Science.gov

Sample records for increased liver regeneration

  1. Liver regeneration.

    PubMed

    Mao, Shennen A; Glorioso, Jaime M; Nyberg, Scott L

    2014-04-01

    The liver is unique in its ability to regenerate in response to injury. A number of evolutionary safeguards have allowed the liver to continue to perform its complex functions despite significant injury. Increased understanding of the regenerative process has significant benefit in the treatment of liver failure. Furthermore, understanding of liver regeneration may shed light on the development of cancer within the cirrhotic liver. This review provides an overview of the models of study currently used in liver regeneration, the molecular basis of liver regeneration, and the role of liver progenitor cells in regeneration of the liver. Specific focus is placed on clinical applications of current knowledge in liver regeneration, including small-for-size liver transplant. Furthermore, cutting-edge topics in liver regeneration, including in vivo animal models for xenogeneic human hepatocyte expansion and the use of decellularized liver matrices as a 3-dimensional scaffold for liver repopulation, are proposed. Unfortunately, despite 50 years of intense study, many gaps remain in the scientific understanding of liver regeneration.

  2. Liver Regeneration

    PubMed Central

    Mao, Shennen A; Glorioso, Jaime M; Nyberg, Scott L

    2014-01-01

    The liver is unique in its ability to regenerate in response to injury. A number of evolutionary safeguards have allowed the liver to continue to perform its complex functions despite significant injury. Increased understanding of the regenerative process has significant benefit in the treatment of liver failure. Furthermore, understanding of liver regeneration may shed light on the development of cancer within the cirrhotic liver. This review will provide an overview of the models of study currently utilized in liver regeneration, the molecular basis of liver regeneration, and the role of liver progenitor cells in regeneration of the liver. Specific focus will be placed on clinical applications of current knowledge in liver regeneration including small for size liver transplant. Furthermore, cutting edge topics in liver regeneration including in vivo animal models for xenogeneic human hepatocyte expansion and the use of decellularized liver matrices as a three dimensional scaffold for liver repopulation will be proposed. Unfortunately, despite 50 years of intense study, many gaps remain in the scientific understanding of liver regeneration. PMID:24495569

  3. Liver Regeneration

    PubMed Central

    Michalopoulos, George K.

    2009-01-01

    Liver regeneration after partial hepatectomy is a very complex and well-orchestrated phenomenon. It is carried out by the participation of all mature liver cell types. The process is associated with signaling cascades involving growth factors, cytokines, matrix remodeling, and several feedbacks of stimulation and inhibition of growth related signals. Liver manages to restore any lost mass and adjust its size to that of the organism, while at the same time providing full support for body homeostasis during the entire regenerative process. In situations when hepatocytes or biliary cells are blocked from regeneration, these cell types can function as facultative stem cells for each other. PMID:17559071

  4. Transforming growth factor beta mRNA increases during liver regeneration: a possible paracrine mechanism of growth regulation.

    PubMed Central

    Braun, L; Mead, J E; Panzica, M; Mikumo, R; Bell, G I; Fausto, N

    1988-01-01

    Transforming growth factor beta (TGF-beta) is a growth factor with multiple biological properties including stimulation and inhibition of cell proliferation. To determine whether TGF-beta is involved in hepatocyte growth responses in vivo, we measured the levels of TGF-beta mRNA in normal liver and during liver regeneration after partial hepatectomy in rats. TGF-beta mRNA increases in the regenerating liver and reaches a peak (about 8 times higher than basal levels) after the major wave of hepatocyte cell division and mitosis have taken place and after the peak expression of the ras protooncogenes. Although hepatocytes from normal and regenerating liver respond to TGF-beta, they do not synthesize TGF-beta mRNA. Instead, the message is present in liver nonparenchymal cells and is particularly abundant in cell fractions enriched for endothelial cells. TGF-beta inhibits epidermal growth factor-induced DNA synthesis in vitro in hepatocytes from normal or regenerating liver, although the dose-response curves vary according to the culture medium used. We conclude that TGF-beta may function as the effector of an inhibitory paracrine loop that is activated during liver regeneration, perhaps to prevent uncontrolled hepatocyte proliferation. Images PMID:3422749

  5. Stem Cells and Liver Regeneration

    PubMed Central

    DUNCAN, ANDREW W.; DORRELL, CRAIG; GROMPE, MARKUS

    2011-01-01

    One of the defining features of the liver is the capacity to maintain a constant size despite injury. Although the precise molecular signals involved in the maintenance of liver size are not completely known, it is clear that the liver delicately balances regeneration with overgrowth. Mammals, for example, can survive surgical removal of up to 75% of the total liver mass. Within 1 week after liver resection, the total number of liver cells is restored. Moreover, liver overgrowth can be induced by a variety of signals, including hepatocyte growth factor or peroxisome proliferators; the liver quickly returns to its normal size when the proliferative signal is removed. The extent to which liver stem cells mediate liver regeneration has been hotly debated. One of the primary reasons for this controversy is the use of multiple definitions for the hepatic stem cell. Definitions for the liver stem cell include the following: (1) cells responsible for normal tissue turnover, (2) cells that give rise to regeneration after partial hepatectomy, (3) cells responsible for progenitor-dependent regeneration, (4) cells that produce hepatocyte and bile duct epithelial phenotypes in vitro, and (5) transplantable liver-repopulating cells. This review will consider liver stem cells in the context of each definition. PMID:19470389

  6. Telocytes in liver regeneration: possible roles.

    PubMed

    Wang, Fei; Song, Yang; Bei, Yihua; Zhao, Yingying; Xiao, Junjie; Yang, Changqing

    2014-09-01

    Telocytes (TCs) are a novel type of interstitial cells which are potentially involved in tissue regeneration and repair (www.telocytes.com). Previously, we documented the presence of TCs in liver. However, the possible roles of TCs in liver regeneration remain unknown. In this study, a murine model of partial hepatectomy (PH) was used to induce liver regeneration. The number of TCs detected by double labelling immunofluorescence methods (CD34/PDGFR-α, CD34/PDGFR-ß and CD34/Vimentin) was significantly increased when a high level of hepatic cell proliferation rate (almost doubled) as shown by 5-ethynyl-2'-deoxyuridine (EdU) immunostaining and Western Blot of Proliferating cell nuclear antigen (PCNA) was found at 48 and 72 hrs post-PH. Meanwhile, the number of CK-19 positive-hepatic stem cells peaked at 72 hrs post-PH, co-ordinating with the same time-point, when the number of TCs was most significantly increased. Taken together, the results indicate a close relationship between TCs and the cells essentially involved in liver regeneration: hepatocytes and stem cells. It remains to be determined how TCs affect hepatocytes proliferation and/or hepatic stem cell differentiation in liver regeneration. Besides intercellular junctions, we may speculate a paracrine effect via ectovesicles.

  7. Multiple Doses of Erythropoietin Impair Liver Regeneration by Increasing TNF-α, the Bax to Bcl-xL Ratio and Apoptotic Cell Death

    PubMed Central

    Cantré, Daniel; Abshagen, Kerstin; Menger, Michael D.; Vollmar, Brigitte

    2008-01-01

    Background Liver resection and the use of small-for-size grafts are restricted by the necessity to provide a sufficient amount of functional liver mass. Only few promising strategies to maximize liver regeneration are available. Apart from its erythropoiesis-stimulating effect, erythropoietin (EPO) has meanwhile been recognized as mitogenic, tissue-protective, and anti-apoptotic pleiotropic cytokine. Thus, EPO may support regeneration of hepatic tissue. Methodology Rats undergoing 68% hepatectomy received daily either high dose (5000 IU/kg bw iv) or low dose (500 IU/kg bw iv) recombinant human EPO or equal amounts of physiologic saline. Parameters of liver regeneration and hepatocellular apoptosis were assessed at 24 h, 48 h and 5 d after resection. In addition, red blood cell count, hematocrit and serum EPO levels as well as plasma concentrations of TNF-α and IL-6 were evaluated. Further, hepatic Bcl-xL and Bax protein expression were analyzed by Western blot. Principal Findings Administration of EPO significantly reduced the expression of PCNA at 24 h followed by a significant decrease in restitution of liver mass at day 5 after partial hepatectomy. EPO increased TNF-α levels and shifted the Bcl-xL to Bax ratio towards the pro-apoptotic Bax resulting in significantly increased hepatocellular apoptosis. Conclusions Multiple doses of EPO after partial hepatectomy increase hepatocellular apoptosis and impair liver regeneration in rats. Thus, careful consideration should be made in pre- and post-operative recombinant human EPO administration in the setting of liver resection and transplantation. PMID:19079544

  8. Liver growth factor induces testicular regeneration in EDS-treated rats and increases protein levels of class B scavenger receptors.

    PubMed

    Lobo, M V T; Arenas, M I; Huerta, L; Sacristán, S; Pérez-Crespo, M; Gutiérrez-Adán, A; Díaz-Gil, J J; Lasunción, M A; Martín-Hidalgo, A

    2015-01-15

    The aim of the present work was to determine the effects of liver growth factor (LGF) on the regeneration process of rat testes after chemical castration induced by ethane dimethanesulfonate (EDS) by analyzing some of the most relevant proteins involved in cholesterol metabolism, such as hormone sensitive lipase (HSL), 3β-hydroxysteroid dehydrogenase (3β-HSD), scavenger receptor SR-BI, and other components of the SR family that could contribute to the recovery of steroidogenesis and spermatogenesis in the testis. Sixty male rats were randomized to nontreated (controls) and LGF-treated, EDS-treated, and EDS + LGF-treated groups. Testes were obtained on days 10 (T1), 21 (T2), and 35 (T3) after EDS treatment, embedded in paraffin, and analyzed by immunohistochemistry and Western blot. LGF improved the recovery of the seminiferous epithelia, the appearance of the mature pattern of Leydig cell interstitial distribution, and the expression of mature SR-BI. Moreover, LGF treatment resulted in partial recovery of HSL expression in Leydig cells and spermatogonia. No changes in serum testosterone were observed in control or LGF-treated rats, but in EDS-castrated animals LGF treatment induced a progressive increase in serum testosterone levels and 3β-HSD expression. Based on the pivotal role of SR-BI in the uptake of cholesteryl esters from HDL, it is suggested that the observed effects of LGF would facilitate the provision of cholesterol for sperm cell growth and Leydig cell recovery.

  9. Bile acid signaling and liver regeneration.

    PubMed

    Fan, Mingjie; Wang, Xichun; Xu, Ganyu; Yan, Qingfeng; Huang, Wendong

    2015-02-01

    The liver is able to regenerate itself in response to partial hepatectomy or liver injury. This is accomplished by a complex network of different cell types and signals both inside and outside the liver. Bile acids (BAs) are recently identified as liver-specific metabolic signals and promote liver regeneration by activating their receptors: Farnesoid X Receptor (FXR) and G-protein-coupled BA receptor 1 (GPBAR1, or TGR5). FXR is a member of the nuclear hormone receptor superfamily of ligand-activated transcription factors. FXR promotes liver regeneration after 70% partial hepatectomy (PHx) or liver injury. Moreover, activation of FXR is able to alleviate age-related liver regeneration defects. Both liver- and intestine-FXR are activated by BAs after liver resection or injury and promote liver regeneration through distinct mechanism. TGR5 is a membrane-bound BA receptor and it is also activated during liver regeneration. TGR5 regulates BA hydrophobicity and stimulates BA excretion in urine during liver regeneration. BA signaling thus represents a novel metabolic pathway during liver regeneration. This article is part of a Special Issue entitled: Nuclear receptors in animal development.

  10. Clinical implications of advances in liver regeneration.

    PubMed

    Kwon, Yong Jin; Lee, Kyeong Geun; Choi, Dongho

    2015-03-01

    Remarkable advances have been made recently in the area of liver regeneration. Even though liver regeneration after liver resection has been widely researched, new clinical applications have provided a better understanding of the process. Hepatic damage induces a process of regeneration that rarely occurs in normal undamaged liver. Many studies have concentrated on the mechanism of hepatocyte regeneration following liver damage. High mortality is usual in patients with terminal liver failure. Patients die when the regenerative process is unable to balance loss due to liver damage. During disease progression, cellular adaptations take place and the organ microenvironment changes. Portal vein embolization and the associating liver partition and portal vein ligation for staged hepatectomy are relatively recent techniques exploiting the remarkable progress in understanding liver regeneration. Living donor liver transplantation is one of the most significant clinical outcomes of research on liver regeneration. Another major clinical field involving liver regeneration is cell therapy using adult stem cells. The aim of this article is to provide an outline of the clinical approaches being undertaken to examine regeneration in liver diseases.

  11. Circulating Extracellular RNA Markers of Liver Regeneration

    PubMed Central

    Yan, Irene K.; Wang, Xue; Asmann, Yan W.; Haga, Hiroaki; Patel, Tushar

    2016-01-01

    Background and Aims Although a key determinant of hepatic recovery after injury is active liver regeneration, the ability to detect ongoing regeneration is lacking. The restoration of liver mass after hepatectomy involves systemic changes with coordinated changes in gene expression guiding regenerative responses, activation of progenitor cells, and proliferation of quiescent hepatocytes. We postulated that these responses involve intercellular communication involving extracellular RNA and that these could represent biomarkers of active regenerative responses. Methods RNA sequencing was performed to identify temporal changes in serum extracellular non-coding RNA after partial hepatectomy in C57BL/6 male mice. Tissue expression of selected RNA was performed by microarray analysis and validated using qRT-PCR. Digital PCR was used to detect and quantify serum expression of selected RNA. Results A peak increase in extracellular RNA content occurred six hours after hepatectomy. RNA sequencing identified alterations in several small non-coding RNA including known and novel microRNAs, snoRNAs, tRNA, antisense and repeat elements after partial hepatectomy. Combinatorial effects and network analyses identified signal regulation, protein complex assembly, and signal transduction as the most common biological processes targeted by miRNA that altered. miR-1A and miR-181 were most significantly altered microRNA in both serum and in hepatic tissues, and their presence in serum was quantitated using digital PCR. Conclusions Extracellular RNA selectively enriched during acute regeneration can be detected within serum and represent biomarkers of ongoing liver regeneration in mice. The ability to detect ongoing active regeneration would improve the assessment of hepatic recovery from liver injury. PMID:27415797

  12. Rodent models and imaging techniques to study liver regeneration.

    PubMed

    Wei, Weiwei; Dirsch, Olaf; Mclean, Anna Lawson; Zafarnia, Sara; Schwier, Michael; Dahmen, Uta

    2015-01-01

    The liver has the unique capability of regeneration from various injuries. Different animal models and in vitro methods are used for studying the processes and mechanisms of liver regeneration. Animal models were established either by administration of hepatotoxic chemicals or by surgical approach. The administration of hepatotoxic chemicals results in the death of liver cells and in subsequent hepatic regeneration and tissue repair. Surgery includes partial hepatectomy and portal vein occlusion or diversion: hepatectomy leads to compensatory regeneration of the remnant liver lobe, whereas portal vein occlusion leads to atrophy of the ipsilateral lobe and to compensatory regeneration of the contralateral lobe. Adaptation of modern radiological imaging technologies to the small size of rodents made the visualization of rodent intrahepatic vascular anatomy possible. Advanced knowledge of the detailed intrahepatic 3D anatomy enabled the establishment of refined surgical techniques. The same technology allows the visualization of hepatic vascular regeneration. The development of modern histological image analysis tools improved the quantitative assessment of hepatic regeneration. Novel image analysis tools enable us to quantify reliably and reproducibly the proliferative rate of hepatocytes using whole-slide scans, thus reducing the sampling error. In this review, the refined rodent models and the newly developed imaging technology to study liver regeneration are summarized. This summary helps to integrate the current knowledge of liver regeneration and promises an enormous increase in hepatological knowledge in the near future.

  13. Rodent models and imaging techniques to study liver regeneration.

    PubMed

    Wei, Weiwei; Dirsch, Olaf; Mclean, Anna Lawson; Zafarnia, Sara; Schwier, Michael; Dahmen, Uta

    2015-01-01

    The liver has the unique capability of regeneration from various injuries. Different animal models and in vitro methods are used for studying the processes and mechanisms of liver regeneration. Animal models were established either by administration of hepatotoxic chemicals or by surgical approach. The administration of hepatotoxic chemicals results in the death of liver cells and in subsequent hepatic regeneration and tissue repair. Surgery includes partial hepatectomy and portal vein occlusion or diversion: hepatectomy leads to compensatory regeneration of the remnant liver lobe, whereas portal vein occlusion leads to atrophy of the ipsilateral lobe and to compensatory regeneration of the contralateral lobe. Adaptation of modern radiological imaging technologies to the small size of rodents made the visualization of rodent intrahepatic vascular anatomy possible. Advanced knowledge of the detailed intrahepatic 3D anatomy enabled the establishment of refined surgical techniques. The same technology allows the visualization of hepatic vascular regeneration. The development of modern histological image analysis tools improved the quantitative assessment of hepatic regeneration. Novel image analysis tools enable us to quantify reliably and reproducibly the proliferative rate of hepatocytes using whole-slide scans, thus reducing the sampling error. In this review, the refined rodent models and the newly developed imaging technology to study liver regeneration are summarized. This summary helps to integrate the current knowledge of liver regeneration and promises an enormous increase in hepatological knowledge in the near future. PMID:25402256

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

    SciTech Connect

    Obayashi, Yoko; Campbell, Jean S.; Fausto, Nelson; Yeung, Raymond S.

    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.

  15. Sialyltransferase activity in regenerating rat liver

    PubMed Central

    Serafini-Cessi, Franca

    1977-01-01

    Liver microsomal fractions catalyse the transfer of sialic acid from CMP-N-acetyl-neuraminic acid to various exogenous acceptors such as desialylated fetuin, desialylated human Tamm–Horsfall glycoprotein and desialylated bovine submaxillary-gland mucin. An increase in the rate of incorporation of sialic acid into desialylated glycoproteins was found after a lag period (7h) in regenerating liver. The increase was maximum 24h after partial hepatectomy for all acceptors tested. At later times after operation the sialyltransferase activity remained high only for desialylated fetuin. No soluble factors from liver or serum of partially hepatectomized animals influenced the activity of the sialyltransferases bound to the microsomal fraction. The sensitivity of sialyltransferases to activation by Triton X-100, added to the incubation medium, was unchanged in the microsomal preparation from animals 24h after sham operation or partial hepatectomy. The full activity of sialyltransferases towards the various desialylated acceptors showed some differences. Human Tamm–Horsfall glycoprotein was a good acceptor of sialic acid only when desialylated by mild acid hydrolysis. After this treatment, but not after enzymic hydrolysis, a decrease in molecular weight of human Tamm–Horsfall glycoprotein was observed. Further, the sialyltransferase activity as a function of incubation temperature gave different curves according to the acceptor used. The relationship between the biosynthesis of glycoproteins by regenerating liver and the sialyltransferase activity of microsomal fraction after partial hepatectomy is discussed. PMID:597233

  16. Tityus: a forgotten myth of liver regeneration.

    PubMed

    Tiniakos, Dina G; Kandilis, Apostolos; Geller, Stephen A

    2010-08-01

    The ancient Greek myth of Tityus is related to liver regeneration in the same way as the well known myth of Prometheus is. Depictions of the punishment of Prometheus are frequently used by lecturers on liver regeneration; however, Tityus remains unknown despite the fact that he received the same punishment and his myth could also be used as a paradigm for the organ's extraordinary ability to regenerate. Nevertheless, there is no convincing evidence that ancient Greeks had any specific knowledge about liver regeneration, a concept introduced in the early 19th century. We describe and analyze the myth of Tityus and compare it to the myth of Prometheus. We also explore artistic and literary links and summarize recent scientific data on the mechanisms of liver regeneration. Finally, we highlight links of the legend of Tityus with other sciences.

  17. Tityus: a forgotten myth of liver regeneration.

    PubMed

    Tiniakos, Dina G; Kandilis, Apostolos; Geller, Stephen A

    2010-08-01

    The ancient Greek myth of Tityus is related to liver regeneration in the same way as the well known myth of Prometheus is. Depictions of the punishment of Prometheus are frequently used by lecturers on liver regeneration; however, Tityus remains unknown despite the fact that he received the same punishment and his myth could also be used as a paradigm for the organ's extraordinary ability to regenerate. Nevertheless, there is no convincing evidence that ancient Greeks had any specific knowledge about liver regeneration, a concept introduced in the early 19th century. We describe and analyze the myth of Tityus and compare it to the myth of Prometheus. We also explore artistic and literary links and summarize recent scientific data on the mechanisms of liver regeneration. Finally, we highlight links of the legend of Tityus with other sciences. PMID:20472318

  18. Elucidating the metabolic regulation of liver regeneration.

    PubMed

    Huang, Jiansheng; Rudnick, David A

    2014-02-01

    The regenerative capability of liver is well known, and the mechanisms that regulate liver regeneration are extensively studied. Such analyses have defined general principles that govern the hepatic regenerative response and implicated specific extracellular and intracellular signals as regulated during and essential for normal liver regeneration. Nevertheless, the most proximal events that stimulate liver regeneration and the distal signals that terminate this process remain incompletely understood. Recent data suggest that the metabolic response to hepatic insufficiency might be the proximal signal that initiates regenerative hepatocellular proliferation. This review provides an overview of the data in support of a metabolic model of liver regeneration and reflects on the clinical implications and areas for further study suggested by these findings.

  19. Deceleration of liver regeneration by knockdown of augmenter of liver regeneration gene is associated with impairment of mitochondrial DNA synthesis in mice.

    PubMed

    Han, Li-hong; Dong, Ling-yue; Yu, Hao; Sun, Guang-yong; Wu, Yuan; Gao, Jian; Thasler, Wolfgang; An, Wei

    2015-07-15

    Hepatic stimulator substance, also known as augmenter of liver regeneration (ALR), is a novel hepatic mitogen that stimulates liver regeneration after partial hepatectomy (PH). Recent work has indicated that a lack of ALR expression inhibited liver regeneration in rats, and the mechanism seems to be related to increased cell apoptosis. The mitochondria play an important role during liver regeneration. Adequate ATP supply, which is largely dependent on effective mitochondrial biogenesis, is essential for progress of liver regeneration. However, ALR gene expression during liver regeneration, particularly its function with mitochondrial DNA synthesis, remains poorly understood. In this study, ALR expression in hepatocytes of mice was suppressed with ALR short-hairpin RNA interference or ALR deletion (knockout, KO). The ALR-defective mice underwent PH, and the liver was allowed to regenerate for 1 wk. Analysis of liver growth and its correlation with mitochondrial biogenesis showed that both ALR mRNA and protein levels increased robustly in control mice with a maximum at days 3 and 4 post-PH. However, ALR knockdown inhibited hepatic DNA synthesis and decelerated liver regeneration after PH. Furthermore, both in the ALR-knockdown and ALR-KO mice, expression of mitochondrial transcription factor A and peroxisome proliferator-activated receptor-γ coactivator-1α were reduced, resulting in impaired mitochondrial biogenesis. In conclusion, ALR is apparently required to ensure appropriate liver regeneration following PH in mice, and deletion of the ALR gene may delay liver regeneration in part due to impaired mitochondrial biogenesis.

  20. Amiodarone as an autophagy promoter reduces liver injury and enhances liver regeneration and survival in mice after partial hepatectomy

    PubMed Central

    Lin, Chih-Wen; Chen, Yaw-Sen; Lin, Chih-Che; Chen, Yun-Ju; Lo, Gin-Ho; Lee, Po-Huang; Kuo, Po-Lin; Dai, Chia-Yen; Huang, Jee-Fu; Chung, Wang-Long; Yu, Ming-Lung

    2015-01-01

    The deregulation of autophagy is involved in liver regeneration. Here, we investigated the role of autophagy in the regulation of liver regeneration after partial hepatectomy (PHx) and the development of pharmacological interventions for improved liver regeneration after PHx. We show that autophagy was activated in the early stages of liver regeneration following 70% PHx in vivo. Moreover, amiodarone was associated with a significant enhancement of autophagy, liver growth, and hepatocyte proliferation, along with reduced liver injury and the termination of liver regeneration due to decreased transforming growth factor-β1 expression after 70% PHx. The promotion of autophagy appeared to selectively increase the removal of damaged mitochondria. We also found that Atg7 knockdown or pretreatment with chloroquine aggravated the liver injury associated with 70% PHx and reduced liver growth and hepatocyte proliferation. Finally, amiodarone improved liver regeneration, survival, and liver injury after 90% PHx. In conclusion, our results indicate that autophagy plays an important role in mouse liver regeneration and that modulating autophagy with amiodarone may be an effective method of improving liver regeneration, increasing survival, and ameliorating liver injury following PHx. PMID:26515640

  1. Amiodarone as an autophagy promoter reduces liver injury and enhances liver regeneration and survival in mice after partial hepatectomy.

    PubMed

    Lin, Chih-Wen; Chen, Yaw-Sen; Lin, Chih-Che; Chen, Yun-Ju; Lo, Gin-Ho; Lee, Po-Huang; Kuo, Po-Lin; Dai, Chia-Yen; Huang, Jee-Fu; Chung, Wang-Long; Yu, Ming-Lung

    2015-10-30

    The deregulation of autophagy is involved in liver regeneration. Here, we investigated the role of autophagy in the regulation of liver regeneration after partial hepatectomy (PHx) and the development of pharmacological interventions for improved liver regeneration after PHx. We show that autophagy was activated in the early stages of liver regeneration following 70% PHx in vivo. Moreover, amiodarone was associated with a significant enhancement of autophagy, liver growth, and hepatocyte proliferation, along with reduced liver injury and the termination of liver regeneration due to decreased transforming growth factor-β1 expression after 70% PHx. The promotion of autophagy appeared to selectively increase the removal of damaged mitochondria. We also found that Atg7 knockdown or pretreatment with chloroquine aggravated the liver injury associated with 70% PHx and reduced liver growth and hepatocyte proliferation. Finally, amiodarone improved liver regeneration, survival, and liver injury after 90% PHx. In conclusion, our results indicate that autophagy plays an important role in mouse liver regeneration and that modulating autophagy with amiodarone may be an effective method of improving liver regeneration, increasing survival, and ameliorating liver injury following PHx.

  2. Increasing FCC regenerator catalyst level

    SciTech Connect

    Wong, R.F. )

    1993-11-01

    A Peruvian FCC unit's operations were improved by increasing the regenerator's catalyst level. This increase resulted in lower stack losses, an improved temperature profile, increased catalyst activity and a lower catalyst consumption rate. A more stable operation saved this Peruvian refiner over $131,000 per year in catalyst alone. These concepts and data may be suitable for your FCC unit as well.

  3. Human C1 inhibitor attenuates liver ischemia-reperfusion injury and promotes liver regeneration.

    PubMed

    Saidi, Reza F; Rajeshkumar, Barur; Shariftabrizi, Ahmad; Dresser, Karen; Walter, Otto

    2014-04-01

    Liver ischemia-reperfusion injury (IRI) is a well-known cause of morbidity and mortality after liver transplantation (LT). Activation of the complement system contributes to the pathogenesis of IRI. Effective treatment strategies aimed at reducing hepatic IRI and accelerating liver regeneration could offer major benefits in LT. Herein, we investigated the effect of C1-esterase inhibitor (human) [C1-INH] on IRI and liver regeneration. Mice were subjected to 60-min partial IRI, with or without 70% partial hepatectomy, or CCl4-induced acute liver failure. Before liver injury, the animals were pretreated with intravenous C1-INH or normal saline. Liver IRI was evaluated using serum levels of alanine aminotransferase, serum interleukin-6, and histopathology. Liver samples were stained for specific markers of regeneration (5-bromo-2'-deoxyuridine [BrdU] staining and proliferating cell nuclear antigen [PCNA]). Histology, serum interleukin-6, and alanine aminotransferase release revealed that C1-INH treatment attenuated liver injury compared with controls. Improved animal survival and increased number of BrdU- and PCNA-positive cells were observed in C1-INH-treated animals which underwent IRI + partial hepatectomy or CCl4 injection compared with control group. These data indicate that complement plays a key role in IRI and liver regeneration. C1-INH represents a potential therapeutic strategy to reduce IRI and promote regeneration in LT.

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

    SciTech Connect

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

    2009-03-13

    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.

  5. FAK deletion accelerates liver regeneration after two-thirds partial hepatectomy

    PubMed Central

    Shang, Na; Arteaga, Maribel; Chitsike, Lennox; Wang, Fang; Viswakarma, Navin; Breslin, Peter; Qiu, Wei

    2016-01-01

    Understanding the molecular mechanisms of liver regeneration is essential to improve the survival rate of patients after surgical resection of large amounts of liver tissue. Focal adhesion kinase (FAK) regulates different cellular functions, including cell survival, proliferation and cell migration. The role of FAK in liver regeneration remains unknown. In this study, we found that Fak is activated and induced during liver regeneration after two-thirds partial hepatectomy (PHx). We used mice with liver-specific deletion of Fak and investigated the role of Fak in liver regeneration in 2/3 PHx model (removal of 2/3 of the liver). We found that specific deletion of Fak accelerates liver regeneration. Fak deletion enhances hepatocyte proliferation prior to day 3 post-PHx but attenuates hepatocyte proliferation 3 days after PHx. Moreover, we demonstrated that the deletion of Fak in liver transiently increases EGFR activation by regulating the TNFα/HB-EGF axis during liver regeneration. Furthermore, we found more apoptosis in Fak-deficient mouse livers compared to WT mouse livers after PHx. Conclusion: Our data suggest that Fak is involved in the process of liver regeneration, and inhibition of FAK may be a promising strategy to accelerate liver regeneration in recipients after liver transplantation. PMID:27677358

  6. Regulation of fibronectin expression in rat regenerating liver.

    PubMed Central

    Caputi, M; Melo, C A; Baralle, F E

    1995-01-01

    Fibronectin (FN) expression displays a complex regulation that results in precisely defined isoform patterns during different developmental stages, ageing and injury. The qualitative and quantitative changes that are observed derive from modulation of the rate of transcription of the single FN pre-mRNA and its specific differential processing in the EIIIA, EIIIB and V regions of rat FN. The liver is the major source of plasma FN which is characterised by the absence of the EIIIA and EIIIB exons. Here we show that in the rat regenerating liver there is a significant reprogramming of the splicing machinery that results in the synthesis by the liver of up to 17% of EIIIA+ FN linked with all the three V forms. On the other hand the EIIIB+ form is totally absent both in normal and regenerating liver. Furthermore there is a variation of the V pattern observed in the regenerating tissue, the V120 form (linked to both EIIIA+ and EIIIA- messengers) increases from 11 to 32%. The quantitative RT-PCR method was used to estimate the FN transcription rate, before and after partial hepatectomy. We have shown a 3-fold increase in FN mRNA in liver that is specifically linked to the regeneration process and not to the surgical stress. Images PMID:7862527

  7. Liver regeneration - mechanisms and models to clinical application.

    PubMed

    Forbes, Stuart J; Newsome, Philip N

    2016-08-01

    Liver regeneration has been studied for many decades and the mechanisms underlying regeneration of the normal liver following resection or moderate damage are well described. A large number of factors extrinsic (such as bile acids and circulating growth factors) and intrinsic to the liver interact to initiate and regulate liver regeneration. Less well understood, and more clinically relevant, are the factors at play when the abnormal liver is required to regenerate. Fatty liver disease, chronic scarring, prior chemotherapy and massive liver injury can all inhibit the normal programme of regeneration and can lead to liver failure. Understanding these mechanisms could enable the rational targeting of specific therapies to either reduce the factors inhibiting regeneration or directly stimulate liver regeneration. Although animal models of liver regeneration have been highly instructive, the clinical relevance of some models could be improved to bridge the gap between our in vivo model systems and the clinical situation. Likewise, modern imaging techniques such as spectroscopy will probably improve our understanding of whole-organ metabolism and how this predicts the liver's regenerative capacity. This Review describes briefly the mechanisms underpinning liver regeneration, the models used to study this process, and discusses areas in which failed or compromised liver regeneration is clinically relevant. PMID:27353402

  8. Sinusoidal communication in liver fibrosis and regeneration.

    PubMed

    Marrone, Giusi; Shah, Vijay H; Gracia-Sancho, Jordi

    2016-09-01

    Cellular crosstalk is a process through which a message is transmitted within an individual cell (intracellular crosstalk) or between different cells (intercellular crosstalk). Intercellular crosstalk within the liver microenvironment is critical for the maintenance of normal hepatic functions and for cells survival. Hepatic cells are closely connected to each other, work in synergy, and produce molecules that modulate their differentiation and activity. This review summarises the current knowledge regarding paracrine communication networks in parenchymal and non-parenchymal cells in liver fibrosis due to chronic injury, and regeneration after partial hepatectomy. PMID:27151183

  9. Bacterial clearance in the intact and regenerating liver

    SciTech Connect

    Gross, K.; Katz, S.; Dunn, S.P.; Cikrit, D.; Rosenthal, R.; Grosfeld, J.L.

    1985-08-01

    The Kupffer cells in the liver play an important role in reticuloendothelial system (RES) function by clearing particulate matter and bacteria from the blood stream. While hepatocyte regeneration and function have been extensively studied following partial hepatectomy, little information is available concerning RES function in the regenerating liver. This study investigates hepatic RES function by evaluating bacterial clearance (live E. coli) in the intact and regenerating liver. Thirty-four young male Sprague Dawley rats were studied. Twenty-two animals underwent a standard 70% partial hepatectomy using ligature technique and 12 had a sham operation. Both groups of rats received 10(9) organism of TVS labeled E coli, intravenously at 24 hours, 72 hours, 2 1/2 weeks, and 6 weeks postoperatively. Rats were killed 10 minutes following injection and liver, lung, spleen, and kidney harvested, fixed, and radioactivity was determined using a scintillation spectrometer interfaced with a micro-computer counting the TVS radiolabel. The total organ count of trapped bacteria in liver in partially hepatectomized rats was lower than intact controls at 24 hours, but was similar at 72 hours, 2 1/2 weeks, and 6 weeks. Partial hepatectomy increased the amount of bacterial trapping in the lung at 24 hours and 72 hours and returned to normal at 2 1/2 weeks and 6 weeks. Splenic activity was increased following hepatectomy at 2 1/2 weeks. Renal clearance was increased at 72 hours and 2 1/2 weeks.

  10. [Effect of autophagy on liver regeneration].

    PubMed

    Qiwen, Wang; Cuifang, Chang; Ningning, Gu; Cuiyun, Pan; Cunshuan, Xu

    2015-11-01

    Autophagy is a lysosome-mediated degradation pathway, which plays an important role in hepatic physiological and pathological processes, in eukaryotic cells. The liver has a remarkable regenerative capacity. After acute or chronic injury, the residual hepatic cells can be activated to enter the cell-cycle for proliferation, in order to compensate for lost liver tissue and recover liver function. In this review, we summarize the relationship between liver regeneration (LR) after various types of injury and autophagy. For example, autophagy is activated to accelerate LR after physically, alcohol and food borne induced liver injury, while the role of autophagy in animal models of LR after chemical injury remains controversial. Autophagy can also be used to promote the replication of virus particles by some hepatotropic viruses (e.g., HBV, HCV) and inhibit LR after viral infection. Studies on mechanisms of autophagy and LR will contribute to clarify the regenerative process and provide new methods for the treatment of liver disease. PMID:26582525

  11. Liver repopulation and regeneration: new approaches to old questions

    PubMed Central

    Duncan, Andrew W.; Soto-Gutierrez, Alejandro

    2013-01-01

    Purpose of review Significant recent developments have occurred in the field of liver regeneration. Although the regenerative response to partial hepatectomy has been studied extensively, in recent years the use of new experimental approaches has incorporated a fresh look that may lead to a better understanding of hepatocyte dysfunction and regeneration. Recent findings Liver injury promotes the regenerative responses that are relatively rare in healthy livers. Current research efforts focus on the mechanisms of hepatocyte adaptation in response to liver injury. We will discuss how hepatic aneuploidy and polyploidy contributes to liver regeneration, as well as new modalities to study cellular interactions using the organ-specific microenvironment. Summary High mortality is generally limited to patients who develop terminal liver failure, which occurs when regenerative responses are unable to compensate for liver injury. Cellular adaptations and organ microenvironment changes are present during disease processes. This review aims to provide insights into the innovative approaches taken to investigate regeneration in liver diseases. PMID:23425785

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

    SciTech Connect

    Cimica, Velasco . E-mail: vcimica@aecom.yu.edu; Batusic, Danko; Haralanova-Ilieva, Borislava; Chen, Yonglong; Hollemann, Thomas; Pieler, Tomas; Ramadori, Giuliano

    2007-08-31

    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.

  13. Cilostazol improves hepatic blood perfusion, microcirculation, and liver regeneration after major hepatectomy in rats.

    PubMed

    von Heesen, Maximilian; Dold, Stefan; Müller, Simon; Scheuer, Claudia; Kollmar, Otto; Schilling, Martin K; Menger, Michael D; Moussavian, Mohammed R

    2015-06-01

    Major hepatectomy or small-for-size liver transplantation may result in postoperative liver failure. So far, no treatment is available to improve liver regeneration. Herein, we studied whether cilostazol, a selective phosphodiesterase III inhibitor, is capable of improving liver regeneration after major hepatectomy. Sprague-Dawley rats (n = 74) were treated with cilostazol (5 mg/kg daily) or a glucose solution and underwent either 70% liver resection or a sham operation. Before and after surgery, hepatic arterial and portal venous blood flow and hepatic microvascular perfusion were analyzed. Liver morphology, function, and regeneration were studied with histology, immunohistochemistry, western blotting, and bile excretion analysis. Cilostazol significantly increased hepatic blood flow and microcirculation before and after hepatectomy in comparison with sham-operated controls. This was associated with an elevation of hepatic vascular endothelial growth factor expression, an increase of hepatocellular proliferation, and an acceleration of liver regeneration. Furthermore, cilostazol protected the tissue of the remnant liver as indicated by an attenuation of hepatocellular disintegration. In conclusion, cilostazol increases hepatic blood perfusion, microcirculation, and liver regeneration after a major hepatectomy. Thus, cilostazol may represent a novel strategy to reduce the rate of liver failure after both extended hepatectomy and small-for-size liver transplantation.

  14. Effects of hypergravity on rat liver regeneration

    NASA Technical Reports Server (NTRS)

    Feller, D. D.

    1982-01-01

    The effects of centrifugation on liver regrowth were examined by measuring mitotic activity. The results indicate that the increased gravity caused a delay in the onset of mitotic activity and a significant decrease in overall mitotic activity.

  15. Liver regeneration after living donor transplant

    PubMed Central

    Olthoff, Kim M.; Emond, Jean C.; Shearon, Tempie H.; Everson, Greg; Baker, Talia B.; Fisher, Robert A.; Freise, Chris E.; Gillespie, Brenda W.; Everhart, James E.

    2014-01-01

    Background & Aims Adult-to-adult living donors and recipients were studied to characterize patterns of liver growth and identify associated factors in a multicenter study. Methods 350 donors and 353 recipients in A2ALL (Adult to Adult Living Donor Liver Transplantation Cohort Study) transplanted between March 2003 and February 2010 were included. Potential predictors of 3-month liver volume included total and standard liver volumes (TLV, SLV), the model for end-stage liver disease (MELD) score (in recipients), remnant and graft size, remnant to donor and graft to recipient weight ratio (RDWR, GRWR), remnant/TLV, and graft/SLV. Results Among donors, 3-month absolute growth was 676±251g (mean± SD) and percent reconstitution was 80%±13%. Among recipients, GRWR was 1.3%±0.4% (8<0.8%). Graft weight was 60%±13% of SLV. Three-month absolute growth was 549±267g and percent reconstitution was 93%±18%. Predictors of greater 3-month liver volume included larger patient size (donors, recipients), larger graft volume (recipients), and larger TLV (donors). Donors with the smallest remnant/TLV ratios had larger than expected growth, but also had higher postoperative bilirubin and international normalized ratio at 7 and 30 days. In a combined donor-recipient analysis, donors had smaller 3-month liver volumes than recipients adjusted for patient size, remnant or graft volume, and TLV or SLV (p=0.004). Recipient graft failure in the first 90 days was predicted by poor graft function at day 7 (HR=4.50, p=0.001), but not by GRWR or graft fraction (p>0.90 for each). Conclusions Both donors and recipients had rapid yet incomplete restoration of tissue mass in the first 3 months, confirming previous reports. Recipients achieved a greater percentage of expected total volume. Patient size and recipient graft volume significantly influenced 3 month volumes. Importantly, donor liver volume is a critical predictor of the rate of regeneration, and donor remnant fraction impacts post

  16. Nicotinamide nucleotide synthesis in regenerating rat liver

    PubMed Central

    Ferris, G. M.; Clark, J. B.

    1971-01-01

    1. The concentrations and total content of the nicotinamide nucleotides were measured in the livers of rats at various times after partial hepatectomy and laparotomy (sham hepatectomy) and correlated with other events in the regeneration process. 2. The NAD content and concentration in rat liver were relatively unaffected by laparotomy, but fell to a minimum, 25 and 33% below control values respectively, 24h after partial hepatectomy. NADP content and concentration were affected similarly by both laparotomy and partial hepatectomy, falling rapidly and remaining depressed for up to 48h. 3. The effect of injecting various doses of nicotinamide on the liver DNA and NAD 18h after partial hepatectomy was studied and revealed an inverse correlation between NAD content and DNA content. 4. Injections of nicotinamide at various times after partial hepatectomy revealed that the ability to synthesize NAD from nicotinamide was impaired during the first 12h, rose to a peak at 26h and fell again by 48h after partial hepatectomy. 5. The total liver activity of NAD pyrophosphorylase (EC 2.7.7.1) remained at or slightly above the initial value for 12h after partial hepatectomy and then rose continuously until 48h after operation. The activity of NMN pyrophosphorylase (EC 2.4.2.12) showed a similar pattern of change after partial hepatectomy, but was at no time greater than 5% of the activity of NAD pyrophosphorylase. 6. The results are discussed with reference to the control of NAD synthesis in rapidly dividing tissue. It is suggested that the availability of cofactors and substrates for NAD synthesis is more important as a controlling factor than the maximum enzyme activities. It is concluded that the low concentrations of nicotinamide nucleotides in rapidly dividing tissues are the result of competition between NAD synthesis and nucleic acid synthesis for common precursor and cofactors. PMID:4398891

  17. Laminin and Fibronectin in Cell Adhesion: Enhanced Adhesion of Cells from Regenerating Liver to Laminin

    NASA Astrophysics Data System (ADS)

    Carlsson, Roland; Engvall, Eva; Freeman, Aaron; Ruoslahti, Erkki

    1981-04-01

    Laminin, a basement membrane glycoprotein isolated from cultures of mouse endodermal cells and rat yolk sac carcinoma cells, promoted the attachment of liver cells obtained from regenerating mouse liver. Cells from normal mouse liver attached readily to dishes coated with fibronectin but attached poorly to surfaces coated with laminin. Both proteins efficiently promoted the attachment of cells from livers undergoing regeneration. After regeneration, the attachment to laminin returned to the low levels found in animals not subjected to partial hepatectomy but attachment to fibronectin remained high. Immunofluorescent staining of sections of normal liver with antilaminin revealed the presence of laminin in or adjacent to the walls of the bile ducts and blood vessels. After induction of regeneration by partial hepatectomy, increased amounts of laminin appeared in the sinusoidal areas. After carbon tetrachloride poisoning, staining for laminin was especially pronounced in the necrotic and postnecrotic areas around the central veins. This additional expression of laminin was transient. It reached a maximum around 5-6 days after the injury and then gradually disappeared. These findings show that laminin is an adhesive protein. The increase of laminin in regenerating liver and the adhesiveness of cells from such livers to laminin suggest a role for laminin in the maintenance of a proper tissue organization during liver regeneration.

  18. SOCS2 Balances Metabolic and Restorative Requirements during Liver Regeneration.

    PubMed

    Masuzaki, Ryota; Zhao, Sophia; Valerius, M Todd; Tsugawa, Daisuke; Oya, Yuki; Ray, Kevin C; Karp, Seth J

    2016-02-12

    After significant injury, the liver must maintain homeostasis during the regenerative process. We hypothesized the existence of mechanisms to limit hepatocyte proliferation after injury to maintain metabolic and synthetic function. A screen for candidates revealed suppressor of cytokine signaling 2 (SOCS2), an inhibitor of growth hormone (GH) signaling, was strongly induced after partial hepatectomy. Using genetic deletion and administration of various factors we investigated the role of SOCS2 during liver regeneration. SOCS2 preserves liver function by restraining the first round of hepatocyte proliferation after partial hepatectomy by preventing increases in growth hormone receptor (GHR) via ubiquitination, suppressing GH pathway activity. At later times, SOCS2 enhances hepatocyte proliferation by modulating a decrease in serum insulin-like growth factor 1 (IGF-1) that allows GH release from the pituitary. SOCS2, therefore, plays a dual role in modulating the rate of hepatocyte proliferation. In particular, this is the first demonstration of an endogenous mechanism to limit hepatocyte proliferation after injury.

  19. Liver regeneration in rats administered high levels of carbohydrates.

    PubMed

    Gershbein, L L

    1976-01-01

    Partially hepatectomized male rats were administered high levels of carbohydrates by drinker, in a casein-cellulose synthetic medium and in a commercial meal over a period of 10 days after surgery and the amount of liver regenerating or the increment ascertained; representative hepatic glycogen changes were also followed. Of the carbohydrate solutions, 5% levulose, 5% levulose+5% glucose and 10% sucrose increased the extent of liver regeneration as was also the case with the synthetic diet suplemented with 30 and 60% glucose, 30 and 60% levulose, 30% levulose+30% glucose, 30% each of galactose and the arabinoglactan, Stractan and 60% each of sucrose, honey and unsulphured molasses. The liver increments and glycogen contents were in the control range for animals fed the synthetic diet containing 30% each of lactose, sorbitol, corn starch and raffinose pentahydrate, 5% ascorbic acid and 15% L-arabinose but the liver glycogen was depressed with 30% xylose, a diet which was poorly tolerated; 15% mannitol caused a decrease inthe increment. The incorporation of several sugars into the commercial rat meal, including xylose (11%), raffinose (15%), L-arabinose (8%), D-arabinose (5%), L-sorbose (17%), galactosamine (0.20%) and galactono-gamma-lactone (10%), led to little change over the control increments. In intact rats fed the synthetic diet containing 30% each of glucose, lactose, galactose, sucrose and levulose for an interval of 10 days, the wet and dry liver--body weight ratios were significantly elevated only with the last two sugars but liver glycogen was increased in each instance.

  20. Bone marrow-derived progenitor cells in de novo liver regeneration in liver transplant.

    PubMed

    Lee, Sung-Gyu; Moon, Sung-Hwan; Kim, Hee-Je; Lee, Ji Yoon; Park, Soon-Jung; Chung, Hyung-Min; Ha, Tae-Yong; Song, Gi-Won; Jung, Dong-Hwan; Park, Hojong; Kwon, Tae-Won; Cho, Yong-Pil

    2015-09-01

    The study was designed (1) to examine the hypothesis that circulating progenitor cells play a role in the process of de novo regeneration in human liver transplants and that these cells arise from a cell population originating in, or associated with, the bone marrow and (2) to investigate whether the transplanted liver volume has an effect on the circulating recipient-derived progenitor cells that generate hepatocytes during this process. Clinical data and liver tissue characteristics were analyzed in male individuals who underwent sex-mismatched adult-to-adult living donor liver transplantation using dual left lobe grafts. Dual left lobe grafts were examined at the time of transplantation and 19 to 27 days after transplantation. All recipients showed recovery of normal liver function and a significant increase in the volume of the engrafted left lobes after transplantation. Double staining for a Y-chromosome probe and the CD31 antigen showed the presence of hybrid vessels composed of recipient-derived cells and donor cells within the transplanted liver tissues. Furthermore, CD34-expressing cells were observed commingling with Y-chromosome+ cells. The ratio of recipient-derived vessels and the number of Y+ CD34+ cells tended to be higher when smaller graft volumes underwent transplantation. These findings suggest that the recruitment of circulating bone marrow-derived progenitor cells could contribute to vessel formation and de novo regeneration in human liver transplants. Moreover, graft volume may be an important determinant for the active mobilization of circulating recipient-derived progenitor cells and their contribution to liver regeneration.

  1. Characterization of the Regulation and Function of Zinc-Dependent Histone Deacetylases During Mouse Liver Regeneration

    PubMed Central

    Huang, Jiansheng; Barr, Emily; Rudnick, David A.

    2013-01-01

    The studies reported here were undertaken to define the regulation and functional importance of zinc-dependent histone deacetylase (Zn-HDAC) activity during liver regeneration using the mouse partial hepatectomy (PH) model. The results showed that hepatic HDAC activity was significantly increased in nuclear and cytoplasmic fractions following PH. Further analyses showed isoform-specific effects of PH on HDAC mRNA and protein expression, with increased expression of the class I HDACs, 1 and 8, and class II HDAC4 in regenerating liver. Hepatic expression of (class II) HDAC5 was unchanged after PH; however HDAC5 exhibited transient nuclear accumulation in regenerating liver. These changes in hepatic HDAC expression, subcellular localization, and activity coincided with diminished histone acetylation in regenerating liver. The significance of these events was investigated by determining the effects of suberoylanilide hydroxyamic acid (SAHA, a specific inhibitor of Zn-HDAC activity) on hepatic regeneration. The results showed that SAHA-treatment suppressed the effects of PH on histone deacetylation and hepatocellular BrdU incorporation. Further examination showed that SAHA blunted hepatic expression and activation of cell cycle signals downstream of induction of cyclin D1 expression in mice subjected to PH. Conclusion The data reported here demonstrate isoform-specific regulation of Zn-HDAC expression, subcellular localization, and activity in regenerating liver. These studies also indicate that HDAC activity promotes liver regeneration by regulating hepatocellular cell cycle progression at a step downstream of cyclin D1 induction. PMID:23258575

  2. Protein tyrosine phosphatase of liver regeneration-1 is required for normal timing of cell cycle progression during liver regeneration.

    PubMed

    Jiao, Yang; Ye, Diana Z; Li, Zhaoyu; Teta-Bissett, Monica; Peng, Yong; Taub, Rebecca; Greenbaum, Linda E; Kaestner, Klaus H

    2015-01-15

    Protein tyrosine phosphatase of liver regeneration-1 (Prl-1) is an immediate-early gene that is significantly induced during liver regeneration. Several in vitro studies have suggested that Prl-1 is important for the regulation of cell cycle progression. To evaluate its function in liver regeneration, we ablated the Prl-1 gene specifically in mouse hepatocytes using the Cre-loxP system. Prl-1 mutant mice (Prl-1(loxP/loxP);AlfpCre) appeared normal and fertile. Liver size and metabolic function in Prl-1 mutants were comparable to controls, indicating that Prl-1 is dispensable for liver development, postnatal growth, and hepatocyte differentiation. Mutant mice demonstrated a delay in DNA synthesis after 70% partial hepatectomy, although ultimate liver mass restoration was not affected. At 40 h posthepatectomy, reduced protein levels of the cell cycle regulators cyclin E, cyclin A2, cyclin B1, and cyclin-dependent kinase 1 were observed in Prl-1 mutant liver. Investigation of the major signaling pathways involved in liver regeneration demonstrated that phosphorylation of protein kinase B (AKT) and signal transducer and activator of transcription (STAT) 3 were significantly reduced at 40 h posthepatectomy in Prl-1 mutants. Taken together, this study provides evidence that Prl-1 is required for proper timing of liver regeneration after partial hepatectomy. Prl-1 promotes G1/S progression via modulating expression of several cell cycle regulators through activation of the AKT and STAT3 signaling pathway.

  3. Protein tyrosine phosphatase of liver regeneration-1 is required for normal timing of cell cycle progression during liver regeneration

    PubMed Central

    Jiao, Yang; Ye, Diana Z.; Li, Zhaoyu; Teta-Bissett, Monica; Peng, Yong; Taub, Rebecca; Greenbaum, Linda E.

    2014-01-01

    Protein tyrosine phosphatase of liver regeneration-1 (Prl-1) is an immediate-early gene that is significantly induced during liver regeneration. Several in vitro studies have suggested that Prl-1 is important for the regulation of cell cycle progression. To evaluate its function in liver regeneration, we ablated the Prl-1 gene specifically in mouse hepatocytes using the Cre-loxP system. Prl-1 mutant mice (Prl-1loxP/loxP;AlfpCre) appeared normal and fertile. Liver size and metabolic function in Prl-1 mutants were comparable to controls, indicating that Prl-1 is dispensable for liver development, postnatal growth, and hepatocyte differentiation. Mutant mice demonstrated a delay in DNA synthesis after 70% partial hepatectomy, although ultimate liver mass restoration was not affected. At 40 h posthepatectomy, reduced protein levels of the cell cycle regulators cyclin E, cyclin A2, cyclin B1, and cyclin-dependent kinase 1 were observed in Prl-1 mutant liver. Investigation of the major signaling pathways involved in liver regeneration demonstrated that phosphorylation of protein kinase B (AKT) and signal transducer and activator of transcription (STAT) 3 were significantly reduced at 40 h posthepatectomy in Prl-1 mutants. Taken together, this study provides evidence that Prl-1 is required for proper timing of liver regeneration after partial hepatectomy. Prl-1 promotes G1/S progression via modulating expression of several cell cycle regulators through activation of the AKT and STAT3 signaling pathway. PMID:25377314

  4. Galectin-1 is essential for efficient liver regeneration following hepatectomy

    PubMed Central

    Potikha, Tamara; Ella, Ezra; Cerliani, Juan P.; Mizrahi, Lina; Pappo, Orit; Rabinovich, Gabriel A.; Galun, Eithan; Goldenberg, Daniel S.

    2016-01-01

    Galectin-1 (Gal1) is a known immune/inflammatory regulator which acts both extracellularly and intracellularly, modulating innate and adaptive immune responses. Here, we explored the role of Gal1 in liver regeneration using 70% partial hepatectomy (PHx) of C57BL/6 wild type and Gal1-knockout (Gal1-KO, Lgals1−/−) mice. Gene or protein expression, in liver samples collected at time intervals from 2 to 168 hours post-operation, was tested by either RT-PCR or by immunoblotting and immunohistochemistry, respectively. We demonstrated that Gal1 transcript and protein expression was induced in the liver tissue of wild type mice upon PHx. Liver regeneration following PHx was significantly delayed in the Gal1-KO compared to the control liver. This delay was accompanied by a decreased Akt phosphorylation, and accumulation of the hepatocyte nuclear p21 protein in the Gal1-KO versus control livers at 24 and 48 hours following PHx. Transcripts of several known regulators of inflammation, cell cycle and cell signaling, including some known PHx-induced genes, were aberrantly expressed (mainly down-regulated) in Gal1-KO compared to control livers at 2, 6 and 24 hours post-PHx. Transient steatosis, which is imperative for liver regeneration following PHx, was significantly delayed and decreased in the Gal1-KO compared to the control liver and was accompanied by a significantly decreased expression in the mutant liver of several genes encoding lipid metabolism regulators. Our results demonstrate that Gal1 protein is essential for efficient liver regeneration following PHx through the regulation of liver inflammation, hepatic cell proliferation, and the control of lipid storage in the regenerating liver. PMID:27166189

  5. Hepatic Progenitor Cells in Action: Liver Regeneration or Fibrosis?

    PubMed

    Kaur, Savneet; Siddiqui, Hamda; Bhat, Mohsin H

    2015-09-01

    Liver injury caused by drugs, viruses, and toxins that impede the proliferation of mature hepatocytes results in the activation of hepatic progenitor cells (HPCs), which then participate in the restoration of the damaged liver tissue. HPCs are known to be bipotential cells, capable of forming both hepatocytes and cholangiocytes when regeneration by mature hepatocytes is plagued or impaired. Both clinical studies of liver disease and certain experimental animal models of liver injury conspicuously show the presence of activated HPC response and proliferation. However, in addition to regeneration, the proliferation of HPCs also determines the appearance of a ductular reaction that has been correlated with progressive portal fibrosis, suggesting intricate links between activation of HPCs and fibrogenesis. The current review highlights the role of activated HPCs in both hepatic regeneration and fibrosis during liver injury.

  6. Role of splanchnic hemodynamics in liver regeneration after living donor liver transplantation.

    PubMed

    Jiang, Shui-Ming; Zhou, Guang-Wen; Zhang, Rui; Peng, Cheng-Hong; Yan, Ji-Qi; Wan, Liang; Shen, Chuan; Chen, Hao; Li, Qing-Yu; Shen, Bai-Yong; Li, Hong-Wei

    2009-09-01

    The aim of this study was to investigate the changes in splanchnic hemodynamics after LDLT and their relationship with graft regeneration. Eighteen patients with LDLT December 2006 and June 2008 were enrolled, and color Doppler ultrasonography was performed preoperatively and on postoperative days (PODs) 1, 3, 5, 7, 30, and 90 after transplantation. The changes in the portal blood flow mean velocity (PBV) and portal blood flow volume (PBF) were monitored, and their effects on hepatic function were observed simultaneously. Graft sizes were measured on PODs 7, 30, and 90 after the operation. The regeneration rates of grafts were calculated. PBF increased in the recipient group from 1081.17 +/- 277.50 to 2171.44 +/- 613.15 mL/minute, and PBV increased from 15.01 +/- 5.67 to 56.00 +/- 22.11 cm/s; they were both significantly higher than those in the donor group (P < 0.01). On POD 1, serum aspartic aminotransferase, alanine aminotransferase, and total bilirubin all peaked; however, these indices in patients with PBF/graft weight (GW) > 300 mL/minute . 100 g were significantly higher than those in patients with PBF/GW < 300 mL/minute . 100 g. Livers in the recipient group regenerated rapidly. The graft regeneration rate reached 119.40% +/- 28.21% as early as 1 month post-transplantation. PBF and PBV on PODs 1 and 3 were greatly related to liver regeneration at 30 days. The portal venous flow in patients with portal hypertension after LDLT showed a high perfusion state, which could promote graft regeneration, but PBF/GW after the operation should be controlled below 300 mL/minute . 100 g in order to protect grafts from hyperperfusion injury.

  7. [Regulation of autophagy on dendritic cells during rat liver regeneration by IPA].

    PubMed

    Qiwen, Wang; Wei, Jin; Cuifang, Chang; Cunshuan, Xu

    2015-03-01

    To understand the mechanism underlying autophagy in regulating dendritic cells during rat liver regeneration, we used the method of percoll density gradient centrifugation combined with immunomagnetic bead to isolate dendritic cells, the Rat Genome 230 2.0 Array to determine the expression changes of autophagy-related genes, and Ingenuity Pathway Analysis 9.0 (IPA) to determine the autophagy activities. The results indicated that LC3, BECN1, ATG7 and SQSTM1 genes had significant expression changes during rat liver regeneration. There were 593 genes related to autophagy, among which 210 genes were identified as significant. We also showed that the activity of autophagy was enhanced in the priming phase and teminal phase of liver regeneration, weakened in the proliferative stage by comparative analysis method of IPA. The autophagy-related physiological activities mainly included RNA expression, RNA transcription, cell differentiation and proliferation, involving in PPARα/RXRα activation, acute phase response signaling, TREM1 signaling, IL-6 signaling, IL-8 signaling and IL-1 signaling, whose activities were increased or decreased in liver regeneration. Cluster analysis found that P53 and AMPK signaling participated in the regulation of dendritic cells autophagy, with AMPK signaling in the priming phase of liver regeneration, and both signaling pathways in the terminal phase. We conclude that dendritic cells autophagy played an important role in initiation of the immune response in priming phase and depletion of dendritic cells in late phase during rat liver regeneration.

  8. Specific activin receptor-like kinase 3 inhibitors enhance liver regeneration.

    PubMed

    Tsugawa, Daisuke; Oya, Yuki; Masuzaki, Ryota; Ray, Kevin; Engers, Darren W; Dib, Martin; Do, Nhue; Kuramitsu, Kaori; Ho, Karen; Frist, Audrey; Yu, Paul B; Bloch, Kenneth D; Lindsley, Craig W; Hopkins, Corey R; Hong, Charles C; Karp, Seth J

    2014-12-01

    Pharmacologic agents to enhance liver regeneration after injury would have wide therapeutic application. Based on previous work suggesting inhibition of bone morphogenetic protein (BMP) signaling stimulates liver regeneration, we tested known and novel BMP inhibitors for their ability to accelerate regeneration in a partial hepatectomy (PH) model. Compounds were produced based on the 3,6-disubstituted pyrazolo[1,5-a] pyrimidine core of the BMP antagonist dorsomorphin and evaluated for their ability to inhibit BMP signaling and enhance liver regeneration. Antagonists of the BMP receptor activin receptor-like kinase 3 (ALK3), including LDN-193189 (LDN; 4-[6-[4-(1-piperazinyl)phenyl]pyrazolo[1,5-a]pyrimidin-3-yl]-quinoline), DMH2 (4-(2-(4-(3-(quinolin-4-yl)pyrazolo[1,5-a]pyrimidin-6-yl)phenoxy)ethyl)morpholine; VU0364849), and the novel compound VU0465350 (7-(4-isopropoxyphenyl)-3-(1H-pyrazol-4-yl)imidazo[1,2-a]pyridine; VU5350), blocked SMAD phosphorylation in vitro and in vivo, and enhanced liver regeneration after PH. In contrast, an antagonist of the BMP receptor ALK2, VU0469381 (5-(6-(4-methoxyphenyl)pyrazolo[1,5-a]pyrimidin-3-yl)quinolone; 1LWY), did not affect liver regeneration. LDN did not affect liver synthetic or metabolic function. Mechanistically, LDN increased serum interleukin-6 levels and signal transducer and activator of transcription 3 phosphorylation in the liver, and modulated other factors known to be important for liver regeneration, including suppressor of cytokine signaling 3 and p53. These findings suggest that inhibition of ALK3 may be part of a therapeutic strategy for treating human liver disease.

  9. Specific activin receptor-like kinase 3 inhibitors enhance liver regeneration.

    PubMed

    Tsugawa, Daisuke; Oya, Yuki; Masuzaki, Ryota; Ray, Kevin; Engers, Darren W; Dib, Martin; Do, Nhue; Kuramitsu, Kaori; Ho, Karen; Frist, Audrey; Yu, Paul B; Bloch, Kenneth D; Lindsley, Craig W; Hopkins, Corey R; Hong, Charles C; Karp, Seth J

    2014-12-01

    Pharmacologic agents to enhance liver regeneration after injury would have wide therapeutic application. Based on previous work suggesting inhibition of bone morphogenetic protein (BMP) signaling stimulates liver regeneration, we tested known and novel BMP inhibitors for their ability to accelerate regeneration in a partial hepatectomy (PH) model. Compounds were produced based on the 3,6-disubstituted pyrazolo[1,5-a] pyrimidine core of the BMP antagonist dorsomorphin and evaluated for their ability to inhibit BMP signaling and enhance liver regeneration. Antagonists of the BMP receptor activin receptor-like kinase 3 (ALK3), including LDN-193189 (LDN; 4-[6-[4-(1-piperazinyl)phenyl]pyrazolo[1,5-a]pyrimidin-3-yl]-quinoline), DMH2 (4-(2-(4-(3-(quinolin-4-yl)pyrazolo[1,5-a]pyrimidin-6-yl)phenoxy)ethyl)morpholine; VU0364849), and the novel compound VU0465350 (7-(4-isopropoxyphenyl)-3-(1H-pyrazol-4-yl)imidazo[1,2-a]pyridine; VU5350), blocked SMAD phosphorylation in vitro and in vivo, and enhanced liver regeneration after PH. In contrast, an antagonist of the BMP receptor ALK2, VU0469381 (5-(6-(4-methoxyphenyl)pyrazolo[1,5-a]pyrimidin-3-yl)quinolone; 1LWY), did not affect liver regeneration. LDN did not affect liver synthetic or metabolic function. Mechanistically, LDN increased serum interleukin-6 levels and signal transducer and activator of transcription 3 phosphorylation in the liver, and modulated other factors known to be important for liver regeneration, including suppressor of cytokine signaling 3 and p53. These findings suggest that inhibition of ALK3 may be part of a therapeutic strategy for treating human liver disease. PMID:25271257

  10. Fibroblast growth factor 15 deficiency impairs liver regeneration in mice.

    PubMed

    Kong, Bo; Huang, Jiansheng; Zhu, Yan; Li, Guodong; Williams, Jessica; Shen, Steven; Aleksunes, Lauren M; Richardson, Jason R; Apte, Udayan; Rudnick, David A; Guo, Grace L

    2014-05-15

    Fibroblast growth factor (FGF) 15 (human homolog, FGF19) is an endocrine FGF highly expressed in the small intestine of mice. Emerging evidence suggests that FGF15 is critical for regulating hepatic functions; however, the role of FGF15 in liver regeneration is unclear. This study assessed whether liver regeneration is altered in FGF15 knockout (KO) mice following 2/3 partial hepatectomy (PHx). The results showed that FGF15 KO mice had marked mortality, with the survival rate influenced by genetic background. Compared with wild-type mice, the KO mice displayed extensive liver necrosis and marked elevation of serum bile acids and bilirubin. Furthermore, hepatocyte proliferation was reduced in the KO mice because of impaired cell cycle progression. After PHx, the KO mice had weaker activation of signaling pathways that are important for liver regeneration, including signal transducer and activator of transcription 3, nuclear factor-κB, and mitogen-activated protein kinase. Examination of the KO mice at early time points after PHx revealed a reduced and/or delayed induction of immediate-early response genes, including growth-control transcription factors that are critical for liver regeneration. In conclusion, the results suggest that FGF15 deficiency severely impairs liver regeneration in mice after PHx. The underlying mechanism is likely the result of disrupted bile acid homeostasis and impaired priming of hepatocyte proliferation.

  11. Liver graft regeneration in right lobe adult living donor liver transplantation.

    PubMed

    Cheng, Y-F; Huang, T-L; Chen, T-Y; Tsang, L L-C; Ou, H-Y; Yu, C-Y; Concejero, A; Wang, C-C; Wang, S-H; Lin, T-S; Liu, Y-W; Yang, C-H; Yong, C-C; Chiu, K-W; Jawan, B; Eng, H-L; Chen, C-L

    2009-06-01

    Optimal portal flow is one of the essentials in adequate liver function, graft regeneration and outcome of the graft after right lobe adult living donor liver transplantation (ALDLT). The relations among factors that cause sufficient liver graft regeneration are still unclear. The aim of this study is to evaluate the potential predisposing factors that encourage liver graft regeneration after ALDLT. The study population consisted of right lobe ALDLT recipients from Chang Gung Memorial Hospital-Kaohsiung Medical Center, Taiwan. The records, preoperative images, postoperative Doppler ultrasound evaluation and computed tomography studies performed 6 months after transplant were reviewed. The volume of the graft 6 months after transplant divided by the standard liver volume was calculated as the regeneration ratio. The predisposing risk factors were compiled from statistical analyses and included age, recipient body weight, native liver disease, spleen size before transplant, patency of the hepatic venous graft, graft weight-to-recipient weight ratio (GRWR), posttransplant portal flow, vascular and biliary complications and rejection. One hundred forty-five recipients were enrolled in this study. The liver graft regeneration ratio was 91.2 +/- 12.6% (range, 58-151). The size of the spleen (p = 0.00015), total portal flow and GRWR (p = 0.005) were linearly correlated with the regeneration rate. Patency of the hepatic venous tributary reconstructed was positively correlated to graft regeneration and was statistically significant (p = 0.017). Splenic artery ligation was advantageous to promote liver regeneration in specific cases but splenectomy did not show any positive advantage. Spleen size is a major factor contributing to portal flow and may directly trigger regeneration after transplant. Control of sufficient portal flow and adequate hepatic outflow are important factors in graft regeneration.

  12. Different doses of partial liver irradiation promotes hepatic regeneration in rat.

    PubMed

    Liu, Ying; Shi, Changzheng; Cui, Meng; Yang, Zhenhua; Gan, Danhui; Wang, Yiming

    2015-01-01

    The aim of this study is to investigate whether partial liver irradiation promotes hepatic regeneration in rat. Left-half liver of rat was irradiated to 10 Gy, and the Right-half to 0, 5, 10 and 15 Gy, respectively. Then, serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) levels were evaluated on 0 day, 15-day, 30-day, 45-day and 60-day after liver irradiation. Next, the serum HGF, NF-κB and TGF-β1 levels were also analyzed on 60-day after liver irradiation. Lastly, the cyclinD1 protein expression was appraised by western blots on 60-day after liver irradiation. ALT, AST and ALP levels were reduced compared with that of controls. The serum HGF, NF-κB and TGF-β1 levels, and the cyclinD1 protein expression in liver irradiation group were increased compared with that of controls group. However, hepatic regeneration of higher dose-irradiated cirrhotic liver was triggered a more enhanced regeneration, compared with that of higher doses group. In summary, these results suggest that different doses of partial liver irradiation promotes hepatic regeneration in rat.

  13. Signals and Cells Involved in Regulating Liver Regeneration

    PubMed Central

    Kang, Liang-I.; Mars, Wendy M.; Michalopoulos, George K.

    2012-01-01

    Liver regeneration is a complex phenomenon aimed at maintaining a constant liver mass in the event of injury resulting in loss of hepatic parenchyma. Partial hepatectomy is followed by a series of events involving multiple signaling pathways controlled by mitogenic growth factors (HGF, EGF) and their receptors (MET and EGFR). In addition multiple cytokines and other signaling molecules contribute to the orchestration of a signal which drives hepatocytes into DNA synthesis. The other cell types of the liver receive and transmit to hepatocytes complex signals so that, in the end of the regenerative process, complete hepatic tissue is assembled and regeneration is terminated at the proper time and at the right liver size. If hepatocytes fail to participate in this process, the biliary compartment is mobilized to generate populations of progenitor cells which transdifferentiate into hepatocytes and restore liver size. PMID:24710554

  14. Rat liver regeneration following ablation with irreversible electroporation

    PubMed Central

    Bruinsma, Bote G.; Jaramillo, Maria; Yarmush, Martin L.

    2016-01-01

    During the past decade, irreversible electroporation (IRE) ablation has emerged as a promising tool for the treatment of multiple diseases including hepatic cancer. However, the mechanisms behind the tissue regeneration following IRE ablation have not been investigated. Our results indicate that IRE treatment immediately kills the cells at the treatment site preserving the extracellular architecture, in effect causing in vivo decellularization. Over the course of 4 weeks, progenitor cell differentiation, through YAP and notch pathways, together with hepatocyte expansion led to almost complete regeneration of the ablated liver leading to the formation of hepatocyte like cells at the ablated zone. We did not observe significant scarring or tumor formation at the regenerated areas 6 months post IRE. Our study suggests a new model to study the regeneration of liver when the naïve extracellular matrix is decellularized in vivo with completely preserved extracellular architecture. PMID:26819842

  15. Partial Hepatectomy Induced Long Noncoding RNA Inhibits Hepatocyte Proliferation during Liver Regeneration

    PubMed Central

    Huang, Lulu; Damle, Sagar S.; Booten, Sheri; Singh, Priyam; Sabripour, Mahyar; Hsu, Jeff; Jo, Minji; Katz, Melanie; Watt, Andy; Hart, Christopher E.; Freier, Susan M.; Monia, Brett P.; Guo, Shuling

    2015-01-01

    Liver regeneration after partial hepatectomy (PHx) is a complex and well-orchestrated biological process in which synchronized cell proliferation is induced in response to the loss of liver mass. To define long noncoding RNAs (lncRNAs) that participate in the regulation of liver regeneration, we performed microarray analysis and identified more than 400 lncRNAs exhibiting significantly altered expression. Of these, one lncRNA, LncPHx2 (Long noncoding RNA induced by PHx 2), was highly upregulated during liver regeneration. Depletion of LncPHx2 during liver regeneration using antisense oligonucleotides led to a transient increase in hepatocyte proliferation and more rapid liver regeneration. Gene expression analysis showed that LncPHx2 depletion resulted in upregulation of mRNAs encoding proteins known to promote cell proliferation, including MCM components, DNA polymerases, histone proteins, and transcription factors. LncPHx2 interacts with the mRNAs of MCM components, making it a candidate to regulate the expression of MCMs and other genes post-transcriptionally. Collectively, our data demonstrate that LncPHx2 is a key lncRNA that participates in a negative feedback loop modulating hepatocyte proliferation through RNA-RNA interactions. PMID:26207833

  16. Loss of α-catenin elicits a cholestatic response and impairs liver regeneration

    PubMed Central

    Herr, Keira Joann; Tsang, Ying-hung Nicole; Ong, Joanne Wei En; Li, Qiushi; Yap, Lai Lai; Yu, Weimiao; Yin, Hao; Bogorad, Roman L.; Dahlman, James E.; Chan, Yee Gek; Bay, Boon Huat; Singaraja, Roshni; Anderson, Daniel G.; Koteliansky, Victor; Viasnoff, Virgile; Thiery, Jean Paul

    2014-01-01

    The liver is unique in its capacity to regenerate after injury, during which hepatocytes actively divide and establish cell-cell contacts through cell adhesion complexes. Here, we demonstrate that the loss of α-catenin, a well-established adhesion component, dramatically disrupts liver regeneration. Using a partial hepatectomy model, we show that regenerated livers from α-catenin knockdown mice are grossly larger than control regenerated livers, with an increase in cell size and proliferation. This increased proliferation correlated with increased YAP activation, implicating α-catenin in the Hippo/YAP pathway. Additionally, α-catenin knockdown mice exhibited a phenotype reminiscent of clinical cholestasis, with drastically altered bile canaliculi, elevated levels of bile components and signs of jaundice and inflammation. The disrupted regenerative capacity is a result of actin cytoskeletal disorganisation, leading to a loss of apical microvilli, dilated lumens in the bile canaliculi, and leaky tight junctions. This study illuminates a novel, essential role for α-catenin in liver regeneration. PMID:25355493

  17. Expression patterns and action analysis of genes associated with inflammatory responses during rat liver regeneration

    PubMed Central

    Shao, Heng-Yi; Zhao, Li-Feng; Xu, Cun-Shuan

    2007-01-01

    AIM: To study the relationship between inflammatory response and liver regeneration (LR) at transcriptional level. METHODS: After partial hepatectomy (PH) of rats, the genes associated with inflammatory response were obtained according to the databases, and the gene expression changes during LR were checked by the Rat Genome 230 2.0 array. RESULTS: Two hundred and thirty-nine genes were associated with liver regeneration. The initial and total expressing gene numbers found in initiation phase (0.5-4 h after PH), G0/G1 transition (4-6 h after PH), cell proliferation (6-66 h after PH), cell differentiation and structure-function reconstruction (66-168 h after PH) of liver regeneration were 107, 34, 126, 6 and 107, 92, 233, 145 respectively, showing that the associated genes were mainly triggered at the beginning of liver regeneration, and worked at different phases. According to their expression similarity, these genes were classified into 5 groups: only up-regulated, predominantly up-, only down-, predominantly down-, up- and down-, involving 92, 25, 77, 14 and 31 genes, respectively. The total times of their up- and down-regulated expression were 975 and 494, respectively, demonstrating that the expressions of the majority of genes were increased, and that of a few genes were decreased. Their time relevance was classified into 13 groups, showing that the cellular physiological and biochemical activities were staggered during liver regeneration. According to gene expression patterns, they were classified into 33 types, suggesting that the activities were diverse and complex during liver regeneration. CONCLUSION: Inflammatory response is closely associated with liver regeneration, in which 239 LR-associated genes play an important role. PMID:17230604

  18. Hepatic stellate cells contribute to progenitor cells and liver regeneration.

    PubMed

    Kordes, Claus; Sawitza, Iris; Götze, Silke; Herebian, Diran; Häussinger, Dieter

    2014-12-01

    Retinoid-storing hepatic stellate cells (HSCs) have recently been described as a liver-resident mesenchymal stem cell (MSC) population; however, it is not clear whether these cells contribute to liver regeneration or serve as a progenitor cell population with hepatobiliary characteristics. Here, we purified HSCs with retinoid-dependent fluorescence-activated cell sorting from eGFP-expressing rats and transplanted these GFP(+) HSCs into wild-type (WT) rats that had undergone partial hepatectomy in the presence of 2-acetylaminofluorene (2AAF) or retrorsine, both of which are injury models that favor stem cell-based liver repair. Transplanted HSCs contributed to liver regeneration in host animals by forming mesenchymal tissue, progenitor cells, hepatocytes, and cholangiocytes and elevated direct bilirubin levels in blood sera of GUNN rats, indicating recovery from the hepatic bilirubin-handling defect in these animals. Transplanted HSCs engrafted within the bone marrow (BM) of host animals, and HSC-derived cells were isolated from BM and successfully retransplanted into new hosts with injured liver. Cultured HSCs transiently adopted an expression profile similar to that of progenitor cells during differentiation into bile acid-synthesizing and -transporting hepatocytes, suggesting that stellate cells represent a source of liver progenitor cells. This concept connects seemingly contradictory studies that favor either progenitor cells or MSCs as important players in stem cell-based liver regeneration.

  19. Hepatic stellate cells contribute to progenitor cells and liver regeneration

    PubMed Central

    Kordes, Claus; Sawitza, Iris; Götze, Silke; Herebian, Diran; Häussinger, Dieter

    2014-01-01

    Retinoid-storing hepatic stellate cells (HSCs) have recently been described as a liver-resident mesenchymal stem cell (MSC) population; however, it is not clear whether these cells contribute to liver regeneration or serve as a progenitor cell population with hepatobiliary characteristics. Here, we purified HSCs with retinoid-dependent fluorescence-activated cell sorting from eGFP-expressing rats and transplanted these GFP+ HSCs into wild-type (WT) rats that had undergone partial hepatectomy in the presence of 2-acetylaminofluorene (2AAF) or retrorsine, both of which are injury models that favor stem cell–based liver repair. Transplanted HSCs contributed to liver regeneration in host animals by forming mesenchymal tissue, progenitor cells, hepatocytes, and cholangiocytes and elevated direct bilirubin levels in blood sera of GUNN rats, indicating recovery from the hepatic bilirubin–handling defect in these animals. Transplanted HSCs engrafted within the bone marrow (BM) of host animals, and HSC-derived cells were isolated from BM and successfully retransplanted into new hosts with injured liver. Cultured HSCs transiently adopted an expression profile similar to that of progenitor cells during differentiation into bile acid–synthesizing and –transporting hepatocytes, suggesting that stellate cells represent a source of liver progenitor cells. This concept connects seemingly contradictory studies that favor either progenitor cells or MSCs as important players in stem cell–based liver regeneration. PMID:25401473

  20. Native fluorescence characteristics of blood plasma during rat liver regeneration

    NASA Astrophysics Data System (ADS)

    Ganesan, Singaravelu; Madhuri, S.; Anuradha, V.; Namasivayam, A.; Parmeswearan, Diagaradjane

    1999-05-01

    Native fluorescence characteristics of blood plasma was studied in the visible region, during the regenerating phase of the rat liver tissue. Animals were subjected to partial hepatectomy (PH). Blood samples were collected after several intervals of post PH time and also from control animals. Native fluorescence spectra of blood plasma were measured at 405 nm excitation. In addition to the primary emission peak around 440 nm, the fluorescence spectra of experimental group of animals showed distinct secondary emission peak around 620 nm, which is found to be absent in the case of control animals. This may be attributed to the presence of endogenous porphyrins. The fluorescence intensity at 620 nm was found to be maximum at about 16 hrs of post PH time and it decreased thereafter with increasing post PH time. The spectral differences between controls and experimental animals were found to be minimal at 240 hrs of post PH time.

  1. Hepatocyte-specific ablation in zebrafish to study biliary-driven liver regeneration.

    PubMed

    Choi, Tae-Young; Khaliq, Mehwish; Ko, Sungjin; So, Juhoon; Shin, Donghun

    2015-05-20

    The liver has a great capacity to regenerate. Hepatocytes, the parenchymal cells of the liver, can regenerate in one of two ways: hepatocyte- or biliary-driven liver regeneration. In hepatocyte-driven liver regeneration, regenerating hepatocytes are derived from preexisting hepatocytes, whereas, in biliary-driven regeneration, regenerating hepatocytes are derived from biliary epithelial cells (BECs). For hepatocyte-driven liver regeneration, there are excellent rodent models that have significantly contributed to the current understanding of liver regeneration. However, no such rodent model exists for biliary-driven liver regeneration. We recently reported on a zebrafish liver injury model in which BECs extensively give rise to hepatocytes upon severe hepatocyte loss. In this model, hepatocytes are specifically ablated by a pharmacogenetic means. Here we present in detail the methods to ablate hepatocytes and to analyze the BEC-driven liver regeneration process. This hepatocyte-specific ablation model can be further used to discover the underlying molecular and cellular mechanisms of biliary-driven liver regeneration. Moreover, these methods can be applied to chemical screens to identify small molecules that augment or suppress liver regeneration.

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

    PubMed Central

    Jepsen, Betina Norman; Andersen, Kasper Jarlhelt; Knudsen, Anders Riegels; Nyengaard, Jens Randel; Hamilton-Dutoit, Stephen; Svendsen, Pia; Etzerodt, Anders; Møller, Holger Jon; Moestrup, Søren Kragh; Graversen, Jonas Heilskov; Mortensen, Frank Viborg

    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 with placebo, low dose dexamethasone, high dose dexamethasone or low dose anti-CD163 dexamethasone. Subsequently, the rats underwent 70% partial hepatectomy. The two sets were evaluated on postoperative day 2 or 5, respectively. Blood was drawn for circulating markers of inflammation and liver cell damage; liver tissue was sampled for analysis of regeneration rate and proliferation index. Results The high dose dexamethasone group had significantly lower body and liver weight than the placebo and anti-CD163-dex groups. There were no differences in liver regeneration rates between groups. Hepatocyte proliferation was completed faster in the placebo group, although this was not significant. The anti-CD163-dex group showed increased blood levels of albumin and alanine aminotransferase and a diminished inflammatory response in terms of significantly reduced haptoglobin, α2-macroglobulin and Interleukine-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. PMID:26779334

  3. Nrf2 is essential for timely M phase entry of replicating hepatocytes during liver regeneration.

    PubMed

    Zou, Yuhong; Hu, Min; Lee, Joonyong; Nambiar, Shashank Manohar; Garcia, Veronica; Bao, Qi; Chan, Jefferson Y; Dai, Guoli

    2015-02-15

    The transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) regulates various cellular activities, including redox balance, detoxification, metabolism, autophagy, proliferation, and apoptosis. Several studies have demonstrated that Nrf2 regulates hepatocyte proliferation during liver regeneration. The aim of this study was to investigate how Nrf2 modulates the cell cycle of replicating hepatocytes in regenerating livers. Wild-type and Nrf2 null mice were subjected to 2/3 partial hepatectomy (PH) and killed at multiple time points for various analyses. Nrf2 null mice exhibited delayed liver regrowth, although the lost liver mass was eventually restored 7 days after PH. Nrf2 deficiency did not affect the number of hepatocytes entering the cell cycle but did delay hepatocyte mitosis. Mechanistically, the lack of Nrf2 resulted in increased mRNA and protein levels of hepatic cyclin A2 when the remaining hepatocytes were replicating in response to PH. Moreover, Nrf2 deficiency in regenerating livers caused dysregulation of Wee1, Cdc2, and cyclin B1 mRNA and protein expression, leading to decreased Cdc2 activity. Thus, Nrf2 is required for timely M phase entry of replicating hepatocytes by ensuring proper regulation of cyclin A2 and the Wee1/Cdc2/cyclin B1 pathway during liver regeneration.

  4. Bile acids are "homeotrophic" sensors of the functional hepatic capacity and regulate adaptive growth during liver regeneration.

    PubMed

    Geier, Andreas; Trautwein, Christian

    2007-01-01

    Liver mass depends on one or more unidentified humoral signals that drive regeneration when liver functional capacity is diminished. Bile acids are important liver products, and their levels are tightly regulated. Here, we identify a role for nuclear receptor-dependent bile acid signaling in normal liver regeneration. Elevated bile acid levels accelerate regeneration, and decreased levels inhibit liver regrowth, as does the absence of the primary nuclear bile acid receptor FXR. We propose that FXR activation by increased bile acid flux is a signal of decreased functional capacity of the liver. FXR, and possibly other nuclear receptors, may promote homeostasis not only by regulating expression of appropriate metabolic target genes but also by driving homeotrophic liver growth.

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

    PubMed

    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.

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

    PubMed

    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. PMID:18794562

  7. Mechanistic insights of rapid liver regeneration after associating liver partition and portal vein ligation for stage hepatectomy

    PubMed Central

    Moris, Demetrios; Vernadakis, Spyridon; Papalampros, Alexandros; Vailas, Michail; Dimitrokallis, Nikolaos; Petrou, Athanasios; Dimitroulis, Dimitrios

    2016-01-01

    AIM To highlight the potential mechanisms of regeneration in the Associating Liver Partition and Portal vein ligation for Stage hepatectomy models (clinical and experimental) that could unlock the myth behind the extraordinary capability of the liver for regeneration, which would help in designing new therapeutic options for the regenerative drive in difficult setup, such as chronic liver diseases. Associating Liver Partition and Portal vein ligation for Stage hepatectomy has been recently advocated to induce rapid future liver remnant hypertrophy that significantly shortens the time for the second stage hepatectomy. The introduction of Associating Liver Partition and Portal vein ligation for Stage hepatectomy in the surgical armamentarium of therapeutic tools for liver surgeons represented a real breakthrough in the history of liver surgery. METHODS A comprehensive literature review of Associating Liver Partition and Portal vein ligation for Stage hepatectomy and its utility in liver regeneration is performed. RESULTS Liver regeneration after Associating Liver Partition and Portal vein ligation for Stage hepatectomy is a combination of portal flow changes and parenchymal transection that generate a systematic response inducing hepatocyte proliferation and remodeling. CONCLUSION Associating Liver Partition and Portal vein ligation for Stage hepatectomy represents a real breakthrough in the history of liver surgery because it offers rapid liver regeneration potential that facilitate resection of liver tumors that were previously though unresectable. The jury is still out though in terms of safety, efficacy and oncological outcomes. As far as Associating Liver Partition and Portal vein ligation for Stage hepatectomy -induced liver regeneration is concerned, further research on the field should focus on the role of non-parenchymal cells in liver regeneration as well as on the effect of Associating Liver Partition and Portal vein ligation for Stage hepatectomy in liver

  8. Impaired liver function attenuates liver regeneration and hypertrophy after portal vein embolization

    PubMed Central

    Kageyama, Yumiko; Kokudo, Takashi; Amikura, Katsumi; Miyazaki, Yoshihiro; Takahashi, Amane; Sakamoto, Hirohiko

    2016-01-01

    AIM To clarify the clinical factors associated with liver regeneration after major hepatectomy and the hypertrophic rate after portal vein embolization (PVE). METHODS A total of 63 patients who underwent major hepatectomy and 13 patients who underwent PVE in a tertiary care hospital between January 2012 and August 2015 were included in the analysis. We calculated the remnant liver volume following hepatectomy using contrast-enhanced computed tomography (CT) performed before and approximately 3-6 mo after hepatectomy. Furthermore, we calculated the liver volume using CT performed 2-4 wk after PVE. Preoperative patient characteristics and laboratory data were analyzed to identify factors affecting postoperative liver regeneration or hypertrophy rate following PVE. RESULTS The remnant liver volume/total liver volume ratio negatively correlated with the liver regeneration rate after hepatectomy (ρ = -0.850, P < 0.001). The regeneration rate was significantly lower in patients with an indocyanine green retention rate at 15 min (ICG-R15) of ≥ 20% in the right hepatectomy group but not in the left hepatectomy group. The hypertrophic rate after PVE positively correlated with the regeneration rate after hepatectomy (ρ = 0.648, P = 0.017). In addition, the hypertrophic rate after PVE was significantly lower in patients with an ICG-R15 ≥ 20% and a serum total bilirubin ≥ 1.5 mg/dL. CONCLUSION The regeneration rate after major hepatectomy correlated with hypertrophic rate after PVE. Both of them were attenuated in the presence of impaired liver function. PMID:27729956

  9. Intermittent selective clamping improves rat liver regeneration by attenuating oxidative and endoplasmic reticulum stress.

    PubMed

    Ben Mosbah, I; Duval, H; Mbatchi, S-F; Ribault, C; Grandadam, S; Pajaud, J; Morel, F; Boudjema, K; Compagnon, P; Corlu, A

    2014-03-06

    Intermittent clamping of the portal trial is an effective method to avoid excessive blood loss during hepatic resection, but this procedure may cause ischemic damage to liver. Intermittent selective clamping of the lobes to be resected may represent a good alternative as it exposes the remnant liver only to the reperfusion stress. We compared the effect of intermittent total or selective clamping on hepatocellular injury and liver regeneration. Entire hepatic lobes or only lobes to be resected were subjected twice to 10 min of ischemia followed by 5 min of reperfusion before hepatectomy. We provided evidence that the effect of intermittent clamping can be damaging or beneficial depending to its mode of application. Although transaminase levels were similar in all groups, intermittent total clamping impaired liver regeneration and increased apoptosis. In contrast, intermittent selective clamping improved liver protein secretion and hepatocyte proliferation when compared with standard hepatectomy. This beneficial effect was linked to better adenosine-5'-triphosphate (ATP) recovery, nitric oxide production, antioxidant activities and endoplasmic reticulum adaptation leading to limit mitochondrial damage and apoptosis. Interestingly, transient and early chaperone inductions resulted in a controlled activation of the unfolded protein response concomitantly to endothelial nitric oxide synthase, extracellular signal-regulated kinase-1/2 (ERK1/2) and p38 MAPK activation that favors liver regeneration. Endoplasmic reticulum stress is a central target through which intermittent selective clamping exerts its cytoprotective effect and improves liver regeneration. This procedure could be applied as a powerful protective modality in the field of living donor liver transplantation and liver surgery.

  10. Intermittent selective clamping improves rat liver regeneration by attenuating oxidative and endoplasmic reticulum stress.

    PubMed

    Ben Mosbah, I; Duval, H; Mbatchi, S-F; Ribault, C; Grandadam, S; Pajaud, J; Morel, F; Boudjema, K; Compagnon, P; Corlu, A

    2014-01-01

    Intermittent clamping of the portal trial is an effective method to avoid excessive blood loss during hepatic resection, but this procedure may cause ischemic damage to liver. Intermittent selective clamping of the lobes to be resected may represent a good alternative as it exposes the remnant liver only to the reperfusion stress. We compared the effect of intermittent total or selective clamping on hepatocellular injury and liver regeneration. Entire hepatic lobes or only lobes to be resected were subjected twice to 10 min of ischemia followed by 5 min of reperfusion before hepatectomy. We provided evidence that the effect of intermittent clamping can be damaging or beneficial depending to its mode of application. Although transaminase levels were similar in all groups, intermittent total clamping impaired liver regeneration and increased apoptosis. In contrast, intermittent selective clamping improved liver protein secretion and hepatocyte proliferation when compared with standard hepatectomy. This beneficial effect was linked to better adenosine-5'-triphosphate (ATP) recovery, nitric oxide production, antioxidant activities and endoplasmic reticulum adaptation leading to limit mitochondrial damage and apoptosis. Interestingly, transient and early chaperone inductions resulted in a controlled activation of the unfolded protein response concomitantly to endothelial nitric oxide synthase, extracellular signal-regulated kinase-1/2 (ERK1/2) and p38 MAPK activation that favors liver regeneration. Endoplasmic reticulum stress is a central target through which intermittent selective clamping exerts its cytoprotective effect and improves liver regeneration. This procedure could be applied as a powerful protective modality in the field of living donor liver transplantation and liver surgery. PMID:24603335

  11. Dynamic alterations in Hippo signaling pathway and YAP activation during liver regeneration.

    PubMed

    Grijalva, James L; Huizenga, Megan; Mueller, Kaly; Rodriguez, Steven; Brazzo, Joseph; Camargo, Fernando; Sadri-Vakili, Ghazaleh; Vakili, Khashayar

    2014-07-15

    The Hippo signaling pathway has been implicated in mammalian organ size regulation and tumor suppression. Specifically, the Hippo pathway plays a critical role regulating the activity of transcriptional coactivator Yes-associated protein (YAP), which modulates a proliferative transcriptional program. Recent investigations have demonstrated that while this pathway is activated in quiescent livers, its inhibition leads to liver overgrowth and tumorigenesis. However, the role of the Hippo pathway during the natural process of liver regeneration remains unknown. Here we investigated alterations in the Hippo signaling pathway and YAP activation during liver regeneration using a 70% partial hepatectomy (PH) rat model. Our results indicate an increase in YAP activation by 1 day following PH as demonstrated by increased YAP nuclear localization and increased YAP target gene expression. Investigation of the Hippo pathway revealed a decrease in the activation of core kinases Mst1/2 by 1 day as well as Lats1/2 and its adapter protein Mob1 by 3 days following PH. Evaluation of liver-to-body weight ratios indicated that the liver reaches its near normal size by 7 days following PH, which correlated with a return to baseline YAP nuclear levels and target gene expression. Additionally, when liver size was restored, Mst1/2 kinase activation returned to levels observed in quiescent livers indicating reactivation of the Hippo signaling pathway. These findings illustrate the dynamic changes in the Hippo signaling pathway and YAP activation during liver regeneration, which stabilize when the liver-to-body weight ratio reaches homeostatic levels.

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

    PubMed

    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. PMID:21264506

  13. Loss of Survivin influences liver regeneration and is associated with impaired Aurora B function

    PubMed Central

    Hagemann, S; Wohlschlaeger, J; Bertram, S; Levkau, B; Musacchio, A; Conway, E M; Moellmann, D; Kneiseler, G; Pless-Petig, G; Lorenz, K; Sitek, B; Baba, H A

    2013-01-01

    The chromosomal passenger complex (CPC) acts as a key regulator of mitosis, preventing asymmetric segregation of chromosomal material into daughter cells. The CPC is composed of three non-enzymatic components termed Survivin, the inner centromere protein (INCENP) and Borealin, and an enzymatic component, Aurora B kinase. Survivin is necessary for the appropriate separation of sister chromatids during mitosis and is involved in liver regeneration, but its role in regenerative processes is incompletely elucidated. Whether Survivin, which is classified as an inhibitor of apoptosis protein (IAP) based on domain composition, also has a role in apoptosis is controversial. The present study examined the in vivo effects of Survivin ablation in the liver and during liver regeneration after 70% hepatectomy in a hepatocyte-specific knockout mouse model. The absence of Survivin caused a reduction in the number of hepatocytes in the liver, together with an increase in cell volume, macronucleation and polyploidy, but no changes in apoptosis. During liver regeneration, mitosis of hepatocytes was associated with mislocalization of the members of the CPC, which were no longer detectable at the centromere despite an unchanged protein amount. Furthermore, the loss of survivin in regenerating hepatocytes was associated with reduced levels of phosphorylated Histone H3 at serine 28 and abolished phosphorylation of CENP-A and Hec1 at serine 55, which is a consequence of decreased Aurora B kinase activity. These data indicate that Survivin expression determines hepatocyte number during liver development and liver regeneration. Lack of Survivin causes mislocalization of the CPC members in combination with reduced Aurora B activity, leading to impaired phosphorylation of its centromeric target proteins and inappropriate cytokinesis. PMID:23519077

  14. Oral administration of polyamines ameliorates liver ischemia/reperfusion injury and promotes liver regeneration in rats.

    PubMed

    Okumura, Shinya; Teratani, Takumi; Fujimoto, Yasuhiro; Zhao, Xiangdong; Tsuruyama, Tatsuaki; Masano, Yuki; Kasahara, Naoya; Iida, Taku; Yagi, Shintaro; Uemura, Tadahiro; Kaido, Toshimi; Uemoto, Shinji

    2016-09-01

    Polyamines are essential for cell growth and differentiation. They play important roles in protection from liver damage and promotion of liver regeneration. However, little is known about the effect of oral exogenous polyamine administration on liver damage and regeneration. This study investigated the impact of polyamines (spermidine and spermine) on ischemia/reperfusion injury (IRI) and liver regeneration. We used a rat model in which a 70% hepatectomy after 40 minutes of ischemia was performed to mimic the clinical condition of living donor partial liver transplantation (LT). Male Lewis rats were separated into 2 groups: a polyamine group given polyamines before and after operation as treatment and a vehicle group given distilled water as placebo. The levels of serum aspartate aminotransferase and alanine aminotransferase at 6, 24, and 48 hours after reperfusion were significantly lower in the polyamine group compared with those in the vehicle group. Polyamine treatment reduced the expression of several proinflammatory cytokines and chemokines at 6 hours after reperfusion. Histological analysis showed significantly less necrosis and apoptosis in the polyamine group at 6 hours after reperfusion. Sinusoidal endothelial cells were also well preserved in the polyamine group. In addition, the regeneration of the remnant liver at 24, 48, and 168 hours after reperfusion was significantly accelerated, and the Ki-67 labeling index and the expressions of proliferating cell nuclear antigen and phosphorylated retinoblastoma protein at 24 hours after reperfusion were significantly higher in the polyamine group compared with those in the vehicle group. In conclusion, perioperative oral polyamine administration attenuates liver IRI and promotes liver regeneration. It might be a new therapeutic option to improve the outcomes of partial LT. Liver Transplantation 22 1231-1244 2016 AASLD. PMID:27102080

  15. Local delivery of vascular endothelial growth factor via nanofiber matrix improves liver regeneration after extensive hepatectomy in rats.

    PubMed

    Yu, Yuan-Quan; Jiang, Xue-Song; Gao, Song; Ma, Rui; Jin, Yun; Jin, Xing; Peng, Shu-You; Mao, Hai-Quan; Li, Jiang-Tao

    2014-11-01

    Vascular endothelial growth factor (VEGF) is a potent regulator for liver regeneration following partial hepatectomy. However, intravenous delivery of VEGF has yielded limited success in promoting the regeneration of remnant liver. Here we report a new approach to locally deliver recombinant VEGF from an electrospun poly-ε-caprolactone nanofiber mesh and its effect on improving rat liver regeneration after 70% hepatectomy. After applying the VEGF-releasing nanofiber mesh to the remnant liver lobes following hepatectomy in rats, the fractions of proliferating hepatocytes increased markedly at 48 h and 72 h in comparison with the control group receiving nanofiber meshes without VEGF. The expression of endogenous VEGF in liver tissue was also higher in the VEGF-nanofiber group than those in the control group. These results demonstrate that biodegradable nanofiber meshes offer a convenient and effective approach for local and sustained delivery of VEGF to the remnant liver following partial hepatectomy.

  16. Phycocyanobilin accelerates liver regeneration and reduces mortality rate in carbon tetrachloride-induced liver injury mice

    PubMed Central

    Liu, Jie; Zhang, Qing-Yu; Yu, Li-Ming; Liu, Bin; Li, Ming-Yi; Zhu, Run-Zhi

    2015-01-01

    AIM: To investigate the hepatoprotective effects of phycocyanobilin (PCB) in reducing hepatic injury and accelerating hepatocyte proliferation following carbon tetrachloride (CCl4) treatment. METHODS: C57BL/6 mice were orally administered PCB 100 mg/kg for 4 d after CCl4 injection, and then the serum and liver tissue of the mice were collected at days 1, 2, 3, 5 and 7 after CCl4 treatment. A series of evaluations were performed to identify the curative effects on liver injury and recovery. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), albumin and superoxide dismutase (SOD) were detected to indirectly assess the anti-inflammatory effects of PCB. Meanwhile, we detected the expressions of hepatocyte growth factor, transforming growth factor alpha (TGF-α), TGF-β, tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6), the factors which are associated with inflammation and liver regeneration. The protein expressions of proliferating cell nuclear antigen (PCNA), TNF-α and cytochrome C were detected by western blot. Furthermore, the survival rates were analyzed of mice which were administered a lethal dose of CCl4 (2.6 mg/kg) with or without PCB. RESULTS: In our research, PCB showed a strongly anti-inflammatory effect on CCl4-induced liver injury in mice. The ALT was significantly decreased after CCl4 treatment from day 1 (P < 0.01) and the AST was significantly decreased from day 2 (P < 0.001). Both albumin and liver SOD were increased from day 2 (P < 0.001 and P < 0.01), but serum SOD levels did not show a significant increase (P > 0.05). PCB protected the structure of liver from the injury by CCl4. TUNEL assay showed that PCB dramatically reduced the number of apoptotic cells after CCl4 treatment compared to the control (101.0 ± 25.4 vs 25.7 ± 6.4, P < 0.01). The result of western blotting showed that PCB could increase PCNA expression, decrease TNF-α and cytochrome C expression. Furthermore, data shows that PCB could improve the

  17. [Control of growth and expression of protooncogenes in regenerating liver].

    PubMed

    Zou, Y; Gong, D Z; Cui, X Y; Mei, M H

    1996-01-01

    There are many humoral factors involved in the control of growth in regenerating liver. The complete hepatocyte mitogens such as hepatocyte growth factor (HGF), hepatic stimulator substance (HSS) can strongly stimulate hepatocyte DNA synthesis and mitosis. The hepatocyte growth inhibitors such as transforming growth factor beta 1 (TGF beta 1), however, do not stimulate DNA synthesis, but inhibit EGF mitogenesis. In addition, the comitogens such as norepinephrine and insulin are necessary to regulate the growth of regenerating liver. It has become clear that the hepatocyte proliferation and protooncogenes are linked closely. Some protooncogenes can express specifically as markers in the different phases of the cell cycle and in hepatocytes that enter the cell cycle (G0 to G1 transit) and continue to progress.

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

    PubMed Central

    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

    ABSTRACT Background: 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. Aim: Evaluate the effects of tranexamic acid on liver regeneration after partial hepatectomy in rats. Method: 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. Results: 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. Conclusion: Tranexamic acid was effective in liver regeneration, but in longer period after partial hepatectomy. PMID:27438036

  19. Acute ethanol preexposure promotes liver regeneration after partial hepatectomy in mice by activating ALDH2.

    PubMed

    Ding, Xiang; Beier, Juliane I; Baldauf, Keegan J; Jokinen, Jenny D; Zhong, Hai; Arteel, Gavin E

    2014-01-01

    It is known that chronic ethanol significantly impairs liver regeneration. However, the effect of acute ethanol exposure on liver regeneration remains largely unknown. To address this question, C57Bl6/J mice were exposed to acute ethanol (6 g/kg intragastrically) for 3 days, and partial hepatectomy (PHx) was performed 24 h after the last dose. Surprisingly, acute ethanol preexposure promoted liver regeneration. This effect of ethanol did not correlate with changes in expression of cell cycle regulatory genes (e.g., cyclin D1, p21, and p27) but did correlate with protection against the effect of PHx on indices of impaired lipid and carbohydrate metabolism. Ethanol preexposure protected against inhibition of the oxidant-sensitive mitochondrial enzyme, aconitase. The activity of aldehyde dehydrogenase 2 (ALDH2) was significantly increased by ethanol preexposure. The effect of ethanol was blocked by inhibiting (Daidzin) and was mimicked by activating (Alda-1) ALDH2. Lipid peroxides are also substrates for ALDH2; indeed, alcohol preexposure blunted the increase in lipid peroxidation (4OH-nonenal adducts) caused by PHx. Taken together, these data suggest that acute preoperative ethanol exposure "preconditions" the liver to respond more rapidly to regenerate after PHx by activating mitochondrial ALDH2, which prevents oxidative stress in this compartment.

  20. Expression patterns and action analysis of genes associated with drug-induced liver diseases during rat liver regeneration

    PubMed Central

    Ning, Qian-Ji; Qin, Shao-Wei; Xu, Cun-Shuan

    2006-01-01

    AIM: To study the action of the genes associated with drug-induced liver diseases at the gene transcriptional level during liver regeneration (LR) in rats. METHODS: The genes associated with drug-induced liver diseases were obtained by collecting the data from databases and literature, and the gene expression changes in the regenerating liver were checked by the Rat Genome 230 2.0 array. RESULTS: The initial and total expression numbers of genes occurring in phases of 0.5-4 h after partial hepatectomy (PH), 4-6 h after PH (G0/G1 transition), 6-66 h after PH (cell proliferation), 66-168 h after PH (cell differentiation and structure-function reconstruction) were 21, 3, 9, 2 and 21, 9, 19, 18, respectively. It is illustrated that the associated genes were mainly triggered at the initial stage of LR and worked at different phases. According to their expression similarity, these genes were classified into 5 types: only up-regulated (12 genes), predominantly up-regulated (4 genes), only down-regulated (11 genes), predominantly down-regulated (3 genes), and approximately up-/down-regulated (2 genes). The total times of their up- and down-expression were 130 and 79, respectively, demonstrating that expression of most of the genes was increased during LR, while a few decreased. The cell physiological and biochemical activities during LR were staggered according to the time relevance and were diverse and complicated in gene expression patterns. CONCLUSION: Drug metabolic capacity in regenerating liver was enhanced. Thirty-two genes play important roles during liver regeneration in rats. PMID:17109518

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

    SciTech Connect

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

    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.

  2. The Involving Roles of Intrahepatic and Extrahepatic Stem/Progenitor Cells (SPCs) to Liver Regeneration.

    PubMed

    Liu, Wei-Hui; Ren, Li-Na; Wang, Tao; Navarro-Alvarez, Nalu; Tang, Li-Jun

    2016-01-01

    Liver regeneration is usually attributed to mature hepatocytes, which possess a remarkable potential to proliferate under mild to moderate injury. However, when the liver is severely damaged or hepatocyte proliferation is greatly inhibited, liver stem/progenitor cells (LSPCs) will contribute to the liver regeneration process. LSPCs in the developing liver have been extensively characterized, however, their contributing role to liver regeneration has not been completely understood. In addition to the restoration of the liver parenchymal tissue by hepatocytes or/and LSPCs, or in some cases bone marrow (BM) derived cells, such as hematopoietic stem cells (HSCs) and mesenchymal stem cells (MSCs), the wound healing after injury in terms of angiopoiesis by liver sinusoidal endothelial cells (LSECs) or/and sinusoidal endothelial progenitor cells (SEPCs) is another important aspect taking place during regeneration. To conclude, liver regeneration can be mainly divided into three distinct restoring levels according to the cause and severity of injury: hepatocyte dominant regeneration, LSPCs mediated regeneration, extrahepatic stem cells participative regeneration. In this review, we focus on the recent findings of liver regeneration, especially on those related to stem/progenitor cells (SPCs)-mediated regeneration and their potential clinical applications and challenges. PMID:27489499

  3. The Involving Roles of Intrahepatic and Extrahepatic Stem/Progenitor Cells (SPCs) to Liver Regeneration

    PubMed Central

    Liu, Wei-hui; Ren, Li-na; Wang, Tao; Navarro-Alvarez, Nalu; Tang, Li-jun

    2016-01-01

    Liver regeneration is usually attributed to mature hepatocytes, which possess a remarkable potential to proliferate under mild to moderate injury. However, when the liver is severely damaged or hepatocyte proliferation is greatly inhibited, liver stem/progenitor cells (LSPCs) will contribute to the liver regeneration process. LSPCs in the developing liver have been extensively characterized, however, their contributing role to liver regeneration has not been completely understood. In addition to the restoration of the liver parenchymal tissue by hepatocytes or/and LSPCs, or in some cases bone marrow (BM) derived cells, such as hematopoietic stem cells (HSCs) and mesenchymal stem cells (MSCs), the wound healing after injury in terms of angiopoiesis by liver sinusoidal endothelial cells (LSECs) or/and sinusoidal endothelial progenitor cells (SEPCs) is another important aspect taking place during regeneration. To conclude, liver regeneration can be mainly divided into three distinct restoring levels according to the cause and severity of injury: hepatocyte dominant regeneration, LSPCs mediated regeneration, extrahepatic stem cells participative regeneration. In this review, we focus on the recent findings of liver regeneration, especially on those related to stem/progenitor cells (SPCs)-mediated regeneration and their potential clinical applications and challenges. PMID:27489499

  4. BubR1 Insufficiency Impairs Liver Regeneration in Aged Mice after Hepatectomy through Intercalated Disc Abnormality.

    PubMed

    Ikawa-Yoshida, Ayae; Matsumoto, Takuya; Okano, Shinji; Aoyagi, Yukihiko; Matsubara, Yutaka; Furuyama, Tadashi; Nakatsu, Yoshimichi; Tsuzuki, Teruhisa; Onimaru, Mitsuho; Ohkusa, Tomoko; Nomura, Masatoshi; Maehara, Yoshihiko

    2016-01-01

    A delay in liver regeneration after partial hepatectomy (PHx) leads to acute liver injury, and such delays are frequently observed in aged patients. BubR1 (budding uninhibited by benzimidazole-related 1) controls chromosome mitotic segregation through the spindle assembly checkpoint, and BubR1 down-regulation promotes aging-associated phenotypes. In this study we investigated the effects of BubR1 insufficiency on liver regeneration in mice. Low-BubR1-expressing mutant (BubR1(L/L)) mice had a delayed recovery of the liver weight-to-body weight ratio and increased liver deviation enzyme levels after PHx. Microscopic observation of BubR1(L/L) mouse liver showed an increased number of necrotic hepatocytes and intercalated disc anomalies, resulting in widened inter-hepatocyte and perisinusoidal spaces, smaller hepatocytes and early-stage microvilli atrophy. Up-regulation of desmocollin-1 (DSC1) was observed in wild-type, but not BubR1(L/L), mice after PHx. In addition, knockdown of BubR1 expression caused down-regulation of DSC1 in a human keratinocyte cell line. BubR1 insufficiency results in the impaired liver regeneration through weakened microstructural adaptation against PHx, enhanced transient liver failure and delayed hepatocyte proliferation. Thus, our data suggest that a reduction in BubR1 levels causes failure of liver regeneration through the DSC1 abnormality. PMID:27561386

  5. BubR1 Insufficiency Impairs Liver Regeneration in Aged Mice after Hepatectomy through Intercalated Disc Abnormality

    PubMed Central

    Ikawa-Yoshida, Ayae; Matsumoto, Takuya; Okano, Shinji; Aoyagi, Yukihiko; Matsubara, Yutaka; Furuyama, Tadashi; Nakatsu, Yoshimichi; Tsuzuki, Teruhisa; Onimaru, Mitsuho; Ohkusa, Tomoko; Nomura, Masatoshi; Maehara, Yoshihiko

    2016-01-01

    A delay in liver regeneration after partial hepatectomy (PHx) leads to acute liver injury, and such delays are frequently observed in aged patients. BubR1 (budding uninhibited by benzimidazole-related 1) controls chromosome mitotic segregation through the spindle assembly checkpoint, and BubR1 down-regulation promotes aging-associated phenotypes. In this study we investigated the effects of BubR1 insufficiency on liver regeneration in mice. Low-BubR1-expressing mutant (BubR1L/L) mice had a delayed recovery of the liver weight-to-body weight ratio and increased liver deviation enzyme levels after PHx. Microscopic observation of BubR1L/L mouse liver showed an increased number of necrotic hepatocytes and intercalated disc anomalies, resulting in widened inter-hepatocyte and perisinusoidal spaces, smaller hepatocytes and early-stage microvilli atrophy. Up-regulation of desmocollin-1 (DSC1) was observed in wild-type, but not BubR1L/L, mice after PHx. In addition, knockdown of BubR1 expression caused down-regulation of DSC1 in a human keratinocyte cell line. BubR1 insufficiency results in the impaired liver regeneration through weakened microstructural adaptation against PHx, enhanced transient liver failure and delayed hepatocyte proliferation. Thus, our data suggest that a reduction in BubR1 levels causes failure of liver regeneration through the DSC1 abnormality. PMID:27561386

  6. miR-382 targeting PTEN-Akt axis promotes liver regeneration

    PubMed Central

    Wang, Fei; Dimitrova-Shumkovska, Jasmina; Xiang, Yang; Zhao, Yingying; Liu, Jingqi; Xiao, Junjie; Yang, Changqing

    2016-01-01

    Liver regeneration is a highly orchestrated process which can be regulated by microRNAs (miRNAs, miRs), though the mechanisms are largely unclear. This study was aimed to identify miRNAs responsible for hepatocyte proliferation during liver regeneration. Here we detected a marked elevation of miR-382 in the mouse liver at 48 hrs after partial hepatectomy (PH-48h) using microarray analysis and qRT-PCRs. miR-382 overexpression accelerated the proliferation and the G1 to S phase transition of the cell cycle both in mouse NCTC1469 and human HL7702 normal liver cells, while miR-382 downregulation had inverse effects. Moreover, miR-382 negatively regulated PTEN expression and increased Akt phosphorylation both in vitro and in vivo. Using PTEN siRNA and Akt activator/inhibitor, we further found that PTEN inhibition and Akt phosphorylation were essential for mediating the promotive effect of miR-382 in the proliferation and cell growth of hepatocytes. Collectively, our findings identify miR-382 as a promoter for hepatocyte proliferation and cell growth via targeting PTEN-Akt axis which might be a novel therapeutic target to enhance liver regeneration capability. PMID:26636539

  7. Microbiota and bile acid profiles in retinoic acid-primed mice that exhibit accelerated liver regeneration

    PubMed Central

    Liu, Hui-Xin; Hu, Ying; Wan, Yu-Jui Yvonne

    2016-01-01

    Background & Aims All-trans Retinoic acid (RA) regulates hepatic lipid and bile acid homeostasis. Similar to bile acid (BA), RA accelerates partial hepatectomy (PHx)-induced liver regeneration. Because there is a bidirectional regulatory relationship between gut microbiota and BA synthesis, we examined the effect of RA in altering the gut microbial population and BA composition and established their relationship with hepatic biological processes during the active phases of liver regeneration. Methods C57BL/6 mice were treated with RA orally followed by 2/3 PHx. The roles of RA in shifting gut microbiota and BA profiles as well as hepatocyte metabolism and proliferation were studied. Results RA-primed mice exhibited accelerated hepatocyte proliferation revealed by higher numbers of Ki67-positive cells compared to untreated mice. Firmicutes and Bacteroidetes phyla dominated the gut microbial community (>85%) in both control and RA-primed mice after PHx. RA reduced the ratio of Firmicutes to Bacteroidetes, which was associated with a lean phenotype. Consistently, RA-primed mice lacked transient lipid accumulation normally found in regenerating livers. In addition, RA altered BA homeostasis and shifted BA profiles by increasing the ratio of hydrophilic to hydrophobic BAs in regenerating livers. Accordingly, metabolic regulators fibroblast growth factor 21, Sirtuin1, and their downstream targets AMPK and ERK1/2 were more robustly activated in RA-primed than unprimed regenerating livers. Conclusions Priming mice with RA resulted in a lean microbiota composition and hydrophilic BA profiles, which were associated with facilitated metabolism and enhanced cell proliferation. PMID:26701854

  8. Advances in Liver Regeneration: Revisiting Hepatic Stem/Progenitor Cells and Their Origin.

    PubMed

    Sadri, Ali-Reza; Jeschke, Marc G; Amini-Nik, Saeid

    2016-01-01

    The liver has evolved to become a highly plastic organ with extraordinary regenerative capabilities. What drives liver regeneration is still being debated. Adult liver stem/progenitor cells have been characterized and used to produce functional hepatocytes and biliary cells in vitro. However, in vivo, numerous studies have questioned whether hepatic progenitor cells have a significant role in liver regeneration. Mature hepatocytes have recently been shown to be more plastic than previously believed and give rise to new hepatocytes after acute and chronic injury. In this review, we discuss current knowledge in the field of liver regeneration and the importance of the serotonin pathway as a clinical target for patients with liver dysfunction.

  9. Re-utilization of pyrimidine nucleotides during rat liver regeneration.

    PubMed Central

    Nikolov, E N; Dabeva, M D

    1985-01-01

    The changes in the specific radioactivities of the pool of total acid-soluble uridine nucleotides and of uridine and cytidine components of total cellular and nuclear RNA were monitored in regenerating rat liver for 12 days after partial hepatectomy. Evidence is presented for the re-utilization of pyrimidine nucleotides derived from cytoplasmic RNA degradation for the synthesis of new RNA. The extent of recycling was assessed and the true rate of rRNA turnover determined more accurately. The reutilization of the uridine components of RNA was 7.0%/day during the proliferative and 3.2%/day during the post-proliferative phase, whereas that of the cytidine nucleotides was more pronounced (9.6%/day and 18.1%/day respectively). The results reveal the existence of partial compartmentalization of pyrimidine ribonucleoside triphosphate pools in the nucleus and cytoplasm of rat liver cells. PMID:2408609

  10. MicroRNA-21 Contributes to Liver Regeneration by Targeting PTEN

    PubMed Central

    Chen, Xiaoyu; Song, Meiyi; Chen, Wei; Dimitrova-Shumkovska, Jasmina; Zhao, Yingying; Cao, Yan; Song, Yang; Yang, Wenzhuo; Wang, Fei; Xiang, Yang; Yang, Changqing

    2016-01-01

    Background Multiple microRNAs (miRNAs, miRs), including miR-21, have been documented to be critical regulators of liver regeneration, but the mechanism underlying their roles in hepatocyte proliferation and cell cycle progression is still far from understood. Material/Methods miR-21 levels were determined using qRT-PCRs in mouse livers at 48 h after 70% partial hepatectomy (PH-48 h). Cell proliferation was determined by use of a cell-counting kit-8 (CCK-8), EdU incorporation staining, and flow cytometry. Phosphatase and tensin homolog (PTEN) expressions were determined using qRT-PCR and Western blot analysis. PTEN siRNA was used to perform the rescue experiment. Results A marked upregulation of miR-21 was observed in mouse livers at 48 h after 70% partial hepatectomy (PH-48 h) compared to 0 h after PH (PH-0 h). Overexpression of miR-21 was associated with increased proliferation and a rapid G1-to-S phase transition of the cell cycle in BNL CL.2 normal liver cells in vitro. In addition, we showed that PTEN expression was inversely correlated with miR-21 in BNL CL.2 cells and demonstrated that PTEN expression is lower in mouse livers at PH-48 h. Moreover, the presence of PTEN siRNA significantly abolished the suppressive effect of miR-21 inhibitor on hepatocyte proliferation. Conclusions miR-21 overexpression contributes to liver regeneration and hepatocyte proliferation by targeting PTEN. Upregulation of miR-21 might be a useful therapeutic strategy to promote liver regeneration. PMID:26744142

  11. Lack of mitochondrial topoisomerase I (TOP1mt) impairs liver regeneration.

    PubMed

    Khiati, Salim; Baechler, Simone A; Factor, Valentina M; Zhang, Hongliang; Huang, Shar-yin N; Dalla Rosa, Ilaria; Sourbier, Carole; Neckers, Leonard; Thorgeirsson, Snorri S; Pommier, Yves

    2015-09-01

    The liver has an exceptional replicative capacity following partial hepatectomy or chemical injuries. Cellular proliferation requires increased production of energy and essential metabolites, which critically depend on the mitochondria. To determine whether Top1mt, the vertebrate mitochondrial topoisomerase, is involved in this process, we studied liver regeneration after carbon tetrachloride (CCl4) administration. TOP1mt knockout (KO) mice showed a marked reduction in regeneration and hepatocyte proliferation. The hepatic mitochondrial DNA (mtDNA) failed to increase during recovery from CCl4 exposure. Reduced glutathione was also depleted, indicating increased reactive oxygen species (ROS). Steady-state levels of ATP, O2 consumption, mtDNA, and mitochondrial mass were also reduced in primary hepatocytes from CCl4-treated KO mice. To further test whether Top1mt acted by enabling mtDNA regeneration, we tested TOP1mt KO fibroblasts and human colon carcinoma HCT116 cells and measured mtDNA after 3-d treatment with ethidium bromide. Both types of TOP1mt knockout cells showed defective mtDNA regeneration following mtDNA depletion. Our study demonstrates that Top1mt is required for normal mtDNA homeostasis and for linking mtDNA expansion with hepatocyte proliferation. PMID:26305952

  12. Lack of mitochondrial topoisomerase I (TOP1mt) impairs liver regeneration

    PubMed Central

    Khiati, Salim; Baechler, Simone A.; Factor, Valentina M.; Zhang, Hongliang; Huang, Shar-yin N.; Dalla Rosa, Ilaria; Sourbier, Carole; Neckers, Leonard; Thorgeirsson, Snorri S.; Pommier, Yves

    2015-01-01

    The liver has an exceptional replicative capacity following partial hepatectomy or chemical injuries. Cellular proliferation requires increased production of energy and essential metabolites, which critically depend on the mitochondria. To determine whether Top1mt, the vertebrate mitochondrial topoisomerase, is involved in this process, we studied liver regeneration after carbon tetrachloride (CCl4) administration. TOP1mt knockout (KO) mice showed a marked reduction in regeneration and hepatocyte proliferation. The hepatic mitochondrial DNA (mtDNA) failed to increase during recovery from CCl4 exposure. Reduced glutathione was also depleted, indicating increased reactive oxygen species (ROS). Steady-state levels of ATP, O2 consumption, mtDNA, and mitochondrial mass were also reduced in primary hepatocytes from CCl4-treated KO mice. To further test whether Top1mt acted by enabling mtDNA regeneration, we tested TOP1mt KO fibroblasts and human colon carcinoma HCT116 cells and measured mtDNA after 3-d treatment with ethidium bromide. Both types of TOP1mt knockout cells showed defective mtDNA regeneration following mtDNA depletion. Our study demonstrates that Top1mt is required for normal mtDNA homeostasis and for linking mtDNA expansion with hepatocyte proliferation. PMID:26305952

  13. The Hippo signaling pathway in liver regeneration and tumorigenesis.

    PubMed

    Hong, Lixin; Cai, Yabo; Jiang, Mingting; Zhou, Dawang; Chen, Lanfen

    2015-01-01

    The Hippo signaling pathway is an evolutionarily conserved signaling module that plays critical roles in liver size control and tumorigenesis. The Hippo pathway consists of a core kinase cascade in which the mammalian Ste20-like kinases (Mst1/2, orthologs of Drosophila Hippo) and their cofactor Salvador (Sav1) form a complex to phosphorylate and activate the large tumor suppressor (Lats1/2). Lats1/2 kinases in turn phosphorylate and inhibit the transcription co-activators, the Yes-associated protein (YAP) and the transcriptional co-activator with PDZ-binding motif (TAZ), two major downstream effectors of the Hippo pathway. Losses of the Hippo pathway components induce aberrant hepatomegaly and tumorigenesis, in which YAP coordinates regulation of cell proliferation and apoptosis and plays an essential role. This review summarizes the current findings of the regulation of Hippo signaling in liver regeneration and tumorigenesis, focusing on how the loss of tumor suppressor components of the Hippo pathway results in liver cancers and discussing the molecular mechanisms that regulate the expression and activation of its downstream effector YAP in liver tumorigenesis.

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

    PubMed Central

    Li, Guodong; L. Guo, Grace

    2015-01-01

    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. PMID:26579433

  15. A natural process of cirrhosis resolution and deceleration of liver regeneration after thioacetamide withdrawal in a rat model.

    PubMed

    Gu, Ke; Zhao, Jian-Dong; Ren, Zhi-Gang; Ma, Ning-Yi; Lai, Song-Tao; Wang, Jian; Liu, Jin; Jiang, Guo-Liang

    2011-03-01

    Characteristics of thioacetamide (TAA)-induced liver cirrhosis in rat was observed for 120 days after TAA withdrawal as part of the radiobiological study of partial liver irradiation on TAA-induced cirrhotic rats. The natural process focused on cirrhosis and regeneration was recorded as a baseline condition for the interpretation of the outcome of the partial liver irradiation study. Cirrhosis in rats was successfully induced by drinking 0.03% TAA water orally for 29 weeks with a modeling rate of 96%. After establishment of the cirrhosis model, the rats were observed for 120 days upon TAA withdrawal to investigate the dynamic changes of cirrhosis and regeneration. The following characteristics were observed: (1) Histological changes; (2) Liver functions; (3) Cirrhosis: trichrome stain, quantification of hydroxyproline in hydrolysed liver tissue and TGF-β1; (4) Liver regeneration: liver index, hepatocyte mitotic index (MI), hepatocyte proliferation index (PI) by flow cytometry, PCNA labeling index (LI) by IHC and expression of PCNA mRNA; and (5) Growth factors: serum HGF, VEGF, TGF-α, and IL-6. After TAA withdrawal, gradual improvement in liver functions was noted with decreases of ALT, AST, and ALP, and increase of PA. The resolution of cirrhosis was evident by histological improvement with attenuation of collagen fiber and decrease of TGF-β1 IHC index, and also decrease of trichrome stain and hydroxyproline content. However, cirrhosis was still existed on 120 days after TAA withdrawal. Significant deceleration of liver regeneration was demonstrated with TAA withdrawal, evidenced by decrease of MI and PI, reduced expression of PCNA mRNA and PCNA LI. In conclusion, upon TAA withdrawal hepatic cirrhosis was continuously resolved, but persisted up to 120 days, and liver regeneration was significantly decelerated.

  16. Gene expression profiling analysis of 5-hydroxytryptamine signaling pathway in rat regenerating liver and different types of liver cells.

    PubMed

    Chang, C F; Yang, J; Zhao, W M; Li, Y; Guo, P J; Li, M H; Zhou, Y; Xu, C S

    2015-01-01

    We examined the gene expression profiles of the 5-hydroxytryptamine signaling pathway in the regenerating liver and 8 types of liver cells during rat liver regeneration, and explored expression differences in 5-hydroxytryptamine signaling pathway genes at the level of tissues and cells, as well as the role of the pathway on liver regeneration. Eight types of rat regenerating liver cells were isolated using Percoll density-gradient centrifugation and immunomagnetic bead methods. Rat Genome 230 2.0 Array was used to detect expression changes in 5-hydroxytryptamine signaling pathway genes. The results showed that 26, 47, 8, 21, 16, 19, 22, 27, and 20 genes changed significantly in hepatocytes, biliary epithelial cells, hepatic stellate cells, oval cells, sinusoidal endothelial cells, Kupffer cells, pit cells, dendritic cells, and the regenerating liver, respectively. Synthetic effects of 5-hydroxytryptamine signaling pathway genes in 8 types of liver cells showed that 26 genes were expressed significantly; the expression trends of 10 genes were the same in the regenerating liver, while others were different. Based on the gene expression profiles of the 8 types of liver cells, 5-hydroxytryptamine promoted hepatocyte proliferation through the RAS and STAT3 signaling pathways, proliferation and differentiation of sinusoidal endothelial cells through the STAT3 signaling pathway, and proliferation and apoptosis of pit cells through the AKT3 signaling pathway. There were large differences in genes involved in 5-hydroxytryptamine signaling at the tissue and cellular levels; thus, liver regeneration should be studied in-depth at the cellular level to reveal the molecular mechanism of liver regeneration.

  17. Metabolic scaling predicts posthepatectomy liver regeneration after accounting for hepatocyte hypertrophy.

    PubMed

    Young, LeAnne H; Periwal, Vipul

    2016-04-01

    We adapted a mathematical model of posthepatectomy liver regeneration using data from a subset of patients in the Adult-to-Adult Living Donor Liver Transplantation Cohort Study. The original model addressed changes in the number of quiescent, primed, and proliferating cells. Our adapted model takes into account hypertrophy of primed and replicating cells, and it is better able to predict liver volume. In addition, by building off the hypothesis that cell cycle parameters are approximately the same across all mammals, we found that changing only a single parameter characterizing metabolic load could model liver regeneration in 5 species of mammals. In conclusion, we improved a mathematical model of liver regeneration, predicted mammalian liver regeneration based on metabolism, and found correlations between model parameters and physiological measurements from liver donors.

  18. Phenylbutyrate exerts adverse effects on liver regeneration and amino acid concentrations in partially hepatectomized rats.

    PubMed

    Holecek, Milan; Vodenicarovova, Melita

    2016-06-01

    Phenylbutyrate is recommended in urea cycle disorders and liver injury to enhance nitrogen disposal by the urine. However, hypothetically there may be adverse responses to the use of phenylbutyrate in the treatment of liver disease because of its role as a histone deacetylase inhibitor and its stimulatory effect on branched-chain alpha-keto acid dehydrogenase, the rate-limiting enzyme in the catabolism of branched-chain amino acids (BCAA; valine, leucine and isoleucine). We report the effects of phenylbutyrate on liver regeneration and amino acid levels in plasma of partially hepatectomized (PH) rats. Phenylbutyrate or saline was administered at 12-h intervals to PH or laparotomized rats. Phenylbutyrate delayed the onset of liver regeneration compared to the saline-treated controls, as indicated by lower hepatic DNA specific activities 18 and 24( ) h post-PH, decreased hepatic fractional protein synthesis rates 24 h post-PH and lowered the increases in liver weights and hepatic protein and DNA contents 48 h after PH. Hepatic DNA fragmentation (a hallmark of apoptosis) was higher in the phenylbutyrate-treated animals than in controls. Phenylbutyrate decreased the glutamine and BCAA concentrations and the ratio of the BCAA to aromatic amino acids (phenylalanine and tyrosine) in the blood plasma in both hepatectomized and laparotomized animals. In conclusion, the delayed onset of liver regeneration and the decrease in BCAA/AAA ratio in blood suggest that phenylbutyrate administration may be disastrous in subjects with acute hepatic injury and BCAA supplementation is needed when phenylbutyrate is used therapeutically. PMID:27381898

  19. Fetal and adult liver stem cells for liver regeneration and tissue engineering.

    PubMed

    Fiegel, H C; Lange, Claudia; Kneser, U; Lambrecht, W; Zander, A R; Rogiers, X; Kluth, D

    2006-01-01

    For the development of innovative cell-based liver directed therapies, e.g. liver tissue engineering, the use of stem cells might be very attractive to overcome the limitation of donor liver tissue. Liver specific differentiation of embryonic, fetal or adult stem cells is currently under investigation. Different types of fetal liver (stem) cells during development were identified, and their advantageous growth potential and bipotential differentiation capacity were shown. However, ethical and legal issues have to be addressed before using fetal cells. Use of adult stem cells is clinically established, e.g. transplantation of hematopoietic stem cells. Other bone marrow derived liver stem cells might be mesenchymal stem cells (MSC). However, the transdifferentiation potential is still in question due to the observation of cellular fusion in several in vivo experiments. In vitro experiments revealed a crucial role of the environment (e.g. growth factors and extracellular matrix) for specific differentiation of stem cells. Co-cultured liver cells also seemed to be important for hepatic gene expression of MSC. For successful liver cell transplantation, a novel approach of tissue engineering by orthotopic transplantation of gel-immobilized cells could be promising, providing optimal environment for the injected cells. Moreover, an orthotopic tissue engineering approach using bipotential stem cells could lead to a repopulation of the recipients liver with healthy liver and biliary cells, thus providing both hepatic functions and biliary excretion. Future studies have to investigate, which stem cell and environmental conditions would be most suitable for the use of stem cells for liver regeneration or tissue engineering approaches.

  20. SIRT1 controls liver regeneration by regulating BA metabolism through FXR and mTOR signaling

    PubMed Central

    García-Rodríguez, Juan L.; Barbier-Torres, Lucía; Fernández-Álvarez, Sara; Juan, Virginia Gutiérrez-de; Monte, María J.; Halilbasic, Emina; Herranz, Daniel; Álvarez, Luis; Aspichueta, Patricia; Marín, Jose J. G.; Trauner, Michael; Mato, Jose M.; Serrano, Manuel; Beraza, Naiara; Martínez-Chantar, María Luz

    2014-01-01

    Sirtuin1 (SIRT1) regulates central metabolic functions such as lipogenesis, protein synthesis, gluconeogenesis and bile acid (BA) homeostasis through deacetylation. Here, we describe that SIRT1 tightly controls the regenerative response of the liver. We performed partial hepatectomy (PH) to transgenic mice that overexpress SIRT1 (SIRT). SIRT mice showed increased mortality, impaired hepatocyte proliferation, BA accumulation and profuse liver injury after surgery. The damaging phenotype in SIRT mice correlated with impaired FXR activity due to persistent deacetylation and lower protein expression that led to decreased FXR-target gene expression; SHP, BSEP and increased Cyp7A1. Next, we convincingly show that 24-norUrsodeoxycholic acid (NorUDCA) attenuates SIRT protein expression, increases the acetylation of FXR and neighboring histones, restores trimethylation of H3K4 and H3K9 and increases miR34a expression, thus re-establishing BA homeostasis. Consequently, NorUDCA restored liver regeneration in SIRT mice, which showed increased survival and hepatocyte proliferation. Furthermore, a Leucine-enriched diet restored mTOR activation, acetylation of FXR and histones, leading to an overall lower BA production through SHP-inhibition of Cyp7A1 and higher transport (BSEP) and detoxification (Sult2a1) leading to an improved liver regeneration. Finally, we found that human HCC samples have increased presence of SIRT1, which correlated with absence of FXR suggesting its oncogenic potential. Conclusions Overall, we define SIRT1 as a key regulator of the regenerative response in the liver through post-transcriptional modifications that regulate the activity of FXR, histones and mTOR. Moreover, our data suggest that SIRT1 contributes to liver tumorigenesis through dysregulation of BA homeostasis by persistent FXR deacetylation. PMID:24338587

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

    SciTech Connect

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

    1985-08-01

    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 /sup 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.

  2. MicroRNA125b-mediated Hedgehog signaling influences liver regeneration by chorionic plate-derived mesenchymal stem cells.

    PubMed

    Hyun, Jeongeun; Wang, Sihyung; Kim, Jieun; Kim, Gi Jin; Jung, Youngmi

    2015-09-15

    Although chorionic plate-derived mesenchymal stem cells (CP-MSCs) were shown to promote liver regeneration, the mechanisms underlying the effect remain unclear. Hedgehog (Hh) signaling orchestrates tissue reconstruction in damaged liver. MSCs release microRNAs mediating various cellular responses. Hence, we hypothesized that microRNAs from CP-MSCs regulated Hh signaling, which influenced liver regeneration. Livers were obtained from carbon tetrachloride (CCl4)-treated rats transplanted with human CP-MSCs (Tx) or saline (non-Tx). Sonic Hh, one of Hh ligands, increased in CCl4-treated liver, whereas it decreased in CP-MSC-treated liver with CCl4. The expression of Hh-target genes was significantly downregulated in the Tx. Reduced expansion of progenitors and regressed fibrosis were observed in the liver of the Tx rats. CP-MSCs suppressed the expression of Hh and profibrotic genes in co-cultured LX2 (human hepatic stellate cell) with CP-MSCs. MicroRNA-125b targeting smo was retained in exosomes of CP-MSCs. CP-MSCs with microRNA-125b inhibitor failed to attenuate the expression of Hh signaling and profibrotic genes in the activated HSCs. Therefore, these results demonstrated that microRNA-125b from CP-MSCs suppressed the activation of Hh signaling, which promoted the reduced fibrosis, suggesting that microRNA-mediated regulation of Hh signaling contributed to liver regeneration by CP-MSCs.

  3. Control of tissue growth by locally produced activator: Liver regeneration

    NASA Astrophysics Data System (ADS)

    Zhdanov, Vladimir P.

    2015-03-01

    In general, the tissue development is controlled by growth factors and depends on the biomechanics of cells. The corresponding kinetic models are focused primarily on the early stages of the development. The attempts to construct such models for the later stages are still rare. One of the notable examples here is liver regeneration. Referring to this process, the author proposes and analyzes a generic kinetic model describing the regulation of tissue growth by locally produced activator. The model includes activator diffusion and control of the rate of cell proliferation which is described by using the Hill expression. Although this control may be moderately or strongly non-linear, the qualitative changes in the regeneration kinetics are predicted to be modest. For moderately non-linear control, the evolution of the tissue volume to the steady-state value exhibits an initial relatively short linear stage and then becomes slightly slower so that the whole kinetics is close to exponential. For strongly non-linear control, the linear stage dominates and/or the kinetics may exhibit a S-like shape feature which is, however, rather weak. The identification of such qualitative features in experimentally measured kinetics is shown to be difficult, because the error bars in the experiments are typically too large.

  4. Effect of Boron Neutron Capture Therapy (BNCT) on Normal Liver Regeneration: Towards a Novel Therapy for Liver Metastases

    SciTech Connect

    Jorge E. Cardoso; Elisa M. Heber; David W. Nigg; Osvaldo Calzetta; Herman Blaumann; Juan Longhino; Maria E. Itoiz; Eduardo Bumaschny; Emiliano Pozzi; Amanda E.Schwint; Verónica A. Trivillin

    2007-10-01

    The “TAORMINA project” developed a new method for Boron Neutron Capture Therapy (BNCT) of human multifocal unresectable liver metastases based on whole liver ex-situ BNCT mediated by boronophenylalanine (BPA), followed by whole liver autograft. This technique involved a high risk, prolonged anhepatic phase. The Roffo Institute liver surgeons (JEC) herein propose a novel technique to pursue ex-situ liver BNCT studies with a drastically lower surgical risk for the patient. The technique would involve, sequentially, ex-situ BNCT of left liver segments II and III, partial liver autograft, and induction of partial atrophy of the untreated right liver. The working hypothesis is that the atrophy of the right, untreated, diseased liver would stimulate regeneration of the left, treated, “cured” liver to yield a healthy liver mass, allowing for the resection of the remaining portion of diseased liver. This technique does not involve an anhepatic phase and would thus pose a drastically lower surgical risk to the patient but requires sine qua non that BNCT should not impair the regenerative capacity of normal hepatocytes. The aim of the present study was to assess the effect of therapeutic doses of BNCT mediated by BPA, GB-10 (Na2 10B10H10) or (GB- 10 + BPA) on normal liver regeneration in the Wistar rat employing partial hepatectomy as a regenerative stimulus. BNCT did not cause alterations in the outcome of normal liver regeneration, regenerated liver function or histology. We provide proof of principle to support the development of a novel, promising BNCT technique for the treatment of liver metastases.

  5. Fluorodeoxyglucose Positron Emission Tomography Response and Normal Tissue Regeneration After Stereotactic Body Radiotherapy to Liver Metastases

    SciTech Connect

    Stinauer, Michelle A.; Diot, Quentin; Westerly, David C.; Schefter, Tracey E.; Kavanagh, Brian D.

    2012-08-01

    Purpose: To characterize changes in standardized uptake value (SUV) in positron emission tomography (PET) scans and determine the pace of normal tissue regeneration after stereotactic body radiation therapy (SBRT) for solid tumor liver metastases. Methods and Materials: We reviewed records of patients with liver metastases treated with SBRT to {>=}40 Gy in 3-5 fractions. Evaluable patients had pretreatment PET and {>=}1 post-treatment PET. Each PET/CT scan was fused to the planning computed tomography (CT) scan. The maximum SUV (SUV{sub max}) for each lesion and the total liver volume were measured on each PET/CT scan. Maximum SUV levels before and after SBRT were recorded. Results: Twenty-seven patients with 35 treated liver lesions were studied. The median follow-up was 15.7 months (range, 1.5-38.4 mo), with 5 PET scans per patient (range, 2-14). Exponential decay curve fitting (r=0.97) showed that SUV{sub max} declined to a plateau of 3.1 for controlled lesions at 5 months after SBRT. The estimated SUV{sub max} decay half-time was 2.0 months. The SUV{sub max} in controlled lesions fluctuated up to 4.2 during follow-up and later declined; this level is close to 2 standard deviations above the mean normal liver SUV{sub max} (4.01). A failure cutoff of SUV{sub max} {>=}6 is twice the calculated plateau SUV{sub max} of controlled lesions. Parenchymal liver volume decreased by 20% at 3-6 months and regenerated to a new baseline level approximately 10% below the pretreatment level at 12 months. Conclusions: Maximum SUV decreases over the first months after SBRT to plateau at 3.1, similar to the median SUV{sub max} of normal livers. Transient moderate increases in SUV{sub max} may be observed after SBRT. We propose a cutoff SUV{sub max} {>=}6, twice the baseline normal liver SUV{sub max}, to score local failure by PET criteria. Post-SBRT values between 4 and 6 would be suspicious for local tumor persistence or recurrence. The volume of normal liver reached nadir 3

  6. Adaptive tolerance in mice upon subchronic exposure to chloroform: Increased exhalation and target tissue regeneration

    SciTech Connect

    Anand, Sathanandam S. . E-mail: sanand@rx.uga.edu; Philip, Binu K.; Palkar, Prajakta S.; Mumtaz, Moiz M.; Latendresse, John R.; Mehendale, Harihara M. . E-mail: mehendale@ulm.edu

    2006-06-15

    The aims of the present study were to characterize the subchronic toxicity of chloroform by measuring tissue injury, repair, and distribution of chloroform and to assess the reasons for the development of tolerance to subchronic chloroform toxicity. Male Swiss Webster (SW) mice were given three dose levels of chloroform (150, 225, and 300 mg/kg/day) by gavage in aqueous vehicle for 30 days. Liver and kidney injury were measured by plasma ALT and BUN, respectively, and by histopathology. Tissue regeneration was assessed by {sup 3}H-thymidine incorporation into hepato- and nephro-nuclear DNA and by proliferating cell nuclear antigen staining. In addition, GSH and CYP2E1 in liver and kidney were assessed at selected time points. The levels of chloroform were measured in blood, liver, and kidney during the dosing regimen (1, 7, 14, and 30 days). Kidney injury was evident after 1 day with all three doses and sustained until 7 days followed by complete recovery. Mild to moderate liver injury was observed from 1 to 14 days with all three dose levels followed by gradual decrease. Significantly higher regenerative response was evident in liver and kidney at 7 days, but the response was robust in kidney, preventing progression of injury beyond first week of exposure. While the kidney regeneration reached basal levels by 21 days, moderate liver regeneration with two higher doses sustained through the end of the dosing regimen and 3 days after that. Following repeated exposure for 7, 14, and 30 days, the blood and tissue levels of chloroform were substantially lower with all three dose levels compared to the levels observed with single exposure. Increased exhalation of {sup 14}C-chloroform after repeated exposures explains the decreased chloroform levels in circulation and tissues. These results suggest that toxicokinetics and toxicodynamics (tissue regeneration) contribute to the tolerance observed in SW mice to subchronic chloroform toxicity. Neither bioactivation nor

  7. Impact of splenic artery ligation after major hepatectomy on liver function, regeneration and viability

    PubMed Central

    Carrapita, Jorge; Abrantes, Ana Margarida; Campelos, Sofia; Gonçalves, Ana Cristina; Cardoso, Dulce; Sarmento-Ribeiro, Ana Bela; Rocha, Clara; Santos, Jorge Nunes; Botelho, Maria Filomena; Tralhão, José Guilherme; Farges, Olivier; Barbosa, Jorge Maciel

    2016-01-01

    It was reported that prevention of acute portal overpressure in small-for-size livers by inflow modulation results in a better postoperative outcome. The aim is to investigate the impact of portal blood flow reduction by splenic artery ligation after major hepatectomy in a murine model. Forty-eight rats were subjected to an 85% hepatectomy or 85% hepatectomy and splenic artery ligation. Both groups were evaluated at 24, 48, 72 and 120 post-operative hours: liver function, regeneration and viability. All methods and experiments were carried out in accordance with Coimbra University guidelines. Splenic artery ligation produces viability increase after 24 h, induces a relative decrease in oxidative stress during the first 48 hours, allows antioxidant capacity increment after 24 h, which is reflected in a decrease of half-time normalized liver curve at 48 h and at 72 h and in an increase of mitotic index between 48 h and 72 h. Splenic artery ligation combined with 85% hepatectomy in a murine model, allows portal inflow modulation, promoting an increase in hepatocellular viability and regeneration, without impairing the function, probably by inducing a less marked elevation of oxidative stress at first 48 hours. PMID:27725728

  8. [Thiamine pyrophosphate-dependent enzymes in the regenerating liver of albino rats under different regimens of oxythiamine administration].

    PubMed

    Kravchuk, R I

    1985-01-01

    Activities of the thiamine pyrophosphate-dependent enzymes (pyruvate dehydrogenase, oxoglutarate dehydrogenase, transketolase) were increased in regenerating rat liver tissue as compared with their activities in the intact tissue. After administration of oxythiamine (20 mg/kg, within 10 days, subcutaneously) into the animals the enzymatic activity studied was decreased.

  9. Transforming growth factor alpha may be a physiological regulator of liver regeneration by means of an autocrine mechanism.

    PubMed Central

    Mead, J E; Fausto, N

    1989-01-01

    We investigated whether transforming growth factor alpha (TGF-alpha) is involved in hepatocyte growth responses both in vivo and in culture. During liver regeneration after partial hepatectomy in rats, TGF-alpha mRNA increased; it reached a maximum (approximately 9-fold higher than normal) at the peak of DNA synthesis. The message and the peptide were localized in hepatocytes and found in higher amounts in hepatocytes obtained from regenerating liver. TGF-alpha caused a 13-fold elevation of DNA synthesis in hepatocytes in primary culture and was slightly more effective than epidermal growth factor. TGF-beta blocked TGF-alpha stimulation when added either simultaneously with TGF-alpha or a day later. TGF-alpha message increased in hepatocytes stimulated to undergo DNA synthesis by TGF-alpha or epidermal growth factor, and the peptide was detected in the culture medium by RIA. In the regenerating liver, the increase in TGF-alpha mRNA during the first day after partial hepatectomy coincided with an increase in epidermal growth factor/TGF-alpha receptor mRNA and a decrease (already reported) in the number of these receptors. We conclude that TGF-alpha may function as a physiological inducer of hepatocyte DNA synthesis during liver regeneration by means of an autocrine mechanism and that its stimulatory effects in this growth process are balanced by the inhibitory action of TGF-beta 1. Images PMID:2922399

  10. Fructus polygoni orentalis extract inhibited liver regeneration and proliferation of bone marrow cells of rat after partial hepatectomy.

    PubMed

    Yang, J Y; Wang, J S; Liu, H B

    2015-01-01

    To study the effect of fructus polygoni orentalis extract (EFPO) on liver regeneration and proliferation of bone marrow cells on rat model of partial hepatectomy, EFPO was extracted, and 60 adult male Wistar rats were divided randomly into 6 experimental groups. Rats were treated with intergastric administration (ig) with EFPO daily. All rats were euthanized 7 days after administration, and the livers and bone marrow cells were collected. The levels of taxifolin and quercetin in EFPO were 1.238 and 0.381 mg/g, respectively. EFPO decreased the proliferating cell nuclear antigen expression of the regenerating liver. Obvious tissue damage was observed in the EFPO groups, such as a widened hepatic sinusoid cavity, several enlarged nuclei, slightly ballooning degeneration, and spotty and focal necrosis as compared to the control group. Additionally, 1.8 and 3.6 g/kg EFPO significantly inhibited proliferating cell nuclear antigen expression in bone marrows cells (P < 0.05), and induced gathering of these cells during the GO/G1 phases (P < 0.05). The karyocyte and myelosis of bone marrows cells clearly decreased, and mature erythrocytes increased (P < 0.05) in the EFPO groups. Additionally, 3.6 g/kg EFPO induced active proliferation, while the sham operation and control groups showed apparent active myelo-proliferation. The maximum dosage of mice ig EFPO was 148.8 g/kg. Our results indicate that EFPO inhibits rat liver regeneration and bone marrow cell proliferation in regenerating rat liver.

  11. Hepatic Deficiency of Augmenter of Liver Regeneration Exacerbates Alcohol-Induced Liver Injury and Promotes Fibrosis in Mice.

    PubMed

    Kumar, Sudhir; Wang, Jiang; Rani, Richa; Gandhi, Chandrashekhar R

    2016-01-01

    Why only a subpopulation (about 15%) of humans develops liver cirrhosis due to alcohol is a critical as yet unanswered question. Liver-specific depletion of augmenter of liver regeneration (ALR) protein in mice causes robust steatosis and hepatocyte apoptosis by 2 weeks; these pathologies regress subsequently with return of ALR expression even at lower than control levels, but the mice develop modest steatohepatitis by 8 weeks. We aimed to investigate whether chronic alcohol ingestion promotes excessive hepatic fibrosis in these ALR-deficient mice. Liver-specific ALR-deficient and wild type (WT) female mice (8-10 weeks old) were placed on 4% alcohol-supplemented or isocaloric diet for 4 weeks. Liver sections were examined for histopathology, and parameters of steatosis and fibrosis were quantified. The mRNA expression of alcohol dehydrogenase-1, acetaldehyde dehydrogenase-1 and cytochrome P450-2E1 increased in WT mice but decreased in ALR-deficient mice upon alcohol ingestion. While alcohol induced steatosis and mild inflammation in WT mice, ALR-deficient mice showed minimal steatosis, strong hepatocellular injury and inflammation, prominent ductular proliferation, and robust fibrosis. Compared to the WT mice, alcohol feeding of ALR-deficient mice resulted in significantly greater increase in hepatic TNFα and TGFβ, and oxidative stress; there was also hepatic iron accumulation, robust lipid peroxidation and mitochondrial DNA damage. Importantly, similar to ALR-deficient mice, lower hepatic ALR levels in human alcoholic liver cirrhosis were associated with increased iron content, reduced expression of alcohol dehydrogenase and acetaldehyde dehydrogenase, and elevated fibrogenic markers. We conclude that ALR deficiency or anomaly can play a critical role in alcohol-induced hepatic fibrosis/cirrhosis, mechanisms of which may involve dysregulation of alcohol metabolism and iron homeostasis, mitochondrial damage and oxidative injury. PMID:26808690

  12. Hepatic Deficiency of Augmenter of Liver Regeneration Exacerbates Alcohol-Induced Liver Injury and Promotes Fibrosis in Mice

    PubMed Central

    Kumar, Sudhir; Wang, Jiang; Rani, Richa; Gandhi, Chandrashekhar R.

    2016-01-01

    Why only a subpopulation (about 15%) of humans develops liver cirrhosis due to alcohol is a critical as yet unanswered question. Liver-specific depletion of augmenter of liver regeneration (ALR) protein in mice causes robust steatosis and hepatocyte apoptosis by 2 weeks; these pathologies regress subsequently with return of ALR expression even at lower than control levels, but the mice develop modest steatohepatitis by 8 weeks. We aimed to investigate whether chronic alcohol ingestion promotes excessive hepatic fibrosis in these ALR-deficient mice. Liver-specific ALR-deficient and wild type (WT) female mice (8–10 weeks old) were placed on 4% alcohol-supplemented or isocaloric diet for 4 weeks. Liver sections were examined for histopathology, and parameters of steatosis and fibrosis were quantified. The mRNA expression of alcohol dehydrogenase-1, acetaldehyde dehydrogenase-1 and cytochrome P450-2E1 increased in WT mice but decreased in ALR-deficient mice upon alcohol ingestion. While alcohol induced steatosis and mild inflammation in WT mice, ALR-deficient mice showed minimal steatosis, strong hepatocellular injury and inflammation, prominent ductular proliferation, and robust fibrosis. Compared to the WT mice, alcohol feeding of ALR-deficient mice resulted in significantly greater increase in hepatic TNFα and TGFβ, and oxidative stress; there was also hepatic iron accumulation, robust lipid peroxidation and mitochondrial DNA damage. Importantly, similar to ALR-deficient mice, lower hepatic ALR levels in human alcoholic liver cirrhosis were associated with increased iron content, reduced expression of alcohol dehydrogenase and acetaldehyde dehydrogenase, and elevated fibrogenic markers. We conclude that ALR deficiency or anomaly can play a critical role in alcohol-induced hepatic fibrosis/cirrhosis, mechanisms of which may involve dysregulation of alcohol metabolism and iron homeostasis, mitochondrial damage and oxidative injury. PMID:26808690

  13. Regenerating the liver: not so simple after all?

    PubMed Central

    Alison, Malcolm R.; Lin, Wey-Ran

    2016-01-01

    Under normal homeostatic conditions, hepatocyte renewal is a slow process and complete turnover likely takes at least a year. Studies of hepatocyte regeneration after a two-thirds partial hepatectomy (2/3 PH) have strongly suggested that periportal hepatocytes are the driving force behind regenerative re-population, but recent murine studies have brought greater complexity to the issue. Although periportal hepatocytes are still considered pre-eminent in the response to 2/3 PH, new studies suggest that normal homeostatic renewal is driven by pericentral hepatocytes under the control of Wnts, while pericentral injury provokes the clonal expansion of a subpopulation of periportal hepatocytes expressing low levels of biliary duct genes such as Sox9 and osteopontin. Furthermore, some clarity has been given to the debate on the ability of biliary-derived hepatic progenitor cells to generate physiologically meaningful numbers of hepatocytes in injury models, demonstrating that under appropriate circumstances these cells can re-populate the whole liver. PMID:27508069

  14. Antioxidative, antiapoptotic, and proliferative effect of curcumin on liver regeneration after partial hepatectomy in rats.

    PubMed

    Toydemir, Toygar; Kanter, Mehmet; Erboga, Mustafa; Oguz, Serhat; Erenoglu, Cengiz

    2015-02-01

    The aim of the present study was to assess the influence of curcumin on liver regeneration after partial hepatectomy (PH) in rats. A total of 24 male Sprague Dawley rats were divided into three groups: sham-operated (SH), PH, and PH + curcumin; each group contains eight animals. The rats in curcumin-treated groups were given curcumin (in a dose of 100 mg/kg body weight) once a day orally for 7 days, starting 3 days prior to hepatectomy operation. At 7 days after resection, liver samples were collected. The malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione (GSH) levels were estimated in liver homogenates. Moreover, histopathological examination, mitotic index (MI), proliferating cell nuclear antigen labeling, proliferation index (PI), transferase-mediated 2'-deoxyuridine, 5'-triphosphate nick end-labeling assay, and apoptotic index (AI) were evaluated at 7 days after hepatectomy. As a result, curcumin significantly increased MI and PI and significantly decreased AI in PH rats. Additionally, curcumin remarkably inhibited MDA elevation, restored impaired antioxidant SOD activity and GSH level and also attenuated hepatic vacuolar degeneration and sinusoidal congestion. These results suggested that curcumin treatment had a beneficial effect on liver regenerative capacity of the remnant liver tissue after hepatectomy, probably due to its antioxidative, antiapoptotic, and proliferative properties.

  15. Divergent angiocrine signals from vascular niche balance liver regeneration and fibrosis.

    PubMed

    Ding, Bi-Sen; Cao, Zhongwei; Lis, Raphael; Nolan, Daniel J; Guo, Peipei; Simons, Michael; Penfold, Mark E; Shido, Koji; Rabbany, Sina Y; Rafii, Shahin

    2014-01-01

    Chemical or traumatic damage to the liver is frequently associated with aberrant healing (fibrosis) that overrides liver regeneration. The mechanism by which hepatic niche cells differentially modulate regeneration and fibrosis during liver repair remains to be defined. Hepatic vascular niche predominantly represented by liver sinusoidal endothelial cells deploys paracrine trophogens, known as angiocrine factors, to stimulate regeneration. Nevertheless, it is not known how pro-regenerative angiocrine signals from liver sinusoidal endothelial cells is subverted to promote fibrosis. Here, by combining an inducible endothelial-cell-specific mouse gene deletion strategy and complementary models of acute and chronic liver injury, we show that divergent angiocrine signals from liver sinusoidal endothelial cells stimulate regeneration after immediate injury and provoke fibrosis after chronic insult. The pro-fibrotic transition of vascular niche results from differential expression of stromal-derived factor-1 receptors, CXCR7 and CXCR4 (refs 18, 19, 20, 21), in liver sinusoidal endothelial cells. After acute injury, CXCR7 upregulation in liver sinusoidal endothelial cells acts with CXCR4 to induce transcription factor Id1, deploying pro-regenerative angiocrine factors and triggering regeneration. Inducible deletion of Cxcr7 in sinusoidal endothelial cells (Cxcr7(iΔEC/iΔEC)) from the adult mouse liver impaired liver regeneration by diminishing Id1-mediated production of angiocrine factors. By contrast, after chronic injury inflicted by iterative hepatotoxin (carbon tetrachloride) injection and bile duct ligation, constitutive FGFR1 signalling in liver sinusoidal endothelial cells counterbalanced CXCR7-dependent pro-regenerative response and augmented CXCR4 expression. This predominance of CXCR4 over CXCR7 expression shifted angiocrine response of liver sinusoidal endothelial cells, stimulating proliferation of desmin(+) hepatic stellate-like cells and enforcing a pro

  16. Postponing the Hypoglycemic Response to Partial Hepatectomy Delays Mouse Liver Regeneration.

    PubMed

    Huang, Jiansheng; Schriefer, Andrew E; Cliften, Paul F; Dietzen, Dennis; Kulkarni, Sakil; Sing, Sucha; Monga, Satdarshan P S; Rudnick, David A

    2016-03-01

    All serious liver injuries alter metabolism and initiate hepatic regeneration. Recent studies using partial hepatectomy (PH) and other experimental models of liver regeneration implicate the metabolic response to hepatic insufficiency as an important source of signals that promote regeneration. Based on these considerations, the analyses reported here were undertaken to assess the impact of interrupting the hypoglycemic response to PH on liver regeneration in mice. A regimen of parenteral dextrose infusion that delays PH-induced hypoglycemia for 14 hours after surgery was identified, and the hepatic regenerative response to PH was compared between dextrose-treated and control mice. The results showed that regenerative recovery of the liver was postponed in dextrose-infused mice (versus vehicle control) by an interval of time comparable to the delay in onset of PH-induced hypoglycemia. The regulation of specific liver regeneration-promoting signals, including hepatic induction of cyclin D1 and S-phase kinase-associated protein 2 expression and suppression of peroxisome proliferator-activated receptor γ and p27 expression, was also disrupted by dextrose infusion. These data support the hypothesis that alterations in metabolism that occur in response to hepatic insufficiency promote liver regeneration, and they define specific pro- and antiregenerative molecular targets whose regenerative regulation is postponed when PH-induced hypoglycemia is delayed.

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

    SciTech Connect

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

    2009-10-02

    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.

  18. Systems Analysis of the Complement-Induced Priming Phase of Liver Regeneration.

    PubMed

    Min, Jun S; DeAngelis, Robert A; Reis, Edimara S; Gupta, Shakti; Maurya, Mano R; Evans, Charles; Das, Arun; Burant, Charles; Lambris, John D; Subramaniam, Shankar

    2016-09-15

    Liver regeneration is a well-orchestrated process in the liver that allows mature hepatocytes to reenter the cell cycle to proliferate and replace lost or damaged cells. This process is often impaired in fatty or diseased livers, leading to cirrhosis and other deleterious phenotypes. Prior research has established the role of the complement system and its effector proteins in the progression of liver regeneration; however, a detailed mechanistic understanding of the involvement of complement in regeneration is yet to be established. In this study, we have examined the role of the complement system during the priming phase of liver regeneration through a systems level analysis using a combination of transcriptomic and metabolomic measurements. More specifically, we have performed partial hepatectomy on mice with genetic deficiency in C3, the major component of the complement cascade, and collected their livers at various time points. Based on our analysis, we show that the C3 cascade activates c-fos and promotes the TNF-α signaling pathway, which then activates acute-phase genes such as serum amyloid proteins and orosomucoids. The complement activation also regulates the efflux and the metabolism of cholesterol, an important metabolite for cell cycle and proliferation. Based on our systems level analysis, we provide an integrated model for the complement-induced priming phase of liver regeneration. PMID:27511733

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

    PubMed Central

    Sipahi, Mesut; Şahin, Sevinç; Arslan, Ergin; Börekci, Hasan; Metin, Bayram; Cantürk, Nuh Zafer

    2015-01-01

    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. PMID:26457000

  20. Proton nuclear magnetic resonance of regenerating rat liver after partial hepatectomy

    SciTech Connect

    de Certaines, J.D.; Moulinoux, J.P.; Benoist, L.; Benard, A.; Rivet, P.

    1982-08-09

    Spin-lattice (T/sub 1/) and spin-spin (T/sub 2/) proton nuclear magnetic resonance relaxation times were measured over a 48-hours period of experimental liver regeneration in Wistar rats, T/sub 2/ showed an early significant increase reaching a plateau 30% above baseline from the 10th hrs onwards. Laparotomized control animals showed no change in T/sub 2/ values. The increase in T/sub 1/ occurred at a later stage but was no different from that in laparotomized controls. T/sub 1/ reached a peak, 20% above baseline, around the 30th hr. The changes observed were far less marked than those previously described for cancer tissue, which showed about a 60% increase in T/sub 1/ fluctuations followed a circadian pattern, with a minimum at night's end and a maximum around mid-day. No circadian rhythm was seen for T/sub 2/. The observed T/sub 1/ and T/sub 2/ changes are discussed with respect to mitotic and metabolic events known to occur during regeneration of the liver.

  1. Protective effect of some vitamins against the toxic action of ethanol on liver regeneration induced by partial hepatectomy in rats

    PubMed Central

    Ramírez-Farías, Carlett; Madrigal-Santillán, Eduardo; Gutiérrez-Salinas, José; Rodríguez-Sánchez, Nidia; Martínez-Cruz, Maricela; Valle-Jones, Ilse; Gramlich-Martínez, Ingrid; Hernández-Ceruelos, Alejandra; Morales-González, José A

    2008-01-01

    AIM: To investigate the effects of vitamins (A, C and E) on liver injury induced by ethanol administration during liver regeneration in rats. METHODS: Male Wistar rats subjected to 70% partial hepatectomy were divided into five groups (groups 1-5). During the experiment, animals of Group 1 drank only water. The other four groups (2-5) drank 30 mL of ethanol/L of water. Group 3 additionally received vitamin A, those of group 4 vitamin C and those of group 5 received vitamin E. Subsequently serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), albumin and bilirubin were measured colorimetrically. Lipid peroxidation (thiobarbituric-acid reactive substances, TBARS) both in plasma and liver was measured, as well as liver mass gain assessment and total DNA. RESULTS: Compared with sham group, serum AST and ALT increased significantly under ethanol treatment (43% and 93%, respectively, with P < 0.05). Vitamin C and vitamin E treatment attenuated the ethanol-induced increases in ALT and AST activity. Ethanol treatment also decreased serum albumin concentration compared to sham group (3.1 ± 0.4 g/dL vs 4.5 ± 0.2 g/dL; P < 0.05). During liver regeneration vitamins C and E significantly ameliorated liver injury for ethanol administration in hepatic lipid peroxidation (4.92 nmol/mg and 4.25 nmol/mg vs 14.78 nmol/mg, respectively, with P < 0.05). In association with hepatic injury, ethanol administration caused a significant increase in both hepatic and plasma lipid peroxidation. Vitamins (C and E) treatment attenuated hepatic and plasma lipid peroxidation. CONCLUSION: Vitamins C and E protect against liver injury and dysfunction, attenuate lipid peroxidation, and thus appear to be significantly more effective than vitamin A against ethanol-mediated toxic effects during liver regeneration. PMID:18240347

  2. Wilson's disease; increased aluminum in liver.

    PubMed

    Yasui, M; Yoshimasu, F; Yase, Y; Uebayashi, Y

    1979-01-01

    Interaction of trace metal metabolism was studied in a patient with Wilson's dease. Atomic absorption analysis showed markedly increased urinary excretion of copper and aluminum and an increased aluminum content was found in the biopsied liver by neutron activation analysis. These findings suggest a complicated pathogenetic mechanism involving other metals besides copper in the Wilson's disease.

  3. Significant lethality following liver resection in A20 heterozygous knockout mice uncovers a key role for A20 in liver regeneration.

    PubMed

    Studer, P; da Silva, C G; Revuelta Cervantes, J M; Mele, A; Csizmadia, E; Siracuse, J J; Damrauer, S M; Peterson, C R; Candinas, D; Stroka, D M; Ma, A; Bhasin, M; Ferran, C

    2015-12-01

    Hepatic expression of A20, including in hepatocytes, increases in response to injury, inflammation and resection. This increase likely serves a hepatoprotective purpose. The characteristic unfettered liver inflammation and necrosis in A20 knockout mice established physiologic upregulation of A20 as integral to the anti-inflammatory and anti-apoptotic armamentarium of hepatocytes. However, the implication of physiologic upregulation of A20 in modulating hepatocytes' proliferative responses following liver resection remains controversial. To resolve the impact of A20 on hepatocyte proliferation and the liver's regenerative capacity, we examined whether decreased A20 expression, as in A20 heterozygous knockout mice, affects outcome following two-third partial hepatectomy. A20 heterozygous mice do not demonstrate a striking liver phenotype, indicating that their A20 expression levels are still sufficient to contain inflammation and cell death at baseline. However, usually benign partial hepatectomy provoked a staggering lethality (>40%) in these mice, uncovering an unsuspected phenotype. Heightened lethality in A20 heterozygous mice following partial hepatectomy resulted from impaired hepatocyte proliferation due to heightened levels of cyclin-dependent kinase inhibitor, p21, and deficient upregulation of cyclins D1, E and A, in the context of worsened liver steatosis. A20 heterozygous knockout minimally affected baseline liver transcriptome, mostly circadian rhythm genes. Nevertheless, this caused differential expression of >1000 genes post hepatectomy, hindering lipid metabolism, bile acid biosynthesis, insulin signaling and cell cycle, all critical cellular processes for liver regeneration. These results demonstrate that mere reduction of A20 levels causes worse outcome post hepatectomy than full knockout of bona fide liver pro-regenerative players such as IL-6, clearly ascertaining A20's primordial role in enabling liver regeneration. Clinical implications of these

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

    PubMed

    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.

  5. Prediction of postoperative liver regeneration from clinical information using a data-led mathematical model

    PubMed Central

    Yamamoto, Kimiyo N.; Ishii, Masatsugu; Inoue, Yoshihiro; Hirokawa, Fumitoshi; MacArthur, Ben D.; Nakamura, Akira; Haeno, Hiroshi; Uchiyama, Kazuhisa

    2016-01-01

    Although the capacity of the liver to recover its size after resection has enabled extensive liver resection, post-hepatectomy liver failure remains one of the most lethal complications of liver resection. Therefore, it is clinically important to discover reliable predictive factors after resection. In this study, we established a novel mathematical framework which described post-hepatectomy liver regeneration in each patient by incorporating quantitative clinical data. Using the model fitting to the liver volumes in series of computed tomography of 123 patients, we estimated liver regeneration rates. From the estimation, we found patients were divided into two groups: i) patients restored the liver to its original size (Group 1, n = 99); and ii) patients experienced a significant reduction in size (Group 2, n = 24). From discriminant analysis in 103 patients with full clinical variables, the prognosis of patients in terms of liver recovery was successfully predicted in 85–90% of patients. We further validated the accuracy of our model prediction using a validation cohort (prediction = 84–87%, n = 39). Our interdisciplinary approach provides qualitative and quantitative insights into the dynamics of liver regeneration. A key strength is to provide better prediction in patients who had been judged as acceptable for resection by current pragmatic criteria. PMID:27694914

  6. Expression of neuritin during liver maturation and regeneration.

    PubMed

    Kojima, Nobuhiko; Shiojiri, Nobuyoshi; Sakai, Yasuyuki; Miyajima, Atsushi

    2005-08-29

    Cell surface molecules are not only important for cell-cell interactions but also useful for a marker to define cell types and differentiation stages. Unlike hematopoietic system in which numerous such antigens have been identified, only a few cell surface molecules have been used to define differentiation stage of hepatocytes. In order to identify such cell surface molecules, we performed DNA microarray analysis using mRNA from fetal hepatocytes in E12.5 and E17.5 mice and cDNAs encoding a membrane protein were selected. Northern blot analysis was employed to confirm the genes upregulated during maturation of fetal hepatocytes and neuritin, a GPI-anchored protein, was found as a membrane protein expressed in hepatocytes, but not in nonparenchymal cells. Its expression increased along with liver development and the maximum expression was achieved from the neonatal to adult stage. The neuritin protein was localized in sinusoidal lumen of hepatocytes in adult liver. Partial hepatectomy transiently downregulated the expression of neuritin. The expression of neuritin mRNA in C/EBPalpha deficient liver was reduced to about 50% of that of wild type mice. Thus, neuritin expression is well correlated to the maturation of hepatocytes and can be a useful tool to define the differentiation stage of hepatocytes. PMID:16081067

  7. Adiponectin fine-tuning of liver regeneration dynamics revealed through cellular network modelling.

    PubMed

    Correnti, Jason M; Cook, Daniel; Aksamitiene, Edita; Swarup, Aditi; Ogunnaike, Babatunde; Vadigepalli, Rajanikanth; Hoek, Jan B

    2015-01-15

    Following partial hepatectomy, the liver initiates a regenerative programme involving hepatocyte priming and replication driven by the coordinated actions of cytokine and growth factors. We investigated the mechanisms underlying adiponectin's (Adn) regulation of liver regeneration through modulation of these mediators. Adn(-/-) mice showed delayed onset of hepatocyte replication, but accelerated cell cycle progression relative to wild-type mice, suggesting Adn has multiple effects fine-tuning the kinetics of liver regeneration. We developed a computational model describing the molecular and physiological kinetics of liver regeneration in Adn(-/-) mice. We employed this computational model to evaluate the underlying regulatory mechanisms. Our analysis predicted that Adn is required for an efficient early cytokine response to partial hepatectomy, but is inhibitory to later growth factor actions. Consistent with this prediction, Adn knockout reduced hepatocyte responses to interleukin-6 during the priming phase, but enhanced growth factor levels through peak hepatocyte replication. By contrast, supraphysiological concentrations of Adn resulting from rosiglitazone treatment suppressed regeneration by reducing growth factor levels during S phase, consistent with computational predictions. Together, these results revealed that Adn fine-tunes the progression of liver regeneration through dynamically modulating molecular mediator networks and cellular interactions within the liver.

  8. Adiponectin fine-tuning of liver regeneration dynamics revealed through cellular network modeling.

    PubMed

    Correnti, Jason M; Cook, Daniel; Aksamitiene, Edita; Swarup, Aditi; Ogunnaike, Babatunde; Vadigepalli, Rajanikanth; Hoek, Jan B

    2014-11-10

    Following partial hepatectomy, the liver initiates a regenerative program involving hepatocyte priming and replication driven by coordinated cytokine and growth factor actions. We investigated the mechanisms underlying Adiponectin's (Adn) regulation of liver regeneration through modulation of these mediators. Adn-/- mice showed delayed onset of hepatocyte replication, but accelerated cell cycle progression relative to wild-type mice, suggesting Adn has multiple effects fine-tuning the kinetics of liver regeneration. We developed a computational model describing the molecular and physiological kinetics of liver regeneration in Adn-/- mice. We employed this computational model to evaluate the underlying regulatory mechanisms. Our analysis predicted that Adn is required for an efficient early cytokine response to partial hepatectomy, but is inhibitory to later growth factor actions. Consistent with this prediction, Adn knockout reduced hepatocyte responses to IL-6 during the priming phase, but enhanced growth factor levels through peak hepatocyte replication. By contrast, supraphysiological concentrations of Adn resulting from rosiglitazone treatment suppressed regeneration by reducing growth factor levels during S phase, consistent with computational predictions. Together, these results revealed that Adn fine-tunes the progression of liver regeneration through dynamically modulating molecular mediator networks and cellular interactions within the liver. This article is protected by copyright. All rights reserved.

  9. The lure of zebrafish in liver research: regulation of hepatic growth in development and regeneration.

    PubMed

    Cox, Andrew G; Goessling, Wolfram

    2015-06-01

    The liver is an essential organ that plays a pivotal role in metabolism, digestion and nutrient storage. Major efforts have been made to develop zebrafish (Danio rerio) as a model system to study the pathways regulating hepatic growth during liver development and regeneration. Zebrafish offer unique advantages over other vertebrates including in vivo imaging at cellular resolution and the capacity for large-scale chemical and genetic screens. Here, we review the cellular and molecular mechanisms that regulate hepatic growth during liver development in zebrafish. We also highlight emerging evidence that developmental pathways are reactivated following liver injury to facilitate regeneration. Finally, we discuss how zebrafish have transformed drug discovery efforts and enabled the identification of drugs that stimulate hepatic growth and provide hepatoprotection in pre-clinical models of liver injury, with the ultimate goal of identifying novel therapeutic approaches to treat liver disease.

  10. Stem/progenitor cells in liver development, homeostasis, regeneration, and reprogramming.

    PubMed

    Miyajima, Atsushi; Tanaka, Minoru; Itoh, Tohru

    2014-05-01

    The liver is a central organ for homeostasis with unique regenerative capacities. Mature hepatocytes possess a remarkable capacity to proliferate upon injury, challenging efforts to discern the role of adult liver stem cells in this process. In contrast, stem/progenitor cells in the developing liver have been extensively characterized, and these investigations have informed efforts to produce functional hepatocytes in vitro for cell therapy and drug screening. In this Review, we describe recent advances in the characterization of liver stem cells and discuss evidence supporting and refuting whether self-renewable and bipotential liver stem cells exist in development, homeostasis, regeneration, and disease.

  11. Up-regulated extracellular matrix components and inflammatory chemokines may impair the regeneration of cholestatic liver

    PubMed Central

    Zhang, Shuai; Li, Tao-Sheng; Soyama, Akihiko; Tanaka, Takayuki; Yan, Chen; Sakai, Yusuke; Hidaka, Masaaki; Kinoshita, Ayaka; Natsuda, Koji; Fujii, Mio; Kugiyama, Tota; Baimakhanov, Zhassulan; Kuroki, Tamotsu; Gu, Weili; Eguchi, Susumu

    2016-01-01

    Although the healthy liver is known to have high regenerative potential, poor liver regeneration under pathological conditions remains a substantial problem. We investigated the key molecules that impair the regeneration of cholestatic liver. C57BL/6 mice were randomly subjected to partial hepatectomy and bile duct ligation (PH+BDL group, n = 16), partial hepatectomy only (PH group, n = 16), or sham operation (Sham group, n = 16). The liver sizes and histological findings were similar in the PH and sham groups 14 days after operation. However, compared with those in the sham group, the livers in mice in the PH+BDL group had a smaller size, a lower cell proliferative activity, and more fibrotic tissue 14 days after the operation, suggesting the insufficient regeneration of the cholestatic liver. Pathway-focused array analysis showed that many genes were up- or down-regulated over 1.5-fold in both PH+BDL and PH groups at 1, 3, 7, and 14 days after treatment. Interestingly, more genes that were functionally related to the extracellular matrix and inflammatory chemokines were found in the PH+BDL group than in the PH group at 7 and 14 days after treatment. Our data suggest that up-regulated extracellular matrix components and inflammatory chemokines may impair the regeneration of cholestatic liver. PMID:27226149

  12. Up-regulated extracellular matrix components and inflammatory chemokines may impair the regeneration of cholestatic liver.

    PubMed

    Zhang, Shuai; Li, Tao-Sheng; Soyama, Akihiko; Tanaka, Takayuki; Yan, Chen; Sakai, Yusuke; Hidaka, Masaaki; Kinoshita, Ayaka; Natsuda, Koji; Fujii, Mio; Kugiyama, Tota; Baimakhanov, Zhassulan; Kuroki, Tamotsu; Gu, Weili; Eguchi, Susumu

    2016-01-01

    Although the healthy liver is known to have high regenerative potential, poor liver regeneration under pathological conditions remains a substantial problem. We investigated the key molecules that impair the regeneration of cholestatic liver. C57BL/6 mice were randomly subjected to partial hepatectomy and bile duct ligation (PH+BDL group, n = 16), partial hepatectomy only (PH group, n = 16), or sham operation (Sham group, n = 16). The liver sizes and histological findings were similar in the PH and sham groups 14 days after operation. However, compared with those in the sham group, the livers in mice in the PH+BDL group had a smaller size, a lower cell proliferative activity, and more fibrotic tissue 14 days after the operation, suggesting the insufficient regeneration of the cholestatic liver. Pathway-focused array analysis showed that many genes were up- or down-regulated over 1.5-fold in both PH+BDL and PH groups at 1, 3, 7, and 14 days after treatment. Interestingly, more genes that were functionally related to the extracellular matrix and inflammatory chemokines were found in the PH+BDL group than in the PH group at 7 and 14 days after treatment. Our data suggest that up-regulated extracellular matrix components and inflammatory chemokines may impair the regeneration of cholestatic liver. PMID:27226149

  13. Up-regulated extracellular matrix components and inflammatory chemokines may impair the regeneration of cholestatic liver.

    PubMed

    Zhang, Shuai; Li, Tao-Sheng; Soyama, Akihiko; Tanaka, Takayuki; Yan, Chen; Sakai, Yusuke; Hidaka, Masaaki; Kinoshita, Ayaka; Natsuda, Koji; Fujii, Mio; Kugiyama, Tota; Baimakhanov, Zhassulan; Kuroki, Tamotsu; Gu, Weili; Eguchi, Susumu

    2016-01-01

    Although the healthy liver is known to have high regenerative potential, poor liver regeneration under pathological conditions remains a substantial problem. We investigated the key molecules that impair the regeneration of cholestatic liver. C57BL/6 mice were randomly subjected to partial hepatectomy and bile duct ligation (PH+BDL group, n = 16), partial hepatectomy only (PH group, n = 16), or sham operation (Sham group, n = 16). The liver sizes and histological findings were similar in the PH and sham groups 14 days after operation. However, compared with those in the sham group, the livers in mice in the PH+BDL group had a smaller size, a lower cell proliferative activity, and more fibrotic tissue 14 days after the operation, suggesting the insufficient regeneration of the cholestatic liver. Pathway-focused array analysis showed that many genes were up- or down-regulated over 1.5-fold in both PH+BDL and PH groups at 1, 3, 7, and 14 days after treatment. Interestingly, more genes that were functionally related to the extracellular matrix and inflammatory chemokines were found in the PH+BDL group than in the PH group at 7 and 14 days after treatment. Our data suggest that up-regulated extracellular matrix components and inflammatory chemokines may impair the regeneration of cholestatic liver.

  14. Effects of gamma-irradiation on biosynthesis of different types of ribonucleic acids in normal and regenerating rat liver.

    PubMed Central

    Markov, G G; Dessev, G N; Russev, G C; Tsanev, R G

    1975-01-01

    1. The effect of gamma-irradiation (4000rd) on the synthesis of ribosomal (pre-rRNA) and heterogeneous nuclear RNA (pre-mRNA) in normal and in regenerating rat liver was studied by using 40 min labelling with [6(-14)C]orotic acid. 2. Partial hepatectomy caused a sharp transient increase in the specific radioactivity of the endogenous low-molecular-weight RNA precursors in the livers of both normal and irradiated rats. Irradiation of intact animals did not affect the pool. 3. Irradiation enhanced the synthesis of pre-rRNA for at least 12h. The synthesis of pre-mRNA was also enhanced, but only in the first 3h after irradiation. 4. Partial hepatectomy strongly stimulated the synthesis of both pre-rRNA and pre-mRNA. 5. The synthesis of pre-rRNA was enhanced also in regenerating liver of animals irradiated before or after the operation. The conclusion can be drawn that the early increase in the synthesis of ribosomal RNA is a non-specific cellular response to different injuring factors. 6. The only case where irradiation caused an early inhibition of RNA synthesis was that of pre-mRNA in regenerating liver. This supports the hypothesis that ionizing radiation does not suppress the transcription per se but affects the mechanisms of activation of new genes (cellular programming). PMID:1147904

  15. Global gene expression profile of normal and regenerating liver in young and old mice.

    PubMed

    Pibiri, Monica; Sulas, Pia; Leoni, Vera Piera; Perra, Andrea; Kowalik, Marta Anna; Cordella, Angela; Saggese, Pasquale; Nassa, Giovanni; Ravo, Maria

    2015-06-01

    The ability of the liver to regenerate and adjust its size after two/third partial hepatectomy (PH) is impaired in old rodents and humans. Here, we investigated by microarray analysis the expression pattern of hepatic genes in young and old untreated mice and the differences in gene expression profile following PH. Of the 10,237 messenger RNAs that had detectable expression, only 108 displayed a greater than 2-fold modification in gene expression levels between the two groups. These genes were involved in inflammatory and immune response, xenobiotics, and lipid and glucose metabolism. To identify the genes responsible for the different regenerative response, 10-week and 18-month-old mice subjected to PH were sacrificed at different time intervals after surgery. The results showed that 2463 transcripts had significantly different expression post PH between the two groups. However, in spite of impaired liver regeneration in old mice, cell cycle genes were similarly modified in both groups, the only exception being cyclin D1 gene which was up-regulated soon after PH in young mice, but mostly down-regulated in aged animals. Surprisingly, while in young hepatectomized mice, Yap messenger RNA (mRNA) expression was not significantly enhanced and protein expression essentially reflected the progression into cell cycle, its mRNA and protein levels were robustly increased in the liver of aged animals. Furthermore, a significant change of the age-related expression of the size regulator Yes-associated protein (YAP) was observed. Unexpectedly, while in young hepatectomized mice, Yap mRNA expression was not significantly enhanced and protein expression essentially reflected the progression into cell cycle, its mRNA and protein levels were robustly increased in the liver of aged animals. Moreover, when PH was performed on mitogen-induced enlarged livers, the earlier restoration of the original liver mass compared to animals subjected to PH only led to YAP down

  16. Global gene expression profile of normal and regenerating liver in young and old mice.

    PubMed

    Pibiri, Monica; Sulas, Pia; Leoni, Vera Piera; Perra, Andrea; Kowalik, Marta Anna; Cordella, Angela; Saggese, Pasquale; Nassa, Giovanni; Ravo, Maria

    2015-06-01

    The ability of the liver to regenerate and adjust its size after two/third partial hepatectomy (PH) is impaired in old rodents and humans. Here, we investigated by microarray analysis the expression pattern of hepatic genes in young and old untreated mice and the differences in gene expression profile following PH. Of the 10,237 messenger RNAs that had detectable expression, only 108 displayed a greater than 2-fold modification in gene expression levels between the two groups. These genes were involved in inflammatory and immune response, xenobiotics, and lipid and glucose metabolism. To identify the genes responsible for the different regenerative response, 10-week and 18-month-old mice subjected to PH were sacrificed at different time intervals after surgery. The results showed that 2463 transcripts had significantly different expression post PH between the two groups. However, in spite of impaired liver regeneration in old mice, cell cycle genes were similarly modified in both groups, the only exception being cyclin D1 gene which was up-regulated soon after PH in young mice, but mostly down-regulated in aged animals. Surprisingly, while in young hepatectomized mice, Yap messenger RNA (mRNA) expression was not significantly enhanced and protein expression essentially reflected the progression into cell cycle, its mRNA and protein levels were robustly increased in the liver of aged animals. Furthermore, a significant change of the age-related expression of the size regulator Yes-associated protein (YAP) was observed. Unexpectedly, while in young hepatectomized mice, Yap mRNA expression was not significantly enhanced and protein expression essentially reflected the progression into cell cycle, its mRNA and protein levels were robustly increased in the liver of aged animals. Moreover, when PH was performed on mitogen-induced enlarged livers, the earlier restoration of the original liver mass compared to animals subjected to PH only led to YAP down

  17. Characteristics of intracellular Ca2+ signals consisting of two successive peaks in hepatocytes during liver regeneration after 70% partial hepatectomy in rats

    PubMed Central

    Taira, Zenei; Ueda, Yukari; Monmasu, Hiroshi; Yamase, Daisuke; Miyake, Sayaka; Shiraishi, Maya

    2016-01-01

    Two specific signals for regulating liver regeneration were found after 70% partial hepatectomy (PH) in rats. The first finding was a sustained increasing signal of intracellular Ca2+ ([Ca2+]i) in hepatocytes, consisting of two successive peaks with the first narrow peak at 1 hour and the second broad peak increasing by day 3 and then returning to normal by day 4. The second finding was an abnormal peak in the restoring ratio (Rr) curve of liver regeneration after 70% PH at day 4, where the Rr exceeded 100% temporarily, returned to a lower level, and then proceeded to a termination phase of liver regeneration. For 4 days around the two successive [Ca2+]i peaks and abnormal peak, various physiological activities were induced to promote liver regeneration after 70% PH. mRNA expression of genes encoding Ca2+-binding proteins S100A4 and calpain was induced between the two Ca2+ peaks. Hepatocytes underwent synchronous cell proliferation as the liver was restored from 30% to 70% at day 4, and significant expression of VEGF mRNA at around day 4 promoted angiogenesis to remodel the sinusoidal system. Cytochrome P450 activity levels in microsomes and alanine aminotransferase values at 24 hours after CCl4 administration were decreased after 70% PH, which recovered transiently to the control level at day 4, returned to the decreased level, and then slowly recovered by day 10. Thus, these results indicate that day 4 is important during liver regeneration after 70% PH. PMID:27757054

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

    PubMed

    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

  19. Regulation of microRNAs and their role in liver development, regeneration and disease.

    PubMed

    Finch, Megan L; Marquardt, Jens U; Yeoh, George C; Callus, Bernard A

    2014-09-01

    Since their discovery more than a decade ago microRNAs have been demonstrated to have profound effects on almost every aspect of biology. Numerous studies in recent years have shown that microRNAs have important roles in development and in the etiology and progression of disease. This review is focused on microRNAs and the roles they play in liver development, regeneration and liver disease; particularly chronic liver diseases such as alcoholic liver disease, non-alcoholic fatty liver disease, non-alcoholic steatohepatitis, viral hepatitis and primary liver cancer. The key microRNAs identified in liver development and chronic liver disease will be discussed together with, where possible, the target messenger RNAs that these microRNAs regulate to profoundly alter these processes. This article is part of a Directed Issue entitled: The Non-coding RNA Revolution.

  20. Expression, purification and bioactivity of human augmenter of liver regeneration

    PubMed Central

    Zhang, Yang-De; Zhou, Jian; Zhao, Jin-Feng; Peng, Jian; Liu, Xiao-Dong; Liu, Xin-Sheng; Jia, Ze-Ming

    2006-01-01

    AIM: To construct the expression vectors for prokaryotic and eukaryotic human augmenter of liver regeneration (hALR) and to study their biological activity. METHODS: hALRcDNA clone was obtained from plasmid pGEM-T-hALR, and cDNA was subcloned into the prokatyotic expression vector pGEX-4T-2. The recombinant vector and pGEX-4T-2hALR were identified by enzyme digestion and DNA sequencing and transformed into E coli JM109. The positively selected clone was induced by the expression of GST-hALR fusion protein with IPTG, then the fusion protein was purified by glutathine s-transferase (GST) sepharose 4B affinity chromatography, cleaved by thrombin and the hALR monomer was obtained and detected by measuring H thymidine incorporation. RESULTS: The product of PCR from plasmid pGEM-T-hALR was examined by 1.5% sepharose electrophoresis. The specific strap was coincident with the theoretical one. The sequence was accurate and pGEX-4T-hALP digested by enzymes was coincident with the theoretical one. The sequence was accurate and the fragment was inserted in the positive direction. The recombinant vector was transformed into E coli JM109. SDS-PAGE proved that the induced expressive fusion protein showed a single band with a molecular weight of 41 kDa. The product was purified and cleaved. The molecular weights of GST and hALR were 26 kDa, 15 kDa respectively. The recombinant fusion protein accounted for 31% of the total soluble protein of bacterial lysate. HALR added to the culture medium of adult rat hepatocytes in primary culture and HepG2 cell line could significantly enhance the rate of DNA synthesis compared to the relevant control groups (P < 0.01). CONCLUSION: Purified hALR has the ability to stimulate DNA synthesis of adult rat hepatocytes in primary culture and HepG2 cells in vitro, and can provide evidence for its clinical application. PMID:16865786

  1. Forced expression of fibroblast growth factor 21 reverses the sustained impairment of liver regeneration in hPPARα(PAC) mice due to dysregulated bile acid synthesis.

    PubMed

    Liu, Hui-Xin; Hu, Ying; French, Samuel W; Gonzalez, Frank J; Wan, Yu-Jui Yvonne

    2015-01-01

    Peroxisome proliferator activated receptor α (PPARα) stimulates hepatocellular proliferation is species-specific. Activation of mouse, but not human, PPARα induces hepatocellular proliferation, hepatomegaly, and liver cancer. Here we tested the hypothesis that human and mouse PPARα affects liver regeneration differentially. PPARα-humanized mice (hPPARα(PAC)) were similar to wild type mice in responding to fasting-induced PPARα signaling. However, these mouse livers failed to regenerate in response to partial hepatectomy (PH). The liver-to-body weight ratios did not recover even 3 months after PH in hPPARα(PAC). The mouse PPARα-mediated down-regulation of let-7c was absent in hPPARα(PAC), which might partially be responsible for impaired proliferation. After PH, hPPARα(PAC) displayed steatosis, necrosis, and inflammation mainly in periportal zone 1, which suggested bile-induced toxicity. Quantification of hepatic bile acids (BA) revealed BA overload with increased hydrophobic BA in hPPARα(PAC). Forced FGF21 expression in partial hepatectomized hPPARα(PAC) reduced hepatic steatosis, prevented focal necrosis, and restored liver mass. Compared to mouse PPARα, human PPARα has a reduced capacity to regulate metabolic pathways required for liver regeneration. In addition, FGF21 can compensate for the reduced ability of human PPARα in stimulating liver regeneration, which suggests the potential application of FGF21 in promoting hepatic growth in injured and steatotic livers in humans.

  2. Self-assembling functionalized nanopeptides for immediate hemostasis and accelerative liver tissue regeneration

    NASA Astrophysics Data System (ADS)

    Cheng, Tzu-Yun; Wu, Hsi-Chin; Huang, Ming-Yuan; Chang, Wen-Han; Lee, Chao-Hsiung; Wang, Tzu-Wei

    2013-03-01

    Traumatic injury or surgery may trigger extensive bleeding. However, conventional hemostatic methods have limited efficacy and may cause surrounding tissue damage. In this study, we use self-assembling peptides (SAPs) and specifically extend fragments of functional motifs derived from fibronectin and laminin to evaluate the capability of these functionalized SAPs in the effect of hemostasis and liver tissue regeneration. From the results, these peptides can self-assemble into nanofibrous network structure and gelate into hydrogel with pH adjustment. In animal studies, the efficacy of hemostasis is achieved immediately within seconds in a rat liver model. The histological analyses by hematoxylin-eosin stain and immunohistochemistry reveal that SAPs with these functionalized motifs significantly enhance liver tissue regeneration. In brief, these SAPs may have potential as pharmacological tools to extensively advance clinical therapeutic applications in hemostasis and tissue regeneration in the field of regenerative medicine.Traumatic injury or surgery may trigger extensive bleeding. However, conventional hemostatic methods have limited efficacy and may cause surrounding tissue damage. In this study, we use self-assembling peptides (SAPs) and specifically extend fragments of functional motifs derived from fibronectin and laminin to evaluate the capability of these functionalized SAPs in the effect of hemostasis and liver tissue regeneration. From the results, these peptides can self-assemble into nanofibrous network structure and gelate into hydrogel with pH adjustment. In animal studies, the efficacy of hemostasis is achieved immediately within seconds in a rat liver model. The histological analyses by hematoxylin-eosin stain and immunohistochemistry reveal that SAPs with these functionalized motifs significantly enhance liver tissue regeneration. In brief, these SAPs may have potential as pharmacological tools to extensively advance clinical therapeutic applications

  3. Inducing and characterizing liver regeneration in mice: Reliable models, essential “readouts” and critical perspectives

    PubMed Central

    Mastellos, Dimitrios C.; DeAngelis, Robert A.; Lambris, John D.

    2013-01-01

    Elucidating the molecular circuitry that regulates regenerative responses in mammals has recently attracted considerable attention because of its emerging impact on modern bioengineering, tissue replacement technologies, and organ transplantation. The liver is one of the few organs of the adult body that exhibitsa prominent regenerative capacity in response to toxic injury, viral infection, or surgical resection. Over the years, mechanistic insights into the liver’s regenerative potential have been provided by rodent models of chemical liver injury or surgical resection that faithfully recapitulate hallmarks of human pathophysiology and trigger robust hepatocyte proliferation leading to organ restoration. The advent of mouse transgenics has undeniably catalyzed the wider application of such models for researching liver pathobiology. This article provides a comprehensive overview of the most reliable and widely applied murine models of liver regeneration and also discusses helpful hints, considerations, and limitations related to the use of these models in liver regeneration studies. PMID:24416636

  4. CXC chemokine signaling in the liver: Impact on repair and regeneration

    PubMed Central

    Van Sweringen, Heather L.; Sakai, Nozomu; Tevar, Amit D.; Burns, Justin M.; Edwards, Michael J.; Lentsch, Alex B.

    2011-01-01

    The process of liver repair and regeneration following hepatic injury is complex and relies on a temporally coordinated integration of several key signaling pathways. Pathways activated by members of the CXC family of chemokines play important roles in the mechanisms of liver repair and regeneration through their effects on hepatocytes. However, little is known about the signaling pathways utilized by CXC chemokine receptors in hepatocytes. Here we review our current understanding of the pathways involved in both CXC chemokine receptor signaling in other cell types, most notably neutrophils, and similar pathways operant during hepatocyte proliferation/liver regeneration in order to formulate a basis for the function of CXC chemokine receptor signaling in hepatocytes. PMID:21626524

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

    SciTech Connect

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

    2011-04-01

    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

  6. Hepatic non-parenchymal cells and extracellular matrix participate in oval cell-mediated liver regeneration

    PubMed Central

    Zhang, Wei; Chen, Xiao-Ping; Zhang, Wan-Guang; Zhang, Feng; Xiang, Shuai; Dong, Han-Hua; Zhang, Lei

    2009-01-01

    AIM: To elucidate the interaction between non-parenchymal cells, extracellular matrix and oval cells during the restituting process of liver injury induced by partial hepatectomy (PH). METHODS: We examined the localization of oval cells, non-parenchymal cells, and the extracellular matrix components using immunohistochemical and double immunofluorescent analysis during the proliferation and differentiation of oval cells in N-2-acetylaminofluorene (2-AAF)/PH rat model. RESULTS: By day 2 after PH, small oval cells began to proliferate around the portal area. Most of stellate cells and laminin were present along the hepatic sinusoids in the periportal area. Kupffer cells and fibronectin markedly increased in the whole hepatic lobule. From day 4 to 9, oval cells spread further into hepatic parenchyma, closely associated with stellate cells, fibronectin and laminin. Kupffer cells admixed with oval cells by day 6 and then decreased in the periportal zone. From day 12 to 15, most of hepatic stellate cells (HSCs), laminin and fibronectin located around the small hepatocyte nodus, and minority of them appeared in the nodus. Kupffer cells were mainly limited in the pericentral sinusoids. After day 18, the normal liver lobule structures began to recover. CONCLUSION: Local hepatic microenvironment may participate in the oval cell-mediated liver regeneration through the cell-cell and cell-matrix interactions. PMID:19195056

  7. BETA-CATENIN SIGNALING, LIVER REGENERATION AND HEPATOCELLULAR CANCER: SORTING THE GOOD FROM THE BAD

    PubMed Central

    Nejak-Bowen, Kari Nichole; Monga, Satdarshan P. S.

    2011-01-01

    Among the adult organs, liver is unique for its ability to regenerate. A concerted signaling cascade enables optimum initiation of the regeneration process following insults brought about by surgery or a toxicant. Additionally, there exists a cellular redundancy, whereby a transiently amplifying progenitor population appears and expands to ensure regeneration, when differentiated cells of the liver are unable to proliferate in both experimental and clinical scenarios. One such pathway of relevance in these phenomena is Wnt/β-catenin signaling, which is activated relatively early during regeneration mostly through post-translational modifications. Once activated, β-catenin signaling drives the expression of target genes that are critical for cell cycle progression and contribute to initiation of the regeneration process. The role and regulation of Wnt/β-catenin signaling is now documented in rats, mice, zebrafish and patients. More recently, a regenerative advantage of the livers in β-catenin overexpressing mice was reported, as was also the case after exogenous Wnt-1 delivery to the liver paving the way for assessing means to stimulate the pathway for therapeutics in liver failure. β-Catenin is also pertinent in hepatic oval cell activation and differentiation. However, aberrant activation of the Wnt/β-catenin signaling is reported in a significant subset of hepatocellular cancers (HCC). While many mechanisms of such activation have been reported, the most functional means of aberrant and sustained activation is through mutations in the β-catenin gene or in AXIN1/2, which encodes for a scaffolding protein critical for β-catenin degradation. Intriguingly, in experimental models hepatic overexpression of normal or mutant β-catenin is insufficient for tumorigenesis. In fact β-catenin loss promoted chemical carcinogenesis in the liver due to alternate mechanisms. Since most HCC occur in the backdrop of chronic hepatic injury, where hepatic regeneration is

  8. Longitudinal in-vivo volumetry study for porcine liver regeneration from CT data.

    PubMed

    Zhou, Jiayin; Huang, Weimin; Chang, Stephen K Y; Xiong, Wei; Oo, Thiha; Chen, Wenyu

    2014-01-01

    The use of hepatic-like cloned cord lining epithelial cells (CLEC) to enhance liver regeneration has been proposed, but has not been properly investigated in a large animal study. The paper presents a system developed for the longitudinal in-vivo volumetry study on porcine liver regeneration from computed tomography (CT) data. In this system, a rough 3D liver volume is firstly automatically segmented by a 3D mesh deformation-based method. Then a refinement step to eliminate the segmentation error is carried out by a 3D post-editing tool, followed by mesh-volume conversion and volume calculation. This system was applied in a pilot study, which was composed of 4/4 pigs in the Experimental/Control Groups, to measure liver volumes over pre- to post-operative time course. Experimental results suggest that (1) the developed system can perform CT-based porcine liver volumetry efficiently, and (2) the infusion of CLEC to liver remnant may potentially enhance the liver regeneration. PMID:25571052

  9. Loss of α1,6-fucosyltransferase suppressed liver regeneration: implication of core fucose in the regulation of growth factor receptor-mediated cellular signaling.

    PubMed

    Wang, Yuqin; Fukuda, Tomohiko; Isaji, Tomoya; Lu, Jishun; Gu, Wei; Lee, Ho-Hsun; Ohkubo, Yasuhito; Kamada, Yoshihiro; Taniguchi, Naoyuki; Miyoshi, Eiji; Gu, Jianguo

    2015-02-05

    Core fucosylation is an important post-translational modification, which is catalyzed by α1,6-fucosyltransferase (Fut8). Increased expression of Fut8 has been shown in diverse carcinomas including hepatocarcinoma. In this study, we investigated the role of Fut8 expression in liver regeneration by using the 70% partial hepatectomy (PH) model, and found that Fut8 is also critical for the regeneration of liver. Interestingly, we show that the Fut8 activities were significantly increased in the beginning of PH (~4d), but returned to the basal level in the late stage of PH. Lacking Fut8 led to delayed liver recovery in mice. This retardation mainly resulted from suppressed hepatocyte proliferation, as supported not only by a decreased phosphorylation level of epidermal growth factor (EGF) receptor and hepatocyte growth factor (HGF) receptor in the liver of Fut8(-/-) mice in vivo, but by the reduced response to exogenous EGF and HGF of the primary hepatocytes isolated from the Fut8(-/-) mice. Furthermore, an administration of L-fucose, which can increase GDP-fucose synthesis through a salvage pathway, significantly rescued the delayed liver regeneration of Fut8(+/-) mice. Overall, our study provides the first direct evidence for the involvement of Fut8 in liver regeneration.

  10. In vivo liver regeneration potential of human induced pluripotent stem cells from diverse origins.

    PubMed

    Liu, Hua; Kim, Yonghak; Sharkis, Saul; Marchionni, Luigi; Jang, Yoon-Young

    2011-05-11

    Human induced pluripotent stem cells (iPSCs) are a potential source of hepatocytes for liver transplantation to treat end-stage liver disease. In vitro differentiation of human iPSCs into hepatic cells has been achieved using a multistage differentiation protocol, but whether these cells are functional and capable of engrafting and regenerating diseased liver tissue is not clear. We show that human iPSC-derived hepatic cells at various differentiation stages can engraft the liver in a mouse transplantation model. Using the same differentiation and transplantation protocols, we also assessed the ability of human iPSCs derived from each of the three developmental germ layer tissues (that is, ectoderm, mesoderm, and endoderm) to regenerate mouse liver. These iPSC lines, with similar but distinct global DNA methylation patterns, differentiated into multistage hepatic cells with an efficiency similar to that of human embryonic stem cells. Human hepatic cells at various differentiation stages derived from iPSC lines of different origins successfully repopulated the liver tissue of mice with liver cirrhosis. They also secreted human-specific liver proteins into mouse blood at concentrations comparable to that of proteins secreted by human primary hepatocytes. Our results demonstrate the engraftment and liver regenerative capabilities of human iPSC-derived multistage hepatic cells in vivo and suggest that human iPSCs of distinct origins and regardless of their parental epigenetic memory can efficiently differentiate along the hepatic lineage.

  11. Regulated Catalysis of Extracellular Nucleotides by Vascular CD39/ENTPD1 Is Required for Liver Regeneration

    PubMed Central

    BELDI, GUIDO; WU, YAN; SUN, XIAOFENG; IMAI, MASATO; ENJYOJI, KEIICHI; CSIZMADIA, EVA; CANDINAS, DANIEL; ERB, LAURIE; ROBSON, SIMON C.

    2010-01-01

    Background & Aims Little is known about how endothelial cells respond to injury, regulate hepatocyte turnover and reconstitute the hepatic vasculature. We aimed to determine the effects of the vascular ectonucleotidase CD39 on sinusoidal endothelial cell responses following partial hepatectomy and to dissect purinergic and growth factor interactions in this model. Methods Parameters of liver injury and regeneration, as well as the kinetics of hepatocellular and sinusoidal endothelial cell proliferation, were assessed following partial hepatectomy in mice that do not express CD39, that do not express ATP/UTP receptor P2Y2, and in controls. The effects of extracellular ATP on vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), and interleukin-6 responses were determined in vivo and in vitro. Phosphorylation of the endothelial VEGF receptor in response to extracellular nucleotides and growth factors was assessed in vitro. Results After partial hepatectomy, expression of the vascular ectonucleotidase CD39 increased on sinusoidal endothelial cells. Targeted disruption of CD39 impaired hepatocellular regeneration, reduced angiogenesis, and increased hepatic injury, resulting in pronounced vascular endothelial apoptosis, and decreased survival. Decreased HGF release by sinusoidal endothelial cells, despite high levels of VEGF, reduced paracrine stimulation of hepatocytes. Failure of VEGF receptor-2/KDR transactivation by extracellular nucleotides on CD39-null endothelial cells was associated with P2Y2 receptor desensitization. Conclusions Regulated phosphohydrolysis of extracellular nucleotides by CD39 coordinates both hepatocyte and endothelial cell proliferation following partial hepatectomy. Lack of CD39 activity is associated with decreased hepatic regeneration and failure of vascular reconstitution. PMID:18804472

  12. Prolactin promotes normal liver growth, survival, and regeneration in rodents: effects on hepatic IL-6, suppressor of cytokine signaling-3, and angiogenesis.

    PubMed

    Moreno-Carranza, Bibiana; Goya-Arce, Maite; Vega, Claudia; Adán, Norma; Triebel, Jakob; López-Barrera, Fernando; Quintanar-Stéphano, Andrés; Binart, Nadine; Martínez de la Escalera, Gonzalo; Clapp, Carmen

    2013-10-01

    Prolactin (PRL) is a potent liver mitogen and proangiogenic hormone. Here, we used hyperprolactinemic rats and PRL receptor-null mice (PRLR(-/-)) to study the effect of PRL on liver growth and angiogenesis before and after partial hepatectomy (PH). Liver-to-body weight ratio (LBW), hepatocyte and sinusoidal endothelial cell (SEC) proliferation, and hepatic expression of VEGF were measured before and after PH in hyperprolactinemic rats, generated by placing two anterior pituitary glands (AP) under the kidney capsule. Also, LBW and hepatic expression of IL-6, as well as suppressor of cytokine signaling-3 (SOCS-3), were evaluated in wild-type and PRLR(-/-) mice before and after PH. Hyperprolactinemia increased the LBW, the proliferation of hepatocytes and SECs, and VEGF hepatic expression. Also, liver regeneration was increased in AP-grafted rats and was accompanied by elevated hepatocyte and SEC proliferation, and VEGF expression compared with nongrafted controls. Lowering circulating PRL levels with CB-154, an inhibitor of AP PRL secretion, prevented AP-induced stimulation of liver growth. Relative to wild-type animals, PRLR(-/-) mice had smaller livers, and soon after PH, they displayed an approximately twofold increased mortality and elevated and reduced hepatic IL-6 and SOCS-3 expression, respectively. However, liver regeneration was improved in surviving PRLR(-/-) mice. PRL stimulates normal liver growth, promotes survival, and regulates liver regeneration by mechanisms that may include hepatic downregulation of IL-6 and upregulation of SOCS-3, increased hepatocyte proliferation, and angiogenesis. PRL contributes to physiological liver growth and has potential clinical utility for ensuring survival and regulating liver mass in diseases, injuries, or surgery of the liver.

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

    PubMed Central

    Elswefy, Sahar E; Rashed, Laila A; Younis, Nahla N; Shaheen, Mohamed A; Ghanim, Amal MH

    2016-01-01

    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 × 106 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 < 0.001), increases in HGF and MMP-2 mRNA and downregulating CK-19 mRNA. Sliymarin, however, induced similar but less prominent effects compared to BM-MSCs. In conclusion, 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. PMID:26811102

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

    PubMed

    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 < 0.001), increases in HGF and MMP-2 mRNA and downregulating CK-19 mRNA. Sliymarin, however, induced similar but less prominent effects compared to BM-MSCs. In conclusion, 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.

  15. What is Known Regarding the Participation of Factor Nrf-2 in Liver Regeneration?

    PubMed Central

    Morales-González, José A.; Madrigal-Santillán, Eduardo; Morales-González, Ángel; Bautista, Mirandeli; Gayosso-Islas, Evila; Sánchez-Moreno, Cecilia

    2015-01-01

    It has been known for years that, after chemical damage or surgical removal of its tissue, the liver initiates a series of changes that, taken together, are known as regeneration, which are focused on the recovery of lost or affected tissue in terms of the anatomical or functional aspect. The Nuclear factor-erythroid 2-related factor (Nrf-2) is a reduction-oxidation reaction (redox)-sensitive transcriptional factor, with the basic leucine Zipper domain (bZIP) motif, encoding the NFE2L2 gene. The Keap1-Nrf2-ARE pathway is transcendental in the regulation of various cellular processes, such as antioxidant defenses, redox equilibrium, the inflammatory process, the apoptotic processes, intermediate metabolism, detoxification, and cellular proliferation. Some reports have demonstrated the regulator role of Nrf-2 in the cellular cycle of the hepatocyte, as well as in the modulation of the antioxidant response and of apoptotic processes during liver regeneration. It has been reported that there is a delay in liver regeneration after Partial hepatectomy (PH) in the absence of Nrf-2, and similarly as a regulator of hepatic cytoprotection due to diverse chemical or biological agents, and in diseases such as hepatitis, fibrosis, cirrhosis, and liver cancer. This regulator/protector capacity is due to the modulation of the Antioxidant response elements (ARE). It is postulated that oxidative stress (OS) can participate in the initial stages of liver regeneration and that Nrf-2 can probably participate. Studies are lacking on the different initiation stages, maintenance, and the termination of liver regeneration alone or with ethanol. PMID:26010752

  16. Uptake and distribution of hepatocyte growth factor in normal and regenerating adult rat liver.

    PubMed Central

    Liu, M. L.; Mars, W. M.; Zarnegar, R.; Michalopoulos, G. K.

    1994-01-01

    We have previously shown that systemically injected hepatocyte growth factor (HGF) is primarily taken up by the liver. The present study shows that HGF injected systemically or through the portal circulation is retained primarily at periportal sites. The periportal retention of HGF seems to persist longer in regenerating liver. The percentage of the total HGF injected that was retained within the liver at 1 minute after injection varied with the dose. A maximal amount of 0.157 +/- 0.012 microgram of HGF per gram liver tissue is retained by normal liver. Analysis of the circulating form of HGF in the plasma showed a relative enrichment with time for the heterodimeric form of HGF. A portion of portally injected HGF, composed of both single chain and two chain (heterodimeric) form was excreted intact in the bile. This was found in both normal and regenerating liver. These studies show that the liver can sequester large amounts of HGF and that the sequestration occurs primarily at periportal sites. Our studies support the hypothesis that a nonlysosomal processing pathway for HGF is present in the liver. Images Figure 1 Figure 3 Figure 4 Figure 6 PMID:8291602

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

    PubMed

    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.

  18. Sucrose administration to partially hepatectomized rats: a possible model to study ethanol-induced inhibition of liver regeneration.

    PubMed

    Gutiérrez-Salinas, J; Aranda-Fraustro, A; Paredes-Díaz, R; Hernández-Muñoz, R

    1996-09-01

    Although acute ethanol treatment drastically inhibits liver regeneration after partial hepatectomy, the exact mechanisms involved remain obscure. On the other hand, it is known that early carbohydrate administration promotes a more successful restoration of the liver mass. Therefore, carbohydrate administration could be an experimental approach for studying ethanol action on the regenerating liver. In rats subjected to two-thirds partial hepatectomy, ethanol was administered alone or in combination with a variety of carbohydrates (glucose, fructose, glucose plus fructose, sucrose and maltose). In liver samples, regeneration parameters and histological assessment were performed. Blood ethanol and metabolites reflecting liver function were assayed. Ethanol intake strongly decreased the incorporation of [3H]thymidine into liver DNA, the concentration of DNA/g of tissue, and thymidine kinase activity. In this group, severe alterations in cell structure (i.e. abundant fat droplets and abnormal mitochondria) were found. Carbohydrates readily improved the survival rate of ethanol-intoxicated hepatectomized rats. Sucrose was effective in reverting the ethanol-induced alterations in liver structure and the parameters of liver regeneration, and partially blocked the ethanol-induced alterations in serum levels of albumin, triacylglycerols and ammonia without modifying the blood levels and clearance of ethanol. Data suggest that the beneficial action of sucrose might be related to an adequate supply of energetic sources at early times of liver regeneration, rather than altering ethanol bioavailability. Thus, the present model could be an experimental approach for studying the metabolic alterations involved in the ethanol-induced inhibition of the liver regeneration.

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

    PubMed

    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.

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

    PubMed Central

    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. PMID:26136687

  1. Stem cells versus plasticity in liver and pancreas regeneration.

    PubMed

    Kopp, Janel L; Grompe, Markus; Sander, Maike

    2016-03-01

    Cell replacement in adult organs can be achieved through stem cell differentiation or the replication or transdifferentiation of existing cells. In the adult liver and pancreas, stem cells have been proposed to replace tissue cells, particularly following injury. Here we review how specialized cell types are produced in the adult liver and pancreas. Based on current evidence, we propose that the plasticity of differentiated cells, rather than stem cells, accounts for tissue repair in both organs.

  2. Stem cells versus plasticity in liver and pancreas regeneration.

    PubMed

    Kopp, Janel L; Grompe, Markus; Sander, Maike

    2016-03-01

    Cell replacement in adult organs can be achieved through stem cell differentiation or the replication or transdifferentiation of existing cells. In the adult liver and pancreas, stem cells have been proposed to replace tissue cells, particularly following injury. Here we review how specialized cell types are produced in the adult liver and pancreas. Based on current evidence, we propose that the plasticity of differentiated cells, rather than stem cells, accounts for tissue repair in both organs. PMID:26911907

  3. Regulation of soluble neuropilin 1, an endogenous angiogenesis inhibitor, in liver development and regeneration.

    PubMed

    Panigrahy, Dipak; Adini, Irit; Mamluk, Roni; Levonyak, Nicholas; Bruns, Christiane J; D'Amore, Patricia A; Klagsbrun, Michael; Bielenberg, Diane R

    2014-08-01

    Neuropilin-1 (NRP1) is a receptor for vascular endothelial growth factor (VEGF). A soluble isoform of Nrp1 (sNrp1) has not been described in the mouse. Our goal was to examine the expression of mouse sNrp1 during liver development and regeneration.sNrp1 was cloned from mouse liver. The expression of sNrp1 and VEGF was examined in mouse liver during post-natal development and regeneration using northern blot, western blot, in situ hybridisation, and immunohistochemical analyses. HGF/NRP1 binding was examined in vitro.A novel 588-amino acid sNrp1 isoform was found to contain the ligand binding regions of Nrp1. The adult liver expressed more sNrp1 than full-length Nrp1. In vivo, hepatocytes constitutively expressed VEGF and sNrp1 in the quiescent state. sNrp1 was highly up-regulated at P20, a time point coinciding with a plateau in liver and body weights. Following hepatectomy, endogenous levels of sNrp1 decreased during the rapid growth phase, and VEGF levels were highest just prior to and during the angiogenic phase. sNrp1 levels again rose 5-10 days post-hepatectomy, presumably to control regeneration. HGF protein bound NRP1 and binding was competed with sNRP1.We cloned a novel mouse sNrp1 isoform from liver and provide evidence that this endogenous angiogenesis inhibitor may regulate VEGF or HGF bioavailability during normal physiological growth and development as well as during liver regeneration.

  4. The role of liver progenitor cells during liver regeneration, fibrogenesis, and carcinogenesis.

    PubMed

    Köhn-Gaone, Julia; Gogoi-Tiwari, Jully; Ramm, Grant A; Olynyk, John K; Tirnitz-Parker, Janina E E

    2016-02-01

    The growing worldwide challenge of cirrhosis and hepatocellular carcinoma due to increasing prevalence of excessive alcohol consumption, viral hepatitis, obesity, and the metabolic syndrome has sparked interest in stem cell-like liver progenitor cells (LPCs) as potential candidates for cell therapy and tissue engineering, as an alternative approach to whole organ transplantation. However, LPCs always proliferate in chronic liver diseases with a predisposition to cancer; they have been suggested to play major roles in driving fibrosis, disease progression, and may even represent tumor-initiating cells. Hence, a greater understanding of the factors that govern their activation, communication with other hepatic cell types, and bipotential differentiation as opposed to their potential transformation is needed before their therapeutic potential can be harnessed.

  5. Telomerase activation in liver regeneration and hepatocarcinogenesis: Dr. Jekyll or Mr. Hyde?

    PubMed

    Wege, Henning; Brümmendorf, Tim H

    2007-01-01

    The liver has a remarkable capability to restore its functional capacity following liver injury. According to the current paradigm, differentiated and usually quiescent hepatocytes are the primary cell type responsible for liver repair. As reserve compartment, bipotent hepatic progenitor cells are activated, especially if extensive loss or damage of hepatocytes with impaired replication occurs, e.g. in cirrhotic liver tissue. Recently, animal studies have suggested that liver regeneration following partial hepatectomy is associated with telomerase activation. Telomerase, a ribonucleoprotein with reverse transcriptase activity, plays a pivotal role in maintaining telomere length and chromosomal stability in proliferating cells. In cells lacking telomerase activity, replication-associated telomere shortening limits the replicative lifespan. Therefore, in the context of liver regeneration, telomerase activation might be a cellular mechanism to confer an extended lifespan to replicating hepatocytes and hepatic progenitor cells. On the other hand, high levels of telomerase activity are a hallmark of cancer, including hepatocellular carcinoma. Moreover, recent data indicate that telomerase activation may be an early event in hepatocarcinogenesis. At present, it is unclear, whether telomerase activation preserves the non-malignant phenotype and replicative longevity of liver cells or constitutes an early alteration obligatory for an unlimited proliferation and malignant transformation. PMID:18220890

  6. WNT5A inhibits hepatocyte proliferation and concludes β-catenin signaling in liver regeneration.

    PubMed

    Yang, Jing; Cusimano, Antonella; Monga, Jappmann K; Preziosi, Morgan E; Pullara, Filippo; Calero, Guillermo; Lang, Richard; Yamaguchi, Terry P; Nejak-Bowen, Kari N; Monga, Satdarshan P

    2015-08-01

    Activation of Wnt/β-catenin signaling during liver regeneration (LR) after partial hepatectomy (PH) is observed in several species. However, how this pathway is turned off when hepatocyte proliferation is no longer required is unknown. We assessed LR in liver-specific knockouts of Wntless (Wls-LKO), a protein required for Wnt secretion from a cell. When subjected to PH, Wls-LKO showed prolongation of hepatocyte proliferation for up to 4 days compared with littermate controls. This coincided with increased β-catenin-T-cell factor 4 interaction and cyclin-D1 expression. Wls-LKO showed decreased expression and secretion of inhibitory Wnt5a during LR. Wnt5a expression increased between 24 and 48 hours, and Frizzled-2 between 24 and 72 hours, after PH in normal mice. Treatment of primary mouse hepatocytes and liver tumor cells with Wnt5a led to a notable decrease in β-catenin-T-cell factor activity, cyclin-D1 expression, and cell proliferation. Intriguingly, Wnt5a-LKO did not display any prolongation of LR because of compensation by other cells. In addition, Wnt5a-LKO hepatocytes failed to respond to exogenous Wnt5a treatment in culture because of a compensatory decrease in Frizzled-2 expression. In conclusion, we demonstrate Wnt5a to be, by default, a negative regulator of β-catenin signaling and hepatocyte proliferation, both in vitro and in vivo. We also provide evidence that the Wnt5a/Frizzled-2 axis suppresses β-catenin signaling in hepatocytes in an autocrine manner, thereby contributing to timely conclusion of the LR process.

  7. Participation of liver progenitor cells in liver regeneration: lack of evidence in the AAF/PH rat model.

    PubMed

    Dusabineza, Ange-Clarisse; Van Hul, Noémi K; Abarca-Quinones, Jorge; Starkel, Peter; Najimi, Mustapha; Leclercq, Isabelle A

    2012-01-01

    When hepatocyte proliferation is impaired, liver progenitor cells (LPC) are activated to participate in liver regeneration. We used the 2-acetaminofluorene/partial hepatectomy (AAF/PH) model to evaluate the contribution of LPC to liver cell replacement and function restoration. Fischer rats subjected to AAF/PH (or PH alone) were investigated 7, 10 and 14 days post-hepatectomy. Liver mass recovery (LMR) was estimated, and the liver mass to body weight ratio calculated. We used serum albumin and bilirubin levels, and liver albumin mRNA levels to assess the liver function. LPC expansion was analyzed by cytokeratin 19 (CK19), glutathione S-transferase protein (GSTp) immunohistochemistry and by CK19, CD133, transforming growth factor-β1 and hepatocyte growth factor mRNA expression in livers. Cell proliferation was evaluated by Ki67 and BrdU immunostaining. Compared with PH alone where LMR was ∼100% 14 days post-PH, LMR was defective in AAF/PH rats (64.1±15.5%, P=0.0004). LPC expansion was scarce in PH livers (0.5±0.4% of CK19(+) area), but significant in AAF/PH livers (8.5±7.2% of CK19(+)), and inversely correlated to LMR (r(2)=0.63, P<0.0001). A quarter of AAF/PH animals presented liver failure (low serum albumin and high serum bilirubin) 14 days post-PH. Compared with animals with preserved function, this was associated with a lower LMR (50±6.8 vs 74.6±9.4%, P=0.0005), a decreased liver to body weight ratio (2±0.3 vs 3.5±0.6%, P=0.001), and a larger LPC expansion such as proliferating Ki67(+) LPC covered 17.4±4.2% of the liver parenchyma vs 3.1±1.5%, (P<0.0001). Amongst those, rare LPC with an intermediate hepatocyte-like phenotype were seen. Also, less than 2% of hepatocytes were engaged into the cell cycle (Ki67(+)), while more numerous (∼25% of hepatocytes) in the livers with preserved function. These observations suggest that, in this model, the efficient recovery of the liver function was ensured rather by the proliferation of mature hepatocytes

  8. Sanguineous normothermic machine perfusion improves hemodynamics and biliary epithelial regeneration in DCD porcine livers

    PubMed Central

    Liu, Qiang; Nassar, Ahmed; Farias, Kevin; Buccini, Laura; Baldwin, William; Mangino, Martin; Bennett, Ana; O'Rourke, Colin; Okamoto, Toshiro; Uso, Teresa Diago; Fung, John; Abu-Elmagd, Kareem; Miller, Charles; Quintini, Cristiano

    2014-01-01

    The effect of normothermic machine perfusion (NMP) on post-reperfusion hemodynamics and extrahepatic biliary duct histology of donors after cardiac death (DCD) livers after transplantation has not been addressed thoroughly and represented the object of this study. Ten livers (n=5/group) with 60’ of warm ischemia were preserved by cold storage (CS) or sanguineous NMP for 10 hours, and then reperfused for 24 hours with whole blood in an isolated perfusion system to simulate transplantation. In our experiment, arterial and portal venous flows were stable in NMP group during the entire simulated reperfusion, while decreased dramatically in CS group after 16 hours post-reperfusion (P<.05), findings consistent with severe parenchymal injury. Similarly, significant differences existed between CS and NMP group on hepatocellular enzyme release, bile volume produced, and enzyme released into bile (P<.05). On histology CS livers presented with diffuse hepatocyte congestion, necrosis, intraparenchymal hemorrhage, denudated biliary epithelium and submucosal bile duct necrosis, while NMP liver showed very mild injury in liver parenchyma and biliary architecture. Most importantly, Ki67 staining in extrahepatic bile duct showed biliary epithelial regeneration. Our findings advance the knowledge of post-reperfusion events that characterize DCD livers and propose NMP as a beneficial preservation modality able to improve biliary regeneration after a major ischemic event, which may prevent in clinical transplantation the development of ischemic cholangiopathy. PMID:24805852

  9. Nrf2 is involved in maintaining hepatocyte identity during liver regeneration.

    PubMed

    Zou, Yuhong; Lee, Joonyong; Nambiar, Shashank Manohar; Hu, Min; Rui, Wenjuan; Bao, Qi; Chan, Jefferson Y; Dai, Guoli

    2014-01-01

    Nrf2, a central regulator of the cellular defense against oxidative stress and inflammation, participates in modulating hepatocyte proliferation during liver regeneration. It is not clear, however, whether Nrf2 regulates hepatocyte growth, an important cellular mechanism to regain the lost liver mass after partial hepatectomy (PH). To determine this, various analyses were performed in wild-type and Nrf2-null mice following PH. We found that, at 60 h post-PH, the vast majority of hepatocytes lacking Nrf2 reduced their sizes, activated hepatic progenitor markers (CD133, TWEAK receptor, and trefoil factor family 3), depleted HNF4α protein, and downregulated the expression of a group of genes critical for their functions. Thus, the identity of hepatocytes deficient in Nrf2 was transiently but massively impaired in response to liver mass loss. This event was associated with the coupling of protein depletion of hepatic HNF4α, a master regulator of hepatocyte differentiation, and concomitant inactivation of hepatic Akt1 and p70S6K, critical hepatocyte growth signaling molecules. We conclude that Nrf2 participates in maintaining newly regenerated hepatocytes in a fully differentiated state by ensuring proper regulation of HNF4α, Akt1, and p70S6K during liver regeneration.

  10. Nrf2 Is Involved in Maintaining Hepatocyte Identity during Liver Regeneration

    PubMed Central

    Zou, Yuhong; Lee, Joonyong; Nambiar, Shashank Manohar; Hu, Min; Rui, Wenjuan; Bao, Qi; Chan, Jefferson Y.; Dai, Guoli

    2014-01-01

    Nrf2, a central regulator of the cellular defense against oxidative stress and inflammation, participates in modulating hepatocyte proliferation during liver regeneration. It is not clear, however, whether Nrf2 regulates hepatocyte growth, an important cellular mechanism to regain the lost liver mass after partial hepatectomy (PH). To determine this, various analyses were performed in wild-type and Nrf2-null mice following PH. We found that, at 60 h post-PH, the vast majority of hepatocytes lacking Nrf2 reduced their sizes, activated hepatic progenitor markers (CD133, TWEAK receptor, and trefoil factor family 3), depleted HNF4α protein, and downregulated the expression of a group of genes critical for their functions. Thus, the identity of hepatocytes deficient in Nrf2 was transiently but massively impaired in response to liver mass loss. This event was associated with the coupling of protein depletion of hepatic HNF4α, a master regulator of hepatocyte differentiation, and concomitant inactivation of hepatic Akt1 and p70S6K, critical hepatocyte growth signaling molecules. We conclude that Nrf2 participates in maintaining newly regenerated hepatocytes in a fully differentiated state by ensuring proper regulation of HNF4α, Akt1, and p70S6K during liver regeneration. PMID:25222179

  11. Hepatoprotective effect of Geranium schiedeanum against ethanol toxicity during liver regeneration

    PubMed Central

    Madrigal-Santillán, Eduardo; Bautista, Mirandeli; Gayosso-De-Lucio, Juan A; Reyes-Rosales, Yadira; Posadas-Mondragón, Araceli; Morales-González, Ángel; Soriano-Ursúa, Marvin A; García-Machorro, Jazmín; Madrigal-Bujaidar, Eduardo; Álvarez-González, Isela; Morales-González, José A

    2015-01-01

    AIM: To evaluate the effect of an extract of Geranium schiedeanum (Gs) as a hepatoprotective agent against ethanol (EtOH)-induced toxicity in rats. METHODS: Male Wistar rats weighing 200-230 g were subjected to a 70% partial hepatectomy (PH); they were then divided into three groups (groups 1-3). During the experiment, animals in group 1 drank only water. The other two groups (2-3) drank an aqueous solution of EtOH (40%, v/v). Additionally, rats in group 3 received a Gs extract daily at a dose of 300 mg/kg body weight intragastically. Subsequently, to identify markers of liver damage in serum, alanine aminotransferase, aspartate aminotransferase, albumin and bilirubin were measured by colorimetric methods. Glucose, triglyceride and cholesterol concentrations were also determined. In addition, oxidative damage was estimated by measuring lipid peroxidation [using thiobarbituric-acid reactive substances (TBARS)] in both plasma and the liver and by measuring the total concentration of antioxidants in serum and the total antioxidant capacity in the liver. In addition, a liver mass gain assessment, total DNA analysis and a morpho-histological analysis of the liver from animals in all three groups were performed and compared. Finally, the number of deaths observed in the three groups was analyzed. RESULTS: Administration of the Geranium shiedeanum extract significantly reduced the unfavorable effect of ethanol on liver regeneration (restitution liver mass: PH-EtOH group 60.68% vs PH-Gs-EtOH group 69.22%). This finding was congruent with the reduced levels of hepatic enzymes and the sustained or increased levels of albumin and decreased bilirubin in serum. The extract also modified the metabolic processes that regulate glucose and lipid levels, as observed from the serum measurements. Lower antioxidant levels and the liver damage induced by EtOH administration appeared to be mitigated by the extract, as observed from the TBARs (PH-EtOH group 200.14 mmol/mg vs PH

  12. Ah Receptor–Mediated Suppression of Liver Regeneration through NC-XRE–Driven p21Cip1 Expression

    PubMed Central

    Jackson, Daniel P.; Li, Hui; Mitchell, Kristen A.; Joshi, Aditya D.

    2014-01-01

    Previous studies in hepatocyte-derived cell lines and the whole liver established that the aryl hydrocarbon receptor (AhR) can disrupt G1-phase cell cycle progression following exposure to persistent AhR agonists, such as TCDD (dioxin, 2,3,7,8-tetrachlorodibenzo-p-dioxin). Growth arrest was attributed to inhibition of G1-phase cyclin-dependent kinase 2 (CDK2) activity. The present study examined the effect of TCDD exposure on liver regeneration following 70% partial hepatectomy in mice lacking the Cip/Kip inhibitors p21Cip1 or p27Kip1 responsible for regulating CDK2 activity. Assessment of the regenerative process in wild-type, p21Cip1 knockout, and p27Kip1 knockout mice confirmed that TCDD-induced inhibition of liver regeneration is entirely dependent on p21Cip1 expression. Compared with wild-type mice, the absence of p21Cip1 expression completely abrogated the TCDD inhibition, and accelerated hepatocyte progression through G1 phase during the regenerative process. Analysis of the transcriptional response determined that increased p21Cip1 expression during liver regeneration involved an AhR-dependent mechanism. Chromatin immunoprecipitation studies revealed that p21Cip1 induction required AhR binding to the newly characterized nonconsensus xenobiotic response element, in conjunction with the tumor suppressor protein Kruppel-like factor 6 functioning as an AhR binding partner. The evidence also suggests that AhR functionality following partial hepatectomy is dependent on a p21Cip1-regulated signaling process, intimately linking AhR biology to the G1-phase cell cycle program. PMID:24431146

  13. Schisandrol B protects against acetaminophen-induced hepatotoxicity by inhibition of CYP-mediated bioactivation and regulation of liver regeneration.

    PubMed

    Jiang, Yiming; Fan, Xiaomei; Wang, Ying; Chen, Pan; Zeng, Hang; Tan, Huasen; Gonzalez, Frank J; Huang, Min; Bi, Huichang

    2015-01-01

    Acetaminophen (APAP) overdose is the most frequent cause of drug-induced acute liver failure. Schisandra sphenanthera is a traditional hepato-protective Chinese medicine and Schisandrol B (SolB) is one of its major active constituents. In this study, the protective effect of SolB against APAP-induced acute hepatotoxicity in mice and the involved mechanisms were investigated. Morphological and biochemical assessments clearly demonstrated a protective effect of SolB against APAP-induced liver injury. SolB pretreatment significantly attenuated the increases in alanine aminotransferase and aspartate aminotransferase activity, and prevented elevated hepatic malondialdehyde formation and the depletion of mitochondrial glutathione (GSH) in a dose-dependent manner. SolB also dramatically altered APAP metabolic activation by inhibiting the activities of CYP2E1 and CYP3A11, which was evidenced by significant inhibition of the formation of the oxidized APAP metabolite NAPQI-GSH. A molecular docking model also predicted that SolB had potential to interact with the CYP2E1 and CYP3A4 active sites. In addition, SolB abrogated APAP-induced activation of p53 and p21, and increased expression of liver regeneration and antiapoptotic-related proteins such as cyclin D1 (CCND1), PCNA, and BCL-2. This study demonstrated that SolB exhibited a significant protective effect toward APAP-induced liver injury, potentially through inhibition of CYP-mediated APAP bioactivation and regulation of the p53, p21, CCND1, PCNA, and BCL-2 to promote liver regeneration. PMID:25319358

  14. Schisandrol B protects against acetaminophen-induced hepatotoxicity by inhibition of CYP-mediated bioactivation and regulation of liver regeneration.

    PubMed

    Jiang, Yiming; Fan, Xiaomei; Wang, Ying; Chen, Pan; Zeng, Hang; Tan, Huasen; Gonzalez, Frank J; Huang, Min; Bi, Huichang

    2015-01-01

    Acetaminophen (APAP) overdose is the most frequent cause of drug-induced acute liver failure. Schisandra sphenanthera is a traditional hepato-protective Chinese medicine and Schisandrol B (SolB) is one of its major active constituents. In this study, the protective effect of SolB against APAP-induced acute hepatotoxicity in mice and the involved mechanisms were investigated. Morphological and biochemical assessments clearly demonstrated a protective effect of SolB against APAP-induced liver injury. SolB pretreatment significantly attenuated the increases in alanine aminotransferase and aspartate aminotransferase activity, and prevented elevated hepatic malondialdehyde formation and the depletion of mitochondrial glutathione (GSH) in a dose-dependent manner. SolB also dramatically altered APAP metabolic activation by inhibiting the activities of CYP2E1 and CYP3A11, which was evidenced by significant inhibition of the formation of the oxidized APAP metabolite NAPQI-GSH. A molecular docking model also predicted that SolB had potential to interact with the CYP2E1 and CYP3A4 active sites. In addition, SolB abrogated APAP-induced activation of p53 and p21, and increased expression of liver regeneration and antiapoptotic-related proteins such as cyclin D1 (CCND1), PCNA, and BCL-2. This study demonstrated that SolB exhibited a significant protective effect toward APAP-induced liver injury, potentially through inhibition of CYP-mediated APAP bioactivation and regulation of the p53, p21, CCND1, PCNA, and BCL-2 to promote liver regeneration.

  15. Scar formation and lack of regeneration in adult and neonatal liver after stromal injury.

    PubMed

    Masuzaki, Ryota; Zhao, Sophia R; Csizmadia, Eva; Yannas, Ioannis; Karp, Seth J

    2013-01-01

    Known as a uniquely regenerative tissue, the liver shows a remarkable capacity to heal without scarring after many types of acute injury. In contrast, during chronic liver disease, the liver responds with fibrosis, which can progress to cirrhosis and ultimately liver failure. The cause of this shift from a nonfibrotic to a fibrotic response is unknown. We hypothesized that stromal injury is a key event that prevents restoration of normal liver architecture. To test this, we developed a model of stromal injury using a surgical incision through the normal liver in adult and neonatal mice. This injury produces minimal cell death but locally complete stromal (extracellular matrix) disruption. The adult liver responds with inflammation and stellate cell activation, culminating in fibrosis characterized by collagen deposition. This sequence of events is remarkably similar to the fibrotic response leading to cirrhosis. Studies in neonates reveal a similar fibrotic response to a stromal injury. These findings suggest that extracellular matrix disruption leads not to regeneration but rather to scar, similar to other mammalian organs. These findings may shed light on the pathogenesis of chronic liver disease, and suggest therapeutic strategies. PMID:23228176

  16. Human mesenchymal stem cell-engineered hepatic cell sheets accelerate liver regeneration in mice

    PubMed Central

    Itaba, Noriko; Matsumi, Yoshiaki; Okinaka, Kaori; Ashla, An Afida; Kono, Yohei; Osaki, Mitsuhiko; Morimoto, Minoru; Sugiyama, Naoyuki; Ohashi, Kazuo; Okano, Teruo; Shiota, Goshi

    2015-01-01

    Mesenchymal stem cells (MSCs) are an attractive cell source for cell therapy. Based on our hypothesis that suppression of Wnt/β-catenin signal enhances hepatic differentiation of human MSCs, we developed human mesenchymal stem cell-engineered hepatic cell sheets by a small molecule compound. Screening of 10 small molecule compounds was performed by WST assay, TCF reporter assay, and albumin mRNA expression. Consequently, hexachlorophene suppressed TCF reporter activity in time- and concentration-dependent manner. Hexachlorophene rapidly induced hepatic differentiation of human MSCs judging from expression of liver-specific genes and proteins, PAS staining, and urea production. The effect of orthotopic transplantation of human mesenchymal stem cell-engineered hepatic cell sheets against acute liver injury was examined in one-layered to three-layered cell sheets system. Transplantation of human mesenchymal stem cell-engineered hepatic cell sheets enhanced liver regeneration and suppressed liver injury. The survival rates of the mice were significantly improved. High expression of complement C3 and its downstream signals including C5a, NF-κB, and IL-6/STAT-3 pathway was observed in hepatic cell sheets-grafted tissues. Expression of phosphorylated EGFR and thioredoxin is enhanced, resulting in reduction of oxidative stress. These findings suggest that orthotopic transplantation of hepatic cell sheets manufactured from MSCs accelerates liver regeneration through complement C3, EGFR and thioredoxin. PMID:26553591

  17. Integrative proteomic and microRNA analysis of the priming phase during rat liver regeneration.

    PubMed

    Geng, Xiaofang; Chang, Cuifang; Zang, Xiayan; Sun, Jingyan; Li, Pengfei; Guo, Jianli; Xu, Cunshuan

    2016-01-10

    The partial hepatectomy (PH) model provides an effective medium for study of liver regeneration (LR). Considering that LR is regulated by microRNAs (miRNAs), investigation of the regulatory role of miRNAs is critical for revealing how regenerative processes are initiated and controlled. Using high-throughput sequencing technology, we examined miRNA expression profiles of the regenerating rat liver after PH, and found that 23 miRNAs were related to rat LR. Among them, several miRNAs were significantly altered at 2h and 6h after PH, corresponding to the priming phase of LR. Furthermore, we examined the protein profiles in the regenerating rat liver at 2h and 6h after PH by iTRAQ coupled with LC-MS/MS, and found that 278 proteins were significantly changed. Subsequently, an integrative proteomic and microRNA analysis by Ingenuity Pathway Analysis 9.0 (IPA) software showed that miR-125a, miR-143, miR-150, miR-181c, miR-182, miR-183, miR-199a, miR-429 regulated the priming phase of rat LR by modulating the expression of proteins involved in networks critical for cell apoptosis, cell survival, cell cycle, inflammatory response, metabolism, etc. Thus, our studies provide novel evidence for a functional molecular network populated by the down-regulated targets of the up-regulated miRNAs in the priming phase of rat LR.

  18. Liver growth factor as a tissue regenerating factor in neurodegenerative diseases.

    PubMed

    Gonzalo-Gobernado, Rafael; Calatrava-Ferreras, Lucia; Perucho, Juan; Reimers, Diana; Casarejos, MarIa J; Herranz, Antonio S; Jimenez-Escrig, Adriano; Diaz-Gil, Juan J; Bazan, Eulalia

    2014-01-01

    Liver growth factor (LGF) is a hepatic mitogen purified by our group in 1986. In the following years we demonstrated its activity both in "in vivo" and "in vitro" systems, stimulating hepatocytes mitogenesis as well as liver regeneration in several models of liver injury. Furthermore, we established its chemical composition (albumin-bilirubin complex) and its mitogenic actions in liver. From 2000 onwards we used LGF as a tissue regenerating factor in several models of extrahepatic diseases. The use of Liver growth factor as a neural tissue regenerator has been recently protected (Patent No US 2014/8,642,551 B2). LGF administration stimulates neurogenesis and neuron survival, promotes migration of newly generated neurons, and induces the outgrowth of striatal dopaminergic terminals in 6-hidroxydopamine-lesioned rats. Furthermore, LGF treatment raises striatal dopamine levels and protects dopaminergic neurons in hemiparkinsonian animals. LGF also stimulates survival of grafted foetal neural stem cells in the damaged striatum, reduces rotational behaviour and improves motor coordination. Interestingly, LGF also exerts a neuroprotective role both in an experimental model of cerebellar ataxia and in a model of Friedrich´s ataxia. Microglia seem to be the cellular target of LGF in the CNS. Moreover, the activity of the factor could be mediated by the stimulation of MAPK´s signalling pathway and by regulating critical proteins for cell survival, such as Bcl-2 and phospho-CREB. Since the factor shows neuroprotective and neurorestorative effects we propose LGF as a patented novel therapeutic tool that may be useful for the treatment of Parkinson´s disease and cerebellar ataxias. Currently, our studies have been extended to other neurological disorders such as Alzheimer's disease (Patent No: US 2014/0113859 A1). PMID:25537484

  19. Polysome trafficking of transcripts and microRNAs in regenerating liver after partial hepatectomy.

    PubMed

    Kren, Betsy T; Wong, Phillip Y-P; Shiota, Akira; Zhang, Xiaoxiao; Zeng, Yan; Steer, Clifford J

    2009-12-01

    Liver regeneration after 70% partial hepatectomy (PH) in rats induces >95% of hepatocytes to undergo two rounds of semisynchronous cell replication. Gene expression is controlled primarily by posttranscriptional processing, including changes in mRNA stability. However, the translational activity of a specific mRNA can also be modulated after PH, resulting in significant uncoupling of protein and transcript levels relative to quiescent liver for many genes including c-myc and p53. Although the precise mechanism by which this uncoupling occurs is unknown, the polysomal association of mRNA and microRNA (miRNA) can significantly modulate rate of decay as well as translational activity. Thus we characterized the association of c-myc and p53 mRNAs and miRNAs in free and cytoskeleton- and membrane-bound polysome populations 3, 6, and 24 h after PH. The transcripts for c-myc and p53 were differentially distributed in the three discrete polysome populations, and this was dramatically modulated during liver regeneration. Nascent polysome-associated p53 and c-myc proteins were also differentially expressed in the free and cytoskeleton- and membrane-bound polysomes and significantly uncoupled from transcript levels relative to nonresected liver. At least 85 miRNAs were associated with the three polysome populations, and their abundance and distribution changed significantly during liver regeneration. These data suggest that posttranscriptional control of c-myc and p53 protein expression is associated with the translocation of transcripts between the different polyribosomes. The alteration of expression for the same transcript in different polysome populations may, in part, be due to the action of miRNAs.

  20. Liver Growth Factor as a Tissue Regenerating Factor in Neurodegenerative Diseases

    PubMed Central

    Gonzalo-Gobernado, Rafael; Calatrava-Ferreras, Lucia; Perucho, Juan; Reimers, Diana; Casarejos, María J.; Herranz, Antonio S.; Jiménez-Escrig, Adriano; Díaz-Gil, Juan J.; Bazán, Eulalia

    2014-01-01

    Liver growth factor (LGF) is a hepatic mitogen purified by our group in 1986. In the following years we demonstrated its activity both in “in vivo” and “in vitro” systems, stimulating hepatocytes mitogenesis as well as liver regeneration in several models of liver injury. Furthermore, we established its chemical composition (albumin-bilirubin complex) and its mitogenic actions in liver. From 2000 onwards we used LGF as a tissue regenerating factor in several models of extrahepatic diseases. The use of Liver growth factor as a neural tissue regenerator has been recently protected (Patent No US 2014/8,642,551 B2). LGF administration stimulates neurogenesis and neuron survival, promotes migration of newly generated neurons, and induces the outgrowth of striatal dopaminergic terminals in 6-hidroxydopamine-lesioned rats. Furthermore, LGF treatment raises striatal dopamine levels and protects dopaminergic neurons in hemiparkinsonian animals. LGF also stimulates survival of grafted foetal neural stem cells in the damaged striatum, reduces rotational behaviour and improves motor coordination. Interestingly, LGF also exerts a neuroprotective role both in an experimental model of cerebellar ataxia and in a model of Friedrich´s ataxia. Microglia seem to be the cellular target of LGF in the CNS. Moreover, the activity of the factor could be mediated by the stimulation of MAPK´s signalling pathway and by regulating critical proteins for cell survival, such as Bcl-2 and phospho-CREB. Since the factor shows neuroprotective and neurorestorative effects we propose LGF as a patented novel therapeutic tool that may be useful for the treatment of Parkinson´s disease and cerebellar ataxias. Currently, our studies have been extended to other neurological disorders such as Alzheimer’s disease (Patent No: US 2014/0113859 A1). PMID:25537484

  1. Liver growth factor as a tissue regenerating factor in neurodegenerative diseases.

    PubMed

    Gonzalo-Gobernado, Rafael; Calatrava-Ferreras, Lucia; Perucho, Juan; Reimers, Diana; Casarejos, MarIa J; Herranz, Antonio S; Jimenez-Escrig, Adriano; Diaz-Gil, Juan J; Bazan, Eulalia

    2014-01-01

    Liver growth factor (LGF) is a hepatic mitogen purified by our group in 1986. In the following years we demonstrated its activity both in "in vivo" and "in vitro" systems, stimulating hepatocytes mitogenesis as well as liver regeneration in several models of liver injury. Furthermore, we established its chemical composition (albumin-bilirubin complex) and its mitogenic actions in liver. From 2000 onwards we used LGF as a tissue regenerating factor in several models of extrahepatic diseases. The use of Liver growth factor as a neural tissue regenerator has been recently protected (Patent No US 2014/8,642,551 B2). LGF administration stimulates neurogenesis and neuron survival, promotes migration of newly generated neurons, and induces the outgrowth of striatal dopaminergic terminals in 6-hidroxydopamine-lesioned rats. Furthermore, LGF treatment raises striatal dopamine levels and protects dopaminergic neurons in hemiparkinsonian animals. LGF also stimulates survival of grafted foetal neural stem cells in the damaged striatum, reduces rotational behaviour and improves motor coordination. Interestingly, LGF also exerts a neuroprotective role both in an experimental model of cerebellar ataxia and in a model of Friedrich´s ataxia. Microglia seem to be the cellular target of LGF in the CNS. Moreover, the activity of the factor could be mediated by the stimulation of MAPK´s signalling pathway and by regulating critical proteins for cell survival, such as Bcl-2 and phospho-CREB. Since the factor shows neuroprotective and neurorestorative effects we propose LGF as a patented novel therapeutic tool that may be useful for the treatment of Parkinson´s disease and cerebellar ataxias. Currently, our studies have been extended to other neurological disorders such as Alzheimer's disease (Patent No: US 2014/0113859 A1).

  2. Clustering Nuclear Receptors in Liver Regeneration Identifies Candidate Modulators of Hepatocyte Proliferation and Hepatocarcinoma

    PubMed Central

    Graziano, Giusi; D'Orazio, Andria; Cariello, Marica; Massafra, Vittoria; Salvatore, Lorena; Martelli, Nicola; Murzilli, Stefania; Sasso, Giuseppe Lo; Mariani-Costantini, Renato; Moschetta, Antonio

    2014-01-01

    Background & Aims Liver regeneration (LR) is a valuable model for studying mechanisms modulating hepatocyte proliferation. Nuclear receptors (NRs) are key players in the control of cellular functions, being ideal modulators of hepatic proliferation and carcinogenesis. Methods & Results We used a previously validated RT-qPCR platform to profile modifications in the expression of all 49 members of the NR superfamily in mouse liver during LR. Twenty-nine NR transcripts were significantly modified in their expression during LR, including fatty acid (peroxisome proliferator-activated receptors, PPARs) and oxysterol (liver X receptors, Lxrs) sensors, circadian masters RevErbα and RevErbβ, glucocorticoid receptor (Gr) and constitutive androxane receptor (Car). In order to detect the NRs that better characterize proliferative status vs. proliferating liver, we used the novel Random Forest (RF) analysis to selected a trio of down-regulated NRs (thyroid receptor alpha, Trα; farsenoid X receptor beta, Fxrβ; Pparδ) as best discriminators of the proliferating status. To validate our approach, we further studied PPARδ role in modulating hepatic proliferation. We first confirmed the suppression of PPARδ both in LR and human hepatocellular carcinoma at protein level, and then demonstrated that PPARδ agonist GW501516 reduces the proliferative potential of hepatoma cells. Conclusions Our data suggest that NR transcriptome is modulated in proliferating liver and is a source of biomarkers and bona fide pharmacological targets for the management of liver disease affecting hepatocyte proliferation. PMID:25116592

  3. The Role of Mesothelial Cells in Liver Development, Injury, and Regeneration

    PubMed Central

    Lua, Ingrid; Asahina, Kinji

    2016-01-01

    Mesothelial cells (MCs) cover the surface of visceral organs and the parietal walls of cavities, and they synthesize lubricating fluids to create a slippery surface that facilitates movement between organs without friction. Recent studies have indicated that MCs play active roles in liver development, fibrosis, and regeneration. During liver development, the mesoderm produces MCs that form a single epithelial layer of the mesothelium. MCs exhibit an intermediate phenotype between epithelial cells and mesenchymal cells. Lineage tracing studies have indicated that during liver development, MCs act as mesenchymal progenitor cells that produce hepatic stellate cells, fibroblasts around blood vessels, and smooth muscle cells. Upon liver injury, MCs migrate inward from the liver surface and produce hepatic stellate cells or myofibroblast depending on the etiology, suggesting that MCs are the source of myofibroblasts in capsular fibrosis. Similar to the activation of hepatic stellate cells, transforming growth factor β induces the conversion of MCs into myofibroblasts. Further elucidation of the biological and molecular changes involved in MC activation and fibrogenesis will contribute to the development of novel approaches for the prevention and therapy of liver fibrosis. PMID:26934883

  4. MBSJ MCC Young Scientist Award 2012 Liver regeneration: a unique and flexible reaction depending on the type of injury.

    PubMed

    Suzuki, Atsushi

    2015-02-01

    The liver can be thought of as a mysterious organ, because it has an elegant regenerative capability. This phenomenon has been well known since ancient times and is already applied to medical treatments for severe hepatic disorders by transplanting portions of liver received from living donors. However, it was not until quite recently that the mechanism underlying the principle of liver regeneration was investigated more deeply. Recent advances in the technologies for characterizing cell properties and examining the molecular nature of cells are enabling us to understand what occurs in the regenerating liver. After acute liver damage, hepatocytes actively proliferate in response to external stimulation by humoral factors. However, in the chronically injured liver, hepatocytes cannot proliferate well, but biliary cells appearing after chronic liver damage form primitive ductules around portal veins of the liver. These biliary cells may have a multiple origin, including hepatocytes, and contain progenitor cells giving rise to both hepatocytes and biliary cells, or represent cells that can be directly converted into hepatocytes. Although liver regeneration is more complicated than we had thought, unremitting efforts by researchers will certainly connect the numerous findings obtained in basic research with the development of new therapeutic strategies for liver diseases.

  5. MBSJ MCC Young Scientist Award 2012 Liver regeneration: a unique and flexible reaction depending on the type of injury

    PubMed Central

    Suzuki, Atsushi

    2015-01-01

    The liver can be thought of as a mysterious organ, because it has an elegant regenerative capability. This phenomenon has been well known since ancient times and is already applied to medical treatments for severe hepatic disorders by transplanting portions of liver received from living donors. However, it was not until quite recently that the mechanism underlying the principle of liver regeneration was investigated more deeply. Recent advances in the technologies for characterizing cell properties and examining the molecular nature of cells are enabling us to understand what occurs in the regenerating liver. After acute liver damage, hepatocytes actively proliferate in response to external stimulation by humoral factors. However, in the chronically injured liver, hepatocytes cannot proliferate well, but biliary cells appearing after chronic liver damage form primitive ductules around portal veins of the liver. These biliary cells may have a multiple origin, including hepatocytes, and contain progenitor cells giving rise to both hepatocytes and biliary cells, or represent cells that can be directly converted into hepatocytes. Although liver regeneration is more complicated than we had thought, unremitting efforts by researchers will certainly connect the numerous findings obtained in basic research with the development of new therapeutic strategies for liver diseases. PMID:25534695

  6. Glugacon-like peptide-2: broad receptor expression, limited therapeutic effect on intestinal inflammation and novel role in liver regeneration.

    PubMed

    El-Jamal, Noura; Erdual, Edmone; Neunlist, Michel; Koriche, Dine; Dubuquoy, Caroline; Maggiotto, Francois; Chevalier, Julien; Berrebi, Dominique; Dubuquoy, Laurent; Boulanger, Eric; Cortot, Antoine; Desreumaux, Pierre

    2014-08-01

    The glucagon-like peptide 2 (GLP-2) is an intestinotrophic hormone with growth promoting and anti-inflammatory actions. However, the full biological functions of GLP-2 and the localization of its receptor (GLP-2R) remain controversial. Among cell lines tested, the expression of GLP-2R transcript was detected in human colonic myofibroblasts (CCD-18Co) and in primary culture of rat enteric nervous system but not in intestinal epithelial cell lines, lymphocytes, monocytes, or endothelial cells. Surprisingly, GLP-2R was expressed in murine (GLUTag), but not human (NCI-H716) enteroendocrine cells. The screening of GLP-2R mRNA in mice organs revealed an increasing gradient of GLP-2R toward the distal gut. An unexpected expression was detected in the mesenteric fat, mesenteric lymph nodes, bladder, spleen, and liver, particularly in hepatocytes. In two mice models of trinitrobenzene sulfonic acid (TNBS)- and dextran sulfate sodium (DSS)-induced colitis, the colonic expression of GLP-2R mRNA was decreased by 60% compared with control mice. Also, GLP-2R mRNA was significantly downregulated in intestinal tissues of inflammatory bowel disease patients. Therapeutically, GLP-2 showed a weak restorative effect on intestinal inflammation during TNBS-induced colitis as assessed by macroscopic score and inflammatory markers. Finally, GLP-2 treatment accelerated mouse liver regeneration following partial hepatectomy as assessed by histological and molecular analyses. In conclusion, the limited therapeutic effect of GLP-2 on colonic inflammation dampens its utility in the management of severe inflammatory intestinal disorders. However, the role of GLP-2 in liver regeneration is a novelty that might introduce GLP-2 into the management of liver diseases and emphasizes on the importance of elucidating other extraintestinal functions of GLP-2. PMID:24875097

  7. Anandamide drives cell cycle progression through CB1 receptors in a rat model of synchronized liver regeneration.

    PubMed

    Pisanti, Simona; Picardi, Paola; Pallottini, Valentina; Martini, Chiara; Petrosino, Stefania; Proto, Maria Chiara; Vitale, Mario; Laezza, Chiara; Gazzerro, Patrizia; Di Marzo, Vincenzo; Bifulco, Maurizio

    2015-12-01

    The endocannabinoid system, through cannabinoid receptor signaling by endocannabinoids, is involved in a wide range of functions and physiopathological conditions. To date, very little is known concerning the role of the endocannabinoids in the control and regulation of cell proliferation. An anti-proliferative action of CB1 signaling blockade in neurogenesis and angiogenesis argues in favor of proliferation-promoting functions of endocannabinoids through CB1 receptors when pro-growth signals are present. Furthermore, liver regeneration, a useful in vivo model of synchronized cell proliferation, is characterized by a peak of anandamide that elicits through CB1 receptor, the expression of critical mitosis genes. The aim of this study was to focus on the timing of endocannabinoid signaling changes during the different phases of the cell cycle, exploiting the rat liver regeneration model following partial hepatectomy, the most useful to study synchronized cell cycle in vivo. Hepatic regeneration led to increased levels of anandamide and endocannabinoid-like molecules oleoylethanolamide (OEA) and palmitoylethanolamide (PEA) in the G1 phase of the cell cycle, with a concomitant increase in CB1 mRNA levels, whose protein expression peaked later during the S phase. Blocking of CB1 receptor with a low dose of the selective antagonist/inverse agonist SR141716 (0.7 mg/kg/dose) affected cell cycle progression reducing the expression of PCNA, and through the inhibition of pERK and pSTAT3 pathways. These results support the notion that the signaling mediated by anandamide through CB1 receptor may be important for the entry and progression of cells into the cell cycle and hence for their proliferation under mitogenic signals.

  8. Blocking of G1/S transition and cell death in the regenerating liver of Hepatitis B virus X protein transgenic mice

    SciTech Connect

    Wu, B.-K.; Li, C.-C.; Chen, H.-J.; Chang, J.-L.; Jeng, K.-S.; Chou, C.-K.; Hsu, M.-T.; Tsai, T.-F. . E-mail: tftsai@ym.edu.tw

    2006-02-17

    The Hepatitis B virus X (HBx) protein has been strongly implicated in the carcinogenesis of hepatocellular carcinoma (HCC). However, effects of the HBx protein on cell proliferation and cell death are controversial. This study investigates the effects of the HBx protein on liver regeneration in two independent lines of HBx transgenic mice, which developed HCC at around 14 to 16 months of age. High mortality, lower liver mass restoration, and impaired liver regeneration were found in the HBx transgenic mice post-hepatectomy. The levels of alanine aminotransferase and {alpha}-fetoprotein detected post-hepatectomy increased significantly in the HBx transgenic livers, indicating that they were more susceptible to damage during the regenerative process. Prolonged activation of the immediate-early genes in the HBx transgenic livers suggested that the HBx protein creates a strong effect by promoting the transition of the quiescent hepatocytes from G0 to G1 phase. However, impaired DNA synthesis and mitosis, as well as inhibited activation of G1, S, and G2/M markers, were detected. These results indicated that HBx protein exerted strong growth arrest on hepatocytes and imbalanced cell-cycle progression resulting in the abnormal cell death; this was accompanied by severe fat accumulation and impaired glycogen storage in the HBx transgenic livers. In conclusion, this study provides First physiological evidence that HBx protein blocks G1/S transition of the hepatocyte cell-cycle progression and causes both a failure of liver functionality and cell death in the regenerating liver of the HBx transgenic mice.

  9. Identification of an epigenetic signature of early mouse liver regeneration that is disrupted by Zn-HDAC inhibition.

    PubMed

    Huang, Jiansheng; Schriefer, Andrew E; Yang, Wei; Cliften, Paul F; Rudnick, David A

    2014-11-01

    Liver regeneration has been well studied with hope of discovering strategies to improve liver disease outcomes. Nevertheless, the signals that initiate such regeneration remain incompletely defined, and translation of mechanism-based pro-regenerative interventions into new treatments for hepatic diseases has not yet been achieved. We previously reported the isoform-specific regulation and essential function of zinc-dependent histone deacetylases (Zn-HDACs) during mouse liver regeneration. Those data suggest that epigenetically regulated anti-proliferative genes are deacetylated and transcriptionally suppressed by Zn-HDAC activity or that pro-regenerative factors are acetylated and induced by such activity in response to partial hepatectomy (PH). To investigate these possibilities, we conducted genome-wide interrogation of the liver histone acetylome during early PH-induced liver regeneration in mice using acetyL-histone chromatin immunoprecipitation and next generation DNA sequencing. We also compared the findings of that study to those seen during the impaired regenerative response that occurs with Zn-HDAC inhibition. The results reveal an epigenetic signature of early liver regeneration that includes both hyperacetylation of pro-regenerative factors and deacetylation of anti-proliferative and pro-apoptotic genes. Our data also show that administration of an anti-regenerative regimen of the Zn-HDAC inhibitor suberoylanilide hydroxamic acid (SAHA) not only disrupts gene-specific pro-regenerative changes in liver histone deacetylation but also reverses PH-induced effects on histone hyperacetylation. Taken together, these studies offer new insight into and suggest novel hypotheses about the epigenetic mechanisms that regulate liver regeneration.

  10. Hybrid Periportal Hepatocytes Regenerate the Injured Liver without Giving Rise to Cancer.

    PubMed

    Font-Burgada, Joan; Shalapour, Shabnam; Ramaswamy, Suvasini; Hsueh, Brian; Rossell, David; Umemura, Atsushi; Taniguchi, Koji; Nakagawa, Hayato; Valasek, Mark A; Ye, Li; Kopp, Janel L; Sander, Maike; Carter, Hannah; Deisseroth, Karl; Verma, Inder M; Karin, Michael

    2015-08-13

    Compensatory proliferation triggered by hepatocyte loss is required for liver regeneration and maintenance but also promotes development of hepatocellular carcinoma (HCC). Despite extensive investigation, the cells responsible for hepatocyte restoration or HCC development remain poorly characterized. We used genetic lineage tracing to identify cells responsible for hepatocyte replenishment following chronic liver injury and queried their roles in three distinct HCC models. We found that a pre-existing population of periportal hepatocytes, located in the portal triads of healthy livers and expressing low amounts of Sox9 and other bile-duct-enriched genes, undergo extensive proliferation and replenish liver mass after chronic hepatocyte-depleting injuries. Despite their high regenerative potential, these so-called hybrid hepatocytes do not give rise to HCC in chronically injured livers and thus represent a unique way to restore tissue function and avoid tumorigenesis. This specialized set of pre-existing differentiated cells may be highly suitable for cell-based therapy of chronic hepatocyte-depleting disorders. PMID:26276631

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

    PubMed

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

    2014-06-01

    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.

  12. Low-power laser irradiation fails to improve liver regeneration in elderly rats at 48 h after 70 % resection.

    PubMed

    Araújo, Tiago G; Oliveira, Alexandre G; Tobar, Natália; Moreira, Luciana R; Reis, Edmyr R; Nicola, Ester M D; de L Jorge, Gracinda; dos R Tártaro, Rodolfo; Boin, Ilka F S F; Saad, Mário J Abdalla; Teixeira, Antonio R Franchi

    2015-09-01

    The liver regeneration is an important clinical issue after major hepatectomies. Unfortunately, many organs (including the liver) exhibit age-related impairments regarding their regenerative capacity. Recent studies found that low-power laser irradiation (LPLI) has a stimulatory effect on the liver regeneration process. However, its effects in elderly remain unknown. Thus, this study aimed to investigate the main molecular mechanisms involved in liver regeneration of partially hepatectomized elderly rats exposed to LPLI. The effects of 15 min of LPLI (wavelength of 632.8 nm; fluence of 0.97 J/cm(2); total energy delivered of 3.6 J) were evaluated in hepatectomized elderly Wistar male rats. Afterwards, through immunoblotting approaches, the protein expression and phosphorylation levels of hepatocyte growth factor (HGF), Met, Akt and Erk 1/2 signaling pathways as well as the proliferating cell nuclear antigen (PCNA) were investigated. It was observed that LPLI was not able to improve liver regeneration in elderly rats as evidenced by the lack of improvement of HGF and PCNA protein expression or phosphorylation levels of Met, Akt and Erk 1/2 in the remnant livers. In sum, this study demonstrated that the main molecular pathway, i.e. HGF/Met → Akt and Erk 1/2 → PCNA, involved in the hepatic regeneration process was not improved by LPLI in elderly hepatectomized rats, which in turn rules out LPLI as an adjuvant therapy, as observed in this protocol of liver regeneration evaluation (i.e. at 48 h after 70 % resection), in elderly.

  13. Function and expression study uncovered hepatocyte plasma membrane ecto-ATP synthase as a novel player in liver regeneration.

    PubMed

    Taurino, Federica; Giannoccaro, Caterina; Sardanelli, Anna Maria; Cavallo, Alessandro; De Luca, Elisa; Santacroce, Salvatore; Papa, Sergio; Zanotti, Franco; Gnoni, Antonio

    2016-08-15

    ATP synthase, canonically mitochondrially located, is reported to be ectopically expressed on the plasma membrane outer face of several cell types. We analysed, for the first time, the expression and catalytic activities of the ecto- and mitochondrial ATP synthase during liver regeneration. Liver regeneration was induced in rats by two-thirds partial hepatectomy. The protein level and the ATP synthase and/or hydrolase activities of the hepatocyte ecto- and mitochondrial ATP synthase were analysed on freshly isolated hepatocytes and mitochondria from control, sham-operated and partial hepatectomized rats. During the priming phase of liver regeneration, 3 h after partial hepatectomy, liver mitochondria showed a marked lowering of the ATP synthase protein level that was reflected in the impairment of both ATP synthesis and hydrolysis. The ecto-ATP synthase level, in 3 h partial hepatectomized hepatocytes, was decreased similarly to the level of the mitochondrial ATP synthase, associated with a lowering of the ecto-ATP hydrolase activity coupled to proton influx. Noteworthily, the ecto-ATP synthase activity coupled to proton efflux was completely inhibited in 3 h partial hepatectomized hepatocytes, even in the presence of a marked intracellular acidification that would sustain it as in control and sham-operated hepatocytes. At the end of the liver regeneration, 7 days after partial hepatectomy, the level and the catalytic activities of the ecto- and mitochondrial ATP synthase reached the control and sham-operated values. The specific modulation of hepatocyte ecto-ATP synthase catalytic activities during liver regeneration priming phase may modulate the extracellular ADP/ATP levels and/or proton influx/efflux trafficking, making hepatocyte ecto-ATP synthase a candidate for a novel player in the liver regeneration process. PMID:27287557

  14. Function and expression study uncovered hepatocyte plasma membrane ecto-ATP synthase as a novel player in liver regeneration.

    PubMed

    Taurino, Federica; Giannoccaro, Caterina; Sardanelli, Anna Maria; Cavallo, Alessandro; De Luca, Elisa; Santacroce, Salvatore; Papa, Sergio; Zanotti, Franco; Gnoni, Antonio

    2016-08-15

    ATP synthase, canonically mitochondrially located, is reported to be ectopically expressed on the plasma membrane outer face of several cell types. We analysed, for the first time, the expression and catalytic activities of the ecto- and mitochondrial ATP synthase during liver regeneration. Liver regeneration was induced in rats by two-thirds partial hepatectomy. The protein level and the ATP synthase and/or hydrolase activities of the hepatocyte ecto- and mitochondrial ATP synthase were analysed on freshly isolated hepatocytes and mitochondria from control, sham-operated and partial hepatectomized rats. During the priming phase of liver regeneration, 3 h after partial hepatectomy, liver mitochondria showed a marked lowering of the ATP synthase protein level that was reflected in the impairment of both ATP synthesis and hydrolysis. The ecto-ATP synthase level, in 3 h partial hepatectomized hepatocytes, was decreased similarly to the level of the mitochondrial ATP synthase, associated with a lowering of the ecto-ATP hydrolase activity coupled to proton influx. Noteworthily, the ecto-ATP synthase activity coupled to proton efflux was completely inhibited in 3 h partial hepatectomized hepatocytes, even in the presence of a marked intracellular acidification that would sustain it as in control and sham-operated hepatocytes. At the end of the liver regeneration, 7 days after partial hepatectomy, the level and the catalytic activities of the ecto- and mitochondrial ATP synthase reached the control and sham-operated values. The specific modulation of hepatocyte ecto-ATP synthase catalytic activities during liver regeneration priming phase may modulate the extracellular ADP/ATP levels and/or proton influx/efflux trafficking, making hepatocyte ecto-ATP synthase a candidate for a novel player in the liver regeneration process.

  15. The mitochondrial import gene tomm22 is specifically required for hepatocyte survival and provides a liver regeneration model

    PubMed Central

    Curado, Silvia; Ober, Elke A.; Walsh, Susan; Cortes-Hernandez, Paulina; Verkade, Heather; Koehler, Carla M.; Stainier, Didier Y. R.

    2010-01-01

    SUMMARY Understanding liver development should lead to greater insights into liver diseases and improve therapeutic strategies. In a forward genetic screen for genes regulating liver development in zebrafish, we identified a mutant – oliver – that exhibits liver-specific defects. In oliver mutants, the liver is specified, bile ducts form and hepatocytes differentiate. However, the hepatocytes die shortly after their differentiation, and thus the resulting mutant liver consists mainly of biliary tissue. We identified a mutation in the gene encoding translocase of the outer mitochondrial membrane 22 (Tomm22) as responsible for this phenotype. Mutations in tomm genes have been associated with mitochondrial dysfunction, but most studies on the effect of defective mitochondrial protein translocation have been carried out in cultured cells or unicellular organisms. Therefore, the tomm22 mutant represents an important vertebrate genetic model to study mitochondrial biology and hepatic mitochondrial diseases. We further found that the temporary knockdown of Tomm22 levels by morpholino antisense oligonucleotides causes a specific hepatocyte degeneration phenotype that is reversible: new hepatocytes repopulate the liver as Tomm22 recovers to wild-type levels. The specificity and reversibility of hepatocyte ablation after temporary knockdown of Tomm22 provides an additional model to study liver regeneration, under conditions where most hepatocytes have died. We used this regeneration model to analyze the signaling commonalities between hepatocyte development and regeneration. PMID:20483998

  16. Vascular endothelial growth factor and nitric oxide in rat liver regeneration.

    PubMed

    Ronco, Maria Teresa; Francés, Daniel; de Luján Alvarez, Maria; Quiroga, Ariel; Monti, Juan; Parody, Juan Pablo; Pisani, Gerardo; Carrillo, Maria Cristina; Carnovale, Cristina Ester

    2007-08-01

    In this work we investigated the role of nitric oxide (NO) in the angiogenesis mediated by vascular endothelial growth factor (VEGF) during rat liver regeneration after two-thirds partial hepatectomy. Sham operated (Sh) and partially hepatectomized (PH) male Wistar rats were randomized in three experimental groups: control (treated with vehicle); pre-treated with sodium nitroprusside (SNP: 0.25 mg/kg body weight, i.v. at a rate of 1 ml/h) and pre-treated with the preferential iNOS inhibitor, aminoguanidine (AG, 100 mg/kg body weight, i.p.). Animals were killed at 5, 24 and 72 h after surgery. At 5 h post-surgery, NO production was estimated by EPR (Sh-Control: 37.65+/-10.70; PH-Control: 88.13+/-1.60(); Sh-SNP: 90.35+/-3.11(); PH-SNP: 119.5+/-12.10()(#); Sh-AG: 33.27+/-5.23, PH-AG: 36.80+/-3.40(#)) (p<0.05 vs Sh-Control; (#)p<0.05 vs PH-Control). At 24 h after PH, VEGF levels showed no difference between PH-Control and PH-SNP animals. However, after 72 h, VEGF protein levels in PH-SNP animals were found to be increased (above 300%) with respect to PH-Control. On the other hand, aminoguanidine (AG) pre-treatment blocked the rise of inhibition of NO generation and decreased VEGF expression. Our results demonstrated that NO plays a role in modulating VEGF protein expression after hepatectomy in rats. PMID:17706723

  17. Study of microRNAs related to the liver regeneration of the whitespotted bamboo shark, Chiloscyllium plagiosum.

    PubMed

    Lu, Conger; Zhang, Jie; Nie, Zuoming; Chen, Jian; Zhang, Wenping; Ren, Xiaoyuan; Yu, Wei; Liu, Lili; Jiang, Caiying; Zhang, Yaozhou; Guo, Jiangfeng; Wu, Wutong; Shu, Jianhong; Lv, Zhengbing

    2013-01-01

    To understand the mechanisms of liver regeneration better to promote research examining liver diseases and marine biology, normal and regenerative liver tissues of Chiloscyllium plagiosum were harvested 0 h and 24 h after partial hepatectomy (PH) and used to isolate small RNAs for miRNA sequencing. In total, 91 known miRNAs and 166 putative candidate (PC) miRNAs were identified for the first time in Chiloscyllium plagiosum. Through target prediction and GO analysis, 46 of 91 known miRNAs were screened specially for cellular proliferation and growth. Differential expression levels of three miRNAs (xtr-miR-125b, fru-miR-204, and hsa-miR-142-3p_R-1) related to cellular proliferation and apoptosis were measured in normal and regenerating liver tissues at 0 h, 6 h, 12 h, and 24 h using real-time PCR. The expression of these miRNAs showed a rising trend in regenerative liver tissues at 6 h and 12 h but exhibited a downward trend compared to normal levels at 24 h. Differentially expressed genes were screened in normal and regenerating liver tissues at 24 h by DDRT-PCR, and ten sequences were identified. This study provided information regarding the function of genes related to liver regeneration, deepened the understanding of mechanisms of liver regeneration, and resulted in the addition of a significant number of novel miRNAs sequences to GenBank.

  18. Four and a Half LIM Domains 1b (Fhl1b) Is Essential for Regulating the Liver versus Pancreas Fate Decision and for β-Cell Regeneration.

    PubMed

    Xu, Jin; Cui, Jiaxi; Del Campo, Aranzazu; Shin, Chong Hyun

    2016-02-01

    The liver and pancreas originate from overlapping embryonic regions, and single-cell lineage tracing in zebrafish has shown that Bone morphogenetic protein 2b (Bmp2b) signaling is essential for determining the fate of bipotential hepatopancreatic progenitors towards the liver or pancreas. Despite its pivotal role, the gene regulatory networks functioning downstream of Bmp2b signaling in this process are poorly understood. We have identified four and a half LIM domains 1b (fhl1b), which is primarily expressed in the prospective liver anlage, as a novel target of Bmp2b signaling. fhl1b depletion compromised liver specification and enhanced induction of pancreatic cells from endodermal progenitors. Conversely, overexpression of fhl1b favored liver specification and inhibited induction of pancreatic cells. By single-cell lineage tracing, we showed that fhl1b depletion led lateral endodermal cells, destined to become liver cells, to become pancreatic cells. Reversely, when fhl1b was overexpressed, medially located endodermal cells, fated to differentiate into pancreatic and intestinal cells, contributed to the liver by directly or indirectly modulating the discrete levels of pdx1 expression in endodermal progenitors. Moreover, loss of fhl1b increased the regenerative capacity of β-cells by increasing pdx1 and neurod expression in the hepatopancreatic ductal system. Altogether, these data reveal novel and critical functions of Fhl1b in the hepatic versus pancreatic fate decision and in β-cell regeneration.

  19. Four and a Half LIM Domains 1b (Fhl1b) Is Essential for Regulating the Liver versus Pancreas Fate Decision and for β-Cell Regeneration

    PubMed Central

    Xu, Jin; Cui, Jiaxi; Del Campo, Aranzazu; Shin, Chong Hyun

    2016-01-01

    The liver and pancreas originate from overlapping embryonic regions, and single-cell lineage tracing in zebrafish has shown that Bone morphogenetic protein 2b (Bmp2b) signaling is essential for determining the fate of bipotential hepatopancreatic progenitors towards the liver or pancreas. Despite its pivotal role, the gene regulatory networks functioning downstream of Bmp2b signaling in this process are poorly understood. We have identified four and a half LIM domains 1b (fhl1b), which is primarily expressed in the prospective liver anlage, as a novel target of Bmp2b signaling. fhl1b depletion compromised liver specification and enhanced induction of pancreatic cells from endodermal progenitors. Conversely, overexpression of fhl1b favored liver specification and inhibited induction of pancreatic cells. By single-cell lineage tracing, we showed that fhl1b depletion led lateral endodermal cells, destined to become liver cells, to become pancreatic cells. Reversely, when fhl1b was overexpressed, medially located endodermal cells, fated to differentiate into pancreatic and intestinal cells, contributed to the liver by directly or indirectly modulating the discrete levels of pdx1 expression in endodermal progenitors. Moreover, loss of fhl1b increased the regenerative capacity of β-cells by increasing pdx1 and neurod expression in the hepatopancreatic ductal system. Altogether, these data reveal novel and critical functions of Fhl1b in the hepatic versus pancreatic fate decision and in β-cell regeneration. PMID:26845333

  20. Four and a Half LIM Domains 1b (Fhl1b) Is Essential for Regulating the Liver versus Pancreas Fate Decision and for β-Cell Regeneration.

    PubMed

    Xu, Jin; Cui, Jiaxi; Del Campo, Aranzazu; Shin, Chong Hyun

    2016-02-01

    The liver and pancreas originate from overlapping embryonic regions, and single-cell lineage tracing in zebrafish has shown that Bone morphogenetic protein 2b (Bmp2b) signaling is essential for determining the fate of bipotential hepatopancreatic progenitors towards the liver or pancreas. Despite its pivotal role, the gene regulatory networks functioning downstream of Bmp2b signaling in this process are poorly understood. We have identified four and a half LIM domains 1b (fhl1b), which is primarily expressed in the prospective liver anlage, as a novel target of Bmp2b signaling. fhl1b depletion compromised liver specification and enhanced induction of pancreatic cells from endodermal progenitors. Conversely, overexpression of fhl1b favored liver specification and inhibited induction of pancreatic cells. By single-cell lineage tracing, we showed that fhl1b depletion led lateral endodermal cells, destined to become liver cells, to become pancreatic cells. Reversely, when fhl1b was overexpressed, medially located endodermal cells, fated to differentiate into pancreatic and intestinal cells, contributed to the liver by directly or indirectly modulating the discrete levels of pdx1 expression in endodermal progenitors. Moreover, loss of fhl1b increased the regenerative capacity of β-cells by increasing pdx1 and neurod expression in the hepatopancreatic ductal system. Altogether, these data reveal novel and critical functions of Fhl1b in the hepatic versus pancreatic fate decision and in β-cell regeneration. PMID:26845333

  1. The effect of vinyl chloride monomer, chloroethylene oxide and chloracetaldehyde on DNA synthesis in regenerating rat liver.

    PubMed

    Border, E A; Webster, I

    1977-05-01

    Vinyl chloride monomer used in the manufacture of polyvinyl chloride is a chemical of increasing industrial importance but has recently been incriminated as a carcinogen, producing a mutagenic effect after being metabolized to active metabolites. The initial effect of vinyl chloride monomer and two of its presumed metabolites, chloracetaldehyde and chloroethylene oxide, on DNA synthesis was investigated in vivo in regenerating rat liver. The established control curve for the DNA synthesis rate after partial hepatectomy demonstrated two waves of synthetic activity at 21 and 30 h. Vinyl chloride, injected intravenously immediately on completion of the operation, depressed the first wave of DNA synthesis by 49.6%. The second peak of DNA synthetic activity was similar to that of the control. Chloracetaldehyde and chloroethylene oxide both produced similar effects on the first wave of DNA synthesis after partial hepatectomy, inhibiting the DNA synthesis rate by approx. 50%. After a regenerating period of 27 h, however, they produced very different effects, chloroethylene oxide raising the control DNA synthesis rate at 30 h by 49% while chloracetaldehyde tended to desynchronize the well-defined second peak of the control. The test compounds have been compared to literature reports of the inhibitory effects of various carcinogens on DNA synthesis.

  2. Scavenging peroxynitrite with glutathione promotes regeneration and enhances survival during acetaminophen-induced liver injury in mice.

    PubMed

    Bajt, Mary Lynn; Knight, Tamara R; Farhood, Anwar; Jaeschke, Hartmut

    2003-10-01

    Acetaminophen (AAP) overdose causes formation of peroxynitrite in centrilobular hepatocytes. Treatment with glutathione (GSH) after AAP accelerated recovery of mitochondrial GSH levels, which scavenged peroxynitrite and protected against liver injury at 6 h. The objective of this investigation was to evaluate whether GSH treatment has a long-term protective effect against AAP-induced injury and whether it promotes liver regeneration. AAP (300 mg/kg) induced severe centrilobular necrosis and increased plasma alanine aminotransferase (ALT) activities (24 h: 3680 +/- 320 U/liter) in fasted C3Heb/FeJ mice. Only 53% of the animals survived for 24 h. Hepatic glutathione levels were still suppressed by 62% at 24 h compared with untreated controls (19.7 +/- 2.6 micromol/g). Glutathione disulfide (GSSG) concentrations were elevated by 455% compared with controls (74 +/- 3 nmol/g liver). Treatment with GSH at 1.5 h after AAP treatment attenuated liver necrosis and plasma ALT activities by 62 to 66% at 24 h. All animals survived up to 7 days. The hepatic GSH content recovered to control values; however, the GSSG levels were still elevated at 48 h (252 +/- 26 nmol/g). Expression of proliferating cell nuclear antigen (PCNA) and cell cycle proteins cyclin D1 and p21 were not detectable in controls or after AAP alone. Treatment with GSH after AAP induced expression of cyclin D1, p21, and PCNA (12-48 h). Thus, GSH treatment after AAP provided long-term hepatoprotection and promotes progression of cell cycle activation in hepatocytes.

  3. Significance of increased `splenic uptake' on liver scintiscanning

    PubMed Central

    Eddleston, A. L. W. F.; Blendis, L. M.; Osborn, S. B.; Williams, Roger

    1969-01-01

    Peak activity over the spleen as a percentage of peak activity over the liver was measured in 265 99mTechnetium sulphur colloid liver scintiscans. The value exceeded 70% in 50 cases. In 32 of these cirrhosis was present; the other 18 scans were from patients with a wide variety of conditions, including secondary deposits, hepatitis, and diseases involving the reticuloendothelial system. A measure of the total activity in the spleen was derived from the peak activity and the length of the spleen. In cirrhosis this was closely related to the finding of oesophageal varices thus showing the importance of a collateral circulation (which allows colloid to bypass the liver) in the increased uptake of colloid by the spleen. In eight patients with hepatosplenomegaly due to blood dyscrasia or disease involving the reticuloendothelial system, total activities in the liver and spleen were estimated from the anteroposterior colour dot scan, and both liver and spleen blood flow were measured by methods independent of reticuloendothelial cell function. The results showed that the main factor causing increased uptake of colloid by the spleen in these diseases was an increased blood flow in the spleen relative to that in the liver. ImagesFIG. 1FIG. 5 PMID:5386628

  4. Induced pluripotent stem cell–derived hepatocytes have the functional and proliferative capabilities needed for liver regeneration in mice

    PubMed Central

    Espejel, Silvia; Roll, Garrett R.; McLaughlin, K. John; Lee, Andrew Y.; Zhang, Jenny Y.; Laird, Diana J.; Okita, Keisuke; Yamanaka, Shinya; Willenbring, Holger

    2010-01-01

    The ability to generate induced pluripotent stem (iPS) cells from a patient’s somatic cells has provided a foundation for organ regeneration without the need for immune suppression. However, it has not been established that the differentiated progeny of iPS cells can effectively reverse failure of a vital organ. Here, we examined whether iPS cell–derived hepatocytes have both the functional and proliferative capabilities needed for liver regeneration in mice with fumarylacetoacetate hydrolase deficiency. To avoid biases resulting from random genomic integration, we used iPS cells generated without viruses. To exclude compensation by hepatocytes not derived from iPS cells, we generated chimeric mice in which all hepatocytes were iPS cell derived. In vivo analyses showed that iPS cells were intrinsically able to differentiate into fully mature hepatocytes that provided full liver function. The iPS cell–derived hepatocytes also replicated the unique proliferative capabilities of normal hepatocytes and were able to regenerate the liver after transplantation and two-thirds partial hepatectomy. Thus, our results establish the feasibility of using iPS cells generated in a clinically acceptable fashion for rapid and stable liver regeneration. PMID:20739754

  5. Liver toxicity of thioacetamide is increased by hepatocellular iron overload.

    PubMed

    Ackerman, Zvi; Pappo, Orit; Link, Gabriela; Glazer, Maya; Grozovski, Maria

    2015-02-01

    An increase in hepatic iron concentration might exacerbate liver injury. However, it is unknown whether hepatic iron overload may exacerbate acute liver injury from various toxins. Therefore, we evaluated how manipulations to increase hepatic iron concentration affected the extent of acute liver injury from thioacetamide. In this study, we used rats with either "normal" or increased hepatic iron concentration. Iron overload was induced by either providing excess iron in the diet or by injecting iron subcutaneously. Both routes of providing excess iron induced an increase in hepatic iron overload. Meanwhile, the subcutaneous route induced both hepatocellular and sinusoidal cell iron deposition; the oral route induced lesser degree of hepatic iron concentration and only hepatocellular iron overload. Thioacetamide administration to the rats with "normal" hepatic iron concentration induced hepatic cell necrosis and apoptosis associated with a remarkable increase in serum aminotransaminases and depletion of hepatic glutathione and other antioxidative indices. Thioacetamide administration to the iron-overloaded rats exacerbated the extent of liver injury only in the rats orally induced with iron overload. In the rats subcutaneously induced with iron overload, the extent of liver injury from thioacetamide was not different from that observed in the rats with "normal" iron overload. It was concluded that the outcome of thioacetamide-induced acute liver injury may depend on both the level of hepatic iron concentration and on the cellular distribution of iron. While isolated hepatocellular iron overload may exacerbate thioacetamide-induced acute liver injury, a combined hepatocellular and sinusoidal cell iron deposition, even at high hepatic iron concentration, had no such an effect. PMID:25161090

  6. Loss of hepatocyte EGFR has no effect alone but exacerbates carbon tetrachloride-induced liver injury and impairs regeneration in hepatocyte Met-deficient mice

    PubMed Central

    Zhang, Xiuqi; Stevenson, Mary C.; Threadgill, David W.; Russell, William E.

    2014-01-01

    The role(s) of the epidermal growth factor receptor (EGFR) in hepatocytes is unknown. We generated a murine hepatocyte specific-EGFR knockout (KO) model to evaluate how loss of hepatocellular EGFR expression affects processes such as EGF clearance, circulating EGF concentrations, and liver regeneration following 70% resection or CCl4-induced centrilobular injury. We were able to disrupt EGFR expression effectively in hepatocytes and showed that the ability of EGF and heregulin (HRG) to phosphorylate EGFR and ERBB3, respectively, required EGFR. Loss of hepatocellular EGFR impaired clearance of exogenous EGF from the portal circulation but paradoxically resulted in reduced circulating levels of endogenous EGF. This was associated with decreased submandibular salivary gland production of EGF. EGFR disruption did not result in increased expression of other ERBB proteins or Met, except in neonatal mice. Liver regeneration following 70% hepatectomy revealed a mild phenotype, with no change in cyclin D1 expression and slight differences in cyclin A expression compared with controls. Peak 5-bromo-2′-deoxyuridine labeling was shifted from 36 to 48 h. Centrilobular damage and regenerative response induced by carbon tetrachloride (CCl4) were identical in the KO and wild-type mice. In contrast, loss of Met increased CCl4-induced necrosis and delayed regeneration. Although loss of hepatocellular EGFR alone did not have an effect in this model, EGFR-Met double KOs displayed enhanced necrosis and delayed liver regeneration compared with Met KOs alone. This suggests that EGFR and Met may partially compensate for the loss of the other, although other compensatory mechanisms can be envisioned. PMID:25414100

  7. Does arsenic exposure increase the risk for liver cancer?

    PubMed

    Chiu, Hui-Fen; Ho, Shu-Chen; Wang, Li-Yu; Wu, Trong-Neng; Yang, Chun-Yuh

    2004-10-01

    Arsenic has been well documented as the major risk factor for development of blackfoot disease (BFD), a unique peripheral vascular disease that was once endemic to the southwestern coast of Taiwan, where residents imbibed artesian well water containing high concentrations of arsenic for more than 50yr. Long-term arsenic exposure has also been reported to be associated with increased incidence of liver cancer in a dose-responsive manner. A tap-water supply system was implemented in the early 1960s in the BFD endemic areas. Artesian well water was no longer used for drinking and cooking after the mid-1970s. The objective of this study was to examine whether liver cancer mortality rates were altered after the consumption of high-arsenic artesian well water ceased and, if so, when the reduction occurred. Standardized mortality ratios (SMRs) for liver cancer were calculated for the BFD endemic area for the years 1971-2000. Cumulative-sum techniques were used to detect the occurrence of changes in the SMRs. The study results show that mortality from liver cancer in females declined starting 9yr after the cessation of consumption of high-arsenic artesian well water. However, data show fluctuations in male liver cancer mortality rates. Based on the reversibility criterion, the association between arsenic exposure and liver cancer mortality is likely to be causal for females but not in males.

  8. Appendectomy correlates with increased risk of pyogenic liver abscess

    PubMed Central

    Liao, Kuan-Fu; Lai, Shih-Wei; Lin, Cheng-Li; Chien, Sou-Hsin

    2016-01-01

    Abstract Little is known on the association between appendectomy and pyogenic liver abscess. The objective of this study was to investigate the association between appendectomy and the risk of pyogenic liver abscess in Taiwan. This population-based retrospective cohort study was conducted using the hospitalization dataset of the Taiwan National Health Insurance Program. There were 212,530 subjects age 20 to 84 years with newly diagnosed appendectomy as the appendectomy group since 1998 to 2010, and 850,099 randomly selected subjects without appendectomy as the nonappendectomy group. Both appendectomy and nonappendectomy groups were matched with sex, age, comorbidities, and index year of diagnosing appendectomy. The incidence of pyogenic liver abscess at the end of 2011 was estimated in both groups. The multivariable Cox proportional hazards regression model was applied to investigate the hazard ratio (HR) and 95% confidence interval (CI) for risk of pyogenic liver abscess associated with appendectomy and other comorbidities including alcoholism, biliary stone, chronic kidney disease, chronic liver diseases, and diabetes mellitus. The overall incidence of pyogenic liver abscess was 1.73-fold greater in the appendectomy group than that in the nonappendectomy group (3.85 vs 2.22 per 10,000 person-years, 95% CI 1.71, 1.76). The multivariable regression analysis disclosed that the adjusted HR of pyogenic liver abscess was 1.77 for the appendectomy group (95% CI 1.59, 1.97), when compared with the nonappendectomy group. Appendectomy is associated with increased hazard of pyogenic liver abscess. Further studies remain necessary to confirm our findings. PMID:27368018

  9. Establishment and primary clinical application of competitive inhibition for measurement of augmenter of liver regeneration.

    PubMed

    Wang, Na; Sun, Hang; Tang, Lin; Deng, Jianchuan; Luo, Ya; Guo, Hui; Liu, Qi

    2014-01-01

    The aim of the present study was to establish a quantitative method for the measurement of serum human augmenter of liver regeneration (hALR) using competitive inhibition that is applicable in the clinic. A monoclonal antibody to hALR was used as the primary antibody and the pure hALR protein was used as a standard for competition with Eu(3+)-labeled hALR (Eu(3+)-hALR) to plot a standard curve. Serum samples from 90 patients with various liver diseases due to hepatitis B virus (HBV) infection were used for a competitive reaction with Eu(3+)-hALR. A regression analysis of the results was performed using the standard curve to calculate the serum concentration of hALR. The minimum detectable value using direct competitive measurement established by Eu(3+)-hALR was 1 ng/ml, with a positive linear correlation within the range of 200 ng/ml. In the sera of the 90 patients, the hALR level in the severe hepatitis group was the highest, followed by that in the acute hepatitis group. The serum hALR levels in the cirrhosis and chronic hepatitis groups were significantly higher compared with those in the normal control groups (P<0.01). The direct competitive measurement method of serum hALR established in the present study has high sensitivity, specificity, stability and reliability, meets clinical requirements and may be used as potential index in clinical tests.

  10. Ischaemic Preconditioning and Intermittent Clamping Does not Influence Mediators of Liver Regeneration in a Human Liver Sinusoidal Endothelial Cell Model of Ischaemia-Reperfusion Injury

    PubMed Central

    Gomez, Dhanwant; Burn, J.. Lance; Graham, Ann; Homer-Vanniasinkam, Shervanthi; Prasad, K.. Rajendra

    2012-01-01

    Background The role of surgical technique on liver regeneration following surgery remains inconclusive. The aim of the study was to assess the effect of ischaemic preconditioning (IPC) and intermittent clamping (IC) on mediators of regeneration produced by human liver sinusoidal endothelial cells (SECs), using an in vitro hypoxia-reoxygenation model to mimic ischaemia-reperfusion injury (IRI). Methods Following extraction from samples obtained from liver resection (n = 5), confluent culture flasks of SECs were subjected to IRI (1 hour hypoxia + 1 hour reoxygenation), IPC prior to IRI (10 minutes hypoxia + 10 minutes reoxygenation + 1 hour hypoxia + 1 hour reoxygenation), IC (15 minutes hypoxia + 5 minutes reoxygenation x 3 + 1 hour reoxygenation) and compared to controls. The production of various mediators was determined over 48 hours. Results Interleukin (IL)-6, IL-8, granulocyte-colony stimulating factor (G-CSF) and hepatocyte growth factor (HGF) were produced by SECs. Both IPC and IC did not significantly influence the profile of IL-6, IL-8, G-CSF and HGF by SECs compared to IRI over the study period. Conclusion IPC and IC did not influence the production of pro-regenerative mediators in a SECs model of IRI. The role of surgical technique on liver regeneration remains to be determined.

  11. Hepatoprotectant ursodeoxycholyl lysophosphatidylethanolamide increasing phosphatidylcholine levels as a potential therapy of acute liver injury.

    PubMed

    Chamulitrat, Walee; Zhang, Wujuan; Xu, Weihong; Pathil, Anita; Setchell, Kenneth; Stremmel, Wolfgang

    2012-01-01

    It has been long known that hepatic synthesis of phosphatidylcholine (PC) is depressed during acute such as carbon tetrachloride-induced liver injury. Anti-hepatotoxic properties of PC as liposomes have been recognized for treatment of acute liver damage. Ursodeoxycholate (UDCA) is a known hepatoprotectant in stabilizing cellular membrane. For therapeutic management of liver injury, we coupled UDCA with a phospholipid known as ursodeoxycholyl lysophosphatidylethanolamide (UDCA-LPE). UDCA-LPE has been shown to first-in-class hepatoprotectant being superior to UDCA or PC. It inhibits mitochondrial damage and apoptosis, elicits survival signaling pathway, and promotes regeneration of hepatocytes. We herein report that a unique contribution of UDCA-LPE in increasing concentrations of PC in vitro and in vivo. UDCA-LPE-treated hepatocytes contained significantly increased PC levels. UDCA-LPE underwent the hydrolysis to LPE which was not the precursor of the increased PC. The levels of PC in the liver and blood were increased rapidly after intraperitoneally administration UDCA-LPE, and were found to be sustained even after 24 h. Among PC synthesis genes tested, UDCA-LPE treatment of mouse hepatocytes increased transcription of CDP-diacylglycerol synthase 1 which is an enzyme catalyzing phosphatidic acid to generate intermediates for PC synthesis. Thus, UDCA-LPE as a hepatoprotectant was able to induce synthesis of protective PC which would supplement for the loss of PC occurring during acute liver injury. This property has placed UDCA-LPE as a candidate agent for therapy of acute hepatotoxicity such as acetaminophen poisoning. PMID:22363296

  12. Impaired liver regeneration in Ldlr−/− mice is associated with an altered hepatic profile of cytokines, growth factors and lipids

    PubMed Central

    Pauta, Montse; Rotllan, Noemi; Vales, Frances; Allen, Ryan M.; Ford, David A.; Marí, Montserrat; Jiménez, Wladimiro; Baldán, Ángel

    2014-01-01

    Background & Aims It is widely recognized that in the early stages of liver regeneration after partial hepatectomy the hepatocytes accumulate a significant amount of lipids. The functional meaning of this transient steatosis and its effect on hepatocellular proliferation are not well defined. In addition, the basic mechanisms of this lipid accumulation are not well understood although some studies suggest the participation of the Low Density Lipoprotein Receptor (Ldlr). Methods To address these questions we studied the process of liver regeneration in Ldlr null mice and wild-type mice following 75% partial hepatectomy. Results Ldlr deficiency was associated with a significant decrease in serum albumin concentration, during early stages of liver regeneration, and a delayed hepatic regeneration. Remnant livers of Ldlr−/− showed a time-shifted expression of interleukin-6 (IL-6) and a defective activation of tumor necrosis factor-α (TNFα) and hepatocyte growth factor (HGF) expression in early phases of liver regeneration. Unexpectedly, Ldlr−/− showed no significant differences in the content of lipid droplets after partial hepatectomy compared to wild-type mice. However, lipidomic analysis of the regenerating liver from Ldlr−/− revealed a lipid profile compatible with liver quiescence: high content of cholesterol esters and ceramide, and low levels of phosphatidylcholine. Conclusion Ldlr deficiency is associated with significant changes in the hepatic lipidome that affect cytokine-growth factor signaling and impair liver regeneration. These results suggest that the analysis of the hepatic lipidome may help to predict the success of liver regeneration in the clinical environment, specifically in the context of pre-existing liver steatosis. PMID:23712050

  13. Transient expression of laminin {alpha}1 chain in regenerating murine liver: Restricted localization of laminin chains and nidogen-1

    SciTech Connect

    Kikkawa, Yamato . E-mail: yamato@sapmed.ac.jp; Mochizuki, Yoichi; Miner, Jeffrey H.; Mitaka, Toshihiro

    2005-04-15

    Most interstitia between epithelial and endothelial cells contain basal laminae (BLs), as defined by electron microscopy. However, in liver, the sinusoidal interstitium (called space of Disse) between hepatocytes and sinusoidal endothelial cells (SECs) lacks BLs. Because laminins are major components of BLs throughout the body, whether laminins exist in sinusoids has been a controversial issue. Despite recent advances, the distribution and expression of laminin chains have not been well defined in mammalian liver. Here, using a panel of antibodies, we examined laminins in normal and regenerating mouse livers. Of {alpha} chains, {alpha}5 was widely observed in all BLs except for sinusoids, while the other {alpha} chains were variously expressed in Glisson's sheath and central veins. Laminin {gamma}1 was also distributed to all BLs except for sinusoids. Although the {beta}2 chain was observed in all BLs and sinusoids, the expression of {beta}1 chain was restricted to Glisson's sheath. Detailed analysis of regenerating liver revealed that {alpha}1 and {gamma}1 chains appeared in sinusoids and were produced by stellate cells. The staining of {alpha}1 and {gamma}1 chains reached its maximum intensity at 6 days after two-thirds partial hepatectomy (PHx). Moreover, in vitro studies showed that {alpha}1-containing laminin promoted spreading of sinusoidal endothelial cells (SECs) isolated from normal liver, but not other hepatic cells. In addition, SECs isolated from regenerating liver elongated pseudopodia on {alpha}1-containing laminin more so than did cells from normal liver. The transient expression of laminin {alpha}1 may promote formation of sinusoids after PHx.

  14. Chronic exercise increases insulin binding in muscles but not liver

    SciTech Connect

    Bonen, A.; Clune, P.A.; Tan, M.H.

    1986-08-01

    It has been postulated that the improved glucose tolerance provoked by chronic exercise is primarily attributable to increased insulin binding in skeletal muscle. Therefore, the authors investigated the effects of progressively increased training (6 wk) on insulin binding by five hindlimb skeletal muscles and in liver. In the trained animals serum insulin levels at rest were lower either in a fed or fasted state and after an oral glucose tolerance test. Twenty-four hours after the last exercise bout sections of the liver, soleus (S), plantaris (P), extensor digitorum longus (EDL), and red (RG) and white gastrocnemius (WG) muscles were pooled from four to six rats. Insulin binding to plasma membranes increased in S, P, and EDL but not in WG or in liver. There were insulin binding differences among muscles. Comparison of rank orders of insulin binding data with published glucose transport data for the same muscles revealed that these parameters do not correspond well. In conclusion, insulin binding to muscle is shown to be heterogeneous and training can increase insulin binding to selected muscles but not liver.

  15. Human augmenter of liver regeneration: probing the catalytic mechanism of a flavin-dependent sulfhydryl oxidase.

    PubMed

    Schaefer-Ramadan, Stephanie; Gannon, Shawn A; Thorpe, Colin

    2013-11-19

    Augmenter of liver regeneration is a member of the ERV family of small flavin-dependent sulfhydryl oxidases that contain a redox-active CxxC disulfide bond in redox communication with the isoalloxazine ring of bound FAD. These enzymes catalyze the oxidation of thiol substrates with the reduction of molecular oxygen to hydrogen peroxide. This work studies the catalytic mechanism of the short, cytokine form of augmenter of liver regeneration (sfALR) using model thiol substrates of the enzyme. The redox potential of the proximal disulfide in sfALR was found to be approximately 57 mV more reducing than the flavin chromophore, in agreement with titration experiments. Rapid reaction studies show that dithiothreitol (DTT) generates a transient mixed disulfide intermediate with sfALR signaled by a weak charge-transfer interaction between the thiolate of C145 and the oxidized flavin. The subsequent transfer of reducing equivalents to the flavin ring is relatively slow, with a limiting apparent rate constant of 12.4 s(-1). However, reoxidation of the reduced flavin by molecular oxygen is even slower (2.3 s(-1) at air saturation) and thus largely limits turnover at 5 mM DTT. The nature of the charge-transfer complexes observed with DTT was explored using a range of simple monothiols to mimic the initial nucleophilic attack on the proximal disulfide. While β-mercaptoethanol is a very poor substrate of sfALR (∼0.3 min(-1) at 100 mM thiol), it rapidly generates a mixed disulfide intermediate allowing the thiolate of C145 to form a strong charge-transfer complex with the flavin. Unlike the other monothiols tested, glutathione is unable to form charge-transfer complexes and is an undetectable substrate of the oxidase. These data are rationalized on the basis of the stringent steric requirements for thiol-disulfide exchange reactions. The inability of the relatively bulky glutathione to attain the in-line geometry required for efficient disulfide exchange in sfALR may be

  16. Increased liver pathology in hepatitis C virus transgenic mice expressing the hepatitis B virus X protein

    SciTech Connect

    Keasler, Victor V.; Lerat, Herve; Madden, Charles R.; Finegold, Milton J.; McGarvey, Michael J.; Mohammed, Essam M.A.; Forbes, Stuart J.; Lemon, Stanley M.; Hadsell, Darryl L.; Grona, Shala J.; Hollinger, F. Blaine; Slagle, Betty L. . E-mail: bslagle@bcm.edu

    2006-04-10

    Transgenic mice expressing the full-length HCV coding sequence were crossed with mice that express the HBV X gene-encoded regulatory protein HBx (ATX mice) to test the hypothesis that HBx expression accelerates HCV-induced liver pathogenesis. At 16 months (mo) of age, hepatocellular carcinoma was identified in 21% of HCV/ATX mice, but in none of the single transgenic animals. Analysis of 8-mo animals revealed that, relative to HCV/WT mice, HCV/ATX mice had more severe steatosis, greater liver-to-body weight ratios, and a significant increase in the percentage of hepatocytes staining for proliferating cell nuclear antigen. Furthermore, primary hepatocytes from HCV, ATX, and HCV/ATX transgenic mice were more resistant to fas-mediated apoptosis than hepatocytes from nontransgenic littermates. These results indicate that HBx expression contributes to increased liver pathogenesis in HCV transgenic mice by a mechanism that involves an imbalance in hepatocyte death and regeneration within the context of severe steatosis.

  17. Expression and localization of augmenter of liver regeneration in human muscle tissue.

    PubMed

    Polimeno, Lorenzo; Pesetti, Barbara; Giorgio, Floriana; Moretti, Biagio; Resta, Leonardo; Rossi, Roberta; Annoscia, Emanuele; Patella, Vittorio; Notarnicola, Angela; Mallamaci, Rosanna; Francavilla, Antonio

    2009-08-01

    Mitochondrial DNA (mt-DNA) disorders and abnormal regulation of nuclear-derived proteins devoted to the cross-talk between the two cellular genomes have recently interested researchers in the field of neuromuscular diseases. We have identified, isolated and sequenced a new gene, augmenter of liver regeneration (ALR) that stimulates in vivo hepatocyte proliferation and up-regulates mt-DNA expression and ATP production. ALR protein (Alrp) is mainly located, in rat, in the mitochondrial inter-membrane space and its mRNA is particularly abundant in brain, muscle, testis and liver, tissues whose activity is mostly dependent on mitochondrial metabolism. Studies on rat Alrp sequence revealed the presence of homologous amino-acid sections into proteins derived from mouse, human, Drosophyla, plants and even DNA viruses. In this article, we evaluated ALR expression in normal human muscular tissues, both as protein and as mRNA. The data, obtained by molecular biology, immunohistochemistry and electron microscopy, demonstrated that: (i) Alrp and ALR mRNA are present in human muscular tissue; (ii) Alrp is particularly expressed in muscular fibres rich in mitochondria; (iii) Alrp is localized in the mitochondrial inter-membrane space or associated to mitochondrial cristae; and (iv) in subjects younger then 35 years of age, ALR mRNA expression is different between male and female subjects. In conclusion, the present data set Alrp, as a factor associated with mitochondria also in human tissue, call for future studies aimed at establishing Alrp as an important factor involved in the molecular events that trigger neuromuscular diseases.

  18. Expression and localization of augmenter of liver regeneration in human muscle tissue

    PubMed Central

    Lorenzo, Polimeno; Barbara, Pesetti; Floriana, Giorgio; Biagio, Moretti; Leonardo, Resta; Roberta, Rossi; Emanuele, Annoscia; Vittorio, Patella; Angela, Notarnicola; Rosanna, Mallamaci; Antonio, Francavilla

    2009-01-01

    Mitochondrial DNA (mt-DNA) disorders and abnormal regulation of nuclear-derived proteins devoted to the cross-talk between the two cellular genomes have recently interested researchers in the field of neuromuscular diseases. We have identified, isolated and sequenced a new gene, augmenter of liver regeneration (ALR) that stimulates in vivo hepatocyte proliferation and up-regulates mt-DNA expression and ATP production. ALR protein (Alrp) is mainly located, in rat, in the mitochondrial inter-membrane space and its mRNA is particularly abundant in brain, muscle, testis and liver, tissues whose activity is mostly dependent on mitochondrial metabolism. Studies on rat Alrp sequence revealed the presence of homologous amino-acid sections into proteins derived from mouse, human, Drosophyla, plants and even DNA viruses. In this article, we evaluated ALR expression in normal human muscular tissues, both as protein and as mRNA. The data, obtained by molecular biology, immunohistochemistry and electron microscopy, demonstrated that: (i) Alrp and ALR mRNA are present in human muscular tissue; (ii) Alrp is particularly expressed in muscular fibres rich in mitochondria; (iii) Alrp is localized in the mitochondrial inter-membrane space or associated to mitochondrial cristae; and (iv) in subjects younger then 35 years of age, ALR mRNA expression is different between male and female subjects. In conclusion, the present data set Alrp, as a factor associated with mitochondria also in human tissue, call for future studies aimed at establishing Alrp as an important factor involved in the molecular events that trigger neuromuscular diseases. PMID:19659900

  19. Cyclin-dependent kinase 1 (Cdk1) is essential for cell division and suppression of DNA re-replication but not for liver regeneration

    PubMed Central

    Diril, M. Kasim; Ratnacaram, Chandrahas Koumar; Padmakumar, V. C.; Wasser, Martin; Coppola, Vincenzo; Tessarollo, Lino; Kaldis, Philipp

    2012-01-01

    Cyclin-dependent kinase 1 (Cdk1) is an archetypical kinase and a central regulator that drives cells through G2 phase and mitosis. Knockouts of Cdk2, Cdk3, Cdk4, or Cdk6 have resulted in viable mice, but the in vivo functions of Cdk1 have not been fully explored in mammals. Here we have generated a conditional-knockout mouse model to study the functions of Cdk1 in vivo. Ablation of Cdk1 leads to arrest of embryonic development around the blastocyst stage. Interestingly, liver-specific deletion of Cdk1 is well tolerated, and liver regeneration after partial hepatectomy is not impaired, indicating that regeneration can be driven by cell growth without cell division. The loss of Cdk1 does not affect S phase progression but results in DNA re-replication because of an increase in Cdk2/cyclin A2 activity. Unlike other Cdks, loss of Cdk1 in the liver confers complete resistance against tumorigenesis induced by activated Ras and silencing of p53. PMID:22355113

  20. Cellular Origins of Regenerating Nodules and Malignancy in the FAH Model of Liver Injury after Bone Marrow Cell Transplantation

    PubMed Central

    Wang, Pei-Rong; Li, Yi

    2016-01-01

    In previous reports, we and other groups have shown that proliferating hepatocytes are formed by the fusion of donor hematopoietic cells with host hepatocytes in the Fah−/− model. Thus, it would be interesting to determine whether cell fusion occurs during malignancy. However, it is difficult to demonstrate such processes using this model. Therefore, we established a new strain to study the processes of regenerating nodules and malignancy and their origins. The FAH−/− mouse model was crossed with the ROSAnZ strain and their offspring was genotyped for FAH−/− and ROSAnZ mutations to create a new strain (Fah−/−-ROSAnZ). Using this strain as recipients, we performed bone marrow transplantation experiments. As a result, we could not demonstrate the presence of any epithelial cells except hepatocytes that were of donor origin in regenerating tissue, and no evidence of cell fusion was found in tumors. The hepatic malignancy was of host origin in these mice. There was higher expression of extracellular matrix proteins and more inflammatory cells in liver tumor nodules than in regenerating normal liver nodules. Hepatocytes generated by fusion with bone marrow cells did not form malignant tumors. Extracellular matrix and inflammatory cells had significantly accumulated in liver tumors. PMID:26962307

  1. Comment on "Post-wildfire logging hinders regeneration and increases fire risk".

    PubMed

    Newton, M; Fitzgerald, S; Rose, R R; Adams, P W; Tesch, S D; Sessions, J; Atzet, T; Powers, R F; Skinner, C

    2006-08-01

    Donato et al. (Brevia, 20 January 2006, p. 352) concluded that logging after wildfire kills natural regeneration and increases fire risk. We argue that their paper lacks adequate context and supporting information to be clearly interpreted by scientists, resource managers, policy-makers, and the public.

  2. Methods of Liver Stem Cell Therapy in Rodents as Models of Human Liver Regeneration in Hepatic Failure.

    PubMed

    Hashemi Goradel, Nasser; Darabi, Masoud; Shamsasenjan, Karim; Ejtehadifar, Mostafa; Zahedi, Sarah

    2015-09-01

    Cell therapy is a promising intervention for treating liver diseases and liver failure. Different animal models of human liver cell therapy have been developed in recent years. Rats and mice are the most commonly used liver failure models. In fact, rodent models of hepatic failure have shown significant improvement in liver function after cell infusion. With the advent of stem-cell technologies, it is now possible to re-programme adult somatic cells such as skin or hair-follicle cells from individual patients to stem-like cells and differentiate them into liver cells. Such regenerative stem cells are highly promising in the personalization of cell therapy. The present review article will summarize current approaches to liver stem cell therapy with rodent models. In addition, we discuss common cell tracking techniques and how tracking data help to direct liver cell therapy research in animal models of hepatic failure.

  3. [Liver and artificial liver].

    PubMed

    Chamuleau, R A

    1998-06-01

    Despite good results of orthotopic liver transplantation in patients with fulminant hepatic failure the need still exists for an effective and safe artificial liver, able to temporarily take over the complex liver function so as to bridge the gap with transplantation or regeneration. Attempts to develop non-biological artificial livers have failed, mostly when controlled clinical trials were performed. In the last decade several different types of bioartificial livers have been devised, in which the biocomponent consists of freshly isolated porcine hepatocytes or a human hepatoblastoma cell line. The majority use semipermeable hollow fibers known from artificial kidney devices. The liver cells may lie either inside or outside the lumen of these fibers. In vitro analysis of liver function and animal experimental work showing that the bioartificial liver increases survival justify clinical application. Bioartificial livers are connected to patients extracorporeally by means of plasmapheresis circuit for periods of about 6 hours. In different trials about 40 patients with severe liver failure have been treated. No important adverse effects have not been reported in these phase I trials. Results of controlled studies are urgently needed. As long as no satisfactory immortalised human liver cell line with good function is available, porcine hepatocytes will remain the first choice, provided transmission of porcine pathogens to man is prevented. PMID:9752034

  4. Increased sphingosine-1-phosphate improves muscle regeneration in acutely injured mdx mice

    PubMed Central

    2013-01-01

    Background Presently, there is no effective treatment for the lethal muscle wasting disease Duchenne muscular dystrophy (DMD). Here we show that increased sphingosine-1-phoshate (S1P) through direct injection or via the administration of the small molecule 2-acetyl-4(5)-tetrahydroxybutyl imidazole (THI), an S1P lyase inhibitor, has beneficial effects in acutely injured dystrophic muscles of mdx mice. Methods We treated mdx mice with and without acute injury and characterized the histopathological and functional effects of increasing S1P levels. We also tested exogenous and direct administration of S1P on mdx muscles to examine the molecular pathways under which S1P promotes regeneration in dystrophic muscles. Results Short-term treatment with THI significantly increased muscle fiber size and extensor digitorum longus (EDL) muscle specific force in acutely injured mdx limb muscles. In addition, the accumulation of fibrosis and fat deposition, hallmarks of DMD pathology and impaired muscle regeneration, were lower in the injured muscles of THI-treated mdx mice. Furthermore, increased muscle force was observed in uninjured EDL muscles with a longer-term treatment of THI. Such regenerative effects were linked to the response of myogenic cells, since intramuscular injection of S1P increased the number of Myf5nlacz/+ positive myogenic cells and newly regenerated myofibers in injured mdx muscles. Intramuscular injection of biotinylated-S1P localized to muscle fibers, including newly regenerated fibers, which also stained positive for S1P receptor 1 (S1PR1). Importantly, plasma membrane and perinuclear localization of phosphorylated S1PR1 was observed in regenerating muscle fibers of mdx muscles. Intramuscular increases of S1P levels, S1PR1 and phosphorylated ribosomal protein S6 (P-rpS6), and elevated EDL muscle specific force, suggest S1P promoted the upregulation of anabolic pathways that mediate skeletal muscle mass and function. Conclusions These data show that S1P is

  5. Proliferation of the intestinal epithelium and of the regenerating liver of rats with epidermal growth factor deficiency

    SciTech Connect

    Ivashchenko, Yu.D.; Gut, I.T.; Osipova, L.A.; Garmanchuk, L.V.; Khranovskaya, L.N.; Bykorez, A.I.

    1986-09-01

    The presence of specific receptors for epidermal growth factor (EGF) in hepatocytes and enterocytes, changes in their number during the period of postresection regeneration of the liver, and also the inexplicably high concentrations of this powerful growth factor in the saliva determined the main purpose of this investigation, which was to study the effect of EGF deficiency, produced by submandibular sialadenectomy, on proliferation of the intestinal and hepatic epithelium during postresection regeneration of these organs. The experiments were carried out on rats that received an intraperitoneal injection of /sup 3/H-thymidine. The specific activity of /sup 125/I-EGF was 12,000 cpm/ng. The EGF concentration in the rats' blood serum, saliva, and urine was determined by radioimmunoassay. Bound /sup 125/I-EGF was precipitated. Results indicate that EGF is a regulatory factor which modifies proliferation.

  6. Ethynylestradiol increases expression and activity of rat liver MRP3.

    PubMed

    Ruiz, María L; Villanueva, Silvina S M; Luquita, Marcelo G; Vore, Mary; Mottino, Aldo D; Catania, Viviana A

    2006-06-01

    We evaluated the effect of ethynylestradiol (EE) administration (5 mg/kg b.wt. s.c., for 5 consecutive days) on the expression and activity of multidrug resistance-associated protein 3 (Mrp3) in rats. Western blotting analysis revealed decreased Mrp2 (-41%) and increased Mrp3 (+200%) expression by EE. To determine the functional impact of up-regulation of Mrp3 versus Mrp2, we measured the excretion of acetaminophen glucuronide (APAP-glu), a common substrate for both transporters, into bile and perfusate in the recirculating isolated perfused liver (IPL) model. APAP-glu was generated endogenously from acetaminophen (APAP), which was administered as a tracer dose (2 micromol/ml) into the perfusate. Biliary excretion of APAP-glu after 60 min of perfusion was reduced in EE-treated rats (-80%). In contrast, excretion into the perfusate was increased by EE (+45%). Liver content of APAP-glu at the end of the experiment was reduced by 36% in the EE group. The total amount of glucuronide remained the same in both groups. Taken together, these results indicate that up-regulation of Mrp3 led to an exacerbated basolateral versus canalicular excretion of conjugated APAP in IPL. We conclude that induced expression of basolateral Mrp3 by EE may represent a compensatory mechanism to prevent intracellular accumulation of common Mrp substrates, either endogenous or exogenous, due to reduced expression and activity of apical Mrp2. PMID:16554369

  7. The sympathetic nervous system promotes carbon tetrachloride-induced liver cirrhosis in rats by suppressing apoptosis and enhancing the growth kinetics of regenerating hepatocytes.

    PubMed

    Hamasaki, K; Nakashima, M; Naito, S; Akiyama, Y; Ohtsuru, A; Hamanaka, Y; Hsu, C T; Ito, M; Sekine, I

    2001-02-01

    Norepinephrine is considered to possess potent anti-apoptotic action in regenerating hepatocytes. To clarify the role of the sympathetic nervous system in apoptosis that occurs in chronic liver damage and following the promotion of liver cirrhosis, we studied a carbon tetrachloride (CCl4)-induced liver injury model, using spontaneously hypertensive rats (SHR), Wistar-Kyoto rats (WKY), and chemically sympathectomized WKY. At 24 h after CCl4 administration. acute damage, characterized by vacuolated hepatocytes in the centrilobular zone, was greater in SHR than in WKY. This vacuolated change in WKY hepatocytes was significantly reduced by chemical sympathectomy with 6-hydroxydopamine (6-OHDA). After 48 h, the acute damage was dramatically improved in each animal, without significant differences between the three groups. In chronic damage after weekly repetition of CCl4 treatment for 4 weeks, fibrosis was evident in SHR, while in the other groups there was only scant fibrosis in the centrilobular zone. After 8 weeks' repetition of CCl4, liver cirrhosis was seen only in SHR. The incidence of apoptotic cells in areas of both acute and chronic damage in WKY, detected by terminal deoxynucleotidyl transferase-dUTP nick end labeling, was significantly increased in comparison with that in SHR, and was further increased by 6-OHDA pretreatment. In contrast, there was significantly greater enhancement of the growth of hepatocytes in SHR than in WKY in both acute and chronic damage. Moreover. hepatocyte growth kinetics in WKY was significantly inhibited after sympathectomy in acute injury, as evidenced by immunohistochemistry for proliferating cell nuclear antigen (PCNA). In vitro, the amount of hepatocellular apoptosis induced by transforming growth factor-beta1 was significantly decreased by incubation with norepinephrine. These findings suggest that the anti-apoptotic effect of the sympathetic nervous system increases cell growth kinetics and promotes liver cirrhosis in this

  8. Differential Expression of SWI/SNF Chromatin Remodeler Subunits Brahma and Brahma-Related Gene During Drug-Induced Liver Injury and Regeneration in Mouse Model.

    PubMed

    Sinha, Sonal; Verma, Sudhir; Chaturvedi, Madan M

    2016-08-01

    The chromatin remodeling activity of mammalian SWI/SNF complex is carried out by either Brahma (BRM) or Brahma-related gene (BRG-1). The BRG-1 regulates genes involved in cell proliferation, whereas BRM is associated with cell differentiation, and arrest of cell growth. Global modifications of histones and expression of genes of chromatin-remodeling subunits have not been studied in in vivo model systems. In the present study, we investigate epigenetic modifications of histones and the expression of genes in thioacetamide (TAA)-induced liver injury and regeneration in a mouse model. In the present study, we report that hepatocyte proliferation and H3S10 phosphorylation occur during 60 to 72 h post TAA treatment in mice. Furthermore, there was change in the H3K9 acetylation and H3K9 trimethylation pattern with respect to liver injury and regeneration phase. Looking into the expression pattern of Brg-1 and Brm, it is evident that they contribute substantially to the process of liver regeneration. The SWI/SNF remodeler might contain BRG-1 as its ATPase subunit during injury phase. Whereas, BRM-associated SWI/SNF remodeler might probably be predominant during decline of injury phase and initiation of regeneration phase. Furthermore, during the regeneration phase, BRG-1-containing remodeler again predominates. Considering all these observations, the present study depicts an interplay between chromatin interacting machineries in different phases of thioacetamide-induced liver injury and regeneration.

  9. Risk Factors Associated with Increased Morbidity in Living Liver Donation

    PubMed Central

    Candido, Helry L.; da Fonseca, Eduardo A.; Feier, Flávia H.; Pugliese, Renata; Benavides, Marcel A.; Silva, Enis D.; Gordon, Karina; de Abreu, Marcelo Gama; Canet, Jaume; Chapchap, Paulo; Neto, Joao Seda

    2015-01-01

    Living donor liver donation (LDLD) is an alternative to cadaveric liver donation. We aimed at identifying risk factors and developing a score for prediction of postoperative complications (POCs) after LDLD in donors. This is a retrospective cohort study in 688 donors between June 1995 and February 2014 at Hospital Sírio-Libanês and A.C. Camargo Cancer Center, in São Paulo, Brazil. Primary outcome was POC graded ≥III according to the Clavien-Dindo classification. Left lateral segment (LLS), left lobe (LL), and right lobe resections (RL) were conducted in 492 (71.4%), 109 (15.8%), and 87 (12.6%) donors, respectively. In total, 43 (6.2%) developed POCs, which were more common after RL than LLS and LL (14/87 (16.1%) versus 23/492 (4.5%) and 6/109 (5.5%), resp., p < 0.001). Multivariate analysis showed that RL resection (OR: 2.81, 95% CI: 1.32 to 3.01; p = 0.008), smoking status (OR: 3.2, 95% CI: 1.35 to 7.56; p = 0.012), and blood transfusion (OR: 3.15, 95% CI: 1.45 to 6.84; p = 0.004) were independently associated with POCs. RL resection, intraoperative blood transfusion, and smoking were associated with increased risk for POCs in donors. PMID:26788361

  10. Increased prevalence of intestinal inflammation in patients with liver cirrhosis

    PubMed Central

    Saitoh, Osamu; Sugi, Kazunori; Kojima, Keishi; Matsumoto, Hisashi; Nakagawa, Ken; Kayazawa, Masanobu; Tanaka, Seigou; Teranishi, Tsutomu; Hirata, Ichiro; Katsu, Ken-ichi

    1999-01-01

    AIM: To investigate the pathophysiology of the digestive tract in patients with liver cirrhosis. METHODS: In 42 cirrhotic patients and 20 control subjects, the following fecal proteins were measured by enzyme-linked immunosorbent assay: albumin (Alb), transferrin (Tf), and α1-antitrypsin (α1-AT) as a marker for intestinal protein loss, hemoglobin (Hb) for bleeding, PMN-elastase for intestinal inflammation, and secretory IgA for intestinal immunity. RESULTS: The fecal concentrations of Hb, Alb, Tf, α1-AT, an d PMN-elastase were increased in 13 (31%), 8 (19%), 10 (24%), 6 (14%), and 11 (26%) cases among 42 patients, respectively. Fecal concentration of secretory IgA was decreased in 7 (17%) of 42 patients. However, these fecal concentrations were not related to the severity or etiology of liver cirrhosis. The serum Alb level was significantly decreased in patients with intestinal protein loss compared to that in patients without intestinal protein loss. CONCLUSION: These findings suggest that: ① besides the well-known pathological conditions, such as bleeding and protein loss, intestinal inflammation and decreased intestinal immunity are found in cirrhotic patients; ② intestinal protein loss contributes to hypoalbuminemia in cirrhotic patients, and ③ intestinal inflammation should not be over looked in cirrhotic patients, since it may contribute to or cause intestinal protein loss and other various path ological conditions. PMID:11819475

  11. Preexposure to Olive Oil Polyphenols Extract Increases Oxidative Load and Improves Liver Mass Restoration after Hepatectomy in Mice via Stress-Sensitive Genes

    PubMed Central

    Marinić, Jelena; Broznić, Dalibor; Milin, Čedomila

    2016-01-01

    Polyphenols can act as oxidants in some conditions, inducing redox-sensitive genes. We investigated the effect of preexposure to the olive oil polyphenols extract (PFE) on time-dependent changes in the hepatic oxidative state in a model of liver regeneration—a process in which oxidative stress associated with the metabolic overload accounts for the early events that contribute to the onset of liver self-repair. Liver regeneration was induced by one-third hepatectomy in mice. Prior to hepatectomy, mice were intraperitoneally given either PFE (50 mg/kg body weight) or saline for seven consecutive days, while respective controls received vehicle alone. Redox state-regulating enzymes and thiol proteins along with the mRNA levels of Nrf2 gene and its targets γ-glutamylcysteine synthetase and heme oxygenase-1 were determined at different time intervals after hepatectomy. The liver mass restoration was calculated to assess hepatic regeneration. The resulting data demonstrate the effectiveness of preexposure to PFE in stimulating liver regeneration in a model of a small tissue loss which may be ascribed to the transient increase in oxidant load during the first hours after hepatectomy and associated induction of stress response gene-profiles under the control of Nrf2. PMID:26925195

  12. Stem cells in liver regeneration, fibrosis and cancer: the good, the bad and the ugly.

    PubMed

    Alison, M R; Islam, S; Lim, S

    2009-01-01

    The worldwide shortage of donor livers to transplant end stage liver disease patients has prompted the search for alternative cell therapies for intractable liver diseases, such as acute liver failure, cirrhosis and hepatocellular carcinoma (HCC). Under normal circumstances the liver undergoes a low rate of hepatocyte 'wear and tear' renewal, but can mount a brisk regenerative response to the acute loss of two-thirds or more of the parenchymal mass. A body of evidence favours placement of a stem cell niche in the periportal regions, although the identity of such stem cells in rodents and man is far from clear. In animal models of liver disease, adopting strategies to provide a selective advantage for transplanted hepatocytes has proved highly effective in repopulating recipient livers, but the poor success of today's hepatocyte transplants can be attributed to the lack of a clinically applicable procedure to force a similar repopulation of the human liver. The activation of bipotential hepatic progenitor cells (HPCs) is clearly vital for survival in many cases of acute liver failure, and the signals that promote such reactions are being elucidated. Bone marrow cells (BMCs) make, at best, a trivial contribution to hepatocyte replacement after damage, but other BMCs contribute to the hepatic collagen-producing cell population, resulting in fibrotic disease; paradoxically, BMC transplantation may help alleviate established fibrotic disease. HCC may have its origins in either hepatocytes or HPCs, and HCCs, like other solid tumours appear to be sustained by a minority population of cancer stem cells. PMID:18991329

  13. Both coding exons of the c-myc gene contribute to its posttranscriptional regulation in the quiescent liver and regenerating liver and after protein synthesis inhibition.

    PubMed Central

    Lavenu, A; Pistoi, S; Pournin, S; Babinet, C; Morello, D

    1995-01-01

    In vivo, the steady-state level of c-myc mRNA is mainly controlled by posttranscriptional mechanisms. Using a panel of transgenic mice in which various versions of the human c-myc proto-oncogene were under the control of major histocompatibility complex H-2Kb class I regulatory sequences, we have shown that the 5' and the 3' noncoding sequences are dispensable for obtaining a regulated expression of the transgene in adult quiescent tissues, at the start of liver regeneration, and after inhibition of protein synthesis. These results indicated that the coding sequences were sufficient to ensure a regulated c-myc expression. In the present study, we have pursued this analysis with transgenes containing one or the other of the two c-myc coding exons either alone or in association with the c-myc 3' untranslated region. We demonstrate that each of the exons contains determinants which control c-myc mRNA expression. Moreover, we show that in the liver, c-myc exon 2 sequences are able to down-regulate an otherwise stable H-2K mRNA when embedded within it and to induce its transient accumulation after cycloheximide treatment and soon after liver ablation. Finally, the use of transgenes with different coding capacities has allowed us to postulate that the primary mRNA sequence itself and not c-Myc peptides is an important component of c-myc posttranscriptional regulation. PMID:7623834

  14. Increasing the effectiveness of native forest regeneration and reforestation: towards climate-change adaptation in drylands

    NASA Astrophysics Data System (ADS)

    Branquinho, Cristina; Príncipe, Adriana; Nunes, Alice; Kobel, Melanie; Soares, Cristina; Pinho, Pedro

    2016-04-01

    The recent expansion of the semiarid climate to all the region of the south of Portugal and the growing impact of climate change demands local adaptation. The growth of the native forest represents a strategy at the ecosystem level to adapt to climate change since it increases resilience and increases also de delivery of ecosystem services such as the increment of organic matter in the soil, carbon and nitrogen, biodiversity, water infiltration, etc. Moreover decreases susceptibility to desertification. For that reason, large areas have been reforested in the south of Portugal with the native species holm oak and cork oak but with a low rate of effectiveness. Our goal in this work is to show how the cost-benefit relation of the actions intended to expand the forest of the Portuguese semiarid can be lowered by taking into account the microclimatic conditions and high spatial resolution management. The potential of forest regeneration was modelled at the local and regional level in the semiarid area using information concerning the Potential Solar Radiation. This model gives us the rate of native forest regeneration after a disturbance with high spatial resolution. Based on this model the territory was classified in: i) easy regeneration areas; ii) areas with the need of assisted reforestation, using methods that increase water and soil conservation; iii) areas of difficult reforestation because of the costs. Additionally a summary of the success of reforestations was made in the historical semiarid since the 60s based on the evaluation of a series of case studies, where we quantified the ecosystem services currently delivered by the reforested ecosystems. Acknowledgement: Programa Adapt: financed by EEA Grants and Fundo Português de Carbono

  15. Genes Inducing iPS Phenotype Play a Role in Hepatocyte Survival and Proliferation in vitro and Liver Regeneration in vivo

    PubMed Central

    Bhave, Vishakha S.; Paranjpe, Shirish; Bowen, William C.; Donthamsetty, Shashikiran; Bell, Aaron W.; Khillan, Jaspal S.; Michalopoulos, George K.

    2011-01-01

    Reprogramming factors have been used to induce pluripotent stem cells as an alternative to somatic cell nuclear transfer technology in studies targeting disease models and regenerative medicine. The neuronal repressor REST maintains self renewal and pluripotency in mouse embryonic stem cells by maintaining the expression Oct3/4, Nanog, and cMyc. We report that primary hepatocytes express REST and most of the reprogramming factors in culture. Their expression is upregulated by hepatocyte growth factor (HGF) and epidermal growth factor (EGF). REST inhibition results in downregulation of reprogramming factor expression, increased apoptosis, decreased proliferation, and cell death. The reprogramming factors are also upregulated after 70% partial hepatectomy in vivo. These findings show that genes inducing iPS phenotype, even though expressed at lower levels than embryonic stem cells, they nonetheless are associated with control of apoptosis and cell proliferation in hepatocytes in culture and may play a role for such processes during liver regeneration. PMID:21739467

  16. Liver regeneration is impaired in macrophage colony stimulating factor deficient mice after partial hepatectomy: the role of M-CSF-induced macrophages.

    PubMed

    Amemiya, Hidetake; Kono, Hiroshi; Fujii, Hideki

    2011-01-01

    Macrophage colony stimulating factor (M-CSF), which induces maturation of macrophages, is notably expressed in the liver. Thus, the specific purpose of this study was to investigate the role of M-CSF in liver regeneration after partial hepatectomy (PH). Osteopetrotic (op/op) mice, genetically lacking functional M-CSF, or their littermate mice underwent 70% PH. Animals were sacrificed at the designated time points after PH, and remnant liver tissues were harvested for further investigations. Proliferation of hepatocytes was evaluated by the expression of BrdU and the liver-body weight ratio. The mRNA expression levels of TNF-α and IL-6 and protein expression levels of phosphorylated (p) STAT3 were measured. The number of Kupffer cells (KCs) was determined by immunohistochemistry. Furthermore, KCs were isolated from op/op mice or littermate mice, and mRNA expression levels of TNF- α and IL-6 were assessed after stimulation with LPS. In littermate mice, steady liver regeneration was observed. The number of KCs reduced markedly by about 60% in the op/op mice compared with littermates as reported previously. Furthermore, these cells were morphologically small and immature. In littermate mice, the peak expression levels of TNF-α and IL-6 in the liver was observed 1h after PH, which was consistent with data in previous reports. In contrast, in op/op mice, the peak expression levels were observed 3 h after PH and were significantly lower compared with littermate mice. As a result, the proliferation of hepatocytes was significantly impaired in op/op mice. The mRNA expression level of IL-6, but not TNF-α,was significantly reduced in isolated KCs from op/op mice compared with the littermates after stimulation with LPS, suggesting that the function of KCs is different between op/op mice and littermate mice. To clarify the role of M-CSF in liver regeneration, op/op mice received intraperitoneally, mouse recombinant M-CSF 2 d before PH, and liver regeneration was also

  17. Expression profiles of the genes associated with metabolism and transport of amino acids and their derivatives in rat liver regeneration.

    PubMed

    Xu, C S; Chang, C F

    2008-01-01

    Amino acids (AA) are components of protein and precursors of many important biological molecules. To address effects of the genes associated with metabolism and transport of AA and their derivatives during rat liver regeneration (LR), we firstly obtained the above genes by collecting databases data and retrieving related thesis, and then analyzed their expression profiles during LR using Rat Genome 230 2.0 array. The LR-associated genes were identified by comparing the gene expression difference between partial hepatectomy (PH) and sham-operation (SO) rat livers. It was approved that 134 genes associated with metabolism of AA and their derivatives and 26 genes involved in transport of them were LR-associated. The initially and totally expressing number of these genes occurring in initial phase of LR (0.5-4 h after PH), G0/G1 (4-6 h after PH), cell proliferation (6-66 h after PH), cell differentiation and structure-function reconstruction of liver tissue (72-168 h after PH) were respectively 76, 17, 79, 5 and 162, 89, 564, 195, illustrating that these LR-associated genes were initially expressed mainly in initial stage, and functioned in different phases. Frequencies of up-regulation and down-regulation of them being separately 564 and 357 demonstrated that genes up-regulated outnumbered those down-regulated. Categorization of their expression patterns into 22 types implied the diversity of cell physiological and biochemical activities. According to expression changes and patterns of the above-mentioned genes in LR, it was presumed that histidine biosynthesis in the metaphase and anaphase, valine metabolism in the anaphase, and metabolism of glutamate, glutamine, asparate, asparagine, methionine, alanine, leucine and aromatic amino acid almost were enhanced in the whole LR; as for amino acid derivatives, transport of neutral amino acids, urea, gamma-aminobutyric acid, betaine and taurine, metabolism of dopamine, heme, S-adenosylmethionine, thyroxine, and

  18. Molecular Survey of Cell Source Usage during Subtotal Hepatectomy-Induced Liver Regeneration in Rats

    PubMed Central

    Elchaninov, Andrey; Fatkhudinov, Timur; Usman, Natalia; Kananykhina, Evgeniya; Arutyunyan, Irina; Makarov, Andrey; Bolshakova, Galina; Goldshtein, Dmitry; Sukhikh, Gennady

    2016-01-01

    Proliferation of hepatocytes is known to be the main process in the hepatectomy-induced liver regrowth; however, in cases of extensive loss it may be insufficient for complete recovery unless supported by some additional sources e.g. mobilization of undifferentiated progenitors. The study was conducted on rat model of 80% subtotal hepatectomy; the objective was to evaluate contributions of hepatocytes and resident progenitor cells to the hepatic tissue recovery via monitoring specific mRNA and/or protein expression levels for a panel of genes implicated in growth, cell differentiation, angiogenesis, and inflammation. Some of the genes showed distinctive temporal expression patterns, which were loosely associated with two waves of hepatocyte proliferation observed at 2 and 7 days after the surgery. Focusing on genes implicated in regulation of the progenitor cell activity, we came across slight increases in expression levels for Sox9 and two genes encoding tumor necrosis factor-like cytokine TWEAK (Tnfsf12) and its receptor Fn14 (Tnfrsf12a). At the same time, no increase in numbers of cytokeratin 19-positive (CK19+) cells was observed in periportal areas, and no CK19+ cells were found in hepatic plates. Since CK19 is thought to be a specific marker of both cholangiocytes and the hepatic progenitor cells, the data indicate a lack of activation of the resident progenitor cells during recovery of hepatic tissue after 80% subtotal hepatectomy. Thus, proliferation of hepatocytes invariably makes the major contribution to the hepatic tissue recovery, although in the cases of subtotal loss this contribution is distinctively modulated. In particular, induction of Sox9 and TWEAK/Fn14 regulatory pathways, conventionally attributed to progenitor cell activation, may incidentally stimulate mitotic activity of hepatocytes. PMID:27631110

  19. Molecular Survey of Cell Source Usage during Subtotal Hepatectomy-Induced Liver Regeneration in Rats.

    PubMed

    Elchaninov, Andrey; Fatkhudinov, Timur; Usman, Natalia; Kananykhina, Evgeniya; Arutyunyan, Irina; Makarov, Andrey; Bolshakova, Galina; Goldshtein, Dmitry; Sukhikh, Gennady

    2016-01-01

    Proliferation of hepatocytes is known to be the main process in the hepatectomy-induced liver regrowth; however, in cases of extensive loss it may be insufficient for complete recovery unless supported by some additional sources e.g. mobilization of undifferentiated progenitors. The study was conducted on rat model of 80% subtotal hepatectomy; the objective was to evaluate contributions of hepatocytes and resident progenitor cells to the hepatic tissue recovery via monitoring specific mRNA and/or protein expression levels for a panel of genes implicated in growth, cell differentiation, angiogenesis, and inflammation. Some of the genes showed distinctive temporal expression patterns, which were loosely associated with two waves of hepatocyte proliferation observed at 2 and 7 days after the surgery. Focusing on genes implicated in regulation of the progenitor cell activity, we came across slight increases in expression levels for Sox9 and two genes encoding tumor necrosis factor-like cytokine TWEAK (Tnfsf12) and its receptor Fn14 (Tnfrsf12a). At the same time, no increase in numbers of cytokeratin 19-positive (CK19+) cells was observed in periportal areas, and no CK19+ cells were found in hepatic plates. Since CK19 is thought to be a specific marker of both cholangiocytes and the hepatic progenitor cells, the data indicate a lack of activation of the resident progenitor cells during recovery of hepatic tissue after 80% subtotal hepatectomy. Thus, proliferation of hepatocytes invariably makes the major contribution to the hepatic tissue recovery, although in the cases of subtotal loss this contribution is distinctively modulated. In particular, induction of Sox9 and TWEAK/Fn14 regulatory pathways, conventionally attributed to progenitor cell activation, may incidentally stimulate mitotic activity of hepatocytes. PMID:27631110

  20. Interactions among LRF-1, JunB, c-Jun, and c-Fos define a regulatory program in the G1 phase of liver regeneration.

    PubMed Central

    Hsu, J C; Bravo, R; Taub, R

    1992-01-01

    In regenerating liver, a physiologically normal model of cell growth, LRF-1, JunB, c-Jun, and c-Fos among Jun/Fos/LRF-1 family members are induced posthepatectomy. In liver cells, high levels of c-Fos/c-Jun, c-Fos/JunB, LRF-1/c-Jun, and LRF-1/JunB complexes are present for several hours after the G0/G1 transition, and the relative level of LRF-1/JunB complexes increases during G1. We provide evidence for dramatic differences in promoter-specific activation by LRF-1- and c-Fos-containing complexes. LRF-1 in combination with either Jun protein strongly activates a cyclic AMP response element-containing promoter which c-Fos/Jun does not activate. LRF-1/c-Jun, c-Fos/c-Jun, and c-Fos/JunB activate specific AP-1 and ATF site-containing promoters, and in contrast, LRF-1/JunB potently represses c-Fos- and c-Jun-mediated activation of these promoters. Repression is dependent on a region in LRF-1 that includes amino acids 40 to 84 (domain R) and the basic/leucine zipper domain. As the relative level of LRF-1/JunB complexes increases posthepatectomy, c-Fos/Jun-mediated ATF and AP-1 site activation is likely to decrease with simultaneous transcriptional activation of the many liver-specific genes whose promoters contain cyclic AMP response element sites. Thus, through complex interactions among LRF-1, JunB, c-Jun, and c-Fos, control of delayed gene expression may be established for extended times during the G1 phase of hepatic growth. Images PMID:1406655

  1. New approaches to increase intestinal length: Methods used for intestinal regeneration and bioengineering

    PubMed Central

    Shirafkan, Ali; Montalbano, Mauro; McGuire, Joshua; Rastellini, Cristiana; Cicalese, Luca

    2016-01-01

    Inadequate absorptive surface area poses a great challenge to the patients suffering a variety of intestinal diseases causing short bowel syndrome. To date, these patients are managed with total parenteral nutrition or intestinal transplantation. However, these carry significant morbidity and mortality. Currently, by emergence of tissue engineering, anticipations to utilize an alternative method to increase the intestinal absorptive surface area are increasing. In this paper, we will review the improvements made over time in attempting elongating the intestine with surgical techniques as well as using intestinal bioengineering. Performing sequential intestinal lengthening was the preliminary method applied in humans. However, these methods did not reach widespread use and has limited outcome. Subsequent experimental methods were developed utilizing scaffolds to regenerate intestinal tissue and organoids unit from the intestinal epithelium. Stem cells also have been studied and applied in all types of tissue engineering. Biomaterials were utilized as a structural support for naive cells to produce bio-engineered tissue that can achieve a near-normal anatomical structure. A promising novel approach is the elongation of the intestine with an acellular biologic scaffold to generate a neo-formed intestinal tissue that showed, for the first time, evidence of absorption in vivo. In the large intestine, studies are more focused on regeneration and engineering of sphincters and will be briefly reviewed. From the review of the existing literature, it can be concluded that significant progress has been achieved in these experimental methods but that these now need to be fully translated into a pre-clinical and clinical experimentation to become a future viable therapeutic option. PMID:27011901

  2. Viral vector-mediated downregulation of RhoA increases survival and axonal regeneration of retinal ganglion cells

    PubMed Central

    Koch, Jan Christoph; Tönges, Lars; Michel, Uwe; Bähr, Mathias; Lingor, Paul

    2014-01-01

    The Rho/ROCK pathway is a promising therapeutic target in neurodegenerative and neurotraumatic diseases. Pharmacological inhibition of various pathway members has been shown to promote neuronal regeneration and survival. However, because pharmacological inhibitors are inherently limited in their specificity, shRNA-mediated approaches can add more information on the function of each single kinase involved. Thus, we generated adeno-associated viral vectors (AAV) to specifically downregulate Ras homologous member A (RhoA) via shRNA. We found that specific knockdown of RhoA promoted neurite outgrowth of retinal ganglion cells (RGC) grown on the inhibitory substrate chondroitin sulfate proteoglycan (CSPG) as well as neurite regeneration of primary midbrain neurons (PMN) after scratch lesion. In the rat optic nerve crush (ONC) model in vivo, downregulation of RhoA significantly enhanced axonal regeneration compared to control. Moreover, survival of RGC transduced with AAV expressing RhoA-shRNA was substantially increased at 2 weeks after optic nerve axotomy. Compared to previous data using pharmacological inhibitors to target RhoA, its upstream regulator Nogo or its main downstream target ROCK, the specific effects of RhoA downregulation shown here were most pronounced in regard to promoting RGC survival but neurite outgrowth and axonal regeneration were also increased significantly. Taken together, we show here that specific knockdown of RhoA substantially increases neuronal survival after optic nerve axotomy and modestly increases neurite outgrowth in vitro and axonal regeneration after optic nerve crush. PMID:25249936

  3. Liver-Specific Expression of Transcriptionally Active SREBP-1c Is Associated with Fatty Liver and Increased Visceral Fat Mass

    PubMed Central

    Knebel, Birgit; Haas, Jutta; Hartwig, Sonja; Jacob, Sylvia; Köllmer, Cornelia; Nitzgen, Ulrike; Muller–Wieland, Dirk; Kotzka, Jorg

    2012-01-01

    The pathogenesis of fatty liver is not understood in detail, but lipid overflow as well as de novo lipogenesis (DNL) seem to be the key points of hepatocyte accumulation of lipids. One key transcription factor in DNL is sterol regulatory element-binding protein (SREBP)-1c. We generated mice with liver-specific over-expression of mature human SREBP-1c under control of the albumin promoter and a liver-specific enhancer (alb-SREBP-1c) to analyze systemic perturbations caused by this distinct alteration. SREBP-1c targets specific genes and causes key enzymes in DNL and lipid metabolism to be up-regulated. The alb-SREBP-1c mice developed hepatic lipid accumulation featuring a fatty liver by the age of 24 weeks under normocaloric nutrition. On a molecular level, clinical parameters and lipid-profiles varied according to the fatty liver phenotype. The desaturation index was increased compared to wild type mice. In liver, fatty acids (FA) were increased by 50% (p<0.01) and lipid composition was shifted to mono unsaturated FA, whereas lipid profile in adipose tissue or serum was not altered. Serum analyses revealed a ∼2-fold (p<0.01) increase in triglycerides and free fatty acids, and a ∼3-fold (p<0.01) increase in insulin levels, indicating insulin resistance; however, no significant cytokine profile alterations have been determined. Interestingly and unexpectedly, mice also developed adipositas with considerably increased visceral adipose tissue, although calorie intake was not different compared to control mice. In conclusion, the alb-SREBP-1c mouse model allowed the elucidation of the systemic impact of SREBP-1c as a central regulator of lipid metabolism in vivo and also demonstrated that the liver is a more active player in metabolic diseases such as visceral obesity and insulin resistance. PMID:22363740

  4. Calpain 2-mediated autophagy defect increases susceptibility of fatty livers to ischemia–reperfusion injury

    PubMed Central

    Zhao, Q; Guo, Z; Deng, W; Fu, S; Zhang, C; Chen, M; Ju, W; Wang, D; He, X

    2016-01-01

    Hepatic steatosis is associated with significant morbidity and mortality after liver resection and transplantation. This study focuses on the role of autophagy in regulating sensitivity of fatty livers to ischemia and reperfusion (I/R) injury. Quantitative immunohistochemistry conducted on human liver allograft biopsies showed that, the reduction of autophagy markers LC3 and Beclin-1 at 1 h after reperfusion, was correlated with hepatic steatosis and poor survival of liver transplant recipients. In animal studies, western blotting and confocal imaging analysis associated the increase in sensitivity to I/R injury with low autophagy activity in fatty livers. Screening of autophagy-related proteins showed that Atg3 and Atg7 expression levels were marked decreased, whereas calpain 2 expression was upregulated during I/R in fatty livers. Calpain 2 inhibition or knockdown enhanced autophagy and suppressed cell death. Further point mutation experiments revealed that calpain 2 cleaved Atg3 and Atg7 at Atg3Δ92–97 and Atg7Δ344–349, respectively. In vivo and in vitro overexpression of Atg3 or Atg7 enhanced autophagy and suppressed cell death after I/R in fatty livers. Collectively, calpain 2-mediated degradation of Atg3 and Atg7 in fatty livers increases their sensitivity to I/R injury. Increasing autophagy may ameliorate fatty liver damage and represent a valuable method to expand the liver donor pool. PMID:27077802

  5. Defective Initiation of Liver Regeneration in Osteopontin-Deficient Mice after Partial Hepatectomy due to Insufficient Activation of IL-6/Stat3 Pathway.

    PubMed

    Wen, Yankai; Feng, Dechun; Wu, Hailong; Liu, Wenjun; Li, Hongjie; Wang, Fang; Xia, Qiang; Gao, Wei-Qiang; Kong, Xiaoni

    2015-01-01

    The initial process in liver regeneration after partial hepatectomy involves the recruitment of immune cells and the release of cytokines. Osteopontin (OPN), a pro-inflammatory protein, plays critical roles in immune cell activation and migration. Although OPN has been implicated in the pathogenesis of many liver diseases, the role of OPN in liver regeneration remains obscure. In the present study, we found that serum and hepatic OPN protein levels were significantly elevated in wild-type (WT) mice after partial hepatectomy (PHx) and that bile ductal epithelia were the major cell source of hepatic OPN. Compared to WT mice, OPN knockout (KO) mice exhibited delayed liver regeneration after PHx. This delay in OPN(-/-) mice was attributed to impaired hepatic infiltration of macrophages and neutrophils, decreased serum and hepatic IL-6 levels, and blunted activation of macrophages after PHx. Furthermore, we demonstrate that the attenuated activation of macrophages is at least partially due to decreased hepatic and portal vein LPS levels in OPN(-/-) mice. In response to decreased IL-6 levels, the activation of signal transducer and transcription (Stat) 3 was reduced in hepatocytes of OPN(-/-) mice compared to WT mice after PHx. Consequently, hepatic activation of the downstream direct targets of IL6/Stat3, such as c-fos, c-jun, and c-myc, was also suppressed post-PHx in OPN(-/-) mice compared to WT mice. Collectively, these results support a unique role for OPN during the priming phase of liver regeneration, in which OPN enhances the recruitment of macrophages and neutrophils, and triggers hepatocyte proliferation through Kupffer cell-derived IL-6 release and the downstream activation of Stat3.

  6. Increased Gal-9 and Tim-3 expressions during liver damage in a murine malarial model.

    PubMed

    Xiao, Siyu; Liu, Jinfeng; Huang, Shiguang; Lu, Fangli

    2016-02-01

    Malaria has been one of the most devastating tropical parasite infectious diseases popular around the world. Severe malaria is characterized by multiple organ dysfunctions, especially liver damage. However, the mechanisms of malarial liver injury remain to be better clarified. In this study, Kunming mice inoculated intraperitoneally (i.p.) with 10(6) Plasmodium berghei ANKA (PbANKA)-infected red blood cells (iRBCs) were investigated at days 5, 10, 15, and 20 post-infection (p.i.) to elucidate the profiles of T-cell immunoglobulin and mucin domain-3 (Tim-3) and its ligand galecin-9 (Gal-9) in the development of liver injury. The histopathology of livers and spleens from PbANKA-infected mice were observed, the parasite burdens of the livers and spleens using quantitative real-time PCR (qRT-PCR), Tim-3- and Gal-9-positive cells in the livers and spleens using immunohistochemical staining, and the mRNA levels of Tim-3, Gal-9, and cytokines in both the livers and spleens using qRT-PCR were examined. Our results showed that parasite burdens in the livers and spleens were significantly increased with time after PbANKA infection. Histological scores of both the liver and spleen tissues were significantly increased with time; the numbers of Tim-3- and Gal-9-positive cells were significantly increased in both the livers and spleens using immunohistochemical staining, and the mRNA levels of Tim-3 and Gal-9 in the livers and spleens were also significantly increased after infection. Our data suggests that the increase of Tim-3/Gal-9 expressions may play an important role in the liver damage during P. berghei infection.

  7. High level increase in liver enzymes and severe thrombocytopenia in a male case of anorexia nervosa*

    PubMed Central

    Karahmadi, Mojgan; Layegh, Elmira; Layegh, Samira; Keypour, Maryam

    2011-01-01

    BACKGROUND: Anorexia nervosa (AN) is a difficult-to-treat psychosomatic disease. Very few cases of acute liver failure associated with AN have been described. We describe one patient who was affected by AN and presented high level increase of serum liver enzymes, along with sever thrombocytopenia. Then, we discuss the possible etiopathogenic factors. METHODS: A 14-year-old boy with AN was admitted in the pediatric psychiatric emergency department of Alzahra Hospital with impaired electrolyte levels, bradycardia, hypotension, liver dysfunction, and thrombocytopenia. RESULTS: A ten-time increase in liver enzymes and thrombocytopenia were observed on admission. After two months of treatment, the levels were within the normal range. CONCLUSIONS: Improvement of initial clinical symptoms and recovery of liver enzymes and thrombocytopenia after the treatment suggested that liver dysfunction and thrombocytopenia may be observed in AN patients and should be taken care of by physicians. PMID:22973335

  8. Increased liver carcinogenesis and enrichment of stem cell properties in livers of Dickkopf 2 (Dkk2) deleted mice.

    PubMed

    Maass, Thorsten; Marquardt, Jens; Lee, Ju-Seog; Krupp, Markus; Scholz-Kreisel, Peter; Mogler, Carolin; Schirmacher, Peter; Müller, Martina; Westphal, Heiner; Galle, Peter R; Teufel, Andreas

    2016-05-17

    Dkk2 a antagonist of the Wnt/β-catenin-signaling pathway was shown to be silenced in diverse cancers. More recent data indicate that Dkk family members may also possess functions independent of Wnt-signaling during carcinogenesis. The detailed biological function of Dkks and its relevance for liver cancer is unknown. We analyzed the effects of a genetic deletion of Dkk2 (Dkk2-/-) in a hepatocarcinogenesis model using DEN/Phenobarbital. Untreated Dkk2-/- animals, showed considerable atypia with variation of hepatocyte size and chromatin density. In livers of Dkk2-/- mice nodule formation was seen at 9 months of age with focal loss of trabecular architecture and atypical hepatocytes and after DEN induction Dkk2-/- mice developed significantly more liver tumors compared to controls. Whole transcriptome analysis of untreated Dkk2-/- liver tissue revealed a Dkk2-dependent genetic network involving Wnt/β-Catenin but also multiple additional oncogenic factors, such as e.g. Pdgf-b, Gdf-15 and Hnf4a. Dkk2-/- tumor cells showed a significant deregulation of stemness genes associated with enhanced colony forming properties. Integration of the Dkk2-/- signature into human data was strongly associated with patients survival. Dkk2 deletion results in alterations of liver morphology leading to an increased frequency of liver cancer. The associated genetic changes included factors not primarily related to Wnt/β-Catenin-signaling and correlated with the clinical outcome of HCC-patients.

  9. In vitro expansion of single Lgr5+ liver stem cells induced by Wnt-driven regeneration

    PubMed Central

    Huch, Meritxell; Dorrell, Craig; Boj, Sylvia F.; van Es, Johan H.; van de Wetering, Marc; Li, Vivian S.W.; Hamer, Karien; Sasaki, Nobuo; Finegold, Milton J.; Haft, Annelise; Grompe, Markus; Clevers, Hans

    2013-01-01

    The Wnt target gene Lgr5 marks actively dividing stem cells in Wnt-driven, self-renewing tissues such as small intestine and colon1, stomach2 and hair follicles3. A 3D culture system allows long-term clonal expansion of single Lgr5+ stem cells into transplantable organoids that retain many characteristics of the original epithelial architecture2, 4, 5. A crucial component of the culture medium is the Wnt agonist Rspo16, the recently discovered ligand of Lgr57, 8. Here we show that Lgr5-LacZ is not expressed in healthy adult liver, yet that small Lgr5-LacZ+ cells appear near bile ducts upon damage, coinciding with robust activation of Wnt signaling. As shown by lineage tracing using a novel Lgr5-ires-CreERT2 knock-in allele, damage-induced Lgr5+ cells generate hepatocytes and bile ducts in vivo. Single Lgr5+ cells from damaged liver can be clonally expanded as organoids in Rspo1-based culture medium over multiple months. Such clonal organoids can be induced to differentiate in vitro and to generate functional hepatocytes upon transplantation into FAH−/− mice. These findings imply that previous observations on Lgr5+ stem cells in actively self-renewing tissues extend to damage-induced stem cells in a tissue with a low rate of spontaneous proliferation. PMID:23354049

  10. Hepatoprotective Effects of Schisandra sphenanthera Extract against Lithocholic Acid-Induced Cholestasis in Male Mice Are Associated with Activation of the Pregnane X Receptor Pathway and Promotion of Liver Regeneration.

    PubMed

    Zeng, Hang; Li, Dongshun; Qin, Xiaoling; Chen, Pan; Tan, Huasen; Zeng, Xuezhen; Li, Xi; Fan, Xiaomei; Jiang, Yiming; Zhou, Yawen; Chen, Yixin; Wang, Ying; Huang, Min; Bi, Huichang

    2016-03-01

    We previously reported that the ethanol extract of Schisandra sphenanthera [Wuzhi (WZ) tablet] significantly protects against acetaminophen-induced hepatoxicity. However, whether WZ exerts a protective effect against cholestasis remains unclear. In this study, the protective effect of WZ on lithocholic acid (LCA)-induced intrahepatic cholestasis in mice was characterized and the involved mechanisms were investigated. WZ pretreatment (350 mg/kg) with LCA significantly reversed liver necrosis and decreased serum alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase activity. More importantly, serum total bile acids and total bilirubin were also remarkably reduced. Quantitative reverse-transcription polymerase chain reaction and Western blot analysis showed that hepatic expression of pregnane X receptor (PXR) target genes such as CYP3A11 and UDP-glucuronosyltransferase (UGT) 1A1 were significantly increased by WZ treatment. Luciferase assays performed in LS174T cells illustrated that WZ extract and its six bioactive lignans could all activate human PXR. In addition, WZ treatment significantly promoted liver regeneration via inhibition of p53/p21 to induce cell proliferation-associated proteins such as cyclin D1 and proliferating cell nuclear antigen. In conclusion, WZ has a protective effect against LCA-induced intrahepatic cholestasis, partially owing to activation of the PXR pathway and promotion of liver regeneration.

  11. Epoprostenol (prostacyclin,PGI2) increases apparent liver blood flow in man.

    PubMed

    Hassan, S; Pickles, H

    1983-04-01

    When epoprostenol (prostacyclin, PGI2) is given by infusion to man, cardiac output is increased, and it appears that the gastrointestinal tract may receive a disproportionate share of this. We have used the clearance of indocyanine green dye to estimate liver blood flow in 8 healthy subjects. During an infusion of PGI2 at a dose of 5 ng/kg/min, apparent liver blood flow increased from 925 +/- 220 ml/min (Mean +/- s.d) to 1320 +/- 453 ml/min, an average increase of 41.1%. Significant changes in heart rate, headache, facial flushing, systolic blood pressure, and pulse pressure were noticed. We suggest that endogenous epoprostenol (PGI2) may be of importance in the physiological regulation of liver blood flow in man. As this dose of epoprostenol could be tolerated readily, epoprostenol therapy could prove a therapeutic advance in some liver disorders, particularly liver transplantation, and possibly in the therapy of certain drug overdoses. PMID:6344102

  12. Modulation of ornithine decarboxylase activity in the normal and regenerating rat liver by various doses of the peptide morphogen of Hydra

    SciTech Connect

    Yarygin, K.N.; Kazimirskii, A.N.; Kositskii, G.I.; Rubina, A.Yu.; Vinogradov, V.A.; Pylaev, A.S.

    1986-11-01

    In this investigation, changes in ornithine decarboxylase (ODC) activity were studied in the normal and regenerating liver of rats receiving injections of various doses of Hydra peptide morphogen (HPM). Activity of ODC was determined by a radioisotope method based on liberation of /sup 14/CO/sub 2/ from L-(1-/sup 14/C)-ornithine. The results indicate in the author's opinion that HPM may have a role in the regulation of anabolic processes and, in particular, of regenerative processes in mammals.

  13. [Modification of recombinant human augmenter of liver regeneration with urea studied by maldi-tof mass spectrometry].

    PubMed

    Pan, Yun; He, Guo-Qing; Li, Ru-Bing; Yi, Xue-Rui; Kong, Xiang-Ping

    2003-04-01

    To investigate the modification of recombinant human augmenter of liver regeneration (rhALR) by the urea in purification processes and the biological activity of rhALR and modified rhALR, the molecular weight of proteins and tryptic peptides were determined by matrix-assisted laser desorption time of flight mass spectrometry (MALDI-TOF-MS), and the biological activity of rhALR and modified rhALR was also observed by in vivo experiments. A 30 kD homodimer of rhALR was purified under denaturing conditions. The molecular weight of rhALR is 30 780 if urea was used to denature the inclusion bodies; when the denaturant was guanidine hydrochloride, the molecular weight of rhALR was 30 087. The results of MALDI-TOF-MS of digested rhALR that have been modified by urea showed that peptides that contained lysyl were 43 larger than the theoretical value. Proteins purified by different processes were all able to promote the survival rate of CCl(4)-intoxicated mice. It could be concluded that cyanate, the cleavage product of urea, could react with the epsilon-amino group of lysyl in rhALR, and the modified rhALR had the same biological activity as natural rhALR.

  14. Stimulating Myocardial Regeneration with Periostin Peptide in Large Mammals Improves Function Post-Myocardial Infarction but Increases Myocardial Fibrosis

    PubMed Central

    Ladage, Dennis; Yaniz-Galende, Elisa; Rapti, Kleopatra; Ishikawa, Kiyotake; Tilemann, Lisa; Shapiro, Scott; Takewa, Yoshiaki; Muller-Ehmsen, Jochen; Schwarz, Martin; Garcia, Mario J.; Sanz, Javier; Hajjar, Roger J.; Kawase, Yoshiaki

    2013-01-01

    Aims Mammalian myocardium has a finite but limited capacity to regenerate. Experimentally stimulating proliferation of cardiomyocytes with extracellular regeneration factors like periostin enhances cardiac repair in rodents. The aim of this study was to develop a safe method for delivering regeneration factors to the heart and to test the functional and structural effects of periostin peptide treatment in a large animal model of myocardial infarction (MI). Methods and Results We developed a controlled release system to deliver recombinant periostin peptide into the pericardial space. A single application of this method was performed two days after experimental MI in swine. Animals were randomly assigned to receive either saline or periostin peptide. Experimental groups were compared at baseline, day 2, 1 month and 3 months. Treatment with periostin peptide increased the EF from 31% to 41% and decreased by 22% the infarct size within 12 weeks. Periostin peptide-treated animals had newly formed myocardium strips within the infarct scar, leading to locally improved myocardial function. In addition the capillary density was increased in animals receiving periostin. However, periostin peptide treatment increased myocardial fibrosis in the remote region at one week and 12 weeks post-treatment. Conclusion Our study shows that myocardial regeneration through targeted peptides is possible. However, in the case of periostin the effects on cardiac fibrosis may limit its clinical application as a viable therapeutic strategy. PMID:23700403

  15. Factors promoting increased rate of tissue regeneration: the zebrafish fin as a tool for examining tissue engineering design concepts.

    PubMed

    Boominathan, Vijay P; Ferreira, Tracie L

    2012-12-01

    Student interest in topics of tissue engineering is increasing exponentially as the number of universities offering programs in bioengineering are on the rise. Bioengineering encompasses all of the STEM categories: Science, Technology, Engineering, and Math. Inquiry-based learning is one of the most effective techniques for promoting student learning and has been demonstrated to have a high impact on learning outcomes. We have designed program outcomes for our bioengineering program that require tiered activities to develop problem solving skills, peer evaluation techniques, and promote team work. While it is ideal to allow students to ask unique questions and design their own experiments, this can be difficult for instructors to have reagents and supplies available for a variety of activities. Zebrafish can be easily housed, and multiple variables can be tested on a large enough group to provide statistical value, lending them well to inquiry-based learning modules. We have designed a laboratory activity that takes observation of fin regeneration to the next level: analyzing conditions that may impact regeneration. Tissue engineers seek to define the optimum conditions to grow tissue for replacement parts. The field of tissue engineering is likely to benefit from understanding natural mechanisms of regeneration and the factors that influence the rate of regeneration. We have outlined the results of varying temperature on fin regeneration and propose other inquiry modules such as the role of pH in fin regeneration. Furthermore, we have provided useful tools for developing critical thinking and peer review of research ideas, assessment guidelines, and grading rubrics for the activities associated with this exercise. PMID:23244692

  16. Factors promoting increased rate of tissue regeneration: the zebrafish fin as a tool for examining tissue engineering design concepts.

    PubMed

    Boominathan, Vijay P; Ferreira, Tracie L

    2012-12-01

    Student interest in topics of tissue engineering is increasing exponentially as the number of universities offering programs in bioengineering are on the rise. Bioengineering encompasses all of the STEM categories: Science, Technology, Engineering, and Math. Inquiry-based learning is one of the most effective techniques for promoting student learning and has been demonstrated to have a high impact on learning outcomes. We have designed program outcomes for our bioengineering program that require tiered activities to develop problem solving skills, peer evaluation techniques, and promote team work. While it is ideal to allow students to ask unique questions and design their own experiments, this can be difficult for instructors to have reagents and supplies available for a variety of activities. Zebrafish can be easily housed, and multiple variables can be tested on a large enough group to provide statistical value, lending them well to inquiry-based learning modules. We have designed a laboratory activity that takes observation of fin regeneration to the next level: analyzing conditions that may impact regeneration. Tissue engineers seek to define the optimum conditions to grow tissue for replacement parts. The field of tissue engineering is likely to benefit from understanding natural mechanisms of regeneration and the factors that influence the rate of regeneration. We have outlined the results of varying temperature on fin regeneration and propose other inquiry modules such as the role of pH in fin regeneration. Furthermore, we have provided useful tools for developing critical thinking and peer review of research ideas, assessment guidelines, and grading rubrics for the activities associated with this exercise.

  17. Exercise dependent increase in axon regeneration into peripheral nerve grafts by propriospinal but not sensory neurons after spinal cord injury is associated with modulation of regeneration-associated genes.

    PubMed

    Sachdeva, Rahul; Theisen, Catherine C; Ninan, Vinu; Twiss, Jeffery L; Houlé, John D

    2016-02-01

    Insufficient regeneration of central nervous system (CNS) axons contributes to persisting neurological dysfunction after spinal cord injury (SCI). Peripheral nerve grafts (PNGs) support regeneration by thousands of injured intraspinal axons and help them bypass some of the extracellular barriers that form after SCI. However this number represents but a small portion of the total number of axons that are injured. Here we tested if rhythmic sensory stimulation during cycling exercise would boost the intrinsic regenerative state of neurons to enhance axon regeneration into PNGs after a lower thoracic (T12) spinal transection of adult rats. Using True Blue retrograde tracing, we show that 4 weeks of cycling improves regeneration into a PNG from lumbar interneurons but not by primary sensory neurons. The majority of neurons that regenerate their axon are within 5 mm of the lesion and their number increased 70% with exercise. Importantly propriospinal neurons in more distant regions (5-20 mm from the lesion) that routinely exhibit very limited regeneration responded to exercise by increasing the number of regenerating neurons by 900%. There was no exercise-associated increase in regeneration from sensory neurons. Analyses using fluorescent in situ hybridization showed that this increase in regenerative response is associated with changes in levels of mRNAs encoding the regeneration associated genes (RAGs) GAP43, β-actin and Neuritin. While propriospinal neurons showed increased mRNA levels in response to SCI alone and then to grafting and exercise, sensory neurons did not respond to SCI, but there was a response to the presence of a PNG. Thus, exercise is a non-invasive approach to modulate gene expression in injured neurons leading to an increase in regeneration. This sets the stage for future studies to test whether exercise will promote axon outgrowth beyond the PNG and reconnection with spinal cord neurons, thereby demonstrating a potential clinical application of

  18. Exercise dependent increase in axon regeneration into peripheral nerve grafts by propriospinal but not sensory neurons after spinal cord injury is associated with modulation of regeneration-associated genes.

    PubMed

    Sachdeva, Rahul; Theisen, Catherine C; Ninan, Vinu; Twiss, Jeffery L; Houlé, John D

    2016-02-01

    Insufficient regeneration of central nervous system (CNS) axons contributes to persisting neurological dysfunction after spinal cord injury (SCI). Peripheral nerve grafts (PNGs) support regeneration by thousands of injured intraspinal axons and help them bypass some of the extracellular barriers that form after SCI. However this number represents but a small portion of the total number of axons that are injured. Here we tested if rhythmic sensory stimulation during cycling exercise would boost the intrinsic regenerative state of neurons to enhance axon regeneration into PNGs after a lower thoracic (T12) spinal transection of adult rats. Using True Blue retrograde tracing, we show that 4 weeks of cycling improves regeneration into a PNG from lumbar interneurons but not by primary sensory neurons. The majority of neurons that regenerate their axon are within 5 mm of the lesion and their number increased 70% with exercise. Importantly propriospinal neurons in more distant regions (5-20 mm from the lesion) that routinely exhibit very limited regeneration responded to exercise by increasing the number of regenerating neurons by 900%. There was no exercise-associated increase in regeneration from sensory neurons. Analyses using fluorescent in situ hybridization showed that this increase in regenerative response is associated with changes in levels of mRNAs encoding the regeneration associated genes (RAGs) GAP43, β-actin and Neuritin. While propriospinal neurons showed increased mRNA levels in response to SCI alone and then to grafting and exercise, sensory neurons did not respond to SCI, but there was a response to the presence of a PNG. Thus, exercise is a non-invasive approach to modulate gene expression in injured neurons leading to an increase in regeneration. This sets the stage for future studies to test whether exercise will promote axon outgrowth beyond the PNG and reconnection with spinal cord neurons, thereby demonstrating a potential clinical application of

  19. Increased liver carcinogenesis and enrichment of stem cell properties in livers of Dickkopf 2 (Dkk2) deleted mice

    PubMed Central

    Maass, Thorsten; Marquardt, Jens; Lee, Ju-Seog; Krupp, Markus; Scholz-Kreisel, Peter; Mogler, Carolin; Schirmacher, Peter; Müller, Martina; Westphal, Heiner; Galle, Peter R.; Teufel, Andreas

    2016-01-01

    Dkk2 a antagonist of the Wnt/β-catenin-signaling pathway was shown to be silenced in diverse cancers. More recent data indicate that Dkk family members may also possess functions independent of Wnt-signaling during carcinogenesis. The detailed biological function of Dkks and its relevance for liver cancer is unknown. We analyzed the effects of a genetic deletion of Dkk2 (Dkk2−/−) in a hepatocarcinogenesis model using DEN/Phenobarbital. Untreated Dkk2−/− animals, showed considerable atypia with variation of hepatocyte size and chromatin density. In livers of Dkk2−/− mice nodule formation was seen at 9 months of age with focal loss of trabecular architecture and atypical hepatocytes and after DEN induction Dkk2−/− mice developed significantly more liver tumors compared to controls. Whole transcriptome analysis of untreated Dkk2−/− liver tissue revealed a Dkk2-dependent genetic network involving Wnt/β-Catenin but also multiple additional oncogenic factors, such as e.g. Pdgf-b, Gdf-15 and Hnf4a. Dkk2−/− tumor cells showed a significant deregulation of stemness genes associated with enhanced colony forming properties. Integration of the Dkk2−/− signature into human data was strongly associated with patients survival. Dkk2 deletion results in alterations of liver morphology leading to an increased frequency of liver cancer. The associated genetic changes included factors not primarily related to Wnt/β-Catenin-signaling and correlated with the clinical outcome of HCC-patients. PMID:25826080

  20. Phosphatase of regenerating liver-3 inhibits invasiveness and proliferation in non-small cell lung cancer by regulating the epithelial-mesenchymal transition

    PubMed Central

    Lin, Sheng-Yi; Lee, Yue-Xun; Yu, Sung-Liang

    2016-01-01

    Phosphatase of regenerating liver-3 (PRL-3) has been reported to be associated with colon and gastric cancer metastasis. However, the role and function of PRL-3 in human non-small cell lung cancer cells is unknown. Our studies showed that the expression of PRL-3mRNA and protein are higher in less invasive human lung adenocarcinoma cells than in highly invasive cell lines. Ectopic expression of PRL-3 reduced cell capacity for anchorage-dependent growth, anchorage-independent growth, migration, and invasion in vitro, as well as tumorigenesis in vivo. Conversely, catalytic (C104S) and prenylation-site (C170S) mutants enhanced cell invasion. Microarray profiling of PRL-3 transfectants revealed the pathways potentially involving PRL-3, including the epithelial-mesenchymal transition (EMT), extracellular matrix remodeling, and the WNT signaling pathway. Furthermore, we demonstrated that increased PRL-3 reduced Slug and enhanced E-cadherin gene expression through the AKT/GSK3β/β-catenin pathway. In conclusion, our data suggest that PRL-3 might play a tumor suppressor role in lung cancer, distinct from other cancers, by inhibiting EMT-related pathways. PMID:26967563

  1. Obesity Increases Sensitivity to Endotoxin Liver Injury: Implications for the Pathogenesis of Steatohepatitis

    NASA Astrophysics Data System (ADS)

    Yang, Shi Qi; Zhi Lin, Hui; Lane, M. Daniel; Clemens, Mark; Diehl, Anna Mae

    1997-03-01

    Genetically obese fatty/fatty rats and obese/obese mice exhibit increased sensitivity to endotoxin hepatotoxicity, quickly developing steatohepatitis after exposure to low doses of lipopolysaccharide (LPS). Among obese animals, females are more sensitive to endotoxin liver injury than males. LPS induction of tumor necrosis factor α (TNFα ), the proven affecter of endotoxin liver injury, is no greater in the livers, white adipose tissues, or sera of obese animals than in those of lean controls. Indeed, the lowest serum concentrations of TNF occur in female obese rodents, which exhibit the most endotoxin-induced liver injury. Several cytokines that modulate the biological activity of TNF are regulated abnormally in the livers of obese animals. After exposure to LPS, mRNA of interferon γ , which sensitizes hepatocytes to TNF toxicity, is overexpressed, and mRNA levels of interleukin 10, a TNF inhibitor, are decreased. The phagocytic activity of liver macrophages and the hepatic expression of a gene encoding a macrophage-specific receptor are also decreased in obesity. This new animal model of obesity-associated liver disease demonstrates that hepatic macrophage dysfunction occurs in obesity and suggests that this might promote steatohepatitis by sensitizing hepatocytes to endotoxin.

  2. FXR and liver carcinogenesis

    PubMed Central

    Huang, Xiong-fei; Zhao, Wei-yu; Huang, Wen-dong

    2015-01-01

    Farnesoid X receptor (FXR) is a member of the nuclear receptor family and a ligand-modulated transcription factor. In the liver, FXR has been considered a multi-functional cell protector and a tumor suppressor. FXR can suppress liver carcinogenesis via different mechanisms: 1) FXR maintains the normal liver metabolism of bile acids, glucose and lipids; 2) FXR promotes liver regeneration and repair after injury; 3) FXR protects liver cells from death and enhances cell survival; 4) FXR suppresses hepatic inflammation, thereby preventing inflammatory damage; and 5) FXR can directly increase the expression of some tumor-suppressor genes and repress the transcription of several oncogenes. However, inflammation and epigenetic silencing are known to decrease FXR expression during tumorigenesis. The reactivation of FXR function in the liver may be a potential therapeutic approach for patients with liver cancer. PMID:25500874

  3. Noninvasive 3-dimensional imaging of liver regeneration in a mouse model of hereditary tyrosinemia type 1 using the sodium iodide symporter gene.

    PubMed

    Hickey, Raymond D; Mao, Shennen A; Amiot, Bruce; Suksanpaisan, Lukkana; Miller, Amber; Nace, Rebecca; Glorioso, Jaime; O'Connor, Michael K; Peng, Kah Whye; Ikeda, Yasuhiro; Russell, Stephen J; Nyberg, Scott L

    2015-04-01

    Cell transplantation is a potential treatment for the many liver disorders that are currently only curable by organ transplantation. However, one of the major limitations of hepatocyte (HC) transplantation is an inability to monitor cells longitudinally after injection. We hypothesized that the thyroidal sodium iodide symporter (NIS) gene could be used to visualize transplanted HCs in a rodent model of inherited liver disease: hereditary tyrosinemia type 1. Wild-type C57Bl/6J mouse HCs were transduced ex vivo with a lentiviral vector containing the mouse Slc5a5 (NIS) gene controlled by the thyroxine-binding globulin promoter. NIS-transduced cells could robustly concentrate radiolabeled iodine in vitro, with lentiviral transduction efficiencies greater than 80% achieved in the presence of dexamethasone. Next, NIS-transduced HCs were transplanted into congenic fumarylacetoacetate hydrolase knockout mice, and this resulted in the prevention of liver failure. NIS-transduced HCs were readily imaged in vivo by single-photon emission computed tomography, and this demonstrated for the first time noninvasive 3-dimensional imaging of regenerating tissue in individual animals over time. We also tested the efficacy of primary HC spheroids engrafted in the liver. With the NIS reporter, robust spheroid engraftment and survival could be detected longitudinally after direct parenchymal injection, and this thereby demonstrated a novel strategy for HC transplantation. This work is the first to demonstrate the efficacy of NIS imaging in the field of HC transplantation. We anticipate that NIS labeling will allow noninvasive and longitudinal identification of HCs and stem cells in future studies related to liver regeneration in small and large preclinical animal models.

  4. Role of phosphatase of regenerating liver 1 (PRL1) in spermatogenesis

    PubMed Central

    Bai, Yunpeng; Zhou, Hong-Ming; Zhang, Lujuan; Dong, Yuanshu; Zeng, Qi; Shou, Weinian; Zhang, Zhong-Yin

    2016-01-01

    The PRL phosphatases are oncogenic when overexpressed but their in vivo biological function is less well understood. Previous gene deletion study revealed a role for PRL2 in spermatogenesis. We report here the first knockout mice lacking PRL1, the most related homolog of PRL2. We found that loss of PRL1 does not affect spermatogenesis and reproductive ability of male mice, likely due to functional compensation by the relatively higher expression of PRL2 in the testes. However, PRL1−/−/PRL2+/− male mice show testicular atrophy phenotype similar to PRL2−/− mice. More strikingly, deletion of one PRL1 allele in PRL2−/− male mice causes complete infertility. Mechanistically, the total level of PRL1 and PRL2 is negatively correlated with the PTEN protein level in the testis and PRL1+/−/PRL2−/− mice have the highest level of PTEN, leading to attenuated Akt activation and increased germ cell apoptosis, effectively halting spermatozoa production. These results provide the first evidence that in addition to PRL2, PRL1 is also required for spermatogenesis by downregulating PTEN and promoting Akt signaling. The ability of the PRLs to suppress PTEN expression underscores the biochemical basis for their oncogenic potential. PMID:27666520

  5. Increased slow transport in axons of regenerating newt limbs after a nerve conditioning lesion made prior to amputation

    SciTech Connect

    Maier, C.E.

    1989-01-01

    The first part of this study shows that axonal density is constant in the limb stump of the next proximal to the area of traumatic nerve degeneration caused by limb amputation. The results of the second part of this work reveal that a nerve conditioning lesion made two weeks prior to amputation is associated with accelerated limb regeneration and that this accelerated limb regeneration is accompanied by an earlier arrival of axons. This is the first demonstration of naturally occurring limb regeneration being enhanced. In this study SCb cytoskeletal proteins were identified and measured using SDS-PAGE and liquid scintillation counting. Proteins were measured at 7, 14, 21, and 28 days after {sup 35}S-methionine injection and the normal rate of SCb transport determined to be 0.19 mm/day. A single axotomy does not enhance the rate of SCb transport but does increase the amount of labeled SCb proteins that are transported. When a conditioning lesion is employed prior to limb amputation and SCb proteins are measured at 7, 14, and 21 days after injection, there is a twofold acceleration in the rate of SCb transport and an increase in the amount of SCb proteins transported in conditioned axons.

  6. Regenerating livers of old rats contain high levels of C/EBPalpha that correlate with altered expression of cell cycle associated proteins.

    PubMed Central

    Timchenko, N A; Wilde, M; Kosai, K I; Heydari, A; Bilyeu, T A; Finegold, M J; Mohamedali, K; Richardson, A; Darlington, G J

    1998-01-01

    The nuclear transcription factor, CCAAT/enhancer binding protein alpha (C/EBPalpha) is expressed at high levels in the liver and inhibits growth in cultured cells. We have tested the correlation between C/EBPalpha levels, cell cycle proteins and hepatocyte proliferation in old and young animals as an in vivo model system in which the proliferative response to partial hepatectomy (PH) has been shown to be reduced and delayed in old animals. Here we present evidence that the expression of C/EBPalpha in old rats (24 months) differs from its expression in young animals (6-10 months) during liver regeneration. Induction of proliferating cell nuclear antigen (PCNA), a marker of DNA synthesis, occurs at 24 h after PH in young rats but is delayed and reduced in old animals. Induction of the mitotic-specific protein, cdc2 p34, is 3-4-fold less in regenerating liver of old rats than in the liver of young animals, confirming the reduced proliferative response in old animals. In young rats, the normal regenerative response involves a reduction of 3-4-fold in the levels of C/EBPalpha protein at 3-24 h. In old animals, C/EBPalpha is not reduced within 24 h after PH, but a decrease of C/EBPalpha protein levels can be detected at 72 h after PH. Induction of C/EBPbeta, another member of the C/EBP family, is delayed in old animals. Changes in the expression of C/EBP proteins are accompanied by alteration of the CDK inhibitor, p21, which is also decreased in young rats after PH, but in old animals remains unchanged. High levels of p21 protein in older animals correlate with the lack of cdk2 activation. We suggest that the failure to reduce the amount of C/EBPalpha and p21 is a critical event in the dysregulation of hepatocyte proliferation in old animals following PH. PMID:9628932

  7. TISSUE REGENERATION. Inhibition of the prostaglandin-degrading enzyme 15-PGDH potentiates tissue regeneration.

    PubMed

    Zhang, Yongyou; Desai, Amar; Yang, Sung Yeun; Bae, Ki Beom; Antczak, Monika I; Fink, Stephen P; Tiwari, Shruti; Willis, Joseph E; Williams, Noelle S; Dawson, Dawn M; Wald, David; Chen, Wei-Dong; Wang, Zhenghe; Kasturi, Lakshmi; Larusch, Gretchen A; He, Lucy; Cominelli, Fabio; Di Martino, Luca; Djuric, Zora; Milne, Ginger L; Chance, Mark; Sanabria, Juan; Dealwis, Chris; Mikkola, Debra; Naidoo, Jacinth; Wei, Shuguang; Tai, Hsin-Hsiung; Gerson, Stanton L; Ready, Joseph M; Posner, Bruce; Willson, James K V; Markowitz, Sanford D

    2015-06-12

    Agents that promote tissue regeneration could be beneficial in a variety of clinical settings, such as stimulating recovery of the hematopoietic system after bone marrow transplantation. Prostaglandin PGE2, a lipid signaling molecule that supports expansion of several types of tissue stem cells, is a candidate therapeutic target for promoting tissue regeneration in vivo. Here, we show that inhibition of 15-hydroxyprostaglandin dehydrogenase (15-PGDH), a prostaglandin-degrading enzyme, potentiates tissue regeneration in multiple organs in mice. In a chemical screen, we identify a small-molecule inhibitor of 15-PGDH (SW033291) that increases prostaglandin PGE2 levels in bone marrow and other tissues. SW033291 accelerates hematopoietic recovery in mice receiving a bone marrow transplant. The same compound also promotes tissue regeneration in mouse models of colon and liver injury. Tissues from 15-PGDH knockout mice demonstrate similar increased regenerative capacity. Thus, 15-PGDH inhibition may be a valuable therapeutic strategy for tissue regeneration in diverse clinical contexts.

  8. Reduced antioxidant level and increased oxidative damage in intact liver lobes during ischaemia-reperfusion

    PubMed Central

    Váli, László; Taba, Gabriella; Szentmihályi, Klára; Fébel, Hedvig; Kurucz, Tímea; Pallai, Zsolt; Kupcsulik, Péter; Blázovics, Anna

    2006-01-01

    AIM: To determine whether increased blood flow of the liver can cause oxidative stress and hepatocyte damage, and to elaborate methods suitable for measuring the antioxidant defence during hepatic surgery on rat model. METHODS: In nembutal narcosis, the left lateral and the medial lobes of the liver were clipped for 45 min to make the total blood supply flow through the other lobes. Total antioxidant status, glutathione peroxidase and superoxide dysmutase activity, as well as the concentrations of diene conjugates and free sulphydril groups, H-donating ability and reducing power of the liver samples were determined. Chemiluminescent intensity of the liver was also measured. Metal ions (Al, Ca, Cu, Fe, Mg, Mn, Zn) and P and S concentrations of the liver were determined with an inductively coupled plasma optical emission spectrometer and Se content was measured by cathodic stripping voltammetry. RESULTS: Glutathione peroxidase and superoxide dysmutase activities of the liver decreased significantly in the hyperemia group compared to those observed in the sham operated group. The level of total antioxidant status was also significantly lower in the hyperemia group. H-donating ability, reducing power and free sulphydril group concentration showed the same tendency. A significant correlation (P<0.05) was found between the changes in non-specific antioxidant activities. This pointed to simultaneous activity of the antioxidant defence system. Al, Cu, Mn, Zn, and S were lower in the hyperemia group than in the sham operated group when the levels of Ca, Fe, Mg, Se and P ions were higher during hyperemia. CONCLUSION: Oxidative stress is one of the main factors for the injury of intact liver lobes during ischaemia-reperfusion. PMID:16534850

  9. Increased risk of colorectal polyps in patients with non-alcoholic fatty liver disease undergoing liver transplant evaluation

    PubMed Central

    Bhatt, Birju D.; Lukose, Thresiamma; Siegel, Abby B.; Brown, Robert S.

    2015-01-01

    Background Screening colonoscopy is a standard part of the liver transplant (LT) evaluation process. We aimed to evaluate the yield of screening colonoscopy and determine whether non-alcoholic fatty liver disease (NAFLD) was associated with an increased risk of colorectal neoplasia. Methods We retrospectively assessed all patients who completed LT evaluation at our center between 1/2008-12/2012. Patients <50 years old and those without records of screening colonoscopy, or with greater than average colon cancer risk were excluded. Results A total of 1,102 patients were evaluated, 591 met inclusion criteria and were analyzed. The mean age was 60 years, 67% were male, 12% had NAFLD and 88% had other forms of chronic liver disease. Overall, 42% of patients had a polyp found on colonoscopy: 23% with adenomas, 14% with hyperplastic polyps and with 1% inflammatory polyps. In the final multivariable model controlling for age, NAFLD [odds ratio (OR) 2.41, P=0.001] and a history of significant alcohol use (OR 1.69, P=0.004) were predictive of finding a polyp on colonoscopy. In addition, NAFLD (OR 1.95, P=0.02), significant alcohol use (OR 1.70, P=0.01) and CTP class C (OR 0.57, P=0.02) were associated with adenoma, controlling for age. Conclusions Screening colonoscopy in patients awaiting LT yields a high rate of polyp (43%) and adenoma (22%) detection, perhaps preventing the accelerated progression to carcinoma that can occur in immunosuppressed post-LT patients. Patients with NAFLD may be at a ~2 fold higher risk of adenomas and should be carefully evaluated prior to LT. PMID:26487938

  10. Ageing Fxr deficient mice develop increased energy expenditure, improved glucose control and liver damage resembling NASH.

    PubMed

    Bjursell, Mikael; Wedin, Marianne; Admyre, Therése; Hermansson, Majlis; Böttcher, Gerhard; Göransson, Melker; Lindén, Daniel; Bamberg, Krister; Oscarsson, Jan; Bohlooly-Y, Mohammad

    2013-01-01

    Nuclear receptor subfamily 1, group H, member 4 (Nr1h4, FXR) is a bile acid activated nuclear receptor mainly expressed in the liver, intestine, kidney and adrenal glands. Upon activation, the primary function is to suppress cholesterol 7 alpha-hydroxylase (Cyp7a1), the rate-limiting enzyme in the classic or neutral bile acid synthesis pathway. In the present study, a novel Fxr deficient mouse line was created and studied with respect to metabolism and liver function in ageing mice fed chow diet. The Fxr deficient mice were similar to wild type mice in terms of body weight, body composition, energy intake and expenditure as well as behaviours at a young age. However, from 15 weeks of age and onwards, the Fxr deficient mice had almost no body weight increase up to 39 weeks of age mainly because of lower body fat mass. The lower body weight gain was associated with increased energy expenditure that was not compensated by increased food intake. Fasting levels of glucose and insulin were lower and glucose tolerance was improved in old and lean Fxr deficient mice. However, the Fxr deficient mice displayed significantly increased liver weight, steatosis, hepatocyte ballooning degeneration and lobular inflammation together with elevated plasma levels of ALT, bilirubin and bile acids, findings compatible with non-alcoholic steatohepatitis (NASH) and cholestasis. In conclusion, ageing Fxr deficient mice display late onset leanness associated with elevated energy expenditure and improved glucose control but develop severe NASH-like liver pathology.

  11. Glutathione transferases P1/P2 regulate the timing of signaling pathway activations and cell cycle progression during mouse liver regeneration.

    PubMed

    Pajaud, J; Ribault, C; Ben Mosbah, I; Rauch, C; Henderson, C; Bellaud, P; Aninat, C; Loyer, P; Morel, F; Corlu, A

    2015-01-15

    Glutathione transferases (GST) are phase II enzymes catalyzing the detoxification of endogenous noxious compounds and xenobiotics. They also regulate phosphorylation activities of MAPKinases in a catalytic-independent manner. Previous studies have demonstrated the regulation of JNK-dependent pathway by GSTP1/2. Considering the crucial role of JNK in the early steps of the hepatocyte cell cycle, we sought to determine whether GSTP1/2 were essential for hepatocyte proliferation following partial hepatectomy (PH). Using a conventional double knockout mouse model for the Gstp1 and Gstp2 genes, we found that the lack of GSTP1/P2 reduced the rate of DNA replication and mitotic index during the first wave of hepatocyte proliferation. The lowered proliferation was associated with the decrease in TNFalpha and IL-6 plasma concentrations, reduced hepatic HGF expression and delayed and/or altered activation of STAT3, JNK and ERK1/2 signaling pathways. In addition, the expression and/or activation of cell cycle regulators such as Cyclin D1, CDK4, E2F1 and MCM7 was postponed demonstrating that the absence of GSTP1/2 delayed the entry into and progression through the G1 phase of the cell cycle and impaired the synchrony of proliferation in hepatocytes following PH. Furthermore, while JNK and its downstream targets c-Jun and ATF2 were activated during the early steps of the liver regeneration in wild-type animals, the constitutively active JNK found in the quiescent liver of Gstp1/2 knockout mice underwent a decrease in its activity after PH. Transient induction of antioxidant enzymes and nitric oxide synthase were also delayed or repressed during the regenerative response. Altogether our results demonstrate that GSTP1/2 are a critical regulators of hepatocyte proliferation in the initial phases of liver regeneration.

  12. Glutathione transferases P1/P2 regulate the timing of signaling pathway activations and cell cycle progression during mouse liver regeneration

    PubMed Central

    Pajaud, J; Ribault, C; Ben Mosbah, I; Rauch, C; Henderson, C; Bellaud, P; Aninat, C; Loyer, P; Morel, F; Corlu, A

    2015-01-01

    Glutathione transferases (GST) are phase II enzymes catalyzing the detoxification of endogenous noxious compounds and xenobiotics. They also regulate phosphorylation activities of MAPKinases in a catalytic-independent manner. Previous studies have demonstrated the regulation of JNK-dependent pathway by GSTP1/2. Considering the crucial role of JNK in the early steps of the hepatocyte cell cycle, we sought to determine whether GSTP1/2 were essential for hepatocyte proliferation following partial hepatectomy (PH). Using a conventional double knockout mouse model for the Gstp1 and Gstp2 genes, we found that the lack of GSTP1/P2 reduced the rate of DNA replication and mitotic index during the first wave of hepatocyte proliferation. The lowered proliferation was associated with the decrease in TNFalpha and IL-6 plasma concentrations, reduced hepatic HGF expression and delayed and/or altered activation of STAT3, JNK and ERK1/2 signaling pathways. In addition, the expression and/or activation of cell cycle regulators such as Cyclin D1, CDK4, E2F1 and MCM7 was postponed demonstrating that the absence of GSTP1/2 delayed the entry into and progression through the G1 phase of the cell cycle and impaired the synchrony of proliferation in hepatocytes following PH. Furthermore, while JNK and its downstream targets c-Jun and ATF2 were activated during the early steps of the liver regeneration in wild-type animals, the constitutively active JNK found in the quiescent liver of Gstp1/2 knockout mice underwent a decrease in its activity after PH. Transient induction of antioxidant enzymes and nitric oxide synthase were also delayed or repressed during the regenerative response. Altogether our results demonstrate that GSTP1/2 are a critical regulators of hepatocyte proliferation in the initial phases of liver regeneration. PMID:25590808

  13. Increased hepcidin in transferrin-treated thalassemic mice correlates with increased liver BMP2 expression and decreased hepatocyte ERK activation

    PubMed Central

    Chen, Huiyong; Choesang, Tenzin; Li, Huihui; Sun, Shuming; Pham, Petra; Bao, Weili; Feola, Maria; Westerman, Mark; Li, Guiyuan; Follenzi, Antonia; Blanc, Lionel; Rivella, Stefano; Fleming, Robert E.; Ginzburg, Yelena Z.

    2016-01-01

    Iron overload results in significant morbidity and mortality in β-thalassemic patients. Insufficient hepcidin is implicated in parenchymal iron overload in β-thalassemia and approaches to increase hepcidin have therapeutic potential. We have previously shown that exogenous apo-transferrin markedly ameliorates ineffective erythropoiesis and increases hepcidin expression in Hbbth1/th1 (thalassemic) mice. We utilize in vivo and in vitro systems to investigate effects of exogenous apo-transferrin on Smad and ERK1/2 signaling, pathways that participate in hepcidin regulation. Our results demonstrate that apo-transferrin increases hepcidin expression in vivo despite decreased circulating and parenchymal iron concentrations and unchanged liver Bmp6 mRNA expression in thalassemic mice. Hepatocytes from apo-transferrin-treated mice demonstrate decreased ERK1/2 pathway and increased serum BMP2 concentration and hepatocyte BMP2 expression. Furthermore, hepatocyte ERK1/2 phosphorylation is enhanced by neutralizing anti-BMP2/4 antibodies and suppressed in vitro in a dose-dependent manner by BMP2, resulting in converse effects on hepcidin expression, and hepatocytes treated with MEK/ERK1/2 inhibitor U0126 in combination with BMP2 exhibit an additive increase in hepcidin expression. Lastly, bone marrow erythroferrone expression is normalized in apo-transferrin treated thalassemic mice but increased in apo-transferrin injected wild-type mice. These findings suggest that increased hepcidin expression after exogenous apo-transferrin is in part independent of erythroferrone and support a model in which apo-transferrin treatment in thalassemic mice increases BMP2 expression in the liver and other organs, decreases hepatocellular ERK1/2 activation, and increases nuclear Smad to increase hepcidin expression in hepatocytes. PMID:26635037

  14. Polμ Deficiency Increases Resistance to Oxidative Damage and Delays Liver Aging

    PubMed Central

    Escudero, Beatriz; Lucas, Daniel; Albo, Carmen; Dhup, Suveera; Bacher, Jeff W.; Sánchez-Muñoz, Aránzazu; Fernández, Margarita; Rivera-Torres, José; Carmona, Rosa M.; Fuster, Encarnación; Carreiro, Candelas; Bernad, Raquel; González, Manuel A.; Andrés, Vicente; Blanco, Luis; Roche, Enrique; Fabregat, Isabel; Samper, Enrique; Bernad, Antonio

    2014-01-01

    Polμ is an error-prone PolX polymerase that contributes to classical NHEJ DNA repair. Mice lacking Polμ (Polμ−/−) show altered hematopoiesis homeostasis and DSB repair and a more pronounced nucleolytic resection of some V(D)J junctions. We previously showed that Polμ−/− mice have increased learning capacity at old ages, suggesting delayed brain aging. Here we investigated the effect of Polμ−/− deficiency on liver aging. We found that old Polμ−/− mice (>20 month) have greater liver regenerative capacity compared with wt animals. Old Polμ−/− liver showed reduced genomic instability and increased apoptosis resistance. However, Polμ−/− mice did not show an extended life span and other organs (e.g., heart) aged normally. Our results suggest that Polμ deficiency activates transcriptional networks that reduce constitutive apoptosis, leading to enhanced liver repair at old age. PMID:24691161

  15. Intense exercise increases protein oxidation in spleen and liver of mice.

    PubMed

    Kobayashi, Yukiko; Nakatsuji, Aki; Aoi, Wataru; Wada, Sayori; Kuwahata, Masashi; Kido, Yasuhiro

    2014-01-01

    Studies have indicated that sports anemia is mainly associated with intravascular hemolysis induced by exercise. We hypothesized that such exercise-induced hemolysis leads to oxidative damage due to an increase in free iron caused by hematocyte destruction. Thirty-one male ICR mice were randomly divided into 3 groups: a rested control group, an intense-exercise group, and a group rested for 24 hours after intense exercise. The serum haptoglobin level of the intense-exercise group decreased compared with that of the rested control group, suggesting hemolysis. Tissue iron and protein carbonyl levels in the liver were increased after exercise, and the protein carbonyl level in the spleen on the day after exercise was significantly increased compared with that of the resting state. These results suggest that the spleen and liver, where extravascular hemolysis occurs, were subjected to oxidative modification by the free iron, which was released from large numbers of hemocytes that were destroyed due to the intense exercise.

  16. Metformin Increases Cortisol Regeneration by 11βHSD1 in Obese Men With and Without Type 2 Diabetes Mellitus

    PubMed Central

    Anderson, Anna J.; Andrew, Ruth; Homer, Natalie Z.; Jones, Gregory C.; Smith, Kenneth; Livingstone, Dawn E.; Walker, Brian R.

    2016-01-01

    Context: The mechanism of action of metformin remains unclear. Given the regulation of the cortisol-regenerating enzyme 11βhydroxysteroid dehydrogenase 1 (11βHSD1) by insulin and the limited efficacy of selective 11βHSD1 inhibitors to lower blood glucose when co-prescribed with metformin, we hypothesized that metformin reduces 11βHSD1 activity. Objective: To determine whether metformin regulates 11βHSD1 activity in vivo in obese men with and without type 2 diabetes mellitus. Design: Double-blind, randomized, placebo-controlled, crossover study. Setting: A hospital clinical research facility. Participants: Eight obese nondiabetic (OND) men and eight obese men with type 2 diabetes (ODM). Intervention: Participants received 28 days of metformin (1 g twice daily), placebo, or (in the ODM group) gliclazide (80 mg twice daily) in random order. A deuterated cortisol infusion at the end of each phase measured cortisol regeneration by 11βHSD1. Oral cortisone was given to measure hepatic 11βHSD1 activity in the ODM group. The effect of metformin on 11βHSD1 was also assessed in human hepatocytes and Simpson-Golabi-Behmel syndrome adipocytes. Main Outcome Measures: The effect of metformin on whole-body and hepatic 11βHSD1 activity. Results: Whole-body 11βHSD1 activity was approximately 25% higher in the ODM group than the OND group. Metformin increased whole-body cortisol regeneration by 11βHSD1 in both groups compared with placebo and gliclazide and tended to increase hepatic 11βHSD1 activity. In vitro, metformin did not increase 11βHSD1 activity in hepatocytes or adipocytes. Conclusions: Metformin increases whole-body cortisol generation by 11βHSD1 probably through an indirect mechanism, potentially offsetting other metabolic benefits of metformin. Co-prescription with metformin should provide a greater target for selective 11βHSD1 inhibitors. PMID:27459533

  17. Increased estrogen sulfation of estradiol 17beta-D-glucuronide in metastatic tumor rat livers.

    PubMed

    Sun, Huadong; Liu, Lichuan; Pang, K Sandy

    2006-11-01

    Changes in the disposition of estradiol 17beta-d-glucuronide (E(2)17G), a substrate of the organic anion-transporting polypeptide family (Oatp) and multidrug resistance-associated protein 2 (Mrp2), were examined in livers of male Wag/Rij rats that were injected with CC531 cells intraportally to induce metastatic tumors (n = 5) or with phosphate-buffered saline for sham-operated controls (n = 4). Multiple indicator dilution, single-pass liver perfusions revealed extremely high influx clearances of [(3)H]E(2)17G (>190 ml/min) in both groups. In recirculating liver perfusions, [(3)H]E(2)17G decayed monoexponentially in the reservoir perfusate, and the total (9.19 +/- 1.33 versus 8.18 +/- 0.94 ml/min) and biliary (4.94 +/- 1.07 versus 4.60 +/- 0.86 ml/min) clearances were similar in both groups (P > 0.05). The metabolic clearance of E(2)17G was higher in the tumor group (4.60 +/- 0.64 versus 3.23 +/- 0.23 ml/min, P < 0.05). E(2)3S17G, the 3-sulfate metabolite, whose identity was confirmed by mass spectrometry, appeared only in bile and not perfusate. Liver microsomal incubations of E(2)3(35)S17G and [(3)H]estrone sulfate revealed similar sulfatase activities between the tumor and sham livers, albeit the activities were much lower for E(2)3(35)S17G. Oatp1a1 and Oatp1b2 protein expression in liver membrane fragments was reduced by 42% and 38%, respectively, whereas that of cytosolic estrogen sulfotransferase (Sult1e1) was significantly increased (41%) with tumor (P < 0.05). All of the observations were captured by modeling. From modeling, we showed that reduction of the high influx clearance (546 to 283 ml/min) failed to lower the total clearance of E(2)17G, whereas up-regulation of Sult1e1 increased the E(2)17G sulfation clearance (2.56 to 3.69 ml/min) in livers with metastatic tumors. PMID:16895976

  18. Quantification of Hepatic Vascular and Parenchymal Regeneration in Mice

    PubMed Central

    Xie, Chichi; Schwen, Lars Ole; Wei, Weiwei; Schenk, Andrea; Zafarnia, Sara; Gremse, Felix; Dahmen, Uta

    2016-01-01

    Background Liver regeneration consists of cellular proliferation leading to parenchymal and vascular growth. This study complements previous studies on cellular proliferation and weight recovery by (1) quantitatively describing parenchymal and vascular regeneration, and (2) determining their relationship. Both together are needed to (3) characterize the underlying growth pattern. Methods Specimens were created by injecting a polymerizing contrast agent in either portal or hepatic vein in normal or regenerating livers after 70% partial hepatectomy. 3D image data were obtained through micro-CT scanning. Parenchymal growth was assessed by determining weight and volume of the regenerating liver. Vascular growth was described by manually determined circumscribed parameters (maximal vessel length and radius of right inferior portal/hepatic vein), automatically determined cumulative parameters (total edge length and total vascular volume), and parameters describing vascular density (total edge length/volume, vascular volume fraction). The growth pattern was explored by comparing the relative increase of these parameters to the increase expected in case of isotropic expansion. Results Liver volume recovery paralleled weight recovery and reached 90% of the original liver volume within 7 days. Comparing radius-related vascular parameters immediately after surgical resection and after virtual resection in-silico revealed a slight increase, possibly reflecting the effect of resection-induced portal hyperperfusion. Comparing length-related parameters between post-operative day 7 and after virtual resection showed similar vascular growth in both vascular systems investigated. In contrast, radius-related parameters increased slightly more in the portal vein. Despite the seemingly homogeneous 3D growth, the observed vascular parameters were not compatible with the hypothesis of isotropic expansion of liver parenchyma and vascular structures. Conclusion We present an approach for

  19. Liver.

    PubMed

    Kim, W R; Lake, J R; Smith, J M; Skeans, M A; Schladt, D P; Edwards, E B; Harper, A M; Wainright, J L; Snyder, J J; Israni, A K; Kasiske, B L

    2016-01-01

    The median waiting time for patients with MELD ≥ 35 decreased from 18 days in 2012 to 9 days in 2014, after implementation of the Share 35 policy in June 2013. Similarly, mortality among candidates listed with MELD ≥ 35 decreased from 366 per 100 waitlist years in 2012 to 315 in 2014. The number of new active candidates added to the pediatric liver transplant waiting list in 2014 was 655, down from a peak of 826 in 2005. The number of prevalent candidates (on the list on December 31 of the given year) continued to decline, 401 active and 173 inactive. The number of deceased donor pediatric liver transplants peaked at 542 in 2008 and was 478 in 2014. The number of living donor liver pediatric transplants was 52 in 2014; most were from donors closely related to the recipients. Graft survival continued to improve among pediatric recipients of deceased donor and living donor livers. PMID:26755264

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

    PubMed Central

    Aryal, Bibek; Shimizu, Toshiaki; Kadono, Jun; Furoi, Akira; Komokata, Teruo; Inoue, Maki; Ikeda, Shunichiro; Fukukura, Yoshihiko; Nakamura, Masatoshi; Yamakuchi, Munekazu; Hashiguchi, Teruto; Imoto, Yutaka

    2016-01-01

    Background 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. Material and Methods 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. Results 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. Conclusion IP VEGF-A is overexpressed during later phase of LR suggesting its implications in inducing angiogenesis during LR. PMID:26930285

  1. Increased activity of the complement system in the liver of patients with alcoholic hepatitis.

    PubMed

    Shen, Hong; French, Barbara A; Liu, Hui; Tillman, Brittany C; French, Samuel W

    2014-12-01

    Inflammation has been suggested as a mechanism underlying the development of alcoholic hepatitis (AH). The activation of the complement system plays an important role in inflammation. Although it has been shown that ethanol-induced activation of the complement system contributes to the pathophysiology of ethanol-induced liver injury in mice, whether ethanol consumption activates the complement system in the human liver has not been investigated. Using antibodies against C1q, C3, and C5, the immunoreactivity of the complement system in patients with AH was examined by immunohistochemistry and quantified by morphometric image analysis. The immunoreactivity intensity of C1q, C3, and C5 in patients with AH was significantly higher than that seen in normal controls. Further, the gene expression of C1q, C3, and C5 was examined using real-time PCR. There were increases in the levels of C1q and C5, but not C3 mRNA in AH. Moreover, the immunoreactivity of C5a receptor (C5aR) also increased in AH. To explore the functional implication of the activation of the complement system in AH, we examined the colocalization of C5aR in Mallory-Denk bodies (MDBs) forming balloon hepatocytes. C5aR was focally overexpressed in the MDB forming cells. Collectively, our study suggests that alcohol consumption increases the activity of the complement system in the liver cells, which contributes to the inflammation-associated pathogenesis of AH.

  2. Are the increases in local tumour necrosis factor and lipid peroxidation observed in pre-starved mice infected with Salmonella typhimurium markers of increased liver damage?

    PubMed

    Rishi, Praveen; Kaur, Harsimran; Tirkey, Naveen; Chopra, Kanwaljit; Bharrhan, Sushma; Chanana, Vishal; Koul, Ashwani

    2006-06-01

    Pathogenic microorganisms are known to sense and process signals within their hosts, including those resulting from starvation. Therefore, an attempt was made to evaluate the extent and the possible underlying mechanism of Salmonella typhimurium-induced hepatic damage using pre-starved laboratory mice. The following parameters were analysed, comparing control, fed infected, starved, and starved infected mice: the bacterial load in the liver, fluctuations in liver-derived enzymes alanine-aminotransferase and aspartate-aminotransferase, histopathological changes, lipid peroxidation as well as estimation of reduced glutathione, superoxide dismutase and catalase, along with the TNF content in livers. The number of bacterial cells recovered from starved infected livers at 3 days post-S. typhimurium inoculation was comparable to the number recovered from fed infected livers at 5 days post-Salmonella inoculation, indicating an early increase in the development of the bacteria in starved mice. A marked elevation in liver-derived enzymes in mouse serum and significant histopathological changes are markers of liver damage of higher amplitude in starved infected mice. Analysis of the liver indicated a significant increase in lipid peroxidation in starved infected mice compared to their control counterparts, a process coupled with increased TNF level. Although the reduced glutathione levels showed a marked increase in the starved infected mice, there was a significant decrease in superoxide dismutase and catalase activities in this group.

  3. Increasing Whole Grain Intake as Part of Prevention and Treatment of Nonalcoholic Fatty Liver Disease

    PubMed Central

    Ross, Alastair B.; Godin, Jean-Philippe; Minehira, Kaori; Kirwan, John P.

    2013-01-01

    In conjunction with the rise in rates of obesity, there has been an increase in the rate of nonalcoholic fatty liver disease (NAFLD). While NAFLD at least partially originates from poor diet, there is a lack of nutritional recommendations for patients with suspected or confirmed diagnosis of NAFLD, beyond eating a healthy diet, increasing physical activity, and emphasising weight loss. The limited current literature suggests that there may be opportunities to provide more tailored dietary advice for people diagnosed with or at risk of NAFLD. Epidemiological studies consistently find associations between whole grain intake and a reduced risk of obesity and related diseases, yet no work has been done on the potential of whole grains to prevent and/or be a part of the treatment for fatty liver diseases. In this review, we examine the potential and the current evidence for whole grains having an impact on NAFLD. Due to their nutrient and phytochemical composition, switching from consuming mainly refined grains to whole grains should be considered as part of the nutritional guidelines for patients diagnosed with or at risk for fatty liver disease. PMID:23762052

  4. Aging increases mitochondrial DNA damage and oxidative stress in liver of rhesus monkeys

    PubMed Central

    Castro, María del R.; Suarez, Edu; Kraiselburd, Edmundo; Isidro, Angel; Paz, José; Ferder, León; Ayala-Torres, Sylvette

    2013-01-01

    While the mechanisms of cellular aging remain controversial, a leading hypothesis is that mitochondrial oxidative stress and mitochondrial dysfunction play a critical role in this process. Here, we provide data in aging rhesus macaques supporting the hypothesis that increased oxidative stress is a major characteristic of aging and may be responsible for the age-associated increase in mitochondrial dysfunction. We measured mitochondrial DNA (mtDNA) damage by quantitative PCR in liver and peripheral blood mononuclear cells of young, middle age, and old monkeys and show that older monkeys have increases in the number of mtDNA lesions. There was a direct correlation between the amount of mtDNA lesions and age, supporting the role of mtDNA damage in the process of aging. Liver from older monkeys showed significant increases in lipid peroxidation, protein carbonylations and reduced antioxidant enzyme activity. Similarly, peripheral blood mononuclear cells from the middle age group showed increased levels in carbonylated proteins, indicative of high levels of oxidative stress. Together, these results suggest that the aging process is associated with defective mitochondria, where increased production of reactive oxygen species results in extensive damage at the mtDNA and protein levels. This study provides valuable data based on the rhesus macaque model further validating age-related mitochondrial functional decline with increasing age and suggesting that mtDNA damage might be a good biomarker of aging. PMID:22027539

  5. Aging and liver disease

    PubMed Central

    Kim, Hee; Kisseleva, Tatiana; Brenner, David A.

    2016-01-01

    Purpose of review Aging is a condition in which a person gradually loses the ability to maintain homeostasis, due to structural alteration or dysfunction. Aging is a major risk factor for most chronic diseases. As the liver has a remarkable ability to regenerate, this review assessed the effect of aging on clinical liver disease with references to preclinical models when relevant to pathogenesis. Recent findings Aging has been shown to not only enhance vulnerability to acute liver injury but also increase susceptibility of the fibrotic response. Aging is associated with the severity and poor prognosis of various liver diseases including nonalcoholic fatty liver disease, alcoholic liver disease, hepatitis C, and liver transplantation. Summary Treatment of older patients with liver disease may require different or longer interventions. Transplantation of an older liver will be less tolerant of subsequent injury. Future studies are needed to understand more about the molecular mechanism of aging and contribute to the development of a noble treatment strategy that can block the progression of aging-induced liver diseases. PMID:25850346

  6. Increased childhood liver cancer mortality and arsenic in drinking water in Northern Chile

    PubMed Central

    Liaw, Jane; Marshall, Guillermo; Yuan, Yan; Ferreccio, Catterina; Steinmaus, Craig; Smith, Allan H.

    2009-01-01

    Arsenic in drinking water is an established cause of lung, bladder and skin cancers in adults, and may also cause adult kidney and liver cancer. Some evidence for these effects originated from Region II of Chile which had a period of elevated arsenic levels in drinking water, in particular from 1958 to 1970. This unique exposure scenario provides a rare opportunity to investigate the effects of early-life arsenic exposure on childhood mortality; to our knowledge, this is the first study of childhood cancer mortality and high concentrations of arsenic in drinking water. In this paper, we compare cancer mortality rates under the age of 20 in Region II during 1950–2000 with those of unexposed Region V, dividing subjects into those born before, during or after the peak exposure period. Mortality from the most common childhood cancers, leukemia and brain cancer, were not increased in the exposed population. However, we found childhood liver cancer mortality occurred at higher rates than expected; for those exposed as young children liver cancer mortality between ages 0–19 was especially high: the relative risk (RR) for males born during this period was 8.9 (95% CI 1.7–45.8; p=0.009), for females the corresponding RR was 14.1 (95% CI 1.6–126; p=0.018), and for males and females pooled, the RR was 10.6 (95% CI 2.9–39.2; p<0.001). These findings suggest exposure to arsenic in drinking water during early childhood may result in an increase in childhood liver cancer mortality. PMID:18708388

  7. Increased childhood liver cancer mortality and arsenic in drinking water in northern Chile.

    PubMed

    Liaw, Jane; Marshall, Guillermo; Yuan, Yan; Ferreccio, Catterina; Steinmaus, Craig; Smith, Allan H

    2008-08-01

    Arsenic in drinking water is an established cause of lung, bladder, and skin cancers in adults and may also cause adult kidney and liver cancers. Some evidence for these effects originated from region II of Chile, which had a period of elevated arsenic levels in drinking water, in particular from 1958 to 1970. This unique exposure scenario provides a rare opportunity to investigate the effects of early-life arsenic exposure on childhood mortality; to our knowledge, this is the first study of childhood cancer mortality and high concentrations of arsenic in drinking water. In this article, we compare cancer mortality rates under the age of 20 in region II during 1950 to 2000 with those of unexposed region V, dividing subjects into those born before, during, or after the peak exposure period. Mortality from the most common childhood cancers, leukemia and brain cancer, was not increased in the exposed population. However, we found that childhood liver cancer mortality occurred at higher rates than expected. For those exposed as young children, liver cancer mortality between ages 0 and 19 was especially high: the relative risk (RR) for males born during this period was 8.9 [95% confidence interval (95% CI), 1.7-45.8; P = 0.009]; for females, the corresponding RR was 14.1 (95% CI, 1.6-126; P = 0.018); and for males and females pooled, the RR was 10.6 (95% CI, 2.9-39.2; P < 0.001). These findings suggest that exposure to arsenic in drinking water during early childhood may result in an increase in childhood liver cancer mortality.

  8. Cannabidiol protects liver from binge alcohol-induced steatosis by mechanisms including inhibition of oxidative stress and increase in autophagy.

    PubMed

    Yang, Lili; Rozenfeld, Raphael; Wu, Defeng; Devi, Lakshmi A; Zhang, Zhenfeng; Cederbaum, Arthur

    2014-03-01

    Acute alcohol drinking induces steatosis, and effective prevention of steatosis can protect liver from progressive damage caused by alcohol. Increased oxidative stress has been reported as one mechanism underlying alcohol-induced steatosis. We evaluated whether cannabidiol, which has been reported to function as an antioxidant, can protect the liver from alcohol-generated oxidative stress-induced steatosis. Cannabidiol can prevent acute alcohol-induced liver steatosis in mice, possibly by preventing the increase in oxidative stress and the activation of the JNK MAPK pathway. Cannabidiol per se can increase autophagy both in CYP2E1-expressing HepG2 cells and in mouse liver. Importantly, cannabidiol can prevent the decrease in autophagy induced by alcohol. In conclusion, these results show that cannabidiol protects mouse liver from acute alcohol-induced steatosis through multiple mechanisms including attenuation of alcohol-mediated oxidative stress, prevention of JNK MAPK activation, and increasing autophagy.

  9. Administration of Escherichia coli endotoxin to rat increases liver mass and hepatocyte volume in vivo.

    PubMed Central

    Qian, D; Brosnan, J T

    1996-01-01

    We have established, in vivo, an increase in liver mass and hepatocyte volume after a single intraperitoneal administration, to fasted rats, of Escherichia coli lipopolysaccharide (0127:B8) at 3 mg/kg. The phenomenon was time- and dose-dependent and could be prevented by treatment with polyclonal antiserum against tumour necrosis factor-alpha (TNF-alpha) before the endotoxin injection. Endotoxin caused an increase of 26% in the hepatic mass compared with fasted controls at 24 h. An increase of 27% in the hepatic water content underlay the altered hepatic mass which could not be accounted for by a change in the volume of hepatic blood and/or interstitial fluid (measured in vivo), suggesting an expansion in the hepatocellular volume. This is supported by an increase of 25% in the K+ content of the endotoxic livers. Morphometric study confirmed a 15% increase in hepatocyte volume after endotoxin administration. The data are discussed in the light of possible metabolic effects of increased hepatocyte volume. PMID:8573081

  10. Increased Expression of TGF-β1 in Correlation with Liver Fibrosis during Echinococcus granulosus Infection in Mice.

    PubMed

    Liu, Yumei; Abudounnasier, Gulizhaer; Zhang, Taochun; Liu, Xuelei; Wang, Qian; Yan, Yi; Ding, Jianbing; Wen, Hao; Yimiti, Delixiati; Ma, Xiumin

    2016-08-01

    To investigate the potential role of transforming growth factor (TGF)-β1 in liver fibrosis during Echinococcus granulosus infection, 96 BALB/c mice were randomly divided into 2 groups, experimental group infected by intraperitoneal injection with a metacestode suspension and control group given sterile physiological saline. The liver and blood samples were collected at days 2, 8, 30, 90, 180, and 270 post infection (PI), and the expression of TGF-β1 mRNA and protein was determined by real-time quantitative RT-PCR and ELISA, respectively. We also evaluated the pathological changes in the liver during the infection using hematoxylin and eosin (H-E) and Masson staining of the liver sections. Pathological analysis of H-E stained infected liver sections revealed liver cell edema, bile duct proliferation, and structural damages of the liver as evidenced by not clearly visible lobular architecture of the infected liver, degeneration of liver cell vacuoles, and infiltration of lymphocytes at late stages of infection. The liver tissue sections from control mice remained normal. Masson staining showed worsening of liver fibrosis at the end stages of the infection. The levels of TGF-β1 did not show significant changes at the early stages of infection, but there were significant increases in the levels of TGF-β1 at the middle and late stages of infection (P<0.05). RT-PCR results showed that, when compared with the control group, TGF-β1 mRNA was low and comparable with that in control mice at the early stages of infection, and that it was significantly increased at day 30 PI and remained at high levels until day 270 PI (P<0.05). The results of this study suggested that increased expression of TGF-β1 during E. granulosus infection may play a significant role in liver fibrosis associated with E. granulosus infection.

  11. Increased Expression of TGF-β1 in Correlation with Liver Fibrosis during Echinococcus granulosus Infection in Mice.

    PubMed

    Liu, Yumei; Abudounnasier, Gulizhaer; Zhang, Taochun; Liu, Xuelei; Wang, Qian; Yan, Yi; Ding, Jianbing; Wen, Hao; Yimiti, Delixiati; Ma, Xiumin

    2016-08-01

    To investigate the potential role of transforming growth factor (TGF)-β1 in liver fibrosis during Echinococcus granulosus infection, 96 BALB/c mice were randomly divided into 2 groups, experimental group infected by intraperitoneal injection with a metacestode suspension and control group given sterile physiological saline. The liver and blood samples were collected at days 2, 8, 30, 90, 180, and 270 post infection (PI), and the expression of TGF-β1 mRNA and protein was determined by real-time quantitative RT-PCR and ELISA, respectively. We also evaluated the pathological changes in the liver during the infection using hematoxylin and eosin (H-E) and Masson staining of the liver sections. Pathological analysis of H-E stained infected liver sections revealed liver cell edema, bile duct proliferation, and structural damages of the liver as evidenced by not clearly visible lobular architecture of the infected liver, degeneration of liver cell vacuoles, and infiltration of lymphocytes at late stages of infection. The liver tissue sections from control mice remained normal. Masson staining showed worsening of liver fibrosis at the end stages of the infection. The levels of TGF-β1 did not show significant changes at the early stages of infection, but there were significant increases in the levels of TGF-β1 at the middle and late stages of infection (P<0.05). RT-PCR results showed that, when compared with the control group, TGF-β1 mRNA was low and comparable with that in control mice at the early stages of infection, and that it was significantly increased at day 30 PI and remained at high levels until day 270 PI (P<0.05). The results of this study suggested that increased expression of TGF-β1 during E. granulosus infection may play a significant role in liver fibrosis associated with E. granulosus infection. PMID:27658605

  12. Increased Expression of TGF-β1 in Correlation with Liver Fibrosis during Echinococcus granulosus Infection in Mice

    PubMed Central

    Liu, Yumei; Abudounnasier, Gulizhaer; Zhang, Taochun; Liu, Xuelei; Wang, Qian; Yan, Yi; Ding, Jianbing; Wen, Hao; Yimiti, Delixiati; Ma, Xiumin

    2016-01-01

    To investigate the potential role of transforming growth factor (TGF)-β1 in liver fibrosis during Echinococcus granulosus infection, 96 BALB/c mice were randomly divided into 2 groups, experimental group infected by intraperitoneal injection with a metacestode suspension and control group given sterile physiological saline. The liver and blood samples were collected at days 2, 8, 30, 90, 180, and 270 post infection (PI), and the expression of TGF-β1 mRNA and protein was determined by real-time quantitative RT-PCR and ELISA, respectively. We also evaluated the pathological changes in the liver during the infection using hematoxylin and eosin (H-E) and Masson staining of the liver sections. Pathological analysis of H-E stained infected liver sections revealed liver cell edema, bile duct proliferation, and structural damages of the liver as evidenced by not clearly visible lobular architecture of the infected liver, degeneration of liver cell vacuoles, and infiltration of lymphocytes at late stages of infection. The liver tissue sections from control mice remained normal. Masson staining showed worsening of liver fibrosis at the end stages of the infection. The levels of TGF-β1 did not show significant changes at the early stages of infection, but there were significant increases in the levels of TGF-β1 at the middle and late stages of infection (P<0.05). RT-PCR results showed that, when compared with the control group, TGF-β1 mRNA was low and comparable with that in control mice at the early stages of infection, and that it was significantly increased at day 30 PI and remained at high levels until day 270 PI (P<0.05). The results of this study suggested that increased expression of TGF-β1 during E. granulosus infection may play a significant role in liver fibrosis associated with E. granulosus infection. PMID:27658605

  13. Increase of hepatic fat accumulation by liver specific expression of Hepatitis B virus X protein in zebrafish.

    PubMed

    Shieh, Yun-Sheng; Chang, Yin-Shan; Hong, Jiann-Ruey; Chen, Li-Je; Jou, Luen-Kuang; Hsu, Chia-Chun; Her, Guor Mour

    2010-07-01

    The pathogenesis of fatty liver disease remains largely unknown. Here, we assessed the importance of hepatic fat accumulation on the progression of hepatitis in zebrafish by liver specific expression of Hepatitis B virus X protein (HBx). Transgenic zebrafish lines, GBXs, which selectively express the GBx transgene (GFP-fused HBx gene) in liver, were established. GBX Liver phenotypes were evaluated by histopathology and molecular analysis of fatty acid (FA) metabolism-related genes expression. Most GBXs (66-81%) displayed obvious emaciation starting at 4 months old. Over 99% of the emaciated GBXs developed hepatic steatosis or steatohepatitis, which in turn led to liver hypoplasia. The liver histology of GBXs displayed steatosis, lobular inflammation, and balloon degeneration, similar to non-alcoholic steatohepatitis (NASH). Oil red O stain detected the accumulation of fatty droplets in GBXs. RT-PCR and Q-rt-PCR analysis revealed that GBx induced hepatic steatosis had significant increases in the expression of lipogenic genes, C/EBP-alpha, SREBP1, ChREBP and PPAR-gamma, which then activate key enzymes of the de novo FA synthesis, ACC1, FAS, SCD1, AGAPT, PAP and DGAT2. In addition, the steatohepatitic GBX liver progressed to liver degeneration and exhibited significant differential gene expression in apoptosis and stress. The GBX models exhibited both the genetic and functional factors involved in lipid accumulation and steatosis-associated liver injury. In addition, GBXs with transmissible NASH-like phenotypes provide a promising model for studying liver disease. PMID:20416398

  14. Increased Cell Fusion in Cerebral Cortex May Contribute to Poststroke Regeneration

    PubMed Central

    Paltsyn, Alexander; Komissarova, Svetlana; Dubrovin, Ivan; Kubatiev, Aslan

    2013-01-01

    In this study, we used a model of a hemorrhagic stroke in a motor zone of the cortex in rats at the age of 3 months The report shows that cortical neurons can fuse with oligodendrocytes. In formed binuclear cells, the nucleus of an oligodendrocyte undergoes neuron specific reprogramming. It can be confirmed by changes in chromatin structure and in size of the second nucleus, by expression of specific neuronal markers and increasing total transcription rate. The nucleus of an oligodendrocyte likely transforms into a second neuronal nucleus. The number of binuclear neurons was validated with quantitative analysis. Fusion of neurons with oligodendrocytes might be a regenerative process in general and specifically following a stroke. The appearance of additional neuronal nuclei increases the functional outcome of the population of neurons. Participation of a certain number of binuclear cells in neuronal function might compensate for a functional deficit that arises from the death of a subset of neurons. After a stroke, the number of binuclear neurons increased in cortex around the lesion zone. In this case, the rate of recovery of stroke-damaged locomotor behavior also increased, which indicates the regenerative role of fusion. PMID:23691431

  15. Increased sensitivity of apolipoprotein E knockout mice to copper-induced oxidative injury to the liver.

    PubMed

    Chen, Yuan; Li, Bin; Zhao, Ran-ran; Zhang, Hui-feng; Zhen, Chao; Guo, Li

    2015-04-10

    Apolipoprotein E (ApoE) genotypes are related to clinical presentations in patients with Wilson's disease, indicating that ApoE may play an important role in the disease. However, our understanding of the role of ApoE in Wilson's disease is limited. High copper concentration in Wilson's disease induces excessive generation of free oxygen radicals. Meanwhile, ApoE proteins possess antioxidant effects. We therefore determined whether copper-induced oxidative damage differ in the liver of wild-type and ApoE knockout (ApoE(-/-)) mice. Both wild-type and ApoE(-/-) mice were intragastrically administered with 0.2 mL of copper sulfate pentahydrate (200 mg/kg; a total dose of 4 mg/d) or the same volume of saline daily for 12 weeks, respectively. Copper and oxidative stress markers in the liver tissue and in the serum were assessed. Our results showed that, compared with the wild-type mice administered with copper, TBARS as a marker of lipid peroxidation, the expression of oxygenase-1 (HO-1), NAD(P)H dehydrogenase, and quinone 1 (NQO1) significantly increased in the ApoE(-/-) mice administered with copper, meanwhile superoxide dismutase (SOD) activity significantly decreased. Thus, it is concluded that ApoE may protect the liver from copper-induced oxidative damage in Wilson's disease.

  16. Increased sensitivity of apolipoprotein E knockout mice to copper-induced oxidative injury to the liver.

    PubMed

    Chen, Yuan; Li, Bin; Zhao, Ran-ran; Zhang, Hui-feng; Zhen, Chao; Guo, Li

    2015-04-10

    Apolipoprotein E (ApoE) genotypes are related to clinical presentations in patients with Wilson's disease, indicating that ApoE may play an important role in the disease. However, our understanding of the role of ApoE in Wilson's disease is limited. High copper concentration in Wilson's disease induces excessive generation of free oxygen radicals. Meanwhile, ApoE proteins possess antioxidant effects. We therefore determined whether copper-induced oxidative damage differ in the liver of wild-type and ApoE knockout (ApoE(-/-)) mice. Both wild-type and ApoE(-/-) mice were intragastrically administered with 0.2 mL of copper sulfate pentahydrate (200 mg/kg; a total dose of 4 mg/d) or the same volume of saline daily for 12 weeks, respectively. Copper and oxidative stress markers in the liver tissue and in the serum were assessed. Our results showed that, compared with the wild-type mice administered with copper, TBARS as a marker of lipid peroxidation, the expression of oxygenase-1 (HO-1), NAD(P)H dehydrogenase, and quinone 1 (NQO1) significantly increased in the ApoE(-/-) mice administered with copper, meanwhile superoxide dismutase (SOD) activity significantly decreased. Thus, it is concluded that ApoE may protect the liver from copper-induced oxidative damage in Wilson's disease. PMID:25749341

  17. Large intestine permeability is increased in patients with compensated liver cirrhosis.

    PubMed

    Pijls, Kirsten E; Koek, Ger H; Elamin, Elhaseen E; de Vries, Hanne; Masclee, Ad A M; Jonkers, Daisy M A E

    2014-01-01

    Intestinal barrier dysfunction, facilitating translocation of bacteria and bacterial products, plays an important role in the pathophysiology of liver cirrhosis and its complications. Increased intestinal permeability has been found in patients with liver cirrhosis, but data on small and large intestine permeability and tight junctions (TJs) in patients with compensated cirrhosis are scarce. We aimed to investigate both small and large intestine permeability in patients with stable compensated cirrhosis compared with healthy controls and evaluated the expression of TJ proteins in mucosal biopsies at duodenal and sigmoid level. Intestinal permeability was assessed in 26 patients with compensated cirrhosis and 27 matched controls using a multisugar test. Duodenal and sigmoid biopsies were available from a subgroup for analyses of gene transcription and expression of key TJ proteins by qRT-PCR and ELISA, respectively. Median 0-5-h urinary sucrose excretion and lactulose/rhamnose ratio were comparable between patients with compensated cirrhosis and controls, whereas 5-24-h urinary sucralose/erythritol ratio was increased in these patients. Downregulation of gene transcription was found for claudin-3 in duodenal biopsies and claudin-4 in sigmoid biopsies, and at the protein level occludin expression was significantly increased in both duodenal and sigmoid biopsies. This study shows that gastroduodenal and small intestine permeability are not altered, whereas large intestine permeability is increased in patients with stable compensated cirrhosis. Only limited alterations were found regarding the expression of TJ proteins in both the small and large intestine.

  18. Folate supplementation increases genomic DNA methylation in the liver of elder rats.

    PubMed

    Choi, Sang-Woon; Friso, Simonetta; Keyes, Mary K; Mason, Joel B

    2005-01-01

    The availability of folate is implicated as a determinant of DNA methylation, a functionally important feature of DNA. Nevertheless, when this phenomenon has been examined in the rodent model, the effect has not always been observed. Several reasons have been postulated for the inconsistency between studies: the rodent is less dependent on folate as a methyl source than man; juvenile animals, which most studies use, are more resistant to folate depletion than old animals; methods to measure genomic DNA methylation might not be sensitive enough to detect differences. We therefore examined the relationship between folate and genomic DNA methylation in an elder rat model with a newly developed method that can measure genomic DNA methylation sensitively and precisely. Thirty-nine 1-year-old rats were divided into three groups and fed a diet containing 0, 4.5 or 18 mumol folate/kg (folate-deplete, -replete and -supplemented groups, respectively). Rats were killed at 8 and 20 weeks. At both time points, mean liver folate concentrations increased incrementally between the folate-deplete, -replete and -supplemented rats (P for trend <0.001) and by 20 weeks hepatic DNA methylation also increased incrementally between the folate-deplete, -replete and -supplemented rats (P for trend=0.025). At both time points folate-supplemented rats had significantly increased levels of DNA methylation compared with folate-deplete rats (P<0.05). There was a strong correlation between hepatic folate concentration and genomic DNA methylation in the liver (r 0.48, P=0.004). In the liver of this animal model, dietary folate over a wide range of intakes modulates genomic DNA methylation.

  19. Splenectomy Causes 10-Fold Increased Risk of Portal Venous System Thrombosis in Liver Cirrhosis Patients

    PubMed Central

    Qi, Xingshun; Han, Guohong; Ye, Chun; Zhang, Yongguo; Dai, Junna; Peng, Ying; Deng, Han; Li, Jing; Hou, Feifei; Ning, Zheng; Zhao, Jiancheng; Zhang, Xintong; Wang, Ran; Guo, Xiaozhong

    2016-01-01

    Background Portal venous system thrombosis (PVST) is a life-threatening complication of liver cirrhosis. We conducted a retrospective study to comprehensively analyze the prevalence and risk factors of PVST in liver cirrhosis. Material/Methods All cirrhotic patients without malignancy admitted between June 2012 and December 2013 were eligible if they underwent contrast-enhanced CT or MRI scans. Independent predictors of PVST in liver cirrhosis were calculated in multivariate analyses. Subgroup analyses were performed according to the severity of PVST (any PVST, main portal vein [MPV] thrombosis >50%, and clinically significant PVST) and splenectomy. Odds ratios (ORs) and 95% confidence intervals (CIs) were reported. Results Overall, 113 cirrhotic patients were enrolled. The prevalence of PVST was 16.8% (19/113). Splenectomy (any PVST: OR=11.494, 95%CI=2.152–61.395; MPV thrombosis >50%: OR=29.987, 95%CI=3.247–276.949; clinically significant PVST: OR=40.415, 95%CI=3.895–419.295) and higher hemoglobin (any PVST: OR=0.974, 95%CI=0.953–0.996; MPV thrombosis >50%: OR=0.936, 95%CI=0.895–0.980; clinically significant PVST: OR=0.935, 95%CI=0.891–0.982) were the independent predictors of PVST. The prevalence of PVST was 13.3% (14/105) after excluding splenectomy. Higher hemoglobin was the only independent predictor of MPV thrombosis >50% (OR=0.952, 95%CI=0.909–0.997). No independent predictors of any PVST or clinically significant PVST were identified in multivariate analyses. Additionally, PVST patients who underwent splenectomy had a significantly higher proportion of clinically significant PVST but lower MELD score than those who did not undergo splenectomy. In all analyses, the in-hospital mortality was not significantly different between cirrhotic patient with and without PVST. Conclusions Splenectomy may increase by at least 10-fold the risk of PVST in liver cirrhosis independent of severity of liver dysfunction. PMID:27432511

  20. Food restriction prevents an age-associated increase in rat liver beta-adrenergic receptors

    SciTech Connect

    Dax, E.M.; Ingram, D.K.; Partilla, J.S.; Gregerman, R.I.

    1989-05-01

    In male Wistar rats fed ad libitum (24% protein, 4.5 Kcal/gm), the (/sup 125/I)iodopindolol binding capacity of the beta-adrenergic receptors in liver of 24-month-old animals is 3-4 times greater than that of 6-month-old counterparts. In rats fed the same diet, on alternate days from weaning, the receptor capacity did not increase significantly between 6 and 24 months (10.20 +/- 0.55 vs 9.20 +/- 0.72 fmol/mg) or between 24 and 30 months. This was not due to acute dietary deprivation, as rats food-restricted for only 2 weeks, at 23.5 months of age, also showed elevated receptor capacities compared to 6-month-old ad libitum fed animals. Moreover, intermittent feeding produced no significant effects among 6-month-old animals, whether restricted since weaning or for two weeks prior to sacrifice. Many biochemical parameters that decrease with aging in rats fed ad libitum are prevented by dietary restriction. Our results demonstrate that a reproducible biochemical process that increases with aging is also prevented with dietary restriction. The age-related, liver beta-receptor increase may be a potentially reliable marker for studying biochemical perturbations that modify life span.

  1. Sustained Delivery Growth Factors with Polyethyleneimine‐Modified Nanoparticles Promote Embryonic Stem Cells Differentiation and Liver Regeneration

    PubMed Central

    Wang, Meiyan; Yang, Xiaomei; Zhang, Peng; Cai, Lei; Yang, Xibin; Chen, Youwei; Jing, Yuanya; Kong, Jilie

    2016-01-01

    Stem‐cell‐derived hepatocyte transplantation is considered as a potential method for the therapy of acute and chronic liver failure. However, the low efficiency of differentiation into mature and functional hepatocytes remains a major challenge for clinical applications. By using polyethyleneimine‐modified silica nanoparticles, this study develops a system for sustained delivery of growth factors, leading to induce hepatocyte‐like cells (iHeps) from mouse embryonic stem cells (mESCs) and improve the expression of endoderm and hepatocyte‐specific genes and proteins significantly, thus producing a higher population of functional hepatocytes in vitro. When transplanted into liver‐injured mice after four weeks, mESC‐derived definitive endoderm cells treated with this delivery system show higher integration efficiency into the host liver, differentiated into iHeps in vivo and significantly restored the injured liver. Therefore, these findings reveal the multiple advantages of functionalized nanoparticles to serve as efficient delivery platforms to promote stem cell differentiation in the regenerative medicine.

  2. Phosphorylase re-expression, increase in the force of contraction and decreased fatigue following notexin-induced muscle damage and regeneration in the ovine model of McArdle disease.

    PubMed

    Howell, J McC; Walker, K R; Creed, K E; Dunton, E; Davies, L; Quinlivan, R; Karpati, G

    2014-02-01

    McArdle disease is caused by a deficiency of myophosphorylase and currently a satisfactory treatment is not available. The injection of notexin into, or the layering of notexin onto, the muscles of affected sheep resulted in necrosis followed by regeneration of muscle fibres with the expression of both non-muscle isoforms of phosphorylase within the fibres and a reduction of the amount of glycogen in the muscle with an increase in the strength of contraction and a decrease in fatiguability in the muscle fibres. The sustained re-expression of both the brain and liver isoforms of phosphorylase within the muscle fibres provides further emphasis that strategies to enhance the re-expression of these isoforms should be investigated as a possible treatment for McArdle disease.

  3. Short communication: Glutamine increases autophagy of liver cells in weaned calves.

    PubMed

    Hu, Z Y; Li, S L; Cao, Z J

    2012-12-01

    The objectives of this study were to determine the effects of an increased jugular supply of l-Gln on the autophagy of weaned calves. At 35 d of age, 24 Holstein calves (initial body weight of 50±0.5 kg; 35±2 d of age) were randomly allocated to 4 treatments, with each treatment including 5 male calves and 1 female calf. Holstein calves were assigned to treatments of (1) intravenous infusion of 2d of 0.85% NaCl (control group) (2) intravenous infusion of 8 g/d of L-Gln mixed with 2d of 0.85% NaCl solution, (3) intravenous infusion of 16 g/d of L-Gln mixed with 2d of 0.85% NaCl solution, and (4) intravenous infusion of 32 g/d of L-Gln mixed with 2d of 0.85% NaCl. The infusion was administered 2h/d for 7 consecutive days starting on d 1 after weaning. Feed and water were freely available to all calves. All calves were killed on d 7 postweaning to measure the autophagy of liver cells. The level of autophagy in liver cells was improved when the Gln infusion dose increased.

  4. Liver-Specific Inactivation of the Proprotein Convertase FURIN Leads to Increased Hepatocellular Carcinoma Growth.

    PubMed

    Declercq, Jeroen; Brouwers, Bas; Pruniau, Vincent P E G; Stijnen, Pieter; Tuand, Krizia; Meulemans, Sandra; Prat, Annik; Seidah, Nabil G; Khatib, Abdel-Majid; Creemers, John W M

    2015-01-01

    Proprotein convertases are subtilisin-like serine endoproteases that cleave and hence activate a variety of proproteins, including growth factors, receptors, metalloproteases, and extracellular matrix proteins. Therefore, it has been suggested that inhibition of the ubiquitously expressed proprotein convertase FURIN might be a good therapeutic strategy for several tumor types. Whether this is also the case for hepatocellular carcinoma (HCC) is currently not clear. In a mouse model for HCC expression of Furin was not altered in the tumors, while those of PC7, PC5/6, and PACE4 significantly decreased, at least at some time points. To investigate the impact of Furin inhibition on the development and progression of HCC in this model, Furin was genetically ablated in the liver. Furin inactivation resulted in an increased tumor mass after 5 weeks. This was not caused by decreased apoptosis, since no differences in the apoptosis index could be observed. However, it could at least partially be explained by increased hepatocyte proliferation at 5 weeks. The tumors of the Furin knockout mice were histologically similar to those in wild type mice. In conclusion, liver-specific Furin inhibition in HCC enhances the tumor formation and will not be a good therapeutic strategy for this tumor type.

  5. Utilization of Public Health Service Increased Risk Donors Yields Equivalent Outcomes in Liver Transplantation

    PubMed Central

    Hertl, M.; Chan, E. Y.

    2016-01-01

    Background. The PHS increased risk donor (IRD) is underutilized in liver transplantation. We aimed to examine the posttransplant outcomes in recipients of increased-risk organs. Methods. We analyzed 228,040 transplants in the Organ Procurement and Transplantation Network database from 2004 to 2013. Endpoints were graft failure and death. Results were controlled for demographics and comorbidities. Statistical analysis utilized Fisher's test and logistic regression. Results. 58,816 patients were identified (5,534 IRD, 53,282 non-IRD). IRDs were more frequently male (69.2% versus 58.3%, p < 0.001), younger (34 versus 39, p < 0.001), and less likely to have comorbidities (p < 0.001). Waitlist time was longer for IRD graft recipients (254 versus 238 days, p < 0.001). All outcomes were better in the IRD group. Graft failure (23.6 versus 27.3%, p < 0.001) and mortality (20.4 versus 22.3%, p = 0.001) were decreased in IRD graft recipients. However, in multivariate analysis, IRD status was not a significant indicator of outcomes. Conclusion. This is the first study to describe IRD demographics in liver transplantation. Outcomes are improved in IRD organ recipients; however, controlling for donor and recipient comorbidities, ischemia time, and MELD score, the differences lose significance. In multivariate analysis, use of IRD organs is noninferior, with similar graft failure and mortality despite the infectious risk. PMID:27777790

  6. [A case of multiple liver metastases from colon cancer treated with complete resection via two-stage hepatectomy after regeneration of the liver].

    PubMed

    Sugishita, Toshiya; Ganno, Hideaki; Hataji, Kenichiro; Ami, Katunori; Nagahama, Takeo; Fukuda, Akira; Ando, Masayuki; Arai, Kuniyoshi

    2015-01-01

    A 55-year-old woman underwent low anterior resection for sigmoid colon cancer with multiple bilobar metastases. She then received 23 courses of Leucovorin, fluorouracil, and oxaliplatin (mFOLFOX) plus bevacizumab and 13 courses of Leucovorin, fluorouracil, and irinotecan (FOLFIRI) plus bevacizumab as down staging chemotherapy. A two-stage hepatectomy was planned to avoid the risk of hepatic failure due to radial resection of bilobar metastases. Therefore, a right lobectomy was performed, and curative resection was achieved 54 days after the first hepatectomy. Two-stage hepatectomy as well as a combination of induction chemotherapy and portal vein embolization may have contributed to the improved prognosis of the initially unresectable multiple bilobar liver metastases.

  7. Increased nuclear ploidy, not cell proliferation, is sustained in the peroxisome proliferator-treated rat liver.

    PubMed

    Lalwani, N D; Dethloff, L A; Haskins, J R; Robertson, D G; de la Iglesia, F A

    1997-01-01

    Peroxisome proliferators are believed to induce liver tumors in rodents due to sustained increase in cell proliferation and oxidative stress resulting from the induction of peroxisomal enzymes. The objective of this study was to conduct a sequential analysis of the early changes in cell-cycle kinetics and the dynamics of rat liver DNA synthesis after treatment with a peroxisome proliferator. Immunofluorescent detection of proliferating cell nuclear antigen (PCNA) and bromodeoxyuridine (BrdU) incorporation into DNA during S phase we used to assess rat hepatocyte proliferation in vivo during dietary administration of Wy-14,643, a known peroxisome proliferator and hepatocarcinogen in rodents. Rats were placed on diet containing 0.1% WY-14,643 and implanted subcutaneously with 5-bromo-2'deoxyuridine containing osmotic pumps 4 days prior to being sacrificed on days 4, 11, and 25 of treatment. Isolated liver nuclei labeled with fluorscein isothiocyanate (FITC)-anti-BrdU/PI and FITC-anti-PCNA/PI were analyzed for S-phase kinetics using flow cytometry. Morphometric analysis was performed to evaluate nuclear and cell size and enumeration of BrdU labeled cells, binucleated hepatocytes, and mitotic index. The BrdU labeling index increased 2-fold in livers of Wy-14,643-treated rats at day 4, but distribution of cells in G1, S phase, and G2-M did not differ significantly from controls. PCNA-positive cells decreased from 36% on day 4 to 17% on day 25, whereas the percentage of PCNA-positive cells in controls increased 2-fold from day 4 to day 11 and remained unchanged up to day 25. The differences in the number of PCNA-positive nuclei between control and Wy-14,643-treated groups were statistically significant only on day 4. Binucleated hepatocytes, determined by morphometric analysis, increased slightly on day 25 in treated rats parallel to an increase in the percentage of cells in G2-M phase. Significant shifts were noted in nuclear diameter and nuclear area after 11 and 25

  8. Effects of preventive administration of oxidized dextran on liver injury and reparative regeneration in mice infected with influenza A/H5N1 virus.

    PubMed

    Shkurupy, V A; Potapova, O V; Sharkova, T V; Shestopalov, A M; Troitskii, A V

    2015-02-01

    Intranasal infection of outbred male mice with influenza A/H5N1 A/goose/Krasnoozerskoye/627/05 virus led to high (85%) mortality of animals. Morphological studies of liver specimens showed destructive changes in the parenchyma (93.5% hepatocytes), caused by long persistence of the virus in the liver. The virus persistence was conjugated with activation of cellular immunity, manifesting by an increase in the counts of cells with high expression of proinflammatory cytokines (TNF-α) and lysosomal enzymes (lysozyme, cathepsin D). Injections of oxidized dextran 3 and 1 days before infection reduced mortality and 2-fold attenuated destructive changes in the liver, presumably due to prevention of virus penetration into the target cells, modulation of immune reactions, and stimulation of reparative plastic processes.

  9. Effects of preventive administration of oxidized dextran on liver injury and reparative regeneration in mice infected with influenza A/H5N1 virus.

    PubMed

    Shkurupy, V A; Potapova, O V; Sharkova, T V; Shestopalov, A M; Troitskii, A V

    2015-02-01

    Intranasal infection of outbred male mice with influenza A/H5N1 A/goose/Krasnoozerskoye/627/05 virus led to high (85%) mortality of animals. Morphological studies of liver specimens showed destructive changes in the parenchyma (93.5% hepatocytes), caused by long persistence of the virus in the liver. The virus persistence was conjugated with activation of cellular immunity, manifesting by an increase in the counts of cells with high expression of proinflammatory cytokines (TNF-α) and lysosomal enzymes (lysozyme, cathepsin D). Injections of oxidized dextran 3 and 1 days before infection reduced mortality and 2-fold attenuated destructive changes in the liver, presumably due to prevention of virus penetration into the target cells, modulation of immune reactions, and stimulation of reparative plastic processes. PMID:25708331

  10. Natural Killer Cells-Produced IFN-γ Improves Bone Marrow-Derived Hepatocytes Regeneration in Murine Liver Failure Model

    PubMed Central

    Li, Lu; Zeng, Zhutian; Qi, Ziping; Wang, Xin; Gao, Xiang; Wei, Haiming; Sun, Rui; Tian, Zhigang

    2015-01-01

    Bone-marrow transplantation (BMT) can repopulate the liver through BM-derived hepatocyte (BMDH) generation, although the underlying mechanism remains unclear. Using fumarylacetoacetate hydrolase–deficient (Fah−/−) mice as a liver-failure model, we confirmed that BMDHs were generated by fusion of BM-derived CD11b+F4/80+myelomonocytes with resident Fah−/− hepatocytes. Hepatic NK cells became activated during BMDH generation and were the major IFN-γ producers. Indeed, both NK cells and IFN-γ were required for BMDH generation since WT, but not NK-, IFN-γ–, or IFN-γR1–deficient BM transplantation successfully generated BMDHs and rescued survival in Fah−/− hosts. BM-derived myelomonocytes were determined to be the IFN-γ–responding cells. The IFN-γ–IFN-γR interaction contributed to the myelomonocyte–hepatocyte fusion process, as most of the CD11b+ BMDHs in mixed BM chimeric Fah−/− hosts transplanted with a 1:1 ratio of CD45.1+ WT and CD45.2+ Ifngr1−/− BM cells were of CD45.1+ WT origin. Confirming these findings in vitro, IFN-γ dose-dependently promoted the fusion of GFP+ myelomonocytes with Fah−/− hepatocytes due to a direct effect on myelomonocytes; similar results were observed using activated NK cells. In conclusion, BMDH generation requires NK cells to facilitate myelomonocyte–hepatocyte fusion in an IFN-γ–dependent manner, providing new insights for treating severe liver failure. PMID:26345133

  11. Granzyme expression in fine-needle aspirates from liver allografts is increased during acute rejection.

    PubMed

    Kuijf, M L; Kwekkeboom, Jaap; Kuijpers, Marianne A; Willems, Marc; Zondervan, Pieter E; Niesters, Hubert G M; Hop, Wim C J; Hack, C Erik; Paavonen, Timo; Höckerstedt, Krister; Tilanus, Hugo W; Lautenschlager, Irmeli; Metselaar, Herold J; Kuijf, Mark M L

    2002-10-01

    We investigated whether determination in fine-needle aspiration biopsy (FNAB) specimens of cells expressing granzymes (Grs) and Fas ligand would provide a reliable, easy, and quantitative measure of rejection activity in the transplanted liver. Retrospectively, 13 FNAB specimens obtained during clinical acute rejection, 10 FNAB specimens obtained during subclinical rejection, 12 FNAB specimens obtained during cytomegalovirus (CMV) infection, and 26 FNAB specimens obtained in the absence of rejection or infection were included on the study. Cytospin preparations of FNAB and peripheral-blood specimens were immunocytochemically stained for Fas-ligand and Gr, and increments in the liver were calculated by subtracting frequencies of positive cells in blood from those in FNAB specimens. Only sporadically Fas ligand-expressing, but many Gr-expressing, cells were detected in FNAB specimens. Increments in Gr-positive (Gr(+)) cells were significantly greater in FNAB specimens obtained during clinical rejection (median, 70 Gr(+) cells; range, 0 to 312 Gr(+) cells; P = .006) and tended to be greater in FNAB specimens obtained during subclinical rejection (median, 62 Gr(+) cells; range, 5 to 113 Gr(+) cells; P = .09) compared with those obtained in the absence of rejection (median, 16 Gr(+) cells; range, 0 to 103 Gr(+) cells). Increments obtained during clinical or subclinical rejection did not differ from those obtained during CMV infection (median, 27 Gr(+) cells; range, 6 to 212 Gr(+) cells). With the exclusion of specimens obtained during CMV infection, the sensitivity of Gr determination in FNAB specimens for the diagnosis of acute rejection (either clinical or subclinical) was 70%, and specificity, 69%. In FNAB specimens obtained during clinical and subclinical acute rejection episodes after liver transplantation, increased numbers of Gr-expressing cells were present; in the absence of CMV infection, their quantification provides a measure for rejection activity with

  12. Bumetanide increases manganese accumulation in the brain of rats with liver damage.

    PubMed

    Montes, Sergio; Castro-Chávez, Armando; Florian-Soto, Circe; Heras-Romero, Yessica; Ríos, Camilo; Rivera-Mancía, Susana

    2016-03-01

    Hepatic encephalopathy is a common complication in cases of liver damage; it results from several factors, including the accumulation of toxic substances in the brain, e.g. manganese, ammonia and glutamine. We have previously reported that manganese favors ammonia and glutamine accumulation in the brain of cirrhotic rats, and we suggested that such effect could be mediated by manganese-elicited activation of the NKCC1 (Na(+)/K(+)/2Cl(-) cotransporter 1). To test this hypothesis, we used bumetanide, an NKCC1 blocker prescribed to treat ascites in cirrhotic patients; we expected that if NKCC1 was responsible for manganese-mediated ammonia buildup and the subsequent glutamine accumulation, bumetanide could counteract such effect and improve motor coordination. In addition, we considered essential to test the effect of bumetanide on manganese brain levels. We used a model of liver damage in rats, consisting in bile-duct ligation. Animals were exposed to manganese in the drinking water (1 mg/ml) for two weeks and ammonia in the food (20% w/w of ammonia acetate) during the second week after surgery. Bumetanide was administered intraperitoneally in the course of the ammonia treatment. We measured glutamine and manganese in three brain regions: frontal cortex, striatum and cerebellum. Bumetanide produced no effect on glutamine accumulation; however, because of bumetanide treatment, manganese was increased in the brain, and also the activity of gamma-glutamyl transferase in plasma; thus, we consider that the influence of bumetanide and similar diuretics on liver function and manganese homeostasis should be further studied. PMID:26851372

  13. MBOAT7 rs641738 increases risk of liver inflammation and transition to fibrosis in chronic hepatitis C.

    PubMed

    Thabet, Khaled; Asimakopoulos, Anastasia; Shojaei, Maryam; Romero-Gomez, Manuel; Mangia, Alessandra; Irving, William L; Berg, Thomas; Dore, Gregory J; Grønbæk, Henning; Sheridan, David; Abate, Maria Lorena; Bugianesi, Elisabetta; Weltman, Martin; Mollison, Lindsay; Cheng, Wendy; Riordan, Stephen; Fischer, Janett; Spengler, Ulrich; Nattermann, Jacob; Wahid, Ahmed; Rojas, Angela; White, Rose; Douglas, Mark W; McLeod, Duncan; Powell, Elizabeth; Liddle, Christopher; van der Poorten, David; George, Jacob; Eslam, Mohammed

    2016-01-01

    Cirrhosis likely shares common pathophysiological pathways despite arising from a variety of liver diseases. A recent GWAS identified rs641738, a polymorphism in the MBOAT7 locus, as being associated with the development of alcoholic cirrhosis. Here we explore the role of this variant on liver inflammation and fibrosis in two cohorts of patients with chronic hepatitis C. In 2,051 patients, rs641738 associated with severe hepatic inflammation and increased risk of fibrosis, as well as fast fibrosis progression. At functional level, rs641738 associated with MBOAT7 transcript and protein levels in liver and blood, and with serum inflammatory, oxidative stress and macrophage activation markers. MBOAT7 was expressed in immune cell subsets, implying a role in hepatic inflammation. We conclude that the MBOAT7 rs641738 polymorphism is a novel risk variant for liver inflammation in hepatitis C, and thereby for liver fibrosis. PMID:27630043

  14. MBOAT7 rs641738 increases risk of liver inflammation and transition to fibrosis in chronic hepatitis C

    PubMed Central

    Thabet, Khaled; Asimakopoulos, Anastasia; Shojaei, Maryam; Romero-Gomez, Manuel; Mangia, Alessandra; Irving, William L.; Berg, Thomas; Dore, Gregory J.; Grønbæk, Henning; Sheridan, David; Abate, Maria Lorena; Bugianesi, Elisabetta; Weltman, Martin; Mollison, Lindsay; Cheng, Wendy; Riordan, Stephen; Fischer, Janett; Spengler, Ulrich; Nattermann, Jacob; Wahid, Ahmed; Rojas, Angela; White, Rose; Douglas, Mark W.; McLeod, Duncan; Powell, Elizabeth; Liddle, Christopher; van der Poorten, David; George, Jacob; Eslam, Mohammed; Gallego-Duran, Rocio; Applegate, Tanya; Bassendine, Margaret; Rosso, Chiara; Mezzabotta, Lavinia; Leung, Reynold; Malik, Barbara; Matthews, Gail; Grebely, Jason; Fragomeli, Vincenzo; Jonsson, Julie R.; Santaro, Rosanna

    2016-01-01

    Cirrhosis likely shares common pathophysiological pathways despite arising from a variety of liver diseases. A recent GWAS identified rs641738, a polymorphism in the MBOAT7 locus, as being associated with the development of alcoholic cirrhosis. Here we explore the role of this variant on liver inflammation and fibrosis in two cohorts of patients with chronic hepatitis C. In 2,051 patients, rs641738 associated with severe hepatic inflammation and increased risk of fibrosis, as well as fast fibrosis progression. At functional level, rs641738 associated with MBOAT7 transcript and protein levels in liver and blood, and with serum inflammatory, oxidative stress and macrophage activation markers. MBOAT7 was expressed in immune cell subsets, implying a role in hepatic inflammation. We conclude that the MBOAT7 rs641738 polymorphism is a novel risk variant for liver inflammation in hepatitis C, and thereby for liver fibrosis. PMID:27630043

  15. Alcohol Increases Liver Progenitor Populations and Induces Disease Phenotypes in Human IPSC-Derived Mature Stage Hepatic Cells.

    PubMed

    Tian, Lipeng; Deshmukh, Abhijeet; Prasad, Neha; Jang, Yoon-Young

    2016-01-01

    Alcohol consumption has long been a global problem affecting human health, and has been found to influence both fetal and adult liver functions. However, how alcohol affects human liver development and liver progenitor cells remains largely unknown. Here, we used human induced pluripotent stem cells (iPSCs) as a model to examine the effects of alcohol, on multi-stage hepatic cells including hepatic progenitors, early and mature hepatocyte-like cells derived from human iPSCs. While alcohol has little effect on endoderm development from iPSCs, it reduces formation of hepatic progenitor cells during early hepatic specification. The proliferative activities of early and mature hepatocyte-like cells are significantly decreased after alcohol exposure. Importantly, at a mature stage of hepatocyte-like cells, alcohol treatment increases two liver progenitor subsets, causes oxidative mitochondrial injury and results in liver disease phenotypes (i.e., steatosis and hepatocellular carcinoma associated markers) in a dose dependent manner. Some of the phenotypes were significantly improved by antioxidant treatment. This report suggests that fetal alcohol exposure may impair generation of hepatic progenitors at early stage of hepatic specification and decrease proliferation of fetal hepatocytes; meanwhile alcohol injury in post-natal or mature stage human liver may contribute to disease phenotypes. This human iPSC model of alcohol-induced liver injury can be highly valuable for investigating alcoholic injury in the fetus as well as understanding the pathogenesis and ultimately developing effective treatment for alcoholic liver disease in adults. PMID:27570479

  16. Alcohol Increases Liver Progenitor Populations and Induces Disease Phenotypes in Human IPSC-Derived Mature Stage Hepatic Cells

    PubMed Central

    Tian, Lipeng; Deshmukh, Abhijeet; Prasad, Neha; Jang, Yoon-Young

    2016-01-01

    Alcohol consumption has long been a global problem affecting human health, and has been found to influence both fetal and adult liver functions. However, how alcohol affects human liver development and liver progenitor cells remains largely unknown. Here, we used human induced pluripotent stem cells (iPSCs) as a model to examine the effects of alcohol, on multi-stage hepatic cells including hepatic progenitors, early and mature hepatocyte-like cells derived from human iPSCs. While alcohol has little effect on endoderm development from iPSCs, it reduces formation of hepatic progenitor cells during early hepatic specification. The proliferative activities of early and mature hepatocyte-like cells are significantly decreased after alcohol exposure. Importantly, at a mature stage of hepatocyte-like cells, alcohol treatment increases two liver progenitor subsets, causes oxidative mitochondrial injury and results in liver disease phenotypes (i.e., steatosis and hepatocellular carcinoma associated markers) in a dose dependent manner. Some of the phenotypes were significantly improved by antioxidant treatment. This report suggests that fetal alcohol exposure may impair generation of hepatic progenitors at early stage of hepatic specification and decrease proliferation of fetal hepatocytes; meanwhile alcohol injury in post-natal or mature stage human liver may contribute to disease phenotypes. This human iPSC model of alcohol-induced liver injury can be highly valuable for investigating alcoholic injury in the fetus as well as understanding the pathogenesis and ultimately developing effective treatment for alcoholic liver disease in adults. PMID:27570479

  17. Hepatic progenitor cells of biliary origin with liver repopulation capacity

    PubMed Central

    Boulter, Luke; Tsuchiya, Atsunori; Cole, Alicia M; Hay, Trevor; Guest, Rachel V; Wojtacha, Davina; Man, Tak Yung; Mackinnon, Alison; Ridgway, Rachel A; Kendall, Timothy; Williams, Michael J; Jamieson, Thomas; Raven, Alex; Hay, David C; Iredale, John P; Clarke, Alan R; Sansom, Owen J; Forbes, Stuart J

    2015-01-01

    Summary Hepatocytes and cholangiocytes self renew following liver injury. Following severe injury hepatocytes are increasingly senescent, whether Hepatic Progenitor Cells (HPCs) then contribute to liver regeneration is unclear. Here, we describe a mouse model where Mdm2 is inducibly deleted in over 98% of hepatocytes, causing apoptosis, necrosis and senescence with nearly all hepatocytes expressing p21. This results in florid HPC activation, which is necessary for survival, followed by complete, functional liver reconstitution. HPCs isolated from genetically normal mice, using cell surface markers, were highly expandable and phenotypically stable in vitro. These HPCs were transplanted into adult mouse livers where hepatocyte Mdm2 was repeatedly deleted, creating a non-competitive repopulation assay. Transplanted HPCs contributed significantly to restoration of liver parenchyma, regenerating hepatocytes and biliary epithelia, highlighting their in vivo lineage potency. HPCs are therefore a potential future alternative to hepatocyte or liver transplantation for liver disease. PMID:26192438

  18. Hepatic progenitor cells of biliary origin with liver repopulation capacity.

    PubMed

    Lu, Wei-Yu; Bird, Thomas G; Boulter, Luke; Tsuchiya, Atsunori; Cole, Alicia M; Hay, Trevor; Guest, Rachel V; Wojtacha, Davina; Man, Tak Yung; Mackinnon, Alison; Ridgway, Rachel A; Kendall, Timothy; Williams, Michael J; Jamieson, Thomas; Raven, Alex; Hay, David C; Iredale, John P; Clarke, Alan R; Sansom, Owen J; Forbes, Stuart J

    2015-08-01

    Hepatocytes and cholangiocytes self-renew following liver injury. Following severe injury hepatocytes are increasingly senescent, but whether hepatic progenitor cells (HPCs) then contribute to liver regeneration is unclear. Here, we describe a mouse model where the E3 ubiquitin ligase Mdm2 is inducibly deleted in more than 98% of hepatocytes, causing apoptosis, necrosis and senescence with nearly all hepatocytes expressing p21. This results in florid HPC activation, which is necessary for survival, followed by complete, functional liver reconstitution. HPCs isolated from genetically normal mice, using cell surface markers, were highly expandable and phenotypically stable in vitro. These HPCs were transplanted into adult mouse livers where hepatocyte Mdm2 was repeatedly deleted, creating a non-competitive repopulation assay. Transplanted HPCs contributed significantly to restoration of liver parenchyma, regenerating hepatocytes and biliary epithelia, highlighting their in vivo lineage potency. HPCs are therefore a potential future alternative to hepatocyte or liver transplantation for liver disease.

  19. Liver-Regenerative Transplantation: Regrow and Reset

    PubMed Central

    de l’Hortet, A. Collin; Takeishi, K.; Guzman-Lepe, J.; Handa, K.; Matsubara, K.; Fukumitsu, K.; Dorko, K.; Presnell, S. C.; Yagi, H.; Soto-Gutierrez, A.

    2016-01-01

    Liver transplantation, either a partial liver from a living or deceased donor or a whole liver from a deceased donor, is the only curative therapy for severe end-stage liver disease. Only one-third of those on the liver transplant waiting list will be transplanted, and the demand for livers is projected to increase 23% in the next 20 years. Consequently, organ availability is an absolute constraint on the number of liver transplants that can be performed. Regenerative therapies aim to enhance liver tissue repair and regeneration by any means available (cell repopulation, tissue engineering, biomaterials, proteins, small molecules, and genes). Recent experimental work suggests that liver repopulation and engineered liver tissue are best suited to the task if an unlimited availability of functional induced pluripotent stem (iPS)–derived liver cells can be achieved. The derivation of iPS cells by reprogramming cell fate has opened up new lines of investigation, for instance, the generation of iPS-derived xenogeneic organs or the possibility of simply inducing the liver to reprogram its own hepatocyte function after injury. We reviewed current knowledge about liver repopulation, generation of engineered livers and reprogramming of liver function. We also discussed the numerous barriers that have to be overcome for clinical implementation. PMID:26699680

  20. Increased All-Cause, Liver, and Cardiac Mortality among Hepatitis C Virus-seropositive Blood Donors

    PubMed Central

    Guiltinan, Anne M.; Kaidarova, Zhanna; Custer, Brian; Orland, Jennie; Strollo, Angela; Cyrus, Sherri; Busch, Michael P.; Murphy, Edward L.

    2010-01-01

    Hospital-based studies suggest that hepatitis C virus (HCV) infection causes frequent cirrhosis, hepatocellular carcinoma, and mortality, but epidemiologic studies have shown less morbidity and mortality. The authors performed a retrospective cohort study of 10,259 recombinant immunoblot assay-confirmed, HCV antibody-positive (HCV+), allogeneic blood donors from 1991 to 2002 and 10,259 HCV antibody-negative (HCV−) donors matched for year of donation, age, gender, and Zone Improvement Plan Code (ZIP Code). Vital status through 2003 was obtained from the US National Death Index, and hazard ratios with 95% confidence intervals were calculated by survival analysis. After a mean follow-up of 7.7 years, there were 601 (2.92%) deaths: 453 HCV+ and 148 HCV− (hazard ratio (HR) = 3.13, 95% confidence interval (CI): 2.60, 3.76). Excess mortality in the HCV+ group was greatest in liver-related (HR = 45.99, 95% CI: 11.32, 186.74), drug- or alcohol-related (HR = 10.81, 95% CI: 4.68, 24.96), and trauma/suicide (HR = 2.99, 95% CI: 2.05, 4.36) causes. There was also an unexpected increase in cardiovascular mortality among the HCV+ donors (HR = 2.21, 95% CI: 1.41, 3.46). HCV infection is associated with a significant, threefold increase in overall mortality among former blood donors, including significantly increased mortality from liver and cardiovascular causes. High rates of mortality from drug/alcohol and trauma/suicide causes are likely due to lifestyle factors and may be at least partially preventable. PMID:18203734

  1. Impaired Gallbladder Motility and Increased Gallbladder Wall Thickness in Patients with Nonalcoholic Fatty Liver Disease

    PubMed Central

    Colak, Yasar; Bozbey, Gulcin; Erim, Tolga; Caklili, Ozge Telci; Ulasoglu, Celal; Senates, Ebubekir; Mutlu, Hasan Huseyin; Mesci, Banu; Doğan, Mehmet Sait; Tasan, Guralp; Enc, Feruze Yilmaz; Tuncer, Ilyas

    2016-01-01

    Background/Aims Nonalcoholic fatty liver disease (NAFLD) is currently the most common chronic liver disease worldwide. Along with the increase in the incidence of NAFLD and associated obesity, an increase in gallbladder disease (GD) has been noted. This has led to the identification of a new disease entity called fatty GD. There is a gap in the literature on the dynamics of gallbladder function in patients with NAFLD. Methods An observational case-control study, a total of 50 patients with biopsy proven NAFLD without gallbladder stone/sludge and 38 healthy comparison subjects were enrolled. Fasting, postprandial gallbladder volumes (PGV), gallbladder ejection fraction (GEF), and fasting gallbladder wall thickness (FGWT) were measured by real-time 2-dimensional ultrasonography. Results Fasting gallbladder wall thickness, fasting gallbladder volumes and PGV were significantly higher in patients with NAFLD than control subjects (P < 0.001, P = 0.006, and P < 0.001, respectively). Gallbladder ejection fraction was significantly lower in the NAFLD group than the controls (P = 0.008). The presence of NAFLD was an independent predictor for GEF, PGV, and FGWT. Also, steatosis grade was an independent predictor for GEF, and GEF was significantly lower in the nonalcoholic steatohepatitis (NASH) subgroup than the controls. Conclusions Gallbladder dysfunction and increase in gallbladder wall thickness exists in asymptomatic (without stone/sludge and related symptoms) patients with NAFLD and are useful in identifying fatty GD. Measurement of these variables in NAFLD patients may be useful in identifying those at higher risk for GD. PMID:26932908

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

    SciTech Connect

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

    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.

  3. Biochemical evaluation of virtual screening methods reveals a cell-active inhibitor of the cancer-promoting phosphatases of regenerating liver.

    PubMed

    Hoeger, Birgit; Diether, Maren; Ballester, Pedro J; Köhn, Maja

    2014-12-17

    Computationally supported development of small molecule inhibitors has successfully been applied to protein tyrosine phosphatases in the past, revealing a number of cell-active compounds. Similar approaches have also been used to screen for small molecule inhibitors for the cancer-related phosphatases of regenerating liver (PRL) family. Still, selective and cell-active compounds are of limited availability. Since especially PRL-3 remains an attractive drug target due to its clear role in cancer metastasis, such compounds are highly demanded. In this study, we investigated various virtual screening approaches for their applicability to identify novel small molecule entities for PRL-3 as target. Biochemical evaluation of purchasable compounds revealed ligand-based approaches as well suited for this target, compared to docking-based techniques that did not perform well in this context. The best hit of this study, a 2-cyano-2-ene-ester and hence a novel chemotype targeting the PRLs, was further optimized by a structure-activity-relationship (SAR) study, leading to a low micromolar PRL inhibitor with acceptable selectivity over other protein tyrosine phosphatases. The compound is active in cells, as shown by its ability to specifically revert PRL-3 induced cell migration, and exhibits similar effects on PRL-1 and PRL-2. It is furthermore suitable for fluorescence microscopy applications, and it is commercially available. These features make it the only purchasable, cell-active and acceptably selective PRL inhibitor to date that can be used in various cellular applications.

  4. Split liver transplant recipients do not have an increased frequency of acute kidney injury.

    PubMed

    Leithead, Joanna A; Armstrong, Matthew J; Corbett, Christopher; Andrew, Mark; Kothari, Chirag; Gunson, Bridget K; Mirza, Darius; Muiesan, Paolo; Ferguson, James W

    2014-11-01

    Small series have suggested that split liver transplantation (SLT) has an increased frequency of peri-operative acute kidney injury (AKI). However, the optimal donor selection in this setting could have a favourable impact on renal outcomes. This was a retrospective single-centre study of 76 adults who underwent SLT (right extended lobe) and 301 adults who underwent elective full-size donation after brain death liver transplantation (FSLT). SLT recipients were less likely than unmatched FSLT recipients to develop AKI (≥stage 1 KDIGO criteria) (40.3% vs. 56.1%, P = 0.016) and had a reduced frequency of renal replacement therapy (11.8% vs. 21.9%, P = 0.049). In 72 pairs of SLT patients and propensity risk score-matched FSLT controls the incidence of AKI was not significantly different (40.3% vs. 47.2%, P = 0.473). However, SLT patients were less likely to require renal replacement therapy (11.1% vs. 23.6%, P = 0.078; adjusted OR 0.32; 95% CI 0.11-0.87, P = 0.026). There was no association between SLT and the development of chronic kidney disease (eGFR<60 ml/min/1.73 m(2) , log rank P = 0.534). In conclusion, SLT is not associated with an increased frequency of AKI. These observations support the postulation that the optimal donor status of SLT may result in less graft injury with renal sparing effects. PMID:24964222

  5. The effect of silymarin on hepatic regeneration after partial hepatectomy: is silymarin effective in hepatic regeneration?

    PubMed Central

    Cetinkunar, Suleyman; Tokgoz, Serhat; Bilgin, Bulent Caglar; Erdem, Hasan; Aktimur, Recep; Can, Serpil; Erol, Huseyin Serkan; Isgoren, Atilla; Sozen, Selim; Polat, Yilmaz

    2015-01-01

    Aim: Silymarin from Silybum marianum was found to reduce liver injury. The aim of the present study was to investigate the effects of silymarin on hepatic regeneration in partially hepatectomized rats. Methods: Thirty Wistar-Albino rats were divided into 3 groups of 10 animals as sham, control and experimental groups. In the sham group (n=10) abdominal incision was closed after laparotomy. In the control group (n=10), the rats underwent 70% hepatectomy after laparotomy. In the experimental group (n=10) after partial 70% hepatectomy, silymarin (200 mg/kg/d) were given to rats for 10 days. Rats in three groups were sacrificed on 10 days. Aspartate (AST) and alanine transaminase (ALT), gamma glutamyl transferase (GGT), ALP, LDH and total bilirubin levels were measured using intracardiac blood samples. Tissue malondialdehyde (MDA) and tissue glutathion (GSH) and Superoxide dismutase (SOD) levels were measured. To reveal the increase in the mass of the remnant liver tissue in the control and experimental groups relative weight of the liver was calculated. Histopathological analysis of the liver was performed using a semi-quantitative scoring system. Results: A statistically significant difference among three groups was not shown for AST and ALT levels. A statistically significant difference was found between the groups as for total bilirubin and gamma glutamyl transferase levels. Increases in relative liver weights were seen with time in Groups 2 and 3. A statistically significant difference was not found for tissue malondialdehyde, Glutathion and Superoxide dismutase levels between hepatectomy and hepatectomy + silymarin groups. On liver tissue sections of the rats in the hepatectomy + silymarin group, increased regeneration and lipid peroxidation were observed accompanied by decreased antioxidant response. Conclusion: It has been observed that silymarin with many established functions such as antiproliferative, anti-inflammatory and energy antioxidant effects, does

  6. Method of treating intermetallic alloy hydrogenation/oxidation catalysts for improved impurity poisoning resistance, regeneration and increased activity

    DOEpatents

    Wright, Randy B.

    1992-01-01

    Alternate, successive high temperature oxidation and reduction treatments, in either order, of intermetallic alloy hydrogenation and intermetallic alloy oxidation catalysts unexpectedly improves the impurity poisoning resistance, regeneration capacity and/or activity of the catalysts. The particular alloy, and the final high temperature treatment given alloy (oxidation or reduction) will be chosen to correspond to the function of the catalyst (oxidation or hydrogenation).

  7. Current status of auxiliary partial orthotopic liver transplantation for acute liver failure.

    PubMed

    Rela, Mohamed; Kaliamoorthy, Ilankumaran; Reddy, Mettu Srinivas

    2016-09-01

    Auxiliary partial orthotopic liver transplantation (APOLT) is a technique of liver transplantation (LT) where a partial liver graft is implanted in an orthotopic position after leaving behind a part of the native liver. APOLT was previously considered technically challenging with results inferior to orthotopic liver transplantation. Results of this procedure have continued to improve with improving surgical techniques and a better understanding of the natural history of acute liver failure (ALF) and liver regeneration. The procedure is being increasingly accepted as a valid treatment option for ALF-especially in children. This article reviews the historical background to this operation, advances in the technique, and its current place in the management of ALF. Liver Transplantation 22 1265-1274 2016 AASLD. PMID:27357489

  8. Lactulose Increases Equol Production and Improves Liver Antioxidant Status in Barrows Treated with Daidzein

    PubMed Central

    Zheng, Weijiang; Hou, Yanjun; Yao, Wen

    2014-01-01

    Equol, one of the intestinal microflora metabolites of daidzein, has gained much attention for having greater bioactivity than its precursor (daidzein and daidzin) and seeming to be promoted by hydrogen gas. The effects of lactulose on the equol-producing capacity and liver antioxidant status of barrows treated with daidzein were investigated in this study. Male castrated piglets (barrows) of Landrace×Duroc, aged 40 days, were randomly divided into the following three groups: control group (C, n = 12, fed an isoflavones-free basic diet), daidzein group (D, n = 12, fed an isoflavones-free basic diet with 50 mg/kg of daidzein supplementation) and daidzein+lactulose group (D+L, n = 12, fed an isoflavones-free basic diet with 1% of lactulose and 50 mg/kg of daidzein supplementation). After 20 days, the profile of short-chain fatty acids in the colon digesta showed that lactulose significantly increased the fermented capacity in the gastrointestinal tract of the barrows. First-void urinary equol concentrations were significantly higher in the D+L group than in the D group (3.13±0.93 compared to 2.11±0.82 μg/ml, respectively). Furthermore, fecal equol levels were also significantly higher in the D+L group than in the D group (12.00±2.68 compared to 10.00±2.26 μg/g, respectively). The population of bacteroidetes and the percentage of bacteroidetes to bacteria in feces were higher in the D+L group than in the D group. The DGGE profiles results indicate that lactulose might shift the pathways of hydrogen utilization, and changing the profiles of SRB in feces. Moreover, the D+L group had weak enhancement of T-SOD and CuZn-SOD activities in the livers of barrows treated with daidzein. PMID:24667812

  9. Gallbladder sludge on ultrasound is predictive of increased liver enzymes and total bilirubin in cats.

    PubMed

    Harran, Nathaniel; d'Anjou, Marc-André; Dunn, Marilyn; Beauchamp, Guy

    2011-09-01

    The purposes of this retrospective study were to assess the prevalence of gallbladder sludge (GBS) in a population of cats presented for abdominal ultrasound in a teaching hospital and to determine its association with increased serum alanine aminotransferase (ALT), alkaline phosphatase (ALP), and total bilirubin (TB). Gallbladder sludge was detected in 152 (14%) of the cats undergoing abdominal ultrasound between 2004 and 2008. This population was compared to a control group of 32 cats without GBS. Alanine aminotransferase, ALP, and TB mean values were significantly higher in cats with GBS than in controls (P ≤ 0.0005) and odds for increased values in cats with GBS were 4.2 [95% confidence interval (CI): 1.6 to 11.0], 9.5 (95% CI: 2.2 to 41.7), and 4.1 (95% CI: 1.5 to 11.5), respectively (P ≤ 0.007). In conclusion, GBS is an uncommon ultrasonographic finding in cats that is predictive of increased liver enzymes and TB. More studies are needed to establish potential links between GBS and hepatobiliary disease in cats.

  10. Nitric oxide (NO) inhibits antigen-stimulated increases in vasoconstriction and glycogenolysis in perfused livers derived from sensitized rats

    SciTech Connect

    Hines, K.L.; Bates, J.N.; Fisher, R.A. )

    1991-03-11

    Recent studies in the authors laboratory demonstrated that infusion of antigen into perfused livers from sensitized rats produces increases in hepatic portal pressure, increases in hepatic glucose output and decreases in hepatic oxygen consumption. In the present study, effects of NO on these hepatic responses to antigen challenge were investigated. Infusion of NO into perfused livers from sensitized rats attenuated ovalbumin induced increases in hepatic portal pressure and glucose output approximately 85% and 90%, respectively, and abolished ovalbumin-induced decreases in hepatic oxygen consumption. The duration of ovalbumin-stimulated increases in hepatic portal pressure was reduced nearly 90% by NO. Similarly, infusion of NO into perfused livers from sensitized rats inhibited increases in hepatic portal pressure and glucose output in response to platelet-activating factor (PAF) nearly 80 and 90%, respectively. In contrast, NO inhibited completely hepatic vasoconstriction in response to phenylephrine without altering glycogenolytic responses to this {alpha}-adrenergic agonist. These results provide evidence for regulatory effects of NO on hemodynamic and glycogenolytic responses to antigen in perfused livers from sensitized rats. These observations support previous findings which suggest that hepatic responses to sensitizing antigen may be mediated by PAF or other autacoid mediators which stimulate glycogenolysis in liver by indirect mechanisms involving hepatic vasoconstriction.

  11. Arsenic exposure through drinking water increases the risk of liver and cardiovascular diseases in the population of West Bengal, India

    PubMed Central

    2012-01-01

    Background Arsenic is a natural drinking water contaminant affecting 26 million people in West Bengal, India. Chronic arsenic exposure causes cancer, cardiovascular disease, liver disease, neuropathies and ocular diseases. The aims of the present study were to assess bioindicators of hepatocellular injury as indicated by the levels of liver enzymes, to determine the auto immune status, as indicated by the amounts of anti-nuclear antibodies (ANA) and anti-dsDNA antibodies in their serum, and to predict cardiovascular risk in the arsenic exposed population. Methods Effect of chronic arsenic exposure on liver was determined by liver function tests. Autoimmune status was measured by measuring ANA and anti-dsDNA in serum. Inflammatory cytokines associated with increased cardiovascular disease risk, IL6, IL8 and MCP-1 were determined. Results Our results indicated that serum levels of bilirubin, alanine transaminase, aspartate transaminase, alkaline phosphatase and ANA were increased in the arsenic exposed population. Serum levels of IL6 and IL8 also increased in the arsenic exposed group. Conclusions Chronic arsenic exposure causes liver injury, increases the serum levels of autoimmune markers and imparts increased cardiovascular risk. PMID:22883023

  12. Cavernous Transformation of the Portal Vein Might Increase the Risk of Liver Abscess

    PubMed Central

    Ai, Xin-Bo; Gong, Fei-Yue; Wang, An; Liang, Hua-Min; Pan, Wen-Sheng

    2010-01-01

    Cavernous transformation of the portal vein (CTPV) is not quite common in adults, and cases with CTPV and acute liver abscess are lacking. We report a patient with CTPV inducing extrahepatic and intrahepatic obstruction, finally leading to acute liver abscess due to bile duct infection. We aim to find out the possible relationship between CTPV and acute liver abscess. A 45-year-old female patient was admitted to our hospital for recurrent upper abdominal pain and distension for one year, aggravated with fever for three years. A diagnosis of CTPV and liver abscess was made by 16-slice computed tomography. Effective antibiotics and drainage were used for this patients, and she was eventually cured. When treating patients with CTPV, extrahepatic and intrahepatic obstruction, one should be aware of the presence of acute liver abscess, and empirical antibiotics might be valuable. PMID:21060692

  13. Clinical Application of Bioartificial Liver Support Systems

    PubMed Central

    van de Kerkhove, Maarten Paul; Hoekstra, Ruurdtje; Chamuleau, Robert A. F. M.; van Gulik, Thomas M.

    2004-01-01

    Objective: To review the present status of bioartificial liver (BAL) devices and their obtained clinical results. Background: Acute liver failure (ALF) is a disease with a high mortality. Standard therapy at present is liver transplantation. Liver transplantation is hampered by the increasing shortage of organ donors, resulting in high incidence of patients with ALF dying on the transplantation waiting list. Among a variety of liver assist therapies, BAL therapy is marked as the most promising solution to bridge ALF patients to liver transplantation or to liver regeneration, because several BAL systems showed significant survival improvement in animal ALF studies. Until today, clinical application of 11 different BAL systems has been reported. Methods: A literature review was performed using MEDLINE and additional library searches. Only BAL systems that have been used in a clinical trial were included in this review. Results: Eleven BAL systems found clinical application. Three systems were studied in a controlled trial, showing no significant survival benefits, in part due to the insufficient number of patients included. The other systems were studied in a phase I trial or during treatment of a single patient and all showed to be safe. Most BAL therapies resulted in improvement of clinical and biochemical parameters. Conclusions: Bioartificial liver therapy for bridging patients with ALF to liver transplantation or liver regeneration is promising. Its clinical value awaits further improvement of BAL devices, replacement of hepatocytes of animal origin by human hepatocytes, and assessment in controlled clinical trials. PMID:15273544

  14. Method of treating intermetallic alloy hydrogenation/oxidation catalysts for improved impurity poisoning resistance, regeneration and increased activity

    DOEpatents

    Wright, R.B.

    1992-01-14

    Alternate, successive high temperature oxidation and reduction treatments, in either order, of intermetallic alloy hydrogenation and intermetallic alloy oxidation catalysts unexpectedly improves the impurity poisoning resistance, regeneration capacity and/or activity of the catalysts. The particular alloy, and the final high temperature treatment given alloy (oxidation or reduction) will be chosen to correspond to the function of the catalyst (oxidation or hydrogenation). 23 figs.

  15. Lovastatin increases arachidonic acid levels and stimulates thromboxane synthesis in human liver and monocytic cell lines.

    PubMed Central

    Hrboticky, N; Tang, L; Zimmer, B; Lux, I; Weber, P C

    1994-01-01

    The effect of lovastatin (LOV), the inhibitor of 3-hydroxy-3-methyl-glutaryl coenzyme A reductase, on linoleic acid (LA, 18:2n-6) metabolism was examined in human monocytic Mono Mac 6 (MM6) and hepatoma Hep G2 cells. The desaturation of LA was examined after LOV (72 h, 10 microM) or dimethylsulfoxide (LOV carrier, < 0.1%) and [14C]LA (last 18 h, 0.3 microCi, 5 microM). In both cell lines, LOV reduced the percentage of 14C label associated with LA and increased the percentage of label in the 20:4n-6 and the 22:5n-6 fractions. In Hep G2 but not MM6 cells, this effect was fully reversible by means of coincubation with mevalonic acid (500 microM), but not with cholesterol or lipoproteins. In both cell lines, the LOV-mediated increase in LA desaturation resulted in dose-dependent reductions of LA and elevations of AA in cellular phospholipids. The lipids secreted by LOV-treated Hep G2 cells were also enriched in arachidonic acid (AA). In the MM6 cells, LOV increased release of thromboxane upon stimulation with the calcium ionophore A23187. In summary, our findings of higher LA desaturation and AA enrichment of lipids secreted by the Hep G2 cells suggest that LOV treatment may increase the delivery of AA from the liver to extrahepatic tissues. The changes in membrane fatty acid composition can influence a variety of cellular functions, such as eicosanoid synthesis in monocytic cells. The mechanism appears to be related to the reduced availability of intermediates of cholesterogenesis. PMID:8282787

  16. Increased blood-brain transfer in a rabbit model of acute liver failure

    SciTech Connect

    Horowitz, M.E.; Schafer, D.F.; Molnar, P.; Jones, E.A.; Blasberg, R.G.; Patlak, C.S.; Waggoner, J.; Fenstermacher, J.D.

    1983-05-01

    The blood-to-brain transfer of (/sup 14/C)alpha-aminoisobutyric acid was investigated by quantitative autoradiography in normal rabbits and rabbits with acute liver failure induced by the selective hepatotoxin galactosamine. The blood-to-brain transfer of alpha-aminoisobutyric acid was similar in control animals and animals 2 and 7 h after galactosamine injections, but was increased five- to tenfold in certain gray-matter areas of the brain in animals 11 and 18 h after galactosamine treatment. No detectable differences in white-matter uptake of (/sup 14/C)alpha-aminoisobutyric acid were found between the control and treated groups. The increase in alpha-aminoisobutyric acid transfer within the gray-matter areas suggested that a general or nonspecific increase in brain capillary permeability occurred in these areas. No clinical signs of early hepatic encephalopathy were observed in the treated rabbits, except for 1 animal from the 18-h postgalactosamine group. Thus, enhanced blood-brain transfer of alpha-aminoisobutyric acid preceded the development of overt hepatic encephalopathy. The distribution of radioactivity after the intravenous administration of (/sup 14/C)galactosamine showed that virtually none of the hepatotoxin localized in the brain, suggesting that the drug itself does not have a direct effect upon the blood-brain barrier or the brain. The increased uptake of alpha-aminoisobutyric acid at 11 and 18 h implies that the transfer of other solutes would also be enhanced, that central nervous system homeostasis would be compromised, and that the resulting changes in brain fluid composition could contribute to or cause hepatic encephalopathy.

  17. Appendectomy correlates with increased risk of pyogenic liver abscess: A population-based cohort study in Taiwan.

    PubMed

    Liao, Kuan-Fu; Lai, Shih-Wei; Lin, Cheng-Li; Chien, Sou-Hsin

    2016-06-01

    Little is known on the association between appendectomy and pyogenic liver abscess. The objective of this study was to investigate the association between appendectomy and the risk of pyogenic liver abscess in Taiwan.This population-based retrospective cohort study was conducted using the hospitalization dataset of the Taiwan National Health Insurance Program. There were 212,530 subjects age 20 to 84 years with newly diagnosed appendectomy as the appendectomy group since 1998 to 2010, and 850,099 randomly selected subjects without appendectomy as the nonappendectomy group. Both appendectomy and nonappendectomy groups were matched with sex, age, comorbidities, and index year of diagnosing appendectomy. The incidence of pyogenic liver abscess at the end of 2011 was estimated in both groups. The multivariable Cox proportional hazards regression model was applied to investigate the hazard ratio (HR) and 95% confidence interval (CI) for risk of pyogenic liver abscess associated with appendectomy and other comorbidities including alcoholism, biliary stone, chronic kidney disease, chronic liver diseases, and diabetes mellitus.The overall incidence of pyogenic liver abscess was 1.73-fold greater in the appendectomy group than that in the nonappendectomy group (3.85 vs 2.22 per 10,000 person-years, 95% CI 1.71, 1.76). The multivariable regression analysis disclosed that the adjusted HR of pyogenic liver abscess was 1.77 for the appendectomy group (95% CI 1.59, 1.97), when compared with the nonappendectomy group.Appendectomy is associated with increased hazard of pyogenic liver abscess. Further studies remain necessary to confirm our findings. PMID:27368018

  18. Novel Comparative Pattern Count Analysis Reveals a Chronic Ethanol-Induced Dynamic Shift in Immediate Early NF-κB Genome-wide Promoter Binding During Liver Regeneration

    PubMed Central

    Kuttippurathu, Lakshmi; Patra, Biswanath; Hoek, Jan B; Vadigepalli, Rajanikanth

    2016-01-01

    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 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 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 1h post PHx. This set was associated with 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 1h binding targets showed ethanol-specific differential expression through 6h 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. PMID:26847025

  19. Pancreatic islet regeneration and some liver biochemical parameters of leaf extracts of Vitex doniana in normal and streptozotocin-induced diabetic albino rats

    PubMed Central

    Oche, Okpe; Sani, Ibrahim; Chilaka, Njoku Godwin; Samuel, Ndidi Uche; Samuel, Atabo

    2014-01-01

    Objective To test two water soluble extracts (aqueous and ethanolic) obtained from the leaves of Vitex doniana in normal and streptozotocin-induced diabetic rats for their effects on pancreatic endocrine tissues and serum marker enzymes for a period of 21 d. Methods A total of 55 rats divided into 11 groups of 5 rats each were assigned into diabetic and non-diabetic groups and followed by a daily administration of ethanolic and aqueous extracts for 21 d. Group 1 was the normal control while group 7 was treated with standard drug. Results The histopathological studies of the diabetic rats indicated increase in the volume density of islets, percent of β-cells and size of islet in the groups that received the plant extracts, which suggested regeneration of β-cells along with β-cells repairs, as compared with the non-treated diabetic control which showed complete degeneration of the islet cells. There was significant reduction (P<0.05) in the serum activities of marker enzymes, alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase in diabetes treated rats, whereas an insignificant increase (P>0.01) in the serum activities of marker enzymes was observed for non-diabetic treated rats. Results of total bilirubin, direct bilirubin and unconjugated bilirubin showed that diabetic control group was significantly higher (P<0.05) in total bilirubin and unconjugated bilirubin compared with treated groups while non-diabetic treated groups showed no significant increase (P>0.01) in total bilirubin and direct bilirubin compared with the normal control. Conclusion This herbal therapy appears to bring about repair/regeneration of the endocrine pancreas and hepatic cells protection in the diabetic rat. PMID:25182283

  20. Postnatal High-Fat Diet Increases Liver Steatosis and Apoptosis Threatened by Prenatal Dexamethasone through the Oxidative Effect.

    PubMed

    Huang, Ying-Hsien; Chen, Chih-Jen; Tang, Kuo-Shu; Sheen, Jiunn-Ming; Tiao, Mao-Meng; Tain, You-Lin; Chen, Chih-Cheng; Chu, En-Wei; Li, Shih-Wen; Yu, Hong-Ren; Huang, Li-Tung

    2016-01-01

    The objective of this study was to investigate cellular apoptosis in prenatal glucocorticoid overexposure and a postnatal high fat diet in rats. Pregnant Sprague-Dawley rats at gestational days 14 to 21 were administered saline (vehicle) or dexamethasone and weaned onto either a normal fat diet or a high fat diet for 180 days; in total four experimental groups were designated, i.e., vehicle treated group (VEH), dexamethasone treated group (DEX), vehicle treated plus high-fat diet (VHF), and dexamethasone treated plus high-fat diet (DHF). Chronic effects of prenatal liver programming were assessed at postnatal day 180. The apoptotic pathways involved proteins were analyzed by Western blotting for their expressions. Apoptosis and liver steatosis were also examined by histology. We found that liver steatosis and apoptosis were increased in the DHF, DEX, and VHF treated groups, and that the DHF treated group was increased at higher levels than the DEX and VHF treated groups. The expression of leptin was decreased more in the DHF treated group than in the DEX and VHF treated groups. Decreased peroxisome proliferator-activated receptor-gamma coactivator 1α, phosphoinositide-3-kinase, manganese superoxide dismutase and increased malondialdehyde expression levels were seen in DHF treated group relative to the DEX treated group. The DHF treated group exhibited higher levels of oxidative stress, apoptosis and liver steatosis than the DEX treated group. These results indicate that the environment of high-fat diet plays an important role in the development of liver injury after prenatal stress.

  1. Simvastatin increases liver branched-chain α-ketoacid dehydrogenase activity in rats fed with low protein diet.

    PubMed

    Knapik-Czajka, Malgorzata

    2014-11-01

    The rate-limiting step in branched-chain amino acids (BCAAs) disposal is catalyzed by the mitochondrial branched-chain α-ketoacid dehydrogenase complex (BCKDH). BCKDH activity is regulated mainly by a reversible dephosphorylation (activation)/phosphorylation (inactivation) cycle catalyzed by a specific phosphatase (BDP) and kinase (BDK). Current catalytic activity of BCKDH, described as BCKDH activity state, and thus also BCAAs catabolic rate depend directly on the portion of BCKDH occurring in its active dephosphorylated form. Liver BCKDH activity state alters in response to different nutritional factors. Feeding rats a low-protein diet decreases BCKDH activity. It has been previously shown that lipid lowering drugs, fibrates upregulate liver BCKDH activity and stimulate BCAAs catabolism, especially under the condition of dietary protein deprivation. Effect of statins on liver BCKDH activity has not been studied yet. The present study was aimed at investigating the in vivo effect of simvastatin on liver BCKDH activity, as well as E1, E2 and BDP and BDK mRNA levels in rats fed with either a standard (23% protein) or a low protein (8% protein) diet. For 14 days, simvastatin (80 mg/kg b wt/day) or the vehicle (0.3% methylcellulose) were administrated orally by gavage to the treated and control groups, respectively. The actual BCKDH and total BCKDH activities were assayed spectrophotometrically prior to and following incubation with lambda phosphatase, respectively. The mRNA levels of the selected genes were quantified by means of a semi-quantitative RT-PCR. In rats fed with the low protein diet simvastatin administration reversed physiological adaptation of liver BCKDH to protein restriction and increased liver BCKDH activity state by 39% (p<0.05). Changes in BCKDH activity did not correspond to any changes in mRNA levels for BCKDH catalytic and regulatory enzymes. On the contrary, in rats fed with standard diet liver BCKDH activity state did not alter substantially

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

    PubMed Central

    Sackey-Aboagye, Bridget; Olsen, Abby L.; Mukherjee, Sarmistha M.; Ventriglia, Alexander; Yokosaki, Yasuyuki; Greenbaum, Linda E.; Lee, Gi Yun; Naga, Hani

    2016-01-01

    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. PMID:27741254

  3. Effects of increased von Willebrand factor levels on primary hemostasis in thrombocytopenic patients with liver cirrhosis.

    PubMed

    Wannhoff, Andreas; Müller, Oliver J; Friedrich, Kilian; Rupp, Christian; Klöters-Plachky, Petra; Leopold, Yvonne; Brune, Maik; Senner, Mirja; Weiss, Karl-Heinz; Stremmel, Wolfgang; Schemmer, Peter; Katus, Hugo A; Gotthardt, Daniel N

    2014-01-01

    In patients with liver cirrhosis procoagulant and anticoagulant changes occur simultaneously. During primary hemostasis, platelets adhere to subendothelial structures, via von Willebrand factor (vWF). We aimed to investigate the influence of vWF on primary hemostasis in patients with liver cirrhosis. Therefore we assessed in-vitro bleeding time as marker of primary hemostasis in cirrhotic patients, measuring the Platelet Function Analyzer (PFA-100) closure times with collagen and epinephrine (Col-Epi, upper limit of normal ≤ 165 s) or collagen and ADP (Col-ADP, upper limit of normal ≤ 118 s). If Col-Epi and Col-ADP were prolonged, the PFA-100 was considered to be pathological. Effects of vWF on primary hemostasis in thrombocytopenic patients were analyzed and plasma vWF levels were modified by adding recombinant vWF or anti-vWF antibody. Of the 72 included cirrhotic patients, 32 (44.4%) showed a pathological result for the PFA-100. They had mean closure times (± SD) of 180 ± 62 s with Col-Epi and 160 ± 70 s with Col-ADP. Multivariate analysis revealed that hematocrit (P = 0.027) and vWF-antigen levels (P = 0.010) are the predictors of a pathological PFA-100 test in cirrhotic patients. In 21.4% of cirrhotic patients with platelet count ≥ 150/nL and hematocrit ≥ 27.0%, pathological PFA-100 results were found. In thrombocytopenic (< 150/nL) patients with cirrhosis, normal PFA-100 results were associated with higher vWF-antigen levels (462.3 ± 235.9% vs. 338.7 ± 151.6%, P = 0.021). These results were confirmed by multivariate analysis in these patients as well as by adding recombinant vWF or polyclonal anti-vWF antibody that significantly shortened or prolonged closure times, respectively. In conclusion, primary hemostasis is impaired in cirrhotic patients. The effect of reduced platelet count in cirrhotic patients can at least be partly compensated by increased vWF levels. Recombinant vWF could be an alternative to platelet transfusions in the future.

  4. Increased Contracaecum osculatum infection in Baltic cod (Gadus morhua) livers (1982-2012) associated with increasing grey seal (Halichoerus gryphus) populations.

    PubMed

    Haarder, Simon; Kania, Per W; Galatius, Anders; Buchmann, Kurt

    2014-07-01

    Grey seals (Halichoerus gryphus), the main final host of the gastric parasitic nematode Contracaecum osculatum in the Baltic, have recently recolonized the southwestern Baltic Sea. This colonization could lead to an increase in prevalence and intensity of third-stage larvae of C. osculatum in livers of Baltic cod (Gadus morhua), which serve as transport host for this helminth. We performed a parasitologic study of cod in spring 2012 and compared the results with previously unpublished data from 1982/1983. Additionally, grey seals were counted annually from 2000 to 2011 at three haul-out sites in the southwestern Baltic. Of 97 cod livers examined in the 1982/1983 survey, 22% harbored C. osculatum larvae, whereas 55.1% of the examined cod livers (n=185) were infected in 2012; the mean intensity and mean abundance increased from 4.3 and 0.9 to 20.2 and 11.1, respectively. Molecular identification (PCR) confirmed the identity of the larvae. The grey seal population increased markedly during the 12-yr period. We suggest that the elevated parasitism of cod livers is associated with the successful re-establishment of grey seals in the southwestern Baltic. PMID:24779467

  5. Increased Contracaecum osculatum infection in Baltic cod (Gadus morhua) livers (1982-2012) associated with increasing grey seal (Halichoerus gryphus) populations.

    PubMed

    Haarder, Simon; Kania, Per W; Galatius, Anders; Buchmann, Kurt

    2014-07-01

    Grey seals (Halichoerus gryphus), the main final host of the gastric parasitic nematode Contracaecum osculatum in the Baltic, have recently recolonized the southwestern Baltic Sea. This colonization could lead to an increase in prevalence and intensity of third-stage larvae of C. osculatum in livers of Baltic cod (Gadus morhua), which serve as transport host for this helminth. We performed a parasitologic study of cod in spring 2012 and compared the results with previously unpublished data from 1982/1983. Additionally, grey seals were counted annually from 2000 to 2011 at three haul-out sites in the southwestern Baltic. Of 97 cod livers examined in the 1982/1983 survey, 22% harbored C. osculatum larvae, whereas 55.1% of the examined cod livers (n=185) were infected in 2012; the mean intensity and mean abundance increased from 4.3 and 0.9 to 20.2 and 11.1, respectively. Molecular identification (PCR) confirmed the identity of the larvae. The grey seal population increased markedly during the 12-yr period. We suggest that the elevated parasitism of cod livers is associated with the successful re-establishment of grey seals in the southwestern Baltic.

  6. Is high AgNOR quantity in hepatocytes associated with increased risk of hepatocellular carcinoma in chronic liver disease?

    PubMed Central

    Derenzini, M; Trerè, D; Oliveri, F; David, E; Colombatto, P; Bonino, F; Brunetto, M R

    1993-01-01

    AIMS--To evaluate whether high numbers of silver staining nucleolar organiser regions (AgNORs) in hepatocytes are associated with increased risk of hepatocellular carcinoma in chronic liver disease. METHODS--The quantitative distribution of AgNORs was studied in the liver biopsy specimens of 33 patients with chronic liver disease, 11 of whom developed hepatocellular carcinoma. The interval between liver biopsy and diagnosis of hepatocellular carcinoma was 26 months (range one to 61 months); the mean follow up of patients without hepatocellular carcinoma was 45 months (range 24-59 months). Quantitative evaluation of AgNORs was carried out on silver stained routine sections by morphometric analysis, using a computer assisted image analysis system. RESULTS--High interphase AgNOR values (> 3 microns2) were found in hepatocytes of nine out of the 11 (82%) patients in whom neoplastic transformation occurred. Of the remaining 22 patients, only seven (31%) had AgNOR values higher than > 3 microns2 (chi 2 4.83; p = 0.036). CONCLUSIONS--These results indicate that high numbers of interphase AgNORs are associated with increased risk of hepatocellular carcinoma in patients with chronic liver disease. Images PMID:8408696

  7. Increased Soluble Leptin Receptor Levels in Morbidly Obese Patients With Insulin Resistance and Nonalcoholic Fatty Liver disease

    PubMed Central

    Medici, Valentina; Ali, Mohamed R.; Seo, Suk; Aoki, Christopher A.; Rossaro, Lorenzo; Kim, Kyoungmi; Fuller, Will D.; Vidovszky, Tamas J.; Smith, William; Jiang, Joy X.; Maganti, Kalyani; Havel, Peter J.; Kamboj, Amit; Ramsamooj, Rajendra; Török, Natalie J.

    2016-01-01

    The adipocyte hormone, leptin has been demonstrated to have profibrogenic actions in vitro and in animal models. However, no correlation was found between plasma leptin levels and fibrosis stage in humans. Thus, our aim was to study whether soluble leptin receptor (SLR) or free leptin index (FLI; calculated as the ratio of leptin to SLR), may correlate better with the features of metabolic syndrome and with the histological grade and stage of nonalcoholic fatty liver disease (NAFLD)/nonalcoholic steatohepatitis (NASH). We studied a population (n = 104) of morbidly obese patients undergoing bariatric surgery. Data including BMI, type 2 diabetes mellitus, hypertension, and hyperlipidemia were obtained. Plasma fasting leptin and SLR, fasting glucose and insulin were measured, and homeostasis model of assessment insulin resistance (HOMAIR) index and FLI were calculated. All patients had intraoperative liver biopsies. Leptin levels correlated with the BMI. The multiple regression analysis indicated that increasing HOMA and decreasing FLI were predictors of steatosis in the liver (P < 0.0003). SLR levels were positively correlated with the presence of diabetes mellitus and the stage of fibrosis. In conclusion, increased SLR levels in morbidly obese patients with diabetes are correlated with the stage of liver fibrosis, and may reflect progressive liver disease. PMID:20448542

  8. Increased soluble leptin receptor levels in morbidly obese patients with insulin resistance and nonalcoholic fatty liver disease.

    PubMed

    Medici, Valentina; Ali, Mohamed R; Seo, Suk; Aoki, Christopher A; Rossaro, Lorenzo; Kim, Kyoungmi; Fuller, Will D; Vidovszky, Tamas J; Smith, William; Jiang, Joy X; Maganti, Kalyani; Havel, Peter J; Kamboj, Amit; Ramsamooj, Rajendra; Török, Natalie J

    2010-12-01

    The adipocyte hormone, leptin has been demonstrated to have profibrogenic actions in vitro and in animal models. However, no correlation was found between plasma leptin levels and fibrosis stage in humans. Thus, our aim was to study whether soluble leptin receptor (SLR) or free leptin index (FLI; calculated as the ratio of leptin to SLR), may correlate better with the features of metabolic syndrome and with the histological grade and stage of nonalcoholic fatty liver disease (NAFLD)/nonalcoholic steatohepatitis (NASH). We studied a population (n = 104) of morbidly obese patients undergoing bariatric surgery. Data including BMI, type 2 diabetes mellitus, hypertension, and hyperlipidemia were obtained. Plasma fasting leptin and SLR, fasting glucose and insulin were measured, and homeostasis model of assessment insulin resistance (HOMA(IR)) index and FLI were calculated. All patients had intraoperative liver biopsies. Leptin levels correlated with the BMI. The multiple regression analysis indicated that increasing HOMA and decreasing FLI were predictors of steatosis in the liver (P < 0.0003). SLR levels were positively correlated with the presence of diabetes mellitus and the stage of fibrosis. In conclusion, increased SLR levels in morbidly obese patients with diabetes are correlated with the stage of liver fibrosis, and may reflect progressive liver disease. PMID:20448542

  9. The phosphatase of regenerating liver-3 (PRL-3) is important for IL-6-mediated survival of myeloma cells

    PubMed Central

    Slørdahl, Tobias S.; Abdollahi, Pegah; Vandsemb, Esten N.; Rampa, Christoph; Misund, Kristine; Baranowska, Katarzyna A.; Westhrin, Marita; Waage, Anders; Rø, Torstein B.; Børset, Magne

    2016-01-01

    Multiple myeloma (MM) is a neoplastic proliferation of bone marrow plasma cells. PRL-3 is a phosphatase induced by interleukin (IL)-6 and other growth factors in MM cells and promotes MM-cell migration. PRL-3 has also been identified as a marker gene for a subgroup of patients with MM. In this study we found that forced expression of PRL-3 in the MM cell line INA-6 led to increased survival of cells that were depleted of IL-6. It also caused redistribution of cells in cell cycle, with an increased number of cells in G2M-phase. Furthermore, forced PRL-3 expression significantly increased phosphorylation of Signal transducer and activator of transcription (STAT) 3 both in the presence and the absence of IL-6. Knockdown of PRL-3 with shRNA reduced survival in MM cell line INA-6. A pharmacological inhibitor of PRL-3 reduced survival in the MM cell lines INA-6, ANBL-6, IH-1, OH-2 and RPMI8226. The inhibitor also reduced survival in 9 of 9 consecutive samples of purified primary myeloma cells. Treatment with the inhibitor down-regulated the anti-apoptotic protein Mcl-1 and led to activation of the intrinsic apoptotic pathway. Inhibition of PRL-3 also reduced IL-6-induced phosphorylation of STAT3. In conclusion, our study shows that PRL-3 is an important mediator of growth factor signaling in MM cells and hence possibly a good target for treatment of MM. PMID:27036022

  10. Dietary selenomethionine increases exon-specific DNA methylation of the p53 gene in rat liver and colon mucosa.

    PubMed

    Zeng, Huawei; Yan, Lin; Cheng, Wen-Hsing; Uthus, Eric O

    2011-08-01

    The regulation of site-specific DNA methylation of tumor suppressor genes has been considered as a leading mechanism by which certain nutrients exert their anticancer property. This study was to investigate whether selenium (Se) affects the methylation of globe genomic DNA and the exon-specific p53 gene. Three groups of rats (n = 6-7/group) were fed the AIN-93G basal diet supplemented with 0 [Se deficient (D)], 0.15 [Se adequate (A)], or 4 mg [Se supranutritional (S)] (Se as l-selenomethionine)/kg diet for 104 d, respectively. Rats fed the A or S diet had greater plasma and liver glutathione peroxidase activity, liver thioredoxin reductase activity, and plasma homocysteine concentration than those fed the D diet. However, compared with the A diet, rats fed the S diet did not further increase these Se-dependent enzyme activities or homocysteine concentration. In contrast, Se concentrations in kidney, liver, gastrocnemius muscle, and plasma were increased in a Se-dose-dependent manner. Interestingly, rats fed the S diet had significantly less global liver genomic DNA methylation than those fed the D diet. However, the S diet significantly increased the methylation of the p53 gene (exons 5-8) but not the β-actin gene (exons 2-3) DNA in liver and colon mucosa compared with those fed the D diet. Taken together, long-term Se consumption not only affects selenoprotein enzyme activities, homocysteine, tissue Se concentrations, and global genomic DNA methylation but also increases exon-specific DNA methylation of the p53 gene in a Se-dose-dependent manner in rat liver and colon mucosa.

  11. GLUT2 proteins and PPARγ transcripts levels are increased in liver of ovariectomized rats: reversal effects of resistance training

    PubMed Central

    Tomaz, Luciane M.; Barbosa, Marina R.; Farahnak, Zahra; Lagoeiro, Cristiani G.; Magosso, Natalia S.S; Lavoie, Jean-Marc; Perez, Sérgio E. A.

    2016-01-01

    [Purpose] This study investigated the effects of ovariectomy (Ovx) and 12 weeks of resistance training (RT) on gene expression of GLUT2, the main glucose transporter in the liver, and on PPARγ, a transcription factor known to target GLUT2 expression. [Methods] Forty Holtzman rats were divided into 5 groups: Sham-sedentary (Sed), Sham- RT, Ovx-Sed, Ovx-RT, and Ovx-Sed with hormone replacement (E2). The RT protocol consisted of sessions held every 72 h for 12 weeks, during which the animals performed 4 to 9 vertical climbs (1.1 m) at 2 min intervals with progressively heavier weights (30 g after the fourth climb) tied to the tail. The E2 silastic capsule was inserted into the rats’ backs 48 hours before the first RT session. [Results] In addition to liver fat, GLUT2 protein levels and PPARγ transcripts were increased (P < 0.05) in Ovx compared to Sham-Sed animals, suggesting increased hepatic glucose uptake under estrogen deficient conditions. RT and E2 in Ovx rats decreased liver fat accumulation as well as GLUT2 and PPARγ gene expression to the level of Sham- Sed animals. [Conclusion] The results of this study suggest that liver GLUT2 as well as PPARγ expression in Ovx rats are accompanied by increased fat accumulation and glucose uptake, thus providing a substrate for increased de novo lipogenesis. RT appears to be an appropriate exercise model to circumvent these effects. PMID:27508154

  12. Desulfurization sorbent regeneration

    DOEpatents

    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.

  13. Increased MMP-7 expression in biliary epithelium and serum underpins native liver fibrosis after successful portoenterostomy in biliary atresia.

    PubMed

    Kerola, Anna; Lampela, Hanna; Lohi, Jouko; Heikkilä, Päivi; Mutanen, Annika; Hagström, Jaana; Tervahartiala, Taina; Sorsa, Timo; Haglund, Caj; Jalanko, Hannu; Pakarinen, Mikko P

    2016-07-01

    The molecular mechanisms underlying progressive liver fibrosis following surgical treatment of biliary atresia (BA) remain unclear. Our aim was to address hepatic gene and protein expression and serum levels of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) after successful portoenterostomy (PE), and relate them to histological signs of liver injury, clinical follow-up data and biochemical markers of hepatic function. LIver biopsies and serum samples were obtained from 25 children after successful PE at median age of 3.3 years. Serum MMP concentrations were determined by enzyme-linked immune sorbent assay. Hepatic gene expression of MMPs and TIMPs was analyzed using real-time reverse-transcription PCR. Liver expression of MMP-7 and cytokeratin-7 was studied using immunohistochemistry. Despite effective clearance of biochemical and histological cholestasis following PE, BA patients showed increased hepatic gene expression of MMP-7 (29-fold, p < 0.001), MMP-2 (3.1-fold, p < 0.001), MMP-14 (1.7-fold, p = 0.007), and TIMP-1 (1.8-fold, p < 0.001), when compared to controls. Similar to a biliary epithelial marker cytokeratin-7, expression of MMP-7 localized in biliary epithelium of bile ducts and ductal proliferations and periportal hepatocytes and was increased (p < 0.001) in relation to controls. BA patients had 6-fold higher serum levels of MMP-7 (p < 0.001), which correlated positively with hepatic MMP-7 gene (r = 0.548, p = 0.007) and protein (r = 0.532, p = 0.007) expression. Patients showed a positive correlation between biliary MMP-7 expression and Metavir fibrosis stage (r = 0.605, p = 0.001) and portal fibrosis grade (r = 0.606, p = 0.001). Neither similarly increased MMP-7 expression nor correlation with liver fibrosis was observed in patients with intestinal failure-associated liver disease and comparable Metavir stage. In conclusion, our findings support an unique role of altered

  14. Liver failure induces a systemic inflammatory response. Prevention by recombinant N-terminal bactericidal/permeability-increasing protein.

    PubMed

    Boermeester, M A; Houdijk, A P; Meyer, S; Cuesta, M A; Appelmelk, B J; Wesdorp, R I; Hack, C E; Van Leeuwen, P A

    1995-11-01

    The observed increased susceptibility of patients with fulminant hepatic failure for local and systemic infections has been hypothesized to be due to a failure for the hepatic clearance function and subsequent leaking of endogenous endotoxins into the systemic circulation. However, experimental evidence for such a systemic inflammation during liver failure due to endogenous endotoxemia is lacking. Therefore, we designed a study to clarify whether circulating endotoxins due to liver failure could lead to the development of systemic inflammations. In a rat model for liver failure induced by a two-thirds partial hepatectomy, we evaluated the course of circulating tumor necrosis factor and interleukin-6, changes in blood chemistry and hemodynamics, and histopathological changes in the lungs. Partially hepatectomized animals, but not sham-operated animals, demonstrated cardiac failure, increased levels of creatinin and urea, metabolic acidosis, high plasma levels of tumor necrosis factor and interleukin-6, and an influx of PMNs in the lungs-together indicating the development of a systemic inflammatory response. Continuous infusion of recombinant N-terminal bactericidal/permeability-increasing protein (rBPI23), a well described endotoxin-neutralizing protein, prevented these inflammatory reactions. Ex vivo experiments with rat plasma samples confirmed the presence of circulating endotoxins in partially hepatectomized rats as opposed to those treated with rBPI23. Thus, our results indicate that the early phase of liver failure induces a systemic inflammatory response triggered by circulating endotoxins, which can be prevented by perioperative infusion of rBPI23.

  15. Reproduction Does Not Adversely Affect Liver Mitochondrial Respiratory Function but Results in Lipid Peroxidation and Increased Antioxidants in House Mice

    PubMed Central

    Mowry, Annelise V.; Kavazis, Andreas N.; Sirman, Aubrey E.; Potts, Wayne K.; Hood, Wendy R.

    2016-01-01

    Reproduction is thought to come at a cost to longevity. Based on the assumption that increased energy expenditure during reproduction is associated with increased free-radical production by mitochondria, oxidative damage has been suggested to drive this trade-off. We examined the impact of reproduction on liver mitochondrial function by utilizing post-reproductive and non-reproductive house mice (Mus musculus) living under semi-natural conditions. The age-matched post-reproductive and non-reproductive groups were compared after the reproductive females returned to a non-reproductive state, so that both groups were in the same physiological state at the time the liver was collected. Despite increased oxidative damage (p = 0.05) and elevated CuZnSOD (p = 0.002) and catalase (p = 0.04) protein levels, reproduction had no negative impacts on the respiratory function of liver mitochondria. Specifically, in a post-reproductive, maintenance state the mitochondrial coupling (i.e., respiratory control ratio) of mouse livers show no negative impacts of reproduction. In fact, there was a trend (p = 0.059) to suggest increased maximal oxygen consumption by liver mitochondria during the ADP stimulated state (i.e., state 3) in post-reproduction. These findings suggest that oxidative damage may not impair mitochondrial respiratory function and question the role of mitochondria in the trade-off between reproduction and longevity. In addition, the findings highlight the importance of quantifying the respiratory function of mitochondria in addition to measuring oxidative damage. PMID:27537547

  16. INCREASED LIVER PATHOLOGY IN HEPATITIS C VIRUS TRANSGENIC MICE EXPRESSING THE HEPATITIS B VIRUS X PROTEIN

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Transgenic mice expressing the full-length HCV coding sequence were crossed with mice that express the HBV X gene-encoded regulatory protein HBx (ATX mice) to test the hypothesis that HBx expression accelerates HCV-induced liver pathogenesis. At 16 months (mo) of age, hepatocellular carcinoma was id...

  17. Mesenchymal Stem Cells Increase Neo-Angiogenesis and Albumin Production in a Liver Tissue-Engineered Engraftment

    PubMed Central

    Carraro, Amedeo; Buggio, Maurizio; Gardin, Chiara; Tedeschi, Umberto; Ferroni, Letizia; Zavan, Barbara

    2016-01-01

    The construction of a three-dimensional (3D) liver tissue is limited by many factors; one of them is the lack of vascularization inside the tissue-engineered construct. An engineered liver pocket-scaffold able to increase neo-angiogenesis in vivo could be a solution to overcome these limitations. In this work, a hyaluronan (HA)-based scaffold enriched with human mesenchymal stem cells (hMSCs) and rat hepatocytes was pre-conditioned in a bioreactor system, then implanted into the liver of rats. Angiogenesis and hepatocyte metabolic functions were monitored. The formation of a de novo vascular network within the HA-based scaffold, as well as an improvement in albumin production by the implanted hepatocytes, were detected. The presence of hMSCs in the HA-scaffold increased the concentration of growth factors promoting angiogenesis inside the graft. This event ensured a high blood vessel density, coupled with a support to metabolic functions of hepatocytes. All together, these results highlight the important role played by stem cells in liver tissue-engineered engraftment. PMID:26985891

  18. Postnatal High-Fat Diet Increases Liver Steatosis and Apoptosis Threatened by Prenatal Dexamethasone through the Oxidative Effect

    PubMed Central

    Huang, Ying-Hsien; Chen, Chih-Jen; Tang, Kuo-Shu; Sheen, Jiunn-Ming; Tiao, Mao-Meng; Tain, You-Lin; Chen, Chih-Cheng; Chu, En-Wei; Li, Shih-Wen; Yu, Hong-Ren; Huang, Li-Tung

    2016-01-01

    The objective of this study was to investigate cellular apoptosis in prenatal glucocorticoid overexposure and a postnatal high fat diet in rats. Pregnant Sprague-Dawley rats at gestational days 14 to 21 were administered saline (vehicle) or dexamethasone and weaned onto either a normal fat diet or a high fat diet for 180 days; in total four experimental groups were designated, i.e., vehicle treated group (VEH), dexamethasone treated group (DEX), vehicle treated plus high-fat diet (VHF), and dexamethasone treated plus high-fat diet (DHF). Chronic effects of prenatal liver programming were assessed at postnatal day 180. The apoptotic pathways involved proteins were analyzed by Western blotting for their expressions. Apoptosis and liver steatosis were also examined by histology. We found that liver steatosis and apoptosis were increased in the DHF, DEX, and VHF treated groups, and that the DHF treated group was increased at higher levels than the DEX and VHF treated groups. The expression of leptin was decreased more in the DHF treated group than in the DEX and VHF treated groups. Decreased peroxisome proliferator-activated receptor-gamma coactivator 1α, phosphoinositide-3-kinase, manganese superoxide dismutase and increased malondialdehyde expression levels were seen in DHF treated group relative to the DEX treated group. The DHF treated group exhibited higher levels of oxidative stress, apoptosis and liver steatosis than the DEX treated group. These results indicate that the environment of high-fat diet plays an important role in the development of liver injury after prenatal stress. PMID:26978357

  19. Tubulin-tyrosine Ligase (TTL)-mediated Increase in Tyrosinated α-Tubulin in Injured Axons Is Required for Retrograde Injury Signaling and Axon Regeneration.

    PubMed

    Song, Wenjun; Cho, Yongcheol; Watt, Dana; Cavalli, Valeria

    2015-06-01

    Injured peripheral neurons successfully activate a pro-regenerative program to enable axon regeneration and functional recovery. The microtubule-dependent retrograde transport of injury signals from the lesion site in the axon back to the cell soma stimulates the increased growth capacity of injured neurons. However, the mechanisms initiating this retrograde transport remain poorly understood. Here we show that tubulin-tyrosine ligase (TTL) is required to increase the levels of tyrosinated α-tubulin at the axon injury site and plays an important role in injury signaling. Preventing the injury-induced increase in tyrosinated α-tubulin by knocking down TTL impairs retrograde organelle transport and delays activation of the pro-regenerative transcription factor c-Jun. In the absence of TTL, axon regeneration is reduced severely. We propose a model in which TTL increases the levels of tyrosinated α-tubulin locally at the injury site to facilitate the retrograde transport of injury signals that are required to activate a pro-regenerative program.

  20. Urinary proteomic profiling reveals diclofenac-induced renal injury and hepatic regeneration in mice

    SciTech Connect

    Swelm, Rachel P.L. van; Laarakkers, Coby M.M.; Pertijs, Jeanne C.L.M.; Verweij, Vivienne; Masereeuw, Rosalinde; Russel, Frans G.M.

    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.

  1. Increase in liver nuclear tri-iodothyronine receptors associated with increased deoxyribonucleic acid by long-term administration of tri-iodothyronine in thyroidectomized rats

    PubMed Central

    Nakamura, Hirotoshi; Hamada, Satoshi; Imura, Hiroo

    1979-01-01

    The effect of long-term administration of small amounts of tri-iodothyronine was examined on the nuclear tri-iodothyronine receptors in rat liver. The maximal binding capacity (Cmax.) and association constant (Ka) of the receptors were determined in thyroidectomized rats given vehicle alone (group A), 2μg of tri-iodothyronine/100g body wt. (group B) or 7μg of tri-iodothyronine/100g body wt. (group C) for 2 weeks. Scatchard analyses with correction for the amount of endogenous tri-iodothyronine revealed that Cmax. values per g of liver were increased to 1.5 and 2.7 times the control value in groups B and C respectively. Since concentrations of DNA per g of liver were significantly increased in the two groups of hormone-treated rats, Cmax. values per mg of DNA were nearly the same in group B, but still increased significantly in group C compared with group A. Ka values remained unchanged in all three groups of animals. Mitochondrial α-glycerophosphate dehydrogenase activity was 9.6 and 28.7 times as high in groups B and C, respectively, as in group A. Concentrations of endogenous tri-iodothyronine bound to non-histone protein were substantially increased in groups B and C, although concentrations of serum tri-iodothyronine remained rather low. The results obtained indicate that the long-term administration of tri-iodothyronine in small doses induces an increase in the nuclear receptors associated with increased DNA with and without accompanying a relative increase in the receptor concentration in thyroidectomized rats. Also the hormonal effect is closely related to the total number of the nuclear receptors and the concentrations of nuclear tri-iodothyronine bound to the receptors rather than the serum tri-iodothyronine concentrations. PMID:230825

  2. Regeneration inducers in limb regeneration.

    PubMed

    Satoh, Akira; Mitogawa, Kazumasa; Makanae, Aki

    2015-08-01

    Limb regeneration ability, which can be observed in amphibians, has been investigated as a representative phenomenon of organ regeneration. Recently, an alternative experimental system called the accessory limb model was developed to investigate early regulation of amphibian limb regeneration. The accessory limb model contributed to identification of limb regeneration inducers in urodele amphibians. Furthermore, the accessory limb model may be applied to other species to explore universality of regeneration mechanisms. This review aims to connect the insights recently gained to emboss universality of regeneration mechanisms among species. The defined molecules (BMP7 (or2) + FGF2 + FGF8) can transform skin wound healing to organ (limb) regeneration responses. The same molecules can initiate regeneration responses in some species. PMID:26100345

  3. Rapid induction in regenerating liver of RL/IF-1 (an I kappa B that inhibits NF-kappa B, RelB-p50, and c-Rel-p50) and PHF, a novel kappa B site-binding complex.

    PubMed

    Tewari, M; Dobrzanski, P; Mohn, K L; Cressman, D E; Hsu, J C; Bravo, R; Taub, R

    1992-06-01

    The liver is one of the few adult tissues that has the capacity to regenerate following hepatectomy or toxic damage. In examining the early growth response during hepatic regeneration, we found that a highly induced immediate-early gene in regenerating liver encodes RL/IF-1 (regenerating liver inhibitory factor) and is the rat homolog of human MAD-3 and probably of chicken pp40. RL/IF-1 has I kappa B activity of broad specificity in that it inhibits the binding of p50-p65 NF-kappa B, c-Rel-p50, and RelB-p50, but not p50 homodimeric NF-kappa B, to kappa B sites. Like RL/IF-1, several members of the NF-kappa B and rel family of transcription factors are immediate-early genes in regenerating liver and mitogen-treated cells. We examined changes in kappa B site binding activity during liver regeneration and discovered a rapidly induced novel kappa B site-binding complex designated PHF [posthepatectomy factor(s)]. PHF is induced over 1,000-fold within minutes posthepatectomy in a protein synthesis-independent manner, with peak activity at 30 min, and is not induced by sham operation. PHF is distinct from p50-p65 NF-kappa B, which is present only in the inactive form in liver posthepatectomy. Although early PHF complexes do not interact strongly with anti-p50 antibodies, PHF complexes present later (3 to 5 h) posthepatectomy react strongly, suggesting that they contain a p50 NF-kappa B subunit. Unlike p50-p65 NF-kappa B, c-Rel-p50, and RelB-p50 complexes, PHF binding to kappa B sites is not inhibited by RL/IF-1. One role of RL/IF-1 in liver regeneration may be to inhibit p50-p65 NF-kappa B activity present in hepatic cells, allowing for the preferential binding of PHF to kappa B sites. Because PHF is induced immediately posthepatectomy in the absence of de novo protein synthesis, PHF could have a role in the regulation of liver-specific immediate-early genes in regenerating liver.

  4. Parathyroid Hormone-Related Peptide (1-36) Enhances Beta Cell Regeneration and Increases Beta Cell Mass in a Mouse Model of Partial Pancreatectomy

    PubMed Central

    Mozar, Anaïs; Lin, Hugo; Williams, Katoura; Chin, Connie; Li, Rosemary; Kondegowda, Nagesha Guthalu; Stewart, Andrew F.; Garcia-Ocaña, Adolfo; Vasavada, Rupangi Chhaya

    2016-01-01

    Aims/Hypothesis Finding ways to stimulate the regeneration of endogenous pancreatic beta cells is an important goal in the treatment of diabetes. Parathyroid hormone-related protein (PTHrP), the full-length (1–139) and amino-terminal (1–36) peptides, enhance beta cell function, proliferation, and survival. Therefore, we hypothesize that PTHrP(1–36) has the potential to regenerate endogenous beta cells. Methods The partial pancreatectomy (PPx) mouse model of beta cell injury was used to test this hypothesis. Male Balb/c mice underwent either sham-operation or PPx, and were subsequently injected with PTHrP(1–36) (160μg/kg) or vehicle (veh), for 7, 30, or 90 days. The four groups of mice, sham-veh, sham-PTHrP, PPx-veh, and PPx-PTHrP were assessed for PTHrP and receptor expression, and glucose and beta cell homeostasis. Results PTHrP-receptor, but not the ligand, was significantly up-regulated in islets from mice that underwent PPx compared to sham-operated mice. This suggests that exogenous PTHrP could further enhance beta cell regeneration after PPx. PTHrP did not significantly affect body weight, blood glucose, plasma insulin, or insulin sensitivity, in either sham or PPx mice. Glucose tolerance improved in the PPx-PTHrP versus PPx-veh mice only in the early stages of treatment. As hypothesized, there was a significant increase in beta cell proliferation in PPx-PTHrP mice at days 7 and 30; however, this was normalized by day 90, compared to PPx-veh mice. Enhanced beta cell proliferation translated to a marked increase in beta cell mass at day 90, in PPx-PTHrP versus PPx-veh mice. Conclusions PTHrP(1–36) significantly enhances beta cell regeneration through increased beta cell proliferation and beta cell mass after PPx. Future studies will determine the potential of PTHrP to enhance functional beta cell mass in the setting of diabetes. PMID:27391423

  5. Limb regeneration.

    PubMed

    Simon, András; Tanaka, Elly M

    2013-01-01

    Limb regeneration is observed in certain members of the animal phyla. Some animals keep this ability during their entire life while others lose it at some time during development. How do animals regenerate limbs? Is it possible to find unifying, conserved mechanisms of limb regeneration or have different species evolved distinct means of replacing a lost limb? How is limb regeneration similar or different to limb development? Studies on many organisms, including echinoderms, arthropods, and chordates have provided significant knowledge about limb regeneration. In this focus article, we concentrate on tetrapod limb regeneration as studied in three model amphibians: newts, axolotls, and frogs. We review recent progress on tissue interactions during limb regeneration, and place those findings into an evolutionary context. PMID:24009038

  6. Progression from Nonalcoholic Fatty Liver to Nonalcoholic Steatohepatitis Is Marked by a Higher Frequency of Th17 Cells in the Liver and an Increased Th17/Resting Regulatory T Cell Ratio in Peripheral Blood and in the Liver.

    PubMed

    Rau, Monika; Schilling, Anne-Kristin; Meertens, Jan; Hering, Ilona; Weiss, Johannes; Jurowich, Christian; Kudlich, Theodor; Hermanns, Heike M; Bantel, Heike; Beyersdorf, Niklas; Geier, Andreas

    2016-01-01

    Nonalcoholic fatty liver disease is increasing in prevalence. It can be subdivided into nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH). Five to twenty percent of cases progress from NAFL to NASH. Increased hepatic Th17 cells and IL-17 expression were observed in NASH mice and patients, respectively. We analyzed CD4(+) effector T cells and regulatory T cells (Tregs) from peripheral blood and livers of NAFL and NASH patients. A total of 51 NAFL patients, 30 NASH patients, 31 nonalcoholic fatty liver disease patients (without histology), and 43 healthy controls were included. FACS analysis was performed on PBMCs and intrahepatic lymphocytes. Compared with healthy controls, a lower frequency of resting Tregs (rTregs; CD4(+)CD45RA(+)CD25(++)) and higher frequencies of IFN-γ(+) and/or IL-4(+) cells were detected among CD4(+) T cells of peripheral blood in NASH, and to a lesser degree in NAFL. In hepatic tissue, NAFL to NASH progression was marked by an increase in IL-17(+) cells among intrahepatic CD4(+) T cells. To define immunological parameters in peripheral blood to distinguish NAFL from NASH, we calculated different ratios. Th17/rTreg and Th2/rTreg ratios were significantly increased in NASH versus NAFL. The relevance of our findings for NASH pathogenesis was highlighted by the normalization of all of the changes 1 y after bariatric surgery. In conclusion, our data indicate that NAFL patients show changes in their immune cell profile compared with healthy controls. NAFL to NASH progression is marked by an increased frequency of IL-17(+) cells among intrahepatic CD4(+) T cells and higher Th17/rTreg and Th2/rTreg ratios in peripheral blood.

  7. Liver and circulating NK1.1(+)CD3(-) cells are increased in infection with attenuated Salmonella typhimurium and are associated with reduced tumor in murine liver cancer.

    PubMed

    Feltis, B A; Miller, J S; Sahar, D A; Kim, A S; Saltzman, D A; Leonard, A S; Wells, C L; Sielaff, T D

    2002-09-01

    An attenuated (DeltacyA, Deltacrp) strain of Salmonella typhimurium (chi4550) containing a gene for human IL-2 (chi4550pIL2) reduces hepatic tumor burden when orally inoculated into mice with liver cancer; however, wild-type S. typhimurium is also associated with cancer regression. Therefore, experiments were designed to clarify the invasiveness and the anti-tumor properties of three strains of S. typhimurium. S. typhimurium chi4550pIL2, chi4550, or wild type (WT) was incubated with mature Caco-2 and HT-29 enterocytes, and S. typhimurium internalization was assessed. For infectivity experiments, mice were orally inoculated with saline or 10(9)S. typhimurium chi4550pIL2, chi4550, or WT; 48 h later mice were sacrificed for analysis of cecal bacteria and S. typhimurium translocation to mesenteric lymph nodes. For experiments involving tumor implantation, four groups were studied: saline control, tumor alone, chi4550pIL2+tumor, and chi4550+tumor. Mice were orally inoculated with saline or S. typhimurium and underwent laparotomy 24 h later with 5 x 10(4) MCA38 murine adenocarcinoma cells injected into the spleen. On day 14, liver tumors were counted and peripheral blood and hepatic lymphocyte populations were analyzed by FACScan. Attenuated S. typhimurium exhibited decreased internalization by cultured enterocytes and decreased infectivity after oral inoculation. Mice treated with chi4550pIL2 or chi4550 had fewer liver tumors and increased populations of hepatic and circulating NK1.1(+)CD3(-) lymphocytes compared to mice treated with saline (P < 0.01). These data suggest that attenuated S. typhimurium may have an application as an anti-tumor agent.

  8. [Improving the solubility of fraxinellone to increase its oral bioavailability and hepatoprotective action against acute liver injury in mice].

    PubMed

    Ran, Qi-Qiong; Ruan, Li-Ping; Zhu, Dan-Ni; Yu, Bo-Yang

    2007-06-01

    Fraxinellone, the major component of Cortex Dictamni, is naturally degraded limonids compound. Fraxinellone has significant anti-inflammatory activity in acute liver injury model. However, the low solubility and permeability of fraxinellone limited its potential application and even therapeutic effects. The aim of the paper is to increase oral bioavailability of fraxinellone, thus improving its hepatoprotection effect in vivo. We evaluated the effects of different pH values and different solubilizer (PEG 6000, PVP K30, HP-beta-CD, F68 and SDS) on the solubility of fraxinellone. The results showed that HP-beta-CD increased solubility of fraxinellone up to 155 times compared to that of water. More than 2. 1 mg mL1 fraxinellone can be resolved when adding 20% HP-beta-CD. Mouse acute liver injury model induced hy CCl4 was used to evaluate in vivo activity of fraxinellone with or without HP-beta-CD. The result shows that the hepatoprotective activity of fraxinellone in 20% HP-beta-CD solution has been significantly improved compared with that of fraxinellone solution without HP-beta-CD: the former inhibited 59 percent the increase of enzyme activity of ALT in liver, while the latter only inhibited 20 percent. A LC-MS/MS method was also developed to determine the oral bioavailability of fraxinellone. Fraxinellone solution with or without HP-betaCD were administered intra-gastrically to rats, and it was found that the bioavailahility of fraxinellone with HP-beta-CD was 23%, while only 5% without HP-beta-CD. The result showed that HP-beta-CD can significantly increase the solubility and permeability of fraxinellone, and improve bioavailability 3. 5 fold in vivo acute liver injury model as well as administration.

  9. Mesenchymal Stem Cells Within Gelatin/CaSO4 Scaffolds Treated Ex Vivo with Low Doses of BMP-2 and Wnt3a Increase Bone Regeneration.

    PubMed

    Aquino-Martínez, Rubén; Rodríguez-Carballo, Edgardo; Gámez, Beatriz; Artigas, Natalia; Carvalho-Lobato, Patricia; Manzanares-Céspedes, Maria Cristina; Rosa, Jose Luis; Ventura, Francesc

    2016-01-01

    The delivery of osteogenic factors is a proven therapeutic strategy to promote bone regeneration. Bone morphogenetic proteins (BMPs) constitute a family of cytokines with well-known osteogenic and bone regenerative abilities. However, clinical uses of BMPs require high doses that have been associated with complications such as osteolysis, ectopic bone formation, or hematoma formation. In the present work, we sought to improve bone tissue engineering through an approach that combines the use of bone marrow-derived mesenchymal stem cells (BMMSCs), composite scaffolds, and osteoinductive agents. We employed a composite gelatin/CaSO4 scaffold that allows for an early expansion of seeded BMMSCs, which is followed by an increased level of osteogenic differentiation after 10 days in culture. Furthermore, this scaffold enhanced bone formation by BMMSCs in a mouse model of critical-sized calvarial defect. More importantly, our results demonstrate that ex vivo pretreatment of BMMSCs with low amounts of BMP-2 (2 nM) and Wnt3a (50 ng/mL) for 24 h cooperatively increases the expression of osteogenic markers in vitro and bone regeneration in the critical-sized calvarial defect mouse model. These data provide a strong rationale for the development of an ex vivo cooperative use of BMP-2 and Wnt3a. Osteogenic factor cooperation might be applied to reduce the required amount of growth factors while obtaining higher therapeutic effects.

  10. High Dietary Iron and Radiation Exposure Increase Biomarkers of Oxidative Stress in Blood and Liver of Rats

    NASA Technical Reports Server (NTRS)

    Morgan, Jennifer L. L.; Theriot, Corey A.; Wu, Honglu; Smith, Scott M.; Zwart, Sara R.

    2012-01-01

    Radiation exposure and increased iron (Fe) status independently cause oxidative damage that can result in protein, lipid, and DNA oxidation. During space flight astronauts are exposed to both increased radiation and increased Fe stores. Increased body Fe results from a decrease in red blood cell mass and the typically high Fe content of the food system. In this study we investigated the combined effects of radiation exposure (0.375 Gy of Cs-137 every other day for 16 days for a total of 3 Gy) and high dietary Fe (650 mg Fe/kg diet compared to 45 mg Fe/kg for controls) in Sprague-Dawley rats (n=8/group). Liver and serum Fe were significantly increased in the high dietary Fe groups. Likewise, radiation treatment increased serum ferritin and Fe concentrations. These data indicate that total body Fe stores increase with both radiation exposure and excess dietary Fe. Hematocrit decreased in the group exposed to radiation, providing a possible mechanism for the shift in Fe indices after radiation exposure. Markers of oxidative stress were also affected by both radiation and high dietary Fe, evidenced by increased liver glutathione peroxidase (GPX) and serum catalase as well as decreased serum GPX. We thus found preliminary indications of synergistic effects of radiation exposure and increased dietary Fe, warranting further study. This study was funded by the NASA Human Research Project.

  11. Quantification of liver fat: A comprehensive review.

    PubMed

    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.

  12. Quantification of liver fat: A comprehensive review.

    PubMed

    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. PMID:26945465

  13. Increased Sensitivity to Binge Alcohol-Induced Gut Leakiness and Inflammatory Liver Disease in HIV Transgenic Rats.

    PubMed

    Banerjee, Atrayee; Abdelmegeed, Mohamed A; Jang, Sehwan; Song, Byoung-Joon

    2015-01-01

    The mechanisms of alcohol-mediated advanced liver injury in HIV-infected individuals are poorly understood. Thus, this study was aimed to investigate the effect of binge alcohol on the inflammatory liver disease in HIV transgenic rats as a model for simulating human conditions. Female wild-type (WT) or HIV transgenic rats were treated with three consecutive doses of binge ethanol (EtOH) (3.5 g/kg/dose oral gavages at 12-h intervals) or dextrose (Control). Blood and liver tissues were collected at 1 or 6-h following the last dose of ethanol or dextrose for the measurements of serum endotoxin and liver pathology, respectively. Compared to the WT, the HIV rats showed increased sensitivity to alcohol-mediated gut leakiness, hepatic steatosis and inflammation, as evidenced with the significantly elevated levels of serum endotoxin, hepatic triglycerides, histological fat accumulation and F4/80 staining. Real-time PCR analysis revealed that hepatic levels of toll-like receptor-4 (TLR4), leptin and the downstream target monocyte chemoattractant protein-1 (MCP-1) were significantly up-regulated in the HIV-EtOH rats, compared to all other groups. Subsequent experiments with primary cultured cells showed that both hepatocytes and hepatic Kupffer cells were the sources of the elevated MCP-1 in HIV-EtOH rats. Further, TLR4 and MCP-1 were found to be upregulated by leptin. Collectively, these results show that HIV rats, similar to HIV-infected people being treated with the highly active anti-retroviral therapy (HAART), are more susceptible to binge alcohol-induced gut leakiness and inflammatory liver disease than the corresponding WT, possibly due to additive or synergistic interaction between binge alcohol exposure and HIV infection. Based on these results, HIV transgenic rats can be used as a surrogate model to study the molecular mechanisms of many disease states caused by heavy alcohol intake in HIV-infected people on HAART.

  14. Increased Sensitivity to Binge Alcohol-Induced Gut Leakiness and Inflammatory Liver Disease in HIV Transgenic Rats.

    PubMed

    Banerjee, Atrayee; Abdelmegeed, Mohamed A; Jang, Sehwan; Song, Byoung-Joon

    2015-01-01

    The mechanisms of alcohol-mediated advanced liver injury in HIV-infected individuals are poorly understood. Thus, this study was aimed to investigate the effect of binge alcohol on the inflammatory liver disease in HIV transgenic rats as a model for simulating human conditions. Female wild-type (WT) or HIV transgenic rats were treated with three consecutive doses of binge ethanol (EtOH) (3.5 g/kg/dose oral gavages at 12-h intervals) or dextrose (Control). Blood and liver tissues were collected at 1 or 6-h following the last dose of ethanol or dextrose for the measurements of serum endotoxin and liver pathology, respectively. Compared to the WT, the HIV rats showed increased sensitivity to alcohol-mediated gut leakiness, hepatic steatosis and inflammation, as evidenced with the significantly elevated levels of serum endotoxin, hepatic triglycerides, histological fat accumulation and F4/80 staining. Real-time PCR analysis revealed that hepatic levels of toll-like receptor-4 (TLR4), leptin and the downstream target monocyte chemoattractant protein-1 (MCP-1) were significantly up-regulated in the HIV-EtOH rats, compared to all other groups. Subsequent experiments with primary cultured cells showed that both hepatocytes and hepatic Kupffer cells were the sources of the elevated MCP-1 in HIV-EtOH rats. Further, TLR4 and MCP-1 were found to be upregulated by leptin. Collectively, these results show that HIV rats, similar to HIV-infected people being treated with the highly active anti-retroviral therapy (HAART), are more susceptible to binge alcohol-induced gut leakiness and inflammatory liver disease than the corresponding WT, possibly due to additive or synergistic interaction between binge alcohol exposure and HIV infection. Based on these results, HIV transgenic rats can be used as a surrogate model to study the molecular mechanisms of many disease states caused by heavy alcohol intake in HIV-infected people on HAART. PMID:26484872

  15. Ursolic acid and luteolin-7-glucoside improve lipid profiles and increase liver glycogen content through glycogen synthase kinase-3.

    PubMed

    Azevedo, Marisa F; Camsari, Cagri; Sá, Carla M; Lima, Cristovao F; Fernandes-Ferreira, Manuel; Pereira-Wilson, Cristina

    2010-06-01

    In the present study, two phytochemicals - ursolic acid (UA) and luteolin-7-glucoside (L7G) - were assessed in vivo in healthy rats regarding effects on plasma glucose and lipid profile (total cholesterol, HDL and LDL), as well as liver glycogen content, in view of their importance in the aetiology of diabetes and associated complications. Both UA and L7G significantly decreased plasma glucose concentration. UA also significantly increased liver glycogen levels accompanied by phosphorylation of glycogen synthase kinase-3 (GSK3). The increase in glycogen deposition induced by UA (mediated by GSK3) could have contributed to the lower plasma glucose levels observed. Both compounds significantly lowered total plasma cholesterol and low-density lipoprotein levels, and, in addition, UA increased plasma high-density lipoprotein levels. Our results show that UA particularly may be useful in preventable strategies for people at risk of developing diabetes and associated cardiovascular complications by improving plasma glucose levels and lipid profile, as well as by promoting liver glycogen deposition.

  16. Ursolic acid and luteolin-7-glucoside improve lipid profiles and increase liver glycogen content through glycogen synthase kinase-3.

    PubMed

    Azevedo, Marisa F; Camsari, Cagri; Sá, Carla M; Lima, Cristovao F; Fernandes-Ferreira, Manuel; Pereira-Wilson, Cristina

    2010-06-01

    In the present study, two phytochemicals - ursolic acid (UA) and luteolin-7-glucoside (L7G) - were assessed in vivo in healthy rats regarding effects on plasma glucose and lipid profile (total cholesterol, HDL and LDL), as well as liver glycogen content, in view of their importance in the aetiology of diabetes and associated complications. Both UA and L7G significantly decreased plasma glucose concentration. UA also significantly increased liver glycogen levels accompanied by phosphorylation of glycogen synthase kinase-3 (GSK3). The increase in glycogen deposition induced by UA (mediated by GSK3) could have contributed to the lower plasma glucose levels observed. Both compounds significantly lowered total plasma cholesterol and low-density lipoprotein levels, and, in addition, UA increased plasma high-density lipoprotein levels. Our results show that UA particularly may be useful in preventable strategies for people at risk of developing diabetes and associated cardiovascular complications by improving plasma glucose levels and lipid profile, as well as by promoting liver glycogen deposition. PMID:20127879

  17. Prenatal ethanol exposure programs an increased susceptibility of non-alcoholic fatty liver disease in female adult offspring rats

    SciTech Connect

    Shen, Lang; Liu, Zhongfen; Gong, Jun; Zhang, Li; Wang, Linlong; Magdalou, Jacques; Chen, Liaobin; Wang, Hui

    2014-01-15

    Prenatal ethanol exposure (PEE) induces dyslipidemia and hyperglycemia in fetus and adult offspring. However, whether PEE increases the susceptibility to non-alcoholic fatty liver disease (NAFLD) in offspring and its underlying mechanism remain unknown. This study aimed to demonstrate an increased susceptibility to high-fat diet (HFD)-induced NAFLD and its intrauterine programming mechanisms in female rat offspring with PEE. Rat model of intrauterine growth retardation (IUGR) was established by PEE, the female fetus and adult offspring that fed normal diet (ND) or HFD were sacrificed. The results showed that, in PEE + ND group, serum corticosterone (CORT) slightly decreased and insulin-like growth factor-1 (IGF-1) and glucose increased with partial catch-up growth; In PEE + HFD group, serum CORT decreased, while serum IGF-1, glucose and triglyceride (TG) increased, with notable catch-up growth, higher metabolic status and NAFLD formation. Enhanced liver expression of the IGF-1 pathway, gluconeogenesis, and lipid synthesis as well as reduced expression of lipid output were accompanied in PEE + HFD group. In PEE fetus, serum CORT increased while IGF-1 decreased, with low body weight, hyperglycemia, and hepatocyte ultrastructural changes. Hepatic IGF-1 expression as well as lipid output was down-regulated, while lipid synthesis significantly increased. Based on these findings, we propose a “two-programming” hypothesis for an increased susceptibility to HFD-induced NAFLD in female offspring of PEE. That is, the intrauterine programming of liver glucose and lipid metabolic function is “the first programming”, and postnatal adaptive catch-up growth triggered by intrauterine programming of GC-IGF1 axis acts as “the second programming”. - Highlights: • Prenatal ethanol exposure increase the susceptibility of NAFLD in female offspring. • Prenatal ethanol exposure reprograms fetal liver’s glucose and lipid metabolism . • Prenatal ethanol exposure cause

  18. Ursolic Acid Increases Skeletal Muscle and Brown Fat and Decreases Diet-Induced Obesity, Glucose Intolerance and Fatty Liver Disease

    PubMed Central

    Kunkel, Steven D.; Elmore, Christopher J.; Bongers, Kale S.; Ebert, Scott M.; Fox, Daniel K.; Dyle, Michael C.; Bullard, Steven A.; Adams, Christopher M.

    2012-01-01

    Skeletal muscle Akt activity stimulates muscle growth and imparts resistance to obesity, glucose intolerance and fatty liver disease. We recently found that ursolic acid increases skeletal muscle Akt activity and stimulates muscle growth in non-obese mice. Here, we tested the hypothesis that ursolic acid might increase skeletal muscle Akt activity in a mouse model of diet-induced obesity. We studied mice that consumed a high fat diet lacking or containing ursolic acid. In skeletal muscle, ursolic acid increased Akt activity, as well as downstream mRNAs that promote glucose utilization (hexokinase-II), blood vessel recruitment (Vegfa) and autocrine/paracrine IGF-I signaling (Igf1). As a result, ursolic acid increased skeletal muscle mass, fast and slow muscle fiber size, grip strength and exercise capacity. Interestingly, ursolic acid also increased brown fat, a tissue that shares developmental origins with skeletal muscle. Consistent with increased skeletal muscle and brown fat, ursolic acid increased energy expenditure, leading to reduced obesity, improved glucose tolerance and decreased hepatic steatosis. These data support a model in which ursolic acid reduces obesity, glucose intolerance and fatty liver disease by increasing skeletal muscle and brown fat, and suggest ursolic acid as a potential therapeutic approach for obesity and obesity-related illness. PMID:22745735

  19. Colchicine reduces procollagen III and increases pseudocholinesterase in chronic liver disease

    PubMed Central

    Muntoni, Sergio; Rojkind, Marcos; Muntoni, Sandro

    2010-01-01

    AIM: To test whether colchicine would be an effective antifibrotic agent for treatment of chronic liver diseases in patients who could not be treated with α-interferon. METHODS: Seventy-four patients (46 males, 28 females) aged 40-66 years (mean 53 ± 13 years) participated in the study. The patients were affected by chronic liver diseases with cirrhosis which was proven histologically (n = 58); by chronic active hepatitis C (n = 4), chronic active hepatitis B (n = 2), and chronic persistent hepatitis C (n = 6). In the four patients lacking histology, cirrhosis was diagnosed from anamnesis, serum laboratory tests, esophageal varices and ascites. Patients were assigned to colchicine (1 mg/d) or standard treatment as control in a randomized, double-blind trial, and followed for 4.4 years with clinical and laboratory evaluation. RESULTS: Survival at the end of the study was 94.6% in the colchicine group and 78.4% in the control group (P = 0.001). Serum N-terminal peptide of type III procollagen levels fell from 34.0 to 18.3 ng/mL (P = 0.0001), and pseudocholinesterase levels rose from 4.900 to 5.610 mU/mL (P = 0.0001) in the colchicine group, while no significant change was seen in controls. Best results were obtained in patients with chronic hepatitis C and in alcoholic cirrhotics. CONCLUSION: Colchicine is an effective and safe antifibrotic drug for long-term treatment of chronic liver disease in which fibrosis progresses towards cirrhosis. PMID:20556834

  20. Hepatocyte X-box binding protein 1 deficiency increases liver injury in mice fed a high-fat/sugar diet.

    PubMed

    Liu, Xiaoying; Henkel, Anne S; LeCuyer, Brian E; Schipma, Matthew J; Anderson, Kristy A; Green, Richard M

    2015-12-15

    Fatty liver is associated with endoplasmic reticulum stress and activation of the hepatic unfolded protein response (UPR). Reduced hepatic expression of the UPR regulator X-box binding protein 1 spliced (XBP1s) is associated with human nonalcoholic steatohepatitis (NASH), and feeding mice a high-fat diet with fructose/sucrose causes progressive, fibrosing steatohepatitis. This study examines the role of XBP1 in nonalcoholic fatty liver injury and fatty acid-induced cell injury. Hepatocyte-specific Xbp1-deficient (Xbp1(-/-)) mice were fed a high-fat/sugar (HFS) diet for up to 16 wk. HFS-fed Xbp1(-/-) mice exhibited higher serum alanine aminotransferase levels compared with Xbp1(fl/fl) controls. RNA sequencing and Gene Ontogeny pathway analysis of hepatic mRNA revealed that apoptotic process, inflammatory response, and extracellular matrix structural constituent pathways had enhanced activation in HFS-fed Xbp1(-/-) mice. Liver histology demonstrated enhanced injury and fibrosis but less steatosis in the HFS-fed Xbp1(-/-) mice. Hepatic Col1a1 and Tgfβ1 gene expression, as well as Chop and phosphorylated JNK (p-JNK), were increased in Xbp1(-/-) compared with Xbp1(fl/fl) mice after HFS feeding. In vitro, stable XBP1-knockdown Huh7 cells (Huh7-KD) and scramble control cells (Huh7-SCR) were generated and treated with palmitic acid (PA) for 24 h. PA-treated Huh7-KD cells had increased cytotoxicity measured by lactate dehydrogenase release, apoptotic nuclei, and caspase3/7 activity assays compared with Huh7-SCR cells. CHOP and p-JNK expression was also increased in Huh7-KD cells following PA treatment. In conclusion, loss of XBP1 enhances injury in both in vivo and in vitro models of fatty liver injury. We speculate that hepatic XBP1 plays an important protective role in pathogenesis of NASH.

  1. Hepatocyte X-box binding protein 1 deficiency increases liver injury in mice fed a high-fat/sugar diet.

    PubMed

    Liu, Xiaoying; Henkel, Anne S; LeCuyer, Brian E; Schipma, Matthew J; Anderson, Kristy A; Green, Richard M

    2015-12-15

    Fatty liver is associated with endoplasmic reticulum stress and activation of the hepatic unfolded protein response (UPR). Reduced hepatic expression of the UPR regulator X-box binding protein 1 spliced (XBP1s) is associated with human nonalcoholic steatohepatitis (NASH), and feeding mice a high-fat diet with fructose/sucrose causes progressive, fibrosing steatohepatitis. This study examines the role of XBP1 in nonalcoholic fatty liver injury and fatty acid-induced cell injury. Hepatocyte-specific Xbp1-deficient (Xbp1(-/-)) mice were fed a high-fat/sugar (HFS) diet for up to 16 wk. HFS-fed Xbp1(-/-) mice exhibited higher serum alanine aminotransferase levels compared with Xbp1(fl/fl) controls. RNA sequencing and Gene Ontogeny pathway analysis of hepatic mRNA revealed that apoptotic process, inflammatory response, and extracellular matrix structural constituent pathways had enhanced activation in HFS-fed Xbp1(-/-) mice. Liver histology demonstrated enhanced injury and fibrosis but less steatosis in the HFS-fed Xbp1(-/-) mice. Hepatic Col1a1 and Tgfβ1 gene expression, as well as Chop and phosphorylated JNK (p-JNK), were increased in Xbp1(-/-) compared with Xbp1(fl/fl) mice after HFS feeding. In vitro, stable XBP1-knockdown Huh7 cells (Huh7-KD) and scramble control cells (Huh7-SCR) were generated and treated with palmitic acid (PA) for 24 h. PA-treated Huh7-KD cells had increased cytotoxicity measured by lactate dehydrogenase release, apoptotic nuclei, and caspase3/7 activity assays compared with Huh7-SCR cells. CHOP and p-JNK expression was also increased in Huh7-KD cells following PA treatment. In conclusion, loss of XBP1 enhances injury in both in vivo and in vitro models of fatty liver injury. We speculate that hepatic XBP1 plays an important protective role in pathogenesis of NASH. PMID:26472223

  2. Elevated oxidative stress, iron accumulation around microvessels and increased 4-hydroxynonenal immunostaining in zone 1 of the liver acinus in hypercholesterolemic rabbits.

    PubMed

    Ong, Wei-Yi; Jenner, Andrew M; Pan, Ning; Ong, Choon-Nam; Halliwell, Barry

    2009-03-01

    Rabbits were fed a diet containing 1% cholesterol for 8 weeks and the levels of iron and oxidized lipids in liver analysed using atomic absorption spectroscopy and gas chromatography-mass spectrometry. A non-significant trend to an increase in iron level, but significant increases in the lipid peroxidation products, F(2)-isoprostanes and the cholesterol oxidation products 7 beta hydroxycholesterol, 7 ketocholesterol and cholesterol 5,6-alpha epoxide were detected in the liver of the cholesterol-fed rabbits. Histological analysis showed greater accumulation of lipids by Sudan red labelling in hepatocytes of zone I than zones II and III of the liver acinus. The increase in lipids coincided with an increase in iron staining in macrophages around liver microvessels and increased immunostaining to melanotransferrin and the lipid peroxidation product, 4-hydroxynonenal (4-HNE), in zone 1. The results are suggestive of microvascular damage associated with iron accumulation and oxidative stress in the liver during hypercholesterolemia.

  3. Prenatal ethanol exposure programs an increased susceptibility of non-alcoholic fatty liver disease in female adult offspring rats.

    PubMed

    Shen, Lang; Liu, Zhongfen; Gong, Jun; Zhang, Li; Wang, Linlong; Magdalou, Jacques; Chen, Liaobin; Wang, Hui

    2014-01-15

    Prenatal ethanol exposure (PEE) induces dyslipidemia and hyperglycemia in fetus and adult offspring. However, whether PEE increases the susceptibility to non-alcoholic fatty liver disease (NAFLD) in offspring and its underlying mechanism remain unknown. This study aimed to demonstrate an increased susceptibility to high-fat diet (HFD)-induced NAFLD and its intrauterine programming mechanisms in female rat offspring with PEE. Rat model of intrauterine growth retardation (IUGR) was established by PEE, the female fetus and adult offspring that fed normal diet (ND) or HFD were sacrificed. The results showed that, in PEE+ND group, serum corticosterone (CORT) slightly decreased and insulin-like growth factor-1 (IGF-1) and glucose increased with partial catch-up growth; In PEE+HFD group, serum CORT decreased, while serum IGF-1, glucose and triglyceride (TG) increased, with notable catch-up growth, higher metabolic status and NAFLD formation. Enhanced liver expression of the IGF-1 pathway, gluconeogenesis, and lipid synthesis as well as reduced expression of lipid output were accompanied in PEE+HFD group. In PEE fetus, serum CORT increased while IGF-1 decreased, with low body weight, hyperglycemia, and hepatocyte ultrastructural changes. Hepatic IGF-1 expression as well as lipid output was down-regulated, while lipid synthesis significantly increased. Based on these findings, we propose a "two-programming" hypothesis for an increased susceptibility to HFD-induced NAFLD in female offspring of PEE. That is, the intrauterine programming of liver glucose and lipid metabolic function is "the first programming", and postnatal adaptive catch-up growth triggered by intrauterine programming of GC-IGF1 axis acts as "the second programming".

  4. Sphingosine kinase-1, S1P transporter spinster homolog 2 and S1P2 mRNA expressions are increased in liver with advanced fibrosis in human

    PubMed Central

    Sato, Masaya; Ikeda, Hitoshi; Uranbileg, Baasanjav; Kurano, Makoto; Saigusa, Daisuke; Aoki, Junken; Maki, Harufumi; Kudo, Hiroki; Hasegawa, Kiyoshi; Kokudo, Norihiro; Yatomi, Yutaka

    2016-01-01

    The role of sphingosine 1-phosphate (S1P) in liver fibrosis or inflammation was not fully examined in human. Controversy exists which S1P receptors, S1P1 and S1P3 vs S1P2, would be importantly involved in its mechanism. To clarify these matters, 80 patients who received liver resection for hepatocellular carcinoma and 9 patients for metastatic liver tumor were enrolled. S1P metabolism was analyzed in background, non-tumorous liver tissue. mRNA levels of sphingosine kinase 1 (SK1) but not SK2 were increased in livers with fibrosis stages 3–4 compared to those with 0–2 and to normal liver. However, S1P was not increased in advanced fibrotic liver, where mRNA levels of S1P transporter spinster homolog 2 (SPNS2) but not S1P-degrading enzymes were enhanced. Furthermore, mRNA levels of S1P2 but not S1P1 or S1P3 were increased in advanced fibrotic liver. These increased mRNA levels of SK1, SPNS2 and S1P2 in fibrotic liver were correlated with α-smooth muscle actin mRNA levels in liver, and with serum ALT levels. In conclusion, S1P may be actively generated, transported to outside the cells, and bind to its specific receptor in human liver to play a role in fibrosis or inflammation. Altered S1P metabolism in fibrotic liver may be their therapeutic target. PMID:27562371

  5. Sphingosine kinase-1, S1P transporter spinster homolog 2 and S1P2 mRNA expressions are increased in liver with advanced fibrosis in human.

    PubMed

    Sato, Masaya; Ikeda, Hitoshi; Uranbileg, Baasanjav; Kurano, Makoto; Saigusa, Daisuke; Aoki, Junken; Maki, Harufumi; Kudo, Hiroki; Hasegawa, Kiyoshi; Kokudo, Norihiro; Yatomi, Yutaka

    2016-01-01

    The role of sphingosine 1-phosphate (S1P) in liver fibrosis or inflammation was not fully examined in human. Controversy exists which S1P receptors, S1P1 and S1P3 vs S1P2, would be importantly involved in its mechanism. To clarify these matters, 80 patients who received liver resection for hepatocellular carcinoma and 9 patients for metastatic liver tumor were enrolled. S1P metabolism was analyzed in background, non-tumorous liver tissue. mRNA levels of sphingosine kinase 1 (SK1) but not SK2 were increased in livers with fibrosis stages 3-4 compared to those with 0-2 and to normal liver. However, S1P was not increased in advanced fibrotic liver, where mRNA levels of S1P transporter spinster homolog 2 (SPNS2) but not S1P-degrading enzymes were enhanced. Furthermore, mRNA levels of S1P2 but not S1P1 or S1P3 were increased in advanced fibrotic liver. These increased mRNA levels of SK1, SPNS2 and S1P2 in fibrotic liver were correlated with α-smooth muscle actin mRNA levels in liver, and with serum ALT levels. In conclusion, S1P may be actively generated, transported to outside the cells, and bind to its specific receptor in human liver to play a role in fibrosis or inflammation. Altered S1P metabolism in fibrotic liver may be their therapeutic target. PMID:27562371

  6. Polyphenols decreased liver NADPH oxidase activity, increased muscle mitochondrial biogenesis and decreased gastrocnemius age-dependent autophagy in aged rats.

    PubMed

    Laurent, Caroline; Chabi, Beatrice; Fouret, Gilles; Py, Guillaume; Sairafi, Badie; Elong, Cecile; Gaillet, Sylvie; Cristol, Jean Paul; Coudray, Charles; Feillet-Coudray, Christine

    2012-09-01

    This study explored major systems of reactive oxygen species (ROS) production and their consequences on oxidative stress, mitochondriogenesis and muscle metabolism in aged rats, and evaluated the efficiency of 30-day oral supplementation with a moderate dose of a red grape polyphenol extract (RGPE) on these parameters. In the liver of aged rats, NADPH oxidase activity was increased and mitochondrial respiratory chain complex activities were altered, while xanthine oxidase activity remained unchanged. In muscles, only mitochondrial activity was modified with aging. The oral intake of RGPE decreased liver NADPH oxidase activity in the aged rats without affecting global oxidative stress, suggesting that NADPH oxidase was probably not the dominant detrimental source of production of O(2)·(-) in the liver. Interestingly, RGPE supplementation increased mitochondrial biogenesis and improved antioxidant status in the gastrocnemius of aged rats, while it had no significant effect in soleus. RGPE supplementation also decreased age-dependent autophagy in gastrocnemius of aged rats. These results extended existing findings on the beneficial effects of RGPE on mitochondriogenesis and muscle metabolism in aged rats.

  7. Increasing concentrations of prothrombin complex concentrate induce disseminated intravascular coagulation in a pig model of coagulopathy with blunt liver injury.

    PubMed

    Grottke, Oliver; Braunschweig, Till; Spronk, Henri M H; Esch, Stephanie; Rieg, Annette D; van Oerle, Rene; ten Cate, Hugo; Fitzner, Christina; Tolba, Rene; Rossaint, Rolf

    2011-08-18

    Despite increasing use of prothrombin complex concentrate (PCC) to treat hemorrhage-associated coagulopathy, few studies have investigated PCC in trauma, and there is a particular lack of safety data. This study was performed to evaluate PCC therapy in a porcine model of coagulopathy with blunt liver injury. Coagulopathy was induced in 27 anesthetized pigs by replacing approximately 70% blood volume with hydroxyethyl starch 130/0.4 and Ringer's lactate solution; erythrocytes were collected and retransfused. Ten minutes after trauma, animals randomly received PCC (35 or 50 IU/kg) or saline. Coagulation parameters including thromboelastometry, thrombin generation, and blood loss were monitored for 2 hours. Internal organs were examined macroscopically and histologically to determine the presence of emboli and assess liver injury. Total blood loss was significantly lower and survival was higher in both PCC groups versus the control group (P < .05). These outcomes appeared to be dose-independent. Thromboembolism was found in all animals treated with 50 IU/kg PCC; 44% also showed signs of disseminated intravascular coagulation. Liver injury was similar in all animals. In conclusion, 35 IU/kg PCC safely improved coagulation and attenuated blood loss. However, the higher dose of PCC (50 IU/kg) appeared to increase the risk of thromboembolism and disseminated intravascular coagulation.

  8. Obesity increases histone H3 lysine 9 and 18 acetylation at Tnfa and Ccl2 genes in mouse liver.

    PubMed

    Mikula, Michal; Majewska, Aneta; Ledwon, Joanna Karolina; Dzwonek, Artur; Ostrowski, Jerzy

    2014-12-01

    Obesity contributes to the development of non-alcoholic fatty liver disease (NAFLD), which is characterized by the upregulated expression of two key inflammatory mediators: tumor necrosis factor (Tnfa) and monocyte chemotactic protein 1 (Mcp1; also known as Ccl2). However, the chromatin make-up at these genes in the liver in obese individuals has not been explored. In this study, to identify obesity-mediated epigenetic changes at Tnfa and Ccl2, we used a murine model of obesity induced by a high-fat diet (HFD) and hyperphagic (ob/ob) mice. Chromatin immunoprecipitation (ChIP) assay was used to determine the abundance of permissive histone marks, namely histone H3 lysine 9 and 18 acetylation (H3K9/K18Ac), H3 lysine 4 trimethylation (H3K4me3) and H3 lysine 36 trimethylation (H3K36me3), in conjunction with polymerase 2 RNA (Pol2) and nuclear factor (Nf)-κB recruitment in the liver. Additionally, to correlate the liver tissue-derived ChIP measurements with a robust in vitro transcriptional response at the Tnfa and Ccl2 genes, we used lipopolysaccharide (LPS) treatment to induce an inflammatory response in Hepa1-6 cells, a cell line derived from murine hepatocytes. ChIP revealed increased H3K9/K18Ac at Tnfa and Ccl2 in the obese mice, although the differences were only statistically significant for Tnfa (p<0.05). Unexpectedly, the levels of H3K4me3 and H3K36me3 marks, as well as Pol2 and Nf-κB recruitment, did not correspond with the increased expression of these two genes in the obese mice. By contrast, the acute treatment of Hepa1-6 cells with LPS significantly increased the H3K9/K18Ac marks, as well as Pol2 and Nf-κB recruitment at both genes, while the levels of H3K4me3 and H3K36me3 marks remained unaltered. These results demonstrate that increased Tnfa and Ccl2 expression in fatty liver at the chromatin level corresponds to changes in the level of histone H3 acetylation.

  9. Increased whole-body adiposity without a concomitant increase in liver fat is not associated with augmented metabolic dysfunction.

    PubMed

    Magkos, Faidon; Fabbrini, Elisa; Mohammed, B Selma; Patterson, Bruce W; Klein, Samuel

    2010-08-01

    Aim of this study was to determine whether an increase in adiposity, without a concomitant increase in intrahepatic triglyceride (IHTG) content, is associated with a deterioration in metabolic function. To this end, multiorgan insulin sensitivity, assessed by using a two-stage hyperinsulinemic-euglycemic clamp procedure in conjunction with stable isotopically labeled tracer infusion, and very low-density lipoprotein (VLDL) kinetics, assessed by using stable isotopically labeled tracer infusion and mathematical modeling, were determined in 10 subjects with class I obesity (BMI: 31.6 +/- 0.3 kg/m(2); 37 +/- 2% body fat; visceral adipose tissue (VAT): 1,225 +/- 144 cm(3)) and 10 subjects with class III obesity (BMI: 41.5 +/- 0.5 kg/m(2); 43 +/- 2% body fat; VAT: 2,121 +/- 378 cm(3)), matched on age, sex, and IHTG content (14 +/- 4 and 14 +/- 3%, respectively). No differences between class I and class III obese groups were detected in insulin-mediated suppression of palmitate (67 +/- 3 and 65 +/- 3%, respectively; P = 0.635) and glucose (67 +/- 3 and 73 +/- 5%, respectively; P = 0.348) rates of appearance in plasma, and the insulin-mediated increase in glucose disposal (218 +/- 18 and 193 +/- 30%, respectively; P = 0.489). In addition, no differences between class I and class III obese groups were detected in secretion rates of VLDL-triglyceride (6.5 +/- 1.0 and 6.0 +/- 1.4 micromol/l x min, respectively; P = 0.787) and VLDL-apolipoprotein B-100 (0.40 +/- 0.05 and 0.41 +/- 0.04 nmol/l x min, respectively; P = 0.866), and plasma clearance rates of VLDL-triglyceride (31 (16-59) and 29 (18-46) ml/min, respectively; P = 0.888) and VLDL-apolipoprotein B-100 (15 (11-19) and 17 (11-25) ml/min, respectively; P = 0.608). We conclude that increased adiposity without a concomitant increase in IHTG content does not cause additional abnormalities in adipose tissue, skeletal muscle, and hepatic insulin sensitivity, or VLDL metabolism. PMID:20395947

  10. Different collagen types show distinct rates of increase from early to late stages of hepatitis C-related liver fibrosis.

    PubMed

    Chen, Wei; Rock, Jonathan B; Yearsley, Martha M; Ferrell, Linda D; Frankel, Wendy L

    2014-01-01

    During progression from normal liver to cirrhosis, total collagen increases nearly 10-fold with an abnormal increase in fibril-forming collagen and other extracellular matrix molecules. However, little is known regarding the changes each collagen type undergoes during fibrogenesis. We assessed the different collagen types by immunohistochemistry at various stages of hepatitis C-related liver fibrosis in core biopsies and compared changes in each with trichrome stain to better understand fibrogenesis. The possible utility in staging fibrosis was investigated. We found collagens III, IV, V, VI, vitronectin, and trichrome all showed statistically significant increases from early to late stages of fibrosis, but with temporal and quantitative differences. During the transition from early to late fibrosis, trichrome (stains primarily collagen I) and collagen IV showed the steepest increase and appear to be the most useful discriminators between early and late stages of fibrosis. Collagens V and VI have strong reactivity even in stage 1, which may be helpful in identifying early fibrosis when trichrome is weak or negative. Collagen III and vitronectin showed the most gradual increase. Interestingly, collagen V also showed increased staining in areas around inflammation/edema, which may overestimate established fibrosis as compared with trichrome.

  11. Increased mortality odds ratio of male liver cancer in a community contaminated by chlorinated hydrocarbons in groundwater

    PubMed Central

    Lee, L; Chung, C; Ma, Y; Wang, G; Chen, P; Hwang, Y; Wang, J

    2003-01-01

    Aims: To investigate the association between cancer mortality risk and exposure to chlorinated hydrocarbons in groundwater of a downstream community near a contaminated site. Methods: Death certificates inclusive for the years 1966–97 were collected from two villages in the vicinity of an electronics factory operated between 1970 and 1992. These two villages were classified into the downstream (exposed) village and the upstream (unexposed) according to groundwater flow direction. Exposure classification was validated by the contaminant levels in 49 residential wells measured with gas chromatography/mass spectrometry. Mortality odds ratios (MORs) for cancer were calculated with cardiovascular-cerebrovascular diseases as the reference diseases. Multiple logistic regressions were performed to estimate the effects of exposure and period after adjustment for age. Results: Increased MORs were observed among males for all cancer, and liver cancer for the periods after 10 years of latency, namely, 1980–89, and 1990–97. Adjusted MOR for male liver cancer was 2.57 (95% confidence interval 1.21 to 5.46) with a significant linear trend for the period effect. Conclusion: The results suggest a link between exposure to chlorinated hydrocarbons and male liver cancer risk. However, the conclusion is limited by lack of individual information on groundwater exposure and potential confounding factors. PMID:12709523

  12. A High-Fat, High-Fructose Diet Induces Antioxidant Imbalance and Increases the Risk and Progression of Nonalcoholic Fatty Liver Disease in Mice.

    PubMed

    Jarukamjorn, Kanokwan; Jearapong, Nattharat; Pimson, Charinya; Chatuphonprasert, Waranya

    2016-01-01

    Excessive fat liver is an important manifestation of nonalcoholic fatty liver disease (NAFLD), associated with obesity, insulin resistance, and oxidative stress. In the present study, the effects of a high-fat, high-fructose diet (HFFD) on mRNA levels and activities of the antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), were determined in mouse livers and brains. The histomorphology of the livers was examined and the state of nonenzymatic reducing system was evaluated by measuring the glutathione system and the lipid peroxidation. Histopathology of the liver showed that fat accumulation and inflammation depended on the period of the HFFD-consumption. The levels of mRNA and enzymatic activities of SOD, CAT, and GPx were raised, followed by the increases in malondialdehyde levels in livers and brains of the HFFD mice. The oxidized GSSG content was increased while the total GSH and the reduced GSH were decreased, resulting in the increase in the GSH/GSSG ratio in both livers and brains of the HFFD mice. These observations suggested that liver damage and oxidative stress in the significant organs were generated by continuous HFFD-consumption. Imbalance of antioxidant condition induced by long-term HFFD-consumption might increase the risk and progression of NAFLD.

  13. A High-Fat, High-Fructose Diet Induces Antioxidant Imbalance and Increases the Risk and Progression of Nonalcoholic Fatty Liver Disease in Mice

    PubMed Central

    Jearapong, Nattharat; Pimson, Charinya; Chatuphonprasert, Waranya

    2016-01-01

    Excessive fat liver is an important manifestation of nonalcoholic fatty liver disease (NAFLD), associated with obesity, insulin resistance, and oxidative stress. In the present study, the effects of a high-fat, high-fructose diet (HFFD) on mRNA levels and activities of the antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), were determined in mouse livers and brains. The histomorphology of the livers was examined and the state of nonenzymatic reducing system was evaluated by measuring the glutathione system and the lipid peroxidation. Histopathology of the liver showed that fat accumulation and inflammation depended on the period of the HFFD-consumption. The levels of mRNA and enzymatic activities of SOD, CAT, and GPx were raised, followed by the increases in malondialdehyde levels in livers and brains of the HFFD mice. The oxidized GSSG content was increased while the total GSH and the reduced GSH were decreased, resulting in the increase in the GSH/GSSG ratio in both livers and brains of the HFFD mice. These observations suggested that liver damage and oxidative stress in the significant organs were generated by continuous HFFD-consumption. Imbalance of antioxidant condition induced by long-term HFFD-consumption might increase the risk and progression of NAFLD. PMID:27019761

  14. Extracorporeal support for patients with acute and acute on chronic liver failure.

    PubMed

    Aron, Jonathan; Agarwal, Banwari; Davenport, Andrew

    2016-01-01

    The number of patients developing liver failure; acute on chronic liver failure and acute liver failure continues to increase, along with the demand for donor livers for transplantation. As such there is a clinical need to develop effective extracorporeal devices to support patients with acute liver failure or acute-on-chronic liver failure to allow time for hepatocyte regeneration, and so avoiding the need for liver transplantation, or to bridge the patient to liver transplantation, and also potentially to provide symptomatic relief for patients with cirrhosis not suitable for transplantation. Currently devices can be divided into those designed to remove toxins, including plasma exchange, high permeability dialyzers and adsorption columns or membranes, coupled with replacement of plasma proteins; albumin dialysis systems; and bioartificial devices which may provide some of the biological functions of the liver. In the future we expect combinations of these devices in clinical practice, due to the developments in bioartificial scaffolds.

  15. Increase of annexin 1 immunoreactivity in spinal cord of newborn opossum (Monodelphis domestica) at the time when regeneration after injury stops being possible.

    PubMed

    Mladinic, M; Del Bel, E; Nicholls, J

    2007-11-01

    Annexins constitute a family of proteins that associate reversibly with cell membranes in a calcium dependent manner. We have studied the distribution of annexin 1, which is known to mediate anti-inflammatory actions of glucocorticoids, and which is upregulated after spinal cord injury, in newborn and adult South American opossum (Monodelphis domestica) spinal cord. We show the increase in the annexin 1 immunoreactivity in spinal cords of neonatal opossums over the critical period when regeneration after injury ceases to be possible. We further show the restricted and specific sites at which it is detected in adult opossum cerebellum and hippocampus. Since the procedures used in immunochemistry of annexin in CNS have in the past yielded conflicting results, different procedures were tested and shown to be reliable. As a control, annexin 1 distribution was surveyed in kidney.

  16. Statins Increase Mitochondrial and Peroxisomal Fatty Acid Oxidation in the Liver and Prevent Non-Alcoholic Steatohepatitis in Mice

    PubMed Central

    Park, Han-Sol; Jang, Jung Eun; Ko, Myoung Seok; Woo, Sung Hoon; Kim, Bum Joong; Kim, Hyun Sik; Park, Hye Sun; Park, In-Sun; Koh, Eun Hee

    2016-01-01

    Background Non-alcoholic fatty liver disease is the most common form of chronic liver disease in industrialized countries. Recent studies have highlighted the association between peroxisomal dysfunction and hepatic steatosis. Peroxisomes are intracellular organelles that contribute to several crucial metabolic processes, such as facilitation of mitochondrial fatty acid oxidation (FAO) and removal of reactive oxygen species through catalase or plasmalogen synthesis. Statins are known to prevent hepatic steatosis and non-alcoholic steatohepatitis (NASH), but underlying mechanisms of this prevention are largely unknown. Methods Seven-week-old C57BL/6J mice were given normal chow or a methionine- and choline-deficient diet (MCDD) with or without various statins, fluvastatin, pravastatin, simvastatin, atorvastatin, and rosuvastatin (15 mg/kg/day), for 6 weeks. Histological lesions were analyzed by grading and staging systems of NASH. We also measured mitochondrial and peroxisomal FAO in the liver. Results Statin treatment prevented the development of MCDD-induced NASH. Both steatosis and inflammation or fibrosis grades were significantly improved by statins compared with MCDD-fed mice. Gene expression levels of peroxisomal proliferator-activated receptor α (PPARα) were decreased by MCDD and recovered by statin treatment. MCDD-induced suppression of mitochondrial and peroxisomal FAO was restored by statins. Each statin's effect on increasing FAO and improving NASH was independent on its effect of decreasing cholesterol levels. Conclusion Statins prevented NASH and increased mitochondrial and peroxisomal FAO via induction of PPARα. The ability to increase hepatic FAO is likely the major determinant of NASH prevention by statins. Improvement of peroxisomal function by statins may contribute to the prevention of NASH.

  17. Kinetics of 3H-thymidine label in rat liver regenerating after partial hepatectomy and after damage with carbon tetrachloride or silica.

    PubMed

    Kanta, J; Chmelar, V

    1989-01-01

    Rat liver DNA was labelled with [methyl-3H] thymidine after partial hepatectomy, carbon tetrachloride poisoning, or an intravenous injection of silica dust. Changes in DNA labelling were studied for 4 weeks after the single pulse. Total radioactivity incorporated into liver DNA after partial hepatectomy and after carbon tetrachloride administration remained on the same level when compared with that found after 1 h. DNA activity in liver of untreated rats and of rats treated with silica decreased by about 50% within the first 2 weeks and then remained on this level for the rest of the studied period. These differences may reflect the fact that hepatocytes that have a long life span are preferentially labelled in partially hepatectomized and CCl4-treated rats, while liver macrophages with a short half-life take up a large part of the label in intact rats and in rats treated with silica.

  18. High-fat diet intake accelerates aging, increases expression of Hsd11b1, and promotes lipid accumulation in liver of SAMP10 mouse.

    PubMed

    Honma, Taro; Shinohara, Nahoko; Ito, Junya; Kijima, Ryo; Sugawara, Soko; Arai, Tatsuya; Tsuduki, Tsuyoshi; Ikeda, Ikuo

    2012-04-01

    An understanding of the mechanisms of aging is important for prevention of age-related diseases. In this study, we examined age-dependent changes in lipid metabolism in the senescence-accelerated mouse (SAM)P10 fed a high-fat diet to investigate the effects of high-fat intake and aging. Tissue weights and biological parameters in plasma and liver were measured at 6 and 12 months old in SAMP10 mice fed a high-fat diet. These mice showed marked increases in liver triacylglycerol and plasma insulin levels with intake of a high-fat diet intake and aging. Lipid accumulation in hepatocytes and morphological aberrations and hypertrophy in pancreatic islets were also promoted by a high-fat diet and aging. To investigate the underlying mechanisms, the activities and mRNA levels for enzymes associated with lipid metabolism in liver were measured. The results indicated that the lipid metabolic system was activated by a high-fat diet and aging. Liver mRNA level for hydroxysteroid 11-beta dehydrogenase 1 (Hsd11b1), which exhibit age-dependent increases and promote insulin secretion, was also markedly increased. These results suggest that a high-fat diet accelerated aging in the liver of SAMP10 mice by increasing liver mRNA level for Hsd11b1, increasing insulin secretion, and promoting lipid accumulation in the liver.

  19. Precision-cut liver slices from diet-induced obese rats exposed to ethanol are susceptible to oxidative stress and increased fatty acid synthesis

    PubMed Central

    Willis, Monte S.; Schaffert, Courtney S.; Reidelberger, Roger D.; Dusad, Anand; Anderson, Daniel R.; Klassen, Lynell W.; Thiele, Geoffrey M.

    2013-01-01

    Oxidative stress from fat accumulation in the liver has many deleterious effects. Many believe that there is a second hit that causes relatively benign fat accumulation to transform into liver failure. Therefore, we evaluated the effects of ethanol on ex vivo precision-cut liver slice cultures (PCLS) from rats fed a high-fat diet resulting in fatty liver. Age-matched male Sprague-Dawley rats were fed either high-fat (obese) (45% calories from fat, 4.73 kcal/g) or control diet for 13 mo. PCLS were prepared, incubated with 25 mM ethanol for 24, 48, and 72 h, harvested, and evaluated for ethanol metabolism, triglyceride production, oxidative stress, and cytokine expression. Ethanol metabolism and acetaldehyde production decreased in PCLS from obese rats compared with age-matched controls (AMC). Increased triglyceride and smooth muscle actin production was observed in PCLS from obese rats compared with AMC, which further increased following ethanol incubation. Lipid peroxidation, measured by thiobarbituric acid reactive substances assay, increased in response to ethanol, whereas GSH and heme oxygenase I levels were decreased. TNF-α and IL-6 levels were increased in the PCLS from obese rats and increased further with ethanol incubation. Diet-induced fatty liver increases the susceptibility of the liver to toxins such as ethanol, possibly by the increased oxidative stress and cytokine production. These findings support the concept that the development of fatty liver sensitizes the liver to the effects of ethanol and leads to the start of liver failure, necrosis, and eventually cirrhosis. PMID:24284960

  20. Precision-cut liver slices from diet-induced obese rats exposed to ethanol are susceptible to oxidative stress and increased fatty acid synthesis.

    PubMed

    Duryee, Michael J; Willis, Monte S; Schaffert, Courtney S; Reidelberger, Roger D; Dusad, Anand; Anderson, Daniel R; Klassen, Lynell W; Thiele, Geoffrey M

    2014-02-01

    Oxidative stress from fat accumulation in the liver has many deleterious effects. Many believe that there is a second hit that causes relatively benign fat accumulation to transform into liver failure. Therefore, we evaluated the effects of ethanol on ex vivo precision-cut liver slice cultures (PCLS) from rats fed a high-fat diet resulting in fatty liver. Age-matched male Sprague-Dawley rats were fed either high-fat (obese) (45% calories from fat, 4.73 kcal/g) or control diet for 13 mo. PCLS were prepared, incubated with 25 mM ethanol for 24, 48, and 72 h, harvested, and evaluated for ethanol metabolism, triglyceride production, oxidative stress, and cytokine expression. Ethanol metabolism and acetaldehyde production decreased in PCLS from obese rats compared with age-matched controls (AMC). Increased triglyceride and smooth muscle actin production was observed in PCLS from obese rats compared with AMC, which further increased following ethanol incubation. Lipid peroxidation, measured by thiobarbituric acid reactive substances assay, increased in response to ethanol, whereas GSH and heme oxygenase I levels were decreased. TNF-α and IL-6 levels were increased in the PCLS from obese rats and increased further with ethanol incubation. Diet-induced fatty liver increases the susceptibility of the liver to toxins such as ethanol, possibly by the increased oxidative stress and cytokine production. These findings support the concept that the development of fatty liver sensitizes the liver to the effects of ethanol and leads to the start of liver failure, necrosis, and eventually cirrhosis.

  1. Increased oxidative stress response in granulocytes from older patients with a hip fracture may account for slow regeneration.

    PubMed

    Wang, Zhiyong; Ehnert, Sabrina; Ihle, Christoph; Schyschka, Lilianna; Pscherer, Stefan; Nussler, Natascha C; Braun, Karl F; Van Griensven, Martijn; Wang, Guobin; Burgkart, Rainer; Stöckle, Ulrich; Gebhard, Florian; Vester, Helen; Nussler, Andreas K

    2014-01-01

    Proximal femur fracture, a typical fracture of the elderly, is often associated with morbidity, reduced quality of life, impaired physical function and increased mortality. There exists evidence that responses of the hematopoietic microenvironment to fractures change with age. Therefore, we investigated oxidative stress markers and oxidative stress-related MAPK activation in granulocytes from the young and the elderly with and without fractured long bones. Lipid peroxidation levels were increased in the elderly controls and patients. Aged granulocytes were more sensitive towards oxidative stress induced damage than young granulocytes. This might be due to the basally increased expression of SOD-1 in the elderly, which was not further induced by fractures, as observed in young patients. This might be caused by an altered MAPK activation. In aged granulocytes basal p38 and JNK activities were increased and basal ERK1/2 activity was decreased. Following fracture, JNK activity decreased, while ERK1/2 and p38 activities increased in both age groups. Control experiments with HL60 cells revealed that the observed p38 activation depends strongly on age. Summarizing, we observed age-dependent changes in the oxidative stress response system of granulocytes after fractures, for example, altered MAPK activation and SOD-1 expression. This makes aged granulocytes vulnerable to the stress stimuli of the fracture and following surgery.

  2. Mice with hepatocyte-specific deficiency of type 3 deiodinase have intact liver regeneration and accelerated recovery from nonthyroidal illness after toxin-induced hepatonecrosis.

    PubMed

    Castroneves, Luciana A; Jugo, Rebecca H; Maynard, Michelle A; Lee, Jennifer S; Wassner, Ari J; Dorfman, David; Bronson, Roderick T; Ukomadu, Chinweike; Agoston, Agoston T; Ding, Lai; Luongo, Cristina; Guo, Cuicui; Song, Huaidong; Demchev, Valeriy; Lee, Nicholas Y; Feldman, Henry A; Vella, Kristen R; Peake, Roy W; Hartigan, Christina; Kellogg, Mark D; Desai, Anal; Salvatore, Domenico; Dentice, Monica; Huang, Stephen A

    2014-10-01

    Type 3 deiodinase (D3), the physiologic inactivator of thyroid hormones, is induced during tissue injury and regeneration. This has led to the hypotheses that D3 impacts injury tolerance by reducing local T3 signaling and contributes to the fall in serum triiodothyronine (T3) observed in up to 75% of sick patients (termed the low T3 syndrome). Here we show that a novel mutant mouse with hepatocyte-specific D3 deficiency has normal local responses to toxin-induced hepatonecrosis, including normal degrees of tissue necrosis and intact regeneration, but accelerated systemic recovery from illness-induced hypothyroxinemia and hypotriiodothyroninemia, demonstrating that peripheral D3 expression is a key modulator of the low T3 syndrome.

  3. A novel, dynamic pattern-based analysis of NF-κB binding during the priming phase of liver regeneration reveals switch-like functional regulation of target genes

    PubMed Central

    Cook, Daniel J.; Patra, Biswanath; Kuttippurathu, Lakshmi; Hoek, Jan B.; Vadigepalli, Rajanikanth

    2015-01-01

    Following partial hepatectomy, a coordinated series of molecular events occurs to regulate hepatocyte entry into the cell cycle to recover lost mass. In rats during the first 6 h following resection, hepatocytes are primed by a tightly controlled cytokine response to prepare hepatocytes to begin replication. Although it appears to be a critical element driving regeneration, the cytokine response to resection has not yet been fully characterized. Specifically, the role of one of the key response elements to cytokine signaling (NF-κB) remains incompletely characterized. In this study, we present a novel, genome-wide, pattern-based analysis characterizing NF-κB binding during the priming phase of liver regeneration. We interrogated the dynamic regulation of priming by NF-κB through categorizing NF-κB binding in different temporal profiles: immediate sustained response, early transient response, and delayed response to partial hepatectomy. We then identified functional regulation of NF-κB binding by relating the temporal response profile to differential gene expression. We found that NF-κB bound genes govern negative regulation of cell growth and inflammatory response immediately following hepatectomy. NF-κB also transiently regulates genes responsible for lipid biosynthesis and transport as well as induction of apoptosis following hepatectomy. By the end of the priming phase, NF-κB regulation of genes involved in inflammatory response, negative regulation of cell death, and extracellular structure organization became prominent. These results suggest that NF-κB regulates target genes through binding and unbinding in immediate, transient, and delayed patterns. Such dynamic switch-like patterns of NF-κB binding may govern different functional transitions that drive the onset of regeneration. PMID:26217230

  4. Expression of Stromal Cell-Derived Factor-1 and of Its Receptor CXCR4 in Liver Regeneration from Oval Cells in Rat

    PubMed Central

    Mavier, Philippe; Martin, Nadine; Couchie, Dominique; Préaux, Anne-Marie; Laperche, Yannick; Zafrani, Elie Serge

    2004-01-01

    Stromal cell-derived factor-1 is a chemokine that plays a major role during embryogenesis. Since stromal cell-derived factor-1 and its unique receptor CXCR4 are involved in the differentiation of progenitor cells, we studied the expression of this chemokine and of its receptor in hepatic regeneration from precursor oval cells. Hepatic regeneration was induced by treating rats with 2-acetylaminofluorene, and followed by partial hepatectomy. Oval cell accumulation, which predominated in periportal regions, reached a maximum at days 9 to 14 after hepatectomy and declined thereafter. Oval cells strongly expressed stromal cell-derived factor-1 protein and mRNA. CXCR4 mRNA hepatic level paralleled the number of oval cells and in situ hybridization showed CXCR4 mRNA expression by these cells. Treatment of rats with fucoidan, a sulfated polysaccharide which binds to stromal cell-derived factor-1 and blocks its biological effects, markedly decreased oval cell accumulation in five of the seven treated rats. In conclusion, our data demonstrate an expression of stromal cell-derived factor-1 and of its receptor CXCR4 in oval cells during hepatic regeneration and strongly suggest that stromal cell-derived factor-1 stimulates the proliferation of these precursor cells through an autocrine/paracrine pathway. PMID:15579440

  5. Recovery of liver function in partially hepatectomized rats evaluated by aminopyrine demethylation capacity

    SciTech Connect

    Sendama, I.; de Hemptinne, B.; Lambotte, L.

    1985-07-01

    Aminopyrine demethylation was investigated in rats after a 70% hepatectomy to assess possible parallelism between the recovery of mass and function. Tests were performed by analyzing UCO2 exhalation from 0.1 microCi per 100 gm of body weight of (dimethylamine- UC)aminopyrine given intraperitoneally with incremental doses of unlabeled drug. Early after 70% hepatectomy, Vmax was reduced by 52%. This discordance between mass and function was not due to extrahepatic aminopyrine demethylation, since liver exclusion reduced demethylation of aminopyrine to nearly nil. Whether it results from increased liver blood flow in the remnant liver is less clear. The early increase in Vmax could be related to a hepatotrophic factor of splanchnic origin which increased after partial hepatectomy and decreased after portacaval shunt. After the early period, Vmax, expressed per gram of actual liver weight, returned to control range. Throughout regeneration (4 to 144 hr), no modification was observed in Km nor in cytochrome P-450 concentration. Enzymatic induction with phenobarbital increased the demethylation capacity more than liver weight in intact and regenerating liver. Except for the first hours after partial hepatectomy or after enzymatic induction, the aminopyrine demethylation capacity directly correlated with liver mass and may be useful in evaluating liver regeneration in vivo.

  6. Deletion of Mbtps1 (Pcsk8, S1p, Ski-1) Gene in Osteocytes Stimulates Soleus Muscle Regeneration and Increased Size and Contractile Force with Age.

    PubMed

    Gorski, Jeff P; Huffman, Nichole T; Vallejo, Julian; Brotto, Leticia; Chittur, Sridar V; Breggia, Anne; Stern, Amber; Huang, Jian; Mo, Chenglin; Seidah, Nabil G; Bonewald, Lynda; Brotto, Marco

    2016-02-26

    Conditional deletion of Mbtps1 (cKO) protease in bone osteocytes leads to an age-related increase in mass (12%) and in contractile force (30%) in adult slow twitch soleus muscles (SOL) with no effect on fast twitch extensor digitorum longus muscles. Surprisingly, bone from 10-12-month-old cKO animals was indistinguishable from controls in size, density, and morphology except for a 25% increase in stiffness. cKO SOL exhibited increased expression of Pax7, Myog, Myod1, Notch, and Myh3 and 6-fold more centralized nuclei, characteristics of postnatal regenerating muscle, but only in type I myosin heavy chain-expressing cells. Increased expression of gene pathways mediating EGF receptor signaling, circadian exercise, striated muscle contraction, and lipid and carbohydrate oxidative metabolism were also observed in cKO SOL. This muscle phenotype was not observed in 3-month-old mice. Although Mbtps1 mRNA and protein expression was reduced in cKO bone osteocytes, no differences in Mbtps1 or cre recombinase expression were observed in cKO SOL, explaining this age-related phenotype. Understanding bone-muscle cross-talk may provide a fresh and novel approach to prevention and treatment of age-related muscle loss. PMID:26719336

  7. Preformed class II donor-specific antibodies are associated with an increased risk of early rejection after liver transplantation.

    PubMed

    O'Leary, Jacqueline G; Kaneku, Hugo; Jennings, Linda W; Bañuelos, Nubia; Susskind, Brian M; Terasaki, Paul I; Klintmalm, Göran B

    2013-09-01

    Preformed donor-specific human leukocyte antigen antibodies (DSAs) are considered a contraindication to the transplantation of most solid organs other than the liver. Conflicting data currently exist on the importance of preformed DSAs in rejection and patient survival after liver transplantation (LT). To evaluate preformed DSAs in LT, we retrospectively analyzed prospectively collected samples from all adult recipients of primary LT without another organ from January 1, 2000 to May 31, 2009 with a pre-LT sample available (95.8% of the patients). Fourteen percent of the patients had preformed class I and/or II DSAs with a mean fluorescence intensity (MFI) ≥ 5000. Preformed class I DSAs with an MFI ≥ 5000 remained persistent in only 5% of patients and were not associated with rejection. Preformed class II DSAs with an MFI of 5000 to 10,000 remained persistent in 23% of patients, and this rate increased to 33% for patients whose MFI was ≥10,000 (P < 0.001). Preformed class II DSAs in multivariable Cox proportional hazards modeling were associated with an increased risk of early rejection [hazard ratio (HR) = 1.58; p = 0.004]. In addition, multivariate modeling showed that in comparison with no DSAs (MFI < 1000), preformed class I and/or II DSAs with an MFI ≥ 5000 were independently correlated with the risk of death (HR = 1.51; p = 0.02).

  8. Increased accumulation of 4-hydroxynonenal adducts in female GSTA4/PPAR alpha double knockout mice enhance steatosis and inflammation in a model of pediatric nonalcoholic fatty liver disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hepatocellular injury resulting from increased lipid peroxidation products and oxidative stress is considered a potential mechanism driving the progression of nonalcoholic fatty liver disease (NAFLD) to nonalcoholic steatohepatitsis (NASH). To test the significance of lipid peroxidation and protein...

  9. Inhibition of the Prostaglandin Degrading Enzyme 15-PGDH Potentiates Tissue Regeneration *

    PubMed Central

    Zhang, Yongyou; Desai, Amar; Yang, Sung Yeun; Bae, Ki Beom; Antczak, Monika I.; Fink, Stephen P.; Tiwari, Shruti; Willis, Joseph E.; Williams, Noelle S.; Dawson, Dawn M.; Wald, David; Chen, Wei-Dong; Wang, Zhenghe; Kasturi, Lakshmi; Larusch, Gretchen A.; He, Lucy; Cominelli, Fabio; Di Martino, Luca; Djuric, Zora; Milne, Ginger L.; Chance, Mark; Sanabria, Juan; Dealwis, Chris; Mikkola, Debra; Naidoo, Jacinth; Wei, Shuguang; Tai, Hsin-Hsiung; Gerson, Stanton L.; Ready, Joseph M.; Posner, Bruce; Willson, James K. V.; Markowitz, Sanford D.

    2015-01-01

    Tissue regeneration is a medical challenge faced in injury from disease and during medical treatments such as bone marrow transplantation. Prostaglandin PGE2, which supports expansion of several types of tissue stem cells, is a candidate therapeutic target for promoting tissue regeneration in vivo. Here we show that inhibition of 15-hydroxyprostaglandin dehydrogenase (15-PGDH), a prostaglandin-degrading enzyme, potentiates tissue regeneration in multiple organs in mice. In a chemical screen, we identify a small-molecule inhibitor of 15-PGDH (SW033291) that increases prostaglandin PGE2 levels in bone marrow and other tissues. SW033291 accelerates hematopoietic recovery in mice receiving a bone marrow transplant. SW033291 also promotes tissue regeneration in mouse models of colon and liver injury. Tissues from 15-PGDH knockout mice demonstrate similar increased regenerative capacity. These findings raise the possibility that inhibiting 15-PGDH could be a useful therapeutic strategy in several distinct clinical settings. PMID:26068857

  10. Nanomaterials and bone regeneration

    PubMed Central

    Gong, Tao; Xie, Jing; Liao, Jinfeng; Zhang, Tao; Lin, Shiyu; Lin, Yunfeng

    2015-01-01

    The worldwide incidence of bone disorders and conditions has been increasing. Bone is a nanomaterials composed of organic (mainly collagen) and inorganic (mainly nano-hydroxyapatite) components, with a hierarchical structure ranging from nanoscale to macroscale. In consideration of the serious limitation in traditional therapies, nanomaterials provide some new strategy in bone regeneration. Nanostructured scaffolds provide a closer structural support approximation to native bone architecture for the cells and regulate cell proliferation, differentiation, and migration, which results in the formation of functional tissues. In this article, we focused on reviewing the classification and design of nanostructured materials and nanocarrier materials for bone regeneration, their cell interaction properties, and their application in bone tissue engineering and regeneration. Furthermore, some new challenges about the future research on the application of nanomaterials for bone regeneration are described in the conclusion and perspectives part. PMID:26558141

  11. Adjuvant treatment with tumor-targeting Salmonella typhimurium A1-R reduces recurrence and increases survival after liver metastasis resection in an orthotopic nude mouse model

    PubMed Central

    Murakami, Takashi; Hiroshima, Yukihiko; Zhao, Ming; Zhang, Yong; Chishima, Takashi; Tanaka, Kuniya; Bouvet, Michael; Endo, Itaru; Hoffman, Robert M.

    2015-01-01

    Colon cancer liver metastasis is often the lethal aspect of this disease. Well-isolated metastases are candidates for surgical resection, but recurrence is common. Better adjuvant treatment is therefore needed to reduce or prevent recurrence. In the present study, HT-29 human colon cancer cells expressing red fluorescent protein (RFP) were used to establish liver metastases in nude mice. Mice with a single liver metastasis were randomized into bright-light surgery (BLS) or the combination of BLS and adjuvant treatment with tumor-targeting S. typhimurium A1-R. Residual tumor fluorescence after BLS was clearly visualized at high magnification by fluorescence imaging. Adjuvant treatment with S. typhimurium A1-R was highly effective to increase survival and disease-free survival after BLS of liver metastasis. The results suggest the future clinical potential of adjuvant S. typhimurium A1-R treatment after liver metastasis resection. PMID:26497690

  12. Adjuvant treatment with tumor-targeting Salmonella typhimurium A1-R reduces recurrence and increases survival after liver metastasis resection in an orthotopic nude mouse model.

    PubMed

    Murakami, Takashi; Hiroshima, Yukihiko; Zhao, Ming; Zhang, Yong; Chishima, Takashi; Tanaka, Kuniya; Bouvet, Michael; Endo, Itaru; Hoffman, Robert M

    2015-12-01

    Colon cancer liver metastasis is often the lethal aspect of this disease. Well-isolated metastases are candidates for surgical resection, but recurrence is common. Better adjuvant treatment is therefore needed to reduce or prevent recurrence. In the present study, HT-29 human colon cancer cells expressing red fluorescent protein (RFP) were used to establish liver metastases in nude mice. Mice with a single liver metastasis were randomized into bright-light surgery (BLS) or the combination of BLS and adjuvant treatment with tumor-targeting S. typhimurium A1-R. Residual tumor fluorescence after BLS was clearly visualized at high magnification by fluorescence imaging. Adjuvant treatment with S. typhimurium A1-R was highly effective to increase survival and disease-free survival after BLS of liver metastasis. The results suggest the future clinical potential of adjuvant S. typhimurium A1-R treatment after liver metastasis resection.

  13. Bone marrow cell transplantation is associated with fibrogenic cells apoptosis during hepatic regeneration in cholestatic rats.

    PubMed

    Nunes de Carvalho, Simone; da Cunha Lira, Dalvaci; Costa Cortez, Erika Afonso; de Andrade, Daniela Caldas; Thole, Alessandra Alves; Stumbo, Ana Carolina; de Carvalho, Lais

    2013-04-01

    Liver fibrosis is accompanied by hepatocyte death and proliferation of α-SMA(+) fibrogenic cells (activated hepatic stellate cells and myofibroblasts), which synthesize extracellular matrix components that contribute to disorganization of the hepatic parenchyma and loss of liver function. Therefore, apoptosis of these fibrogenic cells is important to hepatic regeneration. This study aimed to analyze the effect of cell therapy using bone marrow mononuclear cell (BMMNC) transplantation on α-SMA expression and on apoptosis of hepatic cells during liver fibrosis induced by bile duct ligation (BDL). Livers were collected from normal rats, fibrotic rats after 14 and 21 days of BDL, and rats that received BMMNC at 14 days of BDL and were analyzed after 7 days. Apoptosis in fibrogenic cells was analyzed by immunoperoxidase, confocal microscopy, and Western blotting, and liver regeneration was assessed by proliferating cell nuclear antigen staining. Results showed that caspase-3 and proliferating cell nuclear antigen expression were significantly increased in the BMMNC-treated group. Additionally, confocal microscopy analysis showed cells coexpressing α-SMA and caspase-3 in these animals, suggesting fibrogenic cell death. These results suggest a novel role for BMMNC in liver regeneration during fibrotic disease by stimulating fibrogenic cells apoptosis and hepatocyte proliferation, probably through secretion of specific cytokines that modulate the hepatic microenvironment toward an antifibrogenic balance.

  14. Aging and a long-term diabetes mellitus increase expression of 1 α-hydroxylase and vitamin D receptors in the rat liver.

    PubMed

    Vuica, Ana; Ferhatović Hamzić, Lejla; Vukojević, Katarina; Jerić, Milka; Puljak, Livia; Grković, Ivica; Filipović, Natalija

    2015-12-01

    Diabetes mellitus (DM) is a metabolic disorder associated with serious liver complications. As a metabolic chronic disease, DM is very common in the elderly. Recent studies suggest ameliorating effects of vitamin D on metabolic and oxidative stress in the liver tissue in an experimental model of DM. The aim of this study was to investigate the expression of vitamin D receptors (VDRs) and 1α-hydroxylase, the key enzyme for the production of active vitamin D form (calcitriol) in the liver during long-term diabetes mellitus type 1 (DM1) in aging rats. We performed immunohistochemical analysis of liver expression of 1α-hydroxylase and VDRs during aging in long-term streptozotocin-induced DM1. 1α-Hydroxylase was identified in the monocyte/macrophage system of the liver. In addition to the nuclear expression, we also observed the expression of VDR in membranes of lipid droplets within hepatocytes. Aging and long-term DM1 resulted in significant increases in the number of 1α-hydroxylase immunoreactive cells, as well as the percentage of strongly positive VDR hepatocytes. In conclusion, the liver has the capacity for active vitamin D synthesis in its monocyte/macrophage system that is substantially increased in aging and long-term diabetes mellitus. These conditions are also characterized by significant increases in vitamin D receptor expression in hepatocytes. The present study suggests that VDR signaling system could be a potential target in prevention of liver complications caused by diabetes and aging.

  15. Oxidative stress of brain and liver is increased by Wi-Fi (2.45GHz) exposure of rats during pregnancy and the development of newborns.

    PubMed

    Çelik, Ömer; Kahya, Mehmet Cemal; Nazıroğlu, Mustafa

    2016-09-01

    An excessive production of reactive oxygen substances (ROS) and reduced antioxidant defence systems resulting from electromagnetic radiation (EMR) exposure may lead to oxidative brain and liver damage and degradation of membranes during pregnancy and development of rat pups. We aimed to investigate the effects of Wi-Fi-induced EMR on the brain and liver antioxidant redox systems in the rat during pregnancy and development. Sixteen pregnant rats and their 48 newborns were equally divided into control and EMR groups. The EMR groups were exposed to 2.45GHz EMR (1h/day for 5 days/week) from pregnancy to 3 weeks of age. Brain cortex and liver samples were taken from the newborns between the first and third weeks. In the EMR groups, lipid peroxidation levels in the brain and liver were increased following EMR exposure; however, the glutathione peroxidase (GSH-Px) activity, and vitamin A, vitamin E and β-carotene concentrations were decreased in the brain and liver. Glutathione (GSH) and vitamin C concentrations in the brain were also lower in the EMR groups than in the controls; however, their concentrations did not change in the liver. In conclusion, Wi-Fi-induced oxidative stress in the brain and liver of developing rats was the result of reduced GSH-Px, GSH and antioxidant vitamin concentrations. Moreover, the brain seemed to be more sensitive to oxidative injury compared to the liver in the development of newborns.

  16. Age-dependent increase of etheno-DNA-adducts in liver and brain of ROS overproducing OXYS rats

    SciTech Connect

    Nair, Jagadeesan; Sinitsina, Olga; Vasunina, Elena A.; Nevinsky, Georgy A.; Laval, Jacques; Bartsch, Helmut . E-mail: h.bartsch@dkfz.de

    2005-10-21

    Reactive oxygen species (ROS) and lipid peroxidation (LPO) play a role in aging and degenerative diseases. To correlate oxidative stress and LPO-derived DNA damage, we determined etheno-DNA-adducts in liver and brain from ROS overproducing OXYS rats in comparison with age-matched Wistar rats. Liver DNA samples from 3- and 15-month-old OXYS and Wistar rats were analyzed for 1,N {sup 6}-ethenodeoxyadenosine ({epsilon}dA) and 3,N {sup 4}-ethenodeoxycytidine ({epsilon}dC) by immunoaffinity/{sup 32}P-postlabelling. While {epsilon}dA and {epsilon}dC levels were not different in young rats, adduct levels were significantly higher in old OXYS rats when compared to old Wistar or young OXYS rats. Frozen rat brain sections were analyzed for {epsilon}dA by immunostaining of nuclei. Brains from old OXYS rats accumulated {epsilon}dA more frequently than age-matched Wistar rats. Our results demonstrate increased LPO-induced DNA damage in organs of OXYS rats which correlates with their known shorter life-span and elevated frequency of chronic degenerative diseases.

  17. Sugars increase non-heme iron bioavailability in human epithelial intestinal and liver cells.

    PubMed

    Christides, Tatiana; Sharp, Paul

    2013-01-01

    Previous studies have suggested that sugars enhance iron bioavailability, possibly through either chelation or altering the oxidation state of the metal, however, results have been inconclusive. Sugar intake in the last 20 years has increased dramatically, and iron status disorders are significant public health problems worldwide; therefore understanding the nutritional implications of iron-sugar interactions is particularly relevant. In this study we measured the effects of sugars on non-heme iron bioavailability in human intestinal Caco-2 cells and HepG2 hepatoma cells using ferritin formation as a surrogate marker for iron uptake. The effect of sugars on iron oxidation state was examined by measuring ferrous iron formation in different sugar-iron solutions with a ferrozine-based assay. Fructose significantly increased iron-induced ferritin formation in both Caco-2 and HepG2 cells. In addition, high-fructose corn syrup (HFCS-55) increased Caco-2 cell iron-induced ferritin; these effects were negated by the addition of either tannic acid or phytic acid. Fructose combined with FeCl3 increased ferrozine-chelatable ferrous iron levels by approximately 300%. In conclusion, fructose increases iron bioavailability in human intestinal Caco-2 and HepG2 cells. Given the large amount of simple and rapidly digestible sugars in the modern diet their effects on iron bioavailability may have important patho-physiological consequences. Further studies are warranted to characterize these interactions. PMID:24340076

  18. Sugars Increase Non-Heme Iron Bioavailability in Human Epithelial Intestinal and Liver Cells

    PubMed Central

    Christides, Tatiana; Sharp, Paul

    2013-01-01

    Previous studies have suggested that sugars enhance iron bioavailability, possibly through either chelation or altering the oxidation state of the metal, however, results have been inconclusive. Sugar intake in the last 20 years has increased dramatically, and iron status disorders are significant public health problems worldwide; therefore understanding the nutritional implications of iron-sugar interactions is particularly relevant. In this study we measured the effects of sugars on non-heme iron bioavailability in human intestinal Caco-2 cells and HepG2 hepatoma cells using ferritin formation as a surrogate marker for iron uptake. The effect of sugars on iron oxidation state was examined by measuring ferrous iron formation in different sugar-iron solutions with a ferrozine-based assay. Fructose significantly increased iron-induced ferritin formation in both Caco-2 and HepG2 cells. In addition, high-fructose corn syrup (HFCS-55) increased Caco-2 cell iron-induced ferritin; these effects were negated by the addition of either tannic acid or phytic acid. Fructose combined with FeCl3 increased ferrozine-chelatable ferrous iron levels by approximately 300%. In conclusion, fructose increases iron bioavailability in human intestinal Caco-2 and HepG2 cells. Given the large amount of simple and rapidly digestible sugars in the modern diet their effects on iron bioavailability may have important patho-physiological consequences. Further studies are warranted to characterize these interactions. PMID:24340076

  19. Adenovirus 36 attenuates weight loss from exercise but improves glycemic control by increasing mitochondrial activity in the liver.

    PubMed

    Na, Ha-Na; Hong, Young-Mi; Ye, Michael B; Park, Sooho; Kim, In-Beom; Nam, Jae-Hwan

    2014-01-01

    Human adenovirus type 36 (Ad36) as an obesity agent induces adiposity by increasing glucose uptake and promoting chronic inflammation in fat tissues; in contrast, exercise reduces total body fat and inflammation. Our objective was to determine the association between Ad36 and the effects of exercise on inflammation and glycemic control. In the human trials (n = 54), Korean children (aged 12-14 years) exercised for 60 min on three occasions each week for 2 months. We compared the body mass index (BMI) Z-scores before and after exercise. C57BL/6 mice were infected with Ad36 and Ad2 as a control, and these mice exercised for 12 weeks postinfection. After the exercise period, we determined the serum parameters and assessed the presence of inflammation and the mitochondrial function in the organs. Ad36-seropositive children who were subjected to a supervised exercise regimen had high BMI Z-scores whereas Ad36-seronegative children had lower scores. Similarly, Ad36-infected mice were resistant to weight loss and exhibited chronic inflammation of their adipose tissues despite frequent exercise. However, Ad36 combined with exercise reduced the levels of serum glucose, nonesterified fatty acids, total cholesterol, and insulin in virus-infected mice. Interestingly, virus infection increased the mitochondrial function in the liver, as demonstrated by the numbers of mitochondria, cytochrome c oxidase activity, and transcription of key mitochondrial genes. Therefore Ad36 counteracts the weight-loss effect of exercise and maintains the chronic inflammatory state, but glycemic control is improved by exercise synergistically because of increased mitochondrial activity in the liver.

  20. In vivo vitamin C deficiency in guinea pigs increases ascorbate transporters in liver but not kidney and brain.

    PubMed

    Søgaard, Ditte; Lindblad, Maiken M; Paidi, Maya D; Hasselholt, Stine; Lykkesfeldt, Jens; Tveden-Nyborg, Pernille

    2014-07-01

    Moderate vitamin C (vitC) deficiency (plasma concentrations less than 23 μmol/L) affects as much as 10% of adults in the Western World and has been associated with an increased mortality in disease complexes such as cardiovascular disease and the metabolic syndrome. The distribution of vitC within the body is subjected to complex and nonlinear pharmacokinetics and largely depends on the sodium-dependent vitC-specific transporters, sodium-dependent vitamin C transporter 1 (SVCT1) and sodium-dependent vitamin C transporter 2 (SVCT2). Although currently not established, it is likely to expect that a state of deficiency may affect the expression of these transporters to preserve vitC concentrations in specific target tissues. We hypothesized that diet-induced states of vitC deficiency lead to alterations in the messenger RNA (mRNA) and/or protein expression of vitC transporters, thereby regulating vitC tissue distribution. Using guinea pigs as a validated model, this study investigated the effects of a diet-induced vitC deficiency (100 mg vitC/kg feed) or depletion (0 mg vitC/kg feed) on the expression of transporters SVCT1 and SVCT2 in selected tissues and the transport from plasma to cerebrospinal fluid (CSF). In deficient animals, SVCT1 was increased in the liver, whereas a decreased SVCT1 expression but increased SVCT2 mRNA in livers of depleted animals suggests a shift in transporter expression as response to the diet. In CSF, a constant plasma:CSF ratio shows unaltered vitC transport irrespective of dietary regime. The study adds novel information to the complex regulation maintaining vitC homeostasis in vivo during states of deficiency.

  1. Increased susceptibility to liver injury after hemorrhagic shock in rats chronically fed ethanol: role of nuclear factor-kappa B, interleukin-6, and granulocyte colony-stimulating factor.

    PubMed

    Ono, Masafumi; Yu, Bi; Hardison, Edith G; Mastrangelo, Mary-Ann A; Tweardy, David J

    2004-06-01

    Chronic ethanol use preceding severe trauma and hemorrhagic shock (HS) is associated with an increased incidence of multiorgan failure (MOF) and death; however, the molecular basis for this increased susceptibility is unknown. We previously demonstrated that production of interleukin-6 (IL-6) and granulocyte colony-stimulating factor (G-CSF), mediated by nuclear factor-kappa B (NF-kappa B), each make essential contributions to organ injury and inflammation in a rodent model of controlled HS, and we proposed in this study to examine the hypothesis that the increased susceptibility to MOF after shock/trauma in the setting of chronic ethanol use is due to an exaggerated activation of NF-kappa B and production of these proinflammatory cytokines. We observed increased HS-induced liver injury 4 h after resuscitation in rats fed the ethanol-containing Lieber-DeCarli liquid diet for 8 weeks compared with rats fed the control liquid diet (3-fold increase in serum alanine aminotransferase [ALT], P = 0.008, and 2-fold increase in focal liver necrosis, P = 0.005). The increased liver injury in the ethanol-fed HS rats was accompanied by a 70% increase in liver NF-kappa B activation (P < 0.05), a 3- to 5-fold increase in hepatocyte and Kupffer cell production of IL-6 and G-CSF (P < 0.05 for each), and a 2-fold increase in neutrophil infiltration (P < 0.005) compared with the control diet-fed HS rats. Thus, increased susceptibility to HS-induced liver injury in the setting of chronic ethanol use may be mediated, at least in part, by increased NF-kappa B activation resulting in increased local production of IL-6 and G-CSF and increased infiltration of neutrophils, which can damage liver cells directly and contribute to impaired sinusoidal blood flow.

  2. Cytochrome c release from rat liver mitochondria is compromised by increased saturated cardiolipin species induced by sucrose feeding.

    PubMed

    Ruiz-Ramírez, Angélica; Barrios-Maya, Miguel-Angel; López-Acosta, Ocarol; Molina-Ortiz, Dora; El-Hafidi, Mohammed

    2015-11-01

    Cytochrome c release from mitochondria has been described to be related to reactive oxygen species (ROS) generation. With ROS generation being increased in fatty liver from sucrose-fed (SF) rats, we hypothesized that cytochrome c release might be positively associated with H2O2 generation from SF mitochondria. Surprisingly, cytochrome c release from mitochondria of SF liver was found to be significantly lower compared with control (C) mitochondria oxidizing pyruvate/malate or succinate. Exposure of mitochondria to exogenous superoxide radical generated by the xanthine/xanthine oxidase system elicits a dose-response cytochrome c release in both control and SF mitochondria, but cytochrome c release remains lower in SF mitochondria compared with C mitochondria. Furthermore, the addition of ebselen, PEG-catalase, or catalase, a H2O2 scavenger, significantly reduces cytochrome c release from C and SF mitochondria. Our results suggest that both intra- and extramitochondrial H2O2 are involved in cytochrome c release, but the persisting difference between C and SF levels can be attributed to the differences in cardiolipin compositions. Indeed, the ratio of palmitic acid-rich cardiolipin species was found to be increased in lipid membrane from SF mitochondria compared with C mitochondria, whereas that of linoleic acid-rich cardiolipin species was found decreased. In addition, the content of tafazzin, a protein responsible for cardiolipin remodeling, was decreased in SF mitochondria. Therefore, we conclude that the changes observed in the composition of cardiolipin molecular species in SF mitochondria may be involved in cytochrome c interaction with mitochondrial inner membrane lipid and in its reduced release from SF mitochondria.

  3. Increased expression of 78 kD glucose-regulated protein promotes cardiomyocyte apoptosis in a rat model of liver cirrhosis

    PubMed Central

    Zhang, Lili; Zhang, Huiying; Lv, Minli; Jia, Jiantao; Fan, Yimin; Tian, Xiaoxia; Li, Xujiong; Li, Baohong; Ji, Jingquan; Wang, Limin; Zhao, Zhongfu; Han, Dewu; Ji, Cheng

    2015-01-01

    Aims: This study was to investigate the role and underlying mechanism of 78 kD glucose-regulated protein (GRP78) in cardiomyocyte apoptosis in a rat model of liver cirrhosis. Methods: A rat model of liver cirrhosis was established with multiple pathogenic factors. A total of 42 male SD rats were randomly divided into the liver cirrhosis group and control group. Cardiac structure analysis was performed to assess alterations in cardiac structure. Cardiomyocytes apoptosis was detected by TdT-mediated dUTP nick end labeling method. Expression of GRP78, CCAAT/enhancer-binding protein homologous protein (CHOP), caspase-12, nuclear factor kappa-light-chain-enhancer of activated B cells p65 subunit (NF-κB p65) and B cell lymphoma-2 (Bcl-2) was detected by immunohistochemical staining. Results: The ratios of left ventricular wall thickness to heart weight and heart weight to body weight were significantly increased with the progression of liver cirrhosis (P < 0.05). Apoptosis index of cardiomyocytes was significantly increased with the progression of liver cirrhosis (P < 0.05). The expression levels of GRP78, CHOP and caspase-12 were significantly increased in the progression of liver cirrhosis (P < 0.05). The expression levels of NF-κB p65 and Bcl-2 were highest in the 4-wk liver cirrhosis, and they were decreased in the 6-wk and 8-wk in the progression of liver cirrhosis. GRP78 expression levels were positively correlated with apoptosis index, CHOP and caspase-12 expression levels (P < 0.05). CHOP expression levels were negatively correlated with NF-κB p65 and Bcl-2 expression levels (P < 0.05). Conclusion: Increased expression of GRP78 promotes cardiomyocyte apoptosis in rats with cirrhotic cardiomyopathy. PMID:26464674

  4. Dynamics of zebrafish fin regeneration