Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "opioid peptides" wg kryterium: Temat


Wyświetlanie 1-9 z 9
Tytuł:
Cyclic dermorphin tetrapeptide analogues obtained via ring-closing metathesis
Autorzy:
Berezowska, Irena
Chung, Nga
Lemieux, Carole
Wilkes, Brian
Schiller, Peter
Powiązania:
https://bibliotekanauki.pl/articles/1041269.pdf
Data publikacji:
2006
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
opioid activity profile in vitro
cyclic dermorphin analogues
opioid peptides
ring-closing metathesis
dermorphin
Opis:
The dermorphin-derived cyclic tetrapeptide analogues H-Tyr-c[d-Cys-Phe-Cys]NH2 and H-Tyr-c[d-Cys-Phe-D-Cys]NH2 are opioid agonists at the µ and δ receptor. To enhance the metabolic stability of these peptides, we replaced the disulfide bridge with a bis-methylene moiety. This was achieved by solid-phase synthesis of the linear precursor peptide containing allylglycine residues in place of the Cys residues, followed by ring-closing metathesis. In the case of the peptide with L-configuration in the 4-position both the cis and the trans isomer of the resulting olefinic peptides were formed, whereas the cis isomer only was obtained with the peptide having the d-configuration in position 4. Catalytic hydrogenation yielded the saturated -CH2-CH2- bridged peptides. In comparison with the cystine-containing parent peptides, all olefinic peptides showed significantly reduced µ and δ agonist potencies in the guinea pig ileum and mouse vas deferens assays. The -CH2-CH2-bridged peptide with l-configuration in the 4-position was equipotent with its cystine-containing parent in both assays, whereas the bis-methylene analogue with d-configuration in position 4 was 10-27-fold less potent compared to its parent. The effect of the disulfide replacements with the -CH=CH- and-CH2-CH2- moieties on the conformational behavior of these peptides was examined by theoretical conformational analysis which provided plausible explanations in terms of structural parameters for the observed changes in opioid activity.
Źródło:
Acta Biochimica Polonica; 2006, 53, 1; 73-76
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
DALDA analogues containing α-hydroxymethylamino acids.
Autorzy:
Olma, Aleksandra
Chung, Nga
Schiller, Peter
Zabrocki, Janusz
Powiązania:
https://bibliotekanauki.pl/articles/1044058.pdf
Data publikacji:
2001
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
amphiphilic amino acids
α-hydroxymethylamino acids
DALDA analogues
opioid activity in vitro
opioid peptides
Opis:
To evaluate the role of aromatic amino-acids residues, four analogues of the μ-selec-tive opioid peptide agonist DALDA (H-Tyr-D-Arg-Phe-Lys-NH2) containing the amphiphilic, α,α-disubstituted amino acid (R)- or (S)-α-hydroxymethyltyrosine (HmTyr) in position 1 and (R)- or (S)-α-hydroxymethylphenylalanine (HmPhe) in position 3 of the peptide sequence were synthesized. Only the [(R)-HmPhe3)]DALDA analogue displayed full agonistic activity in both the guinea pig ileum and the mouse vas deferens assays and turned out to be a δ receptor-selective opioid agonist.
Źródło:
Acta Biochimica Polonica; 2001, 48, 4; 1121-1124
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dansylated analogues of the opioid peptide [Dmt1]DALDA: in vitro activity profiles and fluorescence parameters.
Autorzy:
Berezowska, Irena
Lemieux, Carole
Chung, Nga
Zelent, Bogumil
Schiller, Peter
Powiązania:
https://bibliotekanauki.pl/articles/1043324.pdf
Data publikacji:
2004
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
fluorescence spectroscopy
opioid activity profile in vitro
fluorescence quantum yield
opioid peptides
fluorescent opioid peptide analogues
[Dmt1]DALDA
Opis:
Dansylated analogues of the potent and selective μ opioid peptide agonist [Dmt1]DALDA (H-Dmt-D-Arg-Phe-Lys-NH2; Dmt = 2',6'-dimethyltyrosine) were prepared either by substitution of Nβ-dansyl-α,β-diaminopropionic acid or Nε-dansyllysine for Lys4, or by attachment of a dansyl group to the C-terminal carboxamide function via a linker. All three analogues displayed high μ agonist potency in vitro and the C-terminally dansylated one retained significant μ receptor selectivity. The three analogues showed interesting differences in their fluorescence emission maxima and quantum yields, indicating that the dansyl group in two of them was engaged in intramolecular hydrophobic interactions. These dansylated [Dmt1]DALDA analogues represent valuable tools for binding studies, cellular uptake and intracellular distribution studies, and tissue distribution studies.
Źródło:
Acta Biochimica Polonica; 2004, 51, 1; 107-113
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis and binding properties of deltorphin I analogues containing (R) and (S)-α-hydroxymethylnaphtylalanine.
Autorzy:
Olma, Aleksandra
Gniadzik, Agnieszka
Lipkowski, Andrzej
Łachwa, Magdalena
Powiązania:
https://bibliotekanauki.pl/articles/1044072.pdf
Data publikacji:
2001
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
deltorphin I analogues
amphiphilic amino acids
α,α-disubstituted amino acids
opioid peptides
opioid receptor binding
α-hydroksymethylamino acids
Opis:
New analogues of deltorphin I (DT I), in which the phenylalanine residue in position 3 is substituted with amphiphilic α,α-disubstituted amino acid enantiomers, (R) and (S)-α-hydroxymethylnaphtylalanine, were synthesized and tested for μ and δ opioid receptor affinity and selectivity. Although both analogues have lower affinity to δ receptors than DT I, they both expressed specificity to δreceptors.
Źródło:
Acta Biochimica Polonica; 2001, 48, 4; 1165-1168
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Potencjalne zastosowanie enkefalin w diagnostyce i terapii różnych chorób
Potential application enkephalns in diagnostics and treatment of various diseases
Autorzy:
Sobocińska, M.
Kamysz, E.
Powiązania:
https://bibliotekanauki.pl/articles/172068.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
endogenne peptydy opioidowe
enkefaliny
Leu-enkefalina
Met-enkefalina
endogenous opioid peptides
enkephalins
Met-enkephalin
Leu-enkephalin
Opis:
For the past few years enkephalins have been a center of appreciation and interest. Enkephalins were discovered in 1975 by Hughes, Kosterlitz and coworkers [1]. They can be described as short sequences of amino acids that are naturally produced in the central nervous system (CNS) in various glands throughout the body, such as the pituitary and adrenal glands [7, 9]. There were revealed two forms of enkephalins, one containing leucine, and the other containing methionine. Enkephalins are produced by the cleavage of a precursor protein called proenkephalin. From proenkephalin originate Met- and Leu-enkephalin, Met-enkephalin-Arg6-Gly7- -Leu8, Met-enkephalin-Arg6-Phe7 [1–3]. Enkephalins are involved in phenomena associated with modulated pain perception [13], regulation of memory and emotional conditions [21] and regulation of immunological system [29]. They also have an impact on the cardiovascular system [17], motility of the digestive system and metabolism of carbohydrates [8]. This article is a review of the current knowledge about enkephalins and their usage in the diagnostics and treatment of a variety of diseases: diseases/disorders of the central nervous system [21, 22], Parkinson’s disease [27], disease of the immune system [29], chronic pain [12], tumor diseases/cancer [33], heart and cardiovascular diseases [19] and inflammatory bowel disease [23].
Źródło:
Wiadomości Chemiczne; 2017, 71, 1-2; 33-44
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cyclic enkephalin-deltorphin hybrids containing a carbonyl bridge: structure and opioid activity
Autorzy:
Ciszewska, Małgorzata
Ruszczyńska, Katarzyna
Oleszczuk, Marta
Chung, Nga
Witkowska, Ewa
Schiller, Peter
Wójcik, Jacek
Izdebski, Jan
Powiązania:
https://bibliotekanauki.pl/articles/1039922.pdf
Data publikacji:
2011
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
cyclic opioid peptides
conformation
NMR
N-(ureidoethyl)amides
side-chain to side-chain cyclization
structure-activity relationship
Opis:
Six hybrid N-ureidoethylamides of octapeptides in which an N-terminal cyclic structure related to enkephalin was elongated by a C-terminal fragment of deltorphin were synthesized on MBHA resin. The synthetic procedure involved deprotection of Boc groups with HCl/dioxane and cleavage of the peptide resin with 45 % TFA in DCM. d-Lys and d-Orn were incorporated in position 2, and Lys, Orn, Dab, or Dap in position 5. The side chains of the dibasic amino function were protected with the Fmoc group. This protection was removed by treatment with 55 % piperidine in DMF, and cyclization was achieved by treatment with bis-(4-nitrophenyl)carbonate. Using various combinations of dibasic amino acids, peptides containing a 17-, 18-, 19- or 20-membered ring structure were obtained. The peptides were tested in the guinea-pig ileum (GPI) and mouse vas deferens (MVD) assays. Diverse opioid activities were observed, depending on the size of the ring. Extension of the enkephalin sequence at the C-terminus by a deltorphin fragment resulted in a change of receptor selectivity in favor of the δ receptor. The conformational propensities of selected peptides were determined using the EDMC method in conjunction with data derived from NMR experiments carried out in water. This approach allowed proper examination of the dynamical behavior of these small peptides. The results were compared with those obtained earlier with corresponding N-(ureidoethyl)pentapeptide amides.
Źródło:
Acta Biochimica Polonica; 2011, 58, 2; 225-230
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Biwalentne ligandy receptorów opioidowych
Bivalent ligands of opioid receptors
Autorzy:
Frączak, O.
Olma, A.
Powiązania:
https://bibliotekanauki.pl/articles/171626.pdf
Data publikacji:
2014
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
peptydy opioidowe
biwalentne ligandy niepeptydowe
biwalentne ligandy peptydowe
aktywność opioidowa
homobiwalentne ligandy
heterobiwalentne ligandy
opioid peptides
nonpeptide bivalent ligands
peptide bivalent ligands
opioid activity
homobivalent ligands
heterobivalent ligands
Opis:
Opioids are the oldest drugs know to humanity, which have been and continue to be used for the treatment of chronic pain. Unfortunately they have a large numbers of side effects [1–6]. Three main types of opioid receptors μ (MOR), δ (DOR) and κ (KOR) are known [8]. The ORL1 receptor was classified as the fourth member of opioid receptor family [9]. Opioid receptors can form homodimers and the following heterodimers: DOR-KOR, DOR-MOR and KOR-MOR [13c,d,f, 14]. Specially designed ligands which are able to penetrate the BBB are used to study physiological consequences of opioid receptor homo- and heterodimerization, and as new analgesics. Bivalent ligands are defined as compounds that contain two pharmacophoric units, an appropriately designed spacer to separate and define the two pharmacophores, and a linker unit to connect the pharmacophores, to the spacer (Fig. 1) [16]. The affinity of a ligand to its target depends on its fundamental kinetic association and dissociation rate constants (Scheme 1) [24]. Bivalent ligands interacting with the opioid receptors have been divided into three groups: nonpeptide, peptide- nonpeptide and peptide homo- or heterodimers. Nonpeptide bivalent ligands (4–21, 27–41 and 44–45) containing different pharmacophores (selective opioid agonists or/and antagonists) connected with designed linkers have potent analgesic properties [25–34]. Compound 35 may be useful in the treatment of opioid dependence. Studies of peptide-nonpeptide ligands, which are a combination of “address” segments of endogenous opioid peptides and selective alkaloid ligand (47–50) indicate that peptide part of the analogues can modulate the receptor selectivity of the attached alkaloid pharmacophores [35]. Series of peptide-nonpeptide ligands containing different classes of opioid peptides and fentanyl (52–86) were synthesized and tested for binding affinity to μ and δ opioid receptors [38–40]. Good opioid affinity and antinociceptive activity of some of the obtained bivalent ligands (57, 61, 63) suggesting that a novel class of analgesics can be further developed utilizing this approach. Among homobivalent ligands the most important is biphalin 87 and its analogues (88–124) [41–53]. Analgesic potency of the most active ligand 112 is greater than parent peptide (biphalin) and morphine.
Źródło:
Wiadomości Chemiczne; 2014, 68, 3-4; 233-255
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Badanie struktury i dynamiki N-terminalnych sekwencji dermorfiny i ich analogów z wykorzystaniem spektroskopii NMR w ciele stałym i rentgenografii
Studies on the structure and dynamics of N-terminal sequences of dermorphin and their analogs by means of solid state NMR spectroscopy and XRD
Autorzy:
Trzeciak-Karlikowska, K.
Powiązania:
https://bibliotekanauki.pl/articles/171648.pdf
Data publikacji:
2012
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
peptydy opioidowe
oddziaływania CH-pi
dynamika molekularna
oddziaływanie peptyd–fosfolipid
spektroskopia NMR
1H Ultra Fast MAS NMR
PISEMA MAS
PILGRIM
XRD
opioid peptides
CH-pi interactions
molecular dynamics
peptide–phospholipid interaction
NMR spectroscopy
Opis:
Deltorphin I (Tyr-d-Ala-Phe-Asp-Val-Val-Gly-NH_2) and dermorphin (Tyr-d-Ala-Phe- -Gly-Tyr-Pro-Ser-NH_2) are natural opioid peptides that have been isolated from the skin of South American frogs [1]. The presence of d-amino acid is crucial for their biological activity. The synthetic analogs of given heptapeptides containing l-alanine are not analgesics [2]. Analysis of the influence of stereochemistry on molecular packing, dynamics and biological functions of neuropeptides is still important for receptor studies and practical applications (e.g. design of new selective pain killers). Presented research is focused on the structure and dynamics of two N-terminal sequences of dermorphin: tripeptide Tyr-d-Ala-Phe 1, tetrapeptide Tyr-D-Ala-Phe-Gly 2, and their analogs with l-alanine: Tyr-Ala-Phe 3 and Tyr-Ala-Phe-Gly 4, using solid state NMR and X-ray diffraction. This study clearly demonstrates that 1 and 2 crystallized under different conditions to form exclusively one structure [3, 4]. In contrast, tripeptide and tetrapeptide with l-Ala in the sequence very easily form different crystal modifications. Tyr-Ala-Phe 3 crystallizes into two forms: 3a and 3b [5], while Tyr-Ala-Phe-Gly 4 gives three modifications: 4a, 4b and 4c [4]. It seems that one of the factors, which can be important in the preorganization mechanism anticipating the formation of crystals, is the intramolecular CH-đ interaction between aromatic rings of tyrosine and/or phenylalanine and the methyl group of alanine. Such interaction is possible only for d-Ala residue. For l-Ala in the peptide sequence, the methyl group is aligned on the opposite side with respect at least to one of the aromatic groups. It can be further speculated that such internal CH-π contacts can also occur during the interaction of ligand–receptor, making the message sequence of opioid peptides more rigid and finally selective. By employing different NMR experiments (e.g. PISEMA MAS and PILGRIM) it was proven that the main skeleton of analyzed peptides is rigid, whereas significant differences in the molecular motion of the aromatic residues were observed [4, 6]. Solid state 2H NMR spectroscopy of samples with deuterium labeled aromatic rings: Tyrd4-d-Ala-Phe 5, Tyr-d-Ala-Phed5 6, Tyrd4-Ala-Phe 7, Tyr-Ala-Phe^d5 8 was used to analyze the geometry and time scale of the molecular motion. At ambient temperature, the tyrosine ring of sample 5 is rigid and in the sample 6 the phenylalanine ring undergoes a "π -flip". The tyrosine rings of form I of 7 and 8 are static, while the phenylalanine rings of form II of 7 and 8 undergo a fast regime exchange [6]. Variable temperature 2H measurements proved that the tyrosine and phenylalanine rings of two forms of compounds 7 and 8 became more mobile with increasing temperature. In contrast, the aromatic rings of samples 5 and 6 preserve their dynamics regime (static tyrosine and "π -flip" phenylalanine) in a large range of temperatures [6]. The analysis of 13C, 15N labeled tetrapeptide Tyr-D-Ala-Phe-Gly 2’-phospholipid membrane interactions suggests that peptide 2’ is aligned on the surface of the membrane (RFDR MAS) and the sandwich-like π -CH_3-π arrangement of the pharmacophore is preserved (DARR) [7].
Źródło:
Wiadomości Chemiczne; 2012, 66, 9-10; 867-891
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Charakterystyka endogennych inhibitorów enzymów rozkładających enkefaliny
Characteristic of the endogenous enkephalin degrading enzymes inhibitors
Autorzy:
Sobocińska, M.
Maćkiewicz, Z.
Powiązania:
https://bibliotekanauki.pl/articles/171530.pdf
Data publikacji:
2014
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
inhibitory
inhibitory enzymów rozkładających enkefaliny
Els
endogenne inhibitory enzymów rozkładających enkefaliny
opiody
peptydy
ból
środki przeciwbólowe
inhibitors
endogenous enkephalin degrading enzymes inhibitors
opioid
peptides
pain
analgesicagents
Opis:
Management of acute and chronic pain has always been a key area of clinical research. Pain and stress stimulation may cause an increase in the level of endogenous opioids in the body. Endogenous enkephalins activate opioid receptors in the brain, leading to the analgesic effect. Enkephalinases inactivate endogenous opioids, abolishing their activity. Enkephalin degrading enzyme inhibitors (EIs) in turn inhibit these enzymes, preventing them from degrading endogenous enkephalins what leads to analgesia. The enkephalin degrading enzyme inhibitors seem to be promising analgesic agents [2]. Analgesic effect of EIs has been discovered recently and their therapeutic potential has not been effectively investigated yet. The main advantage of enkephalinase inhibitors is that they do not show adverse effects characteristic for opioids. EIs play an important role in modulating nociception, so they are potential agents for the treatment of acute and chronic pain. They often possess also additional antidiarrheal, antidepressant and anticancer properties [3]. The potential EIs targets appear to be aminopeptidase N (APN), dipeptidyl peptidase III (DPP III), angiotensin-converting enzyme (ACE) and neutral endopeptidase (NEP) [4]. EIs may be broadly classified as endogenous and those that are obtained synthetically [4]. The purpose of this work is to present a review of endogenous enkephalinase inhibitors: sialorphin, opiorphin, and spinorphin. Sialorphin (Gln-His-Asn-Pro-Arg) is synthesized predominantly in the submandibular gland and prostate of adult rats in response to androgen steroids and is released locally and systemically in response to stress. Sialorphin protects endogenous enkephalins released after nociceptive stimuli by inhibiting NEP in vivo. Sialorphin prevents spinal and renal NEP from breaking down substance P and Met-enkephalin in vitro. Sialorphin suppressed pain sensation for both chemical- -induced inflammation and acute physical pain [8, 9, 12]. Opiorphin (Gln-Arg-Phe-Ser-Arg) is an endogenous chemical compound first isolated from human saliva. Opiorphin is a natural analgesic. Opiorphin protects enkephalins from degradation by human neutral endopeptidase and aminopeptidase N. Opiorphin is closely related to the rat sialorphin peptide [12, 13, 19]. Spinorphin (Leu-Val-Val-Tyr-Pro-Trp-Thr) has been isolated from the bovine spinal cord as an endogenous inhibitor of enkephalin - degrading enzymes. Spinorphin is an antagonist of the P2X3 receptor and a weak partial agonist/antagonist of the FP1 receptor [24, 25, 26].
Źródło:
Wiadomości Chemiczne; 2014, 68, 3-4; 317-327
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-9 z 9

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies