Browsing by Author "Ginete, Catarina"
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- An update review of new therapies in sickle cell disease: the prospects for drug combinationsPublication . Lugthart, Sanne; Ginete, Catarina; Kuona, Patience; Brito, Miguel; Inusa, Baba PsalmIntroduction: Sickle cell disease (SCD) is an inherited disorder characterized by polymerization of deoxygenated hemoglobin and microvascular obstruction. Generalized, it affects millions of people over 85% from low-and-middle-income countries. The cardinal feature is generalized pain referred to as vaso-occlusive crises (VOC), multi-organ damage, and premature death.). SCD is the most prevalent inherited reduced life-threatening disorder in the world and over 85% of the world's 400,000 annual births occur in low-and-middle-income countries. In the UK with about 250 annual births (1:200 live births, and over 14,00 living with the disorder. For decades span. Since 1998 Hydroxyurea remained the only disease-modifying therapy until the FDA approved L-glutamine (2017), Crizanlizumab and Voxelotor (2019), and gene therapies (Exa-cel and Lovo-cel, 2023). Areas covered: A literature review, we discuss established and new treatments. We provide an in-depth review of key clinical trials from 2013-2023. However, for pragmatic purposes we have approached this review in line with the different mechanisms of action, considering the possible options for the search performed in Pubmed Central using the search terms [sickle cell disease] or [sickle cell anemia] and the known treatments, i.e. Hydroxycarbamide/Hydroxyurea, L-Glutamine, Voxelotor, Crizanlizumab, Mitapivat, Etopivat, gene therapy, hematopoietic stem cell transplantation, and combination therapy. Clinical trials performed in the last 10 years (November 2013 - November 2023) were selected. Expert opinion: In our opinion section, we recommend the consideration of combination therapies for specific complications such as VOCs, pain, and renal impairment as well as personalized medicine based on disease phenotype and patient patience characteristics. Following the wake of the recent approval of gene therapy for SCD, the more curative option is now a reality, the challenge is addressing how to address issues such as access, affordability, and shared decision-making with families.
- Análise do efeito biológico de extratos de folhas de Carica papaya na viabilidade e na proliferação de células K562Publication . Canteiro, Beatriz; Mendes, Maria; Delgadinho, Mariana; Oliveira, Ketlyn; Ginete, Catarina; Gomes, Mário; Ribeiro, Edna; Brito, Miguel; Gomes, Anita Q.Introdução – A anemia falciforme é uma doença monogénica causada por mutações no gene da β-globina que afeta a estrutura da hemoglobina, sendo associada a diversas complicações clínicas com elevadas taxas de morbilidade e mortalidade. A reativação farmacológica da hemoglobina fetal (HbF) por compostos como a hidroxiureia (HU) é um dos tratamentos atualmente disponíveis; contudo, o seu perfil de segurança e o elevado custo em países subdesenvolvidos limitam a sua utilização. Nesse contexto é essencial estudar novos compostos indutores da HbF com baixa citotoxicidade e que possam estar amplamente disponíveis, como é o caso de extratos de folhas da Carica papaya (CP), uma planta medicinal com propriedades antioxidantes e anti-inflamatórias. Objetivos – Este estudo pretende avaliar o efeito do extrato metanólico das folhas de CP (EMFCP) em parâmetros biológicos como a proliferação e a viabilidade celular em células K562. Método – As células K562 foram expostas durante 72h ao EMFCP a 500 µg/mL e durante 24 horas ao EMFCP (0,5; 50; 100 µg/mL) e à HU (25 μg/mL). A proliferação e viabilidade celular foram analisadas através da quantificação celular pelo método de exclusão do azul de tripano. Resultados – Os resultados demonstram que a proliferação e a viabilidade celular foram afetadas pelo EMFCP apenas na concentração de 500 µg/mL, não se tendo verificado alteração nestes parâmetros nas restantes concentrações utilizadas. Conclusão – Os resultados mostraram que os EMFCP não são citotóxicos quando incubados em células K562 em concentrações inferiores ou iguais a 100 μg/mL, permitindo assim explorar este composto na avaliação do seu potencial terapêutico no contexto da anemia falciforme.
- Are genetic modifiers the answer to different responses to hydroxyurea treatment? A pharmacogenetic study in sickle cell anemia Angolan childrenPublication . Ginete, Catarina; Delgadinho, Mariana; Santos, Brígida; Pinto, Vera; Silva, Carina; Miranda, Armandina; Brito, MiguelSickle cell anemia (SCA) is an inherited disease affecting the hemoglobin that is particularly common in sub-Saharan Africa. Although monogenic, phenotypes are markedly heterogeneous in terms of severity and life span. Hydroxyurea is still the most common treatment for these patients, and the response to treatment is highly variable and seems to be an inherited trait. Therefore, identifying the variants that might predict hydroxyurea response is important for identifying patients who will have a poorer or non-response to treatment, and the ones that are more prone to suffer from severe side effects. In the present pharmacogenetic study, we analyzed the exons of 77 genes described in the literature as potentially associated with hydroxyurea metabolism in Angolan children treated with hydroxyurea and evaluated the drug response considering fetal hemoglobin levels, other hematological and biochemical parameters, hemolysis, number of vaso-occlusive crises and hospitalizations. Thirty variants were identified in 18 of those genes as possibly associated with drug response, five of them in gene DCHS2. Other polymorphisms in this gene were also associated with hematological, biochemical, and clinical parameters. Further research examining the maximum tolerated dose and fixed-dose with a larger sample size is necessary to corroborate these findings.
- Characterization of a cohort of Angolan children with sickle cell anemia treated with hydroxyureaPublication . Santos, Brígida; Ginete, Catarina; Gonçalves, Elisângela; Delgadinho, Mariana; Miranda, Armandina; Faustino, Paula; Arez, Ana Paula; Brito, MiguelBackground: Sickle Cell Anemia (SCA) is a monogenic disease, although its severity and response to treatment are very heterogeneous. Objectives: This study aims to characterize a cohort of Angolan children with SCA and evaluate their response to hydroxyurea (HU) treatment and the potential side effects and toxicity. Methods: The study enrolled 215 patients between 3 and 12 years old before and after the administration of HU, at a fixed dose of 20 mg/kg/day for 12 months. Results: A total of 157 patients started HU medication and 141 of them completed the 12-month treatment. After initiating HU treatment, the frequency of clinical events decreased (transfusions 53.4%, hospitalizations 47.1%). The response to HU medication varied among patients, with some experiencing an increase in fetal hemoglobin (HbF) of <5%. The mean increase in HbF was 11.9%, ranging from 1.8% to 31%. Responders to HU treatment were 57%, inadequate responders 38.7%, and non-adherent 4.2%. No clinical side effects related to HU were reported. Hematological toxicities were transient and reversible. Children naïve to HU and with lower HbF reported a higher number of hospitalizations caused by malaria infection. During HU treatment, the frequency of malaria episodes did not appear to be affected by HbF levels. Conclusions: the present study provided a valuable contribution to the understanding of the clinical and laboratory profiles of Angolan children with SCA. These findings support the evidence that the implementation of prophylactic measures and treatment with HU is associated with increased survival in children with SCA.
- Os cílios primários regulam os níveis de tiorredoxina redutase 1 e de yH2AX em resposta a níveis elevados de glucosePublication . Marques, Rira; Paiva, Mariana; Ginete, Catarina; Nolasco, Sofia; Marinho, Susana H.; Veiga, Luisa; Brito, Miguel; Soares, Helena; Carmona, BrunoA diabetes caracteriza-se por uma anormal capacidade de controlar o nível de glucose na corrente sanguínea, podendo levar a outras complicações, tais como hipertensão, doenças cardiovasculares, e retinopatia. A desregulação dos níveis de glucose na retina tem demonstrado aumentar os níveis de peróxido de hidrogénio, conduzindo a uma rutura na barreira sanguínea da retina, uma das causas de retinopatia diabética. O cílio primário é um organelo que demonstrou ter um papel no controlo do equilíbrio energético e da homeostase da glucose. Defeitos na estrutura e função dos cílios podem resultar no desenvolvimento de várias doenças, conhecidas como ciliopatias, e que incluem fenótipos como obesidade e diabetes. Neste trabalho pretendemos estudar o papel do aumento dos níveis de glucose na montagem de cílios primários em culturas de células do epitélio pigmentar da retina (RPE-1), bem como o papel dos cílios na resposta celular aos níveis elevados de glucose. Para isso, suplementámos os meios de crescimento das células RPE-1 com diferentes concentrações de glucose (5 mM, 25 mM e 5 mM de glucose + 20 mM manitol). Estas células também foram induzidas a montar cílios antes ou depois da suplementação com a glucose. Neste estudo observámos que a suplementação de glucose não afetou o número de células ciliadas, sendo que o comprimento dos cílios foi menor em células suplementadas com 25 mM de glucose. Também avaliámos os níveis nucleares de tiorredoxina redutase 1 (TXNRD1), uma das principais enzimas intervenientes na resposta ao stress oxidativo desencadeado pela hiperglicemia, e de γH2AX, um marcador celular de quebras no DNA e de senescência celular. Observámos que os níveis nucleares de TXNRD1 e de γH2AX são afetados pela adição de glucose e que a existência de cílios modula a resposta das células em resposta a níveis elevados de glucose. Estes resultados mostram que a presença de cílios primários afeta drasticamente a resposta celular às elevadas concentrações de glucose que provavelmente induzem o stress oxidativo, podendo ter um papel crucial no desenvolvimento de retinopatia diabética.
- Comparative efficacy and safety of pharmacological interventions for managing sickle cell disease complications in children and adolescents: a systematic review with network meta-analysesPublication . Tonin, Fernanda; Ginete, Catarina; Ferreira, Joao; Delgadinho, Mariana; Fernandez-Llimos, Fernando; Brito, MiguelObjectives: Sickle cell disease (SCD), an inherited hemoglobinopathy that causes anemia, severe pain, and vaso-occlusive crisis (VOC), is currently recognized as a global public health concern, being the leading cause of pediatric stroke. Our aim was to synthesize the evidence on the efficacy and safety of interventions for managing SCD in this population. Methods: A systematic review with searches in PubMed, Scopus, and Web of Science was performed (April-2022). Randomized controlled trials comparing disease-modifying agents in SCD patients under 18 years old were included. For each outcome of interest, data were pooled by means of Bayesian network meta-analyses with the surface under the cumulative ranking curve analyses (SUCRA). Results were reported as odds ratio (OR) with 95% credibility intervals (CrI). Results: Seventeen trials (1982-2022) mostly from African countries (65%) and North America (53%), assessing the effect of different interventions’ regimens (hydroxyurea [n=6 trials], L-arginine [n=3], antiplatelets [n=2], immunotherapy/monoclonal antibodies [n=2], sulfates [n=2], docosahexaenoic acid [n=1], niprisan [n=1]) and placebo were included. No statistical differences among treatments were found for the main outcomes. SUCRA revealed that immunotherapy/monoclonal antibodies and hydroxyurea 20 mg/kg are potentially more effective against acute chest syndrome (83% and 76% probabilities, respectively), VOC (71% and 80%, respectively) and needing of transfusions (72% and 75%, respectively), while L-arginine (100-200 mg/kg) and placebo were more prone to these events. Although therapies were overall considered safe, antiplatelet and sulfates may lead to more discontinuations and severe adverse events (uncertainty evidence). Results were similar between age subgroups (<10 years vs. 10-19 years). Conclusions: The available evidence on the effect of drugs on managing SCD in children and adolescents is insufficient and weak. No clear definition for some outcomes exists. Hydroxyurea may remain the standard of care for this population, however, long-term well-designed, and well-reported trials comparing new immunotherapy/monoclonal antibodies should be performed.
- Comparative efficacy and safety of pharmacological interventions for sickle cell disease in children and adolescents: a network meta-analysisPublication . Tonin, Fernanda; Ginete, Catarina; Ferreira, J.; Delgadinho, Mariana; Fernandez-Llimos, Fernando; Brito, MiguelBackground: Sickle cell disease (SCD), an inherited hemoglobinopathy characterized by anemia, severe pain, acute chest syndrome (ACS), and vaso-occlusive crisis (VOC), has an important impact on morbidity and mortality worldwide, especially in the pediatric population (over 50% die before age of 5). Although few treatment options are available, new disease-modifying therapies, intended to prevent or reduce SCD-related complications are under development. Previous systematic reviews are limited to adult patients or focused only on gathering data on a few therapies. Aims: Our aim was to synthetize the evidence on the efficacy and safety profiles of pharmacological interventions for managing SCD in children and adolescents. Methods: A systematic review with searches in PubMed, Scopus, and Web of Science was performed (May-2022). The protocol is registered at PROSPERO CRD42022328471. We included randomized controlled trials comparing any disease-modifying agent used to treat SCD complications in patients under 18 years old. The outcomes of interest included: VOC, ACS, transfusions, hospital admission, discontinuation, and serious adverse events. Data were pooled by means of Bayesian network meta-analyses with the surface under the cumulative ranking curve analyses (SUCRA). Results were reported as odds ratio (OR) with 95% credibility intervals (CrI). Additionally, stochastic multicriteria acceptability analyses (SMAA) were performed. The methodological quality of the trials and certainty of evidence were evaluated through RoB 2.0 tool and the GRADE approach, respectively. Results: Overall, 17 randomized controlled trials (n=1,972 patients) published between 1982-2022, conducted mostly in Africa (41%) and North America (35%) were included for analyses. Around one-third of the trials were restricted to homozygous patients for the SCD allele (SS HMZ); yet when reported, patients with heterozygous S-C combination represented less than 30% of the population. Males accounted for 49.0% of the cases, with ages varying from 1 to 19 years old. Almost all trials (n=15, 88.2%) directly compared active drugs with placebo. The evaluated interventions were: hydroxyurea [n=6 trials], L-arginine [n=3], antiplatelets [n=2], immunotherapy/monoclonal antibodies [n=2], sulfates [n=2], docosahexaenoic acid [n=1], niprisan [n=1] (Figure 1). SUCRA and SMAA revealed that immunotherapy/monoclonal antibodies and hydroxyurea 20 mg/kg are potentially more effective against ACS (17% and 24% probabilities, respectively), VOC (around 29% and 20%, respectively) and needing of transfusions (around 25%), while L-arginine (100-200 mg/kg) and placebo were more associated with these events. Although therapies were overall considered safe, antiplatelet and sulfates may lead to more discontinuations and severe adverse events (uncertainty evidence). Results were similar between age subgroups (<10 years vs. 10-19 years). Summary - Conclusion: The available evidence on the effect of drugs on managing SCD in children and adolescents is still insufficient and weak. No clear definition and reporting criteria for some outcomes exist. Hydroxyurea 20 mg/kg/day may remain the standard of care for these patients, however, long-term, well-designed trials comparing new immunotherapy/monoclonal antibodies should be performed. The use of monotherapies with L-arginine, antiplatelets, or sulfates should be avoided given the poor benefit-risk ratio for this population.
- Differential expression of adhesion molecules in sickle cell anemia and gut microbiome effectPublication . Delgadinho, Mariana; Veiga, Luisa; Ginete, Catarina; Santos, Brígida; Miranda, Armandina; Vasconcelos, Jocelyne Neto de; Brito, MiguelSickle cell anemia (SCA) causes a long-standing vascular inflammation state, leading to endothelial dysfunction and chronic overexpression of several adhesion molecules, which contributes to acute and constant vaso-occlusive (VOC) episodes. It has been demonstrated that hydroxyurea (HU) can reduce VOC events, organ damage, blood transfusions, and even the adhesion properties to endothelial cells of SCA subjects. Due to VOC episodes, these patients are also more susceptible to recurrent bacterial translocation and dysbiosis. Given this, our study aimed to uncover the interplay between adhesion molecules, gut microbiome, and hydroxyurea in a population of Angolan SCA children. Serum and fecal samples were obtained before and after HU treatment in 35 children. After HU, four of these adhesion molecules were significantly reduced: sE-selectin (p = 0.002), ADAMTS13 (p = 0.023), sICAM-1 (p = 0.003), and sVCAM-1 (p = 0.018). A positive correlation was observed between the number of neutrophils and sICAM-1, platelets, and sP-selectin, and also between leukocytes, sICAM-1, and sVCAM-1. Most taxa showing a significant correlation mainly belonged to the Clostridiales order. Specifically, from the Clostridium genera, the groups g19, g21, and g34 were all negatively correlated with HbF levels; g19, g21, and g24 positively correlated with leukocytes; g19 positively with neutrophils and sVCAM-1; and g34 positively with E- and P-selectin. Serratia, an opportunistic pathogen, was positively correlated with sE-selectin and sICAM-1 levels. Additionally, a negative correlation was observed between sP-selectin and Bifidobacterium. Research studies in this area could improve our understanding and contribute to finding new prognostic biomarkers to guarantee precise SCA patient stratification and predict severe complications.
- DNA methyltransferase expression (DNMT1, DNMT3a, and DNMT3b) as a potential biomarker in age-related macular degenerationPublication . Camacho, Pedro; Ribeiro, Edna; Pereira, Bruno; Nascimento, João; Rosa, Paulo Caldeira; Henriques, José; Barrão, Sandra; Sadio, Silvia; Quendera, Bruno; Delgadinho, Mariana; Ginete, Catarina; Neves Delgadinho, Mariana Isabel; Honrado Ginete, Ana Catarina; Silva, Carina; Brito, MiguelBackground/Objectives: Age-related macular degeneration (AMD) is a global cause of vision loss, with limited therapeutic options highlighting the need for effective biomarkers. This study aimed to characterize plasma DNA methyltransferase expression (DNMT1, DNMT3A, and DNMT3B) in AMD patients and explore divergent expression patterns across different stages of AMD. Methods: Thirty-eight AMD patients were prospectively enrolled and stratified by disease severity: eAMD, iAMD, nAMD, and aAMD. Comprehensive ophthalmological assessments included best-corrected visual acuity, digital color fundus photographs, and Spectral Domain Optical Coherence Tomography. Peripheral blood samples were collected for RNA extraction and qRT-PCR to access epigenetic effectors’ transcriptional expression, namely DNMT1, DNMT3A, and DNMT3B genes. The collected data were analyzed using IBM SPSS 29. Results: DNMT1 expression was significantly downregulated in late AMD (−0.186 ± 0.341) compared to early/intermediate AMD (0.026 ± 0.246). Within late AMD, aAMD exhibited a marked downregulation of DNMT1 (−0.375 ± 0.047) compared to nAMD (0.129 ± 0.392). DNMT3A and DNMT3B showed similar divergent expression patterns, correlating with disease stage. Conclusions: This study identified stage-specific transcriptional differences in DNMT expression, emphasizing its potential as a biomarker for AMD progression and a target for future research into personalized therapeutic strategies.
- Effects of Carica papaya leaf extracts in transcriptional regulation of fetal hemoglobinPublication . Mendes, M.; Canteiro, Beatriz; Delgadinho, Mariana; Oliveira, Ketlyn; Ginete, Catarina; Gomes, Mário; Ribeiro, Edna; Brito, Miguel; Gomes, Anita Q.Purpose: Sickle cell disease (SCD) is one of the most common human genetic disorders, which is caused by a single point mutation (Glu6Val) on the HBB gene. Currently, one of the treatments for this global health problem involves the induction of fetal hemoglobin (HbF). There are some drugs on the market that pharmacologically induce HbF, namely Hydroxyurea (HU), however, their safety concerns and the expensive cost in low- and middle-income countries limit their use. In this context, it is essential to study novel fetal hemoglobin-inducing compounds that have fewer adverse effects and are widely available, such as natural compounds. Therefore, the main aim of this work was to evaluate the effects of Carica Papaya methanolic leaf extracts (CPMLE) in HbF reactivation.