Humán adipociták “browning”-folyamatát kiváltó szerek azonosítása; Populációs-szintű sejtes vizsgálatok kialakítása

Munkánk során statisztikailag releváns számú, differenciálódott humán adipocita vizsgálatát a Lézer Pásztázó Citométer (LSC) alkalmazásával értük el. Az LSC használata lehetővé tette számukra az adherens adipociták multiparametrikus vizsgálatát: a sejtek festése nélkül kvantifikáltuk az adipocitákban lévő lipid cseppek számát és méretét (ún. texture analízissel), majd a sejtek fixálását és permeabilizálását követően jelöltük az Ucp1 és Cidea barna zsírsejt marker fehérjéket, specifikus antitestekkel. Megfigyeltük, hogy mind az irisin, mind a BMP7 alkalmazása a fehér differenciációs protokoll alatt fokozta az UCP1 és CIDEA mellett az ELOVL3, CYC1 és PGC-1α általános barna zsírsejt marker gének kifejeződését. A ZIC1 („klasszikus barna” marker) emelkedett kifejeződését figyeltük meg, hosszú távú BMP7 kezelés hatására. A TBX1 „beige” marker gén kifejeződését ugyanakkor csak az irisin kezelés fokozta. A második generációs antipszichotikumok alkalmazása gyakran vezet elhízáshoz. Humán szövetből izolált preadipociták clozapine kezelése ennek ellenére a barna és “beige” marker gének legtöbbjének, illetve az Ucp1 fehérje kifejeződését szignifikánsan fokozta, míg a fehér és általános zsírszöveti marker gének kifejeződése a kezelés hatására nem változott. A clozapine kezelés képes volt “beige” zsírsejt differenciáció iniciálására humán ex vivo rendszerben, azonban az így létrejött sejtek reakciója természetes hőképző stimulusokra csökkent. A barna marker gének fokozott kifejeződése clozapine hatására, szerotonin (5HT) jelenlétében ugyanakkor nem volt megfigyelhető. Eredményeink arra utalnak, hogy a clozapine “browning”-ot kiváltó hatása összefügg a szer 5HT receptorok által kiváltott jelátvitel-gátló képességével. Végül megfigyeltük, hogy az ex vivo differenciáltatott barna zsírsejtek és irisin kezelt fehér zsírsejtek nagymértékben termelnek IL-6, IL-8 és MCP-1 citokineket.By complementing measurements of gene expression changes from total cell lysates, Laser-scanning cytometry (LSC) was presented as a tool that made the population scale analysis of ex vivo browning possible. Our approach combined texture analysis which reflected the size and number of lipid droplets and detection of Ucp1 and Cidea protein content in single browning adipocytes of mixed cell populations. Irisin administration during white adipogenic differentiation resulted in a significant upregulation of several brown and “beige” adipocyte marker genes. Irisin treated cells had smaller lipid droplets, more mitochondrial DNA, higher mitochondrial respiration and contained more Ucp1 and Cidea protein than the untreated white adipocytes. On the contrary, BMP7 treatment resulted in a functional browning in parallel with the gene expression pattern which indicated the “classical brown” program. We unexpectedly observed that clozapine reprogrammed the gene expression pattern of differentiating human adipocytes ex vivo, leading to an elevated expression of the browning marker gene UCP1, more and smaller lipid droplets and more mitochondrial DNA than in the untreated white adipocytes. Furthermore, clozapine significantly up-regulated TBX1 gene but not ZIC1 suggesting induction of the “beige”-like and not the “classical brown” phenotype. The clozapine induced “beige” cells displayed increased basal and oligomycin inhibited (proton leak) oxygen consumption but these cells showed a lower response to cAMP stimulus as compared to control “beige” adipocytes. The disturbance of 5HT-receptor-mediated signaling by clozapine might, at least partially, explain the browning effect of the drug. Finally, when conditioned differentiation media were collected during the replacement of the adipogenic cocktails, we found that IL-6, MCP-1 and IL-8 secretion was significantly higher by “beige” compared to white adipocytes

Unique key Horn functions

Given a relational database, a key is a set of attributes such that a value assignment to this set uniquely determines the values of all other attributes. The database uniquely defines a pure Horn function $h$, representing the functional dependencies. If the knowledge of the attribute values in set $A$ determines the value for attribute $v$, then $A\rightarrow v$ is an implicate of $h$. If $K$ is a key of the database, then $K\rightarrow v$ is an implicate of $h$ for all attributes $v$. Keys of small sizes play a crucial role in various problems. We present structural and complexity results on the set of minimal keys of pure Horn functions. We characterize Sperner hypergraphs for which there is a unique pure Horn function with the given hypergraph as the set of minimal keys. Furthermore, we show that recognizing such hypergraphs is co-NP-complete already when every hyperedge has size two. On the positive side, we identify several classes of graphs for which the recognition problem can be decided in polynomial time. We also present an algorithm that generates the minimal keys of a pure Horn function with polynomial delay. By establishing a connection between keys and target sets, our approach can be used to generate all minimal target sets with polynomial delay when the thresholds are bounded by a constant. As a byproduct, our proof shows that the Minimum Key problem is at least as hard as the Minimum Target Set Selection problem with bounded thresholds.Comment: 12 pages, 5 figure

Futures Studies in the Interactive Society

This book consists of papers which were prepared within the framework of the research project (No. T 048539) entitled Futures Studies in the Interactive Society (project leader: Éva Hideg) and funded by the Hungarian Scientific Research Fund (OTKA) between 2005 and 2009. Some discuss the theoretical and methodological questions of futures studies and foresight; others present new approaches to or procedures of certain questions which are very important and topical from the perspective of forecast and foresight practice. Each study was conducted in pursuit of improvement in futures fields

Laser-scanning cytometry can quantify human adipocyte browning and proves effectiveness of irisin

Laser-scanning cytometry is presented as a tool allowing population scale analysis of ex vivo human brown adipogenic differentiation. It combines texture analysis and detection of Ucp1 protein content in single brown adipocytes of mixed cell populations with gene expression pattern and functional characteristics of browning. Using this method we could validate mouse data in human samples demonstrating the effectiveness of irisin to induce “beige” differentiation of subcutaneous white adipocytes.EUR 1,165 APC fee funded by the EC FP7 Post-Grant Open Access Pilo