Disordered motility is one of the most important pathogenic characteristics of functional dyspepsia (FD), although the underlying mechanisms remain unclear. Since the sympathetic system is important to the regulation of gastrointestinal motility, the present study aimed to investigate the role of norepinephrine (NE) and adrenoceptors in disordered gastric motility in a rat model with FD. The effect of exogenous NE on gastric motility in control and FD rats was measured through an organ bath study. The expression and distribution of beta-adrenoceptors were examined by real-time PCR, Western blotting and immunofluorescence. The results showed that endogenous gastric NE was elevated in FD rats, and hyperreactivity of gastric smooth muscle to NE and delayed gastric emptying were observed in the rat model of FD. The mRNA levels of beta1-adrenoceptor and norepinephrine transporter (NET) and the protein levels of beta2-adrenoceptor and NET were increased significantly in the gastric corpus of FD rats. All three subtypes of beta-adrenoceptors were abundantly distributed in the gastric corpus of rats. In conclusion, the enhanced NE and beta-adrenoceptors and NETs may be contributed to the disordered gastric motility in FD rats.

• MeSH
• beta-adrenergní receptory metabolismus   MeSH
• dyspepsie metabolismus   patofyziologie   MeSH
• modely nemocí na zvířatech MeSH
• noradrenalin metabolismus   MeSH
• potkani Sprague-Dawley MeSH
• proteiny přenášející noradrenalin přes plazmatickou membránu metabolismus   MeSH
• vyprazdňování žaludku * MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Currently, the diagnosis and treatment of neuroblastomas-the most frequent solid tumors in children-exploit the norepinephrine transporter (hNET) via radiolabeled norepinephrine analogs. We aim to develop a nanomedicine-based strategy towards precision therapy by targeting hNET cell-surface protein with hNET-derived homing peptides. RESULTS: The peptides (seq. GASNGINAYL and SLWERLAYGI) were shown to bind high-resolution homology models of hNET in silico. In particular, one unique binding site has marked the sequence and structural similarities of both peptides, while most of the contribution to the interaction was attributed to the electrostatic energy of Asn and Arg (< - 228 kJ/mol). The peptides were comprehensively characterized by computational and spectroscopic methods showing ~ 21% β-sheets/aggregation for GASNGINAYL and ~ 27% α-helix for SLWERLAYGI. After decorating 12-nm ferritin-based nanovehicles with cysteinated peptides, both peptides exhibited high potential for use in actively targeted neuroblastoma nanotherapy with exceptional in vitro biocompatibility and stability, showing minor yet distinct influences of the peptides on the global expression profiles. Upon binding to hNET with fast binding kinetics, GASNGINAYLC peptides enabled rapid endocytosis of ferritins into neuroblastoma cells, leading to apoptosis due to increased selective cytotoxicity of transported payload ellipticine. Peptide-coated nanovehicles significantly showed higher levels of early apoptosis after 6 h than non-coated nanovehicles (11% and 7.3%, respectively). Furthermore, targeting with the GASNGINAYLC peptide led to significantly higher degree of late apoptosis compared to the SLWERLAYGIC peptide (9.3% and 4.4%, respectively). These findings were supported by increased formation of reactive oxygen species, down-regulation of survivin and Bcl-2 and up-regulated p53. CONCLUSION: This novel homing nanovehicle employing GASNGINAYLC peptide was shown to induce rapid endocytosis of ellipticine-loaded ferritins into neuroblastoma cells in selective fashion and with successful payload. Future homing peptide development via lead optimization and functional analysis can pave the way towards efficient peptide-based active delivery of nanomedicines to neuroblastoma cells.

• MeSH
• antitumorózní látky chemie   farmakokinetika   farmakologie   MeSH
• endocytóza genetika   MeSH
• ferritin chemie   MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• nanomedicína MeSH
• nanostruktury chemie   MeSH
• neuroblastom metabolismus   MeSH
• peptidy chemie   genetika   metabolismus   MeSH
• proteiny přenášející noradrenalin přes plazmatickou membránu * chemie   genetika   metabolismus   MeSH
• systémy cílené aplikace léků metody   MeSH
• viabilita buněk účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

This study aimed to investigate the effects of chronic restraint stress (CRS) on the protein levels of dopamine-β-hydroxylase (DBH), noradrenaline transporter (NET), vesicular monoamine transporter 2 (VMAT2) and brain-derived neurotrophic factor (BDNF), as well as the concentration of noradrenaline (NA) in the rat hippocampus. The investigated parameters were quantified by Western blot analyses and ELISA kits. We found that CRS increased the protein levels of DBH by 30 %, VMAT2 by 11 %, BDNF by 11 % and the concentration of NA by 104 %, but decreased the protein levels of NET by 16 % in the hippocampus of chronically stressed rats. The molecular mechanisms by which CRS increased the hippocampal NA level are an important adaptive phenomenon of the noradrenergic system in the stress condition.

• MeSH
• dopamin-beta-hydroxylasa metabolismus   MeSH
• fyzické omezení MeSH
• hipokampus metabolismus   MeSH
• krysa rodu rattus MeSH
• mozkový neurotrofický faktor metabolismus   MeSH
• noradrenalin metabolismus   MeSH
• proteiny přenášející noradrenalin přes plazmatickou membránu metabolismus   MeSH
• psychický stres metabolismus   MeSH
• vezikulární transportní proteiny monoaminů metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

The human dopamine, norepinephrine, and serotonin transporters (hDAT, hNET, and hSERT) are carriers of neurotransmitters and targets for many drugs. Pioneering works in the past three years to elucidate experimental models of the Drosophila dDAT and human hSERT structures will rapidly impact the field of neuroscience. Here, we evaluated automated homology-based human models of these transporters, employing systematic physics-based, knowledge-based, and empirical-based check. Modeling guidelines were conveyed with attention to the central binding site (S1), secondary binding site (S2), and the extracellular loops EL2 and EL4. Application of new experimental models (dDAT and hSERT) will improve the accuracy of homology models, previously utilizing prokaryotic leucine transporter (LeuT) structure, and provide better predictions of ligand interactions, which is required for understanding of cellular mechanisms and for development of novel therapeutics.

• MeSH
• acetyltransferasy genetika   metabolismus   MeSH
• Drosophila MeSH
• konformace proteinů MeSH
• lidé MeSH
• membránové transportní proteiny pro serotonin genetika   metabolismus   MeSH
• molekulární modely * MeSH
• proteiny Drosophily genetika   metabolismus   MeSH
• proteiny přenášející dopamin přes plazmatickou membránu genetika   metabolismus   MeSH
• proteiny přenášející noradrenalin přes plazmatickou membránu genetika   metabolismus   MeSH
• rozpoznávání automatizované MeSH
• sekvenční homologie aminokyselin * MeSH
• vazebná místa MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• hodnotící studie MeSH

The colorectum (late distal colon) is innervated by the sympathetic nervous system, and many colorectal diseases are related to disorders of the sympathetic nervous system. The sympathetic regulation of colorectal ion transport is rarely reported. The present study aims to investigate the effect of norepinephrine (NE) in the normal and catecholamine-depleted condition to clarify the regulation of the sympathetic adrenergic system in ion transport in the rat colorectum. NE-induced ion transport in the rats colorectum was measured by short-circuit current (I(sc)) recording; the expression of beta-adrenoceptors and NE transporter (NET) were quantified by real-time PCR, and western blotting. When the endogenous catecholamine was depleted by reserpine, the baseline I(sc) in the colorectum was increased significantly comparing to controls. NE evoked downward deltaI(sc) in colorectum of treated rats was 1.8-fold of controls. The expression of beta(2)-adrenoceptor protein in the colorectal mucosa was greater than the control, though the mRNA level was reduced. However, NET expression was significantly lower in catecholamine-depleted rats compared to the controls. In conclusion, the sympathetic nervous system plays an important role in regulating basal ion transport in the colorectum. Disorders of sympathetic neurotransmitters result in abnormal ion transport, beta-adrenoceptor and NET are involved in the process.

• MeSH
• beta-2-adrenergní receptory genetika   metabolismus   MeSH
• časové faktory MeSH
• epitelové buňky metabolismus   MeSH
• inhibitory vychytávání adrenergních neurotransmiterů farmakologie   MeSH
• iontový transport MeSH
• kolon inervace   metabolismus   MeSH
• membránové potenciály MeSH
• messenger RNA metabolismus   MeSH
• noradrenalin metabolismus   farmakologie   MeSH
• potkani Sprague-Dawley MeSH
• proteiny přenášející noradrenalin přes plazmatickou membránu genetika   metabolismus   MeSH
• střevní sliznice inervace   metabolismus   MeSH
• sympatický nervový systém účinky léků   fyziologie   MeSH
• sympatomimetika farmakologie   MeSH
• techniky in vitro MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

• MeSH
• antidepresiva * farmakokinetika   farmakologie   terapeutické užití   MeSH
• deprese * etiologie   farmakoterapie   patofyziologie   MeSH
• dopaminergní neurony * účinky léků   MeSH
• léková rezistence * MeSH
• lidé MeSH
• membránové transportní proteiny pro serotonin * metabolismus   účinky léků   MeSH
• proteiny přenášející dopamin přes plazmatickou membránu * metabolismus   účinky léků   MeSH
• proteiny přenášející noradrenalin přes plazmatickou membránu * metabolismus   účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• práce podpořená grantem MeSH