cART Dotaz Zobrazit nápovědu
The cocaine- and amphetamine-regulated transcript (CART) peptide is a brain-born and brain-acting neuropeptide with anorexigenic properties. Production of the CART peptide in the brain is regulated by the anorexigenic hormone leptin. The CART peptide acts synergistically with the anorexigenic gut hormone cholecystokinin in attenuating food intake and neuron activation. A compact structure of the CART peptide with three disulfide bridges does not permit to make the biologically active molecule shorter; only one disulfide bridge can be omitted without losing biological activity. So far the CART peptide receptor has not been identified.
- Klíčová slova
- cocaine- and amphetamine-regulated transcript,
- MeSH
- cholecystokinin fyziologie MeSH
- energetický metabolismus účinky léků MeSH
- farmacie metody trendy MeSH
- genetická transkripce MeSH
- homeostáza účinky léků MeSH
- látky proti obezitě farmakologie chemie terapeutické užití MeSH
- leptin fyziologie MeSH
- lidé MeSH
- neurony fyziologie MeSH
- neuropeptidy farmakokinetika farmakologie genetika chemie MeSH
- obezita * prevence a kontrola MeSH
- přijímání potravy účinky léků MeSH
- proteiny nervové tkáně chemie MeSH
- regulace chuti k jídlu * účinky léků MeSH
- výzkum MeSH
- vztahy mezi strukturou a aktivitou MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
Celiac disease (CD) is an immune reaction as a consequence of ingestion of gluten. Diagnosis of CD is not easily using the clinical tests. Then, the discovery of appropriate methods for CD diagnosis is necessary. This study was concentrated to seek the metabolic biomarkers causes of CD compare to healthy subjects.In the present study, we classify CD and healthy subjects using classification and regression tree (CART). To find metabolites in serum which are helpful for the diagnosis of CD, the metabolic profiling was employed using the proton nuclear magnetic resonance spectroscopy (1HNMR). Based on CART results, it was concluded that just using one descriptor, CD and control groups could be classified separately. The 89 % of data in the test set was predicted correctly by the obtained classification model. Our study indicates that quantitative metabolite analysis of serum can be employed to distinguish healthy from CD subjects.
- Klíčová slova
- chemometrie, klasifikace a regresní stromy (CART), analýza metabolitů v séru,
- MeSH
- biologické markery MeSH
- celiakie * diagnóza klasifikace MeSH
- dospělí MeSH
- hodnotící studie jako téma MeSH
- interpretace statistických dat * MeSH
- klinické laboratorní techniky metody využití MeSH
- lidé středního věku MeSH
- lidé MeSH
- magnetická rezonanční spektroskopie diagnostické užití metody MeSH
- metabolomika * metody trendy MeSH
- sérologické testy MeSH
- výzkum MeSH
- zdraví dobrovolníci pro lékařské studie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
CART (cocaine- and amphetamine-regulated transcript) peptide is a neuropeptide with a powerful central anorexigenic effect. Specific CART peptide binding sites, most likely CART peptide receptors, have been found in PC12 cells. This study further characterizes the CART peptide binding sites in PC12 cells. After differentiation to a neuronal phenotype with nerve growth factor, the number of CART peptide binding sites in PC12 cells tripled. Following dexamethasone treatment, which transforms PC12 cells into chromaffin-like cells, the number of CART peptide binding sites substantially decreased. CART peptide did not affect the differentiation or acetylcholinesterase activity of PC12 cells, indicating that CART peptide does not participate in differentiation or neuronal activity. CART peptide increased the phosphorylation of SAPK/JNK (stress-activated protein kinase/c-Jun-amino-terminal kinase) and subsequent c-Jun protein expression. These effects were reversed by SP600125, a specific JNK-kinase inhibitor. CART peptide did not significantly affect ERK (extracellular signal-regulated kinase), CREB (cAMP responsive element binding protein), or p38 phosphorylation and c-Fos protein expression. Central administration of CART peptide into mice also resulted in increased c-Jun positive cells in dorsomedial hypothalamic nucleus and nucleus of the solitary tract, areas involved in food intake regulation. Activation of c-Jun by CART peptide might indicate a possible role of CART peptide in managing stress conditions rather than a role in cell proliferation or differentiation as well as the more complex and/or specific regulation ways by transcription factors in some nuclei involved in food intake regulation. The characteristics of stress that CART peptide potentially mediates should be further studied.
- MeSH
- acetylcholinesterasa analýza MeSH
- buňky PC12 MeSH
- hypothalamus účinky léků metabolismus MeSH
- krysa rodu rattus MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- nucleus solitarius účinky léků metabolismus MeSH
- proteiny nervové tkáně metabolismus farmakologie MeSH
- receptory peptidů metabolismus MeSH
- signální transdukce fyziologie MeSH
- vazebná místa MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
CART (cocaine- and amphetamine-regulated transcript) peptides are neuropeptides abundant in the central nervous system and periphery found to be involved in the regulation of food intake behavior and other physiological processes. Recently, we reported specific binding of (125)I-CART(61-102) to the rat adrenal pheochromocytoma cell line PC12, both intact cells and cell membranes. In this study, several fragments of CART(61-102) corresponding to its structural loops were synthesized and tested for their potency in binding experiments using PC12 intact cells and cell membranes and in feeding test with fasted mice. From all shorter peptides tested, only CART(74-86) and CART(62-86) containing disulfide bridges kept partial binding potency of the original molecule with K(i) in 10(-5) and 10(-4)M range. However, these fragments were not able to inhibit food intake after their central administration up to a dose of 4 nmol/mouse. The results showed that a compact structure containing three disulfide bridges is necessary for preservation of full biological activity of CART peptides.
- MeSH
- buňky PC12 MeSH
- financování organizované MeSH
- krysa rodu rattus MeSH
- molekulární sekvence - údaje MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- peptidové fragmenty farmakologie MeSH
- proteiny nervové tkáně farmakologie chemie MeSH
- sekvence aminokyselin MeSH
- stravovací zvyklosti účinky léků MeSH
- vztahy mezi strukturou a aktivitou MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
CART (cocaine- and amphetamine-regulated transcript) peptides are involved in food intake regulation, stress, and other physiological functions. Although CART peptides have been known for over 25 years, their receptor(s) have not yet been characterized. In this short review, we will summarize our previous studies, where we reported specific binding of 125 I-CART(61-102) to PC12 rat pheochromocytoma cells. Competitive binding experiments performed with mono- and di-iodinated peptides and their isoforms with oxidized Met67 resulted in nanomolar binding affinity. Moreover, in our previous study, CART(61-102), as well as di-iodinated CART(61-102), have shown a strong anorexigenic effect in fasted lean mice after intracerebroventricular administration. In conclusion, from our previous studies, iodination of CART(61-102) resulted in mono- and di-iodinated analogs with or without oxidized Met67 . All analogs revealed a high affinity to binding sites at PC12 cells and preserved biological activity.
- MeSH
- anorektika chemie farmakokinetika terapeutické užití MeSH
- buňky PC12 MeSH
- krysa rodu rattus MeSH
- myši MeSH
- proteiny nervové tkáně chemie farmakokinetika terapeutické užití MeSH
- radiofarmaka chemie farmakokinetika terapeutické užití MeSH
- radioizotopy jodu chemie MeSH
- vazba proteinů MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
CART (cocaine- and amphetamine-regulated transcript) peptides have been studied for ten years. We report specific binding of 125I-CART(61-102) to the rat adrenal pheochromocytoma PC12 cell line, both intact cells and cell membranes. Saturation binding to intact plated cells resulted in Kd of 0.48+/-0.16 nM and Bmax of 2228+/-529 binding sites/cell. 125I-CART(61-102) was also bound to PC12 cells differentiated using nerve growth factor to the neuronal phenotype with non-specific binding below 20%, and Kd of 1.90+/-0.27 nM and Bmax of 11,194+/-261 binding sites/cell. In competitive binding experiments, CART(61-102), CART(55-102) and di-iodinated CART(61-102) were bound to PC12 cell membranes with Ki in low nM range; their affinity to intact non-differentiated and differentiated cells was in low 10(-8) M range. In order to prove that iodination did not eliminate the pharmacological properties of CART, we tested the biological activity of di-iodinated CART(61-102). It decreased food intake in in vivo feeding experiment on fasted mice in a dose of 1 microg/mouse to the same extent as CART(61-102) in a dose of 0.5 microg/mouse.
- MeSH
- biologické modely MeSH
- buněčná diferenciace účinky léků MeSH
- buněčná membrána metabolismus MeSH
- buňky PC12 MeSH
- časové faktory MeSH
- fenotyp MeSH
- feochromocytom MeSH
- financování organizované MeSH
- izotopy jodu metabolismus MeSH
- kinetika MeSH
- krysa rodu rattus MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- nádory nadledvin MeSH
- neurony metabolismus patologie MeSH
- neurotrofní faktory farmakologie MeSH
- peptidové fragmenty metabolismus MeSH
- přijímání potravy účinky léků MeSH
- proteiny nervové tkáně farmakologie metabolismus MeSH
- radioizotopy jodu metabolismus MeSH
- vazba proteinů MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
The CART (cocaine- and amphetamine-regulated transcript) peptide is an anorexigenic neuropeptide that acts in the hypothalamus. The receptor and the mechanism of action of this peptide are still unknown. In our previous study, we showed that the CART peptide binds specifically to PC12 rat pheochromocytoma cells in both the native and differentiated into neuronal phenotype. Two biologically active forms, CART(55-102) and CART(61-102), with equal biological activity, contain three disulfide bridges. To clarify the importance of each of these disulfide bridges in maintaining the biological activity of CART(61-102), an Ala scan at particular S-S bridges forming cysteines was performed, and analogs with only one or two disulfide bridges were synthesized. In this study, a stabilized CART(61-102) analog with norleucine instead of methionine at position 67 was also prepared and was found to bind to PC12 cells with an anorexigenic potency similar to that of CART(61-102). The binding study revealed that out of all analogs tested, [Ala(68,86)]CART(61-102), which contains two disulfide bridges (positions 74-94 and 88-101), preserved a high affinity to both native PC12 cells and those that had been differentiated into neurons. In food intake and behavioral tests with mice after intracerebroventricular administration, this analog showed strong and long-lasting anorexigenic potency. Therefore, the disulfide bridge between cysteines 68 and 86 in CART(61-102) can be omitted without a loss of biological activity, but the preservation of two other disulfide bridges and the full-length peptide are essential for biological activity.
- MeSH
- anorektika chemie farmakologie MeSH
- buňky PC12 MeSH
- cystin chemie MeSH
- kompetitivní vazba MeSH
- krysa rodu rattus MeSH
- lokomoce účinky léků MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- nocicepce účinky léků MeSH
- peptidové fragmenty chemie farmakologie MeSH
- přijímání potravy účinky léků MeSH
- proteiny nervové tkáně chemie farmakologie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
