Phenotypic and genetic characterization of the Atp7a(Mo-Tohm) mottled mouse: a new murine model of Menkes disease

Mottled Tohoku (Atp7a(Mo-Tohm) or Mo(Tohm)) is an X-linked mutation with mottled pigmentation in heterozygous (Mo(Tohm)/+) females and is embryonic lethal at E11 in hemizygous (Mo(Tohm)/Y) males. Copper levels were low in the brain and high in the intestine of Mo(Tohm) mice. Two congenic strains with ICR or C57BL/6 (B6) background were produced for genetic and phenotypic analyses and revealed that Mo(Tohm)/+ females with ICR background survived until adulthood, while most with B6 background died within 2 days after birth. The Mo(Tohm)/Y males with both backgrounds died at around E11. Massive hemorrhage was shown in the yolk sac cavity with irregular attachment between the mesoderm and the endothelial cells of blood vessels in the embryos at E10.5, suggesting that this irregular attachment causes embryonic lethality. The Mo(Tohm) mutant had a 1440-bp deletion between intron 22 and exon 23 of the Atp7a gene. Mo(Tohm)/Y males with the wild-type Atp7a cDNA transgene were rescued from embryonic lethality, confirming that the Mo(Tohm) mutant is caused by the defect in the Atp7a gene. This mutant mouse is the most severe model of human Menkes disease in mottled mice established to date and one of the useful models for understanding the gene function of Menkes disease.     

Genome-wide expression analysis of yeast response during exposure to 4°C

Adaptation to temperature fluctuation is essential for the survival of all living organisms. Although extensive research has been done on heat and cold shock responses, there have been no reports on global responses to cold shock below 10°C or near-freezing. We examined the genome-wide expression in Saccharomyces cerevisiae, following exposure to 4°C. Hierarchical cluster analysis showed that the gene expression profile following 4°C exposure from 6 to 48 h was different from that at continuous 4°C culture. Under 4°C exposure, the genes involved in trehalose and glycogen synthesis were induced, suggesting that biosynthesis and accumulation of those reserve carbohydrates might be necessary for cold tolerance and energy preservation. The observed increased expression of phospholipids, mannoproteins, and cold shock proteins (e.g., TIP1) is consistent with membrane maintenance and increased permeability of the cell wall at 4°C. The induction of heat shock proteins and glutathione at 4°C may be required for revitalization of enzyme activity, and for detoxification of active oxygen species, respectively. The genes with these functions may provide the ability of cold tolerance and adaptation to yeast cells.     

Vasohibin prevents arterial neointimal formation through angiogenesis inhibition

Vasohibin is a VEGF-inducible angiogenesis inhibitor in vascular endothelium. Here we examined the presence of vasohibin in human arterial wall, and found it in endothelium of adventitial microvessels in atherosclerotic lesion. Adventitial angiogenesis is involved in the progression of neointimal formation. Even in the presence of endogenous angiogenesis inhibitors, pathological angiogenesis persists. However, the supplementation of exogenous angiogenesis inhibitors can prevent pathological angiogenesis. We evaluated the potential role of vasohibin in neointimal formation. Adenovirus-mediated human vasohibin gene transfer in mouse liver resulted in the release of vasohibin in plasma and exhibited anti-angiogenic effects at remote sites. This gene transfer inhibited adventitial angiogenesis, macrophage infiltration, and neointimal formation after cuff placement on mouse femoral artery. Vasohibin exhibited no direct effect on migration and proliferation of smooth muscle cells. Thus, vasohibin has an activity to prevent neointimal formation by inhibiting adventitial angiogenesis.     

Acceleration of matrix metalloproteinase-1 production and activation of platelet-derived growth factor receptor beta in human coronary smooth muscle cells by oxidized LDL and 4-hydroxynonenal

Increases in matrix metalloproteinases (MMPs) at atherosclerotic lesions are involved in the migration of smooth muscle cells (SMCs) into the intima and to the rupture of plaques, being implicated in the progression of atherosclerosis. The present study examined the mechanisms underlying the production of MMP-1, interstitial collagenase-1, induced by oxidized low-density lipoprotein (oxLDL) and 4-hydroxynonenal (4-HNE), factors proposed to play a pivotal role in atherogenesis, in human coronary SMCs. oxLDL promoted the production of MMP-1 with the preceding phosphorylation of extracellular signal-regulated kinase (ERK) 1/2. Immunoprecipitation of platelet-derived growth factor receptor beta (PDGFR-beta) revealed that oxLDL induced tyrosine phosphorylation of the receptor. Inhibition of the activation of PDGFR-beta and ERK1/2 resulted in a suppression of the production of MMP-1. Consistently, 4-HNE also elicited the production of MMP-1 with the preceding phosphorylation of PDGFR-beta and ERK1/2. The 4-HNE-induced production of MMP-1 was prevented when the activation of PDGFR-beta and ERK1/2 was inhibited. The present results suggest that the activation of PDGFR-beta and ERK1/2 is involved in the production of MMP-1 in oxLDL- and 4-HNE-stimulated human coronary SMCs.     

Molecular cloning of estrogen receptor alpha of the Nile crocodile

Estrogens are essential for normal reproductive activity in female and male vertebrates. In female reptiles, they are essential for ovarian differentiation during a critical developmental stage. To understand the molecular mechanisms of estrogen action in the Nile crocodile (Crocodylus niloticus), we have isolated cDNA encoding the estrogen receptor alpha (ERalpha) from the ovary. Degenerate PCR primers specific to ER were designed and used to amplify Nile crocodile cDNA from the ovary. The full-length Nile crocodile ERalpha cDNA was obtained using 5' and 3' rapid amplification cDNA ends (RACE). The deduced amino acid sequence of the Nile crocodile ERalpha showed high identity to the American alligator ERalpha (98%), caiman ER (98%), lizard ER (82%) and chicken ERalpha (92%), although phylogenetic analysis suggested profound differences in the rate of sequence evolution for vertebrate ER sequences. Expression of ERalpha was observed in the ovary and testis of juvenile Nile crocodiles. These data provide a novel tool allowing future studies examining the regulation and ontogenic expression of ERalpha in crocodiles and expands our knowledge of estrogen receptor evolution.     

Expression and function of inducible co-stimulator in patients with systemic lupus erythematosus: possible involvement in excessive interferon-γ and anti-double-stranded DNA antibody production

Inducible co-stimulator (ICOS) is the third member of the CD28/cytotoxic T-lymphocyte associated antigen-4 family and is involved in the proliferation and activation of T cells. A detailed functional analysis of ICOS on peripheral blood T cells from patients with systemic lupus erythematosus (SLE) has not yet been reported. In the present study we developed a fully human anti-human ICOS mAb (JTA009) with high avidity and investigated the immunopathological roles of ICOS in SLE. JTA009 exhibited higher avidity for ICOS than a previously reported mAb, namely SA12. Using JTA009, ICOS was detected in a substantial proportion of unstimulated peripheral blood T cells from both normal control individuals and patients with SLE. In CD4⁺CD45RO⁺ T cells from peripheral blood, the percentage of ICOS⁺ cells and mean fluorescence intensity with JTA009 were significantly higher in active SLE than in inactive SLE or in normal control individuals. JTA009 co-stimulated peripheral blood T cells in the presence of suboptimal concentrations of anti-CD3 mAb. Median values of [³H]thymidine incorporation were higher in SLE T cells with ICOS co-stimulation than in normal T cells, and the difference between inactive SLE patients and normal control individuals achieved statistical significance. ICOS co-stimulation significantly increased the production of IFN-γ, IL-4 and IL-10 in both SLE and normal T cells. IFN-γ in the culture supernatants of both active and inactive SLE T cells with ICOS co-stimulation was significantly higher than in normal control T cells. Finally, SLE T cells with ICOS co-stimulation selectively and significantly enhanced the production of IgG anti-double-stranded DNA antibodies by autologous B cells. These findings suggest that ICOS is involved in abnormal T cell activation in SLE, and that blockade of the interaction between ICOS and its receptor may have therapeutic value in the treatment of this intractable disease.     

Production of donor-derived offspring by allogeneic transplantation of Spermatogonia in the yellowtail (Seriola quinqueradiata)

Although the yellowtail (Seriola quinqueradiata) is the fish most commonly farmed in Japan, breeding of this species has not yet started. This is primarily due to the lack of sufficiently sophisticated methods for manipulating gametogenesis, which makes it difficult to collect gametes from specific dams and sires. If it were possible to produce large numbers of surrogate fish by transplanting germ cells isolated from donor individuals harboring desirable genetic traits, then the probability of acquiring gametes carrying the donor-derived haplotype would increase, and breeding programs involving this species might increase as a result. As a first step, we established a method for the allogeneic transplantation of yellowtail spermatogonia and the production of donor-derived offspring. Donor cells were collected from immature (10-month-old) yellowtail males with testes containing abundant type A spermatogonia, labeled with PKH26 fluorescent dye, and transferred into the peritoneal cavities of 8-day-old larvae. Fluorescence observation at 28 days post-transplantation revealed that PKH26-labeled cells were incorporated into recipients' gonads. To assess whether donor-derived spermatogonia could differentiate into functional gametes in the allogeneic recipient gonads, gametes collected from nine male and four female adult recipients were fertilized with wild-type eggs and milt. Analysis of microsatellite DNA markers confirmed that some of the first filial (F(1)) offspring were derived from donor fish, with the average contribution of donor-derived F(1) offspring being 66% and the maximum reaching 99%. These findings confirmed that our method was effective for transplanting yellowtail spermatogonia into allogeneic larvae to produce donor-derived offspring.     

Lipopolysaccharide-induced Overproduction of Nitric Oxide and Overexpression of iNOS and Interleukin-1β Proteins in Zinc-deficient Rats

Zinc deficiency leads to decreased cellular immune responses. The overproduction of nitrogen species derived from inducible nitric oxide synthase (iNOS), its enzyme, and interleukine-1 beta (IL-1β), and inflammatory cytokine have been implicated in immune responses. The goal of this study was to investigate the effects of lipopolysaccharide (LPS)-induced changes in NO metabolites, iNOS, and IL-1β protein expression in the lungs of zinc-deficient rats. Male Sprague–Dawley rats (body weight, 100 g) were divided into two groups and were fed either a zinc-deficient diet (ZnD) or a zinc-containing diet (Cont). After 4 weeks on these diets, rats received a 10-mg/kg dose of LPS injected via the tail vein and were then maintained for an additional 72 h. To determine total NO concentrations in the blood, serum zinc concentration, iNOS protein expression, IL-1β, and iNOS immunohistochemistry, blood and lung samples were obtained at pre-LPS injection, 5, 24, and 72 h after injection. Total NO levels were significantly increased at 5, at 24, and at 72 h after LPS injection compared with pre-LPS injection level in ZnD group; significant changes in total NO levels was elevated at 5 h from at pre-LPS level but not significant changes from basal level at 24 and 72 h in the control group. Based on western blot analyses and immunohistochemistry, clear bands indicating iNOS and IL-1β protein expression and iNOS antibody-stained inflammatory cells were detected at 5 and 24 h in the ZnD group and 5 h in the Cont group, not observed at 24 and 72 h in the control group. These results suggest that zinc deficiency induces overexpression of iNOS and IL-1β proteins from inflammatory cells around the alveolar blood vessels, resulting in overproduction of total NO and persisted inflammatory response in the zinc-deficient rat lung. Taken together, overexpression of LPS-induced iNOS, overproduction of iNOS-derived NO, and overexpression of IL-1β may induce nitrosative and oxidative stresses in the lung, and these stresses may be involved low immunity of zinc deficiency states.     

Synthesis and interaction with midkine of biotinylated chondroitin sulfate tetrasaccharides

Regiospecifically sulfated chondroitin sulfate repeating tetrasaccharides, CS-OO, GlcAβ-GalNAcβ-GlcAβ-GalNAcβ;CS-EE, GlcAβ-GalNAc(4S6S)β-GlcAβ-GalNAc(4S6S)β; and CS-AA, GlcAβ-GalNAc(4S)β-GlcAβ-GalNAc(4S)β, having biotin linked with a hydrophilic linker at the reducing terminal were synthesized effectively by a coupling of the corresponding disaccharide units and regioselective sulfation. CS-EE showed greater affinity for midkine than CS-AA and CS-OO.