Treatment of refractory amblyopia with levodopa associated with full-time occlusion in the dominant eye / Tratamento da ambliopia refratária com o uso de levodopa associada à oclusão total do olho dominante

Abstract Purpose: To evaluate visual outcomes of levodopa treatment associated with full occlusion of the dominant eye in patients with refractory amblyopia. Methods: A prospective study of 19 attended patients who were subject to treatment with Levodopa and Carbidopa on doses of 0.7mg/kg/day, a ratio of 4:1 divided into three daily doses for 5 weeks, combined with full occlusion (24 hours/day) of the dominant eye. The ophthalmologic exam from previous consultations up to treatment and after 8 weeks of therapy were collected from medical record data. Patients who had completed treatment for more than 12 months were included for complete eye examination. Results: The mean age before treatment with levodopa was 11.0 ± 4.2 years old (varying from 7 to 23 years). The best-corrected visual acuity (Snellen chart) of the amblyopic eye before treatment was 0.24 (0.6 in logMAR) ± 0.16, after 8 weeks of treatment it was 0.47(0.3 in logMAR) ± 0.33, while during the final evaluation it was 0.46 (0.3 in logMAR) ± 0.34. There was a statistically significant improvement in vision after 8 weeks of therapy which was maintained until the final evaluation (p = 0.007). Conclusion: Levodopa/Carbidopa therapyat doses of 0.7 mg/kg/day at a ratio of 4:1 divided in three daily doses, associated with full occlusion of the dominant eye during 5 weeks had a significant improvement on the visual acuity of the amblyopic eye, and persisted up to 1 year after the treatment.

Resumo Objetivo: Avaliar os resultados visuais do tratamento com levodopa associada à oclusão total do olho dominante em pacientes amblíopes. Métodos: Estudo prospectivo de 19 pacientes atendidos e submetidos ao tratamento com levodopa e carbidopa na dose de 0,7 mg/kg/dia e proporção de 4:1, divididos em três doses diárias, durante cinco semanas, combinada a oclusão total (24 horas/dia) do olho dominante. Foram coletados dados do prontuário referentes ao exame oftalmológico da consulta anterior ao tratamento e após 8 semanas de terapia. Os pacientes com término do tratamento com mais de 12 meses foram reconvocados para exame oftalmológico completo. Resultados: A média de idade dos pacientes previamente ao tratamento com levodopa foi de 11,0 ± 4,2 anos (variando de 7 a 23 anos). A acuidade visual melhor corrigida (Snellen) do olho amblíope antes do tratamento foi de 0,24 (0,6 em logMAR) ± 0,16, após 8 semanas de tratamento foi de 0,47 (0,3 em logMAR) ± 0,33 e na avaliação final foi de 0,46 (0,3 em logMAR) ± 0,34. Houve melhora estatisticamente significante da visão após 8 semanas de tratamento que se manteve até a avaliação final (p = 0,007) Conclusão: A terapia com levodopa/carbidopa em doses de 0,7mg/kg/dia na proporção de 4:1 dividida em três doses diárias, associada à oclusão total do olho dominante durante 5 semanas, apresentou uma melhora significativa na acuidade visual do olho ambliópico e persistiu até 1 ano após o tratamento.

Coumarin analogue 3-methyl-7H-furo[3,2-g]chromen-7-one as a possible antiparkinsonian agent / El análogo de cumarina 3-metil-7H-furo[3,2-g]cromen-7-ona, un posible agente antiparkinsoniano

Abstract Introduction: Parkinson's disease is the second most common neurodegenerative disease. Monoamine oxidase B inhibitors are used in the treatment of this disease concomitantly with levodopa or as monotherapy. Several substituted coumarins have shown activity as inhibitors of monoamine oxidase B. Objective: To evaluate the possible antiparkinsonian effects of the coumarin analogue FCS005 (3-methyl-7H-furo[3,2-g]chromen-7-one) in mouse models, as well as its inhibitory activity towards monoamine oxidases (MAO) and its antioxidant activity. Materials and methods: FCS005 was synthesized and the reversal of hypokinesia was evaluated in the reserpine and levodopa models. Moreover, in the haloperidol model, its anticataleptic effects were evaluated. Additionally, the monoamine oxidase inhibitory activity and antioxidant activity of FCS005 were evaluated using in vitro and ex vivo studies, respectively. Results: FCS005 (100 mg/kg) caused the reversal of hypokinesia in the reserpine and levodopa models. This furocoumarin also presented anti-cataleptic effects at the same dose. Besides, it showed selective inhibitory activity towards the MAO-B isoform and antioxidant activity. Conclusion: These results attribute interesting properties to the compound FCS005. It is important to continue research on this molecule considering that it could be a potential antiparkinsonian agent.

Resumen Introducción. El segundo trastorno neurodegenerativo más común es la enfermedad de Parkinson. Los inhibidores de la monoamino oxidasa B se emplean en el tratamiento de esta enfermedad en monoterapia o concomitantemente con levodopa. Varios compuestos cumarínicos han mostrado actividad como inhibidores de la monoamino oxidasa B. Objetivo. Evaluar los posibles efectos antiparkinsonianos del análogo de la cumarina FCS005 (3-methyl-7H-furo [3,2-g ] chromen-7-one) en modelos de ratones, la actividad inhibitoria frente a las monoamino oxidasas (MAO) y la actividad antioxidante. Materiales y métodos. Se sintetizó la furanocumarina FCS005 y, en los modelos de reserpina y levodopa, se evaluó si producía reversión de la hipocinesia; en el modelo de haloperidol se evaluaron sus efectos anticatalépticos. Además, se evaluó in vitro la actividad inhibidora de MAO y, ex vivo, la actividad antioxidante del compuesto FCS005. Resultados. El compuesto FCS005 en dosis de 100 mg/kg produjo la remisión de la hipocinesia en los modelos de reserpina y de levodopa. Esta furanocumarina presentó efectos anticatalépticos con la misma dosis. Además, mostró tener actividad inhibitoria selectiva sobre la MAO B, así como efectos antioxidantes. Conclusión. Los resultados evidenciaron propiedades interesantes del compuesto FCS005. Es importante continuar investigando esta molécula porque puede ser un potencial agente antiparkinsoniano.

Actualización en enfermedad con cuerpos de Lewy / Update in Lewy body disease

La enfermedad con cuerpos de Lewy incluye 2 entidades que podrían ser consideradas variantes clínicas de una misma patología: la demencia con cuerpos de Lewy y la demencia en enfermedad de Parkinson. Con la finalidad de describir correctamente lo que sucede en la evolución de la enfermedad se divide el cuadro en etapa prodrómica y de demencia propiamente dicha. La primera está clínicamente representada por aquel período en el cual, si bien el paciente exhibe algunos signos y síntomas propios de la enfermedad, no reúne criterios de demencia. A pesar de ser difícil de definir y por carecerse todavía de contundentes datos clínicos y biomarcadores, se caracteriza principalmente por deterioro leve selectivo en función atencional ­ visuoespacial, trastorno del sueño REM y disautonomía‒. La segunda etapa está claramente caracterizada en los criterios de consenso del año 2005. Recientemente hemos publicado la validación de un instrumento llamado ALBA Screening Instrument, que permite diagnosticar con alta sensibilidad y especificidad la enfermedad aun en etapas tempranas y diferenciarla de otras patologías semejantes. La tomografía por emisión de positrones (PET) para transportador de dopamina es el procedimiento de referencia (gold standard) del diagnóstico. El tratamiento sintomático con anticolinesterásicos y neurolépticos atípicos favorece una buena evolución de la enfermedad y es fundamental tener en cuenta evitar medicamentos que pueden dañar gravemente a los pacientes como los anticolinérgicos y antipsicóticos típicos. Los avances en el diagnóstico y la difusión del impacto de esta enfermedad en la población contribuirán a generar mayores esfuerzos de investigación para hallar un tratamiento eficaz, preventivo o curativo o de ambas características. (AU)

Lewy body disease includes 2 entities that could be considered clinical variants of the same pathology: Dementia with Lewy bodies and Parkinson's disease Dementia. Two stages of the disease are described in this review, a prodromal stage and one of explicit dementia. The first one is clinically represented by that period in which, the patient exhibits some typical features of the disease, but not dementia criteria. Despite being difficult to define the prodromal stage and that strong clinical data and biomarkers are still lacking, there is evidence to characterize it mainly by mild selective impairment in attention and visuo-spatial function, REM sleep disorder and dysautonomia. The second stage is clearly characterized in the known consensus criteria of 2005. We have recently published the validation of an instrument called ALBA Screening Instrument which showed a high sensitivity and specificity for diagnosis of the disease even in the early stages. It´s useful to differentiate the disease from other similar pathologies. Positron Emission Tomography for dopamine transporter is the gold standard of diagnosis in life. Symptomatic treatment with anticholinesterases and atypical neuroleptics help patients in their evolution of the disease. Anticholinergics and typical antipsychotics are agents to avoid in the treatmen of the disease because can severely damage patients. Future advances in the diagnosis and dissemination of the knowledge of the disease will contribute to generate greater research efforts to find an effective preventive and / or curative treatment. (AU)

Anti-Allodynic Effects of Levodopa in Neuropathic Rats

PURPOSE: Levodopa is the most effective anti-Parkinsonian agent. It has also been known to exhibit analgesic properties in laboratory and clinical settings. However, studies evaluating its effects on neuropathic pain are limited. The aim of the present study was to examine the anti-allodynic effects of levodopa in neuropathic rats. MATERIALS AND METHODS: Sprague-Dawley male rats underwent the surgical procedure for L5 and L6 spinal nerves ligation. Sixty neuropathic rats were randomly divided into 6 groups for the oral administration of distilled water and levodopa at 10, 30, 50, 70, and 100 mg/kg, respectively. We co-administered carbidopa with levodopa to prevent peripheral synthesis of dopamine from levodopa, and observed tactile, cold, and heat allodynia pre-administration, and at 15, 30, 60, 90, 120, 150, 180, and 240 min after drug administration. We also measured locomotor function of neuropathic rats using rotarod test to examine whether levodopa caused side effects or not. RESULTS: Distilled water group didn't show any difference in all allodynia. For the levodopa groups (10-100 mg/kg), tactile and heat withdrawal thresholds were increased, and cold withdrawal frequency was decreased dose-dependently (p0.05). CONCLUSION: Levodopa reversed tactile, cold and heat allodynia in neuropathic rat without any side effects.

Comparación farmacocinética de Sinemet y Grifoparkin (levodopa/carbidopa 250/25 mg) en pacientes con enfermedad de Parkinson avanzada: un estudio con dosis única / Pharmacokinetic comparison of Sinemet and Grifoparkin (levodopa/carbidopa 250/25 mg) in Parkinson s disease: a single dose study

BACKGROUND: There are doubts wether generic medications have the same bioavailability and efficacy compared with the original drugs developed by pharmaceutical companies with research capabilities. AIM: To compare the pharmacokinetics and clinical (motor) responses of Sinemet and Grifoparkin (generic carbidopa/levodopa 250/25 mg) in patients with advanced Parkinson's disease. PATIENTS AND METHODS: Patients were randomly assigned to Sinemet (15 patients 62 +/- 12 years old; mean disease duration 11 +/- 7 years) or Grifoparkin (15 patients, 64 +/- 11 years old; mean disease duration 12 +/- 4 years) groups. Medication and food were withheld 12 h before the study. Fifteen blood samples were collected (starting 9 AM) immediately before (sample 1, t = 0 min) and after (samples 2-15, t = 20-360 min) oral administration of a single dose of Sinemet or Grifoparkin, and plasmatic L-DOPA was quantified using HPLC with electrochemical detection. Additionally, each patient was clinically evaluated every 20 minutes, using the tapping test and the unified Parkinson's disease scale Hoehn & Yarh. RESULTS: Tmax (time at which the maximal L-DOPA concentration was reached) were 69 +/- 12 min and 64 +/- 11 min for Sinemet and Grifoparkin respectively (NS). Cmax (maximal L-DOPA concentration reached) was 3161 +/- 345 ng/ml for Sinemet and 3274 +/- 520 ng/ml for Grifoparkin (NS). The t1/2 (half life time), CL (clearance) and volume of distribution (Vd) values calculated were 159 +/- 32 min, 51.7 +/- 5.1 1/h and 3.6 +/- 1.2 l/kg for Sinemet and 161 +/- 48 min, 58.7 +/- 8 l/h and 3.0 +/- 0.7 l/kg for Grifoparkin (NS). UPDRS-III value for the best on state and for the worst off state were 23 +/- 11 and 50 +/- 19 for Sinemet and 20 +/- 7 and 46 +/- 13 for Grifoparkin respectively (NS). CONCLUSION: The results obtained showed that both drugs are bioequivalent in patients with advanced Parkinson's disease.

Long term bromocriptine treatment in de novo parkinsonian patients

Aunque la levedopa es la droga de elección en el tratamiento de la enfermedad de Parkinson, los efectos a largo plazo han conducido al ensayo de nuevas combinaciones terapéuticas habiéndose realizado en los últimos años varios estudios que evalúan la asociación con bromocriptina. Sin embargo, no se ha estudiado suficientemente el empleo de bromocriptina como tratamiento inicial y sus efectos a largo plazo. En este trabajo se comparan los resultados del uso prolongado de três esquemas terapéuticos: bromocriptina, levodopa-carbidopa y bromocriptina plus levodupa-carbidopa. Tres grupos de pacientes con enfermedad de Parkinson idiopática vírgenes de tratamiento, fueron evaluados por un período promedio de 31 meses de acuerdo a las escalas de Hoehn & Yahr y de Webster; compromiso clínico e incapacidad pre-tratamiento eran semelhantes entre grupos. Cada grupo fue tratado respectivamente con bromocriptina, levodopa-carbidopa o bromocriptina plus levoduopa-carbidopa (Tabla 1). Todos los pacientes tuvieron mejoría, pero el grupo tratado con bromocriptina sola presentó a lo largo del ensayo, disminución del efecto terapéutico inicial en el 50% de los casos, lo cual obligó al agregado de levodopa, conformando entonces un subgrupo (Fig. 1, Tabla 2). Al final del ensayo no se comprobaron diferencias significativas entre los grupos y subgrupos (Figs. 2, 3, 4), siendo la mejoría observada en los distintos tratamientos de alrededor del 50%. Los efectos colaterales fueron tambíen semejantes, pero menos frecuentes en el grupo tratado con bromocriptina sola (Tabla 3). Esto resultados indican que la bromocriptina sola tiene una efectividad semejante a los otros esquemas terapéuticos y que su efecto es sostenido al menos en el 50% de los casos, con menos efectos colaterales. Se sugiere la conveniencia de comenzar el tratamiento antiparkinsoniano con bromocriptina para definir dosis óptima o ausencia de respuesta y agregar posteriormente levodopa-carbidopa, a fin de minimizar los efectos del tratamiento a largo plazo