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1.
J Chin Med Assoc ; 87(5): 538-549, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38587377

RESUMO

BACKGROUND: The neurotoxicity of 3,4-methylenedioxy-methamphetamine (MDMA) to the serotonergic system is well-documented. Dextromethorphan (DM), an antitussive drug, decreased morphine- or methamphetamine (MA)-induced reward in rats and may prevent MDMA-induced serotonergic deficiency in primates, as indicated by increased serotonin transporter (SERT) availability. We aimed to investigate the effects of DM on reward, behavioral sensitization, and neurotoxicity associated with loss of SERT induced by chronic MDMA administration in rats. METHODS: Conditioned place preference (CPP) and locomotor activity tests were used to evaluate drug-induced reward and behavioral sensitization; 4-[ 18 F]-ADAM/animal-PET and immunohistochemistry were used to explore the effects of DM on MDMA-induced loss of SERT. RESULTS: MDMA significantly reduced SERT binding in the rat brain; however, co-administration of DM significantly restored SERT, enhancing the recovery rate at day 14 by an average of ~23% compared to the MDMA group. In confirmation of the PET findings, immunochemistry revealed MDMA reduced SERT immunoactivity in all brain regions, whereas DM markedly increased the serotonergic fiber density after MDMA induction. CONCLUSION: Behavioral tests and in vivo longitudinal PET imaging demonstrated the CPP indexes and locomotor activities of the reward system correlate negatively with PET 4-[ 18 F]ADAM SERT activity in the reward system. Our findings suggest MDMA induces functional abnormalities in a network of brain regions important to decision-making processes and the motivation circuit. DM may exert neuroprotective effects to reverse MDMA-induced neurotoxicity.


Assuntos
Dextrometorfano , N-Metil-3,4-Metilenodioxianfetamina , Recompensa , Proteínas da Membrana Plasmática de Transporte de Serotonina , Animais , Masculino , Ratos , Dextrometorfano/farmacologia , N-Metil-3,4-Metilenodioxianfetamina/farmacologia , Tomografia por Emissão de Pósitrons , Ratos Sprague-Dawley , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo
2.
Front Aging Neurosci ; 14: 948848, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36466604

RESUMO

Extensive studies showed increased subjective pain sensitivity in Parkinson's disease (PD), which appeared to be partially reversed by dopaminergic (DA) treatment. Although cell replacement represents an attractive therapeutic strategy, its potential for PD-related hyperalgesia remains unclear. We investigated re-establishment of DA function via allografting exogenic DA cells on pain hypersensitivity in a rat model of PD. We evaluated the anti-nociceptive effects of fetal ventral mesencephalic (rVM) tissue allografts in PD rats after unilateral 6-OHDA-induced toxicity in the medial forebrain bundle. The drug -induced rotation test was used to validate the severity of the nigrostriatal lesion; von Frey and thermal pain tests were employed to evaluate nociceptive function. Nociception-induced cerebral blood volume (CBV) response was measured using a 4.7-T MR system. Finally, the immunohistochemical (IHC) studies were performed and the results were compared with the imaging findings from functional magnetic resonance imaging (fMRI). The grafts significantly improved drug-induced rotation behavior and increased mechanical and thermal nociceptive thresholds in PD rats. The elevation of CBV signals significantly recovered on the grafted striatum, whereas this effect was inhibited by the D2R antagonist eticlopride in each striatum. Quantitative IHC analysis revealed the transplantation markedly increased the numbers of tyrosine hydroxylase immunoreactive cells. Therefore, we concluded transplantation of rVM tissue results in anti-nociceptive effects and improves motor function. Moreover, in vivo CBV response confirmed the key role of D2R-mediated pain modulation. Therefore, we demonstrate fMRI as a reliable imaging index in evaluating the anti-nociceptive therapeutic effects of fetal rVM transplantation in the rat model of PD.

3.
PLoS One ; 16(8): e0255405, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34358247

RESUMO

The global incidence of diabetes mellitus (DM) is increasing. Types 1 and 2 DM are associated with declining ß-cell function. Verapamil (50% S-verapamil and 50% R-verapamil) can treat DM by downregulating thioredoxin-interacting protein (TXNIP), which induces islet ß-cell apoptosis. However, it may also induce cardiovascular side effects as S-verapamil is negatively inotropic. In contrast, R-verapamil only weakly induces adverse cardiac effects. In this study, we aimed to determine the antidiabetic efficacy and cardiovascular safety of R-verapamil. We examined R- and S-verapamil binding through in vitro studies. Streptozotocin-induced type 1 and db/db type 2 DM mouse models were used to assess the antidiabetic efficacy of verapamil. IL-6, blood glucose (BG), Txnip expression, and ß-cells were evaluated in streptozotocin-induced diabetic mice, while body weight, BG, and serum insulin were measured in the db/db mice. In the type 1 DM study, 100 mg/kg/day R-verapamil and racemic verapamil lowered BG, downregulated Txnip expression, and reduced ß-cell apoptosis. In the type 2 DM study, the optimal R-verapamil dosage was 60 mg/kg/day and it lowered BG and raised serum insulin. However, efficacy did not increase with R-verapamil dosage. R-verapamil combined with metformin/acarbose improved BG and serum insulin more effectively than metformin/acarbose alone or verapamil combined with acarbose. R-verapamil had weaker cardiovascular side effects than S-verapamil. R-verapamil was 9.0× and 3.4× less effective than S-verapamil at inhibiting atrial inotropy and ileal contractility, respectively. It was also 8.7× weaker than S-verapamil as an agonist of somatostatin receptor type 2 (SSTR2), inhibiting ileal neurogenic contraction. Hence, R-verapamil may be an optimal DM treatment as it is safe, improves glycemic control, and preserves ß-cell function both as monotherapy and in combination with metformin or acarbose. R-Verapamil has potential for delaying or arresting DM progression and improving patients' quality of life.


Assuntos
Diabetes Mellitus Experimental , Hipoglicemiantes , Animais , Diabetes Mellitus Tipo 2 , Masculino , Camundongos , Qualidade de Vida
4.
Xenotransplantation ; 27(2): e12569, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31777103

RESUMO

BACKGROUND: Parkinson's disease (PD) features the motor control deficits resulting from irreversible, progressive degeneration of dopaminergic (DA) neurons of the nigrostriatal pathway. Although intracerebral transplantation of human fetal ventral mesencephalon (hfVM) has been proven effective at reviving DA function in the PD patients, this treatment is clinically limited by availability of hfVM and the related ethical issues. Homologous tissues to hfVM, such as porcine fetal ventral mesencephalon (pfVM) thus present a strong clinical potential if immune response following xenotransplantation could be tamed. Olfactory ensheathing cells (OECs) are glial cells showing immunomodulatory properties. It is unclear but intriuging whether these properties can be applied to reducing immune response following neural xenotransplantation of PD. METHODS: To determine whether OECs may benefit neural xenografts for PD, different compositions of grafting cells were transplanted into striatum of the PD model rats. We used apomorphine-induced rotational behavior to evaluate effectiveness of the neural grafts on reviving DA function. Immunohistochemistry was applied to investigate the effect of OECs on the survival of neuroxenografts and underlying mechanisms of this effect. RESULTS: Four weeks following the xenotransplantation, we found that the PD rats receiving pfVM + OECs co-graft exhibited a better improvement in apomorphine-induced rotational behavior compared with those receiving only pfVM cells. This result can be explained by higher survival of DA neurons (tyrosine hydroxylase immunoreactivity) in grafted striatum of pfVM + OECs group. Furthermore, pfVM + OECs group has less immune response (CD3+ T cells and OX-6+ microglia) around the grafted area compared with pfVM only group. These results suggest that OECs may enhance the survival of the striatal xenografts via dampening the immune response at the grafted sites. CONCLUSIONS: Using allogeneic OECs as a co-graft material for xenogeneic neural grafts could be a feasible therapeutic strategy to enhance results and applicability of the cell replacement therapy for PD.


Assuntos
Xenoenxertos/imunologia , Mesencéfalo/transplante , Bulbo Olfatório/citologia , Doença de Parkinson/terapia , Transplante Heterólogo , Animais , Transplante de Células/métodos , Modelos Animais de Doenças , Dopamina/metabolismo , Transplante de Tecido Fetal/métodos , Masculino , Mesencéfalo/imunologia , Mesencéfalo/metabolismo , Doença de Parkinson/metabolismo , Ratos Sprague-Dawley , Transplante Heterólogo/métodos
5.
Oncotarget ; 9(15): 11922-11937, 2018 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-29552282

RESUMO

The small-molecule naphtha [2,3-f]quinoxaline-7,12-dione (NSC745887) can effectively inhibit the proliferation of various cancers by trapping DNA-topoisomerase cleavage. The aim of this study was to elucidate cellular responses of NSC745887 in human glioblastoma multiforme (GBM, U118MG and U87MG cells) and investigate the underlying molecular mechanisms. NSC745887 reduced the cell survival rate and increased the sub-G1 population in dose- and time-dependent manners in GBM cells. Moreover, NSC745887 increased expression of γH2AX and caused DNA fragmentation leading to DNA damage. Furthermore, Annexin V/propidium iodide and Br-dTP staining showed the apoptotic effect of NSC745887 in GBM cells. DNA repair proteins of ataxia-telangiectasia mutated (ATM), ATM and Rad3-related, and decoy receptor 3 also decreased with NSC745887 treatment. In addition, NSC745887 caused apoptosis by the caspase-8/9-caspase-3-poly(ADP-ribose) polymerase cascade. An in vivo study indicated that NSC745887 suppressed the [18F]-FDG-specific uptake value in brain tumors. Histological staining also indicated a decrease in Ki-67 and increases in γH2AX and cleaved caspase-3 in the brain tumor area. These data provide preclinical evidence for NSC745887 as a potential new small molecule drug for managing glioblastomas.

6.
J Tissue Eng Regen Med ; 11(7): 2024-2033, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-26510988

RESUMO

The pathology of Parkinson's disease (PD) results mainly from nigrostriatal pathway damage. Unfortunately, commonly used PD therapies do not repair the disconnected circuitry. It has been reported that using kainic acid (KA, an excitatory amino acid) in bridging transplantation may be useful to generate an artificial tract and reconstruct the nigrostriatal pathway in 6-hydroxydopamine (6-OHDA) lesioned rats. In this study, we used KA bridging and a co-graft of rat olfactory ensheathing cells (OECs) and rat E14 embryonic ventral mesencephalic (VM) tissue to restore the nigrostriatal pathway of the PD model rats. The methamphetamine-induced rotational behaviour, 4-[18 F]-ADAM (a selectively serotonin transporter radioligand)/micro-PET imaging, and immunohistochemistry were used to assess the effects of the transplantation. At 9 weeks post-grafting in PD model rats, the results showed that the PD rats undergoing VM tissue and OECs co-grafts (VM-OECs) exhibited better motor recovery compared to the rats receiving VM tissue transplantation only. The striatal uptake of 4-[18 F]-ADAM and tyrosine hydroxylase immunoreactivity (TH-ir) of the grafted area in the VM-OECs group were also more improved than those of the VM alone group. These results suggested that OECs may enhance the survival of the grafted VM tissue and facilitate the recovery of motor function after VM transplantation. Moreover, OECs possibly promote the elongation of dopaminergic and serotonergic axon in the bridging graft. Copyright © 2015 John Wiley & Sons, Ltd.


Assuntos
Mesencéfalo/transplante , Bulbo Olfatório/transplante , Doença de Parkinson Secundária/cirurgia , Animais , Masculino , Oxidopamina/efeitos adversos , Oxidopamina/farmacologia , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/patologia , Doença de Parkinson Secundária/fisiopatologia , Ratos , Ratos Sprague-Dawley
7.
Sci Rep ; 6: 38695, 2016 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-27941910

RESUMO

3,4-Methylenedioxymethamphetamine (MDMA), a common recreational drug, is known to cause serotonergic neurotoxicity in the brain. Dextromethorphan (DM) is a widely used antitussive reported to exert anti-inflammatory effect in vivo. In this study, we examined the long-term effect of MDMA on the primate serotonergic system and the protective property of DM against MDMA-induced serotonergic abnormality using single photon emission computed tomography (SPECT). Nine monkeys (Macaca cyclopis) were divided into three groups, namely control, MDMA and co-treatment (MDMA/DM). [123I]-ADAM was used as the radioligand for serotonin transporters (SERT) in SPECT scans. SERT levels of the brain were evaluated and presented as the uptake ratios (URs) of [123I]-ADAM in several regions of interest of the brain including midbrain, thalamus and striatum. We found that the URs of [123I]-ADAM were significantly lower in the brains of MDMA than control group, indicating lower brain SERT levels in the MDMA-treated monkeys. This MDMA-induced decrease in brain SERT levels could persist for over four years. However, the loss of brain SERT levels was not observed in co-treatment group. These results suggest that DM may exert a protective effect against MDMA-induced serotonergic toxicity in the brains of the non-human primate.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Cinanserina/análogos & derivados , Dextrometorfano/farmacologia , Serotonina/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Radioisótopos do Iodo , Imageamento por Ressonância Magnética , N-Metil-3,4-Metilenodioxianfetamina , Primatas , Fatores de Tempo , Tomografia Computadorizada de Emissão de Fóton Único
8.
Oncotarget ; 7(8): 8993-9006, 2016 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-26848771

RESUMO

Ovarian cancer treatment remains a challenge and targeting cancer stem cells presents a promising strategy. Niclosamide is an "old" antihelminthic drug that uncouples mitochondria of intestinal parasites. Although recent studies demonstrated that niclosamide could be a potential anticancer agent, its poor water solubility needs to be overcome before further preclinical and clinical investigations can be conducted. Therefore, we evaluated a novel nanosuspension of niclosamide (nano-NI) for its effect against ovarian cancer. Nano-NI effectively inhibited the growth of ovarian cancer cells in which it induced a metabolic shift to glycolysis at a concentration of less than 3 µM in vitro and suppressed tumor growth without obvious toxicity at an oral dose of 100 mg/kg in vivo. In a pharmacokinetic study after oral administration, nano-NI showed rapid absorption (reaching the maximum plasma concentration within 5 min) and improved the bioavailability (the estimated bioavailability for oral nano-NI was 25%). In conclusion, nano-NI has the potential to be a new treatment modality for ovarian cancer and, therefore, further clinical trials are warranted.


Assuntos
Antineoplásicos/farmacologia , Antineoplásicos/farmacocinética , Niclosamida/farmacologia , Niclosamida/farmacocinética , Neoplasias Ovarianas/tratamento farmacológico , Animais , Disponibilidade Biológica , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Metabolismo Energético/efeitos dos fármacos , Feminino , Glicólise/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Consumo de Oxigênio/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Suspensões/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Neurotoxicology ; 52: 114-26, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26610922

RESUMO

It has been suggested that autophagy plays pathogenetic roles in cerebral ischemia, brain trauma, and neurodegenerative disorders. 3,4-Methylenedioxymethamphetamine (MDMA or ecstasy) is an illicit drug that causes long-term serotonergic neurotoxicity in the brain. Apoptosis and necrosis have been implicated in MDMA-induced neurotoxicity, but the role of autophagy in MDMA-elicited serotonergic toxicity has not been investigated. The present study aimed to examine the contribution of autophagy to neurotoxicity in serotonergic neurons in in vitro and in vivo animal models challenged with MDMA. Here, we demonstrated that in cultured rat serotonergic neurons, MDMA exposure induced LC3B-densely stained autophagosome formation, accompanying by a decrease in neurite outgrowth. Autophagy inhibitor 3-methyladenine (3-MA) significantly attenuated MDMA-induced autophagosome accumulation, and ameliorated MDMA-triggered serotonergic neurite damage and neuron death. In contrast, enhanced autophagy flux by rapamycin or impaired autophagosome clearance by bafilomycin A1 led to more autophagosome accumulation in serotonergic neurons and aggravated neurite degeneration. In addition, MDMA-induced autophagy activation in cultured serotonergic neurons might be mediated by serotonin transporter (SERT). In an in vivo animal model administered MDMA, neuroimaging showed that 3-MA protected the serotonin system against MDMA-induced downregulation of SERT evaluated by animal-PET with 4-[(18)F]-ADAM, a SERT radioligand. Taken together, our results demonstrated that MDMA triggers upregulation of autophagy in serotonergic neurons, which appears to be detrimental to neuronal growth.


Assuntos
Autofagia/efeitos dos fármacos , N-Metil-3,4-Metilenodioxianfetamina/toxicidade , Degeneração Neural/patologia , Neurônios Serotoninérgicos/efeitos dos fármacos , Neurônios Serotoninérgicos/patologia , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Benzilaminas/metabolismo , Tronco Encefálico/efeitos dos fármacos , Células Cultivadas , Citalopram/farmacologia , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Radioisótopos de Flúor/metabolismo , Neuroimagem Funcional , Masculino , N-Metil-3,4-Metilenodioxianfetamina/antagonistas & inibidores , Degeneração Neural/induzido quimicamente , Neuritos/patologia , Fármacos Neuroprotetores/farmacologia , Fagossomos/metabolismo , Tomografia por Emissão de Pósitrons , Ratos , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo
10.
Eur Neuropsychopharmacol ; 26(1): 92-104, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26612383

RESUMO

The misuse of 3,4-methylenedioxymethamphetamine (MDMA) has drawn a growing concern worldwide for its psychophysiological impacts on humans. MDMA abusers are often accompanied by long-term serotonergic neurotoxicity, which is associated with reduced density of cerebral serotonin transporters (SERT) and depressive disorders. Resveratrol (RSV) is a natural polyphenolic phytoalexin that has been known for its antidepressant and neuroprotective effects. However, biological targets of RSV as well as its neuroprotective effects against MDMA remained largely unknown. In this study, we examined binding potency of RSV and MDMA to SERT using small-animal positron emission tomography (PET) with the SERT radioligand, N,N-dimethyl-2-(2-amino-4-[(18)F]fluorophenylthio)benzylamine (4-[(18)F]-ADAM) and investigated the protection of RSV against the acute and long-term adverse effects of MDMA. We found that RSV exhibit binding potentials to SERT in vivo in a dose-dependent manner with variation among brain regions. When the MDMA-treated rats (10mg/kg, s.c.) were co-injected with RSV (20mg/kg, i.p.) twice daily for 4 consecutive days, MDMA-induced acute elevation in plasma corticosterone was significantly reduced. Further, 4-[(18)F]-ADAM PET imaging revealed that RSV protected against the MDMA-induced decrease in SERT availability in the midbrain and the thalamus 2 weeks following the co-treatment. The PET data were comparable to the observation from the forced swim test that RSV sufficiently ameliorated the depressive-like behaviors of the MDMA-treated rats. Together, these findings suggest that RSV is a potential antidepressant and may confer protection against neurobiological and behavioral changes induced by MDMA.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , N-Metil-3,4-Metilenodioxianfetamina/toxicidade , Fármacos Neuroprotetores/farmacologia , Proteínas de Ligação a RNA/metabolismo , Estilbenos/farmacologia , Animais , Benzilaminas , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Corticosterona/sangue , Transtorno Depressivo/diagnóstico por imagem , Transtorno Depressivo/tratamento farmacológico , Transtorno Depressivo/metabolismo , Relação Dose-Resposta a Droga , Radioisótopos de Flúor , Masculino , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Distribuição Aleatória , Ratos Sprague-Dawley , Resveratrol , Serotoninérgicos/toxicidade
11.
Cell Transplant ; 25(2): 301-11, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25994923

RESUMO

Parkinson's disease (PD) is a neurodegenerative disease characterized by a loss of dopaminergic neurons in the nigrostriatal pathway. Apart from effective strategies to halt the underlying neuronal degeneration, cell replacement now offers novel prospects for PD therapy. Porcine embryonic neural tissue has been considered an alternative source to human fetal grafts in neurodegenerative disorders because its use avoids major practical and ethical issues. This study was undertaken to evaluate the effects of embryonic day 27 (E27) porcine mesencephalic tissue transplantation in a PD rat model using animal positron emission tomography (PET) coupled with 4-[(18)F]-ADAM, a serotonin transporter (SERT) imaging agent. The parkinsonian rat was induced by injecting 6-hydroxydopamine into the medial forebrain bundle (MFB) of the right nigrostriatal pathway. The apomorphine-induced rotation behavioral test and 4-[(18)F]-ADAM/animal PET scanning were carried out following 6-OHDA lesioning. At the second week following 6-OHDA lesioning, the parkinsonian rat rotates substantially on apomorphine-induced contralateral turning. In addition, the mean striatal-specific uptake ratio (SUR) of 4-[(18)F]-ADAM decreased by 44%. After transplantation, the number of drug-induced rotations decreased markedly, and the mean SUR of 4-[(18)F]-ADAM and the level of SERT immunoreactivity (SERT-ir) in striatum were partially restored. The mean SUR level was restored to 71% compared to that for the contralateral intact side, which together with the abundant survival of tyrosine hydroxylase (TH) neurons accounted for functional recovery at the fourth week postgraft. In regard to the extent of donor-derived cells, we found the neurons of the xenografts from E27 transgenic pigs harboring red fluorescent protein (RFP) localized with TH-ir cells and SERT-ir in the grafted area. Thus, transplanted E27 porcine mesencephalic tissue may restore dopaminergic and serotonergic systems in the parkinsonian rat. The 4-[(18)F]-ADAM/animal PET can be used to detect serotonergic neuron loss in PD and monitor the efficacy of therapy.


Assuntos
Apomorfina/farmacologia , Degeneração Neural/patologia , Doença de Parkinson/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Animais , Corpo Estriado/patologia , Modelos Animais de Doenças , Dopamina/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Masculino , Oxidopamina/farmacologia , Doença de Parkinson/patologia , Tomografia por Emissão de Pósitrons/métodos , Ratos Sprague-Dawley , Substância Negra/efeitos dos fármacos , Substância Negra/patologia , Suínos , Transplante Heterólogo
12.
PLoS One ; 10(9): e0138431, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26378923

RESUMO

3,4-Methylenedioxymethamphetamine (MDMA), also known as "Ecstasy", is a common recreational drug of abuse. Several previous studies have attributed the central serotonergic neurotoxicity of MDMA to distal axotomy, since only fine serotonergic axons ascending from the raphe nucleus are lost without apparent damage to their cell bodies. However, this axotomy has never been visualized directly in vivo. The present study examined the axonal integrity of the efferent projections from the midbrain raphe nucleus after MDMA exposure using in vivo manganese-enhanced magnetic resonance imaging (MEMRI). Rats were injected subcutaneously six times with MDMA (5 mg/kg) or saline once daily. Eight days after the last injection, manganese ions (Mn2+) were injected stereotactically into the raphe nucleus, and a series of MEMRI images was acquired over a period of 38 h to monitor the evolution of Mn2+-induced signal enhancement across the ventral tegmental area, the medial forebrain bundle (MFB), and the striatum. The MDMA-induced loss of serotonin transporters was clearly evidenced by immunohistological staining consistent with the Mn2+-induced signal enhancement observed across the MFB and striatum. MEMRI successfully revealed the disruption of the serotonergic raphe-striatal projections and the variable effect of MDMA on the kinetics of Mn2+ accumulation in the MFB and striatum.


Assuntos
Núcleo Dorsal da Rafe/efeitos dos fármacos , Manganês/metabolismo , N-Metil-3,4-Metilenodioxianfetamina/farmacologia , Prosencéfalo/metabolismo , Animais , Axônios/efeitos dos fármacos , Axônios/metabolismo , Axotomia/métodos , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Imageamento por Ressonância Magnética/métodos , Masculino , Síndromes Neurotóxicas/metabolismo , Ratos , Ratos Sprague-Dawley , Serotonina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Área Tegmentar Ventral/efeitos dos fármacos , Área Tegmentar Ventral/metabolismo
13.
Cytotherapy ; 16(10): 1371-83, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24996595

RESUMO

BACKGROUND AIMS: The purpose of this study was to examine neurotrophic and neuroprotective effects of limbus stroma-derived mesenchymal stromal cells (L-MSCs) on cortical neurons in vitro and in vivo. METHODS: Cultured L-MSCs were characterized by flow cytometry and immunofluorescence through the use of specific MSC marker antibodies. Conditioned media were collected from normoxia- and hypoxia-treated L-MSCs to assess neurotrophic effects. Neuroprotective potentials were evaluated through the use of in vitro hypoxic cortical neuron culture and in vivo rat focal cerebral ischemia models. Neuronal morphology was confirmed by immunofluorescence with the use of anti-MAP2 antibody. Post-ischemic infarct volume and motor behavior were assayed by means of triphenyltetrazolium chloride staining and open-field testing, respectively. Human growth antibody arrays and enzyme-linked immunoassays were used to analyze trophic/growth factors contained in conditioned media. RESULTS: Isolated human L-MSCs highly expressed CD29, CD90 and CD105 but not CD34 and CD45. Mesenchymal lineage cell surface expression pattern and differentiation capacity were identical to MSCs derived form human bone marrow and adipose tissue. The L-MSC normoxic and hypoxic conditioned media both promoted neurite outgrowth in cultured cortical neurons. Hypoxic conditioned medium showed superior neurotrophic function and neuroprotective potential with reduced ischemic brain injury and improved functional recovery in rat focal cerebral ischemia models. Human growth factor arrays and enzyme-linked immunoassays measurements showed neuroprotective and growth-associated cytokines (vascular endothelial growth factor [VEGF], VEGFR3, brain-derived neurotrophic factor, insulin-like growth factor -2 and hepatocyte growth factor) contained in conditioned media. Hypoxic exposure caused VEGF and brain-derived neurotrophic factor upregulation, possibly contributing to neurotrophic and neuroprotective effects. CONCLUSIONS: L-MSCs can secrete various neurotrophic factors stimulating neurite outgrowth and protecting neurons against brain ischemic injury through paracrine mechanism.


Assuntos
Isquemia Encefálica/terapia , Limbo da Córnea/citologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Neurogênese , Animais , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Humanos , Masculino , Fatores de Crescimento Neural/metabolismo , Fatores de Crescimento Neural/farmacologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Fármacos Neuroprotetores/metabolismo , Fármacos Neuroprotetores/farmacologia , Ratos , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio Vascular/metabolismo
14.
PLoS One ; 9(12): e116565, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25551657

RESUMO

Autophagic (type II) cell death, characterized by the massive accumulation of autophagic vacuoles in the cytoplasm of cells, has been suggested to play pathogenetic roles in cerebral ischemia, brain trauma, and neurodegenerative disorders. 3,4-Methylenedioxymethamphetamine (MDMA or ecstasy) is an illicit drug causing long-term neurotoxicity in the brain. Apoptotic (type I) and necrotic (type III) cell death have been implicated in MDMA-induced neurotoxicity, while the role of autophagy in MDMA-elicited neurotoxicity has not been investigated. The present study aimed to evaluate the occurrence and contribution of autophagy to neurotoxicity in cultured rat cortical neurons challenged with MDMA. Autophagy activation was monitored by expression of microtubule-associated protein 1 light chain 3 (LC3; an autophagic marker) using immunofluorescence and western blot analysis. Here, we demonstrate that MDMA exposure induced monodansylcadaverine (MDC)- and LC3B-densely stained autophagosome formation and increased conversion of LC3B-I to LC3B-II, coinciding with the neurodegenerative phase of MDMA challenge. Autophagy inhibitor 3-methyladenine (3-MA) pretreatment significantly attenuated MDMA-induced autophagosome accumulation, LC3B-II expression, and ameliorated MDMA-triggered neurite damage and neuronal death. In contrast, enhanced autophagy flux by rapamycin or impaired autophagosome clearance by bafilomycin A1 led to more autophagosome accumulation in neurons and aggravated neurite degeneration, indicating that excessive autophagosome accumulation contributes to MDMA-induced neurotoxicity. Furthermore, MDMA induced phosphorylation of AMP-activated protein kinase (AMPK) and its downstream unc-51-like kinase 1 (ULK1), suggesting the AMPK/ULK1 signaling pathway might be involved in MDMA-induced autophagy activation.


Assuntos
3,4-Metilenodioxianfetamina/análogos & derivados , Autofagia/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurotoxinas/toxicidade , 3,4-Metilenodioxianfetamina/toxicidade , Proteínas Quinases Ativadas por AMP/metabolismo , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Proteína Homóloga à Proteína-1 Relacionada à Autofagia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
15.
Oncotarget ; 4(12): 2366-82, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24280306

RESUMO

Spheroid formation is one property of stem cells-such as embryo-derived or neural stem cells-that has been used for the enrichment of cancer stem-like cells (CSLCs). However, it is unclear whether CSLC-derived spheroids are heterogeneous or whether they share common embryonic stemness properties. Understanding these features might lead to novel therapeutic approaches. Ovarian carcinoma is a deadly disease of women. We identified two types of spheroids (SR1 and SR2) from ovarian cancer cell lines and patients' specimens according to their morphology. Both types expressed stemness markers and could self-renew and initiate tumors when a low number of cells were used. Only SR1 could differentiate into multiple-lineage cell types under specific induction conditions. SR1 spheroids could differentiate to SR2 spheroids through epithelial-mesenchymal transition. Alkaline phosphatase (ALP) was highly expressed in SR1 spheroids, decreased in SR2 spheroids, and was absent in differentiated progenies in accordance with the loss of stemness properties. We verified that ALP can be a marker for ovarian CSLCs, and patients with greater ALP expression is related to advanced clinical stages and have a higher risk of recurrence and lower survival rate. The ALP inhibitor, levamisole, disrupted the self-renewal of ovarian CSLCs in vitro and tumor growth in vivo. In summary, this research provides a plastic ovarian cancer stem cell model and a new understanding of the cross-link between stem cells and cancers.This results show that ovarian CSLCs can be suppressed by levamisole. Our findings demonstrated that some ovarian CSLCs may restore ALP activity, and this suggests that inhibition of ALP activity may present a new opportunity for treatment of ovarian cancer.


Assuntos
Fosfatase Alcalina/antagonistas & inibidores , Neoplasias Epiteliais e Glandulares/tratamento farmacológico , Neoplasias Epiteliais e Glandulares/enzimologia , Células-Tronco Neoplásicas/patologia , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/enzimologia , Adolescente , Adulto , Idoso , Fosfatase Alcalina/metabolismo , Carcinoma Epitelial do Ovário , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Processos de Crescimento Celular/efeitos dos fármacos , Processos de Crescimento Celular/genética , Linhagem Celular Tumoral , Linhagem da Célula , Transição Epitelial-Mesenquimal , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Epiteliais e Glandulares/patologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/enzimologia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Esferoides Celulares , Adulto Jovem
16.
Cell Transplant ; 22(7): 1295-305, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23127756

RESUMO

This study was undertaken to address the effects of fetal mesencephalic tissue transplantation on the serotonin system in a rat model of Parkinson's disease (PD) while also investigating the usefulness of 4-[18F]-ADAM (a serotonin transporter imaging agent) coupled with micro-PET for imaging serotonin transporters (SERTs). A PD model was induced by unilateral injection of 6-hydroxydopamine (6-OHDA) into the right medial forebrain bundle of the nigrostriatal pathway, while cell transplantation was performed via intrastriatal injection of mesencephalic brain tissue dissected from embryonic (E14) rats. The 4-[18F]-ADAM/micro-PET scanning was performed following both 6-OHDA lesioning and transplantation. Immunohistochemistry (IHC) studies were also performed following the final PET scan, and the results were compared to show a 17-43% decrease in the specific uptake ratio (SUR) and a 23-52% decrease in serotonin transporter immunoreactivity (SERT-ir) within various brain regions on the lesioned side. The number of methamphetamine-induced rotations also decreased significantly at the 4th week postgraft. In addition, striatal SUR and the SERT-ir levels were restored to 77% and 83% 5 weeks postgraft. These results suggest that Parkinson's disease also affects the serotonergic system, while both the dopaminergic and serotonergic systems can be partially restored in a rat model of PD after E14 mesencephalic tissue transplantation. In addition, we have also determined that 4-[18F]-ADAM/micro-PET can be used to detect serotonergic neuron loss, monitor the progress of Parkinson's disease, and oversee the effectiveness of therapy.


Assuntos
Proteínas ADAM/química , Doença de Parkinson/diagnóstico por imagem , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Proteínas ADAM/metabolismo , Proteínas ADAM/farmacologia , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Modelos Animais de Doenças , Neurônios Dopaminérgicos/fisiologia , Radioisótopos de Flúor/química , Imuno-Histoquímica , Masculino , Mesencéfalo/citologia , Mesencéfalo/transplante , Razão de Chances , Oxidopamina/farmacologia , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Tomografia por Emissão de Pósitrons , Ratos , Ratos Sprague-Dawley , Neurônios Serotoninérgicos/fisiologia , Transplante Homólogo
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