Sustained induction of hepatocyte growth factor by sensitization with freeze-thawed hepatic tissue

Hepatocyte growth factor (HGF) is a mitogen for hepatocytes, and has therapeutic potential for fibrotic/cirrhotic liver. Therefore, the induction of HGF in vivo is considered to be useful in the treatment of liver dysfunction caused by cirrhosis, chronic hepatitis, or extensive surgical resection. In this study, we examined the sustained induction of HGF by inoculation of freeze-thawed hepatic tissue (FTHT). Serum from rats inoculated with FTHT increased [³H]thymidine incorporation i.e., increased DNA synthesis, in primary cultured rat hepatocytes. The DNA synthesis was significantly promoted by the addition of the FTHT-sensitized serum, while this DNA synthesis was inhibited by neutralizing anti-rat HGF antibody. The concentration of HGF in the FTHT-sensitized serum was increased by day 3 after the inoculation. The time of HGF induction was dependent on the inoculated volume of FTHT, but peaks of HGF concentration were found on day 5 with different volumes of FTHT. Injurins, inducers of HGF, were also induced in the FTHT-sensitized rats, with their peak levels on day 3. The FTHT inoculated tissue showed inflammatory cell infiltration, which was gradually absorbed, and had completely disappeared by day 14 after the inoculation. Although mild inflammatory cell infiltration was observed in non-freeze-thawed inoculated hepatic tissue (NFHT) a tight capsule formed around the NFHT, and was scarcely phagocytized on day 14. These results suggest that FTHT inoculation induces HGF sustainedly through the increased synthesis of injurins, and that freeze-thawed tissue, which is easily phagocytized, is important for the sustained induction of HGF. Received for publication on Sept. 6, 1997; accepted on April 8, 1998     

Metabolism of N,N-dipropyl-2-[4-methoxy-3-(2-phenyl-ethoxy)-phenyl]-ethyl-amine-monohydrochloride (NE-100), a novel sigma ligand: contribution of cytochrome P450 forms involved in the formation of individual metabolites in human liver and small intestine

In the present study, human cytochrome P450 (CYP) forms involved in producing the primary metabolites of NE-100 were identified. Major metabolites of NE-100 in human liver microsomes (HLM) were N-depropylation of NE-100 (NE-098), p-hydroxylation of phenyl group of NE-100 (NE-152), m-hydroxylation of phenyl group of NE-100 (NE-163) and O-demethylation of NE-100 (NE-125). Judging from the correlation and inhibition studies, NE-125 and NE-152+163mix formations were predominantly mediated by CYP2D6 and NE-098 formation was mediated by multiple CYP forms at a low NE-100 concentration (0.1 microM) in the HLM. According to relative activity factor (RAF) approaches, all these reactions were predominantly catalyzed by CYP2D6 at a substrate concentration assuming a plasma level of NE-100 (K(m)>S) in case of the human liver. Depending on the increase in NE-100 concentrations, the rate of contribution for NE-098 and NE-152+163mix formations increased in CYP3A4, although the predominant contribution of CYP2D6 for NE-125 formation did not change. In human intestinal microsomes (HIM), NE-100 was mainly metabolized to NE-098 and NE-152+163mix by CYP3A4. The intrinsic clearance for their formations in HIM was 3.2 and 14.9 times less than those in HLM, respectively, and no formation of NE-125 was observed in HIM. These results strongly suggest that CYP2D6 is the predominant form for NE-100 metabolism in the human liver in in vivo conditions (K(m)>S) and the liver plays a more important role than does the small intestine in the first pass metabolism.     

Myelofibrosis after essential thrombocythemia complicated by alveolar proteinosis

Hematological diseases are often accompanied by respiratory disorders. Pulmonary alveolar proteinosis (PAP) is a rare disease characterized by excessive accumulation of surfactant in the alveolar space. We describe a case of PAP complicated by myelofibrosis following essential thrombocythemia. The patient developed high fever, respiratory failure, and leuko-erythroblastosis during the progressive course of PAP. These symptoms were alleviated by prednisolone. The level of serum IL-6 was elevated when PAP was progressing rapidly. This may explain why the symptoms were alleviated by the steroids.     

Relationship between peroxisome proliferator-activated receptors (PPAR alpha and PPAR gamma) and endothelium-dependent relaxation in streptozotocin-induced diabetic rats

(1) The aim of the present study was to investigate the causal relationship between peroxisome proliferator-activated receptor (PPAR) and endothelium-dependent relaxation in streptozotocin (STZ)-induced diabetic rats. (2) Acetylcholine (ACh)-induced endothelium-dependent relaxation was significantly weaker in diabetic rats than in age-matched controls. The decreased relaxation in diabetes was improved by the chronic administration of bezafibrate (30 mg kg-1, p.o., 4 weeks). (3) The expressions of the mRNAs for PPARalpha and PPARgamma were significantly decreased in STZ-induced diabetic rats (compared with the controls) and this decrease was restored partially, but not completely, by the chronic administration of bezafibrate. (4) Superoxide dismutase activity in the aorta was not significantly different between diabetic rats and bezafibrate-treated diabetic rats. (5) The expression of the mRNA for the p22phox subunit of NAD(P)H oxidase was significantly higher in diabetics than in controls, but it was lower in bezafibrate-treated diabetic rats than in nontreated diabetic rats. Although the expression of the mRNA for prepro ET-1 (ppET-1) was markedly increased in diabetic rats (compared with controls), this increase was prevented to a significant extent by the chronic administration of bezafibrate. (6) These results suggest that downregulations of PPARalpha and PPARgamma may lead to an increased expression of ppET-1 mRNA in diabetic states and this increment may trigger endothelial dysfunction.     

Effective extracorporeal shock wave lithotripsy for pancreatic duct stone

A 55-year-old man with alcoholic chronic pancreatitis was hospitalized for further treatment of intractable repeated upper abdominal pain. A laboratory data showed normal hepatobiliary enzymes and glucose tolerance test, but abnormal pancreatic enzymes including amylase, lipase, trypsin and elastase I. Pancreatic function diagnostant test was 71%. Abdominal ultrasound examination and computed tomography showed an approximately 4 mm main pancreatic duct stone and multiple small stones in the surrounding parenchyma, and the findings being compatible with chronic pancreatitis. Endoscopic retrograde cholangiopancreatrography revealed that there was a main pancreatic duct stone in the pancreas head, and that the caudal pancreatic duct could not be visualized due to the impacted stone. In addition, intrapancreatic bile duct showed no malignant irregularity, but pancreatitis-induced smooth narrowing. The patient underwent extracorporeal shock wave lithotripsy (ESWL) alone, because endoscopic manipulation for pancreatic stone removal was impossible due to tightly impacted stone with stenosis. Successful ESWL was achieved with the stone disappearance and without any complication.     

Evaluation of resection of the papilla of Vater for the treatment of cancer in the papilla of Vater

We evaluated the resection of the papilla of Vater performed in patients with cancer in the papilla of Vater. The subjects were 6 patients who underwent resection of the papilla of Vater between January 1969 and December 2001. The patients aged 57-87 years consisted of 3 males and 3 females. The maximal diameter of the tumors was 0.5 cm in 1 patient, 1.5 cm in 3 patients, and 2.0 cm in 2 patients. Macroscopically, the tumors were of the protruded type (exposed) in 3 patients, of the mixed type (predominant protruded type) in 2 patients, and of the ulcerative type in 1 patient. The histological depth of the tumors was up to the mucosa in 1 patient, up to the oddi in 1 patient, up to the panc0, du1 in 1 patient, up to the panc1, du2 in 1 patient, and unknown in 2 patients. Histologically, the tumors were papillotubular adenocarcinoma (pap-tub) in 4 patients and tubular adenocarcinoma of the well-differentiated type (tub1) in 2 patients. Resection of the papilla of Vater was chosen because of high risk factors such as advanced age in 2 patients, complicated severe cirrhosis and confinement to bed due to poor systemic conditions after intracerebral hemorrhage in 3 patients, and hepatic metastasis observed during surgery in 1 patient. Residual cancer cells around the excised region were positive in 4 patients and unknown in the remaining 2 patients. Of the 6 patients, 5 died within 2 years after surgery, but 1 is alive without symptoms of recurrence 7 years after surgery. The death causes were the primary disease in 3 of the 5 patients. From the viewpoint of radical treatment, resection of the papilla of Vater cannot be chosen as a reduced surgery for cancer in the papilla of Vater. However, resection of the papilla of Vater can be applied to very elderly patients and patients under poor systemic conditions, for whom pancreatoduodenectomy (PD) is considered excessively invasive due to a small diameter of tumor.     

A case of subependymal giant cell astrocytoma not associated with tuberous sclerosis

The authors present a case of a subependymal giant cell astrocytoma (SGCA) not associated with tuberous sclerosis. On admission, a six-year-old boy had obstructive hydrocephalus caused by a huge intraventricular tumor. Preoperative T1-weighted MR images with gadolinium showed heterogeneous enhancement of the lesion. The tumor was totally removed through a right transcortical approach with frontal craniotomy. Immunohistochemical staining for glial fibrillary acidic protein (GFAP) showed a positive reaction in some of the large tumor cells and the labeling index of MIB-1 was < 1.0%. Histological examinations revealed SGCA. He has no other evidence of tuberous sclerosis at present, but the patient in this case is an infant, so there is a possibility of his being diagnosed as tuberous sclerosis in the future. Therefore, systemic regular follow-up is recommended, even when his condition is asymptomatic.     

Effect of antibodies against intercellular adhesion molecule-1, B7, and CD40 on interleukin-18-treated human mixed lymphocyte reaction

The interleukin (IL)-18 level in plasma is elevated during the acute rejection after organ transplantation. IL-18 elicits adhesion molecule expression as well as interferon-gamma/IL-12 production and T-cell proliferation in the human mixed lymphocyte reaction, an in vitro model of acute rejection. We examined whether antibodies (Abs) against intercellular adhesion molecule (ICAM)-1, B7, CD40, and CD40, ligand (CD40L) affect the cytokine production and T-cell proliferation. Anti-ICAM-1 and B7 Abs suppressed the cytokine production, while all Abs inhibited T-cell proliferation. ICAM-1 and B7 as well as CD40 may play different roles in the acute rejection.     

Phosphorylation of c-Cbl protooncogene product following ethanol administration in rat cerebellum: possible involvement of Fyn kinase

We have previously shown that ethanol administration results in tyrosine phosphorylation of the 130 kDa protein in rat brain, and identified the protein as Cas, the crk-associated src substrate. In the present study, we demonstrate that Cbl of a 120 kDa protein is also tyrosine-phosphorylated in the cerebellum in response to ethanol administration. We also investigated whether Fyn kinase was involved in ethanol-induced Cbl phosphorylation. Immunoprecipitation experiments showed that the amount of coimmunoprecipitated Fyn kinase with an anti-Cbl antibody increased in extracts from ethanol-administered rats compared to those from saline-administered rats. Exogenous Fyn kinase was shown to phosphorylate on tyrosine residue(s) of Cbl from the cerebellum in vitro. Furthermore, Fyn kinase and Cbl were demonstrated immunohistochemically to be coexpressed in white matter in the cerebellum. These findings indicate that Cbl is tyrosine-phosphorylated in rat cerebellum in response to ethanol administration, and also raise the possibility that Fyn kinase may be involved in the process.