Blood histamine is associated with coronary artery disease,cardiac events and severity of inflammation and atherosclerosis

Background : Mast cells are prevalent in the shoulder of unstable atheromas; cardiac mast cells secrete proteases capable of activating matrix metalloproteinases. Histamine is essential in the inflammatory cascade of the unstable plaque. Ascorbate depletion has been correlated with histaminemia which has been shown to impair endothelial-dependent vasodilation. This study evaluates whether oxidative stress as measured by isoprostanes (PGF_2α) coupled with an inflammatory state characterized by histaminemia predisposes patients to acute coronary syndrome (ACS).
Methods : Whole blood histamine, serum vitamin C, and serum PGF_2α levels were drawn on 50 patients with ACS as determined by standard diagnostic criteria, 50 patients with stable coronary artery disease (SCAD), and 50 age and sex matched normal controls (C).
Results : Data were analyzed by stepwise discriminant and Spearman's rank correlation coefficient. A significant relationship exists between histamine and PGF_2α. As PGF_2α rises above 60 pg/mL, an increase in histamine occurs in both the ACS and SCAD groups. A significant inverse relationship exists between ascorbate and histamine in the ACS versus C groups (P < 0.01) and the SCAD versus C groups (P < 0.01).
Conclusion : Histamine and isoprostane levels increase in SCAD and ACS patients. Mast cell activation and lipid oxidation generated during atherosclerosis manifest this inflammatory response. Accelerated isoprostane formation and depleted ascorbate paired with histaminemia is active in CAD and predispose patients to acute coronary syndrome. Blood histamine alone may be a better risk factor for coronary events, and a better prognostic indicator than CRP even when combined with lipid indexes.     

Dynamic rearrangement of the filamentous actin network occurs during zoosporogenesis and encystment in the oomycete phytophthora cinnamomi

The organization of filamentous actin (F-actin) in living cells of the oomycete Phytophthora cinnamomi was determined during zoosporogenesis and zoospore encystment by microinjecting sporangia with fluorescently labeled phalloidin and observing resultant fluorescence by confocal microscopy. In multinucleate sporangia prior to the induction of cleavage, phalloidin labeling took the form of plaques which occurred mainly in the periphery of the sporangia. After induction of cleavage, phalloidin labeling showed that the plaques disappeared and that F-actin began to accumulate along the developing cleavage planes and around nuclei and water expulsion vacuoles. F-actin labeling was also observed near the plasma membrane in zoospores and young cysts but reverted to the plaque form in older cysts. Localization of F-actin close to the developing cleavage planes is consistent with the idea that actin microfilaments function in the positioning and expansion of the cleavage membranes. Observations of plaques of actin in living sporangia provide evidence that plaques are not aldehyde-induced fixation artifacts. Copyright 1998 Academic Press.     

Serglycin expression during monocytic differentiation of U937-1 cells

Serglycin is the major proteoglycan in most hematopoietic cells, including monocytes and macrophages. The monoblastic cell line U937-1 was used to study the expression of serglycin during proliferation and differentiation. In unstimulated proliferating U937-1 cells serglycin mRNA is nonconstitutively expressed. The level of serglycin mRNA was found to correlate with the synthesis of chondroitin sulfate proteoglycan (CSPG). The U937-1 cells were induced to differentiate into different types of macrophage-like cells by exposing the cells to PMA, RA, or VitD3. These inducers of differentiation affected the expression of serglycin mRNA in three different ways. The initial upregulation seen in the normally proliferating cells was not observed in PMA treated cells. In contrast, RA increased the initial upregulation, giving a reproducible six times increase in serglycin mRNA level from 4 to 24 h of incubation, compared to a four times increase in the control cells. VitD3 had no effect on the expression of serglycin mRNA. The incorporation of (35S)sulfate into CSPG decreased approximately 50% in all three differentiated cell types. Further, the (35S)CSPGs expressed were of larger size in PMA treated cells than controls, but smaller after RA treatment. This was due to the expression of CSPGs, with CS-chains of 25 and 5 kDa in PMA and RA treated cells, respectively, compared to 11 kDa in the controls. VitD3 had no significant effect on the size of CSPG produced. PMA treated cells secreted 75% of the (35S)PGs expressed, but the major portion was retained in cells treated with VitD3 or RA. The differences seen in serglycin mRNA levels, the macromolecular properties of serglycin and in the PG secretion patterns, suggest that serglycin may have different functions in different types of macrophages.      

Characterization of the ATPase and unwinding activities of the yeast DEAD-box protein Has1p and the analysis of the roles of the conserved motifs

The yeast DEAD-box protein Has1p is required for the maturation of 18S rRNA, the biogenesis of 40S r-subunits and for the processing of 27S pre-rRNAs during 60S r-subunit biogenesis. We purified recombinant Has1p and characterized its biochemical activities. We show that Has1p is an RNA-dependent ATPase in vitro and that it is able to unwind RNA/DNA duplexes in an ATP-dependent manner. We also report a mutational analysis of the conserved residues in motif I (⁸⁶AKTGSGKT⁹³), motif III (²²⁸SAT²³⁰) and motif VI (³⁷⁵HRVGRTARG³⁸³). The in vivo lethal K92A substitution in motif I abolishes ATPase activity in vitro. The mutations S228A and T230A partially dissociate ATPase and helicase activities, and they have cold-sensitive and lethal growth phenotypes, respectively. The H375E substitution in motif VI significantly decreased helicase but not ATPase activity and was lethal in vivo. These results suggest that both ATPase and unwinding activities are required in vivo. Has1p possesses a Walker A-like motif downstream of motif VI (³⁸³GTKGKGKS³⁹⁰). K389A substitution in this motif significantly increases the Has1p activity in vitro, which indicates it potentially plays a role as a negative regulator. Finally, rRNAs and poly(A) RNA serve as the best stimulators of the ATPase activity of Has1p among the tested RNAs.     

Human stanniocalcin-2 exhibits potent growth-suppressive properties in transgenic mice independently of growth hormone and IGFs

Stanniocalcin (STC)-2 was discovered by its primary amino acid sequence identity to the hormone STC-1. The function of STC-2 has not been examined; thus we generated two lines of transgenic mice overexpressing human (h)STC-2 to gain insight into its potential functions through identification of overt phenotypes. Analysis of mouse Stc2 gene expression indicates that, unlike Stc1, it is not highly expressed during development but exhibits overlapping expression with Stc1 in adult mice, with heart and skeletal muscle exhibiting highest steady-state levels of Stc2 mRNA. Constitutive overexpression of hSTC-2 resulted in pre- and postnatal growth restriction as early as embryonic day 12.5, progressing such that mature hSTC-2-transgenic mice are approximately 45% smaller than wild-type littermates. hSTC-2 overexpression is sometimes lethal; we observed 26-34% neonatal morbidity without obvious dysmorphology. hSTC-2-induced growth retardation is associated with developmental delay, most notably cranial suture formation. Organ allometry studies show that hSTC-2-induced dwarfism is associated with testicular organomegaly and a significant reduction in skeletal muscle mass likely contributing to the dwarf phenotype. hSTC-2-transgenic mice are also hyperphagic, but this does not result in obesity. Serum Ca2+ and PO4 were unchanged in hSTC-2-transgenic mice, although STC-1 can regulate intra- and extracellular Ca2+ in mammals. Interestingly, severe growth retardation induced by hSTC-2 is not associated with a decrease in GH or IGF expression. Consequently, similar to STC-1, STC-2 can act as a potent growth inhibitor and reduce intramembranous and endochondral bone development and skeletal muscle growth, implying that these tissues are specific physiological targets of stanniocalcins.     

Localisation of the Vacuolar Proton Pump (V-H+-ATPase) and Carbonic Anhydrase II in the Human Eccrine Sweat Gland

The localisation of the vacuolar proton pump (V-H+ -ATPase) and the enzyme carbonic anhydrase II (CAII) was investigated in the human eccrine sweat gland employing standard immunohistochemical techniques after antigen retrieval using microwave heat treatment and high pressure. The high-pressure antigen retrieval unmasked the presence of V-H+ -ATPase in the clear cells of the secretory coil, with a distribution similar to that previously observed for CAII. However, the dark cells were unreactive to both antibodies. In addition, heat and high-pressure antigen retrieval demonstrated the presence of CAII in the apical zone of luminal cells of the reabsorptive duct, a location not previously reported. The localisation of V-H+ -ATPase and CAII in the secretory coil clear cells suggests that the formation of HCO3- and H+ by carbonic anhydrase II and the transport of H+ by V-H+ -ATPase may play an role in sweat fluid secretion. Their presence at the apex of the duct cells indicates involvement in ductal ion reabsorption.     

First Extensive Polyphenolic Profile of Erodium cicutarium with Novel Insights to Elemental Composition and Antioxidant Activity

Erodium cicutarium is known for its total polyphenolic content, but this work reveals the first highly detailed profile of E. cicutarium, obtained with UHPLC‐LTQ OrbiTrap MS⁴ and UHPLC‐QqQ‐MS/MS techniques. A total of 85 phenolic compounds were identified and 17 constituents were quantified. Overall, 25 new compounds were found, which have not yet been reported for the Erodium genera, or the family Geraniaceae. Along with methanolic extracts, the so far poorly investigated water extracts exhibited in vitro antioxidant activity according to all performed assays, including the ferric reducing/antioxidant power assay (FRAP), 2,2‐diphenyl‐1‐picrylhydrazyl assay (DPPH), 2,2′‐azinobis(3‐ethylbenzthiazoline‐6‐sulfonic acid) assay (ABTS) and cupric ion reducing antioxidant capacity assay (CUPRAC). Elemental composition analysis performed with inductively coupled plasma atomic emission spectrometry (ICP‐AES) and, additionally, hydride generation atomic absorption spectrometry (HydrEA‐ETAAS) showed six most abundant elements to be decreasing as follows: Mg>Ca>K>S>P>Na, and gave first data regarding inorganic arsenic content (109.3–248.4 ng g^?1). These results suggest E. cicutarium to be a valuable source of various phenolic compounds with substantial potential for further bioactivity testing.