Induction of hepatocyte growth factor/scatter factor by interferon-γ in human leukemia cells

Induction of hepatocyte growth factor/scatter factor (HGF/SF) may be one of the critical steps in organ regeneration, wound healing, and embryogenesis. We previously reported the production of HGF/SF from various human leukemia cell lines and a high level of the growth factor in blood and bone marrow plasma from patients with various types of leukemia. We determined here the effects of hematopoietic cytokines on HGF/SF production in human leukemia cell lines, KG-1, a myeloid cell line, and RPMI-8226, a B cell line. Interferon (IFN)-γ remarkably stimulated HGF/SF production in both cell lines at concentrations of more than 0.1 or 1 IU/ml. IFN-α and IFN-β were as effective as IFN-γ in RPMI-8226 cells, but less than IFN-γ in KG-1 cells. HGF/SF gene expression in KG-1 cells was also up-regulated by IFN-γ. Granulocyte colony-stimulating factor (G-CSF), granulocyte/macrophage colony-stimulating factor (GM-CSF), interleukin (IL)-5 and IL-6 had no effect on HGF/SF production in the 2 leukemia cell lines. We also determined the effects of HGF/SF inducers known for human fibroblasts on the growth factor production in leukemia cells. Out of phorbol 12-myristate 13-acetate (PMA), cholera toxin, IL-1β, and tumor necrosis factor (TNF)-α, the former three were as effective as IFN-γ in KG-1 cells, but only TNF-α stimulated HGF/SF production in RPMI-8226 cells, whose effect was less than those of IFN-α, IFN-β, and IFN-γ. The effect of IFN-γ in KG-1 cells was synergistic with that of PMA. In contrast with the effect in leukemia cells, HGF/SF induction by IFN-γ in human skin fibroblasts was much less than that by PMA or cholera toxin. These results indicated that IFN-γ is a potent inducer of HGF/SF in human leukemia cells. This finding suggests the presence of a homeostatic control mechanism in liver regeneration and repair: hepatic injury, DNA synthesis inhibition, or apoptosis caused by IFN-γ is subsequently overcome by cytokine-induced HGF/SF, a potent promoter of liver DNA synthesis. J. Cell. Physiol. 174:107–114, 1998. © 1998 Wiley-Liss, Inc.     

Changes in rabbit skeletal myosin and its subfragments under high hydrostatic pressure

The pressure-induced denaturation of rabbit skeletal myosin and its subfragments under hydrostatic pressure were investigated. Four nanometer of red shift of the intrinsic fluorescence spectrum was observed in myosin under a pressure of 400 MPa. The ANS fluorescence of myosin increased with elevating pressure. Changes in the intrinsic fluorescence spectra of myosin and its subfragments were quantified and expressed as the center of spectral mass. The center of spectral mass of myosin and its subfragments linearly decreased with elevating pressure, and increased with lowering pressure. The fluorescence intensity of the ANS-labeled rod did not change during pressure treatment. The present results indicate that the most pressure-sensitive portion of myosin molecule is the head. Hysteresis of the center of spectral mass of S1 appeared under pressures above 300 MPa. Changes in the center of spectral mass of S1 above 350 MPa showed stronger hysteresis. The center of spectral mass did not decrease above 350 MPa during the compression process, indicating that S1 was stable in a partially denatured state at 350 MPa under pressure. The changes in the relative intensities of ANS fluorescence of S1 were measured under pressures up to 400 MPa, and the ANS fluorescence intensity increased with elevating pressure but it did not change after pressure release. The ANS fluorescence intensity increased under constant pressure suggesting that the pressure-induced denaturation of myosin was accelerated during pressurization.     

New chemotypes for cathepsin K inhibitors

Cyano pyrimidine acetylene and cyano pyrimidine t-amine, which belong to a new chemical class, were prepared and tested for inhibitory activities against cathepsin K and the highly homologous cathepsins L and S. The use of novel chemotypes in the development of cathepsin K inhibitors has been demonstrated by derivatives of compounds 1 and 8.     

Attenuating effect of angiotensin-(1-7) on angiotensin II-mediated NAD(P)H oxidase activation in type 2 diabetic nephropathy of KK-A(y)/Ta mice

ANG-(1-7) is associated with vasodilation and nitric oxide synthase stimulation. However, the role of ANG-(1-7) in type 2 diabetes mellitus is unknown. In this study, we examined the hypothesis that ANG-(1-7) attenuates ANG II-induced reactive oxygen species stress (ROS)-mediated injury in type 2 diabetic nephropathy of KK-A(y)/Ta mice. KK-A(y)/Ta mice were divided into four groups: 1) a control group; 2) ANG II infusion group; 3) ANG II+ANG-(1-7) coinfusion group; and 4) ANG II+ANG-(1-7)+d-Ala(7)-ANG-(1-7) (A779) coinfusion group. In addition, primary mesangial cells were cultured and then stimulated with 25 mM glucose with or without ANG II, ANG-(1-7), and A779. The ANG II+ANG-(1-7) coinfusion group showed a lower urinary albumin/creatinine ratio increase than the ANG II group. ANG-(1-7) attenuated ANG II-mediated NAD(P)H oxidase activation and ROS production in diabetic glomeruli and mesangial cells. ANG II-induced NF-κB and MAPK signaling activation was also attenuated by ANG-(1-7) in the mesangial cells. These findings were related to improved mesangial expansion and to fibronectin and transforming growth factor-β1 production in response to ANG II and suggest that ANG-(1-7) may attenuate ANG II-stimulated ROS-mediated injury in type 2 diabetic nephropathy. The ACE2-ANG-(1-7)-Mas receptor axis should be investigated as a novel target for treatment of type 2 diabetic nephropathy.     

Multidrug-resistance-associated protein plays a protective role in menadione-induced oxidative stress in endothelial cells

AimsMenadione, a redox-cycling quinone known to cause oxidative stress, binds to reduced glutathione (GSH) to form glutathione S-conjugate. Glutathione S-conjugates efflux is often mediated by multidrug-resistance-associated protein (MRP). We investigated the effect of a transporter inhibitor, MK571 (3-[[3-[2-(7-chloroquinolin-2-yl)vinyl]phenyl]-(2-dimethylcarbamoylethylsulfanyl)methylsulfanyl] propionic acid), on menadione-induced oxidative stress in bovine aortic endothelial cells (BAECs).Main methodsBAECs were treated with menadione and MK571, and cell viability was measured. Modulation of intracellular GSH levels was performed with buthionine sulfoximine and GSH ethyl ester treatments. Intracellular superoxide was estimated by dihydroethidium oxidation using fluorescence microscopy or flow cytometry. Expression of MRP was determined by flow cytometry using phycoerythrin-conjugated anti-MRP monoclonal antibody.Key findingsIntracellular GSH depletion by buthionine sulfoximine promoted the loss of viability of BAECs exposed to menadione. Exogenous GSH, which does not permeate the cell membrane, or GSH ethyl ester protected BAECs against the loss of viability induced by menadione. The results suggest that GSH binds to menadione outside the cells as well as inside. Pretreatment of BAECs with MK571 dramatically increased intracellular levels of superoxide generated from menadione, indicating that menadione may accumulate in the intracellular milieu. Finally, we found that MK571 aggravated menadione-induced toxicity in BAECs and that MRP levels were increased in menadione-treated cells.SignificanceWe conclude that MRP plays a vital role in protecting BAECs against menadione-induced oxidative stress, presumably due to its ability to transport glutathione S-conjugate.     

A comprehensive radiation hybrid map of the bovine genome comprising 5593 loci

A bovine whole genome 7000-rad radiation hybrid (RH) panel, SUNbRH(7000-rad), was constructed to build a high-resolution RH map. The Shirakawa-USDA linkage map served as a scaffold to construct a framework map of 3216 microsatellites on which 2377 ESTs were ordered. The resulting RH map provided essentially complete coverage across the genome, with 1 cR7000 corresponding to 114 kb, and a cattle-human comparative map of 1716 bovine genes and sequences annotated in the human genome, which covered 79 and 72% of the bovine and human genomes, respectively. We then integrated the bovine RH and comparative maps with BAC fingerprint information in to construct a detailed, BAC-based physical map covering a reported 40-cM quantitative trait locus region for intramuscular fat or "marbling" on BTA 4. In summary, the new, high-resolution SUNbRH7000-rad, comparative, Shirakawa-USDA linkage, and BAC fingerprint maps provide a set of genomic tools for fine mapping regions of interest in cattle.     

Recurrent ovarian cancer presenting as an isolated right supraclavicular lymph node metastasis: a case report

ABSTRACT: INTRODUCTION: The majority of ovarian cancer recurrences are in the abdomen. However, some cases relapseas isolated lymph node metastases, mostly in pelvic or para-aortic nodes. Peripheral isolatedlymph node metastasis is rare. CASE PRESENTATION: A 69-year-old Japanese woman had recurrent ovarian cancer presenting with isolated rightsupraclavicular lymph node metastasis. After surgical resection and combinationchemotherapy with carboplatin and paclitaxel, her right supraclavicular lymph nodecompletely regressed. CONCLUSIONS: Isolated peripheral lymph node metastasis, including the right supraclavicular lymph node,can occur without a macroscopic abdominal lesion. Clinicians should carefully examineperipheral lymph nodes for recurrence.