Chromogranin A and its role in the pathogenesis of diabetes mellitus

Chromogranin A is a member of the granin glycoprotein family that is expressed by the endocrine and neuroendocrine cells of different organs. Intracellularly, Chromogranin A contributes to the regulation of secretion, and gives several cleavage products after secretion. Some of its cleavage products modify the hormone functions in autocrine and paracrine ways, while the functions of others have not been fully understood yet. Serum Chromogranin A level is most prominently used in neuroendocrine tumor diagnostics. In addition, recent studies have suggested that Chromogranin A and some of its cleavage products, pancreastatin and WE-14, also play important roles in the pathogenesis of the various forms of diabetes mellitus, but their exact mechanisms still need to be clarified. Higher Chromogranin A, pancreastatin and WE-14 levels have been reported in type 1, type 2 and gestational diabetic patients compared to healthy controls. A notable connection has been inferred through the observation that type 1 diabetes mellitus is not at all or rarely developed in Chromogranin A gene-knockout, non-obese diabetic model mice compared to non-knockout, non-obese diabetic mice. Pancreastatin inhibits insulin release in various cell and animal models, and WE-14 serves as an autoantigen for both CD4+ and CD8+ beta cell-destructive diabetogenic T-cell clones in type 1 diabetes. Chromogranin A contributes to the pathogenesis of diabetes mellitus according to the available literature. The current findings facilitate further investigation to unravel the deeper relationships between this glycoprotein and diabetes

Nehézion ütközésekben nagy transzverzális impulzussal keletkezett töltött hadronok azonosítása és vizsgálata a CERN LHC ALICE kísérletben = Identification and investigation of charged hadrons produced with large transverse momenta in heavy ion collisions at the CERN LHC ALICE experiment

Kutatócsoportunk részt vesz a CERN LHC ALICE együttműködésben. Az alábbi tudományos eredményeket értük el 2006-2009 között: -A, HMPID detektor: Részt vettünk a HMPID megépítésében és installálásában, on-line monitorozó software-t fejlesztettünk ki. Adatgyüjtésben vettünk részt a kozmikus és az első pp ütközési periódusban. 2009-től Molnár Levente a kísérlet Run Coordinatora. -B, VHMPID fejlesztés: Trigger modul kifejlesztése nagy impulzusú hadronokra, új technológiai megoldások vizsgálata (Gáz Elektron Sokszorozó - GEM). Az ALIROOT-ba beillesztettük a VHMPID-et. Kisméretű prototípus elkészítése és tesztelése a CERN PS-nél. -C, Tier-2 ALICE GRID állomás az RMKI-ban: A dedikált GRID nagysága: 100 CPU, 30 TB tároló 2009-ben. . -D, Elméleti eredményeink (nagy-pT fizika, HMPID, VHMPID specifikusan): PP és PbPb ütközésben tanulmányoztuk nagy impulzusú részecskék keletkezési mechanizmusait: parton fragmentáció és pQCD, közel-termikus rendszerek Tsallis-eloszlással, nem-perturbatív párkeltés időfügggő intenzív terekben. Kvark koleszcencia modellünket továbbfejlesztettük és alkalmaztunk. 2-jet és 3-jet eseményeket vizsgáltuk. Nehézion ütközésben kezdeti és végállapoti kölcsönhatást vizsgáltunk, igy a jetek energiaveszteségét. Eredményeinket 40 tudományos közleményben jelentettük meg: 24 cikk referált újságban (IF: 68), 9 cikk conferencia kötetben, 2 e-print formájában, valamint 2 poszter és 3 szerkesztett proceedings. A csoport WEB-oldala: http://alice.kfki.hu/ | Our research group participates in the CERN LHC ALICE collaboration. During 2006-2009 we have accomplished the following results: -A, HMPID detector: Participation in the construction and installation; developing on-line monitoring software. We run cosmic ray data collection and start pp. Molnár L. became Run Coordinator in 2009. -B, VHMPID upgrade: Development of a high-pT trigger module, study new technologies, e.g. Gas Electron Multipliers (GEM). ALIROOT is improved for VHMPID simulations. Small size prototype has been tested in pion testbeam. -C, Tier-2 ALICE GRID station at RMKI: The ALICE dedicated GRID unit consists of 100 CPU and 30 TB storage in 2009. -D, Theoretical studies related to VHMPID and high-pT physics High momentum particle production and correlation in pp and PbPb collisions were studied: parton fragmentation described by perturbative QCD, near-thermal models containing Tsallis distributions and non-perturbative pair production in time dependent intense fields. Quark coalescence model has been improved and applied. 2-jet and 3-jet events have been studied. In PbPb collisions initial state and final state effects, especially jet energy loss has been investigated. We published 40 papers: 24 papers in refereed journals (IF: 68), 9 papers in conference proceedings, 2 e-prints, 2 posters, 3 edited proceedings of High-pT Workshops. Our WEB-page: http://alice.kfki.hu

第950回千葉医学会整形外科例会

Immunodetection of transfected proteins by various antibodies. a SDS-PAGE immunoblot of transiently expressed WUS:GFP variants co-expressed with various MPKs. b SDS-PAGE immunoblot of transiently expressed WUS:myc co-expressed with various MPKs. Negative control (neg. cont.) is a protoplast sample not transfected with the myc epitope. The right panel shows detection of transiently expressed WUS:myc by a specific anti-WUS antibody. Negative control (neg. cont.) is a protoplast sample not transfected with the WUS:myc construct. c SDS-PAGE immunoblot of transiently expressed WUS:myc variants. The proteasome inhibitor MG-115 was used to determine the role of protein degradation in the formation of the lighter bands detected. d SDS-PAGE immunoblot of various transiently expressed MPKs used in this study. iMPK3 designates an inactive MPK3 mutant. Negative control (neg. cont.) is a protoplast sample not transfected with the HA epitope. e Consistency of WUS:myc detection by cIEF-immunoassay. Transiently expressed WUS:myc was detected by the following antibodies: specific anti-WUS (Agrisera, top panel), HRP-coupled anti-myc (Roche) and anti-myc (Sigma). The antibodies used in this study are presented in detail in Additional File 8 Table S3. (PDF 260 kb

MASP-1 Increases Endothelial Permeability

Pathologically increased vascular permeability is an important dysfunction in the pathomechanism of life-threatening conditions, such as sepsis, ischemia/reperfusion, or hereditary angioedema (HAE), diseases accompanied by uncontrolled activation of the complement system. HAE for example is caused by the deficiency of C1-inhibitor (the main regulator of early complement activation), which leads to edematous attacks threatening with circulatory collapse. We have previously reported that endothelial cells become activated during HAE attacks. A natural target of C1-inhibitor is mannan-binding lectin-associated serine protease-1 (MASP-1), a multifunctional serine protease, which plays a key role in the activation of complement lectin pathway. We have previously shown that MASP-1 induces the pro-inflammatory activation of endothelial cells and in this study we investigated whether MASP-1 can directly affect endothelial permeability. All experiments were performed on human umbilical vein endothelial cells (HUVECs). Real-time micro electric sensing revealed that MASP-1 decreases the impedance of HUVEC monolayers and in a recently developed permeability test (XperT), MASP-1 dose-dependently increased endothelial paracellular transport. We show that protease activated receptor-1 mediated intracellular Ca2+-mobilization, Rho-kinase activation dependent myosin light chain (MLC) phosphorylation, cytoskeletal actin rearrangement, and disruption of interendothelial junctions are underlying this phenomenon. Furthermore, in a whole-transcriptome microarray analysis MASP-1 significantly changed the expression of 25 permeability-related genes in HUVECs—for example it up-regulated bradykinin B2 receptor expression. According to our results, MASP-1 has potent permeability increasing effects. During infections or injuries MASP-1 may help eliminate the microbes and/or tissue debris by enhancing the extravasation of soluble and cellular components of the immune system, however, it may also play a role in the pathomechanism of diseases, where edema formation and complement lectin pathway activation are simultaneously present. Our findings also raise the possibility that MASP-1 may be a promising target of anti-edema drug development

MASP-1 Induces a Unique Cytokine Pattern in Endothelial Cells: A Novel Link between Complement System and Neutrophil Granulocytes

Microbial infection urges prompt intervention by the immune system. The complement cascade and neutrophil granulocytes are the predominant contributors to this immediate anti-microbial action. We have previously shown that mannan-binding lectin-associated serine protease-1 (MASP-1), the most abundant enzyme of the complement lectin pathway, can induce p38-MAPK activation, NFkappaB signaling, and Ca(2+)-mobilization in endothelial cells. Since neutrophil chemotaxis and transmigration depends on endothelial cell activation, we aimed to explore whether recombinant MASP-1 (rMASP-1) is able to induce cytokine production and subsequent neutrophil chemotaxis in human umbilical vein endothelial cells (HUVEC). We found that HUVECs activated by rMASP-1 secreted IL-6 and IL-8, but not IL-1alpha, IL-1ra, TNFalpha and MCP-1. rMASP-1 induced dose-dependent IL-6 and IL-8 production with different kinetics. rMASP-1 triggered IL-6 and IL-8 production was regulated predominantly by the p38-MAPK pathway. Moreover, the supernatant of rMASP-1-stimulated HUVECs activated the chemotaxis of neutrophil granulocytes as an integrated effect of cytokine production. Our results implicate that besides initializing the complement lectin pathway, MASP-1 may activate neutrophils indirectly, via the endothelial cells, which link these effective antimicrobial host defense mechanisms

Both Positive and Negative Selection Pressures Contribute to the Polymorphism Pattern of the Duplicated Human CYP21A2 Gene.

The human steroid 21-hydroxylase gene (CYP21A2) participates in cortisol and aldosterone biosynthesis, and resides together with its paralogous (duplicated) pseudogene in a multiallelic copy number variation (CNV), called RCCX CNV. Concerted evolution caused by non-allelic gene conversion has been described in great ape CYP21 genes, and the same conversion activity is responsible for a serious genetic disorder of CYP21A2, congenital adrenal hyperplasia (CAH). In the current study, 33 CYP21A2 haplotype variants encoding 6 protein variants were determined from a European population. CYP21A2 was shown to be one of the most diverse human genes (HHe=0.949), but the diversity of intron 2 was greater still. Contrary to previous findings, the evolution of intron 2 did not follow concerted evolution, although the remaining part of the gene did. Fixed sites (different fixed alleles of sites in human CYP21 paralogues) significantly accumulated in intron 2, indicating that the excess of fixed sites was connected to the lack of effective non-allelic conversion and concerted evolution. Furthermore, positive selection was presumably focused on intron 2, and possibly associated with the previous genetic features. However, the positive selection detected by several neutrality tests was discerned along the whole gene. In addition, the clear signature of negative selection was observed in the coding sequence. The maintenance of the CYP21 enzyme function is critical, and could lead to negative selection, whereas the presumed gene regulation altering steroid hormone levels via intron 2 might help fast adaptation, which broadly characterizes the genes of human CNVs responding to the environment

Common Genetic Variants of the Human Steroid 21-Hydroxylase Gene (CYP21A2) Are Related to Differences in Circulating Hormone Levels

This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Hungarian Scientific Research Fund (OTKA, PD100648 (AP)) Technology Innovation Fund, National Developmental Agency (KTIA-AIK-2012-12-1-0010). AP is the recipient of a “Lendület” grant from the Hungarian Academy of Sciences

Szérum kromogranin A szint vizsgálata 2-es típusú cukorbetegségben [Serum chromogranin A level in patients with type 2 diabetes]

A kromogranin A (CgA) a granin fehérjecsaládba tartozó glükoprotein. E fehérje és a diabetes közötti szoros kapcsolatot 1-es típusú cukorbetegségben korábban több munkacsoport is igazolta. Jelen vizsgálatunk során a Semmelweis Egyetem, II. sz. Belgyógyászati Klinika Anyagcsere Ambulanciáján 2-es típusú cukorbetegek szérum kromogranin A szintjét határoztuk meg. Vizsgáltuk továbbá, hogy mely anamnesztikus és/vagy laboratóriumi paraméter függ össze a kromogranin A szinttel. Összesen 86 2-es típusú cukorbeteg személyt vontunk be a vizsgálatba. A betegekről felvett anamnesztikus adatok mellett éhgyomri vérvételt követően elemeztük a vérképet, a HbA1c-szintet, a vérzsírokat, a vesefunkciót, illetve a TSH-t. A szérum kromogranin A szint meghatározása radioimmunoassay módszerrel történt. A vizsgált személyek közül 6 főnél (6,98%) volt igazolható emelkedett szérum kromogranin A szint. A normális tartomány felső határértéke alapján 2 kohorszra osztottuk a betegeket (Normál CgA: 80 fő, szérum-CgA 50,43±21,73 ng/ml; Magas CgA: 6 fő, szérum-CgA 129,33±41,07 ng/ml; p<0,0001). A két vizsgálati kohorsz között sem a laboratóriumi paraméterekben, sem a HbA1c-értékekben, sem pedig az anamnesztikus adatokban nem igazoltunk különbséget. Eredményeink alapján 2-es típusú diabetesben a kromogranin A szint és a diabetes fennállási ideje, valamint az anyagcserehelyzet között nem igazolható összefüggés. | Chromogranin A (CgA) is a member of the granin glycoprotein family. Most important effects of the protein related to diabetes have been demonstrated in type 1 diabetes. In the present cohort study serum chromogranin A levels of patients with type 2 diabetes were analyzed, who attended the Metabolic Clinic of the 2nd Department of Internal Medicine, Semmelweis University. It was also investigated whether anamnestic or laboratory data has any relation to chromogranin A levels. Altogether 86 patients with type 2 diabetes were included. Anamnestic data were collected and fasting blood samples were taken. Complete blood count, HbA1c , lipids, renal function and TSH were analyzed. CgA values were measured via radioimmunoassay. At six of the 86 subjects (6,98%) had elevated serum chromogranin A levels. Patients were divided into two cohorts based on the serum CgA upper limit of normal (Normal CgA: 80 subjects, serum CgA 50,43±21,73 ng/ml; High CgA: 6 subjects, serum CgA 129,33±41,07 ng/ml; p<0,0001). No differences were found between study groups neither in laboratory parameters, nor in HbA1c values, nor in anamnestic data. Our results suggest that in type 2 diabetes there’s no connection between serum chromogranin A levels and the duration of diabetes, and it has no effect on glycemic control

A kromogranin-A szerepe diabetes mellitusban humán vizsgálatok és állatkísérletek alapján [The role of Chromogranin-A in diabetes mellitus based on human clinical and animal model studies]

A kromogranin-A a granin fehérjecsaládba tartozik, különböző szervek endokrin és neuroendokrin sejtjei termelik. Számos ismert vagy mind ez ideig kevésbé tisztázott funkciójú, kisebb fehérje hasad ki belőle. A klinikumban elsősorban a neuroendokrin sejtes daganatok kimutatására, illetve azok terápiás követésére alkalmazzák. A kromogranin-A és a cukorbetegség kapcsolatának vizsgálata friss kutatási terület. A fehérje diabetesben betöltött pontos szerepe egyelőre nem tisztázott, de erős kapcsolatra utal, hogy az 1-es típusú cukorbetegség modellállataiban, a nem-obes diabeteses egerekben, ha a kromogranin-A gént kiütötték, hím egereknél nem, míg nőstényekben is csak nagyon ritkán alakult ki a betegség, összehasonlítva a vad típusú, nem-obes diabeteses egerekkel. A pankreasztatin szabályozza a cukor-, zsír- és fehérje-anyagcserét a májban és a zsírszövetben. A WE-14 és további kromogranin-A-fragmentumok mind a humán klinikai vizsgálatok, mind egerekkel végzett állatkísérletek alapján a β-sejtek elpusztításában részt vevő CD4+ és CD8+ T-sejtek autoantigénjeiként funkcionálnak. Kontrollszemélyekhez képest a szérumban magasabb kromogranin-A-, pankresztatin- és WE-14-koncentrációkat mutattak ki mind 1-es típusú, mind 2-es típusú és gestatiós diabetesben szenvedő betegekben. A bemutatott adatok alapján a kromogranin-A a diabetes mellitus kialakulásában, patomechanizmusában fontos szerepet játszhat. Az eddigi ismeretek alapján a cukorbetegség és a fehérje további kapcsolatának vizsgálata szükséges. | Chromogranin-A, produced by the endocrine and neuroendocrine cells of different organs, is a family member of the granin proteins. It has cleavage products with well-known biological function, while the role of other products has not been fully understood yet. Its elevation in serum is currently used as a marker in the diagnostics of neuroendocrine cell originated tumors. The relationship between Chromogranin-A and diabetes mellitus is an ongoing research area. Its exact role in diabetes has not been clarified, but a notable connection has been inferred through type 1 diabetes mellitus is not developed in Chromogranin-A gene knockout male, non-obes diabetic mouse models, and it is sparsely observed in knockout female mice compared to wild type non-obese diabetic mice. The cleavage products pancreastatin and WE-14 are related to various types of diabetes. Pancreastatin has a regulatory function in the sugar, fat and protein metabolism of liver and adipose tissue. WE-14 and other small Chromogranin-A fragments are autoantigens for the β-cell destructive diabetogenic CD4+ and CD8+ T-cells in both human and non-obese diabetic mice. Higher Chromogranin-A, pancreastatin and WE-14 levels have been reported in type 1, type 2 and gestational diabetic patients than in healthy controls. Chromogranin-A may play an important role in the development and pathogenesis of diabetes mellitus according to the presented studies, and further studies are needed to investigate this relationship

Scale representation of the segregating sites of human <i>CYP21</i> genes.

<p>Boxes symbolize the exons, red indicates the coding region, pink shows the untranslated regions. Segregating sites are denoted by their position, numbered from the start of the <i>CYP21A2</i> coding region in the sequence NT_007592.15: 31945792-31949720. The segregating site of the <i>CYP21A2</i> gene can be seen above the depicted gene. The segregating site of the <i>CYP21A1P</i> gene derived from an external dataset can be found below the depicted gene.</p