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1.
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
2.
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
3.
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
4.
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
5.
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
6.
Med Hypotheses ; 128: 54-57, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31203909

RESUMO

Hypogonadotropic hypogonadism (secondary hypogonadism), congenital or acquired, is a form of hypogonadism that is due to problems with either the hypothalamus or pituitary gland affecting gonadotropin levels. Pulsatile secretion of gonadotropin-releasing hormone (GnRH) by hypothalamus is a primer step to initiate the release of pituitary gonadotropins. Kisspeptin and gonadotropin-inhibitory hormone (GnIH) are accepted as two major players in the activation and inhibition of GnRH regarding the neuroendocrine functioning of the hypothalamic pituitary gonadal axis. Kisspeptin is known as the most potent activator of GnRH. Regarding the inhibition of GnRH, RF-amide-related peptide-3 (RFRP-3) is accepted as the mammalian orthologue of GnIH in avian species. RF9 (1-adamantane carbonyl-Arg-Phe-NH2) is an antagonist of RFRP-3/GnIH receptor (neuropeptide FF receptor 1 (NPFFR1; also termed as GPR147). In recent years, several studies have indicated that RF9 activates GnRH neurons and gonadotropins in a kisspeptin receptor (Kiss1r, formerly known as GPR54) dependent manner. These results suggest that RF9 may have a bimodal function as both an RFRP-3 antagonist and a kisspeptin agonist or it may be a kiss1r agonist rather than an RFRP-3/GnIH receptor antagonist. These interactions are possible because Kisspeptin and GnIH are members of the RF-amide family, and both possibilities are not far from explaining the potent gonadotropin stimulating effects of RF9. Therefore, we hypothesize that RF9 may be a new therapeutic option for the hypogonadotropic hypogonadism due to its potent GnRH stimulating effects. A constant or repeated administration of RF9 provides a sustained increase in plasma gonadotrophin levels. However, applications in the same way with GnRH analogues and kisspeptin may result in desensitization of the gonadotropic axis. The reasons reported above contribute to our hypothesis that RF9 may be a good option in the GnRH stimulating as a kisspeptin agonist. We suggest that further studies are needed to elucidate the potential effects of RF9 in the treatment of the hypogonadotropic hypogonadism.


Assuntos
Adamantano/análogos & derivados , Dipeptídeos/farmacologia , Hormônio Liberador de Gonadotropina/metabolismo , Gonadotropinas/metabolismo , Hipogonadismo/metabolismo , Hipotálamo/metabolismo , Adamantano/farmacologia , Animais , Células CHO , Cricetinae , Cricetulus , Humanos , Hipogonadismo/terapia , Camundongos , Modelos Biológicos , Modelos Teóricos , Neuropeptídeos/metabolismo , Ratos , Receptores de Kisspeptina-1/metabolismo , Receptores de Neuropeptídeos/metabolismo
7.
Int J Mol Sci ; 20(12)2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31216652

RESUMO

The sharing of molecules function that affects both tumor growth and neoangiogenesis with cells of the immune system creates a mutual interplay that impairs the host's immune response against tumor progression. Increasing evidence shows that tumors are able to create an immunosuppressive microenvironment by recruiting specific immune cells. Moreover, molecules produced by tumor and inflammatory cells in the tumor microenvironment create an immunosuppressive milieu able to inhibit the development of an efficient immune response against cancer cells and thus fostering tumor growth and progression. In addition, the immunoediting could select cancer cells that are less immunogenic or more resistant to lysis. In this review, we summarize recent findings regarding the immunomodulatory effects and cancer progression of the angiogenic growth factor namely placental growth factor (PlGF) and address the biological complex effects of this cytokine. Different pathways of the innate and adaptive immune response in which, directly or indirectly, PlGF is involved in promoting tumor immune escape and metastasis will be described. PlGF is important for building up vascular structures and functions. Although PlGF effects on vascular and tumor growth have been widely summarized, its functions in modulating the immune intra-tumoral microenvironment have been less highlighted. In agreement with PlGF functions, different antitumor strategies can be envisioned.


Assuntos
Vigilância Imunológica , Neoplasias/etiologia , Neoplasias/metabolismo , Fator de Crescimento Placentário/genética , Fator de Crescimento Placentário/metabolismo , Indutores da Angiogênese/metabolismo , Animais , Progressão da Doença , Avaliação Pré-Clínica de Medicamentos , Humanos , Imunomodulação , Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Neovascularização Patológica/genética , Neovascularização Patológica/imunologia , Neovascularização Patológica/metabolismo , Receptores de Neuropeptídeos/metabolismo , Transdução de Sinais
8.
J Insect Sci ; 19(2)2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31222323

RESUMO

Pheromonal communication is important in insect mate finding and reproduction. Identifying components of pest insect pheromone system is a first step to disrupt pest insect reproduction. In this study, we identified and cloned the pheromone biosynthesis activating neuropeptide receptor (PBANR) from the Asian corn borer, Ostrinia furnacalis (Guenée) (Lepidoptera: Pyralidae), which is one of the most damaging pests of corn and other crops in parts of Asia and Australia. The O. furnacalis PBANR (OstfuPBANR) gene has an ORF of 1,086 bp and encoded 362 amino acids with seven transmembrane domains and had a high sequence identity to known lepidopteran PBANRs. Expression analysis showed that OstfuPBANR was highly expressed in the pheromone glands compared with other tissues, consistent with other studies. Interestingly, OstfuPBANR was expressed higher in the larval stages compared to the pupal or adult stages, suggesting that OstfuPBANR may have broad functions in larva beyond adult pheromone synthesis.


Assuntos
Mariposas/metabolismo , Receptores de Neuropeptídeos/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Feminino , Expressão Gênica , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Mariposas/genética , Feromônios/biossíntese , Receptores de Neuropeptídeos/genética , Análise de Sequência de DNA
9.
Endocrinology ; 160(7): 1600-1612, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31070727

RESUMO

In this article, we briefly review the identification of GHRH, provide an abridged overview of GHRH antagonists, and focus on studies with GHRH agonists. Potent GHRH agonists of JI and MR class were synthesized and evaluated biologically. Besides the induction of the release of pituitary GH, GHRH analogs promote cell proliferation and exert stimulatory effects on various tissues, which express GHRH receptors (GHRH-Rs). A large body of work shows that GHRH agonists, such as MR-409, improve pancreatic ß-cell proliferation and metabolic functions and facilitate engraftment of islets after transplantation in rodents. Accordingly, GHRH agonists offer a new therapeutic approach to treating diabetes. Various studies demonstrate that GHRH agonists promote repair of cardiac tissue, producing improvement of ejection fraction and reduction of infarct size in rats, reduction of infarct scar in swine, and attenuation of cardiac hypertrophy in mice, suggesting clinical applications. The presence of GHRH-Rs in ocular tissues and neuroprotective effects of GHRH analogs in experimental diabetic retinopathy indicates their possible therapeutic applications for eye diseases. Other effects of GHRH agonists, include acceleration of wound healing, activation of immune cells, and action on the central nervous system. As GHRH might function as a growth factor, we examined effects of GHRH agonists on tumors. In vitro, GHRH agonists stimulate growth of human cancer cells and upregulate GHRH-Rs. However, in vivo, GHRH agonists inhibit growth of human cancers xenografted into nude mice and downregulate pituitary and tumoral GHRH-Rs. Therapeutic applications of GHRH analogs are discussed. The development of GHRH analogs should lead to their clinical use.


Assuntos
Diabetes Mellitus/tratamento farmacológico , Hormônio Liberador de Hormônio do Crescimento/metabolismo , Neoplasias/tratamento farmacológico , Receptores de Neuropeptídeos/agonistas , Receptores de Hormônios Reguladores de Hormônio Hipofisário/agonistas , Animais , Linhagem Celular Tumoral , Humanos , Receptores de Neuropeptídeos/metabolismo , Receptores de Hormônios Reguladores de Hormônio Hipofisário/metabolismo
10.
Acta Biochim Biophys Sin (Shanghai) ; 51(6): 627-637, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31056648

RESUMO

Class B G-protein coupled receptors (GPCR) PAC1-R is a neuropeptide pituitary adenylate cyclase activating polypeptide (PACAP)-preferring receptor that mediates the effective neuroprotective activity. Based on our previous data showing that doxycycline and minocycline work as the positive allosteric modulator (PAM) of PAC1-R, we used computer molecular docking and isothermal titration calorimetry assay to further determine the bindings of doxycycline/minocycline's derivatives including tetracycline/tigecycline with the N-terminal extracellular domain of PAC1-R (PAC1-EC1). Then the cAMP assay combined with the PAC1-R natural agonist PACAP27 was used to confirm the possible PAM roles of the small-molecule antibiotics. The results showed that tetracycline/tigecycline had significant lower affinity to PAC1-EC1 than doxycycline/minocycline, which was consistent with their non-positive allosteric modulation activity on PAC1-R. Furthermore, by comparing the key residues contributing to the PAM binding with the predicted allosteric site in PAC1-EC1, we characterized four motifs contributing to PAM binding in PAC1-EC1. The site-directed mutation results showed that ASN60 played the most important role in the PAM binding of the small-molecule antibiotics, while ASP116 played a sensitive marginal role in the PAM binding. These results not only help to explain the clinical and experimental neuroprotective effects of doxycycline/minocycline, but also help to characterize the PAM binding site in PAC1-EC1, which will promote the screening and characterization of novel small-molecule PAMs targeting PAC1-EC1 with drug development potency in nerve system disease.


Assuntos
Doxiciclina/metabolismo , Minociclina/metabolismo , Simulação de Acoplamento Molecular , Receptores de Neuropeptídeos/metabolismo , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Sequência de Aminoácidos , Animais , Antibacterianos/química , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Sítios de Ligação/genética , Células CHO , Cricetinae , Cricetulus , Doxiciclina/química , Doxiciclina/farmacologia , Humanos , Minociclina/química , Minociclina/farmacologia , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/metabolismo , Fármacos Neuroprotetores/farmacologia , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/farmacologia , Ligação Proteica/efeitos dos fármacos , Receptores de Neuropeptídeos/química , Receptores de Neuropeptídeos/genética , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/agonistas , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/química , Homologia de Sequência de Aminoácidos
11.
Contact Dermatitis ; 81(3): 184-193, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31006867

RESUMO

BACKGROUND: Retinoic acid (RA)-induced dermatitis is the most frequent side-effect limiting its widespread use. However, the exact mechanisms triggering dermatitis are not fully understood, including the role of skin mast cells. The newly discovered Mas-related G-protein-coupled receptor-X2 (MRGPRX2) in mast cells mediates pseudoallergic drug reactions in several types of dermatitis. A possible contribution of MRGPRX2 to contact dermatitis induced by RA has hitherto not been examined. OBJECTIVES: To investigate whether all-trans-RA (ATRA) activates mast cells via MRGPRX2/MrgprB2 (the mouse orthologue), contributing to the pathogenesis of retinoid-induced dermatitis. METHODS: Wild-type (WT) and MrgprB2-/- mice were treated with topical ATRA to observe local inflammation and mast cell degranulation in vivo by the use of haematoxylin and eosin and immunofluorescence staining. Release of histamine and release of ß-hexosaminidase were measured and calcium influx was detected in Laboratory of Allergic Disease 2 (LAD2) cells with specific knockdown targeting MRGPRX2 by small interfering RNA (siRNA) and in primary cells from MrgprB2-/- mice. RESULTS: As compared with WT mice, MrgprB2-/- mice showed resistance to ATRA-triggered contact dermatitis and local inflammatory reactions in the paws. ATRA activated mast cells via the MrgprB2 pathway in murine cells, and via the MRGPRX2 pathway in human mast cells. CONCLUSIONS: ATRA-induced dermatitis could be achieved by activating mast cells via MRGPRX2/MrgprB2, which may provide a potential therapy target to reduce the side-effect.


Assuntos
Degranulação Celular/efeitos dos fármacos , Dermatite de Contato/etiologia , Mastócitos/fisiologia , Receptores Acoplados a Proteínas-G/genética , Tretinoína/farmacologia , Animais , Cálcio/metabolismo , Linhagem Celular , Dermatite , Dermatite de Contato/genética , Técnicas de Silenciamento de Genes , Histamina/metabolismo , Humanos , Masculino , Mastócitos/metabolismo , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Receptores Acoplados a Proteínas-G/metabolismo , Receptores de Neuropeptídeos/metabolismo , Tretinoína/toxicidade , beta-N-Acetil-Hexosaminidases/metabolismo
12.
Reprod Domest Anim ; 54(6): 892-901, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31002198

RESUMO

The aim of this research was to investigate the changes in reproductive hormone receptor expressions of the ovary and hormone concentrations between oestrous cycle pattern of two different sheep breeds in China. Ovarian tissues were collected from Chinese Merino (Junken type) and Hu sheep with different reproductive states in spring and autumn. Serum samples were assayed for oestrogen (E2), progesterone (P), luteinizing hormone (LH) and follicle-stimulating hormone (FSH) concentrations by radioimmunoassay during spring. The ovarian expression of hormone receptors (ERα, ERß, PR, LHR and FSHR) was analysed using real-time reverse transcription polymerase chain reaction (RT-PCR). In Chinese Merino, there was no corpora lutea and ovulation point on the surfaces of ovaries in spring and low basal levels of both LH and P in serum. ERα, ERß and FSHR were expressed significantly higher in Merino ovaries during anoestrus compared with oestrous or luteal phases of Hu sheep (p < 0.05 or p < 0.01). However, both varieties of sheep exhibited a similar tendency to secrete E2 and FSH. Compared with Hu sheep, FSH levels were slightly higher in Merino serum. In Hu sheep, ERα, ERß, FSHR, LHR and PR expressed in luteal phase ovaries during spring were significantly lower (p < 0.05, p < 0.01 or p < 0.001) than autumn. Interestingly, LHR and PR expressed in anoestrous ovaries were similar to that in oestrous phase of both sheep breeds. The above results suggest that seasonal reproductive sheep increased the expression of E2 and FSH receptors in ovary during spring may enhance the effects of E2 and FSH on follicular development. It is likely that this enhancement prevents the ovary from progressing to the luteal phase.


Assuntos
Ciclo Estral/fisiologia , Ovário/fisiologia , Estações do Ano , Carneiro Doméstico/fisiologia , Animais , Estrogênios/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Regulação da Expressão Gênica , Hormônio Luteinizante/sangue , Progesterona/sangue , Receptores de Neuropeptídeos/metabolismo , Receptores de Esteroides/metabolismo , Especificidade da Espécie
13.
Int J Mol Sci ; 20(7)2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30934667

RESUMO

Gastrointestinal motility is regulated by neural factors and humoral factors. Both motilin and ghrelin improve gastrointestinal motility, but many issues remain unclear. We prepared human motilin receptor transgenic (Tg) mice and performed experiments evaluating the effects of motilin, erythromycin (EM), and ghrelin. EM and ghrelin promoted gastric emptying (GE) when administered either peripherally or centrally to Tg mice. Atropine (a muscarinic receptor antagonist) counteracted GE induced by centrally administered EM, but not that induced by peripherally administered EM. The administration of EM in this model promoted the effect of mosapride (a selective serotonin 5-hydroxytryptamine 4 (5-HT4) receptor agonist), and improved loperamide (a µ-opioid receptor agonist)-induced gastroparesis. The level of acyl-ghrelin was significantly attenuated by EM administration. Thus, we have established an animal model appropriate for the evaluation of motilin receptor agonists. These data and the model are expected to facilitate the identification of novel compounds with clinical potential for relieving symptoms of dyspepsia and gastroparesis.


Assuntos
Grelina/farmacologia , Receptores dos Hormônios Gastrointestinais/agonistas , Receptores de Neuropeptídeos/agonistas , Animais , Benzamidas/farmacologia , Eritromicina/administração & dosagem , Eritromicina/farmacologia , Esvaziamento Gástrico/efeitos dos fármacos , Gastroparesia/sangue , Gastroparesia/induzido quimicamente , Gastroparesia/tratamento farmacológico , Gastroparesia/fisiopatologia , Grelina/sangue , Humanos , Loperamida/efeitos adversos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Morfolinas/farmacologia , Período Pós-Prandial , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores dos Hormônios Gastrointestinais/genética , Receptores dos Hormônios Gastrointestinais/metabolismo , Receptores de Grelina/genética , Receptores de Grelina/metabolismo , Receptores de Neuropeptídeos/genética , Receptores de Neuropeptídeos/metabolismo , Estômago/efeitos dos fármacos , Estômago/patologia , Estômago/fisiopatologia , Nervo Vago/efeitos dos fármacos , Nervo Vago/fisiologia
14.
Cells ; 8(4)2019 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-30979016

RESUMO

Clinically relevant exocytosis of mast cell (MC) mediators can be triggered by high-affinity IgE receptor (FcεRI)-aggregation (allergic route) or by the so-called pseudo-allergic pathway elicited via MAS-related G protein-coupled receptor-X2 (MRGPRX2). The latter is activated by drugs and endogenous neuropeptides. We recently reported that FcεRI-triggered degranulation is attenuated when human skin mast cells are chronically exposed to IL-33. Here, we were interested in the regulation of the MRGPRX2-route. Chronic exposure of skin MCs to IL-33 basically eliminated the pseudo-allergic/neurogenic route as a result of massive MRGPRX2 reduction. This downregulation seemed to partially require c-Jun N-terminal Kinase (JNK), but not p38, the two kinases activated by IL-33 in skin MCs. Surprisingly, however, JNK had a positive effect on MRGPRX2 expression in the absence of IL-33. This was evidenced by Accell®-mediated JNK knockdown and JNK inhibition. In stark contrast to the dampening effect upon prolonged exposure, IL-33 was able to prime for increased degranulation by MRGPRX2 ligands when administered directly before stimulation. This supportive effect depended on p38, but not on JNK activity. Our data reinforce the concept that exposure length dictates whether IL-33 will enhance or attenuate secretion. IL-33 is, thus, the first factor to acutely enhance MRGPRX2-triggered degranulation. Finally, we reveal that p38, rarely associated with MC degranulation, can positively affect exocytosis in a context-dependent manner.


Assuntos
Degranulação Celular , Interleucina-33/fisiologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Mastócitos/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Receptores Acoplados a Proteínas-G/metabolismo , Receptores de Neuropeptídeos/metabolismo , Pele/imunologia , Células Cultivadas , Humanos , Interleucina-33/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Mastócitos/citologia , Pele/citologia
15.
Cells ; 8(4)2019 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-30987258

RESUMO

Host-defense peptides (HDPs) have an important therapeutic potential against microbial infections but their metabolic instability and cellular cytotoxicity have limited their utility. To overcome these limitations, we utilized five small-molecule, nonpeptide HDP mimetics (smHDPMs) and tested their effects on cytotoxicity, antimicrobial activity, and mast cell (MC) degranulation. None of the smHDPMs displayed cytotoxicity against mouse 3T3 fibroblasts or human transformed liver HepG2 cells. However, one compound had both antifungal and antibacterial activity. Surprisingly, all five compounds induced degranulation in a human MC line, LAD2, and this response was substantially reduced in Mas-related G protein-coupled receptor (GPCR)-X2 (MRGPRX2)-silenced cells. Furthermore, all five compounds induced degranulation in RBL-2H3 cells expressing MRGPRX2 but this response was abolished in cells expressing naturally occurring loss-of-function missense variants G165E (rs141744602) and D184H (rs372988289). Mrgprb2 is the likely mouse ortholog of human MRGPRX2, which is expressed in connective tissue MCs (CTMCs) such as cutaneous and peritoneal MCs (PMCs). All five smHDPMs induced degranulation in wild-type PMCs but not in cells derived from Mrgprb2⁻/⁻ mice. These findings suggest that smHDPMs could serve as novel targets for the treatment of drug-resistant fungal and bacterial infections because of their ability to harness CTMCs' host defense functions.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Mastócitos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Peptídeos/farmacologia , Receptores Acoplados a Proteínas-G/metabolismo , Receptores de Neuropeptídeos/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Células 3T3 , Animais , Antibacterianos/química , Antifúngicos/química , Degranulação Celular/efeitos dos fármacos , Fungos/efeitos dos fármacos , Células Hep G2 , Humanos , Mastócitos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Testes de Sensibilidade Microbiana , Mutação de Sentido Incorreto/genética , Ratos
16.
Immunity ; 50(5): 1163-1171.e5, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31027996

RESUMO

Classical itch studies have focused on immunoglobulin E (IgE)-mediated mast cell activation and histamine release. Recently, members of the Mas-related G-protein-coupled receptor (Mrgpr) family have been identified as mast cell receptors, but their role in itch is unclear. Here, we report that mast cell activation via Mrgprb2 evoked non-histaminergic itch in mice independently of the IgE-Fc epsilon RI (FcεRI)-histamine axis. Compared with IgE-FcεRI stimulation, Mrgprb2 activation of mast cells was distinct in both released substances (histamine, serotonin, and tryptase) and the pattern of activated itch-sensory neurons. Mrgprb2 deficiency decreased itch in multiple preclinical models of allergic contact dermatitis (ACD), a pruritic inflammatory skin disorder, and both mast cell number and PAMP1-20 concentrations (agonist of the human Mrgprb2 homolog, MRGPRX2) were increased in human ACD skin. These findings suggest that this pathway may represent a therapeutic target for treating ACD and mast-cell-associated itch disorders in which antihistamines are ineffective.


Assuntos
Mastócitos/imunologia , Proteínas do Tecido Nervoso/metabolismo , Prurido/patologia , Receptores Acoplados a Proteínas-G/metabolismo , Receptores de IgE/metabolismo , Receptores de Neuropeptídeos/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Feminino , Histamina/metabolismo , Antagonistas dos Receptores Histamínicos/uso terapêutico , Humanos , Imunoglobulina E/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Fragmentos de Peptídeos/metabolismo , Receptores Acoplados a Proteínas-G/genética , Serotonina/metabolismo , Pele/metabolismo , Triptases/metabolismo , Adulto Jovem
17.
Int Immunopharmacol ; 70: 417-427, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30856392

RESUMO

Fluoroquinolones trigger anaphylaxis during clinical applications, affecting the safety of their administration. Mast cells are immune cells that act as sentinels during host defenses, mediating hypersensitivity and anaphylactic reactions. Mas-related G protein-coupled receptor X2 (MRGPRX2) is a mast cell-specific receptor that mediates cell degranulation in anaphylactic reactions. In this study, the mechanism underpinning the anaphylactic reactions caused by fluoroquinolones was investigated. Hypersensitivity was assessed through hindpaw swelling, tissue fluid leakage assays, in vivo and body temperature measurements assay in vivo, and cell calcium mobilization assays, and mast cell degranulation assays in vitro. Mast cell-deficient W-sash c-kit mutant KitW-sh/W-sh mice and MrgprB2 (the orthologous receptor of MRGPRX2 in mice) knockout mice exhibited reduced fluoroquinolone-induced anaphylactic effects. Fluoroquinolones activated mast cells in a dose-dependent manner and reduced degranulation was observed following MRGPRX2 silencing. These results reveal that fluoroquinolone-induced anaphylactic reactions are mediated by mast cells through MRGPRX2.


Assuntos
Anafilaxia/metabolismo , Fluoroquinolonas/metabolismo , Hipersensibilidade/metabolismo , Mastócitos/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Receptores Acoplados a Proteínas-G/metabolismo , Receptores de Neuropeptídeos/metabolismo , Anafilaxia/induzido quimicamente , Anafilaxia/genética , Animais , Temperatura Corporal , Sinalização do Cálcio , Degranulação Celular/genética , Permeabilidade da Membrana Celular/genética , Fluoroquinolonas/química , Células HEK293 , Humanos , Hipersensibilidade/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Mutantes , Proteínas do Tecido Nervoso/genética , RNA Interferente Pequeno/genética , Receptores Acoplados a Proteínas-G/genética , Receptores de Neuropeptídeos/genética
18.
PLoS One ; 14(2): e0205939, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30789939

RESUMO

Motilin is a gastrointestinal peptide hormone that stimulates gastrointestinal motility. Motilin is produced primarily in the duodenum and jejunum. Motilin receptors (MTLRs) are G protein-coupled receptors that may represent a clinically useful pharmacological target as they can be activated by erythromycin. The functions of motilin are highly species-dependent and remain poorly understood. As a functional motilin system is absent in rodents such as rats and mice, these species are not commonly used for basic studies. In this study, we examine the usefulness of human MTLR-overexpressing transgenic (hMTLR-Tg) mice by identifying the mechanisms of the gastric motor response to human motilin and erythromycin. The distribution of hMTLR was examined immunohistochemically in male wild-type (WT) and hMTLR-Tg mice. The contractile response of gastric strips was measured isometrically in an organ bath, while gastric emptying was determined using phenol red. hMTLR expression was abundant in the gastric smooth muscle layer. Interestingly, higher levels of hMTLR expression were observed in the myenteric plexus of hMTLR-Tg mice but not WT mice. hMTLR was not co-localized with vesicular acetylcholine transporter, a marker of cholinergic neurons in the myenteric plexus. Treatment with human motilin and erythromycin caused concentration-dependent contraction of gastric strips obtained from hMTLR-Tg mice but not from WT mice. The contractile response to human motilin and erythromycin in hMTLR-Tg mice was affected by neither atropine nor tetrodotoxin and was totally absent in Ca2+-free conditions. Furthermore, intraperitoneal injection of erythromycin significantly promoted gastric emptying in hMTLR-Tg mice but not in WT mice. Human motilin and erythromycin stimulate gastric smooth muscle contraction in hMTLR-Tg mice. This action is mediated by direct contraction of smooth muscle via the influx of extracellular Ca2+. Thus, hMTLR-Tg mice may be useful for the evaluation of MTLR agonists as gastric prokinetic agents.


Assuntos
Eritromicina/metabolismo , Motilidade Gastrointestinal/fisiologia , Motilina/metabolismo , Receptores dos Hormônios Gastrointestinais/metabolismo , Receptores de Neuropeptídeos/metabolismo , Animais , Cálcio/metabolismo , Cátions Bivalentes/metabolismo , Neurônios Colinérgicos/citologia , Neurônios Colinérgicos/metabolismo , Expressão Gênica , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Contração Muscular/fisiologia , Músculo Liso/citologia , Músculo Liso/metabolismo , Plexo Mientérico/citologia , Plexo Mientérico/metabolismo , Receptores dos Hormônios Gastrointestinais/genética , Receptores de Neuropeptídeos/genética , Estômago/citologia , Estômago/fisiologia , Técnicas de Cultura de Tecidos
19.
Pest Manag Sci ; 75(6): 1750-1759, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30734498

RESUMO

BACKGROUND: Neuropeptides are regulators of critical life processes in insects and, due to their high specificity, represent potential targets in the development of greener insecticidal agents. Fundamental to this drive is understanding neuroendocrine pathways that control key physiological processes in pest insects and the screening of potential analogues. The current study investigated neuropeptide binding sites of kinin and CAPA (CAPA-1) in the aphids Myzus persicae and Macrosiphum rosae and the effect of biostable analogues on aphid fitness under conditions of desiccation, starvation and thermal (cold) stress. RESULTS: M. persicae and M. rosae displayed identical patterns of neuropeptide receptor mapping along the gut, with the gut musculature representing the main target for kinin and CAPA-1 action. While kinin receptor binding was observed in the brain and VNC of M. persicae, this was not observed in M. rosae. Furthermore, no CAPA-1 receptor binding was observed in the brain and VNC of either species. CAP2b/PK analogues (with CAPA receptor cross-activity) were most effective in reducing aphid fitness under conditions of desiccation and starvation stress, particularly analogues 1895 (2Abf-Suc-FGPRLa) and 2129 (2Abf-Suc-ATPRIa), which expedited aphid mortality. All analogues, with the exception of 2139-Ac, were efficient at reducing aphid survival under cold stress, although were equivalent in the strength of their effect. CONCLUSION: In demonstrating the effects of analogues belonging to the CAP2b neuropeptide family and key analogue structures that reduce aphid fitness under stress conditions, this research will feed into the development of second generation analogues and ultimately the development of neuropeptidomimetic-based insecticidal agents. © 2019 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Afídeos/efeitos dos fármacos , Afídeos/fisiologia , Cininas/química , Cininas/farmacologia , Neuropeptídeos/química , Neuropeptídeos/farmacologia , Oligopeptídeos/química , Oligopeptídeos/farmacologia , Ácido Pirrolidonocarboxílico/análogos & derivados , Estresse Fisiológico/efeitos dos fármacos , Animais , Sítios de Ligação , Resposta ao Choque Térmico/efeitos dos fármacos , Cininas/metabolismo , Neuropeptídeos/metabolismo , Oligopeptídeos/metabolismo , Ácido Pirrolidonocarboxílico/química , Ácido Pirrolidonocarboxílico/metabolismo , Ácido Pirrolidonocarboxílico/farmacologia , Receptores de Neuropeptídeos/metabolismo
20.
Gen Comp Endocrinol ; 277: 38-48, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30771290

RESUMO

Motilin (MLN), an interdigestive hormone secreted by endocrine cells of the intestinal mucosa, binds to a G protein-coupled receptor to exert its biological function of regulating gastrointestinal motility. In the present study, we identified the prepromotilin and mln receptor (mlnr) from the spotted sea bass, Lateolabrax maculatus. Mln consisted of an ORF of 336 nucleotides encoding 111 amino acids. The precursor protein contained a 17-amino-acid mature peptide. Mlnr had an ORF of 1089 bp encoding a protein of 362 amino acids. Seven transmembrane domains were predicted with TMHMM analysis. The phylogenetic analysis of mln and mlnr showed that they fell into the same clade with respective counterpart of selected fishes before clustering with other detected vertebrates. Both mln and mlnr genes were highly expressed in intestine of spotted sea bass using quantitative real-time PCR. In situ hybridization indicated that mln and mlnr mRNA were both localized in the lamina propria and the epithelial cell of intestinal villus. The expressions of both genes were regulated under short-term starvation in a time-dependent manner. In vitro experiments indicated that the expressions of ghrelin (ghrl), gastrin (gas) and cholecystokinin (cck) were enhanced by MLN after 3-h treatment, but the effect was absent after 6 or 12-h incubation. Taken together, the MLN and its receptor might play important roles in regulating intestinal motility in spotted sea bass.


Assuntos
Bass/genética , Perfilação da Expressão Gênica , Motilina/genética , Receptores dos Hormônios Gastrointestinais/genética , Receptores de Neuropeptídeos/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Jejum , Regulação da Expressão Gênica , Intestinos/citologia , Simulação de Acoplamento Molecular , Motilina/química , Motilina/metabolismo , Filogenia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores dos Hormônios Gastrointestinais/química , Receptores dos Hormônios Gastrointestinais/metabolismo , Receptores de Neuropeptídeos/química , Receptores de Neuropeptídeos/metabolismo , Análise de Sequência de DNA
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