Munechika Enjoji

Fukuoka University, Hukuoka, Fukuoka, Japan

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Publications (189)612.12 Total impact

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    ABSTRACT: Self-measured salt excretion from overnight urine samples shows significant correlation with 24-h-urinary salt excretion, but it is not known whether a self-measuring method can monitor daily fluctuations in individual salt consumption. In this study, we measured salt excretion from 24-h urine samples (24-h salt) in 50 volunteers over 3 test days (2 weekdays and 1 holiday), and examined to what extent the values correlated with estimates of 24-h salt excretion from overnight urine samples obtained using a self-monitoring device (ON salt). Urine collection was considered successful when the difference between the predicted and actual 24-h-urinary creatinine excretion was within 30%. Thirty-three (M/F=7/26; 39.6±16.7 years) out of 50 participants completed their urine collections successfully and their samples were used in the analysis. Twenty-four-hour salt and ON salt did not significantly differ between test days and between the weekdays and the holiday. Moreover, there was a significant positive correlation between 24-h salt and ON salt for each test day. The coefficients of variation (CVs) for 24-h salt among test days and among subjects were 24.7% and 21.3%, respectively. The CVs for ON salt were lower than those for 24-h salt (13.3% and 17.7%, respectively). In conclusion, self-measurement of salt excretion from overnight urine samples allows estimation of daily salt intake; thus, the use of a self-monitoring device may be a useful motivational tool for personal salt restriction.Hypertension Research advance online publication, 12 November 2015; doi:10.1038/hr.2015.121.
    No preview · Article · Nov 2015 · Hypertension Research
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    ABSTRACT: Background and aim: White opaque substance (WOS) is a novel endoscopic finding in gastric neoplasms, indicating the intracellular accumulation of lipid droplets (LDs). However, gastric lipid metabolism has not been extensively investigated, even in normal mucosa. We investigated the expression profiles of lipid-metabolism-associated genes in gastric neoplasms. Methods: Thirty-four patients with early gastric cancer or adenoma were enrolled in this study. Paired biopsy samples from tumor and adjacent non-tumor areas were obtained and analyzed by real-time polymerase chain reaction. Endoscopically resected specimens were evaluated histopathologically. Results: Genes associated with β-oxidation (peroxisome proliferator-activated receptor α, carnitine palmitoyltransferase 1a, hydroxyacyl-CoA dehydrogenase), lipoprotein excretion (apolipoprotein B, microsomal triglyceride transfer protein, acyl-CoA:cholesterol acyltransferase 2), fatty acid transport (fatty acid-binding protein), construction of triglycerides in the endoplasmic reticulum (acyl-CoA:diacylglycerol acyltransferase 1), and LD degradation/lipolysis (comparative gene identification-58, adipose triglyceride lipase) were significantly downregulated in neoplasms compared with non-tumor areas. Pyruvate dehydrogenase lipoamide kinase isozyme 4 (negative regulator of glycolysis) and adipophilin (LD surface component) were also repressed. Conversely, expression levels of genes associated with de novo lipogenesis (sterol regulatory element-binding protein 1c, acyl-CoA:diacylglycerol acyltransferase 2) were significantly enhanced in neoplasms. There was no significant difference in gene expression levels between carcinomas and adenomas, or between WOS-positive and -negative neoplasms. Conclusion: Gene expression profiles in neoplasms suggest a predominance of lipid storage (lipogenesis/LD formation) over consumption (β-oxidation/excretion/lipolysis). Lipid accumulation and WOS in gastric epithelial neoplasms may be caused by impaired mitochondrial oxidation, lipoprotein excretion, and LD degradation.
    No preview · Article · Oct 2015 · Journal of Gastroenterology and Hepatology
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    Preview · Article · Jul 2015
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    ABSTRACT: The 5-hydroxytryptamine (5-HT) 1A receptors are considered a potential target for the treatment of mental and neuropsychiatric disorders. Several studies have indicated that 5-HT1A receptor agonists increase hippocampal neurogenesis, which is implicated in the action mechanism of antidepressants. However, these agents have not been applied to humans due to intolerable side effects. We recently showed that chronic administration of tandospirone, a clinically available 5-HT1A receptor partial agonist, increased hippocampal neurogenesis dose-dependently. The present study was done to determine if chronic tandospirone treatment has antidepressant potential from the standpoint of hippocampal neurogenesis and behavior. Male Sprague-Dawley rats were intraperitoneally administered a vehicle or tandospirone (10mg/kg) once daily for 28 days. Two weeks after starting the injections, animals were exposed to intermittent social defeat (four times over two weeks). The effects of stress and tandospirone on the rodents׳ behavior were evaluated by the Novelty-Suppressed Feeding (NSF) test. The quantification of hippocampal neurogenesis was estimated using immunostaining with Ki-67 and doublecortin (DCX). Chronic tandospirone treatment reversed the psychosocial stress-induced increase in the latency in the NSF test and decrease in the density of DCX-positive cells in the dentate gyrus of the dorsal and ventral hippocampus. However, no difference in the density of Ki-67-positive cells was observed between the vehicle- and tandospirone-administered groups. To clarify the antidepressant potential of TDS, the other behavioral tests for depression will be required. Our findings suggest that tandospirone has antidepressant potential through an inhibiting effect on stress-induced changes in hippocampal neurogenesis. Copyright © 2015 Elsevier B.V. All rights reserved.
    No preview · Article · Apr 2015 · Journal of Affective Disorders
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    ABSTRACT: To investigate the relationship between the iron-metabolism-related gene expression profiles and efficacy of antiviral therapy in chronic hepatitis C patients. The hepatic expression profile of iron-metabolism-related genes was analyzed and its association with virological response to pegylated-interferon plus ribavirin combination therapy was evaluated. A hundred patients with chronic hepatitis C (genotype1b, n = 50; genotype 2, n = 50) were enrolled and retrospectively analyzed. Liver biopsy samples were subjected to quantitative polymerase chain reaction for iron-metabolism-related genes and protein expression (Western blotting analysis) for ferroportin. As a control, normal liver tissue was obtained from 18 living donors of liver transplantation. Serum hepcidin level was measured by sensitive liquid chromatography/electrospray ionization tandem mass spectrometry. Iron overload is associated with liver damage by increasing oxidative stress and hepatitis C virus (HCV) is reported to induce iron accumulation in hepatocytes in vivo. Conversely, iron administration suppresses HCV replication in vitro. Therefore, the association between HCV infection and iron metabolism remains unclear. Compared with controls, patients had significantly higher gene expression for transferrin, iron-regulatory proteins 1 and 2, divalent metal transporter 1, and ferroportin, but similar for transferrin receptors 1 and 2, and hepcidin. When the expression profiles were compared between sustained virological response (SVR) and non-SVR patients, the former showed significantly lower transcription and protein expression of hepcidin and ferroportin. Expression of hepcidin-regulating genes, BMPR1, BMPR2, and hemojuvelin, was significantly increased, whereas BMP2 was decreased in HCV-infected liver. BMPR2 and hemojuvelin expression was significantly lower in the SVR than non-SVR group. HCV infection affects the expression of iron-metabolism-related genes, leading to iron accumulation in hepatocytes. Decreased expression of hepcidin and ferroportin in SVR patients indicates the importance of hepatocytic iron retention for viral response during pegylated-interferon plus ribavirin treatment.
    No preview · Article · Mar 2015
  • Susumu Koyama · Munechika Enjoji · Mark S. Brodie · Sarah B. Appel

    No preview · Article · Jan 2015 · Journal of Biomedical Science and Engineering
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    ABSTRACT: Reduced cellular uptake of menaquinone-4 (MK-4), a vitamin K2 homolog, in human hepatocellular carcinoma (HCC) limits its usefulness as a safe long-term anti-tumor agent for recurrent HCC and produces des-γ-carboxy prothrombin (DCP). We hypothesized that effective delivery of menahydroquinone-4 (MKH), the active form of MK-4 for γ-glutamyl carboxylation, into HCC cells is critical for regulating HCC growth, and may enable it to be applied as a safe anti-tumor agent. In this study, we verified this hypothesis using menahydroquinone-4 1,4-bis-N,N-dimethylglycinate hydrochloride (MKH-DMG), a prodrug of MKH, and demonstrated its effectiveness. Intracellular delivery of MKH and subsequent growth inhibition of PLC/PRF/5 and Hep3B (DCP-positive) and SK-Hep-1 (DCP-negative) cells after MKH-DMG administration was determined and compared with MK-4. The activity of MKH-DMG against tumor progression in the liver alongside DCP formation was determined in a spleen-liver metastasis mouse model. MKH-DMG exhibited greater intracellular delivery of MKH in vitro (AUC0-72h of MKH) and increased growth inhibitory activity against both DCP-positive and DCP-negative HCC cell lines. The phenomena of MKH delivery into cells in parallel with simultaneous growth inhibition suggested that MKH is the active form for growth inhibition of HCC cells. Cell cycle arrest was determined to be involved in the growth inhibition mechanisms of MKH-DMG. Furthermore, MKH-DMG showed significant inhibition of tumor progression in the liver, and a substantial decrease in plasma DCP levels in the spleen-liver metastasis mouse model. Our results suggest that MKH-DMG is a promising new candidate anti-tumor agent for safe long-term treatment of HCC. Copyright © 2014, American Association for Cancer Research.
    No preview · Article · Nov 2014 · Cancer Prevention Research
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    ABSTRACT: The objective was to investigate the validity of a self-monitoring device that estimates 24-h urinary salt excretion from overnight urine samples as a tool for education regarding salt restriction. Twenty healthy volunteers consumed test meals for 14 days, with salt content as follows: 10 g (days 1-5); 5 g (days 6-8, 12 and 14); and 13 g (days 9-11 and 13). On days 2-15, urinary salt excretion was estimated from overnight urine samples by a self-monitoring device. Twenty-four-hour urine samples were collected on days 5 and 8 to measure salt excretion directly. Blood pressure was measured in the morning and during sleep on days 1-15. Estimated urinary salt excretion measured by the device showed a correlation with salt intake, and the ratio of estimated urinary salt excretion to salt intake was 0.84±0.10 (days 2-6), 1.27±0.28 (days 7-9), 0.70±0.11 (days 10-12), 1.37±0.22 (day 13), 0.68±0.13 (day 14) and 1.33±0.19 (day 15). The correlation between estimated urinary salt excretion measured by a device and directly measured 24-h urinary salt excretion was significant (r=0.65, P<0.05) during the period of 10 g salt intake, but not during 5 g salt intake. Blood pressure in the morning was not influenced by the change in salt intake, but systolic pressure during sleep showed a significant increase or decrease according to the levels of salt intake. In conclusion, a self-monitoring device, which can estimate 24-h urinary salt excretion from overnight urine samples, is considered to be a practical tool for education regarding salt restriction, although a similar future investigation is needed in older and/or hypertensive subjects.Hypertension Research advance online publication, 23 October 2014; doi:10.1038/hr.2014.155.
    No preview · Article · Oct 2014 · Hypertension Research

  • No preview · Article · May 2014 · Gastroenterology

  • No preview · Article · Apr 2014 · Journal of Hepatology
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    ABSTRACT: To investigate the metabolic changes in skeletal muscle and/or adipose tissue in glucagon-like peptide-1-induced improvement of nonalcoholic fatty liver disease (NAFLD). Male Wistar rats were fed either a control diet (control group) or a high-fat diet (HFD). After 4 wk, the HFD-fed rats were subdivided into two groups; one group was injected with exenatide [HFD-Ex(+) group] and the other with saline [HFD-Ex(-) group] every day for 12 wk. The control group received saline and were fed a control diet. Changes in weight gain, energy intake, and oxygen consumption were analyzed. Glucose tolerance tests were performed after 8 wk of treatment. Histological assessments were performed in liver and adipose tissue. RNA expression levels of lipid metabolism related genes were evaluated in liver, skeletal muscle, and adipose tissue. Exenatide attenuated weight gain [HFD-Ex(-) vs HFD-Ex(+)] and reduced energy intake, which was accompanied by an increase in oxygen consumption and a decrease in the respiratory exchange ratio [HFD-Ex(-) vs HFD-Ex(+)]. However, exenatide did not affect glucose tolerance. Exenatide reduced lipid content in the liver and adipose tissue. Exenatide did not affect the expression of lipid metabolism-related genes in the liver or skeletal muscle. In adipose tissue, exenatide significantly upregulated lipolytic genes, including hormone-sensitive lipase, carnitine palmitoyltransferase-1, long-chain acyl-CoA dehydrogenase, and acyl-CoA oxidase 1 [HFD-Ex(-) vs HFD-Ex(+)]. Exenatide also upregulated catalase and superoxide dismutase 2 [HFD-Ex(-) vs HFD-Ex(+)]. In addition to reducing appetite, enhanced lipid use by exenatide in adipose tissue may reduce hepatic lipid content in NAFLD, most likely by decreasing lipid influx into the liver.
    No preview · Article · Mar 2014 · World Journal of Gastroenterology
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    ABSTRACT: Background & AimsInjury to biliary epithelial cells caused by disorders in bile composition may be the initial step in the pathogenesis of primary biliary cirrhosis (PBC). We therefore examined choline/phospholipid metabolism in livers of patients with PBC. Methods Hepatic levels of mRNA encoded by choline metabolism-related genes in early stage PBC patients were quantified by real-time RT-PCR. Serum cholesterol and triglyceride concentrations in each lipoprotein compartment and serum/tissue choline levels were also measured. OCT1 expression was quantified by genotype (rs683369 and rs622342). ResultsSerum choline concentrations were significantly higher in PBC patients than in normal individuals, with the concentrations in the former lowered by treatment with fibrates. Hepatic choline levels were markedly lower in PBC patients than in controls. The levels of expression of genes associated with choline uptake (OCT1 and CTL1), phosphatidylcholine synthesis (PEMT and BHMT), and phosphatidylcholine transport (MDR3) were significantly upregulated in PBC compared with control livers. Serum cholesterol concentrations and the cholesterol/triglyceride ratio in serum VLDL were markedly higher in PBC patients than in controls. In PBC liver, OCT1 protein levels were lower in patients with minor (CG/GG at rs683369 and/or CC at rs622342) than major (CC at rs683369 and AA at rs622342) genotypes of the OCT1 gene. Conclusions During early stage PBC, hepatocellular choline uptake and PC synthesis become dysregulated. OCT1 genotypes may influence the pathogenesis of PBC.This article is protected by copyright. All rights reserved.
    No preview · Article · Mar 2014 · Liver international: official journal of the International Association for the Study of the Liver
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    ABSTRACT: Nonalcoholic fatty liver disease (NAFLD) is one of the most frequent causes of health problems in Western (industrialized) countries. Moreover, the incidence of infantile NAFLD is increasing, with some of these patients progressing to nonalcoholic steatohepatitis. These trends depend on dietary habits and life-style. In particular, overeating and its associated obesity affect the development of NAFLD. Nutritional problems in patients with NAFLD include excess intake of energy, carbohydrates, and lipids, and shortages of polyunsaturated fatty acids, vitamins, and minerals. Although nutritional therapeutic approaches are required for prophylaxis and treatment of NAFLD, continuous nutrition therapy is difficult for many patients because of their dietary habits and lifestyle, and because the motivation for treatment differs among patients. Thus, it is necessary to assess the nutritional background and to identify nutritional problems in each patient with NAFLD. When assessing dietary habits, it is important to individually evaluate those that are consumed excessively or insufficiently, as well as inappropriate eating behaviors. Successful nutrition therapy requires patient education, based on assessments of individual nutrients, and continuing the treatment. In this article, we update knowledge about NAFLD, review the important aspects of nutritional assessment targeting treatment success, and present some concrete nutritional care plans which can be applied generally.
    No preview · Article · Feb 2014 · World Journal of Gastroenterology

  • No preview · Article · Feb 2014 · Fukuoka igaku zasshi = Hukuoka acta medica
  • Susumu Koyama · Munechika Enjoji · Mark S. Brodie · Sarah B. Appel

    No preview · Article · Jan 2014 · Journal of Biomedical Science and Engineering
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    ABSTRACT: Although the mechanisms responsible for acute liver failure (ALF) have not yet been fully elucidated, studies have indicated that intrahepatic macrophage activation plays an important role in the pathogenesis of ALF through intrahepatic microcirculatory disorder and consequent parenchymal cell death. Intrahepatic microcirculatory disorder has been demonstrated in animal models using intravital microscopy; however, the limitations of this method include simultaneously evaluating blood flow and the surrounding pathological changes. Therefore, in this study, we devised a novel method involving tetramethylrhodamine isothiocyanate (TRITC)-dextran administration for the pathological assessment of hepatic microcirculation. In addition, we aimed to elucidate the mechanisms through which intrahepatic microcirculatory disorder progresses with relation to activated macrophages. ALF was induced in Wistar rats by exposure to lipopolysaccharide and D-galactosamine. Intrahepatic microcirculation and microcirculatory disorder in zone 3 (pericentral zone) of the livers of rats with ALF was observed. Immunohistochemical examinations in conjunction with TRITC-dextran images revealed that the macrophages were mainly distributed in zone 2 (intermediate zone), while cleaved caspase-3-positive hepatocytes, pimonidazole and hypoxia-inducible factor 1-α were abundant in zone 3. We also found that 4-hydroxy-2-nonenal and nicotinamide adenine dinucleotide phosphate oxidase (NOX)4-positive cells were predominantly located in the zone 3 parenchyma. The majority of apoptotic hepatocytes in zone 3 were co-localized with NOX4. Our results revealed that the apoptotic cells in zone 3 were a result of hypoxic conditions induced by intrahepatic microcirculatory disorder, and were not induced by activated macrophages. The increased levels of oxidative stress in zone 3 may contribute to the progression of hepatocyte apoptosis.
    Full-text · Article · Dec 2013 · International Journal of Molecular Medicine
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    ABSTRACT: To analyzed the association between inosine triphosphatase (ITPA) (rs1127354) genotypes and sustained virological response (SVR) rates in peginterferon (Peg-IFN)α + ribavirin (RBV) treatment. Patients who underwent Peg-IFNα + RBV combination therapy were enrolled (n = 120) and they had no history of other IFN-based treatments. Variation in hemoglobin levels during therapy, cumulative reduction of RBV dose, frequency of treatment withdrawal, and SVR rates were investigated in each ITPA genotype. In patients with ITPA CC genotype, hemoglobin decline was significantly greater and the percentage of patients in whom total RBV dose was < 60% of standard and/or treatment was withdrawn was significantly higher compared with CA/AA genotype. However, SVR rates were equivalent between CC and CA/AA genotypes, and within a subset of patients with Interleukin 28B (IL28B) (rs8099917) TT genotype, SVR rates tended to be higher in patients with ITPA CC genotype, although the difference was not significant. ITPA CC genotype was a disadvantageous factor for Peg-IFNα + RBV treatment in relation to completion rates and RBV dose. However, CC genotype was not inferior to CA/AA genotype for SVR rates. When full-length treatment is accomplished, it is plausible that more SVR is achieved in patients with ITPA CC variant, especially in a background of IL28B TT genotype.
    No preview · Article · Aug 2013

  • No preview · Article · Apr 2013

  • No preview · Article · Apr 2013
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    ABSTRACT: Despite the use of pegylated-interferon (peg-IFN) plus ribavirin combination therapy, many patients infected with hepatitis C virus (HCV)-1b remain HCV-positive. To determine whether addition of pitavastatin and eicosapentaenoic acid (EPA) is beneficial, the "add-on" therapy option (add-on group) was compared retrospectively with unmodified peg-IFN/ribavirin therapy (standard group). Association of host- or virus-related factors with sustained virological response was assessed. In HCV replicon cells, the effects of pitavastatin and/or EPA on HCV replication and expression of innate-immunity- and lipid-metabolism-associated genes were investigated. In patients infected with HCV-1b, sustained virological response rates were significantly higher in the add-on than standard group. In both groups, sustained virological response rates were significantly higher in patients with genotype TT of IL-28B (rs8099917) than in those with non-TT genotype. Among the patients with non-TT genotype, sustained virological response rates were markedly higher in the add-on than standard group. By multivariate analysis, genome variation of IL28B but not add-on therapy remained as a predictive factor of sustained virological response. In replicon cells, pitavastatin and EPA suppressed HCV replication. Activation of innate immunity was obvious in pitavastatin-treated cells and EPA suppressed the expression of sterol regulatory element binding protein-1c and low-density lipoprotein receptor. Addition of pitavastatin and EPA to peg-IFN/ribavirin treatment improved sustained virological response in patients infected with HCV-1b. Genotype variation of IL-28B is a strong predictive factor in add-on therapy. J. Med. Virol. © 2012 Wiley Periodicals, Inc.
    No preview · Article · Feb 2013 · Journal of Medical Virology

Publication Stats

3k Citations
612.12 Total Impact Points


  • 2005-2015
    • Fukuoka University
      • Faculty of Pharmaceutical Sciences
      Hukuoka, Fukuoka, Japan
  • 1994-2010
    • Kyushu University
      • • Division of Host Defense
      • • Graduate School of Medical Sciences
      • • Division of Internal Medicine
      Hukuoka, Fukuoka, Japan
  • 1997-2000
    • Baylor College of Medicine
      • Department of Medicine
      Houston, Texas, United States