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Isao Sakaida

Publications and source records attributed to Isao Sakaida.

At least 19 recordsLinked to original sources
PubMed2007

Relationship between molecular markers and endoscopic findings in laterally spreading tumors.

BACKGROUND AND AIM: Characteristic clinicopathological features of laterally spreading tumors (LSTs) have been reported by endoscopists; however, only a few studies have been conducted on the biological features. These studies were not fully associated with the endoscopic findings of LSTs. The aim of this study was to estimate the biological features of each type of endoscopic finding of LST using two molecular markers, matrix metalloproteinase-7 (MMP-7) and beta-catenin. METHODS: Expression of the molecular markers and the endoscopic findings were compared in 22 LSTs and 14 subpedunculated polyps. MMP-7 and beta-catenin were immunostained. Three types of representative endoscopic findings of LST were defined as segments in LSTs. They were 15 granular segments, seven large nodular segments, and seven flat segments that corresponded to the area composed of aggregates of similar size granules, large nodules of diameter more than 10 mm, and a flat surface with no granule, respectively. RESULTS: Expression of MMP-7 and coexpression of MMP-7 and beta-catenin were higher in large nodular segments than in granular segments (P < 0.0167). Among the three types of segments, flat segments showed the highest expression densities of beta-catenin accumulated in the nucleus. Large nodular segments and subpedunculated polyps showed similar expression patterns for the molecular markers. CONCLUSIONS: This study provides new and important information on the relationship between the molecular markers and endoscopic findings of LSTs.

Aged↗
PubMed2006

Administration of fibroblast growth factor 2 in combination with bone marrow transplantation synergistically improves carbon-tetrachloride-induced liver fibrosis in mice.

We previously reported that fibroblast growth factor 2 (FGF2) facilitated the differentiation of transplanted bone marrow cells (BMCs) into hepatocytes. Our earlier study also demonstrated that administration of FGF2 in combination with bone marrow transplantation (BMT) synergistically activated tumor necrosis factor-alpha signaling and significantly improved liver function and prognosis more than BMT alone. However, the way that it affected the extracellular matrix remained unclear. Here, we investigated the effect of FGF2 treatment together with BMT on liver fibrosis in mice treated with carbon tetrachloride (CCl(4)). Transplantation of BMCs and concurrent treatment with FGF2 caused a statistically significant reduction in CCl(4)-induced liver fibrosis that was accompanied by strong expression of matrix metalloproteinase 9 as compared with FGF2-only treatment or BMT alone. Moreover, in this process, the proliferation of bone-marrow-derived cells was accelerated without causing apoptosis. Thus, the administration of FGF2 in combination with BMT synergistically improves CCl(4)-induced liver fibrosis in mice. This treatment has the potential of being an effective therapy for patients with liver cirrhosis.

Animals↗
PubMed2006

Improved liver function in patients with liver cirrhosis after autologous bone marrow cell infusion therapy.

We here report nine liver cirrhosis (LC) patients that underwent autologous bone marrow cell infusion (ABMI) from the peripheral vein. Subjects were patients with LC with total bilirubin of less than 3.0 mg/dl, platelet count of more than 5 (10(10)/l), and no viable hepatocellular carcinoma on diagnostic imaging. Autologous bone marrow (BM; 400 ml) was isolated from the ilium under general anesthesia. Mononuclear cells (MNCs) were separated by cell washing and were infused via the peripheral vein. MNC characteristics were confirmed by fluorescence-activated cell sorting analysis (CD34, CD45, and c-kit). After ABMI therapy, liver function was monitored by blood examination for 24 weeks. From 400 ml of BM, we obtained 7.81 +/- 0.98 x 10(9) MNCs. After washing, 5.20 +/- 0.63 x 10(9) MNCs were infused into patients with LC. Significant improvements in serum albumin levels and total protein were observed at 24 weeks after ABMI therapy (p < .05). Significantly improved Child-Pugh scores were seen at 4 and 24 weeks (p < .05). alpha-Fetoprotein and proliferating cell nuclear antigen (PCNA) expression in liver biopsy tissue was significantly elevated after ABMI therapy (p < .05). No major adverse effects were noted. In conclusion, ABMI therapy should be considered as a novel treatment for patients with decompensated LC.

Aged↗
PubMed2006

Increased expression and phosphorylation of liver glutamine synthetase in well-differentiated hepatocellular carcinoma tissues from patients infected with hepatitis C virus.

Hepatocellular carcinoma (HCC) is one of the most common fatal cancers, and chronic infection with hepatitis C virus (HCV) is thought to be one of the main causes in Japan. To identify diagnostic or therapeutic biomarkers for HCC associated with HCV (HCV-HCC), we tried to elucidate the factors related to the products from cancerous tissues of HCV-infected patients. From proteomic differential display analysis of liver tissue samples from HCV-HCC cancerous tissues and corresponding non-cancerous tissues from patients, three protein spots of the same molecular mass (42 kDa), whose expression increased in well-differentiated cancerous tissues, were detected. Although their pI were different, they were identified as glutamine synthetase (GS) by PMF with MALDI-TOF MS and by Western blotting using anti-GS specific mAb. Immunohistochemical analysis showed that tumor tissue consists of two parts, GS-positive cell and GS-negative cell regions, suggesting that GS-producing cells grew in the tumor tissue as a nodule in nodules. The tryptic peptides of the most acidic GS isoform lost the signal of 899.5 Da, corresponding a peptide of SASIRIPR, and gained a signal of 1059.5 Da, which was submitted to PSD analysis. PSD analysis showed the neutral loss by elimination of two phosphate groups, supposed to be on serine residues of the 899.5-Da peptide, from serine 320 to arginine 327 in GS. PMF followed by PSD analysis is thought to be useful for the determination of phosphorylation sites of proteins showing molecular heterogeneity.

Amino Acid Sequence↗
PubMed2006

Proteomic analysis of serum marker proteins in recipient mice with liver cirrhosis after bone marrow cell transplantation.

We previously found that transplantation with bone marrow cells (BMCs) improves liver function and liver fibrosis in cirrhotic mice. In the presence of liver damage induced by carbon tetrachloride (CCl4), transplanted BMC migrated into the peri-portal region and trans-differentiated into hepatocytes that produce albumin. Thus under these conditions, BMC transplantation induces liver regeneration. Detecting serum marker proteins is important to monitor the recovery of liver function of cirrhotic mice after BMC transplantation. We therefore initially resolved proteins extracted from serum samples at 48 h after BMC transplantation by 2-DE and compared spot intensity between control and BMC groups of mice. Six protein spots increased in the BMC group compared with the control group. MS revealed that these spots comprised apolipoprotein A1 (apoA1), apolipoprotein C3 (apoC3), vitamin D-binding protein, alpha-1-antitrypsin and proteasome subunit alpha type 1. We subsequently confirmed the levels of apoA1 in serum and liver samples by immunoblotting. ApoA1 increased at early stage (48 h and 1 wk) after BMC transplantation in this mouse model of liver cirrhosis. The early elevation of apoA1 might be useful to predict liver regeneration in cirrhotic mice after BMC transplantation.

Animals↗
PubMed2006

Proteomic analysis of autoantibodies in patients with hepatocellular carcinoma.

To detect autoantibodies that could be diagnostic markers for hepatocellular carcinoma (HCC), we analyzed serum autoantibodies comprehensively that showed immunoreactivity to proteins in tumor tissue obtained from patients with HCC. Fifteen paired samples of HCC tissue and corresponding nontumorous liver tissue as well as five normal liver tissue samples were used in the study. A combination of proteomics and SEREX (serologic analysis of recombinant cDNA expression libraries) technique was used. Tissue proteins were separated by 2-DE, transferred onto PVDF membranes, and immunoblotted with autologous sera. By comparing each immunoblot pattern, we identified four immunoreactive spots with stronger staining intensity in tumorous tissues than in corresponding nontumorous tissues and in normal liver tissues. Matched proteins on 2-DE gels were identified by LC-MS/MS. These immunoreactive proteins were heat shock 70 kDa protein 1 (HSP70), glyceraldehyde 3-phosphate dehydrogenase, peroxiredoxin, and manganese superoxide dismutase (Mn-SOD). In HCC sera, occurrences of autoantibodies against these proteins were 7/15 (46.7%), 5/15 (33.3%), 5/15 (33.3%), and 6/15 (40.0%), respectively, whereas 2/20 (10.0%), 7/20 (35.0%), 0/20 (0.0%), and 2/20 (10.0%) were in control sera. Immunoblot analysis using commercially available purified proteins was performed to confirm the specificity of autoantibodies. By statistical analysis, autoantibodies against HSP70, peroxiredoxin, and Mn-SOD showed significantly high-frequency immunoreaction in HCC sera. The three antibodies were considered patient-specific antibodies in HCC and may be candidate diagnostic biomarkers for HCC.

Adult↗
PubMed2006

Hepatic iron overload induces hepatocellular carcinoma in transgenic mice expressing the hepatitis C virus polyprotein.

BACKGROUND & AIMS: Despite the evidence of hepatic iron overload in patients with chronic hepatitis C, it remains unknown if iron overload is related to hepatocarcinogenesis in this condition. The aim of this study was to determine whether iron overload contributes to development of hepatocellular carcinoma (HCC) in transgenic mice expressing the hepatitis C virus (HCV) polyprotein. METHODS: Male C57BL/6 transgenic mice expressing the HCV polyprotein and nontransgenic littermates were fed an excess-iron diet or control diet. Mice in each group were assessed for altered liver morphology and function and the development of liver tumors. RESULTS: Hepatic iron concentrations in mice fed the excess-iron diet were comparable to those of patients with chronic hepatitis C. There was no inflammation in transgenic and nontransgenic livers. Compared with mice in 3 other groups, transgenic mice fed the excess-iron diet showed marked hepatic steatosis including the centrilobular microvesicular type, ultrastructural alterations of the mitochondria and decreased degradation activity of fatty acid at 6 months, and greater hepatic content of lipid peroxidation products and 8-hydroxy-2'-deoxyguanosine at 12 months after initiation of feeding. The number of proliferating hepatocytes was significantly increased in mice fed the excess-iron diet but was not different between transgenic and nontransgenic mice. Hepatic tumors including HCC developed in 5 of 11 (45%) transgenic mice fed the excess-iron diet but not in mice in other groups at 12 months after initiation of feeding. CONCLUSIONS: Iron overload induces mitochondrial injury and increases the risk of HCC development in transgenic mice expressing the HCV polyprotein.

Animals↗
PubMed2006

Clinical significance of measuring blood coagulation factor XIIIA regularly and continuously in patients with Crohn's disease.

BACKGROUND: The aim of the present paper was to determine the mechanism by which the level of coagulation factor XIIIA declines during the active phase of Crohn's disease. METHODS: The relationship between the activity of Crohn's disease and factor XIIIA was observed in 31 patients with Crohn's disease prospectively. The relationship between factor XIIIA and thrombin-antithrombin III complex (TAT), factor XIIIA expressed on the surface of peripheral monocytes, was also evaluated. RESULTS: During the first year, there were 11 patients with Crohn's disease in the active phase and 20 patients who remained in remission. The average of the lowest level of factor XIIIA among the patients in the active phase was 60.1%. The average of the lowest level of factor XIIIA in patients who remained in remission was 78.1% (P = 0.049). Among the 20 patients who remained in remission for 1 year, eight patients had factor XIIIA levels below 70%. Six of them required surgical enterectomies, on average 2 years and 1 month later. However, none of the 12 patients who remained in remission for 1 year and who never had factor XIIIA levels <70% had a surgical enterectomy during follow up of 4 years and 6 months (P = 0.002). The decline of factor XIIIA was not due to increased consumption secondary to blood coagulation (TAT), nor was it due to a decline in the function of monocytes that produce factor XIIIA. CONCLUSION: Factor XIIIA declines during the active phase of Crohn's disease because it might be consumed in the repair of injured tissue.

Adult↗
PubMed2006

Protein level of apolipoprotein E increased in human hepatocellular carcinoma.

Many reports suggest that hepatic steatosis leads to hepatocellular carcinoma (HCC), including hepatitis C virus or non-alcoholic steatohepatitis. Proteomic study of tumor tissues from HCC patients, focusing on apolipoprotein (apo) of apoA1, apoB100 and apoE, was performed by immunoblotting. Although the significant changes of apoA1 or apoB100 could not be shown statistically, the immunoblotting showed the increase in protein level of apoE in the tumor tissues of 88% of patients without increase of apoE gene expression and serum level. These results suggest the accumulation of apoE by impaired secretion. Moreover, immunoblot analysis on two-dimensional electrophoresis showed a strong possibility that sialylated forms of apoE also were increased in tumorous tissues of HCC. ApoE level in tumorous tissues is frequently elevated and may be a good histological marker for HCC.

Adult↗
PubMed2005

Fibroblast growth factor 2 facilitates the differentiation of transplanted bone marrow cells into hepatocytes.

We have developed an in vivo mouse model, the green fluorescent protein (GFP)/carbon tetrachloride (CCl(4)) model, and have previously reported that transplanted GFP-positive bone marrow cells (BMCs) differentiate into hepatocytes via hepatoblast intermediates. Here, we have investigated the growth factors that are closely related to the differentiation of transplanted BMCs into hepatocytes, and the way that a specific growth factor affects the differentiation process in the GFP/CCl(4) model. We performed immunohistochemical analysis to identify an important growth factor in our model, viz., fibroblast growth factor (FGF). In liver samples, the expression of FGF1 and FGF2 and of FGF receptors (FGFRs; FGFR1, FGFR2) was significantly elevated with time after bone marrow transplantation (BMT) compared with other factors, and co-expression of GFP and FGFs or FGFRs could be detected. We then analyzed the effect and molecular mechanism of FGF signaling on the enhancement of BMC differentiation into hepatocytes by immunohistochemistry, immunoblotting, and microarray analysis. Treatment with recombinant FGF (rFGF), especially rFGF2, elevated the repopulation rate of GFP-positive cells in the liver and significantly increased the expression of both Liv2 (hepatoblast marker) and albumin (hepatocyte marker). Administration of rFGF2 at BMT also raised serum albumin levels and improved the survival rate. Transplantation of BMCs with rFGF2 specifically activated tumor necrosis factor-alpha (TNF-alpha) signaling. Thus, FGF2 facilitates the differentiation of transplanted BMCs into albumin-producing hepatocytes via Liv2-positive hepatoblast intermediates through the activation of TNF-alpha signaling. Administration of FGF2 in combination with BMT improves the liver function and prognosis of mice with CCl(4)-induced liver damage.

Animals↗
PubMed2005

The role of oxidative stress in NASH and fatty liver model.

The aim of this study was to investigate whether oxidative stress is related to the development of liver injury and an iron chelator, deferoxamine (DFO) can prevent lipid peroxidation resulting in reduced liver injury as well as reduce preneoplastic lesions induced by a choline-deficient l-amino acid-defined (CDAA) diet. CDAA diet administration resulted in an increased serum ALT level after one week. Hepatocytes in rat liver fed a CDAA diet showed malondialdehyde (MDA) accumulation. But simultaneous DFO treatment for one week reduced this elevation of ALT as well as MDA accumulation in the liver. Feeding rats a CDAA diet for 14 weeks led to the development of severe liver fibrosis and preneoplastic lesions detected as enzyme-altered lesions. DFO treatment also prevented the expression of activated stellate cells, resulting in the reduction of liver fibrosis as well as reducing the development of preneoplastic lesions. These results indicate that iron chelation can reduce the development of preneoplastic lesions in a CDAA diet model.

Journal Article↗
PubMed2005

Leptin enhances TNF-alpha production via p38 and JNK MAPK in LPS-stimulated Kupffer cells.

Leptin is now recognized as a proinflammatory cytokine and thought to be a progressive factor for non-alcoholic steatohepatitis (NASH). Here we showed the effects of leptin on the production of TNF-alpha (tumor necrosis factor-alpha) by Kupffer cells (KCs) with signal transduction. Leptin enhanced TNF-alpha production accompanied by a dose-dependent increase of MAPK activity in lipopolysaccharide (LPS)-stimulated KCs. SB203580 and JNK inhibitor I, specific inhibitors of P38 and JNK, inhibited TNF-alpha production in KCs but PD98059, an inhibitor of the ERK pathway, did not affect TNF-alpha production by KCs. Recombinant constitutively active adenovirus (Ad)-MKK6 and-MKK7 increased TNF-alpha production in KCs with activation of P38 and JNK without any change by Ad-MEK1 delivery. On the other hand, KCs isolated from the Zucker rat (fa/fa), a leptin receptor-deficient rat, showed reduced production of TNF-alpha on stimulation with LPS. The delivery of Ad-MKK6 and-MKK7, but not Ad-MEK1, increased TNF-alpha production in KCs of Zucker rats with activation of P38 and JNK. Addition of leptin to normal rats increased LPS-induced hepatic TNF-alpha production in vivo and leptin receptor-deficient Zucker rats showed reduced hepatic TNF-alpha production on addition of LPS in vivo. These findings indicate that P38 and JNK pathways are involved in the signal transduction of leptin enhancement of LPS-induced TNF-alpha production.

Animals↗
PubMed2005

Herbal medicine Rhei rhizome prevents liver fibrosis in rat liver cirrhosis induced by a choline-deficient L-amino acid-defined diet.

The aim of this study was to investigate whether herbal medicine Rhei rhizome, extract powder from herbs, has influences on the development of liver fibrosis. In in vivo studies the effects of Rhei rhizome were examined using the choline-deficient L-amino acid-defined (CDAA) diet-induced liver fibrosis model. In In vitro studies the effects of Rhei rhizome on type I procollagen mRNA expression, alpha-smooth muscle actin (alpha-SMA), metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) of isolated hepatic stellate cell were examined. In vivo Rhei rhizome prevented fibrosis in a dose-dependent manner up to 1.0% (w/w) with a reduced number of activated stellate cells. In vitro the Rhei rhizome prevented stellate cell activation resulting in reduced type I procollagen mRNA, alpha-SMA and TIMP-1, 2 expression. These results indicate that Rhei rhizome significantly reduces liver fibrosis by the direct inhibition of stellate cell activation without reducing hepatocyte cell death.

Actins↗
PubMed2005

The effect of a late evening snack in patients with liver cirrhosis.

OBJECTIVES: : As an intervention for energy malnutrition, frequent meals or a late evening snack (LES) has been recently recommended. On the other hand, it has been reported that glucose intolerance is found in approximately 70% of patients with liver cirrhosis. Thus, we investigated which would be better for the improvement of energy malnutrition and glucose intolerance, treatment with LES alone or LES plus divided meals. METHODS: : One group of oral supplementation with one pack of a branched-chain amino acid (BCAA)-enriched nutrient, Aminoleban EN (210kcal), at 10 p.m. LES and the other group with two packs of Aminoleban EN (one pack at 10 p.m. as LES and another pack during the day, i.e. at sometime from 10 a.m. to 3 p.m.) were examined to determine the influence of LES on the blood glucose level, biochemical parameters, and energy metabolism. Twenty-six patients participated in this study. The administration period was 7 days. Metabolic measurements were performed using an indirect calorimeter. RESULTS: : The fat oxidation rate was significantly decreased and the carbohydrate oxidation rate significantly increased in both groups. As a result, respiratory quotient (RQ) was significantly improved. In many cases, the increase of the glucose level after meals seemed to be reduced after LES administration for 1 week. LES could improve energy malnutrition, and correct amino acid imbalance. There was also a significant correlation between non-protein respiratory quotient (npRQ) and the creatinine height index. CONCLUSION: : LES alone improved the energy malnutrition state and glucose intolerance equivalent to LES plus divided meals. Thus, LES may improve glucose intolerance in patients with liver cirrhosis.

Journal Article↗
PubMed2005

Lesson from the GFP/CCl4 model--translational research project: the development of cell therapy using autologous bone marrow cells in patients with liver cirrhosis.

The plasticity of bone marrow has been confirmed by the analysis of autopsy findings in female recipients of bone marrow cells transplanted from male donors. To establish new clinical cell therapies using autologous bone marrow cells for patients with liver failure, we developed a new in vivo model, the "green fluorescent protein (GFP)/carbon tetrachloride (CCl(4)) model". Using the GFP/CCl(4) model, we found that transplanted Liv8-negative cells efficiently repopulated into cirrhotic liver tissue and trans-differentiated into albumin-producing hepatocytes under conditions of persistent liver damage induced by CCl(4). Moreover, one marrow cell transplantation into liver cirrhosis mice improved their liver function, ameliorated liver fibrosis, and improved their survival rate. Results from the GFP/CCl(4) model showed that cell therapy using autologous bone marrow cells has the potential to become an effective treatment for patients with liver failure. Here we describe the findings from the GFP/CCl(4) model and the scope of the translational research project.

Animals↗