Plasma adrenomedullin concentration is increased in patients with peripheral arterial occlusive disease associated with vascular inflammation

Adrenomedullin (AM), a potent vasodepressor, is known to have anti-atherosclerotic and anti-inflammatory effects. However, there is no information about its level in severe atherosclerotic diseases, such as peripheral arterial occlusive disease (PAOD). The present study investigated the plasma concentration of AM and several inflammatory parameters in 72 patients with and without PAOD. The plasma AM concentration in patients with PAOD was significantly higher than in those without PAOD. Its concentration had significant correlations with ankle-brachial index and Fontaine's stage. The plasma AM level also correlated with high sensitive C-reactive protein and interleukin-6. As an additional study, plasma levels of two forms of AM drawn from the femoral artery and saphenous vein were measured in 27 other subjects. Both mature and intermediate forms of plasma AM in the femoral artery and saphenous vein were higher in patients with PAOD than in those without PAOD. A significant step-up of the mature form of AM from the femoral artery to the saphenous vein was observed. Our findings indicate that the plasma AM concentration was elevated in patients with PAOD in proportion to the severity of the disease and associated with vascular inflammation. An increased production of AM in PAOD may play a protective role against advanced atherosclerosis with an inflammatory signature.     

Flower color modulations of Torenia hybrida by downregulation of chalcone synthase genes with RNA interference

Suppression of biosynthetic genes involved in flower color formation is an important approach for obtaining target flower colors. Here we report that flower color of the garden plant Torenia hybrida was successfully modulated by RNA interference (RNAi) against a gene of chalcone synthase (CHS), a key enzyme for anthocyanin and flavonoid biosynthesis. By using each of the coding region and the 3'-untranslated region of the CHS mRNA as an RNAi target, exhaustive and gene-specific gene silencing were successfully induced, and the original blue flower color was modulated to white and pale colors, respectively. Our results indicate that RNAi is quite useful for modulations of flower colors of commercially important garden plants.     

Development of an efficient enzymatic production of gamma-D-glutamyl-L-tryptophan (SCV-07), a prospective medicine for tuberculosis, with bacterial gamma-glutamyltranspeptidase

Gamma-D-Glutamyl-L-tryptophan (SCV-07) is a prospective medicine for the treatment of tuberculosis, according to the phase two clinical trial. Because gamma-D-glutamyl-L-tryptophan has several reactive groups in its molecule, consists of D- and L-amino acids, and is connected by gamma-glutamyl linkage, its chemical synthesis is complicated. An efficient enzymatic method to synthesize gamma-D-glutamyl-L-tryptophan from D-glutamine and L-tryptophan employing bacterial gamma-glutamyltranspeptidase was developed. The optimum reaction conditions were 50 mM D-glutamine, 50 mM L-tryptophan, and 0.2 U ml(-1) gamma-glutamyltranspeptidase, pH 9-9.5, and incubation at 37 degrees C for 5 h. After a 5 h incubation, 33 mM gamma-D-glutamyl-L-tryptophan was obtained, the conversion rate being 66%. The product was purified by Dowex 1 x 8 column and was considered to be gamma-D-glutamyl-L-tryptophan.     

Induction of uPA release in human peripheral blood lymphocytes by [deamino-Cysl,D-Arg8]-vasopressin (dDAVP)

[deamino-Cys(l),d-Arg(8)]-vasopressin (dDAVP), known to be an arginine vasopressin (AVP) V(2) receptor agonist, is an agent that increases fibrinolytic activity levels in plasma after its infusion into the human body. However, mechanisms underlying an increase and exact localization of the extrarenal dDAVP-responsive V(2) receptor remain unclarified. Two AVP receptors, V(1a) and V(2), and a related oxytocin (OT) receptor were found to be expressed in human lymphocytes. Furthermore, we found an increase of fibrinolytic activity in the medium of peripheral lymphocytes obtained from human volunteers less than 20 min after dDAVP infusion. The increased activity was also detected in the medium after incubating the lymphocytes in the presence of dDAVP in vitro, being highest at 20 min after the incubation. In accord with the increased fibrinolytic activity, the levels of urokinase-type plasminogen activator (uPA) in the medium were also increased. However, there was no significant difference of plasminogen activator inhibitor-1 (PAI-1), pro-uPA, and tissue-type plasminogen activator (tPA) concentrations in the medium between dDAVP treatment and control. When lymphocytes were preincubated with a V(2) receptor antagonist [Adamantaneacetyl(1),O-Et-d-Tyr(2),Val(4),Aminobutyryl(6),Arg(8,9)]-vasopressin, the dDAVP-induced uPA increase was diminished. In contrast, preincubation with a V(1) receptor antagonist, [beta-Mercapto-beta,beta-cyclopentamethylenepropionyl(1),O-Me-Tyr(2),Arg(8)]-vasopressin, prior to dDAVP treatment resulted in a greater increase of the uPA concentration in the medium than with the dDAVP treatment alone. Thus it was suggested that dDAVP may induce uPA release from human lymphocytes via V(2) receptor-mediated reaction, and also via cross-talk between V(1) and V(2) receptors.     

Expression of a sweet cherry DREB1/CBF ortholog in Arabidopsis confers salt and freezing tolerance

Dehydration responsive element binding protein 1 (DREB1)/C-repeat binding factor (CBF) induces the expression of many stress-inducible genes in Arabidopsis. We have previously reported the identification of three DREB1/ICBF homologs from sweet cherry (Prunus avium). To identify the function of these homologs, one of the genes, CIG-B, was transformed into Arabidopsis. In one of the transgenic plant lines, the DREB1/CBF target gene cor15a was induced in the absence of stress treatment. The cor15a-overexpressing transgenic plant exhibited mild growth retardation and had greater salt and freezing tolerance than did the wild-type and the transgenic lines in which cor15a was not induced. These results suggest that this sweet cherry DREB1/CBF homolog has a function similar to that of DREB1/CBF.     

Adrenomedullin as a sensitive marker for coronary and peripheral arterial complications in patients with atherosclerotic risks

Plasma adrenomedullin (AM) levels are elevated in various pathological states including cardiovascular and inflammatory diseases. The present study investigated whether an increased AM level is a marker of vascular complications in patients with atherosclerotic risks. In 114 patients with cardiovascular risks and/or diseases including ischemic heart disease (IHD) and peripheral arterial disease (PAD), plasma AM concentration and other inflammatory markers such as high sensitive C-reactive protein (CRP) and interleukin (IL)-6 were examined. The plasma AM level was not altered by the absence or presence of each of four major risk factors, i.e., hypertension, diabetes mellitus, hyperlipidemia, and smoking and its level was not significantly correlated with blood pressure, plasma glucose, or serum lipid levels. The patients with IHD had a significantly higher concentration of plasma AM than those without IHD. The AM level in subjects with PAD was also increased significantly compared with those without PAD. The plasma AM was strongly correlated with inflammatory parameters such as CRP and IL-6. Among AM, CRP, and IL-6, however, only AM was an independent predictor for both IHD and PAD by multiple logistic regression analysis. Our findings suggest the possibility that plasma AM is a novel sensitive marker for the presence of vascular lesions in patients with atherosclerotic risks.     

Genetic variations at urotensin II and urotensin II receptor genes and risk of type 2 diabetes mellitus in Japanese

Urotensin II is among the most potent vasoactive hormones known and the urotensin II (UTS2) gene is localized to 1p36-p32, one of the regions reported to show possible linkage with type 2 diabetes in Japanese. When we surveyed genetic polymorphisms in the UTS2 and urotensin II receptor (GPR14) gene, we identified two SNPs with amino acid substitutions (designated T21M and S89N and an SNP in the promotor region (-605G>A) of the UTS2 gene, and two SNPs in the non-coding region of the GPR14 gene. We then studied these three SNPs in the UTS2 gene and two SNPs in the GPR14 gene in 152 Japanese subjects with type 2 diabetes mellitus and two control Japanese populations. The allele frequency of 89N was significantly higher in type 2 diabetic patients than in both elderly normal subjects (P = 0.0018) and subjects with normal glucose tolerance (P = 0.0011), whereas the allele frequency of T21M and -605G>A in the UTS2 gene and those of two SNPs in the GPR14 gene were essentially identical in these three groups. Furthermore, in the subjects with normal glucose tolerance, 89N was associated with significantly higher insulin levels on oral glucose tolerance test, suggesting reduced insulin sensitivity in subjects with 89N. These results strongly suggest that subjects with S89N in the UTS2 gene are more insulin-resistant and thus more susceptible to type 2 diabetes mellitus development.     

Microbiological activities contributing to nitrogen removal with methane: effects of methyl fluoride and tungstate

When methane (CH(4)) and O(2) are present, nitrogen can be removed from wastewater that does not contain other organic carbon sources. In this study, microbial activities during methane-dependent denitrification (MDD) were investigated by adding inhibitors of methane-oxidation and denitrification. Sludge susceptible to MDD showed methane oxidation activity in the presence of CH(4) and O(2), and denitrification activity with methanol and acetate under anoxic conditions. Methyl fluoride (CH(3)F) is known to inhibit methane oxidation. When CH(3)F was present, MDD did not occur, perhaps because methane oxidation was inhibited. Tungstate (WO(4)(2-)), a known inhibitor of nitrate reduction, also lowered denitrification activity in the sludge, and partly inhibited methane oxidation. When WO(4)(2-) was added to the medium, MDD almost ceased, perhaps because of a synergic inhibitory effect on denitrification and methane oxidation. These results show that both methane oxidation and denitrification contribute to MDD.