Planejamento, síntese e avaliação farmacológica de compostos híbridos potencialmente ativos para o tratamento da anemia falciforme

Sickle cell disease (SCD) is a hereditary hemolytic anemia caused by the inheritance of one S hemoglobin gene from each ancestor. Patients with SCD present increased circulating levels of cytokines, including TNF-alpha (TNF-α). Hydroxyurea (HU) is the available therapeutically strategy for treatment; it acts as a source of nitric oxide and benefits patients by increasing the levels of fetal hemoglobin (HbF). Thus, within one research line that aims at finding new drugs, a series of compounds with TNF-α inhibition and nitric oxide donation properties have been synthesized in order to explore possible synergism of actions beneficial in the treatment of the disease. Six compounds were synthesized: five derivatives of organic nitrates and one of sulfonamide. The compounds, (1,3-dioxo-1,3-dihydro-2Hisoindol-2-yl) methyl nitrate (compound I); (1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl) ethyl nitrate (compound II); 3-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl) benzyl nitrate (compound III);4-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)-N-hydroxybenzenesulfonamide (compound IV); 4-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl) benzyl nitrate (compound V) and 2-[4-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl) phenyl]ethyl nitrate (compound VI), were synthesized using linear synthetic methodology, with excellent overall yields. All compounds showed anti-inflammatory and analgesic effects with a reduction in 43%-65% of ear edema in mice and a reduction of 25%-42% of writhing induced by acetic acid. All compounds showed comparable reductions in the leukocyte infiltration capacity and ability to generate nitric oxide. The aryl compounds (III, IV and V) presented less mutagenic activity compared to compounds I, II and VI according to the salmonella mutagenicity assay (Ames test). Compounds IV and VI showed activity in K562 culture cells, with increases in gamma globin gene expression to levels higher than with hydroxyurea suggesting a potential to increase fetal hemoglobin. This data set characterizes new potentially useful drug candidates for the treatment of symptoms of sickle cell anemia.

Evaluation of HPFH and δβ-thalassemia mutations in a Brazilian group with high Hb F levels.

Fetal hemoglobin (Hb F) is characteristic of the fetal development period. However, in some genetic conditions, such as hereditary persistence of fetal hemoglobin (HPFH) and delta-beta thalassemia (δβ-thalassemia), Hb F continues to be produced in adulthood. We evaluated the frequency of two mutations of HPFH, HPFH-1 and HPFH-2 African, and two mutations in δβ-thalassemia, Sicilian and Spanish, in a Brazilian population. Peripheral blood samples were collected from adults from hospitals and blood centers in southeast and northeast Brazil. These individuals were healthy and without complaints of anemia, but had increased Hb F. Samples were submitted to electrophoretic and chromatographic analyses to quantify Hb F values and, subsequently, to molecular analyses to verify the mutations. In the molecular analysis, 16 of the 60 samples showed a heterozygous profile for the HPFH mutations, two for HPFH-1 and 14 for HPFH-2. In the same sample set, three were heterozygous for Spanish δβ-thalassemia and none were heterozygous for Sicilian δβ- thalassemia. The Hb F values in the HPFH-2 heterozygotes differed from those previously reported for this mutation. In this group, the HPFH mutations were more frequent than the δβ-thalassemia mutations. The finding of these mutations in this Brazilian population reflects the mixing process that occurred during its formation.

Modulação pelo haplótipo Bantu da resposta ao uso de hidroxiureia em anemia falciforme

Pós-graduação em Genética - IBILCE

Efeito da Hidroxiuréia, uma substância de uso médico, sobre parâmetros biológicos de Drosophila melanogaster

Pós-graduação em Genética - IBILCE

Avaliação da expressão da talassemia Beta no Brasil pela coherança com defeitos de hemocromatose

Pós-graduação em Genética - IBILCE

Síntese e avaliação farmacológica de protótipos candidatos à fármacos para o tratamento dos sintomas da anemia falciforme

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Planejamento, síntese e avaliação farmacológica de compostos híbridos potencialmente ativos para o tratamento da anemia falciforme

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Síntese e avaliação farmacológica de novos compostos híbridos úteis para tratamento das complicaçôes da anemia falciforme

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Phenotypic expression of homozygous hemoglobin S in relation to β-globin haplotypes, glutathione S-transferase polymorphisms and detoxification enzymes

Sickle cell anemia (SCA) shows a pathophysiology that involves multiple changes in sickle cell erythrocytes, vaso-occlusive episodes, hemolysis, activation of inflammatory mediators, endothelial cell dysfunction, and oxidative stress. These events complicate treatment and culminate in the development of manifestations such as anemia, pain crises and multiorgan dysfunction. The aim of this study was to evaluate, in SCA patients, oxidative stress and antioxidant capacity markers, correlating them to treatment with hydroxyurea (HU), β-globin haplotypes and glutathione S-transferase polymorphisms (GSTT1, GSTM1 and GSTP1), in comparison to a control group (CG). The study groups were composed of 48 individuals without hemoglobinopathies (CG), SCA patients treated with HU [AF (+HU), N = 13] and untreated SCA patients [AF (-HU), N = 15], after informed consent. The groups were analyzed using cytological, electrophoretic, chromatographic and molecular methods and information from medical records. The GSTM1 and GSTT1 polymorphisms were determined by multiplex PCR, while the GSTP1 polymorphism by PCR-RFLP. Biochemical parameters were measured using spectrophotometric methods [TBARS, TEAC and catalase (CAT) and GST activities] and a chromatographic method [glutathione (GSH)]. The fetal Hb (Hb F) levels observed in the SCA (+HU) group (10.9%) confirmed the already well-described pharmacological effect of HU, but the SCA (-HU) group also had high Hb F levels (6.1%), which may have been influenced by genetic factors not targeted in this study. We found a higher frequency of the Bantu haplotype (48.2%), followed by the Benin (32.1%) and also Cameroon haplotypes, rare in our population, and 19.7% of atypical haplotypes. The presence of Bantu haplotype was related to higher lipid peroxidation levels in patients, but also, it conferred a differential response to HU treatment, raising Hb F levels in 52.6% (P = 0.03). The protective effect of Hb F was confirmed, because the increase in their levels resulted in a 41.3% decrease in lipid peroxidation levels (r = -0.74, P = 0.0156). The genotypic frequency of the GST polymorphisms observed was similar to that of other studies in the Brazilian population, and its association with biochemical markers revealed a significant difference only for the GSTP1 polymorphism, where patients with genotype V/V showed higher GSH and TEAC levels (P = 0.04 and P = 0.03, respectively) compared to patients with genotype I/I. The TBARS levels were about five to eight times higher in the SCA (+HU) and SCA (-HU) groups, respectively, compared to controls, and HU produced a 35.2% decrease in lipid peroxidation levels in the SCA (+HU) group (P < 0.0001). Moreover, the SCA (+HU) group showed higher TEAC levels when compared to CG (P = 0.002). We did not find any significant difference in GST activity between the groups studied (P = 0.76), but CAT activity was about 17 and 30% lower in SCA (+HU) and SCA (-HU) groups, respectively (P < 0.00001). Plasma GSH levels were ~2 times higher in SCA patients than in the control group (P = 0.0005) and showed a positive correlation with TBARS levels, confirming its antioxidant function. HU treatment contributed to higher CAT activity and TEAC levels and lower lipid peroxidation, and its pharmacological effect showed a “haplotype-dependent” response. These findings may contribute to elucidating the potential of HU in ameliorating oxidative stress in SCA subjects.

On the temperature stability of extracellular hemoglobin of Glossoscolex paulistus, at different oxidation states: SAXS and DLS studies

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Detecção ultrassonográfica do ovário fetal em loba-guará (Chrysocyon brachyurus): relato de caso

Identificaram-se, por ultrassonografia, os ovários fetais e o sexo dos fetos em uma loba-guará. Ao exame ultrassonográfico, foi possível identificar estruturas fetais e realizar medidas (relação entre diâmetro cranial e abdominal dos fetos) que indicavam idade fetal de 59 dias. Observaram-se: estruturas torácicas e abdominais formadas, diafragma, membros, estruturas do crânio definidas, coluna vertebral, medula, costelas, batimentos cardíacos normais, movimentação fetal, câmaras e valvas cardíacas, grandes vasos, rins, peristaltismo intestinal e ovários fetais. O exame ultrassonográfico foi eficaz nessa espécie, pois foi possível observar estruturas fetais para a avaliação da viabilidade fetal e, também, identificou-se a imagem ovariana em um dos fetos, mostrando-se importante para estudos de sexagem fetal.

Aspectos da fluência na narrativa oral de indivíduos com Transtorno do Espectro Alcoólico Fetal

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Perfil de habilidades de comunicação de dois irmãos com a Síndrome Alcoólica Fetal

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Anestesia em paciente obstétrica portadora de anemia falciforme e traço talassêmico após plasmaféresis: relato de caso

JUSTIFICATIVA E OBJETIVOS: A plasmaféresis é a técnica de tratamento de escolha para pacientes com anemia hemolítica grave. Uma de suas conseqüências é a depleção de colinesterase plasmática, o que interfere na metabolização de alguns bloqueadores neuromusculares de uso corrente na prática anestesiológica. RELATO do CASO: Paciente com 26 anos, estado físico ASA IV, gestação de 30 semanas e 3 dias, portadora de anemia falciforme, traço talassêmico e alo-imunização para antígenos de alta freqüência. Apresentou crise de falcização, sendo transfundida com derivado sangüíneo incompatível. Evoluiu com hemólise maciça, sendo admitida com hemoglobina de 3 g/dL e hematócrito de 10%, icterícia intensa, taquicardia, apatia e descoramento. Na avaliação hematológica concluiu-se ser situação de inexistência de sangue compatível para transfusão. Foi tratada com corticoterapia, imunoglobulinas e plasmaféresis. No segundo dia de internação, evoluiu com insuficiência renal aguda e edema pulmonar agudo, piora do estado geral e instabilidade hemodinâmica. Indicada a resolução da gestação em decorrência do quadro clínico da paciente e do sofrimento fetal agudo que se sobrepôs. A paciente foi admitida na sala de operações consciente, dispnéica, pálida, ictérica, SpO2 de 91% em ar ambiente, freqüência cardíaca de 110 bpm e pressão arterial de 110 x 70 mmHg, em uso de dopamina (1 µg.kg-1.min-1) e dobutamina (10 µg.kg-1.min-1). Optou-se por anestesia geral balanceada, com alfentanil (2,5 mg), etomidato (14 mg) e atracúrio (35 mg) e isoflurano. Não se observou intercorrências anestésico-cirúrgicas. Ao final, a paciente foi encaminhada à UTI, sob intubação orotraqueal, e em uso de drogas vasoativas, tendo sido extubada após 3 horas. CONCLUSÕES: Este caso mostrou-se um desafio para a equipe, visto que a paciente apresentava instabilidade hemodinâmica e alteração do coagulograma, condições que contra-indicam a anestesia regional; além disto, a plasmaféresis potencialmente depleta os estoques de colinesterases plasmáticas, o que interfere na anestesia. Entretanto, o arsenal medicamentoso disponível permitiu o manuseio seguro desta situação.

Effects of hypertension on maternal adaptations to pregnancy: experimental study on spontaneously hypertensive rats

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)