Suzuki's Criteria Research Articles

Hemodynamic contribution of transdural collateral flow in adult patients with moyamoya disease.

To evaluate the hemodynamic contributions of collateral flow in adult patients with moyamoya disease, neurological deterioration or fluctuation during admission, Suzuki grade, various collateral routes, lesion volume, cerebral blood flow (CBF), and their associations were analyzed. Thirty patients (60 cerebral hemispheres, mean age 45±25years, and 73.3% female) who were diagnosed with moyamoya disease or syndrome were enrolled over 3years. Moyamoya stages from each hemisphere were stratified according to the Suzuki's criteria through six-vessel angiography into internal carotid arteries (ICAs), external carotid arteries (ECAs), and vertebral arteries (VAs). Collateral routes were categorized into the circle of Willis, leptomeningeal, and transdural. The volume of ipsilateral infarction was analyzed by magnetic resonance imaging. CBF volume was measured using color-coded duplex sonography. Suzuki's grade was inversely correlated with flow volume of the ICAs (p<0.001), whereas no association was found with that of the ECAs (p=0.445) or VAs (p=0.096). Among hemispheres with≥grade 3 (n=36), patients with transdural ECA collateral flow had less neurological deterioration or fluctuation (0.0 vs. 30.8%, p=0.047), smaller lesion volume (2.4±3.6 vs. 27.6±59.3mL, p=0.041), lower ICA flow (88.4±45.9 vs. 146.2±121.7mL/min, p=0.022), higher ECA flow (205.7±77.7 vs. 135.9±52.7mL/min, p=0.046), and a higher ECA/ICA flow volume ratio (31.8±92.8 vs. 1.7±1.9, p=0.024). Our results suggest that ICA flow volume is inversely correlated with Suzuki grade, and that transdural ECA collaterals appear to be an important detour in adult patients with advanced stage moyamoya disease, suggesting a protector against an impending ischemic attack.

Minocycline protects against hepatic ischemia/reperfusion injury in a rat model.

Hepatic ischemia/reperfusion (I/R) injury is a common clinical problem. The present study was conducted to investigate the protective effect and mechanism of minocycline (Mino), a tetracycline with anti-inflammatory and antioxidant properties, on I/R injury of liver in rats. In total, 54 male Sprague-Dawley rats were randomly divided into 3 groups with 18 rats in each: Sham-operated (control group), I/R model (I/R group) and Mino preconditioning groups (Mino group). The rats of the Mino group were administered Mino (45 mg/kg) by gastric irrigation at 36 h before surgery and were subsequently administered with 22.5 mg/kg every 12 h for the 36 h before surgery. The rats were sacrificed at 2, 6 and 24 h after reperfusion, and the serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) were measured. Hematoxylin/eosin staining of liver tissues was performed to detect the rat liver histological changes and the grade of liver I/R injury (Suzuki's criteria); the levels of malondialdehyde (MDA) and myeloperoxidase (MPO) were determined by spectrophotometry; hepatic tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) mRNA were measured by quantitative polymerase chain reaction; the Dickkopf-1 (DKK-1) and β-catenin gene products of the liver were detected by western blot analysis. Mino treatment significantly ameliorated the I/R injury of the liver, as shown by decreased Suzuki scores and liver function (ALT, AST and LDH). After 2, 6 and 24 h reperfusion, compared to the I/R group the MDA and MPO levels of the Mino group decreased in the liver tissues and the levels of hepatic TNF-α and IL-1β mRNA were decreased too. The protein expression of hepatic DKK-1 decreased, whereas β-catenin increased, which indicates that the Wnt/β-catenin pathway has been activated. In conclusion, Mino protects the liver from I/R injury mainly through reducing oxidative stress and inhibiting the release of pro-inflammatory cytokines by activating the Wnt/β-catenin signaling pathway in the liver.

Mast cell degranulation promotes ischemia–reperfusion injury in rat liver

BackgroundMast cells (MCs) play a role in ischemia–reperfusion (I/R) injury in many organs. However, a recent study found that MCs are not involved in I/R injury in isolated rat livers that were perfused only for 1 h. The purpose of this study is to reevaluate the role of MCs in hepatic I/R injury in rat. Materials and methodsA warm hepatic I/R injury model of 1 h ischemia followed by 24 h of reperfusion was used. MC modulation was induced via cromolyn injection or a method called MC depletion using compound 48/80. The effects of MC modulation were evaluated by toluidine blue staining and assessment of mast cell tryptase in sera. The role of MCs in I/R injury was evaluated by hematoxylin and eosin staining graded by Suzuki criteria, alanine aminotransferase and aspartate aminotransferase levels in sera, and malondialdehyde levels in liver homogenates. ResultsFirst, MC degranulation peaked after 2 h of reperfusion and liver damage peaked after approximately 6 h of reperfusion. Second, a method called MC depletion previously used in the skin with repeated injections of compound 48/80 worked similarly in the hepatic setting. Third, stabilization of MCs with cromolyn or depletion of MCs with compound 48/80 each decreased hepatic I/R injury. The most noticeable effects of cromolyn and compound 48/80 treatment were observed after approximately 6 h of reperfusion. ConclusionsMC degranulation promotes hepatic I/R injury in rats.

Pretreatment with intrathecal or intravenous morphine attenuates hepatic ischaemia–reperfusion injury in normal and cirrhotic rat liver

Opioids have been shown to attenuate ischaemia-reperfusion injury (IRI) in a number of organs. We evaluated the effect of morphine pretreatment on IRI in both normal and cirrhotic rat liver. Morphine was administered either i.v. or intrathecally (i.t.) 10 min before initiating 1 h of ischaemia followed by 6 h reperfusion in normal rat liver. Hepatic injury was assessed histologically using Suzuki's criteria. These manoeuvres were repeated using the optimal dose of morphine after administration of naloxone methiodide and wortmannin. Serum levels of transaminases were measured, and expression of phosphorylated Akt, Jak2, and STAT3 were assessed by immunoblotting. Similar procedures were repeated on rats with carbon tetrachloride-induced liver cirrhosis, and the levels of phosphorylated protein kinase C (PKC), haem oxygenase-1 (HO-1), and inducible nitric oxide synthase (iNOS) were also evaluated, as these proteins have beneficial effects during IRI. Morphine pretreatment at 100 µg kg(-1) (i.v.) or 10 µg (i.t.) reduced necrosis, apoptosis, and serum transaminase levels, and increased phosphorylated Akt and STAT3 but not JAK2 expression in normal liver. These changes were reversed by prior administration of naloxone methiodide and wortmannin. Although morphine preconditioning was also protective in cirrhotic liver, STAT3 and JAK2 phosphorylation status was unchanged. There was, however, increased expression of phosphorylated PKC and HO-1, and a reduction in iNOS. Morphine preconditioning protects against IRI in both normal and cirrhotic rat liver. This involves opioid receptors, phosphatidylinositol-3-kinase, and Akt. The downstream pathways involved are different for cirrhotic liver, with preliminary evidence suggesting involvement of HO-1.

Effect of methylene chloride upon hepatic ischemic reperfusion injury

To investigate the effects and mechanisms of methylene chloride (MC) in hepatic ischemic reperfusion injury. Eighty SD-rats were divided equally into 4 groups: control group (n = 20), donors without any treatment; CoPP group (n = 20), donors injected with CoPP (5 mg/kg, ip) at 24 h; ZnPP group (n = 20), donors injected with ZnPP (20 mg/kg, ip) at 24 h; MC group (n = 20), donors fed with MC (500 mg/kg) per day for 7 days before graft procurement. Syngeneic orthotopic liver transplantation was performed in rats with modified Kamada's two-cuff technique. And SD rats were used as donors (n = 10)and recipients respectively. 5 recipients in each group were sacrificed and the grafts were procured at day 3 after transplantation, the post-operative survival time was observed in the remnant. The tests were determined as following: the level of serum ALT, AST in recipients; heme oxygenase-1 (HO-1) expression of graft was tested by immunohistochemistry and Western blot; the index of graft apoptosis examined by TUNEL method; the pathology of graft assessed by Suzuki's criteria. The level of serum ALT [(65 +/- 28) U/L], AST [(187 +/- 43) U/L] in CoPP and ALT [(75 +/- 16) U/L], AST [(185 +/- 42) U/L] in MC group was significantly lower than that ALT [(346 +/- 45) U/L], AST [(474 +/- 90) U/L] in control group and ALT [(578 +/- 75) U/L], AST [(1084 +/- 128) U/L] in ZnPP group (P < 0.01). The median expression of HO-1 in MC group was no significantly different with that in control group (P > 0.05). While the median expression of HO-1 in CoPP group was higher than that in control group (P < 0.05). The index of graft apoptosis in MC group and CoPP group, 4.1% +/- 0.6% and 3.2% +/- 0.8% respectively, was significantly lower than that (12.5% +/- 2.4%) in control group and (25.8% +/- 3.1%) in ZnPP group (P < 0.05). Compared with the other two groups, MC and CoPP groups had lesser neutrophil infiltration and a lower grade of hepatocytic injury in grafts. Suzuki's scores in grafts of MC and CoPP groups were lower than that in control and ZnPP groups (P < 0.05). The median post-transplantation survival time of the recipients in MC and CoPP groups was 100 and 93 days respectively while that in control and ZnPP groups was 85 and 12 days (P < 0.05). Over-expression of HO-1 and MC both have protective effects in hepatic ischemic reperfusion injury.

Vascular Endothelial Growth Factor Antagonist Modulates Leukocyte Trafficking and Protects Mouse Livers against Ischemia/Reperfusion Injury

Although hypoxia stimulates the expression of vascular endothelial growth factor (VEGF), little is known of the role or mechanism by which VEGF functions after ischemia and reperfusion (I/R) injury. In this report, we first evaluated the expression of VEGF in a mouse model of liver warm ischemia. We found that the expression of VEGF increased after ischemia but peaked between 2 and 6 hours after reperfusion. Mice were treated with a neutralizing anti-mouse VEGF antiserum (anti-VEGF) or control serum daily from day -1 (1 day before the initiation of ischemia). Treatment with anti-VEGF significantly reduced serum glutaminic pyruvic transaminase levels and reduced histological evidence of hepatocellular damage compared with controls. Anti-VEGF also markedly decreased T-cell, macrophage, and neutrophil accumulation within livers and reduced the frequency of intrahepatic apoptotic terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling-positive cells. Moreover, there was a reduction in the expression of pro-inflammatory cytokines (tumor necrosis factor-alpha and interferon-gamma), chemokines (interferon-inducible protein-10 and monocyte chemoattractant protein-1) and adhesion molecules (E-selectin) in parallel with enhanced expression of anti-apoptotic genes (Bcl-2/Bcl-xl and heme oxygenase-1) in anti-VEGF-treated animals. In conclusion, hypoxia-inducible VEGF expression by hepatocytes modulates leukocyte trafficking and leukocyte-induced injury in a mouse liver model of warm I/R injury, demonstrating the importance of endogenous VEGF production in the pathophysiology of hepatic I/R injury.

Biliverdin Therapy Protects Rat Livers From Ischemia and Reperfusion Injury

Heme oxygenase (HO-1) provides a cellular defense mechanism during oxidative stress and catalyzes the rate-limiting step in heme metabolism that produces biliverdin (BV). The role of BV and its potential use in preventing ischemia/reperfusion injury (IRI) had never been studied. This study was designed to explore putative cytoprotective functions of BV during hepatic IRI in rat liver models of ex vivo perfusion and orthotopic liver transplantation (OLT) after prolonged periods of cold ischemia. In an ex vivo hepatic IRI model, adjunctive BV improved portal venous blood flow, increased bile production, and decreased hepatocellular damage. These findings were correlated with amelioration of histological features of IRI, as assessed by Suzuki's criteria. Following cold ischemia and syngeneic OLT, BV therapy extended animal survival from 50% in untreated controls to 90% to 100%. This effect correlated with improved liver function and preserved hepatic architecture. Additionally, BV adjuvant after OLT decreased endothelial expression of cellular adhesion molecules (P-selectin and intracellular adhesion molecule 1), and decreased the extent of infiltration by neutrophils and inflammatory macrophages. BV also inhibited expression of inducible nitric oxide synthase and proinflammatory cytokines (interleukin 1beta, tumor necrosis factor alpha, and interleukin 6) in OLTs. Finally, BV therapy promoted an increased expression of antiapoptotic molecules independently of HO-1 expression, consistent with BV being an important mediator through which HO-1 prevents cell death. In conclusion, this study documents and dissects potent cytoprotective effects of BV in well-established rat models of hepatic IRI. Our results provide the rationale for a novel therapeutic approach using BV to maximize the function and thus the availability of donor organs.

Cytoprotective and Antiapoptotic Effects of IL‐13 in Hepatic Cold Ischemia/Reperfusion Injury Are Heme Oxygenase‐1 Dependent

Liver injury caused by ischemia/reperfusion (I/R) insult represents the major problem following orthotopic liver transplantation (OLT). I/R damage has been linked to Th1‐like cytokine producers. This study evaluates putative cytoprotective effects/mechanisms of Th2‐type IL‐13 gene transfer. IL‐13 overexpression prevented hepatic insult in a rat model of 24 h cold ischemia followed by OLT, as assessed: (i) profoundly decreased hepatocellular damage (sGOT levels), and ameliorated histological signs of I/R injury (Suzuki criteria), consistent with long‐term OLT survival; (ii) prevented hepatic apoptosis (TUNEL stains) and up‐regulated expression of antiapoptotic (A20, Bcl‐2/Bcl‐xl)/antioxidant (HO‐1) genes. However, inhibition of HO‐1 with tin protoporphyrin reversed cytoprotective/antiapoptotic effects of IL‐13. In conclusion, cytoprotection rendered by virally induced IL‐13 against hepatic I/R injury in this clinically relevant rat hepatic cold I/R injury model was accomplished via decreased apoptosis and induction of antiapoptotic/antioxidant molecules. HO‐1 neutralization studies suggest that HO‐1 represents one of putative IL‐13 downstream effectors. This study provides the rationale for novel approaches to maximize organ donor pool through the safer use of OLTs despite prolonged periods of cold ischemia.

Biliverdin protects rat livers from Ischemia/Reperfusion injury

Objective To explore putative cytoprotective functions of biliverdin during hepatic ischemia/reperfusion (I/R) injury in rat models. Material and methods Male Sprague Dawley (SD) rat livers were harvested and stored for 24 hours at 4°C in University of Wisconsin (UW) solution ( n = 18), and then perfused with blood for 2 hours on an isolated rat liver perfusion apparatus equipped for temperature (37°C), pressure (13 cm H 2O), and pH (7.3) maintenance. Biliverdin was added to the blood at concentrations of 10 and 50 μmol in two groups of six animals. Portal vein blood flow, bile production, and GOT/GPT levels were assessed serially. At the conclusion of the experiment, liver samples were collected for histologic evaluation using Suzuki criteria. Results BV exerted protective effects against liver I/R injury. Adjunctive biliverdin improved portal venous blood flow (mL/min/g) from the beginning of reperfusion (1.33 ± 0.17 versus 0.98 ± 0.15; P < .001) and increased bile production (mL/g) as compared with the control group (3.40 versus 1.88; P < .003). I/R-induced hepatocellular damage as measured by GOT/GPT release (IU/L) was diminished in the biliverdin group (91 versus 171 and 46 versus 144, respectively; P < .0001). Improved liver function by biliverdin was accompanied by preservation of the histologic structure as assessed by Suzuki criteria (3.7 ± 1.4 versus 6.8 ± 0.8 in untreated controls; P < .005). Conclusions Biliverdin attenuates the ischemia/early reperfusion injury of rat liver grafts as assessed by hemodynamics, function, enzyme analysis, and histology. This study provides the rationale for novel therapeutic approaches using biliverdin to maximize the organ donor pool through the safer use of liver transplants despite prolonged periods of cold ischemia.

Interleukin-13 gene transfer protects rat livers from antigen-independent injury induced by ischemia and reperfusion.

Ischemia-reperfusion (I/R) injury is a prime inflammatory factor in the dysfunction of orthotopic liver transplants. Interleukin (IL)-13 suppresses macrophage production of proinflammatory mediators. This study explores the effects of adenovirus (Ad)-based IL-13 gene transfer in rat models of hepatic I/R injury. The authors used a model of warm in situ ischemia followed by reperfusion, and ex vivo cold ischemia followed by transplantation. In a model of warm in situ ischemia followed by reperfusion, Ad-based IL-13 significantly diminished hepatocellular injury, assessed by serum glutamic oxaloacetic transaminase (SGOT) levels, as compared with Ad-based beta-galactosidase (gal)-treated livers. In a model of ex vivo cold ischemia followed by transplantation, the survival of liver grafts increased from 50% in Ad-beta-gal untreated controls to 100% after Ad-IL-13 gene therapy. This beneficial effect correlated with improved liver function (SGOT levels), preservation of hepatic histologic integrity and architecture (Suzuki criteria), and depression of neutrophil infiltration (myeloperoxidase assay). Ad-IL-13 diminished activation of macrophage-neutrophil-associated tumor necrosis factor-alpha, macrophage inflammatory protein-2, and endothelial-dependent E-selectin, but increased type 2 IL-4 and IL-13 expression. This study documents striking cytoprotective effects of virally induced IL-13 against hepatic I/R injury in two clinically relevant rat models of hepatic I/R injury. These data provide the rationale for novel therapeutic approaches to maximize the organ donor pool through the safer use of liver transplants despite prolonged periods of warm or cold ischemia, or both.

Transcranial Doppler ultrasonography in patients with Moyamoya disease

This study included 17 patients (five men and 12 women) with clinical diagnosis of Moyamoya disease from conventional angiograms. Bilateral basal arteries were measured by the transtemporal approach with a 2 MHz pulsed Doppler instrument (TC-2 64B EME). In 28 out of the 34 basal arteries (82.4%), reliable recordings were obtained. These transcranial Doppler ultrasonography (TCD) findings were classified into three patterns: (1) High-high pattern; the mean cerebral blood flow velocity (CBFV) was increased throughout the basal arteries by over 70 cm/s (seven arteries, 25.0%); (2) high-low pattern; the mean CBFV was fastest (over 70 cm/s) at the ICA or proximal MCA and the mean CBFV decreased remarkably distally (15 arteries, 53.6%); and (3) low-low pattern; the mean CBFV was less than 40 cm/s throughout the basal arteries (arteries, 15.4%). These CBFV patterns as assessed by TCD are compared with the patients age, clinical symptoms and angiographical stagings (Suzuki's criteria). The high-high pattern on TCD was predominantly seen in the younger patients and in the earlier stages of the disease. The high-low pattern was the most common pattern of CBFV as assessed by TCD in Moyamoya patients. The low-low pattern on TCD was more common in the later stages following angiographic evaluation by Suzuki's criteria. The above patterns based on TCD findings show a good correlation with the age of the patient and the clinical diagnosis at the onset. TCD appears to be very useful in the evaluation of patients with Moyamoya disease.