Publikace se zaměřuje na evoluční vývoj buňky, cytologii a související genetické a membránové procesy. Určeno široké veřejnosti.; Kniha se věnuje zkoumání buňky z různých úhlů pohledu.Postupně seznamuje se základními vlastnostmi živé hmoty, životními formami, evolucí a vznikem života, vlastnostmi a původem molekul, tvořících stavební prvky buněčného těla, fyzikálně-chemickými principy podstatnými pro fungování buněčného mechanismu, významem a funkcí biologických membrán, metabolismem, transportem, signalizací a získáváním energie pro životní procesy, aby v závěru vyvrcholil charakteristikou eukaryotických buněk, které jsou podstatou všech mnohobuněčných organismů, včetně člověka. Významnou část knihy tvoří kapitoly věnované světu nukleových kyselin, zejména RNA a DNA, uchovávajících genetickou informaci ve formě genetického kódu, a syntéze proteinů, součástí buněk veškerých živých organismů. Kniha je doplněna množstvím názorných schémat a obrázků.

• MeSH
• biologická evoluce MeSH
• biologie buňky MeSH
• genetika MeSH
• membrány MeSH
• molekulární biologie * MeSH
• Publikační typ
• monografie MeSH
• populární práce MeSH

• Konspekt
• Biochemie. Molekulární biologie. Biofyzika
• NLK Obory
• biologie
• molekulární biologie, molekulární medicína

BACKGROUND: Early-life stress in the form of maternal separation can be associated with alterations in offspring neurodevelopment and brain functioning. Here, we aimed to investigate the potential impact of prolonged maternal separation on proteomic profiling of prefrontal cortex, hippocampus and cerebellum of juvenile and young adult rats. A special attention was devoted to proteins involved in the process of cell death and redox state maintenance. METHODS: Long-Evans pups were separated from their mothers for 3 h daily over the first 3 weeks of life (during days 2-21 of age). Brain tissue samples collected from juvenile (22-day-old) and young adult (90-day-old) rats were used for label-free quantitative (LFQ) proteomic analysis. In parallel, selected oxidative stress markers and apoptosis-related proteins were assessed biochemically and by Western blot, respectively. RESULTS: In total, 5526 proteins were detected in our proteomic analysis of rat brain tissue. Approximately one tenth of them (586 proteins) represented those involved in cell death processes or regulation of oxidative stress balance. Prolonged maternal separation caused changes in less than half of these proteins (271). The observed alterations in protein expression levels were age-, sex- and brain region-dependent. Interestingly, the proteins detected by mass spectrometry that are known to be involved in the maintenance of redox state were not markedly altered. Accordingly, we did not observe any significant differences between selected oxidative stress markers, such as the levels of hydrogen peroxide, reduced glutathione, protein carbonylation and lipid peroxidation in brain samples from rats that underwent maternal separation and from the corresponding controls. On the other hand, a number of changes were found in cell death-associated proteins, mainly in those involved in the apoptotic and autophagic pathways. However, there were no detectable alterations in the levels of cleaved products of caspases or Bcl-2 family members. Taken together, these data indicate that the apoptotic and autophagic cell death pathways were not activated by maternal separation either in adolescent or young adult rats. CONCLUSION: Prolonged maternal separation can distinctly modulate expression profiles of proteins associated with cell death pathways in prefrontal cortex, hippocampus and cerebellum of juvenile rats and the consequences of early-life stress may last into adulthood and likely participate in variations in stress reactivity.

• MeSH
• buněčná smrt * MeSH
• krysa rodu rattus MeSH
• maternální deprivace * MeSH
• mozek patofyziologie   MeSH
• novorozená zvířata MeSH
• potkani Long-Evans MeSH
• proteom * MeSH
• proteomika MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND AND PURPOSE: The aim of this study was to develop potent and long-acting antagonists of muscarinic ACh receptors. The 4-hexyloxy and 4-butyloxy derivatives of 1-[2-(4-oxidobenzoyloxy)ethyl]-1,2,3,6-tetrahydropyridin-1-ium were synthesized and tested for biological activity. Antagonists with long-residence time at receptors are therapeutic targets for the treatment of several neurological and psychiatric human diseases. Their long-acting effects allow for reduced daily doses and adverse effects. EXPERIMENTAL APPROACH: The binding and antagonism of functional responses to the agonist carbachol mediated by 4-hexyloxy compounds were investigated in CHO cells expressing individual subtypes of muscarinic receptors and compared with 4-butyloxy analogues. KEY RESULTS: The 4-hexyloxy derivatives were found to bind muscarinic receptors with micromolar affinity and antagonized the functional response to carbachol with a potency ranging from 30 nM at M1 to 4 μM at M3 receptors. Under washing conditions to reverse antagonism, the half-life of their antagonistic action ranged from 1.7 h at M2 to 5 h at M5 receptors. CONCLUSIONS AND IMPLICATIONS: The 4-hexyloxy derivatives were found to be potent long-acting M1 -preferring antagonists. In view of current literature, M1 -selective antagonists may have therapeutic potential for striatal cholinergic dystonia, delaying epileptic seizure after organophosphate intoxication or relieving depression. These compounds may also serve as a tool for research into cognitive deficits.

• MeSH
• antagonisté muskarinových receptorů chemická syntéza   chemie   farmakologie   MeSH
• CHO buňky MeSH
• Cricetulus MeSH
• karbachol chemie   farmakologie   MeSH
• kultivované buňky MeSH
• molekulární struktura MeSH
• pyridiny chemická syntéza   chemie   farmakologie   MeSH
• receptory muskarinové metabolismus   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• vztahy mezi strukturou a aktivitou MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Xanomeline (3-(Hexyloxy)-4-(1-methyl-1,2,5,6-tetrahydropyridin-3-yl)-1,2,5-thiadiazole) is a muscarinic agonist that is considered to be functionally selective for the M1/M4 receptor subtypes. Part of xanomeline binding is resistant to washing. Wash-resistant xanomeline activates muscarinic receptors persistently, except for the M5 subtype. Mutation of leucine 6.46 to isoleucine at M1 or M4 receptors abolished persistent activation by wash-resistant xanomeline. Reciprocal mutation of isoleucine 6.46 to leucine at the M5 receptor made it sensitive to activation by wash-resistant xanomeline. Lowering of membrane cholesterol made M1 and M4 mutants and M5 wild type receptors sensitive to activation by wash-resistant xanomeline. Molecular docking revealed a cholesterol binding site in the groove between transmembrane helices 6 and 7. Molecular dynamics showed that interaction of cholesterol with this binding site attenuates receptor activation. We hypothesize that differences in cholesterol binding to this site between muscarinic receptor subtypes may constitute the basis for xanomeline apparent functional selectivity and may have notable therapeutic implications. Differences in receptor-membrane interactions, rather than in agonist-receptor interactions, represent a novel possibility to achieve pharmacological selectivity. Our findings may be applicable to other G protein coupled receptors.

• MeSH
• agonisté muskarinových receptorů farmakokinetika   MeSH
• buněčná membrána účinky léků   metabolismus   MeSH
• CHO buňky cytologie   MeSH
• cholesterol metabolismus   MeSH
• Cricetulus MeSH
• inositolfosfáty metabolismus   MeSH
• magnetická rezonanční spektroskopie MeSH
• molekulární modely MeSH
• průtoková cytometrie MeSH
• pyridiny farmakokinetika   MeSH
• radioligandová zkouška MeSH
• receptory muskarinové genetika   metabolismus   MeSH
• simulace molekulového dockingu MeSH
• thiadiazoly farmakokinetika   MeSH
• tritium farmakokinetika   MeSH
• vápník metabolismus   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Muscarinc receptor-mediated signaling takes part in many physiological functions ranging from complex higher nervous activity to vegetative responses. Specificity of action of the natural muscarinic agonist acetylcholine is effected by action on five muscarinic receptor subtypes with particular tissue and cellular localization, and coupling preference with different G-proteins and their signaling pathways. In addition to physiological roles it is also implicated in pathologic events like promotion of carcinoma cells growth, early pathogenesis of neurodegenerative diseases in the central nervous system like Alzheimer's disease and Parkinson's disease, schizophrenia, intoxications resulting in drug addiction, or overactive bladder in the periphery. All of these disturbances demonstrate involvement of specific muscarinic receptor subtypes and point to the importance to develop selective pharmacotherapeutic interventions. Because of the high homology of the orthosteric binding site of muscarinic receptor subtypes there is virtually no subtype selective agonist that binds to this site. Activation of specific receptor subtypes may be achieved by developing allosteric modulators of acetylcholine binding, since ectopic binding domains on the receptor are less conserved compared to the orthosteric site. Potentiation of the effects of acetylcholine by allosteric modulators would be beneficial in cases where acetylcholine release is reduced due to pathological conditions. When presynaptic function is severely compromised, the utilization of ectopic agonists can be a thinkable solution.

• MeSH
• agonisté muskarinových receptorů terapeutické užití   MeSH
• antagonisté muskarinových receptorů terapeutické užití   MeSH
• lidé MeSH
• nemoci nervového systému farmakoterapie   metabolismus   MeSH
• neurony účinky léků   metabolismus   MeSH
• receptory muskarinové účinky léků   metabolismus   MeSH
• signální transdukce účinky léků   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

We investigated the functional characteristics of pre- and postsynaptic cholinergic transmission in APPswe/PS1dE9 double transgenic mice at a young age (7-10 weeks) before the onset of amyloid plaque formation and at adult age (5-6 months) at its onset. We compared brain slices from cerebral cortex and hippocampus with amyloid deposits to slices from striatum with no amyloid plaques by 6 months of age. In young transgenic mice we found no impairments of preformed and newly synthesized [(3)H]-ACh release, indicating intact releasing machinery and release turnover, respectively. Adult transgenic mice displayed a significant increase in preformed [(3)H]-ACh release in cortex but a decrease in hippocampus and striatum. The extent of presynaptic muscarinic autoregulation was unchanged. Evoked release of newly synthesized [(3)H]-ACh was significantly reduced in the cortex and hippocampus but unchanged in the striatum. Carbachol-induced G-protein activation in cortical membranes displayed decreased potency but normal efficacy in adult animals and no changes in young animals. These results indicate that functional pre- and postsynaptic cholinergic deficits are not present in APPswe/PS1dE9 transgenic mice before 10 weeks of age, but develop along with beta-amyloid accumulation in the brain.

• MeSH
• acetylcholin nedostatek   MeSH
• Alzheimerova nemoc genetika   metabolismus   patofyziologie   MeSH
• amyloid metabolismus   MeSH
• amyloidový prekurzorový protein beta genetika   MeSH
• cholinergní agonisté farmakologie   MeSH
• cholinergní vlákna metabolismus   patologie   MeSH
• degenerace nervu metabolismus   patologie   MeSH
• down regulace genetika   MeSH
• hipokampus metabolismus   patologie   patofyziologie   MeSH
• modely nemocí na zvířatech MeSH
• mozek - chemie genetika   MeSH
• mozek růst a vývoj   metabolismus   patofyziologie   MeSH
• mozková kůra růst a vývoj   metabolismus   patofyziologie   MeSH
• myši transgenní MeSH
• myši MeSH
• orgánové kultury - kultivační techniky MeSH
• presenilin-1 genetika   MeSH
• proteiny vázající GTP účinky léků   genetika   metabolismus   MeSH
• receptory muskarinové metabolismus   MeSH
• stárnutí metabolismus   MeSH
• věkové faktory MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

We investigated the influence of membrane cholesterol content on preferential and non-preferential signaling through the M(2) muscarinic acetylcholine receptor expressed in CHO cells. Cholesterol depletion by 39% significantly decreased the affinity of M(2) receptors for [(3)H]-N-methylscopolamine ([(3)H]-NMS) binding and increased B(max) in intact cells and membranes. Membranes displayed two-affinity agonist binding sites for carbachol and cholesterol depletion doubled the fraction of high-affinity binding sites. In intact cells it also reduced the rate of agonist-induced receptor internalization and changed the profile of agonist binding from a single site to two affinity states. Cholesterol enrichment by 137% had no effects on carbachol E(max) of cAMP synthesis inhibition and on cAMP synthesis stimulation and inositolphosphates (IP) accumulation at higher agonist concentrations (non-preferred pathways). On the other hand, cholesterol depletion significantly increased E(max) of cAMP synthesis inhibition or stimulation without change in potency, and decreased E(max) of IP accumulation. Noteworthy, modifications of membrane cholesterol had no effect on membrane permeability, oxidative activity, protein content, or relative expression of G(s), G(i/o), and G(q/11) alpha subunits. These results demonstrate distinct changes of M(2) receptor signaling through both preferential and non-preferential G-proteins consequent to membrane cholesterol depletion that occur at the level of receptor/G-protein/effector protein interactions in the cell membrane. The significant decrease of IP accumulation by cholesterol depletion was also observed in cells expressing M(3) receptors and by both cholesterol depletion and enrichment in cells expressing M(1) receptors indicating relevance of reduced G(q/11) signaling for the pathogenesis of Alzheimer's disease.

• MeSH
• acetylcholin analogy a deriváty   MeSH
• antagonisté muskarinových receptorů farmakologie   MeSH
• beta-cyklodextriny farmakologie   MeSH
• buněčná membrána metabolismus   účinky léků   MeSH
• CHO buňky MeSH
• cholesterol metabolismus   MeSH
• Cricetulus MeSH
• karbachol analogy a deriváty   farmakologie   metabolismus   MeSH
• křečci praví MeSH
• lidé MeSH
• N-methylskopolamin farmakologie   metabolismus   MeSH
• proteiny vázající GTP metabolismus   MeSH
• receptor muskarinový M2 metabolismus   MeSH
• systémy druhého messengeru účinky léků   MeSH
• zvířata MeSH
• Check Tag
• křečci praví MeSH
• lidé MeSH
• zvířata MeSH
• Publikační typ
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

BACKGROUND: Heterotrimeric guanine nucleotide-binding proteins (G proteins) play an essential role in linking cell-surface receptors to effector proteins at the plasma membrane. The functional activities of G proteins in various plasma membrane compartments remain to be elucidated.

• MeSH
• adenylátcyklasy MeSH
• aktivace enzymů MeSH
• baklofen farmakologie   MeSH
• buněčná membrána metabolismus   MeSH
• buněčné linie MeSH
• elektroforéza v polyakrylamidovém gelu MeSH
• financování organizované MeSH
• GTP-fosfohydrolasy metabolismus   MeSH
• guanosin 5'-O-(3-thiotrifosfát) metabolismus   MeSH
• krysa rodu rattus MeSH
• lidé MeSH
• mozková kůra enzymologie   metabolismus   MeSH
• potkani Wistar MeSH
• proteiny vázající GTP agonisté   metabolismus   MeSH
• western blotting MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• lidé MeSH
• mužské pohlaví MeSH
• zvířata MeSH

Agonist-induced subcellular redistribution of G-protein coupled receptors (GPCR) and of trimeric guanine-nucleotide binding regulatory proteins (G-proteins) represent mechanisms of desensitization of hormone response, which have been studied in our laboratory since 1989. This review brings a short summary of these results and also presents information about related literature data covering at least small part of research carried out in this area. We have also mentioned sodium plus potassium dependent adenosine triphosphatase (Na, K-ATPase) and 3H-ouabain binding as useful reference standard of plasma membrane purity in the brain.

• MeSH
• buněčná membrána enzymologie   metabolismus   MeSH
• down regulace MeSH
• heterotrimerní G-proteiny chemie   metabolismus   MeSH
• hormony metabolismus   MeSH
• křečci praví MeSH
• krysa rodu rattus MeSH
• mozek metabolismus   MeSH
• multimerizace proteinu MeSH
• proteiny vázající GTP chemie   metabolismus   MeSH
• receptory spřažené s G-proteiny metabolismus   MeSH
• signální transdukce fyziologie   MeSH
• sodíko-draslíková ATPasa metabolismus   MeSH
• subcelulární frakce metabolismus   MeSH
• zvířata MeSH
• Check Tag
• křečci praví MeSH
• krysa rodu rattus MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

• Publikační typ
• abstrakt z konference MeSH