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1.
Nature ; 583(7816): 459-468, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32353859

RESUMO

A newly described coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is the causative agent of coronavirus disease 2019 (COVID-19), has infected over 2.3 million people, led to the death of more than 160,000 individuals and caused worldwide social and economic disruption1,2. There are no antiviral drugs with proven clinical efficacy for the treatment of COVID-19, nor are there any vaccines that prevent infection with SARS-CoV-2, and efforts to develop drugs and vaccines are hampered by the limited knowledge of the molecular details of how SARS-CoV-2 infects cells. Here we cloned, tagged and expressed 26 of the 29 SARS-CoV-2 proteins in human cells and identified the human proteins that physically associated with each of the SARS-CoV-2 proteins using affinity-purification mass spectrometry, identifying 332 high-confidence protein-protein interactions between SARS-CoV-2 and human proteins. Among these, we identify 66 druggable human proteins or host factors targeted by 69 compounds (of which, 29 drugs are approved by the US Food and Drug Administration, 12 are in clinical trials and 28 are preclinical compounds). We screened a subset of these in multiple viral assays and found two sets of pharmacological agents that displayed antiviral activity: inhibitors of mRNA translation and predicted regulators of the sigma-1 and sigma-2 receptors. Further studies of these host-factor-targeting agents, including their combination with drugs that directly target viral enzymes, could lead to a therapeutic regimen to treat COVID-19.


Assuntos
Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/metabolismo , Reposicionamento de Medicamentos , Terapia de Alvo Molecular , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/metabolismo , Mapas de Interação de Proteínas , Proteínas Virais/metabolismo , Animais , Antivirais/classificação , Antivirais/farmacologia , Betacoronavirus/genética , Betacoronavirus/metabolismo , Betacoronavirus/patogenicidade , Chlorocebus aethiops , Clonagem Molecular , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Avaliação Pré-Clínica de Medicamentos , Células HEK293 , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Imunidade Inata , Espectrometria de Massas , Pandemias , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Ligação Proteica , Biossíntese de Proteínas/efeitos dos fármacos , Domínios Proteicos , Mapeamento de Interação de Proteínas , Receptores sigma/metabolismo , Proteínas Ligases SKP Culina F-Box/metabolismo , Células Vero , Proteínas Virais/genética
2.
Science ; 368(6486): 54-60, 2020 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-32193362

RESUMO

The endoplasmic reticulum (ER) engages mitochondria at specialized ER domains known as mitochondria-associated membranes (MAMs). Here, we used three-dimensional high-resolution imaging to investigate the formation of pleomorphic "megamitochondria" with altered MAMs in brown adipocytes lacking the Sel1L-Hrd1 protein complex of ER-associated protein degradation (ERAD). Mice with ERAD deficiency in brown adipocytes were cold sensitive and exhibited mitochondrial dysfunction. ERAD deficiency affected ER-mitochondria contacts and mitochondrial dynamics, at least in part, by regulating the turnover of the MAM protein, sigma receptor 1 (SigmaR1). Thus, our study provides molecular insights into ER-mitochondrial cross-talk and expands our understanding of the physiological importance of Sel1L-Hrd1 ERAD.


Assuntos
Adipócitos Marrons/fisiologia , Estresse do Retículo Endoplasmático/fisiologia , Degradação Associada com o Retículo Endoplasmático/fisiologia , Mitocôndrias/metabolismo , Dinâmica Mitocondrial , Termogênese/fisiologia , Adipócitos Marrons/metabolismo , Animais , Temperatura Baixa , Estresse do Retículo Endoplasmático/genética , Degradação Associada com o Retículo Endoplasmático/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Camundongos , Camundongos Mutantes , Mitocôndrias/ultraestrutura , Membranas Mitocondriais/metabolismo , Receptores sigma/metabolismo , Termogênese/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
3.
Carbohydr Polym ; 229: 115498, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31826492

RESUMO

Controlled release and tumor-selective distribution are highly desirable for anticancer nanomedicines. Here, we design and synthesize an anisamide-conjugated N-octyl-N,O-maleoyl-O-phosphoryl chitosan (a-OMPC) which can form amphiphilic micelles featuring pH-responsive release and high affinity to sigma-1 receptor-overexpressed tumors for paclitaxel (PTX) delivery. Thereinto, maleoyl and phosphoryl groups cooperatively contribute to pH-responsive drug release due to a conversion from hydrophile to hydrophobe in the acidic microenvironment of endo/lysosomes. We demonstrated that PTX-loaded a-OMPC micelles (PTX-aM) enhanced the cellular internalization via the affinity between anisamide and sigma-1 receptor, rapidly released drug in endo/lysosomes and elevated the cytotoxicity against PC-3 cells. The in vivo studies further verified that PTX-aM could largely accumulate at the tumor site even after 24 h of administration, resulting in obvious inhibition effect and prolonged survival period in PC-3 tumor xenograft-bearing mice. Moreover, OMPC showed no obvious hemolytic and acute toxicity. Collectively, this chitosan derivate holds a promising potential in application of prostate cancer-targeted drug delivery system.


Assuntos
Quitosana/química , Interações Hidrofóbicas e Hidrofílicas , Terapia de Alvo Molecular , Paclitaxel/química , Paclitaxel/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Receptores sigma/metabolismo , Animais , Quitosana/toxicidade , Preparações de Ação Retardada , Portadores de Fármacos/química , Portadores de Fármacos/toxicidade , Regulação Neoplásica da Expressão Gênica , Hemólise/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Masculino , Teste de Materiais , Camundongos , Micelas , Células PC-3 , Paclitaxel/uso terapêutico , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Adv Exp Med Biol ; 1131: 699-718, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31646531

RESUMO

Calcium exchanges and homeostasis are finely regulated between cellular organelles and in response to physiological signals. Besides ionophores, including voltage-gated Ca2+ channels, ionotropic neurotransmitter receptors, or Store-operated Ca2+ entry, activity of regulatory intracellular proteins finely tune Calcium homeostasis. One of the most intriguing, by its unique nature but also most promising by the therapeutic opportunities it bears, is the sigma-1 receptor (Sig-1R). The Sig-1R is a chaperone protein residing at mitochondria-associated endoplasmic reticulum (ER) membranes (MAMs), where it interacts with several partners involved in ER stress response, or in Ca2+ exchange between the ER and mitochondria. Small molecules have been identified that specifically and selectively activate Sig-1R (Sig-1R agonists or positive modulators) at the cellular level and that also allow effective pharmacological actions in several pre-clinical models of pathologies. The present review will summarize the recent data on the mechanism of action of Sig-1R in regulating Ca2+ exchanges and protein interactions at MAMs and the ER. As MAMs alterations and ER stress now appear as a common track in most neurodegenerative diseases, the intracellular action of Sig-1R will be discussed in the context of the recently reported efficacy of Sig-1R drugs in pathologies like Alzheimer's disease, Parkinson's disease, Huntington's disease, or amyotrophic lateral sclerosis.


Assuntos
Membrana Celular , Estresse do Retículo Endoplasmático , Doenças Neurodegenerativas , Receptores sigma , Membrana Celular/metabolismo , Membrana Celular/patologia , Humanos , Mitocôndrias/metabolismo , Doenças Neurodegenerativas/fisiopatologia , Receptores sigma/metabolismo
5.
Adv Exp Med Biol ; 1185: 463-467, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31884655

RESUMO

Retinitis pigmentosa (RP) is a blinding disease for which there is no known cure. In a recent study, we reported dramatic rescue of cones in the rd10 mouse model of RP when mice were treated systemically with (+)-pentazocine ((+)-PTZ), a high-affinity ligand for sigma 1 receptor (Sig1R). The molecular mechanisms by which Sig1R provides neuroprotection are unclear. In this report, we used a miRNA PCR array to compare 84 abundantly expressed, well-characterized miRNAs in rd10/Sig1R-/- vs. rd10 and rd10 + PTZ vs. rd10 mice. We found that 13 miRNAs were significantly increased in rd10/Sig1R-/- retinas but were significantly decreased in rd10 + PTZ retinas. The miRNAs were miR-9-5p, miR-27a-3p, miR-126a-5p, miR-146a-5p, miR-10a-5p, miR-34c-5p, miR-503-5p, miR-30c-5p, miR-199-5p, miR-541-5p, miR-214-3p, miR-218-5p, and miR-335-5p. Of these, miR-214-3p is closely related to oxidative stress modulation, which is relevant to degenerative retinopathy. MiR-214-3p expression is ~fivefold higher in rd10/Sig1R-/- vs. rd10. In contrast, miR-214-3p is decreased ~twofold in rd10 + PTZ vs. rd10. Interestingly, miR-214-3p is predicted to bind to Sig1R and Nrf2, a key transcription factor for modulation of oxidative stress. To our knowledge, this is the first evidence that Sig1R may interact with miRNAs in retina. This observation is the underpinning of our hypothesis that a novel mechanism by which Sig1R mediates cone rescue is via interaction with miR-214-3p.


Assuntos
MicroRNAs/metabolismo , Neuroproteção , Pentazocina/farmacologia , Receptores sigma/metabolismo , Células Fotorreceptoras Retinianas Cones/efeitos dos fármacos , Retinite Pigmentosa , Animais , Camundongos , Retina
6.
Dokl Biochem Biophys ; 488(1): 307-310, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31768847

RESUMO

Using Fura-2AM microfluorimetry, we have shown for the first time that sigma-1 receptor agonist-tricyclic antidepressant amitriptyline-significantly inhibits store-dependent Ca2+ entry, induced by endoplasmic Ca2+-ATPase inhibitors thapsigargin and cyclopiazonic acid, in rat peritoneal macrophages. The results suggest a possible involvement of sigma-1 receptors in the regulation of store-dependent Ca2+ entry in macrophages.


Assuntos
Amitriptilina/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Cálcio/metabolismo , Macrófagos Peritoneais/metabolismo , Receptores sigma/agonistas , Animais , Indóis/farmacologia , Transporte de Íons/efeitos dos fármacos , Ratos , Ratos Wistar , Receptores sigma/metabolismo , Tapsigargina/farmacologia
7.
Bull Exp Biol Med ; 168(1): 33-37, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31741244

RESUMO

A translational rat model of chronic heart failure was employed to examine the cardioprotective effect of fabomotizole hydrochloride. Fabomotizole therapy for 28 days (15 mg/kg/day intraperitoneally) restored inotropic function of the left ventricle and increased ejection fraction from 54±3 to 65±3% (p=0.001). The inotropic function returned to normal against the background of significantly reduced myocardial expression of angiotensin (p=0.01) and glucocorticoid (p=0.03) receptors and significant increased expression of sigma-1 receptors (p=0.04). Inhibition of abnormal expression of angiotensin and glucocorticoid receptors responsible for activation of the pathological cascades underlying the postinfarction remodeling of the left ventricle as well as activation of the expression of cytoprotective sigma-1 receptors are viewed as the key features of the cardioprotective action of fabomotizole hydrochloride.


Assuntos
Benzimidazóis/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Angiotensinas/metabolismo , Animais , Ecocardiografia , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/metabolismo , Ratos , Receptores de Glucocorticoides/metabolismo , Receptores sigma/metabolismo
8.
Elife ; 82019 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-31596232

RESUMO

Cocaine is an addictive drug that acts in brain reward areas. Recent evidence suggests that cocaine stimulates synthesis of the endocannabinoid 2-arachidonoylglycerol (2-AG) in midbrain, increasing dopamine neuron activity via disinhibition. Although a mechanism for cocaine-stimulated 2-AG synthesis is known, our understanding of 2-AG release is limited. In NG108 cells and mouse midbrain tissue, we find that 2-AG is localized in non-synaptic extracellular vesicles (EVs) that are secreted in the presence of cocaine via interaction with the chaperone protein sigma-1 receptor (Sig-1R). The release of EVs occurs when cocaine causes dissociation of the Sig-1R from ADP-ribosylation factor (ARF6), a G-protein regulating EV trafficking, leading to activation of myosin light chain kinase (MLCK). Blockade of Sig-1R function, or inhibition of ARF6 or MLCK also prevented cocaine-induced EV release and cocaine-stimulated 2-AG-modulation of inhibitory synapses in DA neurons. Our results implicate the Sig-1R-ARF6 complex in control of EV release and demonstrate that cocaine-mediated 2-AG release can occur via EVs.


Assuntos
Cocaína/farmacologia , Endocanabinoides/metabolismo , Vesículas Extracelulares/metabolismo , Receptores sigma/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Ribosilação do ADP/metabolismo , Animais , Mesencéfalo/efeitos dos fármacos , Mesencéfalo/metabolismo , Camundongos , Quinase de Cadeia Leve de Miosina/metabolismo
9.
Invest Ophthalmol Vis Sci ; 60(13): 4397-4407, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31639826

RESUMO

Purpose: Retinitis pigmentosa (RP), a retinal photoreceptor degeneration, typically affects rod function and subsequently cones. Activation of sigma 1 receptor (Sig1R) has been shown to preserve cone function through 6 weeks in the rd10 mouse model of RP, when mice were treated systemically with the Sig1R ligand (+)-pentazocine (PTZ). This study determined the extent to which cone function is preserved in rd10 mice when Sig1R is activated. Methods: Rd10 mice were administered (+)-PTZ (alternate days beginning at postnatal day [P]14) over a period of 180 days. Mouse visual function and structure were measured in vivo using optokinetic tracking response, scotopic and photopic electroretinography plus photopic assessment using "natural" noise stimuli, and optical coherence tomography (OCT). Immunofluorescent methods were used to detect cones in retinal cryosections. Results: Visual acuity was maintained in rd10(+)-PTZ-treated mice through P56, whereas rd10 nontreated mice showed marked decline by P28. Cone responses were detected in (+)-PTZ-treated mice through P60, which were more robust when tested with natural noise stimuli; cone responses were minimal in nontreated rd10 mice. OCT revealed significantly thicker retinas in (+)-PTZ-treated rd10 mice through P60 compared to nontreated mice. Cones were detected by immunofluorescence in (+)-PTZ-treated rd10 retinas through P120. Conclusions: The extent to which cone rescue could be sustained in (+)-PTZ-treated rd10 mice was evaluated comprehensively, showing that activation of Sig1R is associated with prolonged visual acuity, extended detection of cone function, and detection of cones in retinal histologic sections. The data reflect promising long-term neuroprotection when Sig1R is activated.


Assuntos
Analgésicos Opioides/uso terapêutico , Modelos Animais de Doenças , Pentazocina/uso terapêutico , Receptores sigma/metabolismo , Células Fotorreceptoras Retinianas Cones/fisiologia , Retinite Pigmentosa/tratamento farmacológico , Acuidade Visual/efeitos dos fármacos , Animais , Sobrevivência Celular/fisiologia , Visão de Cores/fisiologia , Eletrorretinografia , Pressão Intraocular , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Visão Noturna/fisiologia , Nistagmo Optocinético/fisiologia , Retina/metabolismo , Retina/fisiopatologia , Retinite Pigmentosa/metabolismo , Retinite Pigmentosa/fisiopatologia , Tomografia de Coerência Óptica , Acuidade Visual/fisiologia
10.
Neurochem Res ; 44(11): 2536-2545, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31529334

RESUMO

Dehydrocorybulbine (DHCB), an alkaloid from Corydalis yanhusuo. W.T, has been identified as a dopamine receptor antagonist. We extended our assessment of its pharmacological profile and found that DHCB exhibits high to moderate binding affinities to sigma 1 and 2 receptors, serotonin 5-HT7 receptor, and histamine H2 receptors. This led us to evaluate DHCB properties in pharmacological (apomorphine and MK-801) animal models of schizophrenia in mice. The pharmacological profile of DHCB was screened through radioligand receptor binding assays. Single dose of DHCB reversed the locomotor hyperactivity, stereotypy, and prepulse inhibition deficits induced by the dopaminergic agonist apomorphine. DHCB also reversed the depressive-like behavior and memory deficit induced by the glutamatergic antagonist MK-801 in the forced swim and the novel object recognition assays, respectively. These results indicate that DHCB effectively improves schizophrenia-like behavioral deficits that are induced by the disruption of dopaminergic and glutamatergic systems. The effectiveness of DHCB in reversing responses that mimic negative and cognitive deficits of schizophrenia might suggest that its anti-schizophrenia effects are mediated through modulating the activities of several receptor particularly sigma 1, sigma 2, 5-HT7 and dopamine receptors. Our study casts DHCB as a promising lead for therapeutic treatment of schizophrenia.


Assuntos
Antipsicóticos/uso terapêutico , Isoquinolinas/uso terapêutico , Receptores de Serotonina/metabolismo , Receptores sigma/metabolismo , Esquizofrenia/tratamento farmacológico , Animais , Apomorfina , Maleato de Dizocilpina , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Receptores Histamínicos H2/metabolismo , Esquizofrenia/induzido quimicamente
11.
Life Sci ; 235: 116837, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31493481

RESUMO

AIMS: This study aimed to evaluate the effects of the sigma-1 receptor (S1R) on atrial fibrillation (AF) susceptibility in rats. MAIN METHODS: Rats were randomly assigned into three groups for intraperitoneal treatment with saline (CTL group), BD1047 (an antagonist of the S1R, BD group) or BD1047 plus fluvoxamine (an agonist of the S1R, BD + F group) for 4 weeks. The heart rate variability (HRV) and atrial electrophysiological parameters were measured via the PowerLab system and analyzed by LabChart 8.0 software. Atrial histology was determined with Masson staining. The protein levels of connexin (Cx) 40, Cav1.2, S1R, eNOS, p-eNOS, and p-AKT were detected by western blot assays. KEY FINDINGS: Our results showed that BD1047 significantly shortened the atrial effective refractory period (ERP) and action potential duration (APD), increased AF inducibility and duration, augmented sympathetic activity, depressed parasympathetic activity, and reduced heart rate variability (HRV) compared with the CTL group. Masson staining also showed a significant increase in atrial fibrosis in the BD group. Furthermore, the expressions of S1R, Cx40, Cav1.2, p-eNOS, and p-AKT were dramatically reduced in the BD group compared with the CTL group (all P < 0.01). However, fluvoxamine administration mitigated most of the abovementioned alterations. SIGNIFICANCE: Our findings indicated that S1R inhibition contributed to atrial electrical remodeling, cardiac autonomic remodeling and atrial fibrosis, which could be attenuated by fluvoxamine, thus providing new insights into the relationship between the S1R and AF.


Assuntos
Fibrilação Atrial/fisiopatologia , Remodelamento Atrial/fisiologia , Receptores sigma/antagonistas & inibidores , Receptores sigma/fisiologia , Potenciais de Ação , Animais , Fibrilação Atrial/patologia , Canais de Cálcio Tipo L , Conexinas/metabolismo , Etilenodiaminas/farmacologia , Fluvoxamina/farmacologia , Átrios do Coração/efeitos dos fármacos , Átrios do Coração/metabolismo , Átrios do Coração/patologia , Frequência Cardíaca/efeitos dos fármacos , Masculino , Óxido Nítrico Sintase Tipo III/metabolismo , Proteína Oncogênica v-akt/metabolismo , Ratos , Receptores sigma/agonistas , Receptores sigma/metabolismo
12.
Chem Pharm Bull (Tokyo) ; 67(9): 897-903, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31474726

RESUMO

The word "theranostics," a portmanteau word made by combining "therapeutics" and "diagnostics," refers to a personalized medicine concept. Recently, the word, "radiotheranostics," has also been used in nuclear medicine as a term that refer to the use of radioisotopes for combined imaging and therapy. For radiotheranostics, a diagnostic probe and a corresponding therapeutic probe can be prepared by introducing diagnostic and therapeutic radioisotopes into the same precursor. These diagnostic and therapeutic probes can be designed to show equivalent pharmacokinetics, which is important for radiotheranostics. As imaging can predict the absorbed radiation dose and thus the therapeutic and side effects, radiotheranostics can help achieve the goal of personalized medicine. In this review, I discuss the use of radiolabeled probes targeting bone metastases, sigma-1 receptor, and αVß3 integrin for radiotheranostics.


Assuntos
Neoplasias Ósseas/diagnóstico , Compostos Radiofarmacêuticos/química , Animais , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/radioterapia , Meios de Contraste/química , Meios de Contraste/metabolismo , Humanos , Oligopeptídeos/química , Oligopeptídeos/metabolismo , Oligopeptídeos/uso terapêutico , Compostos Radiofarmacêuticos/farmacocinética , Compostos Radiofarmacêuticos/uso terapêutico , Receptores sigma/química , Receptores sigma/metabolismo , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único , Distribuição Tecidual
13.
J Pharmacol Exp Ther ; 370(3): 480-489, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31300611

RESUMO

Opioids promote tumor angiogenesis in mammary malignancies, but the underlying signaling mechanism is largely unknown. The current study investigated the hypothesis that stimulation of δ-opioid receptors (DOR) in breast cancer (BCa) cells activates the hypoxia-inducible factor 1α (HIF-1α), which triggers synthesis and release of diverse angiogenic factors. Immunoblotting revealed that incubation of human MCF-7 and T47D breast cancer cells with the DOR agonist d-Ala2,d-Leu5-enkephalin (DADLE) resulted in a transient accumulation and thus activation of HIF-1α DADLE-induced HIF-1α activation preceded PI3K/Akt stimulation and was blocked by the DOR antagonist naltrindole and naloxone, pertussis toxin, different phosphoinositide 3-kinase (PI3K) inhibitors, and the Akt inhibitor Akti-1/2. Whereas DADLE exposure had no effect on the expression and secretion of vascular endothelial growth factor (VEGF) in BCa cells, an increased abundance of cyclooxygenase-2 (COX-2) and release of prostaglandin E2 (PGE2) was detected. DADLE-induced COX-2 expression was also observed in three-dimensional cultured MCF-7 cells and impaired by PI3K/Akt inhibitors and the HIF-1α inhibitor echinomycin. Supernatant from DADLE-treated MCF-7 cells triggered sprouting of endothelial (END) cells, which was blocked when MCF-7 cells were pretreated with echinomycin or the COX-2 inhibitor celecoxib. Also no sprouting was observed when END cells were exposed to the PGE2 receptor antagonist PF-04418948. The findings together indicate that DOR stimulation in BCa cells leads to PI3K/Akt-dependent HIF-1α activation and COX-2 expression, which trigger END cell sprouting by paracrine activation of PGE2 receptors. These findings provide a potential mechanism of opioid-driven tumor angiogenesis and thus therapeutic targets to combat the tumor-angiogenic opioid effect. SIGNIFICANCE STATEMENT: Opioids are indispensable analgesics for treating cancer-related pain. However, opioids were found to promote tumor growth and metastasis, which questions the use of these potent pain-relieving drugs in cancer patients. Enhanced tumor vascularization after opioid treatment implies that tumor progression results from angiogenic opioid effects. Thus, understanding the signaling mechanism of opioid-driven tumor angiogenesis helps to identify therapeutic targets to combat these undesired tumor effects. The present study reveals that stimulation of δ-opioid receptors in breast cancer cells leads to an activation of HIF-1α and expression of COX-2 via PI3K/Akt stimulation, which results in a paracrine activation of vascular endothelial cells by prostaglandin E2 receptors.


Assuntos
Neoplasias da Mama/patologia , Ciclo-Oxigenase 2/metabolismo , Células Endoteliais/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Comunicação Parácrina/efeitos dos fármacos , Receptores sigma/agonistas , Dinoprostona/metabolismo , Leucina Encefalina-2-Alanina/farmacologia , Humanos , Células MCF-7 , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Receptores sigma/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo
14.
Physiol Rep ; 7(12): e14147, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31222975

RESUMO

Expression of Kv1.2 within Kv1.x potassium channel complexes is critical in maintaining appropriate neuronal excitability and determining the threshold for action potential firing. This is attributed to the interaction of Kv1.2 with a hitherto unidentified protein that confers bimodal channel activation gating, allowing neurons to adapt to repetitive trains of stimulation and protecting against hyperexcitability. One potential protein candidate is the sigma-1 receptor (Sig-1R), which regulates other members of the Kv1.x channel family; however, the biophysical nature of the interaction between Sig-1R and Kv1.2 has not been elucidated. We hypothesized that Sig-1R may regulate Kv1.2 and may further act as the unidentified modulator of Kv1.2 activation. In transiently transfected HEK293 cells, we found that ligand activation of the Sig-1R modulates Kv1.2 current amplitude. More importantly, Sig-1R interacts with Kv1.2 in baseline conditions to influence bimodal activation gating. These effects are abolished in the presence of the auxiliary subunit Kvß2 and when the Sig-1R mutation underlying ALS16 (Sig-1R-E102Q), is expressed. These data suggest that Kvß2 occludes the interaction of Sig-1R with Kv1.2, and that E102 may be a residue critical for Sig-1R modulation of Kv1.2. The results of this investigation describe an important new role for Sig-1R in the regulation of neuronal excitability and introduce a novel mechanism of pathophysiology in Sig-1R dysfunction.


Assuntos
Canal de Potássio Kv1.2/fisiologia , Receptores sigma/fisiologia , Células Cultivadas , Fenômenos Eletrofisiológicos/efeitos dos fármacos , Fenômenos Eletrofisiológicos/fisiologia , Células HEK293 , Humanos , Ativação do Canal Iônico/fisiologia , Canal de Potássio Kv1.2/efeitos dos fármacos , Canal de Potássio Kv1.2/metabolismo , Técnicas de Patch-Clamp/métodos , Fenazocina/análogos & derivados , Fenazocina/antagonistas & inibidores , Fenazocina/farmacologia , Receptores sigma/agonistas , Receptores sigma/metabolismo , Superfamília Shaker de Canais de Potássio/fisiologia
15.
Psychopharmacology (Berl) ; 236(11): 3147-3158, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31139878

RESUMO

RATIONALE: Previous research indicates that the selective sigma-1 receptor ligand PD144418 and the selective sigma-2 ligands YUN-252 can inhibit cocaine-induced hyperactivity. The effects of these ligands on other stimulants, such as methamphetamine, have not been reported. OBJECTIVES: The present study examined the effects of PD144418 and YUN-252 pretreatment on methamphetamine-induced hyperactivity after acute treatment. METHODS: Mice (n = 8-14/group) were injected with PD144418 (3.16, 10, or 31.6 µmol/kg), YUN-252 (0.316, 3.16, 31.6 µmol/kg), or saline. After 15 min, mice injected with 2.69 µmol/kg methamphetamine or saline vehicle, where distance traveled during a 60-min period was recorded. Additionally, the effect of PD144418 on the initiation and expression of methamphetamine sensitization was determined by treating mice (n = 8-14/group) with PD144418, methamphetamine or saline repeatedly over a 5-day period, and testing said mice with a challenge dose after a 7-day withdrawal period. RESULTS: Results indicate that both PD144418 and YUN-252, in a dose-dependent manner, attenuated hyperactivity induced by an acute methamphetamine injection. Specifically, 10 µmol/kg or 31.6 µmol/kg of PD144418 and 31 µmol/kg of YUN-252 suppressed methamphetamine-induced hyperactivity. In regard to methamphetamine sensitization, while 10 µmol/kg PD144418 prevented the initiation of methamphetamine sensitization, it did not have an effect on the expression. CONCLUSIONS: Overall, the current results suggest an intriguing potential for this novel sigma receptor ligand as a treatment for the addictive properties of methamphetamine. Future analysis of this novel sigma receptor ligand in assays directly measuring reinforcement properties will be critical.


Assuntos
Estimulantes do Sistema Nervoso Central/farmacologia , Isoxazóis/metabolismo , Locomoção/efeitos dos fármacos , Metanfetamina/farmacologia , Piridinas/metabolismo , Receptores sigma/metabolismo , Animais , Estimulantes do Sistema Nervoso Central/antagonistas & inibidores , Isoxazóis/farmacologia , Ligantes , Locomoção/fisiologia , Masculino , Camundongos , Piridinas/farmacologia , Receptores sigma/antagonistas & inibidores , Reforço Psicológico
16.
Neurobiol Dis ; 129: 118-129, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31108174

RESUMO

Huntington's disease (HD) is a neurodegenerative disease caused by a CAG repeat expansion in the Huntingtin gene (HTT), translated into a Huntingtin protein with a polyglutamine expansion. There is preferential loss of medium spiny neurons within the striatum and cortical pyramidal neurons. Pridopidine is a small molecule showing therapeutic potential in HD preclinical and clinical studies. Pridopidine has nanomolar affinity to the sigma-1 receptor (sigma-1R), which is located predominantly at the endoplasmic reticulum (ER) and mitochondrial associated ER membrane, and activates neuroprotective pathways. Here we evaluate the neuroprotective effects of pridopidine against mutant Huntingtin toxicity in mouse and human derived in vitro cell models. We also investigate the involvement of the sigma-1 receptor in the mechanism of pridopidine. Pridopidine protects mutant Huntingtin transfected mouse primary striatal and cortical neurons, with an EC50 in the mid nanomolar range, as well as HD patient-derived induced pluripotent stem cells (iPSCs). This protection by pridopidine is blocked by NE-100, a purported sigma-1 receptor antagonist, and not blocked by ANA-12, a reported TrkB receptor antagonist. 3PPP, a documented sigma-1 receptor agonist, shows similar neuroprotective effects. Genetic knock out of the sigma-1 receptor dramatically decreases protection from pridopidine and 3PPP, but not protection via brain derived neurotrophic factor (BDNF). The neuroprotection afforded by pridopidine in our HD cell models is robust and sigma-1 receptor dependent. These studies support the further development of pridopidine, and other sigma-1 receptor agonists as neuroprotective agents for HD and perhaps for other disorders.


Assuntos
Proteína Huntingtina/metabolismo , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Piperidinas/farmacologia , Receptores sigma/metabolismo , Animais , Células Cultivadas , Humanos , Proteína Huntingtina/genética , Doença de Huntington/metabolismo , Camundongos , Camundongos Knockout , Neurônios/metabolismo , Neurônios/patologia
17.
Pharmacol Res ; 144: 315-330, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31048034

RESUMO

The sigma-1 (σ1) receptor is an endoplasmic reticulum (ER) chaperone protein, enriched in mitochondria-associated membranes. Its activation triggers physiological responses to ER stress and modulate Ca2+ mobilization in mitochondria. Small σ1 agonist molecules activate the protein and act behaviorally as antidepressant, anti-amnesic and neuroprotective agents. Recently, several chemically unrelated molecules were shown to be σ1 receptor positive modulators (PMs), with some of them a clear demonstration of their allostericity. We here examined whether a σ1 PM also shows neuroprotective potentials in pharmacological and genetic models of Alzheimer's disease (AD). For this aim, we describe (±)-2-(3-chlorophenyl)-3,3,5,5-tetramethyl-2-oxo-[1,4,2]-oxazaphosphinane (OZP002) as a novel σ1 PM. OZP002 does not bind σ1 sites but induces σ1 effects in vivo and boosts σ1 agonist activity. OZP002 was antidepressant in the forced swim test and its effect was blocked by the σ1 antagonist NE-100 or in σ1 receptor knockout mice. It potentiated the antidepressant effect of the σ1 agonist igmesine. In mice tested for Y-maze alternation or passive avoidance, OZP002 prevented scopolamine-induced learning deficits, in a NE-100 sensitive manner. Pre-administered IP before an ICV injection of amyloid Aß25-35 peptide, a pharmacological model of Alzheimer's disease, OZP002 prevented the learning deficits induced by the peptide after one week in the Y-maze, passive avoidance and novel object tests. Biochemical analyses of the mouse hippocampi showed that OZP002 significantly decreased Aß25-35-induced increases in reactive oxygen species, lipid peroxidation, and increases in Bax, TNFα and IL-6 levels. Immunohistochemically, OZP002 prevented Aß25-35-induced reactive astrogliosis and microgliosis in the hippocampus. It also alleviated Aß25-35-induced decreases in synaptophysin level and choline acetyltransferase activity. Moreover, chronically administered in APPswe mice during 2 months, OZP002 prevented learning deficits (in all tests plus place learning in the water-maze) and increased biochemical markers. This study shows that σ1 PM with high neuropotective potential can be identified, combining pharmacological efficacy, selectivity and therapeutic safety, and identifies a novel promising compound, OZP002.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Neuroproteção/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Receptores sigma/agonistas , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Receptores sigma/genética , Receptores sigma/metabolismo
18.
ChemMedChem ; 14(13): 1248-1256, 2019 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-31071238

RESUMO

The sigma-2 receptor has been shown to play important roles in a number of important diseases, including central nervous system (CNS) disorders and cancer. However, mechanisms by which sigma-2 contributes to these diseases remain unclear. The development of new sigma-2 ligands that can be used to probe the function of this protein and potentially as drug discovery leads is therefore of great importance. Herein we report the development of a series of tetrahydroindazole compounds that are highly potent and selective for sigma-2. Structure-activity relationship data were used to generate a pharmacophore model that summarizes the common features present in the potent ligands. Assays for solubility and microsomal stability showed that several members of this compound series possess promising characteristics for further development of useful chemical probes or drug discovery leads.


Assuntos
Indazóis/química , Receptores sigma/metabolismo , Desenho de Fármacos , Humanos , Indazóis/metabolismo , Ligantes , Microssomos/metabolismo , Ligação Proteica , Receptores sigma/química , Solubilidade , Relação Estrutura-Atividade
19.
Mol Neurobiol ; 56(10): 7045-7055, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30972626

RESUMO

The current study was performed to establish the actions of nanomolar concentrations of cocaine, not blocking the dopamine transporter, on dopamine D2 receptor (D2R)-sigma 1 receptor (δ1R) heteroreceptor complexes and the D2R protomer recognition, signaling and internalization in cellular models. We report the existence of D2R-δ1R heteroreceptor complexes in subcortical limbic areas as well as the dorsal striatum, with different distribution patterns using the in situ proximity ligation assay. Also, through BRET, these heteromers were demonstrated in HEK293 cells. Furthermore, saturation binding assay demonstrated that in membrane preparations of HEK293 cells coexpressing D2R and δ1R, cocaine (1 nM) significantly increased the D2R Bmax values over cells singly expressing D2R. CREB reporter luc-gene assay indicated that coexpressed δ1R significantly reduced the potency of the D2R-like agonist quinpirole to inhibit via D2R activation the forskolin induced increase of the CREB signal. In contrast, the addition of 100 nM cocaine was found to markedly increase the quinpirole potency to inhibit the forskolin-induced increase of the CREB signal in the D2R-δ1R cells. These events were associated with a marked reduction of cocaine-induced internalization of D2R protomers in D2R-δ1R heteromer-containing cells vs D2R singly expressing cells as studied by means of confocal analysis of D2R-δ1R trafficking and internalization. Overall, the formation of D2R-δ1R heteromers enhanced the ability of cocaine to increase the D2R protomer function associated with a marked reduction of its internalization. The existence of D2R-δ1R heteromers opens up a new understanding of the acute actions of cocaine.


Assuntos
Cocaína/farmacologia , Endocitose , Receptores de Dopamina D2/metabolismo , Receptores sigma/metabolismo , Transdução de Sinais , Animais , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Endocitose/efeitos dos fármacos , Genes Reporter , Células HEK293 , Humanos , Luciferases/metabolismo , Masculino , Prosencéfalo/efeitos dos fármacos , Prosencéfalo/metabolismo , Racloprida/farmacologia , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
20.
J Labelled Comp Radiopharm ; 62(8): 425-437, 2019 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-30991462

RESUMO

We report the design, synthesis, and evaluation of a new series of benzylpiperazine derivatives as selective σ1 receptor ligands. All seven ligands possessed low nanomolar affinity for σ1 receptors (Ki (σ1 ) = 0.31-4.19 nM) and high subtype selectivity (Ki (σ2 )/Ki (σ1 ) = 50-2448). The fluoroethoxy analogues also exhibited high selectivity toward the vesicular acetylcholine transporter (Ki (VAChT)/Ki (σ1 ) = 99-18252). The corresponding radiotracers [18 F]13, [18 F]14, and [18 F]16 with high selectivity (Ki (σ2 )/Ki (σ1 ) > 100, Ki (VAChT)/Ki (σ1 ) > 1000) were prepared in 42% to 55% radiochemical yields (corrected for decay), greater than 99% radiochemical purity (RCP), and molar activity of about 120 GBq/µmol at the end of synthesis (EOS). All three radiotracers showed high initial brain uptake in mouse (8.37-11.48% ID/g at 2 min), which was not affected by pretreatment with cyclosporine A, suggesting that they are not substrates for permeability-glycoprotein (P-gp). Pretreatment with SA4503 or haloperidol resulted in significantly reduced brain uptake (35%-62% decrease at 30 min). In particular, [18 F]16 displayed high brain-to-blood ratios and high in vivo metabolic stability. Although it may not be an optimal neuroimaging agent because of its slow kinetics in the mouse brain, [18 F]16 can serve as a lead compound for further structural modifications to explore new potential radiotracers for σ1 receptors.


Assuntos
Radioisótopos de Flúor/química , Piperazinas/química , Piperazinas/metabolismo , Tomografia por Emissão de Pósitrons , Receptores sigma/metabolismo , Animais , Transporte Biológico , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Estabilidade de Medicamentos , Marcação por Isótopo , Ligantes , Masculino , Camundongos , Camundongos Endogâmicos ICR , Piperazinas/farmacocinética , Radioquímica , Especificidade por Substrato , Distribuição Tecidual
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