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1.
J Pharmacol Exp Ther ; 374(1): 200-210, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32265323

RESUMO

Both an agonist and its associated prodrug for metabotropic glutamate2/3 (mGlu2/3) receptors demonstrated anxiolytic efficacy in large, randomized, multicenter, double-blind, placebo-controlled trials studying patients with generalized anxiety disorder (GAD). These mGlu2/3 receptor agonists produced robust preclinical anxiolytic-like effects in rodent models. Several different metabotropic glutamate2 receptor positive allosteric modulators have been found to produce antidepressant-like effects on several preclinical screening paradigms, including differential-reinforcement-of-low-rate 72-second (DRL 72-s) behavior [increased reinforcers, decreased response rate, and cohesive rightward shifts in inter-response time distributions]. Although mGlu2/3 receptor agonists have not been tested formally for therapeutic effects in treating patients with major depressive disorder, these compounds generally fail to exert antidepressant-like effects in preclinical screening paradigms and did not improve depressive symptoms in GAD trials. Thus, the present studies were designed to test the potential antidepressant-like effects of the mGlu2/3 receptor agonist 1S,2S,5R,6S-2-aminobicyclo[3.1.0]hexane-2,6-bicarboxylate monohydrate (LY354740) on the DRL 72-s schedule. LY354740 did not test similarly to clinically validated antidepressant drugs when administered alone or when coadministered with the selective serotonin reuptake inhibitor fluoxetine in rats. Another glutamate-based antidepressant drug, the uncompetitive N-methyl-D-aspartate channel blocker racemic ketamine, exerted antidepressant-like effects when administered at subanesthetic doses in rats. The findings further support the specificity of rat DRL 72-s behavior when screening for anxiolytic versus antidepressant drugs and extend testing of compounds with glutamatergic mechanisms of action. SIGNIFICANCE STATEMENT: The metabotropic glutamate2/3 receptor agonist and clinically validated anxiolytic drug 1S,2S,5R,6S-2-aminobicyclo[3.1.0]hexane-2,6-bicarboxylate monohydrate did not test similar to antidepressant drugs (increased reinforcers, decreased response rate, and cohesive rightward shifts in the inter-response time distribution) when tested on differential-reinforcement-of-low-rate 72-second (DRL 72-s) behavior and also did not enhance the antidepressant-like effects of the serotonin reuptake inhibitor fluoxetine. The uncompetitive N-methyl-D-aspartate receptor antagonist ketamine increased the reinforcement rate, decreased the response rate, and induced a rightward shift in the inter-response time distribution similar to antidepressant drugs; these results confirm the utility of DRL 72-s schedule of reinforcement when testing clinically validated anxiolytic versus antidepressant glutamatergic drugs.


Assuntos
Ansiolíticos/farmacologia , Antidepressivos/farmacologia , Comportamento Animal/efeitos dos fármacos , Ácido Glutâmico/metabolismo , Reforço Psicológico , Animais , Compostos Bicíclicos com Pontes/farmacologia , Cognição/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Função Executiva/efeitos dos fármacos , Comportamento Impulsivo/efeitos dos fármacos , Ketamina/farmacologia , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
2.
J Fish Dis ; 43(6): 687-695, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32315094

RESUMO

This study compared the in vitro anthelmintic activity of Copaifera reticulata oleoresin (200, 400, 600, 800 and 1,000 mg/L) and of nanoemulsions prepared with this oleoresin (50, 100, 150, 200 and 250 mg/L) against monogeneans on the gills of Colossoma macropomum. The major compounds present in the oleoresin of C. reticulata were γ-macrocarpene (14.2%), α-bergamotene (13.6%), ß-selinene (13.4%) and ß-caryophyllene (11.7%). All concentrations of the nanoemulsion and the oleoresin without nanoformulation showed anthelmintic efficacy against monogeneans, and higher concentrations led to more rapid parasite mortality. Structural damages to the tegument of the parasites exposed to C. reticulata oleoresin were observed with scanning electron microscopy. At two hours of exposure, fish showed 100% tolerance to all nanoemulsion concentrations used in the in vitro assays, whereas 100% mortality was shown in the fish exposed to the oleoresin without nanoformulation after one hour. The results of this study suggest that nanoemulsions with oleoresin of C. reticulata have advantages in the control and treatment of monogenean infections in C. macropomum when compared to the oleoresin without nanoformulation. In addition, since nanoemulsions with the C. reticulata oleoresin are safe to control monogeneans, the efficacy of these nanoformulations may be assayed in therapeutic baths to treat C. macropomum infected by monogeneans.


Assuntos
Antiplatelmínticos/farmacologia , Fabaceae/química , Doenças dos Peixes/tratamento farmacológico , Extratos Vegetais/farmacologia , Trematódeos/efeitos dos fármacos , Infecções por Trematódeos/veterinária , Animais , Compostos Bicíclicos com Pontes/farmacologia , Relação Dose-Resposta a Droga , Emulsões/química , Doenças dos Peixes/parasitologia , Nanoestruturas/química , Sesquiterpenos Policíclicos/farmacologia , Sesquiterpenos de Eudesmano/farmacologia , Tetra-Hidronaftalenos/farmacologia , Infecções por Trematódeos/tratamento farmacológico , Infecções por Trematódeos/parasitologia
3.
Org Biomol Chem ; 18(13): 2410-2415, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32195526

RESUMO

Xylarilongipins A (1) and B (2), two diterpenes each with an unusual cage-like bicyclo[2.2.2]octane moiety, along with their biosynthetic precursor hymatoxin L (3), were isolated from the culture broth of the fungicolous fungus Xylaria longipes HFG1018 inhabiting in the medicinal fungus Fomitopsis betulinus. The structures and absolute configurations of the three compounds were established by extensive spectroscopic analysis and single-crystal X-ray diffraction analysis. Xylarilongipin A (1) displayed moderate inhibitory activity against the cell proliferation of concanavalin A-induced T lymphocytes and lipopolysaccharide-induced B lymphocytes with IC50 values of 13.6 and 22.4 µM, respectively. Additionally, the biosynthetic pathways for compounds 1-3 are discussed. This work not only corroborates the structure of the 9,16-cyclo-(18-nor-)isopimarane skeleton by single-crystal X-ray diffraction analysis for the first time, but also provides new insights into the biosynthetic origin of the unusual diterpene skeletons.


Assuntos
Compostos Bicíclicos com Pontes/farmacologia , Diterpenos/farmacologia , Imunossupressores/farmacologia , Compostos Bicíclicos com Pontes/química , Compostos Bicíclicos com Pontes/toxicidade , Linhagem Celular Tumoral , Diterpenos/química , Diterpenos/toxicidade , Humanos , Imunossupressores/química , Imunossupressores/toxicidade , Xylariales/química
4.
J Med Chem ; 63(6): 2833-2853, 2020 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-32026697

RESUMO

A series of chemical optimizations guided by in vitro affinity at the α4ß2 receptor in combination with selectivity against the α3ß4 receptor, pharmacokinetic evaluation, and in vivo efficacy in a forced swim test resulted in identification of 3-(6-chloropyridine-3-yloxymethyl)-2-azabicyclo[3.1.0]hexane hydrochloride (9h, SUVN-911) as a clinical candidate. Compound 9h is a potent α4ß2 receptor ligand with a Ki value of 1.5 nM. It showed >10 µM binding affinity toward the ganglionic α3ß4 receptor apart from showing selectivity over 70 other targets. It is orally bioavailable and showed good brain penetration in rats. Marked antidepressant activity and dose-dependent receptor occupancy in rats support its potential therapeutic utility in the treatment of depression. It does not affect the locomotor activity at doses several folds higher than its efficacy dose. It is devoid of cardiovascular and gastrointestinal side effects. Successful long-term safety studies in animals and phase-1 evaluation in healthy humans for safety, tolerability, and pharmacokinetics paved the way for its further development.


Assuntos
Antidepressivos/farmacologia , Antagonistas Nicotínicos/farmacologia , Piridinas/farmacologia , Receptores Nicotínicos/metabolismo , Administração Oral , Animais , Antidepressivos/administração & dosagem , Antidepressivos/química , Compostos Bicíclicos com Pontes/administração & dosagem , Compostos Bicíclicos com Pontes/química , Compostos Bicíclicos com Pontes/farmacologia , Depressão/tratamento farmacológico , Halogenação , Humanos , Masculino , Antagonistas Nicotínicos/administração & dosagem , Antagonistas Nicotínicos/química , Piridinas/administração & dosagem , Piridinas/química , Ratos , Ratos Wistar
5.
Microvasc Res ; 129: 103975, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31926201

RESUMO

Microvascular injury is a common pathological process in ischemia-reperfusion injury. Endothelial progenitor cells (EPCs) are vital cells for angiogenesis and endothelial repair. These cells can home to injury sites and secrete angiogenic growth factors. α7nAChRs are pivotal in cholinergic angiogenesis, which is associated with endothelial cells and EPCs. Our study was designed to determine whether activating α7nAChRs enhances the function of EPCs and to explore the underlying mechanism. EPCs were derived from the bone marrow of male Sprague-Dawley rats and treated with an α7nAChR agonist (PNU282987), an α7nAChR antagonist (MLA) and a JAK2 antagonist (AG490). We then assayed the angiogenic abilities of the EPCs, including proliferation ability, adhesion ability, migration ability and in vitro tube formation ability. The levels of total JAK2 (t-JAK2), phosphorylated JAK2 (p-JAK2), total STAT3 (t-STAT3) and phosphorylated STAT3 (p-STAT3) were estimated by western blot analysis. PNU282987 treatment facilitated the angiogenic abilities of EPCs compared with the control regimen. The western blot data suggested that PNU282987 increased the levels of p-JAK2 and p-STAT3. However, the differences in t-JAK2 levels and t-STAT3 levels between the agonist-treated group and the control group were not significant. Moreover, treating EPCs with AG490 reduced STAT3 phosphorylation and attenuated the PNU282987-induced enhancement of EPCs. We demonstrated that activating α7nAChRs can enhance EPC functions partially through the JAK2/STAT3 signaling pathway. This study reveals that α7nAChRs are potential therapeutic targets for angiogenesis and that the JAK2/STAT3 pathway plays a vital role in the associated therapeutic mechanism.


Assuntos
Benzamidas/farmacologia , Compostos Bicíclicos com Pontes/farmacologia , Células Progenitoras Endoteliais/efeitos dos fármacos , Janus Quinase 2/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Agonistas Nicotínicos/farmacologia , Fator de Transcrição STAT3/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/agonistas , Animais , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Células Progenitoras Endoteliais/metabolismo , Masculino , Fosforilação , Ratos Sprague-Dawley , Transdução de Sinais , Receptor Nicotínico de Acetilcolina alfa7/metabolismo
6.
Psychopharmacology (Berl) ; 237(1): 189-197, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31515584

RESUMO

RATIONALE: Psychiatric disorders such as anxiety and depression are frequently observed in neuropathic pain patients, and negatively impact their quality of life. Mirogabalin is a novel ligand for the α2δ subunit of voltage-gated calcium channels and has unique binding characteristics to α2δ subunits and potent and long-lasting analgesic effects in neuropathic pain models. OBJECTIVES: To provide further information on the pharmacological profile of mirogabalin and its utility for chronic pain therapy, we investigated its anxiolytic effects in an experimental animal model for neuropathic pain. METHODS: In chronic constriction injury (CCI) model rats, mechanical hypersensitivity was determined by the von Frey test. Anxiety- and depression-related behaviours were evaluated using the elevated plus maze test and forced swimming test, respectively. RESULTS: CCI model rats showed sustained tactile allodynia followed by anxiety-related behaviours, not depression-related behaviours. The tactile allodynia (significant decreases in paw withdrawal threshold) developed within 2 weeks after model preparation, whereas the anxiety-related behaviours (significant decreases in the number of entries and time spent in open arms and significant increases in time spent in closed arms) were observed at 5 weeks but not 4 weeks after model preparation. Single oral administration of mirogabalin (3 or 10 mg/kg) dose-dependently alleviated the above-mentioned anxiety-related behaviours and tactile allodynia. CONCLUSIONS: CCI model rats showed anxiety-related behaviours in a time-dependent manner in the elevated plus maze test. Mirogabalin alleviated both the anxiety-related behaviours and tactile allodynia in CCI model rats. Mirogabalin may provide effective anxiety relief as well as pain relief in patients with neuropathic pain.


Assuntos
Ansiolíticos/uso terapêutico , Ansiedade/tratamento farmacológico , Compostos Bicíclicos com Pontes/uso terapêutico , Neuralgia/tratamento farmacológico , Animais , Ansiolíticos/farmacologia , Comportamento Animal/efeitos dos fármacos , Compostos Bicíclicos com Pontes/farmacologia , Agonistas dos Canais de Cálcio/farmacologia , Agonistas dos Canais de Cálcio/uso terapêutico , Modelos Animais de Doenças , Hiperalgesia/tratamento farmacológico , Masculino , Ratos
7.
Nihon Yakurigaku Zasshi ; 154(6): 352-361, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31787689

RESUMO

Mirogabalin, a novel ligand for the α2δ subunit of voltage-gated calcium channels, has been approved for the treatment of peripheral neuropathic pain including painful diabetic peripheral neuropathy (DPNP) and postherpetic neuralgia (PHN) in Japan. Mirogabalin showed potent and selective binding affinities for the α2δ subunits, and slower dissociation rates for the α2δ-1 subunit than for the α2δ-2 subunit. It also showed potent and long-lasting analgesic effects in rat models of neuropathic pain, and wider safety margins for the central nervous system side effects. A pharmacological study using mutant mice demonstrated that the analgesic effects of mirogabalin were mediated by binding of the drug to the α2δ-1 subunit, not the α2δ-2 subunit. The pharmacological properties of mirogabalin can be associated with its unique binding characteristics. The bioavailability of mirogabalin is high and its plasma exposure increases dose-proportionally. Mirogabalin is mainly excreted via the kidneys in an unchanged form, thus, mirogabalin has a low possibility of undergoing drug-drug interaction, while dose adjustment based on the creatinine clearance level is specified in patients with renal impairment. In double-blind, placebo-controlled phase 3 studies in Asian patients with DPNP and PHN, mirogabalin showed significant and dose-dependent pain relief, and all tested doses of mirogabalin were well tolerated. In summary, mirogabalin has a balanced efficacy versus safety profile, and can provide an alternative therapeutic option for the treatment of peripheral neuropathic pain.


Assuntos
Analgésicos/farmacologia , Compostos Bicíclicos com Pontes/farmacologia , Animais , Ensaios Clínicos Fase III como Assunto , Método Duplo-Cego , Humanos , Camundongos , Ensaios Clínicos Controlados Aleatórios como Assunto , Ratos , Comprimidos
8.
Cell Physiol Biochem ; 53(4): 701-712, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31592599

RESUMO

BACKGROUND/AIMS: Cholinergic signalling mediated by the activation of muscarinic and nicotinic receptors has been described in the literature as a classic and important signalling pathway in the regulation of the inflammatory response. Recent research has investigated the role of acetylcholine, the physiological agonist of these receptors, in the control of energy homeostasis at the central level. Studies have shown that mice that do not express acetylcholine in brain regions regulating energy homeostasis present with excessive weight gain and hyperphagia. However, it has not yet been well-described in the literature which cholinergic receptor subunits are involved in this response; moreover, the signalling pathways responsible for the observed effects are not fully delineated. The hypothalamus is the regulating centre of energy homeostasis, and the α7 subunit of the nicotinic acetylcholine receptor (α7nAChR) is highly expressed in this region. When active, α7nAChR recruits proteins such as JAK2/STAT3 to mediate its signalling; the same intracellular components are required by leptin, an anorexigenic hormone. The aim of the present study was to evaluate the role of the hypothalamic α7nAChR in the control of energy homeostasis. METHODS: The work was performed on Swiss male mice. Initially, using immunofluorescent staining on brain sections, the presence of α7nAChR in hypothalamic cells regulating energy homeostasis was evaluated. Animals were submitted to stereotaxis in the lateral ventricle and intracerebroventricular stimulation (ICV) was used for the administration of an agonist (PNU) or antagonist (α-bungarotoxin) of α7nAChR. Metabolic parameters were evaluated and the expression of neuropeptides was evaluated in the hypothalamus by real-time PCR and western blot. The expression of hypothalamic neuropeptides was evaluated in mice treated with siRNA or inhibitors of JAK2/STAT3 (AG490 and STATTIC) proteins. We also evaluated food intake in α7nAChR knockout animals (α7KO). Additionally, in mouse hypothalamic cell culture (the mypHoA-POMC/GFP lineage), we evaluated the expression of neuropeptides and pSTAT3 after stimulation with PNU. RESULTS: Our results indicate co-localisation of α7nAChR with α-MSH, AgRP and NPY in hypothalamic cells. Pharmacological activation of α7nAChR reduced food intake and increased hypothalamic POMC expression and decreased NPY and AgRP mRNA levels and the protein content of pAMPK. Inhibition of α7nAChR with an antagonist increased the mRNA content of NPY and AgRP. Inhibition of α7nAChR with siRNA led to the suppression of POMC expression and an increase in AgRP mRNA levels. α7KO mice showed no changes in food intake. Inhibition of proteins involved in the JAK2/STAT3 signalling pathway reversed the effects observed after PNU stimulation. POMC-GFP cells, when treated with PNU, showed increased POMC expression and nuclear translocation of pSTAT3. CONCLUSION: Thus, selective activation of α7nAChR is able to modulate important markers of the response to food intake, suggesting that α7nAChR activation can suppress the expression of orexigenic markers and favour the expression of anorexics using the intracellular JAK2/STAT3 machinery.


Assuntos
Proteína Relacionada com Agouti/metabolismo , Janus Quinase 2/metabolismo , Pró-Opiomelanocortina/metabolismo , Fator de Transcrição STAT3/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Proteína Relacionada com Agouti/genética , Animais , Benzamidas/farmacologia , Compostos Bicíclicos com Pontes/farmacologia , Bungarotoxinas/farmacologia , Linhagem Celular , Ingestão de Alimentos/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Janus Quinase 2/antagonistas & inibidores , Janus Quinase 2/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/metabolismo , Pró-Opiomelanocortina/genética , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/genética , Transdução de Sinais/efeitos dos fármacos , Receptor Nicotínico de Acetilcolina alfa7/agonistas , Receptor Nicotínico de Acetilcolina alfa7/antagonistas & inibidores , Receptor Nicotínico de Acetilcolina alfa7/genética
9.
Inflammation ; 42(6): 2236-2245, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31522340

RESUMO

The release of inflammatory cytokines and chemokines and autophagy has been reported to be involved in the pathogenic mechanism of acute lung injury (ALI). Reportedly, alpha-7 nicotinic acetylcholine receptors (α7nAchR) might play a protective role in LPS-induced ALI. In the current research, we established LPS-induced ALI model in mice and α7nAchR agonist PNU-282987 improved LPS-induced injury. In MH-S cells, LPS stimulation inhibited, whereas α7nAchR agonist PNU-282987 enhanced the autophagy. α7nAchR agonist PNU-282987 protected MH-S cells from LPS-induced inflammation by reducing the concentrations of IL-6, TNF-α, and IL-1ß. Finally, LPS stimulation dramatically inhibited MH-S cell viability but enhanced cell apoptosis, whereas PNU-282987 treatment exerted opposite effects; α7nAchR might regulate the cellular homeostasis via affecting the crosstalk between the autophagy and apoptosis in MH-S cells; in other words, α7nAChR agonist enhances MH-S cell autophagy and inhibits MH-S cell apoptosis. In conclusion, α7nAchR promote the protective autophagy in LPS-induced ALI model in mice and MH-S cells. The application of α7nAchR agonist is considered a potent target for LPS-induced ALI, which needs further clinical investigation.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Autofagia/efeitos dos fármacos , Receptor Nicotínico de Acetilcolina alfa7/agonistas , Lesão Pulmonar Aguda/induzido quimicamente , Animais , Apoptose/efeitos dos fármacos , Benzamidas/farmacologia , Compostos Bicíclicos com Pontes/farmacologia , Linhagem Celular , Citoproteção/efeitos dos fármacos , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Lipopolissacarídeos , Camundongos
10.
Science ; 365(6451): 393-396, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31346065

RESUMO

The genetic variation of rice cultivars provides a resource for further varietal improvement through breeding. Some rice varieties are sensitive to benzobicyclon (BBC), a ß-triketone herbicide that inhibits 4-hydroxyphenylpyruvate dioxygenase (HPPD). Here we identify a rice gene, HIS1 (HPPD INHIBITOR SENSITIVE 1), that confers resistance to BBC and other ß-triketone herbicides. We show that HIS1 encodes an Fe(II)/2-oxoglutarate-dependent oxygenase that detoxifies ß-triketone herbicides by catalyzing their hydroxylation. Genealogy analysis revealed that BBC-sensitive rice variants inherited a dysfunctional his1 allele from an indica rice variety. Forced expression of HIS1 in Arabidopsis conferred resistance not only to BBC but also to four additional ß-triketone herbicides. HIS1 may prove useful for breeding herbicide-resistant crops.


Assuntos
Compostos Bicíclicos com Pontes/química , Compostos Bicíclicos com Pontes/farmacologia , Genes de Plantas , Resistência a Herbicidas/genética , Oryza/efeitos dos fármacos , Oryza/genética , Oxigenases/genética , Sulfonas/química , Sulfonas/farmacologia , 4-Hidroxifenilpiruvato Dioxigenase/antagonistas & inibidores , Cetonas/química
11.
Org Biomol Chem ; 17(22): 5615-5632, 2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-31120090

RESUMO

Routes to bicyclic tetramates derived from cysteine permitting ready incorporation of functionality at two different points around the periphery of a heterocyclic skeleton are reported. This has enabled the identification of systems active against Gram-positive bacteria, some of which show gyrase and RNA polymerase inhibitory activity. In particular, tetramates substituted with glycosyl side chains, chosen to impart polarity and aqueous solubility, show high antibacterial activity coupled with modest gyrase/polymerase activity in two cases. An analysis of physicochemical properties indicates that the antibacterially active tetramates generally occupy physicochemical space with MW of 300-600, clog D7.4 of -2.5 to 4 and rel. PSA of 11-22%. This work demonstrates that biologically active 3D libraries are readily available by manipulation of a tetramate skeleton.


Assuntos
Antibacterianos/farmacologia , Compostos Bicíclicos com Pontes/farmacologia , Cisteína/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/química , Compostos Bicíclicos com Pontes/síntese química , Compostos Bicíclicos com Pontes/química , Cisteína/química , Testes de Sensibilidade Microbiana , Estrutura Molecular
12.
Invest Ophthalmol Vis Sci ; 60(5): 1353-1361, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30934054

RESUMO

Purpose: Motion detection is performed by a unique neural network in the mouse retina. Starburst amacrine cells (SACs), which release acetylcholine and gamma-aminobutyric acid (GABA) into the network, are key neurons in the motion detection pathway. Although GABA contributions to the network have been extensively studied, the role of acetylcholine is minimally understood. Acetylcholine receptors are present in a subset of bipolar, amacrine, and ganglion cells. We focused on α7-nicotinic acetylcholine receptor (α7-nAChR) expression in bipolar cells, and investigated which types of bipolar cells possess α7-nAChRs. Methods: Retinal slice sections were prepared from C57BL/6J and Gus8.4-GFP mice. Specific expression of α7-nAChRs in bipolar cells was examined using α-bungarotoxin (αBgTx)-conjugated Alexa dyes co-labeled with specific bipolar cell markers. Whole-cell recordings were conducted from bipolar cells in retinal slice sections. A selective α7-nAChR agonist, PNU282987, was applied by a puff and responses were recorded. Results: αBgTx fluorescence was observed primarily in bipolar cell somas. We found that α7-nAChRs were expressed by the majority of type 1, 2, 4, and 7 bipolar cells. Whole-cell recordings revealed that type 2 and 7 bipolar cells depolarized by PNU application. In contrast, α7-nAChRs were not detected in most of type 3, 5, 6, and rod bipolar cells. Conclusions: We found that α7-nAChRs are present in bipolar cells in a type-specific manner. Because these bipolar cells provide synaptic inputs to SACs and direction selective ganglion cells, α7-nAChRs may play a role in direction selectivity by modulating these bipolar cells' outputs.


Assuntos
Células Bipolares da Retina/metabolismo , Transmissão Sináptica/fisiologia , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Animais , Benzamidas/farmacologia , Compostos Bicíclicos com Pontes/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , Percepção de Movimento/fisiologia , Agonistas Nicotínicos/farmacologia , Receptor Nicotínico de Acetilcolina alfa7/antagonistas & inibidores
13.
Molecules ; 24(8)2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31027274

RESUMO

The chemical composition and biological activity of essential oils isolated from the leaves of Siparuna aspera, Siparuna macrotepala, Piper leticianum, Piper augustum and the rhizome of Hedychium coronarium were evaluated. These species are used medicinally in different ways by the Amazonian communities that live near the Kutukú mountain range. Chemical studies revealed that the main components for the two Siparuna species were germacrene D, bicyclogermacrene, α-pinene, δ-cadinene, δ-elemene, α-copaene and ß-caryophyllene; for the two Piper species ß-caryophyllene, germacrene D, α-(E,E)-farnesene, ß-elemene, bicyclogermacrene, δ-cadinene and for H. coronarium 1,8-cineole, ß-pinene, α-pinene and α-terpineol. The antioxidant activity of all essential oils was evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), photochemiluminescence (PCL) quantitative assays, and DPPH and ABTS bioautographic profiles, with different results for each of them. Antimicrobial activity studies were carried out on three yeasts, six Gram positive and four Gram negative bacteria, by means of the disc diffusion method. The essential oil of H. coronarium showed the most relevant results on L. grayi, K. oxytoca and S. mutans, P. augustum and P. leticianum on S. mutans. An antibacterial bioautographic test for H. coronarium was also carried out and highlighted the potential activity of terpinen-4-ol and 1,8-cineole.


Assuntos
Óleos Voláteis/análise , Zingiberaceae/química , Antibacterianos/análise , Antibacterianos/farmacologia , Monoterpenos Bicíclicos , Compostos Bicíclicos com Pontes/análise , Compostos Bicíclicos com Pontes/farmacologia , Monoterpenos Cicloexânicos , Cicloexenos/análise , Cicloexenos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Monoterpenos/análise , Monoterpenos/farmacologia , Óleos Voláteis/farmacologia , Floresta Úmida , Sesquiterpenos/análise , Sesquiterpenos/farmacologia
14.
Pharmazie ; 74(3): 147-149, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30961679

RESUMO

Mirogabalin, which is a novel ligand for the α2δ subunit of voltage-gated calcium channels, is being developed for treating neuropathic pain including diabetic peripheral neuropathy and postherpetic neuralgia. Mirogabalin possesses unique α2δ subunit binding characteristics and has potent and long-lasting analgesic effects in neuropathic pain models. In the present study, we investigated the effects of mirogabalin on N-type calcium channel currents of the rat dorsal root ganglion (DRG) culture neurons using the whole-cell patch clamp technique. Small or medium DRG neurons were isolated from Sprague-Dawley rats and were incubated for 20 to 24 h with mirogabalin or pregabalin. The DRG neurons were depolarised from a holding potential of -40 mV to +40 mV in steps of 10 mV for 220 ms, and elicited N-type calcium channel currents were recorded. The N-type calcium channel currents were verified by sensitivity to ω-conotoxin GVIA, a selective N-type calcium channel blocker. Mirogabalin inhibited the calcium channel currents of rat DRG neurons at 50 µM, and pregabalin inhibited them at 200 µM. Mirogabalin and pregabalin showed significant differences in the peak current densities at depolarisation to -20 and -10 mV when compared with that shown by the vehicle control. In conclusion, mirogabalin inhibits N-type calcium channel currents in rat DRG culture neurons. The potent and long-lasting analgesic effects of mirogabalin are thought to be associated with its potent and selective binding to α2δ-1 subunits and following functional inhibition of calcium channel currents.


Assuntos
Compostos Bicíclicos com Pontes/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio Tipo N/metabolismo , Gânglios Espinais/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Animais , Compostos Bicíclicos com Pontes/química , Bloqueadores dos Canais de Cálcio/química , Células Cultivadas , Conotoxinas/farmacologia , Gânglios Espinais/citologia , Gânglios Espinais/metabolismo , Neurônios/metabolismo , Técnicas de Patch-Clamp , Pregabalina/farmacologia , Ratos , Ratos Sprague-Dawley
15.
Int J Mol Sci ; 20(6)2019 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-30917511

RESUMO

There is an urgent need to develop novel drugs for osteoporosis which occurs due to estrogen deficiency. Phytoestrogens derived from medicinal plants would be the best alternative to chemical drugs with harmful side effects. The main purpose of the present study was to investigate the effect of ferutinin compared to 17ß-estradiol (E2) on bone mineralization of zebrafish larvae. Regarding the lack of publications, the histology analysis was performed after exposure to E2 to find effective treatment on bone mineralization of developing zebrafish larvae. Then, the larvae were exposed to four concentrations of ferutinin at three time points to assess the mortality, the expression of some related genes and histology of the ceratohyal and hyomandibular of treated larvae. The RT-PCR result of the treatment groups demonstrated the similar expression pattern in the larvae which were exposed to 1.25 µg/mL of ferutinin and 2 µM of E2 at 2 dpf, which confirmed the result of histology analysis. In addition, RT-qPCR of high concentration of ferutinin and E2 demonstrated that bmp2a/b and esr1 were downregulated and upregulated when the larvae were exposed to 5 µg/mL of ferutinin and 10 µM of E2, respectively.


Assuntos
Benzoatos/farmacologia , Calcificação Fisiológica/efeitos dos fármacos , Cicloeptanos/farmacologia , Estradiol/farmacologia , Estrogênios/farmacologia , Sesquiterpenos/farmacologia , Animais , Proteína Morfogenética Óssea 2/genética , Proteína Morfogenética Óssea 2/metabolismo , Compostos Bicíclicos com Pontes/farmacologia , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Larva/efeitos dos fármacos , Larva/metabolismo , Peixe-Zebra , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
16.
Pharmacol Biochem Behav ; 180: 32-43, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30904543

RESUMO

Serotonin 5-HT2A receptors are expressed throughout the mesolimbic and mesocortical dopamine pathways, and manipulation of this receptor system has a profound impact on dopamine functions and dopamine-mediated behaviors. It is highly likely that 5-HT2A receptors may also modulate the D2-mediated maternal effects. The present study investigated this issue and also explored the possible behavioral mechanisms. We tested the effects of two D2 drugs (an agonist quinpirole: 0.5, 1.0 mg/kg, and a potent D2 antagonist haloperidol: 0.05, 0.10 mg/kg, sc) and their combinations with two 5-HT2A drugs (a selective 5-HT2A agonist TCB-2: 2.5 mg/kg, and 5-HT2A antagonist MDL100907, 1.0 mg/kg, sc) on maternal behavior in Sprague-Dawley postpartum females. Individually, TCB-2 (2.5 mg/kg, sc) and quinpirole (0.5 and 1.0 mg/kg, sc) reduced pup preference and disrupted home-cage maternal behavior. In contrast, haloperidol (0.10 mg/kg, sc) only disrupted home-cage maternal behavior, but did not suppress pup preference. MDL100907 (1.0 mg/kg, sc) by itself had no effect on either pup preference or maternal behavior. When administered in combination, pretreatment of TCB-2 did not alter quinpirole's disruption of pup preference and home-cage maternal behavior (possibly due to the floor effect), however, it did enhance haloperidol's disruption of pup retrieval in the home cage. MDL100907 had no effect both quinpirole's and haloperidol's disruption of pup preference and home-cage maternal behavior. Interestingly, haloperidol attenuated TCB-2's disruptive effect on pup preference. These findings suggest that activation of 5-HT2A receptors tends to enhance D2-mediated maternal disruption, whereas blockade of 5-HT2A receptors is less effective. They also suggest that 5-HT2A receptors may have a direct effect on maternal behavior independent of their interaction with D2 receptors. The possible behavioral and neural mechanisms by which 5-HT2A- and D2-mediated maternal effects and their interaction are discussed.


Assuntos
Comportamento Materno/fisiologia , Receptor 5-HT2A de Serotonina/metabolismo , Receptores de Dopamina D2/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Compostos Bicíclicos com Pontes/administração & dosagem , Compostos Bicíclicos com Pontes/farmacologia , Agonistas de Dopamina/administração & dosagem , Agonistas de Dopamina/farmacologia , Antagonistas dos Receptores de Dopamina D2/administração & dosagem , Antagonistas dos Receptores de Dopamina D2/farmacologia , Feminino , Fluorbenzenos/administração & dosagem , Fluorbenzenos/farmacologia , Haloperidol/administração & dosagem , Haloperidol/farmacologia , Masculino , Comportamento Materno/efeitos dos fármacos , Metilaminas/administração & dosagem , Metilaminas/farmacologia , Piperidinas/administração & dosagem , Piperidinas/farmacologia , Quimpirol/administração & dosagem , Quimpirol/farmacologia , Ratos , Ratos Sprague-Dawley , Agonistas do Receptor 5-HT2 de Serotonina/administração & dosagem , Agonistas do Receptor 5-HT2 de Serotonina/farmacologia , Antagonistas do Receptor 5-HT2 de Serotonina/administração & dosagem , Antagonistas do Receptor 5-HT2 de Serotonina/farmacologia
17.
Mol Med Rep ; 19(5): 3791-3798, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30864715

RESUMO

The cholinergic anti­inflammatory pathway is considered an attractive approach for the alleviation of inflammatory diseases. Sepsis is characterized by systemic inflammation and widespread organ injury, especially that in the lung. In the present study, we explored the effects of an α7nAChR agonist, PNU­282987, on sepsis­induced lung injury and investigated the mechanisms of PNU­282987 in response to lipopolysaccharide (LPS) stimulation in peritoneal macrophages. Sepsis was induced in C57BL/6 mice via cecal ligation puncture (CLP). Fifty mice were randomly divided into five groups: The sham group treated with vehicle, the sham group treated with PNU­282987, the CLP group treated with vehicle, and the CLP group treated with PNU­282987 (1 mg/kg) 1 h before or 2 h after surgery. All mice were sacrificed at 12 or 24 h after CLP. Both pre­ and post­CLP treatment with PNU­282987 significantly attenuated sepsis­induced lung injury and the release of IL­6 in the bronchoalveolar lavage fluid (BALF). Pre­treatment with PNU­282987 also inhibited sepsis­increased TNF­α and IL­6 production, while post­CLP treatment only inhibited IL­6 production in the lung tissue. Neither pre­ nor post­CLP treatment with PNU­282987 affected IL­6 release in the serum. Furthermore, pretreatment with PNU­282987 resulted in reductions in TNF­α and IL­6 release in a dose­ and time­dependent manner and decreased the phosphorylation levels of p38, JNK and ERK under LPS conditions in peritoneal macrophages. Our results demonstrate that activation of α7nAChR alleviates sepsis­induced lung injury; this effect is associated with the suppression of inflammatory responses via the MAPK pathway, suggesting that α7nAChR is a potential therapeutic target for the treatment of sepsis.


Assuntos
Lesão Pulmonar Aguda/prevenção & controle , Benzamidas/farmacologia , Compostos Bicíclicos com Pontes/farmacologia , Modelos Animais de Doenças , Macrófagos Peritoneais/efeitos dos fármacos , Sepse/complicações , Lesão Pulmonar Aguda/etiologia , Lesão Pulmonar Aguda/patologia , Animais , Células Cultivadas , Lipopolissacarídeos/farmacologia , Macrófagos Peritoneais/metabolismo , Macrófagos Peritoneais/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
18.
Artigo em Inglês | MEDLINE | ID: mdl-30782985

RESUMO

Zidebactam and WCK 5153 are novel bicyclo-acyl hydrazide (BCH) agents that have previously been shown to act as ß-lactam enhancer (BLE) antibiotics in Pseudomonas aeruginosa and Acinetobacter baumannii The objectives of this work were to identify the molecular targets of these BCHs in Klebsiella pneumoniae and to investigate their potential BLE activity for cefepime and aztreonam against metallo-ß-lactamase (MBL)-producing strains in vitro and in vivo Penicillin binding protein (PBP) binding profiles were determined by Bocillin FL assay, and 50% inhibitory concentrations (IC50s) were determined using ImageQuant TL software. MICs and kill kinetics for zidebactam, WCK 5153, and cefepime or aztreonam, alone and in combination, were determined against clinical K. pneumoniae isolates producing MBLs VIM-1 or NDM-1 (plus ESBLs and class C ß-lactamases) to assess the in vitro enhancer effect of BCH compounds in conjunction with ß-lactams. Additionally, murine systemic and thigh infection studies were conducted to evaluate BLE effects in vivo Zidebactam and WCK 5153 showed specific, high PBP2 affinity in K. pneumoniae The MICs of BLEs were >64 µg/ml for all MBL-producing strains. Time-kill studies showed that a combination of these BLEs with either cefepime or aztreonam provided 1 to >3 log10 kill against MBL-producing K. pneumoniae strains. Furthermore, the bactericidal synergy observed for these BLE-ß-lactam combinations translated well into in vivo efficacy even in the absence of MBL inhibition by BLEs, a characteristic feature of the ß-lactam enhancer mechanism of action. Zidebactam and WCK 5153 are potent PBP2 inhibitors and display in vitro and in vivo BLE effects against multidrug-resistant (MDR) K. pneumoniae clinical isolates producing MBLs.


Assuntos
Compostos Azabicíclicos/farmacologia , Compostos Bicíclicos com Pontes/farmacologia , Ciclo-Octanos/farmacologia , Octanos/farmacologia , Piperidinas/farmacologia , beta-Lactamas/farmacologia , Klebsiella pneumoniae/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Proteínas de Ligação às Penicilinas/genética , Proteínas de Ligação às Penicilinas/metabolismo
19.
Naunyn Schmiedebergs Arch Pharmacol ; 392(6): 723-728, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30770951

RESUMO

Mirogabalin, a novel ligand for the α2δ subunit of voltage-gated calcium channels, is under the development for the treatment of neuropathic pain. Mirogabalin specifically and potently binds to α2δ subunits, and it shows analgesic effects in both peripheral and central neuropathic pain models in rats. To expand pharmacological findings on mirogabalin and provide additional information of its potential for chronic pain therapy, we examined the effects of mirogabalin in 2 experimental models of fibromyalgia, namely, the intermittent cold stress model (ICS model) and the unilateral intramuscular acidic saline injection model (Sluka model). To induce chronic mechanical hypersensitivity, mice were placed under ICS conditions for 3 days, whereas rats were injected twice with acidic saline (pH 4) into the gastrocnemius muscle in a 4-day interval. The pain sensitivity was evaluated by the von Frey test. Long-lasting increases in pain response score or decreases in pain threshold to the von Frey stimulation were observed in both the ICS and Sluka models. Mirogabalin (1, 3, or 10 mg/kg, p.o.) dose-dependently alleviated the mechanical hypersensitivity, with significant effects persisting at 6 or 8 h following administration. The standard α2δ ligand, pregabalin (30 mg/kg, p.o.), also significantly reduced the mechanical hypersensitivity. In summary, mirogabalin showed analgesic effects in the ICS model mice and in the Sluka model rats. Therefore, mirogabalin may have the potential to provide effective pain relief in patients with fibromyalgia.


Assuntos
Analgésicos/farmacologia , Compostos Bicíclicos com Pontes/farmacologia , Canais de Cálcio/fisiologia , Fibromialgia/tratamento farmacológico , Neuralgia/tratamento farmacológico , Animais , Compostos Bicíclicos com Pontes/uso terapêutico , Modelos Animais de Doenças , Feminino , Ligantes , Masculino , Camundongos , Limiar da Dor/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
20.
Invest Ophthalmol Vis Sci ; 60(2): 570-579, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30721274

RESUMO

Purpose: The adult mammalian retina is typically incapable of regeneration when damaged by disease or trauma. Restoration of function would require generation of new adult neurons, something that until recently, mammals were thought to be incapable of doing. However, previous studies from this laboratory have shown that the α7 nicotinic acetylcholine receptor (α7 nAChR) agonist, PNU-282987, induces cell cycle reentry of Müller glia and generation of mature retinal neurons in adult rats, in the absence of detectible injury. This study analyzes how PNU-282987 treatment in RPE leads to robust BrdU incorporation in Müller glia in adult mice and leads to generation of Müller-derived retinal progenitors and neuronal differentiation. Methods: Retinal BrdU incorporation was examined after eye drop application of PNU-282987 in adult wild-type and transgenic mice that contain tamoxifen-inducible tdTomato Müller glia, or after intraocular injection of conditioned medium from PNU-282987-treated cultured RPE cells. Results: PNU-282987 induced robust incorporation of BrdU in all layers of the adult mouse retina. The α7 nAChR agonist was found to stimulate cell cycle reentry of Müller glia and their generation of new retinal progenitors indirectly, via the RPE, in an α7 nAChR-dependent fashion. Conclusions: The results from this study point to RPE as a contributor to Müller glial neurogenic responses. The manipulation of the RPE to stimulate retinal neurogenesis offers a new direction for developing novel and potentially transformative treatments to reverse the loss of neurons associated with neurodegenerative disease, traumatic injury, or aging.


Assuntos
Benzamidas/farmacologia , Compostos Bicíclicos com Pontes/farmacologia , Células Ependimogliais/fisiologia , Neurogênese/fisiologia , Neuroglia/fisiologia , Agonistas Nicotínicos/farmacologia , Epitélio Pigmentado da Retina/efeitos dos fármacos , Receptor Nicotínico de Acetilcolina alfa7/agonistas , Animais , Bromodesoxiuridina/metabolismo , Ciclo Celular/fisiologia , Células Cultivadas , Células Ependimogliais/citologia , Feminino , Masculino , Camundongos , Camundongos Transgênicos , Fator de Transcrição PAX6/metabolismo , Ratos , Epitélio Pigmentado da Retina/citologia , Epitélio Pigmentado da Retina/metabolismo , Células-Tronco/fisiologia
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