CD200/CD200R are highly conserved type I paired membrane glycoproteins that belong to the Ig superfamily containing a two immunoglobulin‑like domain (V, C). CD200 is broadly distributed in a variety of cell types, whereas CD200R is primarily expressed in myeloid and lymphoid cells. They fulfill multiple functions in regulating inflammation. The interaction between CD200/CD200R results in activation of the intracellular inhibitory pathway with RasGAP recruitment and thus contributes to effector cell inhibition. It was confirmed that the CD200R activation stimulates the differentiation of T cells to the Treg subset, upregulates indoleamine 2,3‑dioxygenase activity, modulates cytokine environment from a Th1 to a Th2 pattern, and facilitates an antiinflammatory IL‑10 and TGF‑β synthesis. CD200/CD200R are required for maintaining self‑tolerance. Many studies have demonstrated the importance of CD200 in controlling autoimmunity, inflammation, the development and spread of cancer, hypersensitivity, and spontaneous fetal loss., Drahomíra Holmannová, Martina Koláčková, Kateřina Kondělková, Pavel Kuneš, Jan Krejsek, Ctirad Andrýs, and Literatura 46
Hypotonic solution alters ion channel activity, but little attention has been paid to voltage-dependent sodium channels. The aim of this study was to investigate the effects of hypotonic solution on transient sodium currents (INaT) and persistent sodium currents (INaP). We also explored whether the intracellular signal transduction systems participated in the hypotonic modifications of sodium currents. INaT and INaP were recorded by means of whole-cell patch-clamp technique in isolated rat ventricular myocytes. Our results revealed that hypotonic solution reduced INaT and simultaneously augmented INaP with the occurrence of interconversion between INaT and INaP. Hypotonic solution shifted steady-state inactivation to a more negative potential, prolonged the time of recovery from inactivation, and enhanced intermediate inactivation (IIM). Ruthenium red (RR, inhibitor of TRPV4), bisindolylmaleimide VI (BIM, inhibitor of PKC), Kn-93 (inhibitor of Ca/CaMKII) and BAPTA (Ca2+-chelator) inhibited the effects of hypotonic solution on INaT and INaP. Therefore we conclude that hypotonic solution inhibits INaT, enhances INaP and IIM with the effects being reversible. TRPV4 and intracellular Ca2+, PKC and Ca/CaMKII participate in the hypotonic modifications of sodium currents., L. Hu ... [et al.]., and Obsahuje seznam literatury
Ochorenia myelínu CNS sa súhrnne označujú ako leukoencefalopatie. Termín zahŕňa poruchy, pri ktorých zmeny v bielej hmote prevažujú alebo sú výlučné, pričom patofyziologický mechanizmus ani histopatologická báza nie sú rozhodujúce. Z tejto širokej skupiny vrodených a získaných porúch sa vyčleňuje skupina leukodystrofií, ktorá označuje primárnu poruchu myelínu a buniek tvoriacich myelín. Klasicky sa do tejto skupiny radí šesť klinických jednotiek: X‑adrenoleukodystrofia, metachromatická leukodystrofia, Krabbeho globoidná leukodystrofia, Canavanovej choroba, Pelizaeus‑Merzbacherova choroba a Alexandrova choroba. Pribúdajúcimi poznatkami sa skupina rozširuje o stále nové primárne poruchy. Pre presnú diagnostiku je dôležitý klinický nález, významné sú zmeny na MR mozgu a laboratórne vyšetrenia. Precíznou analýzou MR obrazu je možné diagnostický proces urýchliť. Jedným zo spoločných znakov leukodystrofií je progresívny priebeh. U detí nastáva zväčša rýchla strata motorických a kognitívnych funkcií. V prípade adolescentov a adultných pacientov je ťažisko zmien v psychickej a mentálnej oblasti, pričom motorický deficit nastupuje neskôr. Priebeh X‑adrenoleukodystrofie, metachromatickej leukodystrofie, Krabbeho globoidnej leukodystrofie sa dá vo včasnom štádiu alebo predklinickom období ovplyvniť transplantáciou kostnej drene alebo kmeňových buniek. V prípade metachromatickej leukodystrofie je v skorých štádiách indikovaná génová a enzýmová terapia. Pre ostatné leukodystrofie je dostupná len symptomatická liečba. Cieľom práce je zhrnutie najdôležitejších poznatkov a liečebných možností., Myelin disorders of the central nervous system are also known as leukoencephalopathies. This term includes diseases, in which changes of the white matter are dominant, or even exclusive, while neither the pathophysiological mechanism nor the histopathological basis are decisive. This broad selection of inborn and acquired disorders includes a group of leukodystrophies characterized by primary dysfunction of myelin and myelin-producing cells. Typically, six separate clinical entities are included in this group: X-linked adrenoleukodystrophy, metachromatic leukodystrophy, Krabbe’s globoid cell leukodystrophy, Canavan disease, Pelizaeus-Merzbacher disease and Alexander disease. The group is constantly expanding as our knowledge develops. Clinical and laboratory findings, as well as MRI scans, are crucial for exact diagnosis. Accurate analysis of MRI images accelerates the diagnostic process considerably. A common feature of leukodystrophies is their progressive nature. Children exhibit rapid loss of motor and cognitive functions. In adolescent and adult patients, psychological and mental changes are the most prominent, while motor deficit has a later onset. The course of X-linked adrenoleukodystrophy, metachromatic leukodystrophy, and Krabbe’s leukodystrophy can be managed at the early or pre-clinical stages with bone marrow or stem cell transplantation. Gene and enzyme therapy are indicated at the earliest stages of metachromatic leukodystrophy. For the remaining leukodystrophies, only symptomatic therapy is available. The purpose of this paper is to summarize current information and knowledge as well as possible therapeutic options in this group of disorders., Vědomostní test, and M. Kolníková, P. Sýkora
Chronické myeloproliferativní neoplázie (MPN) představují různorodou skupinu myeloidních neoplázií, jejichž molekulární podstata je charakterizovaná přítomností mutace JAK2V617F. Po tomto zásadním objevu bylo zjištěno několik dalších mutací, což jen zdůraznilo nečekanou molekulární složitost. Ústředním rysem MPN je deregulace dráhy JAK/STAT a i když vzbudila velký zájem vzhledem k možnosti cílené léčby inhibitory JAK2, dospělo se k závěru, že ve většině případů, ne-li ve všech, jsou mutace JAK2 sekundární mutační událostí. Další opakující se otázkou je postižení genů ovlivňujících epigenetickou kontrolu genové exprese a nově také sestřih (splicing) RNA. Většinu těchto mutací mají rovněž pacienti s myelodysplastickými syndromy. Studie zaměřené na složitou klonální hierarchii MPN svědčí o stavu genetické nestability, který by mohl být buď získaný, nebo dědičný. V tomto ohledu nám objevení specifického zárodečného haplotypu u JAK2 poskytlo vysvětlení jevu „familiárního clusteringu” MPN, přestože se na něm pravděpodobně podílejí i jiné, dosud neznámé haplotypy. Cílem tohoto přehledu je shrnout současné poznatky o molekulárních abnormalitách MPN a probrat jejich úlohu v diagnostice a prognóze., Chronic myeloproliferative neoplasms (MPNs) represent a heterogeneous group of myeloid neoplasia whose molecular asset is marked by the presence of a JAK2V617F mutation. Following this seminal discovery, several other mutations have been identified highlighting an unexpected molecular complexity. Deregulation of the JAK/STAT pathway is a central feature of MPNs and, although it has raised much interest for the possibility of targeted therapy with JAK2 inhibitors, it has been realized that JAK2 mutations are secondary mutational events in most, if not all, cases. Another recurrent theme is the involvement of genes intervening in the epigenetic control of gene expression and, more recently, in RNA splicing. Most of these mutations are shared by patients with myelodysplastic syndromes as well. Studies focusing on the complex clonal hierarchy of MPNs suggest a condition of genetic instability, that could be either acquired or inherited. At this regard, the discovery of a specific germline haplotype in JAK2 provided an explanation for the phenomenon of familial clustering of MPNs, although other still unknown haplotypes are likely involved. The aim of this review is to summarize current knowledge of molecular abnormalities of MPNs and discuss their role for diagnosis and prognosis., Alessandro M.Vannucchi, Paola Guglielmelli, and Literatura 95
Depression is a complex disorder related to chronic inflammatory processes, chronic stress changes and a hippocampal response. There is a increasing knowledge about the role of glial cells in nutrient supply to neurons, maintenance of synaptic contacts and tissue homeostasis within the CNS. Glial cells, viewed in the past as passive elements with a limited influence on neuronal function, are becoming recognized as active partners of neurons and are starting to be discussed as a possible therapeutic target. Their role in the pathogenesis of depressive disorders is also being reconsidered. Attention is devoted to studies of the different types of antidepressants and their effects on transmembrane signaling, including levels of α subunits of G proteins in C6 glioma cells in vitro as a model of postsynaptic changes in vivo. These models indicate similarities in antidepressant effects on G proteins of brain cells and effector cells of natural immunity, natural killers and granulocytes. Thus, an antidepressant response can exhibit certain common characteristics in functionally different systems which also participate in disease pathogenesis. There are, however, differences in the astrocyte G-protein responses to antidepressant treatment, indicating that antidepressants differ in their effect on glial signalization. Today mainstream approach to neurobiological basis of depressive disorders and other mood illnesses is linked to abnormalities in transmembrane signal transduction via G-protein coupled receptors. Intracellular signalization cascade modulation results in the activation of transcription factors with subsequent increased production of a wide array of products including growth factors and to changes in cellular activity and reactivity., M. Páv, H. Kovářů, A. Fišerová, E. Havrdová, V. Lisá., and Obsahuje bibliografii a bibliografické odkazy
Receptor pro konečné produkty pokročilé glykace hraje významnou roli v rozvoji chronických diabetických komplikací. Ukazuje se, že zasahuje více či méně do všech typů diabetické angiopatie. Hlavním jeho ligandem jsou samotné konečné produkty pokročilé glykace (AGEs), které se ve vyšší míře u diabetiků akumulují, ale v posledním desetiletí jsou známy i silnější aktivátory tohoto receptoru, tzv. alarminy. Ty se jinak uplatňují v rozvoji zánětlivé reakce organizmu. Aktivovaný RAGE spouští kaskádu dějů vedoucích k dalšímu hromadění AGEs a kyslíkových radikálů, a navíc je cestou NF-κB iniciována chronická zánětlivá odpověď organizmu. Centrální úloha RAGE v patogenezi cévních změn dělá z tohoto receptoru slibné místo možného budoucího terapeutického či preventivního zásahu. Klíčová slova: diabetes mellitus – hyperglykemie – konečné produkty pokročilé glykace – makroangiopatie – mikroangiopatie – metylglyoxal – receptor konečných produktů pokročilé glykace, Receptor for advanced glycation end-products plays a crucial role in chronic diabetes complications. It is supposed to be involved in the development of all kinds of diabetic angiopathy. Advanced glycation end-products (AGEs) excessively accumulated in diabetes belong to the most important ligands of RAGE, however there are more potent activators of this receptor – especially alarmins, often involved in inflammatory reactions. Activated RAGE triggers pathways leading to excessive accumulation of AGEs, reactive oxygen species and sustained inflammatory reactions via NF-κB. Central role of RAGE in the pathogenesis of vascular changes in diabetes represents suitable target for new therapeutic or preventive approach. Key words: advanced glycation end-products – diabetes mellitus – hyperglycaemia – macroangiopathy – methylglyoxal – microangiopathy – receptor for advanced glycation end-products, and Jan Škrha Jr, Marta Kalousová, Tomáš Zima