• Journal of Integrative Natural Science
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• v.5 no.2
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• pp.65-71
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• 2012

Neuropeptide Y (NPY), a 36-amino acid polypeptide, is a member of the pancreatic polypeptide family, which consists of NPY, peptide YY (PYY) and pancreatic polypeptide (PP). The neuropeptide Y (NPY) receptors called Y receptors belongs to G-protein coupled that are involved in a variety of physiological functions such as appetite regulation, circadian rhythm and anxiety. Five receptor subtypes have been cloned in mammals (Y1, Y2, Y4, Y5, and Y6) of which four are functional. In this short review, information about the functional NYP receptors was analyzed. Sequence analyses were done between these receptors to identify the relationships between them. Phylogram was generated between these receptors to identify the close homologue between these receptors. Our sequence analyses found that Y1 and Y4 receptors are close than the other receptors. Further structure based analysis could be useful to identify subtype selective antagonists and dual antagonists targeting Y1 and Y4 receptors.

• Biomolecules & Therapeutics
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• v.25 no.1
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• pp.57-68
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• 2017

Seven transmembrane receptors (7TMRs), also known as G protein-coupled receptors, are popular targets of drug development, particularly 7TMR systems that are activated by peptide ligands. Although many pharmaceutical drugs have been discovered via conventional bulk analysis techniques the increasing availability of structural and evolutionary data are facilitating change to rational, targeted drug design. This article discusses the appeal of neuropeptide-7TMR systems as drug targets and provides an overview of concepts in the evolution of vertebrate genomes and gene families. Subsequently, methods that use evolutionary concepts and comparative analysis techniques to aid in gene discovery, gene function identification, and novel drug design are provided along with case study examples.

• Clinical and Experimental Reproductive Medicine
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• v.39 no.2
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• pp.87-93
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• 2012

Objective: Lin28 has been known to control the proliferation and pluripotency of embryonic stem cells. The purpose of this study was to determine the downstream effectors of Lin28 in mouse embryonic stem cells (mESCs) by RNA interference and microarray analysis. Methods: The control siRNA and Lin28 siRNA (Dharmacon) were transfected into mESCs. Total RNA was prepared from each type of transfected mESC and subjected to reverse transcription-polymerase chain reaction (RT-PCR) analysis to confirm the downregulation of Lin28. The RNAs were labeled and hybridized with an Affymetrix Gene-Chip Mouse Genome 430 2.0 array. The data analysis was accomplished by GenPlex 3.0 software. The expression levels of selected genes were confirmed by quantitative real-time RT-PCR. Results: According to the statistical analysis of the cDNA microarray, a total of 500 genes were altered in Lin28-downregulated mESCs (up-regulated, 384; down-regulated, 116). After differentially expressed gene filtering, 31 genes were selected as candidate genes regulated by Lin28 downregulation. Among them, neuropeptide Y5 receptor and oocyte-specific homeobox 5 genes were significantly upregulated in Lin28-downregulated mESCs. We also showed that the families of neuropeptide Y receptor (Npyr) and oocyte-specific homeobox (Obox) genes were upregulated by downregulation of Lin28. Conclusion: Based on the results of this study, we suggest that Lin28 controls the characteristics of mESCs through the regulation of effectors such as the Npyr and Obox families.

• Journal of Integrative Natural Science
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• v.5 no.3
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• pp.168-174
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• 2012

Gal (1-3) receptors are members of GPCR superfamily with seven transmembrane helices. The neuropeptide galanin mediates its effects through the receptor subtypes Gal1, Gal2, and Gal3 and has been implicated in anxiety and depression related behaviors. Galanin receptors are considered to be important targets for the development of novel antidepressant drugs. Owing to the importance of these receptors, a short communication about the sequential and structural studies about the functional Galanin (1-3) receptors has been reported. Structural studies have been hampered due to the lack of X-ray crystal structures. However with the availability of templates with close homologs comparative modeling could be encouraging. Sequence analysis was done for each receptors and homology modeling of each receptors were done with recently reported templates. Comparative analyses were done between these receptors to identify the relationships between them sequentially. Phylogram was generated between these receptors to identify the close homologue between this receptor and found that Gal2 and Gal3 receptors are closer. Our results could be useful for further structure based drug design targeting Gal1, Gal2 and Gal3 receptors.

• The Korean Journal of Physiology and Pharmacology
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• v.5 no.6
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• pp.479-485
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• 2001

The existence of opioid receptors in mammalian cerebellum except human, has not been clearly understood. In the present study, we found that NPY was inducible by morphine in the mouse cerebellar granular and Purkinje cell layers. We performed in situ RT-PCR and immunohistochemistry to characterize the NPY expression. The increase of NPY gene expression by morphine (30 mg/kg, i.p.) was inhibited by pretreatment with not only naloxone (100 mg/kg, i.p.) but also a noncompetitive NMDA antagonist, MK-801 (0.3 mg/kg, i.p.). The competitive NMDA antagonist, AP-5 (0.9 mg/kg, i.p.) slightly attenuated the increased NPY expression by morphine. Also, the finding similar to morphine was shown by NMDA (70 mg/kg, i.p.) treatment. Our results indicate that NPY was inducible by morphine and this might reflect activation of NMDA receptors in granule cells that relay mossy fiber inputs to Purkinje cells via parallel fibers.

• Genomics & Informatics
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• v.14 no.1
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• pp.12-19
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• 2016

Neuropeptides produced from prohormones by selective action of endopeptidases are vital signaling molecules, playing a critical role in a variety of physiological processes, such as addiction, depression, pain, and circadian rhythms. Neuropeptides bind to post-synaptic receptors and elicit cellular effects like classical neurotransmitters. While each neuropeptide could have its own biological function, mass spectrometry (MS) allows for the identification of the precise molecular forms of each peptide without a priori knowledge of the peptide identity and for the quantitation of neuropeptides in different conditions of the samples. MS-based neuropeptidomics approaches have been applied to various animal models and conditions to characterize and quantify novel neuropeptides, as well as known neuropeptides, advancing our understanding of nervous system function over the past decade. Here, we will present an overview of neuropeptides and MS-based neuropeptidomic strategies for the identification and quantitation of neuropeptides.

• The Korean Journal of Physiology and Pharmacology
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• v.12 no.5
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• pp.217-223
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• 2008

To directly test if elevated glucocorticoids are required for fasting-induced regulation of growth hormone (GH)-releasing hormone (GHRH), GHRH receptors (GHRH-R) and ghrelin receptors (GHS-R) expression, male rats were bilaterally adrenalectomized or sham operated. After 7 days, animals were fed ad libitum or fasted for 48 h. Bilateral adrenalectomy increased hypothalamic GHRH to 146% and decreased neuropeptide Y (NPY) mRNA to 54% of SHAM controls. Pituitary GHRH-R and GHS-R mRNA levels were decreased by adrenalectomy to 30% and 80% of shamoperated controls. In shamoperated rats, fasting suppressed hypothalamic GHRH (49%) and stimulated NPY (166%) mRNA levels, while fasting increased pituitary GHRH-R (391%) and GHS-R (218%) mRNA levels. However, in adrenalectomized rats, fasting failed to alter pituitary GHRH-R mRNA levels, while the fasting-induced suppression of GHRH and elevation of NPY and GHS-R mRNA levels remained intact. In fasted adrenalectomized rats, corticosterone replacement increased GHRH-R mRNA levels and intensified the fasting-induced decrease in GHRH, but did not alter NPY or GHS-R response. These data suggest that elevated glucocorticoids mediate the effects of fasting on hypothalamic GHRH and pituitary GHRH-R expression, while glucocorticoids are likely not the major determinant in fasting-induced increases in hypothalamic NPY and pituitary GHS-R expression.

• Biomolecules & Therapeutics
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• v.18 no.2
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• pp.152-158
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• 2010

Melanin concentrating hormone is a neuropeptide highly expressed in the brain that regulates several physiological functions mediated by receptors in the G-protein coupled receptor family, especially plays an important role in the complex regulation of energy balance and body weight mediated by the melanin concentrating hormone receptor subtype 1 (MCH1). Compelling pharmacological evidence implicating MCH1 signaling in the regulation of food intake and energy expenditure has generated a great deal of interest by pharmaceutical companies as MCH1 antagonists may have potential therapeutic benefit in the treatment of obesity and metabolic syndrome. Although fluorescence-based calcium mobilization assay platform has been one of the most widely accepted tools for receptor research and drug discovery, fluorescence interference and shallow assay window limit their application in high throughput screening and have led to a growing interest in alternative, luminescence-based technologies. Herein, a luminescence-based functional assay system for the MCH1 receptor was developed and validated with the mitochondrial targeted aequorin. Aequorin based functional assay system for MCH1 presented excellent Z' factor (0.8983) and high signal-to-noise ratio (141.9). The nonpeptide MCH1 receptor antagonist, SNAP 7941 and GSK 803430, exhibited $IC_{50}$ values of 0.62 ${\pm}$ 0.11 and 12.29 ${\pm}$ 2.31 nM with excellent correlation coefficient. These results suggest that the aequorin based assay system for MCH1 is a strong alternative to the traditional GPCR related tools such as radioligand binding experiments and fluorescence functional determinations for the compound screening and receptor research.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.8
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• pp.5336-5342
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• 2015

Although demand for scar treatment has been rising as our quality of life is improved, most scar treatment products rely on importation. Enkephalin is one of the neuropeptides secreted from neuronal ends. As both skin and neuron are derived from the exoderm during the development process, skin cells express opioid receptors as neuronal cells do. Opioid receptors are categorized into three types, mu(m)-, delta(d)-, and kappa(k)- opioid receptors, all of which are directly involved in the wound healing process. In this study, enkephalin derivatives are synthesized by Alanin Scan and their efficacy was evaluated and compared. In vitro wound healing effects, stimulatory effects of collagen synthesis, and skin hydration effects were also evaluated and confirmed. Among Enkephalin derivatives, AS13 showed highest wound healing effect.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.9
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• pp.1294-1299
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• 2016

An experiment was conducted to investigate the effect of peripheral insulin treatment on appetite in chicks. Six-d-age chicks with ad libitum feeding or fasting for 3 h before injection received a subcutaneous injection of 0, 1, 3, 5, 10, or 20 IU of insulin or vehicle (saline). The results showed peripheral insulin treatment (1 to 20 IU) did not alter significantly the feed intake in chicks under either ad libitum feeding or fasting conditions within 4 h (p>0.05). Compared with the control, plasma glucose concentration was significantly decreased after insulin treatment of 3, 5, 10, and 20 IU for 4 h in chicks with ad libitum feeding (p<0.05). In fasted chicks, 10 and 20 IU insulin treatments significantly decreased the plasma glucose level for 4 h (p<0.05). Peripheral insulin treatment of 10 IU for 2 or 4 h did not significantly affect the hypothalamic genes expression of neuropeptide Y, proopiomelanocortin, corticotropin-releasing factor and insulin receptors (p>0.05). All results suggest peripheral administration of insulin has no effect on appetite in chicks.