Katsutaka Mori

Inhibition of stress-induced gastric injury in the rat by glutathione

Glutathione metabolism occurs via interorgan cycles in which hepatic synthesis of reduced glutathione and its transfer to extrahepatic tissues play an important role. To elucidate the physiologic significance of the cycles and tissue thiol status during stress-induced gastric mucosal injury, dynamic aspects of glutathione metabolism were analyzed in rats that were treated with water-immersion restraint. This treatment induced gastric mucosal lesion with concomitant decrease in the levels of perchloric acid-soluble thiols in various tissues, particularly in the liver and stomach. During the treatment, glutathione levels markedly decreased in the liver but not in other tissues. Depletion of hepatic glutathione by buthionine sulfoximine, a specific inhibitor for gamma-glutamyl cysteine synthetase, markedly decreased hepatic glutathione levels and increased the gastric injury. Intraperitoneal injection of reduced glutathione significantly increased plasma levels of glutathione and inhibited the occurrence of gastric injury without affecting intracellular glutathione levels. These results indicate that extracellular glutathione and its interorgan metabolism might play a critical role in the protection of gastric mucosa particularly when animals were challenged with various stress.

Clinical Significance of Serum CA125 Values in Patients with Cancers of the Digestive System

A study of 347 patients with gastrointestinal diseases revealed elevation of CA125 in sera of 63% of patients with pancreatic carcinoma, 46% of patients with carcinoma of the biliary tract, 40% of patients with liver carcinoma and 11–37% of patients with other carcinomas. All of the patients with acute pancreatitis, chronic pancreatitis, cholelithiasis, and peptic ulcer had normal CA125 values, but 35% of patients with liver cirrhosis and 10% of patients with chronic active hepatitis had elevated values. Patients with disseminated carcinomas had significantly higher levels than patients with localized carcinomas. CA125 did not significantly correlate with CA19–9 or carcino-embryonic antigen in patients with pancreatic carcinoma. Ninety-seven percent of patients with pancreatic carcinoma were defined as being positive when both serum CA125 and CA19–9 were evaluated. These results indicate that CA125 is useful for differentiating pancreatic carcinoma from chronic pancreatitis, especially when supplemented with CA19–9.

The role of tumor necrosis factor-α in the aggravation of cerulein-induced pancreatitis in rats.

SummarySevere acute pancreatitis is often complicated by intraperitoneal infection, resulting in multiple organ failure (MOF). It is known to elevate serum tumor necrosis factor (TNF-α) in patients with sepsis and/or MOF. In order to study the role of TNF-α in the aggravation of acute pancreatitis, we investigated TNF-α production by peritoneal macrophages in acute pancreatitis rat using the cerulein-induced pancreatitis model. TNF-α production by isolated peritoneal macrophages following lipopolysaccharide (LPS) stimulation was significantly increased in pancreatitis rats as compared with nonpancreatitis control rats (p<0.001). Serum TNF-α activity was elevated following intraperitoneal administration of LPS as the septic challenge both in pancreatitis rats and in control rats, being significantly higher in the former (p<0.05). Histological findings and liver function tests revealed that LPS induced more severe liver damage in pancreatitis rats than in control rats within 24 h after LPS administration. These results indicate that increased TNF-α production by peritoneal macrophages in acute pancreatitis augmented LPS-induced liver injury and suggest the possibility that TNF-α may play a role in the development of MOF during acute pancreatitis complicated by intraabdominal sepsis.

Immunosuppressants Decrease Neutrophil Chemoattractant and Attenuate Ischemia/Reperfusion Injury of the Liver in Rats

BACKGROUND Neutrophils may play an important role in the development of liver ischemia/reperfusion injury. We investigated the effects of the immunosuppressants azathioprine (AZA), cyclosporine A (CsA), tacrolimus (FK506), and rapamycin (RPM) on the expression of cytokine-induced neutrophil chemoattractant (CINC) after ischemia/reperfusion of the liver. METHODS Liver ischemia was induced in male Wistar rats by occluding the portal vein with a microvascular clip for 30 minutes. Rats received two intramuscular injections of AZA (4 mg/kg), CsA (5 mg/kg), FK506 (0.5 mg/kg), or RPM (0.5 mg/kg) 3 and 24 hours before ischemia/reperfusion of the liver. RESULTS Serum CINC concentrations in untreated animals increased, peaked 6 hours after reperfusion, and thereafter decreased gradually. Pretreatment with AZA, CsA, FK506, and RPM, however, inhibited the increase in serum CINC concentrations after reperfusion. CINC mRNA in liver tissue increased and peaked 3 hours after reperfusion, but was significantly lower in animals treated with AZA, CsA, FK506, and RPM. In vitro CINC production by Kupffer cells harvested from animals treated with AZA, CsA, FK506, or RPM 3 hours after reperfusion was also significantly lower than that observed in untreated animals. Both myeloperoxidase activity and the number of neutrophils accumulating in the liver 24 hours after reperfusion in animals treated with AZA, CsA, FK506, and RPM were significantly lower than in untreated animals. This correlated with lower serum aspartate transaminase, alanine transaminase, and lactate dehydrogenase levels in animals treated with AZA, CsA, FK506, and RPM 24 hours after reperfusion. CONCLUSION The immunosuppressants AZA, CsA, FK506, and RPM reduce neutrophil accumulation and attenuate ischemia/reperfusion injury of the liver.

A new approach to chemoembolization for unresectable hepatocellular carcinoma using aclarubicin microspheres in combination with cisplatin suspended in iodized oil

Sixty‐six consecutive patients with unresectable hepatocellular carcinoma (HCC) were treated with transcatheter arterial chemoembolization (TACE) using aclarubicin microspheres (ACRms) in combination with cisplatin suspended in iodized oil (Lipiodol, Laboratoire Guerbert, Paris, France) (CSL). The stages of the disease were as follows: Stage I (n = 1), Stage II (n = 10), Stage III (n = 26), and Stage IV (n = 29). The effectiveness of TACE was assessed by comparing ACRms with CSL with ACRms without CSL. Of 66 patients treated with ACRms and CSL, 62 (93.9%) could be examined for response. According to response criteria, there were 31 (50.0%) partial responses and 17 (27.4%) minor responses. In 13 cases (21.0%) there was no change and in 1 case (1.6%) there was progressive disease. The cumulative survival rate was 80.7% at 1 year, 64.2% at 2 years, and 50.6% at 3 years. The rates were significantly higher than those of the group treated with ACRms. Eleven patients in the ACRms and CSL group experienced clinical complications: cholecystitis (4.5%), pancreatitis (3.0%), liver abscess (3.0%), hepatic failure (3.0%), gastrointestinal bleeding (1.5%), and renal failure (1.5%). No lethal side effects related to the therapy were observed. TACE using ACRms in combination with CSL prolongs the survival of patients with unresectable HCC. Cancer 68:2555–2560, 1991.

Anticoagulant pretreatment attenuates production of cytokine-induced neutrophil chemoattractant following ischemia-reperfusion of rat liver

We investigated whether anticoagulation would diminish ischemia-reperfusion injury of the liver. Liver ischemia was induced in rats by occluding the portal vein for 30 min. Anticoagulant was injected intravenously 10 min before occlusion. Serum concentrations of cytokine-induced neutrophil chemoattractant (CINC) in untreated rats increased following reperfusion, reaching a peak at 6 hr, then decreasing gradually to control levels by 24 hr. CINC levels in rats pretreated with heparin (50 units/kg), AT-III (250 units/kg), or DEGR-Xa (10 mg/kg) peaked at 3 hr after reperfusion and declined to baseline within 12 hr; peak CINC values were significantly lower than in untreated control rats. Expression of CINC mRNA in liver tissue paralleled the CINC serum levels. Both myeloperoxidase activity and the number of neutrophils in the liver were decreased in the anticoagulant groups. In addition, significant correlations were observed between the maximum values of AST, ALT, and LDH versus the peak CINC levels following ischemia-reperfusion. These results indicate that the release of CINC after ischemia-reperfusion of the liver is mediated by activation of coagulation within the hepatic microcirculation.

Neutrophil elastase and oxygen radicals enhance monocyte chemoattractant protein- expression after ischemia/reperfusion in rat liver.

BACKGROUND The monocyte chemoattractant protein-1 (MCP-1) is produced during reperfusion injury and induces tissue factor that is the initiator of the clotting cascade. Neutrophil elastase is a crucial mediator of inflammatory tissue damage. Activation of the coagulation system stimulates cytokine production by activated leukocytes. We investigated the effects of neutrophil elastase and oxygen radicals generated by hypoxia associated with microthrombus formation on MCP-1 expression after ischemia/reperfusion in rat liver. METHODS In vitro MCP-1 production by macrophages after stimulation with human neutrophil elastase (HNE) or oxygen radicals generated by hypoxanthine and xanthine oxidase was examined. Liver ischemia was induced in rats by occluding the portal vein for 30 min. An inhibitor of human neutrophil elastase (ONO-5046*Na, 10 mg/kg) and antithrombin III (AT-III, 250 U/kg) were injected i.v. 5 min before vascular clamping. Serum concentrations of MCP-1 were measured by enzyme-linked immunosorbent assay. RESULTS Human neutrophil elastase or oxygen radicals significantly enhanced in vitro MCP-1 production by macrophage. Serum MCP-1 concentrations reached a peak at 6 hr after reperfusion and then gradually decreased. However, pretreatment of animals with AT-III or ONO-5046*Na alone resulted in significantly smaller increases in serum concentrations of MCP-1 after reperfusion. Pretreatment with both ONO-5046*Na and AT-III produced additive effects. The combined treatment with ONO-5046*Na and AT-III significantly reduced MCP-1 mRNA in liver after ischemia/reperfusion. CONCLUSIONS MCP-1 production by macrophages is stimulated by neutrophil elastase and oxygen radicals generated by hypoxia, probably due to microthrombus formation after ischemia/reperfusion of the rat liver.

Variable Allograft Responses To Pretreatment With Donor Splenocytes Treated With Mitomycin C In The Rat

In an attempt to investigate the nonspecificity of the effect of administration of donor splenocytes treated with mitomycin C (MMC) 7 days before transplantation in inducing immunological unresponsiveness, the survival rates of liver, heart, small bowel, and skin allografts were compared in the RT1-incompatible ACI(RT1a) to LEW(RT1l) rat combination. ACI donor splenocytes (3 x 10(6)) treated with MMC were administered i.p. or i.v. via the penile vein 7 days before transplantation. Both routes of administration prolonged the survival of hepatic allografts (greater than 87.2 +/- 22.2 days and greater than 78.9 +/- 28.2 days, respectively), compared with controls (10.6 +/- 0.5 days). Cardiac allograft survival in untreated controls was 6.0 +/- 0.4 days. A single i.v. injection of 3 x 10(6) donor splenocytes resulted in significantly prolonged survival (10.0 +/- 4.3 days), whereas i.p. injection showed rejection at a mean of 6.0 +/- 1.2 days. A single i.p. injection of 3 x 10(6) splenocytes did not increase survival of small bowel allografts (10.3 +/- 4.8 days), compared with controls (8.8 +/- 1.8 days). On the other hand, a single i.v. injection of donor splenocytes prior to transplantation significantly prolonged survival of small bowel allografts (13.4 +/- 3.5 days). No signs of graft-versus-host reaction (GVHR) were observed during these experiments. Neither a single i.p. nor a single i.v. injection of donor splenocytes resulted in prolonged survival of ACI-to-LEW skin allografts (6.3 +/- 0.8 days and 6.6 +/- 0.9 days, respectively), compared with controls (5.7 +/- 0.5 days). Interestingly, we confirmed the relative ease with which survival of hepatic allografts can be prolonged in the rat by donor antigen treatment alone, even in a strongly rejecting RT1-incompatible rat strain combination, in contrast to other organ allografts such as heart, small intestine, and skin. The discrepancy in survival of different organ allografts following pretreatment with donor splenocytes treated with MMC may be explained by a difference in the immunogenicity of the organs transplanted or other factors.

Neutrophil elastase enhances intercellular adhesion molecule-1 expression

BACKGROUND Elastase released from activated neutrophils is an important mediator of inflammatory tissue damage. We investigated the effect of human neutrophil elastase (NE) inhibitor (ONO-5046) on reperfusion injury after pancreaticoduodenal transplantation in rats by measuring the expression of intercellular adhesion molecule-1 (ICAM-1). Additional in vitro experiments were conducted to investigate the effect of NE on ICAM-1 mRNA transcription in a rat endothelial cell line (WK-5) and human umbilical vein endothelial cells (HUVEC). METHODS In an in vivo experiment, male Wistar rats were transplanted with syngeneic pancreaticoduodenal grafts. An NE inhibitor, ONO-5046, was injected intravenously 5 min before vascular clamping and immediately after reperfusion at a dose of 10 mg/kg. ICAM-1 expression was determined by immunostaining and Northern analysis. In in vitro experiments, the effects of NE and chemical agents on ICAM-1 mRNA transcripts were determined in WK-5 cells and HUVEC. RESULTS Pretreatment with ONO-5046 decreased ICAM-1 immunostaining in the pancreatic graft and inhibited the increase in ICAM-1 mRNA levels in grafts after reperfusion. ICAM-1 mRNA levels in WK-5 cells and HUVEC showed stimulation by NE, while ONO-5046 inhibited this increase. Calcium ionophore (A23187) augmented NE stimulation of ICAM-1 mRNA levels in these cells. In contrast, a phospholipase C inhibitor (U73122) blunted NE induction of ICAM-1 mRNA, and either calcium chelator (TMB-8) or a nuclear factor-kappa B inhibitor (pyrrolidine dithiocarbamate) completely inhibited induction. CONCLUSION These results indicate that NE stimulates ICAM-1 expression in pancreatic grafts via intracellular Ca2+ influx and a phospholipase C signal transduction.

Intrahepatic Ramification of the Portal Vein in the Right and Caudate Lobes of the Liver

We defined the subsegmental divisions and the ramification patterns of the portal vein in the right and caudate lobes using 25 human liver casts. The ramifications of the portal vein and the subdivisions of the liver were classified based on the major portal veins with the largest diameter and those having a diameter of not less than two thirds of the largest vein in each subsegment. The following results were obtained. (1) The portal trunk showed three ramification patterns and the basic pattern was bifurcation (80%). (2) The anterior portal vein first ramified into several anterior-inferior portal veins (P5) and ran toward the superior direction to bifurcate into 2 major portal veins in the anterior-superior subsegment (S8). (3) There were three types of ramification patterns of the portal veins in S8: bifurcation (84%), trifurcation and one-pedicle type. (4) There were also three branching types of the largest vein (P5-max) in P5: ramification from the anterior portal vein, P8-anterior vein supplying the anterior region of S8 and P8-posterior vein supplying the posterior region of S8. (5) The posterior portal vein showed two ramification patterns of the bifurcation (36%) and nonbifurcation type. (6) The major portal veins in the caudate subsegment ramified at various sites such as the portal trunk, left, right and/or other portal veins.