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1.
Rev Med Suisse ; 16(689): 679-682, 2020 Apr 08.
Artigo em Francês | MEDLINE | ID: mdl-32270934

RESUMO

Since the description in 2015 of the MRGPRX2 receptor on mast cells, responsible for pseudo-allergies, our knowledge of this type of allergy-like drug reaction is growing, as has the list of drugs -supposed to be able to induce this type of reaction. Unlike IgE--mediated reactions, these pseudoallergic reactions do not require a prior sensitization, are dose-dependent and predictable, and could be prevented, if the offending drug has to be re-administered, -simply with a reduced rate of perfusion or dose. Genetic factors seem to play a role in the predisposition to this type of reactions, but we do not yet have clinically available tools to diagnose them. This literature review summarizes the discoveries of the last 4 years in this field that seem to challenge many dogmas in allergology.


Assuntos
Degranulação Celular , Hipersensibilidade a Drogas , Mastócitos/metabolismo , Degranulação Celular/efeitos dos fármacos , Relação Dose-Resposta Imunológica , Hipersensibilidade a Drogas/genética , Hipersensibilidade a Drogas/metabolismo , Humanos , Proteínas do Tecido Nervoso/metabolismo , Receptores Acoplados a Proteínas-G/metabolismo , Receptores de Neuropeptídeos/metabolismo
2.
Gene ; 743: 144605, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32199950

RESUMO

Atrijuglans hetaohei Yang (Lepidoptera: Gelechioidea), is one of the major pests that can seriously damage the walnut fruits. Neuropeptides and their receptors regulate most physiological functions in insects and represent new targets for the development of control agents. To identify the neuropeptides and their receptors from A. hetaohei, we sequenced and analyzed its head transcriptomic data, identified 32 neuropeptides and 39 neuropeptide receptor genes. Sequence comparisons and phylogenetic analyses suggest that A. hetaohei neuropeptides and receptor genes have high homology with those in Bombyx mori, Chilo suppressalis, Plutella xylostella and Helicoverpa armigera. Moreover, gene expression patterns revealed that neuropeptide genes such as AKH1, CP, MS and PTTH were expressed specifically in male head, while CAP3, DH, NPLP1, PBAN and SIF showed higher expression in the female head. Bur showed abdomen biased expression in both male and female. Neuropeptide receptor genes such as A8, A11, A15 and LGR were highly expressed in male head, whereas A24 and LGR2 were preferentially expressed in female head. This is the first sequencing, identification and expression analyses of neuropeptides and neuropeptide receptor genes from A. hetaohei. Our results could provide a powerful background that will facilitate the further investigations using transcriptomics to determine neuropeptides and their receptors presence, functions, and indicates potential targets in A. hetaohei for a novel pest management strategy.


Assuntos
Proteínas de Insetos/genética , Mariposas/genética , Neuropeptídeos/genética , Receptores de Neuropeptídeos/genética , Transcriptoma/genética , Animais , Clonagem Molecular , Feminino , Perfilação da Expressão Gênica , Genes de Insetos , Juglans/parasitologia , Masculino , Controle de Pragas/métodos , Filogenia , Fatores Sexuais
3.
Immunity ; 52(2): 404-416.e5, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32049054

RESUMO

Mast cells are rare tissue-resident cells of importance to human allergies. To understand the structural basis of principle mast cell functions, we analyzed the proteome of primary human and mouse mast cells by quantitative mass spectrometry. We identified a mast-cell-specific proteome signature, indicative of a unique lineage, only distantly related to other immune cell types, including innate immune cells. Proteome comparison between human and mouse suggested evolutionary conservation of core mast cell functions. In addition to specific proteases and proteins associated with degranulation and proteoglycan biosynthesis, mast cells expressed proteins potentially involved in interactions with neurons and neurotransmitter metabolism, including cell adhesion molecules, ion channels, and G protein coupled receptors. Toward targeted cell ablation in severe allergic diseases, we used MRGPRX2 for mast cell depletion in human skin biopsies. These proteome analyses suggest a unique role of mast cells in the immune system, probably intertwined with the nervous system.


Assuntos
Mastócitos/citologia , Mastócitos/imunologia , Animais , Biomarcadores/metabolismo , Degranulação Celular , Linhagem da Célula , Células Cultivadas , Tecido Conjuntivo/imunologia , Humanos , Imunoterapia , Mastócitos/metabolismo , Proteínas de Membrana/imunologia , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/imunologia , Proteínas do Tecido Nervoso/metabolismo , Neuroimunomodulação , Proteoglicanas/biossíntese , Proteoma , Receptores Acoplados a Proteínas-G/imunologia , Receptores Acoplados a Proteínas-G/metabolismo , Receptores de Neuropeptídeos/imunologia , Receptores de Neuropeptídeos/metabolismo , Pele/imunologia
4.
Phytomedicine ; 68: 153149, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32032836

RESUMO

BACKGROUND: Mast cells (MCs) are crucial effectors in allergic disorders by secreting inflammatory mediators. The Mas-related G-protein-coupled receptor X2 (Mrgprx2) was shown to have a key role in IgE-independent allergic reactions. Therefore, potential drug candidates that directly target Mrgprx2 could be used to treat pseudo-allergic diseases. Shikonin, an active ingredient derived from Lithospermum erythrorhizon Sieb. et Zucc has been used for its anti-inflammatory properties since ancient China. PURPOSE: To investigate the inhibitory effects of Shikonin on IgE-independent allergy both in vitro and in vivo, as well as the mechanism underlying its effects. METHODS/STUDY DESIGNS: The anti-anaphylactoid activity of Shikonin was evaluated in PCA and systemic anaphylaxis models, Calcium imaging was used to assess intracellular Ca2+ mobilization. The release of cytokines and chemokines was measured using enzyme immunoassay kits. Western blot analysis was conducted to investigate the molecules of PLCγ-PKC-IP3 signaling pathway. The analytical method of surface plasmon resonance was employed to study the interaction between Shikonin and potential target protein Mrgprx2. RESULTS: Shikonin can suppress compound 48/80 (C48/80)-induced PCA, active systemic anaphylaxis, and MCs degranulation in mice in a dose-dependent manner. In addition, Shikonin reduced C48/80-induced calcium flux and suppressed LAD2 cell degranulation via PLCγ-PKC-IP3 signaling pathway. Moreover, Shikonin was found to inhibit C48/80-induced Mrgprx2 expression in HEK cells, displaying specific interactions with the Mrgprx2 protein. CONCLUSION: Shikonin could be a potential antagonist of Mrgprx2, thereby inhibiting pseudo-allergic reactions through Ca2+ mobilization.


Assuntos
Anafilaxia/tratamento farmacológico , Hipersensibilidade/tratamento farmacológico , Naftoquinonas/farmacologia , Proteínas do Tecido Nervoso/imunologia , Receptores Acoplados a Proteínas-G/imunologia , Receptores de Neuropeptídeos/imunologia , Anafilaxia/induzido quimicamente , Animais , Cálcio/metabolismo , Degranulação Celular/efeitos dos fármacos , Linhagem Celular , Quimiocinas/metabolismo , Citocinas/metabolismo , Humanos , Hipersensibilidade/imunologia , Masculino , Mastócitos/efeitos dos fármacos , Mastócitos/metabolismo , Camundongos Endogâmicos C57BL , Naftoquinonas/química , Proteínas do Tecido Nervoso/antagonistas & inibidores , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/metabolismo , Fosfolipase C gama/metabolismo , Receptores Acoplados a Proteínas-G/antagonistas & inibidores , Receptores Acoplados a Proteínas-G/química , Receptores Acoplados a Proteínas-G/metabolismo , Receptores de Neuropeptídeos/antagonistas & inibidores , Receptores de Neuropeptídeos/química , Receptores de Neuropeptídeos/metabolismo , Secretagogos/toxicidade , p-Metoxi-N-metilfenetilamina/toxicidade
5.
PLoS One ; 15(1): e0227666, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31945099

RESUMO

Species-specific sex pheromones play key roles in moth sexual communication. Although the general pathway of Type-I sex pheromone biosynthesis is well established, only a handful of genes encoding enzymes involved in this pathway have been characterized. Streltzoviella insularis is a destructive wood-boring pest of many street trees in China, and the female sex pheromone of this species comprises a blend of (Z)-3-tetradecenyl acetate, (E)-3-tetradecenyl acetate, and (Z)-5-dodecenyl acetate. This organism therefore provides an excellent model for research on the diversity of genes and molecular mechanisms involved in pheromone production. Herein, we assembled the pheromone gland transcriptome of S. insularis by next-generation sequencing and identified 74 genes encoding candidate key enzymes involved in the fatty acid biosynthesis, ß-oxidation, and functional group modification. In addition, tissue expression patterns further showed that an acetyl-CoA carboxylase and two desaturases were highly expressed in the pheromone glands compared with the other tissues, indicating possible roles in S. insularis sex pheromone biosynthesis. Finally, we proposed putative S. insularis biosynthetic pathways for sex pheromone components and highlighted candidate genes. Our findings lay a solid foundation for understanding the molecular mechanisms underpinning S. insularis sex pheromone biosynthesis, and provide potential targets for disrupting chemical communication that could assist the development of novel pest control methods.


Assuntos
Genes de Insetos , Mariposas/genética , Mariposas/metabolismo , Atrativos Sexuais/biossíntese , Atrativos Sexuais/genética , Acetil-CoA Carboxilase/genética , Acetil-CoA Carboxilase/metabolismo , Acetiltransferases/genética , Acetiltransferases/metabolismo , Álcool Desidrogenase/genética , Álcool Desidrogenase/metabolismo , Aldeído Oxirredutases/genética , Aldeído Oxirredutases/metabolismo , Aldeído Redutase/genética , Aldeído Redutase/metabolismo , Animais , Vias Biossintéticas/genética , China , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Dessaturases/metabolismo , Ácido Graxo Sintases/genética , Ácido Graxo Sintases/metabolismo , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Filogenia , Receptores de Neuropeptídeos/genética , Receptores de Neuropeptídeos/metabolismo , Glândulas Odoríferas/metabolismo , Análise de Sequência de RNA , Transcriptoma
6.
Expert Rev Gastroenterol Hepatol ; 14(2): 103-111, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31996050

RESUMO

Introduction: Motilin was first alluded to nearly a century ago. But it remains a rather abstruse peptide, in the shadow of its younger but more lucid 'cousin' ghrelin.Areas covered: The review aimed to bring to the fore multifarious aspects of motilin research with a view to aiding prioritization of future studies on this gastrointestinal peptide.Expert opinion: Growing evidence indicates that rodents (mice, rats, guinea pigs) do not have functional motilin system and, hence, studies in these species are likely to have a minimal translational impact. Both the active peptide and motilin receptor were initially localized to the upper gastrointestinal tract only but more recently - also to the brain (in both humans and other mammals with functional motilin system). Motilin is now indisputably implicated in interdigestive contractile activity of the gastrointestinal tract (in particular, gastric phase III of the migrating motor complex). Beyond this role, evidence is building that there is a cross-talk between motilin system and the brain-pancreas axis, suggesting that motilin exerts not only contractile but also orexigenic and insulin secretagogue actions.


Assuntos
Encéfalo/fisiologia , Trato Gastrointestinal/fisiologia , Motilina/fisiologia , Pâncreas/fisiologia , Animais , Motilidade Gastrointestinal/fisiologia , Grelina/fisiologia , Humanos , Fome/fisiologia , Insulina/fisiologia , Complexo Mioelétrico Migratório/fisiologia , Receptor Cross-Talk/fisiologia , Receptores dos Hormônios Gastrointestinais/fisiologia , Receptores de Neuropeptídeos/fisiologia , Transdução de Sinais/fisiologia
7.
Phytother Res ; 34(2): 401-408, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31667930

RESUMO

Mas-related G protein-coupled receptor-X2 (MRGPRX2) expressed on mast cells (MCs) has been shown to be a pivotal target for pseudo-allergic diseases. Therefore, MRGPRX2 might be a therapeutic target for allergic contact dermatitis, atopic dermatitis, and red man syndrome. Paeoniflorin (PF) was reported to have an antiinflammatory effect in neuroinflammation, enteritis, and so forth. In this study, we investigated the anti-pseudo-allergic effect of PF and the underlying molecular mechanisms. Our results showed that PF can suppress compound 48/80 (C48/80)-induced PCA and MCs degranulation in vivo, in a dose-dependent manner. Moreover, PF can reduce C48/80-induced calcium influx and suppress MC degranulation and chemokines release in vitro. PF can downregulate the phosphorylation levels of key kinases in PLCγ-regulated calcium influx and subsequent cytokine synthesis pathways. Our study revealed that PF could inhibit C48/80-induced allergic responses both in vivo and in vitro. As such, it may be regarded as a novel inhibitor for preventing MRGPRX2-mediated allergic diseases.


Assuntos
Antialérgicos/uso terapêutico , Sinalização do Cálcio/efeitos dos fármacos , Glucosídeos/uso terapêutico , Hipersensibilidade/tratamento farmacológico , Mastócitos/efeitos dos fármacos , Monoterpenos/uso terapêutico , Proteínas do Tecido Nervoso/metabolismo , Receptores Acoplados a Proteínas-G/metabolismo , Receptores de Neuropeptídeos/metabolismo , Animais , Degranulação Celular/efeitos dos fármacos , Quimiocinas/metabolismo , Citocinas/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL
8.
Arch Insect Biochem Physiol ; 103(2): e21625, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31565815

RESUMO

In insects, neuropeptides constitute a group of signaling molecules that act in regulation of multiple physiological and behavioral processes by binding to their corresponding receptors. On the basis of the bioinformatic approaches, we screened the genomic and transcriptomic data of the parasitoid wasp, Pteromalus puparum, and annotated 36 neuropeptide precursor genes and 33 neuropeptide receptor genes. Compared to the number of precursor genes in Bombyx mori (Lepidoptera), Chilo suppressalis (Lepidoptera), Drosophila melanogaster (Diptera), Nilaparvata lugens (Hemiptera), Apis mellifera (Hymenoptera), and Tribolium castaneum (Coleoptera), P. puparum (Hymenoptera) has the lowest number of neuropeptide precursor genes. This lower number may relate to its parasitic life cycle. Transcriptomic data of embryos, larvae, pupae, adults, venom glands, salivary glands, ovaries, and the remaining carcass revealed stage-, sex-, and tissue-specific expression patterns of the neuropeptides, and their receptors. These data provided basic information about the identity and expression profiles of neuropeptides and their receptors that are required to functionally address their biological significance in an endoparasitoid wasp.


Assuntos
Proteínas de Insetos/genética , Neuropeptídeos/genética , Receptores de Neuropeptídeos/genética , Vespas/genética , Sequência de Aminoácidos , Animais , Embrião não Mamífero/química , Embrião não Mamífero/metabolismo , Feminino , Perfilação da Expressão Gênica , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Larva/genética , Larva/metabolismo , Masculino , Neuropeptídeos/química , Neuropeptídeos/metabolismo , Filogenia , Pupa/genética , Pupa/metabolismo , Receptores de Neuropeptídeos/química , Receptores de Neuropeptídeos/metabolismo , Alinhamento de Sequência , Vespas/crescimento & desenvolvimento , Vespas/metabolismo
9.
Proc Natl Acad Sci U S A ; 117(2): 1097-1106, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31843923

RESUMO

The molecular mechanisms by which animals integrate external stimuli with internal energy balance to regulate major developmental and reproductive events still remain enigmatic. We investigated this aspect in the marine bristleworm, Platynereis dumerilii, a species where sexual maturation is tightly regulated by both metabolic state and lunar cycle. Our specific focus was on ligands and receptors of the gonadotropin-releasing hormone (GnRH) superfamily. Members of this superfamily are key in triggering sexual maturation in vertebrates but also regulate reproductive processes and energy homeostasis in invertebrates. Here we show that 3 of the 4 gnrh-like (gnrhl) preprohormone genes are expressed in specific and distinct neuronal clusters in the Platynereis brain. Moreover, ligand-receptor interaction analyses reveal a single Platynereis corazonin receptor (CrzR) to be activated by CRZ1/GnRHL1, CRZ2/GnRHL2, and GnRHL3 (previously classified as AKH1), whereas 2 AKH-type hormone receptors (GnRHR1/AKHR1 and GnRHR2/AKHR2) respond only to a single ligand (GnRH2/GnRHL4). Crz1/gnrhl1 exhibits a particularly strong up-regulation in sexually mature animals, after feeding, and in specific lunar phases. Homozygous crz1/gnrhl1 knockout animals exhibit a significant delay in maturation, reduced growth, and attenuated regeneration. Through a combination of proteomics and gene expression analysis, we identify enzymes involved in carbohydrate metabolism as transcriptional targets of CRZ1/GnRHL1 signaling. Our data suggest that Platynereis CRZ1/GnRHL1 coordinates glycoprotein turnover and energy homeostasis with growth and sexual maturation, integrating both metabolic and developmental demands with the worm's monthly cycle.


Assuntos
Hormônio Liberador de Gonadotropina/metabolismo , Homeostase , Proteínas de Insetos/metabolismo , Lua , Neuropeptídeos/metabolismo , Poliquetos/fisiologia , Maturidade Sexual/fisiologia , Transdução de Sinais/fisiologia , Animais , Encéfalo , Proteínas de Ligação a DNA/genética , Técnicas de Silenciamento de Genes , Hormônio Liberador de Gonadotropina/genética , Hormônios de Inseto/genética , Hormônios de Inseto/metabolismo , Proteínas de Insetos/genética , Invertebrados/genética , Neuropeptídeos/genética , Filogenia , Poliquetos/genética , Poliquetos/crescimento & desenvolvimento , Receptores de Neuropeptídeos , Receptores de Peptídeos/genética , Transdução de Sinais/genética , Fatores de Transcrição
10.
Gen Comp Endocrinol ; 285: 113294, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31585115

RESUMO

Motilin and ghrelin were identified in the pheasant by molecular cloning, and the actions of both peptides on the contractility of gastrointestinal (GI) strips were examined in vitro. Molecular cloning indicated that the deduced amino acid sequences of the pheasant motilin and ghrelin were a 22-amino acid peptide, FVPFFTQSDIQKMQEKERIKGQ, and a 26-amino acid peptide, GSSFLSPAYKNIQQQKDTRKPTGRLH, respectively. In in vitro studies using pheasant GI strips, chicken motilin caused contraction of the proventriculus and small intestine, whereas the crop and colon were insensitive. Human motilin, but not erythromycin, caused contraction of small intestine. Chicken motilin-induced contractions in the proventriculus and ileum were not inhibited by a mammalian motilin receptor antagonist, GM109. Neither atropine (a cholinergic receptor antagonist) nor tetrodotoxin (a neuron blocker) inhibited the responses of chicken motilin in the ileum but both drugs decreased the responses to motilin in the proventriculus, suggesting that the contractile mechanisms of motilin in the proventriculus was neurogenic, different from that of the small intestine (myogenic). On the other hand, chicken and quail ghrelin did not cause contraction in any regions of pheasant GI tract. Since interaction of ghrelin and motilin has been reported in the house musk shrew, interaction of two peptides was examined. The chicken motilin-induced contractions were not modified by ghrelin, and ghrelin also did not cause any contraction under the presence of motilin, suggesting the absence of interaction in both peptides. In conclusion, both the motilin system and ghrelin system are present in the pheasant. Regulation of GI motility by motilin might be common in avian species. However, absence of ghrelin actions in any GI regions suggests the avian species-related difference in regulation of GI contractility by ghrelin.


Assuntos
Aves/metabolismo , Trato Gastrointestinal/fisiologia , Grelina/farmacologia , Motilina/farmacologia , Contração Muscular/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Atropina/farmacologia , Sequência de Bases , Galinhas , Clonagem Molecular , Feminino , Motilidade Gastrointestinal/efeitos dos fármacos , Motilidade Gastrointestinal/fisiologia , Trato Gastrointestinal/efeitos dos fármacos , Grelina/química , Grelina/genética , Humanos , Masculino , Motilina/química , Motilina/genética , Proventrículo/efeitos dos fármacos , Codorniz , Ratos , Receptores dos Hormônios Gastrointestinais/metabolismo , Receptores de Neuropeptídeos/metabolismo , Tetrodotoxina/farmacologia
11.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1134-1135: 121875, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31790916

RESUMO

The nonpeptide small molecule, MES207, exhibits 17-fold preferential binding to the neuropeptide FF receptor 1 (NPFFR1) over NPFFR2 and shows antagonist functionality at NPFF receptors. In order to further the development of MES207 as a NPFFR1 probe, an UPLC-MS/MS bioanalytical method was developed and validated to quantify MES207 in rat plasma for a linearity range of 3-200 ng/mL. The method was applied in the analysis of the plasma, brain, and urine samples collected during pharmacokinetic studies in healthy male and female Sprague Dawley rats. The animals were dosed through oral gavage (50 mg/kg) and intravenously (2.5 mg/kg). Test samples were analyzed using the validated bioanalytical method to generate plasma concentration-time profiles. The results were further subjected to non-compartmental analysis using Phoenix 6.4®. MES207 exhibits a large volume of distribution (1.2 ±â€¯0.6 L), high clearance (0.8 ±â€¯0.1 L/h), and a poor oral bioavailability (1.7 ±â€¯0.4%). The compound also showed a multiple peak phenomenon with a very short absorption phase. It appears that gender does not significantly influence the differences in pharmacokinetic parameters of this NPFF probe.


Assuntos
Guanidinas/sangue , Guanidinas/farmacocinética , Piperidinas/sangue , Piperidinas/farmacocinética , Receptores de Neuropeptídeos/antagonistas & inibidores , Animais , Cromatografia Líquida de Alta Pressão/métodos , Estabilidade de Medicamentos , Feminino , Guanidinas/química , Limite de Detecção , Modelos Lineares , Masculino , Piperidinas/química , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
12.
Int J Mol Sci ; 20(21)2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31652731

RESUMO

The neuropeptide substance P (SP) contributes to neurogenic inflammation through the activation of human mast cells via Mas-related G protein-coupled receptor-X2 (MRGPRX2). Using pertussis toxins and YM-254890, we demonstrated that SP induces Ca2+ mobilization and degranulation via both the Gαi and Gαq family of G proteins in rat basophilic leukemia (RBL-2H3) cells stably expressing MRGPRX2. To determine the roles of MRGPRX2's transmembrane (TM) and intracellular domains on SP-induced responses, we utilized information obtained from both structural modeling and naturally occurring MRGPRX2 missense variants. We found that highly conserved residues in TM6 (I225) and TM7 (Y279) of MRGPRX2 are essential for SP-induced Ca2+ mobilization and degranulation in transiently transfected RBL-2H3 cells. Cells expressing missense variants in the receptor's conserved residues (V123F and V282M) as well as intracellular loops (R138C and R141C) failed to respond to SP. By contrast, replacement of all five Ser/Thr residues with Ala and missense variants (S325L and L329Q) in MRGPRX2's carboxyl-terminus resulted in enhanced mast cell activation by SP when compared to the wild-type receptor. These findings suggest that MRGPRX2 utilizes conserved residues in its TM domains and intracellular loops for coupling to G proteins and likely undergoes desensitization via phosphorylation at Ser/Thr residues in its carboxyl-terminus. Furthermore, identification of gain and loss of function MRGPRX2 variants has important clinical implications for SP-mediated neurogenic inflammation and other chronic inflammatory diseases.


Assuntos
Mutação com Ganho de Função , Mutação com Perda de Função , Mastócitos/metabolismo , Proteínas do Tecido Nervoso/química , Receptores Acoplados a Proteínas-G/química , Receptores de Neuropeptídeos/química , Substância P/metabolismo , Animais , Cálcio/metabolismo , Linhagem Celular Tumoral , Sequência Conservada , Humanos , Mutação de Sentido Incorreto , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Domínios Proteicos , Ratos , Receptores Acoplados a Proteínas-G/genética , Receptores Acoplados a Proteínas-G/metabolismo , Receptores de Neuropeptídeos/genética , Receptores de Neuropeptídeos/metabolismo
13.
J Dermatol Sci ; 95(3): 99-106, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31558225

RESUMO

BACKGROUND: Thimerosal has been used as a preservative in many products which may cause contact dermatitis. It is the second most common allergen in positive patch test reactions, though being a clinical irrelevant allergen. Thimerosal-induced contact dermatitis is generally considered to be a delayed-type hypersensitivity reaction, but it is difficult to explain the fact that most patients develop an allergic reaction upon first encounter with thimerosal. Recent studies have demonstrated the association between Mas-related G protein coupled receptor X2 (MRGPRX2) and pseudo-allergic reactions which occur at the first contact with stimulation. This suggests the possibility that thimerosal may cause contact dermatitis via MRGPRX2 mediated mechanism. OBJECTIVES: To investigate the role of Mas-related G-protein coupled receptor B2 (MrgprB2)/MRGPRX2 in contact dermatitis induced by thimerosal. METHODS: Thimerosal induced pseudo-allergic reactions via MrgprB2/ MRGPRX2 were investigated using a novel skin pseudo-allergic reaction mouse model, footpad swelling and extravasation assays in vivo and mast cell degranulation assay in vitro. RESULTS: Thimerosal induced contact dermatitis in dorsal skin and footpad swelling in wild-type mice, but had no significant effect in MrgprB2-knockout mice. Thimerosal-induced dermatitis is characterized by infiltration of inflammatory cells and elevation of serum histamine and inflammatory cytokines, rather than elevation of serum IgE level. Thimerosal increased the intracellular Ca2+ concentration in HEK293 cells overexpressing MrgprB2/MRGPRX2. Downregulation of MRGPRX2 resulted in the reduced degranulation of LAD2 human mast cells. CONCLUSIONS: MrgprB2 mediates thimerosal-induced mast cell degranulation and pseudo-allergic reaction in mice. MRGPRX2 may be a key contributor to human contact dermatitis.


Assuntos
Dermatite de Contato/etiologia , Hipersensibilidade Tardia/etiologia , Mastócitos/efeitos dos fármacos , Proteínas do Tecido Nervoso/metabolismo , Conservantes Farmacêuticos/toxicidade , Receptores Acoplados a Proteínas-G/metabolismo , Receptores de Neuropeptídeos/metabolismo , Timerosal/efeitos adversos , Administração Cutânea , Animais , Degranulação Celular/efeitos dos fármacos , Dermatite de Contato/patologia , Modelos Animais de Doenças , Células HEK293 , Humanos , Hipersensibilidade Tardia/patologia , Masculino , Mastócitos/patologia , Camundongos , Camundongos Knockout , Conservantes Farmacêuticos/administração & dosagem , Receptores Acoplados a Proteínas-G/genética , Timerosal/administração & dosagem
14.
Endocrinology ; 160(11): 2673-2691, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31436800

RESUMO

Isolated growth hormone deficiency type II (IGHD2) is mainly caused by heterozygous splice-site mutations in intron 3 of the GH1 gene. A dominant-negative effect of the mutant GH lacking exon 3 on wild-type GH secretion has been proposed; however, the molecular mechanisms involved are elusive. To uncover the molecular systems underlying GH deficiency in IGHD2, we established IGHD2 model mice, which carry both wild-type and mutant copies of the human GH1 gene, replacing each of the endogenous mouse Gh loci. Our IGHD2 model mice exhibited growth retardation along with intact cellular architecture and mildly activated endoplasmic reticulum stress in the pituitary gland, caused by decreased GH-releasing hormone receptor (Ghrhr) and Gh gene promoter activities. Decreased Ghrhr and Gh promoter activities were likely caused by reduced levels of nuclear CREB3L2, which was demonstrated to stimulate Ghrhr and Gh promoter activity. To our knowledge, this is the first in vivo study to reveal a novel molecular mechanism of GH deficiency in IGHD2, representing a new paradigm that differs from widely accepted models.


Assuntos
Nanismo Hipofisário/etiologia , Hormônio do Crescimento/metabolismo , Receptores de Neuropeptídeos/metabolismo , Receptores de Hormônios Reguladores de Hormônio Hipofisário/metabolismo , Animais , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Nanismo Hipofisário/patologia , Feminino , Hormônio do Crescimento/genética , Humanos , Masculino , Camundongos , Hipófise/metabolismo , Hipófise/ultraestrutura , Regiões Promotoras Genéticas , Receptores de Neuropeptídeos/genética , Receptores de Hormônios Reguladores de Hormônio Hipofisário/genética
15.
Acta Derm Venereol ; 99(12): 1131-1135, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31449313

RESUMO

Most canine visits to veterinarians are related to skin diseases with itch being the chief complaint. Historically, several itch-inducing molecules and pathways have been identified in mice, but whether or not these are similar in dogs is not yet known. Herein, we set out to study the expression of pruritogenic neuropeptides, their cognate receptors with a limited functional validation thereof using a multidisciplinary approach. We demonstrated the expression of somatostatin and other major neuropeptides and receptors in canine dorsal root ganglia neurons. Next, we showed that interleukin-31, serotonin, and histamine activate such neurons. Furthermore, we demonstrated the physiological release of somatostatin from dog dorsal root ganglia neurons in response to several endogenous itch mediators. In summary, our results provide the first evidence that dogs use similar pruritogenic pathways to those characterized in mice and we thus identify multiple targets for the future treatment of itch in dogs.


Assuntos
Gânglios Espinais/metabolismo , Neuropeptídeos/metabolismo , Prurido/metabolismo , Receptores de Neuropeptídeos/metabolismo , Medula Espinal/metabolismo , Animais , Sinalização do Cálcio , Células Cultivadas , Cães , Feminino , Gânglios Espinais/fisiopatologia , Regulação da Expressão Gênica , Masculino , Neuropeptídeos/genética , Prurido/genética , Prurido/fisiopatologia , Receptores de Neuropeptídeos/genética , Medula Espinal/fisiopatologia
16.
Cell Host Microbe ; 26(1): 114-122.e8, 2019 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-31278040

RESUMO

Quorum-sensing molecules (QSMs) are secreted by bacteria to signal population density. Upon reaching a critical concentration, QSMs induce transcriptional alterations in bacteria, which enable virulence factor expression and biofilm formation. It is unclear whether mammalian hosts can recognize QSMs to trigger responsive antibacterial immunity. We report that mouse mast-cell-specific G-protein-coupled receptor Mrgprb2 and its human homolog MRGPRX2 are receptors for Gram-positive QSMs, including competence-stimulating peptide (CSP)-1. CSP-1 activates Mrgprb2 and MRGPRX2, triggering mast cell degranulation, which inhibits bacterial growth and prevents biofilm formation. Such antibacterial functions are reduced in Mrgprb2-deficient mast cells, while wild-type mast cells fail to inhibit the growth of bacterial strains lacking CSP-1. Mrgprb2-knockout mice exhibit reduced bacterial clearance, while pharmacologically activating Mrgprb2 in vivo eliminates bacteria and improves disease score. These findings identify a host defense mechanism that uses QSMs as an "Achilles heel" and suggest MRGPRX2 as a potential therapeutic target for controlling bacterial infections.


Assuntos
Proteínas de Bactérias/metabolismo , Tecido Conjuntivo/imunologia , Imunidade Inata , Mastócitos/imunologia , Proteínas do Tecido Nervoso/metabolismo , Receptores Acoplados a Proteínas-G/metabolismo , Receptores de Neuropeptídeos/metabolismo , Streptococcus pneumoniae/imunologia , Animais , Bacteriocinas/metabolismo , Enterococcus faecium/imunologia , Humanos , Camundongos , Camundongos Knockout , Streptococcus pyogenes/imunologia
18.
Mol Med Rep ; 20(2): 2030-2038, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31257494

RESUMO

Neuropeptide B (NPB) regulates food intake, body weight and energy homeostasis by interacting with NPBW1/NPBW2 in humans and NPBW1 in rodents. NPB and NPBW1 are widely expressed in the central nervous system and peripheral tissues including pancreatic islets. Although previous studies have demonstrated a prominent role for NPB and NPBW1 in controlling glucose and energy homeostasis, it remains unknown as to whether NPB modulates pancreatic ß­cell functions. Therefore, the aim of the present study was to investigate the effects of NPB on insulin expression and secretion in vitro. Furthermore, the role of NPB in the modulation of INS­1E cell growth, viability and death was examined. Gene expression was assessed by reverse transcription­quantitative PCR. Cell proliferation and viability were determined by BrdU or MTT tests, respectively. Apoptotic cell death was evaluated by relative quantification histone­complexed DNA fragments (mono­and oligonucleosomes). Insulin secretion was studied using an ELISA test. Protein phosphorylation was assessed by western blot analysis. NPB and NPBW1 mRNA was expressed in INS­1E cells and rat pancreatic islets. In INS­1E cells, NPB enhanced insulin 1 mRNA expression via an ERK1/2­dependent mechanism. Furthermore, NPB stimulated insulin secretion from INS­1E cells and rat pancreatic islets. By contrast, NPB failed to affect INS­1E cell growth or death. We conclude that NPB may regulate insulin secretion and expression in INS­1E cells and insulin secretion in rat pancreatic islets.


Assuntos
Células Secretoras de Insulina/metabolismo , Insulina/biossíntese , Neuropeptídeos/genética , Receptores de Neuropeptídeos/genética , Animais , Proliferação de Células/genética , Glucose/metabolismo , Humanos , Insulina/genética , Secreção de Insulina/genética , Células Secretoras de Insulina/patologia , Ilhotas Pancreáticas/metabolismo , Neuropeptídeos/metabolismo , Fosforilação , RNA Mensageiro/genética , Ratos
19.
J Dairy Res ; 86(3): 331-336, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31288873

RESUMO

We investigated whether variation of the sheep Growth Hormone Receptor (GHR), Growth Hormone Releasing Hormone Receptor (GHRHR) and Insulin-Like Growth Factor 1 (IGF1) genes were associated with milk coagulation properties (MCP) in sheep. The GHR, GHRHR and IGF1 genes are part of the GH system, which is known to modulate metabolism, growth and reproduction as well as mammogenesis and galactopoiesis in dairy species. A total of 380 dairy Sarda sheep were genotyped for 36 SNPs mapping to these three genes. Traditional MCP were measured as rennet coagulation time (RCT), curd-firming time (k20) and curd firmness at 30 m (a30). Modeling of curd firming over time (CFt) was based on a 60 m lactodynamographic test, generating a total of 240 records of curd firmness (mm) for each milk sample. The model parameters obtained included: the rennet coagulation time as a result of modeling all data available (RCTeq, min); the asymptotic potential value of curd firmness (CFP, mm) at an infinite time; the CF instant rate constant (kCF, %/min); the syneresis instant rate constant (kSR, %/min); the maximum value of CF (CFmax, mm) and the time at achievement of CFmax (tmax, min). Statistical analysis revealed that variation of the GHR gene was significantly associated with RCT, kSR and CFP (P < 0.05). No other significant associations were detected. These findings may be useful for the dairy industry, as well as for selection programs.


Assuntos
Fator de Crescimento Insulin-Like I/genética , Leite/fisiologia , Polimorfismo de Nucleotídeo Único/genética , Receptores de Neuropeptídeos/genética , Receptores de Hormônios Reguladores de Hormônio Hipofisário/genética , Receptores da Somatotropina/genética , Ovinos/genética , Animais , Quimosina/metabolismo , Feminino , Genótipo , Itália , Lactação/genética , Leite/química , Especificidade da Espécie
20.
Chin J Physiol ; 62(2): 47-52, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31243174

RESUMO

Neuropeptide FF (NPFF) is known as a morphine-modulating peptide and was first isolated in 1985. It has been characterized as an RF-amide peptide. The traditional role of NPFF is mediation of the pain response, and it displays both anti-opioid and pro-opioid actions through central nervous system. In the recent decade, additional evidence has revealed some untraditional features of NPFF, such as regulation of the neuroendocrine system, energy homeostasis, anti-inflammation, pain transmission, and peripheral modulation of adipose tissue macrophages. Neuropeptide FF receptor 2 (NPFFR2) is a physiological receptor of NPFF, and the actions of NPFF may occur through downstream NPFFR2 signaling. NPFF and NPFFR2 increase the neuronal activity in various areas of the hypothalamus to modulate the hypothalamic-pituitary-adrenal axis, the autonomic nervous system, food intake, and energy balance. These underlying cellular mechanisms have been explored in the past few years. Here, we review the impact of NPFF and related RF-amide peptides on hypothalamic function. The interaction of NPFF with NPFFR2 in the hypothalamus is emphasized, and NPFF-NPFFR2 system may represent an important therapeutic target in hypothalamic-related disorders in the future.


Assuntos
Homeostase , Sistema Hipotálamo-Hipofisário , Hipotálamo , Sistemas Neurossecretores , Oligopeptídeos , Sistema Hipófise-Suprarrenal , Receptores de Neuropeptídeos
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