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1.
Genes (Basel) ; 14(1)2023 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-36672946

RESUMEN

Cellular differentiation relies on the highly conserved Notch signaling pathway. Notch activity induces gene expression changes that are highly sensitive to chromatin landscape. We address Notch gene regulation using Drosophila as a model, focusing on the genetic and molecular interactions between the Notch antagonist Hairless and the histone chaperone Asf1. Earlier work implied that Asf1 promotes the silencing of Notch target genes via Hairless (H). Here, we generate a novel HΔCT allele by genome engineering. Phenotypically, HΔCT behaves as a Hairless gain of function allele in several developmental contexts, indicating that the conserved CT domain of H has an attenuator role under native biological contexts. Using several independent methods to assay protein-protein interactions, we define the sequences of the CT domain that are involved in Hairless-Asf1 binding. Based on previous models, where Asf1 promotes Notch repression via Hairless, a loss of Asf1 binding should reduce Hairless repressive activity. However, tissue-specific Asf1 overexpression phenotypes are increased, not rescued, in the HΔCT background. Counterintuitively, Hairless protein binding mitigates the repressive activity of Asf1 in the context of eye development. These findings highlight the complex connections of Notch repressors and chromatin modulators during Notch target-gene regulation and open the avenue for further investigations.


Asunto(s)
Proteínas de Drosophila , Drosophila melanogaster , Animales , Proteínas Represoras/genética , Proteínas de Drosophila/metabolismo , Chaperonas de Histonas/genética , Chaperonas de Histonas/metabolismo , Alelos , Receptores Notch/genética , Receptores Notch/metabolismo , Drosophila/genética , Cromatina/metabolismo
2.
Worldviews Evid Based Nurs ; 20(1): 79-88, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36453565

RESUMEN

BACKGROUND: Exercise programs in patients with kidney disease improve functional capacity and health-related quality of life, but the implementation of exercise programs in nephrology services is not an easy task. AIM: To evaluate the effectiveness of a home-based exercise program in patients with chronic kidney disease (CKD) stages 4-5 (with or without dialysis). METHODS: A 12-week prospective observational cohort design study was carried out with patients with renal failure who undertook a home-based exercise program. Registered data included: (a) biochemical parameters; (b) functional capacity tests, that is, short physical performance battery, sit to stand to sit 10, and 6-min walking test; (c) handgrip strength; (d) health-related quality of life; (e) satisfaction; and (f) adherence. The quantitative variables were expressed by means and standard deviation, and qualitative variables, by percentage. The comparison of quantitative data between baseline and at 12 weeks of the same group was carried out using the Wilcoxon test for nonparametric-related variables and the chi-square test for categorical variables using contingency tables. RESULTS: Fifty-three patients were included (mean age = 67.4 years). The functional capacity tests showed a significant improvement in the short physical performance battery (8.3 ± 2.8 vs. 9.5 ± 2.6 points), the sit to stand to sit 10 (35.8 ± 17.7 vs. 31.8 ± 15.3 s), and the 6-min walking test (355.0 ± 106.1 vs. 386.4 ± 113.6 meters), mainly in CKD stage 5. There were no significant differences in handgrip and health-related quality of life. Regarding the degree of program satisfaction, 70% of the patients were very satisfied with being able to participate in the program, and 64% considered that they had more strength after completing the home-based exercise program. LINKING EVIDENCE TO ACTION: The implementation of a home-based exercise program results in improved functional capacity in patients with CKD stage 5. Moreover, this exercise program is safe, and patients were satisfied.


Asunto(s)
Calidad de Vida , Insuficiencia Renal Crónica , Humanos , Anciano , Fuerza de la Mano , Rol de la Enfermera , Diálisis Renal , Terapia por Ejercicio/métodos , Insuficiencia Renal Crónica/terapia
3.
EMBO Mol Med ; 14(8): e15230, 2022 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-35781796

RESUMEN

The recent emergence of multiple SARS-CoV-2 variants has caused considerable concern due to both reduced vaccine efficacy and escape from neutralizing antibody therapeutics. It is, therefore, paramount to develop therapeutic strategies that inhibit all known and future SARS-CoV-2 variants. Here, we report that all SARS-CoV-2 variants analyzed, including variants of concern (VOC) Alpha, Beta, Gamma, Delta, and Omicron, exhibit enhanced binding affinity to clinical grade and phase 2 tested recombinant human soluble ACE2 (APN01). Importantly, soluble ACE2 neutralized infection of VeroE6 cells and human lung epithelial cells by all current VOC strains with markedly enhanced potency when compared to reference SARS-CoV-2 isolates. Effective inhibition of infections with SARS-CoV-2 variants was validated and confirmed in two independent laboratories. These data show that SARS-CoV-2 variants that have emerged around the world, including current VOC and several variants of interest, can be inhibited by soluble ACE2, providing proof of principle of a pan-SARS-CoV-2 therapeutic.


Asunto(s)
Enzima Convertidora de Angiotensina 2 , Tratamiento Farmacológico de COVID-19 , Humanos , Peptidil-Dipeptidasa A/genética , Peptidil-Dipeptidasa A/metabolismo , SARS-CoV-2
4.
Worldviews Evid Based Nurs ; 19(4): 322-337, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35635247

RESUMEN

BACKGROUND: Intradialysis exercise programs in renal patients result in improved functional capacity, muscle strength, symptoms of depression, and health-related quality of life. Home-based exercise programs are an alternative to overcome logistical and human resource problems. However, the implementation of these programs is not an easy task and there is a lack of knowledge regarding the benefits associated with home-based exercise programs. AIM: To determine whether home-based exercise programs improve functional capacity, health-related quality of life, muscle strength, and symptoms of depression among patients with stage III-V chronic kidney disease. METHODS: A systematic review and meta-analyses following PRISMA guidelines were utilized. Relevant articles were collected and independently assessed for their inclusion eligibility. Effects of home-based exercise were summarized by the standardized mean differences and represented by forest plots (Review Manager 5.4). RESULTS: Eight studies were included, none of which reported any adverse effects. The intervention was usually aerobic, 76% of these programs lasted 3-6 months, and exercise adherence was 60-87.5%. Four studies measured health-related quality of life and found significant improvements in several subscales. Regarding functional capacity, five studies used the six-minute walking test (44.9 meters; 95% CI [30.45, 59.30]; p ≤ .001), three studies used the sit-to-stand-to-sit test (-0.45 seconds; 95% CI [-0.46, -0.26]; p ≤ .001), and two studies used the timed up-and-go test (-0.76 seconds; 95% CI [-1.38, -0.15]; p ≤ .001) and the handgrip strength test (1.16 kg; 95% CI [-2.88, 5.20]; p ≤ .001). LINKING EVIDENCE TO ACTION: Home-based exercise programs are beneficial to renal patients. These interventions are safe and effective to improve health-related quality of life and functional capacity and reduce symptoms of depression among patients with chronic kidney disease.


Asunto(s)
Calidad de Vida , Insuficiencia Renal Crónica , Ejercicio Físico , Terapia por Ejercicio , Fuerza de la Mano , Humanos , Insuficiencia Renal Crónica/terapia
5.
Sci Rep ; 12(1): 1004, 2022 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-35046421

RESUMEN

Accurate evaluation of physical function in patients undergoing haemodialysis is crucial in the analysis of the impact of exercise programs in this population. The aim of this study was to evaluate the reproducibility of several physical functional tests, depending on the timing of their implementation (before the HD session vs. non-HD days). This is a prospective, non-experimental, descriptive study. Thirty patients in haemodialysis were evaluated twice, 1 week apart. The test session was performed before the haemodialysis session started and a retest was performed in non-dialysis day. The testing battery included the short physical performance battery, sit-to-stand tests, 6 min walk test, one-leg stand test, timed up and go, and handgrip strength with and without forearm support. The intra-rater reproducibility was determined by the intraclass correlation coefficients and the agreement was assessed by Bland-Altman analysis. The intraclass correlation coefficients values ranged from 0.86 to 0.96, so that all tests showed good to very good relative reliability. The mean differences between trials of sit to stand 10 and 60, timed up and go and all the handgrip tests were close to zero, indicating no systematic differences between trials. Large range of values between trials was observed for the 6 min walk test, gait speed, one-leg stand test and short physical performance battery, indicating a systematic bias for these four tests. In conclusion,  the sit to stand 10 and 60, timed up and go and handgrip tests had good to excellent test-retest reliability in measuring physical function in different dialysis days of patients undertaking haemodialysis. The minimal detectable change values are provided for this population. Bias were found for the 6 min walk test, gait speed, Short physical performance battery or one-leg stand test when the testing day changed.


Asunto(s)
Evaluación de la Discapacidad , Rendimiento Físico Funcional , Diálisis Renal , Anciano , Anciano de 80 o más Años , Femenino , Fuerza de la Mano , Humanos , Fallo Renal Crónico , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados , Posición de Pie , Prueba de Paso
6.
bioRxiv ; 2021 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-34545368

RESUMEN

The recent emergence of multiple SARS-CoV-2 variants has caused considerable concern due to reduced vaccine efficacy and escape from neutralizing antibody therapeutics. It is therefore paramount to develop therapeutic strategies that inhibit all known and future SARS-CoV-2 variants. Here we report that all SARS-CoV-2 variants analyzed, including variants of concern (VOC) Alpha, Beta, Gamma, and Delta, exhibit enhanced binding affinity to clinical grade and phase 2 tested recombinant human soluble ACE2 (APN01). Importantly, soluble ACE2 neutralized infection of VeroE6 cells and human lung epithelial cells by multiple VOC strains with markedly enhanced potency when compared to reference SARS-CoV-2 isolates. Effective inhibition of infections with SARS-CoV-2 variants was validated and confirmed in two independent laboratories. These data show that SARS-CoV-2 variants that have emerged around the world, including current VOC and several variants of interest, can be inhibited by soluble ACE2, providing proof of principle of a pan-SARS-CoV-2 therapeutic.

7.
Clin Nurs Res ; 30(3): 360-368, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32075428

RESUMEN

The purpose of this study is to assess whether the functional capacity of patients with chronic kidney disease stage V (CKD-5D) is different depending on their physical activity levels. We also compared functional capacity, quality of life, and symptoms of depression depending on treatment modalities (HD vs. PD). A Cross-sectional study included 52 patients (35HD and 17PD; males 61.5%, mean age 71 years). The main measurements were physical activity level using the Human Activity Profile questionnaire (HAP), muscle strength, functional capacity, health-related quality of life (HRQoL), and depressive symptomatology. The functional tests and physical activity levels correlated significantly. Participants on HD with low physical activity levels were older (*p ≤ .039) and had worst physical function (*p ≤ .01). The HAP is a useful tool to detect subjects with low functional capacity; there were no differences between the therapy modalities in terms of functional capacity, HRQoL, or depressive symptomatology.


Asunto(s)
Calidad de Vida , Insuficiencia Renal Crónica , Estudios Transversales , Ejercicio Físico , Humanos , Masculino , Diálisis Renal
8.
PLoS One ; 13(8): e0201035, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30133445

RESUMEN

Functional tests are commonly used for chronic kidney disease (CKD) patients undergoing hemodialysis (HD). However, the relative and absolute reliability of such physical performance-outcome assessments must first be determined in specific patient cohorts. The aims of this study were to assess the relative and the absolute reliability of the Short Physical Performance Battery (SPPB), One-Legged Stance Test (OLST), and Timed Up and Go (TUG) test, as well as the minimal detectable change (MDC) scores for these tests in CKD patients receiving HD. Seventy-one end-stage CKD patients receiving HD therapy, aged between 21 and 90 years, participated in the study. The patients completed two testing sessions one to two weeks apart and performed by the same examiner, comprising the following tests: the SPPB (n = 65), OLST (n = 62), and TUG test (n = 66). High intraclass correlation coefficients (≥0.90) were found for all the tests, suggesting that their relative reliability is excellent. The MDC scores for the 90% confidence intervals were as follows: 1.7 points for the SPPB, 11.3 seconds for the OLST, and 2.9 seconds for the TUG test. The reliability of the SPPB, OLST, and TUG test for this sample were all considered to be acceptable. The MDC data generated by these tests can be used to monitor meaningful changes in the functional capacity of the daily living-related activity of CKD patients on HD.


Asunto(s)
Terapia por Ejercicio/métodos , Fallo Renal Crónico/fisiopatología , Pruebas de Función Renal/métodos , Adulto , Anciano , Anciano de 80 o más Años , Evaluación de la Discapacidad , Ejercicio Físico , Femenino , Marcha/fisiología , Humanos , Fallo Renal Crónico/clasificación , Fallo Renal Crónico/terapia , Pruebas de Función Renal/estadística & datos numéricos , Masculino , Tamizaje Masivo/métodos , Persona de Mediana Edad , Rendimiento Físico Funcional , Equilibrio Postural/fisiología , Diálisis Renal/métodos , Reproducibilidad de los Resultados , Estudios de Tiempo y Movimiento
9.
J Surg Case Rep ; 2017(4): rjx042, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28458868

RESUMEN

A shortage of donor organs is a major limitation to liver transplantation. Expansion of donor pool criteria to include patients with schistosomiasis diagnosed on liver biopsy might allow the allocation of more transplant livers. Schistosomiasis is a chronic parasitic disease affecting millions in endemic areas including sub-Sahara Africa that might lead to the development of granulomas as a response to the parasite's ova and might cause chronic liver disease and portal hypertension. Due to increased mobility globally, schistosomiasis may be encountered in non-endemic areas. Currently, the usage of donor livers with known Schistosomiasis is not universally defined.

10.
Nefrologia ; 35(4): 385-94, 2015.
Artículo en Inglés, Español | MEDLINE | ID: mdl-26306966

RESUMEN

BACKGROUND: Elderly patients on haemodialysis (HD) are a steadily increasing group. They show a high complexity, dependency and comorbidity. Multiple benefits from exercise in HD patients have been reported; however, they have not been specifically evaluated in an elderly population. OBJECTIVE: To assess the effect of an adapted low intensity intradialytic exercise programme on muscle strength, functional capacity and health-related quality of life in our elderly patients (> 80 years) on HD. MATERIAL AND METHODS: HD patients were non-randomly assigned to an exercise training group (E) or a control group (C) in a 12-week single-centre prospective study. E included a combined exercise programme using balls, weights, elastic bands and cycle movements in the first 2 hours of HD sessions. C group patients received standard HD care. Endpoints were: 1) main biochemical data; 2) maximum quadriceps length strength (MQLS) and hand-grip (HG); 3) functional capacity tests: "Sit to stand to sit" (STS10) and "six-minutes walking test" (6MWT); 4) Beck Depressive Inventory (BDI); and 5) Health-related quality of life questionnaire: EuroQol-5D (EQ-5D). RESULTS: A total of 22 patients were included (50% men). Mean age was 83.2 years; patients had received HD for 44.1 month. Charlson index was 9.5. Main aetiology was diabetes mellitus (36.4%). Eleven patients were assigned to E group and 11 to C group. No related adverse effects were observed. At the end of the study, E group showed an overall improvement in tests (*P<.05): MQLS 10.5 ± 7.6 vs. 12.9 ± 10.1 kg, HG* 16.6 ± 8.7 vs. 18.2 ± 8.9 kg, STS10* 29.9 ± 10.6 vs. 25 ± 7.87 sec, 6MWT* 14.6%, 234.4 vs. 274.7 m, BDI* 14.4 ± 11.5 vs. 11.7 ± 10.8 and EQ-5D 49 ± 19.1 vs. 59.5 ± 20.3. No similar changes were observed in C group. Significant differences between groups were also found for HG, MQLS, STS10, 6MWT, BDI and EQ-5D. No significant changes were found in biochemical and anthropometric data, antidepressant treatment or suitable dialysis parameters at the end of the study. CONCLUSIONS: 1) An adapted low intensity exercise programme improved muscle strength, functional capacity and health-related quality of life in our elderly patients on HD. 2) Our results highlight the benefits from exercise in HD patients even in this elderly population. 3) In elderly patients on HD, it is worth considering an adapted low intensity intradialytic exercise programme as a part of a comprehensive care.


Asunto(s)
Terapia por Ejercicio , Diálisis Renal , Anciano de 80 o más Años , Atención Integral de Salud , Depresión , Femenino , Fuerza de la Mano , Humanos , Masculino , Fuerza Muscular , Gravedad del Paciente , Estudios Prospectivos , Calidad de Vida , Encuestas y Cuestionarios , Resultado del Tratamiento
11.
Int Urol Nephrol ; 47(10): 1709-17, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26253828

RESUMEN

BACKGROUND: Haemodialysis (HD) patients are characterised by muscle wasting, decreased physical function and poor quality of life. The objective was to analyse the effect of an intradialysis NMES training programme in muscular strength, functional capacity and quality of life in our HD patients. MATERIAL: HD patients were assigned to NMES (ESG) or control group (CG) in a 12-week single-centre prospective study. Transversal quadriceps muscular area, maximum length quadriceps strength (MLQS), handgrip, sit-to-stand-to-sit 10 test (STS10), "6-min walking test" (6MWT); EuroQol-5D health-related quality of life (EQ-5D) questionnaire, subjective global assessment (SGA) and NMES symptoms questionnaires (SQ) were completed. RESULTS: Thirty-eight patients (54 % men). Mean age 69.7 years. 32.1 months on HD, 23 ESG and 15 in CG. In contrast with CG, ESG significantly (*p < 0.05) improved MLQS* (10.2 6.7 vs. 13.1 8.1 kg), STS10* (41 18.7 vs. 37.2 23.9 s), 6MWT* (12 %, 280.5 vs. 312.4 m) and EQ-5D score* (52.7 vs. 65.5) at the end of the study. However, lower SQ score* (8.5 vs. 5.8 sympt./patient) in ESG was observed, mainly due to muscular pain* (2.2 vs. 1.2), cramps* (1.6 vs. 1.2), numbness* (1.7 vs. 1.1) or stinging* (1.5 vs. 1.1). In ESG, 44 and 72 % referred better wellness sensation and physical condition in SGA, respectively. CONCLUSIONS: Intradialytic NMES of both quadriceps improved muscular strength, functional capacity and quality of life in our HD patients. With the obtained results, NMES constitutes a novel therapeutic alternative to improve the deteriorated physical condition and quality of life of these patients.


Asunto(s)
Terapia por Estimulación Eléctrica , Fuerza Muscular , Músculo Cuádriceps/patología , Músculo Cuádriceps/fisiopatología , Insuficiencia Renal Crónica/fisiopatología , Anciano , Anciano de 80 o más Años , Atrofia/etiología , Atrofia/fisiopatología , Atrofia/rehabilitación , Prueba de Esfuerzo , Tolerancia al Ejercicio , Femenino , Fuerza de la Mano , Estado de Salud , Humanos , Hipoestesia/etiología , Masculino , Persona de Mediana Edad , Mialgia/etiología , Parestesia/etiología , Estudios Prospectivos , Calidad de Vida , Diálisis Renal , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/terapia , Evaluación de Síntomas , Caminata/fisiología
12.
Psychopharmacology (Berl) ; 206(2): 233-42, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19636538

RESUMEN

RATIONALE: Striatal glutamatergic hyperactivity through the metabotropic receptors and their intracellular signaling pathways is considered critical in the development of levodopa-induced dyskinesias in Parkinson's disease and in experimental parkinsonism. OBJECTIVE: We investigated whether the administration of the metabotropic glutamate antagonist, MPEP, modifies striatal expression of Homer family proteins which are involved in the intracellular mechanisms mediated by these receptors. MATERIALS AND METHODS: Sprague-Dawley rats were unilaterally lesioned in the nigrostriatal pathway with 6-hydroxydopamine (8 microg) and treated with: levodopa (12 mg/kg, i.p.) plus vehicle (n=10) divided in two daily injections; levodopa plus MPEP (1.5 and 3 mg/kg, i.p.; n=6-13) divided in two daily injections; or saline (n=7) for 10 consecutive days. Axial, limb, and orolingual dyskinesias were evaluated. Striatal expression of tyrosine hydroxylase (TH), Homer 1a, 1b/c, and deltaFosB were measured by Western Blot. RESULTS: Animals treated with levodopa showed an increase of dyskinesia score (p<0.01) that was attenuated by the administration of MPEP (p<0.01). In the ipsilateral side of the lesion, striatal TH expression was decreased (p<0.01). No significant differences in striatal Homer 1a or b/c expression were observed between the groups of treatment. Striatal deltaFosB expression increased in the animals treated with levodopa (p<0.05) being attenuated after MPEP administration (p<0.05). MPEP effect was not paralleled by any modification of striatal Homer proteins expression. CONCLUSIONS: These results suggest that Homer protein family is not causally involved in the development of dyskinetic movements induced by levodopa treatment in this animal model of parkinsonism.


Asunto(s)
Proteínas Portadoras/metabolismo , Cuerpo Estriado/efectos de los fármacos , Antagonistas de Aminoácidos Excitadores/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Trastornos Parkinsonianos/patología , Piridinas/farmacología , Animales , Antiparkinsonianos/efectos adversos , Antiparkinsonianos/uso terapéutico , Cuerpo Estriado/metabolismo , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Discinesia Inducida por Medicamentos/etiología , Proteínas de Andamiaje Homer , Levodopa/efectos adversos , Levodopa/uso terapéutico , Masculino , Oxidopamina , Trastornos Parkinsonianos/inducido químicamente , Trastornos Parkinsonianos/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-fos/metabolismo , Ratas , Ratas Sprague-Dawley , Tirosina 3-Monooxigenasa/metabolismo
13.
Biochim Biophys Acta ; 1759(1-2): 32-43, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16542739

RESUMEN

We have previously identified four novel isoforms of PPAR-gamma transcripts in monkey macrophages (J. Zhou, K.M. Wilson, J.D. Medh, Genetic analysis of four novel peroxisome proliferator receptor-gamma splice variants in monkey macrophages. Biochem. Biophys. Res. Commun., 293 (2002) 274-283). The purpose of this study was to ascertain that these isoforms are also present in humans. Specific primers were designed to amplify individual isoform transcripts. The presence of PPAR-gamma4, PPAR-gamma5, and PPAR-gamma7 transcripts in human THP-1 macrophages was confirmed by RT-PCR and sequencing. A transcript corresponding to PPAR-gamma6 was not detected. The presence of novel full-length transcripts and protein was also ascertained by Northern and Western blot analysis. Treatment of THP-1 cells with 15-deoxy-Delta12,14-prostaglandin J2 (15d-PGJ2) resulted in more than 20% induction in the expression of PPAR-gamma5 and PPAR-gamma7 transcripts by both Northern blot analysis and RT-PCR. Another PPAR-gamma ligand, troglitazone, induced expression of only PPAR-gamma5. Both ligands inhibited the expression of PPAR-gamma1 and PPAR-gamma2. Additionally, 15d-PGJ2 and troglitazone increased the level of apolipoprotein E transcript by 60% but decreased lipoprotein lipase expression by 15% in THP-1 cells. The differential regulation of PPAR-gamma transcripts suggests that each transcript isoform may contribute to macrophage function.


Asunto(s)
Empalme Alternativo , Macrófagos/metabolismo , PPAR gamma/análisis , Apolipoproteínas E/genética , Línea Celular , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Lipoproteína Lipasa/genética , PPAR gamma/genética , Isoformas de Proteínas/análisis , Isoformas de Proteínas/genética , Isoformas de Proteínas/fisiología , ARN Mensajero/análisis
14.
Synapse ; 51(2): 140-50, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14618681

RESUMEN

Glutamatergic overactivity might be involved in L-dopa-induced motor complications since glutamate antagonists reverse and prevent L-dopa-induced shortening in motor response duration in 6-hydroxydopamine-lesioned (6-OHDA) rats and improve L-dopa-induced dyskinesias in parkinsonian monkeys and in patients with Parkinson's disease (PD). An increase in the subthalamic nucleus (STN) glutamatergic activity is believed to contribute to the pathophysiology of PD. However, the role of STN activity in L-dopa-induced motor complications is not so clear. In this study, the effect of STN lesions on L-dopa-induced motor response complications was investigated in rats with a nigrostriatal pathway lesion induced by 6-OHDA. Animals were injected with 6-OHDA in the medial forebrain bundle and treated with L-dopa or saline for 22 days. On day 16, animals were randomly distributed in groups that underwent surgery in the STN ipsilateral or contralateral to 6-OHDA lesion, or bilateral. Rotational behavior was measured on days 1, 15, and 22. Attenuation of STN activity by contralateral and bilateral, but not ipsilateral, STN lesion reversed the shortening in motor response duration induced by L-dopa. L-dopa administration, but not saline, induced prominent dyskinesias in 6-OHDA-lesioned rats with additional bilateral STN lesions. The results indicate that bilateral lesions of STN potentiate the duration of L-dopa-induced motor response and facilitate chronic L-dopa-induced abnormal involuntary movements in 6-OHDA-lesioned rats. The characteristics of the abnormal involuntary movements observed in these animals are similar to L-dopa-induced dyskinesias in parkinsonian patients and might be useful as an experimental model for the study of L-dopa-induced dyskinesia.


Asunto(s)
Antiparkinsonianos/toxicidad , Discinesias/etiología , Levodopa/toxicidad , Trastornos Parkinsonianos/fisiopatología , Conducta Estereotipada/efectos de los fármacos , Núcleo Subtalámico/patología , Animales , Conducta Animal , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Lateralidad Funcional , Levodopa/antagonistas & inhibidores , Masculino , Actividad Motora/efectos de los fármacos , Actividad Motora/fisiología , Movimiento/efectos de los fármacos , Movimiento/fisiología , Oxidopamina/toxicidad , Trastornos Parkinsonianos/tratamiento farmacológico , Ratas , Ratas Sprague-Dawley , Rotación , Núcleo Subtalámico/efectos de los fármacos , Factores de Tiempo
15.
J Neurochem ; 86(6): 1328-37, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12950442

RESUMEN

Inactivation of the subthalamic nucleus (STN) or the internal segment of the pallidum (GPi)/entopeduncular nucleus (EP) by deep brain stimulation or lesioning alleviates clinical manifestations of Parkinson's disease (PD) as well as reducing the side-effects of levodopa treatment. However, the effects of STN or entopeduncular nucleus (EP) lesion on levodopa-related motor fluctuations and on neurochemical changes induced by levodopa remain largely unknown. The effects of such lesions on levodopa-induced motor alterations were studied in 6-hydroxydopamine (6-OHDA)-lesioned rats and were assessed neurochemically by analyzing the functional activity of the basal ganglia nuclei, using the expression levels of the mRNAs coding for glutamic acid decarboxylase and cytochrome oxidase as molecular markers of neuronal activity. At the striatal level, preproenkephalin (PPE) mRNA levels were analyzed. We found in 6-OHDA-lesioned rats that a unilateral STN or EP lesion ipsilateral to the 6-OHDA lesion had no effect on either the shortening in the duration of the levodopa-induced rotational response or the levodopa-induced biochemical changes in the basal ganglia nuclei. In contrast, overexpression of PPE mRNA due to levodopa treatment was reversed by the STN or EP lesion. Our study thus shows that lesion of the EP or STN may counteract some of the neurochemical changes induced by levodopa treatment within the striatum.


Asunto(s)
Ganglios Basales/efectos de los fármacos , Núcleo Entopeduncular/fisiopatología , Levodopa/farmacología , Trastornos Parkinsonianos/fisiopatología , Núcleo Subtalámico/fisiopatología , Animales , Ganglios Basales/patología , Ganglios Basales/fisiopatología , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/metabolismo , Cuerpo Estriado/patología , Modelos Animales de Enfermedad , Complejo IV de Transporte de Electrones/genética , Encefalinas/genética , Núcleo Entopeduncular/efectos de los fármacos , Núcleo Entopeduncular/patología , Globo Pálido/efectos de los fármacos , Globo Pálido/metabolismo , Globo Pálido/patología , Glutamato Descarboxilasa/genética , Hibridación in Situ , Isoenzimas/genética , Masculino , Actividad Motora/efectos de los fármacos , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Neuronas/patología , Oxidopamina , Trastornos Parkinsonianos/inducido químicamente , Trastornos Parkinsonianos/tratamiento farmacológico , Trastornos Parkinsonianos/patología , Precursores de Proteínas/genética , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Sustancia Negra/efectos de los fármacos , Sustancia Negra/metabolismo , Sustancia Negra/patología , Núcleo Subtalámico/efectos de los fármacos , Núcleo Subtalámico/patología
16.
Brain Res ; 958(1): 185-91, 2002 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-12468044

RESUMEN

The massive dopaminergic neuronal loss that occurs in Parkinson's disease shows features of apoptosis. In the current study we have characterised the neuronal death in an animal model of Parkinson's disease. 6-Hydroxydopamine infused in the striatum of adult rats induced progressive loss of dopamine neurons, identified as tyrosine hydroxylase immunoreactive profiles, in the ipsilateral substantia nigra starting at day 5 post-lesion (32%). Silver staining revealed the presence of apoptotic profiles with neuronal morphology in the substantia nigra ipsilateral to the intrastriatal 6-hydroxydopamine injection. These apoptotic nuclei were first observed at day 6 post-lesion, peaked between days 7 and 10 and then abruptly declined. The apoptotic morphology of 6-hydroxydopamine-induced neuronal death was confirmed by electron microscopic studies. These data show that intrastriatal 6-hydroxydopamine-induced dopaminergic neuronal death in the adult rat is apoptotic and supports the use of this lesion protocol as an animal model of Parkinson's disease.


Asunto(s)
Apoptosis/fisiología , Neuronas/patología , Oxidopamina , Trastornos Parkinsonianos/fisiopatología , Sustancia Negra/fisiopatología , Simpaticolíticos , Animales , Apoptosis/efectos de los fármacos , Recuento de Células , Núcleo Celular/efectos de los fármacos , Núcleo Celular/patología , Núcleo Celular/ultraestructura , Fragmentación del ADN/efectos de los fármacos , Fragmentación del ADN/fisiología , Modelos Animales de Enfermedad , Dopamina/metabolismo , Inmunohistoquímica , Masculino , Microscopía Electrónica , Neostriado/efectos de los fármacos , Neostriado/patología , Neostriado/fisiopatología , Vías Nerviosas/efectos de los fármacos , Vías Nerviosas/patología , Vías Nerviosas/fisiopatología , Neuronas/efectos de los fármacos , Neuronas/ultraestructura , Trastornos Parkinsonianos/inducido químicamente , Trastornos Parkinsonianos/patología , Ratas , Ratas Sprague-Dawley , Tiempo de Reacción/efectos de los fármacos , Tiempo de Reacción/fisiología , Sustancia Negra/efectos de los fármacos , Sustancia Negra/patología , Tirosina 3-Monooxigenasa/metabolismo
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