Shingo Iwata

Inhibition of tumor necrosis factor-induced apoptosis in transgenic mouse liver expressing creatine kinase

Abstract: Background: The mitochondrion acts as a pivotal decision center in many types of apoptotic responses. To clarify the effects of the enhanced mitochondrial function on tumor necrosis factorα (TNFα)‐induced apoptosis, we studied hepatic injuries in transgenic mice whose livers express creatine kinase (CK).

Diurnal Fluctuations of Arterial Ketone Body Ratio in Normal Subjects and Patients With Liver Dysfunction

To explore the metabolic aspects of chronic liver disease, diurnal changes of arterial ketone body ratio (acetoacetate/3-hydroxybutyrate), reflecting hepatic mitochondrial redox potential, were investigated in normal subjects, patients with chronic liver disease (Childs class A or B), and patients with hepatic failure (Childs class C). Ketone body ratio in normal subjects increased after breakfast from 0.96 to 2.00, after lunch from 2.17 to 2.38, and after dinner from 1.23 to 2.55 with blood glucose level ranging from 103 to 141 mg/dL (5.7 to 7.8 mmol/L). By contrast, the ketone body ratio in the Child A or B group changed little and remained within a range of 0.70-1.35 despite a large change in blood glucose level from 102 to 176 mg/dL (5.7 to 9.8 mmol/L). Ketone body ratio in Childs class C remained near or below 0.4 with no response to glucose administration, despite a marked elevation in blood glucose level. These results indicate that hepatic mitochondrial redox potential undergoes diurnal changes in sharp response to meals in normal liver function but that these fluctuations are absent in patients with liver damage (Childs class A, B, and C). Furthermore, it remains at low levels in severe liver failure (Childs class C). It is also suggested that hepatic mitochondrial redox potential plays an important role in the regulation of blood glucose levels.

Quantitative analysis of redox gradient within the rat liver acini by fluorescence images: effects of glucagon perfusion

The redox gradient along the sinusoid in the rat liver was studied using a redox scanner, a device based on tissue fluorescence scanning spectroscopy measuring the fluorescence signals of oxidized flavoprotein (FP) and reduced pyridine nucleotide (PN). The FP/(FP+PN) ratio reflects the mitochondrial redox state in the liver tissue. The distribution of mitochondrial redox state on the scanned area is expressed as two-dimensional gray-scale images with a 20 micron resolution. Using this instrument, we have scanned a 2.5 x 2.5 mm area of the frozen rat liver sample to investigate the redox gradient within acini and the effects of glucagon on the changes in the redox distribution. The redox images obtained in the perfused livers showed mosaic patterns implicating a regular heterogeneity of redox state in an acinus. The analysis of gradient curve, furthermore, clarified that the redox level in an acinus decreased sigmoidally from the periportal to the pericentral region. Glucagon, which has been reported to reduce the intracellular redox state, decreased the redox potential in whole acini, especially, in the periportal region, when compared with the perfusion without glucagon. These results strongly indicate an intraacinus heterogeneity of glucagon function, with glucagon selectively operating in the upstream of the sinusoid.

Effect of Gabexate Mesilate on Thrombin and Plasmin Generation after Hepatic Resection in Cirrhotic Patients

The effect of the gabexate mesilate (Gab) on thrombin and plasmin generation following liver resection in cirrhotic patients was studied. Six cirrhotic patients received an infusion of Gab after liver resection (Gab group), and another 6 patients did not receive such treatment (Con group). The parameters measured were thrombin-antithrombin complex (TAT), plasmin-antiplasmin complex (PAP) and D-dimer. The real increases of D-dimer and PAP were significantly higher in Con group after surgery while no significant difference was observed in the increase of TAT. These results show that Gab suppresses plasmin generation and following D-dimer production more effectively than thrombin generation after hepatic resection.

Preventive effect of a traditional herbal medicine, Hochu-ekki-to, on immunosuppression induced by surgical stress

PurposeTo examine the effect of preoperative administering of a Japanese traditional herbal medicine, Hochu-ekki-to (TJ-41), on immunosuppression induced by surgical stress in patients with gastrointestinal malignancies.MethodsTo monitor the immune functions, the mitochondrial membrane potential (MMP) and natural killer (NK) cell activity prior to and following operation were measured in peripheral blood lymphocytes (PBL) in patients with (n = 20) or without (n = 27) the preoperative administering of TJ-41 for 7 days. The plasma catecholamine and interleukin (IL)-6 levels were also analyzed prior to and following the operation.ResultsThe numbers of MMP-high CD56-positive cells (NK cells) and NK cell activities in the TJ-41-treated group were significantly higher than those in the control group (P = 0.026 and P = 0.037, respectively). An elevation of plasma noradrenaline and IL-6 following surgery was also inhibited by the preoperative administering of TJ-41 (P = 0.023 and P = 0.039, respectively). A positive correlation between MMP-high CD56-positive cell numbers and NK cell activity in PBL treated with carbonyl cyanide m-chlorophenyl hydrazone (CCCP) in vitro suggested that MMP measurement in CD56-positive cells can serve as a convenient alternative to evaluate the NK cell activity.ConclusionOur findings suggest that the preoperative administering of TJ-41 prevents surgical stress-induced immunosuppression by maintaining the NK cell activity and inhibiting the elevation of stress mediators.

Arterial ketone body ratio as a prognostic indicator in acute heart failure.

The arterial ketone body ratio (AKBR), an established clinical tool that reflects hepatic mitochondrial oxidation-reduction potential, predicts the outcome of patients with shock and multiple organ failure and the postoperative outcome in patients who have undergone major liver or heart surgery. The purpose of this study was to determine the prognostic significance of AKBR in patients with acute heart failure. The subjects of this study were 52 patients with acute heart failure. The following parameters were analyzed after Cox univariate hazard analysis was performed: AKBR, plasma norepinephrine, left ventricular ejection fraction, cardiac index, pulmonary arterial wedge pressure, sex, age, human atrial natriuretic peptide, endothelin-1, and cholesterol. The follow-up period was 30 weeks with cardiac death as the end point. Stepwise multivariate proportional hazard analysis revealed that AKBR was the most significant predictor of death, followed by norepinephrine and human atrial natriuretic peptide. Curve-fitting analysis revealed that the relationship between log (norepinephrine) and AKBR could best be described by two distinct lines, with their intersection at AKBR = 0.7 and norepinephrine = 418. With these results we conducted Kaplan-Meier analysis for AKBR > or = 0.7 and AKBR <0.7. The survival rate in patients with AKBR > or = 0.7 was 100%, whereas that in patients with AKBR <0.7 was 15% (p < 0.0001, log-rank analysis). These results indicate that AKBR is a novel independent predictor of death in heart failure.

A case of pediatric gastrointestinal stromal tumor of the stomach

A 16-year-old girl with an unremarkable past history presented with sudden dizziness. Patient height was 147 cm, and weight was 43 kg. White blood cell count, red blood cell count, Hgb, Hct, and Plt on blood count were 12600/ μ L, 168 × 10 4 / μ L, 5.3 g/dL, 15.6%, and 14.2 × 10 4 / μ L, respectively. The palpebral conjunctiva exhibited signs of anemia and the patient’s face was pale. Gastrointestinal bleeding was suggested and gastroendoscopic examination was performed. Numerous coagulations with acute bleeding were observed at the central concavity and a small ulcer was seen in the anterior wall of the lower stomach. There were no distinct gastroendoscopic characteristics when compared with other submucosal tumors. Moreover, whole body computed tomography (CT) and magnetic resonance imaging (MRI) showed a large mass in the stomach and revealed no apparent metastasis (Fig. 1). Preoperative differential diagnosis was leiomyosarcoma or malignant lymphoma. A malignant tumor was not considered because the neoplasm was nodular, the surface was smooth, and no typical ulcer formation was observed on gastroendoscopy. The tumor was removed by partial distal gastrectomy through minimal laparotomy and no liver or regional lymph node metastasis was noted. Postoperative course was uneventful, and radiotherapy and chemotherapy were not administered.

Quantitative PCR to evaluate small amounts of BCL2 mRNA in human peripheral T cells: implication of equimolar target and competitor end products.

BACKGROUND It is difficult to reliably and reproducibly quantitate small amounts of mRNA by conventional PCR. The method we describe here enabled us to more accurately quantitate a small amount of BCL2 mRNA in human peripheral T cells. METHODS The sample was amplified in four tubes containing three-fold serial dilutions of competitor so that when the PCR products in the four tubes were totaled, the number of target and competitor components were approximately equal. An unknown concentration of target molecules should be assessed only within a narrow range, requiring that several reactions be performed for each sample. RESULTS AND CONCLUSION With this method, conventional PCR machines can be used to perform quantitative PCR on very small amounts of BCL2, and would be especially useful for samples that contain substance(s) that affect PCR amplification efficiency.

Biochemical and biophysical alterations of lipoprotein after liver transplantation from a living related donor. A biochemical and proton NMR study.

Changes in lipoprotein metabolism after liver transplantation from living related donors were investigated in nine pediatric patients by means of biochemical and proton nuclear magnetic resonance (NMR) analyses of lipoprotein. NMR offers rapid and nondestructive measurement of lipoprotein. The ratio of esterified cholesterol to total cholesterol, expected to be a prognostic indicator after liver transplantation, was low before the operation (0.44) and recovered to over 0.6 at 3 weeks. The half line width of the methylene peak of lipoprotein, as measured by proton NMR, was correlated with the ratio of esterified cholesterol to total cholesterol. It is suggested that proton NMR analysis can provide information about the biophysical changes in lipoprotein associated with liver transplantation.

Decreased energy charge of peripheral blood lymphocytes in septic patients after hepatic resection.

We measured lymphocyte energy charge (LEC) in septic patients after hepatectomy to clarify the energy metabolism of lymphocytes in relation to arterial ketone body ratio (AKBR) reflecting the hepatic mitochondrial redox potential. Sixteen patients with AKBR above 0.7 (state A) tolerated their operations well without postoperative infectious episodes and their LEC (0.895 +/- 0.005, mean +/- SEM) was significantly (p < 0.001) higher than that (0.841 +/- 0.010) of 9 patients with AKBR from 0.7 to 0.4 (state B). Four of the 9 state B patients had multiple organ failure (MOF) with sepsis as a trigger. AKBR in 7 of 9 state B patients decreased and remained below 0.4 (state C). These state C patients showed significantly reduced LEC (0.781 +/- 0.024; p < 0.001, p < 0.05, compared with that in states A and B, respectively) and finally died of MOF with septic state. These results suggest that the severe and prolonged impairment of energy metabolism in the liver may be accompanied with the metabolic derangement of lymphocytes.