Ryuji Hirai

Attenuation of Liver and Lung Injury after Hepatic Ischemia and Reperfusion by a Cytokine-Suppressive Agent, FR167653

Background: Hepatic ischemia/reperfusion (I/R) injury is an important clinical problem and leads to the release of the proinflammatory cytokines, TNF-α and IL-1. These cytokines play important roles in the induction of polymorphonuclear neutrophil (PMN) activation and infiltration, and induce not only localized hepatic injury but also remote organ injury, especially pulmonary injury. Using a total hepatic ischemia model in rats, we tested our hypothesis that suppression of TNF-α and IL-1 by FR167653 ameliorates I/R injury in the liver and lung. Methods: Male Wistar rats, weighing 240–280 g, were divided into 3 groups, an FR group, a control group and a sham group. In the FR group, FR167653 (1 mg/kg/h) was administered continuously to the animals for 30 min prior to the onset of ischemia and for 2 h after reperfusion. The control group received normal saline. A porto-systemic shunt was placed between the cecal branch of the portal vein and the jugular vein, and total hepatic ischemia was produced for 90 min. The sham group was treated with placement of the porto-systemic shunt only. The 1-week survival rate, liver enzyme activity, hepatic tissue blood flow (HTBF), cytokine mRNA expression, myeloperoxidase (MPO) activity and histological results were studied. Results: The 1-week survival rate and HTBF were significantly higher in the FR group than in the control group. Serum AST, ALT, and LDH levels were significantly lower in the FR group at 30 min, 1 h and 3 h after reperfusion. MPO levels in liver and lung tissue were also significantly lower in the FR group. The expression of IL-1β mRNA remarkably decreased up to 6 h after reperfusion in the FR group. Conclusions: We concluded that the inflammatory cytokines, IL-1β, play important roles in hepatic I/R injury. FR167653 might ameliorate I/R injury and be useful in liver surgery with ischemia.

The Outcome of Gastrointestinal Stromal Tumors (GISTs) After a Surgical Resection in Our Institute

PurposeGastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract arising from Cajals cells and expressing c-kit. In a consensus report, the clinical behavior of GISTs was categorized into risk classes according to the tumor size and mitotic count. We analyzed the risk categories based on GIST patients who underwent a surgical resection at our institute during a period of 15 years.MethodsWe evaluated the risk categories of GISTs and analyzed the outcome and risk categories retrospectively. We presented the MIB-1 score of the tumor instead of mitotic counts for the evaluation of cellular growth because of inaccuracies regarding the mitotic counts.ResultsPatients were classified into 4 cases of very low risk, 11 of low risk, 8 of intermediate risk, and 5 of high risk. Four high-risk patients showed recurrence as either liver metastasis or peritoneal dissemination. In addition, local recurrence occurred in one low-risk and one intermediate-risk patient each.ConclusionOur cases confirmed the correlation between the risk categories and the prognosis. A complete resection with sufficient margin must be confirmed even in low-risk cases to prevent local recurrence. Since high-risk patients showed poor prognosis, the adjuvant treatment with chemotherapeutic regimens must therefore be further studied for high-risk patients.

Angiogenesis inhibitor TNP-470 can suppress hepatocellular carcinoma growth without retarding liver regeneration after partial hepatectomy.

AbstractPurpose. We investigated the suppressive effect of the angiogenesis inhibitor TNP-470 on accelerated hepatocellular carcinoma (HCC) growth in the regenerating liver. Methods. After 70% partial hepatectomy (PH), AH-130 cells were injected into the portal vein of Donryu rats. A control group was given the vehicle only, and the treated group was given 10 mg/kg TNP-470 subcutaneously every second day, from 24 h after tumor implantation, seven times. On day 14, tumor growth was evaluated by the number of foci on the liver surface, liver weight, and the microvessel density of the tumor. Results. The number of foci was significantly less in the treated group (116.5 ± 103.1) than in the control group (319.3 ± 223.1) (P ≪ 0.05), as was microvessel density, which was 31.3 ± 14.0/mm2 in the treated group and 61.2 ± 18.9/mm2 in the control group (P ≪ 0.05). The liver tended to weigh less in the treated group (12.15 ± 1.28 g) than in the control group (15.22 ± 5.35 g). We also assessed whether TNP-470 retards liver regeneration. Seven days after 70% PH, the liver weight in the treated group was similar to that in the control group. Total bilirubin, serum glutamic oxaloacetic transaminase, and serum glutamic pyruvic transaminase were not higher in the treated group than in the control group. Conclusion. TNP-470 can suppress HCC growth without retarding liver regeneration after PH.

Endothelin-1 levels in portal venous blood in relation to hepatic tissue microcirculation disturbance and hepatic cell injury after ischemia/reperfusion.

This study was conducted to clarify the role of endothelin-1 in the portal vein after hepatic ischemia/reperfusion and to ascertain whether it is related to hepatic microcirculation disturbance. Using a canine ischemic liver model, the portal and systemic endothelin-1 levels were measured before ischemia, then after 1h and 2h of reperfusion, and comparatively evaluated with the serum levels of GOT and lactic dehydrogenase (LDH). As an indicator of liver tissue microcirculation, tissue blood flow volume (TBF) was also measured in the site subjected to ischemia. The animals were divided into: group 1, which received ischemia for 30 min; group 2, which received ischemia for 60 min; and group 3, which received a sequence repeated four times of 15 min ischemia and 10 min reperfusion. The portal endothelin-1 level became significantly elevated after reperfusion compared to that before ischemia in all groups, being significantly higher in group 2 than in the other groups. The systemic endothelin-1 level also increased after reperfusion; significantly in group 2. The portal endothelin-1 level was generally higher than the systemic level, which again was statistically significant in group 2. After 2h of reperfusion, a significant positive correlation was found between the portal endothelin-1 level and serum LDH, whereas a significant negative correlation was found between the portal endothelin-1 level and TBF. The finding that the portal endothelin-1 level became elevated after hepatic ischemia/reperfusion suggests that it probably plays an essential role in hepatic ischemia/ reperfusion injury by adversely influencing tissue microcirculation.

Establishment of a human hepatoma cell line, HLE/2E1, suitable for detection of P450 2E1-related cytotoxicity

Abstract By transfection of an expression vector of human cytochrome P450 2E1 (CYP2E1) into a human hepatoma cell line (HLE), a new cell line (HLE/2E1) that stably expresses activity of CYP2E1 has been established. The HLE/2E1 cell line expressed a higher level of CYP2E1 messenger ribonucleic acid than did the mother HLE cell line. CYP2E1 enzyme activity determined by a p-nitrophenol oxidation assay was also higher in HLE/2E1 cells than in HLE cells. In addition, the enzyme activity of the HLE/2E1 cells was increased by ethanol treatment. Exposure to acetaminophen (APAP) or buthionine sulfoximine (BSO) caused a greater decrease in viability of the HLE/2E1 cells than that of the HLE cells, as determined by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay. The cytotoxicity of APAP or BSO to HLE/2E1 cells was inhibited by the addition of ethanol or vitamin E. However, the cytotoxicity of both APAP and BSO was enhanced by 24-h preincubation of HLE/2E1 cells with ethanol. These results show that this cell line provides a useful model for studying catalytic properties of CYP2E1 and cytotoxic mechanisms of chemicals metabolized by CYP2E1.

Experimental Evaluation of the Effects of the Intraportal Administration of Cyclic Guanosine Monophosphate on Ischemia / Reperfusion in the Porcine Liver

This study was done to examine the protective effects of cyclic guanosine monophosphate (cGMP), a second messenger of nitric oxide, for ischemia/reperfusion injury of the liver, since it is known to induce vasodilatation and to inhibit platelet aggregation. Using an experimental model of porcine liver ischemia, 8-bromoguanosine 3′,5′ monophosphate, a cGMP analog, was continuously administered into the portal vein before ischemia and after reperfusion 30 min for each in the cGMP group (n=6). Saline water was administered in the same way in the control group (n=6). The cardiac output (CO), mean arterial blood pressure (MAP), portal venous flow (PVF), hepatic arterial flow (HAF), hepatic tissue blood flow (HTBF), and hepatic tissue cGMP level were determined. Hepatic enzymes and the bile discharge were also assessed as indicators of hepatic function. The hepatic tissue cGMP level was significantly higher, and PVF, HTBF, and the bile discharge were significantly greater in the cGMP group, while there were no remarkable differences between the groups with CO, MAP, HAF, and hepatic enzymes. In conclusion, the continuous supplementation of cGMP into the portal vein was found to be beneficial for preserving both the hepatic circulation and, consequently, the hepatic function of after warm ischemia of porcine liver.

A Case of Quadruple Cancer with Metachronous Colon Cancer -A Case of Operation for Synchronous Triple Cancer-

重複癌の報告は近年増加しており, 要因の1つに診断機器・技術の向上が考えられる. 今回われわれは, 異時性大腸癌を含む同時性胃癌, 十二指腸癌, 腎癌の4重複癌を経験し, 同時性3重複癌に対し1期的手術を施行した. 平成7年1月S状結腸の上皮内癌に対し, 内視鏡的大腸ポリープ切除術を施行した. 平成12年8月汎発性腹膜炎で緊急手術をした際, 胃癌の穿孔が疑われ, 術後に上部消化管内視鏡検査を施行したところ, 胃癌, 十二指腸癌を発見した. また腹部CTで右腎癌の診断を得て, 平成12年9月胃全摘術・膵頭十二指腸切除術・右腎摘出術を施行した. 病理学的にも3重複癌であったが, 本症例の4重複癌はいずれも根治的に治療できた. 文献上4重複癌の報告は年ごとに増加し, 同時多発癌の報告頻度も近年増加している. 特に共通の危険因子を持つ癌は重複しやすいと考えられ, 今日では重複癌の発生にも注意し診療することが必要と思われた.