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In northern Japan, juvenile chum salmon Oncorhynchus keta (Walbaum) are released from hatcheries to enhance the fishery resource. Infections with ectoparasitic protozoans, particularly the flagellate Ichthyobodo salmonis and the ciliate Trichodina truttae, occasionally cause severe mortality among hatchery‐reared juveniles. This study examined the susceptibility of the two parasites to wide‐ranging UV irradiation (experiment 1) and then investigated whether UV disinfection of the rearing water using a commercial device was useful for preventing infections among juveniles in a small‐scale rearing system over a 28‐day period (experiment 2). In experiment 1, parasite mortality reached 100% with UV irradiation doses of ≥9.60 × 105 μW s/cm2 for I. salmonis and ≥8.40 × 105 μW s/cm2 for T. truttae. In experiment 2, disinfection of the rearing water at a UV irradiation dose of 2.2 × 106 μW s/cm2 succeeded in complete prevention of both parasites in the juvenile salmon. These results elucidate the minimum dose of UV irradiation for inactivation of I. salmonis and T. truttae, and demonstrate the usefulness of water disinfection using a commercial UV irradiation device to prevent infections by these parasites in hatchery‐reared juvenile chum salmon. [ABSTRACT FROM AUTHOR]

The present study performed three experiments to establish a practical prevention strategy for the ectoparasitic flagellate Ichthyobodo salmonis and ciliate Trichodina truttae in hatchery‐reared juvenile chum salmon Oncorhynchus keta using dietary supplementation with oregano essential oil. Experiment 1 showed that a diet supplemented for 3 weeks with 0.02% oregano essential oil significantly prevented infection with I. salmonis and T. truttae in juveniles reared in small tanks. Experiment 2, in outdoor hatchery ponds, demonstrated that the oregano treatment completely prevented I. salmonis infection for 52 days and T. truttae infection for 38 days. Oregano‐treated juvenile mortality attributable to infection with these protozoans also decreased to 7.6% of control juvenile mortality, confirming the utility of this treatment in cultured O. keta. Physiological analyses of the oregano‐treated juveniles elucidated the treatment's safety in relation to their metabolism, osmoregulation, natural immunity and olfactory responses and also detected carvacrol (a major component of oregano essential oil which shows antimicrobial activity) on the skin. In experiment 3, exposure of the two protozoans to oregano essential oil revealed a weak antiparasitic action on the body surface of the juvenile O. keta. The overall results demonstrate that dietary oregano supplementation is a practical prevention strategy for I. salmonis and T. truttae in hatchery‐reared juvenile O. keta and suggest the possibility that its anti‐parasitic action is attributable to a component of the oil that emerges onto the skin of the body of the fish. [ABSTRACT FROM AUTHOR]

S-Alk(en)yl- l-cysteine sulfoxides are cysteine-derived secondary metabolites highly accumulated in the genus Allium. Despite pharmaceutical importance, the enzymes that contribute to the biosynthesis of S-alk-(en)yl- l-cysteine sulfoxides in Allium plants remain largely unknown. Here, we report the identification of a flavin-containing monooxygenase, As FMO1, in garlic ( Allium sativum), which is responsible for the S-oxygenation reaction in the biosynthesis of S-allyl- l-cysteine sulfoxide (alliin). Recombinant As FMO1 protein catalyzed the stereoselective S-oxygenation of S-allyl- l-cysteine to nearly exclusively yield ( RC SS)- S-allylcysteine sulfoxide, which has identical stereochemistry to the major natural form of alliin in garlic. The S-oxygenation reaction catalyzed by As FMO1 was dependent on the presence of nicotinamide adenine dinucleotide phosphate (NADPH) and flavin adenine dinucleotide (FAD), consistent with other known flavin-containing monooxygenases. As FMO1 preferred S-allyl- l-cysteine to γ-glutamyl- S-allyl- l-cysteine as the S-oxygenation substrate, suggesting that in garlic, the S-oxygenation of alliin biosynthetic intermediates primarily occurs after deglutamylation. The transient expression of green fluorescent protein ( GFP) fusion proteins indicated that As FMO1 is localized in the cytosol. As FMO1 mRNA was accumulated in storage leaves of pre-emergent nearly sprouting bulbs, and in various tissues of sprouted bulbs with green foliage leaves. Taken together, our results suggest that As FMO1 functions as an S-allyl- l-cysteine S-oxygenase, and contributes to the production of alliin both through the conversion of stored γ-glutamyl- S-allyl- l-cysteine to alliin in storage leaves during sprouting and through the de novo biosynthesis of alliin in green foliage leaves. [ABSTRACT FROM AUTHOR]

Hepatocyte growth factor (HGF) is essential for embryogenesis, tissue regeneration and tumour malignancy through the activation of its receptor, c-Met. We previously demonstrated that HGF α-chain hairpin-loop, K1 domain and β-chain are required for c-Met signalling. The sequential phosphorylation of tyrosine residues, from c-Met kinase domain to multidocking regions, is required for HGF-signalling transduction. Herein, we provide evidence that the disconcerted activation of c-Met tyrosine regions fails to induce biological functions. When human cells were incubated with 'mouse HGF', kinase domain activation (i.e. phospho-Tyr-1230/34/35) became evident, but the multidocking site ( i.e. Tyr-1349) was not phosphorylated, resulting in unsuccessful induction of migration and mitogenesis. The binding ability of mouse HGF α-chain, or of β-chain, to human c-Met was lower than that of human HGF, as evidenced by HGF-chimera assay. Notably, only four amino acid positions in HGF α-chain hairpin-loop and K1 domain and six positions in β-chain differed between human HGF and mouse HGF. The human-specific amino acids (such as Gln-95 in hairpin-loop, Arg-134 in K1 domain and Cys-561 in β-chain) may be important for accurate c-Met assembly and signalling transduction. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Podocytes provide a slit diaphragm to inhibit proteinuria, and nephrin between podocytes functions as a barrier during glomerular filtration. Hepatocyte growth factor (HGF) can improve proteinuria in rodents with various renal injuries, but little is known about the role of HGF in podocyte-based events during glomerulonephritis. In the present study, we examined whether and how nephrin expression is sustained by podocytes during the HGF-mediated attenuation of albuminuria. Lipopolysaccharide (LPS)-treated mice were used as an animal model of albuminuria. We evaluated the effect of HGF on slit proteins using immunohistochemistry, western blotting and real-time polymerase chain reaction. Albuminuria occurred 36 h after LPS treatment in mice. This albuminuria did not involve podocyte loss, but was associated with a decrease in nephrin and its key anchor, synaptopodin. In these processes, c-Met tyrosine phosphorylation, which represented HGF signal activation, occurred in glomerular cells including podocytes. When recombinant HGF was administrated to nephritic mice, c-Met tyrosine phosphorylation became evident in podocytes. The enhancement of the HGF-c-Met signal was associated with increases in nephrin and synaptopodin. An electron microscopic examination revealed that LPS induced the foot process effacement of podocytes, while HGF injections suppressed the foot process injury. Overall, albuminuria was attenuated in the LPS-treated mice after HGF administration. HGF protects podocytes from a loss of nephrin, at least in part, through maintaining synaptopodin. As a result, HGF was shown to sustain foot process structure, and albuminuria was attenuated under inflammation. This interesting study demonstrates that hepatocyte growth factor therapy can protect against lipopolysaccharide-induced albuminuria in mice by preventing effacement of the podocyte slit diaphragm, reducing glomerular macrophage infiltration and suppressing systemic inflammation. [ABSTRACT FROM AUTHOR]

1. Hepatocyte growth factor (HGF) has the therapeutic potential to improve renal fibrosis and proteinuria in rodents with chronic kidney disease. In contrast, long-term administration of human HGF to normal rats reportedly elicits proteinuria. Thus, the role of HGF during proteinuria remains contentious. The aim of the present study was to demonstrate that human HGF is antigenic to rodents and that immune complex formation causes proteinuria. 2. We administered either human or rat HGF to normal rats for 28 days. Albuminuria was evaluated by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. The renal phenotypes of the two HGF treatments were examined using histological techniques. 3. Administration of human HGF (1 mg/kg per day, i.v.) to rats led to severe albuminuria and glomerular hypertrophy in association with increased blood levels of anti-human HGF IgG and IgG deposition in mesangial areas. Furthermore, an immune complex between human HGF and anti-human HGF IgG stimulated the production of proteinuric cytokines (including transforming growth factor-β) in rat cultured mesangial cells. In contrast, treatment of healthy rats with rat HGF for 4 weeks caused neither mesangial IgG deposition nor elevated anti-HGF IgG in the blood. Overall, rat HGF did not provoke albuminuria. 4. We conclude that human HGF produces pseudotoxic effects in normal rat kidneys via an immune complex-mediated pathway, whereas syngenic HGF is safe due to less deposition of glomerular IgG. Our results affirm the safety of the repeated use of syngenic HGF for the treatment of chronic organ diseases, such as renal fibrosis and liver cirrhosis. [ABSTRACT FROM AUTHOR]

Hepatocyte growth factor (HGF) promotes malignant development of cancer cells by enhancing invasion and metastasis. NK4, a competitive antagonist for HGF, is a bifunctional molecule that acts as a HGF antagonist and angiogenesis inhibitor. Although successful tumor inhibition by NK4 gene expression in tumor models has been demonstrated, the effects of systemic NK4 gene introduction are yet to be addressed. Here we show that systemic administration of a replication-defective adenovirus expressing NK4 (Ad.NK4) inhibits tumor growth and lung metastasis of B16F10 melanoma and Lewis lung carcinoma in syngeneic mice. Single tail-vein injection of Ad.NK4 achieved therapeutic levels of NK4 in the circulation and in multiple organs. Despite NK4 expression that was highest in the liver, toxicity in the liver was minimal. Ad.NK4-mediated growth inhibition was associated with decreased blood vessel density and increased apoptosis in tumor tissues, which suggests that NK4 suppressed tumor growth as an angiogenesis inhibitor. Metastasis of B16F10 melanoma and Lewis lung carcinoma cells to the lung was potently inhibited by systemic Ad.NK4-administration. Our results demonstrated that the adenovirus-mediated induction of high levels of circulating NK4 significantly inhibited in vivo tumor growth and distant metastasis without obvious side effects. NK4 gene therapy is thus a safe and promising strategy for the treatment of cancer patients, and further validation in clinical trials is needed. ( Cancer Sci 2009; 100: 1351–1358) [ABSTRACT FROM AUTHOR]

In Japan, the phase distinction of masu salmon Oncorhynchus masou during smoltification is determined based on external appearance such as body silvering and black pigmentation of dorsal and caudal fin margin. This method is subjective, and it is difficult to quantify smoltification because body silvering and fin pigmentation level change continuously. Therefore, innovative and easily used criteria to establish smoltification are necessary. We therefore tested a chromameter (L-value) to measure body silvering in two brood years of hatchery-reared and natural (wild and hatchery-origin fish occurring in the wild) masu salmon and examined its effectiveness in determining the progress of smoltification as it relates to establishing smolt release time. Time required to measure body silvering using a chromameter was approximately 10 s per fish. For both brood years, the L-values of hatchery-reared and natural fish differed. With the progress of smoltification in both hatchery-reared and natural fish, the L-values increased gradually from 48.6 to 81.5. Significant linear correlations between L-value and dorsal fin pigmentation were observed in both hatchery-reared and natural groups, but these regression lines were not significantly different. These results suggest that the L-value can be used as a simple index to quantify body silvering during masu salmon smoltification and may be a useful tool in deciding their release time. [ABSTRACT FROM AUTHOR]

The distributions of phytohemagglutinin-P (PHA) and concanavalin A (ConA) binding sites were investigated for equine, bovine and canine peripheral blood lymphocytes (PBL). Non-B lymphocytes were collected from each PBL using a fluorescence-activated cell sorter (FACS), and the numbers of PHA and ConA binding sites on their surfaces were counted. Most PHA binding sites on PBL of the three species were shown on the surfaces of non-B lymphocytes. On the other hand, the ConA binding sites on equine and canine PBL existed mainly on the surfaces of non-B lymphocytes, but B lymphocytes of these two species had many ConA binding sites. These results were confirmed by the results of two-parameter fluorescence analysis using FACS. It is, therefore, concluded that the different optimum concentrations of PHA and ConA in PBL blastogenic responses of each animal depended on the different distributions of their binding sites. Zusammenfassung Die Ausprägung von Phytohämagglutinin-P und Concanavalin A-Bindungsstellen auf equinen, bovinen und caninen peripheren Blutlymphozyten Die Verteilung der Bindungsstellen für Phytohämagglutinin-P (PHA) and Concanavalin A (ConA) auf equinen, bovinen und caninen peripheren Blutlymphozyten (PBL) wurde untersucht. Die nicht der B-Zellreihe zugehörigen Lymphozyten aus den PBL jeder Spezies wurden mit Hilfe der Durchflußzytometrie (fluorescence activated cell sorter, FACS) separiert und die Zahl der PHA- und ConA-Bindungsstellen auf der Zelloberfläche bestimmt. Die meisten PHA-Bindungsstellen auf PBL der drei Spezies wurden auf der Oberfläche der nicht den B-Zellen zugehörigen Lymphozyten nachgewiesen. Im Gegensatz dazu waren zwar bei equinen und caninen PBL auch die meisten ConA-Bindungsstellen auf Nicht-B-Lymphozyten festzustellen, aber die B-Lymphozyten dieser zwei Spezies hatten ebenfalls zahlreiche ConA-Bindungsstellen. Diese Ergebnisse wurden durch die Zwei-Parameter-Fluoreszenzanalysen mit der Durchflußzytometrie bestätigt. Man kann daraus schließen, daß die verschiedenen optimalen Konzentrationen an PHA und ConA für die blastogene Lymphozytenantwort bei verschiedenen Tierarten von der unterschiedlichen Verteilung der Bindungsstellen für diese Lektine bestimmt werden. [ABSTRACT FROM AUTHOR]

Presents a study on the ability of hepatocyte growth factor (HGF) to reduce advancing lung fibrosis in mice which has a potential role for MMP-dependent myofibroblast apoptosis. Outcome of chronic respiratory failures and is histologically characterized by hyperplasia of interstitial myofibroblasts to deposit extracellular matrix; Method used to determine potential target cells of HGF in fibrotic murine lungs; Reason for examining the effects of HGF on myofibroblast survival, focusing on fibronectin and MMP-2/-9.

Deals with a study which developed a gene therapy strategy to prevent and ameliorate hearing impairment in rats. Administration of the hemagglutinating virus of Japan envelope vector; In vivo transfection of the hepatocyte growth factor (HGF) gene in the subarachnoid space; Therapeutic effect of hepatocyte growth factor on the inner ear.