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1.
Braz. j. biol ; 82: e236297, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1153472

RESUMO

Abstract Plectranthus barbatus Andrews (Lamiaceae) is widely distributed in the world and has a range of popular therapeutic indications. This work aimed to evaluate the phytochemical characterization of two leaf extracts of P. barbatus, and their antimicrobial, antineoplastic and immunomodulatory potential. After collection, herborization and obtainment of the P. barbatus aqueous extract (PBA) and acetone:water 7:3 P. barbatus organic extract (PBO), the phytochemical characterization was performed by high-performance liquid chromatography (HPLC). The antimicrobial activity was performed to determine the minimum inhibitory concentration (MIC) against eight bacterial strains using the microdilution test and the fungus Trichophyton rubrum by disc diffusion assay and microdilution test. Cytotoxicity was assessed by MTT and trypan blue methods in normal peripheral blood mononuclear cells (PBMCs) at concentrations ranged between 0.1 to 100 µg.mL-1 and in neoplastic cell lines Toledo, K562, DU-145 and PANC-1 at 1, 10 and 100 µg.mL-1 . Immunomodulatory activity, was evaluated by sandwich ELISA of proinflammatory cytokines at BALB/c mice splenocytes cultures supernatant. Both extracts presented flavonoids, cinnamic derivatives, steroids and ellagic acid. PBO showed bacteriostatic activity against Acinetobacter baumannii (MIC = 250 µg.mL-1) clinical isolate and PBA fungistatic activity against Trichophyton rubrum (MIC = 800 µg.mL-1). The extracts did not exhibit toxicity to PBMCs and neoplastic cells (IC50 > 100 µg.mL-1). Additionally, PBO at 100 µg.mL-1 significantly inhibited IFN-γ and IL-17A cytokines (p = 0.03). Plectranthus barbatus is a potential candidate for therapeutic use due to its low toxicity in healthy human cells and exhibits biological activities of medical interest as bacteriostatic, fungistatic and immunomodulatory.


Resumo Plectranthus barbatus Andrews (Lamiaceae) é amplamente distribuída no mundo e com uma série de indicações terapêuticas populares. Este trabalho teve como objetivo avaliar a caracterização fitoquímica de dois extratos da folha de P. barbatus e seu potencial antimicrobiano, antineoplásico e imunomodulador. Após coleta, herborização e obtenção do extrato aquoso (PBA) e acetona: água 7: 3 (orgânico) (PBO) de P. barbatus, a caracterização fitoquímica foi realizada por cromatografia líquida de alta eficiência (CLAE). A atividade antimicrobiana foi realizada para determinar a concentração inibitória mínima (CIM) contra oito cepas bacterianas usando o teste de microdiluição e o fungo Trichophyton rubrum por ensaio de difusão em disco e teste de microdiluição. A citotoxicidade foi avaliada por métodos MTT e azul de tripan em células normais mononucleares do sangue periférico (CMSP) em concentrações variadas entre 0,1 a 100 µg.mL-1 e nas linhagens celulares neoplásicas Toledo, K562, DU-145 e PANC-1 em 1, 10 e 100 µg.mL-1 . A atividade imunomoduladora foi avaliada por ELISA sanduíche de citocinas pró-inflamatórias em sobrenadante de culturas de esplenócitos de camundongos BALB/c. Ambos os extratos apresentaram flavonoides, derivados cinâmicos, esteróides e ácido elágico. O PBO mostrou atividade bacteriostática contra Acinetobacter baumannii (CIM = 250 µg.mL-1) e atividade fungistática do PBA contra Trichophyton rubrum (CIM = 800 µg.mL-1). Os extratos não apresentaram toxicidade para CMSP e células neoplásicas (IC50 > 100 µg.mL-1). Além disso, o PBO a 100 µg.mL-1 inibiu significativamente as citocinas IFN-γ e IL-17A (p = 0,03). Plectranthus barbatus é um candidato potencial para uso terapêutico devido à sua baixa toxicidade em células humanas saudáveis ​​e exibe atividade de interesse médico como bacteriostática, fungistática e imunomoduladora.

2.
Braz J Biol ; 82: e236297, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33787716

RESUMO

Plectranthus barbatus Andrews (Lamiaceae) is widely distributed in the world and has a range of popular therapeutic indications. This work aimed to evaluate the phytochemical characterization of two leaf extracts of P. barbatus, and their antimicrobial, antineoplastic and immunomodulatory potential. After collection, herborization and obtainment of the P. barbatus aqueous extract (PBA) and acetone:water 7:3 P. barbatus organic extract (PBO), the phytochemical characterization was performed by high-performance liquid chromatography (HPLC). The antimicrobial activity was performed to determine the minimum inhibitory concentration (MIC) against eight bacterial strains using the microdilution test and the fungus Trichophyton rubrum by disc diffusion assay and microdilution test. Cytotoxicity was assessed by MTT and trypan blue methods in normal peripheral blood mononuclear cells (PBMCs) at concentrations ranged between 0.1 to 100 µg.mL-1 and in neoplastic cell lines Toledo, K562, DU-145 and PANC-1 at 1, 10 and 100 µg.mL-1 . Immunomodulatory activity, was evaluated by sandwich ELISA of proinflammatory cytokines at BALB/c mice splenocytes cultures supernatant. Both extracts presented flavonoids, cinnamic derivatives, steroids and ellagic acid. PBO showed bacteriostatic activity against Acinetobacter baumannii (MIC = 250 µg.mL-1) clinical isolate and PBA fungistatic activity against Trichophyton rubrum (MIC = 800 µg.mL-1). The extracts did not exhibit toxicity to PBMCs and neoplastic cells (IC50 > 100 µg.mL-1). Additionally, PBO at 100 µg.mL-1 significantly inhibited IFN-γ and IL-17A cytokines (p = 0.03). Plectranthus barbatus is a potential candidate for therapeutic use due to its low toxicity in healthy human cells and exhibits biological activities of medical interest as bacteriostatic, fungistatic and immunomodulatory.


Assuntos
Plectranthus , Animais , Arthrodermataceae , Leucócitos Mononucleares , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia
3.
Brain Res ; 1746: 147007, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32645380

RESUMO

Cerebrovascular diseases are currently a major global health problem. Considering the limitations of current therapy, the search for new alternatives for the treatment of these diseases is necessary and, in this context, curcumin, a molecule that has neuroprotective properties already described in the literature. A limiting factor when considering therapies for the nervous tissue is the presence of the blood-brain barrier which stimulates the search for new drug delivery strategies. In this context, nanoencapsulation seems to be a promising alternative. In this work, we compared the protective effects of free and nanoemulsified curcumin after intracerebral haemorrhage induced by collagenase (ICH) in Wistar rats. Injury area, motor activity, oxidative stress in the brain and serum biochemical parameters were investigated. Two hours after surgery, the first dose was injected intraperitoneally, followed by 24 and 48 h administration. Behavioural analysis was performed through 3 different tests: open field, beam walking and foot fault (24, 48 and 72 h respectively). At the end of the recovering time (3 days after injury), the animals were euthanized and the brain (for analysis of injury area and oxidative stress), blood (for biochemical parameters), kidney and liver (for histopathological examination) were investigated. Curcumin nanoemulsion 30 mg/kg was able to improve behavioural recovery, reduce the size of the haematoma and attenuate the weight loss caused by ICH. In terms of oxidative parameters, we observed that curcumin nanoemulsion modulated antioxidant responses with therapeutic potential against ICH. Only discrete results in few parameters were found with free-curcumin in the same dose.

4.
Arq. bras. med. vet. zootec. (Online) ; 72(1): 25-32, Jan.-Feb. 2020. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-1088924

RESUMO

A fim de avaliar o efeito de diferentes doses da rbST sobre a dinâmica folicular, a produção e a maturação in vitro de oócitos, 20 vacas Sindi, divididas em três grupos, receberam um dispositivo de progesterona intravaginal, estradiol e PGF2α, além de 2mL de solução salina (grupo controle), 250 (grupo rbST 250) ou 500mg de rbST (grupo rbST 500). Cinco dias depois, realizou-se a ovum pick up, e os complexos cumulus-oócitos (CCOs) recuperados foram selecionados, classificados e maturados in vitro. Os dados de contagem foram comparados pelo procedimento glht (General Linear Hypothesis Test), e os dados em porcentagem foram submetidos ao qui-quadrado, no programa estatístico R, onde as diferenças foram consideradas significativas quando P<0,05. Não houve diferença (P>0,05) entre os grupos quanto à quantidade de folículos e à taxa de maturação. Os grupos rbST 250 e rbST 500 foram significativamente superiores (P<0,05) ao grupo controle em relação ao número de folículos grandes (0,42±0,20 vs. 0). O grupo rbST 500 apresentou maior (P<0,05) porcentagem de oócitos viáveis (91,52%) do que os grupos controle (67,85%) e rbST 250 (53,33%). A rbST aumenta o número de folículos grandes, e 500mg de rbST aumentam a porcentagem de oócitos viáveis em vacas Sindi.(AU)


In order to evaluate the effect of different doses of rbST on the follicular dynamics, production, and in vitro maturation of oocytes, 20 Sindhi cows were divided into three groups, receiving an intravaginal progesterone device, estradiol and PGF2α, and 2mL of solution saline (Control Group), 250 (rbST 250 Group) or 500mg rbST (rbST 500 Group). Five days later, the ovum pick up was performed, and the cumulus-oocyte (CCO) complexes recovered were selected, classified, and matured in vitro. The counting data were compared by the glht (General Linear Hypothesis Test) procedure, and the percentage data were submitted to Qui- square, in the statistical program R, where differences were considered significant when P< 0.05. There was no difference (P> 0.05) between the groups regarding follicle quantity and maturation rate. The rbST 250 and rbST 500 groups were significantly higher (P< 0.05) than the Control group in relation to the number of large follicles (0.42±0.20 versus 0). The rbST 500 group presented higher (P< 0.05) percentage of viable oocytes (91.52%) than the Control (67.85%) and rbST 250 (53.33%) groups. rbST increases the number of large follicles and 500mg rbST increases the percentage of viable oocytes in Sindhi cows.(AU)


Assuntos
Animais , Feminino , Bovinos , Oócitos , Indução da Ovulação/veterinária , Hormônio do Crescimento/administração & dosagem , Técnicas de Maturação in Vitro de Oócitos/veterinária
6.
Arq. bras. med. vet. zootec. (Online) ; 71(2): 464-472, mar.-abr. 2019. tab, ilus
Artigo em Português | LILACS, VETINDEX | ID: biblio-1011253

RESUMO

A fim de se avaliar o uso do óleo essencial de Croton nepetifolius Baill (OECn) na penetrabilidade cervical em ovelhas mestiças, 40 ovelhas foram distribuídas ao acaso em quatro grupos (n=10): controle, misoprostol, OECn50 e OECn100 (50 e 100µg do OECn, respectivamente). Após a sincronização do estro, utilizando CIDR e eCG (200UI), a profundidade de penetração da cérvix foi mensurada utilizando-se uma pipeta de inseminação artificial de bovino graduada, no período de zero até 72h após a retirada do CIDR. Os resultados foram expressos em média ± erro-padrão, submetidos à ANOVA seguida do teste de Tukey, enquanto os dados, em porcentagem, foram submetidos aos testes de Fisher ouqui-quadrado. Nenhuma diferença significativa (P>0,05) foi encontrada quanto ao grau de penetrabilidade cervical. Quanto ao tempo de passagem, os grupos misoprostol e OECn100 apresentaram um menor tempo de penetrabilidade às 60h(1,7±0,6 e 1,5±0,6min, respectivamente), quando comparados ao grupo controle (4,1±0,6min), que não diferiu significativamente do grupo OECn50 (2,3±0,6min). Portanto, o óleo essencial de Croton nepetifolius Baill pode ser utilizado para encurtar o tempo de penetrabilidade cervical em ovelhas submetidas à sincronização estral.(AU)


In order to evaluate the use of the essential oil of Croton nepetifolius Baill (EOCn) on cervical penetration in crossbred ewes, 40 ewes were randomly allocated into four groups (n= 10): CONTROL, MISOPROSTOL, EOCn50 and EOCn100 (50 e 100µg of the EOCn, respectively). After estrus synchronization, using CIDR and eCG (200IU), depth of cervical penetration was measured using artificial insemination gun for bovine species which was graduated and used from 0 to 72h after CIDR removal. Results were expressed as mean ± standard error mean, submitted to ANOVA and Tukey test while data in percentage were submitted to Fisher or Chi-Square test. No significant difference (P> 0.05) was observed at grade of cervical penetration. Concerning trespassing time, MISOPROTOL and EOCn100 groups presented a lower trespassing time at 60h (1.7±0.6 and 1.5±0.6min, respectively) than CONTROL group (4.1±0.6min), which did not differ significantly from EOCn50 (2.3±0.6min) group. Therefore, the essential oil of Croton nepetifolius Baill can be used to shorten the cervical penetration time in estrus synchronized ewes.(AU)


Assuntos
Animais , Feminino , Gravidez , Estro , Ovinos , Euphorbiaceae , Parto , Sincronização do Estro
7.
J Control Release ; 297: 26-38, 2019 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-30664980

RESUMO

Glaucoma is a multifactorial neurodegenerative disorder and one of the leading causes of irreversible blindness globally and for which intraocular pressure is the only modifiable risk factor. Although neuroprotective therapies have been suggested to have therapeutic potential, drug delivery for the treatment of ocular disorders such as glaucoma remains an unmet clinical need, further complicated by poor patient compliance with topically applied treatments. In the present study we describe the development of multi-loaded PLGA-microspheres (MSs) incorporating three recognised neuroprotective agents (dexamethasone (DX), melatonin (MEL) and coenzyme Q10 (CoQ10)) in a single formulation (DMQ-MSs) to create a novel sustained-release intraocular drug delivery system (IODDS) for the treatment of glaucoma. MSs were spherical, with a mean particle size of 29.04 ±â€¯1.89 µm rendering them suitable for intravitreal injection using conventional 25G-32G needles. >62% incorporation efficiency was achieved for the three drug cargo and MSs were able to co-deliver the encapsulated active compounds in a sustained manner over 30-days with low burst release. In vitro studies showed DMQ-MSs to be neuroprotective in a glutamate-induced cytotoxicity model (IC50 10.00 ±â€¯0.94 mM versus 6.89 ±â€¯0.82 mM in absence of DMQ-MSs) in R28 cell line. In vivo efficacy studies were performed using a well-established rodent model of chronic ocular hypertension (OHT), comparing single intravitreal injections of microspheres of DMQ-MSs to their equivalent individual single-drug loaded MSs mixture (MSsmix), empty MSs, no-treatment OHT only and naïve groups. Twenty one days after OHT induction, DMQ-MSs showed a significantly neuroprotective effect on RGCs compared to OHT only controls. No such protective effect was observed in empty MSs and single-drug MSs treated groups. This work suggests that multi-loaded PLGA MSs present a novel therapeutic approach in the management of retinal neurodegeneration conditions such as glaucoma.


Assuntos
Portadores de Fármacos/química , Glaucoma/tratamento farmacológico , Microesferas , Fármacos Neuroprotetores/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Animais , Dexametasona/administração & dosagem , Dexametasona/química , Modelos Animais de Doenças , Composição de Medicamentos , Liberação Controlada de Fármacos , Quimioterapia Combinada/métodos , Humanos , Injeções Intraoculares , Masculino , Melatonina/administração & dosagem , Melatonina/química , Fármacos Neuroprotetores/administração & dosagem , Ratos , Retina/efeitos dos fármacos , Fator de Transcrição Brn-3B/metabolismo , Resultado do Tratamento , Ubiquinona/administração & dosagem , Ubiquinona/análogos & derivados , Ubiquinona/química
9.
Zygote ; 26(6): 465-470, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30767819

RESUMO

SummaryThe present study aimed to investigate the effect of quercetin as an alternative antioxidant to cysteamine on in vitro maturation. Oocytes were collected from goat ovaries, destined for in vitro maturation and distributed into three groups: CIS group, oocytes were immersed in MIV base medium; in Groups Q4 and Q8, oocytes were immersed in the medium of the CIS group, adding 4 µM or 8 µM of quercetin, respectively, and cultured for 24 h at 38.5°C with 5% CO2. The CIS and Q4 groups presented the same percentage of expanded cumulus cells, but the per cent in the Q8 group was significantly lower than that of the other groups (P<0.05). The oocyte retraction rate in the Q8 group was higher (P<0.05) than in the CIS and Q4 groups. Treatment with 8 µM of quercetin presented a lower proportion of expanded oocytes than the CIS group and 4 µM of quercetin (P<0.05). The percentage of MII oocytes was higher in the Q4 group than in the CIS group (P<0.05), but the percentages in the CIS and Q8 groups were similar. The rate of apoptosis was higher in the CIS group than in the other groups (P<0.05). In addition, oocytes matured with 4 µM quercetin showed higher mitochondrial activity than matured oocytes in the CIS and Q8 groups (P<0.05). In conclusion, 4 µM of quercetin can be used as an alternative to cysteamine in the in vitro maturation of goat oocytes.


Assuntos
Técnicas de Maturação in Vitro de Oócitos/métodos , Mitocôndrias/efeitos dos fármacos , Oócitos/efeitos dos fármacos , Oócitos/fisiologia , Quercetina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Cromatina/efeitos dos fármacos , Cromatina/ultraestrutura , Células do Cúmulo , Fragmentação do DNA/efeitos dos fármacos , Glutationa/metabolismo , Cabras , Mitocôndrias/metabolismo , Quercetina/administração & dosagem , Espécies Reativas de Oxigênio/metabolismo
10.
Int Ophthalmol ; 37(6): 1311-1317, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27990622

RESUMO

PURPOSE: To compare the refractive outcome of eyes that underwent phacoemulsification combined with endoscopic cyclophotocoagulation (phaco-ECP) with the eyes that underwent phacoemulsification alone. METHODS: A retrospective case series review of 103 consecutive eyes that underwent phaco-ECP and 62 eyes that underwent phacoemulsification between January 2006 and August 2012 was conducted. Post-operative refractive outcomes were obtained by subjective refraction or autorefraction. Demographic data, best corrected visual acuity, intraocular pressure, number of glaucoma agents and mean deviation of the Humphrey visual field test (MD) were also analysed. RESULTS: The total number of eyes included in the study was 62 eyes for the phaco-ECP group and 62 eyes for the control group who underwent phacoemulsification alone. More than 90% of eyes (n = 56) in phaco-ECP group achieved post-operative refraction within ±1 dioptre (D) of the target refraction. In the control group, 100% of eyes achieved post-operative refraction within ±1D of the target refraction. When comparing the difference between the target and the actual refractive outcome between the phaco-ECP and the control group, there was no statistically significant difference. CONCLUSIONS: Refractive outcome after phaco-ECP is comparable to phacoemulsification alone. This study suggests that the intraocular lens power can be selected for cataract surgery alone and that ECP does not change the effective lens position significantly; therefore, no modification of biometry formulae is required. Phaco-ECP should be considered as an effective, safe and predictable surgical treatment option for glaucoma patients with co-existing cataract.


Assuntos
Glaucoma/cirurgia , Fotocoagulação a Laser/métodos , Facoemulsificação , Erros de Refração/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Feminino , Glaucoma/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Refração Ocular/fisiologia , Estudos Retrospectivos
11.
Cell Death Discov ; 2: 16031, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27551521

RESUMO

Secondary neurodegeneration is thought to play an important role in the pathology of neurodegenerative disease, which potential therapies may target. However, the quantitative assessment of the degree of secondary neurodegeneration is difficult. The present study describes a novel algorithm from which estimates of primary and secondary degeneration are computed using well-established rodent models of partial optic nerve transection (pONT) and ocular hypertension (OHT). Brn3-labelled retinal ganglion cells (RGCs) were identified in whole-retinal mounts from which RGC density, nearest neighbour distances and regularity indices were determined. The spatial distribution and rate of RGC loss were assessed and the percentage of primary and secondary degeneration in each non-overlapping segment was calculated. Mean RGC number (82 592±681) and RGC density (1695±23.3 RGC/mm(2)) in naïve eyes were comparable with previous studies, with an average decline in RGC density of 71±17 and 23±5% over the time course of pONT and OHT models, respectively. Spatial analysis revealed greatest RGC loss in the superior and central retina in pONT, but significant RGC loss in the inferior retina from 3 days post model induction. In comparison, there was no significant difference between superior and inferior retina after OHT induction, and RGC loss occurred mainly along the superior/inferior axis (~30%) versus the nasal-temporal axis (~15%). Intriguingly, a significant loss of RGCs was also observed in contralateral eyes in experimental OHT. In conclusion, a novel algorithm to automatically segment Brn3a-labelled retinal whole-mounts into non-overlapping segments is described, which enables automated spatial and temporal segmentation of RGCs, revealing heterogeneity in the spatial distribution of primary and secondary degenerative processes. This method provides an attractive means to rapidly determine the efficacy of neuroprotective therapies with implications for any neurodegenerative disorder affecting the retina.

13.
Nanotechnology ; 27(17): 175101, 2016 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-26965041

RESUMO

Intracerebral haemorrhage (ICH) is a worldwide public health problem. Experimental studies have shown that oxidative stress plays an important role in the pathogenesis of ICH and could represent a target for its treatment. However, the blood-brain barrier is an obstacle to be overcome, as it hampers the administration of compounds to the central nervous system. In this study, we compared the effects of a quercetin-loaded nanoemulsion (QU-N) with the free form of the drug (QU-SP) in a collagenase-induced ICH rat model. Quercetin (QU) is a polyphenol that has an antioxidant effect in vitro, but due to its high lipophilicity, it has low bioavailability in vivo. In this study, animals submitted or not to ICH were treated with a single intraperitoneal QU dose (free or nanoemulsion) of 30 mg kg(-1). Motor assessment was evaluated by the open field, foot fault and beam walking behavioural tests. 72 h after surgery the haematoma size was evaluated and biochemical measurements were performed. Animals treated with QU-N had a significant improvement in the beam walking and open field tests. Also, QU-N was able to reduce the size of the haematoma, preserving the activity of glutathione S-transferase (GST), increasing GSH content, and the total antioxidant capacity. QU-SP recovered locomotor activity and increased the GSH content and the total antioxidant capacity. Thus, it can be observed that QU presented antioxidant activity in both formulations, but the incorporation into nanoemulsions increased its antioxidant effect, which was reflected in the improvement of the motor skills and in the haematoma size decrement. These results suggest that the nanoemulsion containing QU developed in this study could be promising for future studies on treatments for ICH.


Assuntos
Antioxidantes/administração & dosagem , Hemorragia Cerebral/tratamento farmacológico , Portadores de Fármacos/química , Nanoestruturas/química , Quercetina/química , Animais , Antioxidantes/química , Antioxidantes/farmacologia , Peso Corporal/efeitos dos fármacos , Hemorragia Cerebral/etiologia , Cromatografia Líquida de Alta Pressão , Colagenases/metabolismo , Modelos Animais de Doenças , Emulsões/química , Glutationa/metabolismo , Glutationa Transferase/metabolismo , Locomoção/efeitos dos fármacos , Tamanho da Partícula , Quercetina/administração & dosagem , Quercetina/farmacologia , Ratos , Ratos Wistar
14.
Eye (Lond) ; 29(10): 1260-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26293138

RESUMO

Glaucoma is one of the leading causes of blindness worldwide and will affect 79.6 million people worldwide by 2020. It is caused by the progressive loss of retinal ganglion cells (RGCs), predominantly via apoptosis, within the retinal nerve fibre layer and the corresponding loss of axons of the optic nerve head. One of its most devastating features is its late diagnosis and the resulting irreversible visual loss that is often predictable. Current diagnostic tools require significant RGC or functional visual field loss before the threshold for detection of glaucoma may be reached. To propel the efficacy of therapeutics in glaucoma, an earlier diagnostic tool is required. Recent advances in retinal imaging, including optical coherence tomography, confocal scanning laser ophthalmoscopy, and adaptive optics, have propelled both glaucoma research and clinical diagnostics and therapeutics. However, an ideal imaging technique to diagnose and monitor glaucoma would image RGCs non-invasively with high specificity and sensitivity in vivo. It may confirm the presence of healthy RGCs, such as in transgenic models or retrograde labelling, or detect subtle changes in the number of unhealthy or apoptotic RGCs, such as detection of apoptosing retinal cells (DARC). Although many of these advances have not yet been introduced to the clinical arena, their successes in animal studies are enthralling. This review will illustrate the challenges of imaging RGCs, the main retinal imaging modalities, the in vivo techniques to augment these as specific RGC-imaging tools and their potential for translation to the glaucoma clinic.


Assuntos
Axônios/patologia , Diagnóstico por Imagem/métodos , Técnicas de Diagnóstico Oftalmológico , Glaucoma/diagnóstico , Disco Óptico/patologia , Doenças do Nervo Óptico/diagnóstico , Células Ganglionares da Retina/patologia , Apoptose , Humanos
15.
Cell Death Dis ; 5: e1460, 2014 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-25321467

RESUMO

Cell-based therapies are increasingly recognized as a potential strategy to treat retinal neurodegenerative disease. Their administration, however, is normally indirect and complex, often with an inability to assess in real time their effects on cell death and their migration/integration into the host retina. In the present study, using a partial optic nerve transection (pONT) rat model, we describe a new method of Schwann cell (SC) delivery (direct application to injured optic nerve sheath, SC/DONS), which was compared with intravitreal SC delivery (SC/IVT). Both SC/DONS and SC/IVT were able to be assessed in vivo using imaging to visualize retinal ganglion cell (RGC) apoptosis and SC retinal integration. RGC death in the pONT model was best fitted to the one-phase exponential decay model. Although both SC/DONS and SC/IVT altered the temporal course of RGC degeneration in pONT, SC/DONS resulted in delayed but long-lasting effects on RGC protection, compared with SC/IVT treatment. In addition, their effects on primary and secondary degeneration, and axonal regeneration, were also investigated, by histology, whole retinal counting, and modelling of RGC loss. SC/DONS was found to significantly reduce RGC apoptosis in vivo and significantly increase RGC survival by targeting secondary rather than primary degeneration. Both SC/DONS and SC/IVT were found to promote RGC axonal regrowth after optic nerve injury, with evidence of GAP-43 expression in RGC somas and axons. SC/DONS may have the potential in the treatment of optic neuropathies, such as glaucoma. We show that SC transplantation can be monitored in real time and that the protective effects of SCs are associated with targeting secondary degeneration, with implications for translating cell-based therapies to the clinic.


Assuntos
Nervo Óptico/patologia , Células Ganglionares da Retina/citologia , Células de Schwann/transplante , Algoritmos , Animais , Apoptose , Axônios/metabolismo , Contagem de Células , Movimento Celular , Sobrevivência Celular , Injeções Intravítreas , Masculino , Traumatismos do Nervo Óptico , Ratos , Reprodutibilidade dos Testes , Células de Schwann/citologia
16.
Neurotox Res ; 26(4): 440-6, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25106883

RESUMO

Several lines of evidence suggest that there are similarities in the pathomechanisms of glaucoma and Alzheimer's disease, and that amyloid-beta (Aß) could be a new, promising target for neuroprotective therapy of glaucoma. In the present study, we evaluated the effect of the Aß aggregation modulator MRZ-99030 in the Morrison model of glaucoma based on increased intraocular pressure (IOP) in rats. MRZ-99030 provided dose-dependent neuroprotection and at the highest dose (240 mg/kg) reduced the degree of RGC apoptosis to 33 % of that seen after vehicle (P < 0.05; one-way ANOVA). No significant effect on IOP was observed. Pharmacokinetic experiments showed that following systemic injection of MRZ-99030, concentrations above affinity for Aß were reached. Hence the present results are consistent with the notion that Aß is a promising target for neuroprotective intervention in glaucoma and that MRZ-99030 may be a good drug candidate for further development.


Assuntos
Dipeptídeos/farmacologia , Glaucoma/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Animais , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dipeptídeos/farmacocinética , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Glaucoma/patologia , Glaucoma/fisiopatologia , Pressão Intraocular/efeitos dos fármacos , Masculino , Fármacos Neuroprotetores/farmacocinética , Ratos , Retina/efeitos dos fármacos , Retina/patologia , Retina/fisiopatologia
17.
Arq. bras. med. vet. zootec ; 66(1): 137-144, fev. 2014. ilus, tab
Artigo em Inglês | LILACS | ID: lil-704017

RESUMO

The objective of this study was to assess the reproductive response of adult and prepubertal goats subjected to repeated laparoscopic ovum pick-up (LOPU). The study animals were divided into two groups, specifically, adult nanny goats (GA, n=10) and prepubertal nanny goats (GP, n=10), which were subjected to estrous synchronization and ovarian stimulation for LOPU. Both groups underwent six LOPU procedures at seven-day intervals and were subsequently subjected to controlled mating and pregnancy diagnosis to evaluate their future fertility. The study showed a reduction in the number of follicles visualized and in the amount and quality of the oocytes that were recovered and exposed to in vitro maturation. As indicated by the fertility test, however, no complications were found during the laparoscopic procedures that would impair the reproductive future of the animals. Therefore, a viable number of oocytes were obtained even with the decreased reproductive efficiency, proving that repeated LOPUs do not interfere with the reproductive of adult and prepubertal nanny goats. These results indicate a positive aspect of this procedure, allowing for increasing reproductive performance of this kind, when used for the production in vitro.


O objetivo deste estudo foi avaliar a resposta reprodutiva de cabras adultas e pré-púberes submetidas a repetidas aspirações foliculares por videolaparoscopia (LOPU). Os animais do estudo foram divididos em dois grupos, especificamente cabras adultas (GA, n = 10) e pré-púberes (GP, n = 10), que foram submetidas a sincronização de estro e estimulação ovariana para LOPU. Ambos os grupos foram submetidos a seis procedimentos LOPU em intervalos de sete dias e foram posteriormente submetidos à monta controlada e posterior diagnóstico de gestação para avaliar sua fertilidade. O estudo mostrou uma diminuição do número de folículos visualizados, na quantidade e na qualidade dos oócitos que foram recuperados e expostos à maturação in vitro. Tal como indicado pelo teste de fertilidade, no entanto, não foram observadas grandes complicações durante os procedimentos laparoscópicos que pudessem prejudicar o futuro reprodutivo dos animais. Portanto, foi obtido um número de oócitos viáveis, mesmo com a diminuição da eficiência reprodutiva, provando que repetidas LOPU não interferem na reprodutividade de animais adultos e pré-púberes. Estes resultados indicam um aspecto positivo desse procedimento, possibilitando um aumento da eficiência reprodutiva dessa espécie quando utilizado para a produção in vitro.


Assuntos
Animais , Laparoscopia , Oócitos , Cabras/classificação
18.
Eye (Lond) ; 25(5): 545-53, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21436846

RESUMO

Apoptosis is a form of programmed cell death that is implicated in both pathological and physiological processes throughout the body. Its imaging in vivo with intravenous radiolabelled-annexin V has been heralded as an important advance, with around 30 clinical trials demonstrating its application in the early detection and monitoring of disease, and the assessment of efficacy of potential and existing therapies. A recent development has been the use of fluorescently labeled annexin V to visualize single retinal cells undergoing the process of apoptosis in vivo with ophthalmoscopy. This has been given the acronym DARC (Detection of Apoptosing Retinal Cells). DARC so far has only been used experimentally, but clinical trials are starting shortly in glaucoma patients. Results suggest that DARC may provide a direct assessment of retinal ganglion cell health. By enabling early assessment and quantitative analysis of cellular degeneration in glaucoma, it is hoped that DARC can identify patients before the onset of irreversible vision loss. Furthermore, in addition to aiding the tracking of disease, it may provide a rapid and objective assessment of potential and effective therapies, providing a new and meaningful clinical endpoint in glaucomatous disease that is so badly needed.


Assuntos
Apoptose/fisiologia , Glaucoma/patologia , Retina/citologia , Células Ganglionares da Retina/patologia , Anexina A5 , Glaucoma/fisiopatologia , Humanos , Microscopia de Fluorescência
19.
Neurobiol Dis ; 39(3): 344-51, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20451613

RESUMO

In the age-related, blinding disease glaucoma, retinal ganglion cells (RGCs) degenerate, possibly affecting glutamatergic retinofugal transmission to the brain. The superior colliculus (SC) is a major central target of retinofugal axons in the rodent, a much used disease model. We investigated the contribution of NMDA-type glutamate receptors to retinocollicular transmission in a rat glaucoma model, using a SC brain slice preparation to determine the sensitivity of synaptic responses to the NMDAR antagonist D-AP5. At 32weeks after induction of experimental glaucoma, but not earlier, there was an increase in NMDAR contribution to SC synaptic responses in slices receiving input from glaucomatous eyes. This suggests that there are changes in NMDAR function after RGC degeneration in experimental glaucoma, which may represent functional SC compensation through plasticity via NMDARs. This has implications for studies carried out using rodent glaucoma models, especially those evaluating potential treatment strategies, as it suggests that functional changes in the central visual system need to be considered in addition to those in the eye. Furthermore, the data underline the need for early therapeutic intervention in order to pre-empt subsequent central functional changes.


Assuntos
Glaucoma/fisiopatologia , Receptores de N-Metil-D-Aspartato/metabolismo , Células Ganglionares da Retina/fisiologia , Colículos Superiores/fisiopatologia , Transmissão Sináptica/fisiologia , Vias Visuais/fisiopatologia , Análise de Variância , Animais , Eletrofisiologia , Potenciais Pós-Sinápticos Excitadores/fisiologia , Glaucoma/metabolismo , Masculino , Ratos , Colículos Superiores/metabolismo , Sinapses/metabolismo , Vias Visuais/metabolismo
20.
Curr Alzheimer Res ; 7(1): 3-14, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20205667

RESUMO

Alzheimer's disease (AD) is the major cause of dementia in the world. Although the entorhinal cortex and hippocampal complex are best known as the sites of early pathology in AD, increasing evidence shows that the eye, particularly the retina, is also affected. The AD-related changes in the retina are associated with degeneration and loss of neurons, reduction of the retinal nerve fibres, increase in optic disc cupping, retinal vascular tortusity and thinning, and visual functional impairment. Given the fact that evaluating pathologic changes in the brain during life has always been an indirect process, largely shielded from view by the barrier of the skull, the eye can be used as a window into diseases of the brain. Using modern techniques, the changes in the retina can be visualized in real-time. In addition to the changes in the eyes of AD patients, similar mechanisms of neurodegeneration in the brain have also been demonstrated in the eye. Targeting AD-liked changes in the retina has been recently shown to be effective in the reduction of retinal neuronal degeneration and loss in eye diseases. This review will cover recent findings on retinal degeneration in AD, pathological similarities between AD and eye diseases, and highlight the potential of modern technologies for the detection of prospective biomarkers in the eye in early AD.


Assuntos
Doença de Alzheimer/diagnóstico , Doença de Alzheimer/patologia , Degeneração Retiniana/patologia , Doença de Alzheimer/complicações , Peptídeos beta-Amiloides/metabolismo , Biomarcadores/análise , Diagnóstico Precoce , Humanos , Degeneração Retiniana/etiologia , Proteínas tau/metabolismo
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