since HOX and IM occur and interact simultaneously in vivo, it is difficult to clarify their individual pathological impact. To eliminate this interaction, precision cut liver slices (PCLS were used in this study aiming to dissect the effects of HOX and IM on mitochondrial function, integrity of cellular membrane and the expression of genes associated with inflammation. HOX was induced by incubating PCLS or rat liver mitochondria at pO2<1% followed by reoxygenation (HOX/ROX model. Inflammatory injury was stimulated by incubating PCLS with IM (IM model. We found upregulation of inducible nitric oxide synthase (iNOS expression only in the IM model, while heme oxygenase 1 (HO-1 expression was upregulated only in the HOX/ROX model. Elevated expression of interleukin 6 (IL-6 was found in both models reflecting converging pathways regulating the expression of this gene. Both models caused damage to hepatocytes resulting in the release of alanine aminotransferase (ALT. The leakage of aspartate aminotransferase (AST was observed only during the hypoxic phase in the HOX/ROX model. The reoxygenation phase of HOX, but not IM, drastically impaired mitochondrial electron supply via complex I and II. Additional experiments performed with isolated mitochondria showed that free iron, released during HOX, is likely a key prerequisite of mitochondrial dysfunction induced during the reoxygenation phase. Our data suggests that mitochondrial dysfunction, previously observed in in vivo SIR-models is the result of secondary circulatory failure inducing HOX rather than the result of a direct interaction of IM with liver cells.

  16. Nanocomposite hydrogels stabilized by self-assembled multivalent bisphosphonate-magnesium nanoparticles mediate sustained release of magnesium ion and promote in-situ bone regeneration.

    Science.gov (United States)

    Zhang, Kunyu; Lin, Sien; Feng, Qian; Dong, Chaoqun; Yang, Yanhua; Li, Gang; Bian, Liming

    2017-12-01

    Hydrogels are appealing biomaterials for applications in regenerative medicine due to their tunable physical and bioactive properties. Meanwhile, therapeutic metal ions, such as magnesium ion (Mg 2+ ), not only regulate the cellular behaviors but also stimulate local bone formation and healing. However, the effective delivery and tailored release of Mg 2+ remains a challenge, with few reports on hydrogels being used for Mg 2+ delivery. Bisphosphonate exhibits a variety of specific bioactivities and excellent binding affinity to multivalent cations such as Mg 2+ . Herein, we describe a nanocomposite hydrogel based on hyaluronic acid and self-assembled bisphosphonate-magnesium (BP-Mg) nanoparticles. These nanoparticles bearing acrylate groups on the surface not only function as effective multivalent crosslinkers to strengthen the hydrogel network structure, but also promote the mineralization of hydrogels and mediate sustained release of Mg 2+ . The released Mg 2+ ions facilitate stem cell adhesion and spreading on the hydrogel substrates in the absence of cell adhesion ligands, and promote osteogenesis of the seeded hMSCs in vitro. Furthermore, the acellular porous hydrogels alone can support in situ bone regeneration without using exogenous cells and inductive agents, thereby greatly simplifying the approaches of bone regeneration therapy. In this study, we developed a novel bioactive nanocomposite hydrogel based on hyaluronic acid and self-assembled bisphosphonate-magnesium (BP-Mg) nanoparticles. Such hydrogels are stabilized by the multivalent crosslinking domains formed by the aggregation of Ac-BP-Mg NPs, and therefore show enhanced mechanical properties, improved capacity for mineralization, and controlled release kinetics of Mg 2+ . Moreover, the released Mg 2+ can enhance cell adhesion and spreading, and further promote the osteogenic differentiation of hMSCs. Owing to these unique properties, these acellular hydrogels alone can well facilitate the in vivo

  17. Troxerutin protects against 2,2',4,4'-tetrabromodiphenyl ether (BDE-47)-induced liver inflammation by attenuating oxidative stress-mediated NAD⁺-depletion.

    Science.gov (United States)

    Zhang, Zi-Feng; Zhang, Yan-Qiu; Fan, Shao-Hua; Zhuang, Juan; Zheng, Yuan-Lin; Lu, Jun; Wu, Dong-Mei; Shan, Qun; Hu, Bin

    2015-01-01

    Emerging evidence indicates that 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) induces liver injury through enhanced ROS production and lymphocytic infiltration, which may promote a liver inflammatory response. Antioxidants have been reported to attenuate the cellular toxicity associated with polybrominated diphenyl ethers (PBDEs). In this study, we investigated the effect of troxerutin, a trihydroxyethylated derivative of the natural bioflavonoid rutin, on BDE-47-induced liver inflammation and explored the potential mechanisms underlying this effect. Our results showed that NAD(+)-depletion was involved in the oxidative stress-mediated liver injury in a BDE-47 treated mouse model, which was confirmed by Vitamin E treatment. Furthermore, our data revealed that troxerutin effectively alleviated liver inflammation by mitigating oxidative stress-mediated NAD(+)-depletion in BDE-47 treated mice. Consequently, troxerutin remarkably restored SirT1 protein expression and activity in the livers of BDE-47-treated mice. Mechanistically, troxerutin dramatically repressed the nuclear translocation of NF-κB p65 and the acetylation of NF-κB p65 (Lys 310) and Histone H3 (Lys9) to abate the transcription of inflammatory genes in BDE-47-treated mouse livers. These inhibitory effects of troxerutin were markedly blunted by EX527 (SirT1 inhibitor) treatment. This study provides novel mechanistic insights into the toxicity of BDE-47 and indicates that troxerutin might be used in the prevention and therapy of BDE-47-induced hepatotoxicity. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. MicroRNAs as Signaling Mediators and Biomarkers of Drug- and Chemical-Induced Liver Injury

    Directory of Open Access Journals (Sweden)

    Mitchell R. McGill

    2015-05-01

    Full Text Available Drug-induced liver injury (DILI is major problem for both the drug industry and for clinicians. There are two basic categories of DILI: intrinsic and idiosyncratic. The former is the chief cause of acute liver failure in several developed countries, while the latter is the most common reason for post-marketing drug withdrawal and a major reason for failure to approve new drugs in the U.S. Although considerably more progress has been made in the study of intrinsic DILI, our understanding of both forms of drug hepatotoxicity remains incomplete. Recent work involving microRNAs (miRNAs has advanced our knowledge of DILI in two ways: (1 possible roles of miRNAs in the pathophysiological mechanisms of DILI have been identified, and (2 circulating miRNA profiles have shown promise for the detection and diagnosis of DILI in clinical settings. The purpose of this review is to summarize major findings in these two areas of research. Taken together, exciting progress has been made in the study of miRNAs in DILI. Possible mechanisms through which miRNA species contribute to the basic mechanisms of DILI are beginning to emerge, and new miRNA-based biomarkers have the potential to greatly improve diagnosis of liver injury and prediction of patient outcomes.

  19. Sodium 4-phenylbutyrate protects against liver ischemia reperfusion injury by inhibition of endoplasmic reticulum-stress mediated apoptosis.

    Science.gov (United States)

    Vilatoba, Mario; Eckstein, Christopher; Bilbao, Guadalupe; Smyth, Cheryl A; Jenkins, Stacie; Thompson, J Anthony; Eckhoff, Devin E; Contreras, Juan L

    2005-08-01

    Evidence is emerging that the endoplasmic reticulum (ER) participates in initiation of apoptosis induced by the unfolded protein response and by aberrant Ca(++) signaling during cellular stress such as ischemia/reperfusion injury (I/R injury). ER-induced apoptosis involves the activation of caspase-12 and C/EBP homologous protein (CHOP), and the shutdown of translation initiated by phosphorylation of eIF2alpha. Sodium 4-phenylbutyrate (PBA) is a low molecular weight fatty acid that acts as a chemical chaperone reducing the load of mutant or unfolded proteins retained in the ER during cellular stress and also exerting anti-inflammatory activity. It has been used successfully for treatment of urea cycle disorders and sickle cell disease. Thus, we hypothesized that PBA may reduce ER-induced apoptosis triggered by I/R injury to the liver. Groups of male C57BL/6 mice were subjected to warm ischemia (70% of the liver mass, 45 minutes). Serum aspartate aminotransferase was assessed 6 hours after reperfusion; apoptosis was evaluated by enzyme-linked immunosorbent assays of caspase-12 and plasma tumor necrosis factor alpha, Western blot analyses of eIF2alpha, and reverse transcriptase-polymerase chain reaction of CHOP expression. A dose-dependent decrease in aspartate aminotransferase was demonstrated in mice given intraperitoneal PBA (1 hour before and 12 hours after reperfusion), compared with vehicle-treated controls; this effect was associated with reduced pyknosis, parenchymal hemorrhages, and neutrophil infiltrates in PBA-treated mice, compared with controls. In a lethal model of total liver I/R injury, all vehicle-treated controls died within 3 days after reperfusion. In contrast, 50% survival (>30 days) was observed in animals given PBA. The beneficial effects of PBA were associated with a greater than 45% reduction in apoptosis, decreased ER-mediated apoptosis characterized by significant reduction in caspase-12 activation, and reduced levels of both phosphorylated

  20. AAV8 capsid variable regions at the two-fold symmetry axis contribute to high liver transduction by mediating nuclear entry and capsid uncoating

    International Nuclear Information System (INIS)

    Tenney, Rebeca M.; Bell, Christie L.; Wilson, James M.

    2014-01-01

    Adeno-associated virus serotype 8 (AAV8) is a promising vector for liver-directed gene therapy. Although efficient uncoating of viral capsids has been implicated in AAV8's robust liver transduction, much about the biology of AAV8 hepatotropism remains unclear. Our study investigated the structural basis of AAV8 liver transduction efficiency by constructing chimeric vector capsids containing sequences derived from AAV8 and AAV2 – a highly homologous yet poorly hepatotropic serotype. Engineered vectors containing capsid variable regions (VR) VII and IX from AAV8 in an AAV2 backbone mediated near AAV8-like transduction in mouse liver, with higher numbers of chimeric genomes detected in whole liver cells and isolated nuclei. Interestingly, chimeric capsids within liver nuclei also uncoated similarly to AAV8 by 6 weeks after administration, in contrast with AAV2, of which a significantly smaller proportion were uncoated. This study links specific AAV capsid regions to the transduction ability of a clinically relevant AAV serotype. - Highlights: • We construct chimeric vectors to identify determinants of AAV8 liver transduction. • An AAV2-based vector with 17 AAV8 residues exhibited high liver transduction in mice. • This vector also surpassed AAV2 in cell entry, nuclear entry and onset of expression. • Most chimeric vector particles were uncoated at 6 weeks, like AAV8 and unlike AAV2. • Chimera retained heparin binding and was antigenically distinct from AAV2 and AAV8

  1. AAV8 capsid variable regions at the two-fold symmetry axis contribute to high liver transduction by mediating nuclear entry and capsid uncoating

    Energy Technology Data Exchange (ETDEWEB)

    Tenney, Rebeca M.; Bell, Christie L.; Wilson, James M., E-mail: wilsonjm@mail.med.upenn.edu

    2014-04-15

    Adeno-associated virus serotype 8 (AAV8) is a promising vector for liver-directed gene therapy. Although efficient uncoating of viral capsids has been implicated in AAV8's robust liver transduction, much about the biology of AAV8 hepatotropism remains unclear. Our study investigated the structural basis of AAV8 liver transduction efficiency by constructing chimeric vector capsids containing sequences derived from AAV8 and AAV2 – a highly homologous yet poorly hepatotropic serotype. Engineered vectors containing capsid variable regions (VR) VII and IX from AAV8 in an AAV2 backbone mediated near AAV8-like transduction in mouse liver, with higher numbers of chimeric genomes detected in whole liver cells and isolated nuclei. Interestingly, chimeric capsids within liver nuclei also uncoated similarly to AAV8 by 6 weeks after administration, in contrast with AAV2, of which a significantly smaller proportion were uncoated. This study links specific AAV capsid regions to the transduction ability of a clinically relevant AAV serotype. - Highlights: • We construct chimeric vectors to identify determinants of AAV8 liver transduction. • An AAV2-based vector with 17 AAV8 residues exhibited high liver transduction in mice. • This vector also surpassed AAV2 in cell entry, nuclear entry and onset of expression. • Most chimeric vector particles were uncoated at 6 weeks, like AAV8 and unlike AAV2. • Chimera retained heparin binding and was antigenically distinct from AAV2 and AAV8.

  2. Liver diseases and aging : friends or foes?

    NARCIS (Netherlands)

    Sheedfar, Fareeba; Di Biase, Stefano; Koonen, Debby; Vinciguerra, Manlio

    2013-01-01

    The liver is the only internal human organ capable of natural regeneration of lost tissue, as little as 25% of a liver can regenerate into a whole liver. The process of aging predisposes to hepatic functional and structural impairment and metabolic risk. Therefore, understanding how aging could

  3. Troxerutin protects against 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47)-induced liver inflammation by attenuating oxidative stress-mediated NAD+-depletion

    International Nuclear Information System (INIS)

    Zhang, Zi-Feng; Zhang, Yan-qiu; Fan, Shao-Hua; Zhuang, Juan; Zheng, Yuan-Lin; Lu, Jun; Wu, Dong-Mei; Shan, Qun; Hu, Bin

    2015-01-01

    Highlights: • BDE-47 promotes liver inflammation by triggering oxidative stress-induced NAD + depletion. • Troxerutin inhibits BDE-47-induced liver inflammation via its antioxidant properties. • Troxerutin restores NAD + level and consequently abates SirT1 loss. • Troxerutin represses acetylation of NF-κB p65 (K310) and H3K9. • Troxerutin is a candidate for prevention and therapy of BDE-47-induced hepatotoxicity. - Abstract: Emerging evidence indicates that 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) induces liver injury through enhanced ROS production and lymphocytic infiltration, which may promote a liver inflammatory response. Antioxidants have been reported to attenuate the cellular toxicity associated with polybrominated diphenyl ethers (PBDEs). In this study, we investigated the effect of troxerutin, a trihydroxyethylated derivative of the natural bioflavonoid rutin, on BDE-47-induced liver inflammation and explored the potential mechanisms underlying this effect. Our results showed that NAD + -depletion was involved in the oxidative stress-mediated liver injury in a BDE-47 treated mouse model, which was confirmed by Vitamin E treatment. Furthermore, our data revealed that troxerutin effectively alleviated liver inflammation by mitigating oxidative stress-mediated NAD + -depletion in BDE-47 treated mice. Consequently, troxerutin remarkably restored SirT1 protein expression and activity in the livers of BDE-47-treated mice. Mechanistically, troxerutin dramatically repressed the nuclear translocation of NF-κB p65 and the acetylation of NF-κB p65 (Lys 310) and Histone H3 (Lys9) to abate the transcription of inflammatory genes in BDE-47-treated mouse livers. These inhibitory effects of troxerutin were markedly blunted by EX527 (SirT1 inhibitor) treatment. This study provides novel mechanistic insights into the toxicity of BDE-47 and indicates that troxerutin might be used in the prevention and therapy of BDE-47-induced hepatotoxicity

  4. Vegetative regeneration

    Science.gov (United States)

    George A. Schier; John R. Jones; Robert P. Winokur

    1985-01-01

    Aspen is noted for its ability to regenerate vegetatively by adventitious shoots or suckers that arise on its long lateral roots. It also produces sprouts from stumps and root collars; but they are not common. In a survey of regeneration after clearcutting mature aspen in Utah. Baker (1918b) found that 92% of the shoots originated from roots, 7% from root collars, and...

  5. Regulator of G-protein signaling-5 is a marker of hepatic stellate cells and expression mediates response to liver injury.

    Directory of Open Access Journals (Sweden)

    Arya J Bahrami

    Full Text Available Liver fibrosis is mediated by hepatic stellate cells (HSCs, which respond to a variety of cytokine and growth factors to moderate the response to injury and create extracellular matrix at the site of injury. G-protein coupled receptor (GPCR-mediated signaling, via endothelin-1 (ET-1 and angiotensin II (AngII, increases HSC contraction, migration and fibrogenesis. Regulator of G-protein signaling-5 (RGS5, an inhibitor of vasoactive GPCR agonists, functions to control GPCR-mediated contraction and hypertrophy in pericytes and smooth muscle cells (SMCs. Therefore we hypothesized that RGS5 controls GPCR signaling in activated HSCs in the context of liver injury. In this study, we localize RGS5 to the HSCs and demonstrate that Rgs5 expression is regulated during carbon tetrachloride (CCl4-induced acute and chronic liver injury in Rgs5LacZ/LacZ reporter mice. Furthermore, CCl4 treated RGS5-null mice develop increased hepatocyte damage and fibrosis in response to CCl4 and have increased expression of markers of HSC activation. Knockdown of Rgs5 enhances ET-1-mediated signaling in HSCs in vitro. Taken together, we demonstrate that RGS5 is a critical regulator of GPCR signaling in HSCs and regulates HSC activation and fibrogenesis in liver injury.

  6. [Inhibition of glycogen synthase kinase 3b activity regulates Toll-like receptor 4-mediated liver inflammation].

    Science.gov (United States)

    Ren, Feng; Zhang, Hai-yan; Piao, Zheng-fu; Zheng, Su-jun; Chen, Yu; Chen, De-xi; Duan, Zhong-ping

    2012-09-01

    To determine the mechanism underlying the therapeutic activities of glycogen synthase kinase 3b (GSK3b) against hepatic ischemia-reperfusion (H-IR) injury by investigating the inhibitive effects of GSK3b on inflammation mediated by Toll-like receptor 4 (TLR4). C57BL/6 male mice were subjected to 90 min of warm liver cephalad lobe ischemia, followed by reperfusion for various lengths of time. The mice were divided into three groups: the H-IR untreated model (control group), and the H-IR inflammation-induced models that received an intraperitoneal injection of purified lipopolysaccharide (LPS) endotoxin alone (inflammation group) or with pretreatment of the SB216763 GSK3b-specific inhibitor (intervention group). To create a parallel isolated cell system for detailed investigations of macrophages, marrow-derived stem cells were isolated from femurs of the H-IR control group of mice and used to derive primary macrophages. The cells were then divided into the same three groups as the whole mouse system: control, LPS-induced inflammation model, and inflammation model with SB216763 intervention. Differential expressions of inflammation-related proteins and genes were detected by Western blotting and real-time quantitative PCR, respectively. The phosphorylation levels of ERK, JNK and p38 MAPK were induced in liver at 1 h after reperfusion, but then steadily decreased and returned to baseline levels by 4 h after reperfusion. In addition, the phosphorylation levels of ERK and JNK were induced in macrophages at 15 min after LPS stimulation, while the phosphorylation level of p38 MAPK was induced at 1 h; SB216763 pretreatment suppressed the LPS-stimulated ERK, JNK and p38 phosphorylation in macrophages. In the mouse model, GSK3b activity was found to promote the gene expression of anti-inflammatory cytokine IL-10 (control: 0.21 ± 0.08, inflammation: 0.83 ± 0.21, intervention: 1.76 ± 0.67; F = 3.16, P = 0.027) but to significantly inhibit the gene expression of pro

  7. CCAAT/Enhancer Binding Protein-β Is a Transcriptional Regulator of Peroxisome-Proliferator-Activated Receptor-γ Coactivator-1α in the Regenerating Liver

    OpenAIRE

    Wang, Haitao; Peiris, T. Harshani; Mowery, A.; Le Lay, John; Gao, Yan; Greenbaum, Linda E.

    2008-01-01

    The transcriptional coactivator peroxisome-proliferator-activated receptor-γ coactivator-1α (PGC-1α) is induced in the liver in response to fasting and coordinates the activation of targets necessary for increasing energy production for gluconeogenesis and ketogenesis. After partial hepatectomy, the liver must restore its mass while maintaining metabolic homeostasis to ensure survival. Here we report that PGC-1α is rapidly and dramatically induced after hepatectomy, with an amplitude of induc...

  8. Glycine facilitates gamma-glutamylcysteinylethyl ester-mediated increase in liver glutathione level.

    Science.gov (United States)

    Nishida, K; Ohta, Y; Ishiguro, I

    1997-08-27

    gamma-Glutamylcysteinylethyl ester (gamma-GCE) increases reduced glutathione (GSH) levels in GSH-depleted rat hepatocytes. Because glycine, a constituent of GSH, exists at 0.3 to 0.4 mM in rat plasma, we examined the influence of glycine added to the medium on the action of gamma-GCE to increase GSH levels in the rat hepatocytes. Glycine (0.2-0.8 mM) dose-dependently enhanced gamma-GCE-mediated increase in intracellular GSH levels with an increase in intracellular gamma-GCE levels. These results indicate that exogenous glycine facilitates gamma-GCE-mediated increase in intracellular GSH levels in rat hepatocytes possibly by enhancing the uptake of gamma-GCE into the cells.

  9. CD147 promotes liver fibrosis progression via VEGF-A/VEGFR2 signalling-mediated cross-talk between hepatocytes and sinusoidal endothelial cells.

    Science.gov (United States)

    Yan, Zhaoyong; Qu, Kai; Zhang, Jing; Huang, Qichao; Qu, Ping; Xu, Xinsen; Yuan, Peng; Huang, Xiaojun; Shao, Yongping; Liu, Chang; Zhang, Hongxin; Xing, Jinliang

    2015-10-01

    Although previous evidence indicates close involvement of CD147 in the pathogenesis of liver fibrosis, the underlying molecular mechanisms and its therapeutic value remain largely unknown. In the present study, we investigated the biological roles of CD147 in liver fibrosis and assessed its therapeutic value as a target molecule in the CCl4-induced liver fibrosis mouse model. We found that CD147 was highly expressed in both hepatocytes and SECs (sinusoidal endothelial cells) in fibrotic liver tissues. Additionally, it was significantly associated with the fibrosis stage. TGF-β1 (transforming growth factor β1) was found to be mainly responsible for the up-regulation of CD147. Bioinformatic and experimental data suggest a functional link between CD147 expression and VEGF-A (vascular endothelial growth factor A)/VEGR-2 (VEGF receptor 2) signalling-mediated angiogenesis in fibrotic liver tissues. Furthermore, we observed that the CD147-induced activation of the PI3K (phosphoinositide 3-kinase)/Akt signalling pathway promotes the production of VEGF-A in hepatocytes and expression of VEGFR-2 in SECs, which was found to enhance the angiogenic capability of SECs. Finally, our data indicate that blocking of CD147 using an mAb (monoclonal antibody) attenuated liver fibrosis progression via inhibition of VEGF-A/VEGFR-2 signalling and subsequent amelioration of microvascular abnormality in the CCl4-induced mouse model. Our findings suggest a novel functional mechanism that CD147 may promote liver fibrosis progression via inducing the VEGF-A/VEGFR-2 signalling pathway-mediated cross-talk between hepatocytes and SECs. New strategies based on the intervention of CD147 can be expected for prevention of liver fibrosis. © 2015 Authors; published by Portland Press Limited.

  10. Increased Whole-Body and Sustained Liver Cortisol Regeneration by 11β-Hydroxysteroid Dehydrogenase Type 1 in Obese Men With Type 2 Diabetes Provides a Target for Enzyme Inhibition

    Science.gov (United States)

    Stimson, Roland H.; Andrew, Ruth; McAvoy, Norma C.; Tripathi, Dhiraj; Hayes, Peter C.; Walker, Brian R.

    2011-01-01

    OBJECTIVE The cortisol-regenerating enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) amplifies glucocorticoid levels in liver and adipose tissue. 11β-HSD1 inhibitors are being developed to treat type 2 diabetes. In obesity, 11β-HSD1 is increased in adipose tissue but decreased in liver. The benefits of pharmacological inhibition may be reduced if hepatic 11β-HSD1 is similarly decreased in obese patients with type 2 diabetes. To examine this, we quantified in vivo whole-body, splanchnic, and hepatic 11β-HSD1 activity in obese type 2 diabetic subjects. RESEARCH DESIGN AND METHODS Ten obese men with type 2 diabetes and seven normal-weight control subjects were infused with 9,11,12,12-[2H]4cortisol (40%) and cortisol (60%) at 1.74 mg/h. Adrenal cortisol secretion was suppressed with dexamethasone. Samples were obtained from the hepatic vein and an arterialized hand vein at steady state and after oral administration of cortisone (5 mg) to estimate whole-body and liver 11β-HSD1 activity using tracer dilution. RESULTS In obese type 2 diabetic subjects, the appearance rate of 9,12,12-[2H]3cortisol in arterialized blood was increased (35 ± 2 vs. 29 ± 1 nmol/min, P cortisol production was not reduced (29 ± 6 vs. 29 ± 6 nmol/min), and cortisol appearance in the hepatic vein after oral cortisone was unchanged. CONCLUSIONS Whole-body 11β-HSD1 activity is increased in obese men with type 2 diabetes, whereas liver 11β-HSD1 activity is sustained, unlike in euglycemic obesity. This supports the concept that inhibitors of 11β-HSD1 are likely to be most effective in obese type 2 diabetic subjects. PMID:21266326

  11. Increased whole-body and sustained liver cortisol regeneration by 11beta-hydroxysteroid dehydrogenase type 1 in obese men with type 2 diabetes provides a target for enzyme inhibition.

    Science.gov (United States)

    Stimson, Roland H; Andrew, Ruth; McAvoy, Norma C; Tripathi, Dhiraj; Hayes, Peter C; Walker, Brian R

    2011-03-01

    The cortisol-regenerating enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) amplifies glucocorticoid levels in liver and adipose tissue. 11β-HSD1 inhibitors are being developed to treat type 2 diabetes. In obesity, 11β-HSD1 is increased in adipose tissue but decreased in liver. The benefits of pharmacological inhibition may be reduced if hepatic 11β-HSD1 is similarly decreased in obese patients with type 2 diabetes. To examine this, we quantified in vivo whole-body, splanchnic, and hepatic 11β-HSD1 activity in obese type 2 diabetic subjects. Ten obese men with type 2 diabetes and seven normal-weight control subjects were infused with 9,11,12,12-[(2)H](4)cortisol (40%) and cortisol (60%) at 1.74 mg/h. Adrenal cortisol secretion was suppressed with dexamethasone. Samples were obtained from the hepatic vein and an arterialized hand vein at steady state and after oral administration of cortisone (5 mg) to estimate whole-body and liver 11β-HSD1 activity using tracer dilution. In obese type 2 diabetic subjects, the appearance rate of 9,12,12-[(2)H](3)cortisol in arterialized blood was increased (35 ± 2 vs. 29 ± 1 nmol/min, P cortisol production was not reduced (29 ± 6 vs. 29 ± 6 nmol/min), and cortisol appearance in the hepatic vein after oral cortisone was unchanged. Whole-body 11β-HSD1 activity is increased in obese men with type 2 diabetes, whereas liver 11β-HSD1 activity is sustained, unlike in euglycemic obesity. This supports the concept that inhibitors of 11β-HSD1 are likely to be most effective in obese type 2 diabetic subjects.

  12. Exploring BSEP Inhibition-Mediated Toxicity with a Mechanistic Model of Drug-Induced Liver Injury

    Directory of Open Access Journals (Sweden)

    Jeffrey L Woodhead

    2014-11-01

    Full Text Available Inhibition of the bile salt export pump (BSEP has been linked to incidence of drug-induced liver injury (DILI, presumably by the accumulation of toxic bile acids in the liver. We have previously constructed and validated a model of bile acid disposition within DILIsym®, a mechanistic model of DILI. In this paper, we use DILIsym® to simulate the DILI response of the hepatotoxic BSEP inhibitors bosentan and CP-724,714 and the non-hepatotoxic BSEP inhibitor telmisartan in humans in order to explore whether we can predict that hepatotoxic BSEP inhibitors can cause bile acid accumulation to reach toxic levels. We also simulate bosentan in rats in order to illuminate potential reasons behind the lack of toxicity in rats compared to the toxicity observed in humans. DILIsym® predicts that bosentan, but not telmisartan, will cause mild hepatocellular ATP decline and serum ALT elevation in a simulated population of humans. The difference in hepatotoxic potential between bosentan and telmisartan is consistent with clinical observations. However, DILIsym® underpredicts the incidence of bosentan toxicity. DILIsym® also predicts that bosentan will not cause toxicity in a simulated population of rats, and that the difference between the response to bosentan in rats and in humans is primarily due to the less toxic bile acid pool in rats. Our simulations also suggest a potential synergistic role for bile acid accumulation and mitochondrial electron transport chain inhibition in producing the observed toxicity in CP-724,714, and suggest that CP-724,714 metabolites may also play a role in the observed toxicity. Our work also compares the impact of competitive and noncompetitive BSEP inhibition for CP-724,714 and demonstrates that noncompetitive inhibition leads to much greater bile acid accumulation and potential toxicity. Our research demonstrates the potential for mechanistic modeling to contribute to the understanding of how bile acid transport inhibitors

  13. Germ cell regeneration-mediated, enhanced mutagenesis in the ascidian Ciona intestinalis reveals flexible germ cell formation from different somatic cells.

    Science.gov (United States)

    Yoshida, Keita; Hozumi, Akiko; Treen, Nicholas; Sakuma, Tetsushi; Yamamoto, Takashi; Shirae-Kurabayashi, Maki; Sasakura, Yasunori

    2017-03-15

    The ascidian Ciona intestinalis has a high regeneration capacity that enables the regeneration of artificially removed primordial germ cells (PGCs) from somatic cells. We utilized PGC regeneration to establish efficient methods of germ line mutagenesis with transcription activator-like effector nucleases (TALENs). When PGCs were artificially removed from animals in which a TALEN pair was expressed, somatic cells harboring mutations in the target gene were converted into germ cells, this germ cell population exhibited higher mutation rates than animals not subjected to PGC removal. PGC regeneration enables us to use TALEN expression vectors of specific somatic tissues for germ cell mutagenesis. Unexpectedly, cis elements for epidermis, neural tissue and muscle could be used for germ cell mutagenesis, indicating there are multiple sources of regenerated PGCs, suggesting a flexibility of differentiated Ciona somatic cells to regain totipotency. Sperm and eggs of a single hermaphroditic, PGC regenerated animal typically have different mutations, suggesting they arise from different cells. PGCs can be generated from somatic cells even though the maternal PGCs are not removed, suggesting that the PGC regeneration is not solely an artificial event but could have an endogenous function in Ciona. This study provides a technical innovation in the genome-editing methods, including easy establishment of mutant lines. Moreover, this study suggests cellular mechanisms and the potential evolutionary significance of PGC regeneration in Ciona. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Shanxi Aged Vinegar Protects against Alcohol-Induced Liver Injury via Activating Nrf2-Mediated Antioxidant and Inhibiting TLR4-Induced Inflammatory Response

    Directory of Open Access Journals (Sweden)

    Ting Xia

    2018-06-01

    Full Text Available Shanxi aged vinegar (SAV is a typical fermented and antioxidant food, which has various health-promoting effects. This work aimed to explore the effects of SAV on alcohol-induced liver injury. A mice model of alcoholic liver injury was established to illuminate its potential mechanisms. All mice pretreated with SAV and then received an ethanol solution (50% w/v, 4.8 g/kg b.w.. The results showed that SAV ameliorated alcohol-induced histological changes and elevation of liver enzymes. SAV attenuated alcohol-induced oxidative stress by declining levels of hepatic oxidants, and restoring depletion of antioxidant enzyme activities in mice livers. Moreover, SAV alleviated alcohol-induced oxidative damage by activating nuclear factor erythroid-2-related factor 2 (Nrf2-mediated signal pathway. In addition, SAV prevented alcohol-induced inflammation by suppressing lipopolysaccharide (LPS level and activities of pro-inflammatory enzymes, and regulating inflammatory cytokines. SAV inhibited alcohol-induced inflammation through down-regulating the expression of Toll-like receptor 4 (TLR4-mediated inflammatory response. The findings provide crucial evidence for elucidating the hepatoprotective mechanisms of SAV and encourage the future application of SAV as a functional food for liver protection.

  15. Functional characterization of estrogen receptor subtypes, ERα and ERβ, mediating vitellogenin production in the liver of rainbow trout

    International Nuclear Information System (INIS)

    Leanos-Castaneda, Olga; Kraak, Glen van der

    2007-01-01

    The estrogen-dependent process of vitellogenesis is a key function on oviparous fish reproduction and it has been widely used as an indicator of xenoestrogen exposure. The two estrogen receptor (ER) subtypes, ERα and ERβ, are often co-expressed in the liver of fish. The relative contribution of each ER subtype to modulate vitellogenin production by hepatocytes was studied using selected compounds known to preferentially interact with specific ER subtypes: propyl-pyrazole-triol (PPT) an ERα selective agonist, methyl-piperidino-pyrazole (MPP) an ERα selective antagonist, and diarylpropionitrile (DPN) an ERβ selective agonist. First, the relative binding affinity of the test compounds to estradiol for rainbow trout hepatic nuclear ER was determined using a competitive ligand binding assay. All the test ligands achieved complete displacement of specific [ 3 H]-estradiol binding from the nuclear ER extract. This indicates that the test ligands have the potential to modify the ER function in the rainbow trout liver. Secondly, the ability of the test compounds to induce or inhibit vitellogenin production by primary cultures of rainbow trout hepatocytes was studied. Estradiol and DPN were the only compounds that induced a dose-dependent increase on vitellogenin synthesis. The lack of vitellogenin induction by PPT indicates that ERα could not have a role on this reproductive process whereas the ability of DPN to induce vitellogenin production supports the participation of ERβ. In addition, this hypothesis is reinforced by the results obtained from MPP plus estradiol. On one hand, the absence of suppressive activity of MPP in the estradiol-induced vitellogenin production does not support the participation of ERα. On the other hand, once blocked ERα with MPP, the only manifestation of agonist activity of estradiol would be achieved via ERβ. In conclusion, the present results indicate that vitellogenin production is mainly mediated through ERβ, implying, furthermore

  16. Minimum datasets to establish a CAR-mediated mode of action for rodent liver tumors.

    Science.gov (United States)

    Peffer, Richard C; LeBaron, Matthew J; Battalora, Michael; Bomann, Werner H; Werner, Christoph; Aggarwal, Manoj; Rowe, Rocky R; Tinwell, Helen

    2018-07-01

    Methods for investigating the Mode of Action (MoA) for rodent liver tumors via constitutive androstane receptor (CAR) activation are outlined here, based on current scientific knowledge about CAR and feedback from regulatory agencies globally. The key events (i.e., CAR activation, altered gene expression, cell proliferation, altered foci and increased adenomas/carcinomas) can be demonstrated by measuring a combination of key events and associative events that are markers for the key events. For crop protection products, a primary dataset typically should include a short-term study in the species/strain that showed the tumor response at dose levels that bracket the tumorigenic and non-tumorigenic dose levels. The dataset may vary depending on the species and the test compound. As examples, Case Studies with nitrapyrin (in mice) and metofluthrin (in rats) are described. Based on qualitative differences between the species, the key events leading to tumors in mice or rats by this MoA are not operative in humans. In the future, newer approaches such as a CAR biomarker signature approach and/or in vitro CAR3 reporter assays for mouse, rat and human CAR may eventually be used to demonstrate a CAR MoA is operative, without the need for extensive additional studies in laboratory animals. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

  17. The organic anion transport polypeptide 1d1 (Oatp1d1) mediates hepatocellular uptake of phalloidin and microcystin into skate liver.

    Science.gov (United States)

    Meier-Abt, F; Hammann-Hänni, A; Stieger, B; Ballatori, N; Boyer, J L

    2007-02-01

    Organic anion transporting polypeptides (rodent Oatp; human OATP) mediate cellular uptake of numerous organic compounds including xenobiotic toxins into mammalian hepatocytes. In the little skate Leucoraja erinacea a liver-specific Oatp (Oatp1d1, also called sOatp) has been identified and suggested to represent an evolutionarily ancient precursor of the mammalian liver OATP1B1 (human), Oatp1b2 (rat), and OATP1B3 (human). The present study tested whether Oatp1d1 shares functional transport activity of the xenobiotic oligopeptide toxins phalloidin and microcystin with the mammalian liver Oatps/OATPs. The phalloidin analogue [(3)H]-demethylphalloin was taken up into skate hepatocytes with high affinity (Km approximately 0.4 microM), and uptake could be inhibited by phalloidin and a variety of typical Oatp/OATP substrates such as bromosulfophthalein, bile salts, estrone-3-sulfate, cyclosporine A and high concentrations of microcystin-LR (Ki approximately 150 microM). When expressed in Xenopus laevis oocytes Oatp1d1 increased uptake of demethylphalloin (Km approximately 2.2 microM) and microcystin-LR (Km approximately 27 microM) 2- to 3-fold over water-injected oocytes, whereas the alternative skate liver organic anion transporter, the dimeric Ostalpha/beta, exhibited no phalloidin and only minor microcystin-LR transport. Also, the closest mammalian Oatp1d1 orthologue, the human brain and testis OATP1C1, did not show any phalloidin transport activity. These results demonstrate that the evolutionarily ancient Oatp1d1 is able to mediate uptake of cyclic oligopeptide toxins into skate liver. The findings support the notion that Oatp1d1 is a precursor of the liver-specific mammalian Oatps/OATPs and that its transport properties are closely associated with certain forms of toxic liver injury such as for example protein phosphatase inhibition by the water-borne toxin microcystin.

  18. The organic anion transport polypeptide 1d1 (Oatp1d1) mediates hepatocellular uptake of phalloidin and microcystin into skate liver

    International Nuclear Information System (INIS)

    Meier-Abt, F.; Hammann-Haenni, A.; Stieger, B.; Ballatori, N.; Boyer, J.L.

    2007-01-01

    Organic anion transporting polypeptides (rodent Oatp; human OATP) mediate cellular uptake of numerous organic compounds including xenobiotic toxins into mammalian hepatocytes. In the little skate Leucoraja erinacea a liver-specific Oatp (Oatp1d1, also called sOatp) has been identified and suggested to represent an evolutionarily ancient precursor of the mammalian liver OATP1B1 (human), Oatp1b2 (rat), and OATP1B3 (human). The present study tested whether Oatp1d1 shares functional transport activity of the xenobiotic oligopeptide toxins phalloidin and microcystin with the mammalian liver Oatps/OATPs. The phalloidin analogue [ 3 H]-demethylphalloin was taken up into skate hepatocytes with high affinity (Km ∼ 0.4 μM), and uptake could be inhibited by phalloidin and a variety of typical Oatp/OATP substrates such as bromosulfophthalein, bile salts, estrone-3-sulfate, cyclosporine A and high concentrations of microcystin-LR (Ki ∼ 150 μM). When expressed in Xenopus laevis oocytes Oatp1d1 increased uptake of demethylphalloin (Km ∼ 2.2 μM) and microcystin-LR (Km ∼ 27 μM) 2- to 3-fold over water-injected oocytes, whereas the alternative skate liver organic anion transporter, the dimeric Ostα/β, exhibited no phalloidin and only minor microcystin-LR transport. Also, the closest mammalian Oatp1d1 orthologue, the human brain and testis OATP1C1, did not show any phalloidin transport activity. These results demonstrate that the evolutionarily ancient Oatp1d1 is able to mediate uptake of cyclic oligopeptide toxins into skate liver. The findings support the notion that Oatp1d1 is a precursor of the liver-specific mammalian Oatps/OATPs and that its transport properties are closely associated with certain forms of toxic liver injury such as for example protein phosphatase inhibition by the water-borne toxin microcystin

  19. Role of resveratrol in FOXO1-mediated gluconeogenic gene expression in the liver

    Energy Technology Data Exchange (ETDEWEB)

    Park, Joo-Man; Kim, Tae-Hyun [Department of Biochemistry and Molecular Biology, Center for Chronic Metabolic Disease Research, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Brain Korea 21 Project for Medical Sciences, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Bae, Jin-Sik; Kim, Mi-Young [Department of Biochemistry and Molecular Biology, Center for Chronic Metabolic Disease Research, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Kim, Kyung-Sup [Department of Biochemistry and Molecular Biology, Center for Chronic Metabolic Disease Research, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Brain Korea 21 Project for Medical Sciences, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); The Institute of Genetic Science, Yonsei University College of Medicine, 134 Shinchon-dong, Seodaemoon-gu, Seoul 120-752 (Korea, Republic of); Ahn, Yong-Ho, E-mail: yha111@yuhs.ac [Department of Biochemistry and Molecular Biology, Center for Chronic Metabolic Disease Research, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Brain Korea 21 Project for Medical Sciences, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of)

    2010-12-17

    Research highlights: {yields} Insulin-suppression of PEPCK and G6Pase gene expression is counteracted by resveratrol. {yields} Resveratrol upregulates hepatic gluconeogenic genes by attenuating insulin signaling and deacetylating FOXO1, which are SIRT1-independent in the cytosol and SIRT1-dependent in the nucleus, respectively. {yields} Resveratrol increases the binding activity of Foxo1 to the IRE of PEPCK and G6Pase. -- Abstract: During a state of fasting, the blood glucose level is maintained by hepatic gluconeogenesis. SIRT1 is an important metabolic regulator during nutrient deprivation and the liver-specific knockdown of SIRT1 resulted in decreased glucose production. We hypothesize that SIRT1 is responsible for the upregulation of insulin-suppressed gluconeogenic genes through the deacetylation of FOXO1. Treatment of primary cultured hepatocytes with resveratrol increased insulin-repressed PEPCK and G6Pase mRNA levels, which depend on SIRT1 activity. We found that the resveratrol treatment resulted in a decrease in the phosphorylation of Akt and FOXO1, which are independent of SIRT1 action. Fluorescence microscopy revealed that resveratrol caused the nuclear localization of FOXO1. In the nucleus, FOXO1 is deacetylated by SIRT1, which might make it more accessible to the IRE of the PEPCK and G6Pase promoter, causing an increase in their gene expression. Our results indicate that resveratrol upregulates the expression of gluconeogenic genes by attenuating insulin signaling and by deacetylating FOXO1, which are SIRT1-independent in the cytosol and SIRT1-dependent in the nucleus, respectively.

  20. Role of resveratrol in FOXO1-mediated gluconeogenic gene expression in the liver

    International Nuclear Information System (INIS)

    Park, Joo-Man; Kim, Tae-Hyun; Bae, Jin-Sik; Kim, Mi-Young; Kim, Kyung-Sup; Ahn, Yong-Ho

    2010-01-01

    Research highlights: → Insulin-suppression of PEPCK and G6Pase gene expression is counteracted by resveratrol. → Resveratrol upregulates hepatic gluconeogenic genes by attenuating insulin signaling and deacetylating FOXO1, which are SIRT1-independent in the cytosol and SIRT1-dependent in the nucleus, respectively. → Resveratrol increases the binding activity of Foxo1 to the IRE of PEPCK and G6Pase. -- Abstract: During a state of fasting, the blood glucose level is maintained by hepatic gluconeogenesis. SIRT1 is an important metabolic regulator during nutrient deprivation and the liver-specific knockdown of SIRT1 resulted in decreased glucose production. We hypothesize that SIRT1 is responsible for the upregulation of insulin-suppressed gluconeogenic genes through the deacetylation of FOXO1. Treatment of primary cultured hepatocytes with resveratrol increased insulin-repressed PEPCK and G6Pase mRNA levels, which depend on SIRT1 activity. We found that the resveratrol treatment resulted in a decrease in the phosphorylation of Akt and FOXO1, which are independent of SIRT1 action. Fluorescence microscopy revealed that resveratrol caused the nuclear localization of FOXO1. In the nucleus, FOXO1 is deacetylated by SIRT1, which might make it more accessible to the IRE of the PEPCK and G6Pase promoter, causing an increase in their gene expression. Our results indicate that resveratrol upregulates the expression of gluconeogenic genes by attenuating insulin signaling and by deacetylating FOXO1, which are SIRT1-independent in the cytosol and SIRT1-dependent in the nucleus, respectively.

  1. Positional information in axolotl and mouse limb extracellular matrix is mediated via heparan sulfate and fibroblast growth factor during limb regeneration in the axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Phan, Anne Q; Lee, Jangwoo; Oei, Michelle; Flath, Craig; Hwe, Caitlyn; Mariano, Rachele; Vu, Tiffany; Shu, Cynthia; Dinh, Andrew; Simkin, Jennifer; Muneoka, Ken; Bryant, Susan V; Gardiner, David M

    2015-08-01

    Urodele amphibians are unique among adult vertebrates in their ability to regenerate complex body structures after traumatic injury. In salamander regeneration, the cells maintain a memory of their original position and use this positional information to recreate the missing pattern. We used an in vivo gain-of-function assay to determine whether components of the extracellular matrix (ECM) have positional information required to induce formation of new limb pattern during regeneration. We discovered that salamander limb ECM has a position-specific ability to either inhibit regeneration or induce de novo limb structure, and that this difference is dependent on heparan sulfates that are associated with differential expression of heparan sulfate sulfotransferases. We also discovered that an artificial ECM containing only heparan sulfate was sufficient to induce de novo limb pattern in salamander limb regeneration. Finally, ECM from mouse limbs is capable of inducing limb pattern in axolotl blastemas in a position-specific, developmental-stage-specific, and heparan sulfate-dependent manner. This study demonstrates a mechanism for positional information in regeneration and establishes a crucial functional link between salamander regeneration and mammals.

  2. The effect of trimethoprim on CYP2C8 mediated rosiglitazone metabolism in human liver microsomes and healthy subjects

    Science.gov (United States)

    Hruska, M W; Amico, J A; Langaee, T Y; Ferrell, R E; Fitzgerald, S M; Frye, R F

    2005-01-01

    Aims Rosiglitazone, a thiazolidinedione antidiabetic medication used in the treatment of Type 2 diabetes mellitus, is predominantly metabolized by the cytochrome P450 (CYP) enzyme CYP2C8. The anti-infective drug trimethoprim has been shown in vitro to be a selective inhibitor of CYP2C8. The purpose of this study was to evaluate the effect of trimethoprim on the CYP2C8 mediated metabolism of rosiglitazone in vivo and in vitro. Methods The effect of trimethoprim on the metabolism of rosiglitazone in vitro was assessed in pooled human liver microsomes. The effect in vivo was determined by evaluating rosiglitazone pharmacokinetics in the presence and absence of trimethoprim. Eight healthy subjects (four men and four women) completed a randomized, cross-over study. Subjects received single dose rosiglitazone (8 mg) in the presence and absence of trimethoprim 200 mg given twice daily for 5 days. Results Trimethoprim inhibited rosiglitazone metabolism both in vitro and in vivo. Inhibition of rosiglitazone para-hydroxylation by trimethoprim in vitro was found to be competitive with apparent Ki and IC50 values of 29 µm and 54.5 µm, respectively. In the presence of trimethoprim, rosiglitazone plasma AUC was increased by 31% (P = 0.01) from 2774 ± 645 µg l−1 h to 3643 ± 1051 µg l−1 h (95% confidence interval (Cl) for difference 189, 1549), and half-life was increased by 27% (P = 0.006) from 3.3 ± 0.5 to 4.2 ± 0.8 h (95% Cl for difference 0.36, 1.5). Trimethoprim reduced the para-O-sulphate rosiglitazone/rosiglitazone and the N-desmethylrosiglitazone/rosiglitazone AUC(0–24) ratios by 22% and 38%, respectively. Conclusions These results indicate that trimethoprim is a competitive inhibitor of CYP2C8-mediated rosiglitazone metabolism in vitro and that trimethoprim administration increases plasma rosiglitazone concentrations in healthy subjects. PMID:15606443

  3. Functional hepatocellular regeneration measured by hepatobiliary scintigraphy, functional regeneration or functional hepatocytes?

    NARCIS (Netherlands)

    Olthof, Pim B.; Cieslak, Kasia P.; Bennink, Roelof J.; van Gulik, Thomas M.

    2016-01-01

    In a recent issue of this journal, Fernandes et al(1) reported on functional hepatocellular regeneration in elderly patients undergoing hepatectomy. They used (99m) Tc-mebrofinin HBS to quantify liver function before and after surgery and concluded that functional regeneration is already present at

  4. Systemic agonistic anti-CD40 treatment of tumor bearing mice modulates hepatic myeloid suppressive cells and causes immune-mediated liver damage

    Science.gov (United States)

    Medina-Echeverz, José; Ma, Chi; Duffy, Austin; Eggert, Tobias; Hawk, Nga; Kleiner, David E.; Korangy, Firouzeh; Greten, Tim F.

    2015-01-01

    Immune stimulatory monoclonal antibodies are currently evaluated as anti tumor agents. Although overall toxicity appears to be moderate, liver toxicities have been reported and are not completely understood. We studied the effect of systemic CD40 antibody treatment on myeloid cells in spleen and liver. Naïve and tumor-bearing mice were treated systemically with agonistic anti-CD40 antibody. Immune cell subsets in liver and spleen, serum transaminases and liver histologies were analyzed after antibody administration. Nox2−/−, Cd40−/− as well as bone marrow chimeric mice were used to study the mechanism by which agonistic anti-CD40 mediates its effects in vivo. Suppressor function of murine and human tumor-induced myeloid derived suppressive cells was studied upon CD40 ligation. Agonistic CD40 antibody caused liver damage within 24 hours after injection in two unrelated tumor models and mice strains. Using bone marrow chimeras we demonstrated that CD40 antibody-induced hepatitis in tumor-bearing mice was dependent on the presence of CD40-expressing hematopoietic cells. Agonistic CD40 ligation-dependent liver damage was induced by the generation of reactive oxygen species. Furthermore, agonistic CD40 antibody resulted in increased CD80 and CD40 positive liver CD11b+Gr-1+ immature myeloid cells. CD40 ligation on tumor-induced murine and human CD14+HLA-DRlow PBMC from cancer patients reduced their immune suppressor function. Collectively, agonistic CD40 antibody treatment activated tumor-induced, myeloid cells, caused myeloid dependent hepatotoxicity and ameliorated the suppressor function of murine and human MDSC. Collectively, our data suggests that CD40 may mature immunosuppressive myeloid cells and thereby cause liver damage in mice with an accumulation of tumor-induced hepatic MDSC. PMID:25637366

  5. Esculetin ameliorates hepatic fibrosis in high fat diet induced non-alcoholic fatty liver disease by regulation of FoxO1 mediated pathway.

    Science.gov (United States)

    Pandey, Anuradha; Raj, Priyank; Goru, Santosh Kumar; Kadakol, Almesh; Malek, Vajir; Sharma, Nisha; Gaikwad, Anil Bhanudas

    2017-08-01

    Non-alcoholic fatty liver disease (NAFLD), a chronic metabolic disorder is associated with oxidative stress, inflammation and fibrotic cascades. In this study, we aimed to examine the effects of Esculetin, a well-known anti-oxidant on TGF-β1 mediated liver fibrosis and FoxO1 activity. A non-genetic murine model for NAFLD was developed by chronic high fat diet (HFD) (58% calories from fats) feeding in Wistar rats. The plasma biochemical parameters, liver function tests, oxidative stress, and histopathological alterations were assessed. The alterations in extracellular matrix (ECM) deposition and FoxO1 activity were assessed by immunohistochemistry. The aberrations in plasma parameters, liver functioning, morphometric and microscopic changes in liver structure of HFD fed rats were significantly improved by treatment with Esculetin. Liver fibrosis, identified in the form of collagen deposition and expression of fibrotic proteins like TGF-β1 and fibronectin was also markedly controlled by Esculetin. The expression of phospho-FoxO1 was found to be reduced in HFD fed rats' liver, showing an increase in activation of FoxO1 under insulin resistant and hyperglycemic states. Esculetin treatment could improve phospho-FoxO1 expression, thus showing its ability to act on Akt/PI3K/FoxO1 pathway. As per the previous studies, a potential therapy for NAFLD may be the one with multi-faceted actions on insulin resistance, oxidative stress, inflammation and fibrosis. This study demonstrates the efficiency of Esculetin in improving liver fibrosis in HFD induced NAFLD. Copyright © 2017 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  6. The effect of vanadate on receptor-mediated endocytosis of asialoorosomucoid in rat liver parenchymal cells

    International Nuclear Information System (INIS)

    Kindberg, G.M.; Gudmundsen, O.; Berg, T.

    1990-01-01

    Vanadate is a phosphate analogue that inhibits enzymes involved in phosphate release and transfer reactions. Since such reactions may play important roles in endocytosis, we studied the effects of vanadate on various steps in receptor-mediated endocytosis of asialoorosomucoid labeled with 125I-tyramine-cellobiose (125I-TC-AOM). The labeled degradation products formed from 125I-TC-AOM are trapped in the lysosomes and may therefore serve as lysosomal markers in subcellular fractionation studies. Vanadate reduced the amount of active surface asialoglycoprotein receptors approximately 70%, but had no effect on the rate of internalization and retroendocytosis of ligand. The amount of surface asialoglycoprotein receptors can be reduced by lowering the incubation temperature gradually from 37 to 15 degrees C; vanadate affected only the temperature--sensitive receptors. Vanadate inhibited degradation of 125I-TC-AOM 70-80%. Degradation was much more sensitive to vanadate than binding; half-maximal effects were seen at approximately 1 mM vanadate for binding and approximately 0.1 mM vanadate for degradation. By subcellular fractionation in sucrose and Nycodenz gradients, it was shown that vanadate completely prevented the transfer of 125I-TC-AOM from endosomes to lysosomes. Therefore, the inhibition of degradation by vanadate was indirect; in the presence of vanadate, ligand did not gain access to the lysosomes. The limited degradation in the presence of vanadate took place in a prelysosomal compartment. Vanadate did not affect cell viability and ATP content

  7. High circulatory leptin mediated NOX-2-peroxynitrite-miR21 axis activate mesangial cells and promotes renal inflammatory pathology in nonalcoholic fatty liver disease

    Directory of Open Access Journals (Sweden)

    Firas Alhasson

    2018-07-01

    Full Text Available High circulatory insulin and leptin followed by underlying inflammation are often ascribed to the ectopic manifestations in non-alcoholic fatty liver disease (NAFLD but the exact molecular pathways remain unclear. We have shown previously that CYP2E1-mediated oxidative stress and circulating leptin in NAFLD is associated with renal disease severity. Extending the studies, we hypothesized that high circulatory leptin in NAFLD causes renal mesangial cell activation and tubular inflammation via a NOX2 dependent pathway that upregulates proinflammatory miR21. High-fat diet (60% kcal was used to induce fatty liver phenotype with parallel insulin and leptin resistance. The kidneys were probed for mesangial cell activation and tubular inflammation that showed accelerated NASH phenotype and oxidative stress in the liver. Results showed that NAFLD kidneys had significant increases in α-SMA, a marker of mesangial cell activation, miR21 levels, tyrosine nitration and renal inflammation while they were significantly decreased in leptin and p47 phox knockout mice. Micro RNA21 knockout mice showed decreased tubular immunotoxicity and proinflammatory mediator release. Mechanistically, use of NOX2 siRNA or apocynin,phenyl boronic acid (FBA, DMPO or miR21 antagomir inhibited leptin primed-miR21-mediated mesangial cell activation in vitro suggesting a direct role of leptin-mediated NOX-2 in miR21-mediated mesangial cell activation. Finally, JAK-STAT inhibitor completely abrogated the mesangial cell activation in leptin-primed cells suggesting that leptin signaling in the mesangial cells depended on the JAK-STAT pathway. Taken together the study reports a novel mechanistic pathway of leptin-mediated renal inflammation that is dependent on NOX-2-miR21 axis in ectopic manifestations underlying NAFLD-induced co-morbidities. Keywords: Leptin, NOX-2, NADPH, Mesangial cells, miR21, Oxidative stress, NAFLD, JAK/STAT, siRNA

  8. CD151 supports VCAM-1-mediated lymphocyte adhesion to liver endothelium and is upregulated in chronic liver disease and hepatocellular carcinoma.

    Science.gov (United States)

    Wadkin, James C R; Patten, Daniel A; Kamarajah, Sivesh K; Shepherd, Emma L; Novitskaya, Vera; Berditchevski, Fedor; Adams, David H; Weston, Chris J; Shetty, Shishir

    2017-08-01

    CD151, a member of the tetraspanin family of receptors, is a lateral organizer and modulator of activity of several families of transmembrane proteins. It has been implicated in the development and progression of several cancers, but its role in chronic inflammatory disease is less well understood. Here we show that CD151 is upregulated by distinct microenvironmental signals in a range of chronic inflammatory liver diseases and in primary liver cancer, in which it supports lymphocyte recruitment. CD151 was highly expressed in endothelial cells of the hepatic sinusoids and neovessels developing in fibrotic septa and tumor margins. Primary cultures of human hepatic sinusoidal endothelial cells (HSECs) expressed CD151 at the cell membrane and in intracellular vesicles. CD151 was upregulated by VEGF and HepG2 conditioned media but not by proinflammatory cytokines. Confocal microscopy confirmed that CD151 colocalized with the endothelial adhesion molecule/immunoglobulin superfamily member, VCAM-1. Functional flow-based adhesion assays with primary human lymphocytes and HSECs demonstrated a 40% reduction of lymphocyte adhesion with CD151 blockade. Inhibition of lymphocyte adhesion was similar between VCAM-1 blockade and a combination of CD151/VCAM-1 blockade, suggesting a collaborative role between the two receptors. These studies demonstrate that CD151 is upregulated within the liver during chronic inflammation, where it supports lymphocyte recruitment via liver endothelium. We propose that CD151 regulates the activity of VCAM-1 during lymphocyte recruitment to the human liver and could be a novel anti-inflammatory target in chronic liver disease and hepatocellular cancer prevention. NEW & NOTEWORTHY Chronic hepatitis is characterized by lymphocyte accumulation in liver tissue, which drives fibrosis and carcinogenesis. Here, we demonstrate for the first time that the tetraspanin CD151 supports lymphocyte adhesion to liver endothelium. We show that CD151 is upregulated

  9. CRISPR-Mediated Genomic Deletion of Sox2 in the Axolotl Shows a Requirement in Spinal Cord Neural Stem Cell Amplification during Tail Regeneration

    Directory of Open Access Journals (Sweden)

    Ji-Feng Fei

    2014-09-01

    Full Text Available The salamander is the only tetrapod that functionally regenerates all cell types of the limb and spinal cord (SC and thus represents an important regeneration model, but the lack of gene-knockout technology has limited molecular analysis. We compared transcriptional activator-like effector nucleases (TALENs and clustered regularly interspaced short palindromic repeats (CRISPRs in the knockout of three loci in the axolotl and find that CRISPRs show highly penetrant knockout with less toxic effects compared to TALENs. Deletion of Sox2 in up to 100% of cells yielded viable F0 larvae with normal SC organization and ependymoglial cell marker expression such as GFAP and ZO-1. However, upon tail amputation, neural stem cell proliferation was inhibited, resulting in spinal-cord-specific regeneration failure. In contrast, the mesodermal blastema formed normally. Sox3 expression during development, but not regeneration, most likely allowed embryonic survival and the regeneration-specific phenotype. This analysis represents the first tissue-specific regeneration phenotype from the genomic deletion of a gene in the axolotl.

  10. Effect of sodium-glucose cotransporter 2 (SGLT2) inhibition on weight loss is partly mediated by liver-brain-adipose neurocircuitry.

    Science.gov (United States)

    Sawada, Yoshikazu; Izumida, Yoshihiko; Takeuchi, Yoshinori; Aita, Yuichi; Wada, Nobuhiro; Li, EnXu; Murayama, Yuki; Piao, Xianying; Shikama, Akito; Masuda, Yukari; Nishi-Tatsumi, Makiko; Kubota, Midori; Sekiya, Motohiro; Matsuzaka, Takashi; Nakagawa, Yoshimi; Sugano, Yoko; Iwasaki, Hitoshi; Kobayashi, Kazuto; Yatoh, Shigeru; Suzuki, Hiroaki; Yagyu, Hiroaki; Kawakami, Yasushi; Kadowaki, Takashi; Shimano, Hitoshi; Yahagi, Naoya

    2017-11-04

    Sodium-glucose cotransporter 2 (SGLT2) inhibitors have both anti-diabetic and anti-obesity effects. However, the precise mechanism of the anti-obesity effect remains unclear. We previously demonstrated that the glycogen depletion signal triggers lipolysis in adipose tissue via liver-brain-adipose neurocircuitry. In this study, therefore, we investigated whether the anti-obesity mechanism of SGLT2 inhibitor is mediated by this mechanism. Diet-induced obese mice were subjected to hepatic vagotomy (HVx) or sham operation and loaded with high fat diet containing 0.015% tofogliflozin (TOFO), a highly selective SGLT2 inhibitor, for 3 weeks. TOFO-treated mice showed a decrease in fat mass and the effect of TOFO was attenuated in HVx group. Although both HVx and sham mice showed a similar level of reduction in hepatic glycogen by TOFO treatment, HVx mice exhibited an attenuated response in protein phosphorylation by protein kinase A (PKA) in white adipose tissue compared with the sham group. As PKA pathway is known to act as an effector of the liver-brain-adipose axis and activate triglyceride lipases in adipocytes, these results indicated that SGLT2 inhibition triggered glycogen depletion signal and actuated liver-brain-adipose axis, resulting in PKA activation in adipocytes. Taken together, it was concluded that the effect of SGLT2 inhibition on weight loss is in part mediated via the liver-brain-adipose neurocircuitry. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Zingerone Suppresses Liver Inflammation Induced by Antibiotic Mediated Endotoxemia through Down Regulating Hepatic mRNA Expression of Inflammatory Markers in Pseudomonas aeruginosa Peritonitis Mouse Model

    OpenAIRE

    Kumar, Lokender; Chhibber, Sanjay; Harjai, Kusum

    2014-01-01

    Antibiotic-induced endotoxin release is associated with high mortality rate even when appropriate antibiotics are used for the treatment of severe infections in intensive care units. Since liver is involved in systemic clearance and detoxification of endotoxin hence it becomes a primary target organ for endotoxin mediated inflammation. Currently available anti-inflammatory drugs give rise to serious side effects. Hence, there is an urgent need for safe and effective anti-inflammatory therapy....

  12. Natural indoles, indole-3-carbinol (I3C and 3,3'-diindolylmethane (DIM, attenuate staphylococcal enterotoxin B-mediated liver injury by downregulating miR-31 expression and promoting caspase-2-mediated apoptosis.

    Directory of Open Access Journals (Sweden)

    Philip B Busbee

    Full Text Available Staphylococcal enterotoxin B (SEB is a potent superantigen capable of inducing inflammation characterized by robust immune cell activation and proinflammatory cytokine release. Exposure to SEB can result in food poisoning as well as fatal conditions such as toxic shock syndrome. In the current study, we investigated the effect of natural indoles including indole-3-carbinol (I3C and 3,3'-diindolylmethane (DIM on SEB-mediated liver injury. Injection of SEB into D-galactosamine-sensitized female C57BL/6 mice resulted in liver injury as indicated by an increase in enzyme aspartate transaminase (AST levels, induction of inflammatory cytokines, and massive infiltration of immune cells into the liver. Administration of I3C and DIM (40 mg/kg, by intraperitonal injection, attenuated SEB-induced acute liver injury, as evidenced by decrease in AST levels, inflammatory cytokines and cellular infiltration in the liver. I3C and DIM triggered apoptosis in SEB-activated T cells primarily through activation of the intrinsic mitochondrial pathway. In addition, inhibitor studies involving caspases revealed that I3C and DIM-mediated apoptosis in these activated cells was dependent on caspase-2 but independent of caspase-8, 9 and 3. In addition, I3C and DIM caused a decrease in Bcl-2 expression. Both compounds also down-regulated miR-31, which directly targets caspase-2 and influences apoptosis in SEB-activated cells. Our data demonstrate for the first time that indoles can effectively suppress acute hepatic inflammation caused by SEB and that this may be mediated by decreased expression of miR-31 and consequent caspase-2-dependent apoptosis in T cells.

  13. My Regeneration:

    DEFF Research Database (Denmark)

    Carter, Dale

    2017-01-01

    and cultural referents shows that it offers an index to the album. Using its frontier setting and a variety of sacred and secular myths, symbols and icons, ‘Heroes and Villains,’ like Smile as a whole, offers historically-informed visions of national decline, crisis and regeneration that are at once critical...

  14. Inhibition of type I NKT cells by retinoids or following sulfatide-mediated activation of type II NKT cells attenuates alcoholic liver disease

    Science.gov (United States)

    Maricic, Igor; Sheng, Huiming; Marrero, Idania; Seki, Ehikiro; Kisseleva, Tatiana; Chaturvedi, Som; Molle, Natasha; Mathews, K. Stephanie; Gao, Bin; Kumar, Vipin

    2015-01-01

    Innate immune mechanisms leading to liver injury following chronic alcohol ingestion are poorly understood. Natural killer T (NKT) cells, enriched in the liver and comprised of at least two distinct subsets, type I and type II, recognize different lipid antigens presented by CD1d molecules. We have investigated whether differential activation of NKT cell subsets orchestrates inflammatory events leading to alcoholic liver disease (ALD). We found that following chronic plus binge feeding of Lieber-DeCarli liquid diet in male C57BL/6 mice, type I but not type II NKT cells are activated leading to recruitment of inflammatory Gr-1highCD11b+ cells into liver. A central finding is that liver injury following alcohol feeding is dependent upon type I NKT cells. Thus liver injury is significantly inhibited in Jα18−/− mice deficient in type I NKT cells as well as following their inactivation by sulfatide-mediated activation of type II NKT cells. Furthermore we have identified a novel pathway involving all-trans retinoic acid (ATRA) and its receptor RARγ signaling that inhibits type I NKT cells and consequently ALD. A semi-quantitative PCR analysis of hepatic gene expression of some of the key proinflammatory molecules shared in human disease indicated that their upregulation in ALD is dependent upon type I NKT cells. Conclusion Type I but not type II NKT cells become activated following alcohol feeding. Type I NKT cells-induced inflammation and neutrophil recruitment results in liver tissue damage while type II NKT cells protect from injury in ALD. Inhibition of type I NKT cells by retinoids or by sulfatide prevents ALD. Since the CD1d pathway is highly conserved between mice and humans, NKT cell subsets might be targeted for potential therapeutic intervention in ALD. PMID:25477000

  15. PHP14 regulates hepatic stellate cells migration in liver fibrosis via mediating TGF-β1 signaling to PI3Kγ/AKT/Rac1 pathway.

    Science.gov (United States)

    Xu, Anjian; Li, Yanmeng; Zhao, Wenshan; Hou, Fei; Li, Xiaojin; Sun, Lan; Chen, Wei; Yang, Aiting; Wu, Shanna; Zhang, Bei; Yao, Jingyi; Wang, Huan; Huang, Jian

    2018-02-01

    Hepatic fibrosis is characterized by the activation of hepatic stellate cells (HSCs). Migration of the activated HSCs to the site of injury is one of the key characteristics during the wound healing process. We have previously demonstrated that 14 kDa phosphohistidine phosphatase (PHP14) is involved in migration and lamellipodia formation of HSCs. However, the role of PHP14 in liver fibrosis remains unknown. In this study, we first assessed PHP14 expression and distribution in liver fibrotic tissues using western blot, immunohistochemistry, and double immunofluorescence staining. Next, we investigated the role of PHP14 in liver fibrosis and, more specifically, the migration of HSCs by Transwell assay and 3D collagen matrices assay. Finally, we explored the possible molecular mechanisms of the effects of PHP14 on these processes. Our results show that the PHP14 expression is up-regulated in fibrotic liver and mainly in HSCs. Importantly, TGF-β1 can induce PHP14 expression in HSCs accompanied with the activation of HSCs. Consistent with the previous study, PHP14 promotes HSCs migration, especially, promotes 3D floating collagen matrices contraction but inhibits stressed-released matrices contraction. Mechanistically, the PI3Kγ/AKT/Rac1 pathway is involved in migration regulated by PHP14. Moreover, PHP14 specifically mediates the TGF-β1 signaling to PI3Kγ/AKT pathway and regulates HSC migration, and thus participates in liver fibrosis. Our study identified the role of PHP14 in liver fibrosis, particularly HSC migration, and suggested a novel mediator of transducting TGF-β1 signaling to PI3Kγ/AKT/Rac1 pathway. PHP14 is up-regulated in fibrotic liver and activated hepatic stellate cells. The expression of PHP14 is induced by TGF-β1. The migration of hepatic stellate cells is regulated by PHP14. PHP14 is a mediator of TGF-β1 signaling to PI3Kγ/AKT/Rac1 pathway in hepatic stellate cells.

  16. Precise let-7 expression levels balance organ regeneration against tumor suppression

    Science.gov (United States)

    Wu, Linwei; Nguyen, Liem H; Zhou, Kejin; de Soysa, T Yvanka; Li, Lin; Miller, Jason B; Tian, Jianmin; Locker, Joseph; Zhang, Shuyuan; Shinoda, Gen; Seligson, Marc T; Zeitels, Lauren R; Acharya, Asha; Wang, Sam C; Mendell, Joshua T; He, Xiaoshun; Nishino, Jinsuke; Morrison, Sean J; Siegwart, Daniel J; Daley, George Q; Shyh-Chang, Ng; Zhu, Hao

    2015-01-01

    The in vivo roles for even the most intensely studied microRNAs remain poorly defined. Here, analysis of mouse models revealed that let-7, a large and ancient microRNA family, performs tumor suppressive roles at the expense of regeneration. Too little or too much let-7 resulted in compromised protection against cancer or tissue damage, respectively. Modest let-7 overexpression abrogated MYC-driven liver cancer by antagonizing multiple let-7 sensitive oncogenes. However, the same level of overexpression blocked liver regeneration, while let-7 deletion enhanced it, demonstrating that distinct let-7 levels can mediate desirable phenotypes. let-7 dependent regeneration phenotypes resulted from influences on the insulin-PI3K-mTOR pathway. We found that chronic high-dose let-7 overexpression caused liver damage and degeneration, paradoxically leading to tumorigenesis. These dose-dependent roles for let-7 in tissue repair and tumorigenesis rationalize the tight regulation of this microRNA in development, and have important implications for let-7 based therapeutics. DOI: http://dx.doi.org/10.7554/eLife.09431.001 PMID:26445246

  17. Parenteral Nutrition in Liver Resection

    Directory of Open Access Journals (Sweden)

    Carlo Chiarla

    2012-01-01

    Full Text Available Albeit a very large number of experiments have assessed the impact of various substrates on liver regeneration after partial hepatectomy, a limited number of clinical studies have evaluated artificial nutrition in liver resection patients. This is a peculiar topic because many patients do not need artificial nutrition, while several patients need it because of malnutrition and/or prolonged inability to feeding caused by complications. The optimal nutritional regimen to support liver regeneration, within other postoperative problems or complications, is not yet exactly defined. This short review addresses relevant aspects and potential developments in the issue of postoperative parenteral nutrition after liver resection.

  18. Role of cytochrome P450-mediated metabolism and involvement of reactive metabolite formations on antiepileptic drug-induced liver injuries.

    Science.gov (United States)

    Sasaki, Eita; Yokoi, Tsuyoshi

    2018-01-01

    Several drugs have been withdrawn from the market or restricted to avoid unexpected adverse outcomes. Drug-induced liver injury (DILI) is a serious issue for drug development. Among DILIs, idiosyncratic DILIs have been a serious problem in drug development and clinical uses. Idiosyncratic DILI is most often unrelated to pharmacological effects or the dosing amount of a drug. The number of drugs that cause idiosyncratic DILI continue to grow in part because no practical preclinical tests have emerged that can identify drug candidates with the potential for developing idiosyncratic DILIs. Nevertheless, the implications of drug metabolism-related factors and immune-related factors on idiosyncratic DILIs has not been fully clarified because this toxicity can not be reproduced in animals. Therefore, accumulated evidence for the mechanisms of the idiosyncratic toxicity has been limited to only in vitro studies. This review describes current knowledge of the effects of cytochrome P450 (CYP)-mediated metabolism and its detoxification abilities based on studies of idiosyncratic DILI animal models developed recently. This review also focused on antiepileptic drugs, phenytoin (diphenyl hydantoin, DPH) and carbamazepine (CBZ), which have rarely caused severe adverse reactions, such as fulminant hepatitis, and have been recognized as sources of idiosyncratic DILI. The studies of animal models of idiosyncratic DILIs have produced new knowledge of chronic administration, CYP inductions/inhibitions, glutathione contents, and immune-related factors for the initiation of idiosyncratic DILIs. Considering changes in the drug metabolic profile and detoxification abilities, idiosyncratic DILIs caused by antiepileptic drugs will lead to understanding the mechanisms of these DILIs.

  19. Bone Marrow-Derived Mesenchymal Stem Cells Attenuate Immune-Mediated Liver Injury and Compromise Virus Control During Acute Hepatitis B Virus Infection in Mice.

    Science.gov (United States)

    Qu, Mengmeng; Yuan, Xu; Liu, Dan; Ma, Yuhong; Zhu, Jun; Cui, Jun; Yu, Mengxue; Li, Changyong; Guo, Deyin

    2017-06-01

    Mesenchymal stem cells (MSCs) have been used as therapeutic tools not only for their ability to differentiate toward different cells, but also for their unique immunomodulatory properties. However, it is still unknown how MSCs may affect immunity during hepatitis B virus (HBV) infection. This study was designed to explore the effect of bone marrow-derived MSCs (BM-MSCs) on hepatic natural killer (NK) cells in a mouse model of acute HBV infection. Mice were injected with 1 × 10 6 BM-MSCs, which stained with chloromethyl derivatives of fluorescein diacetate fluorescent probe, 24 h before hydrodynamic injection of viral DNA (pHBV1.3) through the tail vein. In vivo imaging system revealed that BM-MSCs were accumulated in the injured liver, and they attenuated immune-mediated liver injury during HBV infection, as shown by lower alanine aminotransferase levels, reduced proinflammatory cytokine production, and decreased inflammatory cell infiltration in the liver. Importantly, administration of BM-MSCs restrained the increased expression of natural-killer group 2, member D (NKG2D), an important receptor required for NK cell activation in the liver from HBV-infected mice. BM-MSCs also reduced NKG2D expression on NK cells and suppressed the cytotoxicity of NK cells in vitro. Furthermore, BM-MSC-derived transforming growth factor-β1 suppressed NKG2D expression on NK cells. As a consequence, BM-MSC treatment enhanced HBV gene expression and replication in vivo. These results demonstrate that adoptive transfer of BM-MSCs influences innate immunity and limits immune-mediated liver injury during acute HBV infection by suppressing NK cell activity. Meanwhile, the effect of BM-MSCs on prolonging virus clearance needs to be considered in the future.

  20. Detection of single-nucleotide polymorphisms using an ON-OFF switching of regenerated biosensor based on a locked nucleic acid-integrated and toehold-mediated strand displacement reaction.

    Science.gov (United States)

    Gao, Zhong Feng; Ling, Yu; Lu, Lu; Chen, Ning Yu; Luo, Hong Qun; Li, Nian Bing

    2014-03-04

    Although various strategies have been reported for single-nucleotide polymorphisms (SNPs) detection, development of a time-saving, specific, and regenerated electrochemical sensing platform still remains a realistic goal. In this study, an ON-OFF switching of a regenerated biosensor based on a locked nucleic acid (LNA)-integrated and toehold-mediated strand displacement reaction technique is constructed for detection of SNPs. The LNA-integrated and methylene blue-labeled capture probe with an external toehold is designed to switch on the sensing system. The mutant-type DNA probe completes complementary with the capture probe to trigger the strand displacement reaction, which switches off the sensing system. However, when the single-base mismatched wild-type DNA probe is presented, the strand displacement reaction cannot be achieved; therefore, the sensing system still keeps the ON state. This DNA sensor is stable over five reuses. We further testify that the LNA-integrated sequence has better recognition ability for SNPs detection compared to the DNA-integrated sequence. Moreover, this DNA senor exhibits a remarkable discrimination capability of SNPs among abundant wild-type targets and 6000-fold (m/m) excess of genomic DNA. In addition, it is selective enough in complex and contaminant-ridden samples, such as human urine, soil, saliva, and beer. Overall, these results demonstrate that this reliable DNA sensor is easy to be fabricated, simple to operate, and stable enough to be readily regenerated.

  1. Adzuki bean ameliorates hepatic lipogenesis and proinflammatory mediator expression in mice fed a high-cholesterol and high-fat diet to induce nonalcoholic fatty liver disease.

    Science.gov (United States)

    Kim, Sera; Hong, Jihye; Jeon, Raok; Kim, Hyun-Sook

    2016-01-01

    Nonalcoholic fatty liver disease (NAFLD) is a simple steatosis, in which fat accumulates more than 5% in the liver, and regarded as most common liver diseases worldwide. Because NAFLD can be developed to severe liver disease and correlated with metabolic disease, its importance is currently emphasized. Occurrence of NAFLD is strongly related to dietary patterns and lifestyles; therefore, the suggestion of physiologically beneficial food is essential. Based on these, adzuki beans containing anthocyanin, catechin, and adzukisaponin are suggested as a health-beneficial food. Moreover, the effects of adzuki beans on metabolic improvement are not well established through the in vivo studies. Therefore, this study hypothesized that adzuki beans can alleviate lipid accumulation and oxidative stress-mediated inflammation in high-cholesterol and high-fat diet-induced NALFD mice. To demonstrate its effects, 6-week-old C57BL/6 male mice were allocated into 4 groups and fed a normal diet (ND), a high-cholesterol and high-fat diet (HCD), and HCD with 10% and 20% adzuki bean for 10 weeks. The result shows that fasting blood glucose, serum and hepatic triglyceride and cholesterol levels, and antioxidative enzyme activity ameliorated in the adzuki bean groups (P hepatic lipogenesis, such as adiponectin, AMP-activated protein kinase α, sterol regulatory element-binding protein 1c, fatty acid synthase, carnitine palmitoyltransferase 1, 3-hydroxy-3-methyl-glutaryl-CoA reductase, and apolipoprotein B, as well as proinflammatory mediators, such as tumor necrosis factor α, nuclear factor κB, and caspase-3, improved in both experimental groups (P hepatic messenger RNA expression of lipogenic and inflammatory mediators in NAFLD. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Interleukin 17-producing γδT cells promote hepatic regeneration in mice.

    Science.gov (United States)

    Rao, Raghavendra; Graffeo, Christopher S; Gulati, Rishabh; Jamal, Mohsin; Narayan, Suchithra; Zambirinis, Constantinos P; Barilla, Rocky; Deutsch, Michael; Greco, Stephanie H; Ochi, Atsuo; Tomkötter, Lena; Blobstein, Reuven; Avanzi, Antonina; Tippens, Daniel M; Gelbstein, Yisroel; Van Heerden, Eliza; Miller, George

    2014-08-01

    Subsets of leukocytes synergize with regenerative growth factors to promote hepatic regeneration. γδT cells are early responders to inflammation-induced injury in a number of contexts. We investigated the role of γδT cells in hepatic regeneration using mice with disruptions in Tcrd (encodes the T-cell receptor δ chain) and Clec7a (encodes C-type lectin domain family 7 member a, also known as DECTIN1). We performed partial hepatectomies on wild-type C57BL/6, CD45.1, Tcrd(-/-), or Clec7a(-/-) mice. Cells were isolated from livers of patients and mice via mechanical and enzymatic digestion. γδT cells were purified by fluorescence-activated cell sorting. In mice, partial hepatectomy up-regulated expression of CCL20 and ligands of Dectin-1, which was associated with recruitment and activation of γδT cells and their increased production of interleukin (IL)-17 family cytokines. Recruited γδT cells induced production of IL-6 by antigen-presenting cells and suppressed expression of interferon gamma by natural killer T cells, promoting hepatocyte proliferation. Absence of IL-17-producing γδT cells or deletion of Dectin-1 prevented development of regenerative phenotypes in subsets of innate immune cells. This slowed liver regeneration and was associated with reduced expression of regenerative growth factors and cell cycle regulators. Conversely, exogenous administration of IL-17 family cytokines or Dectin-1 ligands promoted regeneration. More broadly, we found that γδT cells are required for inflammatory responses mediated by IL-17 and Dectin-1. γδT cells regulate hepatic regeneration by producing IL-22 and IL-17, which have direct mitogenic effects on hepatocytes and promote a regenerative phenotype in hepatic leukocytes, respectively. Dectin-1 ligation is required for γδT cells to promote hepatic regeneration. Copyright © 2014 AGA Institute. Published by Elsevier Inc. All rights reserved.

  3. Rat Liver Enzyme Release Depends on Blood Flow-Bearing Physical Forces Acting in Endothelium Glycocalyx rather than on Liver Damage

    Directory of Open Access Journals (Sweden)

    Julieta A. Díaz-Juárez

    2017-01-01

    Full Text Available We have found selective elevation of serum enzyme activities in rats subjected to partial hepatectomy (PH, apparently controlled by hemodynamic flow-bearing physical forces. Here, we assess the involvement of stretch-sensitive calcium channels and calcium mobilization in isolated livers, after chemical modifications of the endothelial glycocalyx and changing perfusion directionality. Inhibiting in vivo protein synthesis, we found that liver enzyme release is influenced by de novo synthesis of endothelial glycocalyx components, and released enzymes are confined into a liver “pool.” Moreover, liver enzyme release depended on extracellular calcium entry possibly mediated by stretch-sensitive calcium channels, and this endothelial-mediated mechanotransduction in liver enzyme release was also evidenced by modifying the glycocalyx carbohydrate components, directionality of perfusing flow rate, and the participation of nitric oxide (NO and malondialdehyde (MDA, leading to modifications in the intracellular distribution of these enzymes mainly as nuclear enrichment of “mitochondrial” enzymes. In conclusion, the flow-induced shear stress may provide fine-tuned control of released hepatic enzymes through mediation by the endothelium glycocalyx, which provides evidence of a biological role of the enzyme release rather to be merely a biomarker for evaluating hepatotoxicity and liver damage, actually positively influencing progression of liver regeneration in mammals.

  4. Enzymatic, urease-mediated mineralization of gellan gum hydrogel with calcium carbonate, magnesium-enriched calcium carbonate and magnesium carbonate for bone regeneration applications

    DEFF Research Database (Denmark)

    Douglas, Timothy; Lapa, Agata; Samal, Sangram K.

    carbonate to generate composite biomaterials for bone regeneration. GG is an inexpensive, biotechnologically produced anionic polysaccharide, from which hydrogels for cartilage regeneration have been formed by crosslinking with divalent ions[3]. Methods: GG hydrogels were loaded with the enzyme urease...... by incubation in 5% (w/v) urease solution and mineralized for 5 days in five different media denoted as UA, UB, UC, UD and UE, which contained urea (0.17 M) and different concentrations of CaCl2 and MgCl2 (270:0, 202.5:67.5, 135:135, 67.5:202.5 and 0:250, respectively (mmol dm-3)). Discs were autoclaved...

  5. Mediatization

    DEFF Research Database (Denmark)

    Hjarvard, Stig

    2017-01-01

    Mediatization research shares media effects studies' ambition of answering the difficult questions with regard to whether and how media matter and influence contemporary culture and society. The two approaches nevertheless differ fundamentally in that mediatization research seeks answers...... to these general questions by distinguishing between two concepts: mediation and mediatization. The media effects tradition generally considers the effects of the media to be a result of individuals being exposed to media content, i.e. effects are seen as an outcome of mediated communication. Mediatization...... research is concerned with long-term structural changes involving media, culture, and society, i.e. the influences of the media are understood in relation to how media are implicated in social and cultural changes and how these processes come to create new conditions for human communication and interaction...

  6. Thrombospondin-1 expression may be implicated in liver atrophic mechanism due to obstructed portal venous flow.

    Science.gov (United States)

    Hayashi, Hiromitsu; Kuroki, Hideyuki; Higashi, Takaaki; Takeyama, Hideaki; Yokoyama, Naomi; Okabe, Hirohisa; Nitta, Hidetoshi; Beppu, Toru; Takamori, Hiroshi; Baba, Hideo

    2017-07-01

    Liver is an amazing organ that can undergo regenerative and atrophic changes inversely, depending on blood flow conditions. Although the regenerative mechanism has been extensively studied, the atrophic mechanism remains to be elucidated. To assess the molecular mechanism of liver atrophy due to reduced portal blood flow, we analyzed the gene expressions between atrophic and hypertrophic livers induced by portal vein embolization in three human liver tissues using microarray analyses. Thrombospondin (TSP)-1 is an extracellular protein and a negative regulator of liver regeneration through its activation of the transforming growth factor-β/Smad signaling pathway. TSP-1 was extracted as the most upregulated gene in atrophic liver compared to hypertrophic liver due to portal flow obstruction in human. Liver atrophic and hypertrophic changes were confirmed by HE and proliferating cell nuclear antigen staining and terminal deoxynucleotidyl transferase-mediated digoxigenin-dUTP nick-end labeling. In an in vivo model with portal ligation, TSP-1 and phosphorylated Smad2 expression were continuously induced at 6 h and thereafter in the portal ligated liver, whereas the induction was transient at 6 h in the portal non-ligated liver. Indeed, while cell proliferation represented by proliferating cell nuclear antigen expression at 48 h was induced in the portal ligated liver, the sinusoidal dilatation and hepatocyte cell death with terminal deoxynucleotidyl transferase-mediated digoxigenin-dUTP nick-end labeling was detectable at 48 h in the portal ligated liver. Obstructed portal flow induces persistent TSP-1 expression and transforming growth factor-β/Smad signal activation in atrophic liver. Thrombospondin-1 may be implicated in the liver atrophic change due to obstructed portal flow as a pro-atrophic factor. © 2016 The Japan Society of Hepatology.

  7. The influence of hypothyroidism on liver regeneration: an experimental study in rats A influência do hipotireoidismo na regeneração hepatica: estudo experimental em ratos

    Directory of Open Access Journals (Sweden)

    Maria de Lourdes Pessole Biondo-Simões

    2007-01-01

    Full Text Available BACKGROUND: The influence of hypothyroidism in liver regeneration has been a controversial opinions. PURPOSE: The aim of this study is to identify the relationship between hypothyroidism and liver regeneration in rats. METHODS: Forty male Wistar rats divided into two groups of 20 specimens each. One group (C consisted of euthyroid rats, and the other (H of hypothyroid rats. All the animals were anesthetized with xylazine and ketamine and subjected to a longitudinal incision in the anterior cervical region. The thyroid was completely resected in group H and left intact in group C. Ten days after the first surgery, both groups of rats were weighed and submitted to partial hepatectomy, in which the left lateral and median lobes were resected and weighed. Examinations were carried out after 24 hours and, on day 7, using 3 methods: KWON et al.'s formula to identify increase in volume; mitotic figure count in five fields; and the percentage of PCNA-positive nuclei in five fields. RESULTS: Using KWON's formula, the regeneration rate for Group C after 24 hours was 58.49% whereas that for Group H was 50.42% (p=0.0165. After 7 days, the regeneration rate for Group C was 93.04% and Group H 93.74% (p=0.2165. The average number of mitotic figures after 24 hours was 14 ± 1.5 for Group C and 9.8 ± 2.2 for Group H (p=0,00016. After 7 days the corresponding figures were 5.4 ± 1.1 and 5.1 ± 1.2 (p=0,6343. The average number of PCNA-positive nuclei after 24 hours was 13.55 ± 3.84 in Group C and 7.7 ± 2.11 in Group H (p =0,0006. The corresponding figures after 7 days were 3.5 ± 2.39 for Group C and 4.11 ± 1.90 for Group H (p>0.05. CONCLUSION: We conclude that hypothyroidism in rats causes a delay in hepatic regeneration in the first 24 hours, but that after seven days the rate of regeneration is equal to that in euthyroid rats.BACKGROUND: A influência do hipotireoidismo na regeneração hepatica tem opiniões controvérsas. OBJETIVO: Identificar a rela

  8. Usage of adenovirus expressing thymidine kinase mediated hepatocellular damage for enabling mouse liver repopulation with allogenic or xenogenic hepatocytes.

    Directory of Open Access Journals (Sweden)

    Daniel Moreno

    Full Text Available It has been shown that the liver of immunodeficient mice can be efficiently repopulated with human hepatocytes when subjected to chronic hepatocellular damage. Mice with such chimeric livers represent useful reagents for medical and clinical studies. However all previously reported models of humanized livers are difficult to implement as they involve cross-breeding of immunodeficient mice with mice exhibiting genetic alterations causing sustained hepatic injury. In this paper we attempted to create chimeric livers by inducing persistent hepatocellular damage in immunodeficient Rag2(-/- γc(-/- mice using an adenovirus encoding herpes virus thymidine kinase (AdTk and two consecutive doses of ganciclovir (GCV. We found that this treatment resulted in hepatocellular damage persisting for at least 10 weeks and enabled efficient engraftment and proliferation within the liver of either human or allogenic hepatocytes. Interestingly, while the nodules generated from the transplanted mouse hepatocytes were well vascularized, the human hepatocytes experienced progressive depolarization and exhibited reduced numbers of murine endothelial cells inside the nodules. In conclusion, AdTk/GCV-induced liver damage licenses the liver of immunodeficient mice for allogenic and xenogenic hepatocyte repopulation. This approach represents a simple alternative strategy for chimeric liver generation using immunodeficient mice without additional genetic manipulation of the germ line.

  9. Impaired TFEB-mediated Lysosome Biogenesis and Autophagy Promote Chronic Ethanol-induced Liver Injury and Steatosis in Mice.

    Science.gov (United States)

    Chao, Xiaojuan; Wang, Shaogui; Zhao, Katrina; Li, Yuan; Williams, Jessica A; Li, Tiangang; Chavan, Hemantkumar; Krishnamurthy, Partha; He, Xi C; Li, Linheng; Ballabio, Andrea; Ni, Hong-Min; Ding, Wen-Xing

    2018-05-18

    Defects in lysosome function and autophagy contribute to pathogenesis of alcoholic liver disease. We investigated the mechanisms by which alcohol consumption affects these processes, evaluating the functions transcription factor EB (TFEB), which regulates lysosomal biogenesis. We performed studies with GFP-LC3 mice, mice with liver-specific deletion of transcription factor EB (TFEB), mice with disruption of the transcription factor E3 gene (TFE3-knockout mice), mice with disruption of the Tefb and Tfe3 genes (TFEB, TFE3 double-knockout mice), and Tfeb flox/flox albumin cre-negative mice (controls). TFEB was overexpressed from adenoviral vectors or knocked down with small interfering RNAs in mouse livers. Mice were placed on diets of chronic ethanol feeding plus an acute binge to induce liver damage (ethanol diet); some mice were also given injections of torin1, an inhibitor of the kinase activity of the mechanistic target of rapamycin (mTOR). Liver tissues were collected and analyzed by immunohistochemistry, immunoblots, and quantitative real-time PCR to monitor lysosome biogenesis. We analyzed levels of TFEB in liver tissues from patients with alcoholic hepatitis and from healthy donors (controls) by immunohistochemistry. Liver tissues from mice on the ethanol diet had lower levels of total and nuclear TFEB, compared with control mice, and hepatocytes had reduced lysosome biogenesis and autophagy. Hepatocytes from mice on the ethanol diet had increased translocation of mTOR into lysosomes, resulting increased mTOR activation. Administration of torin1 increased liver levels of TFEB and reduced steatosis and liver injury induced by ethanol. Mice that overexpressed TFEB in liver developed less-severe ethanol-induced liver injury and had increased lysosomal biogenesis and mitochondrial bioenergetics compared to mice carrying a control vector. Mice with knockdown of TFEB, as well as TFEB, TFE3 double-knockout mice, developed more severe liver injury in response to the

  10. Periodontal regeneration.

    Science.gov (United States)

    Ivanovski, S

    2009-09-01

    The ultimate goal of periodontal therapy is the regeneration of the tissues destroyed as a result of periodontal disease. Currently, two clinical techniques, based on the principles of "guided tissue regeneration" (GTR) or utilization of the biologically active agent "enamel matrix derivative" (EMD), can be used for the regeneration of intrabony and Class II mandibular furcation periodontal defects. In cases where additional support and space-making requirements are necessary, both of these procedures can be combined with a bone replacement graft. There is no evidence that the combined use of GTR and EMD results in superior clinical results compared to the use of each material in isolation. Great variability in clinical outcomes has been reported in relation to the use of both EMD and GTR, and these procedures can be generally considered to be unpredictable. Careful case selection and treatment planning, including consideration of patient, tooth, site and surgical factors, is required in order to optimize the outcomes of treatment. There are limited data available for the clinical effectiveness of other biologically active molecules, such as growth factors and platelet concentrates, and although promising results have been reported, further clinical trials are required in order to confirm their effectiveness. Current active areas of research are centred on tissue engineering and gene therapy strategies which may result in more predictable regenerative outcomes in the future.

  11. PGC-1α in aging and lifelong exercise training-mediated regulation of UPR in mouse liver

    DEFF Research Database (Denmark)

    Maag Kristensen, Caroline; Brandt, Christina Tingbjerg; Jørgensen, Stine Ringholm

    2017-01-01

    of specific UPR pathways and increased activity of the ATF6 pathway in the liver with aging. Lifelong exercise training prevented the age-associated change in BiP and IRE1α protein, but not cleaved ATF6 protein and resulted in further decreased PERK protein. Taken together, the present study provides evidence...... that the capacity and activity of the three UPR pathways are differentially regulated in the liver with aging and lifelong exercise training. In addition, PGC-1α does not seem to regulate the activity of hepatic UPR in response to exercise training, but to influence the capacity of the liver to induce UPR......Aging is associated with changes in several metabolic pathways affecting liver function including the adaptive unfolded protein response (UPR). On the other hand, exercise training has been shown to exert beneficial effects on metabolism in the liver and exercise training has been reported...

  12. Xenosensor CAR mediates down-regulation of miR-122 and up-regulation of miR-122 targets in the liver

    Energy Technology Data Exchange (ETDEWEB)

    Kazantseva, Yuliya A.; Yarushkin, Andrei A.; Mostovich, Lyudmila A. [The Institute of Molecular Biology and Biophysics, Timakova str., 2/12, Novosibirsk 630117 (Russian Federation); Pustylnyak, Yuliya A. [Novosibirsk State University, Pirogova str., 2, Novosibirsk 630090 (Russian Federation); Pustylnyak, Vladimir O., E-mail: pustylnyak@ngs.ru [The Institute of Molecular Biology and Biophysics, Timakova str., 2/12, Novosibirsk 630117 (Russian Federation); Novosibirsk State University, Pirogova str., 2, Novosibirsk 630090 (Russian Federation); The Institute International Tomography Center of the Russian Academy of Sciences, Institutskaya str. 3-A, Novosibirsk 630090 (Russian Federation)

    2015-10-01

    MiR-122 is a major hepatic microRNA, accounting for more than 70% of the total liver miRNA population. It has been shown that miR-122 is associated with liver diseases, including hepatocellular carcinoma. Mir-122 is an intergenic miRNA with its own promoter. Pri-miR-122 expression is regulated by liver-enriched transcription factors, mainly by HNF4α, which mediates the expression via the interaction with a specific DR1 site. It has been shown that phenobarbital-mediated activation of constitutive androstane receptor (CAR), xenobiotic nuclear receptor, is associated with a decrease in miR-122 in the liver. In the present study, we investigated HNF4α–CAR cross-talk in the regulation of miR-122 levels and promitogenic signalling in mouse livers. The level of miR-122 was significantly repressed by treatment with 1,4-bis[2-(3,5-dichloropyridyloxy)]benzene (TCPOBOP), which is an agonist of mouse CAR. ChIP assays demonstrated that TCPOBOP-activated CAR inhibited HNF4α transactivation by competing with HNF4α for binding to the DR1 site in the pri-miR-122 promoter. Such transcription factor replacement was strongly correlated with miR-122 down-regulation. Additionally, the decrease in miR-122 levels produced by CAR activation is accompanied by an increase in mRNA and cellular protein levels of E2f1 and its accumulation on the target cMyc gene promoter. The increase in accumulation of E2f1 on the target cMyc gene promoter is accompanied by an increase in cMyc levels and transcriptional activity. Thus, our results provide evidence to support the conclusion that CAR activation decreases miR-122 levels through suppression of HNF4α transcriptional activity and indirectly regulates the promitogenic protein cMyc. HNF4α–CAR cross-talk may provide new opportunities for understanding liver diseases and developing more effective therapeutic approaches to better drug treatments. - Highlights: • CAR activation decreased the level of miR-122 in mouse livers. • CAR decreases

  13. Xenosensor CAR mediates down-regulation of miR-122 and up-regulation of miR-122 targets in the liver

    International Nuclear Information System (INIS)

    Kazantseva, Yuliya A.; Yarushkin, Andrei A.; Mostovich, Lyudmila A.; Pustylnyak, Yuliya A.; Pustylnyak, Vladimir O.

    2015-01-01

    MiR-122 is a major hepatic microRNA, accounting for more than 70% of the total liver miRNA population. It has been shown that miR-122 is associated with liver diseases, including hepatocellular carcinoma. Mir-122 is an intergenic miRNA with its own promoter. Pri-miR-122 expression is regulated by liver-enriched transcription factors, mainly by HNF4α, which mediates the expression via the interaction with a specific DR1 site. It has been shown that phenobarbital-mediated activation of constitutive androstane receptor (CAR), xenobiotic nuclear receptor, is associated with a decrease in miR-122 in the liver. In the present study, we investigated HNF4α–CAR cross-talk in the regulation of miR-122 levels and promitogenic signalling in mouse livers. The level of miR-122 was significantly repressed by treatment with 1,4-bis[2-(3,5-dichloropyridyloxy)]benzene (TCPOBOP), which is an agonist of mouse CAR. ChIP assays demonstrated that TCPOBOP-activated CAR inhibited HNF4α transactivation by competing with HNF4α for binding to the DR1 site in the pri-miR-122 promoter. Such transcription factor replacement was strongly correlated with miR-122 down-regulation. Additionally, the decrease in miR-122 levels produced by CAR activation is accompanied by an increase in mRNA and cellular protein levels of E2f1 and its accumulation on the target cMyc gene promoter. The increase in accumulation of E2f1 on the target cMyc gene promoter is accompanied by an increase in cMyc levels and transcriptional activity. Thus, our results provide evidence to support the conclusion that CAR activation decreases miR-122 levels through suppression of HNF4α transcriptional activity and indirectly regulates the promitogenic protein cMyc. HNF4α–CAR cross-talk may provide new opportunities for understanding liver diseases and developing more effective therapeutic approaches to better drug treatments. - Highlights: • CAR activation decreased the level of miR-122 in mouse livers. • CAR decreases

  14. Angiogenesis is inhibitory for mammalian digit regeneration

    Science.gov (United States)

    Yu, Ling; Yan, Mingquan; Simkin, Jennifer; Ketcham, Paulina D.; Leininger, Eric; Han, Manjong

    2014-01-01

    Abstract The regenerating mouse digit tip is a unique model for investigating blastema formation and epimorphic regeneration in mammals. The blastema is characteristically avascular and we previously reported that blastema expression of a known anti‐angiogenic factor gene, Pedf, correlated with a successful regenerative response (Yu, L., Han, M., Yan, M., Lee, E. C., Lee, J. & Muneoka, K. (2010). BMP signaling induces digit regeneration in neonatal mice. Development, 137, 551–559). Here we show that during regeneration Vegfa transcripts are not detected in the blastema but are expressed at the onset of differentiation. Treating the amputation wound with vascular endothelial growth factor enhances angiogenesis but inhibits regeneration. We next tested bone morphogenetic protein 9 (BMP9), another known mediator of angiogenesis, and found that BMP9 is also a potent inhibitor of digit tip regeneration. BMP9 induces Vegfa expression in the digit stump suggesting that regenerative failure is mediated by enhanced angiogenesis. Finally, we show that BMP9 inhibition of regeneration is completely rescued by treatment with pigment epithelium‐derived factor. These studies show that precocious angiogenesis is inhibitory for regeneration, and provide compelling evidence that the regulation of angiogenesis is a critical factor in designing therapies aimed at stimulating mammalian regeneration. PMID:27499862

  15. Enzymatic, urease-mediated mineralization of gellan gum hydrogel with calcium carbonate, magnesium-enriched calcium carbonate and magnesium carbonate for bone regeneration applications

    DEFF Research Database (Denmark)

    Douglas, Timothy E L; Łapa, Agata; Samal, Sangram Keshari

    2017-01-01

    enzymatically with CaCO3 , Mg-enriched CaCO3 and magnesium carbonate to generate composite biomaterials for bone regeneration. Hydrogels loaded with the enzyme urease were mineralized by incubation in mineralization media containing urea and different ratios of calcium and magnesium ions. Increasing...

  16. Lentiviral-mediated expression of polysialic acid in spinal cord and conditioning lesion promote regeneration of sensory axons into spinal cord

    NARCIS (Netherlands)

    Zhang, Yi; Zhang, Xinyu; Wu, Dongsheng; Verhaagen, J.; Richardson, Peter M; Yeh, John; Bo, Xuenong

    2007-01-01

    In adult mammals, sensory axons that regenerate in the dorsal root are unable to grow across the dorsal root entry zone (DREZ) into the spinal cord. In this study we examined whether, by inducing expression of polysialic acid (PSA) (a large carbohydrate attached to molecules on the cell surface), in

  17. New function of the myostatin/activin type I receptor (ALK4) as a mediator of muscle atrophy and muscle regeneration.

    NARCIS (Netherlands)

    Pasteuning-Vuhman, S.; Boertje-van der Meulen, J.; van Putten, M.; Overzier, M.; ten Dijke, P; Kiełbasa, S.M.; Arindrarto, W.; Wolterbeek, R.; Lezhnina, K.V.; Ozerov, I.V.; Aliper, A.M.; Hoogaars, W.; Aartsma-Rus, A; Loomans, C.J.

    Skeletal muscle fibrosis and impaired muscle regeneration are major contributors to muscle wasting in Duchenne muscular dystrophy (DMD). Muscle growth is negatively regulated by myostatin (MSTN) and activins. Blockage of these pathways may improve muscle quality and function in DMD. Antisense

  18. Role of nitric oxide and KATP channel in the protective effect mediated by nicorandil in bile duct ligation-induced liver fibrosis in rats.

    Science.gov (United States)

    Mohamed, Yasmin S; Ahmed, Lamiaa A; Salem, Hesham A; Agha, Azza M

    2018-05-01

    Liver fibrosis is one of the most serious conditions affecting patients worldwide. In the present study, the role of nitric oxide and KATP channel was investigated for the first time in the possible protection mediated by nicorandil in bile duct ligation-induced liver fibrosis in rats. Nicorandil (3 mg/kg/day) was given orally 24 h after bile duct ligation for 14 days till the end of the experiment. Nicorandil group showed marked improvement in liver function tests, hepatic oxidative stress and inflammatory markers as well as inducible and endothelial nitric oxide synthase protein expressions. Furthermore, nicorandil administration led to significant decrement of phosphorylated protein kinase C, fibrosis and hepatic stellate cells activation as indicated by decreased alpha smooth muscle actin expression. Oral co-administration of glibenclamide (5 mg/kg/day) (a KATP channel blocker) with nicorandil mostly showed similar improvement though not reaching to that of nicorandil group. However, co-adminstration of L-NAME (15 mg/kg/day) (an inhibitor of nitric oxide synthase) completely abolished the protective effects of nicorandil and produced more or less similar results to that of untreated bile duct ligated group. In conclusion, nicorandil is an effective therapy against the development of bile duct ligation-induced liver fibrosis in rats where nitric oxide plays a more prominent role in the protective effect of nicorandil than KATP channel opening. Copyright © 2018 Elsevier Inc. All rights reserved.

  19. Efeito do omeprazol e do pantoprazol sobre a regeneração hepática após hepatectomia parcial em ratos Effect of omeprazole and pantoprazole on liver regeneration after partial hepatectomy in rats

    Directory of Open Access Journals (Sweden)

    Gustavo Barreto de Melo

    2003-12-01

    Full Text Available OBJETIVO: Avaliar os efeitos do omeprazol e do pantoprazol sobre a regeneração hepática após hepatectomia parcial. MÉTODOS: Cinqüenta e oito ratos Wistar machos foram divididos em 4 grupos: Grupo SHAM, Grupo HP, Grupo PANTO e Grupo OMEP. Eles foram submetidos a hepatectomia parcial de 67% (Grupos HP, PANTO e OMEP ou laparotomia (Grupo SHAM. Os fígados foram removidos 32 e 56 horas após a operação. Depois, os animais foram sacrificados. Em todos os grupos, as substâncias (solução salina, omeprazol e pantoprazol foram aplicadas diariamente a partir do momento em que foram operados até o sacrifício. RESULTADOS: O índice de mitose no Grupo SHAM não foi significativo. Trinta e duas horas após a hepatectomia, a contagem de mitoses foi de 1,2 ± 1,09 para o Grupo HP, 1,2 ± 1,6 para o Grupo OMEP e 2,6 ± 3,2 para o Grupo PANTO. Na análise após 56 horas, os valores foram 1,6 ± 0,89 para o HP, 2 ± 1,8 para o OMEP e 2,6 ± 0,54 para o PANTO. Esses resultados não foram estatisticamente significativos. CONCLUSÃO: O omeprazol e o pantoprazol, agentes inibidores da bomba de prótons (H+, K+-ATPase, não interferem na regeneração hepática 32 e 56 horas após hepatectomia parcial a 67% em ratos.PURPOSE: To assess the effects of omeprazole and pantoprazole on liver regeneration after partial hepatectomy. METHODS: Fifty eight male Wistar rats were divided into 4 groups: SHAM, HP, PANTO and OMEP Groups. They were submitted to 67% partial hepatectomy (HP, PANTO and OMEP Groups or laparotomy (SHAM Group. Their livers were removed 32 and 56 hours after the operation. Then, the animals were sacrificed. In all groups, the substances (saline solution, omeprazole and pantoprazole were injected once daily from the moment they were operated on until the time of sacrifice. RESULTS: In SHAM Group the mitotic index was not significant. Thirty two hours after hepatectomy, the mitosis index was 1.2 ± 1.09 in HP Group, 1.2 ± 1.6 in OMEP Group and 2

  20. New therapeutic strategies for canine liver disease; Growth factors and liver progenitor cells

    NARCIS (Netherlands)

    Arends, B.

    2008-01-01

    The liver has the unique capacity to regulate its mass after loss of functional liver cells due to liver disease, injury, and/or toxicity. Unfortunately, in the course of chronic liver disease this meticulously regulated regeneration process is imbalanced resulting in a decreased regenerative

  1. Adipokines, inflammatory mediators, and insulin-resistance parameters may not be good markers of metabolic syndrome after liver transplant.

    Science.gov (United States)

    Anastácio, Lucilene Rezende; de Oliveira, Marina Chaves; Diniz, Kiara Gonçalves; Ferreira, Adaliene Matos Versiane; Lima, Agnaldo Soares; Correia, Maria Isabel Toulson Davisson; Vilela, Eduardo Garcia

    2016-09-01

    The role of adipokines in liver transplantation (LTx) recipients who have metabolic syndrome (MetS) has seldom been assessed. The aim of this study was to investigate the concentrations of adipokines, inflammatory mediators, and insulin-resistance markers in liver recipients with MetS and its components. Serum samples from 34 patients (55.9% male; 54.9 ± 13.9 y; 7.7 ± 2.9 y after LTx; 50% presented with MetS) were assessed for adiponectin, resistin, tumor necrosis factor (TNF)-α, monocyte chemoattractant protein (MCP)-1, interleukin (IL)-6, C-reactive protein (CRP), homeostatic model assessment-insulin resistance (HOMA-IR) and free fatty acid (FFA) levels. The dosages were uni- and multivariate analyzed to cover MetS (using the Harmonizing MetS criteria), its components, and dietary intake. A higher concentration of adiponectin (P < 0.05) was observed among patients with MetS (5.2 ± 3.2 μg/mL) compared with those without MetS (3.2 ± 1.2 μg/mL), as well as those with MetS components versus those without them: abdominal obesity (4.6 ± 2.6 μg/mL versus 2.6 ± 0.6 μg/mL), high triacylglycerols (TGs; 5.6 ± 3.1 μg/mL versus 3 ± 0.9 μg/mL) and low high-density lipoprotein (HDL; 6.1 ± 2.7 μg/mL versus 3.3 ± 1.9 μg/mL). Increased TNF-α and HOMA-IR values were seen in patients with abdominal obesity. Patients with high TGs also had greater FFA values. Independent predictors for adiponectin were waist-to-hip ratio, low HDL and high TGs. High TGs and fasting blood glucose were independent predictors for HOMA-IR. Independent predictors could not be identified for CRP, TNF-α, MCP-1, IL-6, or FFA. MetS and its components are related to an increased HOMA-IR concentration and FFA. Adiponectin, resistin, and inflammatory markers, such as TNF-α, IL-6, MCP-1, and CRP, were not associated with MetS in this sample of post-LTx patients. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Proteinase activated receptor 1 mediated fibrosis in a mouse model of liver injury: a role for bone marrow derived macrophages.

    Directory of Open Access Journals (Sweden)

    Yiannis N Kallis

    Full Text Available Liver fibrosis results from the co-ordinated actions of myofibroblasts and macrophages, a proportion of which are of bone marrow origin. The functional effect of such bone marrow-derived cells on liver fibrosis is unclear. We examine whether changing bone marrow genotype can down-regulate the liver's fibrotic response to injury and investigate mechanisms involved. Proteinase activated receptor 1 (PAR1 is up-regulated in fibrotic liver disease in humans, and deficiency of PAR1 is associated with reduced liver fibrosis in rodent models. In this study, recipient mice received bone marrow transplantation from PAR1-deficient or wild-type donors prior to carbon tetrachloride-induced liver fibrosis. Bone marrow transplantation alone from PAR1-deficient mice was able to confer significant reductions in hepatic collagen content and activated myofibroblast expansion on wild-type recipients. This effect was associated with a decrease in hepatic scar-associated macrophages and a reduction in macrophage recruitment from the bone marrow. In vitro, PAR1 signalling on bone marrow-derived macrophages directly induced their chemotaxis but did not stimulate proliferation. These data suggest that the bone marrow can modulate the fibrotic response of the liver to recurrent injury. PAR1 signalling can contribute to this response by mechanisms that include the regulation of macrophage recruitment.

  3. Regeneration of Optic Nerve

    Directory of Open Access Journals (Sweden)

    Kwok-Fai So

    2011-05-01

    Full Text Available The optic nerve is part of the central nervous system (CNS and has a structure similar to other CNS tracts. The axons that form the optic nerve originate in the ganglion cell layer of the retina and extend through the optic tract. As a tissue, the optic nerve has the same organization as the white matter of the brain in regard to its glia. There are three types of glial cells: Oligodendrocytes, astrocytes, and microglia. Little structural and functional regeneration of the CNS takes place spontaneously following injury in adult mammals. In contrast, the ability of the mammalian peripheral nervous system (PNS to regenerate axons after injury is well documented. A number of factors are involved in the lack of CNS regeneration, including: (i the response of neuronal cell bodies against the damage; (ii myelin-mediated inhibition by oligodendrocytes; (iii glial scarring, by astrocytes; (iv macrophage infiltration; and (v insufficient trophic factor support. The fundamental difference in the regenerative capacity between CNS and PNS neuronal cell bodies has been the subject of intensive research. In the CNS the target normally conveys a retrograde trophic signal to the cell body. CNS neurons die because of trophic deprivation. Damage to the optic nerve disconnects the neuronal cell body from its target-derived trophic peptides, leading to the death of retinal ganglion cells. Furthermore, the axontomized neurons become less responsive to the peptide trophic signals they do receive. On the other hand, adult PNS neurons are intrinsically responsive to neurotrophic factors and do not lose trophic responsiveness after axotomy. In this talk different strategies to promote optic-nerve regeneration in adult mammals are reviewed. Much work is still needed to resolve many issues. This is a very important area of neuroregeneration and neuroprotection, as currently there is no cure after traumatic optic nerve injury or retinal disease such as glaucoma, which

  4. Overexpression of Heparin-Binding Epidermal Growth Factor-Like Growth Factor Mediates Liver Fibrosis in Transgenic Mice.

    Science.gov (United States)

    Guo, Yongze; Ding, Qian; Chen, Lei; Ji, Chenguang; Hao, Huiyao; Wang, Jia; Qi, Wei; Xie, Xiaoli; Ma, Junji; Li, Aidi; Jiang, Xiaoyu; Li, Xiaotian; Jiang, Huiqing

    2017-08-01

    The role of heparin-binding epidermal growth factor-like growth factor (HB-EGF) in liver fibrosis is not clear and is sometimes even contradictory. To clarify this role, a HB-EGF transgenic (Tg) mouse model was, for the first time, used to evaluate the functions of HB-EGF in liver fibrosis. For the in vivo study, carbon tetrachloride injection and bile duct ligation treatment were used to induce liver fibrosis in HB-EGF Tg mice and wild-type (WT) mice, respectively. Primary hepatic satellite cells (HSCs) were isolated from HB-EGF Tg and WT mice for the in vitro study. Compared with the WT mice, HB-EGF Tg mice were shown to develop more severe liver fibrosis when treated with carbon tetrachloride or bile duct ligation, with increased matrix metalloproteinases 13 activity and enhanced expression of fibrogenic genes including α-smooth muscle actin and collagen I. HB-EGF gene transfer led to an increase in proliferation and a decrease in apoptosis in primary HSCs. The ERK signaling pathway was more highly activated in primary HSCs from HB-EGF Tg mice than in those from WT mice. Our investigation confirmed the profibrotic effect of HB-EGF on the liver using a Tg mouse model. This result may contribute to the elucidation of HB-EGF as a therapeutic target in liver fibrosis. Copyright © 2017 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.

  5. Zingerone suppresses liver inflammation induced by antibiotic mediated endotoxemia through down regulating hepatic mRNA expression of inflammatory markers in Pseudomonas aeruginosa peritonitis mouse model.

    Directory of Open Access Journals (Sweden)

    Lokender Kumar

    Full Text Available Antibiotic-induced endotoxin release is associated with high mortality rate even when appropriate antibiotics are used for the treatment of severe infections in intensive care units. Since liver is involved in systemic clearance and detoxification of endotoxin hence it becomes a primary target organ for endotoxin mediated inflammation. Currently available anti-inflammatory drugs give rise to serious side effects. Hence, there is an urgent need for safe and effective anti-inflammatory therapy. It is likely that anti-inflammatory phytochemicals and neutraceutical agents may have the potential to reduce the endotoxin mediated inflammation and complications associated with endotoxin release. Keeping this in mind, the present study was planned to evaluate the hepatoprotective potential of zingerone (active compound of zingiber officinale against liver inflammation induced by antibiotic mediated endotoxemia. The selected antibiotics capable of releasing high content of endotoxin were employed for their in vivo efficacy in P.aeruginosa peritonitis model. Released endotoxin induced inflammation and zingerone as co-anti-inflammatory therapy significantly reduced inflammatory response. Improved liver histology and reduced inflammatory markers MDA, RNI, MPO, tissue damage markers (AST, ALT, ALP and inflammatory cytokines (MIP-2, IL-6 and TNF-α were indicative of therapeutic potential of zingerone. The mechanism of action of zingerone may be related to significant inhibition of the mRNA expression of inflammatory markers (TLR4, RelA, NF-kB2, TNF- α, iNOS, COX-2 indicating that zingerone interferes with cell signalling pathway and suppresses hyper expression of cell signaling molecules of inflammatory pathway. Zingerone therapy significantly protected liver from endotoxin induced inflammatory damage by down regulating biochemical as well as molecular markers of inflammation. In conclusion, this study provides evidence that zingerone is a potent anti

  6. Zingerone suppresses liver inflammation induced by antibiotic mediated endotoxemia through down regulating hepatic mRNA expression of inflammatory markers in Pseudomonas aeruginosa peritonitis mouse model.

    Science.gov (United States)

    Kumar, Lokender; Chhibber, Sanjay; Harjai, Kusum

    2014-01-01

    Antibiotic-induced endotoxin release is associated with high mortality rate even when appropriate antibiotics are used for the treatment of severe infections in intensive care units. Since liver is involved in systemic clearance and detoxification of endotoxin hence it becomes a primary target organ for endotoxin mediated inflammation. Currently available anti-inflammatory drugs give rise to serious side effects. Hence, there is an urgent need for safe and effective anti-inflammatory therapy. It is likely that anti-inflammatory phytochemicals and neutraceutical agents may have the potential to reduce the endotoxin mediated inflammation and complications associated with endotoxin release. Keeping this in mind, the present study was planned to evaluate the hepatoprotective potential of zingerone (active compound of zingiber officinale) against liver inflammation induced by antibiotic mediated endotoxemia. The selected antibiotics capable of releasing high content of endotoxin were employed for their in vivo efficacy in P.aeruginosa peritonitis model. Released endotoxin induced inflammation and zingerone as co-anti-inflammatory therapy significantly reduced inflammatory response. Improved liver histology and reduced inflammatory markers MDA, RNI, MPO, tissue damage markers (AST, ALT, ALP) and inflammatory cytokines (MIP-2, IL-6 and TNF-α) were indicative of therapeutic potential of zingerone. The mechanism of action of zingerone may be related to significant inhibition of the mRNA expression of inflammatory markers (TLR4, RelA, NF-kB2, TNF- α, iNOS, COX-2) indicating that zingerone interferes with cell signalling pathway and suppresses hyper expression of cell signaling molecules of inflammatory pathway. Zingerone therapy significantly protected liver from endotoxin induced inflammatory damage by down regulating biochemical as well as molecular markers of inflammation. In conclusion, this study provides evidence that zingerone is a potent anti

  7. The Role of Butylidenephthalide in Targeting Microenvironment Contributes to the Ameliorate of Liver Fibrosis

    Directory of Open Access Journals (Sweden)

    Hong-Meng eChuang

    2016-04-01

    Full Text Available The treatment of liver fibrosis has clinical limitations because of its multiple etiologies, such as epithelial–mesenchymal transition (EMT promotion, cell regeneration and remodeling dysfunction, inflammatory cell activation, and scar tissue deposition. These factors might be considered as a new target for the fibrotic microenvironment, leading to increased fibrogenesis and liver fibrosis. Here, we investigate a small molecule named butylidenephthalide (BP and its multiple effects on liver fibrosis treatment. Thioacetamide was used in vivo to induce chronic liver fibrosis. BP was administered orally in rats for a period of 2 weeks and 4 weeks, which resulted in a significantly reduced fibrosis score (p<0.05 and (p<0.001, respectively. The inflammatory reaction of macrophage infiltration were reduced in the administration of BP, which led to the decrease in the transaminase levels. Moreover, we also found liver functions recovering (due to the increased serum albumin and reduced prothrombin time where liver cells regenerated, which can be seen in the increase of Ki-67 on Oval cell. In addition, the fibrotic scar was also reduced, along with the expression of matrix metalloprotease by hepatic stellate cell. Furthermore, regarding the mechanism/study of EMT reduced by BP, the knockdown of BMP-7, which could reduce α-SMA expression, was mediated by the regulation of TGF-β, which implies its major role on EMT. Finally, in the in vivo study, BP treatment of liver fibrosis was reduced by Bmp7 knockdown in zebrafish, suggesting that BP leads to the reduction of liver fibrosis, which also depends on BMP-7 induction. These results suggest that BP had multiple targets for treating liver fibrosis in the following ways: reduction of EMT, decreasing inflammatory reaction, and liver cell proliferation. This multiple targets approach provided a new mechanism to treat liver injury and fibrosis.

  8. Liver transplant

    Science.gov (United States)

    Hepatic transplant; Transplant - liver; Orthotopic liver transplant; Liver failure - liver transplant; Cirrhosis - liver transplant ... The donated liver may be from: A donor who has recently died and has not had liver injury. This type of ...

  9. Enzymatic, urease-mediated mineralization of gellan gum hydrogel with calcium carbonate, magnesium-enriched calcium carbonate and magnesium carbonate for bone regeneration applications.

    Science.gov (United States)

    Douglas, Timothy E L; Łapa, Agata; Samal, Sangram Keshari; Declercq, Heidi A; Schaubroeck, David; Mendes, Ana C; der Voort, Pascal Van; Dokupil, Agnieszka; Plis, Agnieszka; De Schamphelaere, Karel; Chronakis, Ioannis S; Pamuła, Elżbieta; Skirtach, Andre G

    2017-12-01

    Mineralization of hydrogel biomaterials is considered desirable to improve their suitability as materials for bone regeneration. Calcium carbonate (CaCO 3 ) has been successfully applied as a bone regeneration material, but hydrogel-CaCO 3 composites have received less attention. Magnesium (Mg) has been used as a component of calcium phosphate biomaterials to stimulate bone-forming cell adhesion and proliferation and bone regeneration in vivo, but its effect as a component of carbonate-based biomaterials remains uninvestigated. In the present study, gellan gum (GG) hydrogels were mineralized enzymatically with CaCO 3 , Mg-enriched CaCO 3 and magnesium carbonate to generate composite biomaterials for bone regeneration. Hydrogels loaded with the enzyme urease were mineralized by incubation in mineralization media containing urea and different ratios of calcium and magnesium ions. Increasing the magnesium concentration decreased mineral crystallinity. At low magnesium concentrations calcite was formed, while at higher concentrations magnesian calcite was formed. Hydromagnesite (Mg 5 (CO 3 ) 4 (OH) 2 .4H 2 O) formed at high magnesium concentration in the absence of calcium. The amount of mineral formed and compressive strength decreased with increasing magnesium concentration in the mineralization medium. The calcium:magnesium elemental ratio in the mineral formed was higher than in the respective mineralization media. Mineralization of hydrogels with calcite or magnesian calcite promoted adhesion and growth of osteoblast-like cells. Hydrogels mineralized with hydromagnesite displayed higher cytotoxicity. In conclusion, enzymatic mineralization of GG hydrogels with CaCO 3 in the form of calcite successfully reinforced hydrogels and promoted osteoblast-like cell adhesion and growth, but magnesium enrichment had no definitive positive effect. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  10. A novel comparative pattern count analysis reveals a chronic ethanol-induced dynamic shift in immediate early NF-κB genome-wide promoter binding during liver regeneration.

    Science.gov (United States)

    Kuttippurathu, Lakshmi; Patra, Biswanath; Hoek, Jan B; Vadigepalli, Rajanikanth

    2016-03-01

    Liver regeneration after partial hepatectomy is a clinically important process that is impaired by adaptation to chronic alcohol intake. We focused on the initial time points following partial hepatectomy (PHx) to analyze the genome-wide binding activity of NF-κB, a key immediate early regulator. We investigated the effect of chronic alcohol intake on immediate early NF-κB genome-wide localization, in the adapted state as well as in response to partial hepatectomy, using chromatin immunoprecipitation followed by promoter microarray analysis. We found many ethanol-specific NF-κB binding target promoters in the ethanol-adapted state, corresponding to the regulation of biosynthetic processes, oxidation-reduction and apoptosis. Partial hepatectomy induced a diet-independent shift in NF-κB binding loci relative to the transcription start sites. We employed a novel pattern count analysis to exhaustively enumerate and compare the number of promoters corresponding to the temporal binding patterns in ethanol and pair-fed control groups. The highest pattern count corresponded to promoters with NF-κB binding exclusively in the ethanol group at 1 h post PHx. This set was associated with the regulation of cell death, response to oxidative stress, histone modification, mitochondrial function, and metabolic processes. Integration with the global gene expression profiles to identify putative transcriptional consequences of NF-κB binding patterns revealed that several of ethanol-specific 1 h binding targets showed ethanol-specific differential expression through 6 h post PHx. Motif analysis yielded co-incident binding loci for STAT3, AP-1, CREB, C/EBP-β, PPAR-γ and C/EBP-α, likely participating in co-regulatory modules with NF-κB in shaping the immediate early response to PHx. We conclude that adaptation to chronic ethanol intake disrupts the NF-κB promoter binding landscape with consequences for the immediate early gene regulatory response to the acute challenge of PHx.

  11. Inhibition of oxidative stress-elicited AKT activation facilitates PPARγ agonist-mediated inhibition of stem cell character and tumor growth of liver cancer cells.

    Directory of Open Access Journals (Sweden)

    Lanlan Liu

    Full Text Available Emerging evidence suggests that tumor-initiating cells (TICs are the most malignant cell subpopulation in tumors because of their resistance to chemotherapy or radiation treatment. Targeting TICs may be a key innovation for cancer treatment. In this study, we found that PPARγ agonists inhibited the cancer stem cell-like phenotype and attenuated tumor growth of human hepatocellular carcinoma (HCC cells. Reactive oxygen species (ROS initiated by NOX2 upregulation were partially responsible for the inhibitory effects mediated by PPARγ agonists. However, PPARγ agonist-mediated ROS production significantly activated AKT, which in turn promoted TIC survival by limiting ROS generation. Inhibition of AKT, by either pharmacological inhibitors or AKT siRNA, significantly enhanced PPARγ agonist-mediated inhibition of cell proliferation and stem cell-like properties in HCC cells. Importantly, in nude mice inoculated with HCC Huh7 cells, we demonstrated a synergistic inhibitory effect of the PPARγ agonist rosiglitazone and the AKT inhibitor triciribine on tumor growth. In conclusion, we observed a negative feedback loop between oxidative stress and AKT hyperactivation in PPARγ agonist-mediated suppressive effects on HCCs. Combinatory application of an AKT inhibitor and a PPARγ agonist may provide a new strategy for inhibition of stem cell-like properties in HCCs and treatment of liver cancer.

  12. Cardiomyocyte Regeneration

    Directory of Open Access Journals (Sweden)

    Toshio Nakanishi

    2013-01-01

    Full Text Available The heart was initially believed to be a terminally differentiated organ; once the cardiomyocytes died, no recovery could be made to replace the dead cells. However, around a decade ago, the concept of cardiac stem cells (CSCs in adult hearts was proposed. CSCs differentiate into cardiomyocytes, keeping the heart functioning. Studies have proved the existence of stem cells in the heart. These somatic stem cells have been studied for use in cardiac regeneration. Moreover, recently, induced pluripotent stem cells (iPSCs were invented, and methodologies have now been developed to induce stable cardiomyocyte differentiation and purification of mature cardiomyocytes. A reprogramming method has also been applied to direct reprogramming using cardiac fibroblasts into cardiomyocytes. Here, we address cardiomyocyte differentiation of CSCs and iPSCs. Furthermore, we describe the potential of CSCs in regenerative biology and regenerative medicine.

  13. Heart regeneration.

    Science.gov (United States)

    Breckwoldt, Kaja; Weinberger, Florian; Eschenhagen, Thomas

    2016-07-01

    Regenerating an injured heart holds great promise for millions of patients suffering from heart diseases. Since the human heart has very limited regenerative capacity, this is a challenging task. Numerous strategies aiming to improve heart function have been developed. In this review we focus on approaches intending to replace damaged heart muscle by new cardiomyocytes. Different strategies for the production of cardiomyocytes from human embryonic stem cells or human induced pluripotent stem cells, by direct reprogramming and induction of cardiomyocyte proliferation are discussed regarding their therapeutic potential and respective advantages and disadvantages. Furthermore, different methods for the transplantation of pluripotent stem cell-derived cardiomyocytes are described and their clinical perspectives are discussed. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Integration of Developmental and Environmental Cues in the Heart edited by Marcus Schaub and Hughes Abriel. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Reversal of Liver Fibrosis in Chronic Murine Schistosomiasis ...

    African Journals Online (AJOL)

    In schistosomiasis, healing of parasite egg- induced liver ... greater in liver than in other tissues. It has been reported that ..... biology, diseases, and potentials for therapy. Annul Rev Biochem ... regeneration in cirrhotic rats. J Hepatol, 2002;.

  15. Phenobarbital mediates an epigenetic switch at the constitutive androstane receptor (CAR target gene Cyp2b10 in the liver of B6C3F1 mice.

    Directory of Open Access Journals (Sweden)

    Harri Lempiäinen

    2011-03-01

    Full Text Available Evidence suggests that epigenetic perturbations are involved in the adverse effects associated with some drugs and toxicants, including certain classes of non-genotoxic carcinogens. Such epigenetic changes (altered DNA methylation and covalent histone modifications may take place at the earliest stages of carcinogenesis and their identification holds great promise for biomedical research. Here, we evaluate the sensitivity and specificity of genome-wide epigenomic and transcriptomic profiling in phenobarbital (PB-treated B6C3F1 mice, a well-characterized rodent model of non-genotoxic liver carcinogenesis. Methylated DNA Immunoprecipitation (MeDIP-coupled microarray profiling of 17,967 promoter regions and 4,566 intergenic CpG islands was combined with genome-wide mRNA expression profiling to identify liver tissue-specific PB-mediated DNA methylation and transcriptional alterations. Only a limited number of significant anti-correlations were observed between PB-induced transcriptional and promoter-based DNA methylation perturbations. However, the constitutive androstane receptor (CAR target gene Cyp2b10 was found to be concomitantly hypomethylated and transcriptionally activated in a liver tissue-specific manner following PB treatment. Furthermore, analysis of active and repressive histone modifications using chromatin immunoprecipitation revealed a strong PB-mediated epigenetic switch at the Cyp2b10 promoter. Our data reveal that PB-induced transcriptional perturbations are not generally associated with broad changes in the DNA methylation status at proximal promoters and suggest that the drug-inducible CAR pathway regulates an epigenetic switch from repressive to active chromatin at the target gene Cyp2b10. This study demonstrates the utility of integrated epigenomic and transcriptomic profiling for elucidating early mechanisms and biomarkers of non-genotoxic carcinogenesis.

  16. Phenobarbital mediates an epigenetic switch at the constitutive androstane receptor (CAR) target gene Cyp2b10 in the liver of B6C3F1 mice.

    Science.gov (United States)

    Lempiäinen, Harri; Müller, Arne; Brasa, Sarah; Teo, Soon-Siong; Roloff, Tim-Christoph; Morawiec, Laurent; Zamurovic, Natasa; Vicart, Axel; Funhoff, Enrico; Couttet, Philippe; Schübeler, Dirk; Grenet, Olivier; Marlowe, Jennifer; Moggs, Jonathan; Terranova, Rémi

    2011-03-24

    Evidence suggests that epigenetic perturbations are involved in the adverse effects associated with some drugs and toxicants, including certain classes of non-genotoxic carcinogens. Such epigenetic changes (altered DNA methylation and covalent histone modifications) may take place at the earliest stages of carcinogenesis and their identification holds great promise for biomedical research. Here, we evaluate the sensitivity and specificity of genome-wide epigenomic and transcriptomic profiling in phenobarbital (PB)-treated B6C3F1 mice, a well-characterized rodent model of non-genotoxic liver carcinogenesis. Methylated DNA Immunoprecipitation (MeDIP)-coupled microarray profiling of 17,967 promoter regions and 4,566 intergenic CpG islands was combined with genome-wide mRNA expression profiling to identify liver tissue-specific PB-mediated DNA methylation and transcriptional alterations. Only a limited number of significant anti-correlations were observed between PB-induced transcriptional and promoter-based DNA methylation perturbations. However, the constitutive androstane receptor (CAR) target gene Cyp2b10 was found to be concomitantly hypomethylated and transcriptionally activated in a liver tissue-specific manner following PB treatment. Furthermore, analysis of active and repressive histone modifications using chromatin immunoprecipitation revealed a strong PB-mediated epigenetic switch at the Cyp2b10 promoter. Our data reveal that PB-induced transcriptional perturbations are not generally associated with broad changes in the DNA methylation status at proximal promoters and suggest that the drug-inducible CAR pathway regulates an epigenetic switch from repressive to active chromatin at the target gene Cyp2b10. This study demonstrates the utility of integrated epigenomic and transcriptomic profiling for elucidating early mechanisms and biomarkers of non-genotoxic carcinogenesis.

  17. Phenobarbital Mediates an Epigenetic Switch at the Constitutive Androstane Receptor (CAR) Target Gene Cyp2b10 in the Liver of B6C3F1 Mice

    Science.gov (United States)

    Brasa, Sarah; Teo, Soon-Siong; Roloff, Tim-Christoph; Morawiec, Laurent; Zamurovic, Natasa; Vicart, Axel; Funhoff, Enrico; Couttet, Philippe; Schübeler, Dirk; Grenet, Olivier; Marlowe, Jennifer; Moggs, Jonathan; Terranova, Rémi

    2011-01-01

    Evidence suggests that epigenetic perturbations are involved in the adverse effects associated with some drugs and toxicants, including certain classes of non-genotoxic carcinogens. Such epigenetic changes (altered DNA methylation and covalent histone modifications) may take place at the earliest stages of carcinogenesis and their identification holds great promise for biomedical research. Here, we evaluate the sensitivity and specificity of genome-wide epigenomic and transcriptomic profiling in phenobarbital (PB)-treated B6C3F1 mice, a well-characterized rodent model of non-genotoxic liver carcinogenesis. Methylated DNA Immunoprecipitation (MeDIP)-coupled microarray profiling of 17,967 promoter regions and 4,566 intergenic CpG islands was combined with genome-wide mRNA expression profiling to identify liver tissue-specific PB-mediated DNA methylation and transcriptional alterations. Only a limited number of significant anti-correlations were observed between PB-induced transcriptional and promoter-based DNA methylation perturbations. However, the constitutive androstane receptor (CAR) target gene Cyp2b10 was found to be concomitantly hypomethylated and transcriptionally activated in a liver tissue-specific manner following PB treatment. Furthermore, analysis of active and repressive histone modifications using chromatin immunoprecipitation revealed a strong PB-mediated epigenetic switch at the Cyp2b10 promoter. Our data reveal that PB-induced transcriptional perturbations are not generally associated with broad changes in the DNA methylation status at proximal promoters and suggest that the drug-inducible CAR pathway regulates an epigenetic switch from repressive to active chromatin at the target gene Cyp2b10. This study demonstrates the utility of integrated epigenomic and transcriptomic profiling for elucidating early mechanisms and biomarkers of non-genotoxic carcinogenesis. PMID:21455306

  18. Regeneration-associated macrophages: a novel approach to boost intrinsic regenerative capacity for axon regeneration

    Directory of Open Access Journals (Sweden)

    Min Jung Kwon

    2016-01-01

    Full Text Available Axons in central nervous system (CNS do not regenerate spontaneously after injuries such as stroke and traumatic spinal cord injury. Both intrinsic and extrinsic factors are responsible for the regeneration failure. Although intensive research efforts have been invested on extrinsic regeneration inhibitors, the extent to which glial inhibitors contribute to the regeneration failure in vivo still remains elusive. Recent experimental evidence has rekindled interests in intrinsic factors for the regulation of regeneration capacity in adult mammals. In this review, we propose that activating macrophages with pro-regenerative molecular signatures could be a novel approach for boosting intrinsic regenerative capacity of CNS neurons. Using a conditioning injury model in which regeneration of central branches of dorsal root ganglia sensory neurons is enhanced by a preceding injury to the peripheral branches, we have demonstrated that perineuronal macrophages surrounding dorsal root ganglia neurons are critically involved in the maintenance of enhanced regeneration capacity. Neuron-derived chemokine (C-C motif ligand 2 (CCL2 seems to mediate neuron-macrophage interactions conveying injury signals to perineuronal macrophages taking on a soley pro-regenerative phenotype, which we designate as regeneration-associated macrophages (RAMs. Manipulation of the CCL2 signaling could boost regeneration potential mimicking the conditioning injury, suggesting that the chemokine-mediated RAM activation could be utilized as a regenerative therapeutic strategy for CNS injuries.

  19. Sustained miRNA-mediated knockdown of mutant AAT with simultaneous augmentation of wild-type AAT has minimal effect on global liver miRNA profiles.

    Science.gov (United States)

    Mueller, Christian; Tang, Qiushi; Gruntman, Alisha; Blomenkamp, Keith; Teckman, Jeffery; Song, Lina; Zamore, Phillip D; Flotte, Terence R

    2012-03-01

    α-1 antitrypsin (AAT) deficiency can exhibit two pathologic states: a lung disease that is primarily due to the loss of AAT's antiprotease function, and a liver disease resulting from a toxic gain-of-function of the PiZ-AAT (Z-AAT) mutant protein. We have developed several recombinant adeno-associated virus (rAAV) vectors that incorporate microRNA (miRNA) sequences targeting the AAT gene while also driving the expression of miRNA-resistant wild-type AAT-PiM (M-AAT) gene, thus achieving concomitant Z-AAT knockdown in the liver and increased expression of M-AAT. Transgenic mice expressing the human PiZ allele treated with dual-function rAAV9 vectors showed that serum PiZ was stably and persistently reduced by an average of 80%. Treated animals showed knockdown of Z-AAT in liver and serum with concomitant increased serum M-AAT as determined by allele-specific enzyme-linked immunosorbent assays (ELISAs). In addition, decreased globular accumulation of misfolded Z-AAT in hepatocytes and a reduction in inflammatory infiltrates in the liver was observed. Results from microarray studies demonstrate that endogenous miRNAs were minimally affected by this treatment. These data suggests that miRNA mediated knockdown does not saturate the miRNA pathway as has been seen with viral vector expression of short hairpin RNAs (shRNAs). This safe dual-therapy approach can be applied to other disorders such as amyotrophic lateral sclerosis, Huntington disease, cerebral ataxia, and optic atrophies.

  20. Matrix metalloproteinase-9-mediated type III collagen degradation as a novel serological biochemical marker for liver fibrogenesis

    DEFF Research Database (Denmark)

    Veidal, Sanne S; Vassiliadis, Efstathios; Barascuk, Natasha

    2010-01-01

    During fibrogenesis in the liver, in which excessive remodelling of the extracellular matrix (ECM) occurs, both the quantity of type III collagen (CO3) and levels of matrix metalloproteinases (MMPs), including MMP-9, increase significantly. MMPs play major roles in ECM remodelling, via...

  1. Expression analysis on 14-3-3 proteins in regenerative liver following partial hepatectomy

    OpenAIRE

    Xue, Deming; Xue, Yang; Niu, Zhipeng; Guo, Xueqiang; Xu, Cunshuan

    2017-01-01

    Abstract 14-3-3 proteins play a vital part in the regulation of cell cycle and apoptosis as signaling integration points. During liver regeneration, the quiescent hepatocytes go through hypertrophy and proliferation to restore liver weight. Therefore, we speculated that 14-3-3 proteins regulate the progression of liver regeneration. In this study, we analyzed the expression patterns of 14-3-3 proteins during liver regeneration of rat to provide an insight into the regenerative mechanism using...

  2. Intra-Articular Injection of Human Meniscus Stem/Progenitor Cells Promotes Meniscus Regeneration and Ameliorates Osteoarthritis Through Stromal Cell-Derived Factor-1/CXCR4-Mediated Homing

    Science.gov (United States)

    Shen, Weiliang; Chen, Jialin; Zhu, Ting; Chen, Longkun; Zhang, Wei; Fang, Zhi; Heng, Boon Chin; Yin, Zi; Chen, Xiao; Ji, Junfeng

    2014-01-01

    Meniscus injury is frequently encountered in clinical practice. Current surgical therapy involving partial or complete meniscectomy relieves pain in the short-term but often leads to osteoarthritis (OA) in the long-term. In this study, we report a new strategy of articular cartilage protection by intra-articular injection of novel human meniscus stem/progenitor cells (hMeSPCs). We found that hMeSPCs displayed both mesenchymal stem cell characteristics and high expression levels of collagen II. In the rat meniscus injury model, hMeSPC transplantation not only led to more neo-tissue formation and better-defined shape but also resulted in more rounded cells and matured extracellular matrix. Stromal cell-derived factor-1 (SDF-1) enhanced the migration of hMeSPCs, whereas AMD3100 abolished the chemotactic effects of SDF-1 on hMeSPCs, both in vitro and in vivo. In an experimental OA model, transplantation of hMeSPCs effectively protected articular cartilage, as evidenced by reduced expression of OA markers such as collagen I, collagen X, and hypoxia-inducible factor 2α but increased expression of collagen II. Our study demonstrated for the first time that intra-articular injection of hMeSPCs enhanced meniscus regeneration through the SDF-1/CXCR4 axis. Our study highlights a new strategy of intra-articular injection of hMeSPCs for meniscus regeneration. PMID:24448516

  3. Bioartificial liver and liver transplantation: new modalities for the treatment of liver failure

    Directory of Open Access Journals (Sweden)

    DING Yitao

    2017-09-01

    Full Text Available The main features of liver failure are extensive necrosis of hepatocytes, rapid disease progression, and poor prognosis, and at present, there are no effective drugs and methods for the treatment of liver failure. This article summarizes four treatment methods for liver failure, i.e., medical treatment, cell transplantation, liver transplantation, and artificial liver support therapy, and elaborates on the existing treatment methods. The current medical treatment regimen should be optimized; cell transplantation has not been used in clinical practice; liver transplantation is the most effective method, but it is limited by donor liver shortage and high costs; artificial liver can effectively remove toxic substances in human body. Therefore, this article puts forward artificial liver as a transition for liver transplantation; artificial liver can buy time for liver regeneration or liver transplantation and prolong patients′ survival time and thus has a promising future. The new treatment modality of bioartificial liver combined with liver transplantation may bring good news to patients with liver failure.

  4. Phenolic extract of Parkia biglobosa fruit pulp stalls aflatoxin B1 – mediated oxidative rout in the liver of male rats

    Directory of Open Access Journals (Sweden)

    Taofeek O. Ajiboye

    Full Text Available The effect of phenolic extract of Parkia biglobosa (Jacq. R. Br. ex G. Don, Fabaceae, pulp on aflatoxin B1 induced oxidative imbalance in rat liver was evaluated. Thirty-five male rats were randomized into seven groups of five animals each. Rats in group A served as control and received vehicle for drug administration (0.5% DMSO once daily at 24 h intervals for six weeks. Rats in groups B, D, E, F and G, received aflatoxin B1 (167 μg/kg body weight in 0.5% DMSO for three weeks, starting from the third week of the experimental period. Rats in Group C received 400 mg/kg bodyweight of the extract for six weeks, while groups D, E and F rats were treated with 100, 200 and 400 mg/kg bodyweight of the extract for six weeks respectively. Group G rats received 100 mg/kg body weight of vitamin C. Aflatoxin B1-mediated decrease in the activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glucose-6-phosphate dehydrogenase were significantly attenuated. Aflatoxin B1 mediated the elevation in malondialdehyde, conjugated dienes, lipid hydroperoxides, protein carbonyl, and significantly lowered DNA fragmentation percentage. Overall, the phenolic extract of P. biglobosa pulp stalls aflatoxin B1-mediated oxidative rout by enhancing antioxidant enzyme activities leading to decreased lipid peroxidation, protein oxidation and DNA fragmentation.

  5. Protective effect of quercetin on high-fat diet-induced non-alcoholic fatty liver disease in mice is mediated by modulating intestinal microbiota imbalance and related gut-liver axis activation.

    Science.gov (United States)

    Porras, David; Nistal, Esther; Martínez-Flórez, Susana; Pisonero-Vaquero, Sandra; Olcoz, José Luis; Jover, Ramiro; González-Gallego, Javier; García-Mediavilla, María Victoria; Sánchez-Campos, Sonia

    2017-01-01

    Gut microbiota is involved in obesity, metabolic syndrome and the progression of nonalcoholic fatty liver disease (NAFLD). It has been recently suggested that the flavonoid quercetin may have the ability to modulate the intestinal microbiota composition, suggesting a prebiotic capacity which highlights a great therapeutic potential in NAFLD. The present study aims to investigate benefits of experimental treatment with quercetin on gut microbial balance and related gut-liver axis activation in a nutritional animal model of NAFLD associated to obesity. C57BL/6J mice were challenged with high fat diet (HFD) supplemented or not with quercetin for 16 weeks. HFD induced obesity, metabolic syndrome and the development of hepatic steatosis as main hepatic histological finding. Increased accumulation of intrahepatic lipids was associated with altered gene expression related to lipid metabolism, as a result of deregulation of their major modulators. Quercetin supplementation decreased insulin resistance and NAFLD activity score, by reducing the intrahepatic lipid accumulation through its ability to modulate lipid metabolism gene expression, cytochrome P450 2E1 (CYP2E1)-dependent lipoperoxidation and related lipotoxicity. Microbiota composition was determined via 16S ribosomal RNA Illumina next-generation sequencing. Metagenomic studies revealed HFD-dependent differences at phylum, class and genus levels leading to dysbiosis, characterized by an increase in Firmicutes/Bacteroidetes ratio and in Gram-negative bacteria, and a dramatically increased detection of Helicobacter genus. Dysbiosis was accompanied by endotoxemia, intestinal barrier dysfunction and gut-liver axis alteration and subsequent inflammatory gene overexpression. Dysbiosis-mediated toll-like receptor 4 (TLR-4)-NF-κB signaling pathway activation was associated with inflammasome initiation response and reticulum stress pathway induction. Quercetin reverted gut microbiota imbalance and related endotoxemia-mediated

  6. Matrix metalloproteinase-9-mediated type III collagen degradation as a novel serological biochemical marker for liver fibrogenesis

    DEFF Research Database (Denmark)

    Veidal, Sanne S; Vassiliadis, Efstathios; Barascuk, Natasha

    2010-01-01

    During fibrogenesis in the liver, in which excessive remodelling of the extracellular matrix (ECM) occurs, both the quantity of type III collagen (CO3) and levels of matrix metalloproteinases (MMPs), including MMP-9, increase significantly. MMPs play major roles in ECM remodelling, via...... their activity in the proteolytic degradation of extracellular macromolecules such as collagens, resulting in the generation of specific cleavage fragments. These neo-epitopes may be used as markers of fibrosis....

  7. Pomegranate protects against arsenic-induced p53-dependent ROS-mediated inflammation and apoptosis in liver cells.

    Science.gov (United States)

    Choudhury, Sreetama; Ghosh, Sayan; Mukherjee, Sudeshna; Gupta, Payal; Bhattacharya, Saurav; Adhikary, Arghya; Chattopadhyay, Sreya

    2016-12-01

    Molecular mechanisms involved in arsenic-induced toxicity are complex and elusive. Liver is one of the most favored organs for arsenic toxicity as methylation of arsenic occurs mostly in the liver. In this study, we have selected a range of environmentally relevant doses of arsenic to examine the basis of arsenic toxicity and the role of pomegranate fruit extract (PFE) in combating it. Male Swiss albino mice exposed to different doses of arsenic presented marked hepatic injury as evident from histological and electron microscopic studies. Increased activities of enzymes alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase and alkaline phosphatase corroborated extensive liver damage. It was further noted that arsenic exposure initiated reactive oxygen species (ROS)-dependent apoptosis in the hepatocytes involving loss of mitochondrial membrane potential. Arsenic significantly increased nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) and nuclear factor-κB (NF-κB), coupled with increase in phosphorylated Iκ-B, possibly as adaptive cellular survival strategies. Arsenic-induced oxidative DNA damage to liver cells culminated in p53 activation and increased expression of p53 targets like miR-34a and Bax. Pomegranate polyphenols are known to possess remarkable antioxidant properties and are capable of protecting normal cells from various stimuli-induced oxidative stress and toxicities. We explored the protective role of PFE in ameliorating arsenic-induced hepatic damage. PFE was shown to reduce ROS generation in hepatocytes, thereby reducing arsenic-induced Nrf2 activation. PFE also inhibited arsenic-induced NF-κB-inflammatory pathway. Data revealed that PFE reversed arsenic-induced hepatotoxicity and apoptosis by modulating the ROS/Nrf2/p53-miR-34a axis. For the first time, we have mapped the possible signaling pathways associated with arsenic-induced hepatotoxicity and its rescue by pomegranate polyphenols. Copyright

  8. Troxerutin protects against 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47)-induced liver inflammation by attenuating oxidative stress-mediated NAD{sup +}-depletion

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zi-Feng [School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221008, Jiangsu Province (China); Key Laboratory for Biotechnology on Medicinal Plants of Jiangsu Province, School of Life Science, Jiangsu Normal University, 101 Shanghai Road, Xuzhou 221116, Jiangsu Province (China); Zhang, Yan-qiu [School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221008, Jiangsu Province (China); Fan, Shao-Hua [Key Laboratory for Biotechnology on Medicinal Plants of Jiangsu Province, School of Life Science, Jiangsu Normal University, 101 Shanghai Road, Xuzhou 221116, Jiangsu Province (China); Zhuang, Juan [School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221008, Jiangsu Province (China); Zheng, Yuan-Lin, E-mail: ylzheng@jsnu.edu.cn [Key Laboratory for Biotechnology on Medicinal Plants of Jiangsu Province, School of Life Science, Jiangsu Normal University, 101 Shanghai Road, Xuzhou 221116, Jiangsu Province (China); Lu, Jun; Wu, Dong-Mei; Shan, Qun; Hu, Bin [Key Laboratory for Biotechnology on Medicinal Plants of Jiangsu Province, School of Life Science, Jiangsu Normal University, 101 Shanghai Road, Xuzhou 221116, Jiangsu Province (China)

    2015-02-11

    Highlights: • BDE-47 promotes liver inflammation by triggering oxidative stress-induced NAD{sup +} depletion. • Troxerutin inhibits BDE-47-induced liver inflammation via its antioxidant properties. • Troxerutin restores NAD{sup +} level and consequently abates SirT1 loss. • Troxerutin represses acetylation of NF-κB p65 (K310) and H3K9. • Troxerutin is a candidate for prevention and therapy of BDE-47-induced hepatotoxicity. - Abstract: Emerging evidence indicates that 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) induces liver injury through enhanced ROS production and lymphocytic infiltration, which may promote a liver inflammatory response. Antioxidants have been reported to attenuate the cellular toxicity associated with polybrominated diphenyl ethers (PBDEs). In this study, we investigated the effect of troxerutin, a trihydroxyethylated derivative of the natural bioflavonoid rutin, on BDE-47-induced liver inflammation and explored the potential mechanisms underlying this effect. Our results showed that NAD{sup +}-depletion was involved in the oxidative stress-mediated liver injury in a BDE-47 treated mouse model, which was confirmed by Vitamin E treatment. Furthermore, our data revealed that troxerutin effectively alleviated liver inflammation by mitigating oxidative stress-mediated NAD{sup +}-depletion in BDE-47 treated mice. Consequently, troxerutin remarkably restored SirT1 protein expression and activity in the livers of BDE-47-treated mice. Mechanistically, troxerutin dramatically repressed the nuclear translocation of NF-κB p65 and the acetylation of NF-κB p65 (Lys 310) and Histone H3 (Lys9) to abate the transcription of inflammatory genes in BDE-47-treated mouse livers. These inhibitory effects of troxerutin were markedly blunted by EX527 (SirT1 inhibitor) treatment. This study provides novel mechanistic insights into the toxicity of BDE-47 and indicates that troxerutin might be used in the prevention and therapy of BDE-47-induced

  9. Further characterization of cadmium uptake by rat liver sinusoidal plasma membrane vesicles as a carrier mediated process

    International Nuclear Information System (INIS)

    Eastman, H.B.; Frazier, J.M.

    1990-01-01

    Previously we have reported that cadmium (Cd) transport by rat hepatic sinusoidal plasma membrane vesicles (SPMV's) occurs by both carrier mediated process and simple diffusion. This study was undertaken in order to further characterize the carrier mediated component of Cd transport as a carrier mediated process. Efflux of Cd from SPMV's was measured by first loading the vesicles with 1 μM Cd, containing 109 Cd (Amersham, 0.25 mCi/ml, carrier free) as a tracer, and then diluting the vesicles 1 to 5 into efflux buffer containing 0.25 M sucrose, 150 mM NaCl and 50 mM Tris/HCl (pH 7.4). Under standard conditions, no efflux of Cd from the vesicles was observed. However, the presence of 4mM CdCl 2 or 4.0% BSA in the efflux buffer was able to release 109 Cd from the vesicles. When the vesicles were lysed with 0.1% Triton X-100, approximately 75% of the internalized Cd could be released from the vesicles. Efflux of Cd from the vesicles was also determined to be a temperature dependent process. At 0 C the efflux of Cd from the vesicles, in the presence of a 4 mM CdCl 2 or 4.0% BSA chase, was blocked. The specificity of the carrier mediated component of Cd transport for Cd was investigated by determining whether other metals could compete for Cd uptake. Zinc was a competitive inhibitor of the carrier mediated component of Cd uptake while calcium had no effect on Cd uptake. Using this system, we have demonstrated that one component of Cd transport exhibits the basic characteristics of a carrier mediated process: saturation, reversibility, specificity and temperature dependence

  10. Low-dose dioxins alter gene expression related to cholesterol biosynthesis, lipogenesis, and glucose metabolism through the aryl hydrocarbon receptor-mediated pathway in mouse liver

    International Nuclear Information System (INIS)

    Sato, Shoko; Shirakawa, Hitoshi; Tomita, Shuhei; Ohsaki, Yusuke; Haketa, Keiichi; Tooi, Osamu; Santo, Noriaki; Tohkin, Masahiro; Furukawa, Yuji; Gonzalez, Frank J.; Komai, Michio

    2008-01-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a common environmental contaminant. TCDD binds and activates the transcription factor aryl hydrocarbon receptor (AHR), leading to adverse biological responses via the alteration of the expression of various AHR target genes. Although small amounts of TCDD are consumed via contaminated daily foodstuffs and environmental exposures, the effects of low-dose TCDD on gene expression in animal tissues have not been clarified, while a number of genes affected by high-dose TCDD were reported. In this study, we comprehensively analyzed gene expression profiles in livers of C57BL/6N mice that were orally administered relatively low doses of TCDD (5, 50, or 500 ng/kg body weight (bw) day -1 ) for 18 days. The hepatic TCDD concentrations, measured by gas chromatography-mass spectrometry, were 1.2, 17, and 1063 pg toxicity equivalent quantity (TEQ)/g, respectively. The mRNA level of the cytochrome P450 CYP1A1 was significantly increased by treatment with only TCDD 500 ng/kg bw day -1 . DNA microarray and quantitative RT-PCR analyses revealed changes in the expression of genes involved in the circadian rhythm, cholesterol biosynthesis, fatty acid synthesis, and glucose metabolism in the liver with at all doses of TCDD employed. However, repression of expression of genes involved in energy metabolism was not observed in the livers of Ahr-null mice that were administered the same dose of TCDD. These results indicate that changes in gene expression by TCDD are mediated by AHR and that exposure to low-dose TCDD could affect energy metabolism via alterations of gene expression

  11. Induction of Nrf2-mediated cellular defenses and alteration of phase I activities as mechanisms of chemoprotective effects of coffee in the liver.

    Science.gov (United States)

    Cavin, C; Marin-Kuan, M; Langouët, S; Bezençon, C; Guignard, G; Verguet, C; Piguet, D; Holzhäuser, D; Cornaz, R; Schilter, B

    2008-04-01

    Coffee consumption has been associated with a significant decrease in the risk of developing chronic diseases such as Parkinson disease, diabetes type-2 and several types of cancers (e.g. colon, liver). In the present study, a coffee-dependent induction of enzymes involved in xenobiotic detoxification processes was observed in rat liver and primary hepatocytes. In addition, coffee was found to induce the mRNA and protein expression of enzymes involved in cellular antioxidant defenses. These inductions were correlated with the activation of the Nrf2 transcription factor as shown using an ARE-reporter luciferase assay. The induction of detoxifying enzymes GSTs and AKR is compatible with a protection against both genotoxicity and cytotoxicity of aflatoxin B1 (AFB1). This hypothesis was confirmed in in vitro and ex vivo test systems, where coffee reduced both AFB1-DNA and protein adducts. Interestingly, coffee was also found to inhibit cytochrome CYP1A1/2, indicating that other mechanisms different from a stimulation of detoxification may also play a significant role in the chemoprotective effects of coffee. Further investigations in either human liver cell line and primary hepatocytes indicated that the chemoprotective effects of coffee against AFB1 genotoxicity are likely to be of relevance for humans. These data strongly suggest that coffee may protect against the adverse effects of AFB1. In addition, the coffee-mediated stimulation of the Nrf2-ARE pathway resulting in increased endogenous defense mechanisms against electrophilic but also oxidative insults further support that coffee may be associated with a protection against various types of chemical stresses.

  12. Liver X receptor alpha mediated genistein induction of human dehydroepiandrosterone sulfotransferase (hSULT2A1) in Hep G2 cells

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yue; Zhang, Shunfen [Department of Physiological Sciences, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK 74078 (United States); Zhou, Tianyan [Department of Pharmaceutics, School of Pharmaceutical Sciences, Peking University Health Science Center, Beijing 100083 (China); Huang, Chaoqun; McLaughlin, Alicia [Department of Physiological Sciences, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK 74078 (United States); Chen, Guangping, E-mail: guangping.chen@okstate.edu [Department of Physiological Sciences, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK 74078 (United States)

    2013-04-15

    Cytosolic sulfotransferases are one of the major families of phase II drug metabolizing enzymes. Sulfotransferase-catalyzed sulfonation regulates hormone activities, metabolizes drugs, detoxifies xenobiotics, and bioactivates carcinogens. Human dehydroepiandrosterone sulfotransferase (hSULT2A1) plays important biological roles by sulfating endogenous hydroxysteroids and exogenous xenobiotics. Genistein, mainly existing in soy food products, is a naturally occurring phytoestrogen with both chemopreventive and chemotherapeutic potential. Our previous studies have shown that genistein significantly induces hSULT2A1 in Hep G2 and Caco-2 cells. In this study, we investigated the roles of liver X receptor (LXRα) in the genistein induction of hSULT2A1. LXRs have been shown to induce expression of mouse Sult2a9 and hSULT2A1 gene. Our results demonstrate that LXRα mediates the genistein induction of hSULT2A1, supported by Western blot analysis results, hSULT2A1 promoter driven luciferase reporter gene assay results, and mRNA interference results. Chromatin immunoprecipitation (ChIP) assay results demonstrate that genistein increase the recruitment of hLXRα binding to the hSULT2A1 promoter. These results suggest that hLXRα plays an important role in the hSULT2A1 gene regulation. The biological functions of phytoestrogens may partially relate to their induction activity toward hydroxysteroid SULT. - Highlights: ► Liver X receptor α mediated genistein induction of hSULT2A1 in Hep G2 cells. ► LXRα and RXRα dimerization further activated this induction. ► Western blot results agreed well with luciferase reporter gene assay results. ► LXRs gene silencing significantly decreased hSULT2A1 expression. ► ChIP analysis suggested that genistein enhances hLXRα binding to the hSULT2A1 promoter.

  13. FGF21 maintains glucose homeostasis by mediating the cross talk between liver and brain during prolonged fasting.

    Science.gov (United States)

    Liang, Qingning; Zhong, Ling; Zhang, Jialiang; Wang, Yu; Bornstein, Stefan R; Triggle, Chris R; Ding, Hong; Lam, Karen S L; Xu, Aimin

    2014-12-01

    Hepatic gluconeogenesis is a main source of blood glucose during prolonged fasting and is orchestrated by endocrine and neural pathways. Here we show that the hepatocyte-secreted hormone fibroblast growth factor 21 (FGF21) induces fasting gluconeogenesis via the brain-liver axis. Prolonged fasting induces activation of the transcription factor peroxisome proliferator-activated receptor α (PPARα) in the liver and subsequent hepatic production of FGF21, which enters into the brain to activate the hypothalamic-pituitary-adrenal (HPA) axis for release of corticosterone, thereby stimulating hepatic gluconeogenesis. Fasted FGF21 knockout (KO) mice exhibit severe hypoglycemia and defective hepatic gluconeogenesis due to impaired activation of the HPA axis and blunted release of corticosterone, a phenotype similar to that observed in PPARα KO mice. By contrast, intracerebroventricular injection of FGF21 reverses fasting hypoglycemia and impairment in hepatic gluconeogenesis by restoring corticosterone production in both FGF21 KO and PPARα KO mice, whereas all these central effects of FGF21 were abrogated by blockage of hypothalamic FGF receptor-1. FGF21 acts directly on the hypothalamic neurons to activate the mitogen-activated protein kinase extracellular signal-related kinase 1/2 (ERK1/2), thereby stimulating the expression of corticotropin-releasing hormone by activation of the transcription factor cAMP response element binding protein. Therefore, FGF21 maintains glucose homeostasis during prolonged fasting by fine tuning the interorgan cross talk between liver and brain. © 2014 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

  14. Guided genetic screen to identify genes essential in the regeneration of hair cells and other tissues.

    Science.gov (United States)

    Pei, Wuhong; Xu, Lisha; Huang, Sunny C; Pettie, Kade; Idol, Jennifer; Rissone, Alberto; Jimenez, Erin; Sinclair, Jason W; Slevin, Claire; Varshney, Gaurav K; Jones, MaryPat; Carrington, Blake; Bishop, Kevin; Huang, Haigen; Sood, Raman; Lin, Shuo; Burgess, Shawn M

    2018-01-01

    Regenerative medicine holds great promise for both degenerative diseases and traumatic tissue injury which represent significant challenges to the health care system. Hearing loss, which affects hundreds of millions of people worldwide, is caused primarily by a permanent loss of the mechanosensory receptors of the inner ear known as hair cells. This failure to regenerate hair cells after loss is limited to mammals, while all other non-mammalian vertebrates tested were able to completely regenerate these mechanosensory receptors after injury. To understand the mechanism of hair cell regeneration and its association with regeneration of other tissues, we performed a guided mutagenesis screen using zebrafish lateral line hair cells as a screening platform to identify genes that are essential for hair cell regeneration, and further investigated how genes essential for hair cell regeneration were involved in the regeneration of other tissues. We created genetic mutations either by retroviral insertion or CRISPR/Cas9 approaches, and developed a high-throughput screening pipeline for analyzing hair cell development and regeneration. We screened 254 gene mutations and identified 7 genes specifically affecting hair cell regeneration. These hair cell regeneration genes fell into distinct and somewhat surprising functional categories. By examining the regeneration of caudal fin and liver, we found these hair cell regeneration genes often also affected other types of tissue regeneration. Therefore, our results demonstrate guided screening is an effective approach to discover regeneration candidates, and hair cell regeneration is associated with other tissue regeneration.

  15. RORα Induces KLF4-Mediated M2 Polarization in the Liver Macrophages that Protect against Nonalcoholic Steatohepatitis

    Directory of Open Access Journals (Sweden)

    Yong-Hyun Han

    2017-07-01

    Full Text Available The regulation of M1/M2 polarization in liver macrophages is closely associated with the progression of nonalcoholic steatohepatitis (NASH; however, the mechanism involved in this process remains unclear. Here, we describe the orphan nuclear receptor retinoic-acid-related orphan receptor α (RORα as a key regulator of M1/M2 polarization in hepatic residential Kupffer cells (KCs and infiltrated monocyte-derived macrophages. RORα enhanced M2 polarization in KCs by inducing the kruppel-like factor 4. M2 polarization was defective in KCs and bone-marrow-derived macrophages of the myeloid-specific RORα null mice, and these mice were susceptible to HFD-induced NASH. We found that IL-10 played an important role in connecting the function of M2 KCs to lipid accumulation and apoptosis in hepatocytes. Importantly, M2 polarization was controlled by a RORα activator, JC1-40, which improved symptoms of NASH. Our results suggest that the M2-promoting effects of RORα in liver macrophages may provide better therapeutic strategies against NASH.

  16. Acrolein Is a Pathogenic Mediator of Alcoholic Liver Disease and the Scavenger Hydralazine Is Protective in MiceSummary

    Directory of Open Access Journals (Sweden)

    Wei-Yang Chen

    2016-09-01

    Full Text Available Background & Aims: Alcoholic liver disease (ALD remains a major cause of morbidity and mortality, with no Food and Drug Administration–approved therapy. Chronic alcohol consumption causes a pro-oxidant environment and increases hepatic lipid peroxidation, with acrolein being the most reactive/toxic by-product. This study investigated the pathogenic role of acrolein in hepatic endoplasmic reticulum (ER stress, steatosis, and injury in experimental ALD, and tested acrolein elimination/scavenging (using hydralazine as a potential therapy in ALD. Methods: In vitro (rat hepatoma H4IIEC cells and in vivo (chronic+binge alcohol feeding in C57Bl/6 mice models were used to examine alcohol-induced acrolein accumulation and consequent hepatic ER stress, apoptosis, and injury. In addition, the potential protective effects of the acrolein scavenger, hydralazine, were examined both in vitro and in vivo. Results: Alcohol consumption/metabolism resulted in hepatic accumulation of acrolein-protein adducts, by up-regulation of cytochrome P4502E1 and alcohol dehydrogenase, and down-regulation of glutathione-s-transferase-P, which metabolizes/detoxifies acrolein. Alcohol-induced acrolein adduct accumulation led to hepatic ER stress, proapoptotic signaling, steatosis, apoptosis, and liver injury; however, ER-protective/adaptive responses were not induced. Notably, direct exposure to acrolein in vitro mimicked the in vivo effects of alcohol, indicating that acrolein mediates the adverse effects of alcohol. Importantly, hydralazine, a known acrolein scavenger, protected against alcohol-induced ER stress and liver injury, both in vitro and in mice. Conclusions: Our study shows the following: (1 alcohol consumption triggers pathologic ER stress without ER adaptation/protection; (2 alcohol-induced acrolein is a potential therapeutic target and pathogenic mediator of hepatic ER stress, cell death, and injury; and (3 removal/clearance of

  17. Liver Transplant

    Science.gov (United States)

    ... Liver Function Tests Clinical Trials Liver Transplant FAQs Medical Terminology Diseases of the Liver Alagille Syndrome Alcohol-Related ... the Liver The Progression of Liver Disease FAQs Medical Terminology HOW YOU CAN HELP Sponsorship Ways to Give ...

  18. Cancer-related aspects of regeneration research: a review

    International Nuclear Information System (INIS)

    Donaldson, D.J.; Mason, J.M.

    1975-01-01

    Tissue regeneration is simply the replacement of lost cells of a tissue by those remaining. Epimorphic regeneration involves dedifferentiation of many tissues and their organization into a blastema which eventually differentiates into the missing part, usually an appendage. A detailed comparison of the cell membrane changes occurring in epimorphic regeneration, tissue regeneration and cancer can contribute to greater understanding of the differences between normal and tumor cells. Further, there is evidence that epimorphic regeneration fields may in some instances suppress tumor induction and control existing tumors. This influence may be mediated by bioelectric fields, which are ubiquitous in nature and appear to control many cellular events. Disruption of these bioelectric fields suppresses epimorphic regeneration and may lead to cancer in mammals, while applied electric fields alter regenerative events and cause tumor regression. Studies on x-radioinduced regeneration suppression in relation to mutagenesis are also reviewed

  19. Dietary Blueberry and Bifidobacteria Attenuate Nonalcoholic Fatty Liver Disease in Rats by Affecting SIRT1-Mediated Signaling Pathway

    Science.gov (United States)

    Ren, Tingting; Huang, Chao; Cheng, Mingliang

    2014-01-01

    NAFLD model rats were established and divided into NAFLD model (MG group), SIRT1 RNAi (SI group), blueberry juice (BJ group), blueberry juice + bifidobacteria (BJB group), blueberry juice + SIRT1 RNAi (BJSI group), and blueberry juice + bifidobacteria + SIRT1 RNAi groups (BJBSI group). A group with normal rats was a control group (CG). BJB group ameliorated NAFLD, which was better than BJ group (P Blueberry juice and bifidobacteria improve NAFLD by activating SIRTI-mediating signaling pathway. PMID:25544867

  20. Pharmacokinetic study of isocorynoxeine metabolites mediated by cytochrome P450 enzymes in rat and human liver microsomes.

    Science.gov (United States)

    Zhao, Lizhu; Zang, Bin; Qi, Wen; Chen, Fangfang; Wang, Haibo; Kano, Yoshihiro; Yuan, Dan

    2016-06-01

    Isocorynoxeine (ICN) is one of the major bioactive tetracyclic oxindole alkaloids found in Uncaria rhynchophylla (Miq.) Jacks. that is widely used for the treatment of hypertension, vascular dementia, and stroke. The present study was undertaken to assess the plasma pharmacokinetic characteristics of major ICN metabolites, and the role of simulated gastric and intestinal fluid (SGF and SIF), human and rat liver microsomes (HLMs and RLMs), and seven recombinant human CYP enzymes in the major metabolic pathway of ICN. A rapid, sensitive and accurate UHPLC/Q-TOF MS method was validated for the simultaneous determination of ICN and its seven metabolites in rat plasma after oral administration of ICN at 40mg/kg. It was found that 18.19-dehydrocorynoxinic acid (DCA) and 5-oxoisocorynoxeinic acid (5-O-ICA) were both key and predominant metabolites, rather than ICN itself, due to the rapid and extensive metabolism of ICN in vivo. The further study indicated that ICN was mainly metabolized in human or rat liver, and CYPs 2C19, 3A4 and 2D6 were the major enzymes responsible for the biotransformation of ICN to DCA and 5-O-ICA in human. These findings are of significance in understanding of the pharmacokinetic nature of tetracyclic oxindole alkaloids, and provide helpful information for the clinical co-administration of the herbal preparations containing U. rhynchophylla with antihypertensive drugs that are mainly metabolized by CYP3A4 and CYP2C19. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Liver Fibrosis: Current Principles of Diagnosis

    Directory of Open Access Journals (Sweden)

    A.K. Duda

    2014-09-01

    Full Text Available Liver fibrosis — a natural consequence of almost all liver diseases of any origin. We are faced with a number of standard stereotype processes that take place in the liver tissue. Mostly it is the processes of chronic inflammation, which oppose the processes of liver tissue regeneration. The basis of imbalance between the processes of fibrosis and regeneration is an accumulation of extracellular matrix. Liver fibrosis in its development leads to liver cirrhosis, hepatocellular carcinoma, and the increase in morbidity rate is observed worldwide. Furthermore, the process is genetically determined, but modifiable factors play an important role in the progression of this disease. Current data indicate the possibility of reversible liver fibrosis.

  2. Overcoming STC2 mediated drug resistance through drug and gene co-delivery by PHB-PDMAEMA cationic polyester in liver cancer cells.

    Science.gov (United States)

    Cheng, Hongwei; Wu, Zhixian; Wu, Caisheng; Wang, Xiaoyuan; Liow, Sing Shy; Li, Zibiao; Wu, Yun-Long

    2018-02-01

    Stanniocalcin 2 (STC2) overexpression in hepatocellular carcinoma (HCC) could lead to poor prognosis, which might be due to its induced P-glycoprotein and Bcl-2 protein expression level increase. P-glycoprotein or membrane pump induced drug efflux and altered prosurvival Bcl-2 expression are key mechanisms for drug resistance leading to failure of chemotherapy in HCC. However, current strategy to overcome both P-glycoprotein and Bcl-2 protein induced drug resistance was rarely reported. In this work, we utilized an amphiphilic poly[(R)-3-hydroxybutyrate] (PHB)-b-poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) cationic polyester to encapsulate chemotherapeutic paclitaxel (PTX) in hydrophobic PHB domain and Bcl-2 convertor Nur77/ΔDBD gene (Nur77 without DNA binding domain for mitochondria localization) by formation of polyplex due to cationic PDMAEMA segment, to effectively inhibit the drug resistant HepG2/STC2 and SMCC7721/STC2 liver cancer cell growth. Thanks to the cationic nanoparticle complex formation ability and high transfection efficiency to express Bcl-2 conversion proteins, PHB-PDMAEMA/PTX@polyplex could partially impair P-glycoprotein induced PTX efflux and activate the apoptotic function of previous prosurvival Bcl-2 protein. This is the pioneer report of cationic amphiphilic polyester PHB-PDMAEMA to codeliver anticancer drug and therapeutic plasmid to overcome both pump and non-pump mediated chemotherapeutic resistance in liver cancer cells, which might be inspiring for the application of polyester in personalized cancer therapy. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Adenovirus-Mediated Delivery of Decoy Hyper Binding Sites Targeting Oncogenic HMGA1 Reduces Pancreatic and Liver Cancer Cell Viability.

    Science.gov (United States)

    Hassan, Faizule; Ni, Shuisong; Arnett, Tyler C; McKell, Melanie C; Kennedy, Michael A

    2018-03-30

    High mobility group AT-hook 1 (HMGA1) protein is an oncogenic architectural transcription factor that plays an essential role in early development, but it is also implicated in many human cancers. Elevated levels of HMGA1 in cancer cells cause misregulation of gene expression and are associated with increased cancer cell proliferation and increased chemotherapy resistance. We have devised a strategy of using engineered viruses to deliver decoy hyper binding sites for HMGA1 to the nucleus of cancer cells with the goal of sequestering excess HMGA1 at the decoy hyper binding sites due to binding competition. Sequestration of excess HMGA1 at the decoy binding sites is intended to reduce HMGA1 binding at the naturally occurring genomic HMGA1 binding sites, which should result in normalized gene expression and restored sensitivity to chemotherapy. As proof of principle, we engineered the replication defective adenovirus serotype 5 genome to contain hyper binding sites for HMGA1 composed of six copies of an individual HMGA1 binding site, referred to as HMGA-6. A 70%-80% reduction in cell viability and increased sensitivity to gemcitabine was observed in five different pancreatic and liver cancer cell lines 72 hr after infection with replication defective engineered adenovirus serotype 5 virus containing the HMGA-6 decoy hyper binding sites. The decoy hyper binding site strategy should be general for targeting overexpression of any double-stranded DNA-binding oncogenic transcription factor responsible for cancer cell proliferation.

  4. NADPH oxidase is not an essential mediator of oxidative stress or liver injury in murine MCD diet-induced steatohepatitis.

    Science.gov (United States)

    dela Peña, Aileen; Leclercq, Isabelle A; Williams, Jacqueline; Farrell, Geoffrey C

    2007-02-01

    Hepatic oxidative stress is a key feature of metabolic forms of steatohepatitis, but the sources of pro-oxidants are unclear. The NADPH oxidase complex is critical for ROS generation in inflammatory cells; loss of any one component (e.g., gp91phox) renders NADPH oxidase inactive. We tested whether activated inflammatory cells contribute to oxidant stress in steatohepatitis. gp91phox-/- and wildtype (wt) mice were fed a methionine and choline-deficient (MCD) diet. Serum ALT, hepatic triglycerides, histopathology, lipid peroxidation, activation of NF-kappaB, expression of NF-kappaB-regulated genes and macrophage chemokines were measured. After 10 days of MCD dietary feeding, gp91phox-/- and wt mice displayed equivalent hepatocellular injury. After 8 weeks, there were fewer activated macrophages in livers of gp91phox-/- mice than controls, despite similar mRNA levels for MCP and MIP chemokines, but fibrosis was similar. NF-kappaB activation and increased expression of ICAM-1, TNF-alpha and COX-2 mRNA were evident in both genotypes, but in gp91phox-/- mice, expression of these genes was confined to hepatocytes. A functional NADPH oxidase complex does not contribute importantly to oxidative stress in this model and therefore is not obligatory for induction or perpetuation of dietary steatohepatitis.

  5. Studies on the mechanism of pyrophosphate-mediated uptake of iron from transferrin by isolated rat-liver mitochondria

    International Nuclear Information System (INIS)

    Konopka, K.; Romslo, I.; Bergen Univ.

    1981-01-01

    1. Respiring rat liver mitochondria accumulate iron released from transferrin by pyrophosphate. The amount of iron accumulated is 1-1.5 nmol mg protein -1 h -1 , or approximately 60% of the amount of iron mobilized from transferrin. 2. The uptake declines if respiration is inhibited, substrate is depleted, or the experiments are run under anaerobic conditions. Substrate, depletion and respiratory inhibitors are less inhibitory under anaerobic conditions. 3. More than 80% of the amount of iron accumulated by aerobic, actively respiring mitochondria can be chelated by bathophenanthroline sulphonate, and with deuteroporphyrin included, up to 30% of the amount of iron accumulated is recovered as deuteroheme. Iron accumulated by respiration-inhibited mitochondria under aerobic conditions is not available for heme synthesis. 4. With time the uptake of iron increases eightfold relative to the uptake of pyrophosphate. 5. The results are compatible with a model in which ferric iron is mobilized from transferrin by pyrophosphate, ferric iron pyrophosphate is bound to the mitochondria, iron is reduced, dissociates from pyrophosphate and is taken up by the mitochondria. Ferrous irons thus formed is available for heme synthesis. (orig.) [de

  6. [Establishment of a D-galactosamine/lipopolysaccharide induced acute-on-chronic liver failure model in rats].

    Science.gov (United States)

    Liu, Xu-hua; Chen, Yu; Wang, Tai-ling; Lu, Jun; Zhang, Li-jie; Song, Chen-zhao; Zhang, Jing; Duan, Zhong-ping

    2007-10-01

    To establish a practical and reproducible animal model of human acute-on-chronic liver failure for further study of the pathophysiological mechanism of acute-on-chronic liver failure and for drug screening and evaluation in its treatment. Immunological hepatic fibrosis was induced by human serum albumin in Wistar rats. In rats with early-stage cirrhosis (fibrosis stage IV), D-galactosamine and lipopolysaccharide were administered. Mortality and survival time were recorded in 20 rats. Ten rats were sacrificed at 4, 8, and 12 hours. Liver function tests and plasma cytokine levels were measured after D-galactosamine/lipopolysaccharide administration and liver pathology was studied. Cell apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay. Most of the rats treated with human albumin developed cirrhosis and fibrosis, and 90% of them died from acute liver failure after administration of D-galactosamine/lipopolysaccharide, with a mean survival time of (16.1+/-3.7) hours. Liver histopathology showed massive or submassive necrosis of the regenerated nodules, while fibrosis septa were intact. Liver function tests were compatible with massive necrosis of hepatocytes. Plasma level of TNFalpha increased significantly, parallel with the degree of the hepatocytes apoptosis. Plasma IL-10 levels increased similarly as seen in patients with acute-on-chronic liver failure. We established an animal model of acute-on-chronic liver failure by treating rats with human serum albumin and later with D-galactosamine and lipopolysaccharide. TNFalpha-mediated liver cell apoptoses plays a very important role in the pathogenesis of acute liver failure.

  7. Liver fibrosis in mice induced by carbon tetrachloride and its reversion by luteolin

    International Nuclear Information System (INIS)

    Domitrovic, Robert; Jakovac, Hrvoje; Tomac, Jelena; Sain, Ivana

    2009-01-01

    Hepatic fibrosis is effusive wound healing process in which excessive connective tissue builds up in the liver. Because specific treatments to stop progressive fibrosis of the liver are not available, we have investigated the effects of luteolin on carbon tetrachloride (CCl 4 )-induced hepatic fibrosis. Male Balb/C mice were treated with CCl 4 (0.4 ml/kg) intraperitoneally (i.p.), twice a week for 6 weeks. Luteolin was administered i.p. once daily for next 2 weeks, in doses of 10, 25, and 50 mg/kg of body weight. The CCl 4 control group has been observed for spontaneous reversion of fibrosis. CCl 4 -intoxication increased serum aminotransferase and alkaline phosphatase levels and disturbed hepatic antioxidative status. Most of these parameters were spontaneously normalized in the CCl 4 control group, although the progression of liver fibrosis was observed histologically. Luteolin treatment has increased hepatic matrix metalloproteinase-9 levels and metallothionein (MT) I/II expression, eliminated fibrinous deposits and restored architecture of the liver in a dose-dependent manner. Concomitantly, the expression of glial fibrillary acidic protein and α-smooth muscle actin indicated deactivation of hepatic stellate cells. Our results suggest the therapeutic effects of luteolin on CCl 4 -induced liver fibrosis by promoting extracellular matrix degradation in the fibrotic liver tissue and the strong enhancement of hepatic regenerative capability, with MTs as a critical mediator of liver regeneration.

  8. c-Kit-mediated functional positioning of stem cells to their niches is essential for maintenance and regeneration of adult hematopoiesis.

    Directory of Open Access Journals (Sweden)

    Yuki Kimura

    Full Text Available The mechanism by which hematopoietic stem and progenitor cells (HSPCs through interaction with their niches maintain and reconstitute adult hematopoietic cells is unknown. To functionally and genetically track localization of HSPCs with their niches, we employed novel mutant loxPs, lox66 and lox71 and Cre-recombinase technology to conditionally delete c-Kit in adult mice, while simultaneously enabling GFP expression in the c-Kit-deficient cells. Conditional deletion of c-Kit resulted in hematopoietic failure and splenic atrophy both at steady state and after marrow ablation leading to the demise of the treated adult mice. Within the marrow, the c-Kit-expressing GFP(+ cells were positioned to Kit ligand (KL-expressing niche cells. This c-Kit-mediated cellular adhesion was essential for long-term maintenance and expansion of HSPCs. These results lay the foundation for delivering KL within specific niches to maintain and restore hematopoiesis.

  9. Sex bias in experimental immune-mediated, drug-induced liver injury in BALB/c mice: suggested roles for Tregs, estrogen, and IL-6.

    Directory of Open Access Journals (Sweden)

    Joonhee Cho

    Full Text Available Immune-mediated, drug-induced liver injury (DILI triggered by drug haptens is more prevalent in women than in men. However, mechanisms responsible for this sex bias are not clear. Immune regulation by CD4+CD25+FoxP3+ regulatory T-cells (Tregs and 17β-estradiol is crucial in the pathogenesis of sex bias in cancer and autoimmunity. Therefore, we investigated their role in a mouse model of immune-mediated DILI.To model DILI, we immunized BALB/c, BALB/cBy, IL-6-deficient, and castrated BALB/c mice with trifluoroacetyl chloride-haptenated liver proteins. We then measured degree of hepatitis, cytokines, antibodies, and Treg and splenocyte function.BALB/c females developed more severe hepatitis (p<0.01 and produced more pro-inflammatory hepatic cytokines and antibodies (p<0.05 than did males. Castrated males developed more severe hepatitis than did intact males (p<0.001 and females (p<0.05. Splenocytes cultured from female mice exhibited fewer Tregs (p<0.01 and higher IL-1β (p<0.01 and IL-6 (p<0.05 than did those from males. However, Treg function did not differ by sex, as evidenced by absence of sex bias in programmed death receptor-1 and responses to IL-6, anti-IL-10, anti-CD3, and anti-CD28. Diminished hepatitis in IL-6-deficient, anti-IL-6 receptor α-treated, ovariectomized, or male mice; undetectable IL-6 levels in splenocyte supernatants from ovariectomized and male mice; elevated splenic IL-6 and serum estrogen levels in castrated male mice, and IL-6 induction by 17β-estradiol in splenocytes from naïve female mice (p<0.05 suggested that 17β-estradiol may enhance sex bias through IL-6 induction, which subsequently discourages Treg survival. Treg transfer from naïve female mice to those with DILI reduced hepatitis severity and hepatic IL-6.17β-estradiol and IL-6 may act synergistically to promote sex bias in experimental DILI by reducing Tregs. Modulating Treg numbers may provide a therapeutic approach to DILI.

  10. Fructose Mediated Non-Alcoholic Fatty Liver Is Attenuated by HO-1-SIRT1 Module in Murine Hepatocytes and Mice Fed a High Fructose Diet.

    Directory of Open Access Journals (Sweden)

    Komal Sodhi

    Full Text Available Oxidative stress underlies the etiopathogenesis of nonalcoholic fatty liver disease (NAFLD, obesity and cardiovascular disease (CVD. Heme Oxygenase-1 (HO-1 is a potent endogenous antioxidant gene that plays a key role in decreasing oxidative stress. Sirtuin1 (SIRT1 belongs to the family of NAD-dependent de-acyetylases and is modulated by cellular redox.We hypothesize that fructose-induced obesity creates an inflammatory and oxidative environment conducive to the development of NAFLD and metabolic syndrome. The aim of this study is to determine whether HO-1 acts through SIRT1 to form a functional module within hepatocytes to attenuate steatohepatitis, hepatic fibrosis and cardiovascular dysfunction.We examined the effect of fructose, on hepatocyte lipid accumulation and fibrosis in murine hepatocytes and in mice fed a high fructose diet in the presence and absence of CoPP, an inducer of HO-1, and SnMP, an inhibitor of HO activity. Fructose increased oxidative stress markers and decreased HO-1 and SIRT1 levels in hepatocytes (p<0.05. Further fructose supplementation increased FAS, PPARα, pAMPK and triglycerides levels; CoPP negated this increase. Concurrent treatment with CoPP and SIRT1 siRNA in hepatocytes increased FAS, PPARα, pAMPK and triglycerides levels suggesting that HO-1 is upstream of SIRT1 and suppression of SIRT1 attenuates the beneficial effects of HO-1. A high fructose diet increased insulin resistance, blood pressure, markers of oxidative stress and lipogenesis along with fibrotic markers in mice (p<0.05. Increased levels of HO-1 increased SIRT1 levels and ameliorated fructose-mediated lipid accumulation and fibrosis in liver along with decreasing vascular dysfunction (p<0.05 vs. fructose. These beneficial effects of CoPP were reversed by SnMP.Taken together, our study demonstrates, for the first time, that HO-1 induction attenuates fructose-induced hepatic lipid deposition, prevents the development of hepatic fibrosis and abates

  11. Liver bioengineering: Current status and future perspectives

    Institute of Scientific and Technical Information of China (English)

    Christopher Booth; Tom Soker; Pedro Baptista; Christina L Ross; Shay Soker; Umar Farooq; Robert J Stratta

    2012-01-01

    The present review aims to illustrate the strategies that are being implemented to regenerate or bioengineer livers for clinical purposes.There are two general pathways to liver bioengineering and regeneration.The first consists of creating a supporting scaffold,either synthetically or by decellularization of human or animal organs,and seeding cells on the scaffold,where they will mature either in bioreactors or in vivo.This strategy seems to offer the quickest route to clinical translation,as demonstrated by the development of liver organoids from rodent livers which were repopulated with organ specific cells of animal and/or human origin.Liver bioengineering has potential for transplantation and for toxicity testing during preclinical drug development.The second possibility is to induce liver regeneration of dead or resected tissue by manipulating cell pathways.In fact,it is well known that the liver has peculiar regenerative potential which allows hepatocyte hyperplasia after amputation of liver volume.Infusion of autologous bone marrow cells,which aids in liver regeneration,into patients was shown to be safe and to improve their clinical condition,but the specific cells responsible for liver regeneration have not yet been determined and the underlying mechanisms remain largely unknown.A complete understanding of the cell pathways and dynamics and of the functioning of liver stem cell niche is necessary for the clinical translation of regenerative medicine strategies.As well,it will be crucial to elucidate the mechanisms through which cells interact with the extracellular matrix,and how this latter supports and drives cell fate.

  12. Regenerative response in the pig liver remnant varies with the degree of resection and rise in portal pressure

    DEFF Research Database (Denmark)

    Mortensen, Kim Erlend; Conley, Lene Nagsrrup; Hedegaard, Jakob

    2008-01-01

    After parenchymal loss, the liver regenerates restoring normal mass and metabolic function. Prevailing theories on triggering events leading to regeneration include humoral, metabolic, and flow-mediated mechanisms, the latter emphasizing the importance of shear stress mediated nitric oxide...... in the high portal pressure resection group to have functions related primarily to apoptosis, nitric oxide metabolism and oxidative stress, whereas differentially expressed genes in the low portal pressure resection group potentially regulate the cell cycle. Common to both groups was the upregulation of genes...... regulating inflammation, transport, cell proliferation, development, and protein metabolism. Also common to both groups was both up- and downregulation of genes regulating cell-cell signaling, signal transduction, cell adhesion, and translation. Genes regulating the metabolism of lipids, hormones, amines...

  13. Hepatic progenitors for liver disease: current position

    Directory of Open Access Journals (Sweden)

    Alice Conigliaro

    2010-02-01

    Full Text Available Alice Conigliaro1, David A Brenner2, Tatiana Kisseleva21University “La Sapienza”, Dipartimento di Biotecnologie Cellulari ed Ematologia Policlinico Umberto I, V Clinica Medica, Rome, Italy; 2Department of Medicine, University of California, San Diego, La Jolla, CA, USAAbstract: Liver regeneration restores the original functionality of hepatocytes and cholangiocytes in response to injury. It is regulated on several levels, with different cellular populations contributing to this process, eg, hepatocytes, liver precursor cells, intrahepatic stem cells. In response to injury, mature hepatocytes have the capability to proliferate and give rise to new hepatocytes and cholangiocytes. Meanwhile, liver precursor cells (oval cells have become the most recognized bipotential precursor cells in the damaged liver. They rapidly proliferate, change their cellular composition, and differentiate into hepatocytes and cholangiocytes to compensate for the cellular loss and maintain liver homeostasis. There is a growing body of evidence that oval cells originate from the intrahepatic stem cell(s, which in turn give(s rise to epithelial, including oval cells, and/or other hepatic cells of nonepithelial origin. Since there is a close relationship between the liver and hematopoiesis, bone marrow derived cells can also contribute to liver regeneration by the fusion of myeloid cells with damaged hepatocytes, or differentiation of mesenchymal stem cells into hepatocyte-like cells. The current review discusses the contribution of different cells to liver regeneration and their characteristics.Keywords: hepatic progenitor, liver disease, liver precursor cells, oval cells, hepatocytes, intrahepatic stem cells, cholangiocytes

  14. Adenovirus vector-mediated ex vivo gene transfer of brain-derived neurotrophic factor (BDNF) tohuman umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs) promotescrush-injured rat sciatic nerve regeneration.

    Science.gov (United States)

    Hei, Wei-Hong; Almansoori, Akram A; Sung, Mi-Ae; Ju, Kyung-Won; Seo, Nari; Lee, Sung-Ho; Kim, Bong-Ju; Kim, Soung-Min; Jahng, Jeong Won; He, Hong; Lee, Jong-Ho

    2017-03-16

    This study was designed toinvestigate the efficacy of adenovirus vector-mediated brain-derived neurotrophic factor (BDNF) ex vivo gene transfer to human umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs) in a rat sciatic nerve crush injury model. BDNF protein and mRNA expression after infection was checked through an enzyme-linked immunosorbent assay (ELISA) and quantitative real-time polymerase chain reaction (qRT-PCR). Male Sprague-Dawley rats (200-250g, 6 weeks old) were distributed into threegroups (n=20 each): the control group, UCB-MSC group, and BDNF-adenovirus infected UCB-MSC (BDNF-Ad+UCB-MSC) group. UCB-MSCs (1×10 6 cells/10μl/rat) or BDNF-Ad+UCB-MSCs (1×10 6 cells/10μl/rat)were transplantedinto the rats at the crush site immediately after sciatic nerve injury. Cell tracking was done with PKH26-labeled UCB-MSCs and BDNF-Ad+UCB-MSCs (1×10 6 cells/10μl/rat). The rats were monitored for 4 weeks post-surgery. Results showed that expression of BDNF at both the protein and mRNA levels was higher inthe BDNF-Ad+UCB-MSC group compared to theUCB-MSC group in vitro.Moreover, BDNF mRNA expression was higher in both UCB-MSC group and BDNF-Ad+ UCB-MSC group compared tothe control group, and BDNF mRNA expression in theBDNF-Ad+UCB-MSC group was higher than inboth other groups 5days after surgeryin vivo. Labeled neurons in the dorsal root ganglia (DRG), axon counts, axon density, and sciatic function index were significantly increased in the UCB-MSC and BDNF-Ad+ UCB-MSCgroupscompared to the controlgroup four weeksaftercell transplantation. Importantly,the BDNF-Ad+UCB-MSCgroup exhibited more peripheral nerve regeneration than the other two groups.Our results indicate thatboth UCB-MSCs and BDNF-Ad+UCB-MSCscan improve rat sciatic nerve regeneration, with BDNF-Ad+UCB-MSCsshowing a greater effectthan UCB-MSCs. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Rhein Elicits In Vitro Cytotoxicity in Primary Human Liver HL-7702 Cells by Inducing Apoptosis through Mitochondria-Mediated Pathway

    Directory of Open Access Journals (Sweden)

    Guy-Armel Bounda

    2015-01-01

    Full Text Available Objective. To study rhein-induced apoptosis signaling pathway and to investigate its molecular mechanisms in primary human hepatic cells. Results. Cell viability of HL-7702 cells treated with rhein showed significant decrease in dose-dependent manner. Following rhein treatment (25 μM, 50 μM, and 100 μM for 12 h, the detection of apoptotic cells was significantly analyzed by flow cytometry and nuclear morphological changes by Hoechst 33258, respectively. Fatty degeneration studies showed upregulation level of the relevant hepatic markers (P < 0.01. Caspase activities expressed significant upregulation of caspase-3, caspase-9, and caspase-8. Moreover, apoptotic cells by rhein were significantly inhibited by Z-LEHD-FMK and Z-DEVD-FMK, caspase-9 inhibitor, and caspase-3 inhibitor, respectively. Overproduction of reactive oxygen species, lipid peroxidation, and loss of mitochondrial membrane potential were detected by fluorometry. Additionally, NAC, a ROS scavenger, significantly attenuated rhein-induced oxidative damage in HL-7702 cells. Furthermore, real-time qPCR results showed significant upregulation of p53, PUMA, Apaf-1, and Casp-9 and Casp-3 mRNA, with no significant changes of Fas and Cytochrome-c. Immunoblotting revealed significant Cytochrome-c release from mitochondria into cytosol and no change in Fas expression. Conclusion. Taken together, these observations suggested that rhein could induce apoptosis in HL-7702 cells via mitochondria-mediated signal pathway with involvement of oxidative stress mechanism.

  16. Effect of Curcuma longa on CYP2D6- and CYP3A4-mediated metabolism of dextromethorphan in human liver microsomes and healthy human subjects.

    Science.gov (United States)

    Al-Jenoobi, Fahad Ibrahim; Al-Thukair, Areej A; Alam, Mohd Aftab; Abbas, Fawkeya A; Al-Mohizea, Abdullah M; Alkharfy, Khalid M; Al-Suwayeh, Saleh A

    2015-03-01

    Effect of Curcuma longa rhizome powder and its ethanolic extract on CYP2D6 and CYP3A4 metabolic activity was investigated in vitro using human liver microsomes and clinically in healthy human subjects. Dextromethorphan (DEX) was used as common probe for CYP2D6 and CYP3A4 enzymes. Metabolic activity of CYP2D6 and CYP3A4 was evaluated through in vitro study; where microsomes were incubated with NADPH in presence and absence of Curcuma extract. In clinical study phase-I, six healthy human subjects received a single dose (30 mg) of DEX syrup, and in phase-II DEX syrup was administered with Curcuma powder. The enzyme CYP2D6 and CYP3A4 mediated O- and N-demethylation of dextromethorphan into dextrorphan (DOR) and 3-methoxymorphinan (3-MM), respectively. Curcuma extract significantly inhibited the formation of DOR and 3-MM, in a dose-dependent and linear fashion. The 100 μg/ml dose of curcuma extract produced highest inhibition, which was about 70 % for DOR and 80 % for 3-MM. Curcuma significantly increases the urine metabolic ratio of DEX/DOR but the change in DEX/3-MM ratio was statistically insignificant. Present findings suggested that curcuma significantly inhibits the activity of CYP2D6 in in vitro as well as in vivo; which indicates that curcuma has potential to interact with CYP2D6 substrates.

  17. Desulfurization sorbent regeneration

    Science.gov (United States)

    Jalan, V.M.; Frost, D.G.

    1982-07-07

    A spent solid sorbent resulting from the removal of hydrogen sulfide from a fuel gas flow is regenerated with a steam-air mixture. The mixture of steam and air may also include additional nitrogen or carbon dioxide. The gas mixture contacts the spent sorbent containing metal sulfide at a temperature above 500/sup 0/C to regenerate the sulfide to metal oxide or carbonate. Various metal species including the period four transition metals and the lanthanides are suitable sorbents that may be regenerated by this method. In addition, the introduction of carbon dioxide gas permits carbonates such as those of strontium, barium and calcium to be regenerated. The steam permits regeneration of spent sorbent without formation of metal sulfate. Moreover, the regeneration will proceed with low oxygen concentrations and will occur without the increase in temperature to minimize the risk of sintering and densification of the sorbent. This method may be used for high-temperature fuel cells.

  18. No evidence of in vitro and in vivo porcine endogenous retrovirus infection after plasmapheresis through the AMC-bioartificial liver

    NARCIS (Netherlands)

    Di Nicuolo, Giuseppe; van de Kerkhove, Maarten-Paul; Hoekstra, Ruurdtje; Beld, Marcel G. H. M.; Amoroso, Pietro; Battisti, Sonia; Starace, Maria; di Florio, Ernesto; Scuderi, Vincenzo; Scala, Simona; Bracco, Adele; Mancini, Antonio; Chamuleau, Robert A. F. M.; Calise, Fulvio

    2005-01-01

    Background: Currently a number of bioartificial livers (BAL) based on porcine liver cells have been developed as a treatment to bridge acute liver failure patients to orthotopic liver transplantation or liver regeneration. These xenotransplantation related treatments hold the risk of infection of

  19. On marginal regeneration

    NARCIS (Netherlands)

    Stein, H.N.

    1991-01-01

    On applying the marginal regeneration concept to the drainage of free liquid films, problems are encountered: the films do not show a "neck" of minimum thickness at the film/border transition; and the causes of the direction dependence of the marginal regeneration are unclear. Both problems can be

  20. Salvianolic acid A preconditioning confers protection against concanavalin A-induced liver injury through SIRT1-mediated repression of p66shc in mice

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Xiaomei; Hu, Yan; Zhai, Xiaohan; Lin, Musen [Department of Pharmacology, Dalian Medical University, Dalian 116044 (China); Chen, Zhao; Tian, Xiaofeng; Zhang, Feng [Department of General Surgery, Second Affiliated Hospital of Dalian Medical University, Dalian 116023 (China); Gao, Dongyan; Ma, Xiaochi [Department of Pharmacology, Dalian Medical University, Dalian 116044 (China); Lv, Li, E-mail: lv_li@126.com [Department of Pharmacology, Dalian Medical University, Dalian 116044 (China); Yao, Jihong, E-mail: Yaojihong65@hotmail.com [Department of Pharmacology, Dalian Medical University, Dalian 116044 (China)

    2013-11-15

    Salvianolic acid A (SalA) is a phenolic carboxylic acid derivative extracted from Salvia miltiorrhiza. It has many biological and pharmaceutical activities. The purpose of this study was to investigate the effect of SalA on concanavalin A (ConA)-induced acute hepatic injury in Kunming mice and to explore the role of SIRT1 in such an effect. The results showed that in vivo pretreatment with SalA significantly reduced ConA-induced elevation in serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities and decreased levels of the hepatotoxic cytokines such as interferon-gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-α). Moreover, the SalA pretreatment ameliorated the increases in NF-κB and in cleaved caspase-3 caused by ConA exposure. Whereas, the pretreatment completely reversed expression of the B-cell lymphoma-extra large (Bcl-xL). More importantly, the SalA pretreatment significantly increased the expression of SIRT1, a NAD{sup +}-dependent deacetylase, which was known to attenuate acute hypoxia damage and metabolic liver diseases. In our study, the increase in SIRT1 was closely associated with down-regulation of the p66 isoform (p66shc) of growth factor adapter Shc at both protein and mRNA levels. In HepG2 cell culture, SalA pretreatment increased SIRT1 expression in a time and dose-dependent manner and such an increase was abrogated by siRNA knockdown of SIRT1. Additionally, inhibition of SIRT1 significantly reversed the decreased expression of p66shc, and attenuated SalA-induced p66shc down-regulation. Collectively, the present study indicated that SalA may be a potent activator of SIRT and that SalA can alleviate ConA-induced hepatitis through SIRT1-mediated repression of the p66shc pathway. - Highlights: • We report for the first time that SalA protects against ConA-induced hepatitis. • We find that SalA is a potential activator of SIRT1. • SalA's protection against hepatitis involves SIRT1-mediated repression of p

  1. Liver Hemangioma

    Science.gov (United States)

    Liver hemangioma Overview A liver hemangioma (he-man-jee-O-muh) is a noncancerous (benign) mass in the liver. A liver hemangioma is made up of a tangle of blood vessels. Other terms for a liver hemangioma are hepatic hemangioma and cavernous hemangioma. Most ...

  2. LPS-Toll-Like Receptor-Mediated Signaling on Expression of Protein S and C4b-Binding Protein in the Liver

    Directory of Open Access Journals (Sweden)

    Tatsuya Hayashi

    2010-01-01

    Full Text Available Protein S (PS, mainly synthesized in hepatocytes and endothelial cells, plays a critical role as a cofactor of anticoagulant activated protein C (APC. PS activity is regulated by C4b-binding protein (C4BP, structurally composed of seven α-chains (C4BPα and a β-chain (C4BPβ. In this paper, based primarily on our previous studies, we review the lipopolysaccharide (LPS-induced signaling which affects expression of PS and C4BP in the liver. Our in vivo studies in rats showed that after LPS injection, plasma PS levels are significantly decreased, whereas plasma C4BP levels first are transiently decreased after 2 to 12 hours and then significantly increased after 24 hours. LPS decreases PS antigen and mRNA levels in both hepatocytes and sinusoidal endothelial cells (SECs, and decreases C4BP antigen and both C4BPα and C4BPβ mRNA levels in hepatocytes. Antirat CD14 and antirat Toll-like receptor (TLR-4 antibodies inhibited LPS-induced NFκB activation in both hepatocytes and SECs. Furthermore, inhibitors of NFκB and MEK recovered the LPS-induced decreased expression of PS in both cell types and the LPS-induced decreased expression of C4BP in hepatocytes. These data suggest that the LPS-induced decrease in PS expression in hepatocytes and SECs and LPS-induced decrease in C4BP expression in hepatocytes are mediated by MEK/ERK signaling and NFκB activation and that membrane-bound CD14 and TLR-4 are involved in this mechanism.

  3. Hepatic resection and regeneration. Past and present

    International Nuclear Information System (INIS)

    Hatsuse, Kazuo

    2007-01-01

    Hepatic surgery has been performed on condition that the liver regenerates after hepatic resection, and the development of liver anatomy due to Glisson, Rex, and Couinaud has thrown light on hepatic surgery Understanding of feeding and drainage vessels became feasible for systemic hepatic resection; however, it seems to have been the most important problem to control the bleeding during hepatic resection. New types of devices such as cavitron ultrasonic surgical aspirator (CUSA) and Microwave coagulation were exploited to control blood loss during hepatic surgery. Pringle maneuver for exclusion feeding vessels of the liver and the decrease of central venous pressure during anesthesia enabled further decrease of blood loss. Nowadays, 3D-CT imaging may depict feeding and drainage vessels in relation to liver mass, and surgeons can simulate hepatic surgery in virtual reality before surgery, allowing hepatectomy to be performed without blood transfusion. Thus, hepatic resection has been a safe procedure, but there's been a significant research on how much of the liver can be resected without hepatic failure. A prediction scoring system based on ICGR15, resection rates, and age is mostly reliable in some criteria. Even if hepatectomy is performed with a good prediction score, the massive bleeding and associated infection may induce postoperative hepatic failure, while the criteria of postoperative hepatic failure have not yet established. Hepatic failure is supposed to be induced by the apoptosis of mature hepatocytes and necrosis originated from microcirculation disturbance of the liver. Prostaglandin E1 for the improvement of microcirculation, steroid for the inhibition of cytokines inducing apoptosis, and blood purification to exclude cytokines have been tried separately or concomitantly. New therapeutic approaches, especially hepatic regeneration from the stem cell, are expected. (author)

  4. Proliferative human cell sources applied as biocomponent in bioartificial livers: a review

    NARCIS (Netherlands)

    Nibourg, Geert A. A.; Chamuleau, Robert A. F. M.; van Gulik, Thomas M.; Hoekstra, Ruurdtje

    2012-01-01

    Introduction: Bioartificial livers (BALs) are urgently needed to bridge severe liver failure patients to liver transplantation or liver regeneration. When based on primary hepatocytes, their efficacy has been shown in animal experiments and their safety was confirmed in clinical trials. However, a

  5. Liver biopsy

    Science.gov (United States)

    Biopsy - liver; Percutaneous biopsy ... the biopsy needle to be inserted into the liver. This is often done by using ultrasound. The ... the chance of damage to the lung or liver. The needle is removed quickly. Pressure will be ...

  6. Extraocular muscle regeneration in zebrafish requires late signals from Insulin-like growth factors.

    Science.gov (United States)

    Saera-Vila, Alfonso; Louie, Ke'ale W; Sha, Cuilee; Kelly, Ryan M; Kish, Phillip E; Kahana, Alon

    2018-01-01

    Insulin-like growth factors (Igfs) are key regulators of key biological processes such as embryonic development, growth, and tissue repair and regeneration. The role of Igf in myogenesis is well documented and, in zebrafish, promotes fin and heart regeneration. However, the mechanism of action of Igf in muscle repair and regeneration is not well understood. Using adult zebrafish extraocular muscle (EOM) regeneration as an experimental model, we show that Igf1 receptor blockage using either chemical inhibitors (BMS754807 and NVP-AEW541) or translation-blocking morpholino oligonucleotides (MOs) reduced EOM regeneration. Zebrafish EOMs regeneration depends on myocyte dedifferentiation, which is driven by early epigenetic reprogramming and requires autophagy activation and cell cycle reentry. Inhibition of Igf signaling had no effect on either autophagy activation or cell proliferation, indicating that Igf signaling was not involved in the early reprogramming steps of regeneration. Instead, blocking Igf signaling produced hypercellularity of regenerating EOMs and diminished myosin expression, resulting in lack of mature differentiated muscle fibers even many days after injury, indicating that Igf was involved in late re-differentiation steps. Although it is considered the main mediator of myogenic Igf actions, Akt activation decreased in regenerating EOMs, suggesting that alternative signaling pathways mediate Igf activity in muscle regeneration. In conclusion, Igf signaling is critical for re-differentiation of reprogrammed myoblasts during late steps of zebrafish EOM regeneration, suggesting a regulatory mechanism for determining regenerated muscle size and timing of differentiation, and a potential target for regenerative therapy.

  7. Regeneration and Agrobacterium -mediated transformation studies ...

    African Journals Online (AJOL)

    Leaf explants of carnation (Dianthus caryophyllus L. cv. Turbo) were used for the transformation of gene performed by the EHA 105 strain of Agrobacterium tumefaciens harboring the binary vector, pGA482GG. This vector carries the marker genes, neomycin phosphotansferase II (npt II) that determine resistance to ...

  8. Agrobacterium mediated genetic transformation and regeneration in ...

    African Journals Online (AJOL)

    Aghomotsegin

    2015-03-11

    Mar 11, 2015 ... 100 µM acetosyringone in co-cultivation medium and co-cultivation for 3 days were the .... for 11 days, micro calli could be observed which were finally ..... plants algae and fungi, in: S.B. Gelvin, R.A. Schilperoort, D.P.S..

  9. Autoimmune liver disease and therapy in childhood

    Directory of Open Access Journals (Sweden)

    Matjaž Homan

    2013-10-01

    Full Text Available Autoimmune hepatitis is a chronic immune-mediated disease of the liver. In childhood, autoimmune liver disorders include autoimmune hepatitis type I and II, autoimmune sclerosing cholangitis, Coombs-positive giant cell hepatitis, and de novo autoimmune hepatitis after liver transplantation. Autoimmune liver disease has a more aggressive course in children, especially autoimmune hepatitis type II. Standard therapy is a combination of corticosteroids and azathioprine. Around 80 % of children with autoimmune liver disease show a rapid response to combination therapy. The non-responders are treated with more potent drugs, otherwise autoimmune disease progresses to cirrhosis of the liver and the child needs liver transplantation as rescue therapy.

  10. Helping the Retina Regenerate

    Science.gov (United States)

    ... the retina News Brief 03/30/17 A new report gives recommendations for regenerating retinal ganglion cells (RGCs), crucial neurons in the back of the eye that carry visual information to the brain. Authored ...

  11. Isolation of Mallory bodies and an attempt to demonstrate cell mediated immunity to Mallory body isolate in patients with alcoholic liver disease

    DEFF Research Database (Denmark)

    Gluud, C; Hardt, F; Aldershvile, J

    1981-01-01

    Mallory bodies were isolated from necropsy livers from patients with alcoholic hepatitis with and without cirrhosis with a Ficoll viscosity barrier. The purity of Mallory bodies in the isolate varied between 70 and 90%, estimated by counting Mallory bodies and non-Mallory body structures in haema...... was found between controls and patients with alcoholic hepatitis, alcoholic steatosis, alcoholic cirrhosis and miscellaneous liver diseases.......Mallory bodies were isolated from necropsy livers from patients with alcoholic hepatitis with and without cirrhosis with a Ficoll viscosity barrier. The purity of Mallory bodies in the isolate varied between 70 and 90%, estimated by counting Mallory bodies and non-Mallory body structures...

  12. Peroxisome proliferator-activated receptor alpha acts as a mediator of endoplasmic reticulum stress-induced hepatocyte apoptosis in acute liver failure

    Directory of Open Access Journals (Sweden)

    Li Zhang

    2016-07-01

    Full Text Available Peroxisome proliferator-activated receptor α (PPARα is a key regulator to ameliorate liver injury in cases of acute liver failure (ALF. However, its regulatory mechanisms remain largely undetermined. Endoplasmic reticulum stress (ER stress plays an important role in a number of liver diseases. This study aimed to investigate whether PPARα activation inhibits ER stress-induced hepatocyte apoptosis, thereby protecting against ALF. In a murine model of D-galactosamine (D-GalN- and lipopolysaccharide (LPS-induced ALF, Wy-14643 was administered to activate PPARα, and 4-phenylbutyric acid (4-PBA was administered to attenuate ER stress. PPARα activation ameliorated liver injury, because pre-administration of its specific inducer, Wy-14643, reduced the serum aminotransferase levels and preserved liver architecture compared with that of controls. The protective effect of PPARα activation resulted from the suppression of ER stress-induced hepatocyte apoptosis. Indeed, (1 PPARα activation decreased the expression of glucose-regulated protein 78 (Grp78, Grp94 and C/EBP-homologous protein (CHOP in vivo; (2 the liver protection by 4-PBA resulted from the induction of PPARα expression, as 4-PBA pre-treatment promoted upregulation of PPARα, and inhibition of PPARα by small interfering RNA (siRNA treatment reversed liver protection and increased hepatocyte apoptosis; (3 in vitro PPARα activation by Wy-14643 decreased hepatocyte apoptosis induced by severe ER stress, and PPARα inhibition by siRNA treatment decreased the hepatocyte survival induced by mild ER stress. Here, we demonstrate that PPARα activation contributes to liver protection and decreases hepatocyte apoptosis in ALF, particularly through regulating ER stress. Therefore, targeting PPARα could be a potential therapeutic strategy to ameliorate ALF.

  13. An oral Salmonella-based vaccine inhibits liver metastases by promoting tumor-specific T cell-mediated immunity in celiac & portal lymph nodes. A preclinical study.

    Directory of Open Access Journals (Sweden)

    Alejandrina eVendrell

    2016-03-01

    Full Text Available Primary tumor excision is one of the therapies of cancer most widely used. However, the risk of metastases development still exists following tumor resection. The liver is a common site of metastatic disease for numerous cancers. Breast cancer is one of the most frequent source of metastases to the liver. The aim of this work was to evaluate the efficacy of the orally-administered Salmonella Typhi vaccine strain CVD 915 on the development of liver metastases in a mouse model of breast cancer. To this end, one group of BALB/c mice was immunized with CVD 915 via o.g. while another received PBS as a control. After 24 h, mice were injected with LM3 mammary adenocarcinoma cells into the spleen and subjected to splenectomy. This oral Salmonella-based vaccine produced an antitumor effect, leading to a decrease in the number and volume of liver metastases. Immunization with Salmonella induced an early cellular immune response in mice. This innate stimulation rendered a large production of IFN-γ by intrahepatic immune cells (IHIC detected within 24 h. An antitumor adaptive immunity was found in the liver and celiac & portal lymph nodes (LDLN 21 days after oral bacterial inoculation. The antitumor immune response inside the liver was associated with increased CD4+ and DC cell populations as well as with an inflammatory infiltrate located around liver metastatic nodules. Enlarged levels of inflammatory cytokines (IFN-γ and TNF were also detected in IHIC. Furthermore, a tumor-specific production of IFN-γ and TNF as well as tumor-specific IFN-γ-producing CD8 T cells (CD8+IFN-γ+ were found in the celiac & portal lymph nodes of Salmonella-treated mice. This study provides first evidence for the involvement of LDLN in the development of an efficient cellular immune response against hepatic tumors, which resulted in the elimination of liver metastases after oral Salmonella-based vaccination.

  14. Phosphodiesterase inhibition mediates matrix metalloproteinase activity and the level of collagen degradation fragments in a liver fibrosis ex vivo rat model

    Directory of Open Access Journals (Sweden)

    Veidal Sanne Skovgård

    2012-12-01

    Full Text Available Abstract Background Accumulation of extracellular matrix (ECM and increased matrix metalloproteinase (MMP activity are hallmarks of liver fibrosis. The aim of the present study was to develop a model of liver fibrosis combining ex vivo tissue culture of livers from CCl4 treated animals with an ELISA detecting a fragment of type III collagen generated in vitro by MMP-9 (C3M, known to be associated with liver fibrosis and to investigate cAMP modulation of MMP activity and liver tissue turnover in this model. Findings In vivo: Rats were treated for 8 weeks with CCl4/Intralipid. Liver slices were cultured for 48 hours. Levels of C3M were determined in the supernatants of slices cultured without treatment, treated with GM6001 (positive control or treated with IBMX (phosphodiesterase inhibitor. Enzymatic activity of MMP-2 and MMP-9 were studied by gelatin zymography. Ex vivo: The levels of serum C3M increased 77% in the CCl4-treated rats at week 8 (p 4-treated animals had highly increased MMP-9, but not MMP-2 activity, compared to slices derived from control animals. Conclusions We have combined an ex vivo model of liver fibrosis with measurement of a biochemical marker of collagen degradation in the condition medium. This technology may be used to evaluate the molecular process leading to structural fibrotic changes, as collagen species are the predominant structural part of fibrosis. These data suggest that modulation of cAMP may play a role in regulation of collagen degradation associated with liver fibrosis.

  15. High-Fat Diet Augments VPAC1 Receptor-Mediated PACAP Action on the Liver, Inducing LAR Expression and Insulin Resistance

    Directory of Open Access Journals (Sweden)

    Masanori Nakata

    2016-01-01

    Full Text Available Pituitary adenylate cyclase-activating polypeptide (PACAP acts on multiple processes of glucose and energy metabolism. PACAP potentiates insulin action in adipocytes and insulin release from pancreatic β-cells, thereby enhancing glucose tolerance. Contrary to these effects at organ levels, PACAP null mice exhibit hypersensitivity to insulin. However, this apparent discrepancy remains to be solved. We aimed to clarify the mechanism underlying the antidiabetic phenotype of PACAP null mice. Feeding with high-fat diet (HFD impaired insulin sensitivity and glucose tolerance in wild type mice, whereas these changes were prevented in PACAP null mice. HFD also impaired insulin-induced Akt phosphorylation in the liver in wild type mice, but not in PACAP null mice. Using GeneFishing method, HFD increased the leukocyte common antigen-related (LAR protein tyrosine phosphatase in the liver in wild type mice. Silencing of LAR restored the insulin signaling in the liver of HFD mice. Moreover, the increased LAR expression by HFD was prevented in PACAP null mice. HFD increased the expression of VPAC1 receptor (VPAC1-R, one of three PACAP receptors, in the liver of wild type mice. These data indicate that PACAP-VPAC1-R signaling induces LAR expression and insulin resistance in the liver of HFD mice. Antagonism of VPAC1-R may prevent progression of HFD-induced insulin resistance in the liver, providing a novel antidiabetic strategy.

  16. Modeling toxicodynamic effects of trichloroethylene on liver in mouse model of autoimmune hepatitis.

    Science.gov (United States)

    Gilbert, Kathleen M; Reisfeld, Brad; Zurlinden, Todd J; Kreps, Meagan N; Erickson, Stephen W; Blossom, Sarah J

    2014-09-15

    Chronic exposure to industrial solvent and water pollutant trichloroethylene (TCE) in female MRL+/+mice generates disease similar to human autoimmune hepatitis. The current study was initiated to investigate why TCE-induced autoimmunity targeted the liver. Compared to other tissues the liver has an unusually robust capacity for repair and regeneration. This investigation examined both time-dependent and dose-dependent effects of TCE on hepatoprotective and pro-inflammatory events in liver and macrophages from female MRL+/+mice. After a 12-week exposure to TCE in drinking water a dose-dependent decrease in macrophage production of IL-6 at both the transcriptional and protein level was observed. A longitudinal study similarly showed that TCE inhibited macrophage IL-6 production. In terms of the liver, TCE had little effect on expression of pro-inflammatory genes (Tnfa, Saa2 or Cscl1) until the end of the 40-week exposure. Instead, TCE suppressed hepatic expression of genes involved in IL-6 signaling (Il6r, gp130, and Egr1). Linear regression analysis confirmed liver histopathology in the TCE-treated mice correlated with decreased expression of Il6r. A toxicodynamic model was developed to estimate the effects of TCE on IL-6 signaling and liver pathology under different levels of exposure and rates of repair. This study underlined the importance of longitudinal studies in mechanistic evaluations of immuntoxicants. It showed that later-occurring liver pathology caused by TCE was associated with early suppression of hepatoprotection rather than an increase in conventional pro-inflammatory events. This information was used to create a novel toxicodynamic model of IL-6-mediated TCE-induced liver inflammation. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Modeling toxicodynamic effects of trichloroethylene on liver in mouse model of autoimmune hepatitis

    Energy Technology Data Exchange (ETDEWEB)

    Gilbert, Kathleen M., E-mail: gilbertkathleenm@uams.edu [University of Arkansas for Medical Sciences, Arkansas Children' s Hospital Research Institute, Little Rock, AR 72202 (United States); Reisfeld, Brad, E-mail: brad.reisfeld@colostate.edu [Colorado State University, Fort Collins, CO (United States); Zurlinden, Todd J., E-mail: tjzurlin@rams.colostate.edu [Colorado State University, Fort Collins, CO (United States); Kreps, Meagan N., E-mail: MNKreps@uams.edu [University of Arkansas for Medical Sciences, Arkansas Children' s Hospital Research Institute, Little Rock, AR 72202 (United States); Erickson, Stephen W., E-mail: serickson@uams.edu [University of Arkansas for Medical Sciences, Arkansas Children' s Hospital Research Institute, Little Rock, AR 72202 (United States); Blossom, Sarah J., E-mail: blossomsarah@uams.edu [University of Arkansas for Medical Sciences, Arkansas Children' s Hospital Research Institute, Little Rock, AR 72202 (United States)

    2014-09-15

    Chronic exposure to industrial solvent and water pollutant trichloroethylene (TCE) in female MRL +/+ mice generates disease similar to human autoimmune hepatitis. The current study was initiated to investigate why TCE-induced autoimmunity targeted the liver. Compared to other tissues the liver has an unusually robust capacity for repair and regeneration. This investigation examined both time-dependent and dose-dependent effects of TCE on hepatoprotective and pro-inflammatory events in liver and macrophages from female MRL +/+ mice. After a 12-week exposure to TCE in drinking water a dose-dependent decrease in macrophage production of IL-6 at both the transcriptional and protein level was observed. A longitudinal study similarly showed that TCE inhibited macrophage IL-6 production. In terms of the liver, TCE had little effect on expression of pro-inflammatory genes (Tnfa, Saa2 or Cscl1) until the end of the 40-week exposure. Instead, TCE suppressed hepatic expression of genes involved in IL-6 signaling (Il6r, gp130, and Egr1). Linear regression analysis confirmed liver histopathology in the TCE-treated mice correlated with decreased expression of Il6r. A toxicodynamic model was developed to estimate the effects of TCE on IL-6 signaling and liver pathology under different levels of exposure and rates of repair. This study underlined the importance of longitudinal studies in mechanistic evaluations of immuntoxicants. It showed that later-occurring liver pathology caused by TCE was associated with early suppression of hepatoprotection rather than an increase in conventional pro-inflammatory events. This information was used to create a novel toxicodynamic model of IL-6-mediated TCE-induced liver inflammation. - Highlights: • We developed a toxicodynamic model to study effects of trichloroethylene on liver. • We examined protective as well as pro-inflammatory events in the liver. • Trichloroethylene inhibits IL-6 production by macrophages. • Trichloroethylene

  18. Modeling toxicodynamic effects of trichloroethylene on liver in mouse model of autoimmune hepatitis

    International Nuclear Information System (INIS)

    Gilbert, Kathleen M.; Reisfeld, Brad; Zurlinden, Todd J.; Kreps, Meagan N.; Erickson, Stephen W.; Blossom, Sarah J.

    2014-01-01

    Chronic exposure to industrial solvent and water pollutant trichloroethylene (TCE) in female MRL +/+ mice generates disease similar to human autoimmune hepatitis. The current study was initiated to investigate why TCE-induced autoimmunity targeted the liver. Compared to other tissues the liver has an unusually robust capacity for repair and regeneration. This investigation examined both time-dependent and dose-dependent effects of TCE on hepatoprotective and pro-inflammatory events in liver and macrophages from female MRL +/+ mice. After a 12-week exposure to TCE in drinking water a dose-dependent decrease in macrophage production of IL-6 at both the transcriptional and protein level was observed. A longitudinal study similarly showed that TCE inhibited macrophage IL-6 production. In terms of the liver, TCE had little effect on expression of pro-inflammatory genes (Tnfa, Saa2 or Cscl1) until the end of the 40-week exposure. Instead, TCE suppressed hepatic expression of genes involved in IL-6 signaling (Il6r, gp130, and Egr1). Linear regression analysis confirmed liver histopathology in the TCE-treated mice correlated with decreased expression of Il6r. A toxicodynamic model was developed to estimate the effects of TCE on IL-6 signaling and liver pathology under different levels of exposure and rates of repair. This study underlined the importance of longitudinal studies in mechanistic evaluations of immuntoxicants. It showed that later-occurring liver pathology caused by TCE was associated with early suppression of hepatoprotection rather than an increase in conventional pro-inflammatory events. This information was used to create a novel toxicodynamic model of IL-6-mediated TCE-induced liver inflammation. - Highlights: • We developed a toxicodynamic model to study effects of trichloroethylene on liver. • We examined protective as well as pro-inflammatory events in the liver. • Trichloroethylene inhibits IL-6 production by macrophages. • Trichloroethylene

  19. Protective effect of fucoidan from Fucus vesiculosus on liver fibrosis via the TGF-β1/Smad pathway-mediated inhibition of extracellular matrix and autophagy

    Directory of Open Access Journals (Sweden)

    Li J

    2016-02-01

    Full Text Available Jingjing Li,1 Kan Chen,1 Sainan Li,1 Jiao Feng,1 Tong Liu,1 Fan Wang,1 Rong Zhang,1,2 Shizan Xu,1,2 Yuqing Zhou,1,3 Shunfeng Zhou,1,3 Yujing Xia,1 Jie Lu,1 Yingqun Zhou,1 Chuanyong Guo1 1Department of Gastroenterology, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai, 2The First Clinical Medical College of Nanjing Medical University, Nanjing, 3Department of Gastroenterology, The First Affiliated Hospital of Soochow University, Suzhou, People’s Republic of China Abstract: Liver fibrosis is a dynamic reversible pathological process in the development of chronic liver disease to cirrhosis. However, the current treatments are not administered for a long term due to their various side effects. Autophagy is initiated to decompose damaged or excess organelles, which had been found to alter the progression of liver fibrosis. In this article, we hypothesized that fucoidan from Fucus vesiculosus may attenuate liver fibrosis in mice by inhibition of the extracellular matrix and autophagy in carbon tetrachloride- and bile duct ligation-induced animal models of liver fibrosis. The results were determined using enzyme-linked immunosorbent assay, quantitative real-time polymerase chain reaction, Western blotting, and immunohistochemical staining. Fucoidan from F. vesiculosus could inhibit the activation of hepatic stellate cells and the formation of extracellular matrix and autophagosomes, and its effect may be associated with the downregulation of transforming growth factor beta 1/Smads pathways. Fucoidan, as an autophagy and transforming growth factor beta 1 inhibitor, could be a promising potential therapeutic agent for liver fibrosis. Keywords: liver cirrhosis, hepatic stellate cells, bile duct ligation

  20. Perfluorodecalin and bone regeneration

    Directory of Open Access Journals (Sweden)

    F Tamimi

    2013-01-01

    Full Text Available Perfluorodecalin (PFD is a chemically and biologically inert biomaterial and, as many perfluorocarbons, is also hydrophobic, radiopaque and has a high solute capacity for gases such as oxygen. In this article we have demonstrated, both in vitro and in vivo, that PFD may significantly enhance bone regeneration. Firstly, the potential benefit of PFD was demonstrated by prolonging the survival of bone marrow cells cultured in anaerobic conditions. These findings translated in vivo, where PFD incorporated into bone-marrow-loaded 3D-printed scaffolds substantially improved their capacity to regenerate bone. Secondly, in addition to biological applications, we have also shown that PFD improves the radiopacity of bone regeneration biomaterials, a key feature required for the visualisation of biomaterials during and after surgical implantation. Finally, we have shown how the extreme hydrophobicity of PFD enables the fabrication of highly cohesive self-setting injectable biomaterials for bone regeneration. In conclusion, perfluorocarbons would appear to be highly beneficial additives to a number of regenerative biomaterials, especially those for bone regeneration.

  1. Ex vivo adenoviral vector-mediated neurotrophin gene transfer to olfactory ensheathing glia : effects on rubrospinal tract regeneration, lesion size, and functional recovery after implantation in the injured rat spinal cord

    NARCIS (Netherlands)

    Ruitenberg, Marc J; Plant, Giles W; Hamers, Frank P T; Wortel, Joke; Blits, Bas; Dijkhuizen, Paul A; Gispen, Willem Hendrik; Boer, Gerard J; Verhaagen, J.

    2003-01-01

    The present study uniquely combines olfactory ensheathing glia (OEG) implantation with ex vivo adenoviral (AdV) vector-based neurotrophin gene therapy in an attempt to enhance regeneration after cervical spinal cord injury. Primary OEG were transduced with AdV vectors encoding rat brain-derived

  2. Fucoidan from Fucus vesiculosus Protects against Alcohol-Induced Liver Damage by Modulating Inflammatory Mediators in Mice and HepG2 Cells

    Directory of Open Access Journals (Sweden)

    Jung Dae Lim

    2015-02-01

    Full Text Available Fucoidan is an l-fucose-enriched sulfated polysaccharide isolated from brown algae and marine invertebrates. In this study, we investigated the protective effect of fucoidan from Fucus vesiculosus on alcohol-induced murine liver damage. Liver injury was induced by oral administration of 25% alcohol with or without fucoidan (30 mg/kg or 60 mg/kg for seven days. Alcohol administration increased serum aspartate aminotransferase and alanine aminotransferase levels, but these increases were suppressed by the treatment of fucoidan. Transforming growth factor beta 1 (TGF-β1, a liver fibrosis-inducing factor, was highly expressed in the alcohol-fed group and human hepatoma HepG2 cell; however, the increase in TGF-β1 expression was reduced following fucoidan administration. Treatment with fucoidan was also found to significantly reduce the production of inflammation-promoting cyclooygenase-2 and nitric oxide, while markedly increasing the expression of the hepatoprotective enzyme, hemeoxygenase-1, on murine liver and HepG2 cells. Taken together, the antifibrotic and anti-inflammatory effects of fucoidan on alcohol-induced liver damage may provide valuable insights into developing new therapeutics or interventions.

  3. MMP Mediated Degradation of Type VI Collagen Is Highly Associated with Liver Fibrosis - Identification and Validation of a Novel Biochemical Marker Assay

    DEFF Research Database (Denmark)

    Veidal, Sanne Skovgard; Karsdal, Morten Asser; Vassiliadis, Efstathios

    2011-01-01

    Background and Aims: During fibrogenesis, in which excessive remodeling of the extracellular matrix occurs, both the quantity of type VI collagen and levels of matrix metalloproteinases, including MMP-2 and MMP-9, increase significantly. Proteolytic degradation of type VI collagen into small...... fragments, so-called neo-epitopes, may be specific biochemical marker of liver fibrosis. The aim of this study was to develop an ELISA detecting a fragment of type VI collagen generated by MMP-2 and MMP-9, and evaluate this assay in two preclinical models of liver fibrosis. Methods: Mass spectrometric...... analysis of cleaved type VI collagen revealed a large number of protease-generated neo-epitopes. A fragment unique to type VI collagen generated by MMP-2 and MMP-9 was selected for ELISA development. The CO6-MMP assay was evaluated in two rat models of liver fibrosis: bile duct ligation (BDL) and carbon...

  4. Caspase-3 mediates the pathogenic effect of Yersinia pestis YopM in liver of C57BL/6 mice and contributes to YopM's function in spleen.

    Directory of Open Access Journals (Sweden)

    Zhan Ye

    Full Text Available The virulence protein YopM of the plague bacterium Yersinia pestis has different dominant effects in liver and spleen. Previous studies focused on spleen, where YopM inhibits accumulation of inflammatory dendritic cells. In the present study we focused on liver, where PMN function may be directly undermined by YopM without changes in inflammatory cell numbers in the initial days of infection, and foci of inflammation are easily identified. Mice were infected with parent and ΔyopM-1 Y. pestis KIM5, and effects of YopM were assessed by immunohistochemistry and determinations of bacterial viable numbers in organs. The bacteria were found associated with myeloid cells in foci of inflammation and in liver sinusoids. A new in-vivo phenotype of YopM was revealed: death of inflammatory cells, evidenced by TUNEL staining beginning at d 1 of infection. Based on distributions of Ly6G(+, F4/80(+, and iNOS(+ cells within foci, the cells that were killed could have included both PMNs and macrophages. By 2 d post-infection, YopM had no effect on distribution of these cells, but by 3 d cellular decomposition had outstripped acute inflammation in foci due to parent Y. pestis, while foci due to the ΔyopM-1 strain still contained many inflammatory cells. The destruction depended on the presence of both PMNs in the mice and YopM in the bacteria. In mice that lacked the apoptosis mediator caspase-3 the infection dynamics were novel: the parent Y. pestis was limited in growth comparably to the ΔyopM-1 strain in liver, and in spleen a partial growth limitation for parent Y. pestis was seen. This result identified caspase-3 as a co-factor or effector in YopM's action and supports the hypothesis that in liver YopM's main pathogenic effect is mediated by caspase-3 to cause apoptosis of PMNs.

  5. Advances in sepsis-associated liver dysfunction

    OpenAIRE

    Wang, Dawei; Yin, Yimei; Yao, Yongming

    2014-01-01

    Recent studies have revealed liver dysfunction as an early event in sepsis. Sepsis-associated liver dysfunction is mainly resulted from systemic or microcirculatory disturbances, spillovers of bacteria and endotoxin (lipopolysaccharide, LPS), and subsequent activation of inflammatory cytokines as well as mediators. Three main cell types of the liver which contribute to the hepatic response in sepsis are Kupffer cells (KCs), hepatocytes and liver sinusoidal endothelial cells (LSECs). In additi...

  6. Liver spots

    Science.gov (United States)

    ... skin changes - liver spots; Senile or solar lentigines; Skin spots - aging; Age spots ... Liver spots are changes in skin color that occur in older skin. The coloring may be due to aging, exposure to the sun ...

  7. Liver Diseases

    Science.gov (United States)

    Your liver is the largest organ inside your body. It helps your body digest food, store energy, and remove poisons. There are many kinds of liver diseases: Diseases caused by viruses, such as hepatitis ...

  8. Liver disease

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/000205.htm Liver disease To use the sharing features on this page, please enable JavaScript. The term "liver disease" applies to many conditions that stop the ...

  9. T cell-mediated hepatitis in mice infected with lymphocytic choriomeningitis virus. Liver cell destruction by H-2 class I-restricted virus-specific cytotoxic T cells as a physiological correlate of the 51Cr-release assay

    International Nuclear Information System (INIS)

    Zinkernagel, R.M.; Haenseler, E.; Leist, T.; Cerny, A.; Hengartner, H.; Althage, A.

    1986-01-01

    A model for immunologically T cell-mediated hepatitis was established in mice infected with lymphocytic choriomeningitis virus (LCMV). The severity of hepatitis was monitored histologically and by determination of changes in serum levels of the enzymes alanine aminotransferase (ALT), aspartate aminotransferase (AST), glutamate dehydrogenase (GLDH), and alkaline phosphatase (AP). Kinetics of histological disease manifestations, increases of liver enzyme levels in the serum, and cytotoxic T cell activities in livers and spleens all correlated and were dependent upon several parameters: LCMV-isolate; LCMV-WE caused extensive hepatitis, LCMV-Armstrong virtually none. Virus dose. Route of infection; i.v. or i.p. infection caused hepatitis, whereas infection into the footpad did not. The general genetic background of the murine host; of the strains tested, Swiss mice and A-strain mice were more susceptible than C57BL or CBA mice; BALB/c and DBA/2 mice were least susceptible. The degree of immunocompetence of the murine host; T cell deficient nu/nu mice never developed hepatitis, whereas nu/+ or +/+ mice always did. B cell-depleted anti-IgM-treated mice developed immune-mediated hepatitis comparably or even more extensively than control mice. Local cytotoxic T cell activity; mononuclear cells isolated from livers during the period of overt hepatitis were two to five times more active than equal numbers of spleen cells. Adoptive transfer of nylon wool-nonadherent anti-Thy-1.2 and anti-Lyt-2 plus C-sensitive, anti-L3T4 plus C-resistant lymphocytes into irradiated mice preinfected with LCMV-WE caused a rapid time- and dose-dependent linear increase of serum enzyme levels. This increase was caused by adoptive transfer of lymphocytes if immune cell donors and recipient mice shared class I, but not when they shared class II histocompatibility antigens

  10. Supercritical fluid regeneration of adsorbents

    Science.gov (United States)

    Defilippi, R. P.; Robey, R. J.

    1983-05-01

    The results of a program to perform studies supercritical (fluid) carbon dioxide (SCF CO2) regeneration of adsorbents, using samples of industrial wastewaters from manufacturing pesticides and synthetic solution, and to estimate the economics of the specific wastewater treatment regenerations, based on test data are given. Processing costs for regenerating granular activated carbon GAC) for treating industrial wastewaters depend on stream properties and regeneration throughput.

  11. Evidence that estrogen receptors play a limited role in mediating enhanced recovery of bile flow in female rats in the acute phase of liver ischemia reperfusion injury

    NARCIS (Netherlands)

    de Vries, Heleen A. H.; Ponds, Fraukje A. M.; Nieuwenhuijs, Vincent B.; Morphett, Arthur; Padbury, Robert T. A.; Barritt, Greg J.

    2013-01-01

    Introduction. Female patients exhibit better survival and less hepatic damage from ischemia reperfusion (IR) injury following surgery. However, the effects of sex and estrogens on liver function in the acute phase of IR are not well understood. Objective. The aim was to investigate this question.

  12. Impairment of Akt activity by CYP2E1 mediated oxidative stress is involved in chronic ethanol-induced fatty liver

    Directory of Open Access Journals (Sweden)

    Tao Zeng

    2018-04-01

    Full Text Available Protein kinase B (PKB/Akt plays important roles in the regulation of lipid homeostasis, and impairment of Akt activity has been demonstrated to be involved in the development of non-alcoholic fatty liver disease (NAFLD. Previous studies suggest that cytochrome P4502E1 (CYP2E1 plays causal roles in the pathogenesis of alcoholic fatty liver (AFL. We hypothesized that Akt activity might be impaired due to CYP2E1-induced oxidative stress in chronic ethanol-induced hepatic steatosis. In this study, we found that chronic ethanol-induced hepatic steatosis was accompanied with reduced phosphorylation of Akt at Thr308 in mice liver. Chronic ethanol exposure had no effects on the protein levels of phosphatidylinositol 3 kinase (PI3K and phosphatase and tensin homologue deleted on chromosome ten (PTEN, and led to a slight decrease of phosphoinositide-dependent protein kinase 1 (PDK-1 protein level. Ethanol exposure resulted in increased levels of malondialdehyde (MDA and 4-hydroxynonenal (4-HNE-Akt adducts, which was significantly inhibited by chlormethiazole (CMZ, an efficient CYP2E1 inhibitor. Interestingly, N-acetyl-L-cysteine (NAC significantly attenuated chronic ethanol-induced hepatic fat accumulation and the decline of Akt phosphorylation at Thr308. In the in vitro studies, Akt phosphorylation was suppressed in CYP2E1-expressing HepG2 (CYP2E1-HepG2 cells compared with the negative control HepG2 (NC-HepG2 cells, and 4-HNE treatment led to significant decrease of Akt phosphorylation at Thr308 in wild type HepG2 cells. Lastly, pharmacological activation of Akt by insulin-like growth factor-1 (IGF-1 significantly alleviated chronic ethanol-induced fatty liver in mice. Collectively, these results indicate that CYP2E1-induced oxidative stress may be responsible for ethanol-induced suppression of Akt phosphorylation and pharmacological modulation of Akt in liver may be an effective strategy for the treatment of ethanol-induced fatty liver. Keywords

  13. An active magnetic regenerator device

    DEFF Research Database (Denmark)

    2015-01-01

    A rotating active magnetic regenerator (AMR) device comprising two or more regenerator beds, a magnet arrangement and a valve arrangement. The valve arrangement comprises a plurality of valve elements arranged substantially immovably with respect to the regenerator beds along a rotational direction...

  14. Dilong: Role in Peripheral Nerve Regeneration

    Directory of Open Access Journals (Sweden)

    Yung-Ming Chang

    2011-01-01

    Full Text Available Dilong, also known as earthworm, has been widely used in traditional Chinese medicine (TCM for thousands of years. Schwann cell migration and proliferation are critical for the regeneration of injured nerves and Schwann cells provide an essentially supportive role for neuron regeneration. However, the molecular mechanisms of migration and proliferation induced by dilongs in Schwann cells remain unclear. Here, we discuss the molecular mechanisms that includes (i migration signaling, MAPKs (mitogen-activated protein kinases, mediated PAs and MMP2/9 pathway; (ii survival and proliferative signaling, IGF-I (insulin-like growth factor-I-mediated PI3K/Akt pathways and (iii cell cycle regulation. Dilong stimulate RSC96 cell proliferation and migration. It can induce phosphorylation of ERK1/2 and p38, but not JNK, and activate the downstream signaling expression of PAs (plasminogen activators and MMPs (matrix metalloproteinases in a time-dependent manner. In addition, Dilong stimulated ERK1/2 and p38 phosphorylation was attenuated by pretreatment with chemical inhibitors (U0126 and SB203580, and small interfering ERK1/2 and p38 RNA, resulting in migration and uPA-related signal pathway inhibition. Dilong also induces the phosphorylation of IGF-I-mediated PI3K/Akt pathway, activates protein expression of PCNA (proliferating cell nuclear antigen and cell cycle regulatory proteins (cyclin D1, cyclin E and cyclin A in a time-dependent manner. In addition, it accelerates G1-phase progression with earlier S-phase entry and significant numbers of cells entered the S-phase. The siRNA-mediated knockdown of PI3K that significantly reduces PI3K protein expression levels, resulting in Bcl2 survival factor reduction, revealing a marked blockage of G1 to S transition in proliferating cells. These results reveal the unknown RSC96 cell migration and proliferation mechanism induced by dilong, which find use as a new medicine for nerve regeneration.

  15. Infection and Pulp Regeneration

    Directory of Open Access Journals (Sweden)

    Sahng G. Kim

    2016-03-01

    Full Text Available The regeneration of the pulp-dentin complex has been a great challenge to both scientists and clinicians. Previous work has shown that the presence of prior infection may influence the characteristics of tissues formed in the root canal space after regenerative endodontic treatment. The formation of ectopic tissues such as periodontal ligament, bone, and cementum has been observed in the root canal space of immature necrotic teeth with apical periodontitis, while the regeneration of dentin and pulp has been identified in previously non-infected teeth. The current regenerative endodontic therapy utilizes disinfection protocols, which heavily rely on chemical irrigation using conventional disinfectants. From a microbiological point of view, the current protocols may not allow a sufficiently clean root canal microenvironment, which is critical for dentin and pulp regeneration. In this article, the significance of root canal disinfection in regenerating the pulp-dentin complex, the limitations of the current regenerative endodontic disinfection protocols, and advanced disinfection techniques designed to reduce the microorganisms and biofilms in chronic infection are discussed.

  16. Atmospheric pressure plasma accelerates tail regeneration in tadpoles Xenopus laevis

    Science.gov (United States)

    Rivie, A.; Martus, K.; Menon, J.

    2017-08-01

    Atmospheric pressure plasma is a partially ionized gas composed of neutral and charged particles, including electrons and ions, as well as reactive oxygen species (ROS). Recently, it is utilized as possible therapy in oncology, sterilization, skin diseases, wound healing and tissue regeneration. In this study we focused on effect of plasma exposure on tail regeneration of tadpoles, Xenopus leavis with special emphasis on role of ROS, antioxidant defenses and morphological features of the regenerate. When amputated region of the tail was exposed to the helium plasma it resulted in a faster rate of growth, elevated ROS and increase in antioxidant enzymes in the regenerate compared to that of untreated control. An increase in nitric oxide (free radical) as well as activity of nitric oxide synthase(s) were observed once the cells of the regeneration blastema - a mass of proliferating cells are ready for differentiation. Microscopically the cells of the regenerate of plasma treated tadpoles show altered morphology and characteristics of cellular hypoxia and oxidative stress. We summarize that plasma exposure accelerates the dynamics of wound healing and tail regeneration through its effects on cell proliferation and differentiation as well as angiogenesis mediated through ROS signaling.

  17. Hypothalamic kappa opioid receptor mediates both diet-induced and melanin concentrating hormone-induced liver damage through inflammation and endoplasmic reticulum stress.

    Science.gov (United States)

    Imbernon, Monica; Sanchez-Rebordelo, Estrella; Romero-Picó, Amparo; Kalló, Imre; Chee, Melissa J; Porteiro, Begoña; Al-Massadi, Omar; Contreras, Cristina; Fernø, Johan; Senra, Ana; Gallego, Rosalia; Folgueira, Cintia; Seoane, Luisa M; van Gestel, Margriet; Adan, Roger A; Liposits, Zsolt; Dieguez, Carlos; López, Miguel; Nogueiras, Ruben

    2016-10-01

    The opioid system is widely known to modulate the brain reward system and thus affect the behavior of humans and other animals, including feeding. We hypothesized that the hypothalamic opioid system might also control energy metabolism in peripheral tissues. Mice lacking the kappa opioid receptor (κOR) and adenoviral vectors overexpressing or silencing κOR were stereotaxically delivered in the lateral hypothalamic area (LHA) of rats. Vagal denervation was performed to assess its effect on liver metabolism. Endoplasmic reticulum (ER) stress was inhibited by pharmacological (tauroursodeoxycholic acid) and genetic (overexpression of the chaperone glucose-regulated protein 78 kDa) approaches. The peripheral effects on lipid metabolism were assessed by histological techniques and western blot. We show that in the LHA κOR directly controls hepatic lipid metabolism through the parasympathetic nervous system, independent of changes in food intake and body weight. κOR colocalizes with melanin concentrating hormone receptor 1 (MCH-R1) in the LHA, and genetic disruption of κOR reduced melanin concentrating hormone-induced liver steatosis. The functional relevance of these findings was given by the fact that silencing of κOR in the LHA attenuated both methionine choline-deficient, diet-induced and choline-deficient, high-fat diet-induced ER stress, inflammation, steatohepatitis, and fibrosis, whereas overexpression of κOR in this area promoted liver steatosis. Overexpression of glucose-regulated protein 78 kDa in the liver abolished hypothalamic κOR-induced steatosis by reducing hepatic ER stress. This study reveals a novel hypothalamic-parasympathetic circuit modulating hepatic function through inflammation and ER stress independent of changes in food intake or body weight; these findings might have implications for the clinical use of opioid receptor antagonists. (Hepatology 2016;64:1086-1104). © 2016 The Authors. (Hepatology published by Wiley Periodicals, Inc., on

  18. HMGB1 and Extracellular Histones Significantly Contribute to Systemic Inflammation and Multiple Organ Failure in Acute Liver Failure.

    Science.gov (United States)

    Yang, Runkuan; Zou, Xiaoping; Tenhunen, Jyrki; Tønnessen, Tor Inge

    2017-01-01

    Acute liver failure (ALF) is the culmination of severe liver cell injury from a variety of causes. ALF occurs when the extent of hepatocyte death exceeds the hepatic regenerative capacity. ALF has a high mortality that is associated with multiple organ failure (MOF) and sepsis; however, the underlying mechanisms are still not clear. Emerging evidence shows that ALF patients/animals have high concentrations of circulating HMGB1, which can contribute to multiple organ injuries and mediate gut bacterial translocation (BT). BT triggers/induces systemic inflammatory responses syndrome (SIRS), which can lead to MOF in ALF. Blockade of HMGB1 significantly decreases BT and improves hepatocyte regeneration in experimental acute fatal liver injury. Therefore, HMGB1 seems to be an important factor that links BT and systemic inflammation in ALF. ALF patients/animals also have high levels of circulating histones, which might be the major mediators of systemic inflammation in patients with ALF. Extracellular histones kill endothelial cells and elicit immunostimulatory effect to induce multiple organ injuries. Neutralization of histones can attenuate acute liver, lung, and brain injuries. In conclusion, HMGB1 and histones play a significant role in inducing systemic inflammation and MOF in ALF.

  19. HMGB1 and Extracellular Histones Significantly Contribute to Systemic Inflammation and Multiple Organ Failure in Acute Liver Failure

    Directory of Open Access Journals (Sweden)

    Runkuan Yang

    2017-01-01

    Full Text Available Acute liver failure (ALF is the culmination of severe liver cell injury from a variety of causes. ALF occurs when the extent of hepatocyte death exceeds the hepatic regenerative capacity. ALF has a high mortality that is associated with multiple organ failure (MOF and sepsis; however, the underlying mechanisms are still not clear. Emerging evidence shows that ALF patients/animals have high concentrations of circulating HMGB1, which can contribute to multiple organ injuries and mediate gut bacterial translocation (BT. BT triggers/induces systemic inflammatory responses syndrome (SIRS, which can lead to MOF in ALF. Blockade of HMGB1 significantly decreases BT and improves hepatocyte regeneration in experimental acute fatal liver injury. Therefore, HMGB1 seems to be an important factor that links BT and systemic inflammation in ALF. ALF patients/animals also have high levels of circulating histones, which might be the major mediators of systemic inflammation in patients with ALF. Extracellular histones kill endothelial cells and elicit immunostimulatory effect to induce multiple organ injuries. Neutralization of histones can attenuate acute liver, lung, and brain injuries. In conclusion, HMGB1 and histones play a significant role in inducing systemic inflammation and MOF in ALF.

  20. Stimulating endogenous cardiac regeneration

    Directory of Open Access Journals (Sweden)

    Amanda eFinan

    2015-09-01

    Full Text Available The healthy adult heart has a low turnover of cardiac myocytes. The renewal capacity, however, is augmented after cardiac injury. Participants in cardiac regeneration include cardiac myocytes themselves, cardiac progenitor cells, and peripheral stem cells, particularly from the bone marrow compartment. Cardiac progenitor cells and bone marrow stem cells are augmented after cardiac injury, migrate to the myocardium, and support regeneration. Depletion studies of these populations have demonstrated their necessary role in cardiac repair. However, the potential of these cells to completely regenerate the heart is limited. Efforts are now being focused on ways to augment these natural pathways to improve cardiac healing, primarily after ischemic injury but in other cardiac pathologies as well. Cell and gene therapy or pharmacological interventions are proposed mechanisms. Cell therapy has demonstrated modest results and has passed into clinical trials. However, the beneficial effects of cell therapy have primarily been their ability to produce paracrine effects on the cardiac tissue and recruit endogenous stem cell populations as opposed to direct cardiac regeneration. Gene therapy efforts have focused on prolonging or reactivating natural signaling pathways. Positive results have been demonstrated to activate the endogenous stem cell populations and are currently being tested in clinical trials. A potential new avenue may be to refine pharmacological treatments that are currently in place in the clinic. Evidence is mounting that drugs such as statins or beta blockers may alter endogenous stem cell activity. Understanding the effects of these drugs on stem cell repair while keeping in mind their primary function may strike a balance in myocardial healing. To maximize endogenous cardiac regeneration,a combination of these approaches couldameliorate the overall repair process to incorporate the participation ofmultiple cell players.

  1. Quantification of liver fat: A comprehensive review.

    Science.gov (United States)

    Goceri, Evgin; Shah, Zarine K; Layman, Rick; Jiang, Xia; Gurcan, Metin N

    2016-04-01

    Fat accumulation in the liver causes metabolic diseases such as obesity, hypertension, diabetes or dyslipidemia by affecting insulin resistance, and increasing the risk of cardiac complications and cardiovascular disease mortality. Fatty liver diseases are often reversible in their early stage; therefore, there is a recognized need to detect their presence and to assess its severity to recognize fat-related functional abnormalities in the liver. This is crucial in evaluating living liver donors prior to transplantation because fat content in the liver can change liver regeneration in the recipient and donor. There are several methods to diagnose fatty liver, measure the amount of fat, and to classify and stage liver diseases (e.g. hepatic steatosis, steatohepatitis, fibrosis and cirrhosis): biopsy (the gold-standard procedure), clinical (medical physics based) and image analysis (semi or fully automated approaches). Liver biopsy has many drawbacks: it is invasive, inappropriate for monitoring (i.e., repeated evaluation), and assessment of steatosis is somewhat subjective. Qualitative biomarkers are mostly insufficient for accurate detection since fat has to be quantified by a varying threshold to measure disease severity. Therefore, a quantitative biomarker is required for detection of steatosis, accurate measurement of severity of diseases, clinical decision-making, prognosis and longitudinal monitoring of therapy. This study presents a comprehensive review of both clinical and automated image analysis based approaches to quantify liver fat and evaluate fatty liver diseases from different medical imaging modalities. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. ATP Binding cassette transporter gene expression in rat liver progenitor cells

    NARCIS (Netherlands)

    Ros, J.E.; Roskams, T.A.D.; Geuken, M.; Havinga, R.; Splinter, P.L.; Petersen, B.E.; LaRusso, N.F.; Kolk, van der D.M.; Kuipers, F.; Faber, K.N.; Müller, M.R.; Jansen, P.L.M.

    2003-01-01

    Background and aim: Liver regeneration after severe liver damage depends in part on proliferation and differentiation of hepatic progenitor cells (HPCs). Under these conditions they must be able to withstand the toxic milieu of the damaged liver. ATP binding cassette (ABC) transporters are

  3. ATP binding cassette transporter gene expression in rat liver progenitor cells

    NARCIS (Netherlands)

    Ros, J. E.; Roskams, T. A. D.; Geuken, M.; Havinga, R.; Splinter, P. L.; Petersen, B. E.; LaRusso, N. F.; van der Kolk, D. M.; Kuipers, F.; Faber, K. N.; Müller, M.; Jansen, P. L. M.

    2003-01-01

    BACKGROUND AND AIM: Liver regeneration after severe liver damage depends in part on proliferation and differentiation of hepatic progenitor cells (HPCs). Under these conditions they must be able to withstand the toxic milieu of the damaged liver. ATP binding cassette (ABC) transporters are

  4. ATP binding cassette transporter gene expression in rat liver progenitor cells

    NARCIS (Netherlands)

    Ros, J.E.; Roskams, TAD; Geuken, M; Havinga, R; Splinter, PL; Petersen, BE; LaRusso, NF; van der Kolk, D.M.; Kuipers, F; Faber, KN; Muller, M; Jansen, PLM

    Background and aim: Liver regeneration after severe liver damage depends in part on proliferation and differentiation of hepatic progenitor cells (HPCs). Under these conditions they must be able to withstand the toxic milieu of the damaged liver. ATP binding cassette (ABC) transporters are

  5. RB has a critical role in mediating the in vivo checkpoint response, mitigating secondary DNA damage and suppressing liver tumorigenesis initiated by aflatoxin B1

    OpenAIRE

    Reed, CA; Mayhew, CN; McClendon, AK; Yang, X; Witkiewicz, A; Knudsen, ES

    2009-01-01

    Hepatocellular carcinoma (HCC) is a significant worldwide health concern that is associated with discrete etiological events, encompassing viral infection, metabolic stress and genotoxic compounds. In particular, exposure to the genotoxic hepatocarcinogen aflatoxin B1 (AFB1) is a significant factor in the genesis of human liver cancer. Presumably, genetic events associated with HCC could influence the effect of environmental insults, yielding a predilection for tumor development. The retinobl...

  6. Fatty Liver

    International Nuclear Information System (INIS)

    Filippone, A.; Digiovandomenico, V.; Digiovandomenico, E.; Genovesi, N.; Bonomo, L.

    1991-01-01

    The authors report their experience with the combined use of US and CT in the study of diffuse and subtotal fatty infiltration of the liver. An apparent disagreement was initially found between the two examinations in the study of fatty infiltration. Fifty-five patients were studied with US and CT of the upper abdomen, as suggested by clinics. US showed normal liver echogenicity in 30 patients and diffuse increased echogenicity (bright liver) in 25 cases. In 5 patients with bright liver, US demonstrated a solitary hypoechoic area, appearing as a 'skip area', in the quadrate lobe. In 2 patients with bright liver, the hypoechoic area was seen in the right lobe and exhibited no typical US features of 'Skip area'. Bright liver was quantified by measuring CT density of both liver and spleen. The relative attenuation values of spleen and liver were compared on plain and enhanced CT scans. In 5 cases with a hypoechoic area in the right lobe, CT findings were suggestive of hemangioma. A good correlation was found between broght liver and CT attenuation values, which decrease with increasing fat content of the liver. Moreover, CT attenuation values confirmed US findings in the study of typical 'skip area', by demonstrating normal density - which suggests that CT can characterize normal tissue in atypical 'skip area'

  7. A Complex Interplay between Wnt/β-Catenin Signalling and the Cell Cycle in the Adult Liver

    Directory of Open Access Journals (Sweden)

    Angélique Gougelet

    2012-01-01

    Full Text Available Canonical Wnt signalling, governed by its effector β-catenin, is known for a long time as playing an important role in development, tissue homeostasis, and cancer. In the liver, it was unravelled as both an oncogenic pathway involved in a subset of liver cancers and a physiological signalling identified as the “zonation-keeper” of the quiescent liver lobule. This duality has encouraged to explore the role of canonical Wnt in liver regeneration and liver-cell proliferation mainly using murine genetic models of β-catenin overactivation or inactivation. These studies definitely integrate Wnt signalling within the hepatic network driving regeneration and proliferation. We will review here the current knowledge concerning the mitogenic effect of Wnt, to switch on its specific role in the liver, which is quiescent but with a great capacity to regenerate. The duality of β-catenin signalling, associated both with liver quiescence and liver-cell proliferation, will be brought forward.

  8. A Complex Interplay between Wnt/β-Catenin Signalling and the Cell Cycle in the Adult Liver.

    Science.gov (United States)

    Gougelet, Angélique; Colnot, Sabine

    2012-01-01

    Canonical Wnt signalling, governed by its effector β-catenin, is known for a long time as playing an important role in development, tissue homeostasis, and cancer. In the liver, it was unravelled as both an oncogenic pathway involved in a subset of liver cancers and a physiological signalling identified as the "zonation-keeper" of the quiescent liver lobule. This duality has encouraged to explore the role of canonical Wnt in liver regeneration and liver-cell proliferation mainly using murine genetic models of β-catenin overactivation or inactivation. These studies definitely integrate Wnt signalling within the hepatic network driving regeneration and proliferation. We will review here the current knowledge concerning the mitogenic effect of Wnt, to switch on its specific role in the liver, which is quiescent but with a great capacity to regenerate. The duality of β-catenin signalling, associated both with liver quiescence and liver-cell proliferation, will be brought forward.

  9. Efficient in vitro regeneration protocol of Centella asiatica (L.) Urban ...

    African Journals Online (AJOL)

    The present communication reports an efficient in vitro plantlet regeneration protocol for endemic umbellifer Centella asiatica (L.) urban via callus mediated organogenesis from leaf and stem explants. The plant is pharmacologically very important and its consumption as underutilized green leafy vegetable affluent in ...

  10. Comparative liver accumulation of dioxin-like compounds in sheep and cattle: Possible role of AhR-mediated xenobiotic metabolizing enzymes.

    Science.gov (United States)

    Girolami, F; Spalenza, V; Benedetto, A; Manzini, L; Badino, P; Abete, M C; Nebbia, C

    2016-11-15

    PCDDs, PCDFs, and PCBs are persistent organic pollutants (POPs) that accumulate in animal products and may pose serious health problems. Those able to bind the aryl hydrocarbon receptor (AhR), eliciting a plethora of toxic responses, are defined dioxin-like (DL) compounds, while the remainders are called non-DL (NDL). An EFSA opinion has highlighted the tendency of ovine liver to specifically accumulate DL-compounds to a greater extent than any other farmed ruminant species. To examine the possible role in such an accumulation of xenobiotic metabolizing enzymes (XME) involved in DL-compound biotransformation, liver samples were collected from ewes and cows reared in an area known for low dioxin contamination. A related paper reported that sheep livers had about 5-fold higher DL-compound concentrations than cattle livers, while the content of the six marker NDL-PCBs did not differ between species. Specimens from the same animals were subjected to gene expression analysis for AhR, AhR nuclear translocator (ARNT) and AhR-dependent oxidative and conjugative pathways; XME protein expression and activities were also investigated. Both AhR and ARNT mRNA levels were about 2-fold lower in ovine samples and the same occurred for CYP1A1 and CYP1A2, being approximately 3- and 9-fold less expressed in sheep compared to cattle, while CYP1B1 could be detectable in cattle only. The results of the immunoblotting and catalytic activity (most notably EROD) measurements of the CYP1A family enzymes were in line with the gene expression data. By contrast, phase II enzyme expression and activities in sheep were higher (UGT1A) or similar (GSTA1, NQO1) to those recorded in cattle. The overall low expression of CYP1 family enzymes in the sheep is in line with the observed liver accumulation of DL-compounds and is expected to affect the kinetics and the dynamics of other POPs such as many polycyclic aromatic hydrocarbons, as well as of toxins (e.g. aflatoxins) or drugs (e.g. benzimidazole

  11. Loss of c-Met signaling sensitizes hepatocytes to lipotoxicity and induces cholestatic liver damage by aggravating oxidative stress

    International Nuclear Information System (INIS)

    Gomez-Quiroz, Luis E.; Seo, Daekwan; Lee, Yun-Han; Kitade, Mitsuteru; Gaiser, Timo; Gillen, Matthew; Lee, Seung-Bum; Gutierrez-Ruiz, Ma Concepcion; Conner, Elizabeth A.; Factor, Valentina M; Thorgeirsson, Snorri S.; Marquardt, Jens U.

    2016-01-01

    Recent studies confirmed a critical importance of c-Met signaling for liver regeneration by modulating redox balance. Here we used liver-specific conditional knockout mice (MetKO) and a nutritional model of hepatic steatosis to address the role of c-Met in cholesterol-mediated liver toxicity. Liver injury was assessed by histopathology and plasma enzymes levels. Global transcriptomic changes were examined by gene expression microarray, and key molecules involved in liver damage and lipid homeostasis were evaluated by Western blotting. Loss of c-Met signaling amplified the extent of liver injury in MetKO mice fed with high-cholesterol diet for 30 days as evidenced by upregulation of liver enzymes and increased synthesis of total bile acids, aggravated inflammatory response and enhanced intrahepatic lipid deposition. Global transcriptomic changes confirmed the enrichment of networks involved in steatosis and cholestasis. In addition, signaling pathways related to glutathione and lipid metabolism, oxidative stress and mitochondria dysfunction were significantly affected by the loss of c-Met function. Mechanistically, exacerbation of oxidative stress in MetKO livers was corroborated by increased lipid and protein oxidation. Western blot analysis further revealed suppression of Erk, NF-kB and Nrf2 survival pathways and downstream target genes (e.g. cyclin D1, SOD1, gamma-GCS), as well as up-regulation of proapoptotic signaling (e.g. p53, caspase 3). Consistent with the observed steatotic and cholestatic phenotype, nuclear receptors RAR, RXR showed increased activation while expression levels of CAR, FXR and PPAR-alpha were decreased in MetKO. Collectively, our data provide evidence for the critical involvement of c-Met signaling in cholesterol and bile acids toxicity.

  12. Urinary proteomic profiling reveals diclofenac-induced renal injury and hepatic regeneration in mice

    Energy Technology Data Exchange (ETDEWEB)

    Swelm, Rachel P.L. van [Department of Pharmacology and Toxicology, Radboud University Nijmegen Medical Centre, P.O. Box 9101, 6500 HB Nijmegen (Netherlands); Laarakkers, Coby M.M. [Department of Laboratory Medicine, Radboud University Nijmegen Medical Centre, P.O. Box 9101, 6500 HB Nijmegen (Netherlands); Pertijs, Jeanne C.L.M.; Verweij, Vivienne; Masereeuw, Rosalinde [Department of Pharmacology and Toxicology, Radboud University Nijmegen Medical Centre, P.O. Box 9101, 6500 HB Nijmegen (Netherlands); Russel, Frans G.M., E-mail: F.Russel@pharmtox.umcn.nl [Department of Pharmacology and Toxicology, Radboud University Nijmegen Medical Centre, P.O. Box 9101, 6500 HB Nijmegen (Netherlands)

    2013-06-01

    Diclofenac (DF) is a widely used non-steroidal anti-inflammatory drug for the treatment of rheumatic disorders, but is often associated with liver injury. We applied urinary proteomic profiling using MALDI-TOF MS to identify biomarkers for DF-induced hepatotoxicity in mice. Female CH3/HeOUJIco mice were treated with 75 mg/kg bw DF by oral gavage and 24 h urine was collected. Proteins identified in urine of DF-treated mice included epidermal growth factor, transthyretin, kallikrein, clusterin, fatty acid binding protein 1 and urokinase, which are related to liver regeneration but also to kidney injury. Both organs showed enhanced levels of oxidative stress (TBARS, p < 0.01). Kidney injury was confirmed by histology and increased Kim1 and Il-6 mRNA expression levels (p < 0.001 and p < 0.01). Liver histology and plasma ALT levels in DF-treated mice were not different from control, but mRNA expression of Stat3 (p < 0.001) and protein expression of PCNA (p < 0.05) were increased, indicating liver regeneration. In conclusion, urinary proteome analysis revealed that DF treatment in mice induced kidney and liver injury. Within 24 h, however, the liver was able to recover by activating tissue regeneration processes. Hence, the proteins found in urine of DF-treated mice represent kidney damage rather than hepatic injury. - Highlights: • The urinary proteome shows biological processes involved in adverse drug reactions. • Urine proteins of DF-treated mice relate to kidney injury rather than liver injury. • Liver regeneration, not liver injury, is apparent 24h after oral DF administration. • Pretreatment with LPS does not enhance DF-induced liver injury in mice.

  13. Bionanomaterials for skin regeneration

    CERN Document Server

    Leonida, Mihaela D

    2016-01-01

    This book gives a concise overview of bionanomaterials with applications for skin regeneration. The advantages and challenges of nanoscale materials are covered in detail, giving a basic view of the skin structure and conditions that require transdermal or topical applications. Medical applications, such as wound healing, care for burns, skin disease, and cosmetic care, such as aging of the skin and photodamage, and how they benefit from bionanomaterials, are described in detail. A final chapter is devoted to the ethical and social issues related to the use of bionanomaterials for skin regeneration. This is an ideal book for researchers in materials science, medical scientists specialized in dermatology, and cosmetic chemists working in formulations. It can also serve as a reference for nanotechnologists, dermatologists, microbiologists, engineers, and polymer chemists, as well as students studying in these fields.

  14. Biomaterials for cardiac regeneration

    CERN Document Server

    Ruel, Marc

    2015-01-01

    This book offers readers a comprehensive biomaterials-based approach to achieving clinically successful, functionally integrated vasculogenesis and myogenesis in the heart. Coverage is multidisciplinary, including the role of extracellular matrices in cardiac development, whole-heart tissue engineering, imaging the mechanisms and effects of biomaterial-based cardiac regeneration, and autologous bioengineered heart valves. Bringing current knowledge together into a single volume, this book provides a compendium to students and new researchers in the field and constitutes a platform to allow for future developments and collaborative approaches in biomaterials-based regenerative medicine, even beyond cardiac applications. This book also: Provides a valuable overview of the engineering of biomaterials for cardiac regeneration, including coverage of combined biomaterials and stem cells, as well as extracellular matrices Presents readers with multidisciplinary coverage of biomaterials for cardiac repair, including ...

  15. On the postradiation effect of cystamine in rat liver cells

    International Nuclear Information System (INIS)

    Gil'yano, N.Ya.; Malinovskij, O.V.

    1979-01-01

    The effect of cystamine, classical radioprotector introduced prior to and after irradiation has been tested. The protector has been paralelly tested on the regenerating liver in a presynthetic phase of a mitotic cycle (G 1 ). White nonbred male mice have been irradiated with 205 and 6O5 rad on the RUM-11 X-ray apparatus prior to (intact liver) and 6 hours after (regenerating liver) partial hepatectomy. Cystamine has been injected to animals 15 min prior to irradiation and in different periods after irradiation in the concentration of 150 mg/kg of weight. The decrease in the share of cells with asymmetic chromosome transformations (bridges and fragments in the anaphase) has been the protector effectiveness index. It is shown that the protector is effective in the cells of a regenerating liver only when introduced before irradiation, while in the cells of an intact liver it produces a protective effect both prior to and 15 mins after irradiation. Cystamine effectiveness for cells of the intact and regenerating liver has been investigated by introducing it after irradiation of animals with 250 and 305 rad. It has been established that the protector makes it possible to modify the irradiation effect within 20 mins after irradiation in the cells of the intact liver (Go). Cystamine postradiation protection in the cells of the regenerating liver (G 1 ) is low if it is introduced immediately after irradiation (1 min) and is absent after 10 min. The dependence of cystamine postradiation protective effect on the moment of liver cell stimulation has been investigated. It has been shown that the modification of irradiation effect is possible within 5 hrs after irradiation if the protector is introduced 15 min after irradiation of animals with 250 rad. The mechanism of the preparation action is discussed

  16. Estimation of ellagic acid and/or repaglinide effects on insulin signaling, oxidative stress, and inflammatory mediators of liver, pancreas, adipose tissue, and brain in insulin resistant/type 2 diabetic rats.

    Science.gov (United States)

    Amin, Mohamed M; Arbid, Mahmoud S

    2017-02-01

    Even though ellagic acid has previously been valued in many models of cancer, so far its full mechanistic effect as a natural antiapoptotic agent in the prevention of type 2 diabetes complications has not been completely elucidated, which was the goal of this study. We fed albino rats a high-fat fructose diet (HFFD) for 2 months to induce insulin resistance/type 2 diabetes and then treated the rats with ellagic acid (10 mg/kg body weight, orally) and/or repaglinide (0.5 mg/kg body weight, orally) for 2 weeks. At the serum level, ellagic acid challenged the consequences of HFFD, significantly improving the glucose/insulin balance, liver enzymes, lipid profile, inflammatory cytokines, redox level, adipokines, ammonia, and manganese. At the tissue level (liver, pancreas, adipose tissue, and brain), ellagic acid significantly enhanced insulin signaling, autophosphorylation, adiponectin receptors, glucose transporters, inflammatory mediators, and apoptotic markers. Remarkably, combined treatment with both ellagic acid and repaglinide had a more pronounced effect than treatment with either alone. These outcomes give new insight into the promising molecular mechanisms by which ellagic acid modulates numerous factors induced in the progression of diabetes.

  17. Uptake of oleate by isolated rat adipocytes is mediated by a 40-kDa plasma membrane fatty acid binding protein closely related to that in liver and gut

    International Nuclear Information System (INIS)

    Schwieterman, W.; Sorrentino, D.; Potter, B.J.; Rand, J.; Kiang, C.L.; Stump, D.; Berk, P.D.

    1988-01-01

    A portion of the hepatocellular uptake of nonesterified long-chain fatty acids is mediated by a specific 40-kDa plasma membrane fatty acid binding protein, which has also been isolated from the gut. To investigate whether a similar transport process exists in other tissues with high transmembrane fatty acid fluxes, initial rates (V/sub O/) of [ 3 H]-oleate uptake into isolated rat adipocytes were studied as a function of the concentration of unbound [ 3 H]oleate in the medium. V/sub O/ reached a maximum as the concentration of unbound oleate was increased and was significantly inhibited both by phloretin and by prior incubation of the cells with Pronase. A rabbit antibody to the rat liver plasma membrane fatty acid binding protein inhibited adipocyte fatty acid uptake by up to 63% in dose-dependent fashion. Inhibition was noncompetitive; at an immunoglobulin concentration of 250 μg/ml V/sub max/ was reduced from 2480 /plus minus/ 160 to 1870 /plus minus/ 80 pmol/min per 5 /times/ 10 4 adipocytes, with no change in K/sub m/. A basic kDa adipocyte plasma membrane fatty acid binding protein, isolated from crude adipocyte plasma membrane fractions, reacted strongly in both agar gel diffusion and electrophoretic blots with the antibody raised against the corresponding hepatic plasma membrane protein. These data indicate that the uptake of oleate by rat adipocytes is mediated by a 40-kDa plasma membrane fatty acid binding protein closely related to that in liver and gut

  18. Nrf2-mediated antioxidant response by ethanolic extract of Sida cordifolia provides protection against alcohol-induced oxidative stress in liver by upregulation of glutathione metabolism.

    Science.gov (United States)

    Rejitha, S; Prathibha, P; Indira, M

    2015-03-01

    Obje