Metallothionein gene family in the sea urchin Paracentrotus lividus: Gene structure, differential expression and phylogenetic analysis

Metallothioneins (MT) are small and cysteine-rich proteins that bind metal ions such as zinc, copper, cadmium, and nickel. In order to shed some light on MT gene structure and evolution, we cloned seven Paracentrotus lividus MT genes, comparing them to Echinodermata and Chordata genes. Moreover, we performed a phylogenetic analysis of 32 MTs from different classes of echinoderms and 13 MTs from the most ancient chordates, highlighting the relationships between them. Since MTs have multiple roles in the cells, we performed RT-qPCR and in situ hybridization experiments to understand better MT functions in sea urchin embryos. Results showed that the expression of MTs is regulated throughout development in a cell type-specific manner and in response to various metals. The MT7 transcript is expressed in all tissues, especially in the stomach and in the intestine of the larva, but it is less metal-responsive. In contrast, MT8 is ectodermic and rises only at relatively high metal doses. MT5 and MT6 expression is highly stimulated by metals in the mesenchyme cells. Our results suggest that the P. lividus MT family originated after the speciation events by gene duplications, evolving developmental and environmental sub-functionalization

An intronic cis-regulatory element is crucial for the alpha tubulin Pl-Tuba1a gene activation in the ciliary band and animal pole neurogenic domains during sea urchin development

In sea urchin development, structures derived from neurogenic territory control the swimming and feeding responses of the pluteus as well as the process of metamorphosis. We have previously isolated an alpha tubulin family member of Paracentrotus lividus (Pl-Tuba1a, formerly known as Pl-Talpha2) that is specifically expressed in the ciliary band and animal pole neurogenic domains of the sea urchin embryo. In order to identify cis-regulatory elements controlling its spatio-temporal expression, we conducted gene transfer experiments, transgene deletions and site specific mutagenesis. Thus, a genomic region of about 2.6 Kb of Pl-Tuba1a, containing four Interspecifically Conserved Regions (ICRs), was identified as responsible for proper gene expression. An enhancer role was ascribed to ICR1 and ICR2, while ICR3 exerted a pivotal role in basal expression, restricting Tuba1a expression to the proper territories of the embryo. Additionally, the mutation of the forkhead box consensus sequence binding site in ICR3 prevented Pl-Tuba1a expression

Multiple IgE recognition on the major allergen of the Parietaria pollen Par j 2

tThe interaction between IgE antibodies and allergens is a key event in triggering an allergic reaction. Thecharacterization of this region provides information of paramount importance for diagnosis and therapy.Par j 2 Lipid Transfer Protein is one of the most important allergens in southern Europe and a well-established marker of sensitization in Parietaria pollen allergy. The main aim of this study was to map theIgE binding regions of this allergen and to study the pattern of reactivity of individual Parietaria-allergicpatients. By means of gene fragmentation, six overlapping peptides were expressed in Escherichia coli, andtheir IgE binding activity was evaluated by immunoblotting in a cohort of 79 Parietaria-allergic patients.Our results showed that Pj-allergic patients display a heterogeneous pattern of IgE binding to the differentrecombinant fragments, and that patients reacted simultaneously against several protein domains spreadall the over the molecule, even in fragments which do not contain structural features resembling thenative allergen. Our results reveal the presence of a large number of linear and conformational epitopeson the Par j 2 sequence, which probably explains the high allergenic activity of this allergen

A cross-sectional study assessing the relationship between BMI, asthma, atopy, and eNO among schoolchildren

Increased body weight may influence airway inflammatory mechanisms

Determinants of Allergic Sensitization, Asthma and Lung Function: Results from a Cross-Sectional Study in Italian Schoolchildren

Prenatal smoking exposure and early-life respiratory infections are major determinants of asthma during childhood. We investigate the factors influencing allergic sensitization (AS), asthma, and lung function in children and the balance between individual and environmental characteristics at different life stages. 1714 children aged 7-16 years and living in southern Italy were investigated using a parental questionnaire, skin prick tests, and spirometry. We found 41.0% AS prevalence: among children without parental history of asthma, male sex, maternal smoking during pregnancy (MatSmoke), and acute respiratory diseases in the first two years of life (ARD2Y) were significant risk factors for AS. MatSmoke was associated (OR = 1.79) with ARD2Y, and this association was influenced by sex. ARD2Y was, in turn, a significant risk factor (OR = 8.53) for childhood current asthma, along with AS (OR up to 3.03) and rhinoconjuctivitis (OR = 3.59). Forced mid-expiratory flow (FEF25-75%) was negatively affected by ARD2Y, with a sex-related effect. Thus, males exposed to MatSmoke had significantly lower FEF25-75% than unexposed males. Despite the difficulty of discriminating among the complex interactions underlying the development of allergic respiratory diseases, ARD2Y appears to strongly influence both asthma and lung function during childhood. In turn, ARD2Y is influenced by prenatal exposure to tobacco smoke with a sex-dependent effect

Proadrenomedullin NH(2)-terminal 20 peptide (PAMP) and adrenomedullin bind to teratocarcinoma cells.

Proadrenomedullin NH(2-)terminal 20 peptide (PAMP) and adrenomedullin (ADM) bind to teratocarcinoma cells. The effects of PAMP and ADM on teratocarcinoma cells were investigated. (125)I-PAMP bound to PA1 cells with moderate affinity (K(d) = 110 nM) to a single class of sites (B(max) = 110 000/cell). Specific (125)I-PAMP binding was inhibited by PAMP (IC(50) of 100 nM) but not ADM, calcitonin gene-related peptide (CGRP), or amylin. Specific (125)I-ADM binding was inhibited with high affinity by ADM, CGRP, and CGRP(8-37) (IC(50) values of 10, 10, and 15 nM respectively) but not PAMP or amylin. ADM elevated cAMP (ED(50) value of 100 nM), whereas PAMP had no effect on basal cAMP but inhibited the increase in cAMP caused by 10 nM ADM. Also, the increase in cAMP caused by ADM was inhibited CGRP(8-37), suggesting that ADM is binding to CGRP receptors. ADM (100 nM) stimulated transiently c-fos mRNA, whereas PAMP (1000 nM) had little effect; however, PAMP inhibited the increase in c-fos mRNA caused by ADM. ADM stimulated [(3)H]thymidine uptake into PA1 cells, whereas PAMP inhibited the increase in thymidine uptake caused by ADM. These results indicate that ADM and PAMP are both biologically active in teratocarcinoma cells

Non-specific bronchial hyper-responsiveness in children with allergic rhinitis: relationship with the atopic status

An increased prevalence of bronchial hyper-responsiveness (BHR) has been demonstrated in children from a general population, and in non-asthmatic adults with allergic rhinitis. Thus, also children with allergic rhinitis are expected to be at higher risk of BHR. We evaluated the prevalence of BHR in a sample of non-asthmatic children with allergic rhinitis by means of the methacholine (Mch) bronchial challenge, and by monitorizing the airway patency using the daily peak expiratory flow variability (PEFv). Fifty-one children (ranged 6-15 years of age) with allergic rhinitis, ascertained by skin prick test to inhalant allergens, underwent a 14-day peak expiratory flow monitoring, and a Mch bronchial provocation challenge. Thirty healthy children matched for age, and sex served as control group. Thirty-one children in the rhinitis group (61%), and six (20%) in the control group were Mch+ (Mch provocative dose causing a 20% fall of forced expiratory volume in 1 s respect to baseline <2250 microg, equivalent to 11.50 micromol). In rhinitic children the PEFv did not significantly differ between Mch+ and Mch- subjects, but the total serum immunoglobulin E (IgE) were higher among Mch+. The persistent form of rhinitis was significantly associated to Mch positivity. Non-asthmatic children with allergic rhinitis displayed a high prevalence of BHR. The BHR was significantly associated with persistent rhinitis and with higher total IgE levels. Nevertheless, the spontaneous changes in airway patency, as expressed by PEFv, were within normal limits both in Mch+ and Mch- children

Adrenomedullin in mammalian embryogenesis

Here are summarized data supporting that adrenomedullin (AM) is a multifunctional factor involved in the complex regulatory mechanisms of mammalian development. During rodent embryogenesis, AM is first expressed in the heart, followed by a broader but also defined spatio-temporal pattern of expression in vascular, neural, and skeletal-forming tissues as well as in the main embryonic internal organs. AM pattern of expression is suggestive of its involvement in the control of embryonic invasion, proliferation, and differentiation processes, probably through autocrine or paracrine modes of action. AM levels in fetoplacental tissues, uterus, maternal and umbilical plasma are highly increased during normal gestation. These findings in addition to other physiological and gene targeting studies support the importance of AM as a vasorelaxant factor implicated in the regulation of maternal vascular adaptation to pregnancy, as well as of fetal and fetoplacental circulations. AM is also present in amniotic fluid and milk, which is suggestive of additional functions in the maturation and immunological protection of the fetus. Altered expression of AM has been found in some gestational pathologies, although it is not yet clear whether this corresponds to causative or compensatory mechanisms. Future studies in regard to the distribution and expression levels of the molecules known to function as AM receptors, together with data on the action of complement factor H (an AM binding protein), may help to better define the roles of AM during embryonic development

Bronchial hyperresponsiveness in children with atopic rhinitis: a 7-year follow-up

A high prevalence of bronchial hyperresponsiveness (BHR) was found in atopic subjects with rhinitis. Those subjects may be at higher risk for developing bronchial asthma. We evaluated, in a 7-year follow-up, BHR and atopy in a homogeneous population of nonasthmatic children with allergic rhinitis (AR), and their role in asthma development

Taurine regulates insulin release from pancreatic beta cell lines

<p>Abstract</p> <p>Background</p> <p>Pancreatic β-cells release insulin via an electrogenic response triggered by an increase in plasma glucose concentrations. The critical plasma glucose concentration has been determined to be ~3 mM, at which time both insulin and GABA are released from pancreatic β-cells. Taurine, a β-sulfonic acid, may be transported into cells to balance osmotic pressure. The taurine transporter (TauT) has been described in pancreatic tissue, but the function of taurine in insulin release has not been established. Uptake of taurine by pancreatic β-cells may alter membrane potential and have an effect on ion currents. If taurine uptake does alter β-cell current, it might have an effect on exocytosis of cytoplasmic vesicle. We wished to test the effect of taurine on regulating release of insulin from the pancreatic β-cell.</p> <p>Methods</p> <p>Pancreatic β-cell lines Hit-TI5 (Syrian hamster) and Rin-m (rat insulinoma) were used in these studies. Cells were grown to an 80% confluence on uncoated cover glass in RPMI media containing 10% fetal horse serum. The cells were then adapted to a serum-free, glucose free environment for 24 hours. At that time, the cells were treated with either 1 mM glucose, 1 mM taurine, 1 mM glucose + 1 mM taurine, 3 mM glucose, or 3 mM glucose + 1 mM taurine. The cells were examined by confocal microscopy for cytoplasmic levels of insulin.</p> <p>Results</p> <p>In both cell lines, 1 mM glucose had no effect on insulin levels and served as a control. Cells starved of glucose had a significant reduction (p<0.001) in the level of insulin, but this level was significantly higher than all other treatments. As expected, the 3 mM glucose treatment resulted in a statistically lower (p<0.001) insulin level than control cells. Interestingly, 1 mM taurine also resulted in a statistically lower level of insulin (p<0.001) compared to controls when either no glucose or 1 mM glucose was present. Cells treated with 1 mM taurine plus 3 mM glucose showed a level of insulin similar to that of 3 mM glucose alone.</p> <p>Conclusions</p> <p>Taurine administration can alter the electrogenic response in β-cell lines, leading to a change in calcium homeostasis and a subsequent decrease in intracellular insulin levels. The consequence of these actions could represent a method of increasing plasma insulin levels leading to a decrease in plasma glucose levels.</p