Kyushu University Academic Staff Educational and Research Activities Database
List of Papers
Masatake Tanaka Last modified date:2022.05.21

Assistant Professor / Department of Medicine and Bioregulatory Science, Graduate School of Medical Sciences, Kyushu University / Department of Hepatology and Pancreatology / Kyushu University Hospital

1. Akifumi Kuwano, Masatake Tanaka, Hideo Suzuki, Miho Kurokawa, Koji Imoto, Shigeki Tashiro, Takeshi Goya, Motoyuki Kohjima, Masaki Kato, Yoshihiro Ogawa, Upregulated expression of hypoxia reactive genes in peripheral blood mononuclear cells from chronic liver disease patients., Biochemistry and biophysics reports, 10.1016/j.bbrep.2021.101068, 27, 101068-101068, 2021.09, Liver fibrosis induces intrahepatic microcirculation disorder and hypoxic stress. Hypoxic stress has the potential for an increase in the possibility of more liver fibrosis and carcinogenesis. Liver biopsy is a standard method that evaluates of intrahepatic hypoxia, however, is invasive and has a risk of bleeding as a complication. Here, we investigated the hypoxia reactive gene expressions in peripheral blood mononuclear cells (PBMC) from chronic liver disease patients to evaluate intrahepatic hypoxia in a non-invasive manner. The subjects enrolled for this study were composed of 20 healthy volunteers (HV) and 48 patients with chronic liver disease (CLD). CLD patients contained 24 patients with chronic hepatitis(CH)and 24 patients with liver cirrhosis (LC). PBMC were isolated from heparinized peripheral blood samples. We measured the transcriptional expression of hypoxia reactive genes and inflammatory cytokines by quantitative RT-PCR. mRNA expression of adrenomedullin (AM), vascular endothelial growth factor A (VEGFA) superoxide dismutase (SOD), glutathione peroxidase (GPx) (p < 0.05), Interleukin-6 (IL-6), transforming growth factor-beta (TGF-β) and heme oxygenase-1 (HO-1) in CLD group were significantly higher than HV. AM mRNA expression is correlated with serum lactate dehydrogenase (LDH), serum albumin (Alb), IL6, and SOD mRNA expression. The hypoxia reactive gene expression in PBMCs from CLD patients was more upregulated than HV. Especially, angiogenic genes were notably upregulated and correlated with liver fibrosis. Here, we suggest that mRNA expression of AM in PBMCs could be the biomarker of intrahepatic hypoxia..
2. Akifumi Kuwano, Miho Kurokawa, Motoyuki Kohjima, Koji Imoto, Shigeki Tashiro, Hideo Suzuki, Masatake Tanaka, Seiji Okada, Masaki Kato, Yoshihiro Ogawa, Microcirculatory disturbance in acute liver injury., Experimental and therapeutic medicine, 10.3892/etm.2021.10028, 21, 6, 596-596, 2021.06, Microcirculatory disturbance is thought to be involved in the pathogenesis of acute liver injury (ALI). The current study examined the pathophysiologic role of hepatic microcirculatory disturbance in patients with ALI and in mouse models of ALI. Using serum aminotransferase (ALT)/lactate dehydrogenase (LDH) ratio as a hypoxic marker, 279 patients with ALI were classified into the low ALT/LDH ratio (ALT/LDH ≤1.5) and high ALT/LDH ratio group (ALT/LDH >1.5). In the low ALT/LDH ratio group, serum ALT, LDH, fibrinogen degradation products and prothrombin time-international normalized ratio were increased relative to the high ALT/LDH ratio group. Histologically, hepatic expression of tissue factor (TF) and hypoxia-related proteins was enhanced in the low ALT/LDH ratio group, and this was accompanied by sinusoidal fibrin deposition. Sinusoidal hypercoagulation and intrahepatic hypoxia was also analyzed in two different mouse models of ALI; Concanavalin A (ConA) mice and Galactosamine/tumor necrosis factor (TNF)-α (G/T) mice. Serum ALT/LDH ratio in ConA mice was significantly lower compared with G/T mice. Pimonidazole staining revealed the upregulation of hypoxia-related proteins in ConA mice. Recombinant human soluble thrombomodulin improved liver damage in ConA mice in association with reduced sinusoidal hypercoagulation and intrahepatic hypoxia. The present study provides evidence that serum ALT/LDH ratio aids in the identification of patients with ALI and intrahepatic hypoxia as a result of microcirculatory disturbance. The results facilitate the improved understanding of the pathogenesis of ALI, thereby offering a novel therapeutic strategy against ALI, which arises from sinusoidal hypercoagulation..
3. Hiroaki Okuno, Haruei Ogino, Eikichi Ihara, Kei Nishioka, Yoshimasa Tanaka, Takatoshi Chinen, Motoyuki Kohjima, Takamasa Oono, Masatake Tanaka, Takeshi Goya, Nao Fujimori, Yoichiro Iboshi, Takuji Gotoda, Yoshihiro Ogawa, Discriminant equation using mucosally expressed cytokines and transcription factor for making definite diagnosis of inflammatory bowel disease unclassified., BMC gastroenterology, 10.1186/s12876-021-01656-1, 21, 1, 73-73, 2021.02, BACKGROUND: The pathological conditions of UC and CD involved in inflammatory bowel disease-unclassified (IBD-U), UC with primary sclerosing cholangitis (PSC-UC), and UC with autoimmune pancreatitis type 2 (AIP-UC) remain unclear. Therefore, it is difficult to decide the appropriate treatments for these subtypes of UC. Our aim was to examine whether the discriminant equation using the mucosally expressed mediators designed as our previous study for IBD, could characterize IBD-U, PSC-UC, or AIP-UC. METHODS: A total of 56 patients including UC (n = 24), CD (n = 15), IBD-U (n = 10), PSC-UC (n = 4), and AIP-UC (n = 3), along with 9 control patients were enrolled in this study. Mucosally expressed inflammatory mediators related to Th1, Th2, Th17, and Treg were measured using quantitative PCR in endoscopic biopsies from the inflamed intestines of the patients. The IBD-U, PSC-UC or AIP-UC were characterized using discriminant analysis and principle component analysis. RESULTS: Through discriminant analyses, combinations of 3 to 7 inflammatory mediators were used to discriminate between UC and CD. Moreover, the identified 3 markers could diagnose patients with IBD-U as UC or CD with high accuracy. The distribution graph of inflammatory mediators using the principal component analysis revealed that PSC-UC and AIP-UC exhibited CD-like and UC-like features, respectively. CONCLUSIONS: The discriminant equation using mucosally expressed mediators of IL-13, IL-21 and T-bet can be used as a universal diagnostic tool not only for IBD-U but also to assess pathological conditions in PSC-UC and AIP-UC..
4. Shingo Yoshizaki, Tetsuya Tamaru, Masamitsu Hara, Ken Kijima, Masatake Tanaka, Dai-Jiro Konno, Yoshihiro Matsumoto, Yasuharu Nakashima, Seiji Okada, Microglial inflammation after chronic spinal cord injury is enhanced by reactive astrocytes via the fibronectin/β1 integrin pathway., Journal of neuroinflammation, 10.1186/s12974-020-02059-x, 18, 1, 12-12, 2021.01, BACKGROUND: After spinal cord injury (SCI), glial scarring is mainly formed around the lesion and inhibits axon regeneration. Recently, we reported that anti-β1 integrin antibody (β1Ab) had a therapeutic effect on astrocytes by preventing the induction of glial scar formation. However, the cellular components within the glial scar are not only astrocytes but also microglia, and whether or not β1Ab treatment has any influence on microglia within the glial scar remains unclear. METHODS: To evaluate the effects of β1Ab treatment on microglia within the glial scar after SCI, we applied thoracic contusion SCI to C57BL/6N mice, administered β1Ab in the sub-acute phase, and analyzed the injured spinal cords with immunohistochemistry in the chronic phase. To examine the gene expression in microglia and glial scars, we selectively collected microglia with fluorescence-activated cell sorting and isolated the glial scars using laser-captured microdissection (LMD). To examine the interaction between microglia and astrocytes within the glial scar, we stimulated BV-2 microglia with conditioned medium of reactive astrocytes (RACM) in vitro, and the gene expression of TNFα (pro-inflammatory M1 marker) was analyzed via quantitative polymerase chain reaction. We also isolated both naïve astrocytes (NAs) and reactive astrocytes (RAs) with LMD and examined their expression of the ligands for β1 integrin receptors. Statistical analyses were performed using Wilcoxon's rank-sum test. RESULTS: After performing β1Ab treatment, the microglia were scattered within the glial scar and the expression of TNFα in both the microglia and the glial scar were significantly suppressed after SCI. This in vivo alteration was attributed to fibronectin, a ligand of β1 integrin receptors. Furthermore, the microglial expression of TNFα was shown to be regulated by RACM as well as fibronectin in vitro. We also confirmed that fibronectin was secreted by RAs both in vitro and in vivo. These results highlighted the interaction mediated by fibronectin between RAs and microglia within the glial scar. CONCLUSION: Microglial inflammation was enhanced by RAs via the fibronectin/β1 integrin pathway within the glial scar after SCI. Our results suggested that β1Ab administration had therapeutic potential for ameliorating both glial scar formation and persistent neuroinflammation in the chronic phase after SCI..
5. Kojiro Hata, Kimitaka Suetsugu, Nobuaki Egashira, Yoko Makihara, Shinji Itoh, Tomoharu Yoshizumi, Masatake Tanaka, Motoyuki Kohjima, Hiroyuki Watanabe, Satohiro Masuda, Ichiro Ieiri, Association of lenvatinib plasma concentration with clinical efficacy and adverse events in patients with hepatocellular carcinoma., Cancer chemotherapy and pharmacology, 10.1007/s00280-020-04178-x, 86, 6, 803-813, 2020.12, PURPOSE: This study aimed to examine the association between the trough plasma concentration of lenvatinib with the objective response rate (ORR) and adverse events in patients with hepatocellular carcinoma (HCC). METHODS: Twenty-one patients with HCC who received lenvatinib were enrolled. We examined the median trough concentration (Ctrough median) of plasma lenvatinib until the first clinical response evaluation. The receiver-operating characteristic curve was drawn to show the discrimination potential of the Ctrough median for the ORR, using the modified Response Evaluation Criteria in Solid Tumors. Adverse events were graded based on the Common Terminology Criteria for Adverse Events (ver. 5.0). RESULTS: The Ctrough median values in the complete response and partial response group were significantly higher than those in the stable disease and progressive disease groups. The ORR was significantly higher in the high-Ctrough median group (≥ 42.68 ng/mL) than in the low-Ctrough median group (< 42.68 ng/mL) (80.0% vs. 18.2%; p = 0.0089). Although there was no difference in the occurrence of most adverse events between the high- and low-Ctrough median groups, the occurrence of any grade anorexia (100.0% vs. 45.5%; p = 0.0124) and grade 3 serious hypertension (70.0% vs. 18.2%; p = 0.0300) was significantly higher in the high-Ctrough median group than in the low-Ctrough median group. Multivariate analysis showed that high-Ctrough median was significantly associated with ORR development (odds ratio, 15.00; 95% confidence interval, 1.63-138.16; p = 0.0168). CONCLUSION: Maintaining Ctrough median above 42.68 ng/mL was crucial for achieving the ORR in patients with HCC..
6. Shingo Yoshizaki, Kazuya Yokota, Kensuke Kubota, Takeyuki Saito, Masatake Tanaka, Dai-Jiro Konno, Takeshi Maeda, Yoshihiro Matsumoto, Yasuharu Nakashima, Seiji Okada, The beneficial aspects of spasticity in relation to ambulatory ability in mice with spinal cord injury., Spinal cord, 10.1038/s41393-019-0395-9, 58, 5, 537-543, 2020.05, STUDY DESIGN: Experimental study with mice. OBJECTIVES: Spasticity is a common complication after spinal cord injury (SCI) and has detrimental aspects, such as persistent pain and involuntary muscle spasms. This study aimed to assess the influence of antispastic therapy on locomotor function after SCI. SETTING: University-based laboratory in Fukuoka, Japan. METHODS: A mouse model of spasticity was developed by producing incomplete SCI at the 9th thoracic level. At 8 weeks after SCI, an antispastic drug, baclofen, was intraperitoneally administered to six injured and two sham-operated mice. The severity of spasticity was evaluated by the modified Ashworth scoring (MAS) system, and locomotor function was evaluated by the Basso-Beattie-Bresnahan (BBB) scale/Basso mouse score (BMS). RESULTS: The administration of baclofen significantly improved spasticity in the SCI mice and the mean MAS decreased to from 6.2 to 2.8. However, at the same time, it significantly exacerbated the locomotor dysfunction of the SCI mice and the mean BMS decreased from 4.7 to 2.3. The time-course of the changes in locomotor function coincided with the time-course of the spasticity score. We also confirmed that the administration of baclofen was not associated with any changes in either locomotor function or spasticity of the sham-operated control mice. CONCLUSIONS: Our results suggest that spasticity has a certain beneficial effect on ambulation ability. It is important to note that antispastic treatments may be associated with a risk of impairing the preserved function of chronic SCI patients..
7. Shingo Yoshizaki, Ken Kijima, Masamitsu Hara, Takeyuki Saito, Tetsuya Tamaru, Masatake Tanaka, Dai-Jiro Konno, Yasuharu Nakashima, Seiji Okada, Tranexamic acid reduces heme cytotoxicity via the TLR4/TNF axis and ameliorates functional recovery after spinal cord injury., Journal of neuroinflammation, 10.1186/s12974-019-1536-y, 16, 1, 160-160, 2019.07, BACKGROUND: Spinal cord injury (SCI) is a catastrophic trauma accompanied by intralesional bleeding and neuroinflammation. Recently, there is increasing interest in tranexamic acid (TXA), an anti-fibrinolytic drug, which can reduce the bleeding volume after physical trauma. However, the efficacy of TXA on the pathology of SCI remains unknown. METHODS: After producing a contusion SCI at the thoracic level of mice, TXA was intraperitoneally administered and the bleeding volume in the lesion area was quantified. Tissue damage was evaluated by immunohistochemical and gene expression analyses. Since heme is one of the degraded products of red blood cells (RBCs) and damage-associated molecular pattern molecules (DAMPs), we examined the influence of heme on the pathology of SCI. Functional recovery was assessed using the open field motor score, a foot print analysis, a grid walk test, and a novel kinematic analysis system. Statistical analyses were performed using Wilcoxon's rank-sum test, Dunnett's test, and an ANOVA with the Tukey-Kramer post-hoc test. RESULTS: After SCI, the intralesional bleeding volume was correlated with the heme content and the demyelinated area at the lesion site, which were significantly reduced by the administration of TXA. In the injured spinal cord, toll-like receptor 4 (TLR4), which is a DAMP receptor, was predominantly expressed in microglial cells. Heme stimulation increased TLR4 and tumor necrosis factor (TNF) expression levels in primary microglial cells in a dose-dependent manner. Similarly to the in vitro experiments, the injection of non-lysed RBCs had little pathological influence on the spinal cord, whereas the injection of lysed RBCs or heme solution significantly upregulated the TLR4 and TNF expression in microglial cells. In TXA-treated SCI mice, the decreased expressions of TLR4 and TNF were observed at the lesion sites, accompanied by a significant reduction in the number of apoptotic cells and better functional recovery in comparison to saline-treated control mice. CONCLUSION: The administration of TXA ameliorated the intralesional cytotoxicity both by reducing the intralesional bleeding volume and preventing heme induction of the TLR4/TNF axis in the SCI lesion. Our findings suggest that TXA treatment may be a therapeutic option for acute-phase SCI..
8. Koji Imoto, Motoyuki Kohjima, Tomonobu Hioki, Tomoyuki Kurashige, Miho Kurokawa, Shigeki Tashiro, Hideo Suzuki, Akifumi Kuwano, Masatake Tanaka, Seiji Okada, Masaki Kato, Yoshihiro Ogawa, Clinical Features of Liver Injury Induced by Immune Checkpoint Inhibitors in Japanese Patients, Canadian Journal of Gastroenterology and Hepatology, 10.1155/2019/6391712, 2019, 2019.01, Aim. Immune checkpoint inhibitors (ICIs) have improved the survival rate of patients carrying various malignant neoplasms. Despite their efficacy, ICIs occasionally induce liver injury as an immune-related adverse event (irAE). This study aimed to reveal the clinical features of the hepatic irAE in Japanese patients. Methods. Among 387 patients treated with ICIs, those who developed drug-induced liver injury were investigated. We also describe the histological findings and clinical courses of four patients with hepatic irAE who underwent liver biopsy. Results. Among the 56 patients with all-grade liver injury, only 11 (19.6%) showed hepatocellular-type liver injury, which resembled autoimmune hepatitis. Thirty-four patients (60.7%) developed cholestatic or mixed-type liver injury, although only one patient showed abnormal image findings in the bile duct. Most patients with grade ≤2 liver injury improved spontaneously, while two patients with biliary dysfunction required ursodeoxycholic acid or prednisolone. Among eight patients with grade ≥3 liver injury, three required no immunosuppressants and five were treated with prednisolone (three of five patients required other types of immunosuppressants). Four patients in the case series showed diverse clinical features in terms of hepatotoxic pattern, symptoms, and the interval time between the initiation of immunotherapy and the onset of the hepatic irAE. Conclusions. Our findings suggest that ICIs could cause microscopic biliary disorder without any abnormal image finding. Because the hepatic irAE presents diverse clinical features, liver biopsy is recommended to provide appropriate treatments..
9. Junji Saruwatari, Chao Dong, Teruo Utsumi, Masatake Tanaka, Matthew McConnell, Yasuko Iwakiri, Integrated analysis of microRNA and mRNA expression profiles in splenomegaly induced by non-cirrhotic portal hypertension in rats., Scientific reports, 10.1038/s41598-018-36297-0, 8, 1, 17983-17983, 2018.12, The spleen plays an important role in the immune and hematopoietic systems. Splenomegaly is a frequent consequence of portal hypertension, but the underlying molecular and cellular mechanisms remain to be fully elucidated. In this study, we have performed a whole-genome microarray analysis combined with histological examination in enlarged spleens isolated from rats with partial portal vein ligation (PPVL) surgery to provide comprehensive profiles of microRNAs and their target mRNAs with a focus on their potential biological functions. A total of 964 mRNAs and 30 microRNAs showed significant differential expression in the spleens of PPVL rats compared to rats undergoing a sham procedure. Twenty-two down-regulated microRNAs were associated with significantly increased genes highly involved in fibrogenic activity and cell proliferation/migration (e.g., Ctgf, Serpine1, Col1a1). Consistently, histological analyses demonstrated increased splenic fibrosis and cell proliferation in the spleens of PPVL rats. Eight up-regulated microRNAs were associated with suppression of genes that are related to interferon-mediated antiviral activity in innate immune responses (e.g., Irf7, Dhx58). In conclusion, we determined a specific microRNA-mRNA network potentially implicated in the tissue fibrosis and cell proliferation in portal hypertension-induced splenomegaly. Our findings provide new insight into the mechanisms for regulation of spleen structure and function..
10. Masatake Tanaka, Yasuko Iwakiri, Lymphatics in the liver., Current opinion in immunology, 10.1016/j.coi.2018.04.028, 53, 137-142, 2018.08, The liver is the largest lymph producing organ. A significant increase in the number of hepatic lymphatic vessels, or lymphangiogenesis, has been reported in various liver diseases, including, but not limited to, cirrhosis, viral hepatitis and hepatocellular carcinoma. Despite its apparent relevance in healthy and diseased livers as these and other observations indicate, the hepatic lymphatic system has been poorly studied. With knowledge of the lymphatic system in other organs and tissues incorporated, this review article addresses the current knowledge of the hepatic lymphatic system and the potential role of lymphatic endothelial cells in the health and the disease of the liver and concludes with a brief description on future directions of the study of the hepatic lymphatic system..
11. Masatake Tanaka, Yasuko Iwakiri, The Hepatic Lymphatic Vascular System: Structure, Function, Markers, and Lymphangiogenesis., Cellular and molecular gastroenterology and hepatology, 10.1016/j.jcmgh.2016.09.002, 2, 6, 733-749, 2016.11, The lymphatic vascular system has been minimally explored in the liver despite its essential functions including maintenance of tissue fluid homeostasis. The discovery of specific markers for lymphatic endothelial cells has advanced the study of lymphatics by methods including imaging, cell isolation, and transgenic animal models and has resulted in rapid progress in lymphatic vascular research during the last decade. These studies have yielded concrete evidence that lymphatic vessel dysfunction plays an important role in the pathogenesis of many diseases. This article reviews the current knowledge of the structure, function, and markers of the hepatic lymphatic vascular system as well as factors associated with hepatic lymphangiogenesis and compares liver lymphatics with those in other tissues..
12. Kosuke Tanaka, Yuko Masaki, Masatake Tanaka, Masayuki Miyazaki, Munechika Enjoji, Makoto Nakamuta, Masaki Kato, Masatoshi Nomura, Toyoshi Inoguchi, Kazuhiro Kotoh, Ryoichi Takayanagi, Exenatide improves hepatic steatosis by enhancing lipid use in adipose tissue in nondiabetic rats., World journal of gastroenterology, 10.3748/wjg.v20.i10.2653, 20, 10, 2653-63, 2014.03, AIM: 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). METHODS: 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. RESULTS: 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(+)]. CONCLUSION: 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..
13. Masatake Tanaka, Kosuke Tanaka, Yuko Masaki, Masayuki Miyazaki, Masaki Kato, Kazuhiro Kotoh, Munechika Enjoji, Makoto Nakamuta, Ryoichi Takayanagi, Intrahepatic microcirculatory disorder, parenchymal hypoxia and NOX4 upregulation result in zonal differences in hepatocyte apoptosis following lipopolysaccharide- and D-galactosamine-induced acute liver failure in rats., International journal of molecular medicine, 10.3892/ijmm.2013.1573, 33, 2, 254-62, 2014.02, 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..
14. Shinichiro Takao, Kosuke Tanaka, Masayuki Miyazaki, Masatake Tanaka, Tomoko Ohashi, Masaki Kato, Kazuhiro Kotoh, Shinichi Aishima, Ryoichi Takayanagi, A case of fatal intrahepatic cholestasis with primary AL amyloidosis: is early diagnosis possible?, Clinical journal of gastroenterology, 10.1007/s12328-013-0406-x, 6, 5, 386-9, 2013.10, Immunoglobulin light chain-associated (AL) amyloidosis is a multisystemic disorder characterized by extracellular deposition of immunoglobulin light chain produced by a proliferative plasma cell clone. Although the liver is the major organ involved in AL amyloidosis, hepatic involvement is often clinically asymptomatic and severe intrahepatic cholestasis as the primary manifestation of the disease is rare. A 60-year-old man with severe jaundice, massive ascites and highly elevated alkaline phosphatase was diagnosed with AL amyloidosis by a transjugular liver biopsy. He had undergone a yearly medical check that showed no abnormalities except for mild elevation of serum γ-glutamyltransferase at 1 year before admission. Owing to his poor condition and rapidly progressive liver and renal dysfunction, neither stem cell transplantation nor a combination of chemotherapeutic agents could be applied, and he died 1.5 months after admission. An autopsy revealed amyloid deposition in the systemic organs, and there was no evidence of multiple myeloma. Continuous elevation of γ-glutamyltransferase may be a useful marker for early diagnosis of fatal hepatic amyloidosis..
15. Masatake Tanaka, Yuko Masaki, Kosuke Tanaka, Masayuki Miyazaki, Masaki Kato, Rie Sugimoto, Kazuhiko Nakamura, Shinichi Aishima, Ken Shirabe, Makoto Nakamuta, Munechika Enjoji, Kazuhiro Kotoh, Ryoichi Takayanagi, Reduction of fatty acid oxidation and responses to hypoxia correlate with the progression of de-differentiation in HCC., Molecular medicine reports, 10.3892/mmr.2012.1201, 7, 2, 365-70, 2013.02, The prognosis of patients with hepatocellular carcinoma (HCC) may be improved by novel treatments focusing on the characteristic metabolic changes of this disease. Therefore, we analyzed the biological interactions of metabolic features with the degree of tumor differentiation and the level of malignant potential in 41 patients with completely resectable HCC. The expression levels in resected samples of mRNAs encoded by genes related to tumor metabolism and metastasis were investigated, and the correlation between these expression levels and degrees of differentiation was analyzed. Of the 41 patients, 2 patients had grade I, 27 had grade II, and 12 had grade III tumors. Reductions in the levels of 3-hydroxyacyl-CoA dehydrogenase (HADHA) and acyl-CoA oxidase (ACOX)-2 mRNAs, and increases in pyruvate kinase isoenzyme type M2 (PKM2) mRNA were significantly correlated with the progression of de-differentiation. Analysis of partial correlation coefficients showed that the level of PKM2 mRNA expression was significantly correlated with those of pro-angiogenic genes, vascular endothelial growth factor (VEGF) and ETS-1. Moreover, the levels of VEGF-A and ETS-1 mRNA expression were independently correlated with that of the epithelial-mesenchymal transition (EMT)‑related gene SNAIL. These findings suggest that reductions in fatty acid oxidation and responses to hypoxia may affect the progression of malignant phenotypes in HCC..
16. Masayuki Miyazaki, Masaki Kato, Masatake Tanaka, Kosuke Tanaka, Shinichiro Takao, Motoyuki Kohjima, Tetsuhide Ito, Munechika Enjoji, Makoto Nakamuta, Kazuhiro Kotoh, Ryoichi Takayanagi, Antithrombin III injection via the portal vein suppresses liver damage., World journal of gastroenterology, 10.3748/wjg.v18.i16.1884, 18, 16, 1884-91, 2012.04, AIM: To investigate the effects of antithrombin III (AT III) injection via the portal vein in acute liver failure. METHODS: Thirty rats were intraperitoneally challenged with lipopolysaccharide (LPS) and D-galactosamine (GalN) and divided into three groups: a control group; a group injected with AT III via the tail vein; and a group injected with AT III via the portal vein. AT III (50 U/kg body weight) was administrated 1 h after challenge with LPS and GalN. Serum levels of inflammatory cytokines and fibrin degradation products, hepatic fibrin deposition, and hepatic mRNA expression of hypoxia-related genes were analyzed. RESULTS: Serum levels of alanine aminotransferase, tumor necrosis factor-α and interleukin-6 decreased significantly following portal vein AT III injection compared with tail vein injection, and control rats. Portal vein AT III injection reduced liver cell destruction and decreased hepatic fibrin deposition. This treatment also significantly reduced hepatic mRNA expression of lactate dehydrogenase and heme oxygenase-1. CONCLUSION: A clinically acceptable dose of AT III injection into the portal vein suppressed liver damage, probably through its enhanced anticoagulant and anti-inflammatory activities..
17. Masayuki Miyazaki, Masaki Kato, Kosuke Tanaka, Masatake Tanaka, Motoyuki Kohjima, Kazuhiko Nakamura, Munechika Enjoji, Makoto Nakamuta, Kazuhiro Kotoh, Ryoichi Takayanagi, Increased hepatic expression of dipeptidyl peptidase-4 in non-alcoholic fatty liver disease and its association with insulin resistance and glucose metabolism., Molecular medicine reports, 10.3892/mmr.2011.707, 5, 3, 729-33, 2012.03, Dipeptidyl peptidase-4 (DPP4) is a serine protease that degrades glucagon-like peptide-1 (GLP-1), an incretin hormone that stimulates insulin secretion from pancreatic β-cells. DPP4 is also involved in the regulation of T cell-mediated inflammatory processes. These properties of DPP4 suggest that it may play a role in the progression of non-alcoholic fatty liver disease (NAFLD). Hepatic DPP4 mRNA expression levels were analyzed by real-time PCR using liver biopsy samples from 17 NAFLD patients and 10 healthy subjects. In NAFLD patients, we also examined correlations between DPP4 expression levels and metabolic factors, including homeostasis model assessment-insulin resistance (HOMA-IR), body mass index (BMI), and serum cholesterol and triglyceride levels. To examine the potential effects of nutritional factors, DPP4 expression levels were analyzed in HepG2 cells subjected to various culture conditions. Hepatic DPP4 mRNA expression was significantly greater in NAFLD patients than in control subjects. DPP4 expression levels were negatively correlated with HOMA-IR and positively correlated with serum cholesterol levels. In HepG2 cells, high glucose significantly enhanced DPP4 expression, whereas insulin, fatty acids and cholesterol did not. Increased hepatic expression of DPP4 in NAFLD may be associated with metabolic factors, including insulin resistance, and may adversely affect glucose metabolism in this liver disease..
18. Masayuki Miyazaki, Masaki Kato, Masatake Tanaka, Kosuke Tanaka, Shinichiro Takao, Motoyuki Kohjima, Tetsuhide Ito, Munechika Enjoji, Makoto Nakamuta, Kazuhiro Kotoh, Ryoichi Takayanagi, Contrast-enhanced ultrasonography using Sonazoid to evaluate changes in hepatic hemodynamics in acute liver injury., Journal of gastroenterology and hepatology, 10.1111/j.1440-1746.2011.06790.x, 26, 12, 1749-56, 2011.12, BACKGROUND AND AIMS: Disturbances in hepatic microcirculation are believed to be involved in the mechanisms regulating the progression of acute liver injury (ALI). Evaluation of hepatic hemodynamics in patients with acute liver injury might be helpful in understanding the extent of the intrahepatic microcirculatory disturbances. Therefore, we investigated whether contrast-enhanced ultrasonography (CEUS) is useful to evaluate the changes in hepatic hemodynamics in patients with ALI. METHODS: CEUS was performed in 21 patients with ALI and coagulopathy. Participants were injected with 0.0075 mL Sonazoid/kg body weight, and time-intensity curves were simultaneously recorded for the hepatic and portal veins. The data were compared with those of 10 healthy volunteers. RESULTS: The arrival time of Sonazoid in the hepatic vein was similar to that in the portal vein in the patients, whereas the arrival time in the hepatic vein was delayed relative to that in the portal vain in the controls (interval between the hepatic and portal vein arrival times, control vs patients 6.74 ± 3.07 s vs 1.13 ± 1.07 s, P < 0.001). Repeated examination revealed that the interval between the hepatic and portal vein arrival times was extended by improvements in hepatic function. The early arrival of Sonazoid in the hepatic vein in the patients is likely to reflect the formation of intrahepatic shunts as a result of hepatic microcirculatory disturbances. CONCLUSION: CEUS using Sonazoid is a useful method to estimate the changes in hepatic hemodynamics in patients with ALI..
19. Nobito Higuchi, Masaki Kato, Masatake Tanaka, Masayuki Miyazaki, Shinichiro Takao, Motoyuki Kohjima, Kazuhiro Kotoh, Munechika Enjoji, Makoto Nakamuta, Ryoichi Takayanagi, Effects of insulin resistance and hepatic lipid accumulation on hepatic mRNA expression levels of apoB, MTP and L-FABP in non-alcoholic fatty liver disease., Experimental and therapeutic medicine, 10.3892/etm.2011.328, 2, 6, 1077-1081, 2011.11, Non-alcoholic fatty liver disease (NAFLD) is considered a hepatic manifestation of metabolic syndrome, which is known to be associated with insulin resistance (IR). NAFLD occurs when the rate of hepatic fatty acid uptake from plasma and de novo fatty acid synthesis is greater than the rate of fatty acid oxidation and excretion as very low-density lipoprotein (VLDL). To estimate the effects of IR on hepatic lipid excretion, mRNA expression levels of genes involved in VLDL assembly were analyzed in NAFLD liver. Twenty-two histologically proven NAFLD patients and 10 healthy control subjects were enrolled in this study. mRNA was extracted from liver biopsy samples and real-time PCR was performed to quantify the expression levels of apolipoprotein B (apoB), microsomal triglyceride transfer protein (MTP) and liver fatty-acid binding protein (L-FABP). Hepatic expression levels of the genes were compared between NAFLD patients and control subjects. In NAFLD patients, we also examined correlations between expression levels of the genes and metabolic factors, including IR, and the extent of obesity and hepatic lipid accumulation. Hepatic expression levels of apoB, MTP and L-FABP were significantly up-regulated in NAFLD patients compared to control subjects. The expression levels of MTP were correlated with those of apoB, but not with those of L-FABP. In the NAFLD liver, the expression levels of MTP were significantly reduced in patients with HOMA-IR >2.5. In addition, a significant reduction in MTP expression was observed in livers with advanced steatosis. Enhanced expression of genes involved in VLDL assembly may be promoted to release excess lipid from NAFLD livers. However, the progression of IR and hepatic steatosis may attenuate this compensatory process..
20. Masayuki Miyazaki, Masatake Tanaka, Akihiro Ueda, Tsuyoshi Yoshimoto, Masaki Kato, Makoto Nakamuta, Kazuhiro Kotoh, Ryoichi Takayanagi, Acute liver failure caused by drug-induced hypersensitivity syndrome associated with hyperferritinemia., World journal of gastroenterology, 10.3748/wjg.v17.i44.4928, 17, 44, 4928-31, 2011.11, Drug-induced hypersensitivity syndrome (DIHS) is a severe reaction usually characterized by fever, rash, and multiorgan failure, occurring 2-6 wk after drug introduction. It is an immune-mediated reaction involving macrophage and T-lymphocyte activation and cytokine release. A 54-year-old woman was diagnosed with rheumatic arthritis and initiated salazosulfapyridine by mouth. About 10 d later, she had a high fever, skin rash and liver dysfunction. She was admitted to hospital and diagnosed with a drug eruption. She was treated with oral prednisolone 30 mg/d; however, she developed high fever again and her blood tests showed acute liver failure and cytopenia associated with hyperferritinemia. She was diagnosed with acute liver failure and hemophagocytosis caused by DIHS. She was transferred to the Department of Medicine and Bioregulatory Science, Kyushu University, where she was treated with arterial steroid injection therapy. Following this treatment, her liver function improved and serum ferritin immediately decreased. We hypothesized that an immune-mediated reaction in DIHS may have generated over-activation of macrophages and T-lymphocytes, followed by a cytokine storm that affected various organs. The measurement of serum ferritin might be a useful marker of the severity of DIHS..
21. Kazuhiro Kotoh, Masaki Kato, Motoyuki Kohjima, Masatake Tanaka, Masayuki Miyazaki, Kazuhiko Nakamura, Munechika Enjoji, Makoto Nakamuta, Ryoichi Takayanagi, Lactate dehydrogenase production in hepatocytes is increased at an early stage of acute liver failure., Experimental and therapeutic medicine, 10.3892/etm.2011.197, 2, 2, 195-199, 2011.03, Although the mechanism involved in acute liver failure (ALF) has not yet been clarified, microcirculatory disturbance in the liver appears to play a pivotal role in the progression of this disease. To confirm the existence of hepatic hypoxic conditions, we evaluated the amounts of lactate dehydrogenase (LDH) in hepatocytes, since its production increases under low oxygen concentrations. Histological examination was performed in 7 patients with ALF. All 7 patients underwent a liver biopsy during the acute phase of ALF, and 4 of them underwent a second biopsy during the recovery phase. The obtained samples were immunohistochemically stained with anti-LDH5 and anti-CD-68 antibodies. As controls, we examined samples from patients with acute hepatitis, chronic hepatitis and liver cirrhosis. The production of LDH by hepatocytes and the number of CD-68 positive macrophages were markedly increased at the acute phase of ALF, and both of these effects abruptly decreased during the recovery phase. By contrast, most of the samples from the patients with chronic hepatitis and acute hepatitis showed slightly any increase in LDH staining. In cirrhotic patients, partially elevated LDH production was observed mainly around the central vein, but the staining intensity was less compared to that in ALF patients. Our findings indicate that hepatic hypoxic conditions exist in ALF at the acute phase and seem to closely correlate with macrophage overactivation in the liver. We speculate that microcirculatory disturbance may be a key process in the development and progression of ALF..
22. Nobito Higuchi, Masaki Kato, Masayuki Miyazaki, Masatake Tanaka, Motoyuki Kohjima, Tetsuhide Ito, Makoto Nakamuta, Munechika Enjoji, Kazuhiro Kotoh, Ryoichi Takayanagi, Potential role of branched-chain amino acids in glucose metabolism through the accelerated induction of the glucose-sensing apparatus in the liver., Journal of cellular biochemistry, 10.1002/jcb.22688, 112, 1, 30-8, 2011.01, Branched-chain amino acids (BCAAs) have a potential to improve glucose metabolism in cirrhotic patients; however, the contribution of liver in this process has not been clarified. To estimate the effect of BCAA on glucose metabolism in liver, we evaluated the mRNA expression levels of glucose-sensing apparatus genes in HepG2 cells and in rat liver after oral administration of BCAA. HepG2 cells were cultured in low glucose (100 mg/dl) or high glucose (400 mg/dl) in the absence or presence of BCAA. The mRNA expression levels and protein levels of GLUT2 and liver-type glucokinase (L-GK) were estimated using RT-PCR and immunoblotting. The expression levels of transcriptional factors, including SREBP-1c, ChREBP, PPAR-γm and LXRα, were estimated. The mRNA expression levels of transcriptional factors, glycogen synthase, and genes involved in gluconeogenesis were evaluated in rat liver at 3 h after the administration of BCAA. BCAA accelerated the expression of GLUT2 and L-GK in HepG2 cells in high glucose. Expression levels of ChREBP, SREBP-1c, and LXRα were also increased in this condition. BCAA administration enhanced the mRNA expression levels of L-GK, SREBP-1c, and LXRα and suppressed the expression levels of G-6-Pase in rat liver, without affecting the expression levels of glycogen synthase or serum glucose concentrations. BCAA administration enhanced the bioactivity of the glucose-sensing apparatus, probably via the activation of a transcriptional mechanism, suggesting that these amino acids may improve glucose metabolism through the accelerated utility of glucose and glucose-6-phosphate in the liver..
23. Masayuki Miyazaki, Nobito Higuchi, Masatake Tanaka, Akihiro Ueda, Shigeyuki Nagata, Toru Ikegami, Masaki Kato, Yuji Soejima, Akinobu Taketomi, Ryoichi Takayanagi, Living donor liver transplantation for acute liver failure caused by acute fatty liver of pregnancy, American Journal of Case Reports, 11, 126-129, 2010.11, Background: Acute fatty liver of pregnancy (AFLP) is a rare but serious maternal disease that occurs in the third trimester of pregnancy. Generally, prompt delivery can improve hepatic function, while delayed diagnosis and treatment of patients with AFLP could allow progression to acute liver failure. Case Report: A previously healthy 37-year-old woman presented to the clinic at 38 weeks gestation because of appetite loss and lower abdominal pain. Because her blood tests showed liver enzyme elevation, she was admitted to our hospital. She was diagnosed as having AFLP on the basis of clinical symptoms and laboratory data. She underwent an emergency caesarean section. Even after delivery, her condition worsened despite supportive care including plasma exchange and abdominal computed tomography (CT) showed atrophy of the liver. She underwent living donor liver transplantation on postpartum day 4. Histopathological findings were consistent with acute fatty liver of pregnancy. Conclusions: A small number of the patients with AFLP progress to fatal liver failure despite delivery of the fetus and aggressive supportive care. Liver transplantation is one treatment for acute liver failure caused by AFLP, and quantification of hepatic volume might be useful in prognostic prediction of the disease..
24. Masayuki Miyazaki, Masaki Kato, Masatake Tanaka, Ryoichi Takayanagi, High-density lipoprotein cholesterol improves the model for end-stage liver disease scoring system for prognostic prediction of acute liver failure., Scandinavian journal of gastroenterology, 10.3109/00365520903490614, 45, 4, 506-8, 2010.04.
25. Munechika Enjoji, Masatake Tanaka, Masayuki Miyazaki, Nobito Higuchi, Masaki Kato, Kazuhiro Kotoh, Kazuhisa Matsunaga, Takuya Nishinakagawa, Kazuyuki Machida, Manabu Nakashima, Makoto Nakamuta, Clinical effectiveness of ezetimibe for a non-obese patient with nonalcoholic fatty liver disease, American Journal of Case Reports, 10, 145-148, 2009.12, Background: We recently examined the distribution of abdominal fat, dietary intake and biochemical data in patients with nonalcoholic fatty liver disease (NAFLD) and compared these factors between nonobese and obese individuals. We found that non-obese NAFLD patients did not necessarily exhibit insulin resistance and/or dysregulated secretion of adipocytokines. However, the dietary cholesterol intake was superabundant and the dietary intake of polyunsaturated fatty acids was significantly lower in non-obese patients compared with obese patients, although total energy and carbohydrate intake was not excessive. Therefore, surplus cholesterol intake appears to be a factor associated with NAFLD development and liver injury. Case Report: In a non-obese 48-year-old male patient with NAFLD, in whom ursodeoxycholic acid and tocopherol acetate treatments were not effective, we tested a novel approach using the cholesterol absorption inhibitor ezetimibe. Without any dietary or exercise modification, 10 mg/day of ezetimibe was started instead of tocopherol acetate. Although body weight and body mass index remained nearly constant, the serum levels of transaminases promptly decreased into the normal range, which was accompanied by a decrease in serum total cholesterol and LDL-cholesterol exceeding 10%. Conclusions: Ezetimibe may offer a novel treatment for NAFLD, particularly in non-obese patients..
26. Makoto Nakamuta, Ryoko Yada, Tatsuya Fujino, Masayoshi Yada, Nobito Higuchi, Masatake Tanaka, Masayuki Miyazaki, Motoyuki Kohjima, Masaki Kato, Tsuyoshi Yoshimoto, Naohiko Harada, Akinobu Taketomi, Yoshihiko Maehara, Momoko Koga, Takuya Nishinakagawa, Manabu Nakashima, Kazuhiro Kotoh, Munechika Enjoji, Changes in the expression of cholesterol metabolism-associated genes in HCV-infected liver: a novel target for therapy?, International journal of molecular medicine, 10.3892/ijmm_00000299, 24, 6, 825-8, 2009.12, Recent investigations indicate that hepatitis C virus (HCV) infection is closely associated with hepatocytic lipid metabolism and induces hepatic steatosis. However, the actual lipid metabolism in HCV-infected liver has not been extensively investigated in humans. In this study, we evaluated the expression of lipid metabolism-associated genes in patients with HCV infection by real-time PCR. Sterol regulatory element-binding protein (SREBP)-2 expression was unchanged and low density lipoprotein receptor expression was markedly reduced by 90% in HCV-infected liver. The expression of apolipoprotein B100, microsomal triglyceride transfer protein and ATP-binding cassette G5 was significantly increased. Up-regulation of cholesterol synthesis-associated genes, including HMG-CoA reductase, HMG-CoA synthase, farnesyl-diphosphate synthase and squalene synthase, confirmed enhanced de novo cholesterol synthesis. The expression of cholesterol 7alpha-hydroxylase and farnesoid X receptor was enhanced, while bile salt export pump expression was unchanged. Fatty acid synthase expression was increased which was accompanied by increased expression of liver X receptor alpha and SREBP-1c. In summary, the regulation of lipid metabolism was impaired and cholesterol and fatty acid synthesis continued to increase without negative feedback in HCV-infected liver. These changes may be beneficial for HCV replication..
27. Masayuki Miyazaki, Nobito Higuchi, Masatake Tanaka, Akihiro Ueda, Masaki Kato, Yuji Tsuji, Kazuhiro Kotoh, Ryoichi Takyanagi, A case of breakthrough hepatitis caused by HBV-DNA mutations after 4 years combination therapy of Lamivudine and Adefovir dipivoxil, Acta Hepatologica Japonica, 10.2957/kanzo.50.514, 50, 9, 514-519, 2009.10, A 49-year-old man was admitted to our hospital suffering from acute hepatitis exacerbation caused by hepatitis B virus in July 2008. He had been diagnosed as chronic hepatitis B in 1999 and been successfully treated with lamivudine. In 2004, he experienced the first breakthrough hepatitis, which was controlled with an addition of adefovir dipivoxil to lamivudine. On admission, we found the elevation of the serum HBV-DNA level, which was revealed to contain the adefovir dipivoxil-resistant mutations: A181V/T and N236T. Although the appearance of mutations against adefovir dipivoxil has been described in some reports, it was rare that such mutations caused breakthrough hepatitis. We applied him the combination therapy with adefovir dipivoxil and entecavir, which decreased the serum HBV-DNA and alanine aminotransferase concentration within a month..
28. Nobito Higuchi, Masaki Kato, Yuki Shundo, Hirotaka Tajiri, Masatake Tanaka, Naoki Yamashita, Motoyuki Kohjima, Kazuhiro Kotoh, Makoto Nakamuta, Ryoichi Takayanagi, Munechika Enjoji, Liver X receptor in cooperation with SREBP-1c is a major lipid synthesis regulator in nonalcoholic fatty liver disease, Hepatology Research, 10.1111/j.1872-034X.2008.00382.x, 38, 11, 1122-1129, 2008.10, Aim: Nonalcoholic fatty liver disease (NAFLD) is one of the most frequent causes of liver dysfunction and its incidence has increased markedly. However, the mechanisms involved in the pathogenesis of NAFLD in humans have not been thoroughly investigated. Sterol regulatory element binding protein (SREBP)-1c and carbohydrate responsive element binding protein (ChREBP) are transcriptional factors that regulate the expression of lipogenic genes, including acetyl-CoA carboxylases (ACCs) and fatty acid synthase (FAS). SREBP-1c and ChREBP are transactivated by liver X receptor (LXR), a nuclear receptor that regulates the metabolism of cholesterol and fatty acids. To understand the mechanisms involved in the pathogenesis of NAFLD, we investigated the transcriptional factors and lipogenic genes activated in the liver with NAFLD. Methods: Real-time PCR was carried out on liver biopsy samples from 20 NAFLD patients. The target genes studied were: ACC1, FAS, SREBP-1c, ChREBP, AMP-activated protein kinase (AMPK), and LXRα. Results: LXRα, SREBP-1c, ACC1, and FAS were upregulated in NAFLD patients. Expression levels of LXR were four times greater than those of the controls and correlated significantly with SREBP-1c, but not with ChREBP, levels. Conclusions: These findings suggest that LXR acts as one of the main regulators of lipid metabolism by regulating SREBP-1c expression in NAFLD..