The mechanistic target of rapamycin (mTOR) signaling pathway regulates many metabolic and physiological processes in different organs or tissues. Dysregulation of mTOR signaling has been implicated in many human diseases including obesity, diabetes, cancer, fatty liver diseases, and neuronal disorders. Here we review recent progress in understanding how mTORC1 (mTOR complex 1) signaling regulates lipid metabolism in the liver.
Animals ; Humans ; Lipid Metabolism ; Lipogenesis ; Liver ; cytology ; metabolism ; pathology ; Mechanistic Target of Rapamycin Complex 1 ; metabolism ; Signal Transduction

BACKGROUND/AIMS: To assess the usefulness of magnetization-tagged magnetic resonance imaging (MRI) in quantifying cardiac-induced liver motion and deformation in order to predict liver fibrosis. METHODS: This retrospective study included 85 patients who underwent liver MRI including magnetization-tagged sequences from April 2010 to August 2010. Tagged images were acquired in three coronal and three sagittal planes encompassing both the liver and heart. A Gabor filter bank was used to measure the maximum value of displacement (MaxDisp) and the maximum and minimum values of principal strains (MaxP1 and MinP2, respectively). Patients were divided into three groups (no fibrosis, mild-to-moderate fibrosis, and significant fibrosis) based on their aspartate-aminotransferase-to-platelet ratio index (APRI) score. Group comparisons were made using ANOVA tests. RESULTS: The patients were divided into three groups according to APRI scores: no fibrosis (≤0.5; n=41), moderate fibrosis (0.5-1.5; n=23), and significant fibrosis (>1.5; n=21). The values of MaxDisp were 2.9±0.9 (mean±SD), 2.3±0.7, and 2.1±0.6 in the no fibrosis, moderate fibrosis, and significant fibrosis groups, respectively (P<0.001); the corresponding values of MaxP1 were 0.05±0.2, 0.04±0.02, and 0.03±0.01, respectively (P=0.002), while those of MinP2 were -0.07±0.02, -0.05±0.02, and -0.04±0.01, respectively (P<0.001). CONCLUSIONS: Tagged MRI to quantify cardiac-induced liver motion can be easily incorporated in routine liver MRI and may represent a helpful complementary tool in the diagnosis of early liver fibrosis.
Aged ; Aspartate Aminotransferases/analysis ; Blood Platelets/cytology ; Humans ; Liver Cirrhosis/*diagnostic imaging/metabolism/pathology ; *Magnetic Resonance Imaging ; Male ; Middle Aged ; Retrospective Studies ; Severity of Illness Index

BACKGROUND/AIMS: Chronic liver disease leads to liver fibrosis, and although the liver does have a certain regenerative capacity, this disease is associated with dysfunction of the liver vessels. C-reactive protein (CRP) is produced in the liver and circulated from there for metabolism. CRP was recently shown to inhibit angiogenesis by inducing endothelial cell dysfunction. The objective of this study was to determine the effect of CRP levels on angiogenesis in a rat model of liver dysfunction induced by bile duct ligation (BDL). METHODS: The diameter of the hepatic vein was analyzed in rat liver tissues using hematoxylin and eosin (H&E) staining. The expression levels of angiogenic factors, albumin, and CRP were analyzed by real-time PCR and Western blotting. A tube formation assay was performed to confirm the effect of CRP on angiogenesis in human umbilical vein endothelial cells (HUVECs) treated with lithocholic acid (LCA) and siRNA-CRP. RESULTS: The diameter of the hepatic portal vein increased significantly with the progression of cirrhosis. The expression levels of angiogenic factors were increased in the cirrhotic liver. In contrast, the expression levels of albumin and CRP were significantly lower in the liver tissue obtained from the BDL rat model than in the normal liver. The CRP level was correlated with the expression of albumin in hepatocytes treated with LCA and siRNA-CRP. Tube formation was significantly decreased in HUVECs when they were treated with LCA or a combination of LCA and siRNA-CRP. CONCLUSION: CRP seems to be involved in the abnormal formation of vessels in hepatic disease, and so it could be a useful diagnostic marker for hepatic disease.
Angiogenic Proteins/genetics/metabolism ; Animals ; Bile Ducts/surgery ; C-Reactive Protein/*analysis/genetics/metabolism ; Cells, Cultured ; Disease Models, Animal ; Hepatic Veins/abnormalities ; Hepatocytes/cytology/metabolism ; Human Umbilical Vein Endothelial Cells ; Humans ; Lithocholic Acid/pharmacology ; Liver/metabolism/pathology ; Liver Cirrhosis/etiology ; Liver Diseases/metabolism/*pathology ; Male ; Microscopy, Fluorescence ; Mitochondria/drug effects/metabolism ; RNA Interference ; RNA, Small Interfering/metabolism ; Rats ; Rats, Sprague-Dawley ; Real-Time Polymerase Chain Reaction ; Serum Albumin/genetics/metabolism

Vertical sleeve gastrectomy (VSG) is becoming more and more popular among the world. Despite its dramatic efficacy, however, the mechanism of VSG remains largely undetermined. This study aimed to test interferon (IFN)-γ secretion n of mesenteric lymph nodes in obese mice (ob/ob mice), a model of VSG, and its relationship with farnesoid X receptor (FXR) expression in the liver and small intestine, and to investigate the weight loss mechanism of VSG. The wild type (WT) mice and ob/ob mice were divided into four groups: A (WT+Sham), B (WT+VSG), C (ob/ob+Sham), and D (ob/ob+VSG). Body weight values were monitored. The IFN-γ expression in mesenteric lymph nodes of ob/ob mice pre- and post-operation was detected by flow cytometry (FCM). The FXR expression in the liver and small intestine was detected by Western blotting. The mouse AML-12 liver cells were stimulated with IFN-γ at different concentrations in vitro. The changes of FXR expression were also examined. The results showed that the body weight of ob/ob mice was significantly declined from (40.6±2.7) g to (27.5±3.8) g on the 30th day after VSG (P<0.05). At the same time, VSG induced a higher level secretion of IFN-γ in mesenteric lymph nodes of ob/ob mice than that pre-operation (P<0.05). The FXR expression levels in the liver and small intestine after VSG were respectively 0.97±0.07 and 0.84±0.07 fold of GAPDH, which were significantly higher than pre-operative levels of 0.50±0.06 and 0.48±0.06 respectively (P<0.05). After the stimulation of AML-12 liver cells in vitro by different concentrations of IFN-γ (0, 10, 25, 50, 100, and 200 ng/mL), the relative FXR expression levels were 0.22±0.04, 0.31±0.04, 0.39±0.05, 0.38±0.05, 0.56±0.06, and 0.35±0.05, respectively, suggesting IFN-γ could distinctly promote the FXR expression in a dose-dependent manner in comparison to those cells without IFN-γ stimulation (P<0.05). It was concluded that VSG induces a weight loss in ob/ob mice by increasing IFN-γ secretion of mesenteric lymph nodes, which then increases the FXR expression of the liver and small intestine.
Animals ; Body Weight ; Cell Line ; Gastrectomy ; methods ; Gene Expression ; Hepatocytes ; cytology ; drug effects ; metabolism ; Interferon-gamma ; biosynthesis ; pharmacology ; secretion ; Intestine, Small ; drug effects ; metabolism ; Liver ; drug effects ; metabolism ; Lymph Nodes ; drug effects ; metabolism ; Mesentery ; drug effects ; metabolism ; Mice ; Mice, Obese ; Obesity ; metabolism ; pathology ; surgery ; Receptors, Cytoplasmic and Nuclear ; agonists ; genetics ; metabolism ; Weight Loss

OBJECTIVETo study the clinicopathologic features of combined hepatocellular-cholangiocarcinoma (cholangiolocellular type, CLC type) with stem cell features and its relationship to hepatic progenitor cells (HPCs).

METHODSClinical and histologic features of 26 cases of combined hepatocellular-cholangiocarcinoma (CLC type) were reviewed. Histochemistry was performed to confirm the type of mucin and immunohistochemical study was carried out for hepatocytic markers (Hep Par-1 and AFP) and biliary/HPCs markers (CK7, CK9, EMA, EpCAM, NCAM, CKIT).

RESULTSThe age of patients ranged from 51 to 82 years (mean 64 years). All 26 cases contained CLC and hepatocellular carcinoma components. CLC area was composed of mixtures of small monotonous glands with abundant fibrous stroma and lymphocytic infiltrate. Tumor cells were cuboidal, smaller in size than normal hepatocytes, with basophilic cytoplasm and round nuclei. All cases, especially at the tumor boundary, showed HCC-like trabecular areas characterized by mildly atypical tumor cells with abundant eosinophilic cytoplasm and little stroma. Out of 26 cases, 21 showed definite glandular formation with mucin production, representing intrahepatic cholangiocarcinoma areas. The three distinct areas showed transitional zones merging with each other. The surrounding liver tissue showed cirrhosis and chronic hepatitis with varying degrees of fibrosis and periportal ductular reaction. Immunohistochemistry showed that biliary/HPC markers (CK7, CK9, EMA, EpCAM, NCAM and CKIT) were strongly positive in CLC area in almost all cases, similar to the staining pattern of ductular reaction. In HCC-like areas, CK7 and CK19 were positive in all cases and the expression rates of EMA, EpCAM, NCAM, CKIT, AFP, Hep Par-1 were 80.8% (21/26), 88.5% (23/26), 84.6% (22/26), 88.5% (23/26), 46.2% (12/26) and 53.8% (14/26) respectively, similar to the staining pattern of intermediate hepatocytes. In ICC areas, CK7, CK9, EMA and EpCAM were positive in all cases without the expression of NCAM and CKIT.

CONCLUSIONThe clinicopathologic findings and immunohistochemical results in this study highly suggest a hepatic progenitor cell origin of combined hepatocellular-cholangiocarcinoma (CLC type).

Bile Duct Neoplasms ; pathology ; Biomarkers ; metabolism ; Carcinoma, Hepatocellular ; pathology ; Cholangiocarcinoma ; pathology ; Hepatocytes ; cytology ; Humans ; Immunohistochemistry ; Liver Cirrhosis ; pathology ; Liver Neoplasms ; pathology ; Mucins ; metabolism ; Stem Cells ; cytology

No abstract available.
Antibodies, Monoclonal, Murine-Derived/therapeutic use ; Antineoplastic Combined Chemotherapy Protocols/therapeutic use ; B-Cell-Specific Activator Protein/metabolism ; Bone Marrow/metabolism/*pathology ; Cyclophosphamide/therapeutic use ; Doxorubicin/therapeutic use ; Endoscopy, Digestive System ; Female ; Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor ; Genetic Loci ; Humans ; Liver/metabolism/pathology ; Lymphocytes/cytology/immunology ; Lymphoma, Large B-Cell, Diffuse/complications/*diagnosis/drug therapy ; Lymphoma, T-Cell, Peripheral/complications/*diagnosis/drug therapy ; Middle Aged ; Prednisone/therapeutic use ; Receptors, Antigen, T-Cell, gamma-delta/genetics ; Tomography, X-Ray Computed ; Vincristine/therapeutic use

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.
Cytokines/metabolism ; Embolization, Therapeutic ; Hepatectomy ; Humans ; Liver/*metabolism/pathology ; Liver Failure/therapy ; *Liver Regeneration ; Liver Transplantation ; Stem Cell Transplantation ; Stem Cells/cytology

To study the potential molecular mechanism of tumor angiogenesis in its microenvironment, we investigated the effects of HepG2 conditioned medium on the proliferation of vascular endothelial cell and vascular angiogenesis in our laboratory. Human umbilical vein endothelial EA. hy926 cells were co-cultured with HepG2 conditioned medium in vitro. The proliferation and the tubulogenesis of EA. hy926 cells were detected by teramethylazo salt azole (MTT) and tube formation assay, respectively. The results showed that the survival rate of the EA. hy926 cells was significantly increased under the co-culture condition. HepG2 conditioned medium also enhanced the angiogenesis ability of EA. hy926 cells. In addition, the expressions of intracellular VEGF and extracellular VEGFR (Flk-1) were regulated upward in a time-dependent manner. In conclusion, the proliferation of vascular endothelial cells and Vascula angiogenesis were improved under the condition of indirect co-culture.
Carcinoma, Hepatocellular ; pathology ; Cell Proliferation ; Coculture Techniques ; Culture Media, Conditioned ; Endothelial Cells ; cytology ; Hep G2 Cells ; Human Umbilical Vein Endothelial Cells ; Humans ; Liver Neoplasms ; pathology ; Neovascularization, Pathologic ; Tumor Microenvironment ; Vascular Endothelial Growth Factor A ; metabolism ; Vascular Endothelial Growth Factor Receptor-2 ; metabolism

OBJECTIVETo explore the effect of colon cancer cell-derived interleukin-1α on the migration and proliferation of human umbilical vein endothelial cells as well as the role of IL-1α and IL-1ra in the angiogenesis process.

METHODSWestern blot was used to detect the expression of IL-1α and IL-1R1 protein in the colon cancer cell lines with different liver metastatic potential. We also examined how IL-1α and IL-1ra influence the proliferation and migration of umbilical vascular endothelial cells assessed by PreMix WST-1 assay and migration assay, respectively. Double layer culture technique was used to detect the effect of IL-1α on the proliferation and migration of vascular endothelial cells and the effect of IL-1ra on the vascular endothelial cells.

RESULTSWestern blot analysis showed that IL-1α protein was only detected in highly metastatic colon cancer HT-29 and WiDr cells, but not in the lowly metastatic CaCo-2 and CoLo320 cells.Migration assay showed that there were significant differences in the number of penetrated cells between the control (17.9±3.6) and 1 ng/ml rIL-1α group (23.2±4.2), 10 ng/ml rIL-1α group (31.7±4.5), and 100 ng/ml rIL-1α group (38.6±4.9), showing that it was positively correlated with the increasing concentration of rIL-1α (P<0.01 for all). The proliferation assay showed that the absorbance values were 1.37±0.18 in the control group, and 1.79±0.14 in the 1 ng/ml rIL-1α group, 2.14±0.17 in the 10 ng/ml rIL-1α group, and 2.21±0.23 in the 100 ng/ml rIL-1α group, showing a positive correlation with the increasing concentration of rIL-1α(P<0.01 for all). IL-1ra significantly inhibited the proliferation and migration of vascular endothelial cells (P<0.01). The levels of VEGF protein were (1.697±0.072) ng/ml, (3.507±0.064)ng/ml and (4.139±0.039)ng/ml in the control, HUVECs+ IL-1α and HUVECs+ HT-29 co-culture system groups, respectively, showing a significant difference between the control and HUVECs+ 10 pg/ml rIL-1α groups and between the control and HUVECs+ HT-29 groups (P<0.01 for both).

CONCLUSIONSOur findings indicate that colon cancer cell-derived IL-1α plays an important role in the liver metastasis of colon cancer through increased VEGF level of the colon cancer cells and enhanced vascular endothelial cells proliferation, migration and angiogenesis, while IL-1ra can suppress the effect of IL-1α and inhibit the angiogenesis in colon cancer.

Blotting, Western ; Caco-2 Cells ; Cell Line, Tumor ; Cell Movement ; physiology ; Cell Proliferation ; physiology ; Coculture Techniques ; Colonic Neoplasms ; blood supply ; metabolism ; pathology ; Human Umbilical Vein Endothelial Cells ; cytology ; Humans ; Interleukin 1 Receptor Antagonist Protein ; metabolism ; physiology ; Interleukin-1alpha ; metabolism ; physiology ; Liver Neoplasms ; secondary ; Neovascularization, Pathologic ; etiology

The technique of stem cells or hepatocytes transplantation has recently improved in order to bridge the time before whole-organ liver transplantation. In the present study, unfractionated bone marrow stem cells (BMSCs) were harvested from the tibial and femoral marrow compartments of male mice, which were cultured in Dulbecco's modified Eagle's medium (DMEM) with and without hepatocyte growth factor (HGF), and then transplanted into Schistosoma mansoni-infected female mice on their 8th week post-infection. Mice were sacrificed monthly until the third month of bone marrow transplantation, serum was collected, and albumin concentration, ALT, AST, and alkaline phosphatase (ALP) activities were assayed. On the other hand, immunohistopathological and immunohistochemical changes of granuloma size and number, collagen content, and cells expressing OV-6 were detected for identification of liver fibrosis. BMSCs were shown to differentiate into hepatocyte-like cells. Serum ALT, AST, and ALP were markedly reduced in the group of mice treated with BMSCs than in the untreated control group. Also, granuloma showed a marked decrease in size and number as compared to the BMSCs untreated group. Collagen content showed marked decrease after the third month of treatment with BMSCs. On the other hand, the expression of OV-6 increased detecting the presence of newly formed hepatocytes after BMSCs treatment. BMSCs with or without HGF infusion significantly enhanced hepatic regeneration in S. mansoni-induced fibrotic liver model and have pathologic and immunohistopathologic therapeutic effects. Also, this new therapeutic trend could generate new hepatocytes to improve the overall liver functions.
Alanine Transaminase/blood ; Alkaline Phosphatase/blood ; Animals ; Antigens, Differentiation/biosynthesis ; Aspartate Aminotransferases/blood ; Bone Marrow Cells/cytology ; *Bone Marrow Transplantation ; Cell Differentiation ; Cell- and Tissue-Based Therapy ; Cells, Cultured ; Collagen/metabolism ; Female ; Granuloma/parasitology/pathology ; Hepatocyte Growth Factor/pharmacology ; Hepatocytes/*cytology ; Liver/parasitology/pathology ; Liver Cirrhosis/parasitology/pathology/*therapy ; Male ; Mice ; Mice, Inbred BALB C ; Schistosoma mansoni/pathogenicity ; Schistosomiasis mansoni/mortality/*therapy ; *Stem Cell Transplantation ; Stem Cells/cytology