MOG (35-55)
(Synonyms: 髓鞘少突胶质细胞糖蛋白,endrocyte Glycoprotein Peptide (35-55)) 目录号 : GC17193
MOG (35-55) is a 35-55 fragment of myelin oligodendrocyte glycoprotein.
Cas No.:149635-73-4
Sample solution is provided at 25 µL, 10mM.
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Quality Control & SDS
- View current batch:
- Purity: >98.00%
- COA (Certificate Of Analysis)
- SDS (Safety Data Sheet)
- Datasheet
| Cell experiment [1]: | |
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Cell lines |
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Preparation Method |
To prepare T cell lines specific for MOG (35-55) peptide, C57BL/6 mice were immunized s.c. in the flanks with 0.2 ml of an emulsion containing 200 µg of MOG (35-55) in saline and an equal volume of CFA containing 400 µg Mycobacterium tuberculosis H37RA. Ten days after immunization, lymph node cells were cultured with MOG (35-55) (20 µg/ml) at 8 × 106 cells/ml in stimulation medium (RPMI 1640 medium supplemented with nonessential amino acids, sodium pyruvate, 2-ME, and 10% FBS) for 48 h. The T cells were expanded in medium containing IL-2 (100 U/ml). |
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Reaction Conditions |
20 µg/ml, 5-10 days |
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Applications |
After 5-10 days in culture, the T cell lines responded specifically to MOG (35-55) peptide. |
| Animal experiment [2]: | |
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Animal models |
6-8 weeks old female C57BL/6 mice |
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Preparation Method |
Mice were immunized subcutaneously at the base of the tail with 100 µl of mouse MOG (35-55) peptide emulsified in complete Freund's adjuvant (CFA). Peptide was dissolved in phosphate-buffered saline (PBS) at 2 mg/ml, mixed at a 1:1 ratio with complete adjuvant (8 mg/ml heat-killed Mycobacterium tuberculosis (H37 RA) in incomplete Freund's adjuvant (IFA)), and emulsified by the syringe-extrusion method with two rubber-free Luer-Lock syringes (Air-Tite) connected by a 3-way stopcock until a stable emulsion was formed (approx. 10 min). Each mouse received 100 µg of peptide (and 400 µg of M. tuberculosis). On the day of immunization and two days later, 250 ng of pertussis toxin in 100 µl PBS was administered intravenously. |
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Dosage form |
Subcutaneous injection, 100 µg in 100 µl |
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Applications |
Immunization of C57BL/6 mice with MOG (35-55) caused inflammation and axon loss in the spinal cord but resulted in only minimal demyelination |
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References: [1]: Ito A, Matejuk A, Hopke C, et al. Transfer of severe experimental autoimmune encephalomyelitis by IL-12-and IL-18-potentiated T cells is estrogen sensitive[J]. The Journal of Immunology, 2003, 170(9): 4802-4809. | |
MOG (35-55) is a 35-55 fragment of myelin oligodendrocyte glycoprotein [1]. Immunizing mice with MOG (35-55) peptide to induce experimental autoimmune encephalomyelitis (EAE), it causes inflammation (macrophages and CD3+ T lymphocytes), demyelination, and axonal loss [1]. MOG (35-55) is often used to model EAE in mice for evaluating various drug treatments [2].
Axon loss in the medial dorsal column (fasciculus gracilis), which is often damaged in this model of EAE, was detected as early as 7 days post-immunization (p.i.), with a loss of about 11% of axons in the defined counting area. A further 10% loss was observed by day 12 p.i., at which time behavioral disease was just beginning to become apparent [1]. T lymphocytes were detected infiltrating the spinal cord as early as day 7 p.i. CD3-immunoreactivity increased 5-fold [1]. MOG (35-55) immunized mice developed severe parenchymal infiltration in the spinal cords on day 9, day 13 and day 16, and mice showed heavy infiltration of the cerebral meninges, which prevailed in the region of the hippocampus involving the lateral and the third ventricle [3]. MOG (35-55)-induced EAE showed the cerebellar white matter infiltrates in all mice on days 13 and 16 [3].
References:
[1]. Jones M V, Nguyen T T, Deboy C A, et al. Behavioral and pathological outcomes in MOG 35-55 experimental autoimmune encephalomyelitis[J]. Journal of neuroimmunology, 2008, 199(1-2): 83-93.
[2]. Steinman L, Zamvil S S. Virtues and pitfalls of EAE for the development of therapies for multiple sclerosis[J]. Trends in immunology, 2005, 26(11): 565-571.
[3]. Kuerten S, Kostova-Bales D A, Frenzel L P, et al. MP4-and MOG: 35-55-induced EAE in C57BL/6 mice differentially targets brain, spinal cord and cerebellum[J]. Journal of neuroimmunology, 2007, 189(1-2): 31-40.
| Cas No. | 149635-73-4 | SDF | |
| 别名 | 髓鞘少突胶质细胞糖蛋白,endrocyte Glycoprotein Peptide (35-55) | ||
| 化学名 | (S)-2-((Z)-((2S,3R)-3-amino-1,2-dihydroxy-4-phenylbutylidene)amino)-4-methylpentanoic acid compound with 2,2,2-trifluoroacetic acid (1:1) | ||
| Canonical SMILES | CC(C[C@@](/N=C(O)/[C@](O)([H])[C@@](N)([H])CC1=CC=CC=C1)([H])C(O)=O)C.FC(F)(F)C(O)=O | ||
| 分子式 | C118H177N35O29S | 分子量 | 2581.97 |
| 溶解度 | ≥ 32.25mg/mL in Water, ≥ 86 mg/mL in DMSO | 储存条件 | Desiccate at -20°C |
| General tips | 请根据产品在不同溶剂中的溶解度选择合适的溶剂配制储备液；一旦配成溶液，请分装保存，避免反复冻融造成的产品失效。 储备液的保存方式和期限：-80°C 储存时，请在 6 个月内使用，-20°C 储存时，请在 1 个月内使用。 为了提高溶解度，请将管子加热至37℃，然后在超声波浴中震荡一段时间。 |
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| Shipping Condition | 评估样品解决方案：配备蓝冰进行发货。所有其他可用尺寸：配备RT，或根据请求配备蓝冰。 | ||
| 制备储备液 | |||
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1 mg | 5 mg | 10 mg |
| 1 mM | 0.3873 mL | 1.9365 mL | 3.873 mL |
| 5 mM | 0.0775 mL | 0.3873 mL | 0.7746 mL |
| 10 mM | 0.0387 mL | 0.1937 mL | 0.3873 mL |
| 第一步：请输入基本实验信息（考虑到实验过程中的损耗，建议多配一只动物的药量） | ||||||||||
| 给药剂量 | mg/kg |  |
动物平均体重 | g | |
每只动物给药体积 | ul | |
动物数量 | 只 |
| 第二步：请输入动物体内配方组成（配方适用于不溶于水的药物；不同批次药物配方比例不同，请联系GLPBIO为您提供正确的澄清溶液配方） | ||||||||||
| % DMSO % % Tween 80 % saline | ||||||||||
| 计算重置 | ||||||||||
计算结果:
工作液浓度： mg/ml；
DMSO母液配制方法： mg 药物溶于 μL DMSO溶液（母液浓度 mg/mL，
体内配方配制方法：取 μL DMSO母液，加入 μL PEG300，混匀澄清后加入μL Tween 80，混匀澄清后加入 μL saline，混匀澄清。
1. 首先保证母液是澄清的；
2.
一定要按照顺序依次将溶剂加入，进行下一步操作之前必须保证上一步操作得到的是澄清的溶液，可采用涡旋、超声或水浴加热等物理方法助溶。
3. 以上所有助溶剂都可在 GlpBio 网站选购。
The dermorphin peptide family
1. In 1980, the skin of certain frogs belonging to the genus Phyllomedusinae was found to contain two new peptides that proved to be selective mu-opioid agonists. Given the name dermorphins, these were the first members of a peptide family that in the past 15 years has grown to reach a total of seven naturally occurri
Active Induction of Experimental Autoimmune Encephalomyelitis (EAE) with MOG35-55 in the Mouse
Experimental autoimmune encephalomyelitis (EAE) is one of the most popular animal models of multiple sclerosis (MS). There are a number of EAE models, being actively induced EAE in strains such as C57Bl/6 mice very robust and reproducible. We herewith present details of the materials and methods for active EAE. Mice are immunized with an emulsion of myelin oligodendrocyte glycoprotein peptide 35-55 (MOG35-55) + complete Freund's adjuvant (supplemented with Mycobacterium tuberculosis), and treated with Bordetella pertussis toxin, to induce EAE. Sham-EAE mice are immunized with bovine serum albumin instead of MOG35-55.
DRα1-MOG-35-55 Reduces Permanent Ischemic Brain Injury
Stroke induces a catastrophic immune response that involves the global activation of peripheral leukocytes, especially T cells. The human leukocyte antigen-DRα1 domain linked to MOG-35-55 peptide (DRα1-MOG-35-55) is a partial major histocompatibility complex (MHC) class II construct which can inhibit neuroantigen-specific T cells and block binding of the cytokine/chemokine macrophage migration inhibitory factor (MIF) to its CD74 receptor on monocytes and macrophages. Here, we evaluated the therapeutic effect of DRα1-MOG-35-55 in a mouse model of permanent distal middle cerebral artery occlusion (dMCAO). DRα1-MOG-35-55 was administered to WT C57BL/6 mice by subcutaneous injection starting 4 h after the onset of ischemia followed by three daily injections. We demonstrated that DRα1-MOG-35-55 post treatment significantly reduced brain infarct volume, improved functional outcomes, and inhibited the accumulation of CD4+ and CD8+ T cells and expression of pro-inflammatory cytokines in the ischemic brain 96 h after dMCAO. In addition, DRα1-MOG-35-55 treatment shifted microglia/macrophages in the ischemic brain to a beneficial M2 phenotype without changing their total numbers in the brain or blood. This study demonstrates for the first time the therapeutic efficacy of the DRα1-MOG-35-55 construct in dMCAO across MHC class II barriers in C57BL/6 mice. This MHC-independent effect obviates the need for tissue typing and will thus greatly expedite treatment with DRα1-MOG-35-55 in human stroke subjects. Taken together, our findings suggest that DRα1-MOG-35-55 treatment may reduce ischemic brain injury by regulating post-stroke immune responses in the brain and the periphery.
DRα1-MOG-35-55 treatment reduces lesion volumes and improves neurological deficits after traumatic brain injury
Traumatic brain injury (TBI) results in severe neurological impairments without effective treatments. Inflammation appears to be an important contributor to key pathogenic events such as secondary brain injury following TBI and therefore serves as a promising target for novel therapies. We have recently demonstrated the ability of a molecular construct comprised of the human leukocyte antigen (HLA)-DRα1 domain linked covalently to mouse (m)MOG-35-55 peptide (DRα1-MOG-35-55 construct) to reduce CNS inflammation and tissue injury in animal models of multiple sclerosis and ischemic stroke. The aim of the current study was to determine if DRα1-MOG-35-55 treatment of a fluid percussion injury (FPI) mouse model of TBI could reduce the lesion size and improve disease outcome measures. Neurodeficits, lesion size, and immune responses were determined to evaluate the therapeutic potential and mechanisms of neuroprotection induced by DRα1-MOG-35-55 treatment. The results demonstrated that daily injections of DRα1-MOG-35-55 given after FPI significantly reduced numbers of infiltrating CD74+ and CD86+ macrophages and increased numbers of CD206+ microglia in the brain concomitant with smaller lesion sizes and improvement in neurodeficits. Conversely, DRα1-MOG-35-55 treatment of TBI increased numbers of circulating CD11b+ monocytes and their expression of CD74 but had no detectable effect on cell numbers or marker expression in the spleen. These results demonstrate that DRα1-MOG-35-55 therapy can reduce CNS inflammation and significantly improve histological and clinical outcomes after TBI. Future studies will further examine the potential of DRα1-MOG-35-55 for treatment of TBI.
Eosinophils are dispensable for development of MOG35-55-induced experimental autoimmune encephalomyelitis in mice
Experimental autoimmune encephalomyelitis (EAE) represents the mouse model of multiple sclerosis, a devastating neurological disorder. EAE development and progression involves the infiltration of different immune cells into the brain and spinal cord. However, less is known about a potential role of eosinophil granulocytes for EAE disease pathogenesis. In the present study, we found enhanced eosinophil abundance accompanied by increased concentration of the eosinophil chemoattractant eotaxin-1 in the spinal cord in the course of EAE induced in C57BL/6 mice by immunization with MOG35-55 peptide. However, the absence of eosinophils did not affect neuroinflammation, demyelination and clinical development or severity of EAE, as assessed in ?dblGATA1 eosinophil-deficient mice. Taken together, despite their enhanced abundance in the inflamed spinal cord during disease progression, eosinophils were dispensable for EAE development.
Oligodendrocyte-specific deletion of FGFR2 ameliorates MOG35-55 -induced EAE through ERK and Akt signalling
Fibroblast growth factors (FGFs) and their receptors (FGFRs) are involved in demyelinating pathologies including multiple sclerosis (MS). In our recent study, oligodendrocyte-specific deletion of FGFR1 resulted in a milder disease course, less inflammation, reduced myelin and axon damage in EAE. The objective of this study was to elucidate the role of oligodendroglial FGFR2 in MOG35-55 -induced EAE. Oligodendrocyte-specific knockout of FGFR2 (Fgfr2ind-/- ) was achieved by application of tamoxifen; EAE was induced using the MOG35-55 peptide. EAE symptoms were monitored over 62 days. Spinal cord tissue was analysed by histology, immunohistochemistry and western blot. Fgfr2ind-/- mice revealed a milder disease course, less myelin damage and enhanced axonal density. The number of oligodendrocytes was not affected in demyelinated areas. However, protein expression of FGFR2, FGF2 and FGF9 was downregulated in Fgfr2ind-/- mice. FGF/FGFR dependent signalling proteins were differentially regulated; pAkt was upregulated and pERK was downregulated in Fgfr2ind-/- mice. The number of CD3(+) T cells, Mac3(+) cells and B220(+) B cells was less in demyelinated lesions of Fgfr2ind-/- mice. Furthermore, expression of IL-1β, TNF-α and CD200 was less in Fgfr2ind-/- mice than controls. Fgfr2ind-/- mice showed an upregulation of PLP and downregulation of the remyelination inhibitors SEMA3A and TGF-β expression. These data suggest that cell-specific deletion of FGFR2 in oligodendrocytes has anti-inflammatory and neuroprotective effects accompanied by changes in FGF/FGFR dependent signalling, inflammatory cytokines and expression of remyelination inhibitors. Thus, FGFRs in oligodendrocytes may represent potential targets for the treatment of inflammatory and demyelinating diseases including MS.
Active Induction of Experimental Autoimmune Encephalomyelitis (EAE) with MOG35-55 in the Mouse
Experimental autoimmune encephalomyelitis (EAE) is one of the most popular animal models of multiple sclerosis (MS). There are a number of EAE models, being actively induced EAE in strains such as C57Bl/6 mice very robust and reproducible. We herewith present details of the materials and methods for active EAE. Mice are immunized with an emulsion of myelin oligodendrocyte glycoprotein peptide 35-55 (MOG35-55) + complete Freund's adjuvant (supplemented with Mycobacterium tuberculosis), and treated with Bordetella pertussis toxin, to induce EAE. Sham-EAE mice are immunized with bovine serum albumin instead of MOG35-55.
DRα1-MOG-35-55 Reduces Permanent Ischemic Brain Injury
Stroke induces a catastrophic immune response that involves the global activation of peripheral leukocytes, especially T cells. The human leukocyte antigen-DRα1 domain linked to MOG-35-55 peptide (DRα1-MOG-35-55) is a partial major histocompatibility complex (MHC) class II construct which can inhibit neuroantigen-specific T cells and block binding of the cytokine/chemokine macrophage migration inhibitory factor (MIF) to its CD74 receptor on monocytes and macrophages. Here, we evaluated the therapeutic effect of DRα1-MOG-35-55 in a mouse model of permanent distal middle cerebral artery occlusion (dMCAO). DRα1-MOG-35-55 was administered to WT C57BL/6 mice by subcutaneous injection starting 4 h after the onset of ischemia followed by three daily injections. We demonstrated that DRα1-MOG-35-55 post treatment significantly reduced brain infarct volume, improved functional outcomes, and inhibited the accumulation of CD4+ and CD8+ T cells and expression of pro-inflammatory cytokines in the ischemic brain 96 h after dMCAO. In addition, DRα1-MOG-35-55 treatment shifted microglia/macrophages in the ischemic brain to a beneficial M2 phenotype without changing their total numbers in the brain or blood. This study demonstrates for the first time the therapeutic efficacy of the DRα1-MOG-35-55 construct in dMCAO across MHC class II barriers in C57BL/6 mice. This MHC-independent effect obviates the need for tissue typing and will thus greatly expedite treatment with DRα1-MOG-35-55 in human stroke subjects. Taken together, our findings suggest that DRα1-MOG-35-55 treatment may reduce ischemic brain injury by regulating post-stroke immune responses in the brain and the periphery.
DRα1-MOG-35-55 treatment reduces lesion volumes and improves neurological deficits after traumatic brain injury
Traumatic brain injury (TBI) results in severe neurological impairments without effective treatments. Inflammation appears to be an important contributor to key pathogenic events such as secondary brain injury following TBI and therefore serves as a promising target for novel therapies. We have recently demonstrated the ability of a molecular construct comprised of the human leukocyte antigen (HLA)-DRα1 domain linked covalently to mouse (m)MOG-35-55 peptide (DRα1-MOG-35-55 construct) to reduce CNS inflammation and tissue injury in animal models of multiple sclerosis and ischemic stroke. The aim of the current study was to determine if DRα1-MOG-35-55 treatment of a fluid percussion injury (FPI) mouse model of TBI could reduce the lesion size and improve disease outcome measures. Neurodeficits, lesion size, and immune responses were determined to evaluate the therapeutic potential and mechanisms of neuroprotection induced by DRα1-MOG-35-55 treatment. The results demonstrated that daily injections of DRα1-MOG-35-55 given after FPI significantly reduced numbers of infiltrating CD74+ and CD86+ macrophages and increased numbers of CD206+ microglia in the brain concomitant with smaller lesion sizes and improvement in neurodeficits. Conversely, DRα1-MOG-35-55 treatment of TBI increased numbers of circulating CD11b+ monocytes and their expression of CD74 but had no detectable effect on cell numbers or marker expression in the spleen. These results demonstrate that DRα1-MOG-35-55 therapy can reduce CNS inflammation and significantly improve histological and clinical outcomes after TBI. Future studies will further examine the potential of DRα1-MOG-35-55 for treatment of TBI.
Eosinophils are dispensable for development of MOG35-55-induced experimental autoimmune encephalomyelitis in mice
Experimental autoimmune encephalomyelitis (EAE) represents the mouse model of multiple sclerosis, a devastating neurological disorder. EAE development and progression involves the infiltration of different immune cells into the brain and spinal cord. However, less is known about a potential role of eosinophil granulocytes for EAE disease pathogenesis. In the present study, we found enhanced eosinophil abundance accompanied by increased concentration of the eosinophil chemoattractant eotaxin-1 in the spinal cord in the course of EAE induced in C57BL/6 mice by immunization with MOG35-55 peptide. However, the absence of eosinophils did not affect neuroinflammation, demyelination and clinical development or severity of EAE, as assessed in ?dblGATA1 eosinophil-deficient mice. Taken together, despite their enhanced abundance in the inflamed spinal cord during disease progression, eosinophils were dispensable for EAE development.
Oligodendrocyte-specific deletion of FGFR2 ameliorates MOG35-55 -induced EAE through ERK and Akt signalling
Fibroblast growth factors (FGFs) and their receptors (FGFRs) are involved in demyelinating pathologies including multiple sclerosis (MS). In our recent study, oligodendrocyte-specific deletion of FGFR1 resulted in a milder disease course, less inflammation, reduced myelin and axon damage in EAE. The objective of this study was to elucidate the role of oligodendroglial FGFR2 in MOG35-55 -induced EAE. Oligodendrocyte-specific knockout of FGFR2 (Fgfr2ind-/- ) was achieved by application of tamoxifen; EAE was induced using the MOG35-55 peptide. EAE symptoms were monitored over 62 days. Spinal cord tissue was analysed by histology, immunohistochemistry and western blot. Fgfr2ind-/- mice revealed a milder disease course, less myelin damage and enhanced axonal density. The number of oligodendrocytes was not affected in demyelinated areas. However, protein expression of FGFR2, FGF2 and FGF9 was downregulated in Fgfr2ind-/- mice. FGF/FGFR dependent signalling proteins were differentially regulated; pAkt was upregulated and pERK was downregulated in Fgfr2ind-/- mice. The number of CD3(+) T cells, Mac3(+) cells and B220(+) B cells was less in demyelinated lesions of Fgfr2ind-/- mice. Furthermore, expression of IL-1β, TNF-α and CD200 was less in Fgfr2ind-/- mice than controls. Fgfr2ind-/- mice showed an upregulation of PLP and downregulation of the remyelination inhibitors SEMA3A and TGF-β expression. These data suggest that cell-specific deletion of FGFR2 in oligodendrocytes has anti-inflammatory and neuroprotective effects accompanied by changes in FGF/FGFR dependent signalling, inflammatory cytokines and expression of remyelination inhibitors. Thus, FGFRs in oligodendrocytes may represent potential targets for the treatment of inflammatory and demyelinating diseases including MS.
Dermorphin tetrapeptide analogs as potent and long-lasting analgesics with pharmacological profiles distinct from morphine
Dermorphin (Tyr-d-Ala-Phe-Gly-Tyr-Pro-Ser-NH(2)) is a heptapeptide isolated from amphibian skin. With a very high affinity and selectivity for μ-opioid receptors, dermorphin shows an extremely potent antinociceptive effect. The structure-activity relationship studies of dermorphin analogs clearly suggest that the N-terminal tetrapeptide is the minimal sequence for agonistic activity at μ-opioid receptors, and that the replacement of the d-Ala(2) residue with d-Arg(2) makes the tetrapeptides resistant to enzymatic metabolism. At present, only a handful of dermorphin N-terminal tetrapeptide analogs containing d-Arg(2) have been developed. The analogs show potent antinociceptive activity that is greater than that of morphine with various injection routes, and retain high affinity and selectivity for μ-opioid receptors. Interestingly, some analogs show pharmacological profiles that are distinct from the traditional μ-opioid receptor agonists morphine and [d-Ala(2),NMePhe(4),Gly-ol(5)]enkephalin (DAMGO). These analogs stimulate the release of dynorphins through the activation of μ-opioid receptors. The activation of κ-opioid receptors by dynorphins is suggested to reduce the side effects of μ-opioid receptor agonists, e.g., dependence or antinociceptive tolerance. The dermorphin N-terminal tetrapeptide analogs containing d-Arg(2) may provide a new target molecule for developing novel analgesics that have fewer side effects.
Rediscovery of old drugs: the forgotten case of dermorphin for postoperative pain and palliation
The repurposing of old drugs for new indications is becoming more accepted as a cost-efficient solution for complicated health problems. However, older drugs are often forgotten when they are not repositioned. This analysis makes a case for re-exploration of dermorphin for intrathecal use in postoperative pain and in a palliative context, with the goal of re-establishing this compound. Dermorphin was isolated from the skin of an Amazonian frog, characterized and identified as a bioactive heptapeptide by Vittorio Erspamer's research group in the early 1980s. It was traditionally called "Kambo" or "Sapo" by Amazon tribes and was used to improve their physical and psychic skills as hunters. Its structure is rather enigmatic, containing a D-amino acid, and its pharmacological activity in a number of assays was found to be quite impressive and superior to morphine. Moreover, it has been established as more selective and potent with long-lasting analgesia compared to morphine after intracerebroventricular administration in animal models. In 1985, the first clinical trial results of a randomized, placebo-controlled study in postoperative pain were reported, and dermorphin administered via the intrathecal route was again impressively superior over the placebo and the reference compound morphine. This milestone study was apparently minimally read by clinicians, as the study has never been referenced; only 15 pharmacological and review papers after 1985 mentioned the results, with not one being a clinical paper. The interest in dermorphin decreased after 1985, and the compound was never again introduced in the clinical setting. Considering the enormous pressure to find superior acting opioids, this is quite puzzling. We suggest new clinical studies to further evaluate the safety and efficacy of dermorphin, especially administered via the intrathecal route in postoperative pain or for palliative use in terminal patients.
Evaluation of Dermorphin Metabolism Using Zebrafish Water Tank Model and Human Liver Microsomes
Background: Dermorphin is a heptapeptide with an analgesic potential higher than morphine that does not present the same risk for the development of tolerance. These pharmacological features make dermorphin a potential doping agent in competitive sports and it is already prohibited for racehorses. For athletes, the development of an efficient strategy to monitor for its abuse necessitates an investigation of the metabolism of dermorphin in humans.
Methods: Here, human liver microsomes and zebrafish were utilized as model systems of human metabolism to evaluate the presence and kinetics of metabolites derived from dermorphin. Five hours after its administration, the presence of dermorphin metabolites could be detected in both models by liquid chromatography coupled to highresolution mass spectrometry.
Results: Although the two models showed common results, marked differences were also observed in relation to the formed metabolites. Six putative metabolites, based on their exact masses of m/z 479.1915, m/z 501.1733, m/z 495.1657, m/z 223.1073, m/z 180.1017 and m/z 457.2085, are proposed to represent the metabolic pattern of dermorphin. The major metabolite generated from the administration of dermorphin in both models was YAFG-OH (m/z 457.2085), which is the N-terminal tetrapeptide previously identified from studies on rats.
Conclusion: Its extensive characterization and commercial availability suggest that it could serve as a primary target analyte for the detection of dermorphin misuse. The metabolomics approach also allowed the assignment of other confirmatory metabolites.
Pharmacokinetics and pharmacodynamics of dermorphin in the horse
Dermorphin is a μ-opioid receptor-binding peptide that causes both central and peripheral effects following intravenous administration to rats, dogs, and humans and has been identified in postrace horse samples. Ten horses were intravenously and/or intramuscularly administered dermorphin (9.3 ± 1.0 μg/kg), and plasma concentration vs. time data were evaluated using compartmental and noncompartmental analyses. Data from intravenous administrations fit a 2-compartment model best with distribution and elimination half-lives (harmonic mean ± pseudo SD) of 0.09 ± 0.02 and 0.76 ± 0.22 h, respectively. Data from intramuscular administrations fit a noncompartmental model best with a terminal elimination half-life of 0.68 ± 0.24 (h). Bioavailability following intramuscular administration was variable (47-100%, n = 3). The percentage of dermorphin excreted in urine was 5.0 (3.7-10.6) %. Excitation accompanied by an increased heart rate followed intravenous administration only and subsided after 5 min. A plot of the mean change in heart rate vs. the plasma concentration of dermorphin fit a hyperbolic equation (simple Emax model), and an EC(50) of 21.1 ± 8.8 ng/mL was calculated. Dermorphin was detected in plasma for 12 h and in urine for 48 or 72 h following intravenous or intramuscular administration, respectively.