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1.
Biol Pharm Bull ; 46(11): 1601-1608, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37722878

RESUMO

The involvement of serotonin (5-HT) and/or noradrenaline in acute pruriceptive processing in the central nervous system (CNS) has been reported using antidepressants, such as milnacipran, a serotonin and noradrenaline reuptake inhibitor, and mirtazapine, a noradrenergic and specific serotonergic antidepressant; however, the roles of 5-HT receptor family in acute pruriceptive processing have not been fully elucidated in the CNS. In the present study, scratching behavior induced by chloroquine (CQ) was ameliorated by milnacipran or mirtazapine, and these effects were reversed by SB207266, a 5-HT4 antagonist, or SB258585, a 5-HT6 antagonist, but not by SB258585, a 5-HT5 antagonist. Moreover, CQ-induced scratches were mitigated by intrathecal injection of 5-HT4 agonists, such as BIMU8 and ML10302, and the 5-HT6 agonist, WAY208466. Conversely, histamine-induced scratches were not affected by the 5-HT4 agonists or a 5-HT6 agonist. Similarly, the amelioration of histamine-induced scratches by these antidepressants was not reversed by the 5-HT4, 5-HT5, or 5-HT6 receptor antagonist. Therefore, 5-HT is involved in the amelioration of CQ-induced scratches by milnacipran and mirtazapine, and 5-HT4, 5-HT5, and 5-HT6 receptors play differential roles in acute pruriceptive processing after administration of CQ or histamine.


Assuntos
Histamina , Serotonina , Camundongos , Animais , Serotonina/farmacologia , Mirtazapina , Antidepressivos/farmacologia , Milnaciprano , Norepinefrina
2.
Medicina (Kaunas) ; 59(10)2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37893534

RESUMO

Background and Objectives: Allergic contact dermatitis is a common type IV hypersensitivity reaction characterised by redness, itching, oedema and thickening of the skin. It occurs in about 7% of the population and its incidence is increasing. It has been observed that the preconditioning of tissues by exposing them to transient ischemia increases resistance to subsequent permanent ischemia, and this phenomenon is called ischemic preconditioning. It has been shown that conditioning in one organ can also protect other organs. The protective effect of remote ischemic preconditioning is thought to be based on the induction of anti-inflammatory responses. The aim of this project was to investigate the anti-inflammatory and antipruritic effects of remote ischemic postconditioning in a mouse model of experimental allergic contact dermatitis. Methods: Experimental allergic contact dermatitis was induced with 1-fluoro-2,4-dinitrobenzene. Remote ischemic postconditioning was performed at 3 and 25 h after the challenge. Ear thickness and number of scratches 24 and 48 h after challenge, as well as cytokine levels and the infiltration of mast cells, neutrophils, CD4+ and CD8+ T lymphocytes in serum and ear tissue at 48 h were measured to determine the effect of RIPsC. Results: Remote ischemic postconditioning decreased ear thickness, one of the symptoms of allergic contact dermatitis (p < 0.0001). It had no significant effect on the number of scratches. It reduced serum IL-17 levels (p < 0.01). It alleviated local inflammation by suppressing CD8+ T lymphocyte and neutrophil infiltration. Conclusions: It was concluded that remote ischemic postconditioning may alleviate the symptoms of allergic contact dermatitis by suppressing CD8+ T lymphocyte and neutrophil infiltration and reducing IL-17 secretion.


Assuntos
Dermatite Alérgica de Contato , Pós-Condicionamento Isquêmico , Camundongos , Animais , Antipruriginosos/uso terapêutico , Interleucina-17 , Dermatite Alérgica de Contato/tratamento farmacológico , Anti-Inflamatórios/uso terapêutico , Isquemia
3.
Biochem Biophys Res Commun ; 534: 624-631, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33220930

RESUMO

In the present study, we demonstrated that there is a direct relationship between scratching behaviors induced by itch and functional changes in the brain reward system. Using a conditional place preference test, the rewarding effect was clearly evoked by scratching under both acute and chronic itch stimuli. The induction of ΔFosB, a member of the Fos family of transcription factors, was observed in dopamine transporter (DAT)-positive dopamine neurons in the ventral tegmental area (VTA) of mice suffering from a chronic itch sensation. Based on a cellular analysis of scratching-activated neurons, these neurons highly expressed tyrosine hydroxylase (TH) and DAT genes in the VTA. Furthermore, in an in vivo microdialysis study, the levels of extracellular dopamine in the nucleus accumbens (NAcc) were significantly increased by transient scratching behaviors. To specifically suppress the mesolimbic dopaminergic pathway using pharmacogenetics, we used the TH-cre/hM4Di mice. Pharmacogenetic suppression of mesolimbic dopaminergic neurons significantly decreased scratching behaviors. Under the itch condition with scratching behaviors restricted by an Elizabethan collar, the induction of ΔFosB was found mostly in corticotropin-releasing hormone (CRH)-containing neurons of the hypothalamic paraventricular nucleus (PVN). These findings suggest that repetitive abnormal scratching behaviors under acute and chronic itch stimuli may activate mesolimbic dopamine neurons along with pleasant emotions, while the restriction of such scratching behaviors may initially induce the activation of PVN-CRH neurons associated with stress.


Assuntos
Prurido/fisiopatologia , Prurido/psicologia , Recompensa , Área Tegmentar Ventral/fisiopatologia , Doença Aguda , Animais , Comportamento Animal/fisiologia , Doença Crônica , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Expressão Gênica , Histamina/administração & dosagem , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Núcleo Accumbens/fisiopatologia , Testes Farmacogenômicos , Cloreto de Picrila/administração & dosagem , Prurido/genética , Tirosina 3-Mono-Oxigenase/genética
4.
Biochem Biophys Res Commun ; 533(4): 1102-1108, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33028486

RESUMO

An itch is defined as an unpleasant sensation that evokes a desire to scratch. Glutamate is a major excitatory neurotransmitter in the mammalian central nervous system and has a crucial role in pruriceptive processing in the spinal dorsal horn. It is well known that glutamate exerts its effects by binding to various glutamate receptors including α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, and that AMPA/kainate receptors play a crucial role in pruriceptive processing; however, the precise role of AMPA receptors remains uncertain. Perampanel, an antiepileptic drug, is an antagonist of AMPA receptors. Pretreatment with perampanel dose-dependently attenuated the induction of scratching, a behavior typically associated with pruritus, by intradermal administration of the pruritogen chloroquine. In addition, the induction of scratching in mice painted with diphenylcyclopropenone and NC/Nga mice treated with Biostir AD, animal models of contact dermatitis and atopic dermatitis, respectively, was dose-dependently alleviated by administration of perampanel. These findings indicate that AMPA receptors play a crucial role in pruriceptive processing in mice with acute or chronic pruritus.


Assuntos
Comportamento Animal/efeitos dos fármacos , Prurido/tratamento farmacológico , Prurido/metabolismo , Piridonas/administração & dosagem , Receptores de AMPA/metabolismo , Animais , Cloroquina/toxicidade , Ciclopropanos/toxicidade , Modelos Animais de Doenças , Histamina/toxicidade , Hipodermóclise , Injeções Espinhais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nitrilas , Piridonas/uso terapêutico , Quinoxalinas/administração & dosagem , Quinoxalinas/uso terapêutico , Receptores de AMPA/antagonistas & inibidores
5.
Immunopharmacol Immunotoxicol ; 39(5): 292-295, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28745076

RESUMO

OBJECTIVE: In this study, we aimed to study the effects of ICI204,448, naloxone methiodide and levocetirizine on the scratching behavior induced by intradermal injection of a ?-opioid antagonist, nor-binaltorphimine (nor-BNI), into the rostral back of ICR mice were investigated. MATERIALS AND METHODS: Male ICR mice weighing 30?35 g were used. The number of scratching episodes were counted for 60 min after i.d. injection of nor-BNI. RESULTS: nor-BNI dose dependently increased in the number of scratching episodes in ICR mice. nor-BNI-induced scratching behavior was inhibited by not only nalfurafine but also ICI204,448, a peripherally selective ?-opioid agonist. Naloxone and naloxone methiodide, a peripherally restricted ?-opioid antagonist, also inhibited nor-BNI-induced scratching behavior. Scratching behavior induced by nor-BNI was inhibited by chlorpheniramine as well as levocetirizine, a third-generation H1 antagonist that does not cross into the CNS. CONCLUSION: These results suggest that scratching behavior induced by this ?-opioid antagonist, nor-BNI, is related to not only central but also peripheral opioid and H1 receptors.


Assuntos
Comportamento Animal/efeitos dos fármacos , Cetirizina/farmacologia , Naloxona/análogos & derivados , Naltrexona/análogos & derivados , Antagonistas de Entorpecentes/farmacologia , Pirrolidinas/farmacologia , Animais , Masculino , Camundongos , Camundongos Endogâmicos ICR , Naloxona/farmacologia , Naltrexona/farmacologia , Compostos de Amônio Quaternário/farmacologia
6.
Biosci Biotechnol Biochem ; 78(9): 1568-71, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25209505

RESUMO

Nodakenin, derived from the roots of Angelica gigas Nakai, is an important natural resource and medicinal material with anti-allergic and anti- inflammatory activities. We have previously shown that nodakenin inhibits IgE/Ag-induced degranulation in mast cells. In this study, we investigated the inhibitory effect of nodakenin on 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis (AD)- like skin lesions in ICR mice. Scratching behavior, skin severity score, blood IgE level, and skin thickness were improved in DNCB-induced AD-like ICR mice. Our results showed that nodakenin suppressed the increase of AD-like skin lesions in ICR mice. These results suggest that nodakenin may be a potential therapeutic resource for AD as well as an adjunctive agent to control itching associated with AD.


Assuntos
Cumarínicos/administração & dosagem , Dermatite Atópica/tratamento farmacológico , Glucosídeos/administração & dosagem , Prurido/tratamento farmacológico , Pele/efeitos dos fármacos , Angelica/química , Animais , Degranulação Celular/efeitos dos fármacos , Dermatite Atópica/induzido quimicamente , Dermatite Atópica/metabolismo , Humanos , Camundongos , Nitrobenzoatos/toxicidade , Prurido/induzido quimicamente , Prurido/patologia , Pele/patologia
7.
Artigo em Inglês | MEDLINE | ID: mdl-39177810

RESUMO

RATIONALE: Despite variants in the Dlgap1 gene having the two lowest p-value in a genome-wide association study of obsessive compulsive disorder (OCD), previous studies reported the absence of OCD-like phenotypes in Dlgap1 knockout (KO) mice. Since these studies observed behavioral phenotypes only for a short period, development of OCD-like phenotypes in these mice at older ages was still plausible. OBJECTIVE: To examine the presence or absence of development of OCD-like phenotypes in Dlgap1 KO mice and their responsiveness to fluvoxamine. METHODS AND RESULTS: Newly produced Dlgap1 KO mice were observed for a year. Modified SHIRPA primary screen in 2-month-old homozygous mutant mice showed only weak signs of anxiety, stress conditions and aggression. At older ages, however, these mutant mice exhibited excessive self-grooming characterized by increased scratching which led to skin lesions. A significant sex difference was observed in this scratching behavior. The penetrance of skin lesions reached 50% at 6-7 months of age and 90% at 12 months of age. In the open-field test performed just after the appearance of these lesions, homozygous mutant mice spent significantly less time in the center, an anxiety-like behavior, than did their wild-type and heterozygous littermates, none and less than 10% of which showed skin lesions at 1 year, respectively. The skin lesions and excessive self-grooming were significantly alleviated by two-week treatment with fluvoxamine. CONCLUSION: Usefulness of Dlgap1 KO mice as a tool for investigating the pathogenesis of OCD-like phenotypes and its translational relevance was suggested.

8.
J Appl Anim Welf Sci ; 26(3): 313-324, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34279154

RESUMO

Preference responses of cats for scratching fabrics commonly used on furniture were evaluated during four consecutive days in three Non-Governmental Organizations (NGOs) that rescue companion animals. Cats were grouped and their choices were registered at a group level (no individual identification). Daily choices for chenille, suede, synthetic leather, or waterproof grosgrain fabrics were evaluated for the cats' groups. A preference for chenille and non-preference for synthetic leather and waterproof grosgrain was found, independent of the NGO. In conclusion, although not using chenille does not assure that cats stop scratching furniture - especially if no other option to scratch is available - synthetic leather and waterproof grosgrain seem to be less attractive fabrics for these animals. Further studies are needed to investigate whether these findings apply to cats in a home scenario, when just one or a few individuals are usually present and only one type of fabric covering furniture is commonly available. Although we did not investigate the effect of providing scratching posts for these animals, we recommend such posts are available in the environment as scratching behavior is important to cats.


Assuntos
Comportamento Animal , Decoração de Interiores e Mobiliário , Animais , Comportamento Animal/fisiologia
9.
Eur J Pharmacol ; 957: 175998, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37597648

RESUMO

Pruritus, including neuropathic and psychogenic pruritus, is an unpleasant feeling that causes a desire to scratch, which negatively impacts physical and psychological aspects of daily life. Nonetheless, little is known about the neural mechanisms involved in pruritus. Glutamate is a predominant excitatory neurotransmitter in the mammalian central nervous system and exerts its effects by binding to various glutamate receptors, including kainate (KA) receptors; however, the precise involvement of each glutamate receptor in pruriceptive processing remains unclear, particularly that of KA receptors. Therefore, the roles of KA receptors in histamine-dependent and -independent itch were investigated using CNQX, an AMPA/KA receptors antagonist, UBP310 and UBP302, antagonists of KA receptors, and small interfering (si)RNAs against KA receptor subunits in mice with acute and chronic pruritus. The effects of KA receptor antagonists on histamine-induced c-Fos expression in the spinal cord were also examined. The intrathecal administration of CNQX reduced the number of scratching events induced by histamine and chloroquine. On the other hand, UBP310 or UBP302 and the siRNAs of KA receptor subunits 1-3 significantly inhibited the induction of scratching events in mice treated with histamine, while no significant change was observed in the induction of spontaneous scratching events in mice with chronic pruritus. In addition, antagonists of KA receptors attenuated c-Fos expression in the superficial layers of the dorsal horn induced by histamine. These results indicate that KA receptors are involved in acute pruriceptive processing in the spinal cord induced by histamine, but not chloroquine or chronic itch.


Assuntos
Histamina , Receptores de Ácido Caínico , Animais , Camundongos , 6-Ciano-7-nitroquinoxalina-2,3-diona , Medula Espinal , Cloroquina , Antagonistas de Aminoácidos Excitatórios , Ácido Glutâmico , Prurido , RNA Interferente Pequeno , Mamíferos
10.
Pharmaceuticals (Basel) ; 16(12)2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38139833

RESUMO

Itch (pruritus) is a sensation in the skin that provokes the desire to scratch. The sensation of itch is mediated through a subclass of primary afferent sensory neurons, termed pruriceptors, which express molecular receptors that are activated by itch-evoking ligands. Also expressed in pruriceptors are several types of Transient Receptor Potential (TRP) channels. TRP channels are a diverse class of cation channels that are responsive to various somatosensory stimuli like touch, pain, itch, and temperature. In pruriceptors, TRP channels can be activated through intracellular signaling cascades initiated by pruritogen receptors and underly neuronal activation. In this review, we discuss the role of TRP channels TRPA1, TRPV1, TRPV2, TRPV3, TRPV4, TRPM8, and TRPC3/4 in acute and chronic pruritus. Since these channels often mediate itch in association with pruritogen receptors, we also discuss Mas-related G-protein-coupled receptors (Mrgprs) and protease-activated receptors (PARs). Additionally, we cover the exciting therapeutic targets amongst the TRP family, as well as Mrgprs and PARs for the treatment of pruritus.

11.
Front Physiol ; 13: 939281, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35936901

RESUMO

The evaluation of scratching behavior is important in experimental animals because there is significant interest in elucidating mechanisms and developing medications for itching. The scratching behavior is classically quantified by human observation, but it is labor-intensive and has low throughput. We previously established an automated scratching detection method using a convolutional recurrent neural network (CRNN). The established CRNN model was trained by white mice (BALB/c), and it could predict their scratching bouts and duration. However, its performance in black mice (C57BL/6) is insufficient. Here, we established a model for black mice to increase prediction accuracy. Scratching behavior in black mice was elicited by serotonin administration, and their behavior was recorded using a video camera. The videos were carefully observed, and each frame was manually labeled as scratching or other behavior. The CRNN model was trained using the labels and predicted the first-look videos. In addition, posterior filters were set to remove unlikely short predictions. The newly trained CRNN could sufficiently detect scratching behavior in black mice (sensitivity, 98.1%; positive predictive rate, 94.0%). Thus, our established CRNN and posterior filter successfully predicted the scratching behavior in black mice, highlighting that our workflow can be useful, regardless of the mouse strain.

12.
Front Mol Neurosci ; 15: 934564, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36277491

RESUMO

Previously the effect of the pruritogens, such as histamine and chloroquine, was tested in 11 inbred mouse strains, and this study aimed to identify resistant and sensitive strains, consistent with the observation that underlies the large variability in human populations. In the present study, we used the low responder C3H/HeJ (C3H) and the more sensitive C57BL/6J (C57) strain to find out if resistance and sensitivity to develop pruritus is restricted to only histamine and chloroquine or extends to other known pruritogens as well. We tested five additional commonly known pruritogens. We established dose-response relationships by injecting four concentrations of the pruritogens in the range of 0.3, 1, 3, and ten-fold in the nuchal fold. Then we assessed the scratching behavior for 30 min after injection with an automated custom-designed device based on the bilateral implantation of mini-magnets in the hind paws and on single cages placed within a magnetic coil. We found that the resistance to pruritogens is a general phenotype of the C3H strain and extends to all pruritogens tested, including not only histamine and chloroquine, but also endothelin, trypsin, 5-HT (serotonin), the short peptide SLIGRL, and Lysophosphatidic acid (LPA). C57 was more sensitive to all pruritogens and, in contrast to C3H, dose-response relationships were evident for some of the pruritogens. In general, comparable peak scratch responses were observed for the 0.3-fold concentrations of the pruritogens in C57 whereas C3H required at least the ten-fold concentration and still displayed only between 5 and 33% of the scratch responses observed in C57 for the respective pruritogen. The general resistance to pruritogens and the low level of scratching behavior found in the C3H strain is an interesting trait and represents a model for the study of the heritability of itch. It is accompanied in C3H with a higher sensitivity in assays of nociception.

13.
Neurol Res ; 44(6): 524-533, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35001813

RESUMO

BACKGROUND: The aim of the experiment was to investigate the effects of treadmill exercise on postthoracotomy pain and the expression of spinal pro-inflammatory and anti-inflammatory cytokines. METHODS: Animals were randomly distributed into four groups: (a) sham surgery, (b) rats following 60 min thoracotomy and rib retraction (thoracotomy), (c) thoracotomy rats received treadmill training (thoracotomy+treadmill), and (d) sham surgery rats received treadmill training (sham surgery+treadmill). Treadmill workouts were started on postoperative day 10 (POD10) and lasted for 6 weeks (5 days per week). Rats were examined for cold allodynia using acetone and mechanical allodynia using von Frey hairs (in grams) at the surgical site. Spinal pro-inflammatory and anti-inflammatory cytokines were analyzed on PODs 28 and 49. RESULTS: Both thoracotomy and thoracotomy+treadmill groups exhibited a decrease in mechanical force thresholds (g) and an increase in scratches per min on POD10. Mechanical hypersensitivity and incremental scratches lasted from POD14 and POD49 in the thoracotomy group. Although force thresholds and scratches remained not return to baseline, incremental force thresholds (p < 0.001) and diminutive scratches (p < 0.001) occurred after 6-week treadmill workouts. The rise in spinal interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α) concentrations or the decline in spinal IL-10 concentration in thoracotomy+treadmill rats was less (p < 0.05) than thoracotomy rats without exercise. CONCLUSIONS: Mechanical allodynia using von Frey filament testing and cold allodynia by acetone testing were improved in thoracotomy rats after treadmill workouts.. Treadmill exercise restrained excess pro-inflammatory cytokine expression but increased anti-inflammatory cytokine level in a rib retraction model.


Assuntos
Hiperalgesia , Doenças do Sistema Nervoso Periférico , Acetona/metabolismo , Acetona/uso terapêutico , Animais , Anti-Inflamatórios/uso terapêutico , Citocinas/metabolismo , Hiperalgesia/tratamento farmacológico , Ratos , Ratos Sprague-Dawley , Medula Espinal/metabolismo , Toracotomia/efeitos adversos
14.
Neuron ; 109(19): 3075-3087.e2, 2021 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-34411514

RESUMO

Itch is a discrete and irritating sensation tightly coupled to a drive to scratch. Acute scratching developed evolutionarily as an adaptive defense against skin irritants, pathogens, or parasites. In contrast, the itch-scratch cycle in chronic itch is harmful, inducing escalating itch and skin damage. Clinically and preclinically, scratching incidence is currently evaluated as a unidimensional motor parameter and believed to reflect itch severity. We propose that scratching, when appreciated as a complex, multidimensional motor behavior, will yield greater insight into the nature of itch and the organization of neural circuits driving repetitive motor patterns. We outline the limitations of standard measurements of scratching in rodent models and present new approaches to observe and quantify itch-evoked scratching. We argue that accurate quantitative measurements of scratching are critical for dissecting the molecular, cellular, and circuit mechanisms underlying itch and for preclinical development of therapeutic interventions for acute and chronic itch disorders.


Assuntos
Prurido/fisiopatologia , Animais , Modelos Animais de Doenças , Cães , Humanos , Camundongos , Prurido/terapia , Ratos
15.
Eur J Pharmacol ; 911: 174513, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34555396

RESUMO

The roles of serotonin (5-HT) and/or noradrenaline in acute pruriceptive processing have been demonstrated using antidepressants, such as milnacipran, a serotonin and noradrenaline reuptake inhibitor, and mirtazapine, a noradrenergic and specific serotonergic antidepressant; however, the involvement of 5-HT in acute pruriceptive processing has not yet been elucidated in detail. Scratching events induced by chloroquine (CQ) were attenuated by the administration of milnacipran or mirtazapine, and these effects were reversed by a treatment with ondansetron, a 5-HT3 antagonist, or SB26970, a 5-HT7 antagonist. CQ-induced scratching events were also ameliorated by the intrathecal administration of 5-HT, SR572227A and RS56812 (5-HT3 agonists), and LP211 and LP44 (5-HT7 agonists), indicating the modulation of CQ-induced scratching events by 5-HT and noradrenaline. By contrast, histamine-induced scratching events were not markedly affected by the administration of 5-HT and 5-HT7 agonists, whereas 5-HT3 agonists exerted attenuating effects. Similarly, they were not clearly reversed by the administration of the 5-HT7 antagonist, unlike a 5-HT3 antagonist. Therefore, 5-HT is involved in the attenuating effects of milnacipran and mirtazapine on CQ- and histamine-induced scratching events, and 5-HT3 and 5-HT7 receptors play different roles in pruriceptive processing induced by histamine or CQ.


Assuntos
Serotonina
16.
Biomed Pharmacother ; 129: 110488, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32768968

RESUMO

Atopic dermatitis (AD) is a chronic inflammatory skin disease that is associated with intestinal microflora. Since specific probiotics may have better efficacy for AD, we determined the efficacy of Pediococcus acidilactici SRCM102024 (PA) for treating AD in HaCaT cells and NC/Nga mice and explored the mechanism of action. AD-like pathology was induced in HaCaT cells and the dorsal skin of Nc/Nga mice by local exposure to 2,4-dinitrochlorobenzene (DNCB). In AD-lesion induced mice, PA in low-, medium- and high-dosages (5 × 10E6, 5 × 10E7 and 5 × 10E8 CFU/kg bw, respectively) and dexamethasone (3 mg/kg bw, positive-control) were orally administered for 5 weeks. The clinical AD severity, serum immunoglobulin E (IgE) and TNF-α, gene expressions of interleukin (IL)-4, IL-13, and TNF-α and gut microflora were measured. PA treatment (100-300 CFU/mL) dose-dependently increased cell survival in DNCB-induced HACAT cells. PA reduced the relative mRNA expression of PAR-2, TNF-α, IL-4 and IL-13 in the cells. In dorsal skin of Nc/Nga mice applied with DNCB, PA dose-dependently attenuated erythema, hemorrhage, edema, excoriation, dryness and scratching behavior and PA-H improved the clinical symptoms similar to the positive-control. PA-M and PA-H treatment significantly prevented the disturbance of the dorsal skin tissues and decreased the inflammatory cellular infiltrate of mast cells, compared to the control. PA dose-dependently reduced serum IgE and TNF-α concentrations and the mRNA expression of TNF-α, IL-4, and IL-13 in dorsal skin. In gut microflora, relative counts of Lactobacillales, Butyricicoccus and Ruminococcus were decreased in the AD-control compared to the positive-control and the PA-M and PA-H prevented their decrease. However, the positive-control increased serum AST and ALT activities, indicating liver damage as an adverse effect. In conclusion, oral treatment of PA (human equivalent 1 × 10E9-1 × 10E10) relieved the AD symptoms by dose-dependently preventing over-activation of the immune response. Oral PA intake may be a safe and effective alternative therapy for AD.


Assuntos
Dermatite Atópica/terapia , Microbioma Gastrointestinal , Mucosa Intestinal/microbiologia , Mucinas/metabolismo , Pediococcus acidilactici/fisiologia , Probióticos/administração & dosagem , Pele/patologia , Animais , Linhagem Celular , Doença Crônica , Citocinas/genética , Citocinas/metabolismo , Dermatite Atópica/metabolismo , Dermatite Atópica/microbiologia , Dermatite Atópica/patologia , Dinitroclorobenzeno , Modelos Animais de Doenças , Humanos , Imunoglobulina E/sangue , Mucosa Intestinal/metabolismo , Masculino , Camundongos , Índice de Gravidade de Doença , Pele/metabolismo , Regulação para Cima
17.
Neuroscience ; 444: 54-63, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32750381

RESUMO

Itch induces a desire to scratch and leads to skin damage in some severe conditions. Much progress has been made in the peripheral and spinal level, and recent findings suggested that we need to focus on the central circuitry mechanism. However, the functional role of the thalamus in itch signal processing remains largely unknown. We showed that the posterior thalamic nucleus (Po) played a vital role in modulating facial histaminergic itch signal processing. We found that the calcium signal of Po neurons was increased during the histaminergic itch-induced scratching behavior in the cheek model, and pharmacogenetic suppression of Po neurons reduced the scratching behaviors. Retrograde mapping results suggested that the Po receives information from the somatosensory cortex, motor cortex, parabrachial nucleus (PBN), the principal sensory trigeminal nucleus (PrV) and the spinal trigeminal nucleus (SpV), which participate in itch signal transmission from head and body. Thus, our study indicates that the Po is critical in modulating facial histaminergic itch signal processing.


Assuntos
Núcleos Parabraquiais , Núcleos Posteriores do Tálamo , Humanos , Prurido , Córtex Somatossensorial , Núcleo Espinal do Trigêmeo
18.
J Feline Med Surg ; 21(8): 691-699, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30152710

RESUMO

OBJECTIVES: The objective of this study was to determine kitten preferences towards different scratchers and the effects of catnip and cat odor on kitten scratching behaviors. METHODS: Two-choice preference tests were conducted to compare scratchers and preferred scratchers with or without additives (ie, catnip, catnip oil, cat hair) in six studies. Kittens (n = 40, <8 weeks old) had access to two scratchers on the floor of a simulated living room for 20 mins and interactions were video-recorded. The time each kitten spent scratching each scratcher was compared. RESULTS: In study 1, the S-shaped cardboard was preferred over a hemp post with a toy on top, and no difference was observed in the other pairs of scratchers compared. In study 2, the S-shaped cardboard was preferred by kittens compared with a raised scratcher covered with window screen or with carpet, and no differences were observed between the latter two scratchers. In study 3, the scratcher covered with window screen set upright was preferred over the same scratcher laid horizontally on the floor. The S-shaped cardboard was preferred over the scratcher covered with bubble wrap. In study 4, kittens preferred the S-shaped cardboard over the scratchers covered with window screen or short-fiber carpet but not over the scratcher covered with long-fiber carpet. In study 5, the S-shaped cardboard was strongly preferred over the long cardboard and rectangular cardboard but not over the boat-shaped cardboard. In study 6, dried catnip plant, catnip oil spray or the hair from other cats did not alter the scratching behavior exhibited by the kittens vs the control S-shaped cardboard alone. CONCLUSIONS AND RELEVANCE: The S-shaped cardboard scratcher was a preferred scratcher for kittens. Catnip or odor of other cats did not alter this behavior in kittens. S-shaped cardboard may be a preferred scratching device for kittens.


Assuntos
Comportamento Animal/fisiologia , Gatos/fisiologia , Gatos/psicologia , Animais , Desenho de Equipamento , Nepeta
19.
J Feline Med Surg ; 21(3): 235-243, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30810089

RESUMO

PRACTICAL RELEVANCE: While scratching is a normal, beneficial behavior for cats, it can create problems when cats scratch objects owners deem as inappropriate. However, if veterinarians make suitable recommendations from the first veterinary visit, owners will be able to implement effective preventive strategies to develop good scratching patterns for life. Educating owners as to why cats scratch, how to guide cats to scratch only on desirable surfaces (ie, a scratching post), which types of scratching posts are preferred by most cats, the benefits of pheromone products, as well as other strategies to avoid destructive scratching, helps to preserve the cat-owner bond and reduces the risk of relinquishment. CLINICAL CHALLENGES: Clients may not directly ask veterinarians for their assistance regarding their cat's destructive scratching, and may not be aware that anything can be done except for declawing their cat. EVIDENCE BASE: Published studies on scratching are limited. Destructive scratching has been documented as a reason for the relinquishment of cats to shelters and the negative effects of declaw surgeries are being increasingly discovered. Among recent scientific publications are studies assessing kitten and cat preferences for scratching substrates, and the use of pheromones to encourage appropriate scratching behavior. This review draws on these studies, among other resources, as well as the authors' personal experiences.


Assuntos
Comportamento Animal/efeitos dos fármacos , Gatos/fisiologia , Feromônios/uso terapêutico , Animais , Médicos Veterinários
20.
J Microbiol Biotechnol ; 29(5): 827-837, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-30982315

RESUMO

The present study was conducted with the aim to investigate the ameliorative effects of a new soybean product (cheonggukjang) fermented with Bacillus amyloliquefaciens SCGB1 (SFBA) in atopic dermatitis (AD) mouse model. Visual evaluation of AD induction in the mice indicated the remarkable control of SFBA in reducing the pathological severity of AD-like skin lesions reported as the SCORAD score of AD clinical symptoms. The results revealed that SFBA reduced dorsal skin and epidermal thickness to a similar extent with prednisolone. Further analysis revealed the dominance of SFBA in restraining mast cell infiltration in the dermis; immunoglobulin-E expression in serum; and TH2 IL-4 cytokine and itch-related IL-31 cytokine in the mice skin and serum. SFBA also suppressed scratching behaviours in mice induced by compound 48/80. Further histological findings also revealed the alleviation of collagen fiber deposition in dermal skin of the AD mice model. These actions of SFBA were examined to be mediated by its suppression of the phosphorylation activation of key signalling molecules such as NF-kappaB and MAPK responsible for the induction of cytokine production. Thus, SFBA can be considered as a promising functional food for managing clinical, histological and immunological spectra associated with AD.


Assuntos
Bacillus amyloliquefaciens/metabolismo , Dermatite Atópica/tratamento farmacológico , Alimentos Fermentados , Glycine max/metabolismo , Interleucinas/metabolismo , Mastócitos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Dermatopatias/tratamento farmacológico , Animais , Citocinas/metabolismo , Dermatite Atópica/patologia , Modelos Animais de Doenças , Hiperplasia Epitelial Focal/tratamento farmacológico , Hiperplasia Epitelial Focal/patologia , Imunoglobulina E/sangue , Masculino , Camundongos , República da Coreia , Pele/patologia , Dermatopatias/patologia
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