Cocaine- and amphetamine-regulated transcript peptide (CARTp) is an anorexigenic neuropeptide whose receptor is undisclosed. Previously, we reported the specific binding of CART(61-102) to pheochromocytoma PC12 cells, where CART(61-102) affinity and the number of binding sites per cell corresponded to ligand-receptor binding. Recently, Yosten et al. designated orphan GPR160 as the CARTp receptor, because the GPR160 antibody abolished neuropathic pain and anorexigenic effects induced by CART(55-102) and exogenous CART(55-102) coimmunoprecipitated with GPR160 in KATOIII cells. As no direct evidence that CARTp is a ligand for GPR160 has been described, we decided to verify this hypothesis by testing CARTp affinity to the GPR160 receptor. We investigated the GPR160 expression in PC12 cells since it is cell line known to specifically bind CARTp. Moreover, we examined the specific CARTp binding in THP1 cells, with high endogenous GPR160 expression and GPR160-transfected cell lines U2OS and U-251 MG. In PC12 cells, the GPR160 antibody did not compete for specific binding with 125I-CART(61-102) or with 125I-CART(55-102), and GPR160 mRNA expression and GPR160 immunoreactivity were not detected. Moreover, THP1 cells did not show any 125I-CART(61-102) or 125I-CART(55-102) specific binding despite GPR160 detection by fluorescent immunocytochemistry (ICC). Finally, no 125I-CART(61-102) or 125I-CART(55-102) specific binding in the GPR160-transfected cell lines U2OS and U-251 MG, selected due to their negligible endogenous expression of GPR160, was detected, despite the detection of GPR160 by fluorescent ICC. Our binding studies clearly demonstrated that GPR160 cannot be a receptor for CARTp. Further studies are needed to identify true CARTp receptors.

• MeSH
• kokain * MeSH
• krysa rodu rattus MeSH
• ligandy MeSH
• proteiny nervové tkáně * genetika   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

• Publikační typ
• abstrakty MeSH

• Publikační typ
• abstrakt z konference 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 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

BACKGROUND: CART (cocaine- and amphetamine-regulated transcript) peptide and cholecystokinin (CCK) are neuromodulators involved in feeding behavior. This study is based on previously found synergistic effect of leptin and CCK on food intake and our hypothesis on a co-operation of the CART peptide and CCK in food intake regulation and Fos activation in their common targets, the nucleus tractus solitarii of the brainstem (NTS), the paraventricular nucleus (PVN), and the dorsomedial nucleus (DMH) of the hypothalamus. RESULTS: In fasted C57BL/6 mice, the anorexigenic effect of CART(61-102) in the doses of 0.1 or 0.5 microg/mouse was significantly enhanced by low doses of CCK-8 of 0.4 or 4 microg/kg, while 1 mg/kg dose of CCK-A receptor antagonist devazepide blocked the effect of CART(61-102) on food intake. After simultaneous administration of 0.1 microg/mouse CART(61-102) and of 4 microg/kg of CCK-8, the number of Fos-positive neurons in NTS, PVN, and DMH was significantly higher than after administration of each particular peptide. Besides, CART(61-102) and CCK-8 showed an additive effect on inhibition of the locomotor activity of mice in an open field test. CONCLUSION: The synergistic and long-lasting effect of the CART peptide and CCK on food intake and their additive effect on Fos immunoreactivity in their common targets suggest a co-operative action of CART peptide and CCK which could be related to synergistic effect of leptin on CCK satiety

• MeSH
• antagonisté hormonů farmakologie   MeSH
• benzodiazepinony farmakologie   MeSH
• devazepid farmakologie   MeSH
• fenylmočovinové sloučeniny farmakologie   MeSH
• financování organizované MeSH
• hubenost MeSH
• injekce intraperitoneální MeSH
• injekce intraventrikulární MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• neurony metabolismus   účinky léků   MeSH
• nucleus dorsomedialis hypothalami fyziologie   účinky léků   MeSH
• nucleus paraventricularis hypothalami fyziologie   účinky léků   MeSH
• nucleus solitarius fyziologie   účinky léků   MeSH
• pátrací chování fyziologie   účinky léků   MeSH
• peptidové fragmenty farmakologie   MeSH
• proteiny nervové tkáně farmakologie   MeSH
• protoonkogenní proteiny c-fos metabolismus   MeSH
• receptor cholecystokininu A antagonisté a inhibitory   MeSH
• receptor cholecystokininu B antagonisté a inhibitory   MeSH
• regulace chuti k jídlu fyziologie   účinky léků   MeSH
• sinkalid farmakologie   MeSH
• synergismus léků MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• myši MeSH
• zvířata 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

Monosodium glutamate (MSG) treatment of neonatal mice results in a selective damage to the arcuate nucleus (ARC) and development of obesity with increased adiposity at sustained body weight in the adulthood. Feeding pattern of the MSG obese mice is unusual. Our previous results showed that after 24-h fasting, MSG mice consumed negligible amount of food in several hours and therefore, it was impossible to register the effect of peptides attenuating food intake such as cholecystokinin (CCK) or cocaine- and amphetamine-regulated transcript (CART) peptide. To overcome this problem, two findings were used: firstly, orexigenic effect of neuropeptide Y (NPY) was attenuated both by CCK or CART peptide in lean fed mice and secondly, orexigenic effect of NPY was preserved in fed rats with MSG obesity. In this study, short-term food intake in fed lean and MSG obese C57BL/6 male mice was measured after simultaneous central administration of orexigenic NPY with either CART peptide or peripherally administered CCK. Anorexigenic action of exogenous CART peptide was preserved in MSG obese mice. On the other hand, satiety effect of exogenous CCK was completely lost in MSG obese mice. In conclusion, effective leptin signaling in ARC is necessary for satiety effect of CCK.

• MeSH
• cholecystokinin fyziologie   MeSH
• financování organizované MeSH
• glutamát sodný MeSH
• modely nemocí na zvířatech MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• neuropeptid Y fyziologie   MeSH
• nucleus arcuatus hypothalami fyziologie   MeSH
• obezita chemicky indukované   patofyziologie   MeSH
• proteiny nervové tkáně fyziologie   MeSH
• regulace chuti k jídlu MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH

AIMS: This study investigates the neuroprotective effects of lipidized analogues of 2-SS-CART(61-102) derived from anorexigenic neuropeptide cocaine- and amphetamine-regulated transcript peptide (CARTp) in light of the link between obesity, its comorbidities, and the development of Alzheimer's disease. METHODS: We introduce novel lipidized analogues derived from 2-SS-CART(61-102), a specific analogue of natural CART(61-102), with two disulfide bridges. Using hypothermic PC12 cells, we tested the effect of the most potent analogues on Tau phosphorylation. We further described the anorexigenic and neuroprotective potential of subcutaneously (SC) injected lipidized CARTp analogue in a mouse model with prediabetes and obesity induced by neonatal monosodium glutamate (MSG) administration. RESULTS: Compared to the non-lipidized 2-SS-CART(61-102), all lipidized analogues exhibited a potent binding affinity to PC12 cells and enhanced in vitro stability in rat plasma. Two most potent lipidized analogues attenuated hypothermia-induced Tau hyperphosphorylation at multiple epitopes. Subsequently, chronic SC treatment with palm-2-SS-CART(61-102) significantly decreased body weight and food intake, improved metabolic parameters, decreased level of pTau and increased neurogenesis in hippocampi of obese MSG mice. CONCLUSION: Our unique CARTp analogue palm-2-SS-CART(61-102) shows promise as a potent anti-obesity and neuroprotective agent.

• MeSH
• anorektika farmakologie   MeSH
• buňky PC12 MeSH
• fosforylace účinky léků   MeSH
• glutamát sodný * MeSH
• krysa rodu rattus MeSH
• lipidy chemie   krev   MeSH
• modely nemocí na zvířatech MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• neuroprotektivní látky * farmakologie   MeSH
• obezita * metabolismus   farmakoterapie   MeSH
• proteiny nervové tkáně * metabolismus   MeSH
• proteiny tau metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

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