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1.
Plant Biotechnol J ; 22(4): 929-945, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38009862

RESUMO

The control of flowering time in maize is crucial for reproductive success and yield, and it can be influenced by environmental stresses. Using the approaches of Ac/Ds transposon and transposable element amplicon sequencing techniques, we identified a Ds insertion mutant in the ZmPRR37 gene. The Ds insertion showed a significant correlation with days to anthesis. Further research indicated that ZmPRR37-CR knockout mutants exhibited early flowering, whereas ZmPRR37-overexpression lines displayed delayed flowering compared to WT under long-day (LD) conditions. We demonstrated that ZmPRR37 repressed the expression of ZmNF-YC2 and ZmNF-YA3 to delay flowering. Association analysis revealed a significant correlation between flowering time and a SNP2071-C/T located upstream of ZmPRR37. The SNP2071-C/T impacted the binding capacity of ZmELF6 to the promoter of ZmPRR37. ZmELF6 also acted as a flowering suppressor in maize under LD conditions. Notably, our study unveiled that ZmPRR37 can enhance salt stress tolerance in maize by directly regulating the expression of ABA-responsive gene ZmDhn1. ZmDhn1 negatively regulated maize salt stress resistance. In summary, our findings proposed a novel pathway for regulating photoperiodic flowering and responding to salt stress based on ZmPRR37 in maize, providing novel insights into the integration of abiotic stress signals into floral pathways.


Assuntos
Flores , Proteínas de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Flores/fisiologia , Zea mays/genética , Zea mays/metabolismo , Fotoperíodo , Regiões Promotoras Genéticas , Regulação da Expressão Gênica de Plantas/genética
2.
J Biol Phys ; 49(4): 463-482, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37572243

RESUMO

Excessive neural synchronization of neural populations in the beta (ß) frequency range (12-35 Hz) is intimately related to the symptoms of hypokinesia in Parkinson's disease (PD). Studies have shown that delayed feedback stimulation strategies can interrupt excessive neural synchronization and effectively alleviate symptoms associated with PD dyskinesia. Work on optimizing delayed feedback algorithms continues to progress, yet it remains challenging to further improve the inhibitory effect with reduced energy expenditure. Therefore, we first established a neural mass model of the cortex-basal ganglia-thalamus-pedunculopontine nucleus (CBGTh-PPN) closed-loop system, which can reflect the internal properties of cortical and basal ganglia neurons and their intrinsic connections with thalamic and pedunculopontine nucleus neurons. Second, the inhibitory effects of three delayed feedback schemes based on the external globus pallidum (GPe) on ß oscillations were investigated separately and compared with those based on the subthalamic nucleus (STN) only. Our results show that all four delayed feedback schemes achieve effective suppression of pathological ß oscillations when using the linear delayed feedback algorithm. The comparison revealed that the three GPe-based delayed feedback stimulation strategies were able to have a greater range of oscillation suppression with reduced energy consumption, thus improving control performance effectively, suggesting that they may be more effective for the relief of Parkinson's motor symptoms in practical applications.


Assuntos
Doença de Parkinson , Núcleo Subtalâmico , Humanos , Retroalimentação , Gânglios da Base/patologia , Gânglios da Base/fisiologia , Tálamo/patologia , Tálamo/fisiologia , Núcleo Subtalâmico/patologia , Núcleo Subtalâmico/fisiologia , Doença de Parkinson/patologia
3.
J Pharmacol Exp Ther ; 374(3): 462-468, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32561684

RESUMO

Attenuating emesis elicited by both disease and medical treatments of disease remains a critical public health challenge. Although cannabinergic medications have been used in certain treatment-resistant populations, Food and Drug Administration-approved cannabinoid antiemetics are associated with undesirable side effects, including cognitive disruption, that limit their prescription. Previous studies have shown that a metabolically stable analog of the endocannabinoid anandamide, methanandamide (mAEA), may produce lesser cognitive disruption than that associated with the primary psychoactive constituent in cannabis, Δ9-tetrahydrocannabinol (Δ9-THC), raising the possibility that endocannabinoids may offer a therapeutic advantage over currently used medications. The present studies were conducted to evaluate this possibility by comparing the antiemetic effects of Δ9-THC (0.032-0.1 mg/kg) and mAEA (3.2-10.0 mg/kg) against nicotine- and lithium chloride (LiCl)-induced emesis and prodromal hypersalivation in squirrel monkeys. Pretreatment with 0.1 mg/kg Δ9-THC blocked nicotine-induced emesis and reduced hypersalivation in all subjects and blocked LiCl-induced emesis and reduced hypersalivation in three of four subjects. Pretreatment with 10 mg/kg mAEA blocked nicotine-induced emesis in three of four subjects and LiCl-induced emesis in one of four subjects and reduced both nicotine- and LiCl-induced hypersalivation. Antiemetic effects of Δ9-THC and mAEA were reversed by rimonabant pretreatment, providing verification of cannabinoid receptor type 1 mediation. These studies systematically demonstrate for the first time the antiemetic effects of cannabinoid agonists in nonhuman primates. Importantly, although Δ9-THC produced superior antiemetic effects, the milder cognitive effects of mAEA demonstrated in previous studies suggest that it may provide a favorable treatment option under clinical circumstances in which antiemetic efficacy must be balanced against side effect liability. SIGNIFICANCE STATEMENT: Emesis has significant evolutionary value as a defense mechanism against ingested toxins; however, it is also one of the most common adverse symptoms associated with both disease and medical treatments of disease. The development of improved antiemetic pharmacotherapies has been impeded by a paucity of animal models. The present studies systematically demonstrate for the first time the antiemetic effects of the phytocannabinoid Δ9-tetrahydrocannabinol and endocannabinoid analog methanandamide in nonhuman primates.


Assuntos
Antieméticos/farmacologia , Agonistas de Receptores de Canabinoides/farmacologia , Animais , Antieméticos/uso terapêutico , Ácidos Araquidônicos/farmacologia , Ácidos Araquidônicos/uso terapêutico , Agonistas de Receptores de Canabinoides/uso terapêutico , Dronabinol/farmacologia , Dronabinol/uso terapêutico , Interações Medicamentosas , Masculino , Receptor CB1 de Canabinoide/agonistas , Saimiri , Salivação/efeitos dos fármacos , Vômito/tratamento farmacológico
4.
Molecules ; 25(3)2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32041131

RESUMO

A new approach to synthesize cannabilactones using Suzuki cross-coupling reaction followed by one-step demethylation-cyclization is presented. The two key cannabilactone prototypes AM1710 and AM1714 were obtained selectively in high overall yields and in a lesser number of synthetic steps when compared to our earlier synthesis. The new approach expedited the synthesis of cannabilactone analogs with structural modifications at the four potential pharmacophoric regions.


Assuntos
Canabinoides/síntese química , Cromonas/síntese química
5.
Mol Pharmacol ; 95(2): 155-168, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30504240

RESUMO

AM1710 (3-(1,1-dimethyl-heptyl)-1-hydroxy-9-methoxy-benzo(c) chromen-6-one), a cannabilactone cannabinoid receptor 2 (CB2) agonist, suppresses chemotherapy-induced neuropathic pain in rodents without producing tolerance or unwanted side effects associated with CB1 receptors; however, the signaling profile of AM1710 remains incompletely characterized. It is not known whether AM1710 behaves as a broad-spectrum analgesic and/or suppresses the development of opioid tolerance and physical dependence. In vitro, AM1710 inhibited forskolin-stimulated cAMP production and produced enduring activation of extracellular signal-regulated kinases 1/2 phosphorylation in human embryonic kidney (HEK) cells stably expressing mCB2. Only modest species differences in the signaling profile of AM1710 were observed between HEK cells stably expressing mCB2 and hCB2. In vivo, AM1710 produced a sustained inhibition of paclitaxel-induced allodynia in mice. In paclitaxel-treated mice, a history of AM1710 treatment (5 mg/kg per day × 12 day, i.p.) delayed the development of antinociceptive tolerance to morphine and attenuated morphine-induced physical dependence. AM1710 (10 mg/kg, i.p.) did not precipitate CB1 receptor-mediated withdrawal in mice rendered tolerant to Δ9-tetrahydrocannabinol, suggesting that AM1710 is not a functional CB1 antagonist in vivo. Furthermore, AM1710 (1, 3, 10 mg/kg, i.p.) did not suppress established mechanical allodynia induced by complete Freund's adjuvant (CFA) or by partial sciatic nerve ligation (PSNL). Similarly, prophylactic and chronic dosing with AM1710 (10 mg/kg, i.p.) did not produce antiallodynic efficacy in the CFA model. By contrast, gabapentin suppressed allodynia in both CFA and PSNL models. Our results indicate that AM1710 is not a broad-spectrum analgesic agent in mice and suggest the need to identify signaling pathways underlying CB2 therapeutic efficacy to identify appropriate indications for clinical translation.


Assuntos
Cromonas/farmacologia , Tolerância a Medicamentos/fisiologia , Morfina/farmacologia , Neuralgia/tratamento farmacológico , Receptor CB2 de Canabinoide/agonistas , Analgésicos Opioides/farmacologia , Animais , Canabinoides/metabolismo , Linhagem Celular , Dronabinol/farmacologia , Células HEK293 , Humanos , Hiperalgesia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neuralgia/metabolismo , Paclitaxel/farmacologia , Receptor CB1 de Canabinoide/metabolismo , Receptor CB2 de Canabinoide/metabolismo , Transdução de Sinais/efeitos dos fármacos
6.
J Pharmacol Exp Ther ; 363(3): 314-323, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28947487

RESUMO

An improved understanding of the endocannabinoid system has provided new avenues of drug discovery and development toward the management of pain and other behavioral maladies. Exogenous cannabinoid type 1 (CB1) receptor agonists such as Δ9-tetrahydrocannabinol are increasingly used for their medicinal actions; however, their utility is constrained by concern regarding abuse-related subjective effects. This has led to growing interest in the clinical benefit of indirectly enhancing the activity of the highly labile endocannabinoids N-arachidonoylethanolamine [AEA (or anandamide)] and/or 2-arachidonoylglycerol (2-AG) via catabolic enzyme inhibition. The present studies were conducted to determine whether such actions can lead to CB1 agonist-like subjective effects, as reflected in CB1-related discriminative stimulus effects in laboratory subjects. Squirrel monkeys (n = 8) that discriminated the CB1 full agonist AM4054 (0.01 mg/kg) from vehicle were used to study, first, the inhibitors of fatty acid amide hydrolase (FAAH) or monoacylglycerol lipase (MGL) alone or in combination [FAAH (URB597, AM4303); MGL (AM4301); FAAH/MGL (JZL195, AM4302)] and, second, the ability of the endocannabinoids AEA and 2-AG to produce CB1 agonist-like effects when administered alone or after enzyme inhibition. Results indicate that CB1-related discriminative stimulus effects were produced by combined, but not selective, inhibition of FAAH and MGL, and that these effects were nonsurmountably antagonized by low doses of rimonabant. Additionally, FAAH or MGL inhibition revealed CB1-like subjective effects produced by AEA but not by 2-AG. Taken together, the present data suggest that therapeutic effects of combined, but not selective, enhancement of AEA or 2-AG activity via enzyme inhibition may be accompanied by CB1 receptor-mediated subjective effects.


Assuntos
Amidoidrolases/antagonistas & inibidores , Aprendizagem por Discriminação/efeitos dos fármacos , Drogas em Investigação/farmacologia , Endocanabinoides/farmacologia , Inibidores Enzimáticos/farmacologia , Monoacilglicerol Lipases/antagonistas & inibidores , Receptor CB1 de Canabinoide/agonistas , Adamantano/administração & dosagem , Adamantano/efeitos adversos , Adamantano/análogos & derivados , Adamantano/farmacologia , Amidoidrolases/metabolismo , Animais , Ácidos Araquidônicos/administração & dosagem , Ácidos Araquidônicos/agonistas , Ácidos Araquidônicos/antagonistas & inibidores , Ácidos Araquidônicos/farmacologia , Comportamento Animal/efeitos dos fármacos , Antagonistas de Receptores de Canabinoides/administração & dosagem , Antagonistas de Receptores de Canabinoides/efeitos adversos , Antagonistas de Receptores de Canabinoides/farmacologia , Canabinol/administração & dosagem , Canabinol/efeitos adversos , Canabinol/análogos & derivados , Canabinol/farmacologia , Relação Dose-Resposta a Droga , Agonismo de Drogas , Antagonismo de Drogas , Drogas em Investigação/administração & dosagem , Drogas em Investigação/efeitos adversos , Endocanabinoides/administração & dosagem , Endocanabinoides/agonistas , Endocanabinoides/antagonistas & inibidores , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/efeitos adversos , Glicerídeos/administração & dosagem , Glicerídeos/agonistas , Glicerídeos/antagonistas & inibidores , Glicerídeos/farmacologia , Injeções Intramusculares , Injeções Intravenosas , Ligantes , Masculino , Monoacilglicerol Lipases/metabolismo , Proteínas do Tecido Nervoso/agonistas , Proteínas do Tecido Nervoso/antagonistas & inibidores , Proteínas do Tecido Nervoso/metabolismo , Alcamidas Poli-Insaturadas , Receptor CB1 de Canabinoide/antagonistas & inibidores , Receptor CB1 de Canabinoide/metabolismo , Saimiri
7.
RSC Med Chem ; 15(2): 607-611, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38389883

RESUMO

Sulfonyl fluoride EM12-SF was developed previously to covalently engage a histidine residue in the sensor loop of cereblon (CRBN) in the E3 ubiquitin ligase complex CRL4CRBN. Here, we further develop the structure-activity relationships of additional sulfonyl fluoride containing ligands that possess a range of cereblon binding potencies in cells. Isoindoline EM364-SF, which lacks a key hydrogen bond acceptor present in CRBN molecular glues, was identified as a potent binder of CRBN. This led to the development of the reversible molecular glue CPD-2743, that retained cell-based binding affinity for CRBN and degraded the neosubstrate IKZF1 to the same extent as EM12, but unlike isoindolinones, lacked SALL4 degradation activity (a target linked to teratogenicity). CPD-2743 had high permeability and lacked efflux in Caco-2 cells, in contrast to the isoindolinone iberdomide. Our methodology expands the repertoire of sulfonyl exchange chemical biology via the advancement of medicinal chemistry design strategies.

8.
ACS Med Chem Lett ; 15(6): 965-971, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38894922

RESUMO

2-Arachidonoyl glycerol (2-AG) is the principal endogenously produced ligand for the cannabinoid CB1 and CB2 receptors (CBRs). The lack of potent and efficacious 2-AG ligands with resistance against metabolizing enzymes represents a significant void in the armamentarium of research tools available for studying eCB system molecular constituents and their function. Herein we report the first endocannabinoid glyceride templates with remarkably high potency and efficacy at CBRs. Two of our lead chiral 2-AG analogs, namely, (13S)- and (13R)-Me-2-AGs, potently inhibit excitatory neurotransmission via CB1 while they are endowed with excellent resistance to the oxidizing enzyme COX-2. Our SAR results are supported by docking studies of the key analog and 2-AG on the crystal structures of CB1.

9.
Ophthalmology ; 120(11): 2176-83, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23714323

RESUMO

OBJECTIVE: To define the prevalence of blindness and visual impairment (VI) in people in rural Hainan using the rapid assessment of avoidable blindness (RAAB) and to report the outcomes of cataract surgery among the residents. DESIGN: Population-based, cross-sectional survey. PARTICIPANTS: A total of 6482 rural residents of the Hainan province. METHODS: A total of 136 clusters, each of which consisted of 50 people aged ≥50 years, were selected through probability-proportionate-to-size sampling. Door-to-door visits were performed by 2 outreach teams. Visual acuity (VA) was measured on site, and those with VA <6/18 in either eye were examined by an ophthalmologist. Causes of blindness and VI were determined. The causes of poor visual outcome after cataract surgery were evaluated. Information regarding barriers to receiving surgery was collected by trained interviewers. MAIN OUTCOME MEASURES: Prevalence and causes of blindness (VA <3/60), severe VI (SVI) (VA <6/60 but ≥3/60), and VI (VA <6/18 but ≥6/60) based on presenting VA (PVA) were assessed. Outcomes of cataract surgery performed in public and private hospitals and charitable organizations were compared. RESULTS: A total of 6482 subjects were examined (response rate, 95.3%). The sample prevalence of blindness was 4.4% (95% confidence interval [CI], 2.0-6.8). The prevalence of SVI and VI was 1.9% (95% CI, 0-4.3) and 9.9% (95% CI, 7.6-12.2), respectively. Age and sex were associated with increased prevalence of blindness, SVI, and VI. Overall, cataract accounted for approximately 60% of blindness and SVI. Of the 524 eyes that had received cataract surgery, 87.2% had intraocular lenses implanted, 21% had a poor visual outcome (PVA <6 /60), and 20% had a borderline visual outcome (PVA <6/18 but ≥6/60). Eyes that received surgery in charitable organizations had a higher rate of intraocular lens implantation and good visual outcome (VA ≥6/18) compared with eyes that were operated on elsewhere. CONCLUSIONS: The prevalence of blindness, SVI, and VI was high among rural residents in Hainan. Cataract remained the leading cause of avoidable blindness. Outcomes of cataract surgery performed in public hospitals were suboptimal. Quality-control initiatives should be introduced to improve cataract surgery outcomes.


Assuntos
Cegueira/epidemiologia , Extração de Catarata/estatística & dados numéricos , Catarata/epidemiologia , População Rural/estatística & dados numéricos , Baixa Visão/epidemiologia , Pessoas com Deficiência Visual/estatística & dados numéricos , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Estudos Transversais , Feminino , Hospitais Privados/estatística & dados numéricos , Hospitais Públicos/estatística & dados numéricos , Humanos , Implante de Lente Intraocular/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Prevalência , Distribuição por Sexo , Resultado do Tratamento , Acuidade Visual/fisiologia
10.
Brain Behav ; 13(10): e3183, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37533306

RESUMO

BACKGROUND: The role of delayed feedback stimulation in the discussion of Parkinson's disease (PD) has recently received increasing attention. Stimulation of pedunculopontine nucleus (PPN) is an emerging treatment for PD. However, the effect of PPN in regulating PD is ignored, and the delayed feedback stimulation algorithm is facing some problems in parameter selection. METHODS: On the basis of a neural mass model, we established a new network for PPN. Four types of delayed feedback stimulation schemes were designed, such as stimulating subthalamic nucleus (STN) with the local field potentials (LFPs) of STN nucleus, globus pallidus (GPe) with the LFPs of Gpe nucleus, PPN with the LFPs of Gpe nucleus, and STN with the LFPs of PPN nucleus. RESULTS: In this study, we found that all four kinds of delayed feedback schemes are effective, suggesting that the algorithm is simple and more effective in experiments. More specifically, the other three control schemes improved the control performance and reduced the stimulation energy expenditure compared with traditional stimulating STN itself only. CONCLUSION: PPN stimulation can affect the new network and help to suppress pathological oscillations for each neuron. We hope that our results can gain an insight into the future clinical treatment.

11.
ACS Chem Biol ; 18(4): 933-941, 2023 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-37018062

RESUMO

The ability to rapidly and selectively modulate cellular protein levels using small molecules is essential for studying complex biological systems. Degradation tags, such as dTAG, allow for selective protein removal with a specific degrader molecule, but their utility is limited by the large tag size (>12 kDa) and the low efficiency of fusion product gene knock-in. Here, we describe the development of a short 24 amino acid peptide tag that enables cell-based quantification and covalent functionalization of proteins to which it is fused. The minimalistic peptide, termed HiBiT-SpyTag, incorporates the HiBiT peptide for protein level quantification and SpyTag, which forms a spontaneous isopeptide bond in the presence of the SpyCatcher protein. Transient expression of dTAG-SpyCatcher efficiently labels HiBiT-SpyTag-modified BRD4 or IRE1α in cells, and subsequent treatment with the dTAG13 degrader results in efficient protein removal without the need for full dTAG knock-in. We also demonstrate the utility of HiBiT-SpyTag for validating the degradation of the endoplasmic reticulum (ER) stress sensor IRE1α, which led to the development of the first PROTAC degrader of the protein. Our modular HiBiT-SpyTag system represents a valuable tool for the efficient development of degraders and for studying other proximity-induced pharmacology.


Assuntos
Cromatografia de Afinidade , Sondas Moleculares , Peptídeos , Proteólise , Endorribonucleases , Proteínas Nucleares , Peptídeos/química , Proteínas Serina-Treonina Quinases , Fatores de Transcrição , Sondas Moleculares/química , Sondas Moleculares/metabolismo , Quimera de Direcionamento de Proteólise/química , Quimera de Direcionamento de Proteólise/metabolismo , Cromatografia de Afinidade/métodos
12.
ACS Med Chem Lett ; 14(11): 1576-1581, 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37974938

RESUMO

Site-specific modification of amino acid residues in protein binding pockets using sulfonyl exchange chemistry expands the druggable proteome by enabling the development of covalent modulators that target residues beyond cysteine. Sulfonyl fluoride and triazole electrophiles were incorporated previously into the cereblon (CRBN) molecular glue degrader EM12, to covalently engage His353 within the CRBN sensor loop, but these probes had poor human plasma stability. Attenuation of intrinsic reactivity through the development of sulfonyl pyrazoles, imidazoles, and nucleobases enhanced plasma stability, and several compounds retained efficient labeling of His353. For example, sulfonyl imidazole EM12-SO2Im covalently blocked the CRBN binding site and possessed excellent metabolic stability in human plasma, liver microsomes, and hepatocytes. These results highlight the potential suitability of sulfonyl imidazole and related sulfur(VI)-diazole exchange (SuDEx) warheads for covalent drug development and further exemplify the therapeutic promise of site-specific histidine targeting.

13.
J Med Chem ; 66(8): 5524-5535, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-37036171

RESUMO

Heterobifunctional degraders, known as proteolysis targeting chimeras (PROTACs), theoretically possess a catalytic mode-of-action, yet few studies have either confirmed or exploited this potential advantage of event-driven pharmacology. Degraders of oncogenic EML4-ALK fusions were developed by conjugating ALK inhibitors to cereblon ligands. Simultaneous optimization of pharmacology and compound properties using ternary complex modeling and physicochemical considerations yielded multiple catalytic degraders that were more resilient to clinically relevant ATP-binding site mutations than kinase inhibitor drugs. Our strategy culminated in the design of the orally bioavailable derivative CPD-1224 that avoided hemolysis (a feature of detergent-like PROTACs), degraded the otherwise recalcitrant mutant L1196M/G1202R in vivo, and commensurately slowed tumor growth, while the third generation ALK inhibitor drug lorlatinib had no effect. These results validate our original therapeutic hypothesis by exemplifying opportunities for catalytic degraders to proactively address binding site resistant mutations in cancer.


Assuntos
Antineoplásicos , Neoplasias Pulmonares , Humanos , Quinase do Linfoma Anaplásico , Antineoplásicos/farmacologia , Receptores Proteína Tirosina Quinases , Neoplasias Pulmonares/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Mutação , Resistencia a Medicamentos Antineoplásicos , Proteínas de Fusão Oncogênica/genética
14.
Cannabis Cannabinoid Res ; 7(5): 621-627, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-34935460

RESUMO

Introduction: Cannabis acceptance and use continues to rise despite the gaps in knowledge regarding the mechanisms of cannabinoids and the endocannabinoid system in many physiological functions, including respiratory influence. Methods: With recent evidence of cannabinoid receptor 1 (CB1R) presence in the collection of respiratory neurons in the brainstem, as well as in the peripheral lung tissue, it is vital that the mechanisms involved in central and peripheral CB1R modulation of respiratory function be delineated. In this study we sought to define the roles of central versus peripheral CB1R activation on respiratory depression alone and in combination with morphine using whole body plethysmography. Results: We show that the peripherally restricted CB1 agonist (4-{2-[-(1E)-1[(4-propylnaphthalen-1-yl)methylidene]-1H-inden-3yl]ethyl}morpholine [PrNMI] 0.3, 0.6, and 1 mg/kg) does not induce respiratory depression, while our previous studies showed that a central penetrating synthetic cannabinoid does induce respiratory depression. Significantly, the combination of morphine with the peripheral CB1 agonist, PrNMI, attenuated morphine-induced respiratory depression. Conclusions: These studies support that a peripherally restricted CB1R agonist may be a unique strategy to attenuate the respiratory depression associated with opioid therapy.


Assuntos
Canabinoides , Insuficiência Respiratória , Humanos , Morfina/efeitos adversos , Agonistas de Receptores de Canabinoides/farmacologia , Analgésicos Opioides/efeitos adversos , Endocanabinoides , Canabinoides/efeitos adversos , Morfolinas/farmacologia , Encéfalo , Insuficiência Respiratória/induzido quimicamente , Receptores de Canabinoides
15.
Methods Mol Biol ; 2311: 167-175, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34033085

RESUMO

The use of sensory neurons and assessment of neurite outgrowth in vitro is an important part of understanding neuronal development and plasticity. Cultures of rat dorsal root ganglion (DRG) neurons provide quantitative results very quickly and, when grown on growth promoting or inhibitory substrates, can be utilized to study axonal growth, neurotrophic dependence, and structure and function of growth cones. Since we are interested in axon regeneration and targeting, we have sought to promote neurite outgrowth by refining the techniques of growing DRG neurons in culture. This chapter describes detailed methods for the dissection and purification of DRG neurons and quantitative assessment of neurite on promoting or inhibitory substrates.


Assuntos
Gânglios Espinais/efeitos dos fármacos , Crescimento Neuronal/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Animais , Técnicas de Cultura de Células , Células Cultivadas , Gânglios Espinais/citologia , Neurônios/fisiologia , Ratos Sprague-Dawley
16.
J Hum Lact ; 37(4): 813-820, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33656382

RESUMO

BACKGROUND: Dietary long-chain polyunsaturated fatty acids are known to benefit infant development. After birth, human milk provides arachidonic, eicosapentaenoic, and docosahexaenoic acids to the infant. Endocannabinoids are endogenous lipid mediators derived from the long-chain polyunsaturated fatty acids. Although the roles and the mechanisms of action are not fully understood, previous researchers have suggested that endocannabinoids might play a role in infant feeding behavior. RESEARCH AIMS: To assess (i) maternal dietary intake of long-chain polyunsaturated fatty acids and (ii) their relationship to concentrations of fatty acids and derived endocannabinoids in human milk. METHODS: For this exploratory-longitudinal study, participants (N = 24) provided dietary intake data and milk samples. Fatty acids and derived endocannabinoids: Arachidonylethanolamide, arachidonoylglycerol, docosahexaenoyl glycerol, eicosapentaenoyl ethanolamide, and eicosapenaenoyl glycerol were identified in their milk by liquid chromatography-mass spectrometry and correlations to dietary fatty acids were assessed. RESULTS: Participants were not consuming recommended amounts of docosahexaenoic acid. Significant correlations (p ≤ .05) were only found between dietary docosahexaenoic and eicosapentaenoic acids and the concentrations of these in human milk. Moreover, only dietary docosahexaenoic acid was correlated (p = .031) with its corresponding endocannabinoid, docosahexaenoyl glycerol. CONCLUSIONS: To the best of our knowledge, this may be one of the first studies evaluating relationships between dietary long-chain polyunsaturated fatty acids and multiple endocannabinoids in human milk. Our findings suggest that endocannabinoid concentrations could be modulated by dietary precursors. Future research studies can be designed based on these data to better elucidate the roles of endocannabinoids in human milk for infant health and development.


Assuntos
Endocanabinoides , Leite Humano , Aleitamento Materno , Criança , Ácidos Graxos , Feminino , Humanos , Lactente , Estudos Longitudinais
17.
Cannabis Cannabinoid Res ; 6(5): 401-412, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33998869

RESUMO

Introduction: An escalating number of fatalities resulting from accidental opioid overdoses typically attributed to respiratory depression continue to define the opioid epidemic. Opioid respiratory depression results from a decrease in reflexive inspiration within the preBötzinger complex in the brainstem. Objective: Cannabinoid receptor agonism is reported to enhance opioid analgesia, yet whether cannabinoids enhance or inhibit opioid-induced respiratory depression is unknown. Methods: Studies herein sought to define the roles of cannabinoid-1 receptor (CB1R) and cannabinoid-2 receptor (CB2R) on respiratory depression using selective agonists alone and in combination with morphine in male mice. Results: Using whole body plethysmography, the nonselective CB1R and CB2R agonist (Δ9-tetrahydrocannabinol) and the CB1R synthetic cannabinoid, AM356, induced respiratory depression, whereas the well-published selective CB2 agonist, JWH 133, and the novel CB2 agonist (AM2301) did not. Moreover, a selective CB2R agonist (AM2301) significantly attenuated morphine sulfate-induced respiratory depression. Conclusion: Notably, findings suggest that attenuation of opioid-induced respiratory depression relies on CB2R activation, supporting selective CB2R agonism as an opioid adjunct therapy.


Assuntos
Canabinoides , Insuficiência Respiratória , Analgésicos Opioides/efeitos adversos , Animais , Agonistas de Receptores de Canabinoides/farmacologia , Masculino , Camundongos , Morfina/efeitos adversos , Insuficiência Respiratória/induzido quimicamente
18.
Artigo em Inglês | MEDLINE | ID: mdl-32403455

RESUMO

This paper pioneers to investigate the endowment effect in the European Union mission Trading Scheme (EU ETS) as well as the impacts of trading experience and compliance pressure on the endowment effect. This study is based on the complete transaction records of the market. In the data set, the records of two consecutive reverse transactions from a same emitting company are selected. The lowest price that the buyer is willing to pay (WTP) and the maximum price the seller is willing to accept (WTA) are evaluated by excluding their risk cost that is used to avoid short-term fluctuations in the price. By distinguishing the difference between WTA and WTP, and long-term fluctuations in the prices during the two transactions, the trader's endowment effect can be quantitively assessed. The results show that the degree of endowment effect of traders follows the trading experience. In addition, since the EU ETS is a cap-and-trade market, the traders face different levels of compliance pressure; when the pressure of the emission companies increases, the degree of endowment effect will also decrease.


Assuntos
Comércio , Administração Financeira , União Europeia
19.
Front Neurol ; 11: 609, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32714271

RESUMO

The physiological mechanism underlying primary insomnia (PI) is poorly understood. Resting-state functional magnetic resonance imaging (fMRI) has emerged as a powerful tool to explore PI. However, previous studies ignore the dynamics of the brain activity. In the current study, we aimed to explore altered dynamic intrinsic brain activity in PI. Fifty-nine patients with PI and 47 matched healthy controls (HCs) were recruited and underwent resting-state fMRI. The variance of dynamic amplitude of low frequency fluctuation (dALFF) maps across time was calculated to measure the temporal variability of intrinsic brain activity and then compared between patients with PI and HCs. As a result, patients with PI presented increased variance of dALFF in the bilateral hippocampus extending to the parahippocampus, the right putamen and the right anterior insula cortex. In addition, the variance of dALFF in the right putamen was positively correlated with Self-rating Anxiety Scale (SAS) score in PI. Our results revealed increased instability of intrinsic activity in PI.

20.
Am J Otolaryngol ; 30(1): 8-16, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19027507

RESUMO

OBJECTIVE: The aim of the study is to investigate the survival of neural stem cells (NSCs) in normal rat cochlea and their potential effect on auditory function and cochlea structures via round window transplantation. METHODS: In comparison with the normal rats without any transplantation (group III), normal rat cochleae were transplanted with NSCs infected with adenovirus carrying green fluorescence protein (GFP) gene (group I) or the artificial perilymph (group II) via round windows. Auditory functions were monitored by thresholds of auditory brain stem responses (ABRs); the cochlea structures were examined by hematoxylin and eosin staining; survivals of implanted NSCs were determined by the expression of GFP; survivals of hair cells were accessed by whole mount preparation; and ultrastructures of hair cells were examined by scanning electron microscopy. RESULT: There were significant differences in the click-ABR thresholds in rats among all 3 groups neither at pretransplantation nor at posttransplantation; there were no significant differences in these values before and after transplantation in the same rats from each group. After transplantation, the cochlea structures were normal in both group I and group II. Grafted NSCs were visualized by the GFP expression in every turn of the cochlea in all animals of group I. There were no significant differences in the losses of outer hair cells (OHCs) among 3 groups. The inner hair cells and most OHCs were normal in every turns of cochleae of all groups. CONCLUSION: Neural stem cells survived in normal rat cochlea after transplantation via round window and showed no obvious effects on auditory functions and inner ear pathologic examination of the rat cochlea.


Assuntos
Células Ciliadas Auditivas/transplante , Janela da Cóclea/patologia , Janela da Cóclea/cirurgia , Transplante de Células-Tronco/métodos , Adenoviridae , Animais , Limiar Auditivo/fisiologia , Modelos Animais de Doenças , Potenciais Evocados Auditivos do Tronco Encefálico , Proteínas de Fluorescência Verde , Células Ciliadas Auditivas/ultraestrutura , Imuno-Histoquímica , Microscopia Eletrônica , Probabilidade , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Valores de Referência , Sensibilidade e Especificidade
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