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1.
Ophthalmol Retina ; 7(8): 661-671, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37086257

RESUMEN

OBJECTIVE: Determine prevalence, progression rates, and associations of newly detectable macular atrophy (MA) in patients with choroidal neovascularization (CNV) secondary to neovascular age-related macular degeneration (nAMD) with/without ranibizumab treatment. DESIGN: Post hoc analysis of MA in patients with occult/minimally classic nAMD who received monthly intravitreal ranibizumab (0.3 or 0.5 mg) or sham injections for 24 months (M) in MARINA, a phase III trial in treatment-naive patients (NCT00056836). PARTICIPANTS: Seven hundred six patients with nAMD: ranibizumab 0.3 mg, n = 236; 0.5 mg, n = 237; sham, n = 233. METHODS: Macular atrophy, assessed by color fundus photographs/fluorescein angiography, was classified as "within," "adjacent," or "nonadjacent" to the original CNV lesion. Factors associated with MA were assessed by multivariate logistic regression. MAIN OUTCOME MEASURES: Prevalence/incidence of newly detectable MA over time, association with CNV area, MA progression rate, association of MA with visual acuity (VA), changes in CNV/leakage area, and factors predictive of new MA at 24M. RESULTS: At 24M, new MA was detected in 36.8%, 40.4%, and 21.0% of eyes for ranibizumab 0.3 mg, 0.5 mg, and sham, respectively, most frequently within the area of the baseline CNV lesion (93.2%, 85.0%, and 69.0%). Rate of MA progression was similar across arms (∼ 0.3 to 0.4 mm/year). There was strong association between absence of fibrosis and detectable MA (odds ratio, 2.7; 95% confidence interval [CI], 1.29-5.56), whereas an association was not identified between detectable MA and baseline VA, baseline fellow eye atrophy, ranibizumab treatment, or change in leakage/CNV area at 24M. Ranibizumab-treated eyes gained VA with (0.3 mg: 5.3 letters [95% CI, -3.3, 13.8]; 0.5 mg: 9.8 [4.7-15.0]) or without new MA (0.3 mg: 6.4 [4.1-8.6]; 0.5 mg: 8.0 [5.3-10.6]), whereas VA in sham-treated eyes deteriorated with/without new MA (-14.7 [-23.6, -5.8] and -14.0 [-16.9, -11.1], respectively). CONCLUSIONS: New MA was more frequently detected in ranibizumab-treated than sham-treated eyes. Macular atrophy progression was similar across arms. Multivariate analysis showed that absence of fibrosis was the only variable associated with increased MA. Regardless of MA presence/location at baseline or throughout the study, ranibizumab-treated eyes showed clinically significant improvements in VA, whereas VA in sham-treated eyes worsened. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.


Asunto(s)
Neovascularización Coroidal , Degeneración Macular , Humanos , Ranibizumab/uso terapéutico , Inhibidores de la Angiogénesis/uso terapéutico , Prevalencia , Inyecciones Intravítreas , Degeneración Macular/complicaciones , Neovascularización Coroidal/diagnóstico , Neovascularización Coroidal/tratamiento farmacológico , Neovascularización Coroidal/epidemiología , Atrofia/tratamiento farmacológico , Fibrosis
2.
JAMA Ophthalmol ; 138(9): 964-972, 2020 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-32729897

RESUMEN

Importance: Faricimab neutralizes angiopoietin-2 and vascular endothelial growth factor A via both simultaneous and independent binding. Objective: To evaluate extended dosing with faricimab, the first bispecific antibody designed for intraocular use, in patients with neovascular age-related macular degeneration. Design, Setting, and Participants: This phase 2 randomized clinical trial was a 52-week multicenter, active comparator-controlled, parallel-group study. Study participants were enrolled in 25 sites in the US from January and March 2017 with treatment-naive choroidal neovascularization secondary to neovascular age-related macular degeneration and best-corrected visual acuity (BCVA) Early Treatment Diabetic Retinopathy Study letter score of 73 (approximate Snellen equivalent, 20/40) to 24 (approximate Snellen equivalent, 20/320). Analysis began January 2017 and ended March 2018. Interventions: Participants were randomized 1:2:2 to receive intravitreal ranibizumab, 0.5 mg, every 4 weeks or faricimab, 6.0 mg, every 12 or 16 weeks. Participants in the faricimab arms initially received 4 monthly injections of faricimab. No rescue injections were allowed. Participants randomized to dosing every 16 weeks were assessed for disease activity at week 24 using prespecified criteria. Those with no active disease continued dosing every 16 weeks through trial end; participants with disease activity continued received dosing every 12 weeks. Main Outcomes and Measures: Mean change in BCVA from baseline at week 40. Results: Of 76 participants enrolled (mean [SD] age, 78.5 [8.5] years; age range, 56-94 years; 41 women [58%]; 69 white [97%]), 16 (21.0%) were randomized to ranibizumab every 4 weeks, 29 (38.2%) to faricimab every 12 weeks, and 31 (40.8%) to faricimab every 16 weeks. At week 24, 12 weeks after their last initiation injection, 65% (36 of 55) of all faricimab-treated participants had no disease activity. At week 40, adjusted mean BCVA gains from baseline (Early Treatment Diabetic Retinopathy Study letters) were +11.4 (80% CI, 7.8-15.0), +9.3 (80% CI, 6.4-12.3), and +12.5 (80% CI, 9.9-15.1) for the ranibizumab every 4 weeks, faricimab every 12 weeks, and faricimab every 16 weeks arms, respectively. Participants received a mean (SD) total of 12.9 (0.25), 6.7 (0.91), and 6.2 (0.93) injections, for the ranibizumab every 4 weeks, faricimab every 12 weeks, and faricimab every 16 weeks arms, respectively, through week 52. The secondary BCVA and anatomical imaging end points supported the primary end point and were comparable with ranibizumab every 4 weeks. No new or unexpected safety signals were identified. Conclusions and Relevance: At week 52, faricimab dosing every 16 weeks and every 12 weeks resulted in maintenance of initial vision and anatomic improvements comparable with monthly ranibizumab. These results suggest a role for simultaneous neutralization of angiopoietin-2 and vascular endothelial growth factor A in providing sustained efficacy through extended durability, warranting further investigation. Trial Registration: ClinicalTrials.gov Identifier: NCT03038880.


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Ranibizumab/administración & dosificación , Degeneración Macular Húmeda/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Inhibidores de la Angiogénesis/administración & dosificación , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Estudios de Seguimiento , Humanos , Inyecciones Intravítreas , Masculino , Persona de Mediana Edad , Factores de Tiempo , Resultado del Tratamiento , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Degeneración Macular Húmeda/diagnóstico
3.
Ophthalmol Retina ; 2(7): 667-675, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-31047375

RESUMEN

OBJECTIVE: Ranibizumab safety is well established for treatment of neovascular age-related macular degeneration (nAMD), but less is known about the risk of systemic serious adverse events (SAEs), specifically among patients with heightened baseline risk due to age (≥85 years). This analysis examines whether patients ≥85 years of age versus those <85 years experience an increased risk of key systemic SAEs during intravitreal ranibizumab treatment for nAMD. DESIGN: Retrospective, pooled analysis of safety data from 5 phase III/IIIb multicenter randomized clinical trials in patients with nAMD: ANCHOR, MARINA, PIER, SAILOR, and HARBOR. PARTICIPANTS: Patients with nAMD receiving ranibizumab (n = 4347) or control (sham/verteporfin photodynamic therapy, n = 441) treatment included in the safety-evaluable set of the 5 trials. METHODS: The incidence of nonocular SAEs was analyzed stratified by age (<85 years [n = 3795] vs ≥85 years [n = 993]), treatment (control, ranibizumab 0.3 mg, ranibizumab 0.5 mg, ranibizumab 2.0 mg), and injection frequency (monthly, as needed [PRN]). MAIN OUTCOME MEASURES: Incidence of key systemic SAEs, defined as total nonocular SAEs, deaths, cardiovascular events, cerebrovascular (CBV) events, and Antiplatelet Trialists' Collaboration events. RESULTS: The MARINA and ANCHOR trials had greater rates of key SAEs for patients ≥85 years versus those <85 years. Ranibizumab exposure did not increase the risk of most SAEs in elderly patients; for CBV events and death, the effect of ranibizumab versus control treatment for age ≥85 years was not interpretable due to small number of events (CBV: n = 2, 2, 5 for control, ranibizumab 0.3 mg, and ranibizumab 0.5 mg, respectively; death: n = 2, 4, 5, respectively). Across all 5 trials, an increased risk was found for age ≥85 years versus <85 years for the marketed dose of ranibizumab 0.5 mg. In the HARBOR trial, increased rates of key SAEs (excluding total nonocular SAEs) for age ≥85 years versus <85 years were observed with monthly dosing but not with PRN dosing; event rates were similar for 2.0 mg versus 0.5 mg. CONCLUSIONS: Consistent with general trends, the risk of key systemic SAEs was associated with age ≥85 years versus <85 years, but not with ranibizumab drug exposure. The difference between monthly versus PRN was inconclusive. There was no evidence of a dose effect. Interpretation of this retrospective analysis is limited because it was not prospectively powered for statistically definitive conclusions.

4.
Ophthalmol Retina ; 2(11): 1087-1096, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-31047547

RESUMEN

TOPIC: This study evaluated the cardiovascular/cerebrovascular safety profile of ranibizumab 0.5 mg versus sham ± verteporfin in patients with neovascular age-related macular degeneration (nAMD). In addition, comparisons of ranibizumab 0.3 mg with sham and ranibizumab 0.5 mg to 0.3 mg were performed. CLINICAL RELEVANCE: Intravitreal anti-vascular endothelial growth factor (VEGF) agents carry potential increased systemic risks, including cardiovascular or cerebrovascular events. Pooled safety analyses allow better interpretation of safety outcomes seen in individual clinical trials, especially for less common events. To our knowledge, this is the largest patient-level pooled analysis of patients with nAMD treated with ranibizumab. METHODS: Patient-level pooled analysis of data from 7 Genentech- and Novartis-sponsored phase II, III, and IV studies in nAMD that were completed by December 31, 2013. Pairwise comparisons (primary comparison: ranibizumab 0.5 mg [globally approved dose for nAMD] vs. sham or verteporfin) were performed using Cox proportional hazard regression (hazard ratios [HRs], 95% confidence intervals [CIs]) and rates per 100 patient-years. Standardized Medical Dictionary for Regulatory Activities queries (SMQs) and extended searches were used to identify relevant safety endpoints, including arterial thromboembolic events (ATEs), myocardial infarction (MI), stroke or transient ischemic attack (TIA), stroke (excluding TIA), vascular deaths, and major vascular events as defined by the Antiplatelet Trialists' Collaboration (APTC). RESULTS: The HRs (95% CIs) for the primary comparison of ranibizumab 0.5 mg (n=480) versus sham or verteporfin (n=462) were 1.16 (0.72-1.88) for ATE, 1.33 (0.59-2.97) for MI, 1.43 (0.54-3.77) for stroke excluding TIA, 1.25 (0.61-2.55) for stroke or TIA, 0.57 (0.18-1.78) for vascular death, and 1.12 (0.64-1.98) for APTC events. Hazard ratio 95% CIs included 1, indicating no significant treatment differences, for all endpoints for comparison of ranibizumab 0.5 mg versus sham or verteporfin. CONCLUSIONS: The rates of cardiovascular and cerebrovascular events were low in these patients with nAMD and not clinically meaningfully different for patients treated with ranibizumab 0.5 mg versus sham or verteporfin, which supports the favorable benefit-risk profile of ranibizumab in the patient population with nAMD. Pooling these studies allows an analysis with higher power and precision compared with individual study analyses.

5.
Ann Rheum Dis ; 71(8): 1289-96, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22307942

RESUMEN

OBJECTIVE: To determine the efficacy and safety of ocrelizumab (OCR) with methotrexate (MTX) in MTX-naive rheumatoid arthritis (RA) patients. METHODS: In a randomised, double-blind, controlled trial, patients received placebo+MTX (MTX; n=210), OCR 200 mg×2+MTX (OCR 200; n=200) or OCR 500 mg×2+MTX (OCR 500; n=203). OCR/placebo (two intravenous infusions) was given on days 1 and 15, with fixed re-treatment scheduled at weeks 24/26, 52/54 and 76/78. Due to early termination of OCR dosing, there was no formal primary end point analysis (change from baseline in modified total Sharp score (ΔmTSS) at week 104). Analyses are reported for week 52 outcomes. RESULTS: At week 52, treatment with OCR+MTX compared with MTX alone reduced progression of joint damage (mean (SD) change in ΔmTSS: OCR 200, 0.66 (4.51); OCR 500, 0.27 (2.91); MTX alone, 1.59 (4.82); p=0.001 and p=0.003, respectively vs MTX alone) and improved clinical signs and symptoms (American College of Rheumatology 20 response: OCR 200, 73.0%; OCR 500, 71.0%; MTX alone, 57.5%; p<0.005 for each OCR vs MTX alone). Serious infection rates per 100 patient-years were similar with OCR 200 and MTX alone (2.6 (95% CI 0.9 to 6.1) and 3.0 (1.1 to 6.5), respectively), but higher with OCR 500 (7.1 (3.9 to 11.9)). CONCLUSIONS: OCR 200 mg and 500 mg with MTX in MTX-naive patients with RA were effective in inhibiting joint damage progression and improving RA signs and symptoms. OCR 500 mg with MTX was associated with an increased rate of serious infections.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Metotrexato/uso terapéutico , Anticuerpos Monoclonales Humanizados/efectos adversos , Antirreumáticos/efectos adversos , Artritis Reumatoide/patología , Artritis Reumatoide/fisiopatología , Progresión de la Enfermedad , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Quimioterapia Combinada , Femenino , Humanos , Huésped Inmunocomprometido , Infecciones/epidemiología , Infecciones/etiología , Infecciones/inmunología , Infusiones Intravenosas , Articulaciones/efectos de los fármacos , Articulaciones/patología , Articulaciones/fisiopatología , Masculino , Metotrexato/efectos adversos , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
6.
Neurogenetics ; 12(1): 19-24, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21174137

RESUMEN

Small molecules that increase full-length survivor motor neuron (SMN) gene transcript are promising therapeutic candidates for spinal muscular atrophy (SMA). Hydroxyurea (HU) has recently been shown to increase full-length SMN transcript in cultured lymphocytes from patients with SMA. We investigate the mechanism by which HU enhances full-length SMN2 gene expression in SMA lymphocytes. Nitric oxide (NO) is a major intracellular metabolite of HU. We test whether NO donors can themselves enhance full-length SMN2 expression. Eighteen cell lines (five type I, five type II, six type III SMA, and two non-SMA controls) were treated with or without NO donors for 48 h. SMA cells treated with HU and three NO donors: two long-acting donors, Deta-NONOate and S-nitrosoglutathione, and one short-acting donor, 3-ethyl-3-(ethylaminoethyl)-1-hydroxy-2-oxo-1-triazene, resulted in significant increase in full-length SMN2 mRNA. These effects were abolished by co-treatment with an NO scavenger 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide. One short-acting NO donor, S-nitroso-N-acetyl-DL-penicillamine, failed to show significant effect on full-length SMN2 expression, possibly due to high degree of cytotoxicity. These results were observed using both densitometry and quantitative PCR methods. We conclude that HU enhances SMN2 expression through the release of NO. NO donors may themselves be considered as new therapeutic candidates for SMA.


Asunto(s)
Hidroxiurea/farmacología , Atrofia Muscular Espinal/tratamiento farmacológico , Atrofia Muscular Espinal/genética , Óxido Nítrico/metabolismo , Secuencia de Bases , Línea Celular , Óxidos N-Cíclicos/farmacología , Cartilla de ADN/genética , Depuradores de Radicales Libres/farmacología , Expresión Génica/efectos de los fármacos , Humanos , Imidazoles/farmacología , Linfocitos/efectos de los fármacos , Linfocitos/metabolismo , Atrofia Muscular Espinal/metabolismo , Donantes de Óxido Nítrico/farmacología , Compuestos Nitrosos/farmacología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteína 2 para la Supervivencia de la Neurona Motora/genética
7.
Sleep Breath ; 15(1): 13-20, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20082240

RESUMEN

PURPOSE: Sodium oxybate (SXB) is approved for cataplexy and excessive daytime sleepiness in narcolepsy. Obstructive sleep apnea syndrome (OSAS) affects ∼9-50% of narcoleptics. Effects of 2-week SXB administration on apnea-hypopnea index (AHI), oxygen saturation (SaO(2)), and sleep architecture were investigated in OSAS patients. METHODS: OSAS patients (n = 48) received 2-week SXB or placebo (PBO) treatment with polysomnography at baseline and day 14. The primary outcome measure was change from baseline in mean AHI. Secondary outcomes included changes from baseline in SaO(2), and sleep architecture. RESULTS: Compared with PBO, SXB significantly increased reduction in mean AHI and obstructive apnea index with SXB (-0.8 ± 13.3 vs. -8.2 ± 10.0; p = 0.0327 and 3.54 ± 11.1 vs. -4.72 ± 7.7; p = 0.0054, respectively) and significantly increased change in slow wave sleep duration (5.2 ± 25.0 min vs. 29.4 ± 37.0 min; p = 0.0038). There were no differences between treatments in SaO2, central apneic events, or other measures. Adverse events, most commonly headache, were noted in nine of 27 (33%) and six of 23 (26%) patients receiving SXB and PBO, respectively. CONCLUSIONS: Short-term use of 4.5 g/night SXB did not generate respiratory depressant effects in OSAS patients as measured by AHI, obstructive apnea events, central apneas, and SaO2. Extended use of SXB in higher therapeutic doses in OSAS has not been studied, and merits caution.


Asunto(s)
Adyuvantes Anestésicos/uso terapéutico , Polisomnografía/efectos de los fármacos , Apnea Obstructiva del Sueño/tratamiento farmacológico , Oxibato de Sodio/uso terapéutico , Adyuvantes Anestésicos/efectos adversos , Adulto , Compuestos de Bencidrilo/efectos adversos , Compuestos de Bencidrilo/uso terapéutico , Estimulantes del Sistema Nervioso Central/efectos adversos , Estimulantes del Sistema Nervioso Central/uso terapéutico , Terapia Combinada , Presión de las Vías Aéreas Positiva Contínua , Trastornos de Somnolencia Excesiva/tratamiento farmacológico , Quimioterapia Combinada , Femenino , Humanos , Hipnóticos y Sedantes/efectos adversos , Hipnóticos y Sedantes/uso terapéutico , Masculino , Persona de Mediana Edad , Modafinilo , Piridinas/efectos adversos , Piridinas/uso terapéutico , Oxibato de Sodio/efectos adversos , Zolpidem
8.
Sleep Med ; 11(1): 38-42, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19897413

RESUMEN

OBJECTIVE: Sodium oxybate (SXB) is an approved drug for the treatment of excessive daytime sleepiness (EDS) and cataplexy in narcolepsy. Obstructive sleep apnea syndrome (OSAS) is a condition that frequently co-occurs with narcolepsy. Given the known central nervous system (CNS) depressant effects of SXB, this study aimed to examine its effects on sleep-disordered breathing (SDB) and sleep architecture in patients with OSAS. METHODS: Sixty patients with a history of mild to moderate OSAS (apnea-hypopnea index [AHI]>or=10 and or=75%) received one of four treatments of the following: (1) 9g SXB, (2) 9g SXB/modafinil 200mg, (3) zolpidem 10mg, and (4) placebo (PBO) in a randomized, crossover design on four consecutive nights followed by overnight polysomnography. RESULTS: Forty-two patients (70%) completed the study. The mean change from baseline in AHI and mean SaO(2) was not significantly different among groups following treatment. Central apneas in patients treated with SXB increased, and clinically significant oxygen desaturations were seen in three patients with SXB treatment. The most common treatment related adverse events were headache and nausea. CONCLUSION: These results suggest that nighttime administration of 9g SXB in patients with mild to moderate OSAS does not negatively impact SDB, as measured by mean change from baseline in AHI and SaO(2), but might increase central apneas and cause oxygen desaturation in some individuals and should be used with caution.


Asunto(s)
Adyuvantes Anestésicos/efectos adversos , Compuestos de Bencidrilo/efectos adversos , Estimulantes del Sistema Nervioso Central/efectos adversos , Hipnóticos y Sedantes/efectos adversos , Polisomnografía/efectos de los fármacos , Piridinas/efectos adversos , Apnea Obstructiva del Sueño/tratamiento farmacológico , Oxibato de Sodio/efectos adversos , Adyuvantes Anestésicos/uso terapéutico , Adulto , Anciano , Compuestos de Bencidrilo/uso terapéutico , Estimulantes del Sistema Nervioso Central/uso terapéutico , Comorbilidad , Presión de las Vías Aéreas Positiva Contínua , Estudios Cruzados , Método Doble Ciego , Quimioterapia Combinada , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Femenino , Humanos , Hipnóticos y Sedantes/uso terapéutico , Masculino , Persona de Mediana Edad , Modafinilo , Narcolepsia/tratamiento farmacológico , Narcolepsia/epidemiología , Oxígeno/sangre , Vigilancia de Productos Comercializados , Piridinas/uso terapéutico , Apnea Obstructiva del Sueño/epidemiología , Fases del Sueño/efectos de los fármacos , Oxibato de Sodio/uso terapéutico , Zolpidem
9.
Ann Neurol ; 58(2): 194-202, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16049920

RESUMEN

Spinal muscular atrophy (SMA) is a motor neuron disease caused by dysfunction of the survival motor neuron (SMN) gene. Human SMN gene is present in duplicated copies: SMN1 and SMN2. More than 95% of patients with SMA lack a functional SMN1 but retain at least one copy of SMN2. Unlike SMN1, SMN2 is primarily transcribed into truncated messenger RNA and produces low levels of SMN protein. We tested a therapeutic strategy by treating cultured lymphocytes from patients with SMA with hydroxyurea to modify SMN2 gene expression and to increase the production of SMN protein. Twenty lymphoblastoid cell lines (15 SMA and 5 control lines) were treated with hydroxyurea at 5 concentrations (0.5, 5, 50, 500, and 5,000 microg/ml) and 3 time points (24, 48, and 72 hours). SMN2 gene copy numbers were determined using real-time quantitative polymerase chain reaction. Hydroxyurea treatment resulted in a time-related and dose-dependent increase in the ratio of full-length to truncated SMN messenger RNA. SMN protein levels and intranuclear gems also were significantly increased in these hydroxyurea-treated cells. The SMN2 gene copy number correlated inversely with the SMA phenotypic severity. This study provides the first evidence for a therapeutic indication of hydroxyurea in SMA.


Asunto(s)
Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Inhibidores Enzimáticos/farmacología , Expresión Génica/efectos de los fármacos , Hidroxiurea/farmacología , Linfocitos/efectos de los fármacos , Atrofia Muscular Espinal/genética , Proteínas del Tejido Nervioso/metabolismo , Proteínas de Unión al ARN/metabolismo , Western Blotting , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/genética , Relación Dosis-Respuesta a Droga , Dosificación de Gen , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Inmunohistoquímica/métodos , Linfocitos/metabolismo , Neuronas Motoras/efectos de los fármacos , Neuronas Motoras/metabolismo , Atrofia Muscular Espinal/clasificación , Atrofia Muscular Espinal/patología , Proteínas del Tejido Nervioso/genética , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Proteínas del Complejo SMN , Proteína 1 para la Supervivencia de la Neurona Motora , Proteína 2 para la Supervivencia de la Neurona Motora , Factores de Tiempo
10.
Neurochem Int ; 46(2): 127-35, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15627513

RESUMEN

There is increasing evidence showing the involvement of unsaturated free fatty acids in cell death pathways, particularly in the context of apoptotic signalling. Our previous in vitro study has demonstrated that oleic acid, a monounsaturated fatty acid, reduces phosphorylation of proapoptotic Bad through activation of protein phosphatase type 2Cbeta. In the present study, we attempted to investigate the role of oleic acid in neuronal apoptosis using different types of cell cultures, and, furthermore, to explore the underlying mechanism with regard to its effect on Bad expression. As revealed by nuclear staining, oleic acid caused a concentration- and time-dependent damage with typical apoptotic features in cortical and hippocampal cultures from embryonic and neonatal rats, respectively, as well as in human neuroblastoma SH-SY5Y cells. In mixed hippocampal cultures, nearly all neurons were damaged at 24 h after the treatment, while damage of astrocytes was detected 48 h after adding this fatty acid, suggesting that neurons were more vulnerable than astrocytes. Nile blue staining showed that oleic acid and oleic acid methyl ester were both taken up by the neurons within 30 min. In contrast to oleic acid, oleic acid methyl ester did not change cell viability demonstrating that oleic acid-induced cell death was not due to an overload of the cells with lipids. Caspase-3 activity was not increased by oleic acid in cultured hippocampal cells. Western blot analysis of phospho-Ser112 Bad and the total Bad in cultured hippocampal cells revealed a significant decrease in the ratio of phospho-Ser112 Bad to total Bad in a time- and concentration-dependent manner after the exposure with oleic acid. We conclude that oleic acid induces neuronal apoptosis through a caspase-3-independent mechanism involving dephosphorylation of Bad.


Asunto(s)
Apoptosis/efectos de los fármacos , Proteínas Portadoras/metabolismo , Ácido Oléico/farmacología , Animales , Astrocitos/efectos de los fármacos , Bisbenzimidazol , Western Blotting , Caspasa 3 , Caspasas/metabolismo , Células Cultivadas , Colorantes Fluorescentes , Hipocampo/citología , Hipocampo/efectos de los fármacos , Humanos , Neuronas/efectos de los fármacos , Ácido Oléico/metabolismo , Oxazinas , Fosforilación/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Proteína Letal Asociada a bcl
11.
J Neurosci ; 23(25): 8733-42, 2003 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-14507973

RESUMEN

Blood-brain barrier (BBB) dysfunction is a potential mechanism involved in progressive striatal damage induced by the mitochondrial excitotoxin, 3-nitropropionic acid (3-NP). After activation by proteases and free radicals, matrix metalloproteinases (MMPs), particularly MMP-9 and -2, can digest the endothelial basal lamina leading to BBB opening. Using CD-1 mice, we show that MMP-9 expression by zymography is increased in the injured striatum compared with the contralateral striatum 2 hr after 3-NP injection [133.50 +/- 57.17 vs 50.25 +/- 13.56; mean +/- SD of optical densities in arbitrary units (A.U.); p < 0.005] and remains elevated until 24 hr (179.33 +/- 78.24 A.U.). After 4 hr, MMP-9 expression and activation are accompanied by an increase in BBB permeability. MMP inhibition attenuates BBB disruption, swelling, and lesion volume compared with vehicle-treated controls. There is a clear spatial relationship between MMP-9 expression and oxidized hydroethidine, indicating reactive oxygen species (ROS) production. Furthermore, transgenic mice that overexpress copper/zinc-superoxide dismutase (SOD1) show decreased lesion size and edema along with decreased immunoreactivity for MMP-9, compared with wild-type littermates (lesion: 38.8 +/- 15.1 and 53.3 +/- 10.3, respectively, p < or = 0.05; edema: 21.8 +/- 11.2 and 35.28 +/- 11, respectively, p < or = 0.05; MMP-9-positive cells: 352 +/- 57 and 510 +/- 45, respectively, p < or = 0.005), whereas knock-out mice deficient in SOD1 display significantly greater swelling (48.65 +/- 17; p < or = 0.05). We conclude that early expression and activation of MMP-9 by ROS may be involved in early BBB disruption and progressive striatal damage after 3-NP treatment.


Asunto(s)
Barrera Hematoencefálica , Cuerpo Estriado/efectos de los fármacos , Guanosina/análogos & derivados , Metaloproteinasa 9 de la Matriz/metabolismo , Enfermedades Neurodegenerativas/inducido químicamente , Propionatos , Animales , Conducta Animal/efectos de los fármacos , Barrera Hematoencefálica/efectos de los fármacos , Edema Encefálico/inducido químicamente , Edema Encefálico/prevención & control , Cuerpo Estriado/patología , Cuerpo Estriado/fisiopatología , Guanosina/análisis , Guanosina/biosíntesis , Inmunohistoquímica , Masculino , Metaloproteinasa 2 de la Matriz/metabolismo , Ratones , Ratones Noqueados , Mitocondrias/efectos de los fármacos , Actividad Motora/efectos de los fármacos , Enfermedades Neurodegenerativas/patología , Enfermedades Neurodegenerativas/fisiopatología , Nitrocompuestos , Estrés Oxidativo/efectos de los fármacos , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo , Superóxido Dismutasa/farmacología , Superóxido Dismutasa-1
12.
J Neurotrauma ; 20(6): 571-81, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12906741

RESUMEN

Manganese superoxide dismutase (Mn-SOD, SOD2) is an inducible antioxidant localized to the mitochondria, which have been shown to be both the sites of superoxide anion (O(2)*-)) production and the target of free radical attacks. Knock-out mice with targeted disruption of Sod2 (SOD2-KO) are more susceptible to ischemic damage than their wild-type (WT) counterparts, showing increased loss of mitochondrial cytochrome c after trauma, but less apoptotic cell death in the first 24 h following controlled cortical injury. In this study, we sought to investigate whether oxidative stress plays a significant role in the development of secondary brain damage following cold injury-induced brain trauma (CIBT), a model of vasogenic edema. We first measured the levels of O(2)(*-) production 2 h after CIBT by means of in situ hydroethidine oxidation. We then examined lesion size, brain swelling, apoptosis by morphology and TUNEL-staining, neutrophil infiltration, and hemorrhage rates in both SOD2-KO and WT mice at 1, 3, and 7 days post-CIBT. We found no significant differences between SOD2-KO and WT littermates in any of the paradigms or endpoints studied. There was, however, a significant increase in hemorrhagic transformations in all animals that paralleled a robust inflammatory response at 3 days post insult compared with the 24-h endpoint. In the CIBT model used in this study, a 50% reduction in SOD2 activity did not appear to alter the injury response, suggesting that accumulation of free radicals does not play a significant role in secondary brain damage as previously thought with this particular model.


Asunto(s)
Lesiones Encefálicas/enzimología , Frío/efectos adversos , Superóxido Dismutasa/deficiencia , Animales , Lesiones Encefálicas/genética , Lesiones Encefálicas/patología , Masculino , Ratones , Ratones Noqueados , Estrés Oxidativo/fisiología , Superóxido Dismutasa/genética
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